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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1301.5145 | Seyed Yaser Ayazi | Seyed Yaser Ayazi and Mojtaba Mohammadi Najafabadi | Impact of Torsion Space-Time on $t\bar{t}$ observables at Hadron
Colliders | 17 pages, 6 figures. arXiv admin note: substantial text overlap with
arXiv:1207.0643 | J.Phys. G40 (2013) 095002 | 10.1088/0954-3899/40/9/095002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Starting from the effective torsion space-time model, we study its effects on
the top pair production cross section at hadron colliders. We also study the
effect of this model on top pair asymmetries at the Tevatron and the LHC. We
find that torsion space-time can explain forward-backward asymmetry according
to measured anomaly at Tevatron. We find an allowed region in the parameters
space which can satisfy simultaneously all $t\bar{t}$ observables measured at
Tevatron and LHC.
| [
{
"created": "Tue, 22 Jan 2013 11:12:10 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Apr 2013 12:26:46 GMT",
"version": "v2"
}
] | 2015-06-12 | [
[
"Ayazi",
"Seyed Yaser",
""
],
[
"Najafabadi",
"Mojtaba Mohammadi",
""
]
] | Starting from the effective torsion space-time model, we study its effects on the top pair production cross section at hadron colliders. We also study the effect of this model on top pair asymmetries at the Tevatron and the LHC. We find that torsion space-time can explain forward-backward asymmetry according to measured anomaly at Tevatron. We find an allowed region in the parameters space which can satisfy simultaneously all $t\bar{t}$ observables measured at Tevatron and LHC. |
1603.07053 | Alan Chodos | Alan Chodos | Gauge Interactions and a Quantum Avatar in a Model with Light Cone
Reflection Symmetry | 12 pages, no figures | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We continue the development of a model of neutrinos that possesses a new
symmetry, Light Cone Reflection, interchanging spacelike and timelike
intervals. In this paper we introduce gauge interactions in which only the
physical modes of the theory participate. We also find an avatar of the theory,
involving spinors in two-dimensions that obey equations reproducing the
spectrum of the original, four-dimensional theory, and we discuss the
quantization of the avatar.
| [
{
"created": "Wed, 23 Mar 2016 02:36:58 GMT",
"version": "v1"
}
] | 2016-03-24 | [
[
"Chodos",
"Alan",
""
]
] | We continue the development of a model of neutrinos that possesses a new symmetry, Light Cone Reflection, interchanging spacelike and timelike intervals. In this paper we introduce gauge interactions in which only the physical modes of the theory participate. We also find an avatar of the theory, involving spinors in two-dimensions that obey equations reproducing the spectrum of the original, four-dimensional theory, and we discuss the quantization of the avatar. |
hep-ph/0203032 | Apostolos Pilaftsis | Alexander M\"uck (W\"urzburg U.), Apostolos Pilaftsis (Manchester U.)
and Reinhold R\"uckl (W\"urzburg U.) | Electroweak Constraints on Minimal Higher-Dimensional Extensions of the
Standard Model | To appear in the proceedings of the Summer School on High Energy
Physics in Corfu, Greece, September 2001 | null | null | MC-TH-2002-01 and WUE-ITP-2002-001 | hep-ph | null | We derive electroweak constraints on the compactification scale of minimal
5-dimensional extensions of the Standard Model, in which all or only some of
the SU(2)$_L$ and U(1)$_Y$ gauge fields and Higgs bosons feel the presence of
the fifth dimension. In our analysis, we assume that the fermions are always
localized on a 3-brane. In this context, we also present the consistent
quantization procedure of the higher-dimensional models in the generalized
$R_\xi$ gauge. We find that the usually derived lower bound of $\sim 4$ TeV on
the compactification scale may be significantly lowered to $\sim 3$ TeV if the
SU(2)$_L$ gauge boson is the only particle that propagates in all 5 dimensions.
| [
{
"created": "Mon, 4 Mar 2002 20:06:25 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mück",
"Alexander",
"",
"Würzburg U."
],
[
"Pilaftsis",
"Apostolos",
"",
"Manchester U."
],
[
"Rückl",
"Reinhold",
"",
"Würzburg U."
]
] | We derive electroweak constraints on the compactification scale of minimal 5-dimensional extensions of the Standard Model, in which all or only some of the SU(2)$_L$ and U(1)$_Y$ gauge fields and Higgs bosons feel the presence of the fifth dimension. In our analysis, we assume that the fermions are always localized on a 3-brane. In this context, we also present the consistent quantization procedure of the higher-dimensional models in the generalized $R_\xi$ gauge. We find that the usually derived lower bound of $\sim 4$ TeV on the compactification scale may be significantly lowered to $\sim 3$ TeV if the SU(2)$_L$ gauge boson is the only particle that propagates in all 5 dimensions. |
1912.02760 | Ignacio Fabre | Daniel de Florian, Ignacio Fabre and Javier Mazzitelli | Triple Higgs production at hadron colliders at NNLO in QCD | 22 pages, 7 figures, 2 tables; typos corrected, references added,
matches published version | J. High Energ. Phys. 2020, 155 (2020) | 10.1007/JHEP03(2020)155 | ICAS 046/19, ZU-TH 51/19, MPP-2019-245 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we analyse the triple Higgs boson production cross section at
hadron colliders via gluon fusion, and present for the first time the full set
of QCD NNLO corrections in the heavy top limit. In order to account for finite
top mass effects we perform two different reweighting procedures, and study the
dependence of the result on the choice of the approximation. Combining the most
accurate predictions available to date, we present the following result for the
total NNLO cross section for triple Higgs boson production at a 100 TeV
collider: $\sigma_\text{NNLO}=5.56^{+5\%}_{-6\%} \pm 20\%$ fb, where the first
uncertainty is an estimate for higher order effects from scale variations,
while the last one is an estimate for the missing finite top mass effects.
| [
{
"created": "Thu, 5 Dec 2019 17:53:00 GMT",
"version": "v1"
},
{
"created": "Sun, 29 Mar 2020 17:45:48 GMT",
"version": "v2"
}
] | 2020-03-31 | [
[
"de Florian",
"Daniel",
""
],
[
"Fabre",
"Ignacio",
""
],
[
"Mazzitelli",
"Javier",
""
]
] | In this work we analyse the triple Higgs boson production cross section at hadron colliders via gluon fusion, and present for the first time the full set of QCD NNLO corrections in the heavy top limit. In order to account for finite top mass effects we perform two different reweighting procedures, and study the dependence of the result on the choice of the approximation. Combining the most accurate predictions available to date, we present the following result for the total NNLO cross section for triple Higgs boson production at a 100 TeV collider: $\sigma_\text{NNLO}=5.56^{+5\%}_{-6\%} \pm 20\%$ fb, where the first uncertainty is an estimate for higher order effects from scale variations, while the last one is an estimate for the missing finite top mass effects. |
2104.07520 | Jin Zhang | Jin Zhang | Scalar one-loop 4-point integral with one massless vertex in loop
regularization | 31 pages, 1 figure | null | 10.1088/1572-9494/ac0ce2 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The scalar one-loop 4-point function with one massless vertex is evaluated
analytically by employing the loop regularization method. According to the
method a characteristic scale $\mu_{s}$ is introduced to regularize the
divergent integrals. The infrared divergent parts, which take the form of
$\ln^{2}(\lambda^{2}/\mu^{2}_{s})$ and $\ln(\lambda^{2}/\mu^{2}_{s})$ as
$\mu_{s}\rightarrow 0$ where $\lambda$ is a constant and expressed in terms of
masses and Mandelstam variables, and the infrared stable parts are well
separated. The result is shown explicitly via $44$ dilogarithms in the
kinematic sector in which our evaluation is valid.
| [
{
"created": "Thu, 15 Apr 2021 15:18:16 GMT",
"version": "v1"
}
] | 2021-09-01 | [
[
"Zhang",
"Jin",
""
]
] | The scalar one-loop 4-point function with one massless vertex is evaluated analytically by employing the loop regularization method. According to the method a characteristic scale $\mu_{s}$ is introduced to regularize the divergent integrals. The infrared divergent parts, which take the form of $\ln^{2}(\lambda^{2}/\mu^{2}_{s})$ and $\ln(\lambda^{2}/\mu^{2}_{s})$ as $\mu_{s}\rightarrow 0$ where $\lambda$ is a constant and expressed in terms of masses and Mandelstam variables, and the infrared stable parts are well separated. The result is shown explicitly via $44$ dilogarithms in the kinematic sector in which our evaluation is valid. |
hep-ph/9803493 | Oleg Veretin | J. Fleischer, F. Jegerlehner, O.V. Tarasov, O.L. Veretin | Two-loop QCD corrections of the massive fermion propagator | 18 pages LaTeX, misprints in formula (12) are corrected | Nucl.Phys. B539 (1999) 671-690; Erratum-ibid. B571 (2000) 511-512 | 10.1016/S0550-3213(98)00705-6 | null | hep-ph | null | The off-shell two-loop correction to the massive quark propagator in an
arbitrary covariant gauge is calculated and results for the bare and
renormalized propagator are presented. The calculations were performed by means
of a set of new generalized recurrence relations proposed recently by one of
the authors. From the position of the pole of the renormalized propagator we
obtain the relationship between the pole mass and the \bar{MS} mass. This
relation confirms the known result by Gray et al.. The bare amplitudes are
given for an arbitrary gauge group and for arbitrary space-time dimensions.
| [
{
"created": "Tue, 31 Mar 1998 11:38:44 GMT",
"version": "v1"
},
{
"created": "Tue, 5 May 1998 12:02:56 GMT",
"version": "v2"
},
{
"created": "Mon, 4 Jan 1999 10:54:37 GMT",
"version": "v3"
},
{
"created": "Tue, 9 Mar 1999 15:01:08 GMT",
"version": "v4"
},
{
"crea... | 2009-10-31 | [
[
"Fleischer",
"J.",
""
],
[
"Jegerlehner",
"F.",
""
],
[
"Tarasov",
"O. V.",
""
],
[
"Veretin",
"O. L.",
""
]
] | The off-shell two-loop correction to the massive quark propagator in an arbitrary covariant gauge is calculated and results for the bare and renormalized propagator are presented. The calculations were performed by means of a set of new generalized recurrence relations proposed recently by one of the authors. From the position of the pole of the renormalized propagator we obtain the relationship between the pole mass and the \bar{MS} mass. This relation confirms the known result by Gray et al.. The bare amplitudes are given for an arbitrary gauge group and for arbitrary space-time dimensions. |
2407.07142 | Yu-Dai Tsai | Yu-Dai Tsai, Insung Hwang, Ryan Schmitz, Matthew Citron, Kranti
Gunthoti, Jacob Steenis, Hoyong Jeong, Hyunki Moon, Jae Hyeok Yoo, Ming Xiong
Liu | LANSCE-mQ: Dedicated search for milli/fractionally charged particles at
LANL | 8 pages, 8 figures | null | null | FERMILAB-PUB-24-0357-T-V; LA-UR-24-27441 | hep-ph astro-ph.CO hep-ex hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we propose an experiment, LANSCE-mQ, aiming to detect
fractionally charged and millicharged particles (mCP) using an 800 MeV proton
beam fixed target at the Los Alamos Neutron Science Center (LANSCE) facility.
This search can shed new light on numerous fundamental questions, including
charge quantization, the predictions of string theories and grand unification
theories, the gauge symmetry of the Standard Model, dark sector models, and the
tests of cosmic reheating. We propose to install two-layer scintillation
detectors made of plastic (such as EJ-200) or CeBr3 to search for mCPs.
Dedicated Geant4 detector simulations and in situ measurements have been
conducted to obtain a preliminary determination of the background rate. The
dominant backgrounds are beam-induced neutrons and coincident dark current
signals from the photomultiplier tubes, while beam-induced gammas and cosmic
muons are subdominant. We determined that LANSCE-mQ, the dedicated mCP
experiment, has the leading mCP sensitivity for mass between ~ 1 MeV to 300
MeV.
| [
{
"created": "Tue, 9 Jul 2024 18:00:00 GMT",
"version": "v1"
}
] | 2024-07-19 | [
[
"Tsai",
"Yu-Dai",
""
],
[
"Hwang",
"Insung",
""
],
[
"Schmitz",
"Ryan",
""
],
[
"Citron",
"Matthew",
""
],
[
"Gunthoti",
"Kranti",
""
],
[
"Steenis",
"Jacob",
""
],
[
"Jeong",
"Hoyong",
""
],
[
"Moo... | In this paper, we propose an experiment, LANSCE-mQ, aiming to detect fractionally charged and millicharged particles (mCP) using an 800 MeV proton beam fixed target at the Los Alamos Neutron Science Center (LANSCE) facility. This search can shed new light on numerous fundamental questions, including charge quantization, the predictions of string theories and grand unification theories, the gauge symmetry of the Standard Model, dark sector models, and the tests of cosmic reheating. We propose to install two-layer scintillation detectors made of plastic (such as EJ-200) or CeBr3 to search for mCPs. Dedicated Geant4 detector simulations and in situ measurements have been conducted to obtain a preliminary determination of the background rate. The dominant backgrounds are beam-induced neutrons and coincident dark current signals from the photomultiplier tubes, while beam-induced gammas and cosmic muons are subdominant. We determined that LANSCE-mQ, the dedicated mCP experiment, has the leading mCP sensitivity for mass between ~ 1 MeV to 300 MeV. |
1404.2572 | Sandra Robles | D. G. Cerdeno, M. Peiro, S. Robles | Low-mass right-handed sneutrino dark matter: SuperCDMS and LUX
constraints and the Galactic Centre gamma-ray excess | 31 pages, 13 figures. Discussion extended, matches JCAP accepted
version | JCAP 08 (2014) 005 | 10.1088/1475-7516/2014/08/005 | IFT-UAM/CSIC-14-031; FTUAM-14-14 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent results from direct and indirect searches for dark matter (DM) have
motivated the study of particle physics models that can provide weakly
interacting massive particles (WIMPs) in the mass range 1-50 GeV. Viable
candidates for light WIMP DM must fulfil stringent constraints. On the one
hand, the observation at the LHC of a Higgs boson with Standard Model
properties set an upper bound on the coupling of light DM particles to the
Higgs, thereby making it difficult to reproduce the correct relic abundance. On
the other hand, the recent results from direct searches in the CDMSlite,
SuperCDMS and LUX experiments have set upper constraints on the DM scattering
cross section. In this paper, we investigate the viability of light
right-handed sneutrino DM in the Next-to-Minimal Supersymmetric Model (NMSSM)
in the light of these constraints. To this aim, we have carried out a scan in
the NMSSM parameter space, imposing experimental bounds on the Higgs sector and
low-energy observables, such as the muon anomalous magnetic moment and
branching ratios of rare decays. We demonstrate that the enlarged Higgs sector
of the NMSSM, together with the flexibility provided by the RH sneutrino
parameters, make it possible to obtain viable RH sneutrino DM with a mass as
light as 2 GeV. We have also considered the upper bounds on the annihilation
cross section from Fermi LAT data on dwarf spheroidal galaxies, and extracted
specific examples with mass in the range 8-50 GeV that could account for the
apparent low-energy excess in the gamma-ray emission at the Galactic Centre.
Then, we have computed the theoretical predictions for the elastic scattering
cross-section of RH sneutrinos. Finally, after imposing the recent bounds from
SuperCDMS and LUX, we have found a wide area of the parameter space that could
be probed by future low-threshold direct detection experiments.
| [
{
"created": "Wed, 9 Apr 2014 18:35:59 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Apr 2014 18:50:56 GMT",
"version": "v2"
},
{
"created": "Sat, 26 Jul 2014 11:40:40 GMT",
"version": "v3"
}
] | 2014-08-05 | [
[
"Cerdeno",
"D. G.",
""
],
[
"Peiro",
"M.",
""
],
[
"Robles",
"S.",
""
]
] | Recent results from direct and indirect searches for dark matter (DM) have motivated the study of particle physics models that can provide weakly interacting massive particles (WIMPs) in the mass range 1-50 GeV. Viable candidates for light WIMP DM must fulfil stringent constraints. On the one hand, the observation at the LHC of a Higgs boson with Standard Model properties set an upper bound on the coupling of light DM particles to the Higgs, thereby making it difficult to reproduce the correct relic abundance. On the other hand, the recent results from direct searches in the CDMSlite, SuperCDMS and LUX experiments have set upper constraints on the DM scattering cross section. In this paper, we investigate the viability of light right-handed sneutrino DM in the Next-to-Minimal Supersymmetric Model (NMSSM) in the light of these constraints. To this aim, we have carried out a scan in the NMSSM parameter space, imposing experimental bounds on the Higgs sector and low-energy observables, such as the muon anomalous magnetic moment and branching ratios of rare decays. We demonstrate that the enlarged Higgs sector of the NMSSM, together with the flexibility provided by the RH sneutrino parameters, make it possible to obtain viable RH sneutrino DM with a mass as light as 2 GeV. We have also considered the upper bounds on the annihilation cross section from Fermi LAT data on dwarf spheroidal galaxies, and extracted specific examples with mass in the range 8-50 GeV that could account for the apparent low-energy excess in the gamma-ray emission at the Galactic Centre. Then, we have computed the theoretical predictions for the elastic scattering cross-section of RH sneutrinos. Finally, after imposing the recent bounds from SuperCDMS and LUX, we have found a wide area of the parameter space that could be probed by future low-threshold direct detection experiments. |
1311.1092 | Jens Krog Mr. | Oleg Antipin, Jens Krog, Matin Mojaza, Francesco Sannino | Stable Extensions with(out) Gravity | 12 pages, 4 figures | Nucl.Phys. B886 (2014) 125-134 | 10.1016/j.nuclphysb.2014.06.023 | CP3-Origins-2013-44, DIAS-2013-44 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the vacuum stability as well as the gravitational corrections
in extensions of the Standard Model featuring a new complex scalar, and two
Dirac fermions for different choices of the hypercharge of the scalar and one
of the two fermions. The neutral fermion acquires loop-induced magnetic
interactions with the Standard Model and could be identified with a dark matter
candidate. To the lowest order in perturbation theory we show that these
extensions can save the electroweak vacuum from being metastable. We then add
the gravitational corrections to the different beta functions and discover that
the models can be compatible with the asymptotically safe gravity scenario at
the price of a heavier Higgs and lighter top mass.
| [
{
"created": "Tue, 5 Nov 2013 15:44:15 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Jul 2014 16:04:50 GMT",
"version": "v2"
}
] | 2014-07-31 | [
[
"Antipin",
"Oleg",
""
],
[
"Krog",
"Jens",
""
],
[
"Mojaza",
"Matin",
""
],
[
"Sannino",
"Francesco",
""
]
] | We investigate the vacuum stability as well as the gravitational corrections in extensions of the Standard Model featuring a new complex scalar, and two Dirac fermions for different choices of the hypercharge of the scalar and one of the two fermions. The neutral fermion acquires loop-induced magnetic interactions with the Standard Model and could be identified with a dark matter candidate. To the lowest order in perturbation theory we show that these extensions can save the electroweak vacuum from being metastable. We then add the gravitational corrections to the different beta functions and discover that the models can be compatible with the asymptotically safe gravity scenario at the price of a heavier Higgs and lighter top mass. |
hep-ph/9602391 | Biswa | Mar Bastero-Gil (SISSA) and Biswajoy Brahmachari (ICTP) | Two-loop renormalization group analysis of supersymmetric SO(10) models
with an intermediate scale | 31 pages and 12 figures, typographical errors are corrected, one new
paragraph is added, local preprint number is corrected, some new references
are added, conclusions are unchanged | Nucl.Phys. B482 (1996) 39-58 | 10.1016/S0550-3213(96)00472-5 | IC/96/43 | hep-ph | null | Two-loop evolutions of the gauge couplings in a class of intermediate scale
supersymmetric SO(10) models including the effect of third generation Yukawa
couplings are studied. The unification scale, the intermediate scale and the
value of the unification gauge coupling in these models are calculated and the
gauge boson mediated proton decay rates are estimated. In some cases the
predicted proton lifetime turns out to be in the border-line of experimental
limit. The predictions of the top quark mass, the mass ratio $m_b(m_b)/
m_\tau(m_\tau)$ from the two-loop evolution of Yukawa couplings and the mass of
the left handed neutrino via see-saw mechanism are summarized. The lower bounds
on the ratio of the VEVs of the two low energy doublets ($\tan\beta$) from the
requirement of the perturbative unitarity of the top quark Yukawa coupling up
to the grand unification scale are also presented. All the predictions have
been compared with those of the one-step unified theory.
| [
{
"created": "Sun, 25 Feb 1996 20:00:29 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Mar 1996 15:07:16 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Bastero-Gil",
"Mar",
"",
"SISSA"
],
[
"Brahmachari",
"Biswajoy",
"",
"ICTP"
]
] | Two-loop evolutions of the gauge couplings in a class of intermediate scale supersymmetric SO(10) models including the effect of third generation Yukawa couplings are studied. The unification scale, the intermediate scale and the value of the unification gauge coupling in these models are calculated and the gauge boson mediated proton decay rates are estimated. In some cases the predicted proton lifetime turns out to be in the border-line of experimental limit. The predictions of the top quark mass, the mass ratio $m_b(m_b)/ m_\tau(m_\tau)$ from the two-loop evolution of Yukawa couplings and the mass of the left handed neutrino via see-saw mechanism are summarized. The lower bounds on the ratio of the VEVs of the two low energy doublets ($\tan\beta$) from the requirement of the perturbative unitarity of the top quark Yukawa coupling up to the grand unification scale are also presented. All the predictions have been compared with those of the one-step unified theory. |
hep-ph/9511337 | Tim Tait | Ehab Malkawi and Tim Tait (Michigan State University) | Top-Charm Strong Flavor-Changing Neutral Currents at the Tevatron | 25 pages, 2 postscript figures using epsf.sty This replacement
includes the correction of a few errors which have small effects on the
results. It is the version to be published in Phys Rev D | Phys.Rev.D54:5758-5762,1996 | 10.1103/PhysRevD.54.5758 | MSUHEP-51116 | hep-ph | null | The possibility of an anomalous coupling between the top and charm quarks and
the gluon field is explored in a model-independent way using an effective
Lagrangian that is gauge-invariant under a non-linear realization of SU(3)$_{C}
\times$ SU(2$)_{L} \times$ U(1$)_{Y}$. Even for the current 200 $pb^{-1}$ of
integrated luminosity at the Tevatron, the new physics scale that strongly
modifies the coupling of t-c-g must be larger than about 2.5 TeV if no signal
is found within a 3$\sigma$ confidence limit. For 1 $fb^{-1}$ of data, this
constraint can be pushed up to 3.8 TeV.
| [
{
"created": "Thu, 16 Nov 1995 05:19:42 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Sep 1996 15:22:11 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Malkawi",
"Ehab",
"",
"Michigan State University"
],
[
"Tait",
"Tim",
"",
"Michigan State University"
]
] | The possibility of an anomalous coupling between the top and charm quarks and the gluon field is explored in a model-independent way using an effective Lagrangian that is gauge-invariant under a non-linear realization of SU(3)$_{C} \times$ SU(2$)_{L} \times$ U(1$)_{Y}$. Even for the current 200 $pb^{-1}$ of integrated luminosity at the Tevatron, the new physics scale that strongly modifies the coupling of t-c-g must be larger than about 2.5 TeV if no signal is found within a 3$\sigma$ confidence limit. For 1 $fb^{-1}$ of data, this constraint can be pushed up to 3.8 TeV. |
hep-ph/9802223 | Kumar Gupta | Debrupa Chakraverty, Triptesh De, Binayak Dutta-Roy and K. S. Gupta
(Saha Inst. of Nuclear Physics) | Dispersive Bounds on The Shape Of Lambda_b to Lambda_c l {\bar \nu_l}
Formfactors | 18 pages, 1 figure included via psfig | Int.J.Mod.Phys. A14 (1999) 2385-2396 | 10.1142/S0217751X99001196 | SINP-TNP/98-04 | hep-ph | null | We derive a theoretically allowed domain for the charge radius $\rho$ and
curvature $c$ of the Isgur-Wise function describing the decay $\Lambda_b \to
\Lambda_c l {\bar \nu_l}$. Our method uses crossing symmetry, dispersion
relations and analyticity in the context of the Heavy Quark Effective Theory
but is independent of the specifics of any given model. The experimentally
determined values of the $\Upsilon$ masses have been used as input information.
The results are of interest for testing different models employed to calculate
the heavy baryon formfactors which are used for the extraction of $| V_{cb} |$
from the experimental data.
| [
{
"created": "Tue, 3 Feb 1998 08:23:49 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Chakraverty",
"Debrupa",
"",
"Saha Inst. of Nuclear Physics"
],
[
"De",
"Triptesh",
"",
"Saha Inst. of Nuclear Physics"
],
[
"Dutta-Roy",
"Binayak",
"",
"Saha Inst. of Nuclear Physics"
],
[
"Gupta",
"K. S.",
"",
"Saha Inst. of Nuclear Ph... | We derive a theoretically allowed domain for the charge radius $\rho$ and curvature $c$ of the Isgur-Wise function describing the decay $\Lambda_b \to \Lambda_c l {\bar \nu_l}$. Our method uses crossing symmetry, dispersion relations and analyticity in the context of the Heavy Quark Effective Theory but is independent of the specifics of any given model. The experimentally determined values of the $\Upsilon$ masses have been used as input information. The results are of interest for testing different models employed to calculate the heavy baryon formfactors which are used for the extraction of $| V_{cb} |$ from the experimental data. |
1104.5123 | Tobias Hurth | Tobias Hurth | Interpretation of charged Higgs effects in low energy flavour physics | 14 pages, 16 figures | null | null | MZ-TH/11-06 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss two-Higgs-doublet models in view of the present flavour data, in
particular present indirect bounds and different techniques of flavour
protection
| [
{
"created": "Wed, 27 Apr 2011 12:33:09 GMT",
"version": "v1"
}
] | 2011-04-28 | [
[
"Hurth",
"Tobias",
""
]
] | We discuss two-Higgs-doublet models in view of the present flavour data, in particular present indirect bounds and different techniques of flavour protection |
1112.4501 | Guillaume Beuf | Guillaume Beuf | NLO corrections for the dipole factorization of DIS structure functions
at low x | 21 pages, 4 figures. Some corrections to the bibliography and to
Eq.(29) are done in the version 2 | Phys. Rev. D 85, 034039 (2012) | 10.1103/PhysRevD.85.034039 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The NLO generalization of the dipole factorization formula for the structure
functions F_2 and F_L at low x is calculated using light front perturbation
theory. That result gives some interesting insight into the kinematics of
initial state parton showers in mixed space.
| [
{
"created": "Mon, 19 Dec 2011 21:23:57 GMT",
"version": "v1"
},
{
"created": "Mon, 12 Mar 2012 15:58:11 GMT",
"version": "v2"
}
] | 2012-03-13 | [
[
"Beuf",
"Guillaume",
""
]
] | The NLO generalization of the dipole factorization formula for the structure functions F_2 and F_L at low x is calculated using light front perturbation theory. That result gives some interesting insight into the kinematics of initial state parton showers in mixed space. |
1010.1471 | Bhupal Dev | Steve Blanchet, P. S. Bhupal Dev, R. N. Mohapatra | Leptogenesis with TeV Scale Inverse Seesaw in SO(10) | References and a few comments added, improved figures; version to be
published in PRD | Phys.Rev.D82:115025,2010 | 10.1103/PhysRevD.82.115025 | UMD-PP-10-016, IFT-UAM/CSIC-10-53, FTUAM-10-14 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss leptogenesis within a TeV-scale inverse seesaw model for neutrino
masses where the seesaw structure is guaranteed by an SO(10) symmetry. Contrary
to the TeV-scale type-I gauged seesaw, the constraints imposed by successful
leptogenesis in these models are rather weak and allow for the extra gauge
bosons W_R and Z' to be in the LHC accessible range. The key differences in the
inverse seesaw compared to the type I case are: (i) decay and inverse decay
rates larger than the scatterings involving extra gauge bosons due to the large
Yukawa couplings and (ii) the suppression of the washout due to very small
lepton number breaking.
| [
{
"created": "Thu, 7 Oct 2010 16:14:02 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Dec 2010 15:07:07 GMT",
"version": "v2"
}
] | 2011-01-20 | [
[
"Blanchet",
"Steve",
""
],
[
"Dev",
"P. S. Bhupal",
""
],
[
"Mohapatra",
"R. N.",
""
]
] | We discuss leptogenesis within a TeV-scale inverse seesaw model for neutrino masses where the seesaw structure is guaranteed by an SO(10) symmetry. Contrary to the TeV-scale type-I gauged seesaw, the constraints imposed by successful leptogenesis in these models are rather weak and allow for the extra gauge bosons W_R and Z' to be in the LHC accessible range. The key differences in the inverse seesaw compared to the type I case are: (i) decay and inverse decay rates larger than the scatterings involving extra gauge bosons due to the large Yukawa couplings and (ii) the suppression of the washout due to very small lepton number breaking. |
1107.3970 | He Zhang | Werner Rodejohann, He Zhang, Shun Zhou | Systematic search for successful lepton mixing patterns with nonzero
theta_13 | 10 pages, 4 figures, 2 tables; version to be published in Nuclear
Physics B | null | 10.1016/j.nuclphysb.2011.10.017 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a systematic search for simple but viable lepton mixing patterns.
Our main criterion is that the mixing matrix can be parameterized by three
rotation angles, which are simple fractions of pi. These simple rotation angles
possess exact expressions for their sines and cosines, and often arise in the
flavor symmetry models. All possible parameterizations of the mixing matrix are
taken into account. In total, twenty successful mixing patterns are found to be
consistent with the latest neutrino oscillation data (including the recent T2K
results) in the CP conserving case, whereas fifteen mixing patterns are allowed
in the maximal CP violating case. Potential radiative corrections to the
constant mixing patterns are also calculated by solving the renormalization
group equations.
| [
{
"created": "Wed, 20 Jul 2011 13:24:49 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Oct 2011 16:32:47 GMT",
"version": "v2"
}
] | 2015-05-28 | [
[
"Rodejohann",
"Werner",
""
],
[
"Zhang",
"He",
""
],
[
"Zhou",
"Shun",
""
]
] | We perform a systematic search for simple but viable lepton mixing patterns. Our main criterion is that the mixing matrix can be parameterized by three rotation angles, which are simple fractions of pi. These simple rotation angles possess exact expressions for their sines and cosines, and often arise in the flavor symmetry models. All possible parameterizations of the mixing matrix are taken into account. In total, twenty successful mixing patterns are found to be consistent with the latest neutrino oscillation data (including the recent T2K results) in the CP conserving case, whereas fifteen mixing patterns are allowed in the maximal CP violating case. Potential radiative corrections to the constant mixing patterns are also calculated by solving the renormalization group equations. |
hep-ph/9801292 | Nils Hammon | N. Hammon, A. Dumitru, H. Stoecker, W. Greiner | Nuclear Shadowing Effects on Prompt Photons at RHIC and LHC | 15 pages, Latex, 10 eps-figures | Phys.Rev.C57:3292-3298,1998 | 10.1103/PhysRevC.57.3292 | null | hep-ph nucl-th | null | The transverse momentum distribution of prompt photons coming from the very
early phase of ultrarelativistic heavy ion collisions for the RHIC and LHC
energies is calculated by means of perturbative QCD. We calculate the single
photon cross section ($A+B\to \gamma +X$) by taking into account the partonic
sub processes $q+ \bar{q}\to \gamma +g$ and $q+g\to\gamma +q$ as well as the
Bremsstrahlung corrections to those processes. We choose a lower momentum
cut-off $k_0 =2$ GeV separating the soft physics from perturbative QCD. We
compare the results for those primary collision with the photons produced in
reactions of the thermalized secondary particles, which are calculated within
scaling hydrodynamics. The QCD processes are taken in leading order. Nuclear
shadowing corrections, which alter the involved nuclear structure functions are
explicitly taken into account and compared to unshadowed results. Employing the
GRV parton distribution parametrizations we find that at RHIC prompt
QCD-photons dominate over the thermal radiation down to transverse momenta $k_T
\approx 2$ GeV. At LHC, however, thermal radiation from the QGP dominates for
photon transverse momenta $k_T \leq 5$ GeV, if nuclear shadowing effects on
prompt photon production are taken into account.
| [
{
"created": "Wed, 14 Jan 1998 10:32:28 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Hammon",
"N.",
""
],
[
"Dumitru",
"A.",
""
],
[
"Stoecker",
"H.",
""
],
[
"Greiner",
"W.",
""
]
] | The transverse momentum distribution of prompt photons coming from the very early phase of ultrarelativistic heavy ion collisions for the RHIC and LHC energies is calculated by means of perturbative QCD. We calculate the single photon cross section ($A+B\to \gamma +X$) by taking into account the partonic sub processes $q+ \bar{q}\to \gamma +g$ and $q+g\to\gamma +q$ as well as the Bremsstrahlung corrections to those processes. We choose a lower momentum cut-off $k_0 =2$ GeV separating the soft physics from perturbative QCD. We compare the results for those primary collision with the photons produced in reactions of the thermalized secondary particles, which are calculated within scaling hydrodynamics. The QCD processes are taken in leading order. Nuclear shadowing corrections, which alter the involved nuclear structure functions are explicitly taken into account and compared to unshadowed results. Employing the GRV parton distribution parametrizations we find that at RHIC prompt QCD-photons dominate over the thermal radiation down to transverse momenta $k_T \approx 2$ GeV. At LHC, however, thermal radiation from the QGP dominates for photon transverse momenta $k_T \leq 5$ GeV, if nuclear shadowing effects on prompt photon production are taken into account. |
1906.10821 | Markos Maniatis | M. Maniatis | Application of BCFW-recursion relations and the Feynman-tree theorem to
the four gluon amplitude with all plus helicities | 9 pages | Phys. Rev. D 100, 096022 (2019) | 10.1103/PhysRevD.100.096022 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently it has been shown that in gauge theories amplitudes to any
perturbation order can be obtained by glueing together simple three-point
on-shell amplitudes. These three-point amplitudes in turn are fixed by locality
and Lorentz invariance. This factorization into three-point on-shell amplitudes
follows from the BCFW recursion relations and the Feynman-tree theorem. In an
explicit example, that is, the four-gluon amplitude with all plus helicities,
we illustrate the method. In conventional calculation this amplitude
corresponds to one-loop box diagrams.
| [
{
"created": "Wed, 26 Jun 2019 02:54:10 GMT",
"version": "v1"
}
] | 2019-12-04 | [
[
"Maniatis",
"M.",
""
]
] | Recently it has been shown that in gauge theories amplitudes to any perturbation order can be obtained by glueing together simple three-point on-shell amplitudes. These three-point amplitudes in turn are fixed by locality and Lorentz invariance. This factorization into three-point on-shell amplitudes follows from the BCFW recursion relations and the Feynman-tree theorem. In an explicit example, that is, the four-gluon amplitude with all plus helicities, we illustrate the method. In conventional calculation this amplitude corresponds to one-loop box diagrams. |
2106.15371 | Miguel \'Angel Escobedo Espinosa | Jean-Paul Blaizot and Miguel \'Angel Escobedo | Phenomenological study of quarkonium suppression and the impact of the
energy gap between singlets and octets | Published version. 25 pages, 11 figures | Phys. Rev. D 104, 054034 (2021) | 10.1103/PhysRevD.104.054034 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The study of heavy quarkonium suppression in heavy-ion collisions represents
an important source of information about the properties of the quark-gluon
plasma produced in such collisions. In a previous paper, we have considered how
to model the evolution of a quarkonium in such a way that the solution of the
resulting equations evolves toward the correct thermal equilibrium distribution
for an homogeneous and static medium. We found that it is crucial to take into
account the energy gap between singlet and octet configurations when the
temperature is not much greater than this energy gap. In this manuscript, we
explore in more detail the phenomenological consequences of this observation in
the more realistic situation of an expanding system. We consider two different
scenarios, based on the same approximation scheme, but on different choices of
parameters. In the first case, we rely on a Hard Thermal Loop approximation,
while the second case is based on a recent determination of the static
potential in lattice QCD. In both cases, we compute the decay width and the
nuclear modification factor, both taking the energy gap into account and
ignoring it. We find that the impact on the predictions is as large in the
expanding medium as it is in the static case. Our conclusion is that this
energy gap should be taken into account in phenomenological studies.
| [
{
"created": "Tue, 29 Jun 2021 12:56:09 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Oct 2021 13:51:19 GMT",
"version": "v2"
}
] | 2021-10-04 | [
[
"Blaizot",
"Jean-Paul",
""
],
[
"Escobedo",
"Miguel Ángel",
""
]
] | The study of heavy quarkonium suppression in heavy-ion collisions represents an important source of information about the properties of the quark-gluon plasma produced in such collisions. In a previous paper, we have considered how to model the evolution of a quarkonium in such a way that the solution of the resulting equations evolves toward the correct thermal equilibrium distribution for an homogeneous and static medium. We found that it is crucial to take into account the energy gap between singlet and octet configurations when the temperature is not much greater than this energy gap. In this manuscript, we explore in more detail the phenomenological consequences of this observation in the more realistic situation of an expanding system. We consider two different scenarios, based on the same approximation scheme, but on different choices of parameters. In the first case, we rely on a Hard Thermal Loop approximation, while the second case is based on a recent determination of the static potential in lattice QCD. In both cases, we compute the decay width and the nuclear modification factor, both taking the energy gap into account and ignoring it. We find that the impact on the predictions is as large in the expanding medium as it is in the static case. Our conclusion is that this energy gap should be taken into account in phenomenological studies. |
hep-ph/0103304 | Alexey Gulov | A. V. Gulov and V. V. Skalozub | Renormalizability and searching for Z' gauge bosons | 5 pages, 4 figures | Nucl.Phys.Proc.Suppl. 102 (2001) 363-368 | 10.1016/S0920-5632(01)01580-8 | null | hep-ph | null | New observables for searching for Z' virtual states in processes
e^+e^-\to\bar{f}f are proposed. They are based on the relations following due
to renormalizability of an underlying theory between the parameters of the
low-energy effective Lagrangian. Two types of the Z' interactions are
considered. The observables allow to pick up uniquely the signals of both Z'
bosons. The search for the Z' at future linear colliders and the treating of
the LEP data are discussed.
| [
{
"created": "Wed, 28 Mar 2001 23:10:40 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Gulov",
"A. V.",
""
],
[
"Skalozub",
"V. V.",
""
]
] | New observables for searching for Z' virtual states in processes e^+e^-\to\bar{f}f are proposed. They are based on the relations following due to renormalizability of an underlying theory between the parameters of the low-energy effective Lagrangian. Two types of the Z' interactions are considered. The observables allow to pick up uniquely the signals of both Z' bosons. The search for the Z' at future linear colliders and the treating of the LEP data are discussed. |
1110.4268 | Partha Pratim Bhaduri | Partha Pratim Bhaduri, A. K. Chaudhuri and Subhasis Chattopadhyay | J/Psi production in proton induced collisions at FAIR | 17 pages, 37 figures. To appear in Physical Review C | null | 10.1103/PhysRevC.84.054914 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have examined the production of J/$\psi$ mesons in high energy
proton-proton and proton-nucleus collisions at beam energies in the range from
158 GeV to 920 GeV, available from different fixed target experiments. In the
employed model J/$\psi$ production in hadronic collisions is assumed to be a
factorisable two step process: (i) production of a $c\bar{c}$ pair which can be
reliably described by perturbative QCD, and (ii) formation of J/$\psi$
resonance from the $c\bar{c}$ pair, which can be conveniently parameterized
incorporating different existing physical mechanisms of color neutralization.
We show that, for lower collision energies, J/$\psi$ production through
quark-anti-quark annihilation gives larger contribution at higher $x_F$, while
gluon-gluon fusion dominates the production at smaller $x_F$. For
proton-nucleus collisions the model takes into account both the initial state
modification of parton distributions in nuclei and the final state interaction
of the produced $c\bar{c}$ pairs with the target nucleons. The model is found
to give reasonable description of data on J/$\psi$ production in protonic and
proton-nucleus collisions, for different existing fixed target experiments. In
case of proton-nucleus collisions, our calculations show a non-negligible
dependence of the final state nuclear dissociation of J/$\psi$ mesons on the
energy of the incident proton beam. The model has been applied to predict the
J/$\psi$ production and suppression expected in proton-nucleus collisions at
energies relevant to FAIR, the upcoming accelerator facility at Darmstadt,
Germany. The amount of suppressions, for different mechanisms of J/$\psi$
hadronization has been found to be distinguishably different which might help
an experimental settlement of the much controversial issue of color
neutralization.
| [
{
"created": "Wed, 19 Oct 2011 12:57:37 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Bhaduri",
"Partha Pratim",
""
],
[
"Chaudhuri",
"A. K.",
""
],
[
"Chattopadhyay",
"Subhasis",
""
]
] | We have examined the production of J/$\psi$ mesons in high energy proton-proton and proton-nucleus collisions at beam energies in the range from 158 GeV to 920 GeV, available from different fixed target experiments. In the employed model J/$\psi$ production in hadronic collisions is assumed to be a factorisable two step process: (i) production of a $c\bar{c}$ pair which can be reliably described by perturbative QCD, and (ii) formation of J/$\psi$ resonance from the $c\bar{c}$ pair, which can be conveniently parameterized incorporating different existing physical mechanisms of color neutralization. We show that, for lower collision energies, J/$\psi$ production through quark-anti-quark annihilation gives larger contribution at higher $x_F$, while gluon-gluon fusion dominates the production at smaller $x_F$. For proton-nucleus collisions the model takes into account both the initial state modification of parton distributions in nuclei and the final state interaction of the produced $c\bar{c}$ pairs with the target nucleons. The model is found to give reasonable description of data on J/$\psi$ production in protonic and proton-nucleus collisions, for different existing fixed target experiments. In case of proton-nucleus collisions, our calculations show a non-negligible dependence of the final state nuclear dissociation of J/$\psi$ mesons on the energy of the incident proton beam. The model has been applied to predict the J/$\psi$ production and suppression expected in proton-nucleus collisions at energies relevant to FAIR, the upcoming accelerator facility at Darmstadt, Germany. The amount of suppressions, for different mechanisms of J/$\psi$ hadronization has been found to be distinguishably different which might help an experimental settlement of the much controversial issue of color neutralization. |
hep-ph/0104033 | Edmond Iancu | J.-P. Blaizot, E. Iancu, and A. Rebhan | The thermodynamics of the quark-gluon plasma: Self-consistent
resummations vs. lattice data | 4 pages LaTeX2e, contribution to the proceedings of the 15th
International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions (QM
2001), Long Island, New York, January 15 - 20, 2001 | Nucl.Phys. A698 (2002) 404-407 | 10.1016/S0375-9474(01)01390-2 | Saclay-T01/038, TUW-01-09 | hep-ph | null | We discuss a recent approach for overcoming the poor convergence of the
perturbative expansion for the thermodynamic potential of QCD. This approach is
based on self-consistent approximations which allow for a gauge-invariant and
manifestly ultraviolet-finite resummation of the essential physics of the hard
thermal/dense loops. The results thus obtained are in good agreement with
available lattice data down to temperatures of about twice the critical
temperature. Calculations for a plasma with finite quark density (i.e., with a
non-zero chemical potential $\mu$) are no more difficult than at $\mu=0$.
| [
{
"created": "Tue, 3 Apr 2001 14:08:07 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Blaizot",
"J. -P.",
""
],
[
"Iancu",
"E.",
""
],
[
"Rebhan",
"A.",
""
]
] | We discuss a recent approach for overcoming the poor convergence of the perturbative expansion for the thermodynamic potential of QCD. This approach is based on self-consistent approximations which allow for a gauge-invariant and manifestly ultraviolet-finite resummation of the essential physics of the hard thermal/dense loops. The results thus obtained are in good agreement with available lattice data down to temperatures of about twice the critical temperature. Calculations for a plasma with finite quark density (i.e., with a non-zero chemical potential $\mu$) are no more difficult than at $\mu=0$. |
2012.03733 | Yong-Liang Ma | Qing-Sen Chen, Hui-Feng Fu, Yong-Liang Ma and Qing Wang | Chiral effective Lagrangian for heavy-light mesons from QCD: $1/m_{Q}$
correction | 10 pages | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | As a successive work to [Phys.Rev.D 102 (2020), 034034], we derive the
$1/m_Q$ corrections to chiral effective Lagrangian for heavy-light mesons from
QCD under proper approximations. The low energy constants in the effective
Lagrangian are expressed in terms of the light quark self-energy and heavy
quark mass $m_Q$. Numerical results of the low energy constants with $1/m_Q$
corrections are given. We find that the results of pion decay constant and the
masses of heavy-light mesons are improved coherently compared to that obtained
in the heavy quark limit.
| [
{
"created": "Mon, 7 Dec 2020 14:32:52 GMT",
"version": "v1"
}
] | 2020-12-08 | [
[
"Chen",
"Qing-Sen",
""
],
[
"Fu",
"Hui-Feng",
""
],
[
"Ma",
"Yong-Liang",
""
],
[
"Wang",
"Qing",
""
]
] | As a successive work to [Phys.Rev.D 102 (2020), 034034], we derive the $1/m_Q$ corrections to chiral effective Lagrangian for heavy-light mesons from QCD under proper approximations. The low energy constants in the effective Lagrangian are expressed in terms of the light quark self-energy and heavy quark mass $m_Q$. Numerical results of the low energy constants with $1/m_Q$ corrections are given. We find that the results of pion decay constant and the masses of heavy-light mesons are improved coherently compared to that obtained in the heavy quark limit. |
hep-ph/9810449 | Asmaa Abada | A. Abada, O. Pene and J. Rodriguez-Quintero | Addendum to Finite-size effects on multibody neutrino exchange | Latex file (Revtex), 9 pages, 1 figure, one reference changed | Phys. Rev. D 59, 077302 (1999) | 10.1103/PhysRevD.59.077302 | CERN-TH/98-309, FAMNSE-98/37, LPTHE Orsay-98/60 | hep-ph | null | The interaction energy of the neutrons due to massless neutrino exchange in a
neutron star has recently been proved, using an effective theory, to be
extremely small and infrared-safe. Our comment here is of conceptual order: two
approaches to compute the total interaction energy density have recently been
proposed. Here, we study the connection between these two approaches. From CP
invariance, we argue that the resulting interaction energy has to be even in
the parameter $b=-G_F n_n /\sqrt{2}$, which expresses the static neutrino
potential created by a neutron medium of density $n_n$.
| [
{
"created": "Thu, 22 Oct 1998 10:12:03 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Oct 1998 14:26:24 GMT",
"version": "v2"
}
] | 2016-08-25 | [
[
"Abada",
"A.",
""
],
[
"Pene",
"O.",
""
],
[
"Rodriguez-Quintero",
"J.",
""
]
] | The interaction energy of the neutrons due to massless neutrino exchange in a neutron star has recently been proved, using an effective theory, to be extremely small and infrared-safe. Our comment here is of conceptual order: two approaches to compute the total interaction energy density have recently been proposed. Here, we study the connection between these two approaches. From CP invariance, we argue that the resulting interaction energy has to be even in the parameter $b=-G_F n_n /\sqrt{2}$, which expresses the static neutrino potential created by a neutron medium of density $n_n$. |
1409.4339 | Yutaka Tobita | Kenzo Ishikawa, Toshiki Tajima, and Yutaka Tobita | Anomalous radiative transitions | 47 pages, 5 figures, 1 table, typos corrected | null | 10.1093/ptep/ptu168 | EPHOU-14-016 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Anomalous transitions involving photons derived by many-body interaction of
the form, $\partial_{\mu} G^{\mu}$, in the standard model are studied. This
does not affect the equation of motion in the bulk, but makes wave functions
modified, and causes the unusual transition characterized by the
time-independent probability. In the transition probability at a time-interval
$T$ expressed generally in the form $P=T \Gamma_0 +P^{(d)}$, now with $ P^{(d)}
\neq 0 $. The diffractive term $P^{(d)}$ has the origin in the overlap of waves
of the initial and final states, and reveals the characteristics of waves. In
particular, the processes of the neutrino-photon interaction ordinarily
forbidden by Landau-Yang's theorem ($\Gamma_0=0$) manifests itself through the
boundary interaction. The new term leads to physical processes over a wide
energy range to have finite probabilities. New methods of detecting neutrinos
using laser are proposed that are based on this difractive term, which enhance
the detectability of neutrinos by many orders of magnitude.
| [
{
"created": "Mon, 15 Sep 2014 17:23:42 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Sep 2014 09:31:13 GMT",
"version": "v2"
},
{
"created": "Tue, 30 Sep 2014 04:12:11 GMT",
"version": "v3"
}
] | 2014-12-31 | [
[
"Ishikawa",
"Kenzo",
""
],
[
"Tajima",
"Toshiki",
""
],
[
"Tobita",
"Yutaka",
""
]
] | Anomalous transitions involving photons derived by many-body interaction of the form, $\partial_{\mu} G^{\mu}$, in the standard model are studied. This does not affect the equation of motion in the bulk, but makes wave functions modified, and causes the unusual transition characterized by the time-independent probability. In the transition probability at a time-interval $T$ expressed generally in the form $P=T \Gamma_0 +P^{(d)}$, now with $ P^{(d)} \neq 0 $. The diffractive term $P^{(d)}$ has the origin in the overlap of waves of the initial and final states, and reveals the characteristics of waves. In particular, the processes of the neutrino-photon interaction ordinarily forbidden by Landau-Yang's theorem ($\Gamma_0=0$) manifests itself through the boundary interaction. The new term leads to physical processes over a wide energy range to have finite probabilities. New methods of detecting neutrinos using laser are proposed that are based on this difractive term, which enhance the detectability of neutrinos by many orders of magnitude. |
hep-ph/0206293 | Michelangelo Mangano | M.L. Mangano, M. Moretti, F. Piccinini, R. Pittau and A.D. Polosa | ALPGEN, a generator for hard multiparton processes in hadronic
collisions | 1+38 pages, uses JHEP.cls. Documents code version 1.2: extended list
of processes, updated documentation and bibliography | JHEP 0307 (2003) 001 | 10.1088/1126-6708/2003/07/001 | CERN-TH/2002-129 | hep-ph | null | This paper presents a new event generator, ALPGEN, dedicated to the study of
multiparton hard processes in hadronic collisions. The code performs, at the
leading order in QCD and EW interactions, the calculation of the exact matrix
elements for a large set of parton-level processes of interest in the study of
the Tevatron and LHC data. The current version of the code describes the
following final states: (W -> ffbar') QQbar+ N jets (Q being a heavy quark, and
f=l,q), with N<=4; (Z/gamma* -> f fbar)+QQbar+Njets (f=l,nu), with N<=4; (W ->
ffbar') + charm + N jets (f=l,q), N<= 5; (W -> f fbar') + N jets (f=l,q) and
(Z/gamma* -> f fbar)+ N jets (f=l,nu), with N<=6; nW+mZ+lH+N jets, with
n+m+l+N<=8 and N<=3 including all 2-fermion decay modes of W and Z bosons, with
spin correlations; Q Qbar+N jets (N<=6) with t -> b f fbar' decays and relative
spin correlations included if Q=t; Q Qbar Q' Qbar'+N jets, with Q and Q' heavy
quarks (possibly equal) and N<=4; H Q Qbar+N jets (N<=4) with t -> b f fbar'
decays and relative spin correlations included if Q=t; N jets, with N<=6.
Parton-level events are generated, providing full information on their colour
and flavour structure, enabling the evolution of the partons into fully
hadronised final states.
| [
{
"created": "Fri, 28 Jun 2002 17:40:08 GMT",
"version": "v1"
},
{
"created": "Mon, 26 May 2003 15:13:24 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Mangano",
"M. L.",
""
],
[
"Moretti",
"M.",
""
],
[
"Piccinini",
"F.",
""
],
[
"Pittau",
"R.",
""
],
[
"Polosa",
"A. D.",
""
]
] | This paper presents a new event generator, ALPGEN, dedicated to the study of multiparton hard processes in hadronic collisions. The code performs, at the leading order in QCD and EW interactions, the calculation of the exact matrix elements for a large set of parton-level processes of interest in the study of the Tevatron and LHC data. The current version of the code describes the following final states: (W -> ffbar') QQbar+ N jets (Q being a heavy quark, and f=l,q), with N<=4; (Z/gamma* -> f fbar)+QQbar+Njets (f=l,nu), with N<=4; (W -> ffbar') + charm + N jets (f=l,q), N<= 5; (W -> f fbar') + N jets (f=l,q) and (Z/gamma* -> f fbar)+ N jets (f=l,nu), with N<=6; nW+mZ+lH+N jets, with n+m+l+N<=8 and N<=3 including all 2-fermion decay modes of W and Z bosons, with spin correlations; Q Qbar+N jets (N<=6) with t -> b f fbar' decays and relative spin correlations included if Q=t; Q Qbar Q' Qbar'+N jets, with Q and Q' heavy quarks (possibly equal) and N<=4; H Q Qbar+N jets (N<=4) with t -> b f fbar' decays and relative spin correlations included if Q=t; N jets, with N<=6. Parton-level events are generated, providing full information on their colour and flavour structure, enabling the evolution of the partons into fully hadronised final states. |
1311.6386 | Ranjan Laha | Ranjan Laha, Eric Braaten | Direct detection of dark matter in universal bound states | v2: 14 pages, 5 figures. Added discussion on survival of bound state
dark matter and bound state dark matter self-scattering. Conclusions
unchanged. Journal version | Phys. Rev. D 89, 103510 (2014) | 10.1103/PhysRevD.89.103510 | null | hep-ph astro-ph.CO astro-ph.GA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the signatures for internal structure of dark matter in direct
detection experiments in the context of asymmetric self-interacting dark
matter. The self-interaction cross section of two dark matter particles at low
energies is assumed to come close to saturating the S-wave unitarity bound,
which requires the presence of a resonance near their scattering threshold. The
universality of S-wave near-threshold resonances then implies that the
low-energy scattering properties of a two-body bound state of dark matter
particles are completely determined by its binding energy, irrespective of the
underlying microphysics. The form factor for elastic scattering of the bound
state from a nucleus and the possibility of breakup of the bound state produce
new signatures in the nuclear recoil energy spectrum. If these features are
observed in experiments, it will give a smoking-gun signature for the internal
structure of dark matter.
| [
{
"created": "Mon, 25 Nov 2013 18:07:13 GMT",
"version": "v1"
},
{
"created": "Sat, 10 May 2014 16:13:51 GMT",
"version": "v2"
}
] | 2014-05-13 | [
[
"Laha",
"Ranjan",
""
],
[
"Braaten",
"Eric",
""
]
] | We study the signatures for internal structure of dark matter in direct detection experiments in the context of asymmetric self-interacting dark matter. The self-interaction cross section of two dark matter particles at low energies is assumed to come close to saturating the S-wave unitarity bound, which requires the presence of a resonance near their scattering threshold. The universality of S-wave near-threshold resonances then implies that the low-energy scattering properties of a two-body bound state of dark matter particles are completely determined by its binding energy, irrespective of the underlying microphysics. The form factor for elastic scattering of the bound state from a nucleus and the possibility of breakup of the bound state produce new signatures in the nuclear recoil energy spectrum. If these features are observed in experiments, it will give a smoking-gun signature for the internal structure of dark matter. |
2312.05370 | Eric S. Swanson | C. Farina and E.S. Swanson | A Constituent Model of Light Hybrid Meson Decays | 30 pages, 8 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by-nc-sa/4.0/ | A model of light hybrid mesons and their strong decays is developed. The
model employs a gluonic quasiparticle to describe low energy gluodynamics and
uses the QCD Hamiltonian in Coulomb gauge to guide the construction of states
and decay amplitudes. We compute the partial widths of the twelve low lying
isovector and vector hybrids. Implications of these results on hybrid searches
are also made, with the chief conclusions being that direct observation of the
vector states will be difficult, that a hybrid $\pi(1800)$ has distinctive
decay characteristics, a narrow $\eta(1900)$ hybrid should exist, an
$\eta_1(1750)$ should be sought, and that the exotic nature of $J^{PC}= 2^{-+}$
hybrid mesons should be discernible with sufficient data. We argue that the
isovector $\pi_2$ hybrid has been discovered, giving a total of four possible
hybrid mesons, $\pi_1(1600)$, $\eta_1(1855)$, $\pi(1800)$, and $\pi_2(2360)$,
which appear to be filling out the lowlying hybrid supermultiplet in the
expected fashion.
| [
{
"created": "Fri, 8 Dec 2023 21:14:50 GMT",
"version": "v1"
}
] | 2023-12-12 | [
[
"Farina",
"C.",
""
],
[
"Swanson",
"E. S.",
""
]
] | A model of light hybrid mesons and their strong decays is developed. The model employs a gluonic quasiparticle to describe low energy gluodynamics and uses the QCD Hamiltonian in Coulomb gauge to guide the construction of states and decay amplitudes. We compute the partial widths of the twelve low lying isovector and vector hybrids. Implications of these results on hybrid searches are also made, with the chief conclusions being that direct observation of the vector states will be difficult, that a hybrid $\pi(1800)$ has distinctive decay characteristics, a narrow $\eta(1900)$ hybrid should exist, an $\eta_1(1750)$ should be sought, and that the exotic nature of $J^{PC}= 2^{-+}$ hybrid mesons should be discernible with sufficient data. We argue that the isovector $\pi_2$ hybrid has been discovered, giving a total of four possible hybrid mesons, $\pi_1(1600)$, $\eta_1(1855)$, $\pi(1800)$, and $\pi_2(2360)$, which appear to be filling out the lowlying hybrid supermultiplet in the expected fashion. |
hep-ph/0509153 | Ikaros Bigi | I.I. Bigi | Hadronization -- the Unsung Hero rather than the Alleged Villain in the
Tale of CP Violation | 15 pages, no figures; Invited Talk given at Hadron 05, Rio de
Janeiro, August 22 - 26, 2005 | null | 10.1063/1.2176486 | UND-HEP-05-BIG04 | hep-ph | null | The novel successes scored by the Standard Model of High Energy Physics in
the last few years concerning heavy flavour dynamics do not weaken the case for
`New Physics' around the TeV scale. They do suggest however that one cannot
{\em count} on that New Physics impacting heavy flavour decays in a numerically
massive way. Yet studying this impact will be essential in diagnosing the
features of the New Physics. In particular the decays of beauty hadrons have to
be analyzed with considerable precision on the experimental as well as
theoretical side. While hadronization effects often represent the main
bottleneck in our understanding in the short run, they will provide powerful
and discriminating tools in the long run, when applied comprehensively and
judiciously. The expertise required to exhaust the discovery potential in $B$
decays does exist in the hadron physics community or can be developed without
needing a new breakthrough -- yet a greater effort has to be made to
communicate it to the heavy flavour community.
| [
{
"created": "Wed, 14 Sep 2005 20:40:25 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Bigi",
"I. I.",
""
]
] | The novel successes scored by the Standard Model of High Energy Physics in the last few years concerning heavy flavour dynamics do not weaken the case for `New Physics' around the TeV scale. They do suggest however that one cannot {\em count} on that New Physics impacting heavy flavour decays in a numerically massive way. Yet studying this impact will be essential in diagnosing the features of the New Physics. In particular the decays of beauty hadrons have to be analyzed with considerable precision on the experimental as well as theoretical side. While hadronization effects often represent the main bottleneck in our understanding in the short run, they will provide powerful and discriminating tools in the long run, when applied comprehensively and judiciously. The expertise required to exhaust the discovery potential in $B$ decays does exist in the hadron physics community or can be developed without needing a new breakthrough -- yet a greater effort has to be made to communicate it to the heavy flavour community. |
2308.02808 | Yu Seon Jeong | Yu Seon Jeong, Weidong Bai, Milind Diwan, Maria Vittoria Garzelli,
Karan Kumar and Mary Hall Reno | Forward production of prompt neutrinos in the atmosphere and at
high-energy colliders | 8 pages, 4 figures, a proceeding for ICRC 2023 | null | null | null | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | The atmospheric neutrino flux at very high energies is dominated by prompt
neutrinos, mostly contributed by the decays of charmed hadrons produced in the
forward direction by cosmic ray interactions with air nuclei. Theoretical
predictions of the prompt atmospheric neutrino flux have large uncertainties
mainly related to charm hadron production. Prompt neutrinos can also be studied
through high-energy colliders. In particular, two ongoing forward experiments
and the proposed Forward Physics Facility at the LHC can detect forward prompt
neutrinos. We will present the kinematic regions relevant to the prompt
atmospheric neutrino flux in terms of collider kinematic variables, the
collision energy $\sqrt{s}$ and the center-of-mass rapidity of charm hadrons
$y$, and discuss implications of the forward experiments at the LHC on the
theoretical predictions of the prompt atmospheric neutrino flux.
| [
{
"created": "Sat, 5 Aug 2023 06:47:28 GMT",
"version": "v1"
}
] | 2023-08-08 | [
[
"Jeong",
"Yu Seon",
""
],
[
"Bai",
"Weidong",
""
],
[
"Diwan",
"Milind",
""
],
[
"Garzelli",
"Maria Vittoria",
""
],
[
"Kumar",
"Karan",
""
],
[
"Reno",
"Mary Hall",
""
]
] | The atmospheric neutrino flux at very high energies is dominated by prompt neutrinos, mostly contributed by the decays of charmed hadrons produced in the forward direction by cosmic ray interactions with air nuclei. Theoretical predictions of the prompt atmospheric neutrino flux have large uncertainties mainly related to charm hadron production. Prompt neutrinos can also be studied through high-energy colliders. In particular, two ongoing forward experiments and the proposed Forward Physics Facility at the LHC can detect forward prompt neutrinos. We will present the kinematic regions relevant to the prompt atmospheric neutrino flux in terms of collider kinematic variables, the collision energy $\sqrt{s}$ and the center-of-mass rapidity of charm hadrons $y$, and discuss implications of the forward experiments at the LHC on the theoretical predictions of the prompt atmospheric neutrino flux. |
0706.2332 | Marco Picariello | Marco Picariello, Bhag C. Chauhan, Joao Pulido, Emilio Torrente-Lujan | Predictions from non trivial Quark-Lepton complementarity | 15 pages, 5 figures, ws-ijmpa class included, Proceedings of the CTP
Symposium on Sypersymmetry at LHC | Int.J.Mod.Phys.A22:5860-5874,2007 | 10.1142/S0217751X07039080 | null | hep-ph | null | The complementarity between the quark and lepton mixing matrices is shown to
provide robust predictions. We obtain these predictions by first showing that
the matrix V_M, product of the quark (CKM) and lepton (PMNS) mixing matrices,
may have a zero (1,3) entry which is favored by experimental data.
We obtain that any theoretical model with a vanishing (1,3) entry of V_M that
is in agreement with quark data, solar, and atmospheric mixing angle leads to
$\theta_{13}^{PMNS}=(9{^{+1}_{-2}})^\circ$. This value is consistent with the
present 90% CL experimental upper limit. We also investigate the prediction on
the lepton phases. We show that the actual evidence, under the only assumption
that the correlation matrix V_M product of CKM and PMNS has a zero in the entry
(1,3), gives us a prediction for the three CP-violating invariants J, S_1, and
S_2. A better determination of the lepton mixing angles will give stronger
prediction for the CP-violating invariants in the lepton sector. These will be
tested in the next generation experiments. Finally we compute the effect of non
diagonal neutrino mass in "l_i -> l_j gamma" in SUSY theories with non trivial
Quark-Lepton complementarity and a flavor symmetry. The Quark-Lepton
complementarity and the flavor symmetry strongly constrain the theory and we
obtain a clear prediction for the contribution to "mu -> e gamma" and the "tau"
decays "tau -> e gamma" and "tau -> mu gamma". If the Dirac neutrino Yukawa
couplings are degenerate but the low energy neutrino masses are not degenerate,
then the lepton decays are related among them by the V_M entries. On the other
hand, if the Dirac neutrino Yukawa couplings are hierarchical or the low energy
neutrino masses are degenerate, then the prediction for the lepton decays comes
from the CKM hierarchy.
| [
{
"created": "Fri, 15 Jun 2007 17:00:58 GMT",
"version": "v1"
}
] | 2009-06-11 | [
[
"Picariello",
"Marco",
""
],
[
"Chauhan",
"Bhag C.",
""
],
[
"Pulido",
"Joao",
""
],
[
"Torrente-Lujan",
"Emilio",
""
]
] | The complementarity between the quark and lepton mixing matrices is shown to provide robust predictions. We obtain these predictions by first showing that the matrix V_M, product of the quark (CKM) and lepton (PMNS) mixing matrices, may have a zero (1,3) entry which is favored by experimental data. We obtain that any theoretical model with a vanishing (1,3) entry of V_M that is in agreement with quark data, solar, and atmospheric mixing angle leads to $\theta_{13}^{PMNS}=(9{^{+1}_{-2}})^\circ$. This value is consistent with the present 90% CL experimental upper limit. We also investigate the prediction on the lepton phases. We show that the actual evidence, under the only assumption that the correlation matrix V_M product of CKM and PMNS has a zero in the entry (1,3), gives us a prediction for the three CP-violating invariants J, S_1, and S_2. A better determination of the lepton mixing angles will give stronger prediction for the CP-violating invariants in the lepton sector. These will be tested in the next generation experiments. Finally we compute the effect of non diagonal neutrino mass in "l_i -> l_j gamma" in SUSY theories with non trivial Quark-Lepton complementarity and a flavor symmetry. The Quark-Lepton complementarity and the flavor symmetry strongly constrain the theory and we obtain a clear prediction for the contribution to "mu -> e gamma" and the "tau" decays "tau -> e gamma" and "tau -> mu gamma". If the Dirac neutrino Yukawa couplings are degenerate but the low energy neutrino masses are not degenerate, then the lepton decays are related among them by the V_M entries. On the other hand, if the Dirac neutrino Yukawa couplings are hierarchical or the low energy neutrino masses are degenerate, then the prediction for the lepton decays comes from the CKM hierarchy. |
2010.15712 | Diego Aristizabal | D. Aristizabal Sierra, V. De Romeri, L. J. Flores, D.K. Papoulias | Axionlike particles searches in reactor experiments | 40 pages, 13 figures, 4 tables. SN1987A and Globular Cluster stars
limits updated, references added | null | null | null | hep-ph hep-ex nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Reactor neutrino experiments provide a rich environment for the study of
axionlike particles (ALPs). Using the intense photon flux produced in the
nuclear reactor core, these experiments have the potential to probe ALPs with
masses below 10 MeV. We explore the feasibility of these searches by
considering ALPs produced through Primakoff and Compton-like processes as well
as nuclear transitions. These particles can subsequently interact with the
material of a nearby detector via inverse Primakoff and inverse Compton-like
scatterings, via axio-electric absorption, or they can decay into photon or
electron-positron pairs. We demonstrate that reactor-based neutrino experiments
have a high potential to test ALP-photon couplings and masses, currently probed
only by cosmological and astrophysical observations, thus providing
complementary laboratory-based searches. We furthermore show how reactor
facilities will be able to test previously unexplored regions in the $\sim$MeV
ALP mass range and ALP-electron couplings of the order of $g_{aee} \sim
10^{-8}$ as well as ALP-nucleon couplings of the order of $g_{ann}^{(1)} \sim
10^{-9}$, testing regions beyond TEXONO and Borexino limits.
| [
{
"created": "Thu, 29 Oct 2020 15:54:04 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Nov 2020 02:00:29 GMT",
"version": "v2"
}
] | 2020-11-05 | [
[
"Sierra",
"D. Aristizabal",
""
],
[
"De Romeri",
"V.",
""
],
[
"Flores",
"L. J.",
""
],
[
"Papoulias",
"D. K.",
""
]
] | Reactor neutrino experiments provide a rich environment for the study of axionlike particles (ALPs). Using the intense photon flux produced in the nuclear reactor core, these experiments have the potential to probe ALPs with masses below 10 MeV. We explore the feasibility of these searches by considering ALPs produced through Primakoff and Compton-like processes as well as nuclear transitions. These particles can subsequently interact with the material of a nearby detector via inverse Primakoff and inverse Compton-like scatterings, via axio-electric absorption, or they can decay into photon or electron-positron pairs. We demonstrate that reactor-based neutrino experiments have a high potential to test ALP-photon couplings and masses, currently probed only by cosmological and astrophysical observations, thus providing complementary laboratory-based searches. We furthermore show how reactor facilities will be able to test previously unexplored regions in the $\sim$MeV ALP mass range and ALP-electron couplings of the order of $g_{aee} \sim 10^{-8}$ as well as ALP-nucleon couplings of the order of $g_{ann}^{(1)} \sim 10^{-9}$, testing regions beyond TEXONO and Borexino limits. |
hep-ph/9611285 | Kiwoon Choi | Kiwoon Choi, Eung Jin Chun and Jae Sik Lee | Proton Decay with a Light Gravitino or Axino | 8 pages, RevTex | Phys.Rev.D55:3924-3926,1997 | 10.1103/PhysRevD.55.3924 | KAIST-TH 19/96, CBNU-TH 961108 | hep-ph | null | We consider the proton decay in supersymmetric models with a gravitino or
axino lighter than the proton. This consideration leads to a stringent limit on
the R parity and B violating Yukawa coupling of the superpotential operator
U^c_i D^c_j D^c_k as $\lambda"_{112} < 10^{-15} (m_{3/2}/eV)$ for a light
gravitino, and $\lambda"_{112} < 10^{-15} (F_a/ 10^{10} GeV)$ for a light DFSZ
axino. For hadronic axino, the constraint is weakened by the factor of 10^{3}.
| [
{
"created": "Sat, 9 Nov 1996 04:50:41 GMT",
"version": "v1"
}
] | 2009-12-30 | [
[
"Choi",
"Kiwoon",
""
],
[
"Chun",
"Eung Jin",
""
],
[
"Lee",
"Jae Sik",
""
]
] | We consider the proton decay in supersymmetric models with a gravitino or axino lighter than the proton. This consideration leads to a stringent limit on the R parity and B violating Yukawa coupling of the superpotential operator U^c_i D^c_j D^c_k as $\lambda"_{112} < 10^{-15} (m_{3/2}/eV)$ for a light gravitino, and $\lambda"_{112} < 10^{-15} (F_a/ 10^{10} GeV)$ for a light DFSZ axino. For hadronic axino, the constraint is weakened by the factor of 10^{3}. |
1512.05782 | David Curtin | Zackaria Chacko, David Curtin, Christopher B. Verhaaren | A Quirky Probe of Neutral Naturalness | 6 pages, 2 figures. v2 contains various clarifications compared to
v1, no change in results | Phys. Rev. D 94, 011504 (2016) | 10.1103/PhysRevD.94.011504 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the signals arising from top partner pair production at the LHC
as a probe of theories of Neutral Naturalness. We focus on scenarios in which
top partners carry electroweak charges, such as Folded SUSY or the Quirky
Little Higgs. In this class of theories the top partners are pair produced as
quirky bound states, since they are charged under a mirror color group whose
lightest states are hidden glueballs. The quirks promptly de-excite and
annihilate into glueballs, which decay back to SM fermions via Higgs mixing.
This can give rise to spectacular signatures at the LHC, such displaced decays,
or high-multiplicity prompt production of many hard $\bar b b$ or $\tau^+
\tau^-$ pairs. We show that signals arising from top partner pair production
constitute the primary discovery channel for this class of theories in most
regions of parameter space, and might provide the only experimental probe of
scenarios with sub-cm glueball decay lengths. The measurement of top partner
masses and couplings, which could be used to test the neutral naturalness
mechanism directly, is also a tantalizing possibility.
| [
{
"created": "Thu, 17 Dec 2015 21:00:02 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Nov 2017 22:06:13 GMT",
"version": "v2"
}
] | 2017-12-04 | [
[
"Chacko",
"Zackaria",
""
],
[
"Curtin",
"David",
""
],
[
"Verhaaren",
"Christopher B.",
""
]
] | We consider the signals arising from top partner pair production at the LHC as a probe of theories of Neutral Naturalness. We focus on scenarios in which top partners carry electroweak charges, such as Folded SUSY or the Quirky Little Higgs. In this class of theories the top partners are pair produced as quirky bound states, since they are charged under a mirror color group whose lightest states are hidden glueballs. The quirks promptly de-excite and annihilate into glueballs, which decay back to SM fermions via Higgs mixing. This can give rise to spectacular signatures at the LHC, such displaced decays, or high-multiplicity prompt production of many hard $\bar b b$ or $\tau^+ \tau^-$ pairs. We show that signals arising from top partner pair production constitute the primary discovery channel for this class of theories in most regions of parameter space, and might provide the only experimental probe of scenarios with sub-cm glueball decay lengths. The measurement of top partner masses and couplings, which could be used to test the neutral naturalness mechanism directly, is also a tantalizing possibility. |
hep-ph/0104284 | Frank Krueger | C. Bobeth, T. Ewerth, F. Kr\"uger, J. Urban | Analysis of Neutral Higgs-Boson Contributions to the Decays B_s ->
l^+l^- and B -> K l^+l^- | 29 pages, REVTeX, 8 figures. Minor corrections in Eqs. (5.4), (5.11)
and (6.3) of the published version | Phys.Rev.D64:074014,2001 | 10.1103/PhysRevD.64.074014 | TUM-HEP-411/01 | hep-ph | null | We report on a calculation of Higgs-boson contributions to the decays B_s ->
l^+l^- and B -> K l^+l^- (l=e, mu) which are governed by the effective
Hamiltonian describing b -> s l^+ l^-. Compact formulae for the Wilson
coefficients are provided in the context of the type-II two-Higgs-doublet model
(2HDM) and supersymmetry (SUSY) with minimal flavour violation, focusing on the
case of large tan(beta). We derive, in a model-independent way, constraints on
Higgs-boson-mediated interactions, using present experimental results on rare B
decays including b -> s gamma, B_s -> mu^+ mu^-, and B -> K^(*) mu^+ mu^-. In
particular, we assess the impact of possible scalar and pseudoscalar
interactions transcending the standard model (SM) on the branching ratio of B_s
-> mu^+ mu^- and the forward-backward (FB) asymmetry of mu^- in B -> K mu^+
mu^- decay. We find that the average FB asymmetry, which is unobservably small
within the SM, and therefore a potentially valuable tool to search for new
physics, is predicted to be no greater than 4% for a nominal branching ratio of
about 6x10^{-7}. Moreover, striking effects on the decay spectrum of B -> K
mu^+ mu^- are already ruled out by experimental data on the B_s -> mu^+ mu^-
branching fraction. In addition, we study the constraints on the parameter
space of the 2HDM and SUSY with minimal flavour violation. While the type-II
2HDM does not give any sizable contributions to the above decay modes, we find
that SUSY contributions obeying the constraint on b -> s gamma can affect
significantly the branching ratio of B_s -> mu^+ mu^-. We also comment on
previous calculations contained in the literature.
| [
{
"created": "Thu, 26 Apr 2001 19:15:45 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Apr 2002 20:11:20 GMT",
"version": "v2"
}
] | 2011-03-23 | [
[
"Bobeth",
"C.",
""
],
[
"Ewerth",
"T.",
""
],
[
"Krüger",
"F.",
""
],
[
"Urban",
"J.",
""
]
] | We report on a calculation of Higgs-boson contributions to the decays B_s -> l^+l^- and B -> K l^+l^- (l=e, mu) which are governed by the effective Hamiltonian describing b -> s l^+ l^-. Compact formulae for the Wilson coefficients are provided in the context of the type-II two-Higgs-doublet model (2HDM) and supersymmetry (SUSY) with minimal flavour violation, focusing on the case of large tan(beta). We derive, in a model-independent way, constraints on Higgs-boson-mediated interactions, using present experimental results on rare B decays including b -> s gamma, B_s -> mu^+ mu^-, and B -> K^(*) mu^+ mu^-. In particular, we assess the impact of possible scalar and pseudoscalar interactions transcending the standard model (SM) on the branching ratio of B_s -> mu^+ mu^- and the forward-backward (FB) asymmetry of mu^- in B -> K mu^+ mu^- decay. We find that the average FB asymmetry, which is unobservably small within the SM, and therefore a potentially valuable tool to search for new physics, is predicted to be no greater than 4% for a nominal branching ratio of about 6x10^{-7}. Moreover, striking effects on the decay spectrum of B -> K mu^+ mu^- are already ruled out by experimental data on the B_s -> mu^+ mu^- branching fraction. In addition, we study the constraints on the parameter space of the 2HDM and SUSY with minimal flavour violation. While the type-II 2HDM does not give any sizable contributions to the above decay modes, we find that SUSY contributions obeying the constraint on b -> s gamma can affect significantly the branching ratio of B_s -> mu^+ mu^-. We also comment on previous calculations contained in the literature. |
hep-ph/0209247 | Sachiko Takeuchi | Sachiko Takeuchi and Kiyotaka Shimizu | Pauli-blocking Effect in a Quark Model | 14 pages, 12 figures | Nucl.Phys. A723 (2003) 408-426 | 10.1016/S0375-9474(03)01434-9 | null | hep-ph | null | Pauli-Blocking effect on the kinetic term is investigated by employing the
quark cluster model. The effect can be understood by the change of the degrees
of the mixing between the incoming wave and the 0$\ell$ state of the
inter-cluster wave function, which can be expressed by a potential which is
highly nonlocal. We look into the properties of this effect by comparing
equivalent local potentials. In the channel where the Pauli-blocking effect is
small, the on-shell equivalent local potential simulates the nonlocal potential
well even for the off-shell behavior. On the other hand, the off-shell behavior
is very different from the original one where the effect is large. This
off-shell behavior, however, can well be simulated by considering the nonlocal
matrix elements only between the $0s$ state and the other states. The energy
dependent potentials are also constructed and found to be helpful to understand
the energy dependence of the effect.
| [
{
"created": "Sat, 21 Sep 2002 12:51:44 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Takeuchi",
"Sachiko",
""
],
[
"Shimizu",
"Kiyotaka",
""
]
] | Pauli-Blocking effect on the kinetic term is investigated by employing the quark cluster model. The effect can be understood by the change of the degrees of the mixing between the incoming wave and the 0$\ell$ state of the inter-cluster wave function, which can be expressed by a potential which is highly nonlocal. We look into the properties of this effect by comparing equivalent local potentials. In the channel where the Pauli-blocking effect is small, the on-shell equivalent local potential simulates the nonlocal potential well even for the off-shell behavior. On the other hand, the off-shell behavior is very different from the original one where the effect is large. This off-shell behavior, however, can well be simulated by considering the nonlocal matrix elements only between the $0s$ state and the other states. The energy dependent potentials are also constructed and found to be helpful to understand the energy dependence of the effect. |
1812.00694 | Ulrich Haisch | Ulrich Haisch and Giacomo Polesello | Searching for production of dark matter in association with top quarks
at the LHC | 20 pages, 8 figures, 1 table; v2: version accepted by JHEP | null | 10.1007/JHEP02(2019)029 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the framework of spin-0 $s$-channel dark matter (DM) simplified models, we
reassess the sensitivity of future LHC runs to the production of DM in
association with top quarks. We consider two different missing transverse
energy ($E_T^{\mathrm{miss}}$) signatures, namely production of DM in
association with either a $t \bar t$ pair or a top quark and a $W$ boson, where
the latter channel has not been the focus of a dedicated analysis prior to this
work. Final states with two leptons are studied and a realistic analysis
strategy is developed that simultaneously takes into account both channels.
Compared to other existing search strategies the proposed combination of $t
\bar t + E_T^{\mathrm{miss}}$ and $t W + E_T^{\mathrm{miss}}$ production
provides a significantly improved coverage of the parameter space of spin-0
$s$-channel DM simplified models.
| [
{
"created": "Mon, 3 Dec 2018 12:08:57 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Feb 2019 18:31:37 GMT",
"version": "v2"
}
] | 2019-02-20 | [
[
"Haisch",
"Ulrich",
""
],
[
"Polesello",
"Giacomo",
""
]
] | In the framework of spin-0 $s$-channel dark matter (DM) simplified models, we reassess the sensitivity of future LHC runs to the production of DM in association with top quarks. We consider two different missing transverse energy ($E_T^{\mathrm{miss}}$) signatures, namely production of DM in association with either a $t \bar t$ pair or a top quark and a $W$ boson, where the latter channel has not been the focus of a dedicated analysis prior to this work. Final states with two leptons are studied and a realistic analysis strategy is developed that simultaneously takes into account both channels. Compared to other existing search strategies the proposed combination of $t \bar t + E_T^{\mathrm{miss}}$ and $t W + E_T^{\mathrm{miss}}$ production provides a significantly improved coverage of the parameter space of spin-0 $s$-channel DM simplified models. |
hep-ph/0311209 | Alexander Lanyov | A.A. Belkov, G.Bohm, A.V. Lanyov | What we have learned from direct CP violation studies in kaon decays | Reference added | Czech.J.Phys. 55 (2004) B193-B206 | null | null | hep-ph | null | A self-consistent analysis of K --> 2pi and K --> 3pi decays within a unique
framework of chiral dynamics applied to the QCD-corrected weak nonleptonic
quark lagrangian has been performed. The results on K --> 2pi amplitudes at
O(p^6), including the value for epsilon'/epsilon, are compared with experiment
to fix phenomenological B-factors for mesonic matrix elements of nonpenguin and
penguin four-quark operators. The dependence of these B-factors on different
theoretical uncertainties and experimental errors of various input parameters
is investigated. Finally, we present our estimates at O(p^6) for the CP
asymmetry of linear slope parameters in the K+- --> 3pi Dalitz plot.
| [
{
"created": "Mon, 17 Nov 2003 12:55:37 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Dec 2003 13:38:40 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Belkov",
"A. A.",
""
],
[
"Bohm",
"G.",
""
],
[
"Lanyov",
"A. V.",
""
]
] | A self-consistent analysis of K --> 2pi and K --> 3pi decays within a unique framework of chiral dynamics applied to the QCD-corrected weak nonleptonic quark lagrangian has been performed. The results on K --> 2pi amplitudes at O(p^6), including the value for epsilon'/epsilon, are compared with experiment to fix phenomenological B-factors for mesonic matrix elements of nonpenguin and penguin four-quark operators. The dependence of these B-factors on different theoretical uncertainties and experimental errors of various input parameters is investigated. Finally, we present our estimates at O(p^6) for the CP asymmetry of linear slope parameters in the K+- --> 3pi Dalitz plot. |
1209.3246 | Feng Yuan | Xiangdong Ji, Xiaonu Xiong, Feng Yuan | Transverse Polarization of the Nucleon in Parton Picture | 10 pages | null | 10.1016/j.physletb.2012.09.027 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The proton's transverse polarization structure is examined in terms of the
Lorentz-covariant Pauli-Lubanski vector in QCD. We find that there are
contributions from leading, subleading, and next-to-subleading partonic
contributions in the light-front system of coordinates. The subleading and
next-to-subleading contributions are related to the leading one through Lorentz
symmetry. And the leading contribution obeys a simple partonic angular momentum
sum rule that gives a clear physical interpretation to a relation known
previously.
| [
{
"created": "Fri, 14 Sep 2012 16:13:45 GMT",
"version": "v1"
}
] | 2015-06-11 | [
[
"Ji",
"Xiangdong",
""
],
[
"Xiong",
"Xiaonu",
""
],
[
"Yuan",
"Feng",
""
]
] | The proton's transverse polarization structure is examined in terms of the Lorentz-covariant Pauli-Lubanski vector in QCD. We find that there are contributions from leading, subleading, and next-to-subleading partonic contributions in the light-front system of coordinates. The subleading and next-to-subleading contributions are related to the leading one through Lorentz symmetry. And the leading contribution obeys a simple partonic angular momentum sum rule that gives a clear physical interpretation to a relation known previously. |
1303.0668 | Minoru Nagai | Takeo Moroi and Minoru Nagai | Probing Supersymmetric Model with Heavy Sfermions Using Leptonic Flavor
and CP Violations | 13 pages, 4 figures, published version | Phys.Lett.B723 (2013), 107-112 | 10.1016/j.physletb.2013.04.049 | UT-13-08 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study leptonic flavor and CP violating observables in supersymmetric
(SUSY) models with heavy sfermions, which is motivated by the recent results of
the LHC experiments (i.e., the discovery of the Higgs-like boson with the mass
of about 126 GeV and the negative searches for the superparticles). Even if the
sfermion masses are of O(10-100 TeV), signals may be within the reach of future
leptonic flavor- and CP-violation experiments assuming that the off-diagonal
elements of the sfermion mass matrices are unsuppressed compared to the
diagonal ones. We also consider the SUSY contribution to the K0-K0bar mixing
paraemters; we show that the leptonic observables can become as powerful as
those in K0-K0bar mixing to constrain SUSY models.
| [
{
"created": "Mon, 4 Mar 2013 10:39:02 GMT",
"version": "v1"
},
{
"created": "Thu, 30 May 2013 08:32:14 GMT",
"version": "v2"
}
] | 2015-06-15 | [
[
"Moroi",
"Takeo",
""
],
[
"Nagai",
"Minoru",
""
]
] | We study leptonic flavor and CP violating observables in supersymmetric (SUSY) models with heavy sfermions, which is motivated by the recent results of the LHC experiments (i.e., the discovery of the Higgs-like boson with the mass of about 126 GeV and the negative searches for the superparticles). Even if the sfermion masses are of O(10-100 TeV), signals may be within the reach of future leptonic flavor- and CP-violation experiments assuming that the off-diagonal elements of the sfermion mass matrices are unsuppressed compared to the diagonal ones. We also consider the SUSY contribution to the K0-K0bar mixing paraemters; we show that the leptonic observables can become as powerful as those in K0-K0bar mixing to constrain SUSY models. |
0910.2810 | Luca Merlo | Luca Merlo | Weak complementarity from discrete symmetries | 5 pages, 1 figure; Proceeding for the XXXIII International Conference
of Theoretical Physics: ``USTRON09 -- Matter to the Deepest: Recent
Developments in Physics of Fundamental Interactions'' | Acta Phys.Polon.B40:3179-3184,2009 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The neutrino oscillation data find a good approximation in the so-called
tri-bimaximal pattern. Recently a paper appeared showing that also the
bimaximal pattern, which is already ruled out by the measurements, could be a
very good starting point in order to describe the lepton mixing. In this paper
I review both the flavour structures and then I present an explicit flavour
model based on the discrete group S4, in which the PMNS mixing matrix is of the
bimaximal form in first approximation and after it receives corrections which
bring it in agreement with the data. The resulting spectrum of light neutrinos
shows a moderate normal hierarchy and is compatible, within large ambiguities,
with the constraints from leptogenesis as an explanation of the baryon
asymmetry in the Universe.
| [
{
"created": "Thu, 15 Oct 2009 08:51:19 GMT",
"version": "v1"
}
] | 2010-02-11 | [
[
"Merlo",
"Luca",
""
]
] | The neutrino oscillation data find a good approximation in the so-called tri-bimaximal pattern. Recently a paper appeared showing that also the bimaximal pattern, which is already ruled out by the measurements, could be a very good starting point in order to describe the lepton mixing. In this paper I review both the flavour structures and then I present an explicit flavour model based on the discrete group S4, in which the PMNS mixing matrix is of the bimaximal form in first approximation and after it receives corrections which bring it in agreement with the data. The resulting spectrum of light neutrinos shows a moderate normal hierarchy and is compatible, within large ambiguities, with the constraints from leptogenesis as an explanation of the baryon asymmetry in the Universe. |
1509.00736 | Dian-Yong Chen | Dian-Yong Chen, Xiang Liu, Takayuki Matsuki | Search for missing $\psi(4S)$ in the $e^+e^-\to \pi^+\pi^-\psi(2S)$
process | 9 pages, 10 figures | Phys. Rev. D 93, 034028 (2016) | 10.1103/PhysRevD.93.034028 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A detailed analysis to find a missing $\psi(4S)$ is made by utilizing the
recent precise mesurements of the cross section for the process $e^+e^-\to
\psi(2S)\pi^+\pi^-$ by Belle. Assuming three resonances $Y(4360)$, $Y(4660)$,
and $\psi(4S)$ to fit the data, we obtain the resonance parameters for
$\psi(4S)$ as $m=4243$ MeV and $\Gamma=16 \pm 31$ MeV showing a narrow state as
predicted before. A combined fit to the data $e^+ e^- \to \psi(2S) \pi^+ \pi^-,
\ h_c \pi^+ \pi^-$, and $\chi_{c0} \omega$ is also performed to obtain the
similar resonance parameters of $\psi(4S)$. The upper limit of the branching
ratio is fitted to be $\mathcal{B}(\psi(4S)\to\psi(2S)\pi^+\pi^-) < 3\times
10^{-3}$, which can be understood by hadronic loop contributions in reasonable
parameters range. In addition, the ratios of the branching ratios of the
$\psi(4S)$ dipion transition to the one of $\psi(4S)\to\chi_{c0}\omega$ are
fitted, which can be further measured by BESIII and forthcoming BelleII to
confirm the existence of $\psi(4S)$.
| [
{
"created": "Wed, 2 Sep 2015 15:16:33 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Feb 2016 16:54:20 GMT",
"version": "v2"
},
{
"created": "Thu, 18 Feb 2016 02:22:11 GMT",
"version": "v3"
}
] | 2016-02-24 | [
[
"Chen",
"Dian-Yong",
""
],
[
"Liu",
"Xiang",
""
],
[
"Matsuki",
"Takayuki",
""
]
] | A detailed analysis to find a missing $\psi(4S)$ is made by utilizing the recent precise mesurements of the cross section for the process $e^+e^-\to \psi(2S)\pi^+\pi^-$ by Belle. Assuming three resonances $Y(4360)$, $Y(4660)$, and $\psi(4S)$ to fit the data, we obtain the resonance parameters for $\psi(4S)$ as $m=4243$ MeV and $\Gamma=16 \pm 31$ MeV showing a narrow state as predicted before. A combined fit to the data $e^+ e^- \to \psi(2S) \pi^+ \pi^-, \ h_c \pi^+ \pi^-$, and $\chi_{c0} \omega$ is also performed to obtain the similar resonance parameters of $\psi(4S)$. The upper limit of the branching ratio is fitted to be $\mathcal{B}(\psi(4S)\to\psi(2S)\pi^+\pi^-) < 3\times 10^{-3}$, which can be understood by hadronic loop contributions in reasonable parameters range. In addition, the ratios of the branching ratios of the $\psi(4S)$ dipion transition to the one of $\psi(4S)\to\chi_{c0}\omega$ are fitted, which can be further measured by BESIII and forthcoming BelleII to confirm the existence of $\psi(4S)$. |
1412.5794 | Nodoka Yamanaka | Nodoka Yamanaka | Quark scalar, axial and tensor charges in the Schwinger-Dyson formalism | 6 pages, 5 figures. Proceedings of the XI th International Conference
on Quark Confinement and the Hadron Spectrum (Confinement XI) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The quark scalar, axial and tensor charges of nucleon are calculated in the
Schwinger-Dyson formalism. We first calculate these charges in the
rainbow-ladder truncation using the IR cut quark-gluon vertex, and show that
the result is in agreement with the known data. We then perform the same
calculation with the phenomenological IR singular quark-gluon vertex. In this
case, the Schwinger-Dyson equation does not converge. We show that this result
suggests the requirement of additional corrections to the rainbow-ladder
truncation, due to the interaction between quark and gluons in the deep IR
region.
| [
{
"created": "Thu, 18 Dec 2014 10:31:01 GMT",
"version": "v1"
}
] | 2014-12-19 | [
[
"Yamanaka",
"Nodoka",
""
]
] | The quark scalar, axial and tensor charges of nucleon are calculated in the Schwinger-Dyson formalism. We first calculate these charges in the rainbow-ladder truncation using the IR cut quark-gluon vertex, and show that the result is in agreement with the known data. We then perform the same calculation with the phenomenological IR singular quark-gluon vertex. In this case, the Schwinger-Dyson equation does not converge. We show that this result suggests the requirement of additional corrections to the rainbow-ladder truncation, due to the interaction between quark and gluons in the deep IR region. |
hep-ph/9909336 | David Broadhurst | D. J. Broadhurst | Four-loop Dyson-Schwinger-Johnson anatomy | 11 pages, LaTeX | Phys.Lett. B466 (1999) 319-325 | 10.1016/S0370-2693(99)01083-7 | OUT--4102--81 | hep-ph hep-th | null | Dyson-Schwinger equations are used to evaluate the 4-loop anomalous
dimensions of quenched QED in terms of finite, scheme-independent, 3-loop
integrals. Three of the results serve as strong checks of terms from
scheme-dependent 4-loop QCD calculations. The fourth, for the anomalous
dimension of $\bar\psi\sigma_{\mu\nu}\psi$, was previously known only to 2-loop
order. The 4-loop beta function has 24 unambiguous terms. Two of the simplest
give $\beta_4=\frac13(22-160)=-46$. The rational, $\zeta_3$ and $\zeta_5$ parts
of the other 22 miraculously sum to zero. Vertex anomalous dimensions have 40
terms, with no dramatic cancellations. Our methods come from work by the late
Kenneth Johnson, done more than 30 years ago. They are entirely free of the
subtractions and infrared rearrangements of later methods.
| [
{
"created": "Mon, 13 Sep 1999 22:15:49 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Broadhurst",
"D. J.",
""
]
] | Dyson-Schwinger equations are used to evaluate the 4-loop anomalous dimensions of quenched QED in terms of finite, scheme-independent, 3-loop integrals. Three of the results serve as strong checks of terms from scheme-dependent 4-loop QCD calculations. The fourth, for the anomalous dimension of $\bar\psi\sigma_{\mu\nu}\psi$, was previously known only to 2-loop order. The 4-loop beta function has 24 unambiguous terms. Two of the simplest give $\beta_4=\frac13(22-160)=-46$. The rational, $\zeta_3$ and $\zeta_5$ parts of the other 22 miraculously sum to zero. Vertex anomalous dimensions have 40 terms, with no dramatic cancellations. Our methods come from work by the late Kenneth Johnson, done more than 30 years ago. They are entirely free of the subtractions and infrared rearrangements of later methods. |
hep-ph/0105084 | Kaustubh Agashe | K. Agashe, N.G. Deshpande, G.-H. Wu (ITS, University of Oregon) | Universal Extra Dimensions and b -> s gamma | Latex, 8 pages, 2 eps figs. included. Revised version (to be
published in Phys. Lett. B): a reference has been added | Phys.Lett. B514 (2001) 309-314 | 10.1016/S0370-2693(01)00791-2 | OITS-704 | hep-ph | null | We analyze the effect of flat universal extra dimensions (i.e., extra
dimensions accessible to all SM fields) on the process b -> s gamma. With one
Higgs doublet, the dominant contribution at one-loop is from Kaluza-Klein (KK)
states of the charged would-be-Goldstone boson (WGB) and of the top quark. The
resulting constraint on the size of the extra dimension is comparable to the
constraint from T parameter. In two-Higgs doublet model II, the contribution of
zero-mode and KK states of physical charged Higgs can cancel the contribution
from WGB KK states. Therefore, in this model, there is no constraint on the
size of the extra dimensions from the process b -> s gamma and also the
constraint on the mass of the charged Higgs from this process is weakened
compared to 4D. In two Higgs doublet model I, the contribution of the zero-mode
and KK states of physical charged Higgs and that of the KK states of WGB are of
the same sign. Thus, in this model and for small tan beta, the constraint on
the size of the extra dimensions is stronger than in one Higgs doublet model
and also the constraint on the mass of the charged Higgs is stronger than in
4D.
| [
{
"created": "Wed, 9 May 2001 23:40:49 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Jun 2001 07:14:08 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Agashe",
"K.",
"",
"ITS, University of Oregon"
],
[
"Deshpande",
"N. G.",
"",
"ITS, University of Oregon"
],
[
"Wu",
"G. -H.",
"",
"ITS, University of Oregon"
]
] | We analyze the effect of flat universal extra dimensions (i.e., extra dimensions accessible to all SM fields) on the process b -> s gamma. With one Higgs doublet, the dominant contribution at one-loop is from Kaluza-Klein (KK) states of the charged would-be-Goldstone boson (WGB) and of the top quark. The resulting constraint on the size of the extra dimension is comparable to the constraint from T parameter. In two-Higgs doublet model II, the contribution of zero-mode and KK states of physical charged Higgs can cancel the contribution from WGB KK states. Therefore, in this model, there is no constraint on the size of the extra dimensions from the process b -> s gamma and also the constraint on the mass of the charged Higgs from this process is weakened compared to 4D. In two Higgs doublet model I, the contribution of the zero-mode and KK states of physical charged Higgs and that of the KK states of WGB are of the same sign. Thus, in this model and for small tan beta, the constraint on the size of the extra dimensions is stronger than in one Higgs doublet model and also the constraint on the mass of the charged Higgs is stronger than in 4D. |
1306.3155 | Stanislaus Janowski | Stanislaus Janowski | Quarkonium and glueball admixtures of the scalar-isoscalar resonances
f0(1370), f0(1500) and f0(1710) | Prepared for the proceedings of Excited QCD 2013, Sarajevo/Bosnia and
Herzegovina, February 3-9, 2013. 6 pages, 1 table | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the U(3)R x U(3)L extended Linear Sigma Model with the ordinary
(pseudo)scalar and (axial)vector mesons as well as a scalar glueball, we study
the vacuum phenomenology of the scalar-isoscalar resonances f0(1370), f0(1500)
and f0(1710). We present here a solution, based only on the masses and not yet
on decays, in which the resonances f0(1370) and f0(1500) are predominantly
nonstrange and strange qbar-q states respectively, and the resonance f0(1710)
is predominantly a scalar glueball.
| [
{
"created": "Thu, 13 Jun 2013 16:23:27 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Jun 2013 11:09:59 GMT",
"version": "v2"
},
{
"created": "Tue, 3 Dec 2013 16:19:27 GMT",
"version": "v3"
}
] | 2013-12-04 | [
[
"Janowski",
"Stanislaus",
""
]
] | Using the U(3)R x U(3)L extended Linear Sigma Model with the ordinary (pseudo)scalar and (axial)vector mesons as well as a scalar glueball, we study the vacuum phenomenology of the scalar-isoscalar resonances f0(1370), f0(1500) and f0(1710). We present here a solution, based only on the masses and not yet on decays, in which the resonances f0(1370) and f0(1500) are predominantly nonstrange and strange qbar-q states respectively, and the resonance f0(1710) is predominantly a scalar glueball. |
hep-ph/0212253 | Dmitri Kuzmenko | Yu.A. Simonov (ITEP, Moscow) | From 3 nucleons to 3 quarks | 9 pages, invited talk at the miniconference dedicated to the 80-th
year celebration of Professor Karen A.Ter-Martirosyan, 30 September - 1
October, ITEP, Moscow | Phys.Atom.Nucl.66:2033-2037,2003; Yad.Fiz.66:2083-2087,2003 | 10.1134/1.1625745 | null | hep-ph | null | Some short history of few-body methods originated from the famous
Skornyakov-Ter-Martirosyan equation is given, including latest development of
Faddeev formalism and Efimov states. The 3q system is shown to require an
alternative, which is provided by the hyperspherical method (K-harmonics) which
is highly successful for baryons.
| [
{
"created": "Tue, 17 Dec 2002 17:13:13 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Simonov",
"Yu. A.",
"",
"ITEP, Moscow"
]
] | Some short history of few-body methods originated from the famous Skornyakov-Ter-Martirosyan equation is given, including latest development of Faddeev formalism and Efimov states. The 3q system is shown to require an alternative, which is provided by the hyperspherical method (K-harmonics) which is highly successful for baryons. |
1105.2533 | Timothy Burns | T. J. Burns | How the small hyperfine splitting of P-wave mesons evades large loop
corrections | Journal version. Two references and one data set added | Phys.Rev.D84:034021,2011 | 10.1103/PhysRevD.84.034021 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent discoveries of the bottomonia states h_b(1P) and h_b(2P) confirm
the quark model prediction, already verified in the charmonia sector, that the
hyperfine splitting of P-wave mesons is very small. The striking agreement is
somewhat surprising because the non-relativistic result, for which the
splitting is zero, may be modified due to large mass shifts from coupling to
open flavour meson pairs. This paper is based on the observation that in most
models hyperfine splitting remains small despite what are in many cases large
mass shifts. This effect is shown to be a generic feature of models in which
the coupling is driven by the creation of a spin-one pair.
| [
{
"created": "Thu, 12 May 2011 17:16:57 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Aug 2011 15:39:51 GMT",
"version": "v2"
}
] | 2011-09-08 | [
[
"Burns",
"T. J.",
""
]
] | The recent discoveries of the bottomonia states h_b(1P) and h_b(2P) confirm the quark model prediction, already verified in the charmonia sector, that the hyperfine splitting of P-wave mesons is very small. The striking agreement is somewhat surprising because the non-relativistic result, for which the splitting is zero, may be modified due to large mass shifts from coupling to open flavour meson pairs. This paper is based on the observation that in most models hyperfine splitting remains small despite what are in many cases large mass shifts. This effect is shown to be a generic feature of models in which the coupling is driven by the creation of a spin-one pair. |
hep-ph/9802363 | Joan Sola | Joan Sola | t --> W+ b and t --> H+ b at the quantum level in the MSSM | 9 pages, LaTeX, 3 figures included using epsfig. Talk presented at
the International Workshop on Quantum Effects in the MSSM, Barcelona,
September 9-13, 1997. To appear in the Proceedings | null | null | UAB-FT-437 | hep-ph | null | We compare the standard top quark decay and the charged Higgs decay of the
top quark, t --> W+ b and t --> H+ b, at the quantum level in the MSSM. While
the SUSY loop corrections to the standard top quark decay are only of a few
percent, it turns out that t --> H+ b is a most promising candidate for
carrying large quantum SUSY signatures. As a result, the (tan(beta), M_{H+-})
exclusion plots presented by the CDF Collaboration should be thoroughly revised
in the light of the MSSM.
| [
{
"created": "Thu, 19 Feb 1998 16:56:25 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Sola",
"Joan",
""
]
] | We compare the standard top quark decay and the charged Higgs decay of the top quark, t --> W+ b and t --> H+ b, at the quantum level in the MSSM. While the SUSY loop corrections to the standard top quark decay are only of a few percent, it turns out that t --> H+ b is a most promising candidate for carrying large quantum SUSY signatures. As a result, the (tan(beta), M_{H+-}) exclusion plots presented by the CDF Collaboration should be thoroughly revised in the light of the MSSM. |
2406.04900 | Francisco Xavier De Azeredo Azeredo F.X. | Francisco X. Azeredo, Dyana C. Duarte, Ricardo L. S. Farias, Gast\~ao
Krein and Rudnei O. Ramos | Deconfinement and chiral phase transitions in quark matter with chiral
imbalance | 15 pages, 10 figures | null | null | null | hep-ph hep-lat hep-th nucl-th | http://creativecommons.org/licenses/by/4.0/ | We study the thermodynamics of the Polyakov--Nambu--Jona-Lasinio model
considering the effects of an effective chiral chemical potential. We offer a
new parametrization of the Polyakov loop potential depending on temperature and
the chemical potential which, when used together with a proper regularization
scheme of vacuum contributions, predicts results consistent with those from
lattice simulations.
| [
{
"created": "Fri, 7 Jun 2024 12:49:28 GMT",
"version": "v1"
}
] | 2024-06-10 | [
[
"Azeredo",
"Francisco X.",
""
],
[
"Duarte",
"Dyana C.",
""
],
[
"Farias",
"Ricardo L. S.",
""
],
[
"Krein",
"Gastão",
""
],
[
"Ramos",
"Rudnei O.",
""
]
] | We study the thermodynamics of the Polyakov--Nambu--Jona-Lasinio model considering the effects of an effective chiral chemical potential. We offer a new parametrization of the Polyakov loop potential depending on temperature and the chemical potential which, when used together with a proper regularization scheme of vacuum contributions, predicts results consistent with those from lattice simulations. |
1906.01020 | John M. Campbell | John M. Campbell, R. Keith Ellis and Satyajit Seth | H+1 jet production revisited | 19 pages, 8 figures | null | 10.1007/JHEP10(2019)136 | FERMILAB-PUB-19-189-T, IPPP/19/33 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the next-to-next-to-leading order (NNLO) calculation of the Higgs
boson+1~jet production process, calculated in the $m_t \to \infty$ effective
field theory. We perform a detailed comparison of the result calculated using
the jettiness slicing method, with published results obtained using subtraction
methods. The results of the jettiness calculation agree with the two previous
subtraction calculations at benchmark points. The performance of the jettiness
slicing approach is greatly improved by adopting a definition of 1-jettiness
that accounts for the boost of the Born system. Nevertheless, the results
demonstrate that power corrections in the jettiness slicing method remain
significant. At large transverse momentum the effect of power corrections is
much reduced, as expected.
| [
{
"created": "Mon, 3 Jun 2019 18:38:15 GMT",
"version": "v1"
}
] | 2020-01-08 | [
[
"Campbell",
"John M.",
""
],
[
"Ellis",
"R. Keith",
""
],
[
"Seth",
"Satyajit",
""
]
] | We revisit the next-to-next-to-leading order (NNLO) calculation of the Higgs boson+1~jet production process, calculated in the $m_t \to \infty$ effective field theory. We perform a detailed comparison of the result calculated using the jettiness slicing method, with published results obtained using subtraction methods. The results of the jettiness calculation agree with the two previous subtraction calculations at benchmark points. The performance of the jettiness slicing approach is greatly improved by adopting a definition of 1-jettiness that accounts for the boost of the Born system. Nevertheless, the results demonstrate that power corrections in the jettiness slicing method remain significant. At large transverse momentum the effect of power corrections is much reduced, as expected. |
1512.06028 | Takaaki Nomura | R. Benbrik, Chuan-Hung Chen, Takaaki Nomura | Higgs singlet boson as a diphoton resonance in a vector-like quark model | 18 pages, 4 figures, title is slightly changed,To be published in
Phys. Rev. D | Phys. Rev. D 93, 055034 (2016) | 10.1103/PhysRevD.93.055034 | KIAS-P15066 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | ATLAS and CMS recently show the first results from run 2 of the Large Hadron
Collider (LHC) at $\sqrt{s}=13$ TeV. A resonant bump at a mass of around 750
GeV in the diphoton invariant mass spectrum is indicated and the corresponding
diphoton production cross section is around 3-10 fb. Motivated by the LHC
diphoton excess, we propose that the possible resonance candidate is a Higgs
singlet. To produce the Higgs singlet via gluon-gluon fusion process, we embed
the Higgs singlet in the framework of vector-like triplet quark (VLTQ) model.
As a result, the Higgs singlet decaying to diphoton final state is via VLTQ
loops. Using the enhanced number of new quarks and new Yukawa couplings of the
VLTQs and Higgs singlet, we successfully explain the diphoton production cross
section. We find that the width of the Higgs singlet is below 1 GeV, its
production cross section can be of order of 1 pb at $\sqrt{s}=13$ TeV, and the
branching ratio for it decaying to diphoton is around $0.017$ and is
insensitive to the masses of VLTQs and new Yukawa couplings. We find a strong
correlation between the Higgs Yukawa couplings to $s$-$b$ and $c$-$t$; the
resulted branching ratio for $t \to c h$ can be $1.1\times 10^{-4}$ when the
constraint from $B_s$ oscillation is applied. With the constrained parameter
values, the signal strength for the SM Higgs decaying to diphoton is
$\mu_{\gamma\gamma}< 1.18$, which is consistent with the current measurements
at ATLAS and CMS.
| [
{
"created": "Fri, 18 Dec 2015 16:42:13 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Dec 2015 13:31:08 GMT",
"version": "v2"
},
{
"created": "Wed, 23 Mar 2016 14:51:39 GMT",
"version": "v3"
}
] | 2016-03-30 | [
[
"Benbrik",
"R.",
""
],
[
"Chen",
"Chuan-Hung",
""
],
[
"Nomura",
"Takaaki",
""
]
] | ATLAS and CMS recently show the first results from run 2 of the Large Hadron Collider (LHC) at $\sqrt{s}=13$ TeV. A resonant bump at a mass of around 750 GeV in the diphoton invariant mass spectrum is indicated and the corresponding diphoton production cross section is around 3-10 fb. Motivated by the LHC diphoton excess, we propose that the possible resonance candidate is a Higgs singlet. To produce the Higgs singlet via gluon-gluon fusion process, we embed the Higgs singlet in the framework of vector-like triplet quark (VLTQ) model. As a result, the Higgs singlet decaying to diphoton final state is via VLTQ loops. Using the enhanced number of new quarks and new Yukawa couplings of the VLTQs and Higgs singlet, we successfully explain the diphoton production cross section. We find that the width of the Higgs singlet is below 1 GeV, its production cross section can be of order of 1 pb at $\sqrt{s}=13$ TeV, and the branching ratio for it decaying to diphoton is around $0.017$ and is insensitive to the masses of VLTQs and new Yukawa couplings. We find a strong correlation between the Higgs Yukawa couplings to $s$-$b$ and $c$-$t$; the resulted branching ratio for $t \to c h$ can be $1.1\times 10^{-4}$ when the constraint from $B_s$ oscillation is applied. With the constrained parameter values, the signal strength for the SM Higgs decaying to diphoton is $\mu_{\gamma\gamma}< 1.18$, which is consistent with the current measurements at ATLAS and CMS. |
hep-ph/0112018 | Belli Pierluigi | P. Belli, R. Bernabei, M. Amato, F. Cappella, R. Cerulli, C.J. Dai,
H.L. He, G. Ignesti, A. Incicchitti, H.H. Kuang, J.M. Ma, F. Montecchia, F.
Nozzoli, D. Prosperi | WIMP search by the DAMA experiment at Gran Sasso | Talk at COSMO-01 Workshop, Rovaniemi, Finland, August 30 - September
4, 2001 | null | null | null | hep-ph astro-ph hep-ex | null | DAMA is searching for rare processes by developing and using several kinds of
radiopure scintillators: in particular, NaI(Tl), liquid Xenon and CaF$_2$(Eu).
The main results are here summarized with particular attention to the
investigation of the WIMP annual modulation signature.
| [
{
"created": "Mon, 3 Dec 2001 10:47:54 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Belli",
"P.",
""
],
[
"Bernabei",
"R.",
""
],
[
"Amato",
"M.",
""
],
[
"Cappella",
"F.",
""
],
[
"Cerulli",
"R.",
""
],
[
"Dai",
"C. J.",
""
],
[
"He",
"H. L.",
""
],
[
"Ignesti",
"G.",
""
... | DAMA is searching for rare processes by developing and using several kinds of radiopure scintillators: in particular, NaI(Tl), liquid Xenon and CaF$_2$(Eu). The main results are here summarized with particular attention to the investigation of the WIMP annual modulation signature. |
1405.4670 | Kazunori Nakayama | Kazunori Nakayama, Fuminobu Takahashi, Tsutomu T. Yanagida | Extra light fermions in $E_6$-inspired models and the 3.5 keV X-ray line
signal | 7 pages | null | 10.1016/j.physletb.2014.08.061 | UT-14-25, TU-971, IPMU14-0122 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a scenario in which extra light fermions in an $E_6$-inspired U(1)
extension of the standard model constitute the dark matter, as a simple
variation of our model for dark radiation presented in 2010. Interestingly, for
the light fermions of mass about 7 keV, they radiatively decay into active
neutrinos and photons with a lifetime in the range of $10^{27}-10^{28}$
seconds, which naturally explains the recently discovered 3.5 keV X-ray line
signal.
| [
{
"created": "Mon, 19 May 2014 10:48:19 GMT",
"version": "v1"
}
] | 2015-06-19 | [
[
"Nakayama",
"Kazunori",
""
],
[
"Takahashi",
"Fuminobu",
""
],
[
"Yanagida",
"Tsutomu T.",
""
]
] | We propose a scenario in which extra light fermions in an $E_6$-inspired U(1) extension of the standard model constitute the dark matter, as a simple variation of our model for dark radiation presented in 2010. Interestingly, for the light fermions of mass about 7 keV, they radiatively decay into active neutrinos and photons with a lifetime in the range of $10^{27}-10^{28}$ seconds, which naturally explains the recently discovered 3.5 keV X-ray line signal. |
hep-ph/0309319 | Javier Vijande ASenjo | J. Vijande, F. Fernandez and A. Valcarce | The ${q}\bar{q}$ spectra and the structure of the scalar mesons | 5 pages, to be published in the Proceedings of the "10th
International Conference on Hadron Spectroscopy", Aschaffenburg, Germany,
Aug. 31 - Sep. 6, 2003 | AIP Conf. Proc. 717, 352-356, (2004) | 10.1063/1.1799731 | null | hep-ph | null | The ${q}\bar{q}$ spectrum is studied within a chiral constituent quark model.
It provides with a good fit of the available experimental data from light
(vector and pseudoscalar) to heavy mesons including some recent results on
charmonium. The $0^{++}$ light mesons and the new $D$ states measured at
different factories cannot be described as $q\bar q$ pairs and a tetraquark
structure is suggested.
| [
{
"created": "Mon, 29 Sep 2003 10:00:26 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Oct 2003 07:30:32 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Vijande",
"J.",
""
],
[
"Fernandez",
"F.",
""
],
[
"Valcarce",
"A.",
""
]
] | The ${q}\bar{q}$ spectrum is studied within a chiral constituent quark model. It provides with a good fit of the available experimental data from light (vector and pseudoscalar) to heavy mesons including some recent results on charmonium. The $0^{++}$ light mesons and the new $D$ states measured at different factories cannot be described as $q\bar q$ pairs and a tetraquark structure is suggested. |
hep-ph/0601131 | Magno Machado | V.P. Goncalves, M.V.T. Machado | Heavy Quarks and Meson Production in Ultraperipheral Heavy Ion
Collisions | 6 pages, 1 figure. To appear in the proceedings of International
Workshop on Astronomy and Relativistic Astrophysics (IWARA2005), 2-5 Oct.
2005, Natal, Brazil | Int.J.Mod.Phys.D16:533-539,2007 | 10.1142/S0218271807010365 | null | hep-ph nucl-ex nucl-th | null | We report on our recent investigations in photonuclear production of heavy
quarks and vector meson in ultraperipheral heavy ion collisions. In particular,
our theoretical predictions are compared with the recent experimental
measurements on coherent rho (STAR) and J/Psi (PHENIX) photoproduction at RHIC
and estimates for LHC are given.
| [
{
"created": "Tue, 17 Jan 2006 15:31:10 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Goncalves",
"V. P.",
""
],
[
"Machado",
"M. V. T.",
""
]
] | We report on our recent investigations in photonuclear production of heavy quarks and vector meson in ultraperipheral heavy ion collisions. In particular, our theoretical predictions are compared with the recent experimental measurements on coherent rho (STAR) and J/Psi (PHENIX) photoproduction at RHIC and estimates for LHC are given. |
2311.05125 | Arunansu Sil | Soumen Kumar Manna and Arunansu Sil | Effects of Electroweak Symmetry Breaking on Axion Like Particles as Dark
Matter | 13 pages, 10 figures, version to appear in PRD | null | null | null | hep-ph hep-th | http://creativecommons.org/licenses/by/4.0/ | Axion like particles (ALPs), the pseudo Nambu-Goldstone bosons associated to
the spontaneous breaking of global symmetry, have emerged as promising dark
matter candidates. Conventionally, in the context of misalignment mechanism,
the non-thermally produced ALPs happen to stay frozen due to Hubble friction
initially and at a later stage, they begin to oscillate (before
matter-radiation equality) at characteristic frequencies defined by their
masses and behaving like cold dark matter. In this work, we study the influence
of electroweak symmetry breaking (EWSB), through a higher order Higgs portal
interaction, on the evolution of ALPs. Such an interaction is found to
contribute partially to the ALP's mass during EWSB, thereby modifying
oscillation frequencies during EWSB as well as impacting upon the existing
correlation between the scale of symmetry breaking and their masses. The
novelty of the work lies in broadening the relic satisfied parameter space so
as to probe it in near future via a wide range of experiments.
| [
{
"created": "Thu, 9 Nov 2023 03:41:12 GMT",
"version": "v1"
},
{
"created": "Mon, 6 May 2024 14:13:56 GMT",
"version": "v2"
}
] | 2024-05-07 | [
[
"Manna",
"Soumen Kumar",
""
],
[
"Sil",
"Arunansu",
""
]
] | Axion like particles (ALPs), the pseudo Nambu-Goldstone bosons associated to the spontaneous breaking of global symmetry, have emerged as promising dark matter candidates. Conventionally, in the context of misalignment mechanism, the non-thermally produced ALPs happen to stay frozen due to Hubble friction initially and at a later stage, they begin to oscillate (before matter-radiation equality) at characteristic frequencies defined by their masses and behaving like cold dark matter. In this work, we study the influence of electroweak symmetry breaking (EWSB), through a higher order Higgs portal interaction, on the evolution of ALPs. Such an interaction is found to contribute partially to the ALP's mass during EWSB, thereby modifying oscillation frequencies during EWSB as well as impacting upon the existing correlation between the scale of symmetry breaking and their masses. The novelty of the work lies in broadening the relic satisfied parameter space so as to probe it in near future via a wide range of experiments. |
1210.1323 | Prashant Srivastava Kumar | Ashwini Kumar, B. K. Singh, P. K. Srivastava, and C. P. Singh | Wounded Quarks and Multiplicity at Relativistic Ion Colliders | 10 pages, 10 figures, 5 tables. arXiv admin note: text overlap with
arXiv:1202.4838 | Eur. Phys. J. Plus 128, 45 (2013) | 10.1140/epjp/i2013-13045-9 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we propose a parameterization which is based on a
phenomenological model involving the wounded quarks interactions for explaining
the average charged particle multiplicity $\ < n_{ch}\ >$, the central
pseudo-rapidity density $\ < (dn/d\eta)_{\eta=0}\ >$ and complete rapidity
dependence of $dn/d{\eta}$ in relativistic heavy-ion collider experiments. The
model also interrelates nucleus-nucleus (A-A) collisions with p-A and p-p
interactions. Our parameterization rests on simple assumptions regarding mean
number of participating quarks and their average number of collisions. The
results for $\ < n_{ch}\ >$ and their variations with the mass number of
colliding nuclei, center-of-mass energy ($\sqrt{s_{NN}}$) and collision
centrality are well supported by the available experimental data. Finally we
give the predictions from our model for A-A collisions at the Large Hadron
Collider (LHC) and Compressed Baryonic Matter (CBM) experiments. Our results
indicate the existence of a possible universal production mechanism for p-p,
p-A and A-A collisions.
| [
{
"created": "Thu, 4 Oct 2012 08:06:45 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Apr 2013 06:03:49 GMT",
"version": "v2"
}
] | 2013-04-26 | [
[
"Kumar",
"Ashwini",
""
],
[
"Singh",
"B. K.",
""
],
[
"Srivastava",
"P. K.",
""
],
[
"Singh",
"C. P.",
""
]
] | In this paper, we propose a parameterization which is based on a phenomenological model involving the wounded quarks interactions for explaining the average charged particle multiplicity $\ < n_{ch}\ >$, the central pseudo-rapidity density $\ < (dn/d\eta)_{\eta=0}\ >$ and complete rapidity dependence of $dn/d{\eta}$ in relativistic heavy-ion collider experiments. The model also interrelates nucleus-nucleus (A-A) collisions with p-A and p-p interactions. Our parameterization rests on simple assumptions regarding mean number of participating quarks and their average number of collisions. The results for $\ < n_{ch}\ >$ and their variations with the mass number of colliding nuclei, center-of-mass energy ($\sqrt{s_{NN}}$) and collision centrality are well supported by the available experimental data. Finally we give the predictions from our model for A-A collisions at the Large Hadron Collider (LHC) and Compressed Baryonic Matter (CBM) experiments. Our results indicate the existence of a possible universal production mechanism for p-p, p-A and A-A collisions. |
hep-ph/0001216 | Guy Moore | Guy D. Moore | Sphaleron rate in the symmetric electroweak phase | 23 pages including 4 figures, 2 appendices. Some derivations more
careful and complete, conclusions unchanged | Phys.Rev. D62 (2000) 085011 | 10.1103/PhysRevD.62.085011 | UW/PT 00-01 | hep-ph | null | Recently Bodeker has presented an effective infrared theory for the dynamics
of Yang-Mills theory, suitable for studying the rate of baryon number violation
in the early universe. We extend his theory to include Higgs fields, and study
how much the Higgs affects the baryon number violation rate in the symmetric
phase, at the phase coexistence temperature of a first order electroweak phase
transition. The rate is about 20% smaller than in pure Yang-Mills theory. We
also analyze the sphaleron rate in the analytic crossover regime. Our treatment
relies on the ergodicity conjecture for 3-D scalar $\phi^4$ theory.
| [
{
"created": "Thu, 20 Jan 2000 20:09:57 GMT",
"version": "v1"
},
{
"created": "Tue, 16 May 2000 18:15:49 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Moore",
"Guy D.",
""
]
] | Recently Bodeker has presented an effective infrared theory for the dynamics of Yang-Mills theory, suitable for studying the rate of baryon number violation in the early universe. We extend his theory to include Higgs fields, and study how much the Higgs affects the baryon number violation rate in the symmetric phase, at the phase coexistence temperature of a first order electroweak phase transition. The rate is about 20% smaller than in pure Yang-Mills theory. We also analyze the sphaleron rate in the analytic crossover regime. Our treatment relies on the ergodicity conjecture for 3-D scalar $\phi^4$ theory. |
1203.2183 | Christopher W. Murphy | Benjam\'in Grinstein, Christopher W. Murphy, David Pirtskhalava and
Patipan Uttayarat | Massive Spin-2 States as the Origin of the Top Quark Forward-Backward
Asymmetry | added discussion of differential observables at the LHC, matches
version accepted for publication in JHEP | JHEP 1208 (2012) 073 | 10.1007/JHEP08(2012)073 | UCSD/PTH 12-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that the anomalously large top quark forward-backward asymmetry
observed by CDF and D\O\, can naturally be accommodated in models with
flavor-violating couplings of a new massive spin-2 state to quarks. Regardless
of its origin, the lowest-order couplings of a spin-2 boson to fermions are
analogous to the coupling of the graviton to energy/momentum, leading to strong
sensitivity of the effects associated with its virtual exchange to the energy
scales at hand. Precisely due to this fact, the observed dependence of the
asymmetry on the $t\bar t$ invariant mass fits nicely into the proposed
framework. In particular, we find a vast parameter space which can lead to the
central value for the observed forward-backward asymmetry in the high mass bin,
while being in accord with all of the existing experimental constraints.
| [
{
"created": "Fri, 9 Mar 2012 21:00:06 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Apr 2012 19:16:18 GMT",
"version": "v2"
},
{
"created": "Mon, 27 Aug 2012 17:45:27 GMT",
"version": "v3"
}
] | 2012-08-28 | [
[
"Grinstein",
"Benjamín",
""
],
[
"Murphy",
"Christopher W.",
""
],
[
"Pirtskhalava",
"David",
""
],
[
"Uttayarat",
"Patipan",
""
]
] | We show that the anomalously large top quark forward-backward asymmetry observed by CDF and D\O\, can naturally be accommodated in models with flavor-violating couplings of a new massive spin-2 state to quarks. Regardless of its origin, the lowest-order couplings of a spin-2 boson to fermions are analogous to the coupling of the graviton to energy/momentum, leading to strong sensitivity of the effects associated with its virtual exchange to the energy scales at hand. Precisely due to this fact, the observed dependence of the asymmetry on the $t\bar t$ invariant mass fits nicely into the proposed framework. In particular, we find a vast parameter space which can lead to the central value for the observed forward-backward asymmetry in the high mass bin, while being in accord with all of the existing experimental constraints. |
hep-ph/9608433 | Sourendu Gupta | Sourendu Gupta and K. Sridhar | Colour-octet Contributions to $x_F$ Distributions in $J/\psi$
Hadro-production at Fixed Target Energies | LaTeX source; giving 18 pages including 5 figures; minor changes in
text | Phys.Rev. D55 (1997) 2650-2656 | 10.1103/PhysRevD.55.2650 | TIFR/TH/96-48 | hep-ph | null | We study J/\psi production at fixed-target energies, including the
colour-octet production mechanisms predicted by NRQCD. In an earlier paper, we
found that the octet components were crucial in understanding p_T-integrated
forward (x_F > 0) cross-sections. Here we make a detailed comparison of the
theoretical predictions with measured x_F distributions from fixed-target
experiments. We find that the model predictions agree well with data. Taking
into account higher orders in NRQCD, we argue that
sigma(chi_1)/sigma(chi_2)=0.6, in excellent agreement with data. Similiar
arguments also predict that sigma(chi)/sigma(J/psi) is roughly equal in photo-
and hadro-production.
| [
{
"created": "Sat, 24 Aug 1996 23:24:01 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Sep 1996 15:22:41 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Gupta",
"Sourendu",
""
],
[
"Sridhar",
"K.",
""
]
] | We study J/\psi production at fixed-target energies, including the colour-octet production mechanisms predicted by NRQCD. In an earlier paper, we found that the octet components were crucial in understanding p_T-integrated forward (x_F > 0) cross-sections. Here we make a detailed comparison of the theoretical predictions with measured x_F distributions from fixed-target experiments. We find that the model predictions agree well with data. Taking into account higher orders in NRQCD, we argue that sigma(chi_1)/sigma(chi_2)=0.6, in excellent agreement with data. Similiar arguments also predict that sigma(chi)/sigma(J/psi) is roughly equal in photo- and hadro-production. |
1807.00921 | Xing-Bo Yuan | Jin-Jun Zhang, Min He, Xiao-Gang He, and Xing-Bo Yuan | Flavor Violating Higgs Couplings in Minimal Flavor Violation | 26 pages, 5 figures, minor errors corrected, figures slightly
changed, comments and references added | null | 10.1007/JHEP02(2019)007 | NCTS-PH/1810 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the rencent LHC data on the lepton-flavor violating (LFV) decays
$h\to \ell_1 \ell_2$ and $B_{s,d}\to \ell_1 \ell_2$, we study the
Higgs-mediated flavor-changing neutral current (FCNC) interactions in the
effective field theory (EFT) approach without and with the minimal flavor
violation (MFV) hypothesis, and concentrate on the later. After considering the
$B$ and $K$ physics data, the various LFV processes, and the LHC Higgs data,
severe constraints on the Higgs FCNC couplings are derived, which are dominated
by the LHC Higgs data, the $B_s - \bar B_s$ mixing, and the $\mu \to e \gamma$
decay. In the general case and the MFV framework, allowed ranges of various
observables are obtained, such as $\mathcal B (B_s\to \ell_1 \ell_2)$,
$\mathcal B (h\to \ell_1 \ell_2)$, $\mathcal B (h\to q_1 q_2)$, and the
branching ratio of $\mu \to e$ conversion in Al. Future prospects of searching
for the Higgs FCNC interactions at the low-energy experiments and the LHC are
discussed.
| [
{
"created": "Mon, 2 Jul 2018 23:19:31 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Jul 2018 19:37:06 GMT",
"version": "v2"
}
] | 2019-02-20 | [
[
"Zhang",
"Jin-Jun",
""
],
[
"He",
"Min",
""
],
[
"He",
"Xiao-Gang",
""
],
[
"Yuan",
"Xing-Bo",
""
]
] | Motivated by the rencent LHC data on the lepton-flavor violating (LFV) decays $h\to \ell_1 \ell_2$ and $B_{s,d}\to \ell_1 \ell_2$, we study the Higgs-mediated flavor-changing neutral current (FCNC) interactions in the effective field theory (EFT) approach without and with the minimal flavor violation (MFV) hypothesis, and concentrate on the later. After considering the $B$ and $K$ physics data, the various LFV processes, and the LHC Higgs data, severe constraints on the Higgs FCNC couplings are derived, which are dominated by the LHC Higgs data, the $B_s - \bar B_s$ mixing, and the $\mu \to e \gamma$ decay. In the general case and the MFV framework, allowed ranges of various observables are obtained, such as $\mathcal B (B_s\to \ell_1 \ell_2)$, $\mathcal B (h\to \ell_1 \ell_2)$, $\mathcal B (h\to q_1 q_2)$, and the branching ratio of $\mu \to e$ conversion in Al. Future prospects of searching for the Higgs FCNC interactions at the low-energy experiments and the LHC are discussed. |
2403.09325 | Helen Meyer | Helen Meyer, Ulf-G. Mei{\ss}ner | Improved Constraints on the Variation of the Weak Scale from Big Bang
Nucleosynthesis | Now final version as published in JHEP | J. High Energ. Phys. 2024, 74 (2024) | 10.1007/JHEP06(2024)074 | null | hep-ph astro-ph.CO hep-lat hep-th nucl-th | http://creativecommons.org/licenses/by/4.0/ | We present an improved calculation of the light element abundances in the
framework of Big Bang nucleosynthesis as a function of the Higgs vacuum
expectation value $v$. We compare the methods of our calculation to previous
literature including the recently published work of Burns et al. [1]. The PDG
result for the $^4$He abundance can be explained within $2\sigma$ by $-0.014
\leq \delta v / v \leq 0.026$, for deuterium we find the constraint $-0.005
\leq \delta v / v \leq -0.001$. These bounds are more stringent than what was
found earlier.
| [
{
"created": "Thu, 14 Mar 2024 12:12:25 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Mar 2024 07:48:05 GMT",
"version": "v2"
},
{
"created": "Mon, 17 Jun 2024 08:12:18 GMT",
"version": "v3"
}
] | 2024-06-18 | [
[
"Meyer",
"Helen",
""
],
[
"Meißner",
"Ulf-G.",
""
]
] | We present an improved calculation of the light element abundances in the framework of Big Bang nucleosynthesis as a function of the Higgs vacuum expectation value $v$. We compare the methods of our calculation to previous literature including the recently published work of Burns et al. [1]. The PDG result for the $^4$He abundance can be explained within $2\sigma$ by $-0.014 \leq \delta v / v \leq 0.026$, for deuterium we find the constraint $-0.005 \leq \delta v / v \leq -0.001$. These bounds are more stringent than what was found earlier. |
1704.00219 | Masatoshi Yamada | Koji Tsumura, Masatoshi Yamada, Yuya Yamaguchi | Gravitational wave from dark sector with dark pion | 47 pages, 9 figures, references added; version published in JCAP | JCAP07(2017)044 | 10.1088/1475-7516/2017/07/044 | KUNS-2669, EPHOU-17-004 | hep-ph astro-ph.HE gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we investigate the spectra of gravitational waves produced by
chiral symmetry breaking in dark quantum chromodynamics (dQCD) sector. The dark
pion ($\pi$) can be a dark matter candidate as weakly interacting massive
particle (WIMP) or strongly interacting massive particle (SIMP). For a WIMP
scenario, we introduce the dQCD sector coupled to the standard model (SM)
sector with classical scale invariance and investigate the annihilation process
of the dark pion via the $2\pi \to 2\,\text{SM}$ process. For a SIMP scenario,
we investigate the $3\pi \to 2\pi$ annihilation process of the dark pion as a
SIMP using chiral perturbation theory. We find that in the WIMP scenario the
gravitational wave background spectra can be observed by future space
gravitational wave antennas. On the other hand, when the dark pion is the SIMP
dark matter with the constraints for the chiral perturbative limit and
pion-pion scattering cross section, the chiral phase transition becomes
crossover and then the gravitational waves are not produced.
| [
{
"created": "Sat, 1 Apr 2017 19:42:03 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Apr 2017 10:20:50 GMT",
"version": "v2"
},
{
"created": "Fri, 21 Jul 2017 14:12:37 GMT",
"version": "v3"
}
] | 2017-07-27 | [
[
"Tsumura",
"Koji",
""
],
[
"Yamada",
"Masatoshi",
""
],
[
"Yamaguchi",
"Yuya",
""
]
] | In this work, we investigate the spectra of gravitational waves produced by chiral symmetry breaking in dark quantum chromodynamics (dQCD) sector. The dark pion ($\pi$) can be a dark matter candidate as weakly interacting massive particle (WIMP) or strongly interacting massive particle (SIMP). For a WIMP scenario, we introduce the dQCD sector coupled to the standard model (SM) sector with classical scale invariance and investigate the annihilation process of the dark pion via the $2\pi \to 2\,\text{SM}$ process. For a SIMP scenario, we investigate the $3\pi \to 2\pi$ annihilation process of the dark pion as a SIMP using chiral perturbation theory. We find that in the WIMP scenario the gravitational wave background spectra can be observed by future space gravitational wave antennas. On the other hand, when the dark pion is the SIMP dark matter with the constraints for the chiral perturbative limit and pion-pion scattering cross section, the chiral phase transition becomes crossover and then the gravitational waves are not produced. |
0902.2539 | Pasquale Dario Serpico | Pasquale Dario Serpico, Dan Hooper | Gamma rays from Dark Matter Annihilation in the Central Region of the
Galaxy | v3: corrected typos, content unchanged | New J. Phys.11:105010, 2009 | 10.1088/1367-2630/11/10/105010 | CERN-PH-TH/2009-025, FERMILAB-PUB-09-045-A | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we review the prospects for the Fermi satellite (formerly
known as GLAST) to detect gamma rays from dark matter annihilations in the
Central Region of the Milky Way, in particular on the light of the recent
astrophysical observations and discoveries of Imaging Atmospheric Cherenkov
Telescopes. While the existence of significant backgrounds in this part of the
sky limits Fermi's discovery potential to some degree, this can be mitigated by
exploiting the peculiar energy spectrum and angular distribution of the dark
matter annihilation signal relative to those of astrophysical backgrounds.
| [
{
"created": "Mon, 16 Feb 2009 15:03:35 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Oct 2009 21:01:56 GMT",
"version": "v2"
},
{
"created": "Fri, 25 Jun 2010 05:55:21 GMT",
"version": "v3"
}
] | 2015-03-13 | [
[
"Serpico",
"Pasquale Dario",
""
],
[
"Hooper",
"Dan",
""
]
] | In this article, we review the prospects for the Fermi satellite (formerly known as GLAST) to detect gamma rays from dark matter annihilations in the Central Region of the Milky Way, in particular on the light of the recent astrophysical observations and discoveries of Imaging Atmospheric Cherenkov Telescopes. While the existence of significant backgrounds in this part of the sky limits Fermi's discovery potential to some degree, this can be mitigated by exploiting the peculiar energy spectrum and angular distribution of the dark matter annihilation signal relative to those of astrophysical backgrounds. |
hep-ph/0610198 | Alexei Smirnov Yu | A. Yu. Smirnov | Neutrino oscillations: what is magic about the "magic" baseline? | LaTeX, 12 pages, no figures; discussions of 1-3 mixing corrections
and effects in non-uniform medium are substantially expanded; typos corrected | null | null | null | hep-ph hep-ex | null | Physics interpretation of the ``magic'' baseline, $L_{magic}$, that can play
important role in future oscillation experiments is given. The ``magic''
baseline coincides with the refraction length, $l_0$. The latter, in turn,
approximately equals the oscillation length in matter at high energies.
Therefore at the baseline $L = l_0$ the oscillation phase is $2\pi$, and
consequently, the ``solar'' amplitude of oscillations driven by $\theta_{12}$
and $\Delta m^2_{21}$ vanishes. As a result, in the lowest order (i) the
interference of amplitudes in the $\nu_e - \nu_\mu$ $(\nu_\tau)$ transition
probability is absent; (ii) dependence of the probability on the CP-phase,
$\delta$, as well as on $\theta_{12}$ and $\Delta m^2_{21}$ disappears.
Corrections to the equality $L_{magic} = l_0$ are estimated. Effect of changing
density is considered and two new magic trajectories are identified for
neutrinos that cross the core of the Earth. Other magic baselines associated
with zeros of the atmospheric amplitude are discussed.
| [
{
"created": "Mon, 16 Oct 2006 15:12:02 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Oct 2006 18:09:53 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Smirnov",
"A. Yu.",
""
]
] | Physics interpretation of the ``magic'' baseline, $L_{magic}$, that can play important role in future oscillation experiments is given. The ``magic'' baseline coincides with the refraction length, $l_0$. The latter, in turn, approximately equals the oscillation length in matter at high energies. Therefore at the baseline $L = l_0$ the oscillation phase is $2\pi$, and consequently, the ``solar'' amplitude of oscillations driven by $\theta_{12}$ and $\Delta m^2_{21}$ vanishes. As a result, in the lowest order (i) the interference of amplitudes in the $\nu_e - \nu_\mu$ $(\nu_\tau)$ transition probability is absent; (ii) dependence of the probability on the CP-phase, $\delta$, as well as on $\theta_{12}$ and $\Delta m^2_{21}$ disappears. Corrections to the equality $L_{magic} = l_0$ are estimated. Effect of changing density is considered and two new magic trajectories are identified for neutrinos that cross the core of the Earth. Other magic baselines associated with zeros of the atmospheric amplitude are discussed. |
hep-ph/0304302 | Manuel Reenders | V. P. Gusynin and M. Reenders | Infrared cutoff dependence of the critical flavor number in
three-dimensional QED | 5 pages, 1 figure (revtex4), final version | Phys.Rev. D68 (2003) 025017 | 10.1103/PhysRevD.68.025017 | null | hep-ph cond-mat hep-lat | null | We solve, analytically and numerically, a gap equation in parity invariant
QED_3 in the presence of an infrared cutoff \mu and derive an expression for
the critical fermion number N_c as a function of \mu. We argue that this
dependence of N_c on the infrared scale might solve the discrepancy between
continuum Schwinger-Dyson equations studies and lattice simulations of QED_3.
| [
{
"created": "Wed, 30 Apr 2003 19:37:41 GMT",
"version": "v1"
},
{
"created": "Thu, 1 May 2003 17:15:50 GMT",
"version": "v2"
},
{
"created": "Wed, 30 Jul 2003 14:53:54 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Gusynin",
"V. P.",
""
],
[
"Reenders",
"M.",
""
]
] | We solve, analytically and numerically, a gap equation in parity invariant QED_3 in the presence of an infrared cutoff \mu and derive an expression for the critical fermion number N_c as a function of \mu. We argue that this dependence of N_c on the infrared scale might solve the discrepancy between continuum Schwinger-Dyson equations studies and lattice simulations of QED_3. |
hep-ph/0305267 | Robert Fleischer | Robert Fleischer (CERN) | Exploring CP Violation through B Decays | 22 pages, 4 figures, invited brief review for Modern Physics Letters
A | Mod.Phys.Lett.A18:1413-1434,2003 | 10.1142/S0217732303011162 | CERN-TH/2003-115 | hep-ph | null | The B-meson system provides many strategies to perform stringent tests of the
Standard-Model description of CP violation. In this brief review, we discuss
implications of the currently available B-factory data on the angles alpha,
beta and gamma of the unitarity triangle, emphasize the importance of Bs
studies at hadronic B experiments, and discuss new, theoretically clean
strategies to determine gamma.
| [
{
"created": "Fri, 23 May 2003 15:35:38 GMT",
"version": "v1"
}
] | 2010-11-23 | [
[
"Fleischer",
"Robert",
"",
"CERN"
]
] | The B-meson system provides many strategies to perform stringent tests of the Standard-Model description of CP violation. In this brief review, we discuss implications of the currently available B-factory data on the angles alpha, beta and gamma of the unitarity triangle, emphasize the importance of Bs studies at hadronic B experiments, and discuss new, theoretically clean strategies to determine gamma. |
1308.2052 | Avijit K. Ganguly | Avijit K. Ganguly, Manoj K. Jaiswal and Shikha Awasthi | Signatures Of Scalar Photon Interaction In Astrophysical Situations | Minor modifications, references added, 20 pages, 4 figures | null | null | BHU/MMV/TP/07/08/2013 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dimension-5 photon ($\gamma$) scalar ($\phi$) interaction terms usually
appear in the Lagrangian of bosonic sector of unified theories of
electromagnetism and gravity. This interaction makes the medium dichoric and
induces optical activity. We have modelled the propagation of photons with this
interaction in the environment of cold a magnetized compact star (White Dwarf
(WD) or Neutron Star (NS)), assuming synchro-curvature process as the dominant
mechanism of emission. We have tried to outline the polarimetric implications
of photon-scalar coupling on the produced spectrum of these emissions in the
stellar atmosphere. Further more assuming the 'emission-energy vs
emission-altitude' relation, that is believed to hold in such (i.e. cold
magnetized WD or NS) environments, we have tried to point out the possible
modifications to the radiation spectrum when the same is incorporated along
with dim-5 photon scalar mixing operator.
| [
{
"created": "Fri, 9 Aug 2013 08:39:08 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Aug 2013 13:05:07 GMT",
"version": "v2"
}
] | 2013-08-22 | [
[
"Ganguly",
"Avijit K.",
""
],
[
"Jaiswal",
"Manoj K.",
""
],
[
"Awasthi",
"Shikha",
""
]
] | Dimension-5 photon ($\gamma$) scalar ($\phi$) interaction terms usually appear in the Lagrangian of bosonic sector of unified theories of electromagnetism and gravity. This interaction makes the medium dichoric and induces optical activity. We have modelled the propagation of photons with this interaction in the environment of cold a magnetized compact star (White Dwarf (WD) or Neutron Star (NS)), assuming synchro-curvature process as the dominant mechanism of emission. We have tried to outline the polarimetric implications of photon-scalar coupling on the produced spectrum of these emissions in the stellar atmosphere. Further more assuming the 'emission-energy vs emission-altitude' relation, that is believed to hold in such (i.e. cold magnetized WD or NS) environments, we have tried to point out the possible modifications to the radiation spectrum when the same is incorporated along with dim-5 photon scalar mixing operator. |
hep-ph/0405012 | Georg Kreyerhoff | Saul Barshay, Georg Kreyerhoff and Lalit M. Sehgal | Direct CP Violation in B-+ -> pi-+ omega, pi-+ rho0, pi0 rho-+, and in
B-bar0(B0) -> pi-+ rho+- With an Enhanced Branching Ratio for pi0 rho0 | null | Phys.Lett. B595 (2004) 318-322 | 10.1016/j.physletb.2004.06.062 | null | hep-ph | null | We present a novel dynamics for generating sizable CP-violating asymmetries
in the decays of charged $B^\mp\to \pi^\mp \omega, \pi^\mp\rho^0,
\pi^0\rho^\mp$, and in $\bar{B^0}(B^0)\to\pi^\mp\rho^\pm$. The dynamics for the
necessary final-state interactions involves the mixing of G-parity eigenstates
of the system $(\bar{D}^*D,D^*\ol{D})$ with the $G=\pm 1$ states of $\pi\omega$
and $\pi\rho$, respectively. The dynamical effect is enhanced by the
empirically large branching ratio for decays to $(\bar{D}^*D,D^*\bar{D})$. A
correlated result is a markedly enhanced branching ratio for
$\bar{B^0}(B^0)\to\pi^0\rho^0$, which has now been observed in two experiments.
| [
{
"created": "Mon, 3 May 2004 17:57:34 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Barshay",
"Saul",
""
],
[
"Kreyerhoff",
"Georg",
""
],
[
"Sehgal",
"Lalit M.",
""
]
] | We present a novel dynamics for generating sizable CP-violating asymmetries in the decays of charged $B^\mp\to \pi^\mp \omega, \pi^\mp\rho^0, \pi^0\rho^\mp$, and in $\bar{B^0}(B^0)\to\pi^\mp\rho^\pm$. The dynamics for the necessary final-state interactions involves the mixing of G-parity eigenstates of the system $(\bar{D}^*D,D^*\ol{D})$ with the $G=\pm 1$ states of $\pi\omega$ and $\pi\rho$, respectively. The dynamical effect is enhanced by the empirically large branching ratio for decays to $(\bar{D}^*D,D^*\bar{D})$. A correlated result is a markedly enhanced branching ratio for $\bar{B^0}(B^0)\to\pi^0\rho^0$, which has now been observed in two experiments. |
hep-ph/0403276 | Utpal Sarkar | Utpal Sarkar | Parity in left-right symmetric models | 14 pages latex file; corrected and rewritten introduction | Phys.Lett. B594 (2004) 308-314 | 10.1016/j.physletb.2004.05.041 | null | hep-ph | null | We considered parity breaking in some left-right symmetric models. We studied
spontaneous and explicit parity violation in two cases with doublet and triplet
Higgs scalars. The minimization condition in these two cases differ
significantly. A comparative study of these models is presented emphasizing
their phenomenological consequences.
| [
{
"created": "Sun, 28 Mar 2004 15:17:12 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Apr 2004 19:35:37 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Sarkar",
"Utpal",
""
]
] | We considered parity breaking in some left-right symmetric models. We studied spontaneous and explicit parity violation in two cases with doublet and triplet Higgs scalars. The minimization condition in these two cases differ significantly. A comparative study of these models is presented emphasizing their phenomenological consequences. |
2009.14218 | Aliki Litsa | Aliki Litsa, Katherine Freese, Evangelos I. Sfakianakis, Patrick
Stengel, Luca Visinelli | Large Density Perturbations from Reheating to Standard Model particles
due to the Dynamics of the Higgs Boson during Inflation | 24 pages, 10 figures, references added, minor changes | Phys. Rev. D 104 12, 123546 (2021) | 10.1103/PhysRevD.104.123546 | UT-03-2020; UTTG-11-2020; Nikhef 2020-029; NORDITA-2020-082 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Cosmic Microwave Background (CMB) observations are used to constrain
reheating to Standard Model (SM) particles after a period of inflation. As a
light spectator field, the SM Higgs boson acquires large field values from its
quantum fluctuations during inflation, gives masses to SM particles that vary
from one Hubble patch to another, and thereby produces large density
fluctuations. We consider both perturbative and resonant decay of the inflaton
to SM particles. For the case of perturbative decay from coherent oscillations
of the inflaton after high scale inflation, we find strong constraints on the
reheat temperature for the inflaton decay into heavy SM particles. For the case
of resonant particle production (preheating) to (Higgsed) SM gauge bosons, we
find temperature fluctuations larger than observed in the CMB for a range of
gauge coupling that includes those found in the SM and conclude that such
preheating cannot be the main source of reheating the Universe after inflation.
| [
{
"created": "Tue, 29 Sep 2020 18:00:04 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Dec 2020 15:56:02 GMT",
"version": "v2"
}
] | 2022-11-17 | [
[
"Litsa",
"Aliki",
""
],
[
"Freese",
"Katherine",
""
],
[
"Sfakianakis",
"Evangelos I.",
""
],
[
"Stengel",
"Patrick",
""
],
[
"Visinelli",
"Luca",
""
]
] | Cosmic Microwave Background (CMB) observations are used to constrain reheating to Standard Model (SM) particles after a period of inflation. As a light spectator field, the SM Higgs boson acquires large field values from its quantum fluctuations during inflation, gives masses to SM particles that vary from one Hubble patch to another, and thereby produces large density fluctuations. We consider both perturbative and resonant decay of the inflaton to SM particles. For the case of perturbative decay from coherent oscillations of the inflaton after high scale inflation, we find strong constraints on the reheat temperature for the inflaton decay into heavy SM particles. For the case of resonant particle production (preheating) to (Higgsed) SM gauge bosons, we find temperature fluctuations larger than observed in the CMB for a range of gauge coupling that includes those found in the SM and conclude that such preheating cannot be the main source of reheating the Universe after inflation. |
1007.0596 | Yang Bai | Yang Bai and Ann E. Nelson | CP Violating Contribution to Delta Gamma in the B_s System from Mixing
with a Hidden Pseudoscalar | 18 pages, 4 figures, 2 tables | Phys.Rev.D82:114027,2010 | 10.1103/PhysRevD.82.114027 | FERMILAB-PUB-10-209-T | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent evidence for a CP violating asymmetry in the semileptonic decays of
B_s mesons cannot be accommodated within the Standard Model. Such an asymmetry
can be explained by new physics contributions to Delta B=2 components of either
the mass matrix or the decay matrix. We show that mixing with a hidden
pseudoscalar meson with a mass around 5 GeV can result in a new CP violating
contribution to the mixing and can resolve several anomalies in this system
including the width difference, the average width and the charge asymmetry. We
also discuss the effects of the hidden meson on other b physics observables,
and present viable decay modes for the hidden meson. We make predictions for
new decay channels of B hadrons, which can be tested at the Tevatron, the LHC
and B-factories.
| [
{
"created": "Sun, 4 Jul 2010 22:51:34 GMT",
"version": "v1"
}
] | 2011-02-02 | [
[
"Bai",
"Yang",
""
],
[
"Nelson",
"Ann E.",
""
]
] | Recent evidence for a CP violating asymmetry in the semileptonic decays of B_s mesons cannot be accommodated within the Standard Model. Such an asymmetry can be explained by new physics contributions to Delta B=2 components of either the mass matrix or the decay matrix. We show that mixing with a hidden pseudoscalar meson with a mass around 5 GeV can result in a new CP violating contribution to the mixing and can resolve several anomalies in this system including the width difference, the average width and the charge asymmetry. We also discuss the effects of the hidden meson on other b physics observables, and present viable decay modes for the hidden meson. We make predictions for new decay channels of B hadrons, which can be tested at the Tevatron, the LHC and B-factories. |
2003.05866 | Alexander Korchin | A.Yu. Korchin, V.A. Kovalchuk | Angular distribution and asymmetries in the decay of the polarized
charmed baryon $\Lambda_c^+ \to K^- \, \Delta^{++} \to K^- \, p \, \pi^+$ | 12 pages, 2 figures, ws-ijmpa style; v2: a few references added,
section 3.2 extended, published version | Int. J. Mod. Phys. A 35, no. 11n12, 2050060 (2020) | 10.1142/S0217751X20500608 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Angular distribution of the final particles in the decay $\Lambda_c^+\to K^-
\, \Delta (1232)^{++} \to K^- \, p \, \pi^+$ of the polarized charmed baryon is
discussed. Asymmetries are proposed which allow for determination of the
components of the $\Lambda_c^+$ polarization vector. The precession angle of
the polarization in the process of baryon channeling in a bent crystal is
directly related to these asymmetries. The decay rate and asymmetry parameter
for the $\Lambda_c^+\to K^- \, \Delta (1232)^{++}$ decay are calculated in the
pole model and compared with experiment.
| [
{
"created": "Thu, 12 Mar 2020 15:57:22 GMT",
"version": "v1"
},
{
"created": "Fri, 22 May 2020 07:08:43 GMT",
"version": "v2"
}
] | 2020-05-25 | [
[
"Korchin",
"A. Yu.",
""
],
[
"Kovalchuk",
"V. A.",
""
]
] | Angular distribution of the final particles in the decay $\Lambda_c^+\to K^- \, \Delta (1232)^{++} \to K^- \, p \, \pi^+$ of the polarized charmed baryon is discussed. Asymmetries are proposed which allow for determination of the components of the $\Lambda_c^+$ polarization vector. The precession angle of the polarization in the process of baryon channeling in a bent crystal is directly related to these asymmetries. The decay rate and asymmetry parameter for the $\Lambda_c^+\to K^- \, \Delta (1232)^{++}$ decay are calculated in the pole model and compared with experiment. |
hep-ph/0203093 | Sechul Oh | C.S. Kim, Jake Lee, Sechul Oh, J.S. Hong, D.Y. Kim, and H.S. Kim | A study of semi-inclusive charmless $B \to \pi X$ decays | 18 pages, 7 figures; Revtex; version accepted for publication in Eur.
Phys. J. C | Eur.Phys.J.C25:413-419,2002 | 10.1007/s10052-002-1020-0 | null | hep-ph | null | We study semi-inclusive charmless decays $B \to \pi X$ in detail, such as
$\bar B^0 \to \pi^{\pm (0)} X$, $B^0 \to \pi^{\pm (0)} X$, $B^{\pm} \to
\pi^{\pm (0)} X$, where $X$ does not contain a charm (anti)quark. We find that
the process $\bar B^0 \to \pi^- X$ ($B^0 \to \pi^+ X$) can be particularly
useful for determination of the CKM matrix element $|V_{ub}|$. We calculate and
present the branching ratio (BR) of $\bar B^0 \to \pi^- X$ as a function of
$|V_{ub}|$, with an estimate of possible uncertainties. It is expected that the
BR is an order of $10^{-4}$. Our estimation indicates that one can
phenomenologically determine $|V_{ub}|$ with reasonable accuracy by measuring
the BR of $\bar B^0 \to \pi^- X$ ($B^0 \to \pi^+ X$).
| [
{
"created": "Sat, 9 Mar 2002 08:10:27 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Jul 2002 11:43:11 GMT",
"version": "v2"
}
] | 2011-09-13 | [
[
"Kim",
"C. S.",
""
],
[
"Lee",
"Jake",
""
],
[
"Oh",
"Sechul",
""
],
[
"Hong",
"J. S.",
""
],
[
"Kim",
"D. Y.",
""
],
[
"Kim",
"H. S.",
""
]
] | We study semi-inclusive charmless decays $B \to \pi X$ in detail, such as $\bar B^0 \to \pi^{\pm (0)} X$, $B^0 \to \pi^{\pm (0)} X$, $B^{\pm} \to \pi^{\pm (0)} X$, where $X$ does not contain a charm (anti)quark. We find that the process $\bar B^0 \to \pi^- X$ ($B^0 \to \pi^+ X$) can be particularly useful for determination of the CKM matrix element $|V_{ub}|$. We calculate and present the branching ratio (BR) of $\bar B^0 \to \pi^- X$ as a function of $|V_{ub}|$, with an estimate of possible uncertainties. It is expected that the BR is an order of $10^{-4}$. Our estimation indicates that one can phenomenologically determine $|V_{ub}|$ with reasonable accuracy by measuring the BR of $\bar B^0 \to \pi^- X$ ($B^0 \to \pi^+ X$). |
0902.3645 | Leonard Lesniak | B. El-Bennich, A. Furman, R. Kaminski, L. Lesniak, B. Loiseau, B.
Moussallam | CP violation and kaon-pion interactions in B --> K pi+ pi- decays | 56 pages, 15 figures | Phys.Rev.D79:094005,2009; Erratum-ibid.D83:039903,2011 | 10.1103/PhysRevD.79.094005 10.1103/PhysRevD.83.039903 | LPNHE 2009-02 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study CP violation and the contribution of the strong kaon-pion
interactions in the three body B --> K pi+ pi- decays. We extend our recent
work on the effect of the two-pion S- and P-wave interactions to that of the
corresponding kaon-pion ones. The weak amplitudes have a first term derived in
QCD factorization and a second one as a phenomenological contribution added to
the QCD penguin amplitudes. The effective QCD coefficients include the leading
order contributions plus next-to-leading order vertex and penguins corrections.
The matrix elements of the transition to the vacuum of the kaon-pion pairs,
appearing naturally in the factorization formulation, are described by the
strange K pi scalar (S-wave) and vector (P-wave) form factors. These are
determined from Muskhelishvili-Omnes coupled channel equations using
experimental kaon-pion T-matrix elements, together with chiral symmetry and
asymptotic QCD constraints. From the scalar form factor study, the modulus of
the K*_0(1430) decay constant is found to be (32 +/- 5) MeV. The additional
phenomenological amplitudes are fitted to reproduce the K pi effective mass and
helicity angle distributions, the B --> K*(892) pi branching ratios and the CP
asymmetries of the recent data from Belle and BaBar collaborations. We use also
the new measurement by the BaBar group of the phase difference between the B0
and B0bar decay amplitudes to K*(892) pi. Our predicted B+/- --> K*_0(1430)
pi+/-, K*_0(1430) --> K+/- pi-\+ branching fraction, (11.6 +/- 0.6) 10^{-6}, is
smaller than the result of the analyzes of both collaborations. For the neutral
B0 decays, the predicted value is (11.1 +- 0.5) 10^{-6}. In order to reduce the
large systematic uncertainties in the experimental determination of the B -->
K*_0(1430) pi branching fractions, a new parametrization is proposed.
| [
{
"created": "Fri, 20 Feb 2009 19:23:05 GMT",
"version": "v1"
},
{
"created": "Sat, 21 Feb 2009 02:30:09 GMT",
"version": "v2"
}
] | 2011-03-23 | [
[
"El-Bennich",
"B.",
""
],
[
"Furman",
"A.",
""
],
[
"Kaminski",
"R.",
""
],
[
"Lesniak",
"L.",
""
],
[
"Loiseau",
"B.",
""
],
[
"Moussallam",
"B.",
""
]
] | We study CP violation and the contribution of the strong kaon-pion interactions in the three body B --> K pi+ pi- decays. We extend our recent work on the effect of the two-pion S- and P-wave interactions to that of the corresponding kaon-pion ones. The weak amplitudes have a first term derived in QCD factorization and a second one as a phenomenological contribution added to the QCD penguin amplitudes. The effective QCD coefficients include the leading order contributions plus next-to-leading order vertex and penguins corrections. The matrix elements of the transition to the vacuum of the kaon-pion pairs, appearing naturally in the factorization formulation, are described by the strange K pi scalar (S-wave) and vector (P-wave) form factors. These are determined from Muskhelishvili-Omnes coupled channel equations using experimental kaon-pion T-matrix elements, together with chiral symmetry and asymptotic QCD constraints. From the scalar form factor study, the modulus of the K*_0(1430) decay constant is found to be (32 +/- 5) MeV. The additional phenomenological amplitudes are fitted to reproduce the K pi effective mass and helicity angle distributions, the B --> K*(892) pi branching ratios and the CP asymmetries of the recent data from Belle and BaBar collaborations. We use also the new measurement by the BaBar group of the phase difference between the B0 and B0bar decay amplitudes to K*(892) pi. Our predicted B+/- --> K*_0(1430) pi+/-, K*_0(1430) --> K+/- pi-\+ branching fraction, (11.6 +/- 0.6) 10^{-6}, is smaller than the result of the analyzes of both collaborations. For the neutral B0 decays, the predicted value is (11.1 +- 0.5) 10^{-6}. In order to reduce the large systematic uncertainties in the experimental determination of the B --> K*_0(1430) pi branching fractions, a new parametrization is proposed. |
hep-ph/9805353 | Kotikov A. V. | A. V. Kotikov, V. G. Krivokhijine (JINR, Dubna) | F_2 Structure Function and Higher-twist Contributons (Nonsinglet Case) | 4 pages, latex. Talk presented at the DIS98 workshop, Brussels, April
1998 | null | null | null | hep-ph | null | We performed the combine fits of SLAC, BCDMS and NMC data at NLO level. The
data are fitted very well with different parametrizations of higher twist
contributions. The theory-based parametrizations lead to the low values of QCD
parameter \Lambda^{f=4}_{\overfull{MS}} \sim 140 \pm 21 MeV (or
\alpha_s(M^2_Z)= 0.103 \pm 0.002).
| [
{
"created": "Mon, 18 May 1998 11:23:15 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Jun 1998 16:20:56 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Kotikov",
"A. V.",
"",
"JINR, Dubna"
],
[
"Krivokhijine",
"V. G.",
"",
"JINR, Dubna"
]
] | We performed the combine fits of SLAC, BCDMS and NMC data at NLO level. The data are fitted very well with different parametrizations of higher twist contributions. The theory-based parametrizations lead to the low values of QCD parameter \Lambda^{f=4}_{\overfull{MS}} \sim 140 \pm 21 MeV (or \alpha_s(M^2_Z)= 0.103 \pm 0.002). |
hep-ph/9606377 | Ramon Toldra. Ifae | J.A. Grifols, E. Masso and R. Toldra | Majorana Neutrinos and Long Range Forces | 7 pages, Latex, 1 postcript figure. False statement about neutrino
bounding in neutron stars mended | Phys.Lett. B389 (1996) 563-565 | 10.1016/S0370-2693(96)01304-4 | UAB-FT-394 | hep-ph | null | We establish that forces mediated by the exchange of a pair of Majorana
neutrinos differ from those due to Dirac neutrino exchange.
| [
{
"created": "Wed, 19 Jun 1996 15:49:00 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Jul 1996 17:02:09 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Grifols",
"J. A.",
""
],
[
"Masso",
"E.",
""
],
[
"Toldra",
"R.",
""
]
] | We establish that forces mediated by the exchange of a pair of Majorana neutrinos differ from those due to Dirac neutrino exchange. |
0905.1198 | Tanguy Pierog | T. Pierog and K. Werner | EPOS Model and Ultra High Energy Cosmic Rays | 4 pages, 6 figures, To be published in the proceedings of the XVth
ISVHECRI, Paris, 2008 | Nucl.Phys.Proc.Suppl.196:102-105,2009 | 10.1016/j.nuclphysbps.2009.09.017 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Interpretation of extensive air showers (EAS) experiments results is strongly
based on air shower simulations. The latter being based on hadronic interaction
models, any new model can help for the understanding of the nature of cosmic
rays. The EPOS model reproducing all major results of existing accelerator data
(including detailed data of RHIC experiments) has been introduced in air shower
simulation programs CORSIKA and CONEX few years ago. The new EPOS 1.99 has
recently been updated taking into account the problem seen in EAS development
using EPOS 1.61. We will show in details the relationship between some EPOS
hadronic properties and EAS development, as well as the consequences on the
model and finally on cosmic ray analysis.
| [
{
"created": "Fri, 8 May 2009 08:13:25 GMT",
"version": "v1"
}
] | 2009-12-08 | [
[
"Pierog",
"T.",
""
],
[
"Werner",
"K.",
""
]
] | Interpretation of extensive air showers (EAS) experiments results is strongly based on air shower simulations. The latter being based on hadronic interaction models, any new model can help for the understanding of the nature of cosmic rays. The EPOS model reproducing all major results of existing accelerator data (including detailed data of RHIC experiments) has been introduced in air shower simulation programs CORSIKA and CONEX few years ago. The new EPOS 1.99 has recently been updated taking into account the problem seen in EAS development using EPOS 1.61. We will show in details the relationship between some EPOS hadronic properties and EAS development, as well as the consequences on the model and finally on cosmic ray analysis. |
hep-ph/0605012 | Gino Isidori | Gino Isidori, Paride Paradisi | Hints of large tan(beta) in flavour physics | 15 pages, 10 figures; v3: numerical value in Eq.(6) corrected with
respect to publ. version (discussion/conclusions unchanged) | Phys.Lett.B639:499-507,2006 | 10.1016/j.physletb.2006.06.071 | null | hep-ph | null | Motivated by the first evidence of the B -> tau nu transition reported by
Belle and by the precise DeltaM_{B_s} measurement by CDF, we analyse these and
other low-energy observables in the framework of the MSSM at large tan(beta).
We show that for heavy squarks and A terms (M_squarks, A_U > 1 TeV) such
scenario has several interesting virtues. It naturally describes: i) a
suppression of BR(B->tau nu) of (10-40)%, ii) a sizable enhancement of
(g-2)_mu, iii) a heavy SM-like Higgs (m_h ~ 120 GeV), iv) small non-standard
effects in DeltaM_{B_s} and BR(B -> X_s gamma) (in agreement with present
observations). The possibilities to find more convincing evidences of such
scenario, with improved data on BR(B -> tau nu), BR(B -> l+ l-) and other
low-energy observables, are briefly discussed.
| [
{
"created": "Sun, 30 Apr 2006 16:40:16 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Jun 2006 18:02:30 GMT",
"version": "v2"
},
{
"created": "Tue, 19 Jun 2007 13:58:50 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Isidori",
"Gino",
""
],
[
"Paradisi",
"Paride",
""
]
] | Motivated by the first evidence of the B -> tau nu transition reported by Belle and by the precise DeltaM_{B_s} measurement by CDF, we analyse these and other low-energy observables in the framework of the MSSM at large tan(beta). We show that for heavy squarks and A terms (M_squarks, A_U > 1 TeV) such scenario has several interesting virtues. It naturally describes: i) a suppression of BR(B->tau nu) of (10-40)%, ii) a sizable enhancement of (g-2)_mu, iii) a heavy SM-like Higgs (m_h ~ 120 GeV), iv) small non-standard effects in DeltaM_{B_s} and BR(B -> X_s gamma) (in agreement with present observations). The possibilities to find more convincing evidences of such scenario, with improved data on BR(B -> tau nu), BR(B -> l+ l-) and other low-energy observables, are briefly discussed. |
2407.06461 | A. Bashir | I. M. Higuera-Angulo, R. J. Hern\'andez-Pinto, K. Raya, A. Bashir | Electromagnetic and two-photon transition form factors of the
pseudoscalar mesons: An algebraic model computation | 18 pages, 8 Figures | null | null | null | hep-ph hep-th nucl-th | http://creativecommons.org/licenses/by/4.0/ | We compute electromagnetic and two-photon transition form factors of
ground-state pseudoscalar mesons: $\pi,\,K,\,\eta_c,\,\eta_b$. To this end, we
employ an algebraic model based upon the coupled formalism of Schwinger-Dyson
and Bethe-Salpeter equations. Within this approach, the dressed quark
propagator and the relevant Bethe-Salpeter amplitude encode the internal
structure of the corresponding meson. Electromagnetic properties of the meson
are probed via the quark-photon interaction. The algebraic model employed by us
unifies the treatment of all ground-state pseudoscalar mesons. Its parameters
are carefully fitted performing a global analysis of existing experimental data
including the knowledge of the charge radii of the mesons studied. We then
compute and predict electromagnetic and two-photon transition form factors for
a wide range of probing photon momentum-squared which is of direct relevance to
the experimental observations carried out thus far or planned at different
hadron physics facilities such as the Thomas Jefferson National Accelerator
Facility (JLab) and the forthcoming Electron-Ion Collider. We also present
comparisons with other theoretical models and approaches and lattice quantum
chromodynamics.
| [
{
"created": "Mon, 8 Jul 2024 23:49:25 GMT",
"version": "v1"
}
] | 2024-07-10 | [
[
"Higuera-Angulo",
"I. M.",
""
],
[
"Hernández-Pinto",
"R. J.",
""
],
[
"Raya",
"K.",
""
],
[
"Bashir",
"A.",
""
]
] | We compute electromagnetic and two-photon transition form factors of ground-state pseudoscalar mesons: $\pi,\,K,\,\eta_c,\,\eta_b$. To this end, we employ an algebraic model based upon the coupled formalism of Schwinger-Dyson and Bethe-Salpeter equations. Within this approach, the dressed quark propagator and the relevant Bethe-Salpeter amplitude encode the internal structure of the corresponding meson. Electromagnetic properties of the meson are probed via the quark-photon interaction. The algebraic model employed by us unifies the treatment of all ground-state pseudoscalar mesons. Its parameters are carefully fitted performing a global analysis of existing experimental data including the knowledge of the charge radii of the mesons studied. We then compute and predict electromagnetic and two-photon transition form factors for a wide range of probing photon momentum-squared which is of direct relevance to the experimental observations carried out thus far or planned at different hadron physics facilities such as the Thomas Jefferson National Accelerator Facility (JLab) and the forthcoming Electron-Ion Collider. We also present comparisons with other theoretical models and approaches and lattice quantum chromodynamics. |
1203.2932 | David Curtin | David Curtin, Prerit Jaiswal, Patrick Meade | Excluding Electroweak Baryogenesis in the MSSM | 24 Pages, 4 Figures (v3: fixed typos, minor corrections, added
references) | null | 10.1007/JHEP08(2012)005 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the context of the MSSM the Light Stop Scenario (LSS) is the only region
of parameter space that allows for successful Electroweak Baryogenesis (EWBG).
This possibility is very phenomenologically attractive, since it allows for the
direct production of light stops and could be tested at the LHC. The ATLAS and
CMS experiments have recently supplied tantalizing hints for a Higgs boson with
a mass of ~ 125 GeV. This Higgs mass severely restricts the parameter space of
the LSS, and we discuss the specific predictions made for EWBG in the MSSM.
Combining data from all the available ATLAS and CMS Higgs searches reveals a
tension with the predictions of EWBG even at this early stage. This allows us
to exclude EWBG in the MSSM at greater than (90) 95% confidence level in the
(non-)decoupling limit, by examining correlations between different Higgs decay
channels. We also examine the exclusion without the assumption of a ~ 125 GeV
Higgs. The Higgs searches are still highly constraining, excluding the entire
EWBG parameter space at greater than 90% CL except for a small window of m_h ~
117 - 119 GeV.
| [
{
"created": "Tue, 13 Mar 2012 20:02:39 GMT",
"version": "v1"
},
{
"created": "Mon, 9 Apr 2012 15:52:09 GMT",
"version": "v2"
},
{
"created": "Sun, 5 Aug 2012 00:26:27 GMT",
"version": "v3"
}
] | 2015-06-04 | [
[
"Curtin",
"David",
""
],
[
"Jaiswal",
"Prerit",
""
],
[
"Meade",
"Patrick",
""
]
] | In the context of the MSSM the Light Stop Scenario (LSS) is the only region of parameter space that allows for successful Electroweak Baryogenesis (EWBG). This possibility is very phenomenologically attractive, since it allows for the direct production of light stops and could be tested at the LHC. The ATLAS and CMS experiments have recently supplied tantalizing hints for a Higgs boson with a mass of ~ 125 GeV. This Higgs mass severely restricts the parameter space of the LSS, and we discuss the specific predictions made for EWBG in the MSSM. Combining data from all the available ATLAS and CMS Higgs searches reveals a tension with the predictions of EWBG even at this early stage. This allows us to exclude EWBG in the MSSM at greater than (90) 95% confidence level in the (non-)decoupling limit, by examining correlations between different Higgs decay channels. We also examine the exclusion without the assumption of a ~ 125 GeV Higgs. The Higgs searches are still highly constraining, excluding the entire EWBG parameter space at greater than 90% CL except for a small window of m_h ~ 117 - 119 GeV. |
hep-ph/9907460 | null | Nuria Rius and Veronica Sanz | Supersymmetric Electroweak Baryogenesis | 16 pages, LaTeX, 3 ps figures, minor changes added, one reference
added | Nucl.Phys. B570 (2000) 155-173 | 10.1016/S0550-3213(99)00797-X | FTUV/99-48, IFIC/99-50 | hep-ph | null | We calculate the baryon asymmetry generated at the electroweak phase
transition in the minimal supersymmetric standard model, using a new method to
compute the CP-violating asymmetry in the Higgsino flux reflected into the
unbroken phase. The method is based on a Higgs insertion expansion. We find
that the CP asymmetry at leading order is proportional to the change in $\tan
\beta$ in the bubble wall, which is at most of order $10^{-2}$, while at
next-to-leading order this suppression factor disappears. This result may
enhance the final baryon asymmetry generated during the electroweak phase
transition for small $\Delta \beta (< 10^{-3}$).
| [
{
"created": "Thu, 22 Jul 1999 15:30:04 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Aug 1999 07:49:20 GMT",
"version": "v2"
},
{
"created": "Tue, 4 Apr 2000 15:51:01 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Rius",
"Nuria",
""
],
[
"Sanz",
"Veronica",
""
]
] | We calculate the baryon asymmetry generated at the electroweak phase transition in the minimal supersymmetric standard model, using a new method to compute the CP-violating asymmetry in the Higgsino flux reflected into the unbroken phase. The method is based on a Higgs insertion expansion. We find that the CP asymmetry at leading order is proportional to the change in $\tan \beta$ in the bubble wall, which is at most of order $10^{-2}$, while at next-to-leading order this suppression factor disappears. This result may enhance the final baryon asymmetry generated during the electroweak phase transition for small $\Delta \beta (< 10^{-3}$). |
1910.02080 | Raymond Co | Raymond T. Co and Keisuke Harigaya | Axiogenesis | 6+10 pages, 1+2 figures; v2: a simplified model and references added,
matches journal version | Phys. Rev. Lett. 124, 111602 (2020) | 10.1103/PhysRevLett.124.111602 | LCTP-19-27 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a mechanism called axiogenesis where the cosmological excess of
baryons over antibaryons is generated from the rotation of the QCD axion. The
Peccei-Quinn (PQ) symmetry may be explicitly broken in the early universe,
inducing the rotation of a PQ charged scalar field. The rotation corresponds to
the asymmetry of the PQ charge, which is converted into the baryon asymmetry
via QCD and electroweak sphaleron transitions. In the concrete model we
explore, interesting phenomenology arises due to the prediction of a small
decay constant and the connections with new physics at the LHC and future
colliders and with axion dark matter.
| [
{
"created": "Fri, 4 Oct 2019 18:00:01 GMT",
"version": "v1"
},
{
"created": "Tue, 31 Mar 2020 01:56:01 GMT",
"version": "v2"
}
] | 2020-04-01 | [
[
"Co",
"Raymond T.",
""
],
[
"Harigaya",
"Keisuke",
""
]
] | We propose a mechanism called axiogenesis where the cosmological excess of baryons over antibaryons is generated from the rotation of the QCD axion. The Peccei-Quinn (PQ) symmetry may be explicitly broken in the early universe, inducing the rotation of a PQ charged scalar field. The rotation corresponds to the asymmetry of the PQ charge, which is converted into the baryon asymmetry via QCD and electroweak sphaleron transitions. In the concrete model we explore, interesting phenomenology arises due to the prediction of a small decay constant and the connections with new physics at the LHC and future colliders and with axion dark matter. |
2002.00969 | Simon King | Simon J.D. King, Stephen F. King | Fermion Mass Hierarchies from Modular Symmetry | 30 pages, matches version published in JHEP | JHEP 09 (2020) 043 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show how quark and lepton mass hierarchies can be reproduced in the
framework of modular symmetry. The mechanism is analogous to the
Froggatt-Nielsen (FN) mechanism, but without requiring any Abelian symmetry to
be introduced, nor any Standard Model (SM) singlet flavon to break it. The
modular weights of fermion fields play the role of FN charges, and SM singlet
fields with non-zero modular weight called weightons play the role of flavons.
We illustrate the mechanism by analysing $A_4$ (modular level 3) models of
quark and lepton (including neutrino) masses and mixing, with a single modulus
field. We discuss two examples in some detail, both numerically and
analytically, showing how both fermion mass and mixing hierarchies emerge from
different aspects of the modular symmetry.
| [
{
"created": "Mon, 3 Feb 2020 19:00:04 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Sep 2020 10:30:51 GMT",
"version": "v2"
}
] | 2020-09-29 | [
[
"King",
"Simon J. D.",
""
],
[
"King",
"Stephen F.",
""
]
] | We show how quark and lepton mass hierarchies can be reproduced in the framework of modular symmetry. The mechanism is analogous to the Froggatt-Nielsen (FN) mechanism, but without requiring any Abelian symmetry to be introduced, nor any Standard Model (SM) singlet flavon to break it. The modular weights of fermion fields play the role of FN charges, and SM singlet fields with non-zero modular weight called weightons play the role of flavons. We illustrate the mechanism by analysing $A_4$ (modular level 3) models of quark and lepton (including neutrino) masses and mixing, with a single modulus field. We discuss two examples in some detail, both numerically and analytically, showing how both fermion mass and mixing hierarchies emerge from different aspects of the modular symmetry. |
hep-ph/0507304 | A. H. Rezaeian | Amir H. Rezaeian | Topics in quantum field theory: Renormalization groups in Hamiltonian
framework and baryon structure in a non-local QCD model | 158 pages, PhD thesis | null | null | null | hep-ph | null | In this thesis we investigate aspects of two problems. In the first part of
this thesis, we concentrate on renormalization group methods in Hamiltonian
framework. We show that the well-known coupled-cluster many-body theory
techniques can be incorporated in the Wilsonian renormalization group to
provide a very powerful framework for construction of effective Hamiltonian
field theories. Eventhough the formulation is intrinsically non-perturbative,
we have shown that a loop-expansion can be implemented. As illustrative
examples, we apply our formulation on the $\Phi^{4}$ theory and an extended Lee
model. The many-body problem in an extended Lee model is also studied. We show
that a combination of the coupled-cluster theory and the Feshbach projection
techniques leads to a renormalized generalized Brueckner theory. The second
part of the thesis is rather phenomenologically orientated. In this part, we
will employ an effective field-theoretical model as can be constructed by means
of the techniques of the first part of the thesis, a quark-confining non-local
NJL model and study the baryon and diquarks in this model. After truncation of
the two-body channels to the scalar and axial-vector diquarks, a relativistic
Faddeev equation for nucleon bound states is solved in the covariant
diquark-quark picture. We study the possible implications of quark confinement
for the description of the diquarks and the nucleon. We also examine
alternative field theoretical approaches for describing baryons.
| [
{
"created": "Tue, 26 Jul 2005 17:26:14 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Rezaeian",
"Amir H.",
""
]
] | In this thesis we investigate aspects of two problems. In the first part of this thesis, we concentrate on renormalization group methods in Hamiltonian framework. We show that the well-known coupled-cluster many-body theory techniques can be incorporated in the Wilsonian renormalization group to provide a very powerful framework for construction of effective Hamiltonian field theories. Eventhough the formulation is intrinsically non-perturbative, we have shown that a loop-expansion can be implemented. As illustrative examples, we apply our formulation on the $\Phi^{4}$ theory and an extended Lee model. The many-body problem in an extended Lee model is also studied. We show that a combination of the coupled-cluster theory and the Feshbach projection techniques leads to a renormalized generalized Brueckner theory. The second part of the thesis is rather phenomenologically orientated. In this part, we will employ an effective field-theoretical model as can be constructed by means of the techniques of the first part of the thesis, a quark-confining non-local NJL model and study the baryon and diquarks in this model. After truncation of the two-body channels to the scalar and axial-vector diquarks, a relativistic Faddeev equation for nucleon bound states is solved in the covariant diquark-quark picture. We study the possible implications of quark confinement for the description of the diquarks and the nucleon. We also examine alternative field theoretical approaches for describing baryons. |
hep-ph/9508356 | null | Robert S. Plant and Michael C. Birse (University of Manchester) | $\rho\to 4\pi$ in chirally symmetric models | 12 pages (RevTeX) | Phys.Lett. B365 (1996) 292 | 10.1016/0370-2693(95)01273-7 | MC/TH 95/14 | hep-ph | null | The decays $\rho^0\to 2\pi^+2\pi^-$ and $\rho^0\to 2\pi^0\pi^+\pi^-$ are
studied using various effective Lagrangians for $\pi$ and $\rho$ (and in some
cases $a_1$) mesons, all of which respect the approximate chiral symmetry of
the strong interaction. Partial widths of the order of 1 keV or less are found
in all cases. These are an order of magnitude smaller than recent predictions
based on non-chiral models.
| [
{
"created": "Wed, 23 Aug 1995 14:22:58 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Plant",
"Robert S.",
"",
"University of Manchester"
],
[
"Birse",
"Michael C.",
"",
"University of Manchester"
]
] | The decays $\rho^0\to 2\pi^+2\pi^-$ and $\rho^0\to 2\pi^0\pi^+\pi^-$ are studied using various effective Lagrangians for $\pi$ and $\rho$ (and in some cases $a_1$) mesons, all of which respect the approximate chiral symmetry of the strong interaction. Partial widths of the order of 1 keV or less are found in all cases. These are an order of magnitude smaller than recent predictions based on non-chiral models. |
hep-ph/0602140 | Chuan Hung Chen | Chuan-Hung Chen, Hisaki Hatanaka | Nonuniversal $Z^{\prime}$ couplings in B decays | 28 pages, 9 figures, version revised | Phys.Rev.D73:075003,2006 | 10.1103/PhysRevD.73.075003 | null | hep-ph hep-ex | null | We study the impacts of nonuniversal $Z^{\prime}$ model, providing flavor
changing neutral current at tree level, on the branching ratios (BRs), CP
asymmetries (CPAs) and polarization fractions of B decays. We find that for
satisfying the current data, the new left- and right-handed couplings have to
be included at the same time. The new introduced effective interactions not
only could effectively explain the puzzle of small longitudinal polarization in
$B\to K^* \phi$ decays, but also provide a solution to the small CPA of
$B^{\pm}\to \pi^{0} K^{\pm}$. We also find that the favorable CPA of
$B^{\pm}\to \pi^{0} K^{\pm}$ is opposite in sign to the standard model;
meanwhile, the CPA of $B_{d}\to \pi^{0}K$ has to be smaller than -10%. In
addition, by using the values of parameters which are constrained by $B\to \pi
K$, we find that the favorable ranges of BRs, CPAs, longitudinal polarizations,
and perpendicular transverse polarizations for $(B^{\pm}\to \rho^{\pm} K^{*},
B_{d}\to \rho^{\mp} K^{*\pm})$ are $(17.1\pm 3.9, 10.0\pm2.0)\times 10^{-6}$,
$(3\pm 5, 21\pm 7)%$, $(0.66\pm 0.10, 0.44\pm 0.08)$ and $(0.14\pm 0.10,
0.25\pm 0.09)$, respectively.
| [
{
"created": "Wed, 15 Feb 2006 13:24:11 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Apr 2006 13:50:41 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Chen",
"Chuan-Hung",
""
],
[
"Hatanaka",
"Hisaki",
""
]
] | We study the impacts of nonuniversal $Z^{\prime}$ model, providing flavor changing neutral current at tree level, on the branching ratios (BRs), CP asymmetries (CPAs) and polarization fractions of B decays. We find that for satisfying the current data, the new left- and right-handed couplings have to be included at the same time. The new introduced effective interactions not only could effectively explain the puzzle of small longitudinal polarization in $B\to K^* \phi$ decays, but also provide a solution to the small CPA of $B^{\pm}\to \pi^{0} K^{\pm}$. We also find that the favorable CPA of $B^{\pm}\to \pi^{0} K^{\pm}$ is opposite in sign to the standard model; meanwhile, the CPA of $B_{d}\to \pi^{0}K$ has to be smaller than -10%. In addition, by using the values of parameters which are constrained by $B\to \pi K$, we find that the favorable ranges of BRs, CPAs, longitudinal polarizations, and perpendicular transverse polarizations for $(B^{\pm}\to \rho^{\pm} K^{*}, B_{d}\to \rho^{\mp} K^{*\pm})$ are $(17.1\pm 3.9, 10.0\pm2.0)\times 10^{-6}$, $(3\pm 5, 21\pm 7)%$, $(0.66\pm 0.10, 0.44\pm 0.08)$ and $(0.14\pm 0.10, 0.25\pm 0.09)$, respectively. |
hep-ph/0004161 | Vasiliki Mitsou | V.A. Mitsou | Search for new physics with ATLAS at the LHC | 6 pages LaTeX, 4 eps figures and 1 style file incorporated. Presented
at the Lake Louise Winter Institute 2000: From Particles to the Universe,
Alberta, Canada, 20-26 February 2000 | null | 10.1142/9789812811752_0035 | ATL-CONF-2000-002 | hep-ph hep-ex | null | Due to the high energy and luminosity of the LHC, the ATLAS experiment has a
huge discovery potential for new physics. A Standard Model Higgs boson can be
discovered over the full range of allowed masses, and its mass should be
measured with a precision of about 0.1%. The Higgs sector of the MSSM should be
fully explored by searches for supersymmetric Higgs bosons. Squarks and gluinos
can be discovered up to masses of 2.5 TeV and several precision measurements
can be performed in the SUSY sector. The existence of particles predicted by
other theories beyond the Standard Model has been also investigated.
| [
{
"created": "Mon, 17 Apr 2000 11:37:44 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Mitsou",
"V. A.",
""
]
] | Due to the high energy and luminosity of the LHC, the ATLAS experiment has a huge discovery potential for new physics. A Standard Model Higgs boson can be discovered over the full range of allowed masses, and its mass should be measured with a precision of about 0.1%. The Higgs sector of the MSSM should be fully explored by searches for supersymmetric Higgs bosons. Squarks and gluinos can be discovered up to masses of 2.5 TeV and several precision measurements can be performed in the SUSY sector. The existence of particles predicted by other theories beyond the Standard Model has been also investigated. |
2404.02602 | Henry Hirvonen | H. Hirvonen, K.J. Eskola, H. Niemi | Deep learning for flow observables in high energy heavy-ion collisions | 4 pages, 4 figures. Presented at the XXXth International Conference
on Ultra-relativistic Nucleus-Nucleus Collisions (Quark Matter 2023),
Houston, Texas, USA | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We demonstrate how deep convolutional neural networks can be trained to
predict 2+1 D hydrodynamic simulation results for flow coefficients,
mean-transverse-momentum and charged particle multiplicity from the initial
energy density profile. We show that this method provides results that are
accurate enough, so that one can use neural networks to reliably estimate
multi-particle flow correlators. Additionally, we train networks that can take
any model parameter as an additional input and demonstrate with a few examples
that the accuracy remains good. The usage of neural networks can reduce the
computation time needed in performing Bayesian analyses with multi-particle
flow correlators by many orders of magnitude.
| [
{
"created": "Wed, 3 Apr 2024 09:44:45 GMT",
"version": "v1"
}
] | 2024-04-04 | [
[
"Hirvonen",
"H.",
""
],
[
"Eskola",
"K. J.",
""
],
[
"Niemi",
"H.",
""
]
] | We demonstrate how deep convolutional neural networks can be trained to predict 2+1 D hydrodynamic simulation results for flow coefficients, mean-transverse-momentum and charged particle multiplicity from the initial energy density profile. We show that this method provides results that are accurate enough, so that one can use neural networks to reliably estimate multi-particle flow correlators. Additionally, we train networks that can take any model parameter as an additional input and demonstrate with a few examples that the accuracy remains good. The usage of neural networks can reduce the computation time needed in performing Bayesian analyses with multi-particle flow correlators by many orders of magnitude. |
hep-ph/0503107 | Federico Mescia DR | Gino Isidori, Christopher Smith, Federico Mescia | Light-quark Loops in K->pi nu nu | null | Nucl.Phys. B718 (2005) 319-338 | 10.1016/j.nuclphysb.2005.04.008 | RM3-TH/05-2 | hep-ph | null | We present a comprehensive analysis of the contributions to K->pi nu nu
decays not described by the leading dimension-six effective Hamiltonian. These
include both dimension-eight four-fermion operators generated at the charm
scale, and genuine long-distance contributions which can be described within
the framework of chiral perturbation theory. We show that a consistent
treatment of the latter contributions, which turn out to be the dominant
effect, requires the introduction of new chiral operators already at O(GF^2
p^2). Using this new chiral Lagrangian, we analyze the long-distance structure
of K->pi nu nu amplitudes at the one-loop level, and discuss the role of the
dimension-eight operators in the matching between short- and long-distance
components. From the numerical point of view, we find that these O(GF^2
LambdaQCD^2) corrections enhance the SM prediction of Br(K+->pi+ nu nu) by
about 6%
| [
{
"created": "Fri, 11 Mar 2005 17:20:31 GMT",
"version": "v1"
}
] | 2010-04-05 | [
[
"Isidori",
"Gino",
""
],
[
"Smith",
"Christopher",
""
],
[
"Mescia",
"Federico",
""
]
] | We present a comprehensive analysis of the contributions to K->pi nu nu decays not described by the leading dimension-six effective Hamiltonian. These include both dimension-eight four-fermion operators generated at the charm scale, and genuine long-distance contributions which can be described within the framework of chiral perturbation theory. We show that a consistent treatment of the latter contributions, which turn out to be the dominant effect, requires the introduction of new chiral operators already at O(GF^2 p^2). Using this new chiral Lagrangian, we analyze the long-distance structure of K->pi nu nu amplitudes at the one-loop level, and discuss the role of the dimension-eight operators in the matching between short- and long-distance components. From the numerical point of view, we find that these O(GF^2 LambdaQCD^2) corrections enhance the SM prediction of Br(K+->pi+ nu nu) by about 6% |
1810.11336 | Felix Kahlhoefer | Babette D\"obrich, Fatih Ertas, Felix Kahlhoefer, Tommaso Spadaro | Model-independent bounds on light pseudoscalars from rare B-meson decays | 10 pages, 3 figures; v2: matches version published in PLB; B-meson
spectra provided as ancillary file | Phys.Lett. B790 (2019) 537-544 | 10.1016/j.physletb.2019.01.064 | TTK-18-45 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | New light pseudoscalars, such as axion-like particles, appear in many
well-motivated extensions of the Standard Model and provide an exciting target
for present and future experiments. We study the experimental sensitivity for
such particles by revising the CHARM exclusion contour, updating bounds from
LHCb and presenting prospects for NA62 and SHiP. We first consider a simplified
model of a light pseudoscalar $A$ and then propose a model-independent approach
applicable to any spin-0 boson light enough to be produced in B-meson decays.
As illustration, we provide upper bounds on $\text{BR}(B \to K\,A) \times
\text{BR}(A \to \mu^+\mu^-)$ as a function of the boson lifetime and mass for
models that satisfy minimal flavour violation. Our results demonstrate the
important complementarity between different experiments resulting from their
different geometries.
| [
{
"created": "Fri, 26 Oct 2018 14:11:45 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Feb 2019 12:59:51 GMT",
"version": "v2"
}
] | 2019-02-20 | [
[
"Döbrich",
"Babette",
""
],
[
"Ertas",
"Fatih",
""
],
[
"Kahlhoefer",
"Felix",
""
],
[
"Spadaro",
"Tommaso",
""
]
] | New light pseudoscalars, such as axion-like particles, appear in many well-motivated extensions of the Standard Model and provide an exciting target for present and future experiments. We study the experimental sensitivity for such particles by revising the CHARM exclusion contour, updating bounds from LHCb and presenting prospects for NA62 and SHiP. We first consider a simplified model of a light pseudoscalar $A$ and then propose a model-independent approach applicable to any spin-0 boson light enough to be produced in B-meson decays. As illustration, we provide upper bounds on $\text{BR}(B \to K\,A) \times \text{BR}(A \to \mu^+\mu^-)$ as a function of the boson lifetime and mass for models that satisfy minimal flavour violation. Our results demonstrate the important complementarity between different experiments resulting from their different geometries. |
1007.4200 | Itay Yavin | Spencer Chang, Neal Weiner, and Itay Yavin | Magnetic Inelastic Dark Matter | 8 pages, 3 figs; v3: added discussion and figures to elucidate the
uncertainties associated with the dipole form-factors. Conclusions unchanged.
Published version | Phys.Rev.D82:125011,2010 | 10.1103/PhysRevD.82.125011 | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Iodine is distinguished from other elements used in dark matter direct
detection experiments both by its large mass as well as its large magnetic
moment. Inelastic dark matter utilizes the large mass of iodine to allay
tensions between the DAMA annual modulation signature and the null results from
other experiments. We explore models of inelastic dark matter that also take
advantage of the second distinct property of iodine, namely its large magnetic
moment. In such models the couplings are augmented by magnetic, rather than
merely electric, interactions. These models provide simple examples where the
DAMA signal is compatible with all existing limits. We consider dipole moments
for the WIMP, through conventional magnetism as well as "dark" magnetism,
including both magnetic-magnetic and magnetic-electric scattering. We find
XENON100 and CRESST should generically see a signal, although suppressed
compared with electric inelastic dark matter models, while KIMS should see a
modulated signal comparable to or larger than that of DAMA. In a large portion
of parameter space, de-excitation occurs promptly, producing a ~ 100 keV photon
inside large xenon experiments alongside the nuclear recoil. This effect could
be searched for, but if not properly considered may cause nuclear recoil events
to fail standard cuts.
| [
{
"created": "Fri, 23 Jul 2010 20:00:03 GMT",
"version": "v1"
},
{
"created": "Thu, 29 Jul 2010 18:25:20 GMT",
"version": "v2"
},
{
"created": "Thu, 16 Dec 2010 11:54:51 GMT",
"version": "v3"
}
] | 2010-12-23 | [
[
"Chang",
"Spencer",
""
],
[
"Weiner",
"Neal",
""
],
[
"Yavin",
"Itay",
""
]
] | Iodine is distinguished from other elements used in dark matter direct detection experiments both by its large mass as well as its large magnetic moment. Inelastic dark matter utilizes the large mass of iodine to allay tensions between the DAMA annual modulation signature and the null results from other experiments. We explore models of inelastic dark matter that also take advantage of the second distinct property of iodine, namely its large magnetic moment. In such models the couplings are augmented by magnetic, rather than merely electric, interactions. These models provide simple examples where the DAMA signal is compatible with all existing limits. We consider dipole moments for the WIMP, through conventional magnetism as well as "dark" magnetism, including both magnetic-magnetic and magnetic-electric scattering. We find XENON100 and CRESST should generically see a signal, although suppressed compared with electric inelastic dark matter models, while KIMS should see a modulated signal comparable to or larger than that of DAMA. In a large portion of parameter space, de-excitation occurs promptly, producing a ~ 100 keV photon inside large xenon experiments alongside the nuclear recoil. This effect could be searched for, but if not properly considered may cause nuclear recoil events to fail standard cuts. |
2206.06927 | Yuri B. Ivanov | Yu. B. Ivanov and A. A. Soldatov | On Ambiguity of Definition of Shear and Spin-Hall Contributions to
$\Lambda$ Polarization in Heavy-Ion Collisions | 3 pages, version accepted by JETP Letters, minor changes in text and
references | null | 10.1134/S0021364022601300 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | Recently proposed thermal-shear and spin-Hall contributions to the particle
polarization in heavy-ion collisions are discussed. Alternative definitions of
the thermal-shear contribution, i.e. those of Becattini-Buzzegoli-Palermo on
the one hand and Liu-Yin on the other, are very similar in the midrapidity
region while quite different at forward-backward rapidities, which are measured
in fixed-target experiments. It is shown that the thermal-shear contribution to
the global polarization with momentum averaging extended to all momenta is very
different within these alternative definitions. The spin-Hall contribution to
the global polarization, defined similarly to the Liu-Yin shear one, is
identically zero, if averaging runs over all momenta. Only application of
restrictive momentum acceptance and the boost (to $\Lambda$ rest frame)
correction result in nonzero global spin-Hall polarization. If the spin-Hall
contribution were defined similarly to Becattini-Buzzegoli-Palermo shear one,
the global spin-Hall polarization would be non-zero even without any acceptance
and the boost correction.
| [
{
"created": "Tue, 14 Jun 2022 15:48:24 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Jun 2022 13:44:45 GMT",
"version": "v2"
},
{
"created": "Tue, 28 Jun 2022 13:00:33 GMT",
"version": "v3"
}
] | 2022-08-10 | [
[
"Ivanov",
"Yu. B.",
""
],
[
"Soldatov",
"A. A.",
""
]
] | Recently proposed thermal-shear and spin-Hall contributions to the particle polarization in heavy-ion collisions are discussed. Alternative definitions of the thermal-shear contribution, i.e. those of Becattini-Buzzegoli-Palermo on the one hand and Liu-Yin on the other, are very similar in the midrapidity region while quite different at forward-backward rapidities, which are measured in fixed-target experiments. It is shown that the thermal-shear contribution to the global polarization with momentum averaging extended to all momenta is very different within these alternative definitions. The spin-Hall contribution to the global polarization, defined similarly to the Liu-Yin shear one, is identically zero, if averaging runs over all momenta. Only application of restrictive momentum acceptance and the boost (to $\Lambda$ rest frame) correction result in nonzero global spin-Hall polarization. If the spin-Hall contribution were defined similarly to Becattini-Buzzegoli-Palermo shear one, the global spin-Hall polarization would be non-zero even without any acceptance and the boost correction. |
2010.02954 | Jui-Lin Kuo | C\'eline B{\oe}hm, Xiaoyong Chu, Jui-Lin Kuo, Josef Pradler | Scalar Dark Matter Candidates -- Revisited | 22 pages, 9 figures; to match the published version | Phys. Rev. D 103, 075005 (2021) | 10.1103/PhysRevD.103.075005 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the possibility of light scalar dark matter, in the MeV to GeV
mass bracket and coupled to electrons through fermion or vector mediators, in
light of significant experimental and observational advances that probe new
physics below the GeV-scale. We establish new limits from electron colliders
and fixed-target beams, and derive the strength of loop-induced processes that
are probed by precision physics, among other laboratory probes. In addition, we
compute the cooling bound from SN1987A, consider self-scattering, structure
formation, and cosmological constraints as well as the limits from dark
matter-electron scattering in direct detection experiments. We then show that
the combination of constraints largely excludes the possibility that the
galactic annihilation of these particles may explain the long-standing INTEGRAL
excess of 511 keV photons as observed in the galactic bulge. As caveat to these
conclusions we identify the resonant annihilation regime where the vector
mediator goes nearly on-shell.
| [
{
"created": "Tue, 6 Oct 2020 18:07:48 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Mar 2021 10:22:15 GMT",
"version": "v2"
}
] | 2021-04-14 | [
[
"Bœhm",
"Céline",
""
],
[
"Chu",
"Xiaoyong",
""
],
[
"Kuo",
"Jui-Lin",
""
],
[
"Pradler",
"Josef",
""
]
] | We revisit the possibility of light scalar dark matter, in the MeV to GeV mass bracket and coupled to electrons through fermion or vector mediators, in light of significant experimental and observational advances that probe new physics below the GeV-scale. We establish new limits from electron colliders and fixed-target beams, and derive the strength of loop-induced processes that are probed by precision physics, among other laboratory probes. In addition, we compute the cooling bound from SN1987A, consider self-scattering, structure formation, and cosmological constraints as well as the limits from dark matter-electron scattering in direct detection experiments. We then show that the combination of constraints largely excludes the possibility that the galactic annihilation of these particles may explain the long-standing INTEGRAL excess of 511 keV photons as observed in the galactic bulge. As caveat to these conclusions we identify the resonant annihilation regime where the vector mediator goes nearly on-shell. |
hep-ph/0105172 | Hai Lin | Hai Lin | Analytic Derivation of the Quark Distribution Functions Near x=1 by
Statistical Methods | 8 pages, LaTex | null | null | null | hep-ph | null | In this paper, we made a statistical approach on the thermodynamic structure
of the nucleon and its quark distributions. We assume that the nucleon is a
thermodynamic system of quarks and gluons. After we derived the quark density
of states from the Dirac Equation, we calculated each quark's chemical
potential, associating it with the quark's spin distribution. By using the sum
rule of the longitudinal momentum, we obtain a function showing the relation
between the temperature, radius and mass of the nucleon. The nucleon's radius
is determined by the total energy minimal principle, and thus the temperature
is also known. Finally, we deduced the quark distribution functions near x=1,
and the results are in agreement with the experimental data.
| [
{
"created": "Thu, 17 May 2001 20:15:30 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lin",
"Hai",
""
]
] | In this paper, we made a statistical approach on the thermodynamic structure of the nucleon and its quark distributions. We assume that the nucleon is a thermodynamic system of quarks and gluons. After we derived the quark density of states from the Dirac Equation, we calculated each quark's chemical potential, associating it with the quark's spin distribution. By using the sum rule of the longitudinal momentum, we obtain a function showing the relation between the temperature, radius and mass of the nucleon. The nucleon's radius is determined by the total energy minimal principle, and thus the temperature is also known. Finally, we deduced the quark distribution functions near x=1, and the results are in agreement with the experimental data. |
hep-ph/0309286 | Wieslaw Sobk\'ow | S. Ciechanowicz (1), M. Misiaszek (2), W. Sobkow (1) (1 University of
Wroclaw, Poland) (2 Jagiellonian University, Poland) | Scattering of neutrinos on a polarized electron target as a test for new
physics beyond the Standard Model | 11 pages, 3 eps figures, revtex, submitted to publication | Phys.Rev.D71:093006,2005 | 10.1103/PhysRevD.71.093006 | null | hep-ph | null | In this paper, we analyze the scattering of the neutrino beam on the
polarized electron target, and predict the effects of two theoretically
possible scenarios beyond the Standard Model. In both scenarios, Dirac
neutrinos are assumed to be massive.
First, we consider how the existence of CP violation phase between the
complex vector V and axial A couplings of the Left-handed neutrinos affects the
azimuthal dependence of the differential cross section. The future superbeam
and neutrino factory experiments will provide the unique opportunity for the
leptonic CP violation studies, if the large magnetized sampling calorimeters
with good event reconstruction capabilities are build.
Next, we take into account a scenario with the participation of the exotic
scalar S coupling of the Right-handed neutrinos in addition to the standard
vector V and axial A couplings of the Left-handed neutrinos. The main goal is
to show how the presence of the R-handed neutrinos, in the above process
changes the spectrum of recoil electrons in relation to the expected Standard
Model prediction, using the current limits on the non-standard couplings. The
interference terms between the standard and exotic couplings in the
differential cross section depend on the angle $\alpha$ between the transverse
incoming neutrino polarization and the transverse electron polarization of the
target, and do not vanish in the limit of massless neutrino. The detection of
the dependence on this angle in the energy spectrum of recoil electrons would
be a signature of the presence of the R-handed neutrinos in the
neutrino-electron scattering. To make this test feasible, the polarized
artificial neutrino source needs to be identified.
| [
{
"created": "Thu, 25 Sep 2003 12:38:35 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Jan 2005 16:14:01 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Ciechanowicz",
"S.",
""
],
[
"Misiaszek",
"M.",
""
],
[
"Sobkow",
"W.",
""
]
] | In this paper, we analyze the scattering of the neutrino beam on the polarized electron target, and predict the effects of two theoretically possible scenarios beyond the Standard Model. In both scenarios, Dirac neutrinos are assumed to be massive. First, we consider how the existence of CP violation phase between the complex vector V and axial A couplings of the Left-handed neutrinos affects the azimuthal dependence of the differential cross section. The future superbeam and neutrino factory experiments will provide the unique opportunity for the leptonic CP violation studies, if the large magnetized sampling calorimeters with good event reconstruction capabilities are build. Next, we take into account a scenario with the participation of the exotic scalar S coupling of the Right-handed neutrinos in addition to the standard vector V and axial A couplings of the Left-handed neutrinos. The main goal is to show how the presence of the R-handed neutrinos, in the above process changes the spectrum of recoil electrons in relation to the expected Standard Model prediction, using the current limits on the non-standard couplings. The interference terms between the standard and exotic couplings in the differential cross section depend on the angle $\alpha$ between the transverse incoming neutrino polarization and the transverse electron polarization of the target, and do not vanish in the limit of massless neutrino. The detection of the dependence on this angle in the energy spectrum of recoil electrons would be a signature of the presence of the R-handed neutrinos in the neutrino-electron scattering. To make this test feasible, the polarized artificial neutrino source needs to be identified. |
2210.03795 | Gong-Ming Yu | Gongming Yu, Yanbing Cai, Quangui Gao, and Qiang Hu | Production of $\chi_{c}$ and $\eta_{c}$ production in ultra-peripheral
collisions with two-photon processes | 6 pages, 2 figures. arXiv admin note: text overlap with
arXiv:2209.11439 | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | We calculate the production of $\chi_{c}$ and $\eta_{c}$ by the semi-coherent
and coherent two-photon interaction in ultra-peripheral heavy ion collisions at
Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC)
energies. The differential cross section of transverse momentum distribution
and rapidity distribution for $AB\stackrel{\gamma\gamma}{\longrightarrow}AHB$
(H=$\chi_{c}$ and $\eta_{c}$), are estimated by using the equivalent photon
approximation in ultra-peripheral nucleus-nucleus collisions. The numerical
results demonstrate that the experimental study of $\chi_{c}$ and $\eta_{c}$ in
ultra-peripheral nucleus-nucleus collisions is feasible at RHIC and LHC
energies.
| [
{
"created": "Fri, 7 Oct 2022 19:55:30 GMT",
"version": "v1"
}
] | 2022-10-11 | [
[
"Yu",
"Gongming",
""
],
[
"Cai",
"Yanbing",
""
],
[
"Gao",
"Quangui",
""
],
[
"Hu",
"Qiang",
""
]
] | We calculate the production of $\chi_{c}$ and $\eta_{c}$ by the semi-coherent and coherent two-photon interaction in ultra-peripheral heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies. The differential cross section of transverse momentum distribution and rapidity distribution for $AB\stackrel{\gamma\gamma}{\longrightarrow}AHB$ (H=$\chi_{c}$ and $\eta_{c}$), are estimated by using the equivalent photon approximation in ultra-peripheral nucleus-nucleus collisions. The numerical results demonstrate that the experimental study of $\chi_{c}$ and $\eta_{c}$ in ultra-peripheral nucleus-nucleus collisions is feasible at RHIC and LHC energies. |
1505.04738 | Hendrik van Hees | Carsten Greiner, Christian Wesp, Hendrik van Hees, Alex Meistrenko | Monte-Carlo approach to particle-field interactions and the kinetics of
the chiral phase transition | 7 pages, 7 figures, contribution to the proceedings of the 31st
Winter Workshop on Nuclear Dynamics 2015 | null | 10.1088/1742-6596/636/1/012007 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The kinetics of the chiral phase transition is studied within a linear
quark-meson-$\sigma$ model, using a Monte-Carlo approach to semiclassical
particle-field dynamics. The meson fields are described on the mean-field level
and quarks and antiquarks as ensembles of test particles. Collisions between
quarks and antiquarks as well as the $q\overline{q}$ annihilation to $\sigma$
mesons and the decay of $\sigma$ mesons is treated, using the corresponding
transition-matrix elements from the underlying quantum field theory, obeying
strictly the rule of detailed balance and energy-momentum conservation. The
approach allows to study fluctuations without making ad hoc assumptions
concerning the statistical nature of the random process as necessary in
Langevin-Fokker-Planck frameworks.
| [
{
"created": "Mon, 18 May 2015 17:58:24 GMT",
"version": "v1"
}
] | 2015-09-30 | [
[
"Greiner",
"Carsten",
""
],
[
"Wesp",
"Christian",
""
],
[
"van Hees",
"Hendrik",
""
],
[
"Meistrenko",
"Alex",
""
]
] | The kinetics of the chiral phase transition is studied within a linear quark-meson-$\sigma$ model, using a Monte-Carlo approach to semiclassical particle-field dynamics. The meson fields are described on the mean-field level and quarks and antiquarks as ensembles of test particles. Collisions between quarks and antiquarks as well as the $q\overline{q}$ annihilation to $\sigma$ mesons and the decay of $\sigma$ mesons is treated, using the corresponding transition-matrix elements from the underlying quantum field theory, obeying strictly the rule of detailed balance and energy-momentum conservation. The approach allows to study fluctuations without making ad hoc assumptions concerning the statistical nature of the random process as necessary in Langevin-Fokker-Planck frameworks. |
1212.1066 | Alexander J. Stuart | Iain K. Cooper, Stephen F. King, Alexander J. Stuart | A Golden A_5 Model of Leptons with a Minimal NLO Correction | 39 pages, 6 figures, version published in Nuclear Physics B | null | 10.1016/j.nuclphysb.2013.07.027 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a new A_5 model of leptons which corrects the LO predictions of
Golden Ratio mixing via a minimal NLO Majorana mass correction which completely
breaks the original Klein symmetry of the neutrino mass matrix. The minimal
nature of the NLO correction leads to a restricted and correlated range of the
mixing angles allowing agreement within the one sigma range of recent global
fits following the reactor angle measurement by Daya Bay and RENO. The minimal
NLO correction also preserves the LO inverse neutrino mass sum rule leading to
a neutrino mass spectrum that extends into the quasi-degenerate region allowing
the model to be accessible to the current and future neutrinoless double beta
decay experiments.
| [
{
"created": "Wed, 5 Dec 2012 15:50:14 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Aug 2013 10:07:00 GMT",
"version": "v2"
}
] | 2015-06-12 | [
[
"Cooper",
"Iain K.",
""
],
[
"King",
"Stephen F.",
""
],
[
"Stuart",
"Alexander J.",
""
]
] | We propose a new A_5 model of leptons which corrects the LO predictions of Golden Ratio mixing via a minimal NLO Majorana mass correction which completely breaks the original Klein symmetry of the neutrino mass matrix. The minimal nature of the NLO correction leads to a restricted and correlated range of the mixing angles allowing agreement within the one sigma range of recent global fits following the reactor angle measurement by Daya Bay and RENO. The minimal NLO correction also preserves the LO inverse neutrino mass sum rule leading to a neutrino mass spectrum that extends into the quasi-degenerate region allowing the model to be accessible to the current and future neutrinoless double beta decay experiments. |
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