id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/9603341 | Dittmaier | Ansgar Denner and Stefan Dittmaier | Dyson summation without violating Ward identities and the
Goldstone-boson equivalence theorem | 26 pages, latex, complete ps-file available via anonymous ftp from
ftp://ftp.physik.uni-wuerzburg.de/pub/preprint/1996/WUE-ITP-96-002.ps,
reference added and some comments on Ref.[6] modified | Phys.Rev. D54 (1996) 4499-4514 | 10.1103/PhysRevD.54.4499 | BI-TP 96/02, WUE-ITP-96-002 | hep-ph | null | In contrast to the conventional treatment of gauge theories, in the
background-field method the Ward identities for connected Green functions are
not violated by Dyson summation of self-energies in finite orders of
perturbation theory. Thus, Dyson summation does not spoil gauge cancelations at
high energies which are ruled by the Goldstone-boson equivalence theorem.
Moreover, in the background-field method the precise formulation of the
equivalence theorem in higher orders (including questions of renormalization)
is simplified rendering actual calculations easier. Finally, the equivalence
theorem is also formulated for the Standard Model with a non-linearly realized
scalar sector and for the gauged non-linear $\sigma$-model.
| [
{
"created": "Tue, 19 Mar 1996 11:27:07 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Mar 1996 16:33:20 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Denner",
"Ansgar",
""
],
[
"Dittmaier",
"Stefan",
""
]
] | In contrast to the conventional treatment of gauge theories, in the background-field method the Ward identities for connected Green functions are not violated by Dyson summation of self-energies in finite orders of perturbation theory. Thus, Dyson summation does not spoil gauge cancelations at high energies which are ruled by the Goldstone-boson equivalence theorem. Moreover, in the background-field method the precise formulation of the equivalence theorem in higher orders (including questions of renormalization) is simplified rendering actual calculations easier. Finally, the equivalence theorem is also formulated for the Standard Model with a non-linearly realized scalar sector and for the gauged non-linear $\sigma$-model. |
2109.12657 | Surabhi Tiwari | A. H. Ajjath, Pooja Mukherjee, V. Ravindran, Aparna Sankar and Surabhi
Tiwari | Resummed Higgs boson cross section at next-to SV to $ \rm NNLO + \rm
\overline {NNLL}$ | 51 pages, 6 Figures | null | 10.1140/epjc/s10052-022-10752-9 | IMSc/2021/09/06 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the resummed predictions for inclusive cross section for the
production of Higgs boson at next-to-next-to leading logarithmic ($\rm
\overline {NNLL}$) accuracy taking into account both soft-virtual ($\rm SV$)
and next-to SV ($\rm NSV$) threshold logarithms. We derive the $N$-dependent
coefficients and the $N$-independent constants in Mellin-$N$ space for our
study. Using the minimal prescription we perform the inverse Mellin
transformation and match it with the corresponding fixed order results. We
report in detail the numerical impact of $N$-independent part of resummed
result and explore the ambiguity involved in exponentiating them. By studying
the K factors at different logarithmic accuracy, we find that the perturbative
expansion shows better convergence improving the reliability of the prediction
at $\rm NNLO + \overline{NNLL}$ accuracy. For instance, the cross-section at
$\rm NNLO + \overline{NNLL}$ accuracy reduces by $3.15\%$ as compared to the
$\rm NNLO$ result for the central scale $\mu_R = \mu_F = m_H/2$ at 13 TeV LHC.
We also observe that the resummed $\rm SV + NSV$ result improves the
renormalisation scale uncertainty at every order in perturbation theory. The
uncertainty from the renormalisation scale $\mu_R$ ranges between $(+8.85\%
,-10.12\%)$ at $\rm NNLO$ whereas it goes down to $(+6.54\% , - 8.32\%)$ at
$\rm NNLO + \overline{NNLL}$ accuracy. However, the factorisation scale
uncertainty is worsened by the inclusion of these NSV logarithms hinting the
importance of resummation beyond $\rm NSV$ terms. We also present our
predictions for $\rm SV + NSV$ resummed result at different collider energies.
| [
{
"created": "Sun, 26 Sep 2021 17:33:10 GMT",
"version": "v1"
}
] | 2022-09-21 | [
[
"Ajjath",
"A. H.",
""
],
[
"Mukherjee",
"Pooja",
""
],
[
"Ravindran",
"V.",
""
],
[
"Sankar",
"Aparna",
""
],
[
"Tiwari",
"Surabhi",
""
]
] | We present the resummed predictions for inclusive cross section for the production of Higgs boson at next-to-next-to leading logarithmic ($\rm \overline {NNLL}$) accuracy taking into account both soft-virtual ($\rm SV$) and next-to SV ($\rm NSV$) threshold logarithms. We derive the $N$-dependent coefficients and the $N$-independent constants in Mellin-$N$ space for our study. Using the minimal prescription we perform the inverse Mellin transformation and match it with the corresponding fixed order results. We report in detail the numerical impact of $N$-independent part of resummed result and explore the ambiguity involved in exponentiating them. By studying the K factors at different logarithmic accuracy, we find that the perturbative expansion shows better convergence improving the reliability of the prediction at $\rm NNLO + \overline{NNLL}$ accuracy. For instance, the cross-section at $\rm NNLO + \overline{NNLL}$ accuracy reduces by $3.15\%$ as compared to the $\rm NNLO$ result for the central scale $\mu_R = \mu_F = m_H/2$ at 13 TeV LHC. We also observe that the resummed $\rm SV + NSV$ result improves the renormalisation scale uncertainty at every order in perturbation theory. The uncertainty from the renormalisation scale $\mu_R$ ranges between $(+8.85\% ,-10.12\%)$ at $\rm NNLO$ whereas it goes down to $(+6.54\% , - 8.32\%)$ at $\rm NNLO + \overline{NNLL}$ accuracy. However, the factorisation scale uncertainty is worsened by the inclusion of these NSV logarithms hinting the importance of resummation beyond $\rm NSV$ terms. We also present our predictions for $\rm SV + NSV$ resummed result at different collider energies. |
1503.03478 | Lewis Tunstall | Andreas Crivellin, Martin Hoferichter, Massimiliano Procura, Lewis C.
Tunstall | Light stops, blind spots, and isospin violation in the MSSM | 38 pages, 15 figures. v2: expanded text in Sec. 3 concerning relic
density and (g-2)_mu constraints, clarified text on isospin violation. Fig. 1
is new, minor changes to Figs. 3,4,10. References added, journal version | JHEP 07 (2015) 129 | 10.1007/JHEP07(2015)129 | UWThPh-2015-5, CERN-PH-TH-2015-047 | hep-ph astro-ph.CO nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of the MSSM, we examine several simplified models where only
a few superpartners are light. This allows us to study WIMP--nucleus scattering
in terms of a handful of MSSM parameters and thereby scrutinize their impact on
dark matter direct-detection experiments. Focusing on spin-independent
WIMP--nucleon scattering, we derive simplified, analytic expressions for the
Wilson coefficients associated with Higgs and squark exchange. We utilize these
results to study the complementarity of constraints due to direct-detection,
flavor, and collider experiments. We also identify parameter configurations
that produce (almost) vanishing cross sections. In the proximity of these
so-called blind spots, we find that the amount of isospin violation may be much
larger than typically expected in the MSSM. This feature is a generic property
of parameter regions where cross sections are suppressed, and highlights the
importance of a careful analysis of the nucleon matrix elements and the
associated hadronic uncertainties. This becomes especially relevant once the
increased sensitivity of future direct-detection experiments corners the MSSM
into these regions of parameter space.
| [
{
"created": "Wed, 11 Mar 2015 20:00:05 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Jul 2015 13:01:53 GMT",
"version": "v2"
}
] | 2015-07-28 | [
[
"Crivellin",
"Andreas",
""
],
[
"Hoferichter",
"Martin",
""
],
[
"Procura",
"Massimiliano",
""
],
[
"Tunstall",
"Lewis C.",
""
]
] | In the framework of the MSSM, we examine several simplified models where only a few superpartners are light. This allows us to study WIMP--nucleus scattering in terms of a handful of MSSM parameters and thereby scrutinize their impact on dark matter direct-detection experiments. Focusing on spin-independent WIMP--nucleon scattering, we derive simplified, analytic expressions for the Wilson coefficients associated with Higgs and squark exchange. We utilize these results to study the complementarity of constraints due to direct-detection, flavor, and collider experiments. We also identify parameter configurations that produce (almost) vanishing cross sections. In the proximity of these so-called blind spots, we find that the amount of isospin violation may be much larger than typically expected in the MSSM. This feature is a generic property of parameter regions where cross sections are suppressed, and highlights the importance of a careful analysis of the nucleon matrix elements and the associated hadronic uncertainties. This becomes especially relevant once the increased sensitivity of future direct-detection experiments corners the MSSM into these regions of parameter space. |
0710.3525 | Shaaban Khalil | S. Khalil and A. Masiero | Radiative B-L symmetry breaking in supersymmetric models | 4 pages | Phys.Lett.B665:374-377,2008 | 10.1016/j.physletb.2008.06.063 | null | hep-ph | null | We propose a scheme where the three relevant physics scales related to the
supersymmetry, electroweak, and baryon minus lepton (B-L) breakings are linked
together and occur at the TeV scale. The phenomenological implications in the
Higgs and leptonic sectors are discussed.
| [
{
"created": "Thu, 18 Oct 2007 14:42:40 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Khalil",
"S.",
""
],
[
"Masiero",
"A.",
""
]
] | We propose a scheme where the three relevant physics scales related to the supersymmetry, electroweak, and baryon minus lepton (B-L) breakings are linked together and occur at the TeV scale. The phenomenological implications in the Higgs and leptonic sectors are discussed. |
hep-ph/9312279 | Christo Christov | Chr.V.Christov, K.Goeke, P.Pobilitsa, V.Petrov, M.Wakamatsu and
T.Watabe | $1/N_c$ Rotational Corrections to $g_A$ and Isovector Magnetic Moment of
the Nucleon | (Revtex), 10 pages (3 figures available on request), report
RUB-TPII-53/93 | Phys.Lett.B325:467-472,1994 | 10.1016/0370-2693(94)90041-8 | null | hep-ph | null | The $1/N_c$ rotational corrections to the axial vector constant and the
isovector magnetic moment of the nucleon are studied in the Nambu --
Jona-Lasinio model. We follow a semiclassical quantization procedure in terms
of path integrals in which we can include perturbatively corrections in powers
of angular velocity $\Omega \sim \frac 1{N_c}$. We find non-zero $1/N_c$ order
corrections from both the valence and the Dirac sea quarks. These corrections
are large enough to resolve the long-standing problem of a strong
underestimation of both $g_A$ and $\mu^{IV}$ in the leading order. The axial
constant $g_A$ is well reproduced, whereas the isovector magnetic moment
$\mu^{IV}$ is still underestimated by 25 \%.
| [
{
"created": "Tue, 14 Dec 1993 18:15:00 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Dec 1993 19:47:43 GMT",
"version": "v2"
}
] | 2010-11-01 | [
[
"Christov",
"Chr. V.",
""
],
[
"Goeke",
"K.",
""
],
[
"Pobilitsa",
"P.",
""
],
[
"Petrov",
"V.",
""
],
[
"Wakamatsu",
"M.",
""
],
[
"Watabe",
"T.",
""
]
] | The $1/N_c$ rotational corrections to the axial vector constant and the isovector magnetic moment of the nucleon are studied in the Nambu -- Jona-Lasinio model. We follow a semiclassical quantization procedure in terms of path integrals in which we can include perturbatively corrections in powers of angular velocity $\Omega \sim \frac 1{N_c}$. We find non-zero $1/N_c$ order corrections from both the valence and the Dirac sea quarks. These corrections are large enough to resolve the long-standing problem of a strong underestimation of both $g_A$ and $\mu^{IV}$ in the leading order. The axial constant $g_A$ is well reproduced, whereas the isovector magnetic moment $\mu^{IV}$ is still underestimated by 25 \%. |
2012.11576 | Wen Yin | Fuminobu Takahashi and Wen Yin | Kilobyte Cosmic Birefringence from ALP Domain Walls | 32pages, 5 figures; v3: estimation of anisotropic cosmic
birefringence added, conclusions unchanged, version to appear in JCAP | null | 10.1088/1475-7516/2021/04/007 | TU-1115, IPMU20-0130 | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | ALP domain walls without strings may be formed in the early Universe. We
point out that such ALP domain walls lead to both isotropic and anisotropic
birefringence of cosmic microwave background (CMB) polarization, which reflects
spatial configuration of the domain walls at the recombination. The
polarization plane of the CMB photon coming from each domain is either not
rotated at all or rotated by a fixed angle. For domain walls following the
scaling solution, the cosmic birefringence of CMB is characterized by $2^{N}$,
i.e. $N$-bit, of information with $N = {\cal O}(10^{3-4})$ being equal to the
number of domains at the last scattering surface, and thus the name, $kilobyte~
cosmic~ birefringence$. The magnitude of the isotropic birefringence is
consistent with the recently reported value, while the anisotropic one is
determined by the structure of domains at the last scattering surface. The
predicted cosmic birefringence is universal over a wide range of the ALP mass
and coupling to photons. The detection of both signals will be a smoking-gun
evidence for the ALP domain walls without strings.
| [
{
"created": "Mon, 21 Dec 2020 18:53:54 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Jan 2021 16:29:11 GMT",
"version": "v2"
},
{
"created": "Fri, 26 Feb 2021 12:03:38 GMT",
"version": "v3"
}
] | 2021-04-14 | [
[
"Takahashi",
"Fuminobu",
""
],
[
"Yin",
"Wen",
""
]
] | ALP domain walls without strings may be formed in the early Universe. We point out that such ALP domain walls lead to both isotropic and anisotropic birefringence of cosmic microwave background (CMB) polarization, which reflects spatial configuration of the domain walls at the recombination. The polarization plane of the CMB photon coming from each domain is either not rotated at all or rotated by a fixed angle. For domain walls following the scaling solution, the cosmic birefringence of CMB is characterized by $2^{N}$, i.e. $N$-bit, of information with $N = {\cal O}(10^{3-4})$ being equal to the number of domains at the last scattering surface, and thus the name, $kilobyte~ cosmic~ birefringence$. The magnitude of the isotropic birefringence is consistent with the recently reported value, while the anisotropic one is determined by the structure of domains at the last scattering surface. The predicted cosmic birefringence is universal over a wide range of the ALP mass and coupling to photons. The detection of both signals will be a smoking-gun evidence for the ALP domain walls without strings. |
hep-ph/9507327 | Ezio Maina | E. Accomando, A. Ballestrero and E. Maina (U. of Torino) | Six--jet decay of off--shell WW pairs at $e^+ e^-$ colliders | 8 LaTex pages, 7 figs tarred and compressed | Phys.Lett. B362 (1995) 141-147 | 10.1016/0370-2693(95)01167-O | DFTT 37/95 | hep-ph | null | Six--jet events via WW pairs, $e^+e^- \ar W^+W^- \ar q_1 \overline{q_1} q_2
\overline{q_2} g g$ are studied at tree level using helicity amplitudes. This
is the dominant production mechanism for six--jet final states at Lep II
energy. ISR effects are taken into account. Total production rates as a
function of $y_{cut}$ are given. The relevance of these processes for the issue
of colour reconnection is discussed. The cross section for five--jet production
via WW pairs at Lep II is also presented.
| [
{
"created": "Tue, 18 Jul 1995 10:43:51 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Accomando",
"E.",
"",
"U. of Torino"
],
[
"Ballestrero",
"A.",
"",
"U. of Torino"
],
[
"Maina",
"E.",
"",
"U. of Torino"
]
] | Six--jet events via WW pairs, $e^+e^- \ar W^+W^- \ar q_1 \overline{q_1} q_2 \overline{q_2} g g$ are studied at tree level using helicity amplitudes. This is the dominant production mechanism for six--jet final states at Lep II energy. ISR effects are taken into account. Total production rates as a function of $y_{cut}$ are given. The relevance of these processes for the issue of colour reconnection is discussed. The cross section for five--jet production via WW pairs at Lep II is also presented. |
2304.00250 | Neus Penalva Mart\'inez | Neus Penalva, Jonathan M. Flynn, Eliecer Hern\'andez and Juan Nieves | Study of new physics effects in $\bar B_s\to
D^{(*)}_s\tau^-\bar\nu_\tau$ semileptonic decays using lattice QCD form
factors and heavy quark effective theory | 28 pages, 12 figures, 13 tables | null | null | null | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We benefit from the lattice QCD determination by the HPQCD of the Standard
Model (SM) form factors for the $\bar B_s\to D_s$ [Phys. Rev. D 101, 074513
(2020)] and the SM and tensor ones for the $\bar B_s\to D_s^{*}$
(arXiv:2304.03137 [hep-lat]) semileptonic decays, and the heavy quark effective
theory (HQET) relations for the analogous $B\to D^{(*)}$ decays obtained by
F.U. Bernlochner et al. in Phys. Rev. D 95, 115008 (2017), to extract the
leading and sub-leading Isgur-Wise functions for the $\bar B_s\to D_s^{(*)}$
decays. Further use of the HQET relations allows us to evaluate the
corresponding scalar, pseudoscalar and tensor form factors needed for a
phenomenological study of new physics (NP) effects on the $\bar B_s\to
D_s^{(*)}$ semileptonic decay. At present, the experimental values for the
ratios ${\cal R}_{D^{(*)}}=\Gamma[\bar B\to
D^{(*)}\tau^-\bar\nu_\tau]/\Gamma[\bar B\to D^{(*)}e^-(\mu^-)\bar\nu_{e(\mu)}]$
are the best signal in favor of lepton flavor universality violation (LFUV)
seen in charged current (CC) $b\to c$ decays. In this work we conduct a study
of NP effects on the $\bar B_s\to D_s^{(*)}\tau^-\bar\nu_\tau$ semileptonic
decays by comparing tau spin, angular and spin-angular asymmetry distributions
obtained within the SM and three different NP scenarios. As expected from SU(3)
light-flavor symmetry, we get results close to the ones found in a similar
analysis of the $\bar B\to D^{(*)}$ case. The measurement of the $\bar B_s\to
D_s^{(*)}\ell\bar\nu_\ell$ semileptonic decays, which is within reach of
present experiments, could then be of relevance in helping to establish or rule
out LFUV in CC $b\to c$ transitions.
| [
{
"created": "Sat, 1 Apr 2023 07:56:00 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Oct 2023 10:09:02 GMT",
"version": "v2"
}
] | 2023-10-23 | [
[
"Penalva",
"Neus",
""
],
[
"Flynn",
"Jonathan M.",
""
],
[
"Hernández",
"Eliecer",
""
],
[
"Nieves",
"Juan",
""
]
] | We benefit from the lattice QCD determination by the HPQCD of the Standard Model (SM) form factors for the $\bar B_s\to D_s$ [Phys. Rev. D 101, 074513 (2020)] and the SM and tensor ones for the $\bar B_s\to D_s^{*}$ (arXiv:2304.03137 [hep-lat]) semileptonic decays, and the heavy quark effective theory (HQET) relations for the analogous $B\to D^{(*)}$ decays obtained by F.U. Bernlochner et al. in Phys. Rev. D 95, 115008 (2017), to extract the leading and sub-leading Isgur-Wise functions for the $\bar B_s\to D_s^{(*)}$ decays. Further use of the HQET relations allows us to evaluate the corresponding scalar, pseudoscalar and tensor form factors needed for a phenomenological study of new physics (NP) effects on the $\bar B_s\to D_s^{(*)}$ semileptonic decay. At present, the experimental values for the ratios ${\cal R}_{D^{(*)}}=\Gamma[\bar B\to D^{(*)}\tau^-\bar\nu_\tau]/\Gamma[\bar B\to D^{(*)}e^-(\mu^-)\bar\nu_{e(\mu)}]$ are the best signal in favor of lepton flavor universality violation (LFUV) seen in charged current (CC) $b\to c$ decays. In this work we conduct a study of NP effects on the $\bar B_s\to D_s^{(*)}\tau^-\bar\nu_\tau$ semileptonic decays by comparing tau spin, angular and spin-angular asymmetry distributions obtained within the SM and three different NP scenarios. As expected from SU(3) light-flavor symmetry, we get results close to the ones found in a similar analysis of the $\bar B\to D^{(*)}$ case. The measurement of the $\bar B_s\to D_s^{(*)}\ell\bar\nu_\ell$ semileptonic decays, which is within reach of present experiments, could then be of relevance in helping to establish or rule out LFUV in CC $b\to c$ transitions. |
hep-ph/0204125 | Giulia Ricciardi | Ugo Aglietti, Giulia Ricciardi | Approximate NNLO Threshold Resummation in Heavy Flavour Decays | 16 pages, 3 figures, Latex; minor changes; 2 figures added | Phys.Rev.D66:074003,2002 | 10.1103/PhysRevD.66.074003 | DSF-4/2002 | hep-ph | null | We present an approximate NNLO evaluation of the QCD form factor resumming
large logarithmic perturbative contributions in semi-inclusive heavy flavour
decays.
| [
{
"created": "Thu, 11 Apr 2002 11:05:41 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Aug 2002 20:55:36 GMT",
"version": "v2"
}
] | 2011-01-25 | [
[
"Aglietti",
"Ugo",
""
],
[
"Ricciardi",
"Giulia",
""
]
] | We present an approximate NNLO evaluation of the QCD form factor resumming large logarithmic perturbative contributions in semi-inclusive heavy flavour decays. |
1002.2967 | Benedict von Harling | Tony Gherghetta, Benedict von Harling | A Warped Model of Dark Matter | 26 pages, 2 figures; v2: references added | JHEP 1004:039,2010 | 10.1007/JHEP04(2010)039 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a model of dark matter in a warped extra dimension in which the
dark sector mass scales are naturally generated without supersymmetry. The dark
force, responsible for dark matter annihilating predominantly into leptons, is
mediated by dark photons that naturally obtain a mass in the GeV range via a
dilaton coupling. As well as solving the gauge hierarchy problem, our model
predicts dark matter in the TeV range, including naturally tiny mass splittings
between pseudo-Dirac states. By the AdS/CFT correspondence both the dark photon
and dark matter are interpreted as composite states of the strongly-coupled
dual 4d theory. Thus, in our model the dark sector emerges at the TeV scale
from the dynamics of a new strong force.
| [
{
"created": "Mon, 15 Feb 2010 22:07:42 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Mar 2010 03:05:15 GMT",
"version": "v2"
}
] | 2010-05-27 | [
[
"Gherghetta",
"Tony",
""
],
[
"von Harling",
"Benedict",
""
]
] | We present a model of dark matter in a warped extra dimension in which the dark sector mass scales are naturally generated without supersymmetry. The dark force, responsible for dark matter annihilating predominantly into leptons, is mediated by dark photons that naturally obtain a mass in the GeV range via a dilaton coupling. As well as solving the gauge hierarchy problem, our model predicts dark matter in the TeV range, including naturally tiny mass splittings between pseudo-Dirac states. By the AdS/CFT correspondence both the dark photon and dark matter are interpreted as composite states of the strongly-coupled dual 4d theory. Thus, in our model the dark sector emerges at the TeV scale from the dynamics of a new strong force. |
1601.04165 | Sreerup Raychaudhuri | Debjyoti Bardhan, Gautam Bhattacharyya, Diptimoy Ghosh, Monalisa
Patra, Sreerup Raychaudhuri | A Detailed Analysis of Flavour-changing Decays of Top Quarks as a Probe
of New Physics at the LHC | Version which appears in PRD | Phys. Rev. D94 (2016) no. 1, 015026 | 10.1103/PhysRevD.94.015026 | TIFR-TH/16-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | If the LHC should fail to observe direct signals for new physics, it may
become necessary to look for new physics effects in rare events such as
flavour-changing decays of the top quark, which, in the Standard Model, are
predicted to be too small to be observed. We set up the theoretical framework
in which experimentally accessible results can be expected in models of new
physics, and go on to discuss two models of supersymmetry -- one with conserved
$R$-parity, and one without $R$-parity -- to illustrate how the
flavour-changing signals are predicted in these models. In the latter case,
there is a distinct possibility of detecting the rare decay $t \to c + Z^0$ at
the LHC. We also present a detailed set of very general formulae which can be
used to make similar calculations in diverse models of new physics.
| [
{
"created": "Sat, 16 Jan 2016 14:05:47 GMT",
"version": "v1"
},
{
"created": "Sat, 20 Feb 2016 12:59:27 GMT",
"version": "v2"
},
{
"created": "Mon, 8 Aug 2016 15:54:12 GMT",
"version": "v3"
}
] | 2016-08-09 | [
[
"Bardhan",
"Debjyoti",
""
],
[
"Bhattacharyya",
"Gautam",
""
],
[
"Ghosh",
"Diptimoy",
""
],
[
"Patra",
"Monalisa",
""
],
[
"Raychaudhuri",
"Sreerup",
""
]
] | If the LHC should fail to observe direct signals for new physics, it may become necessary to look for new physics effects in rare events such as flavour-changing decays of the top quark, which, in the Standard Model, are predicted to be too small to be observed. We set up the theoretical framework in which experimentally accessible results can be expected in models of new physics, and go on to discuss two models of supersymmetry -- one with conserved $R$-parity, and one without $R$-parity -- to illustrate how the flavour-changing signals are predicted in these models. In the latter case, there is a distinct possibility of detecting the rare decay $t \to c + Z^0$ at the LHC. We also present a detailed set of very general formulae which can be used to make similar calculations in diverse models of new physics. |
2401.16112 | Xiong-Hui Cao | Xiong-Hui Cao, Meng-Lin Du and Feng-Kun Guo | Photoproduction of the $X(3872)$ beyond vector meson dominance: the
open-charm coupled-channel mechanism | 34 pages, 5 figures, 1 table | null | null | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Hidden-charm exotic hadrons will be searched for and investigated at future
electron-ion colliders. For instance, the $X(3872)$ can be produced through the
exclusive process $\gamma p\to X(3872)p$. The vector meson dominance model has
been commonly employed in estimating the cross sections of such processes.
However, the coupled-channel production mechanism through open-charm
meson-baryon intermediate states may play a crucial role. To assess the
significance of such contributions, we estimate the cross section of the
$\gamma p\to X(3872)p$ reaction assuming the coupled-channel mechanism. For
energies near the threshold, the total cross section is predicted to be of tens
of nanobarns for $\gamma p\to X(3872)p$, which can be measured at future
experimental facilities. Furthermore, the open-charm coupled-channel mechanism
leads to a distinct line shape of the total cross section that can be utilized
to reveal the production dynamics.
| [
{
"created": "Mon, 29 Jan 2024 12:37:24 GMT",
"version": "v1"
}
] | 2024-01-30 | [
[
"Cao",
"Xiong-Hui",
""
],
[
"Du",
"Meng-Lin",
""
],
[
"Guo",
"Feng-Kun",
""
]
] | Hidden-charm exotic hadrons will be searched for and investigated at future electron-ion colliders. For instance, the $X(3872)$ can be produced through the exclusive process $\gamma p\to X(3872)p$. The vector meson dominance model has been commonly employed in estimating the cross sections of such processes. However, the coupled-channel production mechanism through open-charm meson-baryon intermediate states may play a crucial role. To assess the significance of such contributions, we estimate the cross section of the $\gamma p\to X(3872)p$ reaction assuming the coupled-channel mechanism. For energies near the threshold, the total cross section is predicted to be of tens of nanobarns for $\gamma p\to X(3872)p$, which can be measured at future experimental facilities. Furthermore, the open-charm coupled-channel mechanism leads to a distinct line shape of the total cross section that can be utilized to reveal the production dynamics. |
hep-ph/9904279 | Smaragda Lola | John Ellis and Smaragda Lola (CERN) | Can Neutrinos be Degenerate in Mass? | 17 pages, 4 figures. Corrections to typos and notation: rephrased and
clarified statements on impact of induced deviations from bimaximal mixing | Phys.Lett.B458:310-321,1999 | 10.1016/S0370-2693(99)00545-6 | CERN-TH/99-87 | hep-ph astro-ph hep-ex | null | We reconsider the possibility that the masses of the three light neutrinos of
the Standard Model might be almost degenerate and close to the present upper
limits from Tritium beta decay and cosmology. In such a scenario, the
cancellations required by the latest upper limit on neutrinoless double-beta
decay enforce near-maximal mixing that may be compatible only with the
vacuum-oscillation scenario for solar neutrinos. We argue that the mixing
angles yielded by degenerate neutrino mass-matrix textures are not in general
stable under small perturbations. We evaluate within the MSSM the
generation-dependent one-loop renormalization of neutrino mass-matrix textures
that yielded degenerate masses and large mixing at the tree level. We find that
m_{nu_e} > m_{nu_mu} > m_{nu_tau} after renormalization, excluding MSW effects
on solar neutrinos. We verify that bimaximal mixing is not stable, and show
that the renormalized masses and mixing angles are not compatible with all the
experimental constraints, even for tanbeta as low as unity. These results hold
whether the neutrino masses are generated by a see-saw mechanism with heavy
neutrinos weighing approx. 10^{13} GeV or by non-renormalizable interactions at
a scale approx. 10^5 GeV. We also comment on the corresponding renormalization
effects in the minimal Standard Model, in which m_{nu_e} < m_{nu_mu} <
m_{nu_tau}. Although a solar MSW effect is now possible, the perturbed neutrino
masses and mixings are still not compatible with atmospheric- and
solar-neutrino data.
| [
{
"created": "Thu, 8 Apr 1999 21:06:25 GMT",
"version": "v1"
},
{
"created": "Tue, 13 Apr 1999 18:42:21 GMT",
"version": "v2"
}
] | 2009-09-11 | [
[
"Ellis",
"John",
"",
"CERN"
],
[
"Lola",
"Smaragda",
"",
"CERN"
]
] | We reconsider the possibility that the masses of the three light neutrinos of the Standard Model might be almost degenerate and close to the present upper limits from Tritium beta decay and cosmology. In such a scenario, the cancellations required by the latest upper limit on neutrinoless double-beta decay enforce near-maximal mixing that may be compatible only with the vacuum-oscillation scenario for solar neutrinos. We argue that the mixing angles yielded by degenerate neutrino mass-matrix textures are not in general stable under small perturbations. We evaluate within the MSSM the generation-dependent one-loop renormalization of neutrino mass-matrix textures that yielded degenerate masses and large mixing at the tree level. We find that m_{nu_e} > m_{nu_mu} > m_{nu_tau} after renormalization, excluding MSW effects on solar neutrinos. We verify that bimaximal mixing is not stable, and show that the renormalized masses and mixing angles are not compatible with all the experimental constraints, even for tanbeta as low as unity. These results hold whether the neutrino masses are generated by a see-saw mechanism with heavy neutrinos weighing approx. 10^{13} GeV or by non-renormalizable interactions at a scale approx. 10^5 GeV. We also comment on the corresponding renormalization effects in the minimal Standard Model, in which m_{nu_e} < m_{nu_mu} < m_{nu_tau}. Although a solar MSW effect is now possible, the perturbed neutrino masses and mixings are still not compatible with atmospheric- and solar-neutrino data. |
2104.13924 | Kevin Kelly | Carlos A. Arg\"uelles, Kevin J. Kelly, and V\'ictor M. Mu\~noz | Millicharged Particles from the Heavens: Single- and Multiple-Scattering
Signatures | 17 pages + 3 appendices, 11 figures. Comments welcome. Data and code
available at https://github.com/Harvard-Neutrino/HeavenlyMCP | null | 10.1007/JHEP11(2021)099 | FERMILAB-PUB-21-214-T | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | For nearly a century, studying cosmic-ray air showers has driven progress in
our understanding of elementary particle physics. In this work, we revisit the
production of millicharged particles in these atmospheric showers and provide
new constraints for XENON1T and Super-Kamiokande and new sensitivity estimates
of current and future detectors, such as JUNO. We discuss distinct search
strategies, specifically studies of single-energy-deposition events, where one
electron in the detector receives a relatively large energy transfer, as well
as multiple-scattering events consisting of (at least) two relatively small
energy depositions. We demonstrate that these atmospheric search strategies --
especially this new, multiple-scattering signature -- provide significant room
for improvement in the next decade, in a way that is complementary to
anthropogenic, beam-based searches for MeV-GeV millicharged particles. Finally,
we also discuss the implementation of a Monte Carlo simulation for millicharged
particle detection in large-volume neutrino detectors, such as IceCube.
| [
{
"created": "Wed, 28 Apr 2021 18:00:00 GMT",
"version": "v1"
}
] | 2021-12-01 | [
[
"Argüelles",
"Carlos A.",
""
],
[
"Kelly",
"Kevin J.",
""
],
[
"Muñoz",
"Víctor M.",
""
]
] | For nearly a century, studying cosmic-ray air showers has driven progress in our understanding of elementary particle physics. In this work, we revisit the production of millicharged particles in these atmospheric showers and provide new constraints for XENON1T and Super-Kamiokande and new sensitivity estimates of current and future detectors, such as JUNO. We discuss distinct search strategies, specifically studies of single-energy-deposition events, where one electron in the detector receives a relatively large energy transfer, as well as multiple-scattering events consisting of (at least) two relatively small energy depositions. We demonstrate that these atmospheric search strategies -- especially this new, multiple-scattering signature -- provide significant room for improvement in the next decade, in a way that is complementary to anthropogenic, beam-based searches for MeV-GeV millicharged particles. Finally, we also discuss the implementation of a Monte Carlo simulation for millicharged particle detection in large-volume neutrino detectors, such as IceCube. |
hep-ph/0407116 | Christopher D. Carone | Christopher D. Carone and Justin M. Conroy (William and Mary) | Higgsless GUT Breaking and Trinification | 22 pages, LaTeX, 2 eps figures (v3: discussion of mass scales
clarified) | Phys.Rev. D70 (2004) 075013 | 10.1103/PhysRevD.70.075013 | WM-04-107 | hep-ph | null | Boundary conditions on an extra-dimensional interval can be chosen to break
bulk gauge symmetries and to reduce the rank of the gauge group. We consider
this mechanism in models with gauge trinification. We determine the boundary
conditions necessary to break the trinified gauge group directly down to that
of the standard model. Working in an effective theory for the gauge
symmetry-breaking parameters on a boundary, we examine the limit in which the
GUT-breaking sector is Higgsless and show how one may obtain the low-energy
particle content of the minimal supersymmetric standard model. We find that
gauge unification is preserved in this scenario, and that the differential
gauge coupling running is logarithmic above the scale of compactification. We
compare the phenomenology of our model to that of four-dimensional trinified
theories.
| [
{
"created": "Fri, 9 Jul 2004 15:30:04 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Jul 2004 15:19:15 GMT",
"version": "v2"
},
{
"created": "Fri, 24 Sep 2004 16:08:38 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Carone",
"Christopher D.",
"",
"William and Mary"
],
[
"Conroy",
"Justin M.",
"",
"William and Mary"
]
] | Boundary conditions on an extra-dimensional interval can be chosen to break bulk gauge symmetries and to reduce the rank of the gauge group. We consider this mechanism in models with gauge trinification. We determine the boundary conditions necessary to break the trinified gauge group directly down to that of the standard model. Working in an effective theory for the gauge symmetry-breaking parameters on a boundary, we examine the limit in which the GUT-breaking sector is Higgsless and show how one may obtain the low-energy particle content of the minimal supersymmetric standard model. We find that gauge unification is preserved in this scenario, and that the differential gauge coupling running is logarithmic above the scale of compactification. We compare the phenomenology of our model to that of four-dimensional trinified theories. |
2202.07386 | Adeela Afzal | Adeela Afzal, Waqas Ahmed, Mansoor Ur Rehman, and Qaisar Shafi | $\mu$-hybrid Inflation, Gravitino Dark Matter and Stochastic
Gravitational Wave Background from Cosmic Strings | 12 pages, 7 figures | PHYS. REV. D 105, 103539 (2022) | 10.1103/PhysRevD.105.103539 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a successful realization of supersymmetric $\mu$-hybrid inflation
model based on a gauged $U(1)_{B-L}$ extension of the minimal supersymmetric
standard model, with the soft supersymmetry breaking terms are playing an
important role. Successful non-thermal leptogenesis with gravitino dark matter
yields a reheat temperature in the range $2 \times 10^{7} \lesssim T_R \lesssim
5 \times 10^{9}$ GeV. This corresponds to the predictions $2 \times 10^{-18}
\lesssim r\lesssim 4 \times 10^{-13}$ for the tensor to scalar ratio, and $-2
\times 10^{-6} \lesssim dn_s/d\ln k \lesssim -5 \times 10^{-11}$ for the
running of the scalar spectral index. The $B-L$ breaking scale is estimated as
$ 6 \times 10^{14}\lesssim M/ \text{GeV}\lesssim 10^{16}$, calculated at the
central value of the scalar spectral index, $n_s =0.9655$, reported by Planck
2018. Finally, in a grand unified theory setup the dimensionless string tension
parameter associated with the metastable strings is in the range $ 10^{-9}
\lesssim G\mu_\text{cs} \lesssim 10^{-6}$ corresponding to a stochastic
gravitational wave background lying within the 2$\sigma$ bound of the recent
NANOGrav 12.5-yr data.
| [
{
"created": "Tue, 15 Feb 2022 13:23:19 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Jun 2022 09:31:32 GMT",
"version": "v2"
}
] | 2022-06-02 | [
[
"Afzal",
"Adeela",
""
],
[
"Ahmed",
"Waqas",
""
],
[
"Rehman",
"Mansoor Ur",
""
],
[
"Shafi",
"Qaisar",
""
]
] | We present a successful realization of supersymmetric $\mu$-hybrid inflation model based on a gauged $U(1)_{B-L}$ extension of the minimal supersymmetric standard model, with the soft supersymmetry breaking terms are playing an important role. Successful non-thermal leptogenesis with gravitino dark matter yields a reheat temperature in the range $2 \times 10^{7} \lesssim T_R \lesssim 5 \times 10^{9}$ GeV. This corresponds to the predictions $2 \times 10^{-18} \lesssim r\lesssim 4 \times 10^{-13}$ for the tensor to scalar ratio, and $-2 \times 10^{-6} \lesssim dn_s/d\ln k \lesssim -5 \times 10^{-11}$ for the running of the scalar spectral index. The $B-L$ breaking scale is estimated as $ 6 \times 10^{14}\lesssim M/ \text{GeV}\lesssim 10^{16}$, calculated at the central value of the scalar spectral index, $n_s =0.9655$, reported by Planck 2018. Finally, in a grand unified theory setup the dimensionless string tension parameter associated with the metastable strings is in the range $ 10^{-9} \lesssim G\mu_\text{cs} \lesssim 10^{-6}$ corresponding to a stochastic gravitational wave background lying within the 2$\sigma$ bound of the recent NANOGrav 12.5-yr data. |
hep-ph/0411324 | Pol Bernard Gossiaux | Pol Bernard Gossiaux, Vincent Guiho, Joerg Aichelin | Charmonia enhancement in quark-gluon plasma with improved description of
c-quarks phase-distribution | contribution presented at SQM04 | J.Phys. G31 (2005) S1079-S1082 | 10.1088/0954-3899/31/6/062 | null | hep-ph | null | We present a dynamical model of heavy quark evolution in the quark-gluon
plasma (QGP) based on the Fokker-Planck equation. We then apply this model to
the case of central ultra-relativistic nucleus-nucleus collisions performed at
RHIC and estimate the component of $J/\psi$ production (integrated and
differential) stemming from c-$\bar{c}$ pairs that are initially uncorrelated.
| [
{
"created": "Wed, 24 Nov 2004 15:23:35 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Gossiaux",
"Pol Bernard",
""
],
[
"Guiho",
"Vincent",
""
],
[
"Aichelin",
"Joerg",
""
]
] | We present a dynamical model of heavy quark evolution in the quark-gluon plasma (QGP) based on the Fokker-Planck equation. We then apply this model to the case of central ultra-relativistic nucleus-nucleus collisions performed at RHIC and estimate the component of $J/\psi$ production (integrated and differential) stemming from c-$\bar{c}$ pairs that are initially uncorrelated. |
hep-ph/0001164 | null | Stanislaw Mrowczynski and Markus H. Thoma | Hard Loop Approach to Anisotropic Systems | 10 pages, revised to appear in Phys. Rev. D | Phys.Rev.D62:036011,2000 | 10.1103/PhysRevD.62.036011 | null | hep-ph | null | Anisotropic systems of quarks and gluons, which at least for sufficiently
short space-time intervals can be treated as homogeneous and static, are
considered. The gluon polarization tensor of such a system is explicitly
computed within the semiclassical kinetic and Hard Loop diagrammatic theories.
The equivalence of the two approaches is demonstrated. The quark self energy is
computed as well, and finally, the dispersion relations of quarks and gluons in
the anisotropic medium are discussed.
| [
{
"created": "Mon, 17 Jan 2000 14:58:01 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Mar 2000 19:01:25 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Mrowczynski",
"Stanislaw",
""
],
[
"Thoma",
"Markus H.",
""
]
] | Anisotropic systems of quarks and gluons, which at least for sufficiently short space-time intervals can be treated as homogeneous and static, are considered. The gluon polarization tensor of such a system is explicitly computed within the semiclassical kinetic and Hard Loop diagrammatic theories. The equivalence of the two approaches is demonstrated. The quark self energy is computed as well, and finally, the dispersion relations of quarks and gluons in the anisotropic medium are discussed. |
1410.7007 | Sergey Alekhin | S. Alekhin, J. Bluemlein, L. Caminada, K. Lipka, K. Lohwasser, S.
Moch, R. Petti, R. Placakyte | Nucleon PDF separation with the collider and fixed-target data | Few typos fixed | null | null | DESY 14-196, LPN 14-120, SFB/CPP-14-81 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the impact of the recent data obtained by the LHC, Tevatron, and
fixed-target experiments on the nucleon quark distributions with a particular
focus on disentangling different quark species. An improved determination of
the poorly known strange sea distribution is obtained due to including data
from the neutrino-induced deep-inelastic scattering experiments NOMAD and
CHORUS. The impact of the associated (W + c) production data by CMS and ATLAS
on the strange sea determination is also studied and a comparison with earlier
results based on the collider data is discussed. Finally, the recent LHC and
Tevatron data on the charged lepton asymmetry are compared to the NNLO ABM
predictions and the potential of this input in improving the non-strange sea
distributions is evaluated.
| [
{
"created": "Sun, 26 Oct 2014 09:49:24 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Feb 2015 14:53:05 GMT",
"version": "v2"
}
] | 2015-02-16 | [
[
"Alekhin",
"S.",
""
],
[
"Bluemlein",
"J.",
""
],
[
"Caminada",
"L.",
""
],
[
"Lipka",
"K.",
""
],
[
"Lohwasser",
"K.",
""
],
[
"Moch",
"S.",
""
],
[
"Petti",
"R.",
""
],
[
"Placakyte",
"R.",
""
]
] | We consider the impact of the recent data obtained by the LHC, Tevatron, and fixed-target experiments on the nucleon quark distributions with a particular focus on disentangling different quark species. An improved determination of the poorly known strange sea distribution is obtained due to including data from the neutrino-induced deep-inelastic scattering experiments NOMAD and CHORUS. The impact of the associated (W + c) production data by CMS and ATLAS on the strange sea determination is also studied and a comparison with earlier results based on the collider data is discussed. Finally, the recent LHC and Tevatron data on the charged lepton asymmetry are compared to the NNLO ABM predictions and the potential of this input in improving the non-strange sea distributions is evaluated. |
hep-ph/9601357 | null | J.A. Casas, A. Lleyda and C. Mu\~noz | Problems for Supersymmetry Breaking by the Dilaton in Strings from
Charge and Color Breaking | 11 pages LaTex + 3 figures including psfig.tex. (No changes to the
paper, only some references added) | Phys.Lett. B380 (1996) 59-67 | 10.1016/0370-2693(96)00489-3 | FTUAM 96/03, SCIPP-96-03, IEM-FT-124/96 | hep-ph hep-th | null | The general constraints on the parameter space of soft-breaking terms, in
order to avoid dangerous charge and color breaking minima, are applied to the
four-dimensional string scenario where the dilaton is the source of
supersymmetry breaking (dilaton-dominated limit). The results indicate that the
whole parameter space is excluded on these grounds after imposing the present
experimental data on the top mass. The inclusion of a non-vanishing
cosmological constant does not improve essentially the prospects. Possible
way-outs to this situation are briefly discussed.
| [
{
"created": "Mon, 29 Jan 1996 18:58:31 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Jan 1996 17:33:21 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Feb 1996 19:52:35 GMT",
"version": "v3"
}
] | 2009-10-28 | [
[
"Casas",
"J. A.",
""
],
[
"Lleyda",
"A.",
""
],
[
"Muñoz",
"C.",
""
]
] | The general constraints on the parameter space of soft-breaking terms, in order to avoid dangerous charge and color breaking minima, are applied to the four-dimensional string scenario where the dilaton is the source of supersymmetry breaking (dilaton-dominated limit). The results indicate that the whole parameter space is excluded on these grounds after imposing the present experimental data on the top mass. The inclusion of a non-vanishing cosmological constant does not improve essentially the prospects. Possible way-outs to this situation are briefly discussed. |
1905.01105 | Maxim Nefedov | Maxim Nefedov | One-loop corrections to multiscale effective vertices in the EFT for
Multi-Regge processes in QCD | Talk at DIS-2019, misprint in Eq. (3.4) corrected | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The computation of one-loop corrections to the $\gamma^\star Q_+ q$ and
$gR_+g$ effective vertices in the framework of gauge-invariant effective theory
for Multi-Regge processes in QCD is reviewed. Due to consistent implementation
of the "tilted Wilson line" regularization for rapidity divergences, the
gauge-invariance has been preserved at all stages of calculation independently
on the rapidity regulator and cancellation of the power-like dependence on the
regularization variable is traced. Only single-logarithmic rapidity divergence
is left in the final result.
| [
{
"created": "Fri, 3 May 2019 10:31:16 GMT",
"version": "v1"
},
{
"created": "Tue, 28 May 2019 13:44:37 GMT",
"version": "v2"
}
] | 2019-05-29 | [
[
"Nefedov",
"Maxim",
""
]
] | The computation of one-loop corrections to the $\gamma^\star Q_+ q$ and $gR_+g$ effective vertices in the framework of gauge-invariant effective theory for Multi-Regge processes in QCD is reviewed. Due to consistent implementation of the "tilted Wilson line" regularization for rapidity divergences, the gauge-invariance has been preserved at all stages of calculation independently on the rapidity regulator and cancellation of the power-like dependence on the regularization variable is traced. Only single-logarithmic rapidity divergence is left in the final result. |
1605.02794 | Lobsang Dhargyal | Lobsang Dhargyal | $R(D^{(*)})$ and $\mathcal{B}r(B \rightarrow \tau\nu_{\tau})$ in a
Flipped/Lepton-Specific 2HDM with anomalously enhanced charged Higgs coupling
to $\tau$/b | 10 pages | Phys. Rev. D 93, 115009 (2016) | 10.1103/PhysRevD.93.115009 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Babar, Belle and recently LHCb has reported an excess in the measurements of
$R(D^{*})$, $R(D)$ and $\mathcal{B}r(B \rightarrow \tau \nu_{\tau} )$ than
expected from SM, a possible signature of lepton flavor universality violating
NP. In this work we analyze the phenomenological implications for these decay
modes in a Flipped/Lepton-Specific 2HDM with anomalously enhanced Yukawa
coupling of $H^{\pm}$ to $\tau$/b. When experimental and theoretical errors are
added in quadrature, we conclude that this phenomenological extension of SM can
give results in agreement within 1$\sigma$ deviation for the combination of
$R(D^{(*)})$ and $\mathcal{B}r(B \rightarrow \tau \nu_{\tau})$ compare to about
4$\sigma$ deviation from SM from the latest combined[Babar,Belle,LHCb]
experimental data for these observables.
| [
{
"created": "Mon, 9 May 2016 21:53:07 GMT",
"version": "v1"
},
{
"created": "Thu, 12 May 2016 04:25:49 GMT",
"version": "v2"
}
] | 2016-06-15 | [
[
"Dhargyal",
"Lobsang",
""
]
] | Babar, Belle and recently LHCb has reported an excess in the measurements of $R(D^{*})$, $R(D)$ and $\mathcal{B}r(B \rightarrow \tau \nu_{\tau} )$ than expected from SM, a possible signature of lepton flavor universality violating NP. In this work we analyze the phenomenological implications for these decay modes in a Flipped/Lepton-Specific 2HDM with anomalously enhanced Yukawa coupling of $H^{\pm}$ to $\tau$/b. When experimental and theoretical errors are added in quadrature, we conclude that this phenomenological extension of SM can give results in agreement within 1$\sigma$ deviation for the combination of $R(D^{(*)})$ and $\mathcal{B}r(B \rightarrow \tau \nu_{\tau})$ compare to about 4$\sigma$ deviation from SM from the latest combined[Babar,Belle,LHCb] experimental data for these observables. |
hep-ph/0606241 | Hong Mao | Hong Mao, Nicholas Petropoulos, Song Shu, Wei-Qin Zhao | The linear sigma model at a finite isospin chemical potential | 11 pages, 6 figures; Version to appear in J. Phys. G | J.Phys. G32 (2006) 2187-2198 | 10.1088/0954-3899/32/11/012 | null | hep-ph | null | The effect of finite isospin chemical potential to the effective masses of
the mesons at finite temperature is investigated in the framework of the O(4)
linear sigma model with explicit chiral symmetry breaking. We present a
mechanism to include the isospin chemical potential in the model. By using the
Cornwall-Jackiw-Tomboulis method of composite operators, we obtain a set gap
equations for the effective masses of the mesons and get the numerical results
in the Hartree approximation. We find that the introduction of the chemical
potential only affects the mass of the charged pions and sigma, while there is
almost NO effects on the mass of neutral pions.
| [
{
"created": "Thu, 22 Jun 2006 13:13:19 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Sep 2006 07:34:42 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Mao",
"Hong",
""
],
[
"Petropoulos",
"Nicholas",
""
],
[
"Shu",
"Song",
""
],
[
"Zhao",
"Wei-Qin",
""
]
] | The effect of finite isospin chemical potential to the effective masses of the mesons at finite temperature is investigated in the framework of the O(4) linear sigma model with explicit chiral symmetry breaking. We present a mechanism to include the isospin chemical potential in the model. By using the Cornwall-Jackiw-Tomboulis method of composite operators, we obtain a set gap equations for the effective masses of the mesons and get the numerical results in the Hartree approximation. We find that the introduction of the chemical potential only affects the mass of the charged pions and sigma, while there is almost NO effects on the mass of neutral pions. |
1501.07608 | Juan M. Torres-Rincon | Cristina Manuel and Juan M. Torres-Rincon | Dynamical evolution of the chiral magnetic effect: Applications to the
quark-gluon plasma | 41 pages, 14 figures, 3 appendices. Version 2: new global structure
(appendix added), more explanations and additional references. Version
accepted for publication in Physical Review D journal | Phys. Rev. D 92, 074018 (2015) | 10.1103/PhysRevD.92.074018 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the dynamical evolution of the so-called chiral magnetic effect in
an electromagnetic conductor. To this end, we consider the coupled set of
corresponding Maxwell and chiral anomaly equations, and we prove that these can
be derived from chiral kinetic theory. After integrating the chiral anomaly
equation over space in a closed volume, it leads to a quantum conservation law
of the total helicity of the system. A change in the magnetic helicity density
comes together with a modification of the chiral fermion density. We study in
Fourier space the coupled set of anomalous equations and we obtain the
dynamical evolution of the magnetic fields, magnetic helicity density, and
chiral fermion imbalance. Depending on the initial conditions we observe how
the helicity might be transferred from the fermions to the magnetic fields, or
vice versa, and find that the rate of this transfer also depends on the scale
of wavelengths of the gauge fields in consideration. We then focus our
attention on the quark-gluon plasma phase, and analyze the dynamical evolution
of the chiral magnetic effect in a very simple toy model. We conclude that an
existing chiral fermion imbalance in peripheral heavy ion collisions would
affect the magnetic field dynamics, and consequently, the charge dependent
correlations measured in these experiments.
| [
{
"created": "Thu, 29 Jan 2015 21:00:13 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Oct 2015 10:52:40 GMT",
"version": "v2"
}
] | 2015-10-21 | [
[
"Manuel",
"Cristina",
""
],
[
"Torres-Rincon",
"Juan M.",
""
]
] | We study the dynamical evolution of the so-called chiral magnetic effect in an electromagnetic conductor. To this end, we consider the coupled set of corresponding Maxwell and chiral anomaly equations, and we prove that these can be derived from chiral kinetic theory. After integrating the chiral anomaly equation over space in a closed volume, it leads to a quantum conservation law of the total helicity of the system. A change in the magnetic helicity density comes together with a modification of the chiral fermion density. We study in Fourier space the coupled set of anomalous equations and we obtain the dynamical evolution of the magnetic fields, magnetic helicity density, and chiral fermion imbalance. Depending on the initial conditions we observe how the helicity might be transferred from the fermions to the magnetic fields, or vice versa, and find that the rate of this transfer also depends on the scale of wavelengths of the gauge fields in consideration. We then focus our attention on the quark-gluon plasma phase, and analyze the dynamical evolution of the chiral magnetic effect in a very simple toy model. We conclude that an existing chiral fermion imbalance in peripheral heavy ion collisions would affect the magnetic field dynamics, and consequently, the charge dependent correlations measured in these experiments. |
2005.08976 | Andrzej Buras | Andrzej J. Buras and Jean-Marc Gerard | Isospin-breaking in $\varepsilon'/\varepsilon$: Impact of $\eta_0$ at
the Dawn of the 2020s | 18 pages, no figures, typos removed, additional clarifying comments
and one reference added, results unchanged. Version to appear in EPJC | null | 10.1140/epjc/s10052-020-8299-6 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | For direct CP-violation in $K\to\pi\pi$ decays, the usual isospin-breaking
effects at the percent level are amplified by the dynamics behind the $\Delta
I=1/2$ rule and conventionally encoded in $\Omega_{\rm IB}$ parameters. The
updated prediction $\Omega_{\rm IB}^{(8)}=(15.9\pm 8.2)\times 10^{-2}$ of the
Chiral Perturbation Theory for the strong isospin-breaking due to
$\pi_3-\eta_8$ mixing confirms such a tendency but is quite sensitive to the
theoretical input value of the low-energy constant corresponding to the
flavour-singlet $\eta_0$ exchange contribution in this truncated octet scheme.
We rather exploit the phenomenological $\eta_8-\eta_0$ mixing as a probe for
the non-negligible flavour-singlet component of the physical $\eta$ pole to
find $\Omega_{\rm IB}^{(9)}=(35\pm7)\times 10^{-2}$ in a complete nonet scheme.
A large central value in the nonet scheme is thus substituted for a large
uncertainty in the octet one. Including the experimental $\pi^+-\pi^0$ mass
difference as the dominant electromagnetic isospin-breaking, we obtain for the
effective parameter entering the ratio $\epsilon'/\epsilon$ an improved result
$\hat\Omega_{\rm eff}^{(9)}=(29\pm7)\times 10^{-2}$ to be compared with
$\hat\Omega_{\rm eff}^{(8)}=(17\pm9)\times 10^{-2}$ used in recent analyses of
$\epsilon'/\epsilon$. Accordingly, we get a reduction from
$(\epsilon'/\epsilon)_{\rm SM}^{(8)}=(17.4\pm 6.1)\times 10^{-4}$ to
$(\epsilon'/\epsilon)_{\rm SM}^{(9)}=(13.9\pm 5.2)\times 10^{-4}$ and thereby
an effective suppression of $(\epsilon'/\epsilon)_{\rm SM}$ by isospin-breaking
corrections as large as $40\%$ relative to the recent RBC-UKQCD value.
| [
{
"created": "Mon, 18 May 2020 18:00:02 GMT",
"version": "v1"
},
{
"created": "Tue, 26 May 2020 11:01:20 GMT",
"version": "v2"
},
{
"created": "Mon, 10 Aug 2020 05:29:23 GMT",
"version": "v3"
}
] | 2020-08-26 | [
[
"Buras",
"Andrzej J.",
""
],
[
"Gerard",
"Jean-Marc",
""
]
] | For direct CP-violation in $K\to\pi\pi$ decays, the usual isospin-breaking effects at the percent level are amplified by the dynamics behind the $\Delta I=1/2$ rule and conventionally encoded in $\Omega_{\rm IB}$ parameters. The updated prediction $\Omega_{\rm IB}^{(8)}=(15.9\pm 8.2)\times 10^{-2}$ of the Chiral Perturbation Theory for the strong isospin-breaking due to $\pi_3-\eta_8$ mixing confirms such a tendency but is quite sensitive to the theoretical input value of the low-energy constant corresponding to the flavour-singlet $\eta_0$ exchange contribution in this truncated octet scheme. We rather exploit the phenomenological $\eta_8-\eta_0$ mixing as a probe for the non-negligible flavour-singlet component of the physical $\eta$ pole to find $\Omega_{\rm IB}^{(9)}=(35\pm7)\times 10^{-2}$ in a complete nonet scheme. A large central value in the nonet scheme is thus substituted for a large uncertainty in the octet one. Including the experimental $\pi^+-\pi^0$ mass difference as the dominant electromagnetic isospin-breaking, we obtain for the effective parameter entering the ratio $\epsilon'/\epsilon$ an improved result $\hat\Omega_{\rm eff}^{(9)}=(29\pm7)\times 10^{-2}$ to be compared with $\hat\Omega_{\rm eff}^{(8)}=(17\pm9)\times 10^{-2}$ used in recent analyses of $\epsilon'/\epsilon$. Accordingly, we get a reduction from $(\epsilon'/\epsilon)_{\rm SM}^{(8)}=(17.4\pm 6.1)\times 10^{-4}$ to $(\epsilon'/\epsilon)_{\rm SM}^{(9)}=(13.9\pm 5.2)\times 10^{-4}$ and thereby an effective suppression of $(\epsilon'/\epsilon)_{\rm SM}$ by isospin-breaking corrections as large as $40\%$ relative to the recent RBC-UKQCD value. |
2309.07448 | Usman Hasan | Ishtiaq Ahmed, Usman Hasan, Shahin Iqbal, M. Junaid, Bilal Tariq, A.
Uzair | Analysis of final state lepton polarization-dependent observables in
$H\to \ell^{+}\ell^{-} \gamma$ in the SM at loop level | Version 3.0 28 pages, 7 figures | null | 10.1007/JHEP05(2024)187 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, the CMS and ATLAS collaborations have announced the results for
$H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ with $\ell=e$ or $\mu$
\cite{CMS:2022ahq,CMS:2023mku}, where $H\rightarrow Z\gamma$ is a sub-process
of $H\rightarrow \ell^{+} \ell^{-} \gamma$. This semi-leptonic Higgs decay
receives loop induced resonant $H\rightarrow Z[\rightarrow
\ell^{+}\ell^{-}]\gamma$ as well as non-resonant contributions. % as discussed
in \cite{Kachanovich:2021pvx}.
To probe further features coming from these contributions to $H\rightarrow
\ell^{+} \ell^{-} \gamma$, we argue that the polarization of the final state
leptons is also an important parameter. We show that the contribution from the
interference of resonant and non-resonant terms plays an important role when
the polarization of final state lepton is taken into account, which is
negligible in the case of unpolarized leptons. For this purpose, we have
calculated the polarized decay rates and the longitudinal ($P_L$), normal
($P_N$) and transverse ($P_T$) polarization asymmetries. We find that these
asymmetries purely come from the loop contributions and are helpful to further
investigate the resonant and non-resonant nature of $H\rightarrow Z[\rightarrow
\ell^{+}\ell^{-}]\gamma$ decay. We observe that for $\ell=e,\mu$, the
longitudinal decay rate is highly suppressed around $m_{\ell\ell}\approx 60$GeV
when the final lepton spin is $-\frac{1}{2}$, dramatically increasing the
corresponding lepton polarization asymmetries. Furthermore, we analyze another
observable, the ratio of decay rates $R^{\ell\ell'}_{i\pm}$, where $\ell$ and
$\ell'$ refer to different final state lepton generations. Precise measurements
of these observables at the HL-LHC and the planned $e^{+}e^{-}$ can provide a
fertile ground to test not only the SM but also to examine the signatures of
possible NP beyond the SM.
| [
{
"created": "Thu, 14 Sep 2023 06:10:26 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Sep 2023 03:52:24 GMT",
"version": "v2"
},
{
"created": "Wed, 24 Jan 2024 07:41:02 GMT",
"version": "v3"
}
] | 2024-05-22 | [
[
"Ahmed",
"Ishtiaq",
""
],
[
"Hasan",
"Usman",
""
],
[
"Iqbal",
"Shahin",
""
],
[
"Junaid",
"M.",
""
],
[
"Tariq",
"Bilal",
""
],
[
"Uzair",
"A.",
""
]
] | Recently, the CMS and ATLAS collaborations have announced the results for $H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ with $\ell=e$ or $\mu$ \cite{CMS:2022ahq,CMS:2023mku}, where $H\rightarrow Z\gamma$ is a sub-process of $H\rightarrow \ell^{+} \ell^{-} \gamma$. This semi-leptonic Higgs decay receives loop induced resonant $H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ as well as non-resonant contributions. % as discussed in \cite{Kachanovich:2021pvx}. To probe further features coming from these contributions to $H\rightarrow \ell^{+} \ell^{-} \gamma$, we argue that the polarization of the final state leptons is also an important parameter. We show that the contribution from the interference of resonant and non-resonant terms plays an important role when the polarization of final state lepton is taken into account, which is negligible in the case of unpolarized leptons. For this purpose, we have calculated the polarized decay rates and the longitudinal ($P_L$), normal ($P_N$) and transverse ($P_T$) polarization asymmetries. We find that these asymmetries purely come from the loop contributions and are helpful to further investigate the resonant and non-resonant nature of $H\rightarrow Z[\rightarrow \ell^{+}\ell^{-}]\gamma$ decay. We observe that for $\ell=e,\mu$, the longitudinal decay rate is highly suppressed around $m_{\ell\ell}\approx 60$GeV when the final lepton spin is $-\frac{1}{2}$, dramatically increasing the corresponding lepton polarization asymmetries. Furthermore, we analyze another observable, the ratio of decay rates $R^{\ell\ell'}_{i\pm}$, where $\ell$ and $\ell'$ refer to different final state lepton generations. Precise measurements of these observables at the HL-LHC and the planned $e^{+}e^{-}$ can provide a fertile ground to test not only the SM but also to examine the signatures of possible NP beyond the SM. |
2310.14014 | Gregory Patellis | M. A. May Pech, M. Mondrag\'on, G. Patellis and G.Zoupanos | Reduction of Couplings in the Type-II 2HDM | 13 pages, 2 tables | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The idea of reduction of couplings consists in the search for relations
between seemingly independent couplings of a renormalizable theory that are
renormalization group invariant. In this article, we demonstrate the existence
of such 1-loop relations among the top Yukawa, the Higgs quartic and the gauge
colour couplings of the Type-II Two Higgs Doublet Model at a high-energy
boundary. The phenomenological viability of the reduced theory suggests the
value of $\tan\beta$ and the scale in which new physics may appear.
| [
{
"created": "Sat, 21 Oct 2023 13:54:05 GMT",
"version": "v1"
}
] | 2023-10-24 | [
[
"Pech",
"M. A. May",
""
],
[
"Mondragón",
"M.",
""
],
[
"Patellis",
"G.",
""
],
[
"Zoupanos",
"G.",
""
]
] | The idea of reduction of couplings consists in the search for relations between seemingly independent couplings of a renormalizable theory that are renormalization group invariant. In this article, we demonstrate the existence of such 1-loop relations among the top Yukawa, the Higgs quartic and the gauge colour couplings of the Type-II Two Higgs Doublet Model at a high-energy boundary. The phenomenological viability of the reduced theory suggests the value of $\tan\beta$ and the scale in which new physics may appear. |
2405.11906 | Leonarc Michelle Santos | Leonarc Michelle Santos, Vince Angelo A. Chavez, Denny Lane B.
Sombillo | Pole structure of $P_\psi^N(4312)^+$ via machine learning and
uniformized S-matrix | 11 pages, 4 figures, 7 tables | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We probed the pole structure of the $P_\psi^{N}(4312)^{+}$ using a trained
deep neural network. The training dataset was generated using uniformized
independent S-matrix poles to ensure that the obtained interpretation is as
model-independent as possible. To prevent possible ambiguity in the
interpretation of the pole structure, we included the contribution from the
off-diagonal element of the S-matrix. Five out of the six neural networks we
trained favor $P_\psi^{N}(4312)^{+}$ as possibly having a three-pole structure,
with one pole on each of the unphysical sheets - a first in its report. The two
poles can be associated to a pole-shadow pair which is a characteristic of a
true resonance. On the other hand, the last pole is most likely associated with
the coupled-channel effect. The combined effect of these poles produced a peak
below the $\Sigma^{+}_C\bar{D}^0$ which mimic the line shape of a hadronic
molecule.
| [
{
"created": "Mon, 20 May 2024 09:40:06 GMT",
"version": "v1"
},
{
"created": "Sat, 25 May 2024 02:38:49 GMT",
"version": "v2"
}
] | 2024-05-28 | [
[
"Santos",
"Leonarc Michelle",
""
],
[
"Chavez",
"Vince Angelo A.",
""
],
[
"Sombillo",
"Denny Lane B.",
""
]
] | We probed the pole structure of the $P_\psi^{N}(4312)^{+}$ using a trained deep neural network. The training dataset was generated using uniformized independent S-matrix poles to ensure that the obtained interpretation is as model-independent as possible. To prevent possible ambiguity in the interpretation of the pole structure, we included the contribution from the off-diagonal element of the S-matrix. Five out of the six neural networks we trained favor $P_\psi^{N}(4312)^{+}$ as possibly having a three-pole structure, with one pole on each of the unphysical sheets - a first in its report. The two poles can be associated to a pole-shadow pair which is a characteristic of a true resonance. On the other hand, the last pole is most likely associated with the coupled-channel effect. The combined effect of these poles produced a peak below the $\Sigma^{+}_C\bar{D}^0$ which mimic the line shape of a hadronic molecule. |
1508.07686 | Chien-Wen Hwang | Chi-Yee Cheung and Chien-Wen Hwang | Three symmetry breakings in strong and radiative decays of strange heavy
mesons | 26 pages, 9 figures; several changes made for further clarity; one
figure and some references added; results and conclusions unchanged, version
to appear in Eur. Phys. J. C. arXiv admin note: substantial text overlap with
arXiv:1401.3917 | Eur.Phys.J. C76 (2016) 1, 19 | 10.1140/epjc/s10052-016-3883-5 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we investigate three symmetry breaking effects in strong and
radiative decays of strange heavy mesons. We study 1/m_Q corrections within the
heavy quark effect theory, as well as SU(3) and SU(2) symmetry breakings
induced by light quark mass differences and the \eta-\pi mixing vertex. These
effects are studied in a covariant model. The numerical results show that the
1/m_Q corrections of the coupling constants are consistent with \alpha_s
\Lambda_{QCD}/m_Q. The SU(3) symmetry violating effect of the strong coupling
constant is obviously larger than that of the magnetic coupling constant. The
value of the \eta-\pi mixing vertex has some changes because of the renewed
data. As compared with the other theoretical calculations and the experimental
data, our radiative decay rates are much larger than those of the other
theoretical methods, except for \chiPT; however, our branching ratios are close
to the experimental data.
| [
{
"created": "Mon, 31 Aug 2015 04:46:43 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Jan 2016 07:20:16 GMT",
"version": "v2"
}
] | 2016-02-17 | [
[
"Cheung",
"Chi-Yee",
""
],
[
"Hwang",
"Chien-Wen",
""
]
] | In this paper, we investigate three symmetry breaking effects in strong and radiative decays of strange heavy mesons. We study 1/m_Q corrections within the heavy quark effect theory, as well as SU(3) and SU(2) symmetry breakings induced by light quark mass differences and the \eta-\pi mixing vertex. These effects are studied in a covariant model. The numerical results show that the 1/m_Q corrections of the coupling constants are consistent with \alpha_s \Lambda_{QCD}/m_Q. The SU(3) symmetry violating effect of the strong coupling constant is obviously larger than that of the magnetic coupling constant. The value of the \eta-\pi mixing vertex has some changes because of the renewed data. As compared with the other theoretical calculations and the experimental data, our radiative decay rates are much larger than those of the other theoretical methods, except for \chiPT; however, our branching ratios are close to the experimental data. |
1012.4714 | Bugaev | Edgar Bugaev | Physics of high energy atmospheric muons | Based on the invited talk on the XVI International Symposium on Very
High Energy Cosmic Ray Interactions (ISVHECRI 2010), Batavia, IL, USA (28
June - 2 July 2010), 7 pages, 8 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the first part of the talk the interesting new results of MINOS, OPERA and
CMS collaborations (connected with the observational evidence of the rise in
the muon charge ratio at muon energies around 1 TeV) are briefly discussed from
theoretical point of view. A short review of charge asymmetric effects in muon
energy losses is given. In the second part of the talk, the modern theoretical
approaches to the problem of heavy quark production in high energy
nucleon-nucleus interactions are briefly considered (color dipole formalism,
saturation models). The recent new theoretical developments in the ancient
problem of intrinsic charm are also discussed.
| [
{
"created": "Tue, 21 Dec 2010 16:10:37 GMT",
"version": "v1"
}
] | 2010-12-22 | [
[
"Bugaev",
"Edgar",
""
]
] | In the first part of the talk the interesting new results of MINOS, OPERA and CMS collaborations (connected with the observational evidence of the rise in the muon charge ratio at muon energies around 1 TeV) are briefly discussed from theoretical point of view. A short review of charge asymmetric effects in muon energy losses is given. In the second part of the talk, the modern theoretical approaches to the problem of heavy quark production in high energy nucleon-nucleus interactions are briefly considered (color dipole formalism, saturation models). The recent new theoretical developments in the ancient problem of intrinsic charm are also discussed. |
hep-ph/0601051 | Graham Shore | G.M. Shore | Pseudoscalar Meson Decay Constants and Couplings, the Witten-Veneziano
Formula beyond large N_c, and the Topological Susceptibility | 27 pages, 4 figures | Nucl.Phys. B744 (2006) 34-58 | 10.1016/j.nuclphysb.2006.03.011 | SWAT 04-418 | hep-ph hep-th | null | The QCD formulae for the radiative decays $\eta,\eta'\to\c\c$, and the
corresponding Dashen--Gell-Mann--Oakes--Renner relations, differ from
conventional PCAC results due to the gluonic $U(1)_A$ axial anomaly. This
introduces a critical dependence on the gluon topological susceptibility. In
this paper, we revisit our earlier theoretical analysis of radiative
pseudoscalar decays and the DGMOR relations and extract explicit experimental
values for the decay constants. This is our main result. The flavour singlet
DGMOR relation is the generalisation of the Witten-Veneziano formula beyond
large $N_c$, so we are able to give a quantitative assessment of the
realisation of the $1/N_c$ expansion in the $U(1)_A$ sector of QCD.
Applications to other aspects of $\eta'$ physics, including the relation with
the first moment sum rule for the polarised photon structure function $g_1^\c$,
are highlighted. The $U(1)_A$ Goldberger-Treiman relation is extended to
accommodate SU(3) flavour breaking and the implications of a more precise
measurement of the $\eta$ and $\eta'$-nucleon couplings are discussed. A
comparison with the existing literature on pseudoscalar meson decay constants
using large-$N_c$ chiral Lagrangians is also made.
| [
{
"created": "Fri, 6 Jan 2006 18:49:07 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Shore",
"G. M.",
""
]
] | The QCD formulae for the radiative decays $\eta,\eta'\to\c\c$, and the corresponding Dashen--Gell-Mann--Oakes--Renner relations, differ from conventional PCAC results due to the gluonic $U(1)_A$ axial anomaly. This introduces a critical dependence on the gluon topological susceptibility. In this paper, we revisit our earlier theoretical analysis of radiative pseudoscalar decays and the DGMOR relations and extract explicit experimental values for the decay constants. This is our main result. The flavour singlet DGMOR relation is the generalisation of the Witten-Veneziano formula beyond large $N_c$, so we are able to give a quantitative assessment of the realisation of the $1/N_c$ expansion in the $U(1)_A$ sector of QCD. Applications to other aspects of $\eta'$ physics, including the relation with the first moment sum rule for the polarised photon structure function $g_1^\c$, are highlighted. The $U(1)_A$ Goldberger-Treiman relation is extended to accommodate SU(3) flavour breaking and the implications of a more precise measurement of the $\eta$ and $\eta'$-nucleon couplings are discussed. A comparison with the existing literature on pseudoscalar meson decay constants using large-$N_c$ chiral Lagrangians is also made. |
hep-ph/9610224 | null | Howard Baer and Michal Brhlik | QCD Improved $b\to s\gamma$ Constraints on the Minimal Supergravity
Model | 14 pages REVTEX plus 7 PS figures; this version contains revised
figures and text due to discovery of a bug in the program used to generate
results for the previous version of this manuscript | Phys.Rev.D55:3201-3208,1997 | 10.1103/PhysRevD.55.3201 | FSU-HEP-961001 | hep-ph | null | Recent advances in the QCD corrections to $b\to s\gamma$ decay in the MSSM
include i.) evaluation of the relevant operators, Wilson coefficients and
anomalous dimension matrix elements for the various MSSM effective theories
valid at scales beyond $Q =M_W$, ii.) calculations of most of the needed
anomalous dimension matrix elements to next-to-leading order for scales
$m_b\alt Q <M_W$, and iii.) calculations of ${\cal O}(\alpha_s)$ virtual and
bremsstrahlung corrections to the $b\to s\gamma$ decay operators at scale
$Q\sim m_b$. We assemble all these known results to gain an estimate of $B(b\to
s\gamma )$ for the parameter space of the minimal supergravity model (mSUGRA).
We find a much reduced scale dependence of our result compared to usual
leading-log evaluations. Comparison with the latest CLEO results yields
stringent constraints on parameter space. Much of mSUGRA parameter space is
ruled out for $\mu <0$, especially for large $tan\beta$. We compare these
results with other constraints from cosmology and non-standard vacua. Also, we
compare with expectations for discovering mSUGRA at LEP2, the Tevatron and the
CERN LHC.
| [
{
"created": "Wed, 2 Oct 1996 21:05:50 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Oct 1996 15:18:15 GMT",
"version": "v2"
}
] | 2011-01-27 | [
[
"Baer",
"Howard",
""
],
[
"Brhlik",
"Michal",
""
]
] | Recent advances in the QCD corrections to $b\to s\gamma$ decay in the MSSM include i.) evaluation of the relevant operators, Wilson coefficients and anomalous dimension matrix elements for the various MSSM effective theories valid at scales beyond $Q =M_W$, ii.) calculations of most of the needed anomalous dimension matrix elements to next-to-leading order for scales $m_b\alt Q <M_W$, and iii.) calculations of ${\cal O}(\alpha_s)$ virtual and bremsstrahlung corrections to the $b\to s\gamma$ decay operators at scale $Q\sim m_b$. We assemble all these known results to gain an estimate of $B(b\to s\gamma )$ for the parameter space of the minimal supergravity model (mSUGRA). We find a much reduced scale dependence of our result compared to usual leading-log evaluations. Comparison with the latest CLEO results yields stringent constraints on parameter space. Much of mSUGRA parameter space is ruled out for $\mu <0$, especially for large $tan\beta$. We compare these results with other constraints from cosmology and non-standard vacua. Also, we compare with expectations for discovering mSUGRA at LEP2, the Tevatron and the CERN LHC. |
1010.6058 | Alexander Belyaev | Elena Accomando, Alexander Belyaev, Luca Fedeli, Stephen F.King,
Claire Shepherd-Themistocleous | Z' physics with early LHC data | 25 pages, 14 figures, revtex, references added | Phys.Rev.D83:075012,2011 | 10.1103/PhysRevD.83.075012 | SHEP-10-36 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the prospects for setting limits on or discovering spin-1 $Z'$
bosons using early LHC data at 7 TeV. Our results are based on the narrow width
approximation in which the leptonic Drell-Yan $Z'$ boson production
cross-section only depends on the $Z'$ boson mass together with two parameters
$c_u$ and $c_d$. We carefully discuss the experimental cuts that should be
applied and tabulate the theoretical next-to-next-to-leading order corrections
which must be included. Using these results the approach then provides a safe,
convenient and unbiased way of comparing experiment to theoretical models which
avoids any built-in model dependent assumptions. We apply the method to three
classes of perturbative $Z'$ boson benchmark models: $E_6$ models, left-right
symmetric models and sequential standard models. We generalise each class of
model in terms of {mixing angles which continuously parametrize} linear
combinations of pairs of generators and lead to distinctive orbits in the
$c_u-c_d$ plane. We also apply this method to the strongly coupled four-site
benchmark model in which two $Z'$ bosons are predicted. By comparing the
experimental limits or discovery bands to the theoretical predictions on the
$c_u$-$c_d$ plane, we show that the LHC at 7 TeV with integrated luminosity of
500 pb$^{-1}$ will greatly improve on current Tevatron mass limits for the
benchmark models. If a $Z'$ is discovered our results show that measurement of
the mass and cross-section will provide a powerful discriminator between the
benchmark models using this approach.
| [
{
"created": "Thu, 28 Oct 2010 19:18:09 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Nov 2010 19:21:40 GMT",
"version": "v2"
}
] | 2011-04-22 | [
[
"Accomando",
"Elena",
""
],
[
"Belyaev",
"Alexander",
""
],
[
"Fedeli",
"Luca",
""
],
[
"King",
"Stephen F.",
""
],
[
"Shepherd-Themistocleous",
"Claire",
""
]
] | We discuss the prospects for setting limits on or discovering spin-1 $Z'$ bosons using early LHC data at 7 TeV. Our results are based on the narrow width approximation in which the leptonic Drell-Yan $Z'$ boson production cross-section only depends on the $Z'$ boson mass together with two parameters $c_u$ and $c_d$. We carefully discuss the experimental cuts that should be applied and tabulate the theoretical next-to-next-to-leading order corrections which must be included. Using these results the approach then provides a safe, convenient and unbiased way of comparing experiment to theoretical models which avoids any built-in model dependent assumptions. We apply the method to three classes of perturbative $Z'$ boson benchmark models: $E_6$ models, left-right symmetric models and sequential standard models. We generalise each class of model in terms of {mixing angles which continuously parametrize} linear combinations of pairs of generators and lead to distinctive orbits in the $c_u-c_d$ plane. We also apply this method to the strongly coupled four-site benchmark model in which two $Z'$ bosons are predicted. By comparing the experimental limits or discovery bands to the theoretical predictions on the $c_u$-$c_d$ plane, we show that the LHC at 7 TeV with integrated luminosity of 500 pb$^{-1}$ will greatly improve on current Tevatron mass limits for the benchmark models. If a $Z'$ is discovered our results show that measurement of the mass and cross-section will provide a powerful discriminator between the benchmark models using this approach. |
1712.08298 | Khaled Abdel-Waged Khaled Abdel-Waged | Khaled Abdel-Waged, Nuha Felemban | Nucleon shadowing effects in $Cu+Cu$ and $Au+Au$ collisions at RHIC
within the HIJING code | 18 pages, 10 figures | Abdel-Waged et al 2017 J. Phys. G: Nucl. Part. Phys | 10.1088/1361-6471/aaa101 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The centrality dependence of pseudorapidity density of charged particles ($
dN_{ch}/d\eta $) in $Cu+Cu$ ($Au+Au$) collisions at RHIC energy of $
\sqrt{s_{_{\rm NN}}}=22.4$ , $62.4 $ and $200$ ($19.6$, $62.4$ and $200$) GeV,
is investigated within an improved HIJING code. The standard HIJING model is
enhanced by a prescription for collective nucleon-nucleon ($NN$) interactions
and more modern parton distribution functions. The collective $NN$-interactions
are used to induce both cascade and nucleon shadowing effects. We find
collective cascade broadens the pseudorapidity distributions in the tails (at $
|\eta|> y_{\rm beam} $) above $25-30\%$ collision centrality to be consistent
with the $ dN_{ch}/d\eta $ data at $ \sqrt{s_{_{\rm NN}}}=19.6$, $22.4$, $62.4
$ GeV. The overall contribution of nucleon shadowing is shown to depress the
whole shape of $ dN_{ch}/d\eta$ in the primary interaction region (at $ |\eta|<
y_{\rm beam} $) for semiperipheral ($ 20-25 $ \%) and peripheral ($\ge
35-40$\%) $Cu+Cu$ ($Au+Au$) interactions at $ \sqrt{s_{_{\rm NN}}}=200$ GeV, in
accordance with the PHOBOS data.
| [
{
"created": "Fri, 22 Dec 2017 04:07:55 GMT",
"version": "v1"
}
] | 2017-12-25 | [
[
"Abdel-Waged",
"Khaled",
""
],
[
"Felemban",
"Nuha",
""
]
] | The centrality dependence of pseudorapidity density of charged particles ($ dN_{ch}/d\eta $) in $Cu+Cu$ ($Au+Au$) collisions at RHIC energy of $ \sqrt{s_{_{\rm NN}}}=22.4$ , $62.4 $ and $200$ ($19.6$, $62.4$ and $200$) GeV, is investigated within an improved HIJING code. The standard HIJING model is enhanced by a prescription for collective nucleon-nucleon ($NN$) interactions and more modern parton distribution functions. The collective $NN$-interactions are used to induce both cascade and nucleon shadowing effects. We find collective cascade broadens the pseudorapidity distributions in the tails (at $ |\eta|> y_{\rm beam} $) above $25-30\%$ collision centrality to be consistent with the $ dN_{ch}/d\eta $ data at $ \sqrt{s_{_{\rm NN}}}=19.6$, $22.4$, $62.4 $ GeV. The overall contribution of nucleon shadowing is shown to depress the whole shape of $ dN_{ch}/d\eta$ in the primary interaction region (at $ |\eta|< y_{\rm beam} $) for semiperipheral ($ 20-25 $ \%) and peripheral ($\ge 35-40$\%) $Cu+Cu$ ($Au+Au$) interactions at $ \sqrt{s_{_{\rm NN}}}=200$ GeV, in accordance with the PHOBOS data. |
1910.10008 | Akira Watanabe | Akira Watanabe, Takahiro Sawada, Mei Huang | Extraction of gluon distributions from structure functions at small x in
holographic QCD | 6 pages, 4 figures; v2: version accepted for publication in Phys.
Lett. B | null | 10.1016/j.physletb.2020.135470 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the nucleon and pion gluon distribution functions in the
framework of holographic QCD, focusing on the small Bjorken x region. Based on
an approximate relation, the gluon distributions are extracted from structure
functions of the unpolarized deep inelastic scattering which can be calculated
with a holographic QCD model, assuming the Pomeron exchange. All the adjustable
parameters of the model are determined with the HERA data of the proton
structure functions. We explicitly show that the extracted proton gluon
distribution is consistent with results of the recent global QCD analysis. The
structure functions of the pion can be computed without any additional
parameter, which enables us to predict its gluon distribution also. We find
that the resulting pion gluon density is smaller than the proton's, and agrees
with the recent global QCD analysis result within the uncertainties.
| [
{
"created": "Tue, 22 Oct 2019 14:34:49 GMT",
"version": "v1"
},
{
"created": "Tue, 5 May 2020 07:28:06 GMT",
"version": "v2"
}
] | 2020-06-24 | [
[
"Watanabe",
"Akira",
""
],
[
"Sawada",
"Takahiro",
""
],
[
"Huang",
"Mei",
""
]
] | We investigate the nucleon and pion gluon distribution functions in the framework of holographic QCD, focusing on the small Bjorken x region. Based on an approximate relation, the gluon distributions are extracted from structure functions of the unpolarized deep inelastic scattering which can be calculated with a holographic QCD model, assuming the Pomeron exchange. All the adjustable parameters of the model are determined with the HERA data of the proton structure functions. We explicitly show that the extracted proton gluon distribution is consistent with results of the recent global QCD analysis. The structure functions of the pion can be computed without any additional parameter, which enables us to predict its gluon distribution also. We find that the resulting pion gluon density is smaller than the proton's, and agrees with the recent global QCD analysis result within the uncertainties. |
1604.04526 | Geraldine Servant | Iason Baldes, Thomas Konstandin and Geraldine Servant | A First-Order Electroweak Phase Transition from Varying Yukawas | 6 pages, 4 figures; v2: PLB version (includes references to explicit
realisations studied in the mean time) | null | 10.1016/j.physletb.2018.10.015 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We show that the dynamics responsible for the variation of the Yukawa
couplings of the Standard Model fermions generically leads to a very strong
first-order electroweak phase transition, assuming that the Yukawa couplings
are large and of order 1 before the electroweak phase transition and reach
their present value afterwards. There are good motivations to consider that the
flavour structure could emerge during electroweak symmetry breaking, for
example if the Froggatt-Nielsen field dynamics were linked to the Higgs field.
In this paper, we do not need to assume any particular theory of flavour and
show in a model-independent way how the nature of the electroweak phase
transition is completely changed when the Standard Model Yukawas vary at the
same time as the Higgs is acquiring its vacuum expectation value. The thermal
contribution of the fermions creates a barrier between the symmetric and broken
phase minima of the effective potential, leading to a first-order phase
transition. This offers new routes for generating the baryon asymmetry at the
electroweak scale, strongly tied to flavour models.
| [
{
"created": "Fri, 15 Apr 2016 14:50:50 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Dec 2018 21:51:34 GMT",
"version": "v2"
}
] | 2018-12-10 | [
[
"Baldes",
"Iason",
""
],
[
"Konstandin",
"Thomas",
""
],
[
"Servant",
"Geraldine",
""
]
] | We show that the dynamics responsible for the variation of the Yukawa couplings of the Standard Model fermions generically leads to a very strong first-order electroweak phase transition, assuming that the Yukawa couplings are large and of order 1 before the electroweak phase transition and reach their present value afterwards. There are good motivations to consider that the flavour structure could emerge during electroweak symmetry breaking, for example if the Froggatt-Nielsen field dynamics were linked to the Higgs field. In this paper, we do not need to assume any particular theory of flavour and show in a model-independent way how the nature of the electroweak phase transition is completely changed when the Standard Model Yukawas vary at the same time as the Higgs is acquiring its vacuum expectation value. The thermal contribution of the fermions creates a barrier between the symmetric and broken phase minima of the effective potential, leading to a first-order phase transition. This offers new routes for generating the baryon asymmetry at the electroweak scale, strongly tied to flavour models. |
1112.4771 | Laslo Reichert | Carolina Arbel\'aez, Martin Hirsch, Laslo Reichert | Supersymmetric mass spectra and the seesaw type-I scale | 17 pages, 7 figures | null | 10.1007/JHEP02(2012)112 | IFIC/11-70 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate supersymmetric mass spectra with cMSSM boundary conditions and a
type-I seesaw mechanism added to explain current neutrino data. Using
published, estimated errors on SUSY mass observables for a combined LHC+ILC
analysis, we perform a theoretical $\chi^2$ analysis to identify parameter
regions where pure cMSSM and cMSSM plus seesaw type-I might be distinguishable
with LHC+ILC data. The most important observables are determined to be the
(left) smuon and selectron masses and the splitting between them, respectively.
Splitting in the (left) smuon and selectrons is tiny in most of cMSSM parameter
space, but can be quite sizeable for large values of the seesaw scale,
$m_{SS}$. Thus, for very roughly $m_{SS} \ge 10^{14}$ GeV hints for type-I
seesaw might appear in SUSY mass measurements. Since our numerical results
depend sensitively on forecasted error bars, we discuss in some detail the
accuracies, which need to be achieved, before a realistic analysis searching
for signs of type-I seesaw in SUSY spectra can be carried out.
| [
{
"created": "Tue, 20 Dec 2011 17:01:07 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Arbeláez",
"Carolina",
""
],
[
"Hirsch",
"Martin",
""
],
[
"Reichert",
"Laslo",
""
]
] | We calculate supersymmetric mass spectra with cMSSM boundary conditions and a type-I seesaw mechanism added to explain current neutrino data. Using published, estimated errors on SUSY mass observables for a combined LHC+ILC analysis, we perform a theoretical $\chi^2$ analysis to identify parameter regions where pure cMSSM and cMSSM plus seesaw type-I might be distinguishable with LHC+ILC data. The most important observables are determined to be the (left) smuon and selectron masses and the splitting between them, respectively. Splitting in the (left) smuon and selectrons is tiny in most of cMSSM parameter space, but can be quite sizeable for large values of the seesaw scale, $m_{SS}$. Thus, for very roughly $m_{SS} \ge 10^{14}$ GeV hints for type-I seesaw might appear in SUSY mass measurements. Since our numerical results depend sensitively on forecasted error bars, we discuss in some detail the accuracies, which need to be achieved, before a realistic analysis searching for signs of type-I seesaw in SUSY spectra can be carried out. |
1904.10967 | Djuna Croon | Djuna Croon, Rachel Houtz, and Veronica Sanz | Dynamical Axions and Gravitational Waves | 22 pages, 4 figures. Version published in JHEP | JHEP 1907 (2019) 146 | 10.1007/JHEP07(2019)146 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we explore the possibility of observable gravitational waves as
a manifestation of the QCD axion dynamics. In particular, we focus on dynamical
axion models which solve the strong CP problem, and include the confinement of
a QCD-like gauge group at the TeV scale. We study the resulting chiral symmetry
breaking phase transition for models with $N_F=3$ and $N_F=4$ light flavors
using the linear sigma model. This model describes the scalar meson spectrum
and its interactions, with the diagonal field $\varphi$ as the order parameter.
We find that the amplitude of the gravitational wave spectrum depends on the
mass of the dynamical axion $\eta'$ via the ratio $m_{\eta'}/m_\varphi$. The
resulting spectra may be observed at future mid-range gravitational wave
experiments such as AION/MAGIS, DECIGO, and BBO. Moreover, the TeV states can
be searched for at colliders and their quantum numbers characterized, providing
a unique connection between axion physics, gravitational waves and collider
searches.
| [
{
"created": "Wed, 24 Apr 2019 18:00:00 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Jul 2019 20:54:24 GMT",
"version": "v2"
}
] | 2019-09-04 | [
[
"Croon",
"Djuna",
""
],
[
"Houtz",
"Rachel",
""
],
[
"Sanz",
"Veronica",
""
]
] | In this paper we explore the possibility of observable gravitational waves as a manifestation of the QCD axion dynamics. In particular, we focus on dynamical axion models which solve the strong CP problem, and include the confinement of a QCD-like gauge group at the TeV scale. We study the resulting chiral symmetry breaking phase transition for models with $N_F=3$ and $N_F=4$ light flavors using the linear sigma model. This model describes the scalar meson spectrum and its interactions, with the diagonal field $\varphi$ as the order parameter. We find that the amplitude of the gravitational wave spectrum depends on the mass of the dynamical axion $\eta'$ via the ratio $m_{\eta'}/m_\varphi$. The resulting spectra may be observed at future mid-range gravitational wave experiments such as AION/MAGIS, DECIGO, and BBO. Moreover, the TeV states can be searched for at colliders and their quantum numbers characterized, providing a unique connection between axion physics, gravitational waves and collider searches. |
hep-ph/0105123 | Tran. Truong | Tran N. Truong | Study of $\gamma\pi \to \pi\pi$ below 1 GeV using Integral Equation
Approach | 26 pages, 10 figures | Phys.Rev. D65 (2002) 056004 | 10.1103/PhysRevD.65.056004 | KEK-TH-755 | hep-ph | null | The scattering of $\gamma \pi \to \pi \pi$ is studied using the axial
anomaly, elastic unitarity, analyticity and crossing symmetry. Using the
technique to derive the Roy's equation, an integral equation for the P-wave
amplitude is obtained in terms of the strong P-wave pion pion phase shifts. Its
solution is obtained numerically by an iteration procedure using the starting
point as the solution of the integral equation of the Muskelshsvilli-Omnes
type. It is, however, ambiguous and depends sensitively on the second
derivative of the P-wave amplitude at $s=m_\pi^2$ which cannot directly be
measured.
| [
{
"created": "Mon, 14 May 2001 15:19:31 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Oct 2001 12:10:16 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Truong",
"Tran N.",
""
]
] | The scattering of $\gamma \pi \to \pi \pi$ is studied using the axial anomaly, elastic unitarity, analyticity and crossing symmetry. Using the technique to derive the Roy's equation, an integral equation for the P-wave amplitude is obtained in terms of the strong P-wave pion pion phase shifts. Its solution is obtained numerically by an iteration procedure using the starting point as the solution of the integral equation of the Muskelshsvilli-Omnes type. It is, however, ambiguous and depends sensitively on the second derivative of the P-wave amplitude at $s=m_\pi^2$ which cannot directly be measured. |
2204.00913 | Scott Chapman | Scott Chapman | Charmonium tetraquarks and pentaquarks or an additional quark? | 5 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Most of the exotic hadrons discovered over the last 20 years fit into the
quark model as normal mesons and baryons if the existence of a seventh flavor
of quark is hypothesized. For the quark to reproduce the mass, spin, parity,
production and decay modes of exotic hadrons, it would have to have a mass of
$\sim$2.8 GeV, a charge of $-\tfrac{1}{3}$, and a W-boson-mediated interaction
with the right-chiral component of the charm quark. The proposed spectrum of
hadrons involving this quark is presented.
| [
{
"created": "Sat, 2 Apr 2022 17:57:00 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Aug 2022 15:01:21 GMT",
"version": "v2"
},
{
"created": "Sat, 27 Aug 2022 20:43:06 GMT",
"version": "v3"
},
{
"created": "Tue, 13 Dec 2022 17:57:57 GMT",
"version": "v4"
},
{
"created": "Thu, 5 Jan 2023 16:43:12 GMT",
"version": "v5"
},
{
"created": "Mon, 8 Jan 2024 17:28:19 GMT",
"version": "v6"
}
] | 2024-01-09 | [
[
"Chapman",
"Scott",
""
]
] | Most of the exotic hadrons discovered over the last 20 years fit into the quark model as normal mesons and baryons if the existence of a seventh flavor of quark is hypothesized. For the quark to reproduce the mass, spin, parity, production and decay modes of exotic hadrons, it would have to have a mass of $\sim$2.8 GeV, a charge of $-\tfrac{1}{3}$, and a W-boson-mediated interaction with the right-chiral component of the charm quark. The proposed spectrum of hadrons involving this quark is presented. |
1609.04908 | Felix Ringer | Zhong-Bo Kang, Felix Ringer, Ivan Vitev | Heavy flavor production in heavy-ion collisions from soft collinear
effective theory | 4 pages, 2 figures, contribution to proceedings of Strangeness in
Quark Matter 2016 | J.Phys.Conf.Ser. 779 (2017), 012029 | 10.1088/1742-6596/779/1/012029 | null | hep-ph hep-ex nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review a new approach to open heavy flavor production in heavy ion
collisions based on Soft Collinear Effective Theory (SCET). We include both
finite heavy quark masses in the SCET Lagrangian and Glauber gluons that
describe the interaction of collinear partons with the hot and dense QCD
medium. From the new effective field theory, we derive massive in-medium
splitting kernels and propose a new framework for including in-medium
interactions consistent with next-to-leading order calculations in QCD. We
present numerical results for the suppression of $D$- and $B$-mesons and
compare to results obtained within the traditional approach to parton energy
loss. We find good agreement when comparing to existing data from the LHC at
$\sqrt{s_{\mathrm{NN}}}=5.02$ TeV and 2.76 TeV.
| [
{
"created": "Fri, 16 Sep 2016 04:56:30 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Dec 2016 05:25:30 GMT",
"version": "v2"
}
] | 2017-02-27 | [
[
"Kang",
"Zhong-Bo",
""
],
[
"Ringer",
"Felix",
""
],
[
"Vitev",
"Ivan",
""
]
] | We review a new approach to open heavy flavor production in heavy ion collisions based on Soft Collinear Effective Theory (SCET). We include both finite heavy quark masses in the SCET Lagrangian and Glauber gluons that describe the interaction of collinear partons with the hot and dense QCD medium. From the new effective field theory, we derive massive in-medium splitting kernels and propose a new framework for including in-medium interactions consistent with next-to-leading order calculations in QCD. We present numerical results for the suppression of $D$- and $B$-mesons and compare to results obtained within the traditional approach to parton energy loss. We find good agreement when comparing to existing data from the LHC at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV and 2.76 TeV. |
1504.07638 | Vicent Mateu | Bahman Dehnadi, Andre H. Hoang, Vicent Mateu | Bottom and Charm Mass Determinations with a Convergence Test | 53 pages, 16 figures, 19 tables; v2 typos fixed, references added,
modification of section 6.3, results for bottom moments and bottom mass
updated, matches published version | null | null | UWThPh-2015-09, LPN15-024 | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present new determinations of the MS-bar charm quark mass using
relativistic QCD sum rules at O(alpha_s^3) from the moments of the vector and
the pseudoscalar current correlators. We use available experimental
measurements from e+e- collisions and lattice simulation results, respectively.
Our analysis of the theoretical uncertainties is based on different
implementations of the perturbative series and on independent variations of the
renormalization scales for the mass and the strong coupling. Taking into
account the resulting set of series to estimate perturbative uncertainties is
crucial, since some ways to treat the perturbative expansion can exhibit
extraordinarily small scale dependence when the two scales are set equal. As an
additional refinement, we address the issue that double scale variation could
overestimate the perturbative uncertainties. We supplement the analysis with a
test that quantifies the convergence rate of each perturbative series by a
single number. We find that this convergence test allows to determine an
overall and average convergence rate that is characteristic for the series
expansions of each moment, and to discard those series for which the
convergence rate is significantly worse. We obtain mc(mc) = 1.288 +- 0.020 GeV
from the vector correlator. The method is also applied to the extraction of the
MS-bar bottom quark mass from the vector correlator. We compute the
experimental moments including a modeling uncertainty associated to the
continuum region where no data is available. We obtain mb(mb) = 4.176 +- 0.023
GeV.
| [
{
"created": "Tue, 28 Apr 2015 20:01:09 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Sep 2015 10:06:04 GMT",
"version": "v2"
}
] | 2015-09-02 | [
[
"Dehnadi",
"Bahman",
""
],
[
"Hoang",
"Andre H.",
""
],
[
"Mateu",
"Vicent",
""
]
] | We present new determinations of the MS-bar charm quark mass using relativistic QCD sum rules at O(alpha_s^3) from the moments of the vector and the pseudoscalar current correlators. We use available experimental measurements from e+e- collisions and lattice simulation results, respectively. Our analysis of the theoretical uncertainties is based on different implementations of the perturbative series and on independent variations of the renormalization scales for the mass and the strong coupling. Taking into account the resulting set of series to estimate perturbative uncertainties is crucial, since some ways to treat the perturbative expansion can exhibit extraordinarily small scale dependence when the two scales are set equal. As an additional refinement, we address the issue that double scale variation could overestimate the perturbative uncertainties. We supplement the analysis with a test that quantifies the convergence rate of each perturbative series by a single number. We find that this convergence test allows to determine an overall and average convergence rate that is characteristic for the series expansions of each moment, and to discard those series for which the convergence rate is significantly worse. We obtain mc(mc) = 1.288 +- 0.020 GeV from the vector correlator. The method is also applied to the extraction of the MS-bar bottom quark mass from the vector correlator. We compute the experimental moments including a modeling uncertainty associated to the continuum region where no data is available. We obtain mb(mb) = 4.176 +- 0.023 GeV. |
2208.05048 | Mohamed Jakha | R. Chahri, S. El Asri, S. Mouslih, M. Jakha, B. Manaut, S. Taj | Relativistic elastic scattering of a muon neutrino by an electron in an
elliptically polarized laser field | 14 pages, 10 figures, 1 Appendix | null | 10.1016/j.physletb.2022.137620 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Within the framework of electroweak theory, we investigate the elastic
scattering process $ e^{-} + \nu_{\mu} \rightarrow e^{-} + \nu_{\mu}$ in the
presence of an intense elliptically polarized laser field. We derive an
analytical expression for the spin-unpolarized differential cross section using
the first Born approximation and the Dirac-Volkov states to describe the
incident and scattered electrons. Our results generalize those found for the
linearly polarized field by Bai \textit{et al.} [Phys. Rev. A \textbf{85},
013402 (2012)] and for the circularly polarized field by El Asri \textit{et
al.} [Phys. Rev. D \textbf{104}, 113001 (2021)]. We find that the differential
cross section is significantly enhanced for linear polarization and reduced for
circular and elliptical polarizations.
| [
{
"created": "Tue, 9 Aug 2022 21:36:01 GMT",
"version": "v1"
}
] | 2022-12-28 | [
[
"Chahri",
"R.",
""
],
[
"Asri",
"S. El",
""
],
[
"Mouslih",
"S.",
""
],
[
"Jakha",
"M.",
""
],
[
"Manaut",
"B.",
""
],
[
"Taj",
"S.",
""
]
] | Within the framework of electroweak theory, we investigate the elastic scattering process $ e^{-} + \nu_{\mu} \rightarrow e^{-} + \nu_{\mu}$ in the presence of an intense elliptically polarized laser field. We derive an analytical expression for the spin-unpolarized differential cross section using the first Born approximation and the Dirac-Volkov states to describe the incident and scattered electrons. Our results generalize those found for the linearly polarized field by Bai \textit{et al.} [Phys. Rev. A \textbf{85}, 013402 (2012)] and for the circularly polarized field by El Asri \textit{et al.} [Phys. Rev. D \textbf{104}, 113001 (2021)]. We find that the differential cross section is significantly enhanced for linear polarization and reduced for circular and elliptical polarizations. |
1208.2212 | Jae Sik Lee | J. S. Lee, M. Carena, J. Ellis, A. Pilaftsis and C. E. M. Wagner | CPsuperH2.3: an Updated Tool for Phenomenology in the MSSM with Explicit
CP Violation | 31 pages, 10 eps figures, 7 tables; H to Z gamma and SM BRs included;
To appear in CPC; Typos in Eq.(A.2) corrected;The program may be obtained
from http://www.hep.man.ac.uk/u/jslee/CPsuperH.html, or by contacting the
first author at jslee@jnu.ac.kr; A comment added after Eq.(15) and a typo in
Eq.(A.4) corrected | null | 10.1016/j.cpc.2012.11.006 | FERMILAB-PUB-12-466-T; ANL-HEP-PR-12-58; EFI-12-20; MAN/HEP/2012/11;
KCL-PH-TH/2012-30; LCTS/2012-15; CERN-PH-TH/2012-195; CNU-HEP-12-01 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We describe the Fortran code CPsuperH2.3, which incorporates the following
updates compared with its predecessor CPsuperH2.0. It implements improved
calculations of the Higgs-boson masses and mixing including stau contributions
and finite threshold effects on the tau-lepton Yukawa coupling. It incorporates
the LEP limits on the processes e^+ e^- to H_i Z, H_i H_j and the CMS limits on
H_i to tau^+ tau^- obtained from 4.6/fb of data at a centre-of-mass energy of 7
TeV. It also includes the decay mode H_i to Z gamma and the Schiff-moment
contributions to the electric dipole moments of Mercury and Radium225, with
several calculational options for the case of Mercury. These additions make
CPsuperH2.3 a suitable tool for analyzing possible CP-violating effects in the
MSSM in the era of the LHC and a new generation of EDM experiments
| [
{
"created": "Fri, 10 Aug 2012 16:29:19 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Oct 2012 06:00:10 GMT",
"version": "v2"
},
{
"created": "Thu, 29 Nov 2012 06:55:41 GMT",
"version": "v3"
},
{
"created": "Wed, 17 Apr 2013 06:01:32 GMT",
"version": "v4"
}
] | 2015-06-11 | [
[
"Lee",
"J. S.",
""
],
[
"Carena",
"M.",
""
],
[
"Ellis",
"J.",
""
],
[
"Pilaftsis",
"A.",
""
],
[
"Wagner",
"C. E. M.",
""
]
] | We describe the Fortran code CPsuperH2.3, which incorporates the following updates compared with its predecessor CPsuperH2.0. It implements improved calculations of the Higgs-boson masses and mixing including stau contributions and finite threshold effects on the tau-lepton Yukawa coupling. It incorporates the LEP limits on the processes e^+ e^- to H_i Z, H_i H_j and the CMS limits on H_i to tau^+ tau^- obtained from 4.6/fb of data at a centre-of-mass energy of 7 TeV. It also includes the decay mode H_i to Z gamma and the Schiff-moment contributions to the electric dipole moments of Mercury and Radium225, with several calculational options for the case of Mercury. These additions make CPsuperH2.3 a suitable tool for analyzing possible CP-violating effects in the MSSM in the era of the LHC and a new generation of EDM experiments |
hep-ph/9905501 | Dongsheng Liu | R. Delbourgo, Dongsheng Liu and M.D. Scadron | Meson PVV Interactions are determined by Quark Loops | 21 pages, Revtex, one figure | Int.J.Mod.Phys.A14:4331-4346,1999 | 10.1142/S0217751X99002049 | UTAS-PHYS-98-24 | hep-ph | null | We show that all abnormal parity three-body meson interactions can be
adequately described by quark loops, evaluated at zero external momentum, with
couplings determined by $U(N_f)$ symmetry. We focus primarily on radiative
meson decays which involve one pseudoscalar. The agreement with experiment for
non-rare decays is surprisingly good and requires very few parameters, namely
the coupling constants $g_{\pi qq}$ and $g_{\rho qq}$ and some mixing angles.
This agreement extends to some three-body decays that are dominated by pion
pairs in a P-wave state.
| [
{
"created": "Thu, 27 May 1999 07:47:05 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Delbourgo",
"R.",
""
],
[
"Liu",
"Dongsheng",
""
],
[
"Scadron",
"M. D.",
""
]
] | We show that all abnormal parity three-body meson interactions can be adequately described by quark loops, evaluated at zero external momentum, with couplings determined by $U(N_f)$ symmetry. We focus primarily on radiative meson decays which involve one pseudoscalar. The agreement with experiment for non-rare decays is surprisingly good and requires very few parameters, namely the coupling constants $g_{\pi qq}$ and $g_{\rho qq}$ and some mixing angles. This agreement extends to some three-body decays that are dominated by pion pairs in a P-wave state. |
1105.1346 | Yacine Mehtar-Tani | Yacine Mehtar-Tani, Konrad Tywoniuk | Jet coherence in QCD media: the antenna radiation spectrum | 15 pages, 2 figures, paper shortened and partly rewritten, references
added, results unchanged | null | 10.1007/JHEP01(2013)031 | LU-TP 11-19 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the radiation of a highly energetic partonic antenna in a colored
state traversing a dense QCD medium. Resumming multiple scatterings of all
involved constituents with the medium we derive the general gluon spectrum
which encompasses both longitudinal color coherence between scattering centers
in the medium, responsible for the well known Landau-Pomeranchuk-Migdal (LPM)
effect, and transverse color coherence between partons inside a jet, leading,
in vacuum, to angular ordering of the parton shower. We discuss shortly the
onset of transverse decoherence which is reached in opaque media. In this
regime, the spectrum consists of independent radiation off the antenna
constituents.
| [
{
"created": "Fri, 6 May 2011 18:11:52 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Jun 2012 12:59:33 GMT",
"version": "v2"
}
] | 2015-05-28 | [
[
"Mehtar-Tani",
"Yacine",
""
],
[
"Tywoniuk",
"Konrad",
""
]
] | We study the radiation of a highly energetic partonic antenna in a colored state traversing a dense QCD medium. Resumming multiple scatterings of all involved constituents with the medium we derive the general gluon spectrum which encompasses both longitudinal color coherence between scattering centers in the medium, responsible for the well known Landau-Pomeranchuk-Migdal (LPM) effect, and transverse color coherence between partons inside a jet, leading, in vacuum, to angular ordering of the parton shower. We discuss shortly the onset of transverse decoherence which is reached in opaque media. In this regime, the spectrum consists of independent radiation off the antenna constituents. |
1112.0219 | Toshihiko Ota | Lorenzo Calibbi, Toshihiko Ota, Yasutaka Takanishi | Light neutralino in the MSSM: An update with the latest LHC results | 4 pages, 4 figures, to appear in the conference proceedings of TAUP
2011, Munich Germany, 5-9 September 2011 | null | 10.1088/1742-6596/375/1/012041 | MPP-2011-144 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the scenario of light neutralino dark matter in the minimal
supersymmetric standard model, which is motivated by the results of some of the
direct detection experiments --- DAMA, CoGENT, and CRESST. We update our
previous analysis with the latest results of the LHC. We show that new LHC
constraints disfavour the parameter region that can reproduce the results of
DAMA and CoGENT.
| [
{
"created": "Thu, 1 Dec 2011 15:56:29 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Jan 2012 11:10:50 GMT",
"version": "v2"
}
] | 2015-06-03 | [
[
"Calibbi",
"Lorenzo",
""
],
[
"Ota",
"Toshihiko",
""
],
[
"Takanishi",
"Yasutaka",
""
]
] | We discuss the scenario of light neutralino dark matter in the minimal supersymmetric standard model, which is motivated by the results of some of the direct detection experiments --- DAMA, CoGENT, and CRESST. We update our previous analysis with the latest results of the LHC. We show that new LHC constraints disfavour the parameter region that can reproduce the results of DAMA and CoGENT. |
2211.02171 | Hesham El Faham | Hesham El Faham, Andrea Giammanco, and Jan Hajer | Exploiting exotic LHC datasets for long-lived new particle searches | v2: version accepted by JHEP. 23 pages with tables and figures | null | 10.1007/JHEP12(2022)123 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Motivated by the expectation that new physics may manifest itself in the form
of very heavy new particles, most of the operation time of the LHC is devoted
to $pp$ collisions at the highest achievable energies and collision rates. The
large collision rates imply tight trigger requirements that include high
thresholds on the final-state particles' transverse momenta $p_{T}$ and an
intrinsic background in the form of particle pileup produced by different
collisions occurring during the same bunch crossing. This strategy is
potentially sub-optimal for several well-motivated new physics models where new
particles are not particularly heavy and can escape the online selection
criteria of the multi-purpose LHC experiments due to their light mass and small
coupling. A solution may be offered by complementary datasets that are
routinely collected by the LHC experiments. These include heavy ion collisions,
low-pileup runs for precision physics, and the so-called 'parking' and
'scouting' datasets. While some of them are motivated by other physics goals,
they all have the usage of mild $p_{T}$ thresholds at the trigger-level in
common. In this study, we assess the relative merits of these datasets for a
representative model whose particular clean signature features long-lived
resonances yielding displaced dimuon vertices. We compare the reach across
those datasets for a simple analysis, simulating LHC data in Run 2 and Run 3
conditions with the Delphes simulation. We show that the scouting and parking
datasets, which afford low-$p_{T}$ trigger thresholds by only using partial
detector information and delaying the event reconstruction, respectively, have
a reach comparable to the standard $pp$ dataset with conventional thresholds.
We also show that heavy ion and low-pileup datasets are far less competitive
for this signature.
| [
{
"created": "Thu, 3 Nov 2022 22:51:44 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Jan 2023 18:29:22 GMT",
"version": "v2"
}
] | 2023-01-03 | [
[
"Faham",
"Hesham El",
""
],
[
"Giammanco",
"Andrea",
""
],
[
"Hajer",
"Jan",
""
]
] | Motivated by the expectation that new physics may manifest itself in the form of very heavy new particles, most of the operation time of the LHC is devoted to $pp$ collisions at the highest achievable energies and collision rates. The large collision rates imply tight trigger requirements that include high thresholds on the final-state particles' transverse momenta $p_{T}$ and an intrinsic background in the form of particle pileup produced by different collisions occurring during the same bunch crossing. This strategy is potentially sub-optimal for several well-motivated new physics models where new particles are not particularly heavy and can escape the online selection criteria of the multi-purpose LHC experiments due to their light mass and small coupling. A solution may be offered by complementary datasets that are routinely collected by the LHC experiments. These include heavy ion collisions, low-pileup runs for precision physics, and the so-called 'parking' and 'scouting' datasets. While some of them are motivated by other physics goals, they all have the usage of mild $p_{T}$ thresholds at the trigger-level in common. In this study, we assess the relative merits of these datasets for a representative model whose particular clean signature features long-lived resonances yielding displaced dimuon vertices. We compare the reach across those datasets for a simple analysis, simulating LHC data in Run 2 and Run 3 conditions with the Delphes simulation. We show that the scouting and parking datasets, which afford low-$p_{T}$ trigger thresholds by only using partial detector information and delaying the event reconstruction, respectively, have a reach comparable to the standard $pp$ dataset with conventional thresholds. We also show that heavy ion and low-pileup datasets are far less competitive for this signature. |
1002.0227 | Andreas Crivellin | Andreas Crivellin and Jennifer Girrbach | Constraining the MSSM sfermion mass matrices with light fermion masses | 12 pages, 10 figures | Phys.Rev.D81:076001,2010 | 10.1103/PhysRevD.81.076001 | TTP10-11 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the finite supersymmetric loop corrections to fermion masses and
mixing matrices in the generic MSSM. In this context the effects of
non-decoupling chirally-enhanced self-energies are studied beyond leading order
in perturbation theory. These NLO corrections are not only necessary for the
renormalization of the CKM matrix to be unitary, they are also numerically
important for the light fermion masses. Focusing on the tri-linear A-terms with
generic flavor-structure we derive very strong bounds on the chirality-changing
mass insertions delta^{f\,LR,RL}_{IJ} by applying 't Hooft's naturalness
criterion. In particular, the NLO corrections to the up quark mass allow us to
constrain the unbounded element delta^{u\,RL}_{13} if at the same time
$\delta^{u\,LR}_{13}$ is unequal to zero. Our result is important for
single-top production at the LHC.
| [
{
"created": "Mon, 1 Feb 2010 16:56:40 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Apr 2010 13:58:37 GMT",
"version": "v2"
}
] | 2015-03-13 | [
[
"Crivellin",
"Andreas",
""
],
[
"Girrbach",
"Jennifer",
""
]
] | We study the finite supersymmetric loop corrections to fermion masses and mixing matrices in the generic MSSM. In this context the effects of non-decoupling chirally-enhanced self-energies are studied beyond leading order in perturbation theory. These NLO corrections are not only necessary for the renormalization of the CKM matrix to be unitary, they are also numerically important for the light fermion masses. Focusing on the tri-linear A-terms with generic flavor-structure we derive very strong bounds on the chirality-changing mass insertions delta^{f\,LR,RL}_{IJ} by applying 't Hooft's naturalness criterion. In particular, the NLO corrections to the up quark mass allow us to constrain the unbounded element delta^{u\,RL}_{13} if at the same time $\delta^{u\,LR}_{13}$ is unequal to zero. Our result is important for single-top production at the LHC. |
hep-ph/0004121 | Oleg V. Pavlovsky | O. V. Pavlovsky | A finite-energy solution in Yang-Mills theory and quantum fluctuations | 7 pages (LaTeX), 2 .eps figures, minor corrections and additions | Phys.Lett. B485 (2000) 151 | 10.1016/S0370-2693(00)00673-0 | null | hep-ph | null | A finite-energy solution of Yang-Mills theory with a nonstandard lagrangian
is provided. Properties of these solution are studied and also a possible
physical interpretation is given.
| [
{
"created": "Thu, 13 Apr 2000 14:53:34 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jul 2000 13:58:33 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Pavlovsky",
"O. V.",
""
]
] | A finite-energy solution of Yang-Mills theory with a nonstandard lagrangian is provided. Properties of these solution are studied and also a possible physical interpretation is given. |
hep-ph/0209078 | Haitham Zaraket | Haitham Zaraket (University of Winnipeg) | $\gamma$-Radiation of thermalized Quark-Gluon-Plasma | 6 pages, 2 ps figures, Contribution to the Proceedings of "Quark
Matter 2002", Nantes, France, 18-24 Jul 2002 | Nucl.Phys. A715 (2003) 713-716 | 10.1016/S0375-9474(02)01473-2 | null | hep-ph | null | Long time ago, photon production was proposed as a probe and a thermometer
for Quark-Gluon Plasma (QGP). However, only recently has the complete
$\alpha_s$ order photon spectrum been obtained. In this paper we give a brief
review of the problematic as well as discuss the ${\cal O}(\alpha_s)$ result.
| [
{
"created": "Fri, 6 Sep 2002 20:55:08 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Zaraket",
"Haitham",
"",
"University of Winnipeg"
]
] | Long time ago, photon production was proposed as a probe and a thermometer for Quark-Gluon Plasma (QGP). However, only recently has the complete $\alpha_s$ order photon spectrum been obtained. In this paper we give a brief review of the problematic as well as discuss the ${\cal O}(\alpha_s)$ result. |
hep-ph/0106265 | National Center for Physics | Fayyazuddin | The decays \bar{B}->\bar{K}D and \bar{B}-> \bar{K}\bar{D} and final
state interactions | 7 pages, RevTeX | null | null | null | hep-ph | null | The decays \bar{B}-> \bar{K}D and \bar{B}-> \bar{K}\bar{D} taking into
account final state interactions are discussed. These decays are described by
four strong phases \delta_0,\delta_1,\bar{\delta}_0,\bar{\delta}_1 (subscripts
0 and 1 refers to I=0 and I=1 final states), one weak phase \gamma and four
real amplitudes. It is argued that strong interaction dynamics implies
\bar{\delta}_1=0,\delta_0=-\delta_1. Rescattering has significant effects on
weak amplitudes. Taking into account, rescattering, we find that direct
CP--violating asymmetry in these decays may lie in the range \mp 0.023\sin
\gamma \leq \QTR{cal}{A}_{1,2}\leq \mp 0.086\sin \gamma.
| [
{
"created": "Sun, 24 Jun 2001 17:43:15 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Fayyazuddin",
"",
""
]
] | The decays \bar{B}-> \bar{K}D and \bar{B}-> \bar{K}\bar{D} taking into account final state interactions are discussed. These decays are described by four strong phases \delta_0,\delta_1,\bar{\delta}_0,\bar{\delta}_1 (subscripts 0 and 1 refers to I=0 and I=1 final states), one weak phase \gamma and four real amplitudes. It is argued that strong interaction dynamics implies \bar{\delta}_1=0,\delta_0=-\delta_1. Rescattering has significant effects on weak amplitudes. Taking into account, rescattering, we find that direct CP--violating asymmetry in these decays may lie in the range \mp 0.023\sin \gamma \leq \QTR{cal}{A}_{1,2}\leq \mp 0.086\sin \gamma. |
hep-ph/0301203 | Marco Aurelio Diaz | Andrew G. Akeroyd and Marco A. Diaz | Searching for a light Fermiophobic Higgs Boson at the Tevatron | 15 pages, including 5 eps-figures | Phys.Rev. D67 (2003) 095007 | 10.1103/PhysRevD.67.095007 | KIAS-P02032, UCCHEP/22-03 | hep-ph | null | We propose new production mechanisms for light fermiophobic Higgs bosons
($h_f$) with suppressed couplings to vector bosons ($V$) at the Fermilab
Tevatron. These mechanisms (e.g. $qq'\to H^\pm h_f$) are complementary to the
conventional process $qq'\to Vh_f$, which suffers from a strong suppression of
$1/\tan^2\beta$ in realistic models with a $h_f$. The new mechanisms extend the
coverage at the Tevatron Run II to the larger $\tan\beta$ region, and offer the
possibility of observing new event topologies with up to 4 photons.
| [
{
"created": "Thu, 23 Jan 2003 14:25:38 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Akeroyd",
"Andrew G.",
""
],
[
"Diaz",
"Marco A.",
""
]
] | We propose new production mechanisms for light fermiophobic Higgs bosons ($h_f$) with suppressed couplings to vector bosons ($V$) at the Fermilab Tevatron. These mechanisms (e.g. $qq'\to H^\pm h_f$) are complementary to the conventional process $qq'\to Vh_f$, which suffers from a strong suppression of $1/\tan^2\beta$ in realistic models with a $h_f$. The new mechanisms extend the coverage at the Tevatron Run II to the larger $\tan\beta$ region, and offer the possibility of observing new event topologies with up to 4 photons. |
0802.3008 | Altug Ozpineci | T. M. Aliev, K. Azizi, A. Ozpineci, M. Savci | Nucleon Electromagnetic Form Factors in QCD | 21 pages, 7 figures | Phys.Rev.D77:114014,2008 | 10.1103/PhysRevD.77.114014 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The nucleon electromagnetic form factors are calculated in light cone QCD sum
rules framework using the most general form of the nucleon interpolating
current. Using two forms of the distribution amplitudes (DA's), predictions for
the form factors are presented and compared with existing experimental data. It
is shown that our results describe remarkably well the existing experimental
data.
| [
{
"created": "Thu, 21 Feb 2008 09:56:32 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Mar 2008 07:44:04 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Aliev",
"T. M.",
""
],
[
"Azizi",
"K.",
""
],
[
"Ozpineci",
"A.",
""
],
[
"Savci",
"M.",
""
]
] | The nucleon electromagnetic form factors are calculated in light cone QCD sum rules framework using the most general form of the nucleon interpolating current. Using two forms of the distribution amplitudes (DA's), predictions for the form factors are presented and compared with existing experimental data. It is shown that our results describe remarkably well the existing experimental data. |
hep-ph/0405223 | Pedro Bicudo | P. Bicudo | The pomeron conjecture and two gluon glueballs | 9 pages, 3 eps figures, uses enclosed frascatiphys.sty; talk at the
Second PANDA Physics Workshop, Laboratori Nazionali di Frascati, March 2004
March 18-19, 2004 | null | null | null | hep-ph | null | In this talk the pomeron conjecture is reviewed and constituent gluon models
are derived. In a simple two-gluon glueball spectrum the pomeron trajectory and
the daughter trajectories are computed. The open problems of two-gluon
glueballs are discussed, including transversality and Yang's theorem, the spin
tensor interactions, the structure of the string and decays. The related
systems of charmed hybrids and of the gluelump are also addressed. To conclude,
different aspects of glueballs that could be measured at PANDA are highlighted.
| [
{
"created": "Sun, 23 May 2004 16:40:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bicudo",
"P.",
""
]
] | In this talk the pomeron conjecture is reviewed and constituent gluon models are derived. In a simple two-gluon glueball spectrum the pomeron trajectory and the daughter trajectories are computed. The open problems of two-gluon glueballs are discussed, including transversality and Yang's theorem, the spin tensor interactions, the structure of the string and decays. The related systems of charmed hybrids and of the gluelump are also addressed. To conclude, different aspects of glueballs that could be measured at PANDA are highlighted. |
hep-ph/9207243 | Lawrence Krauss | Lawrence M. Krauss | COBE, Inflation, and Light Scalars | 13 pages, no figs | null | null | YCTP-P21-92 | hep-ph astro-ph | null | Comparison of theobservedanisotropy with that predicted iadiabaticDM models
suggest that much of thserved signal may be due to long wavelenh gravitational
waves. In inflationary models this requires the generation of tensor
fluctuations to be at least comparable to scalar density fltuations. This i is
feasible, but depends sensitively on the inflaton potential. Alternatively,
isocurvature quantum fluctuations in an axion-like field could produce a
quadrupole anisotropy proportional to the gravitational wave anisotropy,k
independent of the inflaton potential. These could also produce large scale
structure with more power on larger scales than their adiabatic counterparts.
| [
{
"created": "Thu, 16 Jul 1992 02:58:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Krauss",
"Lawrence M.",
""
]
] | Comparison of theobservedanisotropy with that predicted iadiabaticDM models suggest that much of thserved signal may be due to long wavelenh gravitational waves. In inflationary models this requires the generation of tensor fluctuations to be at least comparable to scalar density fltuations. This i is feasible, but depends sensitively on the inflaton potential. Alternatively, isocurvature quantum fluctuations in an axion-like field could produce a quadrupole anisotropy proportional to the gravitational wave anisotropy,k independent of the inflaton potential. These could also produce large scale structure with more power on larger scales than their adiabatic counterparts. |
2210.07846 | Javier Mazzitelli | Stefano Catani, Simone Devoto, Massimiliano Grazzini, Stefan Kallweit,
Javier Mazzitelli, Chiara Savoini | Higgs boson production in association with a top-antitop quark pair in
next-to-next-to leading order QCD | 8 pages, 2 tables, 1 figure. Version published on PRL | null | 10.1103/PhysRevLett.130.111902 | TIF-UNIMI-2022-15, ZU-TH 46/22, MPP-2022-128, PSI-PR-22-30 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The associated production of a Higgs boson with a top-antitop quark pair is a
crucial process at the LHC since it allows for a direct measurement of the
top-quark Yukawa coupling. We present the computation of the radiative
corrections to this process at the next-to-next-to-leading order (NNLO) in QCD
perturbation theory. This is the very first computation for a $2 \to 3$ process
with massive coloured particles at this perturbative order. We develop a soft
Higgs boson approximation for loop amplitudes, which enables us to reliably
quantify the impact of the yet unknown two-loop contribution. At the
centre-of-mass energy $\sqrt{s}=13$ TeV the NNLO corrections increase the
next-to-leading order result for the total cross section by about 4% and lead
to a significant reduction of perturbative uncertainties.
| [
{
"created": "Fri, 14 Oct 2022 14:15:15 GMT",
"version": "v1"
},
{
"created": "Wed, 8 Mar 2023 10:36:08 GMT",
"version": "v2"
}
] | 2023-03-29 | [
[
"Catani",
"Stefano",
""
],
[
"Devoto",
"Simone",
""
],
[
"Grazzini",
"Massimiliano",
""
],
[
"Kallweit",
"Stefan",
""
],
[
"Mazzitelli",
"Javier",
""
],
[
"Savoini",
"Chiara",
""
]
] | The associated production of a Higgs boson with a top-antitop quark pair is a crucial process at the LHC since it allows for a direct measurement of the top-quark Yukawa coupling. We present the computation of the radiative corrections to this process at the next-to-next-to-leading order (NNLO) in QCD perturbation theory. This is the very first computation for a $2 \to 3$ process with massive coloured particles at this perturbative order. We develop a soft Higgs boson approximation for loop amplitudes, which enables us to reliably quantify the impact of the yet unknown two-loop contribution. At the centre-of-mass energy $\sqrt{s}=13$ TeV the NNLO corrections increase the next-to-leading order result for the total cross section by about 4% and lead to a significant reduction of perturbative uncertainties. |
1711.06718 | George De Conto | G. De Conto, A. C. B. Machado, J. P. B. C. de Melo | The Higgs boson in the minimal 3-3-1 model | 36 pages, 12 figures | null | 10.1016/j.physletb.2018.07.056 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we present the mass matrices and mass eigenstates for the
CP-even neutral scalars in the minimal 331 model (m331) and its
self-interactions, showing that the m331 automatically reproduces the Higgs
potential of the Standard Model. We also present a method to generate numerical
solutions for the quarks and leptons masses and their mixings, which we apply
to study FCNC processes, being to calculate the contributions of all exotic
neutral particles of the m331 to the mass differences in meson oscillations.
| [
{
"created": "Fri, 17 Nov 2017 20:29:01 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Nov 2017 13:09:01 GMT",
"version": "v2"
},
{
"created": "Wed, 7 Mar 2018 17:16:12 GMT",
"version": "v3"
}
] | 2018-10-17 | [
[
"De Conto",
"G.",
""
],
[
"Machado",
"A. C. B.",
""
],
[
"de Melo",
"J. P. B. C.",
""
]
] | In this paper we present the mass matrices and mass eigenstates for the CP-even neutral scalars in the minimal 331 model (m331) and its self-interactions, showing that the m331 automatically reproduces the Higgs potential of the Standard Model. We also present a method to generate numerical solutions for the quarks and leptons masses and their mixings, which we apply to study FCNC processes, being to calculate the contributions of all exotic neutral particles of the m331 to the mass differences in meson oscillations. |
1110.5452 | Shigeki Matsumoto | Masahiro Ibe, Shigeki Matsumoto, and Tsutomu T. Yanagida | The GeV-scale dark matter with B-L asymmetry | 16 pages, 2 figures | null | 10.1016/j.physletb.2012.01.032 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | One of important properties of dark matter is its stability. The U(1)$_{\rm
B-L}$ gauge symmetry is the most attractive symmetry to guarantee the
stability. Though the symmetry is expected to be broken at very high energy
scale to account for tiny neutrino masses through the seesaw mechanism, the
residual discrete symmetry of U(1)$_{\rm B-L}$ can stabilize the dark matter
naturally. We prove that, when there is new physics connecting B$-$L charges of
dark matter and standard model particles at the scale between the electroweak
and the U(1)$_{\rm B-L}$ breaking, the mass of dark matter is definitely
predicted to be (5--7)/$Q_{\rm DM}$ GeV ($Q_{DM}$ is the B$-$L charge of dark
matter) independent not only of details of the new physics but also of its
energy scale. We also show two attractive examples. First one is the scalar
dark matter with the B$-$L charge of one, which turns out to be very consistent
with current CoGeNT results. Another one is the fermionic dark matter having
the B$-$L charge of one third, which is also attractive from the viewpoint of
model building.
| [
{
"created": "Tue, 25 Oct 2011 09:35:07 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Ibe",
"Masahiro",
""
],
[
"Matsumoto",
"Shigeki",
""
],
[
"Yanagida",
"Tsutomu T.",
""
]
] | One of important properties of dark matter is its stability. The U(1)$_{\rm B-L}$ gauge symmetry is the most attractive symmetry to guarantee the stability. Though the symmetry is expected to be broken at very high energy scale to account for tiny neutrino masses through the seesaw mechanism, the residual discrete symmetry of U(1)$_{\rm B-L}$ can stabilize the dark matter naturally. We prove that, when there is new physics connecting B$-$L charges of dark matter and standard model particles at the scale between the electroweak and the U(1)$_{\rm B-L}$ breaking, the mass of dark matter is definitely predicted to be (5--7)/$Q_{\rm DM}$ GeV ($Q_{DM}$ is the B$-$L charge of dark matter) independent not only of details of the new physics but also of its energy scale. We also show two attractive examples. First one is the scalar dark matter with the B$-$L charge of one, which turns out to be very consistent with current CoGeNT results. Another one is the fermionic dark matter having the B$-$L charge of one third, which is also attractive from the viewpoint of model building. |
1504.03248 | Jenifer Nebreda | J.A. Carrasco, J. Nebreda, J.R. Pelaez and A.P. Szczepaniak | Dispersive calculation of complex Regge trajectories for the lightest
$f_2$ resonances | 8 pages, 4 figures | null | 10.1016/j.physletb.2015.08.019 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We apply a recently developed dispersive formalism to calculate the Regge
trajectories of the $f_2(1270)$ and $f_2'(1525)$ mesons. Trajectories are
calculated, not fitted to a family of resonances. Assuming that these spin-2
resonances can be treated in the elastic approximation the only input are the
pole position and residue of the resonances. In both cases, the predicted Regge
trajectories are almost real and linear, with slopes in agreement with the
universal value of order 1 GeV$^{-2}$.
| [
{
"created": "Mon, 13 Apr 2015 16:30:49 GMT",
"version": "v1"
}
] | 2015-09-30 | [
[
"Carrasco",
"J. A.",
""
],
[
"Nebreda",
"J.",
""
],
[
"Pelaez",
"J. R.",
""
],
[
"Szczepaniak",
"A. P.",
""
]
] | We apply a recently developed dispersive formalism to calculate the Regge trajectories of the $f_2(1270)$ and $f_2'(1525)$ mesons. Trajectories are calculated, not fitted to a family of resonances. Assuming that these spin-2 resonances can be treated in the elastic approximation the only input are the pole position and residue of the resonances. In both cases, the predicted Regge trajectories are almost real and linear, with slopes in agreement with the universal value of order 1 GeV$^{-2}$. |
1801.10157 | Patrick Schaefers | A. S. Belyaev, P. B. Schaefers, M. C. Thomas | Precise test of Higgs properties via triple Higgs production in VBF at
future colliders | 20 pages, 8 figures | Phys. Rev. D 99, 015030 (2019) | 10.1103/PhysRevD.99.015030 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | For certain classes of Beyond the Standard Model theories, including
composite Higgs models, the coupling of the Higgs to gauge bosons can be
different from the Standard Model one. In this case, the multi-boson production
via vector boson fusion (VBF) can be hugely enhanced in comparison to the SM
production one due to the lack of cancellation in longitudinal vector boson
scattering. Among these processes, triple Higgs boson production in VBF plays a
special role - its enhancement is especially spectacular due to the absence of
background from transversely polarised vector bosons in the final state. While
the rates from $pp\to jjhhh$ production in vector boson fusion are too low at
the LHC and even at future 33 TeV $pp$ colliders, we have found that the 100
TeV $pp$ future circular collider (FCC) has the unique opportunity to probe the
$hVV$ coupling far beyond the LHC sensitivity. We have evaluated the $pp\to
jjhhh$ rates as a function of deviation from the $hVV$ coupling and have found
that the background is much smaller than the signal for observable signal
rates. We also found that the 100 TeV $pp$ FCC can probe the $hVV$ coupling up
to the permille level, which is far beyond the LHC reach. These results
highlight a special role of the $hhh$ VBF production and stress once more the
importance of the 100 TeV $pp$ FCC.
| [
{
"created": "Tue, 30 Jan 2018 19:00:00 GMT",
"version": "v1"
}
] | 2019-01-30 | [
[
"Belyaev",
"A. S.",
""
],
[
"Schaefers",
"P. B.",
""
],
[
"Thomas",
"M. C.",
""
]
] | For certain classes of Beyond the Standard Model theories, including composite Higgs models, the coupling of the Higgs to gauge bosons can be different from the Standard Model one. In this case, the multi-boson production via vector boson fusion (VBF) can be hugely enhanced in comparison to the SM production one due to the lack of cancellation in longitudinal vector boson scattering. Among these processes, triple Higgs boson production in VBF plays a special role - its enhancement is especially spectacular due to the absence of background from transversely polarised vector bosons in the final state. While the rates from $pp\to jjhhh$ production in vector boson fusion are too low at the LHC and even at future 33 TeV $pp$ colliders, we have found that the 100 TeV $pp$ future circular collider (FCC) has the unique opportunity to probe the $hVV$ coupling far beyond the LHC sensitivity. We have evaluated the $pp\to jjhhh$ rates as a function of deviation from the $hVV$ coupling and have found that the background is much smaller than the signal for observable signal rates. We also found that the 100 TeV $pp$ FCC can probe the $hVV$ coupling up to the permille level, which is far beyond the LHC reach. These results highlight a special role of the $hhh$ VBF production and stress once more the importance of the 100 TeV $pp$ FCC. |
0806.3360 | C. A. Dominguez | C. A. Dominguez | Electromagnetic Form Factors of Hadrons in Quantum Field Theories | Invited talk at the Sixth International Conference on Perspectives in
Hadronic Physics, ICTP, Trieste, Italy, May 2008 | AIPConf.Proc.1056:23-30,2008 | 10.1063/1.3013047 | UCT-TP-272/08 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk, recent results are presented of calculations of electromagnetic
form factors of hadrons in the framework of two quantum field theories (QFT),
(a) Dual-Large $N_c$ QCD (Dual-$QCD_\infty$) for the pion, proton, and
$\Delta(1236)$, and (b) the Kroll-Lee-Zumino (KLZ) fully renormalizable Abelian
QFT for the pion form factor. Both theories provide a QFT platform to improve
on naive (tree-level) Vector Meson Dominance (VMD). Dual-$QCD_\infty$ provides
a tree-level improvement by incorporating an infinite number of zero-width
resonances, which can be subsequently shifted from the real axis to account for
the time-like behaviour of the form factors. The renormalizable KLZ model
provides a QFT improvement of VMD in the framework of perturbation theory. Due
to the relative mildness of the $\rho\pi\pi$ coupling, and the size of loop
suppression factors, the perturbative expansion is well defined in spite of
this being a strong coupling theory. Both approaches lead to considerable
improvements of VMD predictions for electromagnetic form factors, in excellent
agreement with data.
| [
{
"created": "Fri, 20 Jun 2008 15:17:57 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Dominguez",
"C. A.",
""
]
] | In this talk, recent results are presented of calculations of electromagnetic form factors of hadrons in the framework of two quantum field theories (QFT), (a) Dual-Large $N_c$ QCD (Dual-$QCD_\infty$) for the pion, proton, and $\Delta(1236)$, and (b) the Kroll-Lee-Zumino (KLZ) fully renormalizable Abelian QFT for the pion form factor. Both theories provide a QFT platform to improve on naive (tree-level) Vector Meson Dominance (VMD). Dual-$QCD_\infty$ provides a tree-level improvement by incorporating an infinite number of zero-width resonances, which can be subsequently shifted from the real axis to account for the time-like behaviour of the form factors. The renormalizable KLZ model provides a QFT improvement of VMD in the framework of perturbation theory. Due to the relative mildness of the $\rho\pi\pi$ coupling, and the size of loop suppression factors, the perturbative expansion is well defined in spite of this being a strong coupling theory. Both approaches lead to considerable improvements of VMD predictions for electromagnetic form factors, in excellent agreement with data. |
hep-ph/0612308 | Seiberg | Ofer Aharony and Nathan Seiberg | Naturalized and simplified gauge mediation | 8 pages, minor changes | JHEP 0702:054,2007 | 10.1088/1126-6708/2007/02/054 | null | hep-ph hep-th | null | Following recent developments in model building we construct a simple,
natural and controllable model of gauge-mediated supersymmetry breaking.
| [
{
"created": "Fri, 22 Dec 2006 15:02:07 GMT",
"version": "v1"
},
{
"created": "Thu, 11 Jan 2007 19:30:23 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Aharony",
"Ofer",
""
],
[
"Seiberg",
"Nathan",
""
]
] | Following recent developments in model building we construct a simple, natural and controllable model of gauge-mediated supersymmetry breaking. |
0711.2902 | C. Hanhart | Yu. S. Kalashnikova, A. E. Kudryavtsev, A. V. Nefediev, J.
Haidenbauer, and C. Hanhart | Comment on "Once more about the KK molecule approach to the light
scalars" | RevTeX, 4 pages. Version as published in comment section of
Phys.Rev.D plus discussion of reply to this comment contained in
arXiv:0806.2993 | Phys.Rev.D78:058501,2008 | 10.1103/PhysRevD.78.058501 | FZJ-IKP-TH-2007-29 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this manuscript we comment on the criticism raised recently by Achasov and
Kiselev [Phys. Rev. D 76, 077501 (2007)] on our work on the radiative decays
phi to gamma a_0/f_0 [Eur. Phys. J. A 24, 437 (2005)]. Specifically, we
demonstrate that their criticism relies on results that violate
gauge-invariance and is therefore invalid.
| [
{
"created": "Mon, 19 Nov 2007 11:48:22 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Oct 2008 09:02:29 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Kalashnikova",
"Yu. S.",
""
],
[
"Kudryavtsev",
"A. E.",
""
],
[
"Nefediev",
"A. V.",
""
],
[
"Haidenbauer",
"J.",
""
],
[
"Hanhart",
"C.",
""
]
] | In this manuscript we comment on the criticism raised recently by Achasov and Kiselev [Phys. Rev. D 76, 077501 (2007)] on our work on the radiative decays phi to gamma a_0/f_0 [Eur. Phys. J. A 24, 437 (2005)]. Specifically, we demonstrate that their criticism relies on results that violate gauge-invariance and is therefore invalid. |
hep-ph/0606051 | Thomas G. Rizzo | Thomas G. Rizzo | Noncommutative Inspired Black Holes in Extra Dimensions | 30 pages, 12 figures; slight text modifications and references added | JHEP 0609 (2006) 021 | 10.1088/1126-6708/2006/09/021 | SLAC-PUB-11864 | hep-ph gr-qc hep-th | null | In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci
(NSS) presented an interesting model for a noncommutative inspired,
Schwarzschild-like black hole solution in 4-dimensions. The essential effect of
having noncommutative co-ordinates in this approach is to smear out matter
distributions on a scale associated with the turn-on of noncommutativity which
was taken to be near the 4-d Planck mass. In particular, NSS took this smearing
to be essentially Gaussian. This energy scale is sufficiently large that in 4-d
such effects may remain invisible indefinitely. Extra dimensional models which
attempt to address the gauge hierarchy problem, however, allow for the
possibility that the effective fundamental scale may not be far from $\sim$ 1
TeV, an energy regime that will soon be probed by experiments at both the LHC
and ILC. In this paper we generalize the NSS model to the case where flat,
toroidally compactified extra dimensions are accessible at the Terascale and
examine the resulting modifications in black hole properties due to the
existence of noncommutativity. We show that while many of the
noncommutativity-induced black hole features found in 4-d by NSS persist, in
some cases there can be significant modifications due the presence of extra
dimensions. We also demonstrate that the essential features of this approach
are not particularly sensitive to the Gaussian nature of the smearing employed
by NSS.
| [
{
"created": "Mon, 5 Jun 2006 17:28:13 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Jun 2006 16:08:41 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Rizzo",
"Thomas G.",
""
]
] | In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS took this smearing to be essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from $\sim$ 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the Terascale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We also demonstrate that the essential features of this approach are not particularly sensitive to the Gaussian nature of the smearing employed by NSS. |
1404.1003 | P. S. Bhupal Dev | P. S. Bhupal Dev, Peter Millington, Apostolos Pilaftsis, Daniele
Teresi | Flavour Covariant Transport Equations: an Application to Resonant
Leptogenesis | 109 pages, 14 figures, 5 tables; typos corrected; final published
version | Nucl. Phys. B 886 (2014) 569-664 | 10.1016/j.nuclphysb.2014.06.020 | MAN/HEP/2014/01, IPPP/14/20, DCPT/14/40 | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a fully flavour-covariant formalism for transport phenomena, by
deriving Markovian master equations that describe the time-evolution of
particle number densities in a statistical ensemble with arbitrary flavour
content. As an application of this general formalism, we study flavour effects
in a scenario of resonant leptogenesis (RL) and obtain the flavour-covariant
evolution equations for heavy-neutrino and lepton number densities. This
provides a complete and unified description of RL, capturing three distinct
physical phenomena: (i) the resonant mixing between the heavy-neutrino states,
(ii) coherent oscillations between different heavy-neutrino flavours, and (iii)
quantum decoherence effects in the charged-lepton sector. To illustrate the
importance of this formalism, we numerically solve the flavour-covariant rate
equations for a minimal RL model and show that the total lepton asymmetry can
be enhanced by up to one order of magnitude, as compared to that obtained from
flavour-diagonal or partially flavour off-diagonal rate equations. Thus, the
viable RL model parameter space is enlarged, thereby enhancing further the
prospects of probing a common origin of neutrino masses and the baryon
asymmetry in the Universe at the LHC, as well as in low-energy experiments
searching for lepton flavour and number violation. The key new ingredients in
our flavour-covariant formalism are rank-4 rate tensors, which are required for
the consistency of our flavour-mixing treatment, as shown by an explicit
calculation of the relevant transition amplitudes by generalizing the optical
theorem. We also provide a geometric and physical interpretation of the
heavy-neutrino degeneracy limits in the minimal RL scenario. Finally, we
comment on the consistency of various suggested forms for the heavy-neutrino
self-energy regulator in the lepton-number conserving limit.
| [
{
"created": "Thu, 3 Apr 2014 16:53:11 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Apr 2014 18:03:25 GMT",
"version": "v2"
},
{
"created": "Mon, 23 Jun 2014 16:51:36 GMT",
"version": "v3"
},
{
"created": "Fri, 25 Jul 2014 14:59:52 GMT",
"version": "v4"
}
] | 2015-04-28 | [
[
"Dev",
"P. S. Bhupal",
""
],
[
"Millington",
"Peter",
""
],
[
"Pilaftsis",
"Apostolos",
""
],
[
"Teresi",
"Daniele",
""
]
] | We present a fully flavour-covariant formalism for transport phenomena, by deriving Markovian master equations that describe the time-evolution of particle number densities in a statistical ensemble with arbitrary flavour content. As an application of this general formalism, we study flavour effects in a scenario of resonant leptogenesis (RL) and obtain the flavour-covariant evolution equations for heavy-neutrino and lepton number densities. This provides a complete and unified description of RL, capturing three distinct physical phenomena: (i) the resonant mixing between the heavy-neutrino states, (ii) coherent oscillations between different heavy-neutrino flavours, and (iii) quantum decoherence effects in the charged-lepton sector. To illustrate the importance of this formalism, we numerically solve the flavour-covariant rate equations for a minimal RL model and show that the total lepton asymmetry can be enhanced by up to one order of magnitude, as compared to that obtained from flavour-diagonal or partially flavour off-diagonal rate equations. Thus, the viable RL model parameter space is enlarged, thereby enhancing further the prospects of probing a common origin of neutrino masses and the baryon asymmetry in the Universe at the LHC, as well as in low-energy experiments searching for lepton flavour and number violation. The key new ingredients in our flavour-covariant formalism are rank-4 rate tensors, which are required for the consistency of our flavour-mixing treatment, as shown by an explicit calculation of the relevant transition amplitudes by generalizing the optical theorem. We also provide a geometric and physical interpretation of the heavy-neutrino degeneracy limits in the minimal RL scenario. Finally, we comment on the consistency of various suggested forms for the heavy-neutrino self-energy regulator in the lepton-number conserving limit. |
1506.08688 | Riccardo Torre | Andrea Thamm, Riccardo Torre, Andrea Wulzer | A composite Heavy Vector Triplet in the ATLAS di-boson excess | 6 pages, 1 table, 1 figure; v2: typos corrected, references added | Phys. Rev. Lett. 115, 221802 (2015) | 10.1103/PhysRevLett.115.221802 | DFPD-2015/TH/16, MITP/15-044 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Composite vector resonances in the triplet of the SM SU$(2)_{L}$ gauge group
are a universal prediction of "natural" new physics models involving a new
strongly-interacting sector and are therefore among the most plausible new
particles that the LHC could discover. We consider the possibility that one
such triplet could account for the ATLAS excess in the invariant-mass spectrum
of boson-tagged jets and we assess the compatibility of this hypothesis with
all other relevant resonance searches. We find that the hypothesis is not
excluded and that the predicted signal is close to the expected sensitivity of
several channels, some of which show an upper fluctuation of the observed limit
while others do not. An accurate study of the signal compatibility with these
fluctuations could only be performed by the ATLAS and CMS collaborations.
| [
{
"created": "Mon, 29 Jun 2015 15:41:22 GMT",
"version": "v1"
},
{
"created": "Thu, 9 Jul 2015 12:15:39 GMT",
"version": "v2"
}
] | 2015-12-02 | [
[
"Thamm",
"Andrea",
""
],
[
"Torre",
"Riccardo",
""
],
[
"Wulzer",
"Andrea",
""
]
] | Composite vector resonances in the triplet of the SM SU$(2)_{L}$ gauge group are a universal prediction of "natural" new physics models involving a new strongly-interacting sector and are therefore among the most plausible new particles that the LHC could discover. We consider the possibility that one such triplet could account for the ATLAS excess in the invariant-mass spectrum of boson-tagged jets and we assess the compatibility of this hypothesis with all other relevant resonance searches. We find that the hypothesis is not excluded and that the predicted signal is close to the expected sensitivity of several channels, some of which show an upper fluctuation of the observed limit while others do not. An accurate study of the signal compatibility with these fluctuations could only be performed by the ATLAS and CMS collaborations. |
hep-ph/0406006 | Troy Andre | Troy C. Andre | Radiative Corrections to K^0_{l3} Decays | Accepted in Annals of Physics; 16 pages, 8 figures; v3 contains minor
text changes | AnnalsPhys.322:2518-2544,2007 | 10.1016/j.aop.2006.11.014 | EFI-04-17 | hep-ph | null | We calculate the long-distance radiative corrections \delta^e_{LD} and
\delta^{\mu}_{LD} to the K^0 -> \pi^- e^+ \nu_e and the K^0 -> pi^- \mu^+
\nu_{\mu} decay rates. This analysis includes contributions to the
long-distance radiative corrections from outside the kinematically-allowed
three-body Dalitz region and tests the sensitivity of the radiative corrections
to the hadronic K-pi form factors. A program, KLOR, was written to numerically
evaluate the radiative corrections and to generate Monte Carlo events for
experimental acceptance studies. The K^0_{e3} and the K^0_{\mu 3} long-distance
radiative correction parameters are determined to be (1.3 +/- 0.3)% and (1.9
+/- 0.3)%, respectively. We also present predictions for the fraction of
radiative K^0_{l3} events satisfying various requirements on final-state photon
kinematics.
| [
{
"created": "Tue, 1 Jun 2004 18:43:55 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Jun 2004 19:28:03 GMT",
"version": "v2"
},
{
"created": "Sat, 2 Dec 2006 02:43:10 GMT",
"version": "v3"
}
] | 2009-09-29 | [
[
"Andre",
"Troy C.",
""
]
] | We calculate the long-distance radiative corrections \delta^e_{LD} and \delta^{\mu}_{LD} to the K^0 -> \pi^- e^+ \nu_e and the K^0 -> pi^- \mu^+ \nu_{\mu} decay rates. This analysis includes contributions to the long-distance radiative corrections from outside the kinematically-allowed three-body Dalitz region and tests the sensitivity of the radiative corrections to the hadronic K-pi form factors. A program, KLOR, was written to numerically evaluate the radiative corrections and to generate Monte Carlo events for experimental acceptance studies. The K^0_{e3} and the K^0_{\mu 3} long-distance radiative correction parameters are determined to be (1.3 +/- 0.3)% and (1.9 +/- 0.3)%, respectively. We also present predictions for the fraction of radiative K^0_{l3} events satisfying various requirements on final-state photon kinematics. |
hep-ph/0210145 | Piotr H. Chankowski | A.J. Buras (Munich), P.H. Chankowski (Warsaw), J. Rosiek (Munich and
Warsaw) and L. Slawianowska (Warsaw) | $\Delta M_{d,s}$, $B^0_{d,s}\to\mu^+\mu^-$ and $B\to X_s\gamma$ in
Supersymmetry at Large $\tan\beta$ | 86 pages, 10 postscript figures. Minor changes, some references
added. Version to be published in Nuclear Physics B | Nucl.Phys.B659:3,2003 | 10.1016/S0550-3213(03)00190-1 | TUM-HEP-479/02, IFT-02/34 | hep-ph | null | We present an effective Lagrangian formalism for the calculation of flavour
changing neutral and charged scalar currents in weak decays including
$SU(2)\times U(1)$ symmetry breaking effects and the effects of the electroweak
couplings $g_1$ and $g_2$. We apply this formalism to the MSSM with large
$\tan\beta$ with the CKM matrix as the only source of flavour violation, heavy
supersymmetric particles and light Higgs bosons. We give analytic formulae for
the neutral and charged Higgs boson couplings to quarks including large
$\tan\beta$ resummed corrections in the $SU(2) \times U(1)$ limit and
demonstrate that these formulae can only be used for a semi-quantitative
analysis. In particular they overestimate the effects of large $\tan\beta$
resummed corrections. We give also improved analytic formulae that reproduce
the numerical results of the full approach within $5-10%$. We present for the
first time the predictions for the branching ratios $B^0_{s,d}\to \mu^+\mu^-$
and the $B^0_{d,s}-\bar B^0_{d,s}$ mass differences $\Delta M_{d,s}$ that
include simultaneously the resummed large $\tan\beta$ corrections, $SU(2)\times
U(1)$ breaking effects and the effects of the electroweak couplings. We perform
an anatomy of the correlation between the increase of the rates of the decays
$B^0_{s,d}\to\mu^+\mu^-$ and the suppression of $\Delta M_s$, that for large
$\tan\beta$ are caused by the enhanced flavour changing neutral Higgs couplings
to down quarks. We take into account the constraint from $B\to X_s \gamma$
clarifying some points in the calculation of the large $\tan\beta$ enhanced
corrections to this decay.
| [
{
"created": "Wed, 9 Oct 2002 15:10:29 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Mar 2003 14:33:48 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Buras",
"A. J.",
"",
"Munich"
],
[
"Chankowski",
"P. H.",
"",
"Warsaw"
],
[
"Rosiek",
"J.",
"",
"Munich and\n Warsaw"
],
[
"Slawianowska",
"L.",
"",
"Warsaw"
]
] | We present an effective Lagrangian formalism for the calculation of flavour changing neutral and charged scalar currents in weak decays including $SU(2)\times U(1)$ symmetry breaking effects and the effects of the electroweak couplings $g_1$ and $g_2$. We apply this formalism to the MSSM with large $\tan\beta$ with the CKM matrix as the only source of flavour violation, heavy supersymmetric particles and light Higgs bosons. We give analytic formulae for the neutral and charged Higgs boson couplings to quarks including large $\tan\beta$ resummed corrections in the $SU(2) \times U(1)$ limit and demonstrate that these formulae can only be used for a semi-quantitative analysis. In particular they overestimate the effects of large $\tan\beta$ resummed corrections. We give also improved analytic formulae that reproduce the numerical results of the full approach within $5-10%$. We present for the first time the predictions for the branching ratios $B^0_{s,d}\to \mu^+\mu^-$ and the $B^0_{d,s}-\bar B^0_{d,s}$ mass differences $\Delta M_{d,s}$ that include simultaneously the resummed large $\tan\beta$ corrections, $SU(2)\times U(1)$ breaking effects and the effects of the electroweak couplings. We perform an anatomy of the correlation between the increase of the rates of the decays $B^0_{s,d}\to\mu^+\mu^-$ and the suppression of $\Delta M_s$, that for large $\tan\beta$ are caused by the enhanced flavour changing neutral Higgs couplings to down quarks. We take into account the constraint from $B\to X_s \gamma$ clarifying some points in the calculation of the large $\tan\beta$ enhanced corrections to this decay. |
hep-ph/0302127 | Michael Eides | Michael I. Eides (University of Kentucky, USA, and Petersburg Nuclear
Physics Institute, Russia), Howard Grotch (University of Kentucky, USA), and
Valery A. Shelyuto (D. I. Mendeleev Institute of Metrology, Russia) | Three-Loop Radiative-Recoil Corrections to Hyperfine Splitting in
Muonium | 27 pages, 6 figures, 7 tables | Phys.Rev. D67 (2003) 113003 | 10.1103/PhysRevD.67.113003 | UK/03-01 | hep-ph physics.atom-ph | null | We calculate three-loop radiative-recoil corrections to hyperfine splitting
in muonium generated by the diagrams with the first order electron and muon
polarization loop insertions in graphs with two exchanged photons. These
corrections are enhanced by the large logarithm of the electron-muon mass
ratio. The leading logarithm squared contribution was obtained a long time ago.
Here we calculate the single-logarithmic and nonlogarithmic contributions. We
previously calculated the three-loop radiative-recoil corrections generated by
two-loop polarization insertions in the exchanged photons. The current paper
therefore concludes calculation of all three-loop radiative-recoil corrections
to hyperfine splitting in muonium generated by diagrams with closed fermion
loop insertions in the exchanged photons. The new results obtained here improve
the theory of hyperfine splitting, and affect the value of the electron-muon
mass ratio extracted from experimental data on the muonium hyperfine splitting.
| [
{
"created": "Sun, 16 Feb 2003 00:34:13 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Eides",
"Michael I.",
"",
"University of Kentucky, USA, and Petersburg Nuclear\n Physics Institute, Russia"
],
[
"Grotch",
"Howard",
"",
"University of Kentucky, USA"
],
[
"Shelyuto",
"Valery A.",
"",
"D. I. Mendeleev Institute of Metrology, Russia"
]
] | We calculate three-loop radiative-recoil corrections to hyperfine splitting in muonium generated by the diagrams with the first order electron and muon polarization loop insertions in graphs with two exchanged photons. These corrections are enhanced by the large logarithm of the electron-muon mass ratio. The leading logarithm squared contribution was obtained a long time ago. Here we calculate the single-logarithmic and nonlogarithmic contributions. We previously calculated the three-loop radiative-recoil corrections generated by two-loop polarization insertions in the exchanged photons. The current paper therefore concludes calculation of all three-loop radiative-recoil corrections to hyperfine splitting in muonium generated by diagrams with closed fermion loop insertions in the exchanged photons. The new results obtained here improve the theory of hyperfine splitting, and affect the value of the electron-muon mass ratio extracted from experimental data on the muonium hyperfine splitting. |
1404.5207 | Yandong Liu | Zhaofeng Kang, Jinmian Li, Tianjun Li, Yandong Liu, Guo-Zhu Ning | Light Doubly Charged Higgs Boson via the $WW^*$ Channel at LHC | 23 pages, 4 figures, typos fixed, references added, EPJC version | null | 10.1140/epjc/s10052-015-3774-1 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The doubly charged Higgs bosons $H^{\pm\pm}$ searches at the Large Hadron
Collider (LHC) have been studied extensively and strong bound is available for
$H^{\pm\pm}$ dominantly decaying into a pair of same-sign di-leptons. In this
paper we point out that there is a large cavity in the light $H^{\pm\pm}$ mass
region left unexcluded. In particular, $H^{\pm\pm}$ can dominantly decay into
$WW$ or $WW^*$ (For instance, in the type-II seesaw mechanism the triplet
acquires a vacuum expectation value around 1 GeV.), and then it is found that
$H^{\pm\pm}$ with mass even below $2m_W$ remains untouched by the current
collider searches. Searching for such a $H^{\pm\pm}$ at the LHC is the topic of
this paper. We perform detailed signal and background simulation, especially
including the non-prompt $t\bar{t}$ background which is the dominant one
nevertheless ignored before. We show that such $H^{\pm\pm}$ should be
observable at the 14 TeV LHC with 10-30 fb$^{-1}$ integrated luminosity.
| [
{
"created": "Mon, 21 Apr 2014 14:23:58 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Jul 2014 06:43:04 GMT",
"version": "v2"
},
{
"created": "Tue, 17 Nov 2015 15:22:37 GMT",
"version": "v3"
}
] | 2016-01-27 | [
[
"Kang",
"Zhaofeng",
""
],
[
"Li",
"Jinmian",
""
],
[
"Li",
"Tianjun",
""
],
[
"Liu",
"Yandong",
""
],
[
"Ning",
"Guo-Zhu",
""
]
] | The doubly charged Higgs bosons $H^{\pm\pm}$ searches at the Large Hadron Collider (LHC) have been studied extensively and strong bound is available for $H^{\pm\pm}$ dominantly decaying into a pair of same-sign di-leptons. In this paper we point out that there is a large cavity in the light $H^{\pm\pm}$ mass region left unexcluded. In particular, $H^{\pm\pm}$ can dominantly decay into $WW$ or $WW^*$ (For instance, in the type-II seesaw mechanism the triplet acquires a vacuum expectation value around 1 GeV.), and then it is found that $H^{\pm\pm}$ with mass even below $2m_W$ remains untouched by the current collider searches. Searching for such a $H^{\pm\pm}$ at the LHC is the topic of this paper. We perform detailed signal and background simulation, especially including the non-prompt $t\bar{t}$ background which is the dominant one nevertheless ignored before. We show that such $H^{\pm\pm}$ should be observable at the 14 TeV LHC with 10-30 fb$^{-1}$ integrated luminosity. |
hep-ph/0005281 | Shi-Lin Zhu | Shi-Lin Zhu, S.J. Puglia, B.R. Holstein and M. J. Ramsey-Musolf | Chiral Symmetry and the Parity-Violating $NN\pi$ Yukawa Coupling | RevTex, 26 pages + 5 PS figures | Phys.Rev. D63 (2001) 033006 | 10.1103/PhysRevD.63.033006 | null | hep-ph hep-ex hep-lat nucl-ex nucl-th | null | We construct the complete SU(2) parity-violating (PV) $\pi, N, \Delta$
interaction Lagrangian with one derivative, and calculate the chiral
corrections to the PV Yukawa $NN\pi$ coupling constant $h_\pi$ through ${\cal
O}(1/\Lambda_\chi^3)$ in the leading order of heavy baryon expansion. We
discuss the relationship between the renormalized $\hpi$, the measured value of
$\hpi$, and the corresponding quantity calculated microscopically from the
Standard Model four-quark PV interaction.
| [
{
"created": "Sun, 28 May 2000 22:56:34 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Zhu",
"Shi-Lin",
""
],
[
"Puglia",
"S. J.",
""
],
[
"Holstein",
"B. R.",
""
],
[
"Ramsey-Musolf",
"M. J.",
""
]
] | We construct the complete SU(2) parity-violating (PV) $\pi, N, \Delta$ interaction Lagrangian with one derivative, and calculate the chiral corrections to the PV Yukawa $NN\pi$ coupling constant $h_\pi$ through ${\cal O}(1/\Lambda_\chi^3)$ in the leading order of heavy baryon expansion. We discuss the relationship between the renormalized $\hpi$, the measured value of $\hpi$, and the corresponding quantity calculated microscopically from the Standard Model four-quark PV interaction. |
hep-ph/0007312 | Maxim Kotsky | V.S. Fadin, R. Fiore, M.I. Kotsky | The Compatibility of the Gluon Reggeization with the s-channel Unitarity | 11 pages | Phys.Lett. B494 (2000) 100-108 | 10.1016/S0370-2693(00)01161-8 | UNICAL-TH 00/2, Budker INP 2000-62 | hep-ph | null | Recently the non-forward BFKL kernel for interaction of two Reggeized gluons
in the antisymmetric colour octet state in the $t$-channel was obtained in the
next-to-leading order. It gives the possibility to check in this order the
bootstrap condition for this kernel, appearing as the requirement of the
compatibility of gluon Reggeization with the $s$-channel unitarity.
| [
{
"created": "Thu, 27 Jul 2000 09:31:21 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Fadin",
"V. S.",
""
],
[
"Fiore",
"R.",
""
],
[
"Kotsky",
"M. I.",
""
]
] | Recently the non-forward BFKL kernel for interaction of two Reggeized gluons in the antisymmetric colour octet state in the $t$-channel was obtained in the next-to-leading order. It gives the possibility to check in this order the bootstrap condition for this kernel, appearing as the requirement of the compatibility of gluon Reggeization with the $s$-channel unitarity. |
1410.0356 | Kuver Sinha | Archana Anandakrishnan, Bibhushan Shakya, Kuver Sinha | Dark Matter at the Pseudoscalar Higgs Resonance in the pMSSM and SUSY
GUTs | 14 pages, 6 figures | Phys. Rev. D 91, 035029 (2015) | 10.1103/PhysRevD.91.035029 | OHSTPY-HEP-T-14-005, MCTP-14-35 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study dark matter at the MSSM pseudoscalar Higgs resonance (A-funnel),
which is one of the few remaining MSSM thermal dark matter candidates in the
$100-1000$ GeV range safe from direct detection constraints. To illustrate the
various factors at play, this study is performed in two contrasting set-ups: a
bottom-up phenomenological MSSM (pMSSM) approach that allows significant
freedom, and the top-down, highly constrained Yukawa unified $SO(10)$ GUT
model. In the pMSSM, for $\mu > 0$, the entire parameter space lies above the
coherent neutrino background and mostly within reach of XENON1T and LZ, while
blind spots exist at $m_A\,> \, 800\,$GeV for $\mu < 0$; the strongest
constraints come from $A/H \rightarrow \tau \tau$ searches at the LHC. For
Yukawa unified models, the confluence of $B_s \rightarrow \mu^+ \mu^-$
constraints, fits to the bottom quark and Higgs masses, and gluino mass bounds
from the LHC result in a prediction: realizing the pseudoscalar resonance
$requires$ gaugino mass non-universality, with a mass ratio that is determined
to within a small range.
| [
{
"created": "Wed, 1 Oct 2014 20:00:02 GMT",
"version": "v1"
}
] | 2015-03-05 | [
[
"Anandakrishnan",
"Archana",
""
],
[
"Shakya",
"Bibhushan",
""
],
[
"Sinha",
"Kuver",
""
]
] | We study dark matter at the MSSM pseudoscalar Higgs resonance (A-funnel), which is one of the few remaining MSSM thermal dark matter candidates in the $100-1000$ GeV range safe from direct detection constraints. To illustrate the various factors at play, this study is performed in two contrasting set-ups: a bottom-up phenomenological MSSM (pMSSM) approach that allows significant freedom, and the top-down, highly constrained Yukawa unified $SO(10)$ GUT model. In the pMSSM, for $\mu > 0$, the entire parameter space lies above the coherent neutrino background and mostly within reach of XENON1T and LZ, while blind spots exist at $m_A\,> \, 800\,$GeV for $\mu < 0$; the strongest constraints come from $A/H \rightarrow \tau \tau$ searches at the LHC. For Yukawa unified models, the confluence of $B_s \rightarrow \mu^+ \mu^-$ constraints, fits to the bottom quark and Higgs masses, and gluino mass bounds from the LHC result in a prediction: realizing the pseudoscalar resonance $requires$ gaugino mass non-universality, with a mass ratio that is determined to within a small range. |
hep-ph/0401141 | Chun-Khiang Chua | Hai-Yang Cheng and Chun-Khiang Chua | Covariant Light-Front Approach for B to K* gamma, K_1 gamma, K*_2 gamma
Decays | 18 pages, 2 figures; to be published in Phys. Rev. D | Phys.Rev.D69:094007,2004; Erratum-ibid.D81:059901,2010 | 10.1103/PhysRevD.69.094007 10.1103/PhysRevD.81.059901 | null | hep-ph hep-ex | null | Exclusive radiative B decays, B to K* gamma, K_1(1270) gamma, K_1(1400) gamma
and K*_2(1430) gamma, are studied in the framework of a covariant light-front
quark model. The tensor form factor T_1(q^2) at q^2=0, which is relevant to the
decay B to K* gamma, is found to be 0.24, substantially smaller than what
expected from the conventional light-front model or light-cone sum rules.
Taking into account the sizable next-to-leading order (NLO) corrections, the
calculated branching ratio of B to K* gamma agrees with experiment, while most
of the existing models predict too large B to K* gamma compared to the data.
The relative strength of B to K_1(1270) gamma and B to K_1(1400) gamma rates is
very sensitive to the sign of the K_1(1270)-K_1(1400) mixing angle. Contrary to
the other models in which K_1(1270) gamma and K_1(1400) gamma rates are
predicted to be comparable, it is found that one of them is strongly suppressed
owing to a large cancellation between two different form factor terms. The
calculated branching ratio of B to K*_2 gamma is in a good agreement with
experiment and this may imply the smallness of NLO corrections to this
radiative decay mode.
| [
{
"created": "Tue, 20 Jan 2004 07:20:12 GMT",
"version": "v1"
},
{
"created": "Thu, 26 Feb 2004 00:57:21 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Cheng",
"Hai-Yang",
""
],
[
"Chua",
"Chun-Khiang",
""
]
] | Exclusive radiative B decays, B to K* gamma, K_1(1270) gamma, K_1(1400) gamma and K*_2(1430) gamma, are studied in the framework of a covariant light-front quark model. The tensor form factor T_1(q^2) at q^2=0, which is relevant to the decay B to K* gamma, is found to be 0.24, substantially smaller than what expected from the conventional light-front model or light-cone sum rules. Taking into account the sizable next-to-leading order (NLO) corrections, the calculated branching ratio of B to K* gamma agrees with experiment, while most of the existing models predict too large B to K* gamma compared to the data. The relative strength of B to K_1(1270) gamma and B to K_1(1400) gamma rates is very sensitive to the sign of the K_1(1270)-K_1(1400) mixing angle. Contrary to the other models in which K_1(1270) gamma and K_1(1400) gamma rates are predicted to be comparable, it is found that one of them is strongly suppressed owing to a large cancellation between two different form factor terms. The calculated branching ratio of B to K*_2 gamma is in a good agreement with experiment and this may imply the smallness of NLO corrections to this radiative decay mode. |
0709.1022 | Youichi Yamada | Youichi Yamada | b\to s\nu\bar{\nu} decay in the MSSM: Implication of b\to s\gamma at
large tan beta | 17 pages, references added, figures refined | Phys.Rev.D77:014025,2008 | 10.1103/PhysRevD.77.014025 | TU-796 | hep-ph | null | The decay $b\to s\nu\bar{\nu}$ is discussed in the minimal supersymmetric
standard model with general flavor mixing for squarks, at large $\tan\beta$. In
this case, in addition to the chargino loop contributions which were analyzed
in previously studies, $\tan\beta$-enhanced contributions from the gluino and
charged Higgs boson loops might become sizable compared with the standard model
contribution, at least in principle. However, it is demonstrated that the
experimental bounds on the new physics contributions to the radiative decay
$b\to s\gamma$ should strongly constrain these contributions to $b\to
s\nu\bar{\nu}$, especially on the gluino contribution. We also briefly comment
on a possible constraint from the $B_s\to\mu^+\mu^-$ decay.
| [
{
"created": "Fri, 7 Sep 2007 08:43:53 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Jan 2008 09:59:42 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Yamada",
"Youichi",
""
]
] | The decay $b\to s\nu\bar{\nu}$ is discussed in the minimal supersymmetric standard model with general flavor mixing for squarks, at large $\tan\beta$. In this case, in addition to the chargino loop contributions which were analyzed in previously studies, $\tan\beta$-enhanced contributions from the gluino and charged Higgs boson loops might become sizable compared with the standard model contribution, at least in principle. However, it is demonstrated that the experimental bounds on the new physics contributions to the radiative decay $b\to s\gamma$ should strongly constrain these contributions to $b\to s\nu\bar{\nu}$, especially on the gluino contribution. We also briefly comment on a possible constraint from the $B_s\to\mu^+\mu^-$ decay. |
1606.06986 | Sergio Pastor | Pablo F. de Salas, Sergio Pastor | Relic neutrino decoupling with flavour oscillations revisited | 19 pages, 6 figures | JCAP 07 (2016) 051 | 10.1088/1475-7516/2016/07/051 | IFIC/16-10, TTK-16-23 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the decoupling process of neutrinos in the early universe in the
presence of three-flavour oscillations. The evolution of the neutrino spectra
is found by solving the corresponding momentum-dependent kinetic equations for
the neutrino density matrix, including for the first time the proper collision
integrals for both diagonal and off-diagonal elements. This improved
calculation modifies the evolution of the off-diagonal elements of the neutrino
density matrix and changes the deviation from equilibrium of the frozen
neutrino spectra. However, it does not vary the contribution of neutrinos to
the cosmological energy density in the form of radiation, usually expressed in
terms of the effective number of neutrinos, N_eff. We find a value of
N_eff=3.045, in agreement with previous theoretical calculations and consistent
with the latest analysis of Planck data. This result does not depend on the
ordering of neutrino masses. We also consider the effect of non-standard
neutrino-electron interactions (NSI), predicted in many theoretical models
where neutrinos acquire mass. For two sets of NSI parameters allowed by present
data, we find that N_eff can be reduced down to 3.040 or enhanced up to 3.059.
| [
{
"created": "Wed, 22 Jun 2016 15:29:30 GMT",
"version": "v1"
}
] | 2016-07-29 | [
[
"de Salas",
"Pablo F.",
""
],
[
"Pastor",
"Sergio",
""
]
] | We study the decoupling process of neutrinos in the early universe in the presence of three-flavour oscillations. The evolution of the neutrino spectra is found by solving the corresponding momentum-dependent kinetic equations for the neutrino density matrix, including for the first time the proper collision integrals for both diagonal and off-diagonal elements. This improved calculation modifies the evolution of the off-diagonal elements of the neutrino density matrix and changes the deviation from equilibrium of the frozen neutrino spectra. However, it does not vary the contribution of neutrinos to the cosmological energy density in the form of radiation, usually expressed in terms of the effective number of neutrinos, N_eff. We find a value of N_eff=3.045, in agreement with previous theoretical calculations and consistent with the latest analysis of Planck data. This result does not depend on the ordering of neutrino masses. We also consider the effect of non-standard neutrino-electron interactions (NSI), predicted in many theoretical models where neutrinos acquire mass. For two sets of NSI parameters allowed by present data, we find that N_eff can be reduced down to 3.040 or enhanced up to 3.059. |
hep-ph/0301009 | Antonio Lopez Maroto | J.A.R. Cembranos, A. Dobado, A. L. Maroto | Phenomenological implications of brane world scenarios with low tension | 8 pages, LaTeX uses aipproc, 2 figures. Talk given by A. Dobado in
the X Mexican School of Particles and Fields, Playa del Carmen, Mexico, 2002 | AIPConf.Proc.670:235-242,2003 | 10.1063/1.1594340 | null | hep-ph | null | The recent proposal of theories with compactified large extra dimensions is
reviewed. We pay especial attention to brane world models with low tension
where the only relevant degrees of freedom at low energies are the Standard
Model (SM) particles and the branons, which are transversal brane oscillations.
By using an effective Lagrangian, we study some phenomenological consequences
of these scenarios in a model independent way.
| [
{
"created": "Fri, 3 Jan 2003 10:56:11 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Cembranos",
"J. A. R.",
""
],
[
"Dobado",
"A.",
""
],
[
"Maroto",
"A. L.",
""
]
] | The recent proposal of theories with compactified large extra dimensions is reviewed. We pay especial attention to brane world models with low tension where the only relevant degrees of freedom at low energies are the Standard Model (SM) particles and the branons, which are transversal brane oscillations. By using an effective Lagrangian, we study some phenomenological consequences of these scenarios in a model independent way. |
0801.2415 | Gudrid Moortgat-Pick | G. Moortgat-Pick, I.R. Bailey, D.P. Barber, E. Baynham, A. Birch, T.
Bradshaw, A. Brummitt, S. Carr, J.A. Clarke, P. Cooke, J.B. Dainton, T.
Hartin, Y. Ivanyushenkov, L.J. Jenner, A. Lintern, L.I. Malysheva, O.B.
Malyshev, J. Rochford, S. Riemann, A. Sch\"alicke, P. Schmid, D.J. Scott, A.
Ushakov, L. Zang | Challenge of polarized beams at future colliders | 5 pages, contribution to the proceedings of EPS07 | J.Phys.Conf.Ser.110:112004,2008 | 10.1088/1742-6596/110/11/112004 | COCKCROFT-07-22, IPPP/07/72, DCPT/07/144 | hep-ph | null | A short overview about the potential of polarized beams at future colliders
is given. In particular the baseline design for polarized beams at the ILC is
presented and the physics case for polarized $e^-$ and $e^+$ is discussed. In
order to fulfil the precision requirements spin tracking from the source to the
interaction point is needed. Updates concerning the theoretical calculations as
well as their implementation in simulation codes are reported.
| [
{
"created": "Wed, 16 Jan 2008 01:28:09 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Moortgat-Pick",
"G.",
""
],
[
"Bailey",
"I. R.",
""
],
[
"Barber",
"D. P.",
""
],
[
"Baynham",
"E.",
""
],
[
"Birch",
"A.",
""
],
[
"Bradshaw",
"T.",
""
],
[
"Brummitt",
"A.",
""
],
[
"Carr",
"S.",
""
],
[
"Clarke",
"J. A.",
""
],
[
"Cooke",
"P.",
""
],
[
"Dainton",
"J. B.",
""
],
[
"Hartin",
"T.",
""
],
[
"Ivanyushenkov",
"Y.",
""
],
[
"Jenner",
"L. J.",
""
],
[
"Lintern",
"A.",
""
],
[
"Malysheva",
"L. I.",
""
],
[
"Malyshev",
"O. B.",
""
],
[
"Rochford",
"J.",
""
],
[
"Riemann",
"S.",
""
],
[
"Schälicke",
"A.",
""
],
[
"Schmid",
"P.",
""
],
[
"Scott",
"D. J.",
""
],
[
"Ushakov",
"A.",
""
],
[
"Zang",
"L.",
""
]
] | A short overview about the potential of polarized beams at future colliders is given. In particular the baseline design for polarized beams at the ILC is presented and the physics case for polarized $e^-$ and $e^+$ is discussed. In order to fulfil the precision requirements spin tracking from the source to the interaction point is needed. Updates concerning the theoretical calculations as well as their implementation in simulation codes are reported. |
hep-ph/9905404 | David London | D. London, N. Sinha and R. Sinha | Can One Measure the Weak Phase of a Penguin Diagram? | 20 pages, no figures | Phys.Rev. D60 (1999) 074020 | 10.1103/PhysRevD.60.074020 | UdeM-GPP-TH-99-58, IMSc-99/-5/18 | hep-ph | null | The b -> d penguin amplitude receives contributions from internal u, c and
t-quarks. We show that it is impossible to measure the weak phase of any of
these penguin contributions without theoretical input. However, it is possible
to obtain the weak phase if one makes a single assumption involving the
hadronic parameters. With such an assumption, one can test for the presence of
new physics in the b -> d flavour-changing neutral current by comparing the
weak phase of B_d^0-{\bar B}_d^0 mixing with that of the t-quark contribution
to the b -> d penguin.
| [
{
"created": "Wed, 19 May 1999 16:39:10 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"London",
"D.",
""
],
[
"Sinha",
"N.",
""
],
[
"Sinha",
"R.",
""
]
] | The b -> d penguin amplitude receives contributions from internal u, c and t-quarks. We show that it is impossible to measure the weak phase of any of these penguin contributions without theoretical input. However, it is possible to obtain the weak phase if one makes a single assumption involving the hadronic parameters. With such an assumption, one can test for the presence of new physics in the b -> d flavour-changing neutral current by comparing the weak phase of B_d^0-{\bar B}_d^0 mixing with that of the t-quark contribution to the b -> d penguin. |
2402.18901 | Ulas Ozdem | U. \"Ozdem | Electromagnetic properties of $\Omega_{c}^0$ resonances via light-cone
QCD | 12 pages, 3 tables, 1 figure | null | null | null | hep-ph hep-ex hep-lat | http://creativecommons.org/licenses/by/4.0/ | We systematically study the electromagnetic properties of controversial
states whose internal structure is not elucidated and we try to offer a
different point of view to unravel the internal structure of these states.
Inspired by the $\Omega_c$ states observed by the LHCb Collaboration, we study
the electromagnetic properties of the $\Omega_c$ states as the compact
diquark-diquark-antiquark pentaquarks with both $J^P = \frac{1}{2}^-$ and $J^P
= \frac{3}{2}^-$ in the context of the QCD light-cone sum rule model. From the
obtained numerical results, we conclude that the magnetic dipole moments of the
$\Omega_c$ states can reflect their inner structures, which can be used to
distinguish their spin-parity quantum numbers. Measuring the magnetic moment of
the $\Omega_c$ states in future experimental facilities can be very helpful for
understanding the internal organization and identifying the quantum numbers of
these states.
| [
{
"created": "Thu, 29 Feb 2024 06:55:05 GMT",
"version": "v1"
},
{
"created": "Thu, 2 May 2024 10:09:10 GMT",
"version": "v2"
},
{
"created": "Tue, 6 Aug 2024 06:17:00 GMT",
"version": "v3"
}
] | 2024-08-07 | [
[
"Özdem",
"U.",
""
]
] | We systematically study the electromagnetic properties of controversial states whose internal structure is not elucidated and we try to offer a different point of view to unravel the internal structure of these states. Inspired by the $\Omega_c$ states observed by the LHCb Collaboration, we study the electromagnetic properties of the $\Omega_c$ states as the compact diquark-diquark-antiquark pentaquarks with both $J^P = \frac{1}{2}^-$ and $J^P = \frac{3}{2}^-$ in the context of the QCD light-cone sum rule model. From the obtained numerical results, we conclude that the magnetic dipole moments of the $\Omega_c$ states can reflect their inner structures, which can be used to distinguish their spin-parity quantum numbers. Measuring the magnetic moment of the $\Omega_c$ states in future experimental facilities can be very helpful for understanding the internal organization and identifying the quantum numbers of these states. |
hep-ph/0410303 | Per Osland | B. K. Gjelsten, D. J. Miller, P. Osland | Measurement of SUSY masses via cascade decays for SPS 1a | 57 pages, several figures, some of which should be viewed/printed in
colour. v2: version accepted for publication | JHEP 0412:003,2004 | 10.1088/1126-6708/2004/12/003 | ATL-PHYS-2004-029, Edinburgh 2004/12 | hep-ph hep-ex | null | If R-parity conserving supersymmetry exists below the TeV-scale, new
particles will be produced and decay in cascades at the LHC. The lightest
supersymmetric particle will escape the detectors, thereby complicating the
full reconstruction of the decay chains. In this paper we expand on existing
methods for determining the masses of the particles in the cascade from
endpoints of kinematical distributions. We perform scans in the mSUGRA
parameter space to delimit the region where this method is applicable. From the
examination of theoretical distributions for a wide selection of mass scenarios
it is found that caution must be exerted when equating the theoretical
endpoints with the experimentally obtainable ones. We provide analytic formulae
for the masses in terms of the endpoints most readily available. Complications
due to the composite nature of the endpoint expressions are discussed in
relation to the detailed analysis of two points on the SPS~1a line. Finally we
demonstrate how a Linear Collider measurement can improve dramatically on the
precision of the masses obtained.
| [
{
"created": "Fri, 22 Oct 2004 10:30:51 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Jan 2005 20:34:14 GMT",
"version": "v2"
}
] | 2009-04-13 | [
[
"Gjelsten",
"B. K.",
""
],
[
"Miller",
"D. J.",
""
],
[
"Osland",
"P.",
""
]
] | If R-parity conserving supersymmetry exists below the TeV-scale, new particles will be produced and decay in cascades at the LHC. The lightest supersymmetric particle will escape the detectors, thereby complicating the full reconstruction of the decay chains. In this paper we expand on existing methods for determining the masses of the particles in the cascade from endpoints of kinematical distributions. We perform scans in the mSUGRA parameter space to delimit the region where this method is applicable. From the examination of theoretical distributions for a wide selection of mass scenarios it is found that caution must be exerted when equating the theoretical endpoints with the experimentally obtainable ones. We provide analytic formulae for the masses in terms of the endpoints most readily available. Complications due to the composite nature of the endpoint expressions are discussed in relation to the detailed analysis of two points on the SPS~1a line. Finally we demonstrate how a Linear Collider measurement can improve dramatically on the precision of the masses obtained. |
hep-ph/9810259 | Matthias Jamin | M. Jamin and A. Pich | Bottom quark mass from QCD sum rules for the Upsilon system | 4 pages, 1 figure, Invited talk at the Euroconference QCD'98,
Montpellier, July 1998 | Nucl.Phys.Proc.Suppl.74:300-303,1999 | 10.1016/S0920-5632(99)00182-6 | HD-THEP-98-50, FTUV/98-75, IFIC/98-76 | hep-ph | null | The talk presents an update of the bottom quark mass determination from QCD
moment sum rules for the Upsilon system by the authors. Employing the MS_bar
scheme, we find m_b(m_b) = 4.19 +- 0.06 GeV. The differences to our previous
analysis will be discussed and we comment on the determination of the pole mass
for the bottom quark.
| [
{
"created": "Tue, 6 Oct 1998 11:11:20 GMT",
"version": "v1"
}
] | 2011-01-25 | [
[
"Jamin",
"M.",
""
],
[
"Pich",
"A.",
""
]
] | The talk presents an update of the bottom quark mass determination from QCD moment sum rules for the Upsilon system by the authors. Employing the MS_bar scheme, we find m_b(m_b) = 4.19 +- 0.06 GeV. The differences to our previous analysis will be discussed and we comment on the determination of the pole mass for the bottom quark. |
1411.3300 | Kuang-Ta Chao | H.S. Shao, H. Han, Y.Q. Ma, C. Meng, Y.J. Zhang, K.T. Chao | Yields and polarizations of prompt $\jpsi$ and $\psits$ production in
hadronic collisions | Version published in JHEP, 17 pages, 8 figures | JHEP05 (2015) 103 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We give predictions of $\jpsi$ and $\psits$ yields and polarizations in
prompt production at hadron colliders based on non-relativistic QCD
factorization formula. We calculate short-distance coefficients of all
important color-octet intermediate channels as well as color-singlet channels
up to $\mathcal{O}(\alpha_S^4)$, i.e. next-to-leading order in $\alpha_S$. For
prompt $\jpsi$ production, we also take into account feeddown contributions
from $\chi_{cJ}$(J=0,1,2) and $\psits$ decays. Color-singlet long-distance
matrix elements (LDMEs) are estimated by using potential model, and color-octet
LDMEs are extracted by fitting the Tevatron yield data only. The predictions
are satisfactory for both yields and polarizations of prompt $\jpsi$ and prompt
$\psits$ production at the Tevatron and the LHC. In particular, we find our
predictions for polarizations of prompt $\jpsi$ production have only a little
difference from our previous predictions for polarizations of direct $\jpsi$
production.
| [
{
"created": "Wed, 12 Nov 2014 20:06:19 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Jun 2015 11:18:24 GMT",
"version": "v2"
}
] | 2015-06-02 | [
[
"Shao",
"H. S.",
""
],
[
"Han",
"H.",
""
],
[
"Ma",
"Y. Q.",
""
],
[
"Meng",
"C.",
""
],
[
"Zhang",
"Y. J.",
""
],
[
"Chao",
"K. T.",
""
]
] | We give predictions of $\jpsi$ and $\psits$ yields and polarizations in prompt production at hadron colliders based on non-relativistic QCD factorization formula. We calculate short-distance coefficients of all important color-octet intermediate channels as well as color-singlet channels up to $\mathcal{O}(\alpha_S^4)$, i.e. next-to-leading order in $\alpha_S$. For prompt $\jpsi$ production, we also take into account feeddown contributions from $\chi_{cJ}$(J=0,1,2) and $\psits$ decays. Color-singlet long-distance matrix elements (LDMEs) are estimated by using potential model, and color-octet LDMEs are extracted by fitting the Tevatron yield data only. The predictions are satisfactory for both yields and polarizations of prompt $\jpsi$ and prompt $\psits$ production at the Tevatron and the LHC. In particular, we find our predictions for polarizations of prompt $\jpsi$ production have only a little difference from our previous predictions for polarizations of direct $\jpsi$ production. |
1706.06402 | Kasper Lang{\ae}ble | Frederik F. Hansen, Tadeusz Janowski, Kasper Langaeble, Robert B.
Mann, Francesco Sannino, Tom G. Steele, Zhi-Wei Wang | Phase structure of complete asymptotically free SU($N_c$) theories with
quarks and scalar quarks | 37 pages, 16 figures, including several appendices | Phys. Rev. D 97, 065014 (2018) | 10.1103/PhysRevD.97.065014 | CP3-Origins-2017-022 DNRF90, CERN-TH-2017-133 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We determine the phase diagram of complete asymptotically free SU($N_c$)
gauge theories featuring $N_s$ complex scalars and $N_f$ Dirac quarks
transforming according to the fundamental representation of the gauge group.
The analysis is performed at the maximum known order in perturbation theory. We
unveil a very rich dynamics and associated phase structure. Intriguingly we
discover that the complete asymptotically free conditions guarantee that the
infrared dynamics displays long distance conformality, and in a regime when
perturbation theory is applicable. We conclude our analysis by determining the
quantum corrected potential of the theory and summarising the possible patterns
of radiative symmetry breaking. These theories are of potential
phenomenological interest as either elementary or composite ultraviolet finite
extensions of the Standard Model.
| [
{
"created": "Tue, 20 Jun 2017 13:10:51 GMT",
"version": "v1"
}
] | 2018-03-28 | [
[
"Hansen",
"Frederik F.",
""
],
[
"Janowski",
"Tadeusz",
""
],
[
"Langaeble",
"Kasper",
""
],
[
"Mann",
"Robert B.",
""
],
[
"Sannino",
"Francesco",
""
],
[
"Steele",
"Tom G.",
""
],
[
"Wang",
"Zhi-Wei",
""
]
] | We determine the phase diagram of complete asymptotically free SU($N_c$) gauge theories featuring $N_s$ complex scalars and $N_f$ Dirac quarks transforming according to the fundamental representation of the gauge group. The analysis is performed at the maximum known order in perturbation theory. We unveil a very rich dynamics and associated phase structure. Intriguingly we discover that the complete asymptotically free conditions guarantee that the infrared dynamics displays long distance conformality, and in a regime when perturbation theory is applicable. We conclude our analysis by determining the quantum corrected potential of the theory and summarising the possible patterns of radiative symmetry breaking. These theories are of potential phenomenological interest as either elementary or composite ultraviolet finite extensions of the Standard Model. |
1112.3956 | Andreas Papaefstathiou | Andreas Papaefstathiou and Kazuki Sakurai | Determining the helicity structure of third generation resonances | 40 pages, 36 figures. Version accepted for publication by JHEP | null | 10.1007/JHEP06(2012)069 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine methods that have been proposed for determining the helicity
structure of decays of new resonances to third generation quarks and/or
leptons. We present analytical and semi-analytical predictions and assess the
applicability of the relevant variables in realistic reconstruction scenarios
using Monte Carlo-generated events, including the effects of QCD radiation and
multiple parton interactions, combinatoric ambiguities and fast detector
simulation.
| [
{
"created": "Fri, 16 Dec 2011 21:00:00 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Jul 2012 15:53:02 GMT",
"version": "v2"
}
] | 2012-07-03 | [
[
"Papaefstathiou",
"Andreas",
""
],
[
"Sakurai",
"Kazuki",
""
]
] | We examine methods that have been proposed for determining the helicity structure of decays of new resonances to third generation quarks and/or leptons. We present analytical and semi-analytical predictions and assess the applicability of the relevant variables in realistic reconstruction scenarios using Monte Carlo-generated events, including the effects of QCD radiation and multiple parton interactions, combinatoric ambiguities and fast detector simulation. |
2406.15506 | Bernanda Telalovic | Bernanda Telalovic, Damiano F.G. Fiorillo, Pablo Mart\'inez-Mirav\'e,
Edoardo Vitagliano, Mauricio Bustamante | The next galactic supernova can uncover mass and couplings of particles
decaying to neutrinos | 38 pages, 7 figures | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Many particles predicted by extensions of the Standard Model feature
interactions with neutrinos, e.g., Majoron-like bosons $\phi$. If the mass of
$\phi$ is larger than about 10 keV, they can be produced abundantly in the core
of the next galactic core-collapse supernova through neutrino coalescence, and
leave it with energies of around 100 MeV. Their subsequent decay to high-energy
neutrinos and anti-neutrinos provides a distinctive signature at Earth. Ongoing
and planned neutrino and dark matter experiments allow us to reconstruct the
energy, flavor, and time of arrival of these high-energy neutrinos. For the
first time, we show that these measurements can help pinpointing the mass of
$\phi$ and its couplings to neutrinos of different flavor. Our results can be
generalized in a straightforward manner to other hypothetical feebly
interacting particles, like novel gauge bosons or heavy neutral leptons, that
decay into neutrinos.
| [
{
"created": "Wed, 19 Jun 2024 18:00:15 GMT",
"version": "v1"
}
] | 2024-06-25 | [
[
"Telalovic",
"Bernanda",
""
],
[
"Fiorillo",
"Damiano F. G.",
""
],
[
"Martínez-Miravé",
"Pablo",
""
],
[
"Vitagliano",
"Edoardo",
""
],
[
"Bustamante",
"Mauricio",
""
]
] | Many particles predicted by extensions of the Standard Model feature interactions with neutrinos, e.g., Majoron-like bosons $\phi$. If the mass of $\phi$ is larger than about 10 keV, they can be produced abundantly in the core of the next galactic core-collapse supernova through neutrino coalescence, and leave it with energies of around 100 MeV. Their subsequent decay to high-energy neutrinos and anti-neutrinos provides a distinctive signature at Earth. Ongoing and planned neutrino and dark matter experiments allow us to reconstruct the energy, flavor, and time of arrival of these high-energy neutrinos. For the first time, we show that these measurements can help pinpointing the mass of $\phi$ and its couplings to neutrinos of different flavor. Our results can be generalized in a straightforward manner to other hypothetical feebly interacting particles, like novel gauge bosons or heavy neutral leptons, that decay into neutrinos. |
hep-ph/9407346 | Alexander Ignatiev | A.Yu.Ignatiev and G.C.Joshi | Non-Zero Electric Charge of the Neutrino and the Solar Neutrino Problem | 29 pages, UM-P/94-73, RCHEP-94/21, in REVTEX | Phys.Rev.D51:2411-2420,1995 | 10.1103/PhysRevD.51.2411 | null | hep-ph astro-ph | null | It has recently been shown that the neutrino can have non-zero electric
charge in a number of gauge theories, including the Minimal Standard Model.
Assuming non-zero neutrino charge, we develop a new approach to the solar
neutrino problem. The key idea is that the charged neutrinos will be deflected
by the Lorentz force while they are crossing the solar magnetic fields. Such a
deflection will result in the anisotropy of the solar neutrino flux. Because of
this anisotropy, the solar neutrino flux registered on earth can be reduced as
compared to the Standard Solar Model prediction. The mechanism is purely
classical and does not require neutrino oscillations, spin-flip or neutrino
decay. We discuss qualitatively the consequences of our scenario for present
and future solar neutrino experiments as well as differences between our
mechanism and other proposed solutions.
| [
{
"created": "Thu, 21 Jul 1994 03:04:07 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Ignatiev",
"A. Yu.",
""
],
[
"Joshi",
"G. C.",
""
]
] | It has recently been shown that the neutrino can have non-zero electric charge in a number of gauge theories, including the Minimal Standard Model. Assuming non-zero neutrino charge, we develop a new approach to the solar neutrino problem. The key idea is that the charged neutrinos will be deflected by the Lorentz force while they are crossing the solar magnetic fields. Such a deflection will result in the anisotropy of the solar neutrino flux. Because of this anisotropy, the solar neutrino flux registered on earth can be reduced as compared to the Standard Solar Model prediction. The mechanism is purely classical and does not require neutrino oscillations, spin-flip or neutrino decay. We discuss qualitatively the consequences of our scenario for present and future solar neutrino experiments as well as differences between our mechanism and other proposed solutions. |
1003.1041 | Alexander Krikun | Alexander Krikun | Four-point correlator of vector currents and electric current
susceptibility in holographic QCD | 14 pages, 1 figure (v2: references added, typos corrected) | Phys.Lett.B692:36-42,2010 | 10.1016/j.physletb.2010.07.009 | ITEP-TH-13/10 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we calculate the four-point correlation function of vector quark
currents of QCD via holographic QCD model. Computing the correlator we take
into account the exchange of vector and axial vector bosons and dilaton in the
bulk. The result is used for calculation of the two-point correlator of
electromagnetic currents in external magnetic field at zero momentum, related
to RHIC experiments, chiral magnetic effect and lattice study. At zero
temperature we find this quantity to be loosely connected with chiral symmetry
breaking and strongly dependent on the confinement properties. Some features of
the AdS/QCD models are also discussed.
| [
{
"created": "Thu, 4 Mar 2010 13:44:17 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Mar 2010 11:22:12 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Krikun",
"Alexander",
""
]
] | In this work we calculate the four-point correlation function of vector quark currents of QCD via holographic QCD model. Computing the correlator we take into account the exchange of vector and axial vector bosons and dilaton in the bulk. The result is used for calculation of the two-point correlator of electromagnetic currents in external magnetic field at zero momentum, related to RHIC experiments, chiral magnetic effect and lattice study. At zero temperature we find this quantity to be loosely connected with chiral symmetry breaking and strongly dependent on the confinement properties. Some features of the AdS/QCD models are also discussed. |
0710.4365 | Weizhen Deng | Fang-Yong Zou, Xiao-Lin Chen, Wei-Zhen Deng | The Three-body Force and the Tetraquark Interpretation of Light Scalar
Mesons | null | Chin.Phys.C32:515-520,2008 | 10.1088/1674-1137/32/7/002 | null | hep-ph | null | We study the possible tetraquark interpretation of light scalar meson states
$a_0(980)$, $f_0(980)$, $\kappa$, $\sigma$ within the framework of the
non-relativistic potential model. The wave functions of tetraquark states are
obtained in a space spanned by multiple Gaussian functions. We find that the
mass spectra of the light scalar mesons can be well accommodated in the
tetraquark picture if we introduce a three-body quark interaction in the quark
model. Using the obtained multiple Gaussian wave functions, the decay constants
of tetraquarks are also calculated within the ``fall apart'' mechanism.
| [
{
"created": "Wed, 24 Oct 2007 00:57:31 GMT",
"version": "v1"
}
] | 2011-03-17 | [
[
"Zou",
"Fang-Yong",
""
],
[
"Chen",
"Xiao-Lin",
""
],
[
"Deng",
"Wei-Zhen",
""
]
] | We study the possible tetraquark interpretation of light scalar meson states $a_0(980)$, $f_0(980)$, $\kappa$, $\sigma$ within the framework of the non-relativistic potential model. The wave functions of tetraquark states are obtained in a space spanned by multiple Gaussian functions. We find that the mass spectra of the light scalar mesons can be well accommodated in the tetraquark picture if we introduce a three-body quark interaction in the quark model. Using the obtained multiple Gaussian wave functions, the decay constants of tetraquarks are also calculated within the ``fall apart'' mechanism. |
1601.00586 | Yuji Omura | P. Ko, Yuji Omura, Chaehyun Yu | Diphoton Excess at 750 GeV in leptophobic U(1)$^\prime$ model inspired
by $E_6$ GUT | 21 pages, 4 figures. Published version | JHEP1604 (2016) 098 | 10.1007/JHEP04(2016)098 | KIAS-16002 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the 750 GeV diphoton excess at the LHC@13TeV in the framework of
leptophobic U(1)$^\prime$ model inspired by $E_6$ grand unified theory (GUT).
In this model, the Standard Model (SM) chiral fermions carry charges under
extra U(1)$^\prime$ gauge symmetry which is spontaneously broken by a
U(1)$^\prime$-charged singlet scalar ($\Phi$). In addition, extra quarks and
leptons are introduced to achieve the anomaly-free conditions, which is a
natural consequence of the assumed $E_6$ GUT. These new fermions are vectorlike
under the SM gauge group but chiral under new U(1)$^\prime$, and their masses
come entirely from the nonzero vacuum expectation value of $\Phi$ through the
Yukawa interactions. Then, the CP-even scalar $h_\Phi$ from $\Phi$ can be
produced at the LHC by the gluon fusion and decay to the diphoton via the
one-loop diagram involving the extra quarks and leptons, and can be identified
as the origin of diphoton excess at 750 GeV. In this model, $h_\Phi$ can decay
into a pair of dark matter particles as well as a pair of scalar bosons,
thereby a few tens of the decay width may be possible.
| [
{
"created": "Mon, 4 Jan 2016 17:47:42 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Apr 2016 07:13:04 GMT",
"version": "v2"
}
] | 2016-04-21 | [
[
"Ko",
"P.",
""
],
[
"Omura",
"Yuji",
""
],
[
"Yu",
"Chaehyun",
""
]
] | We discuss the 750 GeV diphoton excess at the LHC@13TeV in the framework of leptophobic U(1)$^\prime$ model inspired by $E_6$ grand unified theory (GUT). In this model, the Standard Model (SM) chiral fermions carry charges under extra U(1)$^\prime$ gauge symmetry which is spontaneously broken by a U(1)$^\prime$-charged singlet scalar ($\Phi$). In addition, extra quarks and leptons are introduced to achieve the anomaly-free conditions, which is a natural consequence of the assumed $E_6$ GUT. These new fermions are vectorlike under the SM gauge group but chiral under new U(1)$^\prime$, and their masses come entirely from the nonzero vacuum expectation value of $\Phi$ through the Yukawa interactions. Then, the CP-even scalar $h_\Phi$ from $\Phi$ can be produced at the LHC by the gluon fusion and decay to the diphoton via the one-loop diagram involving the extra quarks and leptons, and can be identified as the origin of diphoton excess at 750 GeV. In this model, $h_\Phi$ can decay into a pair of dark matter particles as well as a pair of scalar bosons, thereby a few tens of the decay width may be possible. |
hep-ph/0401083 | Franco Buccella | F. Buccella and P. Sorba | Narrow width pentaquarks | 11 pages | Mod.Phys.Lett. A19 (2004) 1547 | 10.1142/S0217732304014835 | DSF-43/2003 | hep-ph | null | A general study of pentaquarks built with four quarks in a L=1 state and an
antiquark in S-wave shows that several of such states are forbidden by a
selection rule, which holds in the limit of flavour symmetry, to decay into a
baryon and a meson final state. We identify the most promising \bar{10}
multiplet for the classification of the Theta^+ and Xi^{--} particles recently
discovered with the prediction of a narrow width for both of them.
| [
{
"created": "Mon, 12 Jan 2004 14:32:19 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Buccella",
"F.",
""
],
[
"Sorba",
"P.",
""
]
] | A general study of pentaquarks built with four quarks in a L=1 state and an antiquark in S-wave shows that several of such states are forbidden by a selection rule, which holds in the limit of flavour symmetry, to decay into a baryon and a meson final state. We identify the most promising \bar{10} multiplet for the classification of the Theta^+ and Xi^{--} particles recently discovered with the prediction of a narrow width for both of them. |
1104.2115 | Bennie F. L. Ward | B.F.L. Ward (1,2) ((1) Department of Physics, Baylor University, Waco,
TX, USA, (2) PH-TH, CERN, Geneva, Switzerland) | QCD for the LHC | 15 pages, 5 figures. Invited talk presented at 2011 Epiphany
Conference, Krakow, Poland, Jan., 2011; improved references; added Baylor
preprint number | Acta Phys. Pol.B42:1663-1678, 2011 | 10.5506/APhysPolB.42.1663 | CERN-PH-TH/2011-077; BU-HEPP-11-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the new era of precision QCD as it relates to the physics
requirements of the LHC for both the signal and background type processes. Some
attention is paid to the issue of the theoretical error associated with any
given theoretical prediction. In the cases considered, we present where the
theory precision is at this writing and where it needs to go in order that it
not impede the discovery potential of the LHC physics program. To complete the
discussion, we also discuss possible paradigms the latter program may help us
understand and some new developments that may play a role in achieving that
respective understanding.
| [
{
"created": "Tue, 12 Apr 2011 05:54:55 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Apr 2011 15:21:56 GMT",
"version": "v2"
},
{
"created": "Mon, 2 May 2011 06:35:52 GMT",
"version": "v3"
}
] | 2014-09-05 | [
[
"Ward",
"B. F. L.",
""
]
] | We discuss the new era of precision QCD as it relates to the physics requirements of the LHC for both the signal and background type processes. Some attention is paid to the issue of the theoretical error associated with any given theoretical prediction. In the cases considered, we present where the theory precision is at this writing and where it needs to go in order that it not impede the discovery potential of the LHC physics program. To complete the discussion, we also discuss possible paradigms the latter program may help us understand and some new developments that may play a role in achieving that respective understanding. |
hep-ph/9907333 | Gerhard Ecker | J. Bijnens, G. Colangelo and G. Ecker | Renormalization of chiral perturbation theory to order p^6 | 43 pages, LaTeX2e, 1 figure | Annals Phys. 280 (2000) 100-139 | 10.1006/aphy.1999.5982 | LU TP 99-14, ZU-TH 18/99, UWThPh-1999-42 | hep-ph | null | The renormalization of chiral perturbation theory is carried out to
next-to-next-to-leading order in the meson sector. We calculate the divergent
part of the generating functional of Green functions of quark currents to
O(p^6) for chiral SU(n), involving one- and two-loop diagrams. The
renormalization group equations for the renormalized low-energy constants of
O(p^6) are derived. We compare our results with previous two-loop calculations
in chiral perturbation theory.
| [
{
"created": "Tue, 13 Jul 1999 12:59:40 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Bijnens",
"J.",
""
],
[
"Colangelo",
"G.",
""
],
[
"Ecker",
"G.",
""
]
] | The renormalization of chiral perturbation theory is carried out to next-to-next-to-leading order in the meson sector. We calculate the divergent part of the generating functional of Green functions of quark currents to O(p^6) for chiral SU(n), involving one- and two-loop diagrams. The renormalization group equations for the renormalized low-energy constants of O(p^6) are derived. We compare our results with previous two-loop calculations in chiral perturbation theory. |
1404.6258 | Jeonghyeon Song | Neil D. Christensen, Tao Han, Zhuoni Qian, Josh Sayre, Jeonghyeon
Song, and Stefanus | Determining the Dark Matter Particle Mass through Antler Topology
Processes at Lepton Colliders | Detector simulations implemented; results updated | Phys. Rev. D 90, 114029 (2014) | 10.1103/PhysRevD.90.114029 | PITT-PACC 1402 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the kinematic cusps and endpoints of processes with the "antler
topology" as a way to measure the masses of the parity-odd missing particle and
the intermediate parent at a high energy lepton collider. The fixed center of
mass energy at a lepton collider makes many new physics processes suitable for
the study of the antler decay topology. It also provides new kinematic
observables with cusp structures, optimal for the missing mass determination.
We also study realistic effects on these observables, including initial state
radiation, beamstrahlung, acceptance cuts, and detector resolution. We find
that the new observables, such as the reconstructed invariant mass of invisible
particles and the summed energy of the observable final state particles, appear
to be more stable than the commonly considered energy endpoints against
realistic factors and are very efficient at measuring the missing particle
mass. For the sake of illustration, we study smuon pair production and chargino
pair production within the framework of the minimal supersymmetric standard
model. We adopt the log-likelihood method to optimize the analysis. We find
that at the 500 GeV ILC, a precision of approximately 0.5 GeV can be achieved
in the case of smuon production with a leptonic final state, and approximately
2 GeV in the case of chargino production with a hadronic final state.
| [
{
"created": "Thu, 24 Apr 2014 20:01:26 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Oct 2014 04:31:20 GMT",
"version": "v2"
}
] | 2014-12-31 | [
[
"Christensen",
"Neil D.",
""
],
[
"Han",
"Tao",
""
],
[
"Qian",
"Zhuoni",
""
],
[
"Sayre",
"Josh",
""
],
[
"Song",
"Jeonghyeon",
""
],
[
"Stefanus",
"",
""
]
] | We study the kinematic cusps and endpoints of processes with the "antler topology" as a way to measure the masses of the parity-odd missing particle and the intermediate parent at a high energy lepton collider. The fixed center of mass energy at a lepton collider makes many new physics processes suitable for the study of the antler decay topology. It also provides new kinematic observables with cusp structures, optimal for the missing mass determination. We also study realistic effects on these observables, including initial state radiation, beamstrahlung, acceptance cuts, and detector resolution. We find that the new observables, such as the reconstructed invariant mass of invisible particles and the summed energy of the observable final state particles, appear to be more stable than the commonly considered energy endpoints against realistic factors and are very efficient at measuring the missing particle mass. For the sake of illustration, we study smuon pair production and chargino pair production within the framework of the minimal supersymmetric standard model. We adopt the log-likelihood method to optimize the analysis. We find that at the 500 GeV ILC, a precision of approximately 0.5 GeV can be achieved in the case of smuon production with a leptonic final state, and approximately 2 GeV in the case of chargino production with a hadronic final state. |
1802.09903 | Toshifumi Yamada | Naoyuki Haba, Hiroyuki Umeeda and Toshifumi Yamada | $\epsilon'/\epsilon$ Anomaly and Neutron EDM in $SU(2)_L\times
SU(2)_R\times U(1)_{B-L}$ model with Charge Symmetry | 35 pages, 6 figures. Version accepted for publication in JHEP | null | 10.1007/JHEP05(2018)052 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model prediction for $\epsilon'/\epsilon$ based on recent
lattice QCD results exhibits a tension with the experimental data. We solve
this tension through $W_R^+$ gauge boson exchange in the $SU(2)_L\times
SU(2)_R\times U(1)_{B-L}$ model with `charge symmetry', whose theoretical
motivation is to attribute the chiral structure of the Standard Model to the
spontaneous breaking of $SU(2)_R\times U(1)_{B-L}$ gauge group and charge
symmetry. We show that $M_{W_R}<58$ TeV is required to account for the
$\epsilon'/\epsilon$ anomaly in this model. Next, we make a prediction for the
neutron EDM in the same model and study a correlation between
$\epsilon'/\epsilon$ and the neutron EDM. We confirm that the model can solve
the $\epsilon'/\epsilon$ anomaly without conflicting the current bound on the
neutron EDM, and further reveal that almost all parameter regions in which the
$\epsilon'/\epsilon$ anomaly is explained will be covered by future neutron EDM
searches, which leads us to anticipate the discovery of the neutron EDM.
| [
{
"created": "Tue, 27 Feb 2018 14:29:09 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Mar 2018 17:31:18 GMT",
"version": "v2"
},
{
"created": "Wed, 25 Apr 2018 05:09:26 GMT",
"version": "v3"
}
] | 2018-06-13 | [
[
"Haba",
"Naoyuki",
""
],
[
"Umeeda",
"Hiroyuki",
""
],
[
"Yamada",
"Toshifumi",
""
]
] | The Standard Model prediction for $\epsilon'/\epsilon$ based on recent lattice QCD results exhibits a tension with the experimental data. We solve this tension through $W_R^+$ gauge boson exchange in the $SU(2)_L\times SU(2)_R\times U(1)_{B-L}$ model with `charge symmetry', whose theoretical motivation is to attribute the chiral structure of the Standard Model to the spontaneous breaking of $SU(2)_R\times U(1)_{B-L}$ gauge group and charge symmetry. We show that $M_{W_R}<58$ TeV is required to account for the $\epsilon'/\epsilon$ anomaly in this model. Next, we make a prediction for the neutron EDM in the same model and study a correlation between $\epsilon'/\epsilon$ and the neutron EDM. We confirm that the model can solve the $\epsilon'/\epsilon$ anomaly without conflicting the current bound on the neutron EDM, and further reveal that almost all parameter regions in which the $\epsilon'/\epsilon$ anomaly is explained will be covered by future neutron EDM searches, which leads us to anticipate the discovery of the neutron EDM. |
1608.05279 | Hendrik van Hees | R. Rapp and H. van Hees | Thermal Electromagnetic Radiation in Heavy-Ion Collisions | 5 pages, 4 figures; contribution to the NICA White Paper (EPJA
topical issue) | Eur. Phys. Jour. A 52, 257 (2016) | 10.1140/epja/i2016-16257-0 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the potential of precise measurements of electromagnetic probes in
relativistic heavy-ion collisions for the theoretical understanding of strongly
interacting matter. The penetrating nature of photons and dileptons implies
that they can carry undistorted information about the hot and dense regions of
the fireballs formed in these reactions and thus provide a unique opportunity
to measure the electromagnetic spectral function of QCD matter as a function of
both invariant mass and momentum. In particular we report on recent progress on
how the medium modifications of the (dominant) isovector part of the vector
current correlator ($\rho$ channel) can shed light on the mechanism of chiral
symmetry restoration in the hot and/or dense environment. In addition, thermal
dilepton radiation enables novel access to (a) the fireball lifetime through
the dilepton yield in the low invariant-mass window $0.3 \; \mathrm{GeV} \leq M
\leq 0.7 \; \mathrm{GeV}$, and (b) the early temperatures of the fireball
through the slope of the invariant-mass spectrum in the intermediate-mass
region ($1.5 \; \mathrm{GeV} <M< 2.5 \; \mathrm{GeV}$). The investigation of
the pertinent excitation function suggests that the beam energies provided by
the NICA and FAIR projects are in a promising range for a potential discovery
of the onset of a first order phase transition, as signaled by a non-monotonous
behavior of both low-mass yields and temperature slopes.
| [
{
"created": "Thu, 18 Aug 2016 14:36:43 GMT",
"version": "v1"
}
] | 2016-08-23 | [
[
"Rapp",
"R.",
""
],
[
"van Hees",
"H.",
""
]
] | We review the potential of precise measurements of electromagnetic probes in relativistic heavy-ion collisions for the theoretical understanding of strongly interacting matter. The penetrating nature of photons and dileptons implies that they can carry undistorted information about the hot and dense regions of the fireballs formed in these reactions and thus provide a unique opportunity to measure the electromagnetic spectral function of QCD matter as a function of both invariant mass and momentum. In particular we report on recent progress on how the medium modifications of the (dominant) isovector part of the vector current correlator ($\rho$ channel) can shed light on the mechanism of chiral symmetry restoration in the hot and/or dense environment. In addition, thermal dilepton radiation enables novel access to (a) the fireball lifetime through the dilepton yield in the low invariant-mass window $0.3 \; \mathrm{GeV} \leq M \leq 0.7 \; \mathrm{GeV}$, and (b) the early temperatures of the fireball through the slope of the invariant-mass spectrum in the intermediate-mass region ($1.5 \; \mathrm{GeV} <M< 2.5 \; \mathrm{GeV}$). The investigation of the pertinent excitation function suggests that the beam energies provided by the NICA and FAIR projects are in a promising range for a potential discovery of the onset of a first order phase transition, as signaled by a non-monotonous behavior of both low-mass yields and temperature slopes. |
hep-ph/0408101 | Cristian Pisano | Cristian Pisano | Testing the Equivalent Photon Approximation of the Proton in the Process
$e p\to \nu W X$ | Revised version, one reference added, to appear in EPJ | Eur.Phys.J. C38 (2004) 79-84 | 10.1140/epjc/s2004-02017-x | DO-TH 04/09 | hep-ph | null | The accuracy of the equivalent photon approximation (EPA) of the proton in
describing the inelastic process $ep\to \nu W X$ is investigated. In
particular, the scale dependence of the corresponding inelastic photon
distribution is discussed. Furthermore, an estimate of the total number of
events, including the ones coming from the elastic and quasi-elastic channels
of the reaction, is given for the HERA collider.
| [
{
"created": "Sat, 7 Aug 2004 12:16:11 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Sep 2004 14:32:51 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Pisano",
"Cristian",
""
]
] | The accuracy of the equivalent photon approximation (EPA) of the proton in describing the inelastic process $ep\to \nu W X$ is investigated. In particular, the scale dependence of the corresponding inelastic photon distribution is discussed. Furthermore, an estimate of the total number of events, including the ones coming from the elastic and quasi-elastic channels of the reaction, is given for the HERA collider. |
hep-ph/0402017 | Alberto Casas | J.A. Casas, J.R. Espinosa and I. Hidalgo | A Relief to the Supersymmetric Fine Tuning Problem | Latex file, 10 pages, 3 figures, uses ws-p8-50x6-00.cls; based on
talk given at the String Phenomenology Workshop held at Durham, July 29 -
August 4, 2003 | null | 10.1142/9789812702463_0011 | IFT-UAM/CSIC-04-03 | hep-ph | null | As is well known, electroweak breaking in the MSSM requires substantial
fine-tuning. We explain why this fine tuning problem is abnormally acute, and
this allows to envisage possible solutions to this undesirable situation.
Following these ideas, we review some recent work which shows how in models
with SUSY broken at a low scale (not far from the TeV) this fine-tuning can be
dramatically reduced or even absent.
| [
{
"created": "Mon, 2 Feb 2004 13:37:39 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Casas",
"J. A.",
""
],
[
"Espinosa",
"J. R.",
""
],
[
"Hidalgo",
"I.",
""
]
] | As is well known, electroweak breaking in the MSSM requires substantial fine-tuning. We explain why this fine tuning problem is abnormally acute, and this allows to envisage possible solutions to this undesirable situation. Following these ideas, we review some recent work which shows how in models with SUSY broken at a low scale (not far from the TeV) this fine-tuning can be dramatically reduced or even absent. |
1302.0004 | Ben Heidenreich | Csaba Cs\'aki and Ben Heidenreich | A Complete Model for R-parity Violation | 31 pages, 4 figures | null | 10.1103/PhysRevD.88.055023 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a complete model whose low energy effective theory is the R-parity
violating NMSSM with a baryon number violating udd vertex of the MFV SUSY form,
leading to prompt LSP decay and evading the ever stronger LHC bounds on
low-scale R-parity conserving supersymmetry. MFV flavor structure is enforced
by gauging an SU(3) flavor symmetry at high energies. After the flavor group is
spontaneously broken, mass mixing between the standard model fields and heavy
vector-like quarks and leptons induces hierarchical Yukawa couplings which
depend on the mixing angles. The same mechanism generates the udd coupling,
explaining its shared structure. A discrete R-symmetry is imposed which forbids
all other dangerous lepton and baryon-number violating operators (including
Planck-suppressed operators) and simultaneously solves the mu problem. While
flavor constraints require the flavor gauge bosons to be outside of the reach
of the LHC, the vector-like top partners could lie below 1 TeV.
| [
{
"created": "Thu, 31 Jan 2013 21:00:01 GMT",
"version": "v1"
}
] | 2013-10-02 | [
[
"Csáki",
"Csaba",
""
],
[
"Heidenreich",
"Ben",
""
]
] | We present a complete model whose low energy effective theory is the R-parity violating NMSSM with a baryon number violating udd vertex of the MFV SUSY form, leading to prompt LSP decay and evading the ever stronger LHC bounds on low-scale R-parity conserving supersymmetry. MFV flavor structure is enforced by gauging an SU(3) flavor symmetry at high energies. After the flavor group is spontaneously broken, mass mixing between the standard model fields and heavy vector-like quarks and leptons induces hierarchical Yukawa couplings which depend on the mixing angles. The same mechanism generates the udd coupling, explaining its shared structure. A discrete R-symmetry is imposed which forbids all other dangerous lepton and baryon-number violating operators (including Planck-suppressed operators) and simultaneously solves the mu problem. While flavor constraints require the flavor gauge bosons to be outside of the reach of the LHC, the vector-like top partners could lie below 1 TeV. |
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