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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1804.04135 | Pouya Asadi | Pouya Asadi, Matthew R. Buckley, David Shih | It's all right(-handed neutrinos): a new $W'$ model for the
$R_{D^{(*)}}$ anomaly | 24 pages + appendix, 5 figures. v2: typos fixed, references added,
minor updates, conclusions unchanged | null | 10.1007/JHEP09(2018)010 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The measured $B$-meson semi-leptonic branching ratios $R_{D}$ and $R_{D^*}$
have long-standing deviations between theory and experiment. We introduce a
model which explains both anomalies through a single interaction by introducing
a right-handed neutrino as the missing energy particle. This interaction is
mediated by a heavy charged vector boson ($W'$) which couples only to
right-handed quarks and leptons of the Standard Model through the mixing of
these particles with new vector-like fermions. Previous $W'$ models for the
$R_{D^{(*)}}$ anomaly were strongly constrained from flavor changing neutral
currents and direct collider searches for $Z'\to\tau\tau$ resonances. We show
that relying on right-handed fermion mixing enables us to avoid these
constraints, as well as other severe bounds from electroweak precision tests
and neutrino mixing.
| [
{
"created": "Wed, 11 Apr 2018 18:00:02 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Jan 2019 14:36:56 GMT",
"version": "v2"
}
] | 2019-01-09 | [
[
"Asadi",
"Pouya",
""
],
[
"Buckley",
"Matthew R.",
""
],
[
"Shih",
"David",
""
]
] | The measured $B$-meson semi-leptonic branching ratios $R_{D}$ and $R_{D^*}$ have long-standing deviations between theory and experiment. We introduce a model which explains both anomalies through a single interaction by introducing a right-handed neutrino as the missing energy particle. This interaction is mediated by a heavy charged vector boson ($W'$) which couples only to right-handed quarks and leptons of the Standard Model through the mixing of these particles with new vector-like fermions. Previous $W'$ models for the $R_{D^{(*)}}$ anomaly were strongly constrained from flavor changing neutral currents and direct collider searches for $Z'\to\tau\tau$ resonances. We show that relying on right-handed fermion mixing enables us to avoid these constraints, as well as other severe bounds from electroweak precision tests and neutrino mixing. |
2004.10942 | Geng Li | Geng Li, Tianhong Wang, Yue Jiang, Jing-Bo Zhang and Guo-Li Wang | Spin-$1/2$ invisible particles in heavy meson decays | 21 pages, 35 figures | Phys. Rev. D 102, 095019 (2020) | 10.1103/PhysRevD.102.095019 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The flavor-changing neutral current decay processes of the $B$ and $B_c$
mesons with the final states involving spin-$1/2$ particles are investigated.
By considering the background of the Standard Model where $\nu\bar\nu$
contributes the missing energy and the experimental upper bounds for the
branching fractions, we get the constraints of the coupling constants of the
quark-antiquark and the assumed invisible particles $\chi\bar\chi$. The
constraints of the coupling constants are then used to study the similar
processes of the $B_c$ meson. At some specific region of $m_\chi$, the upper
limit of BR($B_c\to D_{(s)}\chi\bar\chi$) is of the order of $10^{-6}$, while
for BR($B_c\to D^\ast_{(s)}\chi\bar\chi$), it is $10^{-5}$. The possibility of
distinguishing $\chi$ to be a Majorana or Dirac fermion by the differential
branching fractions is also discussed.
| [
{
"created": "Thu, 23 Apr 2020 02:46:55 GMT",
"version": "v1"
},
{
"created": "Sun, 26 Jul 2020 03:44:19 GMT",
"version": "v2"
},
{
"created": "Thu, 19 Nov 2020 12:41:35 GMT",
"version": "v3"
}
] | 2020-11-20 | [
[
"Li",
"Geng",
""
],
[
"Wang",
"Tianhong",
""
],
[
"Jiang",
"Yue",
""
],
[
"Zhang",
"Jing-Bo",
""
],
[
"Wang",
"Guo-Li",
""
]
] | The flavor-changing neutral current decay processes of the $B$ and $B_c$ mesons with the final states involving spin-$1/2$ particles are investigated. By considering the background of the Standard Model where $\nu\bar\nu$ contributes the missing energy and the experimental upper bounds for the branching fractions, we get the constraints of the coupling constants of the quark-antiquark and the assumed invisible particles $\chi\bar\chi$. The constraints of the coupling constants are then used to study the similar processes of the $B_c$ meson. At some specific region of $m_\chi$, the upper limit of BR($B_c\to D_{(s)}\chi\bar\chi$) is of the order of $10^{-6}$, while for BR($B_c\to D^\ast_{(s)}\chi\bar\chi$), it is $10^{-5}$. The possibility of distinguishing $\chi$ to be a Majorana or Dirac fermion by the differential branching fractions is also discussed. |
0705.0294 | Stuart Raby | Stuart Raby and Akin Wingerter | Gauge coupling unification and light Exotica in String Theory | 5 pages, no figures | Phys.Rev.Lett.99:051802,2007 | 10.1103/PhysRevLett.99.051802 | OHSTPY-HEP-T-07-001 | hep-ph | null | In this letter we consider the consequences for the LHC of light vector-like
exotica with fractional electric charge. It is shown that such states are found
in orbifold constructions of the heterotic string. Moreover, these exotica are
consistent with gauge coupling unification at one loop, even though they do not
come in complete multiplets of SU(5).
| [
{
"created": "Wed, 2 May 2007 14:12:05 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Raby",
"Stuart",
""
],
[
"Wingerter",
"Akin",
""
]
] | In this letter we consider the consequences for the LHC of light vector-like exotica with fractional electric charge. It is shown that such states are found in orbifold constructions of the heterotic string. Moreover, these exotica are consistent with gauge coupling unification at one loop, even though they do not come in complete multiplets of SU(5). |
hep-ph/9808375 | Stefan Kretzer | S. Kretzer and I. Schienbein (Univ. Dortmund) | Heavy Quark Fragmentation in Deep Inelastic Scattering | 24 pages, LaTeX, 4 figures, uses epsfig and amssymb style, corrected
references | Phys.Rev. D59 (1999) 054004 | 10.1103/PhysRevD.59.054004 | DO-TH 98/14 | hep-ph | null | We perform an analysis of semi-inclusive production of charm (D-mesons) in
neutral current (NC) and charged current (CC) deep inelastic scattering (DIS)
at full O(alpha_s^1). Our calculation is based on the heavy quark scheme
developed by Aivazis, Collins, Olness and Tung (ACOT) where we include an
O(alpha_s^1) calculation of quark scattering contributions for general masses
and couplings. We review the relevant massive formulae and subtraction terms
and discuss their massless limits. We show how the charm fragmentation function
can be measured in CC DIS and we investigate whether the charm production
dynamics may be tested in NC DIS. We also discuss finite initial state quark
mass effects in CC and NC DIS.
| [
{
"created": "Thu, 20 Aug 1998 17:40:04 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Aug 1998 18:32:02 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kretzer",
"S.",
"",
"Univ. Dortmund"
],
[
"Schienbein",
"I.",
"",
"Univ. Dortmund"
]
] | We perform an analysis of semi-inclusive production of charm (D-mesons) in neutral current (NC) and charged current (CC) deep inelastic scattering (DIS) at full O(alpha_s^1). Our calculation is based on the heavy quark scheme developed by Aivazis, Collins, Olness and Tung (ACOT) where we include an O(alpha_s^1) calculation of quark scattering contributions for general masses and couplings. We review the relevant massive formulae and subtraction terms and discuss their massless limits. We show how the charm fragmentation function can be measured in CC DIS and we investigate whether the charm production dynamics may be tested in NC DIS. We also discuss finite initial state quark mass effects in CC and NC DIS. |
0804.4004 | Martin Beneke | M. Beneke (RWTH Aachen U.), Y. Kiyo (Karlsruhe U.) | Ultrasoft contribution to heavy-quark pair production near threshold | 10 pages, LaTeX | Phys.Lett.B668:143-147,2008 | 10.1016/j.physletb.2008.08.031 | PITHA~08/07, TTP/08-11, SFB/CPP-08-18 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the third-order correction to the heavy-quark current correlation
function due to the emission and absorption of an ultrasoft gluon. Our result
supplies a missing contribution to top-quark pair production near threshold and
the determination of the bottom quark mass from QCD sum rules.
| [
{
"created": "Thu, 24 Apr 2008 20:03:28 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Beneke",
"M.",
"",
"RWTH Aachen U."
],
[
"Kiyo",
"Y.",
"",
"Karlsruhe U."
]
] | We compute the third-order correction to the heavy-quark current correlation function due to the emission and absorption of an ultrasoft gluon. Our result supplies a missing contribution to top-quark pair production near threshold and the determination of the bottom quark mass from QCD sum rules. |
1511.09242 | Namit Mahajan | Namit Mahajan | Light neutrino contribution: is it all there is to neutrinoless double
beta decay? | 5 pages, 1 figure. arXiv admin note: text overlap with
arXiv:1406.2606 | null | null | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider perturbative one loop QCD corrections to the light neutrino
contribution to neutrinoless double beta decay and find large enhancement to
the rate. QCD corrections also generate structures which mimic new physics
contributions usually considered. Within some approximations, the net effect
seem to almost saturate the experimental limits, and therefore seems to implt
that this is all there is to neutrinoless double beta decay.
| [
{
"created": "Mon, 30 Nov 2015 11:19:19 GMT",
"version": "v1"
}
] | 2015-12-01 | [
[
"Mahajan",
"Namit",
""
]
] | We consider perturbative one loop QCD corrections to the light neutrino contribution to neutrinoless double beta decay and find large enhancement to the rate. QCD corrections also generate structures which mimic new physics contributions usually considered. Within some approximations, the net effect seem to almost saturate the experimental limits, and therefore seems to implt that this is all there is to neutrinoless double beta decay. |
hep-ph/9908496 | Jose Antonio Oller | E. Oset, A. Hosaka, J.C. Nacher, M. Oka, J.A. Oller, A. Parreno, J.R.
Pelaez, A. Ramos, H. Toki | SU(3) Chiral approach to meson and baryon dynamics | 4 pages,3 figures, LaTeX, Talk given at PANIC99, Uppsala (Sweden),
June 10-16, 1999 | Nucl.Phys. A663 (2000) 497-500 | 10.1016/S0375-9474(99)00640-5 | null | hep-ph | null | We report on recent progress on the chiral unitary approach, which is shown
to have a much larger convergence radius than ordinary chiral perturbation
theory, allowing one to reproduce data for meson meson interaction up to 1.2
GeV and meson baryon interaction up to the first baryonic resonances.
Applications to physical processes so far unsuited for a standard chiral
perturbative approach are presented, concretely the K^- p\to\Lambda(1405)\gamma
reaction and the N^\ast (1535)N^\ast(1535)\pi and \eta couplings.
| [
{
"created": "Sat, 28 Aug 1999 08:41:08 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Oset",
"E.",
""
],
[
"Hosaka",
"A.",
""
],
[
"Nacher",
"J. C.",
""
],
[
"Oka",
"M.",
""
],
[
"Oller",
"J. A.",
""
],
[
"Parreno",
"A.",
""
],
[
"Pelaez",
"J. R.",
""
],
[
"Ramos",
"A.",
""
],
[
"Toki",
"H.",
""
]
] | We report on recent progress on the chiral unitary approach, which is shown to have a much larger convergence radius than ordinary chiral perturbation theory, allowing one to reproduce data for meson meson interaction up to 1.2 GeV and meson baryon interaction up to the first baryonic resonances. Applications to physical processes so far unsuited for a standard chiral perturbative approach are presented, concretely the K^- p\to\Lambda(1405)\gamma reaction and the N^\ast (1535)N^\ast(1535)\pi and \eta couplings. |
hep-ph/9307286 | Masoud Mohazzab | Masoud Mohazzab (Brown) | Cusp Annihilation on Ordinary Cosmic Strings | 8 pages, uses phyzzx, BROWN-HET-912 | Int. J. Mod. Phys. D3 (1994) 493-498 | 10.1142/S0218271894000654 | null | hep-ph astro-ph | null | The order of magnitude of energy emission from cusps to light bosons on
ordinary cosmic strings is calculated perturbatively. The analysis is
applicable to both closed string loops and long cosmic strings. The
perturbative result obtained here is much less than what is found by
non-perturbative approximations.
| [
{
"created": "Fri, 16 Jul 1993 16:03:04 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Mohazzab",
"Masoud",
"",
"Brown"
]
] | The order of magnitude of energy emission from cusps to light bosons on ordinary cosmic strings is calculated perturbatively. The analysis is applicable to both closed string loops and long cosmic strings. The perturbative result obtained here is much less than what is found by non-perturbative approximations. |
1810.02138 | Chao-Yi L\"u | Chao-Yi L\"u, Ping Wang, Yu-Bing Dong, Peng-Nian Shen, Zong-Ye Zhang | The opportunity to find $\bar{d}^\ast(2380)$ in the $\Upsilon(nS)$ decay | 7 pages, 3 figures, 1 table | Phys. Rev. D 99, 036015 (2019) | 10.1103/PhysRevD.99.036015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | $d^\ast(2380)$ was observed by WASA-at-COSY collaborations in the nuclear
reaction recently. Its particularly narrow width may indicate the new
QCD-allowed hadronic structure. To further confirm the existence of this
peculiar particle in a totally different kind of reaction, we study the
opportunity for searching $\bar{d}^\ast$ in the $\Upsilon(nS)$ (with n=1, 2, 3)
decay. As a phenomenological study, our framework is based on SU(3) chiral
quark model. By virtue of the unitarity of $S$-matrix and crossing symmetry, we
study the imaginary part of the forward scattering amplitudes between
$\Upsilon(nS)$ and $d^\ast$. The scattering process is mainly governed by the
quark-meson interaction. We examine both the pseudoscalar and vector meson
contribution in the intermediate state. Hopefully, our results show that it's
quite possible to find $\bar{d}^\ast$ in this decay mode in the future.
| [
{
"created": "Thu, 4 Oct 2018 10:28:55 GMT",
"version": "v1"
}
] | 2019-02-27 | [
[
"Lü",
"Chao-Yi",
""
],
[
"Wang",
"Ping",
""
],
[
"Dong",
"Yu-Bing",
""
],
[
"Shen",
"Peng-Nian",
""
],
[
"Zhang",
"Zong-Ye",
""
]
] | $d^\ast(2380)$ was observed by WASA-at-COSY collaborations in the nuclear reaction recently. Its particularly narrow width may indicate the new QCD-allowed hadronic structure. To further confirm the existence of this peculiar particle in a totally different kind of reaction, we study the opportunity for searching $\bar{d}^\ast$ in the $\Upsilon(nS)$ (with n=1, 2, 3) decay. As a phenomenological study, our framework is based on SU(3) chiral quark model. By virtue of the unitarity of $S$-matrix and crossing symmetry, we study the imaginary part of the forward scattering amplitudes between $\Upsilon(nS)$ and $d^\ast$. The scattering process is mainly governed by the quark-meson interaction. We examine both the pseudoscalar and vector meson contribution in the intermediate state. Hopefully, our results show that it's quite possible to find $\bar{d}^\ast$ in this decay mode in the future. |
1807.00894 | Javier Llorente | Javier Llorente and Benjamin Nachman | Limits on new coloured fermions using precision jet data from the Large
Hadron Collider | 16 pages, 8 figures. v3 matches the published version | Nuclear Physics B 936 (2018) 106-117 | 10.1016/j.nuclphysb.2018.09.008 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This work presents an interpretation of high precision jet data from the
ATLAS experiment in terms of exclusion limits for new coloured matter. To this
end, the effect of a new coloured fermion with a mass $m_X$ on the solution of
the renormalization group equation QCD is studied. Theoretical predictions for
the transverse energy-energy correlation function and its asymmetry are
obtained with such a modified solution and, from the comparison to data, 95\%
CL exclusion limits are set on such models.
| [
{
"created": "Mon, 2 Jul 2018 21:19:43 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Jul 2018 18:13:42 GMT",
"version": "v2"
},
{
"created": "Thu, 27 Sep 2018 15:27:26 GMT",
"version": "v3"
}
] | 2018-09-28 | [
[
"Llorente",
"Javier",
""
],
[
"Nachman",
"Benjamin",
""
]
] | This work presents an interpretation of high precision jet data from the ATLAS experiment in terms of exclusion limits for new coloured matter. To this end, the effect of a new coloured fermion with a mass $m_X$ on the solution of the renormalization group equation QCD is studied. Theoretical predictions for the transverse energy-energy correlation function and its asymmetry are obtained with such a modified solution and, from the comparison to data, 95\% CL exclusion limits are set on such models. |
1404.4977 | Christopher McCabe | Celine Boehm, Matthew J. Dolan and Christopher McCabe | A weighty interpretation of the Galactic Centre excess | 5 pages, 4 figures. v2: Matches PRD version. Note: title of PRD
version is "Interpretation of the Galactic Center excess of gamma rays with
heavier dark matter particles" | Phys. Rev. D 90, 023531 (2014) | 10.1103/PhysRevD.90.023531 | IPPP/14/33 DCPT/14/64, SLAC-PUB-15945 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Previous attempts at explaining the gamma-ray excess near the Galactic Centre
have focussed on dark matter annihilation directly into Standard Model
particles. This results in a preferred dark matter mass of 30-40 GeV (if the
annihilation is into b quarks) or 10 GeV (if it is into leptons). Here we show
that the gamma-ray excess is also consistent with heavier dark matter
particles; in models of secluded dark matter, dark matter with mass up to 76
GeV provides a good fit to the data. This occurs if the dark matter first
annihilates to an on-shell particle that subsequently decays to Standard Model
particles through a portal interaction. This is a generic process that works in
models with annihilation, semi-annihilation or both. We explicitly demonstrate
this in a model of hidden vector dark matter with an SU(2) gauge group in the
hidden sector.
| [
{
"created": "Sat, 19 Apr 2014 17:56:31 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Jul 2014 08:57:49 GMT",
"version": "v2"
}
] | 2014-07-30 | [
[
"Boehm",
"Celine",
""
],
[
"Dolan",
"Matthew J.",
""
],
[
"McCabe",
"Christopher",
""
]
] | Previous attempts at explaining the gamma-ray excess near the Galactic Centre have focussed on dark matter annihilation directly into Standard Model particles. This results in a preferred dark matter mass of 30-40 GeV (if the annihilation is into b quarks) or 10 GeV (if it is into leptons). Here we show that the gamma-ray excess is also consistent with heavier dark matter particles; in models of secluded dark matter, dark matter with mass up to 76 GeV provides a good fit to the data. This occurs if the dark matter first annihilates to an on-shell particle that subsequently decays to Standard Model particles through a portal interaction. This is a generic process that works in models with annihilation, semi-annihilation or both. We explicitly demonstrate this in a model of hidden vector dark matter with an SU(2) gauge group in the hidden sector. |
hep-ph/0512308 | Szabolcs Borsanyi | Szabolcs Borsanyi | Nonequilibrium field theory from the 2PI effective action | Invited talk given at the 29th Johns Hopkins Workshop on current
problems in particle theory: Strong matter in the heavens | null | null | null | hep-ph | null | Nonperturbative approximation schemes are inevitable even in weakly coupled
theories if the nonequilibrium behavior of quantum fields is investigated. The
two-particle irreducible (2PI) effective action formalism provides an efficient
framework for obtaining resummation schemes both in and out of equilibrium. We
briefly review the these techniques and discuss recent findings for
nonequilibrium field theories.
| [
{
"created": "Thu, 22 Dec 2005 20:00:24 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Borsanyi",
"Szabolcs",
""
]
] | Nonperturbative approximation schemes are inevitable even in weakly coupled theories if the nonequilibrium behavior of quantum fields is investigated. The two-particle irreducible (2PI) effective action formalism provides an efficient framework for obtaining resummation schemes both in and out of equilibrium. We briefly review the these techniques and discuss recent findings for nonequilibrium field theories. |
hep-ph/0412216 | Egle Tomasi-Gustafsson | E. Tomasi-Gustafsson | On the intrinsic limitation of the Rosenbluth method at large momentum
transfer | 10 pages, 4 figures | null | null | null | hep-ph | null | Correlations in the elastic electron proton scattering data show that the
Rosenbluth method is not reliable for the extraction of the electric proton
form factors at large momentum transfer, where the magnetic term dominates, due
to the size and the $\epsilon$ dependence of the radiative corrections.
| [
{
"created": "Wed, 15 Dec 2004 16:58:03 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Tomasi-Gustafsson",
"E.",
""
]
] | Correlations in the elastic electron proton scattering data show that the Rosenbluth method is not reliable for the extraction of the electric proton form factors at large momentum transfer, where the magnetic term dominates, due to the size and the $\epsilon$ dependence of the radiative corrections. |
1605.02407 | Qiang Zhao | Wen Qin, Si-Run Xue, Qiang Zhao | Production of $Y(4260)$ as a hadronic molecule state of $\bar{D}D_1
+c.c.$ in $e^+e^-$ annihilations | Revised version to appear in Phys. Rev. D | Phys. Rev. D 94, 054035 (2016) | 10.1103/PhysRevD.94.054035 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $Y(4260)$ production mechanism in $e^+e^-$ annihilations in the
framework of hadronic molecules and investigate the consequence of such a
picture in different decay channels. In the hadronic molecule picture the
$Y(4260)$ is described as a mixture state composed of a long-ranged
$\bar{D}D_1(2420)+c.c.$ molecule state and a compact $c\bar{c}$ component. We
show that the compositeness relation can still provide a reasonable constraint
on the wavefunction renormalization parameter due to the dominance of the
molecular component. Such a mechanism can be regarded as a natural consequence
of the heavy quark spin symmetry (HQSS) breaking. This study elaborates the
molecular picture for the $Y(4260)$ in the $e^+e^-$ annihilations and affirms
that the cross section lineshape of $e^+e^-\to \bar{D}D^*\pi+c.c.$ in the
vicinity of the $Y(4260)$ should have a nontrivial behavior. In this framework
we predict that the upper limit of the $Y(4260)$ leptonic decay width is about
500 eV. We also investigate the coupling for $D_1(2420)\to D^*\pi$ in the
$^3P_0$ quark model and examine the possible HQSS breaking effects due to the
deviation from the $|^1P_1\rangle$ and $|^3P_1\rangle$ ideal mixing. This will
in turn provide a constraint on the HQSS breaking coupling for the $Y(4260)$ to
$\bar{D}D_1(2420)+c.c.$ via its $c\bar{c}$ component.
| [
{
"created": "Mon, 9 May 2016 03:31:42 GMT",
"version": "v1"
},
{
"created": "Sat, 10 Sep 2016 03:30:57 GMT",
"version": "v2"
}
] | 2016-10-05 | [
[
"Qin",
"Wen",
""
],
[
"Xue",
"Si-Run",
""
],
[
"Zhao",
"Qiang",
""
]
] | We study the $Y(4260)$ production mechanism in $e^+e^-$ annihilations in the framework of hadronic molecules and investigate the consequence of such a picture in different decay channels. In the hadronic molecule picture the $Y(4260)$ is described as a mixture state composed of a long-ranged $\bar{D}D_1(2420)+c.c.$ molecule state and a compact $c\bar{c}$ component. We show that the compositeness relation can still provide a reasonable constraint on the wavefunction renormalization parameter due to the dominance of the molecular component. Such a mechanism can be regarded as a natural consequence of the heavy quark spin symmetry (HQSS) breaking. This study elaborates the molecular picture for the $Y(4260)$ in the $e^+e^-$ annihilations and affirms that the cross section lineshape of $e^+e^-\to \bar{D}D^*\pi+c.c.$ in the vicinity of the $Y(4260)$ should have a nontrivial behavior. In this framework we predict that the upper limit of the $Y(4260)$ leptonic decay width is about 500 eV. We also investigate the coupling for $D_1(2420)\to D^*\pi$ in the $^3P_0$ quark model and examine the possible HQSS breaking effects due to the deviation from the $|^1P_1\rangle$ and $|^3P_1\rangle$ ideal mixing. This will in turn provide a constraint on the HQSS breaking coupling for the $Y(4260)$ to $\bar{D}D_1(2420)+c.c.$ via its $c\bar{c}$ component. |
1202.2673 | Takehiro Nabeshima | Takehiro Nabeshima | Higgs portal dark matter at a linear collider | 7 pages, 2 figures. Proceedings of International Linear Collider
Workshop (LCWS11), Sep. 26-30, 2011, Granada, Spain | null | null | UT-HET 066 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the possibility of detecting dark matter at TeV scale linear
colliders in the scenario where the dark matter interacts with standard model
particles only via the Higgs boson. In this scenario, the dark matter would be
difficult to be tested at the LHC especially when the decay of the Higgs boson
into a dark matter pair is not kinematically allowed. In this talk, we discuss
whether even such a case can be explored or not at the ILC and CLIC via the Z
boson fusion process. This talk is mainly based on Phys. Rev. D 82, 055026
(2010) and Phys. Lett. B 701, 591 (2011).
| [
{
"created": "Mon, 13 Feb 2012 09:42:05 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Feb 2012 06:20:19 GMT",
"version": "v2"
}
] | 2012-02-24 | [
[
"Nabeshima",
"Takehiro",
""
]
] | We investigate the possibility of detecting dark matter at TeV scale linear colliders in the scenario where the dark matter interacts with standard model particles only via the Higgs boson. In this scenario, the dark matter would be difficult to be tested at the LHC especially when the decay of the Higgs boson into a dark matter pair is not kinematically allowed. In this talk, we discuss whether even such a case can be explored or not at the ILC and CLIC via the Z boson fusion process. This talk is mainly based on Phys. Rev. D 82, 055026 (2010) and Phys. Lett. B 701, 591 (2011). |
1305.1237 | Jacek Syska Mr. | Jacek Syska | The weak bound state with the non-zero charge density as the LHC 126.5
GeV state | 23 pages, 15 figures, Keywords: self-consistent field theory, physics
beyond the Standard Model | J. Phys. Part. Nuclei (2016) 47: 838-862 | 10.1134/S1063779616050063 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The self-consistent model of classical field interactions formulated as the
counterpart of the quantum electroweak model leads to homogeneous boson ground
state solutions in presence of non-zero extended fermionic charge density
fluctuations. Two different types of electroweak configurations of fields are
analyzed. The first one has non-zero electric and weak charge fluctuations. The
second one is electrically uncharged but weakly charged. Both types of
configurations have two physically interesting solutions which possess masses
equal to 126.67 GeV at the value of the scalar fluctuation potential parameter
$\lambda$ equal to ~ 0.0652. The spin zero electrically uncharged droplet
formed as a result of the decay of the charged one is interpreted as the ~
126.5 GeV state found in the Large Hadron Collider (LHC) experiment. (The other
two configurations correspond to solutions with masses equal to 123.7 GeV and
$\lambda$ equal to ~ 0.0498 and thus the algebraic mean of the masses of two
central solutions, i.e., 126.67 GeV and 123.7 GeV, is equal to 125.185 GeV.)
The problem of a mass of this kind of droplets will be considered on the basis
of the phenomenon of the screening of the fluctuation of charges. Their masses
are found in the thin wall approximation.
| [
{
"created": "Thu, 2 May 2013 15:56:58 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Nov 2014 00:51:04 GMT",
"version": "v2"
},
{
"created": "Sat, 3 Sep 2016 17:03:46 GMT",
"version": "v3"
}
] | 2016-09-06 | [
[
"Syska",
"Jacek",
""
]
] | The self-consistent model of classical field interactions formulated as the counterpart of the quantum electroweak model leads to homogeneous boson ground state solutions in presence of non-zero extended fermionic charge density fluctuations. Two different types of electroweak configurations of fields are analyzed. The first one has non-zero electric and weak charge fluctuations. The second one is electrically uncharged but weakly charged. Both types of configurations have two physically interesting solutions which possess masses equal to 126.67 GeV at the value of the scalar fluctuation potential parameter $\lambda$ equal to ~ 0.0652. The spin zero electrically uncharged droplet formed as a result of the decay of the charged one is interpreted as the ~ 126.5 GeV state found in the Large Hadron Collider (LHC) experiment. (The other two configurations correspond to solutions with masses equal to 123.7 GeV and $\lambda$ equal to ~ 0.0498 and thus the algebraic mean of the masses of two central solutions, i.e., 126.67 GeV and 123.7 GeV, is equal to 125.185 GeV.) The problem of a mass of this kind of droplets will be considered on the basis of the phenomenon of the screening of the fluctuation of charges. Their masses are found in the thin wall approximation. |
hep-ph/9411364 | Lee Chang-Hwan | Chang-Hwan Lee and Mannque Rho | Kaon Condensation in Dense Stellar Matter | 16 pages, epsfig.sty, 1 figure(uuencoded) | null | null | SNUTP-94-121 | hep-ph nucl-th | null | This talk is based on work done in collaboration with G.E. Brown and D.-P.
Min on kaon condensation in dense baryonic medium treated in chiral
perturbation theory using heavy-baryon formalism. It contains, in addition to
what was recently published, some new results based on the analysis on kaonic
atoms by Friedman, Gal and Batty and a discussion on a renormalization-group
analysis to meson condensation made together with H.K. Lee and Sin. Negatively
charged kaons are predicted to condense at the critical density $2\lsim
\rho/\rho_0\lsim 4$, in the range to allow all the intriguing new phenomena
predicted by Brown and Bethe to take place in compact star matter.
| [
{
"created": "Wed, 23 Nov 1994 04:30:48 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lee",
"Chang-Hwan",
""
],
[
"Rho",
"Mannque",
""
]
] | This talk is based on work done in collaboration with G.E. Brown and D.-P. Min on kaon condensation in dense baryonic medium treated in chiral perturbation theory using heavy-baryon formalism. It contains, in addition to what was recently published, some new results based on the analysis on kaonic atoms by Friedman, Gal and Batty and a discussion on a renormalization-group analysis to meson condensation made together with H.K. Lee and Sin. Negatively charged kaons are predicted to condense at the critical density $2\lsim \rho/\rho_0\lsim 4$, in the range to allow all the intriguing new phenomena predicted by Brown and Bethe to take place in compact star matter. |
hep-ph/0111239 | Valentina Sadovnikova | E.G. Drukarev, M.G. Ryskin, V.A. Sadovnikova | Expectation values of four-quark operators in pions | 9 pages, no figures, typos corrected | Phys.Rev.D65:074015,2002; Erratum-ibid.D66:039903,2002 | 10.1103/PhysRevD.65.074015 10.1103/PhysRevD.66.039903 | null | hep-ph | null | The values of four-quark operators averaged over pions are expressed through
those averaged over vacuum. The specific values are obtained in the framework
of the factorization assumption. For the condensates of the light quarks of the
same flavour \bar q\Gamma q\bar q\Gamma q the scalar condensate is shown to be
an order of magnitude larger than the other ones. The condensates containing
the strange quarks \bar q q\bar s s appear to be only about twice smaller than
those of the light quarks. The degeneracy of the ground state in the
Nambu--Jona--Lasinio model is shown explicitly.
| [
{
"created": "Tue, 20 Nov 2001 08:11:53 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Jun 2002 11:40:27 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Drukarev",
"E. G.",
""
],
[
"Ryskin",
"M. G.",
""
],
[
"Sadovnikova",
"V. A.",
""
]
] | The values of four-quark operators averaged over pions are expressed through those averaged over vacuum. The specific values are obtained in the framework of the factorization assumption. For the condensates of the light quarks of the same flavour \bar q\Gamma q\bar q\Gamma q the scalar condensate is shown to be an order of magnitude larger than the other ones. The condensates containing the strange quarks \bar q q\bar s s appear to be only about twice smaller than those of the light quarks. The degeneracy of the ground state in the Nambu--Jona--Lasinio model is shown explicitly. |
hep-ph/9802335 | Hooman Davoudiasl | Hooman Davoudiasl, Eric Westphal (Caltech) | Diffusion and Decoherence of Squarks and Quarks During the Electroweak
Phase Transition | 11 pages. Expanded discussion of our method and approximations,
reference added | Phys.Lett. B432 (1998) 128-133 | 10.1016/S0370-2693(98)00616-9 | CALT-68-2156 | hep-ph | null | To estimate the diffusion constant $D$ of particles in a plasma, we develop a
method that is based on the mean free path $\lambda$ for scatterings with
momentum transfer $q >~ T$. Using this method, we estimate $\lambda$ and $D$
for squarks and quarks during the electroweak phase transition. Assuming that
Debye and magnetic screening lengths provide suitable infrared cutoffs, our
calculations yield $\lambda <~ 18/T$ and $D <~ 5/T$ for both squarks and
quarks. Our estimate of $\lambda$ suggests that suppressions of charge
transport due to decoherence of these strongly interacting particles during the
electroweak phase transition are not severe and that these particles may
contribute significantly to electroweak baryogenesis.
| [
{
"created": "Tue, 17 Feb 1998 20:03:21 GMT",
"version": "v1"
},
{
"created": "Wed, 13 May 1998 21:01:49 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Davoudiasl",
"Hooman",
"",
"Caltech"
],
[
"Westphal",
"Eric",
"",
"Caltech"
]
] | To estimate the diffusion constant $D$ of particles in a plasma, we develop a method that is based on the mean free path $\lambda$ for scatterings with momentum transfer $q >~ T$. Using this method, we estimate $\lambda$ and $D$ for squarks and quarks during the electroweak phase transition. Assuming that Debye and magnetic screening lengths provide suitable infrared cutoffs, our calculations yield $\lambda <~ 18/T$ and $D <~ 5/T$ for both squarks and quarks. Our estimate of $\lambda$ suggests that suppressions of charge transport due to decoherence of these strongly interacting particles during the electroweak phase transition are not severe and that these particles may contribute significantly to electroweak baryogenesis. |
1009.5320 | Kazem Azizi | K. Azizi, H. Sundu | $g_{D^{\ast}_{s}D K^{\ast}(892)}$ and $g_{B^{\ast}_{s}B K^{\ast}(892)}$
coupling constants in QCD sum rules | 13 Pages and 11 Figures | J.Phys.G38:045005,2011 | 10.1088/0954-3899/38/4/045005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The coupling constants $g_{D^{\ast}_{s}D K^{\ast}(892)}$ and
$g_{B^{\ast}_{s}B K^{\ast}(892)}$ are calculated in the framework of
three-point QCD sum rules. The correlation functions responsible for these
coupling constants are evaluated considering contributions of both $D(B)$ and
$K^*(892)$ mesons as off-shell states, but in the absence of radiative
corrections. The results, $g_{D^{\ast}_{s}D K^{\ast}(892)}=(4.31\pm1.42)
GeV^{-1}$ and $g_{B^{\ast}_{s}B K^{\ast}(892)}=(3.24\pm1.08) GeV^{-1}$ are
obtained for the considered strong coupling constants.
| [
{
"created": "Mon, 27 Sep 2010 16:45:37 GMT",
"version": "v1"
},
{
"created": "Sat, 15 Jan 2011 10:40:05 GMT",
"version": "v2"
}
] | 2011-03-03 | [
[
"Azizi",
"K.",
""
],
[
"Sundu",
"H.",
""
]
] | The coupling constants $g_{D^{\ast}_{s}D K^{\ast}(892)}$ and $g_{B^{\ast}_{s}B K^{\ast}(892)}$ are calculated in the framework of three-point QCD sum rules. The correlation functions responsible for these coupling constants are evaluated considering contributions of both $D(B)$ and $K^*(892)$ mesons as off-shell states, but in the absence of radiative corrections. The results, $g_{D^{\ast}_{s}D K^{\ast}(892)}=(4.31\pm1.42) GeV^{-1}$ and $g_{B^{\ast}_{s}B K^{\ast}(892)}=(3.24\pm1.08) GeV^{-1}$ are obtained for the considered strong coupling constants. |
1704.00113 | Tianbo Liu | Tianbo Liu, Zhiwen Zhao, Haiyan Gao | Experimental constraint on quark electric dipole moments | 8 pages, 3 figures | Phys. Rev. D 97, 074018 (2018) | 10.1103/PhysRevD.97.074018 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The electric dipole moments (EDMs) of nucleons are sensitive probes of
additional $\cal CP$ violation sources beyond the standard model to account for
the baryon number asymmetry of the universe. As a fundamental quantity of the
nucleon structure, tensor charge is also a bridge that relates nucleon EDMs to
quark EDMs. With a combination of nucleon EDM measurements and tensor charge
extractions, we investigate the experimental constraint on quark EDMs, and its
sensitivity to $\cal CP$ violation sources from new physics beyond the
electroweak scale. We obtain the current limits on quark EDMs as
$1.27\times10^{-24}\,e\cdot{\rm cm}$ for the up quark and
$1.17\times10^{-24}\,e\cdot{\rm cm}$ for the down quark at the scale of $4\,\rm
GeV^2$. We also study the impact of future nucleon EDM and tensor charge
measurements, and show that upcoming new experiments will improve the
constraint on quark EDMs by about three orders of magnitude leading to a much
more sensitive probe of new physics models.
| [
{
"created": "Sat, 1 Apr 2017 03:22:56 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Jan 2018 14:26:37 GMT",
"version": "v2"
}
] | 2018-04-25 | [
[
"Liu",
"Tianbo",
""
],
[
"Zhao",
"Zhiwen",
""
],
[
"Gao",
"Haiyan",
""
]
] | The electric dipole moments (EDMs) of nucleons are sensitive probes of additional $\cal CP$ violation sources beyond the standard model to account for the baryon number asymmetry of the universe. As a fundamental quantity of the nucleon structure, tensor charge is also a bridge that relates nucleon EDMs to quark EDMs. With a combination of nucleon EDM measurements and tensor charge extractions, we investigate the experimental constraint on quark EDMs, and its sensitivity to $\cal CP$ violation sources from new physics beyond the electroweak scale. We obtain the current limits on quark EDMs as $1.27\times10^{-24}\,e\cdot{\rm cm}$ for the up quark and $1.17\times10^{-24}\,e\cdot{\rm cm}$ for the down quark at the scale of $4\,\rm GeV^2$. We also study the impact of future nucleon EDM and tensor charge measurements, and show that upcoming new experiments will improve the constraint on quark EDMs by about three orders of magnitude leading to a much more sensitive probe of new physics models. |
hep-ph/0107136 | null | J. Dias de Deus and Yu.M.Shabelski (CENTRA, Instituto Superior
Tecnico, Lisbon, Portugal) | Cross Sections, Probabilities, Multiplicities and Spectra of Secondaries
in High Energy Heavy Ion Interactions | 16 pages and 11 figures | null | null | null | hep-ph | null | We present a short review of theoretical results (mainly for
experimentalists) published in many different papers. The formulae are
presented for the different integrated cross sections, the number of
interacting nucleons, multiplicities of secondaries, the dispersions of
multiplicity distributions. Two possible tests for the search of Quark-Gluon
Plasma formation are discussed. CERN SPS data for production of secondaries in
central Pb+Pb collisions are compared with Quark-Gluon String Model
predictions.
| [
{
"created": "Thu, 12 Jul 2001 12:37:14 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"de Deus",
"J. Dias",
"",
"CENTRA, Instituto Superior\n Tecnico, Lisbon, Portugal"
],
[
"Shabelski",
"Yu. M.",
"",
"CENTRA, Instituto Superior\n Tecnico, Lisbon, Portugal"
]
] | We present a short review of theoretical results (mainly for experimentalists) published in many different papers. The formulae are presented for the different integrated cross sections, the number of interacting nucleons, multiplicities of secondaries, the dispersions of multiplicity distributions. Two possible tests for the search of Quark-Gluon Plasma formation are discussed. CERN SPS data for production of secondaries in central Pb+Pb collisions are compared with Quark-Gluon String Model predictions. |
1109.2940 | Martin Block | M. M. Block | Ultra-high Energy Predictions of Proton-Air Cross Sections from
Accelerator Data: an Update | 3 pages, 3 figures | null | 10.1103/PhysRevD.84.091501 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | At $\sqrt s = 57\pm 7$ TeV, the Pierre Auger Observatory (PAO) collaboration
has recently measured the proton-air inelastic production cross section
$\sigma_{\rm p-air}$. Assuming a helium contamination of 25%, they subtracted
30 mb from their measured value, resulting in a p-air inelastic production
cross section, $\sigma_{\rm p-air}=475 \pm 22\ ({\rm stat.})\pm^{20}_{15} \
({\rm syst.})$ mb, exclusive of helium contamination. Using this result in a
Glauber calculation to obtain the $pp$ inelastic cross section, they found the
inelastic $pp$ cross section $\sigma_{\rm inel}= 90\pm 7\ ({\rm stat.})
\pm^9_{11} ({\rm syst.}) \pm 1.5 {\rm \ (Glaub.})$ mb. Parameterization of the
$\bar pp$ and $pp$ cross sections incorporating analyticity constraints and
unitarity has allowed us to make accurate extrapolations to ultra-high
energies, and using Glauber calculations, accurately predict cosmic ray results
for $\spai$. In this update for 57 TeV, we predict i) a $pp$ total cross
section, $\sigma_{\rm tot}=133.4\pm 1.6$ mb, using high energy predictions from
a saturated Froissart bound parameterization of accelerator data on forward
$\bar pp$ and $pp$ scattering amplitudes and ii) a p-air inelastic production
cross section, $\sigma_{\rm p-air}=483\pm 3 $ mb, by using $\sigma_{\rm tot}$
together with Glauber theory, allowing us to determine independently that the
helium contamination was 19%, in reasonable agreement with their estimate of
25%. Our predictions agree with all available cosmic ray extensive air shower
measurements, both in magnitude and in energy dependence. By using our value
for the $pp$ total cross section at 57 TeV, Block and Halzen \cite{blackdisk}
have predicted that the $pp$ inelastic cross section is $\sigma_{\rm inel}=
92.9\pm 1.6$ mb, in agreement with the measured POA value.
| [
{
"created": "Tue, 13 Sep 2011 21:36:52 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Block",
"M. M.",
""
]
] | At $\sqrt s = 57\pm 7$ TeV, the Pierre Auger Observatory (PAO) collaboration has recently measured the proton-air inelastic production cross section $\sigma_{\rm p-air}$. Assuming a helium contamination of 25%, they subtracted 30 mb from their measured value, resulting in a p-air inelastic production cross section, $\sigma_{\rm p-air}=475 \pm 22\ ({\rm stat.})\pm^{20}_{15} \ ({\rm syst.})$ mb, exclusive of helium contamination. Using this result in a Glauber calculation to obtain the $pp$ inelastic cross section, they found the inelastic $pp$ cross section $\sigma_{\rm inel}= 90\pm 7\ ({\rm stat.}) \pm^9_{11} ({\rm syst.}) \pm 1.5 {\rm \ (Glaub.})$ mb. Parameterization of the $\bar pp$ and $pp$ cross sections incorporating analyticity constraints and unitarity has allowed us to make accurate extrapolations to ultra-high energies, and using Glauber calculations, accurately predict cosmic ray results for $\spai$. In this update for 57 TeV, we predict i) a $pp$ total cross section, $\sigma_{\rm tot}=133.4\pm 1.6$ mb, using high energy predictions from a saturated Froissart bound parameterization of accelerator data on forward $\bar pp$ and $pp$ scattering amplitudes and ii) a p-air inelastic production cross section, $\sigma_{\rm p-air}=483\pm 3 $ mb, by using $\sigma_{\rm tot}$ together with Glauber theory, allowing us to determine independently that the helium contamination was 19%, in reasonable agreement with their estimate of 25%. Our predictions agree with all available cosmic ray extensive air shower measurements, both in magnitude and in energy dependence. By using our value for the $pp$ total cross section at 57 TeV, Block and Halzen \cite{blackdisk} have predicted that the $pp$ inelastic cross section is $\sigma_{\rm inel}= 92.9\pm 1.6$ mb, in agreement with the measured POA value. |
2307.04691 | Valerie Fiona Domcke | Wilfried Buchmuller, Valerie Domcke, Kai Schmitz | Metastable cosmic strings | typo in normalization of S corrected, results unchanged | null | null | CERN-TH-2023-118, MS-TP-23-37, DESY-23-117 | hep-ph astro-ph.CO gr-qc | http://creativecommons.org/licenses/by/4.0/ | Many symmetry breaking patterns in grand unified theories (GUTs) give rise to
cosmic strings that eventually decay when pairs of GUT monopoles spontaneously
nucleate along the string cores. These strings are known as metastable cosmic
strings and have intriguing implications for particle physics and cosmology. In
this article, we discuss the current status of metastable cosmic strings, with
a focus on possible GUT embeddings and connections to inflation, neutrinos, and
gravitational waves (GWs). The GW signal emitted by a network of metastable
cosmic strings in the early universe differs, in particular, from the signal
emitted by topologically stable strings by a suppression at low frequencies.
Therefore, if the underlying symmetry breaking scale is close to the GUT scale,
the resulting GW spectrum can be accessible at current ground-based
interferometers as well as at future space-based interferometers, such as LISA,
and at the same time account for the signal in the most recent pulsar timing
data sets. Metastable cosmic strings thus nourish the hope that future GW
observations might shed light on fundamental physics close to the GUT scale.
| [
{
"created": "Mon, 10 Jul 2023 16:44:41 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Sep 2023 16:45:33 GMT",
"version": "v2"
},
{
"created": "Sat, 20 Jan 2024 18:05:26 GMT",
"version": "v3"
}
] | 2024-01-23 | [
[
"Buchmuller",
"Wilfried",
""
],
[
"Domcke",
"Valerie",
""
],
[
"Schmitz",
"Kai",
""
]
] | Many symmetry breaking patterns in grand unified theories (GUTs) give rise to cosmic strings that eventually decay when pairs of GUT monopoles spontaneously nucleate along the string cores. These strings are known as metastable cosmic strings and have intriguing implications for particle physics and cosmology. In this article, we discuss the current status of metastable cosmic strings, with a focus on possible GUT embeddings and connections to inflation, neutrinos, and gravitational waves (GWs). The GW signal emitted by a network of metastable cosmic strings in the early universe differs, in particular, from the signal emitted by topologically stable strings by a suppression at low frequencies. Therefore, if the underlying symmetry breaking scale is close to the GUT scale, the resulting GW spectrum can be accessible at current ground-based interferometers as well as at future space-based interferometers, such as LISA, and at the same time account for the signal in the most recent pulsar timing data sets. Metastable cosmic strings thus nourish the hope that future GW observations might shed light on fundamental physics close to the GUT scale. |
2408.00360 | Eduard Paryev Ph.D | E. Ya. Paryev | An alternative way to decipher the nature of the doubly charmed
tetraquark $T_{cc}(3875)^+$: its antiparticle $T_{{\bar c}{\bar c}}(3875)^-$
photoproduction off nuclei near threshold | 23 pages, 10 figures. arXiv admin note: substantial text overlap with
arXiv:2405.01089 | null | null | null | hep-ph hep-ex nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | We study the inclusive photoproduction of $T_{{\bar c}{\bar c}}(3875)^-$
mesons (which are the antiparticles of the doubly charmed tetraquarks
$T_{cc}(3875)^+$ discovered recently by the LHCb Collaboration) from nuclei in
the near-threshold energy region within the nuclear spectral function approach
by considering incoherent direct (${\gamma}p(n) \to D^+(D^0){T_{{\bar c}{\bar
c}}(3875)^-}\Lambda^+_c$) photon--nucleon $T_{{\bar c}{\bar c}}(3875)^-$
creation processes as well as five possible different scenarios for their
internal structure with the main goal of clarifying the possibility to decipher
this structure (and, hence, that of $T_{cc}(3875)^+$) in photoproduction via
integral and differential observables. We calculate the absolute and relative
excitation functions for $T_{{\bar c}{\bar c}}(3875)^-$ production off $^{12}$C
and $^{184}$W target nuclei at near-threshold photon beam energies of 30--38
GeV, the absolute differential cross sections for their production off these
target nuclei at laboratory polar angles of 0$^{\circ}$--10$^{\circ}$ as well
as the A and momentum dependences of the relative (transparency ratios) cross
sections for $T_{{\bar c}{\bar c}}(3875)^-$ production at photon energy of 35
GeV within the adopted scenarios for the $T_{{\bar c}{\bar c}}(3875)^-$ meson
intrinsic structure. We demonstrate that the absolute and relative observables
considered show a certain sensitivity to these scenarios. Therefore, the
measurement of such observables in future experiments at the proposed
high-luminosity electron-ion colliders EIC and EicC in the US and China in the
near-threshold energy region might shed light on the $T_{cc}(3875)^+$ internal
structure.
| [
{
"created": "Thu, 1 Aug 2024 08:01:54 GMT",
"version": "v1"
}
] | 2024-08-02 | [
[
"Paryev",
"E. Ya.",
""
]
] | We study the inclusive photoproduction of $T_{{\bar c}{\bar c}}(3875)^-$ mesons (which are the antiparticles of the doubly charmed tetraquarks $T_{cc}(3875)^+$ discovered recently by the LHCb Collaboration) from nuclei in the near-threshold energy region within the nuclear spectral function approach by considering incoherent direct (${\gamma}p(n) \to D^+(D^0){T_{{\bar c}{\bar c}}(3875)^-}\Lambda^+_c$) photon--nucleon $T_{{\bar c}{\bar c}}(3875)^-$ creation processes as well as five possible different scenarios for their internal structure with the main goal of clarifying the possibility to decipher this structure (and, hence, that of $T_{cc}(3875)^+$) in photoproduction via integral and differential observables. We calculate the absolute and relative excitation functions for $T_{{\bar c}{\bar c}}(3875)^-$ production off $^{12}$C and $^{184}$W target nuclei at near-threshold photon beam energies of 30--38 GeV, the absolute differential cross sections for their production off these target nuclei at laboratory polar angles of 0$^{\circ}$--10$^{\circ}$ as well as the A and momentum dependences of the relative (transparency ratios) cross sections for $T_{{\bar c}{\bar c}}(3875)^-$ production at photon energy of 35 GeV within the adopted scenarios for the $T_{{\bar c}{\bar c}}(3875)^-$ meson intrinsic structure. We demonstrate that the absolute and relative observables considered show a certain sensitivity to these scenarios. Therefore, the measurement of such observables in future experiments at the proposed high-luminosity electron-ion colliders EIC and EicC in the US and China in the near-threshold energy region might shed light on the $T_{cc}(3875)^+$ internal structure. |
0712.1012 | Wojciech Broniowski | Wojciech Broniowski, Enrique Ruiz Arriola, Krzysztof Golec-Biernat | Generalized parton distributions of the pion in chiral quark models and
their QCD evolution | 25 pages, 15 figures, added discussion of the end-point behavior | Phys.Rev.D77:034023,2008 | 10.1103/PhysRevD.77.034023 | null | hep-ph | null | We evaluate Generalized Parton Distributions of the pion in two chiral quark
models: the Spectral Quark Model and the Nambu-Jona-Lasinio model with a
Pauli-Villars regularization. We proceed by the evaluation of double
distributions through the use of a manifestly covariant calculation based on
the alpha representation of propagators. As a result polynomiality is
incorporated automatically and calculations become simple. In addition,
positivity and normalization constraints, sum rules and soft pion theorems are
fulfilled. We obtain explicit formulas, holding at the low-energy quark-model
scale. The expressions exhibit no factorization in the t-dependence. The QCD
evolution of those parton distributions is carried out to experimentally or
lattice accessible scales. We argue for the need of evolution by comparing the
Parton Distribution Function and the Parton Distribution Amplitude of the pion
to the available experimental and lattice data, and confirm that the
quark-model scale is low, about 320 MeV.
| [
{
"created": "Thu, 6 Dec 2007 17:55:20 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Jan 2008 18:06:00 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Broniowski",
"Wojciech",
""
],
[
"Arriola",
"Enrique Ruiz",
""
],
[
"Golec-Biernat",
"Krzysztof",
""
]
] | We evaluate Generalized Parton Distributions of the pion in two chiral quark models: the Spectral Quark Model and the Nambu-Jona-Lasinio model with a Pauli-Villars regularization. We proceed by the evaluation of double distributions through the use of a manifestly covariant calculation based on the alpha representation of propagators. As a result polynomiality is incorporated automatically and calculations become simple. In addition, positivity and normalization constraints, sum rules and soft pion theorems are fulfilled. We obtain explicit formulas, holding at the low-energy quark-model scale. The expressions exhibit no factorization in the t-dependence. The QCD evolution of those parton distributions is carried out to experimentally or lattice accessible scales. We argue for the need of evolution by comparing the Parton Distribution Function and the Parton Distribution Amplitude of the pion to the available experimental and lattice data, and confirm that the quark-model scale is low, about 320 MeV. |
1408.4392 | Dr. Rukmani Mohanta | Sruthilaya M., Soumya C., K. N. Deepthi, R. Mohanta | Predicting Leptonic CP phase by considering deviations in charged lepton
and neutrino sectors | 23 pages, 5 figures, revised version, to appear in New Journal of
Physics | null | 10.1088/1367-2630/17/8/083028 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, the reactor mixing angle $\theta_{13}$ has been measured precisely
by Daya Bay, RENO and T2K experiments with a moderately large value. However,
the standard form of neutrino mixing patterns such as bimaximal, tri-bimaximal,
golden ratio of types A and B, hexagonal etc., which are based on certain
flavor symmetries, predict vanishing $\theta_{13}$. Using the fact that the
neutrino mixing matrix can be represented as $V_{\rm PMNS}=U_l^{\dagger} U_\nu
P_\nu$, where $U_l$ and $U_\nu$ result from the diagonalization of the charged
lepton and neutrino mass matrices and $P_\nu$ is a diagonal matrix containing
Majorana phases, we explore the possibility of accounting for the large reactor
mixing angle by considering deviations both in the charged lepton and neutrino
sector. In the charged lepton sector we consider the deviation as an additional
rotation in the (12) and (13) planes, whereas in neutrino sector we consider
deviations to various neutrino mixing patterns through (13) and (23) rotations.
We find that with the inclusion of these deviations it is possible to
accommodate the observed large reactor mixing angle $\theta_{13}$, and one can
also obtain limits on the CP violating Dirac phase $\delta_{CP}$ and Jarlskog
invariant $J_{CP}$ for most of the cases. We then explore whether our findings
can be tested in the currently running NO$\nu$A experiment with 3 years of data
taking in neutrino mode followed by 3 years with anti-neutrino mode.
| [
{
"created": "Tue, 19 Aug 2014 16:52:28 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Jun 2015 06:07:32 GMT",
"version": "v2"
}
] | 2015-09-02 | [
[
"M.",
"Sruthilaya",
""
],
[
"C.",
"Soumya",
""
],
[
"Deepthi",
"K. N.",
""
],
[
"Mohanta",
"R.",
""
]
] | Recently, the reactor mixing angle $\theta_{13}$ has been measured precisely by Daya Bay, RENO and T2K experiments with a moderately large value. However, the standard form of neutrino mixing patterns such as bimaximal, tri-bimaximal, golden ratio of types A and B, hexagonal etc., which are based on certain flavor symmetries, predict vanishing $\theta_{13}$. Using the fact that the neutrino mixing matrix can be represented as $V_{\rm PMNS}=U_l^{\dagger} U_\nu P_\nu$, where $U_l$ and $U_\nu$ result from the diagonalization of the charged lepton and neutrino mass matrices and $P_\nu$ is a diagonal matrix containing Majorana phases, we explore the possibility of accounting for the large reactor mixing angle by considering deviations both in the charged lepton and neutrino sector. In the charged lepton sector we consider the deviation as an additional rotation in the (12) and (13) planes, whereas in neutrino sector we consider deviations to various neutrino mixing patterns through (13) and (23) rotations. We find that with the inclusion of these deviations it is possible to accommodate the observed large reactor mixing angle $\theta_{13}$, and one can also obtain limits on the CP violating Dirac phase $\delta_{CP}$ and Jarlskog invariant $J_{CP}$ for most of the cases. We then explore whether our findings can be tested in the currently running NO$\nu$A experiment with 3 years of data taking in neutrino mode followed by 3 years with anti-neutrino mode. |
1412.3823 | Wei Chao | Wei Chao | First order electroweak phase transition triggered by the Higgs portal
vector dark matter | 16 pages, 4 figures | Phys. Rev. D 92, 015025 (2015) | 10.1103/PhysRevD.92.015025 | ACFI-T14-26 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate an extension of the Standard Model (SM) with a U(1)' gauge
symmetry, which is spontaneously broken by a complex scalar singlet and where
the new gauge boson is a stable dark matter candidate via a Z2 flavor symmetry.
The possibility of generating a strongly first order electroweak phase
transition (EWPT) needed for the electroweak baryogenesis mechanism in this
model is studied using a gauge independent method. Our result shows a
considerable parameter space where both successful dark matter phenomenologies
and a strongly first order EWPT can be achieved.
| [
{
"created": "Thu, 11 Dec 2014 21:06:42 GMT",
"version": "v1"
}
] | 2015-07-29 | [
[
"Chao",
"Wei",
""
]
] | We investigate an extension of the Standard Model (SM) with a U(1)' gauge symmetry, which is spontaneously broken by a complex scalar singlet and where the new gauge boson is a stable dark matter candidate via a Z2 flavor symmetry. The possibility of generating a strongly first order electroweak phase transition (EWPT) needed for the electroweak baryogenesis mechanism in this model is studied using a gauge independent method. Our result shows a considerable parameter space where both successful dark matter phenomenologies and a strongly first order EWPT can be achieved. |
hep-ph/9904452 | Pere Talavere | Ll. Ametller (Barcelona, Polytechnic U), J. Kambor (Z\"urich U), M.
Knecht (Marseille, CPT) and P. Talavera (Lund U) | Low-energy photon-photon fusion into three pions in Generalized Chiral
Perturbation Theory | 33 pages, 5 postscript figures | Phys. Rev. D 60, 094003 (1999) | 10.1103/PhysRevD.60.094003 | CPT-98/P.3716, LU TP 98/23, ZU-TH 21/98 | hep-ph | null | The processes $\gamma\gamma\to\pi^0\pi^0\pi^0$ and $\gamma\gamma\to \pi^+
\pi^- \pi^0$ are considered in Generalized Chiral Perturbation theory, in view
of their potential sensitivity to the mechanism of spontaneous breaking of
chiral symmetry and to various counterterms. The amplitudes are computed up to
order ${\cal O}(p^6)$. The event production rates are estimated for the Daphne
$\phi$-Factory and for a future $\tau$-Charm Factory.
| [
{
"created": "Mon, 26 Apr 1999 11:13:25 GMT",
"version": "v1"
}
] | 2016-08-25 | [
[
"Ametller",
"Ll.",
"",
"Barcelona, Polytechnic U"
],
[
"Kambor",
"J.",
"",
"Zürich U"
],
[
"Knecht",
"M.",
"",
"Marseille, CPT"
],
[
"Talavera",
"P.",
"",
"Lund U"
]
] | The processes $\gamma\gamma\to\pi^0\pi^0\pi^0$ and $\gamma\gamma\to \pi^+ \pi^- \pi^0$ are considered in Generalized Chiral Perturbation theory, in view of their potential sensitivity to the mechanism of spontaneous breaking of chiral symmetry and to various counterterms. The amplitudes are computed up to order ${\cal O}(p^6)$. The event production rates are estimated for the Daphne $\phi$-Factory and for a future $\tau$-Charm Factory. |
hep-ph/9903462 | Manuel A. Valle | M. A. Valle Basagoiti | Collision Terms from Fluctuations in the HTL Theory for the Quark-Gluon
Plasma | 9 pages, no figures | null | null | null | hep-ph hep-th | null | Starting from the kinetic formulation of the hard thermal loop effective
theory, we have (re)derived the collision terms for soft modes of order $g^2 T
\log(1/g)$ by averaging the statistical fluctuations in the plasma.
| [
{
"created": "Tue, 23 Mar 1999 22:04:26 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Basagoiti",
"M. A. Valle",
""
]
] | Starting from the kinetic formulation of the hard thermal loop effective theory, we have (re)derived the collision terms for soft modes of order $g^2 T \log(1/g)$ by averaging the statistical fluctuations in the plasma. |
1307.8170 | Juergen Reuter | J. Reuter, W. Kilian, M. Sekulla | Simplified Models for New Physics in Vector Boson Scattering - Input for
Snowmass 2013 | A Snowmass White Paper, minor typos, one formula updated | null | null | DESY 13-132, SI-HEP-2013-06 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this contribution to the Snowmass process 2013 (which is a preliminary
version of [1]) we give a brief review of how new physics could enter in the
electroweak (EW) sector of the Standard Model (SM). This new physics, if it is
directly accessible at low energies, can be parameterized by explicit
resonances having certain quantum numbers. The extreme case is the decoupling
limit where those resonances are very heavy and leave only traces in the form
of deviations in the SM couplings. Translations are given into
higher-dimensional operators leading to such deviations. As long as such
resonances are introduced without a UV-complete theory behind it, these models
suffer from unitarity violation of perturbative scattering amplitudes. We show
explicitly how theoretically sane descriptions could be achieved by using a
unitarization prescription that allows a correct description of such a
resonance without specifying a UV-complete model.
| [
{
"created": "Tue, 30 Jul 2013 23:30:43 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Sep 2013 14:12:24 GMT",
"version": "v2"
}
] | 2013-09-06 | [
[
"Reuter",
"J.",
""
],
[
"Kilian",
"W.",
""
],
[
"Sekulla",
"M.",
""
]
] | In this contribution to the Snowmass process 2013 (which is a preliminary version of [1]) we give a brief review of how new physics could enter in the electroweak (EW) sector of the Standard Model (SM). This new physics, if it is directly accessible at low energies, can be parameterized by explicit resonances having certain quantum numbers. The extreme case is the decoupling limit where those resonances are very heavy and leave only traces in the form of deviations in the SM couplings. Translations are given into higher-dimensional operators leading to such deviations. As long as such resonances are introduced without a UV-complete theory behind it, these models suffer from unitarity violation of perturbative scattering amplitudes. We show explicitly how theoretically sane descriptions could be achieved by using a unitarization prescription that allows a correct description of such a resonance without specifying a UV-complete model. |
hep-ph/9208234 | Andre Pereira de Almeida | A. P. de Almeida and J. Frenkel | On the Infrared Behavior of the Pressure in Thermal Field Theories | 20 pages plus 4 figures available by request, IFUSP/P-1001 | Phys. Rev. D 47, 640 (1993) | 10.1103/PhysRevD.47.640 | null | hep-ph hep-th | null | We study non-perturbatively, via the Schwinger-Dyson equations, the leading
infrared behavior of the pressure in the ladder approximation. This problem is
discussed firstly in the context of a thermal scalar field theory, and the
analysis is then extended to the Yang-Mills theory at high temperatures. Using
the Feynman gauge, we find a system of two coupled integral equations for the
gluon and ghost self-energies, which is solved analytically. The solutions of
these equations show that the contributions to the pressure, when calculated in
the ladder approximation, are finite in the infrared domain.
| [
{
"created": "Wed, 19 Aug 1992 16:22:39 GMT",
"version": "v1"
}
] | 2013-11-13 | [
[
"de Almeida",
"A. P.",
""
],
[
"Frenkel",
"J.",
""
]
] | We study non-perturbatively, via the Schwinger-Dyson equations, the leading infrared behavior of the pressure in the ladder approximation. This problem is discussed firstly in the context of a thermal scalar field theory, and the analysis is then extended to the Yang-Mills theory at high temperatures. Using the Feynman gauge, we find a system of two coupled integral equations for the gluon and ghost self-energies, which is solved analytically. The solutions of these equations show that the contributions to the pressure, when calculated in the ladder approximation, are finite in the infrared domain. |
0802.0088 | Claude Semay | V. Mathieu, F. Buisseret, C. Semay | Gluons in glueballs: Spin or helicity? | 2 figures, section III.B corrected but conclusions unchanged | Phys.Rev.D77:114022,2008 | 10.1103/PhysRevD.77.114022 | null | hep-ph | null | In the last decade, lattice QCD has been able to compute the low-lying
glueball spectrum with accuracy. Like other effective approaches of QCD,
potential models still have difficulties to cope with gluonic hadrons. Assuming
that glueballs are bound states of valence gluons with zero current mass, it is
readily understood that the use of a potential model, intrinsically non
covariant, could be problematic in this case. The main challenge for this kind
of model is actually to find a way to introduce properly the more relevant
degree of freedom of the gluon: spin or helicity. In this work, we use the
so-called helicity formalism of Jacob and Wick to describe two-gluon glueballs.
We show in particular that this helicity formalism exactly reproduces the
$J^{PC}$ numbers which are observed in lattice QCD when the constituent gluons
have a helicity-1, without introducing extra states as it is the case in most
of the potential models. These extra states appear when gluons are seen as
spin-1 particles. Using a simple spinless Salpeter model with Cornell potential
within the helicity formalism, we obtain a glueball mass spectrum which is in
good agreement with lattice QCD predictions for helicity-1 gluons provided
instanton-induced interactions are taken into account.
| [
{
"created": "Fri, 1 Feb 2008 09:56:24 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Apr 2008 07:33:27 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Mathieu",
"V.",
""
],
[
"Buisseret",
"F.",
""
],
[
"Semay",
"C.",
""
]
] | In the last decade, lattice QCD has been able to compute the low-lying glueball spectrum with accuracy. Like other effective approaches of QCD, potential models still have difficulties to cope with gluonic hadrons. Assuming that glueballs are bound states of valence gluons with zero current mass, it is readily understood that the use of a potential model, intrinsically non covariant, could be problematic in this case. The main challenge for this kind of model is actually to find a way to introduce properly the more relevant degree of freedom of the gluon: spin or helicity. In this work, we use the so-called helicity formalism of Jacob and Wick to describe two-gluon glueballs. We show in particular that this helicity formalism exactly reproduces the $J^{PC}$ numbers which are observed in lattice QCD when the constituent gluons have a helicity-1, without introducing extra states as it is the case in most of the potential models. These extra states appear when gluons are seen as spin-1 particles. Using a simple spinless Salpeter model with Cornell potential within the helicity formalism, we obtain a glueball mass spectrum which is in good agreement with lattice QCD predictions for helicity-1 gluons provided instanton-induced interactions are taken into account. |
1808.08706 | Seyed Yaser Ayazi | Seyed Yaser Ayazi and Ahmad Mohamadnejad | Scale-Invariant Two Component Dark Matter | 22 pages, 14 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study a scale invariant extension of the standard model which can explain
simultaneously dark matter and the hierarchy problem. In our set-up, we
introduce a scalar and a spinor as two-component dark matter in addition to
scalon field as a mediator. Interesting point about our model is that due to
scale invariant conditions, compared to other two-component dark matter models,
it has lower independent parameters. Possible astrophysical and laboratory
signatures of two-component dark matter candidate are explored and it is shown
that the most contribution of observed relic density of dark matter can be
determined by spinor dark matter. Detectability of these dark matter particles
is studied and the direct and invisible Higgs decay experiments are used to
rule out part of the parameter space of the model. In addition, the dark matter
self-interactions are considered and shown that their contribution saturate
this constraint in the resonant regions.
| [
{
"created": "Mon, 27 Aug 2018 07:00:50 GMT",
"version": "v1"
}
] | 2018-08-28 | [
[
"Ayazi",
"Seyed Yaser",
""
],
[
"Mohamadnejad",
"Ahmad",
""
]
] | We study a scale invariant extension of the standard model which can explain simultaneously dark matter and the hierarchy problem. In our set-up, we introduce a scalar and a spinor as two-component dark matter in addition to scalon field as a mediator. Interesting point about our model is that due to scale invariant conditions, compared to other two-component dark matter models, it has lower independent parameters. Possible astrophysical and laboratory signatures of two-component dark matter candidate are explored and it is shown that the most contribution of observed relic density of dark matter can be determined by spinor dark matter. Detectability of these dark matter particles is studied and the direct and invisible Higgs decay experiments are used to rule out part of the parameter space of the model. In addition, the dark matter self-interactions are considered and shown that their contribution saturate this constraint in the resonant regions. |
1306.3291 | Swatantra Tiwari Kumar | S. K. Tiwari, and C. P. Singh | Particle production in Ultra-relativistic Heavy-Ion Collisions : A
Statistical-Thermal Model Review | 54 pages, 25 figures, Review Article, Accepted for Publication in
Advances in High Energy Physics for the special issue on "Multiparticle
production in High Energy Collisions" | Advances in High Energy Physics 2013, 805413 (2013) | 10.1155/2013/805413 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The current status of various thermal and statistical descriptions of
particle production in the ultra-relativistic heavy-ion collisions experiments
is presented in detail. We discuss the formulation of various types of thermal
models of a hot and dense hadron gas (HG) and the methods incorporated in
implementing the interactions between hadrons. We first obtain the
parameterization of center-of-mass energy ($\sqrt{s_{NN}}$) in terms of
temperature ($T$) and baryon chemical potential ($\mu_B$) obtained by analyzing
the particle ratios at the freeze-out over a broad energy range from the lowest
Alternating Gradient Synchrotron (AGS) energy to the highest Relativistic
Heavy-Ion Collider (RHIC) energies. The results of various thermal models
together with the experimental results for the various ratios of yields of
produced hadrons are then compared. We have derived some new universal
conditions emerging at the chemical freeze-out of HG fireball which demonstrate
the independence with respect to the energy as well as the structure of the
nuclei used in the collision. Further, we perform the calculation of various
transport properties of HG such as shear viscosity-to-entropy density ratio
($\eta/s$) etc. using thermal model and compare with the results of other
models. We also present the calculation of the rapidity as well as transverse
mass spectra of various hadrons in the thermal HG model. The purpose of this
review article is to organize and summarize the experimental data obtained in
various experiments with heavy-ion collisions and then to examine and analyze
them using thermal models so that a firm conclusion regarding the formation of
quark-gluon plasma (QGP) can be obtained.
| [
{
"created": "Fri, 14 Jun 2013 04:12:18 GMT",
"version": "v1"
},
{
"created": "Sun, 25 Aug 2013 05:28:51 GMT",
"version": "v2"
}
] | 2017-01-06 | [
[
"Tiwari",
"S. K.",
""
],
[
"Singh",
"C. P.",
""
]
] | The current status of various thermal and statistical descriptions of particle production in the ultra-relativistic heavy-ion collisions experiments is presented in detail. We discuss the formulation of various types of thermal models of a hot and dense hadron gas (HG) and the methods incorporated in implementing the interactions between hadrons. We first obtain the parameterization of center-of-mass energy ($\sqrt{s_{NN}}$) in terms of temperature ($T$) and baryon chemical potential ($\mu_B$) obtained by analyzing the particle ratios at the freeze-out over a broad energy range from the lowest Alternating Gradient Synchrotron (AGS) energy to the highest Relativistic Heavy-Ion Collider (RHIC) energies. The results of various thermal models together with the experimental results for the various ratios of yields of produced hadrons are then compared. We have derived some new universal conditions emerging at the chemical freeze-out of HG fireball which demonstrate the independence with respect to the energy as well as the structure of the nuclei used in the collision. Further, we perform the calculation of various transport properties of HG such as shear viscosity-to-entropy density ratio ($\eta/s$) etc. using thermal model and compare with the results of other models. We also present the calculation of the rapidity as well as transverse mass spectra of various hadrons in the thermal HG model. The purpose of this review article is to organize and summarize the experimental data obtained in various experiments with heavy-ion collisions and then to examine and analyze them using thermal models so that a firm conclusion regarding the formation of quark-gluon plasma (QGP) can be obtained. |
hep-ph/9403396 | Sean Fleming Northwestern Univ. | Sean Fleming | J/Psi Production from Electromagnetic Fragmentation in Z decay | 16 pages and 8 figures | Phys.Rev. D50 (1994) 5808-5815 | 10.1103/PhysRevD.50.5808 | FERMILAB-PUB-94/074-T NUHEP-TH-94-6 | hep-ph | null | The rate for $ Z^{0}\to J/ \psi + \ell^{+}\ell^{-} $ is suprisingly large
with about one event for every million $Z^{0}$ decays. The reason for this is
that there is a fragmentation contribution that is not suppressed by a factor
of $M^{2}_{\psi}/M^{2}_{Z}$. In the fragmentation limit $ M_{Z}\to\infty$ with
$E_{\psi}/M_{Z}$ fixed, the differential decay rate for $ Z^{0}\to J/ \psi +
\ell^{+}\ell^{-} $ factors into electromagnetic decay rates and universal
fragmentation functions. The fragmentation functions for lepton fragmentation
and photon fragmentation into $J/\psi$ are calculated to lowest order in
$\alpha$. The fragmentation approximation to the rate is shown to match the
full calculation for $E_{\psi}$ greater than about $3 M_{\psi}$.
| [
{
"created": "Wed, 30 Mar 1994 14:33:25 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Fleming",
"Sean",
""
]
] | The rate for $ Z^{0}\to J/ \psi + \ell^{+}\ell^{-} $ is suprisingly large with about one event for every million $Z^{0}$ decays. The reason for this is that there is a fragmentation contribution that is not suppressed by a factor of $M^{2}_{\psi}/M^{2}_{Z}$. In the fragmentation limit $ M_{Z}\to\infty$ with $E_{\psi}/M_{Z}$ fixed, the differential decay rate for $ Z^{0}\to J/ \psi + \ell^{+}\ell^{-} $ factors into electromagnetic decay rates and universal fragmentation functions. The fragmentation functions for lepton fragmentation and photon fragmentation into $J/\psi$ are calculated to lowest order in $\alpha$. The fragmentation approximation to the rate is shown to match the full calculation for $E_{\psi}$ greater than about $3 M_{\psi}$. |
1804.04270 | Kouhei Hasegawa | K. Hasegawa and C. S. Lim | Majorana neutrino masses in the scenario of gauge-Higgs unification | 13 pages, 2 figures, Update to match the version published at PTEP | Prog Theor Exp Phys (2018) | 10.1093/ptep/pty072 | KOBE-TH-18-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we consider possible mechanisms to generate small Majorana
neutrino masses for active neutrinos in the scenario of gauge-Higgs
unification, a candidate for physics beyond the standard model. We stress that
it is non-trivial to find a gauge-invariant operator, responsible for the
Majorana masses, which is the counterpart of the well-known SU(2)$_L \times$
U(1)$_Y$ invariant higher-mass-dimensional ($d = 5$) operator. As the first
possibility we discuss the seesaw mechanism by assigning leptonic fields to the
adjoint representation of the gauge group, so that a $d = 5$ gauge-invariant
operator can be formed. It turns out that the mechanism leading to the small
Majorana masses is the admixture of the Type I and Type III seesaw mechanisms.
As the second possibility, we consider the case where the relevant operator has
$d = 7$, by introducing a matter scalar belonging to the fundamental
representation of the gauge group. Reflecting the fact that the mass dimension
of the operator is higher than usually expected, the Majorana masses are
generated by a "double seesaw mechanism."
| [
{
"created": "Thu, 12 Apr 2018 01:26:37 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Sep 2018 05:11:58 GMT",
"version": "v2"
}
] | 2019-12-06 | [
[
"Hasegawa",
"K.",
""
],
[
"Lim",
"C. S.",
""
]
] | In this paper we consider possible mechanisms to generate small Majorana neutrino masses for active neutrinos in the scenario of gauge-Higgs unification, a candidate for physics beyond the standard model. We stress that it is non-trivial to find a gauge-invariant operator, responsible for the Majorana masses, which is the counterpart of the well-known SU(2)$_L \times$ U(1)$_Y$ invariant higher-mass-dimensional ($d = 5$) operator. As the first possibility we discuss the seesaw mechanism by assigning leptonic fields to the adjoint representation of the gauge group, so that a $d = 5$ gauge-invariant operator can be formed. It turns out that the mechanism leading to the small Majorana masses is the admixture of the Type I and Type III seesaw mechanisms. As the second possibility, we consider the case where the relevant operator has $d = 7$, by introducing a matter scalar belonging to the fundamental representation of the gauge group. Reflecting the fact that the mass dimension of the operator is higher than usually expected, the Majorana masses are generated by a "double seesaw mechanism." |
hep-ph/9504301 | null | A.V. Sidorov and D.B.Stamenov | "Fixed point" QCD Analysis of the CCFR Data on Deep Inelastic Neutrino-
Nucleon Scattering | 7 pages, LaTex | null | null | JINR E2-95-107 | hep-ph | null | The results of LO \it {Fixed Point} QCD (FP - QCD) analysis of the CCFR data
for the nucleon structure function $~xF_3(x,Q^2)~$ are presented. The predic-
tions of FP - QCD, in which $~\alpha_s(Q^2)~$ tends to a nonzero coupling
constant $~\alpha_0~$ as $~Q^2\to \infty~$, are in good agreement with the
data. The description of the data is even better than that in the case of LO
QCD. The FP-QCD parameter $~\alpha_0~$ is determined with a good accuracy:
$~\alpha_0 = 0.198\pm 0.009~$. Having in mind the recent QCD fits to the same
data we conclude that unlike the high precision and large $~(x,Q^2)~$ kinematic
range of the CCFR data they cannot discriminate between QCD and FP - QCD
predictions for $~xF_3(x,Q^2)~$.
| [
{
"created": "Fri, 14 Apr 1995 12:04:05 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Sidorov",
"A. V.",
""
],
[
"Stamenov",
"D. B.",
""
]
] | The results of LO \it {Fixed Point} QCD (FP - QCD) analysis of the CCFR data for the nucleon structure function $~xF_3(x,Q^2)~$ are presented. The predic- tions of FP - QCD, in which $~\alpha_s(Q^2)~$ tends to a nonzero coupling constant $~\alpha_0~$ as $~Q^2\to \infty~$, are in good agreement with the data. The description of the data is even better than that in the case of LO QCD. The FP-QCD parameter $~\alpha_0~$ is determined with a good accuracy: $~\alpha_0 = 0.198\pm 0.009~$. Having in mind the recent QCD fits to the same data we conclude that unlike the high precision and large $~(x,Q^2)~$ kinematic range of the CCFR data they cannot discriminate between QCD and FP - QCD predictions for $~xF_3(x,Q^2)~$. |
hep-ph/0507331 | Chong Sheng Li | Li Lin Yang, Chong Sheng Li, Jian Jun Liu, Qiang Li | Soft Gluon Resummation Effects in Single Slepton Production at Hadron
Colliders | 26 pages, 12 figures, RevTeX4; Minor changes; Version to appear in
PRD | Phys.Rev. D72 (2005) 074026 | 10.1103/PhysRevD.72.074026 | null | hep-ph | null | We investigate QCD effects in the production of a single slepton at hadron
colliders in the Minimal Supersymmetric Standard Model without R-parity. We
calculate the total cross sections and the transverse momentum distributions at
next-to-leading order in QCD. The NLO corrections enhance the total cross
sections and decrease the dependence of the total cross sections on the
factorization and renormalization scales. For the differential cross sections,
we resum all order soft gluon effects to give reliable predictions for the
transverse momentum distributions. We also compare two approaches to the
non-perturbative parametrization and found that the results are slightly
different at the Tevatron and are in good agreement at the LHC. Our results can
be useful to the simulation of the events and to the future collider
experiments.
| [
{
"created": "Fri, 29 Jul 2005 14:47:22 GMT",
"version": "v1"
},
{
"created": "Sun, 31 Jul 2005 05:50:52 GMT",
"version": "v2"
},
{
"created": "Sun, 2 Oct 2005 13:49:43 GMT",
"version": "v3"
}
] | 2009-11-11 | [
[
"Yang",
"Li Lin",
""
],
[
"Li",
"Chong Sheng",
""
],
[
"Liu",
"Jian Jun",
""
],
[
"Li",
"Qiang",
""
]
] | We investigate QCD effects in the production of a single slepton at hadron colliders in the Minimal Supersymmetric Standard Model without R-parity. We calculate the total cross sections and the transverse momentum distributions at next-to-leading order in QCD. The NLO corrections enhance the total cross sections and decrease the dependence of the total cross sections on the factorization and renormalization scales. For the differential cross sections, we resum all order soft gluon effects to give reliable predictions for the transverse momentum distributions. We also compare two approaches to the non-perturbative parametrization and found that the results are slightly different at the Tevatron and are in good agreement at the LHC. Our results can be useful to the simulation of the events and to the future collider experiments. |
hep-ph/0703063 | Cristina Volpe | R. Lazauskas, A.B. Balantekin, J.H. De Jesus, C. Volpe | Low-energy neutrinos at off-axis from a standard beta-beam | 9 pages, 6 figures | Phys.Rev.D76:053006,2007 | 10.1103/PhysRevD.76.053006 | null | hep-ph hep-ex nucl-ex nucl-th | null | We discuss a scenario to extract up to 150 MeV neutrinos at a standard
beta-beam facility using one and two detectors off-axis. In particular we show
that the high-energy component of the neutrino fluxes can be subtracted through
a specific combination of the response of two off-axis detectors. A systematic
analysis of the neutrino fluxes using different detector geometries is
presented, as well as a comparison with the expected fluxes at a low-energy
beta-beam facility. The presented option could offer an alternative way to
perform low-energy neutrino experiments.
| [
{
"created": "Tue, 6 Mar 2007 09:24:15 GMT",
"version": "v1"
},
{
"created": "Sun, 2 Sep 2007 08:08:52 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Lazauskas",
"R.",
""
],
[
"Balantekin",
"A. B.",
""
],
[
"De Jesus",
"J. H.",
""
],
[
"Volpe",
"C.",
""
]
] | We discuss a scenario to extract up to 150 MeV neutrinos at a standard beta-beam facility using one and two detectors off-axis. In particular we show that the high-energy component of the neutrino fluxes can be subtracted through a specific combination of the response of two off-axis detectors. A systematic analysis of the neutrino fluxes using different detector geometries is presented, as well as a comparison with the expected fluxes at a low-energy beta-beam facility. The presented option could offer an alternative way to perform low-energy neutrino experiments. |
1608.01999 | Frank Tackmann | Shireen Gangal, Jonathan R. Gaunt, Maximilian Stahlhofen, and Frank J.
Tackmann | Two-Loop Beam and Soft Functions for Rapidity-Dependent Jet Vetoes | 34 pages, 1 figure, v2: journal version + fixed typos in eqs. (1.2)
and (3.6), corrected c1 coefficients for TauBj in table 2 | null | 10.1007/JHEP02(2017)026 | MITP/16-078, DESY 16-154, NIKHEF 2016-032 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Jet vetoes play an important role in many analyses at the LHC. Traditionally,
jet vetoes have been imposed using a restriction on the transverse momentum
$p_{Tj}$ of jets. Alternatively, one can also consider jet observables for
which $p_{Tj}$ is weighted by a smooth function of the jet rapidity $y_j$ that
vanishes as $|y_j| \to \infty$. Such observables are useful as they provide a
natural way to impose a tight veto on central jets but a looser one at forward
rapidities. We consider two such rapidity-dependent jet veto observables,
$\mathcal{T}_{Bj}$ and $\mathcal{T}_{Cj}$, and compute the required beam and
dijet soft functions for the jet-vetoed color-singlet production cross section
at two loops. At this order, clustering effects from the jet algorithm become
important. The dominant contributions are computed fully analytically while
corrections that are subleading in the limit of small jet radii are expressed
in terms of finite numerical integrals. Our results enable the full NNLL'
resummation and are an important step towards N3LL resummation for cross
sections with a $\mathcal{T}_{Bj}$ or $\mathcal{T}_{Cj}$ jet veto.
| [
{
"created": "Fri, 5 Aug 2016 20:00:03 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Mar 2020 10:34:38 GMT",
"version": "v2"
}
] | 2020-03-20 | [
[
"Gangal",
"Shireen",
""
],
[
"Gaunt",
"Jonathan R.",
""
],
[
"Stahlhofen",
"Maximilian",
""
],
[
"Tackmann",
"Frank J.",
""
]
] | Jet vetoes play an important role in many analyses at the LHC. Traditionally, jet vetoes have been imposed using a restriction on the transverse momentum $p_{Tj}$ of jets. Alternatively, one can also consider jet observables for which $p_{Tj}$ is weighted by a smooth function of the jet rapidity $y_j$ that vanishes as $|y_j| \to \infty$. Such observables are useful as they provide a natural way to impose a tight veto on central jets but a looser one at forward rapidities. We consider two such rapidity-dependent jet veto observables, $\mathcal{T}_{Bj}$ and $\mathcal{T}_{Cj}$, and compute the required beam and dijet soft functions for the jet-vetoed color-singlet production cross section at two loops. At this order, clustering effects from the jet algorithm become important. The dominant contributions are computed fully analytically while corrections that are subleading in the limit of small jet radii are expressed in terms of finite numerical integrals. Our results enable the full NNLL' resummation and are an important step towards N3LL resummation for cross sections with a $\mathcal{T}_{Bj}$ or $\mathcal{T}_{Cj}$ jet veto. |
1609.07422 | Mohammad Moosavi Nejad | S. M. Moosavi Nejad, P. Sartipi Yarahmadi | Heavy quark fragmentation functions at next-to-leading perturbative QCD | null | Eur.Phys.J. A52 (2016), 315 | 10.1140/epja/i2016-16315-7 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is well-known that the dominant mechanism to produce hadronic bound states
with large transverse momentum is fragmentation. This mechanism is described by
the fragmentation functions (FFs) which are the universal and
process-independent functions. Here, we review the perturbative FFs formalism
as an appropriate tool for studying these hadronization processes and detail
the extension of this formalism at next-to-leading order (NLO). Using the
Suzuki's model, we calculate the perturbative QCD FF for a heavy quark to
fragment into a S-wave heavy meson at NLO. As an example, we study the LO and
NLO FFs for a charm quark to split into the S-wave $D$-meson and compare our
analytic results both with experimental data and well-known phenomenological
models.
| [
{
"created": "Fri, 23 Sep 2016 16:30:26 GMT",
"version": "v1"
}
] | 2016-10-19 | [
[
"Nejad",
"S. M. Moosavi",
""
],
[
"Yarahmadi",
"P. Sartipi",
""
]
] | It is well-known that the dominant mechanism to produce hadronic bound states with large transverse momentum is fragmentation. This mechanism is described by the fragmentation functions (FFs) which are the universal and process-independent functions. Here, we review the perturbative FFs formalism as an appropriate tool for studying these hadronization processes and detail the extension of this formalism at next-to-leading order (NLO). Using the Suzuki's model, we calculate the perturbative QCD FF for a heavy quark to fragment into a S-wave heavy meson at NLO. As an example, we study the LO and NLO FFs for a charm quark to split into the S-wave $D$-meson and compare our analytic results both with experimental data and well-known phenomenological models. |
2406.08313 | Chu-Wen Xiao | C. W. Xiao and J. J. Wu | Searching for bound states in the open strangeness systems | More comments added | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Inspired by the recent findings of $Z_{cs}$ and $P_{cs}$ states, we
investigate the strong interactions of the systems with open strangeness(es)
from the light sector to the heavy sector (no beauty quark), where the
interaction potential is derived from the vector meson exchange mechanism in
$t$- and $u$-channels. In the current work, we discuss all of single channel
cases for the open strangeness in the systemic framework, where the resonances
$X_0(2866)$, $D^*_{s0}(2317)$ and $D_{s1}(2460)$ are dynamically generated.
Furthermore, there are many new exotics predicted. In addition, the left-hand
cut problem in $t$- and $u$-channels is discussed in detail.
| [
{
"created": "Wed, 12 Jun 2024 15:14:41 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Jun 2024 12:59:27 GMT",
"version": "v2"
}
] | 2024-06-21 | [
[
"Xiao",
"C. W.",
""
],
[
"Wu",
"J. J.",
""
]
] | Inspired by the recent findings of $Z_{cs}$ and $P_{cs}$ states, we investigate the strong interactions of the systems with open strangeness(es) from the light sector to the heavy sector (no beauty quark), where the interaction potential is derived from the vector meson exchange mechanism in $t$- and $u$-channels. In the current work, we discuss all of single channel cases for the open strangeness in the systemic framework, where the resonances $X_0(2866)$, $D^*_{s0}(2317)$ and $D_{s1}(2460)$ are dynamically generated. Furthermore, there are many new exotics predicted. In addition, the left-hand cut problem in $t$- and $u$-channels is discussed in detail. |
1010.0890 | Francesco D'Eramo | Francesco D'Eramo, Hong Liu, Krishna Rajagopal | Jet Quenching Parameter via Soft Collinear Effective Theory (SCET) | 6 pages, 2 figures - Talk presented by F. D'Eramo at Jets in
Proton-Proton and Heavy-Ion Collisions, August 12-14, 2010, Prague, Czech
Republic | Int.J.Mod.Phys.E20:1610-1615,2011 | 10.1142/S0218301311019969 | MIT-CTP 4180 | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the transverse momentum broadening in the absence of radiation of
an energetic parton propagating through quark-gluon plasma via Soft Collinear
Effective Theory (SCET). We show that the probability for picking up transverse
momentum k_\perp is given by the Fourier transform of the expectation value of
two transversely separated light-like path-ordered Wilson lines. The subtleties
about the ordering of operators do not change the \hat q value for the strongly
coupled plasma of N=4 SYM theory.
| [
{
"created": "Tue, 5 Oct 2010 14:09:27 GMT",
"version": "v1"
}
] | 2011-07-28 | [
[
"D'Eramo",
"Francesco",
""
],
[
"Liu",
"Hong",
""
],
[
"Rajagopal",
"Krishna",
""
]
] | We analyze the transverse momentum broadening in the absence of radiation of an energetic parton propagating through quark-gluon plasma via Soft Collinear Effective Theory (SCET). We show that the probability for picking up transverse momentum k_\perp is given by the Fourier transform of the expectation value of two transversely separated light-like path-ordered Wilson lines. The subtleties about the ordering of operators do not change the \hat q value for the strongly coupled plasma of N=4 SYM theory. |
1607.06355 | Lei Wu | Lei Wu, Bingfang Yang, Mengchao Zhang | Little Higgs Dark Matter after PandaX-II/LUX 2016 and LHC Run-1 | discussions added, version accepted by JHEP | null | 10.1007/JHEP12(2016)152 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the Littlest Higgs model with $T$ parity (LHT), the $T$-odd heavy photon
($A_H$) is weakly interacting and can play the role of dark matter. We
investigate the lower limit on the mass of $A_H$ dark matter under the
constraints from Higgs data, EWPOs, $R_b$, Planck 2015 dark matter relic
abundance, PandaX-II/LUX 2016 direct detections and LHC-8 TeV monojet results.
We find that (1) Higgs data, EWPOs and $R_b$ can exclude the mass of $A_H$ up
to 99 GeV. To produce the correct dark matter relic abundance, $A_H$ has to
co-annihilate with $T$-odd quarks ($q_H$) or leptons ($\ell_H$); (2) the LUX
(PandaX-II) 2016 data can further exclude $m_{A_H}<380 (270)$ GeV for
$\ell_H$-$A_H$ co-annihilation and $m_{A_H}<350 (240)$ GeV for $q_H-A_H$
co-annihilation; (3) LHC-8 TeV monojet result can give a strong lower limit,
$m_{A_H}>540$ GeV, for $q_H$-$A_H$ co-annihilation; (4) future XENON1T (2017)
experiment can fully cover the parameter space of $\ell_H$-$A_H$
co-annihilation and will push the lower limit of $m_{A_H}$ up to about 640 GeV
for $q_H$-$A_H$ co-annihilation.
| [
{
"created": "Thu, 21 Jul 2016 15:08:57 GMT",
"version": "v1"
},
{
"created": "Sat, 23 Jul 2016 15:43:46 GMT",
"version": "v2"
},
{
"created": "Wed, 28 Dec 2016 11:25:23 GMT",
"version": "v3"
}
] | 2017-02-01 | [
[
"Wu",
"Lei",
""
],
[
"Yang",
"Bingfang",
""
],
[
"Zhang",
"Mengchao",
""
]
] | In the Littlest Higgs model with $T$ parity (LHT), the $T$-odd heavy photon ($A_H$) is weakly interacting and can play the role of dark matter. We investigate the lower limit on the mass of $A_H$ dark matter under the constraints from Higgs data, EWPOs, $R_b$, Planck 2015 dark matter relic abundance, PandaX-II/LUX 2016 direct detections and LHC-8 TeV monojet results. We find that (1) Higgs data, EWPOs and $R_b$ can exclude the mass of $A_H$ up to 99 GeV. To produce the correct dark matter relic abundance, $A_H$ has to co-annihilate with $T$-odd quarks ($q_H$) or leptons ($\ell_H$); (2) the LUX (PandaX-II) 2016 data can further exclude $m_{A_H}<380 (270)$ GeV for $\ell_H$-$A_H$ co-annihilation and $m_{A_H}<350 (240)$ GeV for $q_H-A_H$ co-annihilation; (3) LHC-8 TeV monojet result can give a strong lower limit, $m_{A_H}>540$ GeV, for $q_H$-$A_H$ co-annihilation; (4) future XENON1T (2017) experiment can fully cover the parameter space of $\ell_H$-$A_H$ co-annihilation and will push the lower limit of $m_{A_H}$ up to about 640 GeV for $q_H$-$A_H$ co-annihilation. |
hep-ph/0007207 | Antonio D. Polosa | R. Gatto, G. Nardulli, A.D. Polosa and N.A. Tornqvist | Predicting D -> sigma pi | 6 pages, RevTex, One new contribution added, typos corrected | Phys.Lett. B494 (2000) 168-174 | 10.1016/S0370-2693(00)01179-5 | UGVA-DPT/2000-07-1086 | hep-ph | null | We examine the D -> sigma pi amplitude through a constituent quark-meson
model, incorporating heavy quark and chiral symmetries, finding a good
agreement with the recent E791 data analysis of D -> 3 pi via sigma.
| [
{
"created": "Wed, 19 Jul 2000 12:37:52 GMT",
"version": "v1"
},
{
"created": "Sat, 16 Sep 2000 10:09:57 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Gatto",
"R.",
""
],
[
"Nardulli",
"G.",
""
],
[
"Polosa",
"A. D.",
""
],
[
"Tornqvist",
"N. A.",
""
]
] | We examine the D -> sigma pi amplitude through a constituent quark-meson model, incorporating heavy quark and chiral symmetries, finding a good agreement with the recent E791 data analysis of D -> 3 pi via sigma. |
2405.07003 | Soumen Kumar Manna | Arghyajit Datta, Soumen Kumar Manna, Arunansu Sil | Spontaneous Leptogenesis with sub-GeV Axion Like Particles | 8 pages, 2 figures, 1 table | null | null | null | hep-ph astro-ph.CO astro-ph.HE hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A derivative coupling of an axion like particle (ALP) with a B-L current may
lead to the baryon asymmetry of the universe via spontaneous leptogenesis
provided a lepton number breaking interaction prevails in thermal equilibrium.
Conventionally, such scenario works only for heavy ALPs and high reheating
temperature due to the fact that the same lepton number breaking contribution
is tied up with neutrino mass generation also. In this work, we propose inert
Higgs doublet assisted lepton number violating operator to relieve such tension
so as to generate lepton asymmetry (of freeze-in/out type) with a much lower
reheating temperature that can accommodate light (sub-GeV) ALPs sensitive to
current and future ALP searches.
| [
{
"created": "Sat, 11 May 2024 12:55:04 GMT",
"version": "v1"
},
{
"created": "Fri, 24 May 2024 07:15:47 GMT",
"version": "v2"
}
] | 2024-05-27 | [
[
"Datta",
"Arghyajit",
""
],
[
"Manna",
"Soumen Kumar",
""
],
[
"Sil",
"Arunansu",
""
]
] | A derivative coupling of an axion like particle (ALP) with a B-L current may lead to the baryon asymmetry of the universe via spontaneous leptogenesis provided a lepton number breaking interaction prevails in thermal equilibrium. Conventionally, such scenario works only for heavy ALPs and high reheating temperature due to the fact that the same lepton number breaking contribution is tied up with neutrino mass generation also. In this work, we propose inert Higgs doublet assisted lepton number violating operator to relieve such tension so as to generate lepton asymmetry (of freeze-in/out type) with a much lower reheating temperature that can accommodate light (sub-GeV) ALPs sensitive to current and future ALP searches. |
1312.5230 | Nikolaos Mavromatos | Nick E. Mavromatos and Sarben Sarkar | Neutrinos in the Early Universe, Kalb-Ramond Torsion and
Matter-Antimatter Asymmetry | 12 pages latex, uses special macros of the EPJ Web of Conference,
based on plenary talk by N.E.M. in 2nd International Conference on New
Frontiers in Physics 2013, Kolymbari Greece | null | 10.1051/epjconf/20147100085 | KCL-PH-TH/2013-45, LCTS/2013-34 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The generation of a matter-antimatter asymmetry in the Universe may be
induced by the propagation of fermions in non-trivial, spherically asymmetric
(and hence Lorentz violating) gravitational backgrounds. Such backgrounds may
characterise the epoch of the early universe. The key point in these models is
that the background induces different dispersion relations, hence populations,
between fermions and antifermions, and thus CPT Violation (CPTV) appears in
thermal equilibrium. Species populations may freeze out leading to leptogenesis
and baryogenesis. We consider here a string-inspired scenario, in which the
CPTV is associated with a cosmological background with torsion provided by the
Kalb-Ramond (KR) antisymemtric tensor field of the string gravitational
multiplet. In a four-dimensional space time this field is dual to a
pseudoscalar ``axion-like'' field. The mixing of the KR field with an ordinary
axion field can lead to the generation of a Majorana neutrino mass.
| [
{
"created": "Wed, 18 Dec 2013 17:17:14 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Mavromatos",
"Nick E.",
""
],
[
"Sarkar",
"Sarben",
""
]
] | The generation of a matter-antimatter asymmetry in the Universe may be induced by the propagation of fermions in non-trivial, spherically asymmetric (and hence Lorentz violating) gravitational backgrounds. Such backgrounds may characterise the epoch of the early universe. The key point in these models is that the background induces different dispersion relations, hence populations, between fermions and antifermions, and thus CPT Violation (CPTV) appears in thermal equilibrium. Species populations may freeze out leading to leptogenesis and baryogenesis. We consider here a string-inspired scenario, in which the CPTV is associated with a cosmological background with torsion provided by the Kalb-Ramond (KR) antisymemtric tensor field of the string gravitational multiplet. In a four-dimensional space time this field is dual to a pseudoscalar ``axion-like'' field. The mixing of the KR field with an ordinary axion field can lead to the generation of a Majorana neutrino mass. |
hep-ph/9710485 | Dan-Di Wu | Dan-Di Wu (Prairie View A&M University) | Exploring inconsistencies with the Cabibbo-Kobayashi-Maskawa model | Latex file, 12 pages, 2 tables. Added footnote 2 and minor
typo/wording corrections | null | null | Prairie View A&M, HEP-7-97 | hep-ph | null | A small upper-bound is obtained for the CP phase $\delta$ in a CKM matrix,
$|\sin\delta| \le 0.44$ based on CP independent data on $|V_{ub}/V_{cb}|$
alone. Potential inconsistencies with the CKM model in existing data which need
a theory beyond the standard model to overcome emerge in the analysis using
this CKM matrix. In addition, all CP asymmetry measurables for the $B_d- \bar
B_d$ system are expressed solely by the CP phases in the decay amplitudes.
Remarkably the CP asymmetry of the bench mark process $B_d\to \psi K_S$ equals
sin$2\delta$. This will soon be measured by BaBar and Belle to confront the
above upper-bound.
| [
{
"created": "Mon, 27 Oct 1997 17:32:12 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Oct 1997 17:30:08 GMT",
"version": "v2"
},
{
"created": "Mon, 8 Dec 1997 17:10:09 GMT",
"version": "v3"
},
{
"created": "Tue, 9 Dec 1997 19:26:12 GMT",
"version": "v4"
}
] | 2007-05-23 | [
[
"Wu",
"Dan-Di",
"",
"Prairie View A&M University"
]
] | A small upper-bound is obtained for the CP phase $\delta$ in a CKM matrix, $|\sin\delta| \le 0.44$ based on CP independent data on $|V_{ub}/V_{cb}|$ alone. Potential inconsistencies with the CKM model in existing data which need a theory beyond the standard model to overcome emerge in the analysis using this CKM matrix. In addition, all CP asymmetry measurables for the $B_d- \bar B_d$ system are expressed solely by the CP phases in the decay amplitudes. Remarkably the CP asymmetry of the bench mark process $B_d\to \psi K_S$ equals sin$2\delta$. This will soon be measured by BaBar and Belle to confront the above upper-bound. |
1507.02582 | Rome Samanta | Rome Samanta and Ambar Ghosal | Probing maximal zero textures with broken cyclic symmetry in inverse
seesaw | 14 pages, 19 figures, 6 tables, To appear in NPB | null | 10.1016/j.nuclphysb.2016.08.036 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Within the framework of inverse seesaw mechanism we investigate neutrino mass
matrices invariant under cyclic symmetry ($Z_3$) with maximal zero texture (6
zero textures). We explore two different approaches to obtain the cyclic
symmetry invariant form of the constituent matrices. In the first one we
consider explicit cyclic symmetry in the neutrino sector of the Lagrangian
which dictates the emerged effective neutrino mass matrix ($m_\nu$) to be
symmetry invariant and hence leads to a degeneracy in masses. We then consider
explicit breaking of the symmetry through a dimensionless parameter
$\epsilon^{\prime}$ to remove the degeneracy. It is seen that the method
doesn't support the current neutrino oscillation global fit data even after
considering the correction from cyclic symmetry invariant charged lepton mass
matrix ($m_l$) unless the breaking parameter is too large. In the second
method, we assume the same forms of the neutrino mass matrices, however,
symmetry is broken in the charged lepton sector. All the structures of the mass
matrices are now dictated by an effective residual symmetry of some larger
symmetry group in the Lagrangian. For illustration, we exemplify a toy model
based on softly broken $A_4$ symmetry group which leads to one of the
combination of $m_l$, $m_D$, $M_{RS}$ and $\mu$ to generate effective $m_\nu$.
All the emerged mass matrices predict a constraint range of the CP violating
phases and atmospheric mixing angle along with an inverted hierarchical
structure of the neutrino masses. Further, significant predictions on
$\beta\beta0\nu$ decay parameter $|m_{11}|$ and the sum of the three light
neutrino masses ($\Sigma_im_i$) are also obtained.
| [
{
"created": "Thu, 9 Jul 2015 16:31:42 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Aug 2016 11:19:48 GMT",
"version": "v2"
}
] | 2016-10-12 | [
[
"Samanta",
"Rome",
""
],
[
"Ghosal",
"Ambar",
""
]
] | Within the framework of inverse seesaw mechanism we investigate neutrino mass matrices invariant under cyclic symmetry ($Z_3$) with maximal zero texture (6 zero textures). We explore two different approaches to obtain the cyclic symmetry invariant form of the constituent matrices. In the first one we consider explicit cyclic symmetry in the neutrino sector of the Lagrangian which dictates the emerged effective neutrino mass matrix ($m_\nu$) to be symmetry invariant and hence leads to a degeneracy in masses. We then consider explicit breaking of the symmetry through a dimensionless parameter $\epsilon^{\prime}$ to remove the degeneracy. It is seen that the method doesn't support the current neutrino oscillation global fit data even after considering the correction from cyclic symmetry invariant charged lepton mass matrix ($m_l$) unless the breaking parameter is too large. In the second method, we assume the same forms of the neutrino mass matrices, however, symmetry is broken in the charged lepton sector. All the structures of the mass matrices are now dictated by an effective residual symmetry of some larger symmetry group in the Lagrangian. For illustration, we exemplify a toy model based on softly broken $A_4$ symmetry group which leads to one of the combination of $m_l$, $m_D$, $M_{RS}$ and $\mu$ to generate effective $m_\nu$. All the emerged mass matrices predict a constraint range of the CP violating phases and atmospheric mixing angle along with an inverted hierarchical structure of the neutrino masses. Further, significant predictions on $\beta\beta0\nu$ decay parameter $|m_{11}|$ and the sum of the three light neutrino masses ($\Sigma_im_i$) are also obtained. |
hep-ph/9801271 | null | G.F. Giudice, R. Rattazzi | Theories with Gauge-Mediated Supersymmetry Breaking | Several minor changes; new appendix with complete analytical formulae
for the mass spectrum in gauge mediation at the next-to-leading order | Phys.Rept. 322 (1999) 419-499 | 10.1016/S0370-1573(99)00042-3 | null | hep-ph hep-th | null | Theories with gauge-mediated supersymmetry breaking provide an interesting
alternative to the scenario in which the soft terms of the low-energy fields
are induced by gravity. These theories allow for a natural suppression of
flavour violations in the supersymmetric sector and have very distinctive
phenomenological features. Here we review their basic structure, their
experimental implications, and the attempts to embed them into models in which
all mass scales are dynamically generated from a single fundamental scale.
| [
{
"created": "Mon, 12 Jan 1998 17:20:02 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Apr 1999 12:37:20 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Giudice",
"G. F.",
""
],
[
"Rattazzi",
"R.",
""
]
] | Theories with gauge-mediated supersymmetry breaking provide an interesting alternative to the scenario in which the soft terms of the low-energy fields are induced by gravity. These theories allow for a natural suppression of flavour violations in the supersymmetric sector and have very distinctive phenomenological features. Here we review their basic structure, their experimental implications, and the attempts to embed them into models in which all mass scales are dynamically generated from a single fundamental scale. |
0910.3446 | Sanjoy Biswas | Sanjoy Biswas and Biswarup Mukhopadhyaya | Chargino reconstruction in supersymmetry with long-lived staus | 27 pages, 6 figures and 3 tables | Phys.Rev.D81:015003,2010 | 10.1103/PhysRevD.81.015003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a supersymmetric (SUSY) scenario including right-handed
neutrinos, one of whose scalar superpartners is the lightest SUSY particle
(LSP). The distinguishing feature in the collider signal of SUSY in such a case
is not missing energy but a pair of charged tracks corresponding to the
next-to- lightest SUSY particle, when it is, as in the case considered, a stau.
Following up on our recent work on neutralino reconstruction in such cases, we
explore the possibility of reconstructing charginos, too, through a study of
transverse mass distributions in specified final states. The various steps of
isolating the transverse momenta of neutrinos relevant for this are outlined,
and regions of the parameter space where our procedure works are identified.
| [
{
"created": "Mon, 19 Oct 2009 03:29:25 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Biswas",
"Sanjoy",
""
],
[
"Mukhopadhyaya",
"Biswarup",
""
]
] | We consider a supersymmetric (SUSY) scenario including right-handed neutrinos, one of whose scalar superpartners is the lightest SUSY particle (LSP). The distinguishing feature in the collider signal of SUSY in such a case is not missing energy but a pair of charged tracks corresponding to the next-to- lightest SUSY particle, when it is, as in the case considered, a stau. Following up on our recent work on neutralino reconstruction in such cases, we explore the possibility of reconstructing charginos, too, through a study of transverse mass distributions in specified final states. The various steps of isolating the transverse momenta of neutrinos relevant for this are outlined, and regions of the parameter space where our procedure works are identified. |
2203.16196 | Jason Aebischer | Jason Aebischer, Benjam\'in Grinstein | $\tau_{B_c}$ in the Standard Model | 7 pages, 1 figure, Contribution to the proceedings of the Corfu
Summer Institute 2021 "School and Workshops on Elementary Particle Physics
and Gravity", 29 August - 9 October 2021, Corfu, Greece | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model prediction of the $B_c$ lifetime is discussed, together
with the dominant uncertainties and strategies on how to improve them.
Furthermore, a new method to compute the $B_c$ lifetime based on the operator
product expansion is proposed. It relies on differences of $B,\,D$ and $B_c$
meson decay rates, in which the free-quark contributions cancel out, reducing
the uncertainty of the theory prediction.
| [
{
"created": "Wed, 30 Mar 2022 10:35:11 GMT",
"version": "v1"
}
] | 2022-03-31 | [
[
"Aebischer",
"Jason",
""
],
[
"Grinstein",
"Benjamín",
""
]
] | The Standard Model prediction of the $B_c$ lifetime is discussed, together with the dominant uncertainties and strategies on how to improve them. Furthermore, a new method to compute the $B_c$ lifetime based on the operator product expansion is proposed. It relies on differences of $B,\,D$ and $B_c$ meson decay rates, in which the free-quark contributions cancel out, reducing the uncertainty of the theory prediction. |
hep-ph/9604238 | Alexander Ignatiev | A.Yu.Ignatiev and G.C.Joshi | Possible electric charge nonconservation and dequantization in $SU(2)
\times U(1)$ models with hard symmetry breaking | 10 pages, revtex, no figures, to appear in Physics Letters B | Phys.Lett. B381 (1996) 216-220 | 10.1016/0370-2693(96)00569-2 | UM-P-95/113, RCHEP-95/25 | hep-ph | null | We study a novel type of extensions of the Standard Model which include a
hard mass term for the U(1) gauge field and, optionally, the additional scalar
multiplets spontaneously violating the electric charge conservation. Contrary
to the case of abelian massive electrodynamics, in these theories the
massiveness of photon necessarily implies non-conservation (and also
dequantization) of the electric charge (even in the absence of spontaneous
breakdown of the electromagnetic symmetry). On the other hand, unexpectedly,
there exist models with charge non-conservation where it is possible to keep
the photon mass zero (at least, at the tree level).
| [
{
"created": "Thu, 4 Apr 1996 04:31:32 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Ignatiev",
"A. Yu.",
""
],
[
"Joshi",
"G. C.",
""
]
] | We study a novel type of extensions of the Standard Model which include a hard mass term for the U(1) gauge field and, optionally, the additional scalar multiplets spontaneously violating the electric charge conservation. Contrary to the case of abelian massive electrodynamics, in these theories the massiveness of photon necessarily implies non-conservation (and also dequantization) of the electric charge (even in the absence of spontaneous breakdown of the electromagnetic symmetry). On the other hand, unexpectedly, there exist models with charge non-conservation where it is possible to keep the photon mass zero (at least, at the tree level). |
0807.0174 | Tord Riemann | Stefano Actis (RWTH Aachen University), Janusz Gluza (University of
Silesia), Tord Riemann (DESY) | Virtual Hadronic Corrections to Massive Bhabha Scattering | 7 pages, 4 tables, 3 figures, contribution to proceedings of LL2008,
to appear in NPB(PS) | Nucl.Phys.Proc.Suppl.183:174-180,2008 | 10.1016/j.nuclphysbps.2008.09.100 | DESY 08-084, PITHA-08/14 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Virtual hadronic contributions to the Bhabha process at the NNLO level are
discussed. They are substantial for predictions with per mil accuracy. The
studies of heavy fermion and hadron corrections complete the calculation of
Bhabha virtual effects at the NNLO level.
| [
{
"created": "Tue, 1 Jul 2008 14:54:47 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Actis",
"Stefano",
"",
"RWTH Aachen University"
],
[
"Gluza",
"Janusz",
"",
"University of\n Silesia"
],
[
"Riemann",
"Tord",
"",
"DESY"
]
] | Virtual hadronic contributions to the Bhabha process at the NNLO level are discussed. They are substantial for predictions with per mil accuracy. The studies of heavy fermion and hadron corrections complete the calculation of Bhabha virtual effects at the NNLO level. |
1101.0835 | Muhammad Adeel Ajaib | Muhammad Adeel Ajaib, Ilia Gogoladze, Qaisar Shafi | Muons from Neutralino Annihilations in the Sun: Flipped SU(5) | 13 pages, 11 figures, 1 table | Phys.Rev.D83:075017,2011 | 10.1103/PhysRevD.83.075017 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider two classes of supersymmetric flipped SU(5) models with gravity
mediated supersymmetry breaking such that the thermal neutralino relic
abundance provides the observed dark matter density in the universe. We
estimate the muon flux induced by neutrinos that arise from neutralino
annihilations in the Sun and discuss prospects for detecting this flux in the
IceCube/Deep Core experiment. We also provide comparisons with the
corresponding fluxes in the constrained minimal supersymmetric standard model
and non-universal Higgs models. Regions in the parameter space that can be
explored by the IceCube/DeepCore experiment are identified.
| [
{
"created": "Tue, 4 Jan 2011 22:01:47 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Apr 2011 21:49:24 GMT",
"version": "v2"
}
] | 2011-05-12 | [
[
"Ajaib",
"Muhammad Adeel",
""
],
[
"Gogoladze",
"Ilia",
""
],
[
"Shafi",
"Qaisar",
""
]
] | We consider two classes of supersymmetric flipped SU(5) models with gravity mediated supersymmetry breaking such that the thermal neutralino relic abundance provides the observed dark matter density in the universe. We estimate the muon flux induced by neutrinos that arise from neutralino annihilations in the Sun and discuss prospects for detecting this flux in the IceCube/Deep Core experiment. We also provide comparisons with the corresponding fluxes in the constrained minimal supersymmetric standard model and non-universal Higgs models. Regions in the parameter space that can be explored by the IceCube/DeepCore experiment are identified. |
hep-ph/0512140 | Mauro Anselmino | M. Anselmino | Transversity | 12 pages, 4 figures. Summary of talks delivered at the Workshop
"Hadron Structure and Hadron Spectroscopy", Prague, August 1-3, 2005 and at
the International Workshop on "Transverse Polarisation Phenomena in Hard
Processes" (Transversity 2005), Como, September 7-10, 2005 | null | 10.1142/9789812773272_0002 | null | hep-ph | null | Some general remarks on parton transverse spin distributions and transverse
motions are presented. The issue of accessing experimental information on the
transversity distributions h_1^q is discussed. In particular direct information
could be obtained from Drell-Yan processes with polarized protons and
antiprotons (planned at GSI), while indirect information, coupling h_1^q to the
Collins fragmentation function, is being gathered by HERMES and COMPASS
collaborations. The related issue of transverse Single Spin Asymmetries (SSA)
measured in several processes and the role of the Sivers distribution function
is also discussed.
| [
{
"created": "Mon, 12 Dec 2005 11:13:55 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Anselmino",
"M.",
""
]
] | Some general remarks on parton transverse spin distributions and transverse motions are presented. The issue of accessing experimental information on the transversity distributions h_1^q is discussed. In particular direct information could be obtained from Drell-Yan processes with polarized protons and antiprotons (planned at GSI), while indirect information, coupling h_1^q to the Collins fragmentation function, is being gathered by HERMES and COMPASS collaborations. The related issue of transverse Single Spin Asymmetries (SSA) measured in several processes and the role of the Sivers distribution function is also discussed. |
hep-ph/0312265 | Solveig Skadhauge | M. Hirsch, J. C. Romao, S. Skadhauge, J. W. F. Valle, A. Villanova del
Moral | Phenomenological Tests of Supersymmetric A_4 Family Symmetry Model of
Neutrino Mass | 23 pages, 7 figures | Phys.Rev.D69:093006,2004 | 10.1103/PhysRevD.69.093006 | null | hep-ph | null | Recently Babu, Ma and Valle proposed a model of quark and lepton mixing based
on $A_4$ symmetry. Within this model the lepton and slepton mixings are
intimately related. We perform a numerical study in order to derive the slepton
masses and mixings in agreement with present data from neutrino physics. We
show that, starting from three-fold degeneracy of the neutrino masses at a high
energy scale, a viable low energy neutrino mass matrix can indeed be obtained
in agreement with constraints on lepton flavour violating
$\mu$ and $\tau$ decays. The resulting slepton spectrum must necessarily
include at least one mass below 200 GeV which can be produced at the LHC. The
predictions for the absolute Majorana neutrino mass scale $m_0 \geq 0.3$ eV
ensure that the model will be tested by future cosmological tests and
$\beta\beta_{0\nu}$ searches.
Rates for lepton flavour violating processes
$\ell_j \to \ell_i + \gamma$ in the range of sensitivity of current
experiments are typical in the model, with BR$(\mu \to e \gamma) \gsim
10^{-15}$ and the lower bound BR$(\tau \to \mu \gamma) > 10^{-9}$. To first
approximation, the model leads to maximal leptonic CP violation in neutrino
oscillations.
| [
{
"created": "Thu, 18 Dec 2003 19:26:47 GMT",
"version": "v1"
}
] | 2010-04-06 | [
[
"Hirsch",
"M.",
""
],
[
"Romao",
"J. C.",
""
],
[
"Skadhauge",
"S.",
""
],
[
"Valle",
"J. W. F.",
""
],
[
"del Moral",
"A. Villanova",
""
]
] | Recently Babu, Ma and Valle proposed a model of quark and lepton mixing based on $A_4$ symmetry. Within this model the lepton and slepton mixings are intimately related. We perform a numerical study in order to derive the slepton masses and mixings in agreement with present data from neutrino physics. We show that, starting from three-fold degeneracy of the neutrino masses at a high energy scale, a viable low energy neutrino mass matrix can indeed be obtained in agreement with constraints on lepton flavour violating $\mu$ and $\tau$ decays. The resulting slepton spectrum must necessarily include at least one mass below 200 GeV which can be produced at the LHC. The predictions for the absolute Majorana neutrino mass scale $m_0 \geq 0.3$ eV ensure that the model will be tested by future cosmological tests and $\beta\beta_{0\nu}$ searches. Rates for lepton flavour violating processes $\ell_j \to \ell_i + \gamma$ in the range of sensitivity of current experiments are typical in the model, with BR$(\mu \to e \gamma) \gsim 10^{-15}$ and the lower bound BR$(\tau \to \mu \gamma) > 10^{-9}$. To first approximation, the model leads to maximal leptonic CP violation in neutrino oscillations. |
1907.13168 | Debashis Saha | Pankaj Agrawal, Debashis Saha, Ambresh Shivaji | Di-vector boson production in association with a Higgs boson at hadron
colliders | Version to appear in PRD. This version includes the results for
polarized final states | Phys. Rev. D 103, 116020 (2021) | 10.1103/PhysRevD.103.116020 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the production of a Higgs boson in association with two
electroweak vector bosons at hadron colliders. In particular, we examine
$\gamma\gamma H$, $\gamma ZH$, $ZZH$, and $W^{+}W^{-}H$ production at the LHC
(14 TeV), HE-LHC (27 TeV), and FCC-hh (100 TeV) colliders. Our main focus is to
estimate the gluon-gluon ($gg$) channel ($gg \to VV^\prime H$) contributions to
$pp \to VV^\prime H~(V,V^\prime=\gamma,Z,W)$ and compare them with
corresponding contributions arising from the quark-quark ($qq$) channel.
Technically, the leading order $gg$ channel contribution to $pp \to VV^\prime
H$ cross section is an NNLO correction in $\alpha_s$. In the processes under
consideration, we find that in the $gg$ channel, $W^{+}W^{-}H$ has the largest
cross section. However, relative contribution of the $gg$ channel is more
important for the $pp \to ZZH$ production. At the FCC-hh, $gg \to ZZH$
contribution is comparable with the NLO QCD correction to $qq \to ZZH$. We also
compute the cross sections when $W$ and $Z$-bosons are polarized. In the
production of $W^{+}W^{-}H$ and $ZZH$, we find that the $gg$ channel
contributes more significantly when the vector bosons are longitudinally
polarized. By examining such events, one can increase the fraction of the $gg$
channel contribution to these processes. Further, we have studied
beyond-the-standard-model effects in the $\kappa$-framework. We find that the
$gg$ channel processes $ZZH$ and $WWH$ have very mild dependence on
$\kappa_\lambda$, but strong dependence on $\kappa_t$ and $\kappa_V$. The $qq$
channel processes mainly depend on $\kappa_V$. Dependence of the $gg$ channel
contribution on $\kappa_V$ is stronger than that of the $qq$ channel
contribution. Therefore focusing on events with longitudinally polarized $W$
and $Z$-bosons, one can find stronger dependence on $\kappa_V$ that can help us
measure this parameter.
| [
{
"created": "Tue, 30 Jul 2019 18:33:12 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Jun 2021 14:30:08 GMT",
"version": "v2"
}
] | 2021-06-30 | [
[
"Agrawal",
"Pankaj",
""
],
[
"Saha",
"Debashis",
""
],
[
"Shivaji",
"Ambresh",
""
]
] | We consider the production of a Higgs boson in association with two electroweak vector bosons at hadron colliders. In particular, we examine $\gamma\gamma H$, $\gamma ZH$, $ZZH$, and $W^{+}W^{-}H$ production at the LHC (14 TeV), HE-LHC (27 TeV), and FCC-hh (100 TeV) colliders. Our main focus is to estimate the gluon-gluon ($gg$) channel ($gg \to VV^\prime H$) contributions to $pp \to VV^\prime H~(V,V^\prime=\gamma,Z,W)$ and compare them with corresponding contributions arising from the quark-quark ($qq$) channel. Technically, the leading order $gg$ channel contribution to $pp \to VV^\prime H$ cross section is an NNLO correction in $\alpha_s$. In the processes under consideration, we find that in the $gg$ channel, $W^{+}W^{-}H$ has the largest cross section. However, relative contribution of the $gg$ channel is more important for the $pp \to ZZH$ production. At the FCC-hh, $gg \to ZZH$ contribution is comparable with the NLO QCD correction to $qq \to ZZH$. We also compute the cross sections when $W$ and $Z$-bosons are polarized. In the production of $W^{+}W^{-}H$ and $ZZH$, we find that the $gg$ channel contributes more significantly when the vector bosons are longitudinally polarized. By examining such events, one can increase the fraction of the $gg$ channel contribution to these processes. Further, we have studied beyond-the-standard-model effects in the $\kappa$-framework. We find that the $gg$ channel processes $ZZH$ and $WWH$ have very mild dependence on $\kappa_\lambda$, but strong dependence on $\kappa_t$ and $\kappa_V$. The $qq$ channel processes mainly depend on $\kappa_V$. Dependence of the $gg$ channel contribution on $\kappa_V$ is stronger than that of the $qq$ channel contribution. Therefore focusing on events with longitudinally polarized $W$ and $Z$-bosons, one can find stronger dependence on $\kappa_V$ that can help us measure this parameter. |
0804.0350 | Giovanni Ossola | T. Binoth, G. Ossola, C. G. Papadopoulos, and R. Pittau | NLO QCD corrections to tri-boson production | null | JHEP 0806:082,2008 | 10.1088/1126-6708/2008/06/082 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a calculation of the NLO QCD corrections for the production of
three vector bosons at the LHC, namely Z Z Z, W+ W- Z, W+ Z Z, and W+ W- W+
production. The virtual corrections are computed using the recently proposed
method of reduction at the integrand level (OPP reduction). Concerning the
contributions coming from real emission we used the dipole subtraction to treat
the soft and collinear divergences. We find that the QCD corrections for these
electroweak processes are in the range between 70 and 100 percent. As such they
have to be considered in experimental studies of triple vector boson production
at the LHC.
| [
{
"created": "Wed, 2 Apr 2008 13:37:35 GMT",
"version": "v1"
}
] | 2009-01-21 | [
[
"Binoth",
"T.",
""
],
[
"Ossola",
"G.",
""
],
[
"Papadopoulos",
"C. G.",
""
],
[
"Pittau",
"R.",
""
]
] | We present a calculation of the NLO QCD corrections for the production of three vector bosons at the LHC, namely Z Z Z, W+ W- Z, W+ Z Z, and W+ W- W+ production. The virtual corrections are computed using the recently proposed method of reduction at the integrand level (OPP reduction). Concerning the contributions coming from real emission we used the dipole subtraction to treat the soft and collinear divergences. We find that the QCD corrections for these electroweak processes are in the range between 70 and 100 percent. As such they have to be considered in experimental studies of triple vector boson production at the LHC. |
2107.11751 | Hanzhong Zhang | Ao Luo, Ya-Xian Mao, Guang-You Qin, En-Ke Wang and Han-Zhong Zhang | Jet shape and redistribution of the lost energy from jets in Pb+Pb
collisions at the LHC in a multiphase transport model | 10 pages, 9 figures | null | 10.1140/epjc/s10052-022-10110-9 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Jet-medium interaction involves two important effects: jet energy loss and
medium response. The search for jet-induced medium excitations is one of the
hot topics in jet quenching study in relativistic nuclear collisions. In this
work, we perform a systematic study on how the lost energy from hard jets
evolves with the bulk medium and redistributes in the final state of heavy-ion
collisions via a multi-phase transport model. In particular, the ($\Delta \eta,
\Delta \phi$) distribution of charged particles with respect to the jet axis
and jet shape function are studied for various Pb+Pb collision centralities and
for different transverse momentum intervals of charged particles. Our numerical
result shows a strong enhancement of soft particles at large angles for Pb+Pb
collisions relative to p+p collisions at the LHC, qualitatively consistent with
recent CMS data. This indicates that a significant fraction of the lost energy
from hard jets is carried by soft particles at large angles away from the jet
axis.
| [
{
"created": "Sun, 25 Jul 2021 08:10:41 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Jan 2022 01:39:45 GMT",
"version": "v2"
}
] | 2022-03-09 | [
[
"Luo",
"Ao",
""
],
[
"Mao",
"Ya-Xian",
""
],
[
"Qin",
"Guang-You",
""
],
[
"Wang",
"En-Ke",
""
],
[
"Zhang",
"Han-Zhong",
""
]
] | Jet-medium interaction involves two important effects: jet energy loss and medium response. The search for jet-induced medium excitations is one of the hot topics in jet quenching study in relativistic nuclear collisions. In this work, we perform a systematic study on how the lost energy from hard jets evolves with the bulk medium and redistributes in the final state of heavy-ion collisions via a multi-phase transport model. In particular, the ($\Delta \eta, \Delta \phi$) distribution of charged particles with respect to the jet axis and jet shape function are studied for various Pb+Pb collision centralities and for different transverse momentum intervals of charged particles. Our numerical result shows a strong enhancement of soft particles at large angles for Pb+Pb collisions relative to p+p collisions at the LHC, qualitatively consistent with recent CMS data. This indicates that a significant fraction of the lost energy from hard jets is carried by soft particles at large angles away from the jet axis. |
1010.1759 | Gavin Salam | Matteo Cacciari, Juan Rojo, Gavin P. Salam, Gregory Soyez | Jet Reconstruction in Heavy Ion Collisions | 31 pages, 17 figures | Eur.Phys.J.C71:1539,2011 | 10.1140/epjc/s10052-011-1539-z | CERN-PH-TH/2010-223 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the problem of jet reconstruction at heavy-ion colliders using
jet-area-based background subtraction tools as provided by FastJet. We use
Monte Carlo simulations with and without quenching to study the performance of
several jet algorithms, including the option of filtering, under conditions
corresponding to RHIC and LHC collisions. We find that most standard algorithms
perform well, though the anti-kt and filtered Cambridge/Aachen algorithms have
clear advantages in terms of the reconstructed transverse-momentum offset and
dispersion.
| [
{
"created": "Fri, 8 Oct 2010 18:38:59 GMT",
"version": "v1"
}
] | 2011-02-11 | [
[
"Cacciari",
"Matteo",
""
],
[
"Rojo",
"Juan",
""
],
[
"Salam",
"Gavin P.",
""
],
[
"Soyez",
"Gregory",
""
]
] | We examine the problem of jet reconstruction at heavy-ion colliders using jet-area-based background subtraction tools as provided by FastJet. We use Monte Carlo simulations with and without quenching to study the performance of several jet algorithms, including the option of filtering, under conditions corresponding to RHIC and LHC collisions. We find that most standard algorithms perform well, though the anti-kt and filtered Cambridge/Aachen algorithms have clear advantages in terms of the reconstructed transverse-momentum offset and dispersion. |
1208.0498 | Gilberto Colangelo | Gilberto Colangelo, Massimiliano Procura, Lorena Rothen, Ramon Stucki,
Jaume Tarrus | On the factorization of chiral logarithms in the pion form factors | 20 pages, 4 figures. A few misprints corrected and references added,
version appeared in JHEP | JHEP 1209 (2012) 081 | 10.1007/JHEP09(2012)081 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recently proposed hard-pion chiral perturbation theory predicts that the
leading chiral logarithms factorize with respect to the energy dependence in
the chiral limit. This claim has been successfully tested in the pion form
factors up to two loops in chiral perturbation theory. In the present paper we
explain this factorization property at two loops and even show that it is valid
to all orders for a subclass of diagrams. We also demonstrate that
factorization is violated starting at three loops.
| [
{
"created": "Thu, 2 Aug 2012 14:22:48 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Oct 2012 12:42:59 GMT",
"version": "v2"
}
] | 2012-10-25 | [
[
"Colangelo",
"Gilberto",
""
],
[
"Procura",
"Massimiliano",
""
],
[
"Rothen",
"Lorena",
""
],
[
"Stucki",
"Ramon",
""
],
[
"Tarrus",
"Jaume",
""
]
] | The recently proposed hard-pion chiral perturbation theory predicts that the leading chiral logarithms factorize with respect to the energy dependence in the chiral limit. This claim has been successfully tested in the pion form factors up to two loops in chiral perturbation theory. In the present paper we explain this factorization property at two loops and even show that it is valid to all orders for a subclass of diagrams. We also demonstrate that factorization is violated starting at three loops. |
2009.13399 | Sumana Bhattacharyya | Sumana Bhattacharyya, Amaresh Jaiswal and Sutanu Roy | Chemical freeze-out systematics of thermal model analysis using hadron
yield ratios | 11 pages, 6 figures | Phys. Rev. C 103, 024905 (2021) | 10.1103/PhysRevC.103.024905 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We provide a framework to estimate the systematic uncertainties in chemical
freeze-out parameters extracted from $\chi^2$ analysis of thermal model, using
hadron multiplicity ratios in relativistic heavy-ion collision experiments.
Using a well known technique of graph theory, we construct all possible sets of
independent ratios from available hadron yields and perform $\chi^2$
minimization on each set. We show that even for ten hadron yields, one obtains
a large number ($10^8$) of independent sets which results in a distribution of
extracted freeze-out parameters. We analyze these distributions and compare our
results for chemical freeze-out parameters and associated systematic
uncertainties with previous results available in the literature.
| [
{
"created": "Mon, 28 Sep 2020 15:19:28 GMT",
"version": "v1"
},
{
"created": "Sat, 6 Feb 2021 06:11:24 GMT",
"version": "v2"
}
] | 2021-02-10 | [
[
"Bhattacharyya",
"Sumana",
""
],
[
"Jaiswal",
"Amaresh",
""
],
[
"Roy",
"Sutanu",
""
]
] | We provide a framework to estimate the systematic uncertainties in chemical freeze-out parameters extracted from $\chi^2$ analysis of thermal model, using hadron multiplicity ratios in relativistic heavy-ion collision experiments. Using a well known technique of graph theory, we construct all possible sets of independent ratios from available hadron yields and perform $\chi^2$ minimization on each set. We show that even for ten hadron yields, one obtains a large number ($10^8$) of independent sets which results in a distribution of extracted freeze-out parameters. We analyze these distributions and compare our results for chemical freeze-out parameters and associated systematic uncertainties with previous results available in the literature. |
hep-ph/0410169 | Asko Jokinen | Rouzbeh Allahverdi, Asko Jokinen and Anupam Mazumdar | Gravitino production from reheating in split supersymmetry | 5 pages, RevTeX4, typos corrected, references added | Phys.Rev. D71 (2005) 043505 | 10.1103/PhysRevD.71.043505 | NORDITA-2004-80 | hep-ph astro-ph hep-th | null | We discuss gravitino production from reheating in models where the splitting
between particle and sparticle masses can be larger than TeV, as naturally
arising in the context of split supersymmetry. We show that such a production
typically dominates over thermal contributions arising from the interactions of
gauginos, squarks and sleptons. We constrain the supersymmetry breaking scale
of the relevant sector for a given reheat temperature. However the situation
changes when the gravitinos dominate the Universe and decay before
nucleosynthesis. We briefly describe prospects for a successful baryogenesis
and a viable neutralino dark matter in this case.
| [
{
"created": "Tue, 12 Oct 2004 16:13:38 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Oct 2004 12:31:34 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Allahverdi",
"Rouzbeh",
""
],
[
"Jokinen",
"Asko",
""
],
[
"Mazumdar",
"Anupam",
""
]
] | We discuss gravitino production from reheating in models where the splitting between particle and sparticle masses can be larger than TeV, as naturally arising in the context of split supersymmetry. We show that such a production typically dominates over thermal contributions arising from the interactions of gauginos, squarks and sleptons. We constrain the supersymmetry breaking scale of the relevant sector for a given reheat temperature. However the situation changes when the gravitinos dominate the Universe and decay before nucleosynthesis. We briefly describe prospects for a successful baryogenesis and a viable neutralino dark matter in this case. |
hep-ph/0608286 | Ian Low | Ian Low | Measuring the Shape of the Extra Dimension | 15 pages. v2: added discussions singling out the massless zero mode
in Neumann BCs | JHEP0610:054,2006 | 10.1088/1126-6708/2006/10/054 | null | hep-ph hep-th | null | We study the possibility of extracting geometric information on the shape of
the extra dimension from four-dimensional data such as the mass of the
Kaluza-Klein (KK) mode. Assuming one compact extra dimension whose geometry can
be considered as perturbations in the flat background, we show that if there is
a Z2 symmetry in the extra dimension, for example the KK parity in models with
Universal Extra Dimensions, then the warp factor in the metric is completely
determined by the KK mass alone. Without KK parity, additional information
depending on the boundary conditions is needed to fully reconstruct the metric,
even though such information may be experimentally challenging to obtain. The
case in a general background geometry is also considered.
| [
{
"created": "Sun, 27 Aug 2006 19:57:09 GMT",
"version": "v1"
},
{
"created": "Sun, 3 Sep 2006 19:34:01 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Low",
"Ian",
""
]
] | We study the possibility of extracting geometric information on the shape of the extra dimension from four-dimensional data such as the mass of the Kaluza-Klein (KK) mode. Assuming one compact extra dimension whose geometry can be considered as perturbations in the flat background, we show that if there is a Z2 symmetry in the extra dimension, for example the KK parity in models with Universal Extra Dimensions, then the warp factor in the metric is completely determined by the KK mass alone. Without KK parity, additional information depending on the boundary conditions is needed to fully reconstruct the metric, even though such information may be experimentally challenging to obtain. The case in a general background geometry is also considered. |
hep-ph/9809284 | Hai-Yang Cheng | Hai-Yang Cheng | Nonfactorizable Effects in Charmless B Decays and B Meson Lifetimes | 5 pages, 2 figures, talk presented at the XXIX International
Conference on High Energy Physics, Vancouver, July 23-28, 1998 | null | null | null | hep-ph hep-ex | null | Status of nonfactorizable effects in hadronic charmless B decays is reviewed.
Implications of new CLEO measurements on $B^0\to\pi^+\pi^-$ and $B\to\eta' K$
are discussed. Nonfactorizable effects due to color ocet 4-quark operators are
calculated using renormalization group improved QCD sum rules. The resultant
B-meson lifetime ratio $\tau(B^-)/\tau(B_d)$ agrees with experiment.
| [
{
"created": "Mon, 7 Sep 1998 06:58:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Cheng",
"Hai-Yang",
""
]
] | Status of nonfactorizable effects in hadronic charmless B decays is reviewed. Implications of new CLEO measurements on $B^0\to\pi^+\pi^-$ and $B\to\eta' K$ are discussed. Nonfactorizable effects due to color ocet 4-quark operators are calculated using renormalization group improved QCD sum rules. The resultant B-meson lifetime ratio $\tau(B^-)/\tau(B_d)$ agrees with experiment. |
1901.05823 | Fu-Hu Liu | Li-Na Gao, Fu-Hu Liu, Bao-Chun Li | Rapidity dependent transverse momentum spectra of heavy quarkonia
produced in small collision systems at the LHC | 17 pages, 11 figures. Advances in High Energy Physics, accepted | Advances in High Energy Physics 2019, 6739315 (2019) (17 pages) | 10.1155/2019/6739315 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The rapidity dependent transverse momentum spectra of heavy quarkonia (J/psi
and Upsilon mesons) produced in small collision systems such as proton-proton
(pp) and proton-lead (p-Pb) collisions at center-of-mass energy (per nucleon
pair) 5-13 TeV are described by a two-component statistical model which is
based on the Tsallis statistics and inverse power-law. The experimental data
measured by the LHCb Collaboration at the Large Hadron Collider (LHC) are well
fitted by the model results. The related parameters are obtained and the
dependences of parameters on rapidity are analyzed.
| [
{
"created": "Thu, 17 Jan 2019 15:00:46 GMT",
"version": "v1"
},
{
"created": "Sun, 5 May 2019 10:31:04 GMT",
"version": "v2"
}
] | 2019-05-27 | [
[
"Gao",
"Li-Na",
""
],
[
"Liu",
"Fu-Hu",
""
],
[
"Li",
"Bao-Chun",
""
]
] | The rapidity dependent transverse momentum spectra of heavy quarkonia (J/psi and Upsilon mesons) produced in small collision systems such as proton-proton (pp) and proton-lead (p-Pb) collisions at center-of-mass energy (per nucleon pair) 5-13 TeV are described by a two-component statistical model which is based on the Tsallis statistics and inverse power-law. The experimental data measured by the LHCb Collaboration at the Large Hadron Collider (LHC) are well fitted by the model results. The related parameters are obtained and the dependences of parameters on rapidity are analyzed. |
0903.2529 | Xiang Liu | Xiang Liu and Shi-Lin Zhu | Y(4143) is probably a molecular partner of Y(3930) | 6 pages, 1 table, 4 figures | Phys.Rev.D80:017502,2009;Phys.Rev.D.85:019902,2012 | 10.1103/PhysRevD.80.017502 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | After discussing the various possible interpretations of the Y(4143) signal
observed by the CDF collaboration in the $J/\psi \phi$ mode, we tend to
conclude that Y(4143) is probably a $D_s^\ast {\bar D}_s^\ast$ molecular state
with $J^{PC}=0^{++}$ or $2^{++}$ while Y(3930) is its $D^\ast {\bar D}^\ast$
molecular partner as predicted in our previous work (arXiv:0808.0073). Both the
hidden-charm and open charm two-body decays occur through the rescattering of
the vector components within the molecular states while the three- and
four-body open charm decay modes are forbidden kinematically. Hence their
widths are narrow naturally. CDF, Babar and Belle collaborations may have
discovered heavy molecular states already. We urge experimentalists to measure
their quantum numbers and explore their radiative decay modes in the future.
| [
{
"created": "Sat, 14 Mar 2009 10:21:32 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Mar 2009 04:51:12 GMT",
"version": "v2"
}
] | 2012-02-06 | [
[
"Liu",
"Xiang",
""
],
[
"Zhu",
"Shi-Lin",
""
]
] | After discussing the various possible interpretations of the Y(4143) signal observed by the CDF collaboration in the $J/\psi \phi$ mode, we tend to conclude that Y(4143) is probably a $D_s^\ast {\bar D}_s^\ast$ molecular state with $J^{PC}=0^{++}$ or $2^{++}$ while Y(3930) is its $D^\ast {\bar D}^\ast$ molecular partner as predicted in our previous work (arXiv:0808.0073). Both the hidden-charm and open charm two-body decays occur through the rescattering of the vector components within the molecular states while the three- and four-body open charm decay modes are forbidden kinematically. Hence their widths are narrow naturally. CDF, Babar and Belle collaborations may have discovered heavy molecular states already. We urge experimentalists to measure their quantum numbers and explore their radiative decay modes in the future. |
hep-ph/0611361 | Alexey A. Petrov | Alexey A Petrov | Charm mixing in the Standard Model and beyond | 8 pages, 2 figures, Invited talk at International Workshop on
Tau-Charm Physics (Charm 2006), Beijing, China, 5-7 Jun 2006 | Int.J.Mod.Phys.A21:5686-5693,2006 | 10.1142/S0217751X06034902 | WSU-HEP-0602 | hep-ph | null | The motivation most often cited in searches for D0-anti-D0 mixing and
CP-violation in charm system lies with the possibility of observing a signal
from New Physics which dominates that from the Standard Model. We review recent
theoretical predictions and experimental constraints on D0-anti-D0 mixing
parameters, concentrating on possible effects of New Physics.
| [
{
"created": "Wed, 29 Nov 2006 05:44:15 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Petrov",
"Alexey A",
""
]
] | The motivation most often cited in searches for D0-anti-D0 mixing and CP-violation in charm system lies with the possibility of observing a signal from New Physics which dominates that from the Standard Model. We review recent theoretical predictions and experimental constraints on D0-anti-D0 mixing parameters, concentrating on possible effects of New Physics. |
2010.01140 | Xiaojun Yao | Jorge Casalderrey-Solana, Jos\'e Guilherme Milhano, Daniel Pablos,
Krishna Rajagopal, Xiaojun Yao | Jet Wake from Linearized Hydrodynamics | 59 pages, 14 figures; v2: minor change, published version | JHEP05(2021)230 | 10.1007/JHEP05(2021)230 | MIT-CTP/5246 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore how to improve the hybrid model description of the particles
originating from the wake that a jet produced in a heavy ion collision leaves
in the droplet of quark-gluon plasma (QGP) through which it propagates, using
linearized hydrodynamics on a background Bjorken flow. Jet energy and momentum
loss described by the hybrid model become currents sourcing linearized
hydrodynamics. By solving the linearized hydrodynamic equations numerically, we
investigate the development of the wake in the dynamically evolving droplet of
QGP, study the effect of viscosity, scrutinize energy-momentum conservation,
and check the validity of the linear approximation. We find that linearized
hydrodynamics works better in the viscous case because diffusive modes damp the
energy-momentum perturbation produced by the jet. We calculate the distribution
of particles produced from the jet wake by using the Cooper-Frye prescription
and find that both the transverse momentum spectrum and the distribution of
particles in azimuthal angle are similar in shape in linearized hydrodynamics
and in the hybrid model. Their normalizations are different because the
momentum-rapidity distribution in the linearized hydrodynamics analysis is more
spread out, due to sound modes. Since the Bjorken flow has no transverse
expansion, we explore the effect of transverse flow by using local boosts to
add it into the Cooper-Frye formula. After including the effects of transverse
flow in this way, the transverse momentum spectrum becomes harder: more
particles with transverse momenta bigger than $2$ GeV are produced than in the
hybrid model. Although we defer implementing this analysis in a jet Monte
Carlo, as would be needed to make quantitative comparisons to data, we gain a
qualitative sense of how the jet wake may modify jet observables by computing
proxies for two example observables: the lost energy recovered in a cone of
varying open angle, and the fragmentation function. We find that linearized
hydrodynamics with transverse flow effects added improves the description of
the jet wake in the hybrid model in just the way that comparison to data
indicates is needed. Our study illuminates a path to improving the description
of the wake in the hybrid model, highlighting the need to take into account the
effects of both transverse flow and the broadening of the energy-momentum
perturbation in spacetime rapidity on particle production.
| [
{
"created": "Fri, 2 Oct 2020 18:00:05 GMT",
"version": "v1"
},
{
"created": "Mon, 31 May 2021 14:00:36 GMT",
"version": "v2"
}
] | 2021-06-01 | [
[
"Casalderrey-Solana",
"Jorge",
""
],
[
"Milhano",
"José Guilherme",
""
],
[
"Pablos",
"Daniel",
""
],
[
"Rajagopal",
"Krishna",
""
],
[
"Yao",
"Xiaojun",
""
]
] | We explore how to improve the hybrid model description of the particles originating from the wake that a jet produced in a heavy ion collision leaves in the droplet of quark-gluon plasma (QGP) through which it propagates, using linearized hydrodynamics on a background Bjorken flow. Jet energy and momentum loss described by the hybrid model become currents sourcing linearized hydrodynamics. By solving the linearized hydrodynamic equations numerically, we investigate the development of the wake in the dynamically evolving droplet of QGP, study the effect of viscosity, scrutinize energy-momentum conservation, and check the validity of the linear approximation. We find that linearized hydrodynamics works better in the viscous case because diffusive modes damp the energy-momentum perturbation produced by the jet. We calculate the distribution of particles produced from the jet wake by using the Cooper-Frye prescription and find that both the transverse momentum spectrum and the distribution of particles in azimuthal angle are similar in shape in linearized hydrodynamics and in the hybrid model. Their normalizations are different because the momentum-rapidity distribution in the linearized hydrodynamics analysis is more spread out, due to sound modes. Since the Bjorken flow has no transverse expansion, we explore the effect of transverse flow by using local boosts to add it into the Cooper-Frye formula. After including the effects of transverse flow in this way, the transverse momentum spectrum becomes harder: more particles with transverse momenta bigger than $2$ GeV are produced than in the hybrid model. Although we defer implementing this analysis in a jet Monte Carlo, as would be needed to make quantitative comparisons to data, we gain a qualitative sense of how the jet wake may modify jet observables by computing proxies for two example observables: the lost energy recovered in a cone of varying open angle, and the fragmentation function. We find that linearized hydrodynamics with transverse flow effects added improves the description of the jet wake in the hybrid model in just the way that comparison to data indicates is needed. Our study illuminates a path to improving the description of the wake in the hybrid model, highlighting the need to take into account the effects of both transverse flow and the broadening of the energy-momentum perturbation in spacetime rapidity on particle production. |
hep-ph/0612079 | Biswajoy Brahmachari | Biswajoy Brahmachari, Nobuchika Okada | A 3 X 2 texture for neutrino oscillations and leptogenesis | version accepted in Phys. Lett. B | Phys.Lett.B660:508-514,2008 | 10.1016/j.physletb.2008.01.043 | KEK-TH-1117, VEC/PHYSICS/P/1/2006-2007 | hep-ph | null | In an economical system with only two heavy right handed neutrinos, we
postulate a new texture for $3 \times 2$ Dirac mass matrix $m_D$. This model
implies one massless light neutrino and thus displays only two patterns of mass
spectrum for light neutrinos, namely hierarchical or inverse-hierarchical. Both
the cases can correctly reproduce all the current neutrino oscillation data
with a unique prediction $m_{\nu_e \nu_e} = \frac{\sqrt{\Delta
m^2_{solar}}}{3}$ and $\sqrt{\Delta m^2_{atm}}$ for the hierarchical and the
inverse-hierarchica cases, respectively, which can be tested in next generation
neutrino-less double beta decay experiments. Introducing a single physical CP
phase in $m_D$, we examine baryon asymmetry through leptogenesis.
Interestingly, through the CP phase there are correlations between the amount
of baryon asymmetry and neutrino oscillation parameters. We find that for a
fixed CP phase, the hierarchical case also succeeds in generating the observed
baryon asymmetry in our universe, plus a non-vanishing $U_{e3}$ which is
accessible in future baseline neutrino oscillation experiments.
| [
{
"created": "Thu, 7 Dec 2006 07:17:24 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Dec 2006 12:19:31 GMT",
"version": "v2"
},
{
"created": "Tue, 5 Feb 2008 10:14:00 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Brahmachari",
"Biswajoy",
""
],
[
"Okada",
"Nobuchika",
""
]
] | In an economical system with only two heavy right handed neutrinos, we postulate a new texture for $3 \times 2$ Dirac mass matrix $m_D$. This model implies one massless light neutrino and thus displays only two patterns of mass spectrum for light neutrinos, namely hierarchical or inverse-hierarchical. Both the cases can correctly reproduce all the current neutrino oscillation data with a unique prediction $m_{\nu_e \nu_e} = \frac{\sqrt{\Delta m^2_{solar}}}{3}$ and $\sqrt{\Delta m^2_{atm}}$ for the hierarchical and the inverse-hierarchica cases, respectively, which can be tested in next generation neutrino-less double beta decay experiments. Introducing a single physical CP phase in $m_D$, we examine baryon asymmetry through leptogenesis. Interestingly, through the CP phase there are correlations between the amount of baryon asymmetry and neutrino oscillation parameters. We find that for a fixed CP phase, the hierarchical case also succeeds in generating the observed baryon asymmetry in our universe, plus a non-vanishing $U_{e3}$ which is accessible in future baseline neutrino oscillation experiments. |
2006.11264 | Bartosz Fornal | Bartosz Fornal, Pearl Sandick, Jing Shu, Meng Su, Yue Zhao | Boosted Dark Matter Interpretation of the XENON1T Excess | 5 pages, 2 figures; v2: Extended discussion of the predicted daily
modulation of the signal | Phys. Rev. Lett. 125, 161804 (2020) | 10.1103/PhysRevLett.125.161804 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose boosted dark matter (BDM) as a possible explanation for the excess
of keV electron recoil events observed by XENON1T. BDM particles have
velocities much larger than those typical of virialized dark matter, and, as
such, BDM-electron scattering can naturally produce keV electron recoils. We
show that the required BDM-electron scattering cross sections can be easily
realized in a simple model with a heavy vector mediator. Though these cross
sections are too large for BDM to escape from the Sun, the BDM flux can
originate from the Galactic Center or from halo dark matter annihilations.
Furthermore, a daily modulation of the BDM signal will be present, which could
not only be used to differentiate it from various backgrounds, but would also
provide important directional information for the BDM flux.
| [
{
"created": "Fri, 19 Jun 2020 17:51:37 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Jun 2020 07:59:02 GMT",
"version": "v2"
}
] | 2020-10-15 | [
[
"Fornal",
"Bartosz",
""
],
[
"Sandick",
"Pearl",
""
],
[
"Shu",
"Jing",
""
],
[
"Su",
"Meng",
""
],
[
"Zhao",
"Yue",
""
]
] | We propose boosted dark matter (BDM) as a possible explanation for the excess of keV electron recoil events observed by XENON1T. BDM particles have velocities much larger than those typical of virialized dark matter, and, as such, BDM-electron scattering can naturally produce keV electron recoils. We show that the required BDM-electron scattering cross sections can be easily realized in a simple model with a heavy vector mediator. Though these cross sections are too large for BDM to escape from the Sun, the BDM flux can originate from the Galactic Center or from halo dark matter annihilations. Furthermore, a daily modulation of the BDM signal will be present, which could not only be used to differentiate it from various backgrounds, but would also provide important directional information for the BDM flux. |
1210.7804 | Amol Upadhye | Amol Upadhye | Symmetron dark energy in laboratory experiments | 4 pages, 2 figures. Matches version accepted by PRL | null | 10.1103/PhysRevLett.110.031301 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The symmetron scalar field is a matter-coupled dark energy candidate which
effectively decouples from matter in high-density regions through a symmetry
restoration. We consider a previously unexplored regime, in which the vacuum
mass $\mu \sim 2.4\times 10^{-3}$ eV of the symmetron is near the dark energy
scale, and the matter coupling parameter $M \sim 1$ TeV is just beyond Standard
Model energies. Such a field will give rise to a fifth force at submillimeter
distances which can be probed by short-range gravity experiments. We show that
a torsion pendulum experiment such as E\"ot-Wash can exclude symmetrons in this
regime for all self-couplings $\lambda \lesssim 7.5$.
| [
{
"created": "Mon, 29 Oct 2012 20:00:02 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Jan 2013 02:19:53 GMT",
"version": "v2"
}
] | 2013-05-30 | [
[
"Upadhye",
"Amol",
""
]
] | The symmetron scalar field is a matter-coupled dark energy candidate which effectively decouples from matter in high-density regions through a symmetry restoration. We consider a previously unexplored regime, in which the vacuum mass $\mu \sim 2.4\times 10^{-3}$ eV of the symmetron is near the dark energy scale, and the matter coupling parameter $M \sim 1$ TeV is just beyond Standard Model energies. Such a field will give rise to a fifth force at submillimeter distances which can be probed by short-range gravity experiments. We show that a torsion pendulum experiment such as E\"ot-Wash can exclude symmetrons in this regime for all self-couplings $\lambda \lesssim 7.5$. |
0910.3073 | Nick Evans | Raul Alvares, Nick Evans, Astrid Gebauer, George James Weatherill | Holographic integral equations and walking technicolour | 17 pages, 4 Figures, small added analysis | Phys.Rev.D81:025013,2010 | 10.1103/PhysRevD.81.025013 | SHEP-09-27 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study chiral symmetry breaking in the holographic D3-D7 system in a simple
model with an arbitrary running coupling. We derive equations for the D7
embedding and show there is a light pion. In particular we present simple
integral equations, involving just the running coupling and the quark self
energy, for the quark condensate and the pion decay constant. We compare these
to the Pagels-Stokar or constituent quark model equivalent. We discuss the
implications for walking Technicolour theories. We also perform a similar
analysis in the four dimensional field theory whose dual is the
non-supersymmetric D3-D5 system and propose that it represents a walking theory
in which the quark condensate has dimension 2 + sqrt{3}.
| [
{
"created": "Fri, 16 Oct 2009 10:25:14 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Nov 2009 09:52:41 GMT",
"version": "v2"
}
] | 2010-03-12 | [
[
"Alvares",
"Raul",
""
],
[
"Evans",
"Nick",
""
],
[
"Gebauer",
"Astrid",
""
],
[
"Weatherill",
"George James",
""
]
] | We study chiral symmetry breaking in the holographic D3-D7 system in a simple model with an arbitrary running coupling. We derive equations for the D7 embedding and show there is a light pion. In particular we present simple integral equations, involving just the running coupling and the quark self energy, for the quark condensate and the pion decay constant. We compare these to the Pagels-Stokar or constituent quark model equivalent. We discuss the implications for walking Technicolour theories. We also perform a similar analysis in the four dimensional field theory whose dual is the non-supersymmetric D3-D5 system and propose that it represents a walking theory in which the quark condensate has dimension 2 + sqrt{3}. |
1909.02044 | Matthew Sullivan | Hooman Davoudiasl, Ian M. Lewis, Matthew Sullivan | Higgs Troika for Baryon Asymmetry | 11 pages, 2 figures. Extended discussion of reheating mechanism,
minor revisions | Phys. Rev. D 101, 055010 (2020) | 10.1103/PhysRevD.101.055010 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | To explain the baryon asymmetry of the Universe, we extend the Standard Model
(SM) with two additional Higgs doublets with small vacuum expectation values.
The additional Higgs fields interact with SM fermions through complex Yukawa
couplings, leading to new sources of CP violation. We propose a simple flavor
model with $\mathcal{O}(1)$ or less Yukawa couplings for quarks and charged
leptons, consistent with current flavor constraints. To generate neutrino
masses and the baryon asymmetry, right-handed neutrinos in the $\sim 0.1-10$
TeV range couple to the "Higgs Troika." The new Higgs doublet masses could be
near the TeV scale, allowing for asymmetric decays into Standard Model lepton
doublets and right-handed neutrinos. The asymmetry in lepton doublets is then
processed into a baryon asymmetry, similar to leptogenesis. Since the masses of
the new fields are near the TeV scale, there is potentially a rich high energy
collider phenomenology, including observable deviations in the 125 GeV Higgs
decay into muons and taus, as well as detectable low energy signals such as the
electron EDM or $\mu\rightarrow e\gamma$. Hence, this is in principle a
testable model for generation of baryon asymmetry, similar in that respect to
"electroweak baryogenesis."
| [
{
"created": "Wed, 4 Sep 2019 18:38:42 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Mar 2020 18:00:10 GMT",
"version": "v2"
}
] | 2020-03-26 | [
[
"Davoudiasl",
"Hooman",
""
],
[
"Lewis",
"Ian M.",
""
],
[
"Sullivan",
"Matthew",
""
]
] | To explain the baryon asymmetry of the Universe, we extend the Standard Model (SM) with two additional Higgs doublets with small vacuum expectation values. The additional Higgs fields interact with SM fermions through complex Yukawa couplings, leading to new sources of CP violation. We propose a simple flavor model with $\mathcal{O}(1)$ or less Yukawa couplings for quarks and charged leptons, consistent with current flavor constraints. To generate neutrino masses and the baryon asymmetry, right-handed neutrinos in the $\sim 0.1-10$ TeV range couple to the "Higgs Troika." The new Higgs doublet masses could be near the TeV scale, allowing for asymmetric decays into Standard Model lepton doublets and right-handed neutrinos. The asymmetry in lepton doublets is then processed into a baryon asymmetry, similar to leptogenesis. Since the masses of the new fields are near the TeV scale, there is potentially a rich high energy collider phenomenology, including observable deviations in the 125 GeV Higgs decay into muons and taus, as well as detectable low energy signals such as the electron EDM or $\mu\rightarrow e\gamma$. Hence, this is in principle a testable model for generation of baryon asymmetry, similar in that respect to "electroweak baryogenesis." |
hep-ph/9907443 | Chi-Sing Lam | C.S. Lam | Small-Recoil Approximation | 21 pages with 4 figures | Int.J.Mod.Phys. A14 (1999) 3435-3450 | 10.1142/S0217751X99001597 | null | hep-ph | null | In this review we discuss a technique to compute and to sum a class of
Feynman diagrams, and some of its applications. These are diagrams containing
one or more energetic particles that suffer very little recoil in their
interactions. When recoil is completely neglected, a decomposition formula can
be proven. This formula is a generalization of the well-known eikonal formula,
to non-abelian interactions. It expresses the amplitude as a sum of products of
irreducible amplitudes, with each irreducible amplitude being the amplitude to
emit one, or several mutually interacting, quasi-particles. For abelian
interaction a quasi-particle is nothing but the original boson, so this
decomposition formula reduces to the eikonal formula. In non-abelian situations
each quasi-particle can be made up of many bosons, though always with a total
quantum number identical to that of a single boson. This decomposition enables
certain amplitudes of all orders to be summed up into an exponential form, and
it allows subleading contributions of a certain kind, which is difficult to
reach in the usual way, to be computed. For bosonic emissions from a heavy
source with many constituents, a quasi-particle amplitude turns out to be an
amplitude in which all bosons are emitted from the same constituent. For
high-energy parton-parton scattering in the near-forward direction, the
quasi-particle turns out to be the Reggeon, and this formalism shows clearly
why gluons reggeize but photons do not. The ablility to compute subleading
terms in this formalism allows the BFKL-Pomeron amplitude to be extrapolated to
asymptotic energies, in a unitary way preserving the Froissart bound. We also
consider recoil corrections for abelian interactions in order to accommodate
the Landau-Pomeranchuk-Migdal effect.
| [
{
"created": "Wed, 21 Jul 1999 14:10:29 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Lam",
"C. S.",
""
]
] | In this review we discuss a technique to compute and to sum a class of Feynman diagrams, and some of its applications. These are diagrams containing one or more energetic particles that suffer very little recoil in their interactions. When recoil is completely neglected, a decomposition formula can be proven. This formula is a generalization of the well-known eikonal formula, to non-abelian interactions. It expresses the amplitude as a sum of products of irreducible amplitudes, with each irreducible amplitude being the amplitude to emit one, or several mutually interacting, quasi-particles. For abelian interaction a quasi-particle is nothing but the original boson, so this decomposition formula reduces to the eikonal formula. In non-abelian situations each quasi-particle can be made up of many bosons, though always with a total quantum number identical to that of a single boson. This decomposition enables certain amplitudes of all orders to be summed up into an exponential form, and it allows subleading contributions of a certain kind, which is difficult to reach in the usual way, to be computed. For bosonic emissions from a heavy source with many constituents, a quasi-particle amplitude turns out to be an amplitude in which all bosons are emitted from the same constituent. For high-energy parton-parton scattering in the near-forward direction, the quasi-particle turns out to be the Reggeon, and this formalism shows clearly why gluons reggeize but photons do not. The ablility to compute subleading terms in this formalism allows the BFKL-Pomeron amplitude to be extrapolated to asymptotic energies, in a unitary way preserving the Froissart bound. We also consider recoil corrections for abelian interactions in order to accommodate the Landau-Pomeranchuk-Migdal effect. |
1905.03792 | Rhorry Gauld | Rhorry Gauld | Precise predictions for multi-${\rm TeV}$ and ${\rm PeV}$ energy
neutrino scattering rates | 7 pages, 5 figures. v2: Matches published version. Additionally
includes coherent scattering results. All numerical results available from
zeondo record: https://zenodo.org/record/3766134 | Phys. Rev. D 100, 091301 (2019) | 10.1103/PhysRevD.100.091301 | NIKHEF 2019-011 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The scattering rate of multi-${\rm TeV}$ and ${\rm PeV}$ energy neutrinos is
fast becoming an interesting topic in (astro)particle-physics. This is due to
experimental progress at Neutrino Telescopes such as IceCube which have begun
to gain sensitivity to the flux of neutrinos in this energy range. In view of
this, a precise calculation of the scattering rate of neutrinos upon atoms is
presented. The two main components of the calculation are the differential
cross-section predictions for neutrino scattering upon an atomic nucleus (such
as that which make up water), as well as upon atomic electrons. In the first
case, the predictions for neutrino-nucleon cross-sections in charged- and
neutral-current scattering are refined by including resonant contributions
generated within the photon field of the nucleus, which alter the considered
distributions by up to $\approx 4\%$. In the latter case, radiative corrections
are provided for all $2\to2$ scattering processes of the form $\bar{\nu}_e
e^-\to f\bar{f}^{\prime}$. For antineutrino energies of
$E_{\bar{\nu}_e}\approx6{\rm~PeV}$, where these processes become resonantly
enhanced (the Glashow resonance) and dominate the total cross-section, these
corrections amount to $\approx-10\%$.
| [
{
"created": "Thu, 9 May 2019 18:00:03 GMT",
"version": "v1"
},
{
"created": "Sat, 25 Apr 2020 21:45:34 GMT",
"version": "v2"
}
] | 2020-04-28 | [
[
"Gauld",
"Rhorry",
""
]
] | The scattering rate of multi-${\rm TeV}$ and ${\rm PeV}$ energy neutrinos is fast becoming an interesting topic in (astro)particle-physics. This is due to experimental progress at Neutrino Telescopes such as IceCube which have begun to gain sensitivity to the flux of neutrinos in this energy range. In view of this, a precise calculation of the scattering rate of neutrinos upon atoms is presented. The two main components of the calculation are the differential cross-section predictions for neutrino scattering upon an atomic nucleus (such as that which make up water), as well as upon atomic electrons. In the first case, the predictions for neutrino-nucleon cross-sections in charged- and neutral-current scattering are refined by including resonant contributions generated within the photon field of the nucleus, which alter the considered distributions by up to $\approx 4\%$. In the latter case, radiative corrections are provided for all $2\to2$ scattering processes of the form $\bar{\nu}_e e^-\to f\bar{f}^{\prime}$. For antineutrino energies of $E_{\bar{\nu}_e}\approx6{\rm~PeV}$, where these processes become resonantly enhanced (the Glashow resonance) and dominate the total cross-section, these corrections amount to $\approx-10\%$. |
hep-ph/0111090 | Rikard Enberg | R. Enberg, G. Ingelman and L. Motyka | Hard colour singlet exchange and gaps between jets at the Tevatron | 15 pages, 11 eps figures | Phys.Lett.B524:273-282,2002 | 10.1016/S0370-2693(01)01379-X | TSL/ISV-2001-0255 | hep-ph | null | The new kind of events with a rapidity gap between two high-E_T jets,
observed in high energy ppbar collisions at the Tevatron, is found to be well
described by the exchange of a colour singlet gluon system in the BFKL
framework. This requires going beyond the conventional asymptotic Mueller-Tang
approximation, which results in qualitatively different features of the basic
parton-parton scattering amplitude. Non-leading corrections to the BFKL
equation are included by incorporation of the consistency constraint and the
running QCD coupling. Hadronisation and other non-perturbative QCD effects are
treated through a complete Monte Carlo simulation, providing a gap survival
probability that varies event-by-event, facilitating comparison with
experimental results.
| [
{
"created": "Thu, 8 Nov 2001 20:37:07 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Enberg",
"R.",
""
],
[
"Ingelman",
"G.",
""
],
[
"Motyka",
"L.",
""
]
] | The new kind of events with a rapidity gap between two high-E_T jets, observed in high energy ppbar collisions at the Tevatron, is found to be well described by the exchange of a colour singlet gluon system in the BFKL framework. This requires going beyond the conventional asymptotic Mueller-Tang approximation, which results in qualitatively different features of the basic parton-parton scattering amplitude. Non-leading corrections to the BFKL equation are included by incorporation of the consistency constraint and the running QCD coupling. Hadronisation and other non-perturbative QCD effects are treated through a complete Monte Carlo simulation, providing a gap survival probability that varies event-by-event, facilitating comparison with experimental results. |
0808.3952 | Farvah Mahmoudi | F. Mahmoudi | Flavor Data Constraints on the SUSY Parameter Space | Invited talk at the 16th International Conference on Supersymmetry
and the Unification of Fundamental Interactions (SUSY08), Seoul, Korea, June
16-21, 2008 | AIP Conf.Proc.1078:243-246,2009 | 10.1063/1.3051922 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an overview of the indirect constraints from flavor physics on
supersymmetric models. During the past few years flavor data, and in particular
b -> s gamma transitions, have been extensively used in order to constrain
supersymmetric parameter spaces. We will briefly illustrate here the
constraints obtained by a collection of low energy observables including FCNC
transitions, rare decays, leptonic and semileptonic decays of B mesons, as well
as leptonic decays of K mesons. The theoretical predictions can be obtained
using the computer program SuperIso.
| [
{
"created": "Thu, 28 Aug 2008 19:41:42 GMT",
"version": "v1"
}
] | 2009-02-02 | [
[
"Mahmoudi",
"F.",
""
]
] | We present an overview of the indirect constraints from flavor physics on supersymmetric models. During the past few years flavor data, and in particular b -> s gamma transitions, have been extensively used in order to constrain supersymmetric parameter spaces. We will briefly illustrate here the constraints obtained by a collection of low energy observables including FCNC transitions, rare decays, leptonic and semileptonic decays of B mesons, as well as leptonic decays of K mesons. The theoretical predictions can be obtained using the computer program SuperIso. |
hep-ph/0005118 | Lee Jae Sik | Eri Asakawa, S.Y. Choi, and Jae Sik Lee | Probing the MSSM Higgs Boson Sector with Explicit CP Violation through
Third Generation Fermion Pair Production at Muon Colliders | 30 pages, 7 figures including 5 eps ones. Typos corrected and
references added. To appear in Phys. Rev. D | Phys.Rev. D63 (2001) 015012 | 10.1103/PhysRevD.63.015012 | KIAS-P00021, OCHA-PP-156 | hep-ph | null | We perform a systematic study of the production of a third-generation
fermion-pair, $\mu^+\mu^-\to f\bar{f}$ for $f=\tau^-,b$, and t in the minimal
supersymmetric standard model (MSSM) with explicit CP violation, which is
induced radiatively by soft trilinear interactions related to squarks of the
third generation. We classify all the observables for probing the CP property
of the Higgs bosons constructed by the initial muon beam polarization along
with the unpolarized final fermions and with the final-fermion polarization
configuration of equal helicity, respectively. The observables allow for
complete determination of CP property of the neutral Higgs bosons. The
interference between the Higgs boson and gauge boson contributions also could
provide a powerful method for the determination of the CP property of two heavy
Higgs bosons in the top-quark pair production near the energy region of the
Higgs-boson resonances. For the lightest Higgs-boson mass there is no sizable
interference between scalar and vector contributions for the determination of
the CP property of the lightest Higgs boson. We give a detailed numerical
analysis to show how the radiatively-induced CP violation in the Higgs sector
of the MSSM can be measured.
| [
{
"created": "Fri, 12 May 2000 03:47:41 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Aug 2000 06:18:10 GMT",
"version": "v2"
},
{
"created": "Thu, 5 Oct 2000 02:50:48 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Asakawa",
"Eri",
""
],
[
"Choi",
"S. Y.",
""
],
[
"Lee",
"Jae Sik",
""
]
] | We perform a systematic study of the production of a third-generation fermion-pair, $\mu^+\mu^-\to f\bar{f}$ for $f=\tau^-,b$, and t in the minimal supersymmetric standard model (MSSM) with explicit CP violation, which is induced radiatively by soft trilinear interactions related to squarks of the third generation. We classify all the observables for probing the CP property of the Higgs bosons constructed by the initial muon beam polarization along with the unpolarized final fermions and with the final-fermion polarization configuration of equal helicity, respectively. The observables allow for complete determination of CP property of the neutral Higgs bosons. The interference between the Higgs boson and gauge boson contributions also could provide a powerful method for the determination of the CP property of two heavy Higgs bosons in the top-quark pair production near the energy region of the Higgs-boson resonances. For the lightest Higgs-boson mass there is no sizable interference between scalar and vector contributions for the determination of the CP property of the lightest Higgs boson. We give a detailed numerical analysis to show how the radiatively-induced CP violation in the Higgs sector of the MSSM can be measured. |
hep-ph/0101263 | Margarete Muhlleitner | M.M. Muhlleitner | Production of MSSM Higgs Bosons at Future $\gamma\gamma$ Colliders | Contributed to 5th International Linear Collider Workshop (LCWS
2000), Fermilab, Batavia, Illinois, 24-28 Oct 2000; 4 pages | null | 10.1063/1.1394328 | PM/01--04 | hep-ph | null | Future $\gamma\gamma$ colliders allow the production of the heavy neutral
MSSM Higgs bosons $H$ and $A$ as single resonances. The prospects of finding
these particles in the $b\bar{b}$ and the neutralino-pair final states have
been analysed. The $H,A$ bosons can be discovered for medium values of
$\tan\beta$ with masses up to 70--80% of the initial $e^\pm e^-$ c.m. energy.
This production mode thus covers parts of the supersymmetric parameter space
that are not accessible at other colliders.
| [
{
"created": "Tue, 23 Jan 2001 17:54:30 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Muhlleitner",
"M. M.",
""
]
] | Future $\gamma\gamma$ colliders allow the production of the heavy neutral MSSM Higgs bosons $H$ and $A$ as single resonances. The prospects of finding these particles in the $b\bar{b}$ and the neutralino-pair final states have been analysed. The $H,A$ bosons can be discovered for medium values of $\tan\beta$ with masses up to 70--80% of the initial $e^\pm e^-$ c.m. energy. This production mode thus covers parts of the supersymmetric parameter space that are not accessible at other colliders. |
1110.4078 | Stephen Mrenna | Stephen Mrenna | A Closer Look at the 2011 cMSSM Results from CMS | null | null | null | FERMILAB-PUB-11-551-CD | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a phenomenological appraisal of the results of several searches
for Supersymmetry (SUSY) performed at the LHC by the CMS collaboration and
interpreted in the context of the cMSSM. Part of the analysis focuses on which
SUSY production processes are being probed. We observe that much of the current
exclusion region is dominated by squark-squark and squark-gluino production,
and explain the shape of the exclusion curves. Based on this analysis and an
estimation of future reach, additional simplified models are suggested. Other
phenomenological details are discussed, such as the effect of radiation on
acceptance.
| [
{
"created": "Tue, 18 Oct 2011 18:33:05 GMT",
"version": "v1"
}
] | 2011-10-19 | [
[
"Mrenna",
"Stephen",
""
]
] | We present a phenomenological appraisal of the results of several searches for Supersymmetry (SUSY) performed at the LHC by the CMS collaboration and interpreted in the context of the cMSSM. Part of the analysis focuses on which SUSY production processes are being probed. We observe that much of the current exclusion region is dominated by squark-squark and squark-gluino production, and explain the shape of the exclusion curves. Based on this analysis and an estimation of future reach, additional simplified models are suggested. Other phenomenological details are discussed, such as the effect of radiation on acceptance. |
0810.2762 | Giulia Zanderighi | R. Keith Ellis, W. T. Giele, Zoltan Kunszt, Kirill Melnikov and Giulia
Zanderighi | One-loop amplitudes for W+3 jet production in hadron collisions | 26 pages, 5 figures, v2 to agree with published version | JHEP 0901:012,2009 | 10.1088/1126-6708/2009/01/012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We employ the recently developed method of generalized $D$-dimensional
unitarity to compute one-loop virtual corrections to all scattering amplitudes
relevant for the production of a $W$ boson in association with three jets in
hadronic collisions, treating all quarks as massless.
| [
{
"created": "Wed, 15 Oct 2008 18:07:33 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Dec 2008 10:48:10 GMT",
"version": "v2"
}
] | 2009-02-12 | [
[
"Ellis",
"R. Keith",
""
],
[
"Giele",
"W. T.",
""
],
[
"Kunszt",
"Zoltan",
""
],
[
"Melnikov",
"Kirill",
""
],
[
"Zanderighi",
"Giulia",
""
]
] | We employ the recently developed method of generalized $D$-dimensional unitarity to compute one-loop virtual corrections to all scattering amplitudes relevant for the production of a $W$ boson in association with three jets in hadronic collisions, treating all quarks as massless. |
hep-ph/0507185 | Per Osland | P. Osland and N. Paver | Positron Polarization at the International Linear Collider | Invited talk at 2005 International Linear Collider Workshop, Stanford
Ca (LCWS05) 6 pages, LaTeX, 2 eps figures | null | null | CERN-PH-TH/2005-127 | hep-ph | null | We review some recent arguments supporting the upgrade of the International
Linear Collider by a polarized positron beam, in addition to the polarized
electron beam. The examples presented here mainly focus on the impact of
positron polarization on items relevant to new physics searches, such as the
identification of novel interactions in fermion-pair production and the
formulation of new CP-sensitive observables. In particular, in addition to the
benefits from positron and electron longitudinal polarizations, the advantages
in this field of having transverse polarization of both beams are emphasized.
| [
{
"created": "Fri, 15 Jul 2005 10:04:49 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Osland",
"P.",
""
],
[
"Paver",
"N.",
""
]
] | We review some recent arguments supporting the upgrade of the International Linear Collider by a polarized positron beam, in addition to the polarized electron beam. The examples presented here mainly focus on the impact of positron polarization on items relevant to new physics searches, such as the identification of novel interactions in fermion-pair production and the formulation of new CP-sensitive observables. In particular, in addition to the benefits from positron and electron longitudinal polarizations, the advantages in this field of having transverse polarization of both beams are emphasized. |
hep-ph/0211303 | Adam K. Leibovich | Sean Fleming and Adam K. Leibovich | The Resummed Photon Spectrum in Radiative Upsilon Decays | 4 pages, 6 figures | Phys.Rev.Lett. 90 (2003) 032001 | 10.1103/PhysRevLett.90.032001 | CMU-HEP02-14 and FERMILAB-Pub-02/296-T | hep-ph hep-ex | null | We present a theoretical prediction for the photon spectrum in radiative
Upsilon decay including the effects of resumming the endpoint region, E_\gamma
-> M_\Upsilon/2. Our approach is based on NRQCD and the soft collinear
effective theory. We find that our results give much better agreement with data
than the leading order NRQCD prediction.
| [
{
"created": "Tue, 19 Nov 2002 16:42:30 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Nov 2002 05:35:00 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Fleming",
"Sean",
""
],
[
"Leibovich",
"Adam K.",
""
]
] | We present a theoretical prediction for the photon spectrum in radiative Upsilon decay including the effects of resumming the endpoint region, E_\gamma -> M_\Upsilon/2. Our approach is based on NRQCD and the soft collinear effective theory. We find that our results give much better agreement with data than the leading order NRQCD prediction. |
2311.00758 | Shantanu Sahoo | Aritra Biswas, Soumitra Nandi and Shantanu Sahoo | Analyzing the semileptonic and nonleptonic $B_c \to J/\psi, \eta_c$
decays | 27 Pages, 7 Figures | null | null | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This study focuses on the decay of the $B_c$ meson to S-wave charmonia. Using
lattice inputs on $B_c\to J/\psi$ form factors, we have obtained the
$B_c\to\eta_c$ form factors using heavy quark spin symmetry (HQSS) relations
between the associated form factors after parametrizing and extracting the
possible symmetry breaking corrections. Using the $q^2$ shapes of these form
factors, we have extracted the branching fractions $\mathcal{B}(B_c^-\to
\eta_c\ell^-\bar{\nu})$ (with $\ell =\tau, \mu (e)$) and the decay rate
distributions and have predicted the Standard model estimate for the observable
$R(\eta_c)=\Gamma(B_c^-\to \eta_c\tau^-\bar{\nu})/\Gamma(B_c^-\to
\eta_c\mu^-\bar{\nu}) = 0.302 \pm 0.010$. In addition, we have extracted the
radial wave functions $\psi_{B_c}^R(0)$, $\psi_{J/\psi}^R(0)$ and
$\psi_{\eta_c}^R(0)$ at small quark-antiquark distances from the available
information on the form factors from lattice and experimental data on radiative
and rare decays of the $J/\psi$ and $\eta_c$ mesons. To do so, we choose the
theory framework of nonrelativistic QCD (NRQCD) effective theory. Using our
results, we have estimated the branching fractions of a few non-leptonic decays
of $B_c$ to $J/\psi$ or $\eta_c$ and other light mesons. We have also updated
the numerical estimates of the cross sections $\sigma(e^+e^- \to J/\psi \eta_c,
\eta_c\gamma)$ and predicted the branching fractions of $Z$ boson decays to
either $J/\psi$ or $\eta_c$ final states or both.
| [
{
"created": "Wed, 1 Nov 2023 18:07:02 GMT",
"version": "v1"
}
] | 2023-11-03 | [
[
"Biswas",
"Aritra",
""
],
[
"Nandi",
"Soumitra",
""
],
[
"Sahoo",
"Shantanu",
""
]
] | This study focuses on the decay of the $B_c$ meson to S-wave charmonia. Using lattice inputs on $B_c\to J/\psi$ form factors, we have obtained the $B_c\to\eta_c$ form factors using heavy quark spin symmetry (HQSS) relations between the associated form factors after parametrizing and extracting the possible symmetry breaking corrections. Using the $q^2$ shapes of these form factors, we have extracted the branching fractions $\mathcal{B}(B_c^-\to \eta_c\ell^-\bar{\nu})$ (with $\ell =\tau, \mu (e)$) and the decay rate distributions and have predicted the Standard model estimate for the observable $R(\eta_c)=\Gamma(B_c^-\to \eta_c\tau^-\bar{\nu})/\Gamma(B_c^-\to \eta_c\mu^-\bar{\nu}) = 0.302 \pm 0.010$. In addition, we have extracted the radial wave functions $\psi_{B_c}^R(0)$, $\psi_{J/\psi}^R(0)$ and $\psi_{\eta_c}^R(0)$ at small quark-antiquark distances from the available information on the form factors from lattice and experimental data on radiative and rare decays of the $J/\psi$ and $\eta_c$ mesons. To do so, we choose the theory framework of nonrelativistic QCD (NRQCD) effective theory. Using our results, we have estimated the branching fractions of a few non-leptonic decays of $B_c$ to $J/\psi$ or $\eta_c$ and other light mesons. We have also updated the numerical estimates of the cross sections $\sigma(e^+e^- \to J/\psi \eta_c, \eta_c\gamma)$ and predicted the branching fractions of $Z$ boson decays to either $J/\psi$ or $\eta_c$ final states or both. |
hep-ph/0103055 | K. Sridhar | K. Sridhar | Constraining the Randall-Sundrum Model Using Diphoton Production at
Hadron Colliders | 8 pages, Latex file + 1 ps figure | JHEP 0105 (2001) 066 | 10.1088/1126-6708/2001/05/066 | TIFR/TH/01-10 | hep-ph | null | Virtual effects of gravitons in the production of diphotons at the upgraded
Tevatron and at the LHC are analysed with the idea of probing the parameter
space of the Randall-Sundrum (RS) model. It is shown that this process yields
stringent constraints on the parameter space of the RS model. We show that data
on diphoton production from Tevatron Run II will be sensitive to a masses of
the first graviton resonance in the range of 700-1150 GeV, while at LHC the
mass range probed will be in the region of 3.5 -- 5.5 TeV.
| [
{
"created": "Tue, 6 Mar 2001 10:36:26 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Sridhar",
"K.",
""
]
] | Virtual effects of gravitons in the production of diphotons at the upgraded Tevatron and at the LHC are analysed with the idea of probing the parameter space of the Randall-Sundrum (RS) model. It is shown that this process yields stringent constraints on the parameter space of the RS model. We show that data on diphoton production from Tevatron Run II will be sensitive to a masses of the first graviton resonance in the range of 700-1150 GeV, while at LHC the mass range probed will be in the region of 3.5 -- 5.5 TeV. |
hep-ph/0405181 | Otavio Socolowski Jr. | O. Socolowski Jr, F. Grassi, Y. Hama and T. Kodama | Fluctuations of the Initial Conditions and the Continuous Emission in
Hydrodynamic Description of Two-Pion Interferometry | 5 pages, 4 figures | Phys.Rev.Lett.93:182301,2004 | 10.1103/PhysRevLett.93.182301 | null | hep-ph | null | Within hydrodynamic approach, we study the Bose-Einstein correlation of
identical pions by taking into account both event-by-event fluctuating initial
conditions and continuous pion emission during the whole development of the hot
and dense matter formed in high-energy collisions. Considerable deviations
occur, compared to the usual hydro calculations with smooth initial conditions
and a sudden freeze-out on a well defined hypersurface. Comparison with data at
RHIC shows that, despite rather rough approximation we used here, this
description can give account of the $m_T$ dependence of $R_L$ and $R_s$ and
improves considerably the one for $R_o$ with respect to the usual version.
| [
{
"created": "Wed, 19 May 2004 03:56:36 GMT",
"version": "v1"
},
{
"created": "Wed, 7 Jul 2004 05:17:49 GMT",
"version": "v2"
},
{
"created": "Thu, 19 Aug 2004 05:07:09 GMT",
"version": "v3"
},
{
"created": "Mon, 6 Sep 2004 04:19:39 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Socolowski",
"O.",
"Jr"
],
[
"Grassi",
"F.",
""
],
[
"Hama",
"Y.",
""
],
[
"Kodama",
"T.",
""
]
] | Within hydrodynamic approach, we study the Bose-Einstein correlation of identical pions by taking into account both event-by-event fluctuating initial conditions and continuous pion emission during the whole development of the hot and dense matter formed in high-energy collisions. Considerable deviations occur, compared to the usual hydro calculations with smooth initial conditions and a sudden freeze-out on a well defined hypersurface. Comparison with data at RHIC shows that, despite rather rough approximation we used here, this description can give account of the $m_T$ dependence of $R_L$ and $R_s$ and improves considerably the one for $R_o$ with respect to the usual version. |
hep-ph/9305268 | Giorgos Leontaris | G.K. Leontaris | A Fermion Mass Matrix Ansatz for the Fipped SU(5) Model | 10 pages,(No figures),IOA-292/93 | null | null | null | hep-ph | null | A fermion mass matrix ansatz is proposed in the context of Grand Unified
Supersymmetric Theories (GUTs). The fermion mass matrices are evolved down to
the electroweak scale by solving the renormalization group equations for the
gauge and Yukawa couplings. Eight inputs are introduced at the GUT scale to
predict the 13 arbitrary parameters of the Standard model. The constraints
imposed by the charged fermion data are used to make predictions in the
neutrino sector. In particular, the neutrino mass matrix is worked out in the
case of the flipped SU(5) model and it is found that the
{\it generalized } see-saw mechanism which occurs naturally in this model can
provide a solution to the solar neutrino puzzle and give a sufficiently large
$\nu_{\tau}$ mass to contribute as a hot dark matter component as indicated by
the recent COBE data.
| [
{
"created": "Fri, 14 May 1993 13:27:52 GMT",
"version": "v1"
},
{
"created": "Tue, 18 May 1993 16:17:29 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Leontaris",
"G. K.",
""
]
] | A fermion mass matrix ansatz is proposed in the context of Grand Unified Supersymmetric Theories (GUTs). The fermion mass matrices are evolved down to the electroweak scale by solving the renormalization group equations for the gauge and Yukawa couplings. Eight inputs are introduced at the GUT scale to predict the 13 arbitrary parameters of the Standard model. The constraints imposed by the charged fermion data are used to make predictions in the neutrino sector. In particular, the neutrino mass matrix is worked out in the case of the flipped SU(5) model and it is found that the {\it generalized } see-saw mechanism which occurs naturally in this model can provide a solution to the solar neutrino puzzle and give a sufficiently large $\nu_{\tau}$ mass to contribute as a hot dark matter component as indicated by the recent COBE data. |
hep-ph/9504311 | W. S. Hou | Wei-Shu Hou and Gwo-Guang Wong | $\mu^+e^- <---> \mu^- e^+$ Transitions via Neutral Scalar Bosons | 12 pages, ReVtex, 3 figures available upon request | Phys.Rev. D53 (1996) 1537-1541 | 10.1103/PhysRevD.53.1537 | NTUTH-95-03 | hep-ph | null | With $\mu\to e\gamma$ decay forbidden by multiplicative lepton number
conservation, we study muonium--antimuonium transitions induced by neutral
scalar bosons. Pseudoscalars do not induce conversion for triplet muonium,
while for singlet muonium, pseudoscalar and scalar contributions add
constructively. This is in contrast to the usual case of doubly charged scalar
exchange, where the conversion rate is the same for both singlet and triplet
muonium. Complementary to muonium conversion studies, high energy $\mu^+e^- \to
\mu^- e^+$ and $e^-e^- \to \mu^- \mu^-$ collisions could reveal spectacular
resonance peaks for the cases of neutral and doubly charged scalars,
respectively.
| [
{
"created": "Mon, 17 Apr 1995 20:07:49 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Hou",
"Wei-Shu",
""
],
[
"Wong",
"Gwo-Guang",
""
]
] | With $\mu\to e\gamma$ decay forbidden by multiplicative lepton number conservation, we study muonium--antimuonium transitions induced by neutral scalar bosons. Pseudoscalars do not induce conversion for triplet muonium, while for singlet muonium, pseudoscalar and scalar contributions add constructively. This is in contrast to the usual case of doubly charged scalar exchange, where the conversion rate is the same for both singlet and triplet muonium. Complementary to muonium conversion studies, high energy $\mu^+e^- \to \mu^- e^+$ and $e^-e^- \to \mu^- \mu^-$ collisions could reveal spectacular resonance peaks for the cases of neutral and doubly charged scalars, respectively. |
2103.00456 | Gaoqing Cao | Gaoqing Cao | Recent progresses on QCD phases in a strong magnetic field -- views from
Nambu--Jona-Lasinio model | null | null | 10.1140/epja/s10050-021-00570-0 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by-nc-sa/4.0/ | In this review, we summarize recent progress on the possible phases of
quantum chromodynamics (QCD) in the presence of a strong magnetic field, mainly
from the views of the chiral effective Nambu--Jona-Lasinio model. Four kinds of
phase transitions are explored in detail: chiral symmetry breaking and
restoration, neutral pseudoscalar superfluidity, charged pion superfluidity and
charged rho superconductivity. In particular, we revisit the unsolved problems
of inverse magnetic catalysis effect and competition between the chiral density
wave and solitonic modulation phases. It is shown that useful results can be
obtained by adopting self-consistent schemes.
| [
{
"created": "Sun, 28 Feb 2021 11:11:04 GMT",
"version": "v1"
},
{
"created": "Sun, 11 Jul 2021 02:45:47 GMT",
"version": "v2"
},
{
"created": "Tue, 17 Aug 2021 02:16:23 GMT",
"version": "v3"
}
] | 2023-02-22 | [
[
"Cao",
"Gaoqing",
""
]
] | In this review, we summarize recent progress on the possible phases of quantum chromodynamics (QCD) in the presence of a strong magnetic field, mainly from the views of the chiral effective Nambu--Jona-Lasinio model. Four kinds of phase transitions are explored in detail: chiral symmetry breaking and restoration, neutral pseudoscalar superfluidity, charged pion superfluidity and charged rho superconductivity. In particular, we revisit the unsolved problems of inverse magnetic catalysis effect and competition between the chiral density wave and solitonic modulation phases. It is shown that useful results can be obtained by adopting self-consistent schemes. |
1101.5855 | Lusaka Bhattacharya | Mahatsab Mandal, Lusaka Bhattacharya and Pradip Roy | Nuclear modification factor in an anisotropic {\em Quark-Gluon-Plasma} | 18 pages, 9 eps figures, Accepted for publication in Physical Review
C | null | 10.1103/PhysRevC.84.044910 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the nuclear modification factor ($R_{AA}$) of light hadrons by
taking into account the initial state momentum anisotropy of the quark gluon
plasma (QGP) expected to be formed in relativistic heavy ion collisions. Such
an anisotropy can result from the initial rapid longitudinal expansion of the
matter. A phenomenological model for the space time evolution of the
anisotropic QGP is used to obtain the time dependence of the anisotropy
parameter $\xi$ and the hard momentum scale, $p_{\rm hard}$. The result is then
compared with the PHENIX experimental data to constrain the isotropization time
scale, $\tau_{\rm iso}$ for fixed initial conditions (FIC). It is shown that
the extracted value of $\tau_{\rm iso}$ lies in the range $0.5 \leq \tau_{\rm
iso} \leq 1.5$. However, using fixed final multiplicity (FFM) condition does
not lead to any firm conclusion about the extraction of the isotropization
time. The present calculation is also extended to contrast with the recent
measurement of nuclear modification factor by ALICE collaboration at
$\sqrt{s}=2.76$ TeV. It is argued that in the present approach, the extraction
of $\tau_{\rm iso}$ at this energy is uncertain and, therfore, refinement of
the model is necessary. The sensitivity of the results on the initial
conditions has been discussed. We also present the nuclear modification factor
at LHC energies with $\sqrt{s} = 5.5$ TeV.
| [
{
"created": "Mon, 31 Jan 2011 06:32:47 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Sep 2011 20:20:03 GMT",
"version": "v2"
}
] | 2015-05-27 | [
[
"Mandal",
"Mahatsab",
""
],
[
"Bhattacharya",
"Lusaka",
""
],
[
"Roy",
"Pradip",
""
]
] | We calculate the nuclear modification factor ($R_{AA}$) of light hadrons by taking into account the initial state momentum anisotropy of the quark gluon plasma (QGP) expected to be formed in relativistic heavy ion collisions. Such an anisotropy can result from the initial rapid longitudinal expansion of the matter. A phenomenological model for the space time evolution of the anisotropic QGP is used to obtain the time dependence of the anisotropy parameter $\xi$ and the hard momentum scale, $p_{\rm hard}$. The result is then compared with the PHENIX experimental data to constrain the isotropization time scale, $\tau_{\rm iso}$ for fixed initial conditions (FIC). It is shown that the extracted value of $\tau_{\rm iso}$ lies in the range $0.5 \leq \tau_{\rm iso} \leq 1.5$. However, using fixed final multiplicity (FFM) condition does not lead to any firm conclusion about the extraction of the isotropization time. The present calculation is also extended to contrast with the recent measurement of nuclear modification factor by ALICE collaboration at $\sqrt{s}=2.76$ TeV. It is argued that in the present approach, the extraction of $\tau_{\rm iso}$ at this energy is uncertain and, therfore, refinement of the model is necessary. The sensitivity of the results on the initial conditions has been discussed. We also present the nuclear modification factor at LHC energies with $\sqrt{s} = 5.5$ TeV. |
1109.0125 | Chung-Lin Shan | Chung-Lin Shan | Analyzing Direct Dark Matter Detection Data by the AMIDAS Website | 12 pages, 8 eps figures, 1 table, to appear in the proceedings of the
3rd Workshop on Directional Detection of Dark Matter (CYGNUS 2011), June
7-10, 2011, Aussois, France | null | 10.1051/eas/1253010 | null | hep-ph astro-ph.HE hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk I have presented the data analysis results of extracting
properties of halo WIMPs: the mass and the (ratios between the)
spin-independent and spin-dependent couplings/cross sections on nucleons by the
AMIDAS website. Although non-standard astronomical setup has been used to
generate pseudodata sets for our analyses, it has been found that, without
prior information/assumption about the local density and velocity distribution
of halo Dark Matter, these WIMP properties have been reconstructed with ~5% to
< ~40% deviations from the input values.
| [
{
"created": "Thu, 1 Sep 2011 08:36:12 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Shan",
"Chung-Lin",
""
]
] | In this talk I have presented the data analysis results of extracting properties of halo WIMPs: the mass and the (ratios between the) spin-independent and spin-dependent couplings/cross sections on nucleons by the AMIDAS website. Although non-standard astronomical setup has been used to generate pseudodata sets for our analyses, it has been found that, without prior information/assumption about the local density and velocity distribution of halo Dark Matter, these WIMP properties have been reconstructed with ~5% to < ~40% deviations from the input values. |
hep-ph/9404280 | Mary Louise Stong | M. Kraemer, J. Kuehn, M. L. Stong, and P. M. Zerwas | Prospects of Measuring the Parity of Higgs Particles | 18 pages, Latex, with uuencoded figures. Postscript files for text
and figures are available via anonymous ftp at ttpux2.physik.uni-karlsruhe.de
(129.13.102.139) as ttp93-41/ttp93-41.ps and ttp93-41/fig*.ps, Local
preprint#s DESY 93-174, TTP 93-41 | Z.Phys. C64 (1994) 21-30 | 10.1007/BF01557231 | null | hep-ph | null | We analyze the prospects of measuring the parity of Higgs particles in the
Standard Model and its supersymmetric extensions. Higgs decays are discussed in
this context as well as production processes including, in particular, the
fusion of Higgs particles in linearly polarized photon--photon collisions.
| [
{
"created": "Mon, 18 Apr 1994 09:14:29 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Kraemer",
"M.",
""
],
[
"Kuehn",
"J.",
""
],
[
"Stong",
"M. L.",
""
],
[
"Zerwas",
"P. M.",
""
]
] | We analyze the prospects of measuring the parity of Higgs particles in the Standard Model and its supersymmetric extensions. Higgs decays are discussed in this context as well as production processes including, in particular, the fusion of Higgs particles in linearly polarized photon--photon collisions. |
hep-ph/9804287 | Stephane Keller | S. Keller | Theoretical Uncertainties Associated with the Extraction of M_W at
Hadron Colliders | Talk presented at the XXXIIIrd Rencontres de Moriond on "QCD and High
Energy Hadronic Inteactions" | null | null | Fermilab-Conf-98/106-T | hep-ph | null | In this contribution I briefly summarize several topics related to the
measurement of the W-boson mass, M_W, at hadron colliders.
| [
{
"created": "Tue, 14 Apr 1998 19:33:44 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Keller",
"S.",
""
]
] | In this contribution I briefly summarize several topics related to the measurement of the W-boson mass, M_W, at hadron colliders. |
hep-ph/0611217 | Marcelo Chiapparini Dr. | M.E. Bracco, A. Lozea, A. Cerqueira Jr., M. Chiapparini and M. Nielsen | Coupling constants of $D^*D_sK$ and $D_s^*DK$ processes | 4 pages, 3 ps figures. Talk presented in the 18 Workshop on Hadron
Interactions, IFUSP, Sao Paulo, Brazil, may 22-24 of 2006 | Braz.J.Phys.37:59-62,2007 | 10.1590/S0103-97332007000100019 | null | hep-ph | null | We calculate the coupling constants of $D^*D_sK$ and $D_s^*DK$ vertices using
the QCD sum rules technique. We compare results obtained in the limit of SU(4)
symmetry and found that the symmetry is broken on the order of 40%.
| [
{
"created": "Thu, 16 Nov 2006 14:07:06 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Jan 2007 15:07:38 GMT",
"version": "v2"
}
] | 2011-08-04 | [
[
"Bracco",
"M. E.",
""
],
[
"Lozea",
"A.",
""
],
[
"Cerqueira",
"A.",
"Jr."
],
[
"Chiapparini",
"M.",
""
],
[
"Nielsen",
"M.",
""
]
] | We calculate the coupling constants of $D^*D_sK$ and $D_s^*DK$ vertices using the QCD sum rules technique. We compare results obtained in the limit of SU(4) symmetry and found that the symmetry is broken on the order of 40%. |
hep-ph/0503297 | Zhi-Gang Wang | Zhi-Gang Wang, Wei-Min Yang, Shao-Long Wan | Analysis the $0^{++}$ nonet mesons as four-quark states with the QCD sum
rules | 11 pages, revised version | J.Phys.G31:971-979,2005 | 10.1088/0954-3899/31/8/025 | null | hep-ph | null | In this article, we take the point of view that the $0^{++}$ nonet mesons
below $1 GeV$ are diquark-antidiquark states
$(qq)_{\bar{3}}(\bar{q}\bar{q})_3$, and devote to determine their masses in the
framework of the QCD sum rules approach with the interpolating currents
constructed from scalar-scalar type and pseudoscalar-pseudoscalar type diquark
pairs respectively. The numerical results indicate that the $0^{++}$ nonet
mesons may have two possible diquark-antidiquark substructures.
| [
{
"created": "Thu, 31 Mar 2005 12:57:37 GMT",
"version": "v1"
},
{
"created": "Mon, 30 May 2005 02:25:34 GMT",
"version": "v2"
}
] | 2011-08-23 | [
[
"Wang",
"Zhi-Gang",
""
],
[
"Yang",
"Wei-Min",
""
],
[
"Wan",
"Shao-Long",
""
]
] | In this article, we take the point of view that the $0^{++}$ nonet mesons below $1 GeV$ are diquark-antidiquark states $(qq)_{\bar{3}}(\bar{q}\bar{q})_3$, and devote to determine their masses in the framework of the QCD sum rules approach with the interpolating currents constructed from scalar-scalar type and pseudoscalar-pseudoscalar type diquark pairs respectively. The numerical results indicate that the $0^{++}$ nonet mesons may have two possible diquark-antidiquark substructures. |
hep-ph/0107248 | Andrey Grozin | A.G. Grozin | Renormalization of HQET at Three Loops | Talk at the QCD workshop, Martina Franca, 17-20 June, to be published
in the Proceedings; LaTeX2e, aipproc document class (included), 7 pages, 7
eps figures (included) | AIP Conf.Proc. 602 (2001) 271-277 | 10.1063/1.1435937 | null | hep-ph | null | Three-loop propagator diagrams in HQET can be reduced, using integration by
parts, to 8 basis integrals: 5 trivial ones, two expressible via 3F2, and one
only known up to \epsilon^0. Calculation of the heavy-quark propagator in HQET
is considerably simplified by the non-abelian exponentiation theorem.
| [
{
"created": "Tue, 24 Jul 2001 13:17:54 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Jul 2001 03:32:13 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Grozin",
"A. G.",
""
]
] | Three-loop propagator diagrams in HQET can be reduced, using integration by parts, to 8 basis integrals: 5 trivial ones, two expressible via 3F2, and one only known up to \epsilon^0. Calculation of the heavy-quark propagator in HQET is considerably simplified by the non-abelian exponentiation theorem. |
1106.5085 | Xiao-Gang He | N.G. Deshpande, T. Enkhbat, T. Fukuyama, X.-G. He, L.-H. Tsai, K.
Tsumura | $\mu - e$ Conversion With Four Generations | Latex 11 pages with 3 figures. An error in figure corrected | null | 10.1016/j.physletb.2011.08.045 | MISC-2011-13 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study $\mu - e$ conversion with sequential four generations. A large mass
for the fourth generation neutrino can enhance the conversion rate by orders of
magnitude. We compare constraints obtained from $\mu - e$ conversion using
experimental bounds on various nuclei with those from $\mu \to e \gamma$ and
$\mu \to e\bar e e$. We find that the current bound from $\mu - e$ conversion
with Au puts the most stringent constraint in this model. The relevant flavor
changing parameter $\lambda_{\mu e} = V^*_{\mu 4}V_{e4}^{}$ is constrained to
be less than $1.6\times 10^{-5}$ for the fourth generation neutrino mass larger
than 100 GeV. Implications for future $\mu -e$ conversion, $\mu \to e\gamma$
and $\mu \to e\bar e e$ experiments are discussed.
| [
{
"created": "Sat, 25 Jun 2011 00:43:25 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Jul 2011 04:03:39 GMT",
"version": "v2"
},
{
"created": "Mon, 4 Jul 2011 06:30:43 GMT",
"version": "v3"
}
] | 2015-05-28 | [
[
"Deshpande",
"N. G.",
""
],
[
"Enkhbat",
"T.",
""
],
[
"Fukuyama",
"T.",
""
],
[
"He",
"X. -G.",
""
],
[
"Tsai",
"L. -H.",
""
],
[
"Tsumura",
"K.",
""
]
] | We study $\mu - e$ conversion with sequential four generations. A large mass for the fourth generation neutrino can enhance the conversion rate by orders of magnitude. We compare constraints obtained from $\mu - e$ conversion using experimental bounds on various nuclei with those from $\mu \to e \gamma$ and $\mu \to e\bar e e$. We find that the current bound from $\mu - e$ conversion with Au puts the most stringent constraint in this model. The relevant flavor changing parameter $\lambda_{\mu e} = V^*_{\mu 4}V_{e4}^{}$ is constrained to be less than $1.6\times 10^{-5}$ for the fourth generation neutrino mass larger than 100 GeV. Implications for future $\mu -e$ conversion, $\mu \to e\gamma$ and $\mu \to e\bar e e$ experiments are discussed. |
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