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0710.3060
Krzysztof Kutak
Jochen Bartels, Krzysztof Kutak
A momentum Space Analysis of the Triple Pomeron Vertex in pQCD
Minor misprints corrected. To be published in EPJC
Eur.Phys.J.C53:533-548,2008
10.1140/epjc/s10052-007-0501-6
DESY-07-185
hep-ph hep-th
null
We study properties of the momentum space Triple Pomeron Vertex in perturbative QCD. Particular attention is given to the collinear limit where transverse momenta on one side of the vertex are much larger than on the other side. We also comment on the kernels in nonlinear evolution equations.
[ { "created": "Tue, 16 Oct 2007 13:41:40 GMT", "version": "v1" }, { "created": "Tue, 4 Dec 2007 12:56:18 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bartels", "Jochen", "" ], [ "Kutak", "Krzysztof", "" ] ]
We study properties of the momentum space Triple Pomeron Vertex in perturbative QCD. Particular attention is given to the collinear limit where transverse momenta on one side of the vertex are much larger than on the other side. We also comment on the kernels in nonlinear evolution equations.
0901.2559
Michael Lublinsky
Tolga Altinoluk, Alex Kovner, Michael Lublinsky, Javier Peressutti
QCD Reggeon Field Theory for every day: Pomeron loops included
35 pages, 5 figures
JHEP 0903:109,2009
10.1088/1126-6708/2009/03/109
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive the evolution equation for hadronic scattering amplitude at high energy. Our derivation includes the nonlinear effects of finite partonic density in the hadronic wave function as well as the effect of multiple scatterings for scattering on dense hadronic target. It thus includes Pomeron loops. It is based on the evolution of the hadronic wave function derived in \cite{foam}. The kernel of the evolution equation defines the second quantized Hamiltonian of the QCD Reggeon Field Theory, $H_{RFT}$ beyond the limits considered so far. The two previously known limits of the evolution: dilute target (JIMWLK limit) and dilute projectile (KLWMIJ limit) are recovered directly from our final result. The Hamiltonian $H_{RFT}$ is applicable for the evolution of scattering amplitude for arbitrarily dense hadronic projectiles/targets - from "dipole-dipole" to "nucleus-nucleus" scattering processes.
[ { "created": "Fri, 16 Jan 2009 20:20:14 GMT", "version": "v1" } ]
2009-04-02
[ [ "Altinoluk", "Tolga", "" ], [ "Kovner", "Alex", "" ], [ "Lublinsky", "Michael", "" ], [ "Peressutti", "Javier", "" ] ]
We derive the evolution equation for hadronic scattering amplitude at high energy. Our derivation includes the nonlinear effects of finite partonic density in the hadronic wave function as well as the effect of multiple scatterings for scattering on dense hadronic target. It thus includes Pomeron loops. It is based on the evolution of the hadronic wave function derived in \cite{foam}. The kernel of the evolution equation defines the second quantized Hamiltonian of the QCD Reggeon Field Theory, $H_{RFT}$ beyond the limits considered so far. The two previously known limits of the evolution: dilute target (JIMWLK limit) and dilute projectile (KLWMIJ limit) are recovered directly from our final result. The Hamiltonian $H_{RFT}$ is applicable for the evolution of scattering amplitude for arbitrarily dense hadronic projectiles/targets - from "dipole-dipole" to "nucleus-nucleus" scattering processes.
0907.3159
Jure Zupan
Joachim Kopp, Viviana Niro, Thomas Schwetz, Jure Zupan
DAMA/LIBRA and leptonically interacting Dark Matter
33 pages, 11 figures
Phys.Rev.D80:083502,2009
10.1103/PhysRevD.80.083502
CERN-PH-TH/2009-116
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the hypothesis that Dark Matter (DM) has tree-level interactions only with leptons. Such a framework, where DM recoils against electrons bound in atoms, has been proposed as an explanation for the annually modulated scintillation signal in DAMA/LIBRA versus the absence of a signal for nuclear recoils in experiments like CDMS or XENON10. However, even in such a leptophilic DM scenario there are loop induced DM-hadron interactions, where the photons emitted from virtual leptons couple to the charge of a nucleus. Using a general effective field theory approach we show that, if such an interaction is induced at one or two-loop level, then DM-nucleus scattering dominates over DM-electron scattering. This is because the latter is suppressed by the bound state wave function. One obtains a situation similar to standard DM-nucleus scattering analyses with considerable tension between the results of DAMA and CDMS/XENON10. This conclusion does not apply in the case of pseudoscalar or axial vector coupling between DM and leptons, where the loop diagrams vanish. In this case the explanation of the DAMA signal in terms of DM-electron scattering is strongly disfavored by the spectral shape of the signal. Furthermore, if DM can annihilate into neutrinos or tau leptons, the required cross sections are excluded by many orders of magnitude using the Super-Kamiokande bound on neutrinos from DM annihilations in the Sun.
[ { "created": "Mon, 20 Jul 2009 11:21:57 GMT", "version": "v1" }, { "created": "Fri, 2 Oct 2009 19:42:43 GMT", "version": "v2" } ]
2010-01-15
[ [ "Kopp", "Joachim", "" ], [ "Niro", "Viviana", "" ], [ "Schwetz", "Thomas", "" ], [ "Zupan", "Jure", "" ] ]
We consider the hypothesis that Dark Matter (DM) has tree-level interactions only with leptons. Such a framework, where DM recoils against electrons bound in atoms, has been proposed as an explanation for the annually modulated scintillation signal in DAMA/LIBRA versus the absence of a signal for nuclear recoils in experiments like CDMS or XENON10. However, even in such a leptophilic DM scenario there are loop induced DM-hadron interactions, where the photons emitted from virtual leptons couple to the charge of a nucleus. Using a general effective field theory approach we show that, if such an interaction is induced at one or two-loop level, then DM-nucleus scattering dominates over DM-electron scattering. This is because the latter is suppressed by the bound state wave function. One obtains a situation similar to standard DM-nucleus scattering analyses with considerable tension between the results of DAMA and CDMS/XENON10. This conclusion does not apply in the case of pseudoscalar or axial vector coupling between DM and leptons, where the loop diagrams vanish. In this case the explanation of the DAMA signal in terms of DM-electron scattering is strongly disfavored by the spectral shape of the signal. Furthermore, if DM can annihilate into neutrinos or tau leptons, the required cross sections are excluded by many orders of magnitude using the Super-Kamiokande bound on neutrinos from DM annihilations in the Sun.
1312.1966
Martin Spinrath
Ivan Girardi, Aurora Meroni, S. T. Petcov, Martin Spinrath
Generalised Geometrical CP Violation in a $T^{\prime}$ Lepton Flavour Model
39 pages, 5 figures, 9 tables; Results unchanged; two typos in eqs. (3.70) and (3.71) corrected
JHEP02 (2014) 050
10.1007/JHEP02(2014)050
SISSA 56/2013/FISI, RM3-TH/13-10, TTP13-04
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyse the interplay of generalised CP transformations and the non-Abelian discrete group $T^{\prime}$ and use the semi-direct product $G_f= T^{\prime}\rtimes H_{\text{CP}}$, as family symmetry acting in the lepton sector. The family symmetry is shown to be spontaneously broken in a geometrical manner. In the resulting flavour model, naturally small Majorana neutrino masses for the light active neutrinos are obtained through the type I see-saw mechanism. The known masses of the charged leptons, lepton mixing angles and the two neutrino mass squared differences are reproduced by the model with a good accuracy. The model allows for two neutrino mass spectra with normal ordering (NO) and one with inverted ordering (IO). For each of the three spectra the absolute scale of neutrino masses is predicted with relatively small uncertainty. The value of the Dirac CP violation (CPV) phase $\delta$ in the lepton mixing matrix is predicted to be $\delta \cong \pi/2~{\rm or}~ 3\pi/2$. Thus, the CP violating effects in neutrino oscillations are predicted to be maximal (given the values of the neutrino mixing angles) and experimentally observable. We present also predictions for the sum of the neutrino masses, for the Majorana CPV phases and for the effective Majorana mass in neutrinoless double beta decay. The predictions of the model can be tested in a variety of ongoing and future planned neutrino experiments.
[ { "created": "Fri, 6 Dec 2013 19:14:31 GMT", "version": "v1" }, { "created": "Thu, 12 Dec 2013 14:28:44 GMT", "version": "v2" }, { "created": "Wed, 5 Mar 2014 10:04:20 GMT", "version": "v3" }, { "created": "Mon, 19 May 2014 08:27:20 GMT", "version": "v4" } ]
2014-05-20
[ [ "Girardi", "Ivan", "" ], [ "Meroni", "Aurora", "" ], [ "Petcov", "S. T.", "" ], [ "Spinrath", "Martin", "" ] ]
We analyse the interplay of generalised CP transformations and the non-Abelian discrete group $T^{\prime}$ and use the semi-direct product $G_f= T^{\prime}\rtimes H_{\text{CP}}$, as family symmetry acting in the lepton sector. The family symmetry is shown to be spontaneously broken in a geometrical manner. In the resulting flavour model, naturally small Majorana neutrino masses for the light active neutrinos are obtained through the type I see-saw mechanism. The known masses of the charged leptons, lepton mixing angles and the two neutrino mass squared differences are reproduced by the model with a good accuracy. The model allows for two neutrino mass spectra with normal ordering (NO) and one with inverted ordering (IO). For each of the three spectra the absolute scale of neutrino masses is predicted with relatively small uncertainty. The value of the Dirac CP violation (CPV) phase $\delta$ in the lepton mixing matrix is predicted to be $\delta \cong \pi/2~{\rm or}~ 3\pi/2$. Thus, the CP violating effects in neutrino oscillations are predicted to be maximal (given the values of the neutrino mixing angles) and experimentally observable. We present also predictions for the sum of the neutrino masses, for the Majorana CPV phases and for the effective Majorana mass in neutrinoless double beta decay. The predictions of the model can be tested in a variety of ongoing and future planned neutrino experiments.
hep-ph/0011255
Hubert Spiesberger
H.Spiesberger, M.Spira and P.M.Zerwas
The Standard Model: Physical Basis and Scattering Experiments
65 pages, 25 figures, LaTeX, to be published in "Scattering", P. Sabatier (ed.), Academic Press, London (2000)
null
null
DESY T-00-01, MZ-TH/00-53, PSI-PR-00-17
hep-ph hep-ex hep-th
null
We present an introduction into the basic concepts of the Standard Model, i.e. the gauge theories of the forces and the Higgs mechanism for generating masses. The Glashow-Salam-Weinberg theory of the electroweak interactions will be described in detail. The key experiments are reviewed, including the precision tests at high energies. Finally, the limitations and possible physics areas beyond the Standard Model are discussed.
[ { "created": "Tue, 21 Nov 2000 13:32:19 GMT", "version": "v1" } ]
2007-05-23
[ [ "Spiesberger", "H.", "" ], [ "Spira", "M.", "" ], [ "Zerwas", "P. M.", "" ] ]
We present an introduction into the basic concepts of the Standard Model, i.e. the gauge theories of the forces and the Higgs mechanism for generating masses. The Glashow-Salam-Weinberg theory of the electroweak interactions will be described in detail. The key experiments are reviewed, including the precision tests at high energies. Finally, the limitations and possible physics areas beyond the Standard Model are discussed.
1708.04534
Tong Li
Tong Li
Revisiting simplified dark matter models in terms of AMS-02 and Fermi-LAT
20 pages, 8 figures, 2 tables. arXiv admin note: text overlap with arXiv:1612.09501
null
10.1007/JHEP01(2018)151
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform an analysis of the simplified dark matter models in the light of cosmic ray observables by AMS-02 and Fermi-LAT. We assume fermion, scalar or vector dark matter particle with a leptophobic spin-0 mediator that couples only to Standard Model quarks and dark matter via scalar and/or pseudo-scalar bilinear. The propagation and injection parameters of cosmic rays are determined by the observed fluxes of nuclei from AMS-02. We find that the AMS-02 observations are consistent with the dark matter framework within the uncertainties. The AMS-02 antiproton data prefer 30 (50) GeV - 5 TeV dark matter mass and require an effective annihilation cross section in the region of 4x10^{-27} (7x10^{-27}) - 4x10^{-24} cm^3/s for the simplified fermion (scalar and vector) dark matter models. The cross sections below 2x10^{-26} cm^3/s can evade the constraint from Fermi-LAT dwarf galaxies for about 100 GeV dark matter mass.
[ { "created": "Sat, 12 Aug 2017 13:02:04 GMT", "version": "v1" } ]
2018-03-14
[ [ "Li", "Tong", "" ] ]
We perform an analysis of the simplified dark matter models in the light of cosmic ray observables by AMS-02 and Fermi-LAT. We assume fermion, scalar or vector dark matter particle with a leptophobic spin-0 mediator that couples only to Standard Model quarks and dark matter via scalar and/or pseudo-scalar bilinear. The propagation and injection parameters of cosmic rays are determined by the observed fluxes of nuclei from AMS-02. We find that the AMS-02 observations are consistent with the dark matter framework within the uncertainties. The AMS-02 antiproton data prefer 30 (50) GeV - 5 TeV dark matter mass and require an effective annihilation cross section in the region of 4x10^{-27} (7x10^{-27}) - 4x10^{-24} cm^3/s for the simplified fermion (scalar and vector) dark matter models. The cross sections below 2x10^{-26} cm^3/s can evade the constraint from Fermi-LAT dwarf galaxies for about 100 GeV dark matter mass.
1201.6127
Kiyoshi Kato
K. Kato, E. de Doncker, N. Hamaguchi, T. Ishikawa, T. Koike, Y. Kurihara, Y. Shimizu and F.Yuasa
Numerical approach to multi-loop integrals
7 pages; The XXth International Workshop High Energy Physics and Quantum Field Theory, September 24-October 1, 2011, Sochi Russia
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For the calculation of multi-loop Feynman integrals, a novel numerical method, the Direct Computation Method (DCM) is developed. It is a combination of a numerical integration and a series extrapolation. In principle, DCM can handle diagrams of arbitrary internal masses and external momenta, and can calculate integrals with general numerator function. As an example of the performance of DCM, a numerical computation of two-loop box diagrams is presented. Further discussion is given on the choice of control parameters in DCM. This method will be an indispensable tool for the higher order radiative correction when it is tested for a wider class of physical parameters and the separation of divergence is done automatically.
[ { "created": "Mon, 30 Jan 2012 08:24:18 GMT", "version": "v1" } ]
2012-01-31
[ [ "Kato", "K.", "" ], [ "de Doncker", "E.", "" ], [ "Hamaguchi", "N.", "" ], [ "Ishikawa", "T.", "" ], [ "Koike", "T.", "" ], [ "Kurihara", "Y.", "" ], [ "Shimizu", "Y.", "" ], [ "Yuasa", "F.", "" ] ]
For the calculation of multi-loop Feynman integrals, a novel numerical method, the Direct Computation Method (DCM) is developed. It is a combination of a numerical integration and a series extrapolation. In principle, DCM can handle diagrams of arbitrary internal masses and external momenta, and can calculate integrals with general numerator function. As an example of the performance of DCM, a numerical computation of two-loop box diagrams is presented. Further discussion is given on the choice of control parameters in DCM. This method will be an indispensable tool for the higher order radiative correction when it is tested for a wider class of physical parameters and the separation of divergence is done automatically.
1201.5389
Vojt\v{e}ch Krej\v{c}i\v{r}\'ik
Thomas D. Cohen, Vojt\v{e}ch Krej\v{c}i\v{r}\'ik
Model-independent form factor relations at large $N_c$
null
Phys. Rev. C 85, 035205 (2012)
10.1103/PhysRevC.85.035205
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper a model-independent relation which holds for the long distance part of the Fourier transform of the electromagnetic form factors of the nucleon in the large $N_c$ and chiral limits is demonstrated. This relation was previously conjectured based on the fact that it emerged in {\it all} semiclassical chiral models independent of the details of the model. Here we show that the result is, in fact, model independent by deriving it directly in large $N_c$ chiral perturbation theory which is known to capture the long distance behavior of the form factors. The relation is valid when the large $N_c$ limit is formally taken before the chiral limit. A new relation is derived for the case where the chiral limit is taken prior to the large $N_c$ limit.
[ { "created": "Wed, 25 Jan 2012 21:07:44 GMT", "version": "v1" }, { "created": "Tue, 10 Apr 2012 19:18:34 GMT", "version": "v2" } ]
2012-04-11
[ [ "Cohen", "Thomas D.", "" ], [ "Krejčiřík", "Vojtěch", "" ] ]
In this paper a model-independent relation which holds for the long distance part of the Fourier transform of the electromagnetic form factors of the nucleon in the large $N_c$ and chiral limits is demonstrated. This relation was previously conjectured based on the fact that it emerged in {\it all} semiclassical chiral models independent of the details of the model. Here we show that the result is, in fact, model independent by deriving it directly in large $N_c$ chiral perturbation theory which is known to capture the long distance behavior of the form factors. The relation is valid when the large $N_c$ limit is formally taken before the chiral limit. A new relation is derived for the case where the chiral limit is taken prior to the large $N_c$ limit.
1312.2504
Shaaban Khalil
M. Hemeda, S. Khalil, S. Moretti
Light Chargino Effects onto H -> gamma gamma in the MSSM
5 pages, 5 Figures
null
10.1103/PhysRevD.89.011701
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyse the implications of light charginos on the Higgs boson signal strength via gluon-gluon fusion and di-photon decay in the Minimal Supersymmetric Standard Model (MSSM) at the Large Hadron Collider (LHC). We show that enhancements are possible with a rate up to 25%. We also prove that they are possible for a high scale constrained version of the MSSM with non-universal Higgs and gaugino masses. In contrast, effects due to light charged Higgs bosons, that we also have investigated, are generically negligible in the \gamma\gamma decay, though they may affect the b \bar b rate, hence the total width.
[ { "created": "Mon, 9 Dec 2013 16:35:44 GMT", "version": "v1" } ]
2015-06-18
[ [ "Hemeda", "M.", "" ], [ "Khalil", "S.", "" ], [ "Moretti", "S.", "" ] ]
We analyse the implications of light charginos on the Higgs boson signal strength via gluon-gluon fusion and di-photon decay in the Minimal Supersymmetric Standard Model (MSSM) at the Large Hadron Collider (LHC). We show that enhancements are possible with a rate up to 25%. We also prove that they are possible for a high scale constrained version of the MSSM with non-universal Higgs and gaugino masses. In contrast, effects due to light charged Higgs bosons, that we also have investigated, are generically negligible in the \gamma\gamma decay, though they may affect the b \bar b rate, hence the total width.
0909.4477
Johan Bijnens
Johan Bijnens and Ilaria Jemos (Lund)
Determination of Low Energy Constants and testing Chiral Perturbation Theory at order $p^6$ (NNLO)
9 pages
PoS CD09:087,2009
null
LU TP 09-24
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the results of a search for relations between observables that are independent of the Chiral Perturbation Theory (ChPT) Next-to-Next-to-Leading Order (NNLO) Low-Energy Constants (LECs). We have found some relations between observables in $\pi\pi$, $\pi K$ scattering and $K_{l4}$ decay which have been evaluated numerically using fit 10 in \cite{Amoros:2001cp} for the NLO LECs. We also show some preliminary results for a new global fit of the NLO LECs
[ { "created": "Thu, 24 Sep 2009 15:22:19 GMT", "version": "v1" } ]
2014-11-20
[ [ "Bijnens", "Johan", "", "Lund" ], [ "Jemos", "Ilaria", "", "Lund" ] ]
We present the results of a search for relations between observables that are independent of the Chiral Perturbation Theory (ChPT) Next-to-Next-to-Leading Order (NNLO) Low-Energy Constants (LECs). We have found some relations between observables in $\pi\pi$, $\pi K$ scattering and $K_{l4}$ decay which have been evaluated numerically using fit 10 in \cite{Amoros:2001cp} for the NLO LECs. We also show some preliminary results for a new global fit of the NLO LECs
0904.1782
Gui-Jun Ding
Gui-Jun Ding
Possible Molecular States of $D^{*}_s\bar{D}^{*}_s$ System and Y(4140)
13 pages,2 figures
Eur.Phys.J.C64:297-308,2009
10.1140/epjc/s10052-009-1146-4
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The interpretation of Y(4140) as a $D^{*}_s\bar{D}^{*}_s$ molecule is studied dynamically in the one boson exchange approach, where $\sigma$, $\eta$ and $\phi$ exchange are included. Ten allowed $D^{*}_s\bar{D}^{*}_s$ states with low spin parity are considered, we find that the $J^{PC}=0^{++}$, $1^{+-}$, $0^{-+}$, $2^{++}$ and $1^{--}$ $D^{*}_s\bar{D}^{*}_s$ configurations are most tightly bound. We suggest the most favorable quantum numbers are $J^{PC}=0^{++}$ for Y(4140) as a $D^{*}_s\bar{D}^{*}_s$ molecule, however, $J^{PC}=0^{-+}$ and $2^{++}$ can not be excluded. We propose to search for the $1^{+-}$ and $1^{--}$ partners in the $J/\psi\eta$ and $J/\psi\eta'$ final states, which is an important test of the molecular hypothesis of Y(4140) and the reasonability of our model. The $0^{++}$ $B^{*}_s\bar{B}^{*}_s$ molecule is deeply bound, experimental search in the $\Upsilon(1S)\phi$ channel at Tevatron and LHC is suggested.
[ { "created": "Sat, 11 Apr 2009 07:25:36 GMT", "version": "v1" }, { "created": "Sat, 12 Sep 2009 13:27:16 GMT", "version": "v2" } ]
2009-11-05
[ [ "Ding", "Gui-Jun", "" ] ]
The interpretation of Y(4140) as a $D^{*}_s\bar{D}^{*}_s$ molecule is studied dynamically in the one boson exchange approach, where $\sigma$, $\eta$ and $\phi$ exchange are included. Ten allowed $D^{*}_s\bar{D}^{*}_s$ states with low spin parity are considered, we find that the $J^{PC}=0^{++}$, $1^{+-}$, $0^{-+}$, $2^{++}$ and $1^{--}$ $D^{*}_s\bar{D}^{*}_s$ configurations are most tightly bound. We suggest the most favorable quantum numbers are $J^{PC}=0^{++}$ for Y(4140) as a $D^{*}_s\bar{D}^{*}_s$ molecule, however, $J^{PC}=0^{-+}$ and $2^{++}$ can not be excluded. We propose to search for the $1^{+-}$ and $1^{--}$ partners in the $J/\psi\eta$ and $J/\psi\eta'$ final states, which is an important test of the molecular hypothesis of Y(4140) and the reasonability of our model. The $0^{++}$ $B^{*}_s\bar{B}^{*}_s$ molecule is deeply bound, experimental search in the $\Upsilon(1S)\phi$ channel at Tevatron and LHC is suggested.
0711.1611
Jiri Hejbal
Jiri Hejbal
The alternative approach to QCD analysis of the structure function F2gamma
Talk given at PHOTON 2007, Paris, France, July 2007, 4 pages, 4 figures
Nucl.Phys.Proc.Suppl.184:39-42,2008
10.1016/j.nuclphysbps.2008.09.132
null
hep-ph
null
The alternative approach to QCD analysis of the structure function F2gamma is presented. It differs from the conventional one by the presence of the terms, which in conventional approach appear in higher orders. The numerical results show that this difference is nonnegligible and may play an important role in the analysis on photon data of the future experiments.
[ { "created": "Mon, 12 Nov 2007 16:09:51 GMT", "version": "v1" } ]
2008-12-18
[ [ "Hejbal", "Jiri", "" ] ]
The alternative approach to QCD analysis of the structure function F2gamma is presented. It differs from the conventional one by the presence of the terms, which in conventional approach appear in higher orders. The numerical results show that this difference is nonnegligible and may play an important role in the analysis on photon data of the future experiments.
hep-ph/9308319
Sourendu Gupta
Sourendu Gupta
Electromagnetic Signals and Backgrounds in Heavy-Ion Collisions:
9 pages (incl figures), preprint HLRZ 53/93
Nucl.Phys.A566:69c-76c,1994
10.1016/0375-9474(94)90610-6
null
hep-ph hep-lat nucl-th
null
Aspects of the dilepton spectrum in heavy-ion collisions are discussed, with special emphasis on using lattice computations to guide the phenomenology of finite temperature hadronic matter. The background rates for continuum dileptons expected in forthcoming experiments are summarised. Properly augmented by data from ongoing measurements at HERA, these rates will serve as a calibrating background for QGP searches. Recent results on the temperature dependence of the hadronic spectrum obtained in lattice computations below the deconfinement transition are summarised. Light vector meson masses are strongly temperature dependent. Accurate measurements of a resolved $\rho$-peak in dimuon spectra in present experiments are thus of fundamental importance. [file-length=200k characters; instructions for processing given; some Latex versions give error messages: ignore them completely]
[ { "created": "Mon, 23 Aug 1993 16:22:34 GMT", "version": "v1" } ]
2010-11-01
[ [ "Gupta", "Sourendu", "" ] ]
Aspects of the dilepton spectrum in heavy-ion collisions are discussed, with special emphasis on using lattice computations to guide the phenomenology of finite temperature hadronic matter. The background rates for continuum dileptons expected in forthcoming experiments are summarised. Properly augmented by data from ongoing measurements at HERA, these rates will serve as a calibrating background for QGP searches. Recent results on the temperature dependence of the hadronic spectrum obtained in lattice computations below the deconfinement transition are summarised. Light vector meson masses are strongly temperature dependent. Accurate measurements of a resolved $\rho$-peak in dimuon spectra in present experiments are thus of fundamental importance. [file-length=200k characters; instructions for processing given; some Latex versions give error messages: ignore them completely]
1402.0628
Gulsheen Ahuja
Samandeep Sharma, Priyanka Fakay, Gulsheen Ahuja, Manmohan Gupta
Implications of non minimal lepton mass textures for Dirac neutrinos
38 pages, 46 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the light of the recent measurement of the leptonic mixing angle $\theta_{13}$, implications of the latest mixing data have been investigated for non-minimal textures of lepton mass matrices pertaining to Dirac neutrinos. All these texture specific lepton mass matrices have been examined for their compatibility with the latest data in the cases of normal hierarchy, inverted hierarchy and degenerate scenario of neutrino masses. The implications of all the three lepton mixing angles have been investigated on the lightest neutrino mass as well as the Jarlskog's CP violating parameter in the leptonic sector.
[ { "created": "Tue, 4 Feb 2014 06:11:17 GMT", "version": "v1" } ]
2014-02-05
[ [ "Sharma", "Samandeep", "" ], [ "Fakay", "Priyanka", "" ], [ "Ahuja", "Gulsheen", "" ], [ "Gupta", "Manmohan", "" ] ]
In the light of the recent measurement of the leptonic mixing angle $\theta_{13}$, implications of the latest mixing data have been investigated for non-minimal textures of lepton mass matrices pertaining to Dirac neutrinos. All these texture specific lepton mass matrices have been examined for their compatibility with the latest data in the cases of normal hierarchy, inverted hierarchy and degenerate scenario of neutrino masses. The implications of all the three lepton mixing angles have been investigated on the lightest neutrino mass as well as the Jarlskog's CP violating parameter in the leptonic sector.
1609.09027
Bennie F. L. Ward
B.F.L. Ward (1) ((1) Baylor University, Waco, TX, USA)
Hard Corrections in Precision QCD for LHC and FCC Physics: A New Approach
6 pages, no figures; based on a talk presented at ICHEP2016, Chicago, IL, USA
null
null
BU-HEPP-16-04
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With an eye toward the usual unphysical divergence of hard fixed-order corrections in predictions for the processes probed in high energy colliding hadron beam devices as one approaches the soft limit, we present a new approach to the realization of such corrections, with some emphasis on the LHC and the future FCC devices. We show that the respective divergence is removed in our approach. This means that we would render the standard results to be closer to the observed exclusive distributions. While we stress that the approach has general applicability, we use the single Z and virtual gamma production and decay to lepton pairs as our prototypical example. Accordingly, our work opens another part of the way to rigorous baselines for the determination of the theoretical precision tags for LHC physics, with an attendant generalization to the future FCC.
[ { "created": "Wed, 28 Sep 2016 18:22:45 GMT", "version": "v1" } ]
2016-09-29
[ [ "Ward", "B. F. L.", "", "Baylor University, Waco, TX, USA" ] ]
With an eye toward the usual unphysical divergence of hard fixed-order corrections in predictions for the processes probed in high energy colliding hadron beam devices as one approaches the soft limit, we present a new approach to the realization of such corrections, with some emphasis on the LHC and the future FCC devices. We show that the respective divergence is removed in our approach. This means that we would render the standard results to be closer to the observed exclusive distributions. While we stress that the approach has general applicability, we use the single Z and virtual gamma production and decay to lepton pairs as our prototypical example. Accordingly, our work opens another part of the way to rigorous baselines for the determination of the theoretical precision tags for LHC physics, with an attendant generalization to the future FCC.
2012.08846
Diana Rojas-Ciofalo
Heather E. Logan, Stefano Moretti, Diana Rojas-Ciofalo, Muyuan Song
CP violation from charged Higgs bosons in the three Higgs doublet model
35 pages, 22 figures. Revised version with a replacement of figures and addition of references
null
10.1007/JHEP07(2021)158
null
hep-ph
http://creativecommons.org/licenses/by-sa/4.0/
We demonstrate a new type of cancellation of contributions to the electron and neutron electric dipole moments (EDMs) that occurs in three Higgs doublet models (3HDMs) when CP violation appears in the charged Higgs sector. The cancellation becomes exact when the two physical charged Higgs bosons in the model are degenerate in mass. Depending on the model parameters, degeneracies at the 10\% level are however sufficient to evade current bounds on the electron and neutron EDMs. We demonstrate that viable parameter space remains with both charged Higgs bosons lighter than 500 GeV and large CP-violating phases while also satisfying theoretical constraints from perturbativity and experimental ones from $\bar{B} \to X_s \gamma$ and direct searches.
[ { "created": "Wed, 16 Dec 2020 10:36:17 GMT", "version": "v1" }, { "created": "Mon, 28 Jun 2021 09:55:30 GMT", "version": "v2" } ]
2021-08-18
[ [ "Logan", "Heather E.", "" ], [ "Moretti", "Stefano", "" ], [ "Rojas-Ciofalo", "Diana", "" ], [ "Song", "Muyuan", "" ] ]
We demonstrate a new type of cancellation of contributions to the electron and neutron electric dipole moments (EDMs) that occurs in three Higgs doublet models (3HDMs) when CP violation appears in the charged Higgs sector. The cancellation becomes exact when the two physical charged Higgs bosons in the model are degenerate in mass. Depending on the model parameters, degeneracies at the 10\% level are however sufficient to evade current bounds on the electron and neutron EDMs. We demonstrate that viable parameter space remains with both charged Higgs bosons lighter than 500 GeV and large CP-violating phases while also satisfying theoretical constraints from perturbativity and experimental ones from $\bar{B} \to X_s \gamma$ and direct searches.
hep-ph/0204352
Walter Winter
Patrick Huber, Manfred Lindner, and Walter Winter
Superbeams versus Neutrino Factories
Revised version with JHF energy resolution corrected, discussion of detector issues added (App. B), and references added. Summary and conclusions unchanged. 51 pages, 28 figures, 4 tables
Nucl.Phys.B645:3-48,2002
10.1016/S0550-3213(02)00825-8
TUM-HEP-462/02, MPI-PhT/02-15
hep-ph hep-ex
null
We compare the physics potential of planned superbeams with the one of neutrino factories. Therefore, the experimental setups as well as the most relevant uncertainties and errors are considered on the same footing as much as possible. We use an improved analysis including the full parameter correlations, as well as statistical, systematical, and degeneracy errors. Especially, degeneracies have so far not been taken into account in a numerical analysis. We furthermore include external input, such as improved knowledge of the solar oscillation parameters from the KamLAND experiment. This allows us to determine the limiting uncertainties in all cases. For a specific comparison, we choose two representatives of each class: For the superbeam, we take the first conceivable setup, namely the JHF to SuperKamiokande experiment, as well as, on a longer time scale, the JHF to HyperKamiokande experiment. For the neutrino factory, we choose an initially conceivable setup and an advanced machine. We determine the potential to measure the small mixing angle sin^2 2 theta_{13}, the sign of Delta m^2_{31}, and the leptonic CP phase $\deltacp$, which also implies that we compare the limitations of the different setups. We find interesting results, such as the complete loss of the sensitivity to the sign of Delta m^2_{31} due to degeneracies in many cases.
[ { "created": "Tue, 30 Apr 2002 13:34:55 GMT", "version": "v1" }, { "created": "Tue, 30 Jul 2002 12:56:06 GMT", "version": "v2" } ]
2014-11-17
[ [ "Huber", "Patrick", "" ], [ "Lindner", "Manfred", "" ], [ "Winter", "Walter", "" ] ]
We compare the physics potential of planned superbeams with the one of neutrino factories. Therefore, the experimental setups as well as the most relevant uncertainties and errors are considered on the same footing as much as possible. We use an improved analysis including the full parameter correlations, as well as statistical, systematical, and degeneracy errors. Especially, degeneracies have so far not been taken into account in a numerical analysis. We furthermore include external input, such as improved knowledge of the solar oscillation parameters from the KamLAND experiment. This allows us to determine the limiting uncertainties in all cases. For a specific comparison, we choose two representatives of each class: For the superbeam, we take the first conceivable setup, namely the JHF to SuperKamiokande experiment, as well as, on a longer time scale, the JHF to HyperKamiokande experiment. For the neutrino factory, we choose an initially conceivable setup and an advanced machine. We determine the potential to measure the small mixing angle sin^2 2 theta_{13}, the sign of Delta m^2_{31}, and the leptonic CP phase $\deltacp$, which also implies that we compare the limitations of the different setups. We find interesting results, such as the complete loss of the sensitivity to the sign of Delta m^2_{31} due to degeneracies in many cases.
2309.10853
Martin Beneke
Martin Beneke (TU Munich), Hiromasa Takaura (Kyoto University)
Gradient-flow renormalon subtraction and the hadronic tau decay series
10 pages, contribution to the Proceedings of the 16th International Symposium on Radiative Corrections: Applications of Quantum Field Theory to Phenomenology (RADCOR2023), 28th May - 2nd June, 2023, Crieff, Scotland, UK
null
null
TUM-HEP-1473/23, YITP-23-116
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The inconsistency between the fixed-order (FO) and contour-improved (CI) representation of the QCD corrections to the inclusive hadronic tau decay width limits the precision to which the strong coupling can be determined from this process. It has recently been shown that subtracting the infrared renormalon divergence related to the gluon condensate resolves the discrepancy. Here we suggest to employ the gradient flow to define gauge-invariant regularized operators and to use the corresponding condensates in the operator product expansion. The associated rearrangement of the perturbative series results in automatic renormalon subtraction without the need to determine explicitly the Stokes constants that normalize the divergent asymptotic series. Applying this method to the gluon condensate, we find that the CI series is modified and now agrees with the (unmodified) FO series. This conclusively demonstrates the preference for the fixed-order approach, as has been advocated long ago.
[ { "created": "Tue, 19 Sep 2023 18:02:30 GMT", "version": "v1" } ]
2023-09-21
[ [ "Beneke", "Martin", "", "TU Munich" ], [ "Takaura", "Hiromasa", "", "Kyoto University" ] ]
The inconsistency between the fixed-order (FO) and contour-improved (CI) representation of the QCD corrections to the inclusive hadronic tau decay width limits the precision to which the strong coupling can be determined from this process. It has recently been shown that subtracting the infrared renormalon divergence related to the gluon condensate resolves the discrepancy. Here we suggest to employ the gradient flow to define gauge-invariant regularized operators and to use the corresponding condensates in the operator product expansion. The associated rearrangement of the perturbative series results in automatic renormalon subtraction without the need to determine explicitly the Stokes constants that normalize the divergent asymptotic series. Applying this method to the gluon condensate, we find that the CI series is modified and now agrees with the (unmodified) FO series. This conclusively demonstrates the preference for the fixed-order approach, as has been advocated long ago.
2303.04168
Guanghui Zhou
Wouter Dekens, Jordy de Vries, Emanuele Mereghetti, Javier Men\'endez, Pablo Soriano, Guanghui Zhou
Neutrinoless double-beta decay in the neutrino-extended Standard Model
8 pages, 3 figures, 2 tables
null
null
LA-UR-23-22287, INT-PUB-23-009
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate neutrinoless double-beta decay ($0\nu\beta\beta$) in the minimal extension of the standard model of particle physics, the $\nu$SM, where gauge-singlet right-handed neutrinos give rise to Dirac and Majorana neutrino mass terms. We focus on the associated sterile neutrinos and argue that the usual evaluation of their contributions to $0\nu\beta\beta$, based on mass-dependent nuclear matrix elements, is missing important contributions from neutrinos with ultrasoft and hard momenta. We identify the hadronic and nuclear matrix elements that enter the new contributions, and calculate all relevant nuclear matrix elements for $^{136}$Xe using the nuclear shell model. Finally, we illustrate the impact on $0\nu\beta\beta$ rates in specific neutrino mass models and show that the new contributions significantly alter the $0\nu\beta\beta$ rate in most parts of the $\nu$SM parameter space.
[ { "created": "Tue, 7 Mar 2023 19:00:02 GMT", "version": "v1" } ]
2023-03-09
[ [ "Dekens", "Wouter", "" ], [ "de Vries", "Jordy", "" ], [ "Mereghetti", "Emanuele", "" ], [ "Menéndez", "Javier", "" ], [ "Soriano", "Pablo", "" ], [ "Zhou", "Guanghui", "" ] ]
We investigate neutrinoless double-beta decay ($0\nu\beta\beta$) in the minimal extension of the standard model of particle physics, the $\nu$SM, where gauge-singlet right-handed neutrinos give rise to Dirac and Majorana neutrino mass terms. We focus on the associated sterile neutrinos and argue that the usual evaluation of their contributions to $0\nu\beta\beta$, based on mass-dependent nuclear matrix elements, is missing important contributions from neutrinos with ultrasoft and hard momenta. We identify the hadronic and nuclear matrix elements that enter the new contributions, and calculate all relevant nuclear matrix elements for $^{136}$Xe using the nuclear shell model. Finally, we illustrate the impact on $0\nu\beta\beta$ rates in specific neutrino mass models and show that the new contributions significantly alter the $0\nu\beta\beta$ rate in most parts of the $\nu$SM parameter space.
hep-ph/9707315
Sourendu Gupta
Sourendu Gupta
Single Polarisation Asymmetries for Quarkonia in Non-relativistic QCD
Plain LaTeX with one figure (ps)
Phys. Rev. D 57, 1858 (1998)
10.1103/PhysRevD.57.1858
TIFR/TH/97-36
hep-ph
null
We find that single spin asymmetries in NRQCD are non-vanishing in general. They are proportional to the imaginary parts of some non-perturbative matrix elements. With statistics of about 10^6 identified J/psi's, or 10^5 identified chi_2, it is possible to measure these imaginary parts even if they are an order of magnitude smaller than the real parts. Such statistics are quite reasonable at polarised HERA N and other future experiments.
[ { "created": "Fri, 11 Jul 1997 20:09:39 GMT", "version": "v1" } ]
2016-08-25
[ [ "Gupta", "Sourendu", "" ] ]
We find that single spin asymmetries in NRQCD are non-vanishing in general. They are proportional to the imaginary parts of some non-perturbative matrix elements. With statistics of about 10^6 identified J/psi's, or 10^5 identified chi_2, it is possible to measure these imaginary parts even if they are an order of magnitude smaller than the real parts. Such statistics are quite reasonable at polarised HERA N and other future experiments.
0712.1031
Ariel Megevand
Ariel Megevand and Alejandro D. Sanchez
Supercooling and phase coexistence in cosmological phase transitions
25 pages, 10 figures. References added and minor corrections. Version to appear in Phys. Rev. D
Phys.Rev.D77:063519,2008
10.1103/PhysRevD.77.063519
null
hep-ph astro-ph hep-th
null
Cosmological phase transitions are predicted by Particle Physics models, and have a variety of important cosmological consequences, which depend strongly on the dynamics of the transition. In this work we investigate in detail the general features of the development of a first-order phase transition. We find thermodynamical constraints on some quantities that determine the dynamics, namely, the latent heat, the radiation energy density and the false-vacuum energy density. Using a simple model with a Higgs field, we study numerically the amount and duration of supercooling and the subsequent reheating and phase coexistence. We analyze the dependence of the dynamics on the different parameters of the model, namely, the energy scale, the number of degrees of freedom and the couplings of the scalar field with bosons and fermions. We also inspect the implications for the cosmological outcomes of the phase transition.
[ { "created": "Thu, 6 Dec 2007 20:26:00 GMT", "version": "v1" }, { "created": "Wed, 12 Dec 2007 20:35:51 GMT", "version": "v2" }, { "created": "Tue, 19 Feb 2008 18:08:03 GMT", "version": "v3" } ]
2008-11-26
[ [ "Megevand", "Ariel", "" ], [ "Sanchez", "Alejandro D.", "" ] ]
Cosmological phase transitions are predicted by Particle Physics models, and have a variety of important cosmological consequences, which depend strongly on the dynamics of the transition. In this work we investigate in detail the general features of the development of a first-order phase transition. We find thermodynamical constraints on some quantities that determine the dynamics, namely, the latent heat, the radiation energy density and the false-vacuum energy density. Using a simple model with a Higgs field, we study numerically the amount and duration of supercooling and the subsequent reheating and phase coexistence. We analyze the dependence of the dynamics on the different parameters of the model, namely, the energy scale, the number of degrees of freedom and the couplings of the scalar field with bosons and fermions. We also inspect the implications for the cosmological outcomes of the phase transition.
2004.10736
Luciano Abreu
L. M. Abreu, F. M. da Costa J\'unior and A. G. Favero
Revisiting the tensor $J^{PC} = 2^{--}$ meson spectrum
21 pages, 6 figures and 5 tables; revised version with updated references
Phys. Rev. D 101, 116016 (2020)
10.1103/PhysRevD.101.116016
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This work is devoted to the discussion and characterization of the tensor $2^{-(-)}$ meson spectrum, by making use of the Coulomb gauge Hamiltonian approach to QCD, with the interactions being given by an improved confining potential and a transverse hyperfine interaction, whose kernel is a Yukawa-type potential. Our aim is to study the basic features of $2^{-(-)}$ mesons within an unified framework through the whole range of quark masses. We concentrate our investigation on predictions of expected but yet-unobserved ground states of unflavored light mesons and on charmonium and bottomonium states. The numerical results are compared with existing literature.
[ { "created": "Wed, 22 Apr 2020 17:40:30 GMT", "version": "v1" }, { "created": "Tue, 16 Jun 2020 13:45:57 GMT", "version": "v2" }, { "created": "Fri, 10 Jul 2020 20:51:23 GMT", "version": "v3" } ]
2020-07-14
[ [ "Abreu", "L. M.", "" ], [ "Júnior", "F. M. da Costa", "" ], [ "Favero", "A. G.", "" ] ]
This work is devoted to the discussion and characterization of the tensor $2^{-(-)}$ meson spectrum, by making use of the Coulomb gauge Hamiltonian approach to QCD, with the interactions being given by an improved confining potential and a transverse hyperfine interaction, whose kernel is a Yukawa-type potential. Our aim is to study the basic features of $2^{-(-)}$ mesons within an unified framework through the whole range of quark masses. We concentrate our investigation on predictions of expected but yet-unobserved ground states of unflavored light mesons and on charmonium and bottomonium states. The numerical results are compared with existing literature.
0704.1417
Antonio Pineda
Jorge Mondejar and Antonio Pineda
Constraints on Regge models from perturbation theory
14 pages, 6 figures; two references added, numerical analysis extended, main conclusions unchanged
JHEP0710:061,2007
10.1088/1126-6708/2007/10/061
UAB-FT-630; UB-ECM-PF-07-07
hep-ph hep-th nucl-th
null
We study the constraints that the operator product expansion imposes on large $N_c$ inspired QCD models for current-current correlators. We focus on the constraints obtained by going beyond the leading-order parton computation. We explicitly show that, assumed a given mass spectrum: linear Regge behavior in $n$ (the principal quantum number) plus corrections in $1/n$, we can obtain the logarithmic (and constant) behavior in $n$ of the decay constants within a systematic expansion in $1/n$. Our example shows that it is possible to have different large $n$ behavior for the vector and pseudo-vector mass spectrum and yet comply with all the constraints from the operator product expansion.
[ { "created": "Wed, 11 Apr 2007 13:48:12 GMT", "version": "v1" }, { "created": "Fri, 13 Apr 2007 18:15:44 GMT", "version": "v2" }, { "created": "Wed, 10 Oct 2007 08:25:04 GMT", "version": "v3" } ]
2008-11-26
[ [ "Mondejar", "Jorge", "" ], [ "Pineda", "Antonio", "" ] ]
We study the constraints that the operator product expansion imposes on large $N_c$ inspired QCD models for current-current correlators. We focus on the constraints obtained by going beyond the leading-order parton computation. We explicitly show that, assumed a given mass spectrum: linear Regge behavior in $n$ (the principal quantum number) plus corrections in $1/n$, we can obtain the logarithmic (and constant) behavior in $n$ of the decay constants within a systematic expansion in $1/n$. Our example shows that it is possible to have different large $n$ behavior for the vector and pseudo-vector mass spectrum and yet comply with all the constraints from the operator product expansion.
0901.0783
Kenji Fukushima
Kenji Fukushima
Isentropic thermodynamics in the PNJL model
9 pages, 9 figures
Phys.Rev.D79:074015,2009
10.1103/PhysRevD.79.074015
YITP-08-84
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the isentropic trajectories on the QCD phase diagram in the temperature and the quark chemical potential plane using the Nambu--Jona-Lasinio model with the Polyakov loop coupling (PNJL model). We impose a constraint on the strange quark chemical potential so that the strange quark density is zero, which is the case in the ultra relativistic heavy-ion collisions. We compare our numerical results with the truncated estimates by the Taylor expansion in terms of the chemical potential to quantify the reliability of the expansion used in the lattice QCD simulation. We finally discuss the strange quark chemical potential induced by the strangeness neutrality condition and relate it to the ratio of the Polyakov loop and the anti-Polyakov loop.
[ { "created": "Wed, 7 Jan 2009 09:10:34 GMT", "version": "v1" } ]
2010-04-14
[ [ "Fukushima", "Kenji", "" ] ]
We discuss the isentropic trajectories on the QCD phase diagram in the temperature and the quark chemical potential plane using the Nambu--Jona-Lasinio model with the Polyakov loop coupling (PNJL model). We impose a constraint on the strange quark chemical potential so that the strange quark density is zero, which is the case in the ultra relativistic heavy-ion collisions. We compare our numerical results with the truncated estimates by the Taylor expansion in terms of the chemical potential to quantify the reliability of the expansion used in the lattice QCD simulation. We finally discuss the strange quark chemical potential induced by the strangeness neutrality condition and relate it to the ratio of the Polyakov loop and the anti-Polyakov loop.
1608.00602
David Fogaca
D. A. Foga\c{c}a, S. M. Sanches Jr., T. F. Motta and F. S. Navarra
Compact stars with strongly coupled quark matter in a strong magnetic field
null
Phys. Rev. C 94, 055805 (2016)
10.1103/PhysRevC.94.055805
null
hep-ph astro-ph.HE nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Some time ago we have derived from the QCD Lagrangian an equation of state (EOS) for the cold quark matter, which can be considered an improved version of the MIT bag model EOS. Compared to the latter, our equation of state reaches higher values of the pressure at comparable baryon densities. This feature is due to perturbative corrections and also to non-perturbative effects. Later we applied this EOS to the study of compact stars, discussing the absolute stability of quark matter and computing the mass-radius relation for self-bound (strange) stars. We found maximum masses of the sequences with more than two solar masses, in agreement with the recent experimental observations. In the present work we include the magnetic field in the equation of state and study how it changes the stability conditions and the mass-radius curves.
[ { "created": "Mon, 1 Aug 2016 20:30:48 GMT", "version": "v1" }, { "created": "Mon, 24 Oct 2016 18:54:28 GMT", "version": "v2" }, { "created": "Wed, 23 Nov 2016 09:18:26 GMT", "version": "v3" } ]
2016-11-24
[ [ "Fogaça", "D. A.", "" ], [ "Sanches", "S. M.", "Jr." ], [ "Motta", "T. F.", "" ], [ "Navarra", "F. S.", "" ] ]
Some time ago we have derived from the QCD Lagrangian an equation of state (EOS) for the cold quark matter, which can be considered an improved version of the MIT bag model EOS. Compared to the latter, our equation of state reaches higher values of the pressure at comparable baryon densities. This feature is due to perturbative corrections and also to non-perturbative effects. Later we applied this EOS to the study of compact stars, discussing the absolute stability of quark matter and computing the mass-radius relation for self-bound (strange) stars. We found maximum masses of the sequences with more than two solar masses, in agreement with the recent experimental observations. In the present work we include the magnetic field in the equation of state and study how it changes the stability conditions and the mass-radius curves.
hep-ph/0002260
Xiao-Gang He
N. G. Deshpande (Oregon), Xiao-Gang He (NTU Taiwan), and Jian-Qing Shi (NTU Taiwan)
SU(3) Flavor Symmetry and CP Violating Rate Differences for Charmless $B\to P V$ Decays
Latex 18 pages. New references and comments added
Phys.Rev.D62:034018,2000
10.1103/PhysRevD.62.034018
null
hep-ph
null
We derive several relations between CP violating rate differences $\Delta(B\to PV) = \Gamma(B\to PV) - \Gamma(\bar B \to \bar P \bar V)$ for charmless $B\to P V$ decays in the Standard Model using SU(3) flavor symmetry. It is found that although the relations between branching ratios of $\Delta S = 0$ and $\Delta S = -1$ processes are complicated, there are simple relations independent of hadronic models between some of the $\Delta S =0$ and $\Delta S = -1$ rate differences due to the unitarity property of the Kobayashi-Maskawa matrix, such as $ \Delta(B\to \pi^+ \rho^-) = -\Delta(B\to \pi^+ K^{*-})$, $\Delta(B\to \pi^- \rho^+) = - \Delta(K^- \rho^+)$. SU(3) breaking effects are also estimated using factorization approximation. These relations can be tested at B factories in the near future.
[ { "created": "Fri, 25 Feb 2000 02:05:04 GMT", "version": "v1" }, { "created": "Thu, 16 Mar 2000 02:25:47 GMT", "version": "v2" } ]
2014-11-17
[ [ "Deshpande", "N. G.", "", "Oregon" ], [ "He", "Xiao-Gang", "", "NTU Taiwan" ], [ "Shi", "Jian-Qing", "", "NTU Taiwan" ] ]
We derive several relations between CP violating rate differences $\Delta(B\to PV) = \Gamma(B\to PV) - \Gamma(\bar B \to \bar P \bar V)$ for charmless $B\to P V$ decays in the Standard Model using SU(3) flavor symmetry. It is found that although the relations between branching ratios of $\Delta S = 0$ and $\Delta S = -1$ processes are complicated, there are simple relations independent of hadronic models between some of the $\Delta S =0$ and $\Delta S = -1$ rate differences due to the unitarity property of the Kobayashi-Maskawa matrix, such as $ \Delta(B\to \pi^+ \rho^-) = -\Delta(B\to \pi^+ K^{*-})$, $\Delta(B\to \pi^- \rho^+) = - \Delta(K^- \rho^+)$. SU(3) breaking effects are also estimated using factorization approximation. These relations can be tested at B factories in the near future.
hep-ph/9601392
Aaron Grant
A. K. Grant, R. D. Peccei, T. Veletto and K. Wang
Speculations on ALEPH's Dijet Enhancement
10 pages, 1 figure
Phys.Lett. B379 (1996) 272-278
10.1016/0370-2693(96)00421-2
UCLA/96/TEP/2
hep-ph
null
We interpret the dijet enhancement reported by the ALEPH collaboration in the process $e^+e^- \rightarrow $ 4 jets as being due to the production of a pair of bottom squarks, followed by their R-parity violating decays into pairs of light quarks. Constraints on this speculative interpretation are examined. Some of the consequences of our hypothesis are drawn within the context of softly broken supersymmetry.
[ { "created": "Wed, 31 Jan 1996 22:42:12 GMT", "version": "v1" } ]
2009-10-28
[ [ "Grant", "A. K.", "" ], [ "Peccei", "R. D.", "" ], [ "Veletto", "T.", "" ], [ "Wang", "K.", "" ] ]
We interpret the dijet enhancement reported by the ALEPH collaboration in the process $e^+e^- \rightarrow $ 4 jets as being due to the production of a pair of bottom squarks, followed by their R-parity violating decays into pairs of light quarks. Constraints on this speculative interpretation are examined. Some of the consequences of our hypothesis are drawn within the context of softly broken supersymmetry.
hep-ph/9803467
Fernando Silveira Navarra
F.S. Navarra and M. Nielsen
$g_{ND\Lambda_{c}}$ from QCD Sum Rules
9 pages, Latex, 5 ps figures
Phys.Lett. B443 (1998) 285-292
10.1016/S0370-2693(98)01247-7
null
hep-ph
null
The $ND\Lambda_c$ coupling constant is evaluated in a full QCD sum rule calculation. We study the Borel sum rule for the three point function of one pseudoscalar one nucleon and one $\Lambda_c$ current up to order seven in the operator product expansion. The Borel transform is performed with respect to the nucleon and $\Lambda_c$ momenta, which are taken to be equal, whereas the momentum $q^2$ of the pseudoscalar vertex is taken to be zero. This coupling constant is relevant in the meson cloud description of the nucleon which has been recently used to explain exotic events observed by the H1 and ZEUS Collaborations at HERA.
[ { "created": "Thu, 26 Mar 1998 21:37:23 GMT", "version": "v1" } ]
2009-10-31
[ [ "Navarra", "F. S.", "" ], [ "Nielsen", "M.", "" ] ]
The $ND\Lambda_c$ coupling constant is evaluated in a full QCD sum rule calculation. We study the Borel sum rule for the three point function of one pseudoscalar one nucleon and one $\Lambda_c$ current up to order seven in the operator product expansion. The Borel transform is performed with respect to the nucleon and $\Lambda_c$ momenta, which are taken to be equal, whereas the momentum $q^2$ of the pseudoscalar vertex is taken to be zero. This coupling constant is relevant in the meson cloud description of the nucleon which has been recently used to explain exotic events observed by the H1 and ZEUS Collaborations at HERA.
1207.0729
York Schroder
M. Maniatis, Y. Schroder
Constraints on the NMSSM from the oblique parameters
11 pages, 7 figures, 1 table
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Electroweak precision measurements, encoded in the oblique parameters, give strong constraints on physics beyond the Standard Model. The oblique parameters S, T, U (V, W, X) are calculated in the next-to-minimal supersymmetric model (NMSSM). We outline the calculation of the oblique parameters in terms of one-loop gauge-boson selfenergies and find sensitive restrictions for the NMSSM parameter space.
[ { "created": "Tue, 3 Jul 2012 16:01:52 GMT", "version": "v1" } ]
2012-07-05
[ [ "Maniatis", "M.", "" ], [ "Schroder", "Y.", "" ] ]
Electroweak precision measurements, encoded in the oblique parameters, give strong constraints on physics beyond the Standard Model. The oblique parameters S, T, U (V, W, X) are calculated in the next-to-minimal supersymmetric model (NMSSM). We outline the calculation of the oblique parameters in terms of one-loop gauge-boson selfenergies and find sensitive restrictions for the NMSSM parameter space.
hep-ph/9803499
null
D. Cocolicchio and M. Viggiano
A model independent and rephase invariant parametrization of CP violation
19 pages, Plain TeX
Int.J.Mod.Phys.A14:4803-4818,1999
10.1142/S0217751X99002268
IFUM-FT 609/98
hep-ph
null
The phenomenological description of the neutral B meson system is proposed in terms of the fundamental CP-violating observables and within a rephasing invariant formalism. This generic formalism can select the time-dependent and time-integrated asymmetries which provide the basic tools to discriminate the different kinds of possible CP-violating effects in dedicated experimental B-meson facilities.
[ { "created": "Tue, 31 Mar 1998 17:26:05 GMT", "version": "v1" } ]
2011-04-12
[ [ "Cocolicchio", "D.", "" ], [ "Viggiano", "M.", "" ] ]
The phenomenological description of the neutral B meson system is proposed in terms of the fundamental CP-violating observables and within a rephasing invariant formalism. This generic formalism can select the time-dependent and time-integrated asymmetries which provide the basic tools to discriminate the different kinds of possible CP-violating effects in dedicated experimental B-meson facilities.
hep-ph/0308242
Hyun-Chul Kim
Hyun-Chul Kim and Michal Praszalowicz
Magnetic moments of exotic pentaquarks in the chiral quark-soliton model
9 pages, 1 figure, submitted to Phys. Lett. B. The title was changed. One sign mistake was removed with the text extended. One author is added
Phys.Lett. B585 (2004) 99-105
10.1016/j.physletb.2004.01.067
PNU-NTG-07/2003, TPJU-10/2003, BNL-NT-03/37
hep-ph nucl-th
null
We investigate the magnetic moments of the baryon antidecuplet within the framework of the chiral quark-soliton model in the chiral limit in a ``\emph{model-independent}'' approach. Sum rules for the magnetic moments are derived. The magnetic moment of $\Theta^{+}$ is found to be about $0.2\sim 0.3 \mu_{N}$.
[ { "created": "Mon, 25 Aug 2003 07:10:38 GMT", "version": "v1" }, { "created": "Sun, 23 Nov 2003 15:41:12 GMT", "version": "v2" } ]
2015-06-25
[ [ "Kim", "Hyun-Chul", "" ], [ "Praszalowicz", "Michal", "" ] ]
We investigate the magnetic moments of the baryon antidecuplet within the framework of the chiral quark-soliton model in the chiral limit in a ``\emph{model-independent}'' approach. Sum rules for the magnetic moments are derived. The magnetic moment of $\Theta^{+}$ is found to be about $0.2\sim 0.3 \mu_{N}$.
2104.02958
Gongjun Choi
Gongjun Choi, Tsutomu T. Yanagida
Gravitino Cosmology Helped by a Right Handed (S)Neutrino
9 pages, 2 figures, 1 table; title changed, accepted version for publication in PLB
Phys.Lett.B 827 (2022) 136954
10.1016/j.physletb.2022.136954
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we discuss interesting scenarios resulting from the interplay between the gravitino and the lightest right-handed (s)neutrino. We consider two gravitino mass regimes vastly separated, that is, $m_{3/2}=\mathcal{O}(100){\rm eV}$ and $m_{3/2}\simeq100{\rm GeV}$. For the former case, a significant amount of the entropy production in the cosmological history to dilute the gravitino relic abundance is unavoidable for consistency with the number of satellite galaxies in the Milky way. We will show that the right-handed (s)neutrino can play the role of the heavy particle whose late time decay provides such an additional radiation. For the later case, the gravitino of $m_{3/2}\simeq100{\rm GeV}$ may resolve the $S_{8}$ tension as a decaying dark matter. We will show how the lightest right-handed neutrino and its superpartner can help the gravitino decaying dark matter be equipped with a long enough life time and mass degeneracy with a massive decay product to address the $S_{8}$ tension.
[ { "created": "Wed, 7 Apr 2021 07:19:13 GMT", "version": "v1" }, { "created": "Tue, 8 Feb 2022 18:06:39 GMT", "version": "v2" } ]
2022-02-21
[ [ "Choi", "Gongjun", "" ], [ "Yanagida", "Tsutomu T.", "" ] ]
In this paper, we discuss interesting scenarios resulting from the interplay between the gravitino and the lightest right-handed (s)neutrino. We consider two gravitino mass regimes vastly separated, that is, $m_{3/2}=\mathcal{O}(100){\rm eV}$ and $m_{3/2}\simeq100{\rm GeV}$. For the former case, a significant amount of the entropy production in the cosmological history to dilute the gravitino relic abundance is unavoidable for consistency with the number of satellite galaxies in the Milky way. We will show that the right-handed (s)neutrino can play the role of the heavy particle whose late time decay provides such an additional radiation. For the later case, the gravitino of $m_{3/2}\simeq100{\rm GeV}$ may resolve the $S_{8}$ tension as a decaying dark matter. We will show how the lightest right-handed neutrino and its superpartner can help the gravitino decaying dark matter be equipped with a long enough life time and mass degeneracy with a massive decay product to address the $S_{8}$ tension.
hep-ph/9901278
Mikolaj Misiak
Mikolaj Misiak and Joerg Urban
QCD corrections to FCNC decays mediated by Z-penguins and W-boxes
12 pages, latex, 7 ps figures
Phys.Lett.B451:161-169,1999
10.1016/S0370-2693(99)00150-1
TUM-HEP-336/98, IFT-14/98
hep-ph
null
QCD corrections are evaluated to FCNC processes like $B \to X_s \nu \bar{\nu}$, $K \to \pi \nu \bar{\nu}$, $B \to l^+ l^-$ or $K_L \to \mu^+ \mu^-$, i.e. to processes mediated by effective operators containing neutrino currents or axial leptonic currents. Such operators originate from $W$-box and $Z$-penguin diagrams in the Standard Model. QCD corrections to them are given by two-loop diagrams. We confirm results for those diagrams which are already present in the literature. However, our analytical expressions for the Wilson coefficients disagree, due to a subtlety in regulating spurious IR divergences. The numerical effect of the disagreement is rather small. The size of the perturbative QCD corrections compared to the leading terms depends on the renormalization scheme used at the leading order. It varies from 0 to around 15% for a reasonable class of schemes. The uncertainty originating from uncalculated higher-order (three-loop) QCD corrections is expected to be around 1% .
[ { "created": "Tue, 12 Jan 1999 13:24:53 GMT", "version": "v1" } ]
2008-11-26
[ [ "Misiak", "Mikolaj", "" ], [ "Urban", "Joerg", "" ] ]
QCD corrections are evaluated to FCNC processes like $B \to X_s \nu \bar{\nu}$, $K \to \pi \nu \bar{\nu}$, $B \to l^+ l^-$ or $K_L \to \mu^+ \mu^-$, i.e. to processes mediated by effective operators containing neutrino currents or axial leptonic currents. Such operators originate from $W$-box and $Z$-penguin diagrams in the Standard Model. QCD corrections to them are given by two-loop diagrams. We confirm results for those diagrams which are already present in the literature. However, our analytical expressions for the Wilson coefficients disagree, due to a subtlety in regulating spurious IR divergences. The numerical effect of the disagreement is rather small. The size of the perturbative QCD corrections compared to the leading terms depends on the renormalization scheme used at the leading order. It varies from 0 to around 15% for a reasonable class of schemes. The uncertainty originating from uncalculated higher-order (three-loop) QCD corrections is expected to be around 1% .
1905.09553
Carlos Louren\c{c}o
Pietro Faccioli and Carlos Lourenco
NRQCD colour-octet expansion vs LHC quarkonium production: signs of a hierarchy puzzle?
To appear in European Physical Journal C
null
10.1140/epjc/s10052-019-6968-0
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The observation of unpolarized quarkonium production in high energy pp collisions, at mid rapidity, implies a significant violation of the non-relativistic QCD (NRQCD) velocity scaling rules. A precise experimental confirmation of this picture could definitely rule out the current formulation of the factorization expansion. This conclusion relies on current perturbative determinations of the short-distance kinematic factors and may be reverted if improved calculations would modify, in a very specific way, their transverse momentum dependences. That solution would result, however, in a full degeneracy in the presently assumed basis of $^{2S+1}L_J$ Fock states. Therefore, whatever the outcome, improved polarization measurements will challenge and improve our fundamental understanding of quarkonium production.
[ { "created": "Thu, 23 May 2019 09:37:48 GMT", "version": "v1" } ]
2019-06-26
[ [ "Faccioli", "Pietro", "" ], [ "Lourenco", "Carlos", "" ] ]
The observation of unpolarized quarkonium production in high energy pp collisions, at mid rapidity, implies a significant violation of the non-relativistic QCD (NRQCD) velocity scaling rules. A precise experimental confirmation of this picture could definitely rule out the current formulation of the factorization expansion. This conclusion relies on current perturbative determinations of the short-distance kinematic factors and may be reverted if improved calculations would modify, in a very specific way, their transverse momentum dependences. That solution would result, however, in a full degeneracy in the presently assumed basis of $^{2S+1}L_J$ Fock states. Therefore, whatever the outcome, improved polarization measurements will challenge and improve our fundamental understanding of quarkonium production.
hep-ph/0005244
Concha Gonzalez-Garcia
A.A. Bykov, M.C. Gonzalez-Garcia, C. Pe\~na-Garay, V.Yu. Popov, and V.B. Semikoz
MSW Solutions to the Solar Neutrino Problem in Presence of Noisy Matter Density Fluctuations
26 pages, RevTex and 10 postscript files for figures (bitmapped for compression). A full version of the paper can be found at http://ific.uv.es/~penya
null
null
IFIC/00-27
hep-ph astro-ph hep-ex
null
We study the effect of random matter density fluctuations in the sun on resonant neutrino conversion in matter by solving numerically the evolution equation for the neutrino system including the full effect of the random matter density fluctuations of given amplitude and correlation length. In order to establish the possible effect on the MSW solutions to the solar neutrino problem we perform a global analysis of all the existing observables including the measured total rates as well as the Super-Kamiokande measurement on the time dependence of the event rates during the day and night and the recoil electron energy spectrum. We find the effects of random noise to be larger for small mixing angles and they are mostly important for correlation lengths in the range few 100 km $\lesssim L_0\lesssim$ few 1000 km. They can be understood as due to a parametric resonance occuring when the phase acquired by the oscillating neutrino state on one fluctuation length L_0 is a multiple of 2$\pi$. We find that this resonant parametric condition is mainly achieved for low energy neutrinos such as the pp-neutrinos and therefore its effect is mostly seen on the total event rates while the other Super-Kamiokande observables are very marginally sensitive to the presence of noise due to the higher energy threshold.
[ { "created": "Wed, 24 May 2000 17:14:05 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bykov", "A. A.", "" ], [ "Gonzalez-Garcia", "M. C.", "" ], [ "Peña-Garay", "C.", "" ], [ "Popov", "V. Yu.", "" ], [ "Semikoz", "V. B.", "" ] ]
We study the effect of random matter density fluctuations in the sun on resonant neutrino conversion in matter by solving numerically the evolution equation for the neutrino system including the full effect of the random matter density fluctuations of given amplitude and correlation length. In order to establish the possible effect on the MSW solutions to the solar neutrino problem we perform a global analysis of all the existing observables including the measured total rates as well as the Super-Kamiokande measurement on the time dependence of the event rates during the day and night and the recoil electron energy spectrum. We find the effects of random noise to be larger for small mixing angles and they are mostly important for correlation lengths in the range few 100 km $\lesssim L_0\lesssim$ few 1000 km. They can be understood as due to a parametric resonance occuring when the phase acquired by the oscillating neutrino state on one fluctuation length L_0 is a multiple of 2$\pi$. We find that this resonant parametric condition is mainly achieved for low energy neutrinos such as the pp-neutrinos and therefore its effect is mostly seen on the total event rates while the other Super-Kamiokande observables are very marginally sensitive to the presence of noise due to the higher energy threshold.
hep-ph/9801283
Javier Magnin
H.R. Christiansen and J. Magnin
Strange / anti-strange asymmetry in the nucleon sea
Modified version, several improvements. To appear in Phys. Lett. B
Phys.Lett. B445 (1998) 8-13
10.1016/S0370-2693(98)01460-9
CBPF-NF-003/98
hep-ph hep-ex nucl-th
null
We analyze the non-perturbative structure of the strange sea of the nucleon within a meson cloud picture. In a low $Q^2$ approach in which the nucleon is viewed as a three valon bound state, we evaluate the probability distribution of an in-nucleon Kaon-Hyperon pair in terms of splitting functions and recombination. The resulting kaon and hyperon probability densities are convoluted with suitable strange distributions inside the meson and baryon in order to obtain non-perturbative contributions to the strange sea of the nucleon. We find a structured strange/anti-strange asymmetry, displaying a clear excess of quarks (anti-quarks) for large (small) momentum fractions
[ { "created": "Tue, 13 Jan 1998 17:56:51 GMT", "version": "v1" }, { "created": "Wed, 25 Nov 1998 12:03:31 GMT", "version": "v2" } ]
2009-10-31
[ [ "Christiansen", "H. R.", "" ], [ "Magnin", "J.", "" ] ]
We analyze the non-perturbative structure of the strange sea of the nucleon within a meson cloud picture. In a low $Q^2$ approach in which the nucleon is viewed as a three valon bound state, we evaluate the probability distribution of an in-nucleon Kaon-Hyperon pair in terms of splitting functions and recombination. The resulting kaon and hyperon probability densities are convoluted with suitable strange distributions inside the meson and baryon in order to obtain non-perturbative contributions to the strange sea of the nucleon. We find a structured strange/anti-strange asymmetry, displaying a clear excess of quarks (anti-quarks) for large (small) momentum fractions
hep-ph/0408164
Naveen Gaur
A. S. Cornell and Naveen Gaur
Lepton polarization asymmetries for $B \to K^* \ell^+ \ell^-$: A Model Independent approach
version accepted in JHEP, formating changed to JHEP style, LaTeX file 23 pages including 15 eps figures
JHEP 0502:005,2005
10.1088/1126-6708/2005/02/005
null
hep-ph
null
In this work we shall derive expressions for the single and double lepton polarization asymmetries for the exclusive decay $B \to K^* \ell^+ \ell^-$, using the most general model independent effective Hamiltonian. We have conducted this study with this particular channel as it has the highest branching ratio among the various purely leptonic and semi-leptonic decay modes, making this mode particularly useful for studying physics beyond the SM. We have also analyzed the effects on these polarization asymmetries, and hence the physics underlying it, when complex phases are included in some of the Wilson coefficients.
[ { "created": "Mon, 16 Aug 2004 04:40:25 GMT", "version": "v1" }, { "created": "Fri, 4 Feb 2005 09:01:53 GMT", "version": "v2" } ]
2010-02-03
[ [ "Cornell", "A. S.", "" ], [ "Gaur", "Naveen", "" ] ]
In this work we shall derive expressions for the single and double lepton polarization asymmetries for the exclusive decay $B \to K^* \ell^+ \ell^-$, using the most general model independent effective Hamiltonian. We have conducted this study with this particular channel as it has the highest branching ratio among the various purely leptonic and semi-leptonic decay modes, making this mode particularly useful for studying physics beyond the SM. We have also analyzed the effects on these polarization asymmetries, and hence the physics underlying it, when complex phases are included in some of the Wilson coefficients.
0706.0589
Cai-Dian Lu
Cai-Dian Lu
QCD in hadronic B decays
7 pages, with 1 figure, proceedings of the International Conference On Nonperturbative Quantum Field Theory: Lattice And Beyond, 18-20 Dec 2004, Guangzhou, Canton, China
Mod.Phys.Lett.A22:615-621,2007
10.1142/S0217732307023201
null
hep-ph
null
The perturbative QCD approach is based on $k_T$ factorization, including the Sudakov form factors so that to avoid the endpoint singularity. In this approach, we calculate the charmless B decays like $B\to \pi\pi$ decays etc. to produce the right number of branching ratios and also CP asymmetry parameters. For final states with at least one charmed meson, like $B\to D\pi$ decays, our results also agree with the experiments.
[ { "created": "Tue, 5 Jun 2007 07:05:25 GMT", "version": "v1" } ]
2008-11-26
[ [ "Lu", "Cai-Dian", "" ] ]
The perturbative QCD approach is based on $k_T$ factorization, including the Sudakov form factors so that to avoid the endpoint singularity. In this approach, we calculate the charmless B decays like $B\to \pi\pi$ decays etc. to produce the right number of branching ratios and also CP asymmetry parameters. For final states with at least one charmed meson, like $B\to D\pi$ decays, our results also agree with the experiments.
2210.04125
Pei-Cheng Jiang
Pei-Cheng Jiang, Xuan Wang, Da-Yong Wang
Test of quantum nonlocality via vector meson decays to $K_SK_S$
7 pages, 3 figures, 1 table
Int. J. Mod. Phys. A 36, 2150178 (2021)
10.1142/S0217751X21501785
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the system of a pair of quantum-entangled neutral kaons from meson decays, when one kaon collapses into the $K_S$ state, the other will collapse instantaneously into the $K_L$ state due to entanglement and nonlocality. However, if the alternative hypothesis is correct and there's a time window during which one kaon is unaware that the other has decayed, some quantum mechanically prohibited $K_SK_S$ decays may occur. We calculate the branching ratios of $K_SK_S$ in vector meson decays under the locality hypothesis and compare them with experimental results. We show that the branching ratio of $J/\psi\rightarrow K_SK_S$ under locality assumption is already excluded by the BESIII experimental upper limit. Additional experimental results are proposed to perform this test in the future.
[ { "created": "Sun, 9 Oct 2022 00:14:54 GMT", "version": "v1" }, { "created": "Mon, 7 Nov 2022 10:15:42 GMT", "version": "v2" } ]
2022-11-08
[ [ "Jiang", "Pei-Cheng", "" ], [ "Wang", "Xuan", "" ], [ "Wang", "Da-Yong", "" ] ]
In the system of a pair of quantum-entangled neutral kaons from meson decays, when one kaon collapses into the $K_S$ state, the other will collapse instantaneously into the $K_L$ state due to entanglement and nonlocality. However, if the alternative hypothesis is correct and there's a time window during which one kaon is unaware that the other has decayed, some quantum mechanically prohibited $K_SK_S$ decays may occur. We calculate the branching ratios of $K_SK_S$ in vector meson decays under the locality hypothesis and compare them with experimental results. We show that the branching ratio of $J/\psi\rightarrow K_SK_S$ under locality assumption is already excluded by the BESIII experimental upper limit. Additional experimental results are proposed to perform this test in the future.
1302.3836
Philip Rau
P. Rau, J. Steinheimer, S. Schramm, H. St\"ocker
Chiral Hadronic Mean Field Model including Quark Degrees of Freedom
25 pages, 10 figures
J. Phys. G: Nucl. Part. Phys. 40, 085001 (2013)
10.1088/0954-3899/40/8/085001
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In an approach inspired by Polyakov loop extended NJL models, we present a nonlinear hadronic SU(3) sigma-omega mean field model augmented by quark degrees of freedom. By introducing the effective Polyakov loop related scalar field \Phi and an associated effective potential, the model includes all known hadronic degrees of freedom at low temperatures and densities as well as a quark phase at high temperatures and densities. Hadrons in the model exhibit a finite volume in order to suppress baryons at high T and \mu. This ensures that the right asymptotic degrees of freedom are attained for the description of strongly interacting matter and allows to study the QCD phase diagram in a wide range of temperatures and chemical potentials. Therefore, with this model it is possible to study the phase transition of chiral restoration and deconfinement. In this paper, the impact of quarks on the resulting phase diagram is shown. The results from the chiral model are compared to recent data from lattice QCD.
[ { "created": "Fri, 15 Feb 2013 18:23:40 GMT", "version": "v1" }, { "created": "Fri, 21 Jun 2013 06:56:52 GMT", "version": "v2" } ]
2013-06-24
[ [ "Rau", "P.", "" ], [ "Steinheimer", "J.", "" ], [ "Schramm", "S.", "" ], [ "Stöcker", "H.", "" ] ]
In an approach inspired by Polyakov loop extended NJL models, we present a nonlinear hadronic SU(3) sigma-omega mean field model augmented by quark degrees of freedom. By introducing the effective Polyakov loop related scalar field \Phi and an associated effective potential, the model includes all known hadronic degrees of freedom at low temperatures and densities as well as a quark phase at high temperatures and densities. Hadrons in the model exhibit a finite volume in order to suppress baryons at high T and \mu. This ensures that the right asymptotic degrees of freedom are attained for the description of strongly interacting matter and allows to study the QCD phase diagram in a wide range of temperatures and chemical potentials. Therefore, with this model it is possible to study the phase transition of chiral restoration and deconfinement. In this paper, the impact of quarks on the resulting phase diagram is shown. The results from the chiral model are compared to recent data from lattice QCD.
1411.4529
Mart\'in Gonz\'alez-Alonso
Mart\'in Gonz\'alez-Alonso
TAU2014 Opening Talk
Written version of the Opening Talk at the 13th International Workshop on Tau Lepton Physics (TAU2014), Sept 2014, Aachen, Germany
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Different aspects of Tau physics are discussed, both as a New Physics probe and as a tool to study Standard Model physics. The goal of this Tau2014 opening talk is to introduce (some of) the many research directions currently being pursued with tau leptons, which will be discussed in great technical detail in the following talks.
[ { "created": "Mon, 17 Nov 2014 16:19:39 GMT", "version": "v1" } ]
2014-11-18
[ [ "González-Alonso", "Martín", "" ] ]
Different aspects of Tau physics are discussed, both as a New Physics probe and as a tool to study Standard Model physics. The goal of this Tau2014 opening talk is to introduce (some of) the many research directions currently being pursued with tau leptons, which will be discussed in great technical detail in the following talks.
1005.3798
Tianjun Li
Tianjun Li, Dimitri V. Nanopoulos
General Gauge and Anomaly Mediated Supersymmetry Breaking in Grand Unified Theories with Vector-Like Particles
RevTex4, 45 pages, 15 tables, version to appear in JHEP
null
10.1007/JHEP10(2011)090
ACT-07-10, MIFPA-10-21
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In Grand Unified Theories (GUTs) from orbifold and various string constructions the generic vector-like particles do not need to form complete SU(5) or SO(10) representations. To realize them concretely, we present orbifold SU(5) models, orbifold SO(10) models where the gauge symmetry can be broken down to flipped SU(5) X U(1)_X or Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R gauge symmetries, and F-theory SU(5) models. Interestingly, these vector-like particles can be at the TeV-scale so that the lightest CP-even Higgs boson mass can be lifted, or play the messenger fields in the Gauge Mediated Supersymmetry Breaking (GMSB). Considering GMSB, ultraviolet insensitive Anomaly Mediated Supersymmetry Breaking (AMSB), and the deflected AMSB, we study the general gaugino mass relations and their indices, which are valid from the GUT scale to the electroweak scale at one loop, in the SU(5) models, the flipped SU(5) X U(1)_X models, and the Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R models. In the deflected AMSB, we also define the new indices for the gaugino mass relations, and calculate them as well. Using these gaugino mass relations and their indices, we may probe the messenger fields at intermediate scale in the GMSB and deflected AMSB, determine the supersymmetry breaking mediation mechanisms, and distinguish the four-dimensional GUTs, orbifold GUTs, and F-theory GUTs.
[ { "created": "Thu, 20 May 2010 19:24:07 GMT", "version": "v1" }, { "created": "Mon, 10 Oct 2011 20:02:44 GMT", "version": "v2" } ]
2015-05-19
[ [ "Li", "Tianjun", "" ], [ "Nanopoulos", "Dimitri V.", "" ] ]
In Grand Unified Theories (GUTs) from orbifold and various string constructions the generic vector-like particles do not need to form complete SU(5) or SO(10) representations. To realize them concretely, we present orbifold SU(5) models, orbifold SO(10) models where the gauge symmetry can be broken down to flipped SU(5) X U(1)_X or Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R gauge symmetries, and F-theory SU(5) models. Interestingly, these vector-like particles can be at the TeV-scale so that the lightest CP-even Higgs boson mass can be lifted, or play the messenger fields in the Gauge Mediated Supersymmetry Breaking (GMSB). Considering GMSB, ultraviolet insensitive Anomaly Mediated Supersymmetry Breaking (AMSB), and the deflected AMSB, we study the general gaugino mass relations and their indices, which are valid from the GUT scale to the electroweak scale at one loop, in the SU(5) models, the flipped SU(5) X U(1)_X models, and the Pati-Salam SU(4)_C X SU(2)_L X SU(2)_R models. In the deflected AMSB, we also define the new indices for the gaugino mass relations, and calculate them as well. Using these gaugino mass relations and their indices, we may probe the messenger fields at intermediate scale in the GMSB and deflected AMSB, determine the supersymmetry breaking mediation mechanisms, and distinguish the four-dimensional GUTs, orbifold GUTs, and F-theory GUTs.
hep-ph/0506157
Felix Riek
Yu. B. Ivanov (1 and 2), F. Riek (1), H. van Hees (3), J. Knoll (1) ((1) GSI Darmstadt, (2) Kurchatov Institute Moscow, (3) Texas A&M University)
Renormalization of a gapless Hartree-Fock approximation to a theory with spontaneously broken O(N)-symmetry
11 pages, 14 figures / Version accepted by Phys. Rev. D: title and one reference changed
Phys.Rev. D72 (2005) 036008
10.1103/PhysRevD.72.036008
null
hep-ph cond-mat.other nucl-th
null
The renormalization of a gapless Phi-derivable Hartree--Fock approximation to the O(N)-symmetric lambda*phi^4 theory is considered in the spontaneously broken phase. This kind of approach was proposed by three of us in a previous paper in order to preserve all the desirable features of Phi-derivable Dyson-Schwinger resummation schemes (i.e., validity of conservation laws and thermodynamic consistency) while simultaneously restoring the Nambu--Goldstone theorem in the broken phase. It is shown that unlike for the conventional Hartree--Fock approximation this approach allows for a scale-independent renormalization in the vacuum. However, the scale dependence still persists at finite temperatures. Various branches of the solution are studied. The occurrence of a limiting temperature inherent in the renormalized Hartree--Fock approximation at fixed renormalization scale mu is discussed.
[ { "created": "Thu, 16 Jun 2005 07:25:07 GMT", "version": "v1" }, { "created": "Tue, 9 Aug 2005 08:01:33 GMT", "version": "v2" } ]
2009-11-11
[ [ "Ivanov", "Yu. B.", "", "1 and 2" ], [ "Riek", "F.", "", "GSI Darmstadt" ], [ "van Hees", "H.", "", "Texas A&M University" ], [ "Knoll", "J.", "", "GSI Darmstadt" ] ]
The renormalization of a gapless Phi-derivable Hartree--Fock approximation to the O(N)-symmetric lambda*phi^4 theory is considered in the spontaneously broken phase. This kind of approach was proposed by three of us in a previous paper in order to preserve all the desirable features of Phi-derivable Dyson-Schwinger resummation schemes (i.e., validity of conservation laws and thermodynamic consistency) while simultaneously restoring the Nambu--Goldstone theorem in the broken phase. It is shown that unlike for the conventional Hartree--Fock approximation this approach allows for a scale-independent renormalization in the vacuum. However, the scale dependence still persists at finite temperatures. Various branches of the solution are studied. The occurrence of a limiting temperature inherent in the renormalized Hartree--Fock approximation at fixed renormalization scale mu is discussed.
hep-ph/0108204
Athar Hussain
H. Athar (NCTS,NCTU), Guey-Lin Lin (NCTU)
Implications of $\bar{\nu}_{e}e^{-}\to W^{-}\gamma$ for high-energy $\bar{\nu}_e$ observation
9 pages, 3 figures, RevTex
Astropart.Phys.19:569-574,2003
10.1016/S0927-6505(03)00105-1
NCTU-HEP-0104
hep-ph astro-ph
null
Absorption of high-energy $\bar{\nu}_e$ over electrons above the W boson production threshold is reexamined. It is pointed out that, in the case of photon emissions along the direction of incident high-energy $\bar{\nu}_e$, the kinematically allowed average energy carried by the final state hard photon can be $\leq 1%$ of the incident $\bar{\nu}_e$ energy above the W boson production threshold. The differential energy spectrum for the final state hard photon is calculated. We also discuss implications of our results for the prospective search of high-energy $\bar{\nu}_e$ through this final state hard photon.
[ { "created": "Fri, 24 Aug 2001 11:43:13 GMT", "version": "v1" } ]
2011-05-23
[ [ "Athar", "H.", "", "NCTS,NCTU" ], [ "Lin", "Guey-Lin", "", "NCTU" ] ]
Absorption of high-energy $\bar{\nu}_e$ over electrons above the W boson production threshold is reexamined. It is pointed out that, in the case of photon emissions along the direction of incident high-energy $\bar{\nu}_e$, the kinematically allowed average energy carried by the final state hard photon can be $\leq 1%$ of the incident $\bar{\nu}_e$ energy above the W boson production threshold. The differential energy spectrum for the final state hard photon is calculated. We also discuss implications of our results for the prospective search of high-energy $\bar{\nu}_e$ through this final state hard photon.
1305.7246
Farinaldo Queiroz
W. Caetano, C. A. de S. Pires, P. S. Rodrigues da Silva, D. Cogollo, and Farinaldo S. Queiroz
Explaining ATLAS and CMS Results Within the Reduced Minimal 3-3-1 model
23 pages, 9 figures. References added
null
10.1140/epjc/s10052-013-2607-3
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently the ATLAS and CMS collaborations announced the discovery of a higgs particle with a mass of $\sim 125$ GeV. The results are mildly consistent with the Standard Model Higgs boson. However, the combined data from these collaborations seem to point to an excess in the $h \rightarrow \gamma \gamma$ channel. In this work we analyze under which conditions this excess may be plausibly explained within the reduced minimal 3-3-1 model, while being consistent with bb, WW, ZZ and $\tau^+\tau^-$ channels. Moreover, we derive the properties of the heavy neutral and the doubly charged scalars predicted by the model. We then conclude that at a scale of a few TeV, this model provides a good fit to the ATLAS and CMS signal strength measurements, and therefore stands as an appealing alternative to the standard model.
[ { "created": "Thu, 30 May 2013 20:25:23 GMT", "version": "v1" }, { "created": "Tue, 4 Jun 2013 22:06:05 GMT", "version": "v2" } ]
2015-06-16
[ [ "Caetano", "W.", "" ], [ "Pires", "C. A. de S.", "" ], [ "da Silva", "P. S. Rodrigues", "" ], [ "Cogollo", "D.", "" ], [ "Queiroz", "Farinaldo S.", "" ] ]
Recently the ATLAS and CMS collaborations announced the discovery of a higgs particle with a mass of $\sim 125$ GeV. The results are mildly consistent with the Standard Model Higgs boson. However, the combined data from these collaborations seem to point to an excess in the $h \rightarrow \gamma \gamma$ channel. In this work we analyze under which conditions this excess may be plausibly explained within the reduced minimal 3-3-1 model, while being consistent with bb, WW, ZZ and $\tau^+\tau^-$ channels. Moreover, we derive the properties of the heavy neutral and the doubly charged scalars predicted by the model. We then conclude that at a scale of a few TeV, this model provides a good fit to the ATLAS and CMS signal strength measurements, and therefore stands as an appealing alternative to the standard model.
hep-ph/0702001
Gabriel Shaughnessy
Vernon Barger, Paul Langacker and Gabe Shaughnessy
TeV physics and the Planck scale
17 pages, 5 figures. To appear in New Journal of Physics
New J.Phys.9:333,2007
10.1088/1367-2630/9/9/333
MADPH-07-1479
hep-ph
null
Supersymmetry is one of the best motivated possibilities for new physics at the TeV scale. However, both concrete string constructions and phenomenological considerations suggest the possibility that the physics at the TeV scale could be more complicated than the Minimal Supersymmetric Standard Model (MSSM), e.g., due to extended gauge symmetries, new vector-like supermultiplets with non-standard SU(2)xU(1) assignments, and extended Higgs sectors. We briefly comment on some of these possibilities, and discuss in more detail the class of extensions of the MSSM involving an additional standard model singlet field. The latter provides a solution to the $\mu$ problem, and allows significant modifications of the MSSM in the Higgs and neutralino sectors, with important consequences for collider physics, cold dark matter, and electroweak baryogenesis.
[ { "created": "Wed, 31 Jan 2007 21:00:16 GMT", "version": "v1" } ]
2009-01-06
[ [ "Barger", "Vernon", "" ], [ "Langacker", "Paul", "" ], [ "Shaughnessy", "Gabe", "" ] ]
Supersymmetry is one of the best motivated possibilities for new physics at the TeV scale. However, both concrete string constructions and phenomenological considerations suggest the possibility that the physics at the TeV scale could be more complicated than the Minimal Supersymmetric Standard Model (MSSM), e.g., due to extended gauge symmetries, new vector-like supermultiplets with non-standard SU(2)xU(1) assignments, and extended Higgs sectors. We briefly comment on some of these possibilities, and discuss in more detail the class of extensions of the MSSM involving an additional standard model singlet field. The latter provides a solution to the $\mu$ problem, and allows significant modifications of the MSSM in the Higgs and neutralino sectors, with important consequences for collider physics, cold dark matter, and electroweak baryogenesis.
1301.6895
Asmita Mukherjee
Asmita Mukherjee, Sreeraj Nair, Vikash Kumar Ojha
Generalized Parton Distributions of the Photon with Helicity Flip
Minor changes, version to appear in Phys. Lett. B
null
10.1016/j.physletb.2013.03.031
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a calculation of the generalized parton distributions (GPDs) of the photon when the helicity of the initial photon is different from the final photon. We calculate the GPDs using overlaps of photon light-front wave functions (LFWFs) at leading order in electromagnetic coupling $\alpha$ and zeroth order in the strong coupling $\alpha_s$, when the momentum transfer is purely in the transverse direction. These involve a contribution of orbital angular momentum of two units in the LFWFs. We express these GPDs in the impact parameter space.
[ { "created": "Tue, 29 Jan 2013 11:31:24 GMT", "version": "v1" }, { "created": "Thu, 31 Jan 2013 14:43:45 GMT", "version": "v2" }, { "created": "Sat, 23 Mar 2013 04:53:39 GMT", "version": "v3" } ]
2015-06-12
[ [ "Mukherjee", "Asmita", "" ], [ "Nair", "Sreeraj", "" ], [ "Ojha", "Vikash Kumar", "" ] ]
We present a calculation of the generalized parton distributions (GPDs) of the photon when the helicity of the initial photon is different from the final photon. We calculate the GPDs using overlaps of photon light-front wave functions (LFWFs) at leading order in electromagnetic coupling $\alpha$ and zeroth order in the strong coupling $\alpha_s$, when the momentum transfer is purely in the transverse direction. These involve a contribution of orbital angular momentum of two units in the LFWFs. We express these GPDs in the impact parameter space.
1311.1520
Pedro Miguel Martins Ferreira
A. Arhrib, P.M. Ferreira and R. Santos
Are There Hidden Scalars in LHC Higgs Results?
15 pages, 9 figures. V2: off-shell decays considered, minor changes to comply with referee. V3: replaced plot for correct version
null
10.1007/JHEP03(2014)053
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Higgs boson recently discovered at the Large Hadron Collider has shown to have couplings to the remaining particles well within what is predicted by the Standard Model. The search for other new heavy scalar states has so far revealed to be fruitless, imposing constraints on the existence of new scalar particles. However, it is still possible that any existing heavy scalars would preferentially decay to final states involving the light Higgs boson thus evading the current LHC bounds on heavy scalar states. Moreover, decays of the heavy scalars could increase the number of light Higgs bosons being produced. Since the number of light Higgs bosons decaying to Standard Model particles is within the predicted range, this could mean that part of the light Higgs bosons could have their origin in heavy scalar decays. This situation would occur if the light Higgs couplings to Standard Model particles were reduced by a concomitant amount. Using a very simple extension of the SM - the two-Higgs double model - we show that in fact we could already be observing the effect of the heavy scalar states even if all results related to the Higgs are in excellent agreement with the Standard Model predictions.
[ { "created": "Wed, 6 Nov 2013 21:02:38 GMT", "version": "v1" }, { "created": "Tue, 17 Dec 2013 13:52:08 GMT", "version": "v2" }, { "created": "Wed, 18 Dec 2013 14:56:28 GMT", "version": "v3" }, { "created": "Wed, 29 Jan 2014 16:28:13 GMT", "version": "v4" }, { "created": "Mon, 10 Feb 2014 19:03:41 GMT", "version": "v5" } ]
2015-06-17
[ [ "Arhrib", "A.", "" ], [ "Ferreira", "P. M.", "" ], [ "Santos", "R.", "" ] ]
The Higgs boson recently discovered at the Large Hadron Collider has shown to have couplings to the remaining particles well within what is predicted by the Standard Model. The search for other new heavy scalar states has so far revealed to be fruitless, imposing constraints on the existence of new scalar particles. However, it is still possible that any existing heavy scalars would preferentially decay to final states involving the light Higgs boson thus evading the current LHC bounds on heavy scalar states. Moreover, decays of the heavy scalars could increase the number of light Higgs bosons being produced. Since the number of light Higgs bosons decaying to Standard Model particles is within the predicted range, this could mean that part of the light Higgs bosons could have their origin in heavy scalar decays. This situation would occur if the light Higgs couplings to Standard Model particles were reduced by a concomitant amount. Using a very simple extension of the SM - the two-Higgs double model - we show that in fact we could already be observing the effect of the heavy scalar states even if all results related to the Higgs are in excellent agreement with the Standard Model predictions.
hep-ph/0206298
Igor Ivanov
I.P.Ivanov (1 and 2) and N.N.Nikolaev (1 and 3) ((1) IKP, Forschungszentrum Juelich, Germany, (2) Novosibirsk State University, Russia, (3) Landau ITP, Moscow, Russia)
Diffractive Vector Meson Production in k_t-Factorization Approach
5 pages, 2 eps figures, talk given at X International Workshop on Deep Inelastic Scattering (DIS2002) Cracow, Poland, 30 April - 4 May 2002
Acta Phys.Polon. B33 (2002) 3517-3522
null
null
hep-ph
null
We describe the current status of the diffractive vector meson production calculations within the k_t-factorization approach. Since the amplitude of the vector meson production off a proton is expressed via the differential gluon structure function (DGSF), we take a closer look at the latter and present results of our new improved determination of the DGSF from the structure function F_2p. Having determined the differential glue, we proceed to the k_t-factorization results for the production of various vector mesons. We argue that the properties of the vector meson production can reveal the internal spin-angular and radial structure of the vector meson.
[ { "created": "Fri, 28 Jun 2002 08:08:47 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ivanov", "I. P.", "", "1 and 2" ], [ "Nikolaev", "N. N.", "", "1 and 3" ] ]
We describe the current status of the diffractive vector meson production calculations within the k_t-factorization approach. Since the amplitude of the vector meson production off a proton is expressed via the differential gluon structure function (DGSF), we take a closer look at the latter and present results of our new improved determination of the DGSF from the structure function F_2p. Having determined the differential glue, we proceed to the k_t-factorization results for the production of various vector mesons. We argue that the properties of the vector meson production can reveal the internal spin-angular and radial structure of the vector meson.
1609.08884
Chowdhury Aminul Islam
Chowdhury Aminul Islam
Study of hot and dense nuclear matter in effective QCD model
PhD thesis, 160 pages, based on arXiv:1208.3146, arXiv:1411.6407 and arXiv:1508.04061, Homi Bhabha National Institute, Successfully defended
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this thesis we use various effective QCD models to investigate hot and dense nuclear matter created in heavy ion collisions. To characterize such matter, we mainly exploit correlation functions and some of the associated spectral properties. We explore the vector meson current-current correlation function with and without the influence of vector interaction in Nambu\textendash Jona-Lasinio (NJL) model and also in its Polyakov loop extended version (PNJL). As a spectral property we have computed the dilepton rate which is found to be enhanced in strongly interacting QGP (sQGP) as compared to the Born rate in a weakly coupled QGP. We further consider the idea of entanglement between the chiral and confinement dynamics through the entangled PNJL (EPNJL) model and re-explore the vector spectral function and the spectral property such as the dilepton production rate studied in our earlier effort. Because of the strong entanglement, the coupling strengths run with the temperature and chemical potential. The implications of such running on the dilepton rate have been discussed in details. The Euclidean vector correlator and the response of the conserved density fluctuations related with the temporal vector correlator have also been investigated. We have considered both the scenarios, i.e. presence and absence of the vector interaction. The inclusion of the vector interaction also brings forth some intriguing issues in the fluctuation of conserved density, namely the QNS. It has been discussed in details and we try to address it using EPNJL model. We also assume the QGP to be made of a non-interacting quarks, antiquarks and gluons and construct a partition function which is restricted by the assumption of a color singlet projection to conform with the $SU(3)_c$ symmetry. This type of simple quantum statistical description exhibits very interesting features, which we have discussed in details.
[ { "created": "Wed, 28 Sep 2016 12:31:46 GMT", "version": "v1" }, { "created": "Thu, 5 Jan 2017 09:55:33 GMT", "version": "v2" } ]
2017-01-06
[ [ "Islam", "Chowdhury Aminul", "" ] ]
In this thesis we use various effective QCD models to investigate hot and dense nuclear matter created in heavy ion collisions. To characterize such matter, we mainly exploit correlation functions and some of the associated spectral properties. We explore the vector meson current-current correlation function with and without the influence of vector interaction in Nambu\textendash Jona-Lasinio (NJL) model and also in its Polyakov loop extended version (PNJL). As a spectral property we have computed the dilepton rate which is found to be enhanced in strongly interacting QGP (sQGP) as compared to the Born rate in a weakly coupled QGP. We further consider the idea of entanglement between the chiral and confinement dynamics through the entangled PNJL (EPNJL) model and re-explore the vector spectral function and the spectral property such as the dilepton production rate studied in our earlier effort. Because of the strong entanglement, the coupling strengths run with the temperature and chemical potential. The implications of such running on the dilepton rate have been discussed in details. The Euclidean vector correlator and the response of the conserved density fluctuations related with the temporal vector correlator have also been investigated. We have considered both the scenarios, i.e. presence and absence of the vector interaction. The inclusion of the vector interaction also brings forth some intriguing issues in the fluctuation of conserved density, namely the QNS. It has been discussed in details and we try to address it using EPNJL model. We also assume the QGP to be made of a non-interacting quarks, antiquarks and gluons and construct a partition function which is restricted by the assumption of a color singlet projection to conform with the $SU(3)_c$ symmetry. This type of simple quantum statistical description exhibits very interesting features, which we have discussed in details.
hep-ph/9509331
Claus Slotta
Enke Wang, Xiaofei Zhang and Ulrich Heinz
Spectral functions for composite fields and viscosity in hot scalar field theory
REVTeX, 17 pages, 5 uuencoded ps-figures
Phys.Rev.D53:5978-5981,1996
10.1103/PhysRevD.53.5978
TPR-95-16
hep-ph
null
We derive a spectral representation for the two-point Green function for arbitrary composite field operators in Thermo Field Dynamics (TFD). A simple way for calculating the spectral density within TFD is pointed out and compared with known results from the imaginary time formalism. The method is applied to hot $\phi^4$ theory. We give a compact derivation of the one-loop contribution to the shear viscosity and show that it is dominated by low-momentum plasmons.
[ { "created": "Tue, 19 Sep 1995 14:57:39 GMT", "version": "v1" } ]
2009-10-09
[ [ "Wang", "Enke", "" ], [ "Zhang", "Xiaofei", "" ], [ "Heinz", "Ulrich", "" ] ]
We derive a spectral representation for the two-point Green function for arbitrary composite field operators in Thermo Field Dynamics (TFD). A simple way for calculating the spectral density within TFD is pointed out and compared with known results from the imaginary time formalism. The method is applied to hot $\phi^4$ theory. We give a compact derivation of the one-loop contribution to the shear viscosity and show that it is dominated by low-momentum plasmons.
hep-ph/0207093
Boris Altshuler
Boris L. Altshuler
Ability to Count to Two. Opening Talk at the Third International Sakharov Conference on Physics
3 pages, LaTeX-2e
null
null
null
hep-ph
null
Third International Sakharov Conference on Physics organized by the Theoretical Physics Department of the Lebedev Institute, Russian Academy of Sciences, covered wide scope of topics: astrophysics, fusion, high field, high pressure and high density research, superstrings and dualities, brane world and quantum gravity, quantum field theory and high energy physics. This short Opening Word however exceeds the bounds of physics - it is about three "dynamical characteristics" of Sakharov's methodology and way of thinking: "Artseulov method", "a permanent feeling of possible personal error", and ability "to count to two", which in present days is not less demanded than before.
[ { "created": "Fri, 5 Jul 2002 18:33:34 GMT", "version": "v1" } ]
2007-05-23
[ [ "Altshuler", "Boris L.", "" ] ]
Third International Sakharov Conference on Physics organized by the Theoretical Physics Department of the Lebedev Institute, Russian Academy of Sciences, covered wide scope of topics: astrophysics, fusion, high field, high pressure and high density research, superstrings and dualities, brane world and quantum gravity, quantum field theory and high energy physics. This short Opening Word however exceeds the bounds of physics - it is about three "dynamical characteristics" of Sakharov's methodology and way of thinking: "Artseulov method", "a permanent feeling of possible personal error", and ability "to count to two", which in present days is not less demanded than before.
2111.02157
Xuan Chen
X. Chen, T. Gehrmann, E.W.N. Glover, A. Huss
Fiducial cross sections for the lepton-pair-plus-photon decay mode in Higgs production up to NNLO QCD
14 pages, 5 figures
JHEP 01 (2022) 053
10.1007/JHEP01(2022)053
ZU-TH 52/21, KA-TP-23-2021, IPPP/21/42, P3H-21-078, CERN-TH-2021-165
hep-ph
http://creativecommons.org/licenses/by/4.0/
The rare three-body decay of a Higgs boson to a lepton-antilepton pair and a photon is starting to become experimentally accessible at the LHC. We investigate how higher-order QCD corrections to the dominant gluon-fusion production process impact on the fiducial cross sections in this specific Higgs decay mode for electrons and muons. Corrections up to NNLO QCD are found to be sizeable. They are generally uniform in kinematical variables related to the Higgs boson, but display several distinctive features in the kinematics of its individual decay products.
[ { "created": "Wed, 3 Nov 2021 11:57:13 GMT", "version": "v1" } ]
2022-01-26
[ [ "Chen", "X.", "" ], [ "Gehrmann", "T.", "" ], [ "Glover", "E. W. N.", "" ], [ "Huss", "A.", "" ] ]
The rare three-body decay of a Higgs boson to a lepton-antilepton pair and a photon is starting to become experimentally accessible at the LHC. We investigate how higher-order QCD corrections to the dominant gluon-fusion production process impact on the fiducial cross sections in this specific Higgs decay mode for electrons and muons. Corrections up to NNLO QCD are found to be sizeable. They are generally uniform in kinematical variables related to the Higgs boson, but display several distinctive features in the kinematics of its individual decay products.
0706.2533
Dr. Rukmani Mohanta
A.K.Giri, B.Mawlong, R. Mohanta
Weak phase information from the color suppressed B_d^0 -> D^{*0} K^{*0} modes
11 pages, revised extensively, version to appear in Phys. Rev. D
Phys.Rev.D76:093008,2007
10.1103/PhysRevD.76.093008
null
hep-ph
null
The decay channels $B_d^0 \to D^{*0} K^{*0}$ are investigated for extracting weak $CKM$ phase information. These channels are described by color-suppressed tree diagrams only and are free from penguin contributions. The branching ratios for these channels are found to be $\sim \cal O $ $(10^{-5} - 10^{-6})$ which can be measured at the currently running $B$ factories. The method presented here may be well-suited to determine the phase $\gamma$.
[ { "created": "Mon, 18 Jun 2007 06:17:44 GMT", "version": "v1" }, { "created": "Mon, 22 Oct 2007 03:49:08 GMT", "version": "v2" } ]
2008-11-26
[ [ "Giri", "A. K.", "" ], [ "Mawlong", "B.", "" ], [ "Mohanta", "R.", "" ] ]
The decay channels $B_d^0 \to D^{*0} K^{*0}$ are investigated for extracting weak $CKM$ phase information. These channels are described by color-suppressed tree diagrams only and are free from penguin contributions. The branching ratios for these channels are found to be $\sim \cal O $ $(10^{-5} - 10^{-6})$ which can be measured at the currently running $B$ factories. The method presented here may be well-suited to determine the phase $\gamma$.
hep-ph/9902427
Walter Grimus
R.A. Bertlmann, W. Grimus and B.C. Hiesmayr
Quantum mechanics, Furry's hypothesis and a measure of decoherence in the K^0 \bar{K}^0 system
12 pages, 1 figure, revtex
Phys.Rev. D60 (1999) 114032
10.1103/PhysRevD.60.114032
UWThPh-1999-9
hep-ph quant-ph
null
We consider strangeness correlations of the EPR type in K^0 \bar{K}^0 pairs created in a J^{PC} = 1^{--} state as a function of time under the hypothesis that spontaneous decoherence takes place. We parameterize the degree of decoherence by a factor (1-\zeta) which multiplies the quantum-mechanical interference terms occurring in the amplitudes for like and unlike strangeness events and discuss the dependence of this procedure on the basis chosen in the K^0--\bar{K}^0 space to which the interference terms correspond. Consequently, all statements about the ``decoherence parameter'' \zeta inferred from experimental data are basis-dependent as well. We illustrate this point by estimating the value of \zeta for the two bases {K_L, K_S} and {K^0, \bar{K}^0} with the help of recent data of the CPLEAR experiment.
[ { "created": "Mon, 22 Feb 1999 17:00:29 GMT", "version": "v1" } ]
2009-10-31
[ [ "Bertlmann", "R. A.", "" ], [ "Grimus", "W.", "" ], [ "Hiesmayr", "B. C.", "" ] ]
We consider strangeness correlations of the EPR type in K^0 \bar{K}^0 pairs created in a J^{PC} = 1^{--} state as a function of time under the hypothesis that spontaneous decoherence takes place. We parameterize the degree of decoherence by a factor (1-\zeta) which multiplies the quantum-mechanical interference terms occurring in the amplitudes for like and unlike strangeness events and discuss the dependence of this procedure on the basis chosen in the K^0--\bar{K}^0 space to which the interference terms correspond. Consequently, all statements about the ``decoherence parameter'' \zeta inferred from experimental data are basis-dependent as well. We illustrate this point by estimating the value of \zeta for the two bases {K_L, K_S} and {K^0, \bar{K}^0} with the help of recent data of the CPLEAR experiment.
0806.4950
Makiko Nagashima
Makiko Nagashima
U-spin Implication for B_s Physics and New Physics
4 pages, Prepared for the proceedings of the Flavor Physics and CP Violation Conference, Taipei, 2008
null
null
UdeM-GPP-TH-08-169
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With U-spin symmetry, b->s and b->d penguin decays could be a subtle probe of CP violating new physics contributions. We show that, for B->PP (P stands for a pseudoscalar meson), the U-spin relation is expected to be violated for only one decay pair by assuming that new physics affects only b->s transition processes. We also very shortly discuss the polarizations of two types of U-spin pairs for B->VV (V stands for a vector meson).
[ { "created": "Mon, 30 Jun 2008 18:21:28 GMT", "version": "v1" } ]
2008-07-01
[ [ "Nagashima", "Makiko", "" ] ]
With U-spin symmetry, b->s and b->d penguin decays could be a subtle probe of CP violating new physics contributions. We show that, for B->PP (P stands for a pseudoscalar meson), the U-spin relation is expected to be violated for only one decay pair by assuming that new physics affects only b->s transition processes. We also very shortly discuss the polarizations of two types of U-spin pairs for B->VV (V stands for a vector meson).
hep-ph/0403161
Shahin Agaev
S.S.Agaev
Power corrections to the $\pi^0\gamma$ transition form factor and pion distribution amplitudes
23 pages, 6 figures; the version published in Phys. Rev. D69, 094010 (2004)
Phys.Rev. D69 (2004) 094010
10.1103/PhysRevD.69.094010
null
hep-ph
null
Employing the standard hard-scattering approach and the running coupling method we calculate a class of power-suppressed corrections $\sim 1/Q^{2n},n=1,2,3,...$ to the electromagnetic $\pi^0\gamma$ transition form factor (FF) $Q^2F_{\pi\gamma}(Q^2)$ arising from the end-point $x \to 0,1$ integration regions. In the investigations we use a hard-scattering amplitude of the subprocess $\gamma+\gamma^{*} \to q +\bar{q}$, symmetrized under exchange $\mu_R^2 \leftrightarrow \bar{\mu}_R^2$ important for exclusive processes containing two external photons. In the computations the pion model distribution amplitudes (DA's) with one and two non-asymptotic terms are employed. The obtained predictions are compared with the CLEO data and constraints on the DA parameters $b_2(\mu_0^2)$ and $b_4(\mu_0^2)$ at the normalization point $\mu_0^2=1 GeV^2$ are extracted. Further restrictions on the pion DA's are deduced from the experimental data on the electromagnetic FF $F_{\pi}(Q^2)$.
[ { "created": "Mon, 15 Mar 2004 13:22:19 GMT", "version": "v1" }, { "created": "Tue, 16 Mar 2004 16:47:19 GMT", "version": "v2" }, { "created": "Wed, 26 May 2004 12:21:07 GMT", "version": "v3" } ]
2009-11-10
[ [ "Agaev", "S. S.", "" ] ]
Employing the standard hard-scattering approach and the running coupling method we calculate a class of power-suppressed corrections $\sim 1/Q^{2n},n=1,2,3,...$ to the electromagnetic $\pi^0\gamma$ transition form factor (FF) $Q^2F_{\pi\gamma}(Q^2)$ arising from the end-point $x \to 0,1$ integration regions. In the investigations we use a hard-scattering amplitude of the subprocess $\gamma+\gamma^{*} \to q +\bar{q}$, symmetrized under exchange $\mu_R^2 \leftrightarrow \bar{\mu}_R^2$ important for exclusive processes containing two external photons. In the computations the pion model distribution amplitudes (DA's) with one and two non-asymptotic terms are employed. The obtained predictions are compared with the CLEO data and constraints on the DA parameters $b_2(\mu_0^2)$ and $b_4(\mu_0^2)$ at the normalization point $\mu_0^2=1 GeV^2$ are extracted. Further restrictions on the pion DA's are deduced from the experimental data on the electromagnetic FF $F_{\pi}(Q^2)$.
1206.7108
Igor Ivanov
I. P. Ivanov, E. Vdovin
Discrete symmetries in the three-Higgs-doublet model
5 pages; v2: expanded introduction, some minor corrections, matches the published version
Phys. Rev. D 86, 095030 (2012)
10.1103/PhysRevD.86.095030
null
hep-ph math.GR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
N-Higgs-doublet models (NHDM) are among the most popular examples of electroweak symmetry breaking mechanisms beyond the Standard Model. Discrete symmetries imposed on the NHDM scalar potential play a pivotal role in shaping the phenomenology of the model, and various symmetry groups have been studied so far. However, in spite of all efforts, the classification of finite Higgs-family symmetry groups realizable in NHDM for any N>2 is still missing. Here, we solve this problem for the three-Higgs-doublet model by making use of Burnside's theorem and other results from pure finite group theory which are rarely exploited in physics. Our method and results can be also used beyond high-energy physics, for example, in study of possible symmetries in three-band superconductors.
[ { "created": "Fri, 29 Jun 2012 19:19:29 GMT", "version": "v1" }, { "created": "Wed, 28 Nov 2012 23:00:38 GMT", "version": "v2" } ]
2012-11-30
[ [ "Ivanov", "I. P.", "" ], [ "Vdovin", "E.", "" ] ]
N-Higgs-doublet models (NHDM) are among the most popular examples of electroweak symmetry breaking mechanisms beyond the Standard Model. Discrete symmetries imposed on the NHDM scalar potential play a pivotal role in shaping the phenomenology of the model, and various symmetry groups have been studied so far. However, in spite of all efforts, the classification of finite Higgs-family symmetry groups realizable in NHDM for any N>2 is still missing. Here, we solve this problem for the three-Higgs-doublet model by making use of Burnside's theorem and other results from pure finite group theory which are rarely exploited in physics. Our method and results can be also used beyond high-energy physics, for example, in study of possible symmetries in three-band superconductors.
1510.02154
Tomasz Krajewski
Tomasz Krajewski and Zygmunt Lalak
Naturalness of effective theories in Wilsonian approach
12 pages, 6 figures, proceeding of a talk given at "18th International Conference From the Planck Scale to the Electroweak Scale" held in Ioannina, Greece, 25-29 May 2015
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have computed Wilsonian effective action in a simple model containing scalar field with quartic self-coupling which interacts via Yukawa coupling with a Dirac fermion. The model is invariant under a chiral parity operation, which can be spontaneously broken by a vev of the scalar field. We have computed explicitly Wilsonian running of relevant parameters which makes it possible to discuss in a consistent manner the issue of fine-tuning and stability of the scalar potential. This has been compared with the typical picture based on Gell-Mann-Low running. Since Wilsonian running includes automatically integration out of heavy degrees of freedom, the running differs markedly from the Gell-Mann-Low version. However, similar behavior can be observed: scalar mass squared parameter and the quartic coupling can change sign from a positive to a negative one due to running which causes spontaneous symmetry breaking or an instability in the renormalizable part of the potential for a given range of scales. As for the issue of fine-tuning, since in the Wilsonian approach power-law terms are not subtracted, one can clearly observe the quadratic sensitivity of fine-tuning measure to the change of the cut-off scale.
[ { "created": "Wed, 7 Oct 2015 22:12:58 GMT", "version": "v1" } ]
2015-10-09
[ [ "Krajewski", "Tomasz", "" ], [ "Lalak", "Zygmunt", "" ] ]
We have computed Wilsonian effective action in a simple model containing scalar field with quartic self-coupling which interacts via Yukawa coupling with a Dirac fermion. The model is invariant under a chiral parity operation, which can be spontaneously broken by a vev of the scalar field. We have computed explicitly Wilsonian running of relevant parameters which makes it possible to discuss in a consistent manner the issue of fine-tuning and stability of the scalar potential. This has been compared with the typical picture based on Gell-Mann-Low running. Since Wilsonian running includes automatically integration out of heavy degrees of freedom, the running differs markedly from the Gell-Mann-Low version. However, similar behavior can be observed: scalar mass squared parameter and the quartic coupling can change sign from a positive to a negative one due to running which causes spontaneous symmetry breaking or an instability in the renormalizable part of the potential for a given range of scales. As for the issue of fine-tuning, since in the Wilsonian approach power-law terms are not subtracted, one can clearly observe the quadratic sensitivity of fine-tuning measure to the change of the cut-off scale.
1603.08748
Yubing Dong
Yubing Dong, Fei Huang, Pengnian Shen, and Zongye Zhang
Decay width of $d^*(2380)\to NN \pi\pi$ processes
6 pages, 1 figure, 1 table
Phys. Rev. C 94, 014003 (2016)
10.1103/PhysRevC.94.014003
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The decay widths of four-body double-pion decays $\ds\to pn \pi^0\pi^0$, $\ds\to pn \pi^+\pi^-$, and iso-scalar parts of $\ds\to pp \pi^0\pi^-$ and $\ds\to nn \pi^+\pi^0$ are explicitly calculated with the help of the $d^*$ wave function obtained in a chiral SU(3) quark model calculation. The effect of the dynamical structure on $\ds$'s width is analyzed both in the single $\Delta\Delta$ channel and coupled $\Delta\Delta$ and $CC$ channel approximations. It is found that in the coupled-channel approximation, the obtained partial decay widths of $\ds\to pn \pi^0\pi^0$, $\ds\to pn \pi^+\pi^-$, and those of $d^*$ to the iso-scalar parts of $pp \pi^0\pi^-$ and $nn \pi^+\pi^0$ are about $7.4$MeV, $16.4$MeV, $3.5$MeV and $3.5$MeV, respectively As a consequence, the total width is about $64.5$MeV. These widths are consistent with those estimated by using the corresponding cross section data in our previous investigation and also the observed data. But in the single $\Delta\Delta$ channel approximation, the widths are still almost 2-times larger than the measured values. Apparently, the explicitly calculated width together with the evaluated mass of $d^*$ in the coupled $\Delta\Delta$ and $CC$ channel approximation can well explain the observed data, which again supports our assertion that the $\ds$ resonance is a six-quark dominated exotic state.
[ { "created": "Tue, 29 Mar 2016 12:44:08 GMT", "version": "v1" } ]
2016-07-27
[ [ "Dong", "Yubing", "" ], [ "Huang", "Fei", "" ], [ "Shen", "Pengnian", "" ], [ "Zhang", "Zongye", "" ] ]
The decay widths of four-body double-pion decays $\ds\to pn \pi^0\pi^0$, $\ds\to pn \pi^+\pi^-$, and iso-scalar parts of $\ds\to pp \pi^0\pi^-$ and $\ds\to nn \pi^+\pi^0$ are explicitly calculated with the help of the $d^*$ wave function obtained in a chiral SU(3) quark model calculation. The effect of the dynamical structure on $\ds$'s width is analyzed both in the single $\Delta\Delta$ channel and coupled $\Delta\Delta$ and $CC$ channel approximations. It is found that in the coupled-channel approximation, the obtained partial decay widths of $\ds\to pn \pi^0\pi^0$, $\ds\to pn \pi^+\pi^-$, and those of $d^*$ to the iso-scalar parts of $pp \pi^0\pi^-$ and $nn \pi^+\pi^0$ are about $7.4$MeV, $16.4$MeV, $3.5$MeV and $3.5$MeV, respectively As a consequence, the total width is about $64.5$MeV. These widths are consistent with those estimated by using the corresponding cross section data in our previous investigation and also the observed data. But in the single $\Delta\Delta$ channel approximation, the widths are still almost 2-times larger than the measured values. Apparently, the explicitly calculated width together with the evaluated mass of $d^*$ in the coupled $\Delta\Delta$ and $CC$ channel approximation can well explain the observed data, which again supports our assertion that the $\ds$ resonance is a six-quark dominated exotic state.
hep-ph/0404223
Abel Miranda Dr
A. Miranda
Modelling the light quark vacuum
11 pages, no figures
null
null
null
hep-ph
null
The triumphs of the Standard Model of Particle Physics call attention upon an old idea, that the so-called vacuum is an accessible physical medium, and not just a tautology. I take this idea as a serious working hypothesis, and I suggest a new way of trying to define and understand the structure of the light quark vacuum within the general framework of the Standard Model.
[ { "created": "Sun, 25 Apr 2004 19:30:44 GMT", "version": "v1" } ]
2016-09-06
[ [ "Miranda", "A.", "" ] ]
The triumphs of the Standard Model of Particle Physics call attention upon an old idea, that the so-called vacuum is an accessible physical medium, and not just a tautology. I take this idea as a serious working hypothesis, and I suggest a new way of trying to define and understand the structure of the light quark vacuum within the general framework of the Standard Model.
hep-ph/0411383
David Blaschke
D.B. Blaschke, A.V. Prozorkevich, S.A. Smolyansky
Vacuum creation of massive vector bosons and its application to a conformal cosmological model
13 pages, 3 figures, references added
null
null
null
hep-ph
null
In the simple model of a massive vector field in flat space-time, we derive a kinetic equation of non-Markovian type, describing the vacuum pair creation under the action of external fields of different nature. We use for this aim the non-perturbative methods of kinetic theory in combination with a new element when the transition of the instantaneous quasiparticle representation is realized within the oscillator (holomorphic) representation. We study in detail the process of vacuum creation of vector bosons generated by a time-dependent boson mass in accordance with a conformal-invariant scalar-tensor gravitational theory and its cosmological application. It is indicated that the choice of the equation of state (EoS) of the Universe allows to obtain a number density of the vector bosons that is sufficient to explain the observed number density of photons in the cosmic microwave background radiation. It is shown that the vector boson gas created from the vacuum is in a strong non-equilibrium state and corresponds to a cold dust-like EoS.
[ { "created": "Tue, 30 Nov 2004 01:05:46 GMT", "version": "v1" }, { "created": "Wed, 1 Dec 2004 22:59:44 GMT", "version": "v2" } ]
2007-05-23
[ [ "Blaschke", "D. B.", "" ], [ "Prozorkevich", "A. V.", "" ], [ "Smolyansky", "S. A.", "" ] ]
In the simple model of a massive vector field in flat space-time, we derive a kinetic equation of non-Markovian type, describing the vacuum pair creation under the action of external fields of different nature. We use for this aim the non-perturbative methods of kinetic theory in combination with a new element when the transition of the instantaneous quasiparticle representation is realized within the oscillator (holomorphic) representation. We study in detail the process of vacuum creation of vector bosons generated by a time-dependent boson mass in accordance with a conformal-invariant scalar-tensor gravitational theory and its cosmological application. It is indicated that the choice of the equation of state (EoS) of the Universe allows to obtain a number density of the vector bosons that is sufficient to explain the observed number density of photons in the cosmic microwave background radiation. It is shown that the vector boson gas created from the vacuum is in a strong non-equilibrium state and corresponds to a cold dust-like EoS.
1411.1641
Fredy Ochoa
R. Martinez, J. Nisperuza, F. Ochoa, J. P. Rubio, C.F. Sierra
Scalar coupling limits and diphoton Higgs decay from LHC in an $U(1)'$ model with scalar dark matter
Additional figures and analysis in new version
Phys. Rev. D 92, 035016 (2015)
10.1103/PhysRevD.92.035016
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the context of an nonuniversal $U(1)'$ extension of the standard model free from anomalies, we introduce a complex scalar singlet candidate to be dark matter. In addition, an extra scalar doublet and a heavy scalar singlet are required to provide masses to all fermions and to break spontaneously the symmetries. From unitarity and stability of the Higgs potential, we find the full set of bounds and order relations for the scalar coupling constants. Using recent data from the CERN-LHC collider, we study the signal strenght of the diphoton Higgs decay $R_{\gamma \gamma}$, which imposes very stringent bounds to the scalar couplings and other scalar parameters. We obtain constraints in different scenarios of the space of parameters, where decays into dark matter may or may not contribute according to the mass of the scalar dark matter candidate. By assuming that the lightest scalar boson of the model corresponds to the observed Higgs boson, we evaluate deviations from the SM of the trilineal Higgs self-coupling. The conditions from unitarity, stability and Higgs diphoton decay data allow trilineal deviations in the range $0 \leq \delta g \lesssim -72\%$.
[ { "created": "Thu, 6 Nov 2014 15:45:02 GMT", "version": "v1" }, { "created": "Wed, 14 Jan 2015 17:05:40 GMT", "version": "v2" }, { "created": "Thu, 27 Aug 2015 03:57:00 GMT", "version": "v3" } ]
2015-08-28
[ [ "Martinez", "R.", "" ], [ "Nisperuza", "J.", "" ], [ "Ochoa", "F.", "" ], [ "Rubio", "J. P.", "" ], [ "Sierra", "C. F.", "" ] ]
In the context of an nonuniversal $U(1)'$ extension of the standard model free from anomalies, we introduce a complex scalar singlet candidate to be dark matter. In addition, an extra scalar doublet and a heavy scalar singlet are required to provide masses to all fermions and to break spontaneously the symmetries. From unitarity and stability of the Higgs potential, we find the full set of bounds and order relations for the scalar coupling constants. Using recent data from the CERN-LHC collider, we study the signal strenght of the diphoton Higgs decay $R_{\gamma \gamma}$, which imposes very stringent bounds to the scalar couplings and other scalar parameters. We obtain constraints in different scenarios of the space of parameters, where decays into dark matter may or may not contribute according to the mass of the scalar dark matter candidate. By assuming that the lightest scalar boson of the model corresponds to the observed Higgs boson, we evaluate deviations from the SM of the trilineal Higgs self-coupling. The conditions from unitarity, stability and Higgs diphoton decay data allow trilineal deviations in the range $0 \leq \delta g \lesssim -72\%$.
0811.3675
Marco Guzzi
Claudio Coriano', Marco Guzzi, Antonio Mariano and Simone Morelli
A Light Supersymmetric Axion in an Anomalous Abelian Extension of the Standard Model
46 pages, 28 figures. Revised version, accepted for a publication on Phys.Rev.D
Phys.Rev.D80:035006,2009
10.1103/PhysRevD.80.035006
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a supersymmetric extension of the Standard Model (USSM-A) with an anomalous U(1) and Stueckelberg axions for anomaly cancellation, generalizing similar non-supersymmetric constructions. The model, built by a bottom-up approach, is expected to capture the low-energy supersymmetric description of axionic symmetries in theories with gauged anomalous abelian interactions, previously explored in the non-supersymmetric case for scenarios with intersecting branes. The choice of a USSM-like superpotential, with one extra singlet superfield and an extra abelian symmetry, allows a physical axion-like particle in the spectrum. We describe some general features of this construction and in particular the modification of the dark-matter sector which involves both the axion and several neutralinos with an axino component. The axion is expected to be very light in the absence of phases in the superpotential but could acquire a mass which can also be in the few GeV range or larger. In particular, the gauging of the anomalous symmetry allows independent mass/coupling interaction to the gauge fields of this particle, a feature which is absent in traditional (invisible) axion models. We comment on the general implications of our study for the signature of moduli from string theory due to the presence of these anomalous symmetries.
[ { "created": "Sun, 23 Nov 2008 08:23:15 GMT", "version": "v1" }, { "created": "Wed, 15 Jul 2009 15:08:26 GMT", "version": "v2" } ]
2009-08-13
[ [ "Coriano'", "Claudio", "" ], [ "Guzzi", "Marco", "" ], [ "Mariano", "Antonio", "" ], [ "Morelli", "Simone", "" ] ]
We present a supersymmetric extension of the Standard Model (USSM-A) with an anomalous U(1) and Stueckelberg axions for anomaly cancellation, generalizing similar non-supersymmetric constructions. The model, built by a bottom-up approach, is expected to capture the low-energy supersymmetric description of axionic symmetries in theories with gauged anomalous abelian interactions, previously explored in the non-supersymmetric case for scenarios with intersecting branes. The choice of a USSM-like superpotential, with one extra singlet superfield and an extra abelian symmetry, allows a physical axion-like particle in the spectrum. We describe some general features of this construction and in particular the modification of the dark-matter sector which involves both the axion and several neutralinos with an axino component. The axion is expected to be very light in the absence of phases in the superpotential but could acquire a mass which can also be in the few GeV range or larger. In particular, the gauging of the anomalous symmetry allows independent mass/coupling interaction to the gauge fields of this particle, a feature which is absent in traditional (invisible) axion models. We comment on the general implications of our study for the signature of moduli from string theory due to the presence of these anomalous symmetries.
2212.00467
Mathieu Pellen
Micha{\l} Czakon, Alexander Mitov, Mathieu Pellen, Rene Poncelet
A detailed investigation of W+c-jet at the LHC
23 pages, 31 pdf Figures. Matches published version
JHEP 02 (2023) 241
10.1007/JHEP02(2023)241
CAVENDISH--HEP--22/09, FR-PHENO-2022-09, P3H-22-117, TTK-22-41
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
State-of-the-art analyses of W+c-jet production at the LHC require precise predictions. In the present work, we study in detail the impact of off-diagonal CKM elements up to next-to-next-to leading order in QCD, the influence of flavored jet algorithms, and the size of electroweak corrections. In addition, we also investigate phenomenological aspects related to the exact definition of the process. We find that all these effects can be of the order of several per cent for both the fiducial cross section and differential distributions. They are, therefore, very relevant for the interpretation of current and upcoming measurements.
[ { "created": "Thu, 1 Dec 2022 12:46:02 GMT", "version": "v1" }, { "created": "Fri, 16 Dec 2022 13:14:18 GMT", "version": "v2" }, { "created": "Wed, 1 Mar 2023 08:56:38 GMT", "version": "v3" } ]
2023-03-02
[ [ "Czakon", "Michał", "" ], [ "Mitov", "Alexander", "" ], [ "Pellen", "Mathieu", "" ], [ "Poncelet", "Rene", "" ] ]
State-of-the-art analyses of W+c-jet production at the LHC require precise predictions. In the present work, we study in detail the impact of off-diagonal CKM elements up to next-to-next-to leading order in QCD, the influence of flavored jet algorithms, and the size of electroweak corrections. In addition, we also investigate phenomenological aspects related to the exact definition of the process. We find that all these effects can be of the order of several per cent for both the fiducial cross section and differential distributions. They are, therefore, very relevant for the interpretation of current and upcoming measurements.
1203.1573
John W. Moffat
J. W. Moffat
Theory of Electroweak Gauge Interactions
14 pages, 4 figures, changes to text and typos corrected. arXiv admin note: text overlap with arXiv:0812.1991
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The conditions obtained by Salam for a general gauge theory to be renormalizable are derived. They require that in a gauge invariant formalism the bare boson mass associated with the massive non-Abelian vector field is zero. A solution to the origin of masses in electroweak theory is proposed in which the physical masses of the $W$ and $Z$ bosons and the quarks and leptons are derived from their self-energies according to a self-consistent scheme.
[ { "created": "Wed, 7 Mar 2012 19:24:14 GMT", "version": "v1" }, { "created": "Mon, 19 Mar 2012 18:54:45 GMT", "version": "v2" } ]
2012-03-20
[ [ "Moffat", "J. W.", "" ] ]
The conditions obtained by Salam for a general gauge theory to be renormalizable are derived. They require that in a gauge invariant formalism the bare boson mass associated with the massive non-Abelian vector field is zero. A solution to the origin of masses in electroweak theory is proposed in which the physical masses of the $W$ and $Z$ bosons and the quarks and leptons are derived from their self-energies according to a self-consistent scheme.
hep-ph/9611339
Pierre Sikivie
Pierre Sikivie (U of Florida)
Dark matter axions '96
12 pages, 2 figures, Latex, invited talk at the APCTP Inauguration Conference in Seoul, Korea, June 4-10, 1996 and at the Workshop on Aspects of Dark Matter in Astro- and Particle Physics in Heidelberg, Germany, Sept. 16-20, 1996
null
null
UFIFT-HET-96-24
hep-ph astro-ph
null
Contents: 1. The strong CP problem 2. Dark matter axions 3. The cavity detector of galactic halo axions 4. The phase space structure of cold dark matter halos
[ { "created": "Fri, 15 Nov 1996 16:19:04 GMT", "version": "v1" } ]
2007-05-23
[ [ "Sikivie", "Pierre", "", "U of Florida" ] ]
Contents: 1. The strong CP problem 2. Dark matter axions 3. The cavity detector of galactic halo axions 4. The phase space structure of cold dark matter halos
1107.1997
Arghya Choudhury
Nabanita Bhattacharyya, Arghya Choudhury, Amitava Datta
Low mass neutralino dark matter in mSUGRA and more general models in the light of LHC data
33 pages, 2 figures, analyses updated for 1 fb^{-1} of LHC data and presented in a new section, some new references have been added, published in Phys. Rev. D
Phys. Rev. D 84, 095006 (2011)
10.1103/PhysRevD.84.095006
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $b\tau j \etslash$ signal at the ongoing LHC experiments is simulated with Pythia in the mSUGRA and other models of SUSY breaking. Special attention is given on the compatibility of this signature with the low mass neutralino dark matter (LMNDM) scenario consistent with WMAP data. In the mSUGRA model the above signal as well as the LMNDM scenario are strongly disfavoured due to the constraints from the on going SUSY searches at the LHC. This tension, however, originates from the model dependent correlations among the parameters in the strong and electroweak sectors of mSUGRA. That there is no serious conflict between the LMNDM scenario and the LHC data is demonstrated by constructing generic phenomenological models such that the strong sector is unconstrained or mildly constrained by the existing LHC data and parameters in the electroweak sector, unrelated to the strong sector,yield DM relic density consistent with the WMAP data. The proposed models, fairly insensitive to the conventional SUSY searches in the jets + $\etslash$ and other channels, yield observable signal in the suggested channel for $\lum \gsim 1 \ifb$ of data. They are also consistent with the LMNDM scenario and can be tested by the direct dark matter search experiments in the near future. Some of these models can be realized by non-universal scalar and gaugino masses at the GUT scale.
[ { "created": "Mon, 11 Jul 2011 11:16:50 GMT", "version": "v1" }, { "created": "Mon, 18 Jul 2011 09:53:14 GMT", "version": "v2" }, { "created": "Wed, 27 Jul 2011 12:31:15 GMT", "version": "v3" }, { "created": "Wed, 12 Oct 2011 13:41:53 GMT", "version": "v4" }, { "created": "Wed, 9 Nov 2011 12:33:57 GMT", "version": "v5" } ]
2011-11-10
[ [ "Bhattacharyya", "Nabanita", "" ], [ "Choudhury", "Arghya", "" ], [ "Datta", "Amitava", "" ] ]
The $b\tau j \etslash$ signal at the ongoing LHC experiments is simulated with Pythia in the mSUGRA and other models of SUSY breaking. Special attention is given on the compatibility of this signature with the low mass neutralino dark matter (LMNDM) scenario consistent with WMAP data. In the mSUGRA model the above signal as well as the LMNDM scenario are strongly disfavoured due to the constraints from the on going SUSY searches at the LHC. This tension, however, originates from the model dependent correlations among the parameters in the strong and electroweak sectors of mSUGRA. That there is no serious conflict between the LMNDM scenario and the LHC data is demonstrated by constructing generic phenomenological models such that the strong sector is unconstrained or mildly constrained by the existing LHC data and parameters in the electroweak sector, unrelated to the strong sector,yield DM relic density consistent with the WMAP data. The proposed models, fairly insensitive to the conventional SUSY searches in the jets + $\etslash$ and other channels, yield observable signal in the suggested channel for $\lum \gsim 1 \ifb$ of data. They are also consistent with the LMNDM scenario and can be tested by the direct dark matter search experiments in the near future. Some of these models can be realized by non-universal scalar and gaugino masses at the GUT scale.
hep-ph/9908528
Victor Goncalves
M. B. Gay Ducati, V. P. Gon\c{c}alves (IF-UFRGS)
The AGL Equation from the Dipole Picture
16 pages, 2 figures. Accepted for publication in Nuc. Phys. B
Nucl.Phys. B557 (1999) 296-306
null
null
hep-ph
null
The AGL equation includes all multiple pomeron exchanges in the double logarithmic approximation (DLA) limit, leading to an unitarized gluon distribution in the small x regime. This equation was originally obtained using the Glauber-Mueller approach. We demonstrate in this paper that the AGL equation and, consequently, the GLR equation, can also be obtained from the dipole picture in the double logarithmic limit, using an evolution equation, recently proposed, which includes all multiple pomeron exchanges in the leading logarithmic approximation. Our conclusion is that the AGL equation is a good candidate for an unitarized evolution equation at small x in the DLA limit.
[ { "created": "Tue, 31 Aug 1999 19:39:57 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ducati", "M. B. Gay", "", "IF-UFRGS" ], [ "Gonçalves", "V. P.", "", "IF-UFRGS" ] ]
The AGL equation includes all multiple pomeron exchanges in the double logarithmic approximation (DLA) limit, leading to an unitarized gluon distribution in the small x regime. This equation was originally obtained using the Glauber-Mueller approach. We demonstrate in this paper that the AGL equation and, consequently, the GLR equation, can also be obtained from the dipole picture in the double logarithmic limit, using an evolution equation, recently proposed, which includes all multiple pomeron exchanges in the leading logarithmic approximation. Our conclusion is that the AGL equation is a good candidate for an unitarized evolution equation at small x in the DLA limit.
2102.05619
Chang-Yuan Yao
Ning Chen, Bin Wang, Chang-Yuan Yao
The collider tests of a leptophilic scalar for the anomalous magnetic moments
minor corrections with references added, 17 pages, 9 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study the anomalous muon and electron magnetic moments by introducing a scalar with CP-violating Yukawa couplings to the lepton sector. By fitting these two magnetic moments with the recent experimental measurements, we find that such a leptophilic scalar in the mass range of $\mathcal{O}(10)- \mathcal{O}(1000 )\,\rm GeV$ can be a possible source for the current experimental deviations from the Standard Model (SM) predictions, with $\mathcal{O}(0.1) - \mathcal{O}(1)$ Yukawa couplings. The current electron and muon EDM constraints to the general CP-violating Yukawa couplings are discussed. We propose to search such a leptophilic scalar mediated at the future high-luminosity LHC (HL-LHC) runs, as well as the high-energy lepton colliders, including the CEPC and the muon collider. Our results show that the leptophilic scalar in the mass range of $\mathcal{O}(10)- \mathcal{O}(1000 )\,\rm GeV$ can be fully probed by the future experimental searches at the HL-LHC and the lepton colliders at their early stages.
[ { "created": "Wed, 10 Feb 2021 18:28:11 GMT", "version": "v1" }, { "created": "Sun, 7 Mar 2021 09:00:39 GMT", "version": "v2" } ]
2021-03-09
[ [ "Chen", "Ning", "" ], [ "Wang", "Bin", "" ], [ "Yao", "Chang-Yuan", "" ] ]
We study the anomalous muon and electron magnetic moments by introducing a scalar with CP-violating Yukawa couplings to the lepton sector. By fitting these two magnetic moments with the recent experimental measurements, we find that such a leptophilic scalar in the mass range of $\mathcal{O}(10)- \mathcal{O}(1000 )\,\rm GeV$ can be a possible source for the current experimental deviations from the Standard Model (SM) predictions, with $\mathcal{O}(0.1) - \mathcal{O}(1)$ Yukawa couplings. The current electron and muon EDM constraints to the general CP-violating Yukawa couplings are discussed. We propose to search such a leptophilic scalar mediated at the future high-luminosity LHC (HL-LHC) runs, as well as the high-energy lepton colliders, including the CEPC and the muon collider. Our results show that the leptophilic scalar in the mass range of $\mathcal{O}(10)- \mathcal{O}(1000 )\,\rm GeV$ can be fully probed by the future experimental searches at the HL-LHC and the lepton colliders at their early stages.
1703.09894
Ashutosh Alok
Khushboo Dixit, Ashutosh Kumar Alok, Subhashish Banerjee, Dinesh Kumar
Geometric phase and neutrino mass hierarchy problem
7 pages, 3 figures; Published version
J.Phys. G45 (2018) no.8, 085002
10.1088/1361-6471/aac454
null
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the geometric phase for neutrinos at various man-made facilities, such as the reactor and accelerator neutrino experiments. The analysis is done for the three flavor neutrino scenario, in the presence of matter and for general, noncyclic paths. The geometric phase is seen to be sensitive to the CP violating phase in the leptonic sector and the sign ambiguity in Delta_{31}. We find that for neutrino experimental facilities where the geometric phase can complete one cycle, all the phase curves corresponding to different values of CP violating phase, converge to a single point, called the cluster point. There are two distinct cluster points for positive and negative signs of Delta_{31}. Thus the geometric phase can contribute to our understanding of the neutrino mass hierarchy problem.
[ { "created": "Wed, 29 Mar 2017 06:08:29 GMT", "version": "v1" }, { "created": "Sun, 27 May 2018 13:15:48 GMT", "version": "v2" } ]
2018-07-10
[ [ "Dixit", "Khushboo", "" ], [ "Alok", "Ashutosh Kumar", "" ], [ "Banerjee", "Subhashish", "" ], [ "Kumar", "Dinesh", "" ] ]
We study the geometric phase for neutrinos at various man-made facilities, such as the reactor and accelerator neutrino experiments. The analysis is done for the three flavor neutrino scenario, in the presence of matter and for general, noncyclic paths. The geometric phase is seen to be sensitive to the CP violating phase in the leptonic sector and the sign ambiguity in Delta_{31}. We find that for neutrino experimental facilities where the geometric phase can complete one cycle, all the phase curves corresponding to different values of CP violating phase, converge to a single point, called the cluster point. There are two distinct cluster points for positive and negative signs of Delta_{31}. Thus the geometric phase can contribute to our understanding of the neutrino mass hierarchy problem.
hep-ph/0005253
U. Meissner
Ulf-G. Mei{\ss}ner, J.A. Oller
J/\Psi \to \phi \pi \pi (K \bar{K}) decays, chiral dynamcis and OZI violation
revtex, 21 pages, 10 figures, extended discussion of the model in section 2 and some minor corrections, version accepted for publication in Nucl. Phys. A
Nucl.Phys.A679:671-697,2001
10.1016/S0375-9474(00)00367-5
null
hep-ph nucl-th
null
We have studied the invariant mass distributions of the \pi\pi and K \bar{K} systems for invariant masses up to 1.2 GeV from the J/\Psi \to \phi \pi\pi(K\bar{K}) decays. The approach exploits the connection between these processes and the \pi\pi and K\bar{K} strange and non-strange scalar form factors by considering the \phi meson as a spectator. The calculated scalar form factors are then matched with the ones from next-to-leading order chiral perturbation theory, including the calculation of the the K\bar{K} scalar form factors. Final state interactions in the J/\Psi \to \phi \pi\pi (K\bar{K}) processes are taken into account as rescattering effects in the system of the two pseudoscalar mesons. A very good agreement with the experimental data from DM2 and MARK-III is achieved. Furthermore, making use of SU(3) symmetry, the S-wave contribution to the \pi^+\pi^- event distribution in the J/\Psi \to \omega \pi^+\pi^- reaction is also given and the data up to energies of about 0.7 GeV are reproduced. These decays of the J/\Psi to a vector and a pair of pseudoscalars turn out to be very sensitive to OZI violating physics which we parametrize in terms of a direct OZI violation parameter and the chiral perturbation theory low energy constants L_4^r and L_6^r. These constants all come out very different from zero, lending further credit to the statement that the OZI rule is not operative in the scalar 0^{++} channel.
[ { "created": "Thu, 25 May 2000 12:47:14 GMT", "version": "v1" }, { "created": "Thu, 14 Sep 2000 06:06:57 GMT", "version": "v2" } ]
2008-11-26
[ [ "Meißner", "Ulf-G.", "" ], [ "Oller", "J. A.", "" ] ]
We have studied the invariant mass distributions of the \pi\pi and K \bar{K} systems for invariant masses up to 1.2 GeV from the J/\Psi \to \phi \pi\pi(K\bar{K}) decays. The approach exploits the connection between these processes and the \pi\pi and K\bar{K} strange and non-strange scalar form factors by considering the \phi meson as a spectator. The calculated scalar form factors are then matched with the ones from next-to-leading order chiral perturbation theory, including the calculation of the the K\bar{K} scalar form factors. Final state interactions in the J/\Psi \to \phi \pi\pi (K\bar{K}) processes are taken into account as rescattering effects in the system of the two pseudoscalar mesons. A very good agreement with the experimental data from DM2 and MARK-III is achieved. Furthermore, making use of SU(3) symmetry, the S-wave contribution to the \pi^+\pi^- event distribution in the J/\Psi \to \omega \pi^+\pi^- reaction is also given and the data up to energies of about 0.7 GeV are reproduced. These decays of the J/\Psi to a vector and a pair of pseudoscalars turn out to be very sensitive to OZI violating physics which we parametrize in terms of a direct OZI violation parameter and the chiral perturbation theory low energy constants L_4^r and L_6^r. These constants all come out very different from zero, lending further credit to the statement that the OZI rule is not operative in the scalar 0^{++} channel.
1012.0173
Olga Kochebina
O.Kochebina and G.Feofilov
Onset of "ridge phenomenon" in AA and pp collisions and percolation string model
null
Proceedings of the XX International Baldin Seminar on High Energy Physics Problems, 2010
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Detailed study of centrality dependence of low-p_t manifestation of so-called "near-side ridge" phenomenon is reported recently by STAR for all charged hadrons with p_t>0.15 GeV/c from AuAu collisions at 62 and 200 GeV at RHIC[1]. It is indicating the existence of the energy-dependent centrality point where some sudden changes in the correlation pattern are observed. In the present work we use the hypothesis of string percolation phase transition for the description of the onset of this ridge. One may assume that the formation of rather large "macroscopic" clusters composed of several overlapped strings extended in rapidity and localized in azimuth could be one of the possible processes leading to the observed phenomenon. This onset is characterized by some definite ("critical") number of participating nucleons. We use also another physical quantity, transverse particle density, to characterize this threshold behavior, this variable brings the transition points for two energies to coincidence [1]. So parameters of the percolation model are defined at these critical points. Also we use results of our previous calculations[2] for energy of collision 17.3 GeV based on observed threshold of anomalous suppression of J/psi. Obtained parameters are extrapolated to AA and pp collisions for energies over the range 17.3 GeV - 7000 GeV.
[ { "created": "Wed, 1 Dec 2010 12:22:49 GMT", "version": "v1" } ]
2010-12-02
[ [ "Kochebina", "O.", "" ], [ "Feofilov", "G.", "" ] ]
Detailed study of centrality dependence of low-p_t manifestation of so-called "near-side ridge" phenomenon is reported recently by STAR for all charged hadrons with p_t>0.15 GeV/c from AuAu collisions at 62 and 200 GeV at RHIC[1]. It is indicating the existence of the energy-dependent centrality point where some sudden changes in the correlation pattern are observed. In the present work we use the hypothesis of string percolation phase transition for the description of the onset of this ridge. One may assume that the formation of rather large "macroscopic" clusters composed of several overlapped strings extended in rapidity and localized in azimuth could be one of the possible processes leading to the observed phenomenon. This onset is characterized by some definite ("critical") number of participating nucleons. We use also another physical quantity, transverse particle density, to characterize this threshold behavior, this variable brings the transition points for two energies to coincidence [1]. So parameters of the percolation model are defined at these critical points. Also we use results of our previous calculations[2] for energy of collision 17.3 GeV based on observed threshold of anomalous suppression of J/psi. Obtained parameters are extrapolated to AA and pp collisions for energies over the range 17.3 GeV - 7000 GeV.
hep-ph/0111226
Sally Dawson
S. Dawson (BNL)
Higgs Boson Production Rates in Hadronic Collisions
10 pages, RevTex4, Contribution to Snowmass, 2001. Reference and table added
eConf C010630 (2001) P124
null
BNL-HET/01-39
hep-ph
null
Higgs boson production rates at hadron colliders are reviewed with particular emphasis on progress in the calculation of higher order QCD effects. Emphasis is placed on the uncertainties in the predictions for Higgs boson production. A firm understanding of these uncertainties is crucial for extracting new physics signals.
[ { "created": "Mon, 19 Nov 2001 16:12:06 GMT", "version": "v1" }, { "created": "Fri, 14 Dec 2001 13:19:46 GMT", "version": "v2" } ]
2007-05-23
[ [ "Dawson", "S.", "", "BNL" ] ]
Higgs boson production rates at hadron colliders are reviewed with particular emphasis on progress in the calculation of higher order QCD effects. Emphasis is placed on the uncertainties in the predictions for Higgs boson production. A firm understanding of these uncertainties is crucial for extracting new physics signals.
2206.06688
Guo-Yuan Huang
Guo-yuan Huang and Newton Nath
Inference of neutrino nature and Majorana CP phases from $0\nu\beta\beta$ decays with inverted mass ordering
13 pages, 7 figures, version published in EPJC
null
10.1140/epjc/s10052-022-10811-1
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Whether the neutrino mass ordering is normal or inverted remains an experimentally open issue in neutrino physics. The knowledge of neutrino mass ordering has great importance for neutrinoless double-beta ($ 0\nu\beta\beta$) decay experiments, which can establish the nature of massive neutrinos, i.e., whether they are Dirac or Majorana fermions. Recently, the KamLAND-Zen 800 measurement has reached for the first time the parameter space of the inverted ordering with a vanishing lightest neutrino mass. By assuming the inverted ordering, we attempt to derive the physical information of the neutrino nature and Majorana CP phases from a negative or positive observation of $ 0\nu\beta\beta$ decays in the near future. Moreover, the possibility of extracting the nuclear matrix element in the case of a positive observation is also examined. To avoid the ambiguity from unknown priors of neutrino masses, we adopt the maximum likelihood method instead of the Bayesian approach usually considered in previous works.
[ { "created": "Tue, 14 Jun 2022 08:44:03 GMT", "version": "v1" }, { "created": "Wed, 12 Oct 2022 08:44:26 GMT", "version": "v2" } ]
2022-10-19
[ [ "Huang", "Guo-yuan", "" ], [ "Nath", "Newton", "" ] ]
Whether the neutrino mass ordering is normal or inverted remains an experimentally open issue in neutrino physics. The knowledge of neutrino mass ordering has great importance for neutrinoless double-beta ($ 0\nu\beta\beta$) decay experiments, which can establish the nature of massive neutrinos, i.e., whether they are Dirac or Majorana fermions. Recently, the KamLAND-Zen 800 measurement has reached for the first time the parameter space of the inverted ordering with a vanishing lightest neutrino mass. By assuming the inverted ordering, we attempt to derive the physical information of the neutrino nature and Majorana CP phases from a negative or positive observation of $ 0\nu\beta\beta$ decays in the near future. Moreover, the possibility of extracting the nuclear matrix element in the case of a positive observation is also examined. To avoid the ambiguity from unknown priors of neutrino masses, we adopt the maximum likelihood method instead of the Bayesian approach usually considered in previous works.
2306.04128
Daniel Gomez Dumm
D. Gomez Dumm, S. Noguera, N. N. Scoccola
Charged meson masses under strong magnetic fields: gauge invariance and Schwinger phases
56 pages, 2 figures
null
10.1103/PhysRevD.108.016012
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the role of the Schwinger phase (SP) that appears in the propagator of a charged particle in the presence of a static and uniform magnetic field $\vec{B}$. We first note that this phase cannot be removed by a gauge transformation; far from this, we show that it plays an important role in the restoration of the symmetries of the system. Next, we analyze the effect of SPs in the one-loop corrections to charged pion and rho meson selfenergies. To carry out this analysis we consider first a simple form for the meson-quark interactions, and then we study the $\pi^+$ and $\rho^+$ propagators within the Nambu-Jona-Lasinio model, performing a numerical analysis of the $B$ dependence of meson lowest energy states. For both $\pi^+$ and $\rho^+$ mesons, we compare the numerical results arising from the full calculation -- in which SPs are included in the propagators, and meson wavefunctions correspond to states of definite Landau quantum number -- and those obtained within alternative schemes in which SPs are neglected (or somehow eliminated) and meson states are described by plane waves of definite four-momentum.
[ { "created": "Wed, 7 Jun 2023 03:52:09 GMT", "version": "v1" } ]
2023-08-02
[ [ "Dumm", "D. Gomez", "" ], [ "Noguera", "S.", "" ], [ "Scoccola", "N. N.", "" ] ]
We study the role of the Schwinger phase (SP) that appears in the propagator of a charged particle in the presence of a static and uniform magnetic field $\vec{B}$. We first note that this phase cannot be removed by a gauge transformation; far from this, we show that it plays an important role in the restoration of the symmetries of the system. Next, we analyze the effect of SPs in the one-loop corrections to charged pion and rho meson selfenergies. To carry out this analysis we consider first a simple form for the meson-quark interactions, and then we study the $\pi^+$ and $\rho^+$ propagators within the Nambu-Jona-Lasinio model, performing a numerical analysis of the $B$ dependence of meson lowest energy states. For both $\pi^+$ and $\rho^+$ mesons, we compare the numerical results arising from the full calculation -- in which SPs are included in the propagators, and meson wavefunctions correspond to states of definite Landau quantum number -- and those obtained within alternative schemes in which SPs are neglected (or somehow eliminated) and meson states are described by plane waves of definite four-momentum.
hep-ph/0003137
Igor Shovkovy
V. A. Miransky
Conformal Phase Transition, beta-Function, and Infrared Dynamics in QCD
12 pages, LaTeX, 1 eps figure. Talk given at the TMU-Yale Symposium on Dynamics of Gauge Fields, Tokyo, December 13-15, 1999. One reference is added
null
null
null
hep-ph
null
The dynamics in QCD with different number of fermion flavors N_f is discussed. The emphasis is on the description of the conformal phase transition with respect to N_f separating a phase with no confinement and chiral symmetry breaking and a phase with confinement and with chiral symmetry breaking.
[ { "created": "Tue, 14 Mar 2000 23:01:57 GMT", "version": "v1" }, { "created": "Fri, 17 Mar 2000 23:54:54 GMT", "version": "v2" } ]
2007-05-23
[ [ "Miransky", "V. A.", "" ] ]
The dynamics in QCD with different number of fermion flavors N_f is discussed. The emphasis is on the description of the conformal phase transition with respect to N_f separating a phase with no confinement and chiral symmetry breaking and a phase with confinement and with chiral symmetry breaking.
hep-ph/9710364
John Gracey
J.F. Bennett and J.A. Gracey
Determination of the anomalous dimension of gluonic operators in deep inelastic scattering at O(1/N_f)
26 latex pages, 7 postscript figures
Nucl.Phys.B517:241-268,1998
10.1016/S0550-3213(98)00021-2
LTH 414
hep-ph
null
Using large N_f methods we compute the anomalous dimension of the predominantly gluonic flavour singlet twist-2 composite operator which arises in the operator product expansion used in deep inelastic scattering. We obtain a d-dimensional expression for it which depends on the operator moment n. Its expansion in powers of epsilon = (4-d)/2 agrees with the explicit exact three loop MSbar results available for n less than or equal to 8 and allows us to determine some new information on the explicit n-dependence of the three and higher order coefficients. In particular the n-dependence of the three loop anomalous dimension gamma_{gg}(a) is determined in the C_2(G) sector at O(1/N_f).
[ { "created": "Wed, 15 Oct 1997 14:41:18 GMT", "version": "v1" } ]
2008-11-26
[ [ "Bennett", "J. F.", "" ], [ "Gracey", "J. A.", "" ] ]
Using large N_f methods we compute the anomalous dimension of the predominantly gluonic flavour singlet twist-2 composite operator which arises in the operator product expansion used in deep inelastic scattering. We obtain a d-dimensional expression for it which depends on the operator moment n. Its expansion in powers of epsilon = (4-d)/2 agrees with the explicit exact three loop MSbar results available for n less than or equal to 8 and allows us to determine some new information on the explicit n-dependence of the three and higher order coefficients. In particular the n-dependence of the three loop anomalous dimension gamma_{gg}(a) is determined in the C_2(G) sector at O(1/N_f).
hep-ph/9508326
null
Tao Huang, Shan Jin, Da-Hua Zhang and Kuang-Ta Chao
Glueball Interpretation of $\xi$(2230)
Latex file, no figures
Phys.Lett.B380:189-192,1996
10.1016/0370-2693(96)00522-9
BIHEP-TH-95-11, PUTP-95-09
hep-ph
null
On the basis of the results of $\xi(2230)\rightarrow\pi^{+}\pi^{-}, p\bar{p}$ and $K\bar{K}$, measured by the BES Collaboration in radiative J/$\psi$ decays, combined with the upper limit of Br($\xi\rightarrow p\bar{p}$)Br($\xi\rightarrow K\bar{K}$), measured by PS185 experiment, we argue that the distinctive properties of $\xi$(2230), the flavor-symmetric decays and the narrow partial decay widths to $\pi\pi$ and $K\bar{K}$ as well as its copious production in radiative J/$\psi$ decay, would strongly favor the glueball interpretation of $\xi$(2230).
[ { "created": "Mon, 21 Aug 1995 15:15:18 GMT", "version": "v1" } ]
2008-11-26
[ [ "Huang", "Tao", "" ], [ "Jin", "Shan", "" ], [ "Zhang", "Da-Hua", "" ], [ "Chao", "Kuang-Ta", "" ] ]
On the basis of the results of $\xi(2230)\rightarrow\pi^{+}\pi^{-}, p\bar{p}$ and $K\bar{K}$, measured by the BES Collaboration in radiative J/$\psi$ decays, combined with the upper limit of Br($\xi\rightarrow p\bar{p}$)Br($\xi\rightarrow K\bar{K}$), measured by PS185 experiment, we argue that the distinctive properties of $\xi$(2230), the flavor-symmetric decays and the narrow partial decay widths to $\pi\pi$ and $K\bar{K}$ as well as its copious production in radiative J/$\psi$ decay, would strongly favor the glueball interpretation of $\xi$(2230).
hep-ph/0104190
Manmohan Gupta
Gulsheen Ahuja, Monika Randhawa and Manmohan Gupta
Three flavor neutrino oscillations, LSND, SNP and ANP
16 pages, LaTex, 1 eps figure, Minor changes in the text
null
null
null
hep-ph
null
The recently reanalysed LSND data is investigated in the context of three flavor oscillations, with an emphasis on mass hierarchies and $s_{13}$. The resultant mass hierarchies and oscillation angles are tested with regard to "key" features of solar neutrinos and atmospheric neutrinos, e.g., "average" survival probability in the case of solar neutrinos, and zenith angle dependence and up-down asymmetry in the case of high energy atmospheric neutrinos. We find there are three distinct mass hierarchies, e.g., $\Delta m << \Delta M, \Delta m < \Delta M$ and $\Delta m \simeq \Delta M$. In the first and second case, the calculated range of $s_{13}$ is in agreement with the "LMA" solution of Akhmedov {\it et al.}, the lower limit on $s_{13}$ in these cases is also in agreement with the recent analysis of Garcia {\it et al.} based on the constraints of SNP, ANP and CHOOZ, therefore, strongly supporting the neutrino oscillations observed at LSND. Further, the solutions of $s_{13}$ found in the third case correspond to the value of $s_{13}$ found by Akhmedov {\it et al.} in the case of "SMA" and "LOW" solutions. A rough estimate of the possibility of the existence of CP violation in the leptonic sector is also carried out for different possible ranges of $s_{13}$, indicating that the CP asymmetries may be measureable even in the case of LSND.
[ { "created": "Thu, 19 Apr 2001 12:13:37 GMT", "version": "v1" }, { "created": "Wed, 20 Jun 2001 13:06:10 GMT", "version": "v2" } ]
2007-05-23
[ [ "Ahuja", "Gulsheen", "" ], [ "Randhawa", "Monika", "" ], [ "Gupta", "Manmohan", "" ] ]
The recently reanalysed LSND data is investigated in the context of three flavor oscillations, with an emphasis on mass hierarchies and $s_{13}$. The resultant mass hierarchies and oscillation angles are tested with regard to "key" features of solar neutrinos and atmospheric neutrinos, e.g., "average" survival probability in the case of solar neutrinos, and zenith angle dependence and up-down asymmetry in the case of high energy atmospheric neutrinos. We find there are three distinct mass hierarchies, e.g., $\Delta m << \Delta M, \Delta m < \Delta M$ and $\Delta m \simeq \Delta M$. In the first and second case, the calculated range of $s_{13}$ is in agreement with the "LMA" solution of Akhmedov {\it et al.}, the lower limit on $s_{13}$ in these cases is also in agreement with the recent analysis of Garcia {\it et al.} based on the constraints of SNP, ANP and CHOOZ, therefore, strongly supporting the neutrino oscillations observed at LSND. Further, the solutions of $s_{13}$ found in the third case correspond to the value of $s_{13}$ found by Akhmedov {\it et al.} in the case of "SMA" and "LOW" solutions. A rough estimate of the possibility of the existence of CP violation in the leptonic sector is also carried out for different possible ranges of $s_{13}$, indicating that the CP asymmetries may be measureable even in the case of LSND.
1711.08794
Kamel Benhaddou
Kamel Benhaddou
A simple expression for the four-point scalar function from Gaussian integrals and Fourier transform
This is an abridged version of arXiv:1603.05204 that focuses on the 4D four-point function and that does not use a probabilistic language
null
null
null
hep-ph math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recasting the $N$-point one loop scalar integral from Feynman to Schwinger parameters gives an integrand with a Gaussian form. By application of a Fourier transform, it is easy to derive explicit expressions for the two, three and four-point functions. The Fourier transformation disentangles singularities in the complex plane and extract their contribution as two-point functions in two dimensions. We explicitly derive a one dimensional expression for the (4D) four-point function whose integrand involves only square root and arcsine functions. This report is a condensed version of the approach developed in \cite{Benhaddou2016} which does not make use of probabilistic jargon.
[ { "created": "Thu, 23 Nov 2017 18:12:26 GMT", "version": "v1" } ]
2017-11-27
[ [ "Benhaddou", "Kamel", "" ] ]
Recasting the $N$-point one loop scalar integral from Feynman to Schwinger parameters gives an integrand with a Gaussian form. By application of a Fourier transform, it is easy to derive explicit expressions for the two, three and four-point functions. The Fourier transformation disentangles singularities in the complex plane and extract their contribution as two-point functions in two dimensions. We explicitly derive a one dimensional expression for the (4D) four-point function whose integrand involves only square root and arcsine functions. This report is a condensed version of the approach developed in \cite{Benhaddou2016} which does not make use of probabilistic jargon.
hep-ph/0012137
Ulrich Heinz
P.F. Kolb, P. Huovinen, U. Heinz, and H. Heiselberg
Elliptic flow at SPS and RHIC: from kinetic transport to hydrodynamics
7 pages incl. 5 figures; submitted to Physics Letters B; Ref. 4 and a few typos corrected; no changes in contents
Phys.Lett.B500:232-240,2001
10.1016/S0370-2693(01)00079-X
CERN-TH/2000368; LBNL-47191
hep-ph nucl-th
null
Anisotropic transverse flow is studied in Pb+Pb and Au+Au collisions at SPS and RHIC energies. The centrality and transverse momentum dependence at midrapidity of the elliptic flow coefficient v_2 is calculated in the hydrodynamic and low density limits. Hydrodynamics is found to agree well with the RHIC data for semicentral collisions up to transverse momenta of 1-1.5 GeV/c, but it considerably overestimates the measured elliptic flow at SPS energies. The low density limit LDL is inconsistent with the measured magnitude of v_2 at RHIC energies and with the shape of its p_t-dependence at both RHIC and SPS energies. The success of the hydrodynamic model points to very rapid thermalization in Au+Au collisions at RHIC and provides a serious challenge for kinetic approaches based on classical scattering of on-shell particles.
[ { "created": "Tue, 12 Dec 2000 19:36:25 GMT", "version": "v1" }, { "created": "Wed, 13 Dec 2000 19:23:25 GMT", "version": "v2" } ]
2009-10-09
[ [ "Kolb", "P. F.", "" ], [ "Huovinen", "P.", "" ], [ "Heinz", "U.", "" ], [ "Heiselberg", "H.", "" ] ]
Anisotropic transverse flow is studied in Pb+Pb and Au+Au collisions at SPS and RHIC energies. The centrality and transverse momentum dependence at midrapidity of the elliptic flow coefficient v_2 is calculated in the hydrodynamic and low density limits. Hydrodynamics is found to agree well with the RHIC data for semicentral collisions up to transverse momenta of 1-1.5 GeV/c, but it considerably overestimates the measured elliptic flow at SPS energies. The low density limit LDL is inconsistent with the measured magnitude of v_2 at RHIC energies and with the shape of its p_t-dependence at both RHIC and SPS energies. The success of the hydrodynamic model points to very rapid thermalization in Au+Au collisions at RHIC and provides a serious challenge for kinetic approaches based on classical scattering of on-shell particles.
1201.6362
Robert Poltis
Robert Poltis
Gravity Waves Seeded by Turbulence and Magnetic Fields From a First Order Phase Transition With Non-Renormalizable Electroweak Vacua
11 pages, 10 figures
null
null
null
hep-ph astro-ph.CO gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is widely believed that the standard model is a low energy effective theory which may have higher dimensional non-renormalizable operators. The existence of these new operators can lead to interesting dynamics for the evolution of the universe, including the appearance of new vacuum states. If the universe today exists in a false vacuum, there will be a non-zero probability to tunnel to the true vacuum state of the universe. Should this transition occur elsewhere in the universe, bubbles of true vacuum will nucleate and expand outwards. Bubbles that nucleate in the hot dense plasma of the early universe will feel a friction from the plasma that acts against the expansion of the bubble, until the bubble eventually reaches a steady state expansion. Unlike many bubble formation scenarios where the bubble wall velocity rapidly approaches the speed of light, friction from the hot primordial plasma can cause the expanding bubble wall to reach a terminal velocity while gravity waves are free to propagate through the hot dense plasma at the speed of light. We analyze the effects of friction on the spectrum of gravity waves caused by bubble collisions. We find that a phase transition in a model with $\phi^6$ and $\phi^8$ operators that proceeds via a detonation in the hot plasma of the early universe is unlikely. In the case of a deflagration, the gravity wave spectrum is small and would likely require a post-LISA experiment such as the Big Bang Observer, but is in principle, observable.
[ { "created": "Mon, 30 Jan 2012 21:00:01 GMT", "version": "v1" } ]
2012-02-01
[ [ "Poltis", "Robert", "" ] ]
It is widely believed that the standard model is a low energy effective theory which may have higher dimensional non-renormalizable operators. The existence of these new operators can lead to interesting dynamics for the evolution of the universe, including the appearance of new vacuum states. If the universe today exists in a false vacuum, there will be a non-zero probability to tunnel to the true vacuum state of the universe. Should this transition occur elsewhere in the universe, bubbles of true vacuum will nucleate and expand outwards. Bubbles that nucleate in the hot dense plasma of the early universe will feel a friction from the plasma that acts against the expansion of the bubble, until the bubble eventually reaches a steady state expansion. Unlike many bubble formation scenarios where the bubble wall velocity rapidly approaches the speed of light, friction from the hot primordial plasma can cause the expanding bubble wall to reach a terminal velocity while gravity waves are free to propagate through the hot dense plasma at the speed of light. We analyze the effects of friction on the spectrum of gravity waves caused by bubble collisions. We find that a phase transition in a model with $\phi^6$ and $\phi^8$ operators that proceeds via a detonation in the hot plasma of the early universe is unlikely. In the case of a deflagration, the gravity wave spectrum is small and would likely require a post-LISA experiment such as the Big Bang Observer, but is in principle, observable.
hep-ph/9608214
Hang Bae Kim
H.B. Kim and C. Munoz
An analysis of soft terms in Calabi-Yau compactifications
one reference and two footnotes added; 18 pages, LaTeX, two PostScript figures using epsfig
Z.Phys.C75:367-374,1997
10.1007/s002880050480
FTUAM 96/29
hep-ph hep-th
null
We perform an analysis of the soft supersymmetry-breaking terms arising in Calabi-Yau compactifications. The sigma-model contribution and the instanton correction to the K\"ahler potential are included in the computation. The existence of off-diagonal moduli and matter metrics gives rise to specific features as the possibility of having scalars heavier than gauginos or the presence of tachyons. Although non-universal soft terms is a natural situation, we point out that there is an interesting limit where universality is achieved. Finally, we compare these results with those of orbifold compactifications. Although they are qualitatively similar some features indeed change. For example, sum rules found in orbifold models which imply that on average the scalars are lighter than gauginos can be violated in Calabi-Yau manifolds.
[ { "created": "Fri, 2 Aug 1996 12:43:20 GMT", "version": "v1" }, { "created": "Thu, 22 Aug 1996 13:00:48 GMT", "version": "v2" } ]
2014-11-17
[ [ "Kim", "H. B.", "" ], [ "Munoz", "C.", "" ] ]
We perform an analysis of the soft supersymmetry-breaking terms arising in Calabi-Yau compactifications. The sigma-model contribution and the instanton correction to the K\"ahler potential are included in the computation. The existence of off-diagonal moduli and matter metrics gives rise to specific features as the possibility of having scalars heavier than gauginos or the presence of tachyons. Although non-universal soft terms is a natural situation, we point out that there is an interesting limit where universality is achieved. Finally, we compare these results with those of orbifold compactifications. Although they are qualitatively similar some features indeed change. For example, sum rules found in orbifold models which imply that on average the scalars are lighter than gauginos can be violated in Calabi-Yau manifolds.
1906.11575
Shi-Yuan Li
Yi Jin, Shi-Yuan Li, Yan-Rui Liu, Zhao-Xia Meng, Zong-Guo Si, and Tao Yao
Exclusive Production Ratio of Neutral over Charged Kaon Pair in $e^+e^-$ Annihilation Continuum via `Straton Model'
6 papges, 4 figures. This paper is dedicated to M. Gell-Mann In v2 several refs. added
Phys. Rev. C 102, 015201 (2020)
10.1103/PhysRevC.102.015201
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A completely relativistic quark model in the Bethe-Salpter framework is employed to calculate the exclusive production ratio of the neutral over charged Kaon pair in $e^+e^-$ annihilation continuum region for center of mass energies smaller than the $J/\Psi$ mass. The valence quark charge plays the key r\^{o}le. The cancellation of the diagrams for the same charge case (in $K_S + K_L$) and the non-cancellation of the diagrams for the different charge case (in $K^-+K^+$) lead to the ratio as $(m_s-m_d)^2/M_{Kaon}^2 \sim 1/10$.
[ { "created": "Thu, 27 Jun 2019 12:02:34 GMT", "version": "v1" }, { "created": "Tue, 9 Jul 2019 08:41:33 GMT", "version": "v2" } ]
2020-07-08
[ [ "Jin", "Yi", "" ], [ "Li", "Shi-Yuan", "" ], [ "Liu", "Yan-Rui", "" ], [ "Meng", "Zhao-Xia", "" ], [ "Si", "Zong-Guo", "" ], [ "Yao", "Tao", "" ] ]
A completely relativistic quark model in the Bethe-Salpter framework is employed to calculate the exclusive production ratio of the neutral over charged Kaon pair in $e^+e^-$ annihilation continuum region for center of mass energies smaller than the $J/\Psi$ mass. The valence quark charge plays the key r\^{o}le. The cancellation of the diagrams for the same charge case (in $K_S + K_L$) and the non-cancellation of the diagrams for the different charge case (in $K^-+K^+$) lead to the ratio as $(m_s-m_d)^2/M_{Kaon}^2 \sim 1/10$.
hep-ph/9807320
null
Carlos C. Meca and Joao P. Silva
Detecting new physics contributions to the D0-D0bar mixing through their effects on B decays
10 pages, Revtex, no figures. To appear in PRL
Phys.Rev.Lett. 81 (1998) 1377-1380
10.1103/PhysRevLett.81.1377
CFNUL/98-03
hep-ph
null
New physics effects may yield a detectable mass difference in the D0-D0bar system, Delta m_D. Here we show that this has an important impact on some B --> D decays. The effect involves a new source of CP violation, which arises from the interference between the phases in the B --> D decays and those in the D0-D0bar system. This interference is naturally large. New physics may well manifest itself through Delta m_D contributions to these B decays.
[ { "created": "Thu, 9 Jul 1998 21:59:05 GMT", "version": "v1" } ]
2009-10-31
[ [ "Meca", "Carlos C.", "" ], [ "Silva", "Joao P.", "" ] ]
New physics effects may yield a detectable mass difference in the D0-D0bar system, Delta m_D. Here we show that this has an important impact on some B --> D decays. The effect involves a new source of CP violation, which arises from the interference between the phases in the B --> D decays and those in the D0-D0bar system. This interference is naturally large. New physics may well manifest itself through Delta m_D contributions to these B decays.
hep-ph/9804274
Alessandro Strumia
A. Strumia
Two-loop heavy top corrections to the b --> s gamma decay
10 pages, 3 figures. (v2): reference added
Nucl.Phys.B532:28-42,1998
10.1016/S0550-3213(98)00462-3
IFUP-TH 16/98
hep-ph
null
We compute the two-loop corrections to the coefficient of the b --> s gamma magnetic penguin present in the limits of heavy top and/or heavy higgs. This kind of corrections affects in a significant way the observables measured at LEP. On the contrary we find that, due to a numerical accident, the correction to BR(B --> X_s gamma) is negligible (below the 1% level for any possible value of the higgs mass) when the leading order result is expressed in the usual way in terms of the semileptonic BR(B --> X_c \bar{e}\nu).
[ { "created": "Sat, 11 Apr 1998 10:41:03 GMT", "version": "v1" }, { "created": "Mon, 20 Apr 1998 14:25:16 GMT", "version": "v2" } ]
2009-10-09
[ [ "Strumia", "A.", "" ] ]
We compute the two-loop corrections to the coefficient of the b --> s gamma magnetic penguin present in the limits of heavy top and/or heavy higgs. This kind of corrections affects in a significant way the observables measured at LEP. On the contrary we find that, due to a numerical accident, the correction to BR(B --> X_s gamma) is negligible (below the 1% level for any possible value of the higgs mass) when the leading order result is expressed in the usual way in terms of the semileptonic BR(B --> X_c \bar{e}\nu).
hep-ph/9406403
null
Pran Nath and R. Arnowitt
Susy Particles
16 pages+ 6 figs(hard copies available on request)
null
null
CERN-TH.7227/94, NUB-TH.3089/94,and CTP-TAMU-28/94
hep-ph
null
Analysis of the SUSY spectrum in supergravity unified models is given under the naturalness criterion that the universal scalar mass $(m_0)$ and the gluino mass $(m_{\tilde g})$ satisfy the constraint $m_0, m_{\tilde g}$ less than or equal to 1 TeV. The SUSY spectrum is analysed in four different scenarios: (1) minimal supergravity models ignoring proton decay from dimension five operators, (2) imposing proton stability constraint in supergravity models with SU(5) type embedding which allow proton decay via dimension five operators, (3) with inclusion of dark matter constraints in models of type (1), and (4) with inclusion of dark matter constraint in models of type (2). It is found that there is a very strong upper limit on the light chargino mass in models of type (4), i.e., the light chargino mass is less than or equals 120 GeV.
[ { "created": "Mon, 27 Jun 1994 11:02:44 GMT", "version": "v1" } ]
2009-09-25
[ [ "Nath", "Pran", "" ], [ "Arnowitt", "R.", "" ] ]
Analysis of the SUSY spectrum in supergravity unified models is given under the naturalness criterion that the universal scalar mass $(m_0)$ and the gluino mass $(m_{\tilde g})$ satisfy the constraint $m_0, m_{\tilde g}$ less than or equal to 1 TeV. The SUSY spectrum is analysed in four different scenarios: (1) minimal supergravity models ignoring proton decay from dimension five operators, (2) imposing proton stability constraint in supergravity models with SU(5) type embedding which allow proton decay via dimension five operators, (3) with inclusion of dark matter constraints in models of type (1), and (4) with inclusion of dark matter constraint in models of type (2). It is found that there is a very strong upper limit on the light chargino mass in models of type (4), i.e., the light chargino mass is less than or equals 120 GeV.
0810.4718
Volker D. Burkert
Volker D. Burkert
CLAS12 and its initial Science Program at the Jefferson Lab Upgrade
9 pages, 14 figures, Workshop on RICH for CLAS12
null
null
null
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An overview of the CLAS12 detector is presented and the initial physics program after the energy-doubling of the Jefferson Lab electron accelerator. Construction of the 12 GeV upgrade project has started October 2008. A broad program has been developed to map the nucleon's 3-dimensional spin and flavor content through the measurement of deeply exclusive and semi-inclusive processes. Other programs include forward distribution function to large $x_{B} \le 0.85$ and of the quark and gluon polarized distribution functions, as well as nucleon ground state and transition form factors at high $Q^2$. The 12 GeV electron beam and the large acceptance of CLAS12 are also well suited to explore hadronization properties using the nucleus as a laboratory
[ { "created": "Sun, 26 Oct 2008 21:06:09 GMT", "version": "v1" }, { "created": "Fri, 7 Nov 2008 19:04:57 GMT", "version": "v2" } ]
2008-11-07
[ [ "Burkert", "Volker D.", "" ] ]
An overview of the CLAS12 detector is presented and the initial physics program after the energy-doubling of the Jefferson Lab electron accelerator. Construction of the 12 GeV upgrade project has started October 2008. A broad program has been developed to map the nucleon's 3-dimensional spin and flavor content through the measurement of deeply exclusive and semi-inclusive processes. Other programs include forward distribution function to large $x_{B} \le 0.85$ and of the quark and gluon polarized distribution functions, as well as nucleon ground state and transition form factors at high $Q^2$. The 12 GeV electron beam and the large acceptance of CLAS12 are also well suited to explore hadronization properties using the nucleus as a laboratory
1305.4916
Bo-Qiang Ma
Huilin Qu, Bo-Qiang Ma
New mixing pattern for neutrinos
4 pages, 1 figure. Final version to appear in PRD
Phys. Rev. D 88 (2013) 037301
10.1103/PhysRevD.88.037301
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new mixing pattern for neutrinos with a nonzero mixing angle $\theta_{13}$. Under a simple form, it agrees well with current neutrino oscillation data and displays a number of intriguing features including the $\mu$-$\tau$ interchange symmetry $|U_{\mu i}|=|U_{\tau i}|$, $(i=1,2,3)$, the trimaximal mixing $|U_{\e 2}|=|U_{\mu 2}|=|U_{\tau 2}|=1/\sqrt{3}$, the self-complementarity relation $\theta_1+\theta_3=45\deg$, together with the maximal Dirac CP violation as a prediction.
[ { "created": "Tue, 21 May 2013 19:01:06 GMT", "version": "v1" }, { "created": "Wed, 7 Aug 2013 17:36:23 GMT", "version": "v2" } ]
2013-08-27
[ [ "Qu", "Huilin", "" ], [ "Ma", "Bo-Qiang", "" ] ]
We propose a new mixing pattern for neutrinos with a nonzero mixing angle $\theta_{13}$. Under a simple form, it agrees well with current neutrino oscillation data and displays a number of intriguing features including the $\mu$-$\tau$ interchange symmetry $|U_{\mu i}|=|U_{\tau i}|$, $(i=1,2,3)$, the trimaximal mixing $|U_{\e 2}|=|U_{\mu 2}|=|U_{\tau 2}|=1/\sqrt{3}$, the self-complementarity relation $\theta_1+\theta_3=45\deg$, together with the maximal Dirac CP violation as a prediction.
1903.09644
Dreyer Fr\'ed\'eric
Stefano Carrazza and Fr\'ed\'eric A. Dreyer
Jet grooming through reinforcement learning
11 pages, 10 figures, code available at https://github.com/JetsGame/GroomRL, updated to match published version
Phys. Rev. D 100, 014014 (2019)
10.1103/PhysRevD.100.014014
null
hep-ph cs.LG hep-ex stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We introduce a novel implementation of a reinforcement learning (RL) algorithm which is designed to find an optimal jet grooming strategy, a critical tool for collider experiments. The RL agent is trained with a reward function constructed to optimize the resulting jet properties, using both signal and background samples in a simultaneous multi-level training. We show that the grooming algorithm derived from the deep RL agent can match state-of-the-art techniques used at the Large Hadron Collider, resulting in improved mass resolution for boosted objects. Given a suitable reward function, the agent learns how to train a policy which optimally removes soft wide-angle radiation, allowing for a modular grooming technique that can be applied in a wide range of contexts. These results are accessible through the corresponding GroomRL framework.
[ { "created": "Fri, 22 Mar 2019 18:00:00 GMT", "version": "v1" }, { "created": "Sun, 21 Jul 2019 17:53:08 GMT", "version": "v2" } ]
2019-07-24
[ [ "Carrazza", "Stefano", "" ], [ "Dreyer", "Frédéric A.", "" ] ]
We introduce a novel implementation of a reinforcement learning (RL) algorithm which is designed to find an optimal jet grooming strategy, a critical tool for collider experiments. The RL agent is trained with a reward function constructed to optimize the resulting jet properties, using both signal and background samples in a simultaneous multi-level training. We show that the grooming algorithm derived from the deep RL agent can match state-of-the-art techniques used at the Large Hadron Collider, resulting in improved mass resolution for boosted objects. Given a suitable reward function, the agent learns how to train a policy which optimally removes soft wide-angle radiation, allowing for a modular grooming technique that can be applied in a wide range of contexts. These results are accessible through the corresponding GroomRL framework.
hep-ph/0405242
Aaron Pierce
Maurizio Piai (1), Aaron Pierce (2 and 3), Jay Wacker (3) ((1) Yale, (2) SLAC, (3) Stanford)
Composite Vector Mesons from QCD to the Little Higgs
30 pages, 10 figures
null
null
SLAC-PUB-10457
hep-ph
null
We review how the rho meson can be modeled in an effective theory and discuss the implications of applying this approach to heavier spin-one resonances. Georgi's vector limit is explored, and its relationship to locality in a deconstructed extra-dimension is discussed. We then apply the formalism for rho's to strongly coupled theories of electroweak symmetry breaking, studying the lightest spin-one techni-rho resonances. Understanding these new particles in Little Higgs models can shed light on previously incalculable, ultraviolet sensitive physics, including the mass of the Higgs boson.
[ { "created": "Mon, 24 May 2004 21:02:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Piai", "Maurizio", "", "2 and 3" ], [ "Pierce", "Aaron", "", "2 and 3" ], [ "Wacker", "Jay", "" ] ]
We review how the rho meson can be modeled in an effective theory and discuss the implications of applying this approach to heavier spin-one resonances. Georgi's vector limit is explored, and its relationship to locality in a deconstructed extra-dimension is discussed. We then apply the formalism for rho's to strongly coupled theories of electroweak symmetry breaking, studying the lightest spin-one techni-rho resonances. Understanding these new particles in Little Higgs models can shed light on previously incalculable, ultraviolet sensitive physics, including the mass of the Higgs boson.
hep-ph/9502246
Nicholas Tracas
G. K. Leontaris and N. D. Tracas
Soft SUSY Masses and the Dynamical Determination of the Gravitino Mass
14 pages, plain LATEX plus 7 figures sent in a different file
Phys.Lett. B351 (1995) 487-496
10.1016/0370-2693(95)00433-L
IOA 313/95, NTUA 47/95 Report
hep-ph
null
We discuss in detail the possibility of determining dynamicaly the gravitino mass $m_{3/2}$, which is related to the supersymmetry breaking scale, within the minimal supersymmetric standard model (MSSM). Using the complete MSSM spectrum, we minimize the vacuum energy including one-loop corrections and a cosmological term of ${\cal O}(m_{3/2}^4)$ induced by the underlying fundamental theory. We find that both terms are necessary to determine dynamically the gravitino mass. Other useful constraints for the low energy phenomenology are also obtained.
[ { "created": "Tue, 7 Feb 1995 17:36:13 GMT", "version": "v1" } ]
2009-10-28
[ [ "Leontaris", "G. K.", "" ], [ "Tracas", "N. D.", "" ] ]
We discuss in detail the possibility of determining dynamicaly the gravitino mass $m_{3/2}$, which is related to the supersymmetry breaking scale, within the minimal supersymmetric standard model (MSSM). Using the complete MSSM spectrum, we minimize the vacuum energy including one-loop corrections and a cosmological term of ${\cal O}(m_{3/2}^4)$ induced by the underlying fundamental theory. We find that both terms are necessary to determine dynamically the gravitino mass. Other useful constraints for the low energy phenomenology are also obtained.
1303.5332
J. -Alexis Rodriguez L.
J. M. Cabarcas and J.-Alexis Rodriguez
Electric charge quantization in SU(3)XSU(4)XU(1) models
9 pages
Modern Physics Letters A 29 (06) (2014)
10.1142/S0217732314500321
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We obtain electric charge quantization in the context of models based on the gauge symmetry group SU(3) X SU(4) X U(1). The gauge models studied include three families to cancel out anomalies and a set of scalar fields to break spontaneously the symmetry. To show the electric charge quantization, we use clasical symmetry conditions and quantum quiral anomaly conditions.
[ { "created": "Thu, 21 Mar 2013 17:01:22 GMT", "version": "v1" } ]
2015-06-15
[ [ "Cabarcas", "J. M.", "" ], [ "Rodriguez", "J. -Alexis", "" ] ]
We obtain electric charge quantization in the context of models based on the gauge symmetry group SU(3) X SU(4) X U(1). The gauge models studied include three families to cancel out anomalies and a set of scalar fields to break spontaneously the symmetry. To show the electric charge quantization, we use clasical symmetry conditions and quantum quiral anomaly conditions.
1906.06352
Fabrizio Rompineve
Jan Olle, Oriol Pujolas and Fabrizio Rompineve
Oscillons and Dark Matter
42 pages, 12 figures. v2: references added, further minor additions in the text
null
10.1088/1475-7516/2020/02/006
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Oscillons are bound states sustained by self-interactions that appear in rather generic scalar models. They can be extremely long-lived and in the context of cosmology they have a built-in formation mechanism - parametric resonance instability. These features suggest that oscillons can affect the standard picture of scalar ultra-light dark matter (ULDM) models. We explore this idea along two directions. First, we investigate numerically oscillon lifetimes and their dependence on the shape of the potential. We find that scalar potentials that occur in well motivated axion-like models can lead to oscillons that live up to $10^8$ cycles or more. Second, we discuss the observational constraints on the ULDM models once the presence of oscillons is taken into account. For a wide range of axion masses, oscillons decay around or after matter-radiation equality and can thus act as early seeds for structure formation. We also discuss the possibility that oscillons survive up to today. In this case they can most easily play the role of dark matter.
[ { "created": "Fri, 14 Jun 2019 18:09:50 GMT", "version": "v1" }, { "created": "Tue, 11 Feb 2020 18:03:07 GMT", "version": "v2" } ]
2020-03-04
[ [ "Olle", "Jan", "" ], [ "Pujolas", "Oriol", "" ], [ "Rompineve", "Fabrizio", "" ] ]
Oscillons are bound states sustained by self-interactions that appear in rather generic scalar models. They can be extremely long-lived and in the context of cosmology they have a built-in formation mechanism - parametric resonance instability. These features suggest that oscillons can affect the standard picture of scalar ultra-light dark matter (ULDM) models. We explore this idea along two directions. First, we investigate numerically oscillon lifetimes and their dependence on the shape of the potential. We find that scalar potentials that occur in well motivated axion-like models can lead to oscillons that live up to $10^8$ cycles or more. Second, we discuss the observational constraints on the ULDM models once the presence of oscillons is taken into account. For a wide range of axion masses, oscillons decay around or after matter-radiation equality and can thus act as early seeds for structure formation. We also discuss the possibility that oscillons survive up to today. In this case they can most easily play the role of dark matter.
1407.0057
Nikolai Zerf
Nikolai Zerf
Bottom Quark Mass from $\Upsilon$ Sum Rules to ${\cal O}(\alpha_s^3)$
Contribution to the proceedings of "Loops and Legs in Quantum Field Theory - LL 2014", 27 April - 2 May 2014, Weimar, Germany
null
null
Alberta Thy 12-14
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the deterimination of the bottom quark mass using non-relativistic $\Upsilon$ Sum Rules at $\text{N}^3\text{LO}^*$[1]. The explicit dependence of $\overline{m}_b(\overline{m}_b)$ on the input value $\alpha_s(M_Z)$ is given for the first time.
[ { "created": "Mon, 30 Jun 2014 21:14:07 GMT", "version": "v1" } ]
2014-07-02
[ [ "Zerf", "Nikolai", "" ] ]
We present the deterimination of the bottom quark mass using non-relativistic $\Upsilon$ Sum Rules at $\text{N}^3\text{LO}^*$[1]. The explicit dependence of $\overline{m}_b(\overline{m}_b)$ on the input value $\alpha_s(M_Z)$ is given for the first time.
hep-ph/9411205
Bob Holdom
B. Holdom
New strong sector, odd-parity processes, and the Tevatron
8 pages, uuencoded PS file, try ghostscript or direct printing rather than ghostview, PS file of paper without figure is available on WWW at http://bigmac2.physics.utoronto.ca/BHpapers.html
Phys.Lett. B344 (1995) 355-358
10.1016/0370-2693(94)01494-W
UTPT-94-26
hep-ph
null
The color-octet isosinglet "rho" of a new strong-interaction sector is readily produced in ppbar collisions. Its odd-parity decay to an "eta" and a gluon may exceed its decay rate to dijets. At center of mass energies sufficiently greater than the colored "rho" mass, the odd-parity production of ("omega" + colored "eta") or ("rho" + colored "pion") may be comparable to ttbar production. Considering that the "omega" has a dominant odd-parity decay mode, we end up with (Z, W, or gamma) + 4 jet events with two of the jets containing b or bbar.
[ { "created": "Tue, 1 Nov 1994 22:13:27 GMT", "version": "v1" } ]
2009-10-28
[ [ "Holdom", "B.", "" ] ]
The color-octet isosinglet "rho" of a new strong-interaction sector is readily produced in ppbar collisions. Its odd-parity decay to an "eta" and a gluon may exceed its decay rate to dijets. At center of mass energies sufficiently greater than the colored "rho" mass, the odd-parity production of ("omega" + colored "eta") or ("rho" + colored "pion") may be comparable to ttbar production. Considering that the "omega" has a dominant odd-parity decay mode, we end up with (Z, W, or gamma) + 4 jet events with two of the jets containing b or bbar.
2205.02140
V\'ictor Miralles
Gauthier Durieux, Abel Guti\'errez Camacho, Luca Mantani, V\'ictor Miralles, Marcos Miralles L\'opez, Mar\'ia Moreno Ll\'acer, Ren\'e Poncelet, Eleni Vryonidou, Marcel Vos
Snowmass White Paper: prospects for the measurement of top-quark couplings
Contribution Snowmass 2021
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this contribution to the 2021 Snowmass community planning exercise that informs the American strategy for particle physics, we present the prospects for measurements of the top-quark couplings at future colliders. Projections are presented for the high luminosity phase of the Large Hadron Collider and a future Higgs/electroweak/top factory electron-positron collider. Results are presented for the expected bounds on Wilson coefficients of the relevant SMEFT operators from a global fit to the top physics sector.
[ { "created": "Wed, 4 May 2022 15:48:20 GMT", "version": "v1" } ]
2022-05-05
[ [ "Durieux", "Gauthier", "" ], [ "Camacho", "Abel Gutiérrez", "" ], [ "Mantani", "Luca", "" ], [ "Miralles", "Víctor", "" ], [ "López", "Marcos Miralles", "" ], [ "Llácer", "María Moreno", "" ], [ "Poncelet", "René", "" ], [ "Vryonidou", "Eleni", "" ], [ "Vos", "Marcel", "" ] ]
In this contribution to the 2021 Snowmass community planning exercise that informs the American strategy for particle physics, we present the prospects for measurements of the top-quark couplings at future colliders. Projections are presented for the high luminosity phase of the Large Hadron Collider and a future Higgs/electroweak/top factory electron-positron collider. Results are presented for the expected bounds on Wilson coefficients of the relevant SMEFT operators from a global fit to the top physics sector.
1602.02433
Wei Chen
Hua-Xing Chen, Er-Liang Cui, Wei Chen, T. G. Steele, Xiang Liu, and Shi-Lin Zhu
QCD sum rule study of hidden-charm pentaquarks
18 pages, 5 figures and 3 tables. Accepted by Eur. Phys. J. C
Eur.Phys.J. C76 (2016) no.10, 572
10.1140/epjc/s10052-016-4438-5
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the mass spectra of hidden-charm pentaquarks having spin $J = {1\over2}/{3\over2}/{5\over2}$ and quark contents $uud c \bar c$. We systematically construct all the relevant local hidden-charm pentaquark currents, and select some of them to perform QCD sum rule analyses. We find that the $P_c(4380)$ and $P_c(4450)$ can be identified as hidden-charm pentaquark states composed of an anti-charmed meson and a charmed baryon. Besides them, we also find a) the lowest-lying hidden-charm pentaquark state of $J^P = 1/2^-$ has the mass $4.33^{+0.17}_{-0.13}$ GeV, while the one of $J^P = 1/2^+$ is significantly higher, that is around $4.7-4.9$ GeV; b) the lowest-lying hidden-charm pentaquark state of $J^P = 3/2^-$ has the mass $4.37^{+0.18}_{-0.13}$ GeV, consistent with the $P_c(4380)$ of $J^P = 3/2^-$, while the one of $J^P = 3/2^+$ is also significantly higher, that is above $4.6$ GeV; c) the hidden-charm pentaquark state of $J^P = 5/2^-$ has a mass around $4.5-4.6$ GeV, slightly larger than the $P_c(4450)$ of $J^P = 5/2^+$.
[ { "created": "Sun, 7 Feb 2016 22:08:16 GMT", "version": "v1" }, { "created": "Tue, 25 Oct 2016 17:46:18 GMT", "version": "v2" } ]
2016-10-31
[ [ "Chen", "Hua-Xing", "" ], [ "Cui", "Er-Liang", "" ], [ "Chen", "Wei", "" ], [ "Steele", "T. G.", "" ], [ "Liu", "Xiang", "" ], [ "Zhu", "Shi-Lin", "" ] ]
We study the mass spectra of hidden-charm pentaquarks having spin $J = {1\over2}/{3\over2}/{5\over2}$ and quark contents $uud c \bar c$. We systematically construct all the relevant local hidden-charm pentaquark currents, and select some of them to perform QCD sum rule analyses. We find that the $P_c(4380)$ and $P_c(4450)$ can be identified as hidden-charm pentaquark states composed of an anti-charmed meson and a charmed baryon. Besides them, we also find a) the lowest-lying hidden-charm pentaquark state of $J^P = 1/2^-$ has the mass $4.33^{+0.17}_{-0.13}$ GeV, while the one of $J^P = 1/2^+$ is significantly higher, that is around $4.7-4.9$ GeV; b) the lowest-lying hidden-charm pentaquark state of $J^P = 3/2^-$ has the mass $4.37^{+0.18}_{-0.13}$ GeV, consistent with the $P_c(4380)$ of $J^P = 3/2^-$, while the one of $J^P = 3/2^+$ is also significantly higher, that is above $4.6$ GeV; c) the hidden-charm pentaquark state of $J^P = 5/2^-$ has a mass around $4.5-4.6$ GeV, slightly larger than the $P_c(4450)$ of $J^P = 5/2^+$.
1311.4506
Pilar Coloma
Pilar Coloma, Patrick Huber, Chun-Min Jen and Camillo Mariani
Neutrino-nucleus interaction models and their impact on oscillation analyses
23 pages, 9 figures. Version accepted for publication in Phys. Rev. D
Phys. Rev. D 89, 073015 (2014)
10.1103/PhysRevD.89.073015
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In neutrino oscillation experiments, neutrino interactions at the detector are simulated using event generators which attempt to reflect our understanding of nuclear physics. We study the impact of different neutrino interactions and nuclear models on the determination of neutrino oscillation parameters. We use two independent neutrino event generators, GENIE and GiBUU, and apply them to a setup with a conventional neutrino beam aiming at a water \v{C}erenkov detector, for which only the QE-like sample is selected. Subsequently, we perform a fit to the oscillation parameters in the $\nu_\mu$ disappearance channel.
[ { "created": "Mon, 18 Nov 2013 19:31:34 GMT", "version": "v1" }, { "created": "Fri, 6 Dec 2013 17:56:38 GMT", "version": "v2" }, { "created": "Sun, 30 Mar 2014 18:00:41 GMT", "version": "v3" } ]
2014-04-23
[ [ "Coloma", "Pilar", "" ], [ "Huber", "Patrick", "" ], [ "Jen", "Chun-Min", "" ], [ "Mariani", "Camillo", "" ] ]
In neutrino oscillation experiments, neutrino interactions at the detector are simulated using event generators which attempt to reflect our understanding of nuclear physics. We study the impact of different neutrino interactions and nuclear models on the determination of neutrino oscillation parameters. We use two independent neutrino event generators, GENIE and GiBUU, and apply them to a setup with a conventional neutrino beam aiming at a water \v{C}erenkov detector, for which only the QE-like sample is selected. Subsequently, we perform a fit to the oscillation parameters in the $\nu_\mu$ disappearance channel.