id
stringlengths
9
14
submitter
stringlengths
1
56
authors
stringlengths
5
7.68k
title
stringlengths
3
299
comments
stringlengths
1
1.15k
journal-ref
stringlengths
9
298
doi
stringlengths
12
97
report-no
stringlengths
3
341
categories
stringclasses
869 values
license
stringclasses
9 values
orig_abstract
stringlengths
16
2.44k
versions
listlengths
1
39
update_date
stringlengths
10
10
authors_parsed
listlengths
1
565
abstract
stringlengths
13
2.44k
2007.02898
Digesh Raut
Nobuchika Okada, Satomi Okada, Digesh Raut, and Qaisar Shafi
Dark Matter $Z^\prime$ and XENON1T Excess from $U(1)_X$ Extended Standard Model
6 pages, version published in PLB
null
10.1016/j.physletb.2020.135785
null
hep-ph astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A gauged $U(1)_X$ symmetry appended to the Standard Model (SM) is particularly well-motivated since it can account for the light neutrino masses by the seesaw mechanism, explain the origin of baryon asymmetry of the universe via leptogenesis, and help implement successful cosmological inflation with the $U(1)_X$ breaking Higgs field as the inflaton. In this framework, we propose a light dark matter (DM) scenario in which the $U(1)_X$ gauge boson $Z^\prime$ behaves as a DM particle in the universe. We discuss how this scenario with $Z^\prime$ mass of a few keV and a $U(1)_X$ gauge coupling $g_X \simeq 10^{-16}$ can nicely fit the excess in the electronic recoil energy spectrum recently reported by the XENON1T collaboration. In order to reproduce the observed DM relic density in the presence of such a tiny gauge coupling, we propose an extension of the model to a two-component DM scenario. The $Z^\prime$ DM density can be comparable to the observed DM density by the freeze-in mechanism through the coupling of $Z^\prime$ boson to a partner Higgs-portal scalar DM with a large $U(1)_X$ charge.
[ { "created": "Mon, 6 Jul 2020 17:22:00 GMT", "version": "v1" }, { "created": "Sun, 7 Mar 2021 20:29:29 GMT", "version": "v2" } ]
2021-03-09
[ [ "Okada", "Nobuchika", "" ], [ "Okada", "Satomi", "" ], [ "Raut", "Digesh", "" ], [ "Shafi", "Qaisar", "" ] ]
A gauged $U(1)_X$ symmetry appended to the Standard Model (SM) is particularly well-motivated since it can account for the light neutrino masses by the seesaw mechanism, explain the origin of baryon asymmetry of the universe via leptogenesis, and help implement successful cosmological inflation with the $U(1)_X$ breaking Higgs field as the inflaton. In this framework, we propose a light dark matter (DM) scenario in which the $U(1)_X$ gauge boson $Z^\prime$ behaves as a DM particle in the universe. We discuss how this scenario with $Z^\prime$ mass of a few keV and a $U(1)_X$ gauge coupling $g_X \simeq 10^{-16}$ can nicely fit the excess in the electronic recoil energy spectrum recently reported by the XENON1T collaboration. In order to reproduce the observed DM relic density in the presence of such a tiny gauge coupling, we propose an extension of the model to a two-component DM scenario. The $Z^\prime$ DM density can be comparable to the observed DM density by the freeze-in mechanism through the coupling of $Z^\prime$ boson to a partner Higgs-portal scalar DM with a large $U(1)_X$ charge.
1506.06351
Andrea Addazi AndAdd
Andrea Addazi
Direct generation of a Majorana mass for the Neutron from Exotic Instantons
Version accepted by Physics Letter B
null
10.1016/j.physletb.2016.04.018
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss a new mechanism in which non-perturbative quantum gravity effects directly generate a Majorana mass for the neutron. In particular, in string theory, exotic instantons can generate an effective six quark operator by calculable mixed disk amplitudes. In a low string scale scenario, with $M_{S}\simeq 10\div 10^{5}\, \rm TeV$, a neutron-antineutron oscillation can be reached in the next generation of experiments. we argue that protons and neutralinos are not destabilized and that dangerous FCNCs are not generated. We show an example of quiver theories, locally free by tadpoles and anomalies, reproducing MSSM plus a Majorana neutron and a Majorana neutrino. These models naturally provide a viable baryogenesis mechanism by resonant RH neutrino decays, as well as a stable WIMP-like dark matter. We also discuss how LHC data will provide useful inputs for our model, in the immediate future, testing several different regions of the parameter space. Such a mechanism represents a simple and calculable counter-example to the Wilsonian UV completion of effective non-renormalizable operators.
[ { "created": "Sun, 21 Jun 2015 11:35:17 GMT", "version": "v1" }, { "created": "Mon, 31 Aug 2015 12:44:03 GMT", "version": "v2" }, { "created": "Tue, 15 Dec 2015 09:51:49 GMT", "version": "v3" }, { "created": "Wed, 6 Apr 2016 14:29:08 GMT", "version": "v4" } ]
2016-05-04
[ [ "Addazi", "Andrea", "" ] ]
We discuss a new mechanism in which non-perturbative quantum gravity effects directly generate a Majorana mass for the neutron. In particular, in string theory, exotic instantons can generate an effective six quark operator by calculable mixed disk amplitudes. In a low string scale scenario, with $M_{S}\simeq 10\div 10^{5}\, \rm TeV$, a neutron-antineutron oscillation can be reached in the next generation of experiments. we argue that protons and neutralinos are not destabilized and that dangerous FCNCs are not generated. We show an example of quiver theories, locally free by tadpoles and anomalies, reproducing MSSM plus a Majorana neutron and a Majorana neutrino. These models naturally provide a viable baryogenesis mechanism by resonant RH neutrino decays, as well as a stable WIMP-like dark matter. We also discuss how LHC data will provide useful inputs for our model, in the immediate future, testing several different regions of the parameter space. Such a mechanism represents a simple and calculable counter-example to the Wilsonian UV completion of effective non-renormalizable operators.
1203.5137
Sergey Troshin
S. M. Troshin, N. E. Tyurin
On the large-$t$ elastic scattering at $\sqrt{s}=7$ TeV
7 pages, 1 figure, enlarged version
Mod. Phys. Lett. A, Vol. 27, No. 20 (2012) 1250111
10.1142/S021773231250118
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss discrimination of the scattering mechanisms on the basis of functional dependencies of the large-$t$ elastic scattering suggested by the recent data from the TOTEM experiment. It is shown that Orear exponent is in a better agreement with the data than the power-like dependence used by the TOTEM. This implies that the collective dynamics is dominating over the point-like mechanism related to the scattering of the proton constituents.
[ { "created": "Wed, 21 Mar 2012 12:37:20 GMT", "version": "v1" }, { "created": "Sat, 12 May 2012 07:19:33 GMT", "version": "v2" } ]
2012-06-15
[ [ "Troshin", "S. M.", "" ], [ "Tyurin", "N. E.", "" ] ]
We discuss discrimination of the scattering mechanisms on the basis of functional dependencies of the large-$t$ elastic scattering suggested by the recent data from the TOTEM experiment. It is shown that Orear exponent is in a better agreement with the data than the power-like dependence used by the TOTEM. This implies that the collective dynamics is dominating over the point-like mechanism related to the scattering of the proton constituents.
hep-ph/0109240
Jonathan L. Rosner
Jonathan L. Rosner
CP Symmetry Violation
5 pages, LaTeX, no figures, to be published in {\it Macmillan Encylopedia of Physics, Supplement: Elementary Particle Physics}, edited by John S. Rigden, Jonathan Bagger, and Roger H. Stuewer (Macmillan Reference USA, New York, 2002). Revised version
null
null
EFI-01-40
hep-ph
null
An elementary description of CP violation for the non-specialist is presented. This article, for publication in {\it Macmillan Encylopedia of Physics, Supplement: Elementary Particle Physics}, is being submitted to the Archive for comments by colleagues.
[ { "created": "Tue, 25 Sep 2001 20:09:26 GMT", "version": "v1" }, { "created": "Mon, 15 Oct 2001 20:21:54 GMT", "version": "v2" } ]
2007-05-23
[ [ "Rosner", "Jonathan L.", "" ] ]
An elementary description of CP violation for the non-specialist is presented. This article, for publication in {\it Macmillan Encylopedia of Physics, Supplement: Elementary Particle Physics}, is being submitted to the Archive for comments by colleagues.
1201.2949
Howard Baer
Howard Baer, Vernon Barger, Andre Lessa, Warintorn Sreethawong and Xerxes Tata
Wh plus missing-E_T signature from gaugino pair production at the LHC
5 pages with 4 .eps figures
null
10.1103/PhysRevD.85.055022
UH-511-1186-12
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In SUSY models with heavy squarks and gaugino mass unification, the gaugino pair production reaction pp-> \tw_1^\pm\tz_2 dominates gluino pair production for m_{\tg}\agt 1 TeV at LHC with \sqrt{s}=14 TeV (LHC14). For this mass range, the two-body decays \tw_1\to W\tz_1 and \tz_2\to h\tz_1 are expected to dominate the chargino and neutralino branching fractions. By searching for \ell b\bar{b}+MET events from \tw_1^\pm\tz_2 production, we show that LHC14 with 100 fb^{-1} of integrated luminosity becomes sensitive to chargino masses in the range m_{\tw_1}\sim 450-550 GeV corresponding to m_{\tg}\sim 1.5-2 TeV in models with gaugino mass unification. For 10^3 fb^{-1}, LHC14 is sensitive to the Wh channel for m_{\tw_1}\sim 300-800 GeV, corresponding to m_{\tg}\sim 1-2.8 TeV, which is comparable to the reach for gluino pair production followed by cascade decays. The Wh+MET search channel opens up a new complementary avenue for SUSY searches at LHC, and serves to point to SUSY as the origin of any new physics discovered via multijet and multilepton + MET channels.
[ { "created": "Fri, 13 Jan 2012 21:04:22 GMT", "version": "v1" } ]
2013-05-30
[ [ "Baer", "Howard", "" ], [ "Barger", "Vernon", "" ], [ "Lessa", "Andre", "" ], [ "Sreethawong", "Warintorn", "" ], [ "Tata", "Xerxes", "" ] ]
In SUSY models with heavy squarks and gaugino mass unification, the gaugino pair production reaction pp-> \tw_1^\pm\tz_2 dominates gluino pair production for m_{\tg}\agt 1 TeV at LHC with \sqrt{s}=14 TeV (LHC14). For this mass range, the two-body decays \tw_1\to W\tz_1 and \tz_2\to h\tz_1 are expected to dominate the chargino and neutralino branching fractions. By searching for \ell b\bar{b}+MET events from \tw_1^\pm\tz_2 production, we show that LHC14 with 100 fb^{-1} of integrated luminosity becomes sensitive to chargino masses in the range m_{\tw_1}\sim 450-550 GeV corresponding to m_{\tg}\sim 1.5-2 TeV in models with gaugino mass unification. For 10^3 fb^{-1}, LHC14 is sensitive to the Wh channel for m_{\tw_1}\sim 300-800 GeV, corresponding to m_{\tg}\sim 1-2.8 TeV, which is comparable to the reach for gluino pair production followed by cascade decays. The Wh+MET search channel opens up a new complementary avenue for SUSY searches at LHC, and serves to point to SUSY as the origin of any new physics discovered via multijet and multilepton + MET channels.
1612.08206
Mohamed Abu-Shady
E. M. Khokha, M. Abu-Shady, and T. A. Abdel-Karim
Quarkonium Masses in the N-dimensional Space Using the Analytical Exact Iteration Method
7 pages, 3 figures, and 6 tables
International Journal of Theoretical and Applied Mathematics, V. 2, 86-92 (2016)
10.11648/j.ijtam.20160202.19
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The N-dimensional radial Schrodinger equation with an extended Cornell potential is solved. The analytical exact iteration method is applied. The energy eigenvalues are calculated in the N-dimensional space. The charmonium meson, the bottomonium meson and the bc meson masses are calculated in the N-dimensional space. The special cases are obtained from the general case. The study of the effect of dimensionality number is studied. The mean value of the radius and the mean square velocity of charmonium meson, bottomonium meson, and bc meson are calculated. The present results are improved in comparison with other recent studies and are in good agreement with the experimental data. Therefore, the present method with the present potential gives successfully description of heavy quarkonium properties.
[ { "created": "Sat, 24 Dec 2016 17:10:31 GMT", "version": "v1" } ]
2017-01-11
[ [ "Khokha", "E. M.", "" ], [ "Abu-Shady", "M.", "" ], [ "Abdel-Karim", "T. A.", "" ] ]
The N-dimensional radial Schrodinger equation with an extended Cornell potential is solved. The analytical exact iteration method is applied. The energy eigenvalues are calculated in the N-dimensional space. The charmonium meson, the bottomonium meson and the bc meson masses are calculated in the N-dimensional space. The special cases are obtained from the general case. The study of the effect of dimensionality number is studied. The mean value of the radius and the mean square velocity of charmonium meson, bottomonium meson, and bc meson are calculated. The present results are improved in comparison with other recent studies and are in good agreement with the experimental data. Therefore, the present method with the present potential gives successfully description of heavy quarkonium properties.
0904.4485
John Mason
John D. Mason
Gauge Mediation with a small mu term and light squarks
34 pages, 8 figures. References and minor clarifications added. To appear in PRD
Phys.Rev.D80:015026,2009
10.1103/PhysRevD.80.015026
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a solution to the mu problem in the context of Non-Minimal Gauge Mediation with two Singlets and Low-Scale Messengers. This solution reduces tuning associated with the "Little Hierarchy" problem by permitting a naturally small mu term (100-300 GeV) due to small mixing between the Singlets. The smallness of mu also relies crucially on compressing the Gauge Mediated sparticle spectrum resulting in 330-400 GeV squarks. In addition to a small mu term, the theory achieves a Higgs mass > 114.4 GeV through a large Higgs quartic coupling when tanbeta ~ 1.5. The vacua studied are globally stable with all couplings perturbative to the GUT scale. The amount of tuning required to get the correct Electroweak scale is of order 10%, with a similar residual tuning associated with the region of parameter space where the lightest CP-even Higgs mass is above the LEP bound.
[ { "created": "Wed, 29 Apr 2009 16:47:10 GMT", "version": "v1" }, { "created": "Wed, 15 Jul 2009 15:50:05 GMT", "version": "v2" } ]
2010-05-28
[ [ "Mason", "John D.", "" ] ]
We consider a solution to the mu problem in the context of Non-Minimal Gauge Mediation with two Singlets and Low-Scale Messengers. This solution reduces tuning associated with the "Little Hierarchy" problem by permitting a naturally small mu term (100-300 GeV) due to small mixing between the Singlets. The smallness of mu also relies crucially on compressing the Gauge Mediated sparticle spectrum resulting in 330-400 GeV squarks. In addition to a small mu term, the theory achieves a Higgs mass > 114.4 GeV through a large Higgs quartic coupling when tanbeta ~ 1.5. The vacua studied are globally stable with all couplings perturbative to the GUT scale. The amount of tuning required to get the correct Electroweak scale is of order 10%, with a similar residual tuning associated with the region of parameter space where the lightest CP-even Higgs mass is above the LEP bound.
2302.13510
Katsuya Hashino
Tomohiro Abe, Katsuya Hashino
Gravitational waves from first-order phase transition in an electroweakly interacting vector dark matter model
33 pages, 10 figures, 1 table, version accepted by PTEP
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss gravitational waves in an electroweakly interacting vector dark matter model. In the model, the electroweak gauge symmetry is extended to SU(2)$_0 \times$ SU(2)$_1 \times$SU(2)$_2 \times$ U(1)$_Y$ and spontaneously broken into SU(2)$_L \times$ U(1)$_Y$ at TeV scale. The model has an exchange symmetry between SU(2)$_0$ and SU(2)$_2$. This symmetry stabilizes some massive vector bosons associated with the spontaneous symmetry breaking described above, and an electrically neutral one is a dark matter candidate. In the previous study, it was found that the gauge couplings of SU(2)$_0$ and SU(2)$_1$ are relatively large to explain the measured value of the dark matter energy density via the freeze-out mechanism. With the large gauge couplings, the gauge bosons potentially have a sizable effect on the scalar potential. In this paper, we focus on the phase transition of SU(2)$_0 \times$ SU(2)$_1 \times$ SU(2)$_2 \to$ SU(2)$_L$. We calculate the effective potential at finite temperature and find that the phase transition is first-order and strong in a wide range of the parameter space. The strong first-order phase transition generates gravitational waves. We calculate the gravitational wave spectrum and find that it is possible to detect the gravitational waves predicted in the model by future space-based gravitational wave interferometers. We explore the regions of the parameter space probed by the gravitational wave detection. We find that the gravitational wave detection can probe the region where the mass of $h'$, a CP-even scalar in the model, is a few TeV.
[ { "created": "Mon, 27 Feb 2023 04:19:15 GMT", "version": "v1" }, { "created": "Wed, 6 Dec 2023 07:44:13 GMT", "version": "v2" }, { "created": "Thu, 13 Jun 2024 05:55:51 GMT", "version": "v3" } ]
2024-06-14
[ [ "Abe", "Tomohiro", "" ], [ "Hashino", "Katsuya", "" ] ]
We discuss gravitational waves in an electroweakly interacting vector dark matter model. In the model, the electroweak gauge symmetry is extended to SU(2)$_0 \times$ SU(2)$_1 \times$SU(2)$_2 \times$ U(1)$_Y$ and spontaneously broken into SU(2)$_L \times$ U(1)$_Y$ at TeV scale. The model has an exchange symmetry between SU(2)$_0$ and SU(2)$_2$. This symmetry stabilizes some massive vector bosons associated with the spontaneous symmetry breaking described above, and an electrically neutral one is a dark matter candidate. In the previous study, it was found that the gauge couplings of SU(2)$_0$ and SU(2)$_1$ are relatively large to explain the measured value of the dark matter energy density via the freeze-out mechanism. With the large gauge couplings, the gauge bosons potentially have a sizable effect on the scalar potential. In this paper, we focus on the phase transition of SU(2)$_0 \times$ SU(2)$_1 \times$ SU(2)$_2 \to$ SU(2)$_L$. We calculate the effective potential at finite temperature and find that the phase transition is first-order and strong in a wide range of the parameter space. The strong first-order phase transition generates gravitational waves. We calculate the gravitational wave spectrum and find that it is possible to detect the gravitational waves predicted in the model by future space-based gravitational wave interferometers. We explore the regions of the parameter space probed by the gravitational wave detection. We find that the gravitational wave detection can probe the region where the mass of $h'$, a CP-even scalar in the model, is a few TeV.
hep-ph/0302166
Adriano Doff Sotta Gomes
A. Doff, A. A. Natale
The origin of the first and third generation fermion masses in a technicolor scenario
10 pages, 9 figures as eps files, Latex; Abridged version of the previous preprint. Title changed. Results remain the same
Eur.Phys.J.C32:417-426,2003
10.1140/epjc/s2003-01395-9
null
hep-ph
null
We argue that the masses of the first and third fermionic generations, which are respectively of the order of a few MeV up to a hundred GeV, are originated in a dynamical symmetry breaking mechanism leading to masses of the order $\alpha \mu$, where $\alpha$ is a small coupling constant and $\mu$, in the case of the first fermionic generation, is the scale of the dynamical quark mass ($\approx 250$ MeV). For the third fermion generation $\mu$ is the value of the dynamical techniquark mass ($\approx 250$ GeV). We discuss how this possibility can be implemented in a technicolor scenario, and how the mass of the intermediate generation is generated.
[ { "created": "Wed, 19 Feb 2003 02:44:56 GMT", "version": "v1" }, { "created": "Thu, 20 Feb 2003 20:15:18 GMT", "version": "v2" }, { "created": "Wed, 23 Jul 2003 19:43:19 GMT", "version": "v3" }, { "created": "Thu, 22 Jan 2004 20:46:22 GMT", "version": "v4" } ]
2011-09-13
[ [ "Doff", "A.", "" ], [ "Natale", "A. A.", "" ] ]
We argue that the masses of the first and third fermionic generations, which are respectively of the order of a few MeV up to a hundred GeV, are originated in a dynamical symmetry breaking mechanism leading to masses of the order $\alpha \mu$, where $\alpha$ is a small coupling constant and $\mu$, in the case of the first fermionic generation, is the scale of the dynamical quark mass ($\approx 250$ MeV). For the third fermion generation $\mu$ is the value of the dynamical techniquark mass ($\approx 250$ GeV). We discuss how this possibility can be implemented in a technicolor scenario, and how the mass of the intermediate generation is generated.
2109.13321
Pracheta Singha
Chowdhury Aminul Islam, Munshi G. Mustafa, Rajarshi Ray, Pracheta Singha
Consistent approach to study gluon quasi-particles
8 pages, 9 captioned figures, matches with the published version
Phys. Rev. D 106, 054002 (2022)
10.1103/PhysRevD.106.054002
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss a novel approach to estimate the partition function in effective model frameworks when the effective potentials have multiple extrema, so that ascertaining a mean field becomes difficult. Using this approach we present a consistent model to study the thermodynamic properties of gluon quasi-particles as a function of temperature, both in the color confined and the color deconfined phases.
[ { "created": "Mon, 27 Sep 2021 19:47:31 GMT", "version": "v1" }, { "created": "Sun, 12 Mar 2023 19:12:29 GMT", "version": "v2" } ]
2023-03-14
[ [ "Islam", "Chowdhury Aminul", "" ], [ "Mustafa", "Munshi G.", "" ], [ "Ray", "Rajarshi", "" ], [ "Singha", "Pracheta", "" ] ]
We discuss a novel approach to estimate the partition function in effective model frameworks when the effective potentials have multiple extrema, so that ascertaining a mean field becomes difficult. Using this approach we present a consistent model to study the thermodynamic properties of gluon quasi-particles as a function of temperature, both in the color confined and the color deconfined phases.
hep-ph/0011160
Gary Felder
Gary Felder & Lev Kofman
The Development of Equilibrium After Preheating
15 pages, 23 figures
Phys.Rev. D63 (2001) 103503
10.1103/PhysRevD.63.103503
null
hep-ph astro-ph gr-qc hep-lat hep-th nlin.CD
null
We present a fully nonlinear study of the development of equilibrium after preheating. Preheating is the exponentially rapid transfer of energy from the nearly homogeneous inflaton field to fluctuations of other fields and/or the inflaton itself. This rapid transfer leaves these fields in a highly nonthermal state with energy concentrated in infrared modes. We have performed lattice simulations of the evolution of interacting scalar fields during and after preheating for a variety of inflationary models. We have formulated a set of generic rules that govern the thermalization process in all of these models. Notably, we see that once one of the fields is amplified through parametric resonance or other mechanisms it rapidly excites other coupled fields to exponentially large occupation numbers. These fields quickly acquire nearly thermal spectra in the infrared, which gradually propagates into higher momenta. Prior to the formation of total equilibrium, the excited fields group into subsets with almost identical characteristics (e.g. group effective temperature). The way fields form into these groups and the properties of the groups depend on the couplings between them. We also studied the onset of chaos after preheating by calculating the Lyapunov exponent of the scalar fields.
[ { "created": "Mon, 13 Nov 2000 02:51:25 GMT", "version": "v1" }, { "created": "Thu, 1 Feb 2001 21:55:11 GMT", "version": "v2" } ]
2009-10-31
[ [ "Felder", "Gary", "" ], [ "Kofman", "Lev", "" ] ]
We present a fully nonlinear study of the development of equilibrium after preheating. Preheating is the exponentially rapid transfer of energy from the nearly homogeneous inflaton field to fluctuations of other fields and/or the inflaton itself. This rapid transfer leaves these fields in a highly nonthermal state with energy concentrated in infrared modes. We have performed lattice simulations of the evolution of interacting scalar fields during and after preheating for a variety of inflationary models. We have formulated a set of generic rules that govern the thermalization process in all of these models. Notably, we see that once one of the fields is amplified through parametric resonance or other mechanisms it rapidly excites other coupled fields to exponentially large occupation numbers. These fields quickly acquire nearly thermal spectra in the infrared, which gradually propagates into higher momenta. Prior to the formation of total equilibrium, the excited fields group into subsets with almost identical characteristics (e.g. group effective temperature). The way fields form into these groups and the properties of the groups depend on the couplings between them. We also studied the onset of chaos after preheating by calculating the Lyapunov exponent of the scalar fields.
1206.4921
Kanako Yamazaki
Kanako Yamazaki and Tetsuo Matsui
Equation of state of a meson gas from the PNJL model for interacting quarks
6 pages, 3 figures. arXiv admin note: substantial text overlap with arXiv:1212.6165
null
null
UT-Komaba/12-3
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the equation of state of hadronic matter at finite temperature with zero net baryon density by the Nambu-Jona-Lasinio model for interacting quarks in uniform background temporal color gauge fields. In the low temperature confining phase, unphysical thermal quark-antiquark excitations which would appear in the mean field approximation, are eliminated by enforcing vanishing expectation value of the "Polyakov-loop" of the background gauge field, while in the high temperature confining phase this expectation value is taken as close to unity allowing thermal excitations of free quarks and antiquarks. Mesonic excitations in the low temperature phase appear in the correlation energy as contributions of collective excitations. We describe them in terms of thermal fluctuations of auxiliary fields in one-loop (Gaussian) approximation, where pions appear as Nambu-Goldstone modes associated with dynamical symmetry breaking of the chiral symmetry in the limit of vanishing bare quark masses. We show that the equations of state reduces to that of free meson gas with numerically small corrections arising from the composite nature of mesons.
[ { "created": "Thu, 21 Jun 2012 16:02:17 GMT", "version": "v1" }, { "created": "Fri, 18 Jan 2013 09:17:10 GMT", "version": "v2" } ]
2013-01-21
[ [ "Yamazaki", "Kanako", "" ], [ "Matsui", "Tetsuo", "" ] ]
We compute the equation of state of hadronic matter at finite temperature with zero net baryon density by the Nambu-Jona-Lasinio model for interacting quarks in uniform background temporal color gauge fields. In the low temperature confining phase, unphysical thermal quark-antiquark excitations which would appear in the mean field approximation, are eliminated by enforcing vanishing expectation value of the "Polyakov-loop" of the background gauge field, while in the high temperature confining phase this expectation value is taken as close to unity allowing thermal excitations of free quarks and antiquarks. Mesonic excitations in the low temperature phase appear in the correlation energy as contributions of collective excitations. We describe them in terms of thermal fluctuations of auxiliary fields in one-loop (Gaussian) approximation, where pions appear as Nambu-Goldstone modes associated with dynamical symmetry breaking of the chiral symmetry in the limit of vanishing bare quark masses. We show that the equations of state reduces to that of free meson gas with numerically small corrections arising from the composite nature of mesons.
1505.00177
Sudipa Upadhaya
Kinkar Saha, Sudipa Upadhaya and Sabyasachi Ghosh
A comparative study on two different expressions of Bulk viscosity in the PNJL model
13 pages, 4 figures
null
10.1142/S0217732317500183
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have gone through a comparative study on two different kind of bulk viscosity expressions by using a common dynamical model. The Polyakov-Nambu-Jona-Lasinio (PNJL) model in the realm of mean-field approximation, including up to eight quark interactions for 2+1 flavor quark matter, is treated for this common dynamics. We have probed the numerical equivalence as well as discrepancy of two different expressions for bulk viscosity at vanishing quark chemical potential. Our estimation of bulk viscosity to entropy density ratio follows a decreasing trend with temperature, which is observed in most of the earlier investigations. We have also extended our estimation for finite values of quark chemical potential.
[ { "created": "Fri, 1 May 2015 13:40:20 GMT", "version": "v1" }, { "created": "Tue, 29 Nov 2016 09:34:28 GMT", "version": "v2" } ]
2017-01-10
[ [ "Saha", "Kinkar", "" ], [ "Upadhaya", "Sudipa", "" ], [ "Ghosh", "Sabyasachi", "" ] ]
We have gone through a comparative study on two different kind of bulk viscosity expressions by using a common dynamical model. The Polyakov-Nambu-Jona-Lasinio (PNJL) model in the realm of mean-field approximation, including up to eight quark interactions for 2+1 flavor quark matter, is treated for this common dynamics. We have probed the numerical equivalence as well as discrepancy of two different expressions for bulk viscosity at vanishing quark chemical potential. Our estimation of bulk viscosity to entropy density ratio follows a decreasing trend with temperature, which is observed in most of the earlier investigations. We have also extended our estimation for finite values of quark chemical potential.
1310.2793
Subhasis Samanta
Abhijit Bhattacharyya, Supriya Das, Sanjay K. Ghosh, Rajarshi Ray and Subhasis Samanta
Fluctuations and correlations of conserved charges in an excluded volume hadron resonance gas model
15 pages, 13 figures
Phys. Rev. C 90, 034909 (2014)
10.1103/PhysRevC.90.034909
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present temperature ($T$) and baryonic chemical potential ($\mu_B$) dependence of higher order fluctuations and correlation between conserved charges in Excluded Volume Hadron Resonance Gas (EVHRG) model. Products of moments, such as ratio of variance to mean ($\sigma^2/M)$, product of skewness and standard deviation ($S\sigma$), product of kurtosis and variance ($\kappa\sigma^2$), for net-proton, net-kaon and net-charge have been evaluated on the phenomenologically determined freeze-out curve. Further, products of moments for net-proton and net-charge have been compared with the experimental data measured by STAR experiment. The dependence of the model result on the hadronic radius parameter has also been discussed.
[ { "created": "Thu, 10 Oct 2013 12:43:25 GMT", "version": "v1" }, { "created": "Thu, 18 Sep 2014 17:12:40 GMT", "version": "v2" } ]
2015-06-17
[ [ "Bhattacharyya", "Abhijit", "" ], [ "Das", "Supriya", "" ], [ "Ghosh", "Sanjay K.", "" ], [ "Ray", "Rajarshi", "" ], [ "Samanta", "Subhasis", "" ] ]
We present temperature ($T$) and baryonic chemical potential ($\mu_B$) dependence of higher order fluctuations and correlation between conserved charges in Excluded Volume Hadron Resonance Gas (EVHRG) model. Products of moments, such as ratio of variance to mean ($\sigma^2/M)$, product of skewness and standard deviation ($S\sigma$), product of kurtosis and variance ($\kappa\sigma^2$), for net-proton, net-kaon and net-charge have been evaluated on the phenomenologically determined freeze-out curve. Further, products of moments for net-proton and net-charge have been compared with the experimental data measured by STAR experiment. The dependence of the model result on the hadronic radius parameter has also been discussed.
hep-ph/0109019
Vittorio Del Duca
J.R. Andersen, V. Del Duca, S. Frixione, F. Maltoni, C.R. Schmidt and W.J. Stirling
Forward jets and forward $W$-boson production at hadron colliders
LaTeX, JHEP style, 10 pages, 3 figures. Based on a talk at EPS2001, Budapest, Hungary
null
null
null
hep-ph
null
In this talk we give a short review of forward jets and forward $W$-boson production at hadron colliders, in view of the extraction of footprints of BFKL physics. We argue that at Tevatron energies, dijet production at large rapidity intervals is still subasymptotic with respect to the BFKL regime, thus the cross section is strongly dependent on the various cuts applied in the experimental setup. In addition, the choice of equal transverse momentum cuts on the tagging jets makes the cross section dependent on large logarithms of non-BFKL origin, and thus may spoil the BFKL analysis. For vector boson production in association with two jets, we argue that the configurations that are kinematically favoured tend to have the vector boson forward in rapidity. Thus $W + 2$ jet production lends itself naturally to extensions to the high-energy limit.
[ { "created": "Mon, 3 Sep 2001 13:50:26 GMT", "version": "v1" } ]
2007-05-23
[ [ "Andersen", "J. R.", "" ], [ "Del Duca", "V.", "" ], [ "Frixione", "S.", "" ], [ "Maltoni", "F.", "" ], [ "Schmidt", "C. R.", "" ], [ "Stirling", "W. J.", "" ] ]
In this talk we give a short review of forward jets and forward $W$-boson production at hadron colliders, in view of the extraction of footprints of BFKL physics. We argue that at Tevatron energies, dijet production at large rapidity intervals is still subasymptotic with respect to the BFKL regime, thus the cross section is strongly dependent on the various cuts applied in the experimental setup. In addition, the choice of equal transverse momentum cuts on the tagging jets makes the cross section dependent on large logarithms of non-BFKL origin, and thus may spoil the BFKL analysis. For vector boson production in association with two jets, we argue that the configurations that are kinematically favoured tend to have the vector boson forward in rapidity. Thus $W + 2$ jet production lends itself naturally to extensions to the high-energy limit.
1111.5292
Ricardo Torres Andres
R. Torres Andres, A. Gomez Nicola
Scalar susceptibilities and Electromagnetic thermal mass differences in Chiral Perturbation Theory
Proceedings of the "International School of Nuclear Physics", Erice, Italy, September 16th-September 24th 2011. 7 pages, 5 figures. To be published in Prog. Part. Nucl. Phys
null
10.1016/j.ppnp.2011.12.040
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We make a thermal analysis of the light scalar susceptibilities using SU(3)-Chiral Perturbation Theory to one loop taking into account the QCD source of isospin breaking (IB), i.e corrections coming from $m_u\neq m_d$. The value of the connected scalar susceptibility in the infrared regime, the one relevant when approaching chiral symmetry restoration, and below the critical temperature is found to be entirely dominated by the $\pi^0-\eta$ mixing, which leads to model-independent $\mathcal{O}(\epsilon^0)$ corrections, where $\epsilon\sim m_d-m_u$, in the combination $\chi_{uu}-\chi_{ud}$ of flavour breaking susceptibilities. We also present preliminary results for the corrections to the real part of the pion self-energy at nexst-to-leading order in SU(2)-Chiral Perturbation Theory taking into account electromagnetic interaction. The zero and finite temperature results for the charged and neutral pions are given in terms of the three-momentum of the external pion; and their difference is calculated to this order stressing the fact that, at low and moderate temperature, the mass splitting $M_{\pi^\pm}-M_{\pi^0}$ grows with temperature for, at least, non-zero charged pion mass running inside the loops.
[ { "created": "Tue, 22 Nov 2011 19:24:29 GMT", "version": "v1" }, { "created": "Wed, 23 Nov 2011 11:02:18 GMT", "version": "v2" } ]
2015-06-03
[ [ "Andres", "R. Torres", "" ], [ "Nicola", "A. Gomez", "" ] ]
We make a thermal analysis of the light scalar susceptibilities using SU(3)-Chiral Perturbation Theory to one loop taking into account the QCD source of isospin breaking (IB), i.e corrections coming from $m_u\neq m_d$. The value of the connected scalar susceptibility in the infrared regime, the one relevant when approaching chiral symmetry restoration, and below the critical temperature is found to be entirely dominated by the $\pi^0-\eta$ mixing, which leads to model-independent $\mathcal{O}(\epsilon^0)$ corrections, where $\epsilon\sim m_d-m_u$, in the combination $\chi_{uu}-\chi_{ud}$ of flavour breaking susceptibilities. We also present preliminary results for the corrections to the real part of the pion self-energy at nexst-to-leading order in SU(2)-Chiral Perturbation Theory taking into account electromagnetic interaction. The zero and finite temperature results for the charged and neutral pions are given in terms of the three-momentum of the external pion; and their difference is calculated to this order stressing the fact that, at low and moderate temperature, the mass splitting $M_{\pi^\pm}-M_{\pi^0}$ grows with temperature for, at least, non-zero charged pion mass running inside the loops.
1807.10606
Alexei Prokudin
S. Bastami, H. Avakian, A. V. Efremov, A. Kotzinian, B. U. Musch, B. Parsamyan, A. Prokudin, M. Schlegel, G. Schnell, P. Schweitzer, K. Tezgin
Semi-Inclusive Deep Inelastic Scattering in Wandzura-Wilczek-type approximation
Published in JHEP, 71 pages, 21 figures, references updated, discussion improved
JHEP 06 (2019) 007
10.1007/JHEP06(2019)007
JLAB-THY-18-2775
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the complete cross-section for the production of unpolarized hadrons in semi-inclusive deep-inelastic scattering up to power-suppressed ${\cal O}(1/Q^2)$ terms in the Wandzura--Wilczek-type approximation which consists in systematically assuming that $\bar{q}gq$--terms are much smaller than $\bar{q}q$--correlators. We compute all twist-2 and twist-3 structure functions and the corresponding asymmetries, and discuss the applicability of the Wandzura--Wilczek-type approximations on the basis of available data. We make predictions that can be tested by data from Jefferson Lab, COMPASS, HERMES, and the future Electron-Ion Collider. The results of this paper can be readily used for phenomenology and for event generators, and will help to improve our understanding of the TMD theory beyond leading twist.
[ { "created": "Fri, 27 Jul 2018 13:24:30 GMT", "version": "v1" }, { "created": "Mon, 14 Jan 2019 18:35:31 GMT", "version": "v2" }, { "created": "Mon, 10 Jun 2019 15:46:16 GMT", "version": "v3" } ]
2019-06-18
[ [ "Bastami", "S.", "" ], [ "Avakian", "H.", "" ], [ "Efremov", "A. V.", "" ], [ "Kotzinian", "A.", "" ], [ "Musch", "B. U.", "" ], [ "Parsamyan", "B.", "" ], [ "Prokudin", "A.", "" ], [ "Schlegel", "M.", "" ], [ "Schnell", "G.", "" ], [ "Schweitzer", "P.", "" ], [ "Tezgin", "K.", "" ] ]
We present the complete cross-section for the production of unpolarized hadrons in semi-inclusive deep-inelastic scattering up to power-suppressed ${\cal O}(1/Q^2)$ terms in the Wandzura--Wilczek-type approximation which consists in systematically assuming that $\bar{q}gq$--terms are much smaller than $\bar{q}q$--correlators. We compute all twist-2 and twist-3 structure functions and the corresponding asymmetries, and discuss the applicability of the Wandzura--Wilczek-type approximations on the basis of available data. We make predictions that can be tested by data from Jefferson Lab, COMPASS, HERMES, and the future Electron-Ion Collider. The results of this paper can be readily used for phenomenology and for event generators, and will help to improve our understanding of the TMD theory beyond leading twist.
hep-ph/0603107
Pasquale Di Bari
Steve Blanchet and Pasquale Di Bari
Leptogenesis beyond the limit of hierarchical heavy neutrino masses
30 pages, 8 figures; corrected typo in Eq. (67); shortened Introduction, Section 3 and Conclusions; one figure removed; added 2 references; to appear in JCAP
JCAP 0606:023,2006
10.1088/1475-7516/2006/06/023
MPP-2006-20
hep-ph
null
We calculate the baryon asymmetry of the Universe in thermal leptogenesis beyond the usual lightest right-handed (RH) neutrino dominated scenario (N_1DS) and in particular beyond the hierarchical limit (HL), M_1 << M_2 << M_3, for the RH neutrino mass spectrum. After providing some orientation among the large variety of models, we first revisit the central role of the N_1DS, with new insights on the dynamics of the asymmetry generation and then discuss the main routes departing from it, focusing on models beyond the HL. We study in detail two examples of `strong-strong' wash-out scenarios: one with `maximal phase' and the limit of very large M_3, studying the effects arising when delta_2=(M_2-M_1)/M_1 is small. We extend analytical methods already applied to the N_1DS showing, for example, that, in the degenerate limit (DL), the efficiency factors of the RH neutrinos become equal with the single decay parameter replaced by the sum. Both cases disprove the misconception that close RH neutrino masses necessarily lead to a final asymmetry enhancement and to a relaxation of the lower bounds on M_1 and on the initial temperature of the radiation-dominated expansion. We also explain why leptogenesis tends to favor normal hierarchy compared to inverted hierarchy for the left-handed neutrino masses.
[ { "created": "Wed, 15 Mar 2006 18:57:26 GMT", "version": "v1" }, { "created": "Fri, 2 Jun 2006 10:07:34 GMT", "version": "v2" } ]
2011-07-19
[ [ "Blanchet", "Steve", "" ], [ "Di Bari", "Pasquale", "" ] ]
We calculate the baryon asymmetry of the Universe in thermal leptogenesis beyond the usual lightest right-handed (RH) neutrino dominated scenario (N_1DS) and in particular beyond the hierarchical limit (HL), M_1 << M_2 << M_3, for the RH neutrino mass spectrum. After providing some orientation among the large variety of models, we first revisit the central role of the N_1DS, with new insights on the dynamics of the asymmetry generation and then discuss the main routes departing from it, focusing on models beyond the HL. We study in detail two examples of `strong-strong' wash-out scenarios: one with `maximal phase' and the limit of very large M_3, studying the effects arising when delta_2=(M_2-M_1)/M_1 is small. We extend analytical methods already applied to the N_1DS showing, for example, that, in the degenerate limit (DL), the efficiency factors of the RH neutrinos become equal with the single decay parameter replaced by the sum. Both cases disprove the misconception that close RH neutrino masses necessarily lead to a final asymmetry enhancement and to a relaxation of the lower bounds on M_1 and on the initial temperature of the radiation-dominated expansion. We also explain why leptogenesis tends to favor normal hierarchy compared to inverted hierarchy for the left-handed neutrino masses.
1011.4905
Peihong Gu
Pei-Hong Gu, Manfred Lindner
Natural Inflation and Flavor Mixing from Peccei-Quinn Symmetry Breaking
4 pages, 2 figures
Phys.Lett.B697:229-232,2011
10.1016/j.physletb.2011.02.005
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a left-right symmetric model to simultaneously give natural inflation and flavor mixing from a Peccei-Quinn symmetry breaking at the Planck scale. Our model can be embedded in SO(10) grand unification theories.
[ { "created": "Mon, 22 Nov 2010 18:45:52 GMT", "version": "v1" } ]
2011-05-26
[ [ "Gu", "Pei-Hong", "" ], [ "Lindner", "Manfred", "" ] ]
We propose a left-right symmetric model to simultaneously give natural inflation and flavor mixing from a Peccei-Quinn symmetry breaking at the Planck scale. Our model can be embedded in SO(10) grand unification theories.
2007.08300
Ignacio Borsa Sanjuan
Elke C. Aschenauer, Ignacio Borsa, Gonzalo Lucero, Ana S. Nunes, Rodolfo Sassot
Revisiting Helicity Parton Distributions at a Future Electron-Ion Collider
19 pages, 19 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We studied the impact of future Electron Ion Collider inclusive and semi-inclusive polarized deep inelastic scattering data will have on the determination of the helicity parton distributions. Supplementing the Monte Carlo sampling variant of the DSSV14 analysis with pseudo-data on polarized inclusive and semi-inclusive electron-proton deep inelastic scattering with updated uncertainty estimates and for two different center-of-mass-system energies, $\sqrt{s}=44.7$ GeV and $\sqrt{s}=141.4$ GeV respectively, and on inclusive electron-helium collisions at $\sqrt{s}=115.2$ GeV, we find a remarkable improvement in the determination of the helicity distributions, specially at low parton momentum fraction $x$. While inclusive electron-proton data at the lowest energy configuration constrain significantly the gluon polarization down to $x \sim 10^{-4}$, the higher energy configuration strengthens the constraint and extends it one decade further. On the other hand, semi-inclusive data achieves the hitherto elusive flavor separation for sea quarks that can not be obtained from any other inclusive electromagnetic measurement. Collisions with helium complement inclusive proton measurements, pushing the constraints on the combined quark plus anti-quark $u, d$ and $s$ polarizations to an unprecedented level.
[ { "created": "Thu, 16 Jul 2020 12:38:39 GMT", "version": "v1" } ]
2020-07-17
[ [ "Aschenauer", "Elke C.", "" ], [ "Borsa", "Ignacio", "" ], [ "Lucero", "Gonzalo", "" ], [ "Nunes", "Ana S.", "" ], [ "Sassot", "Rodolfo", "" ] ]
We studied the impact of future Electron Ion Collider inclusive and semi-inclusive polarized deep inelastic scattering data will have on the determination of the helicity parton distributions. Supplementing the Monte Carlo sampling variant of the DSSV14 analysis with pseudo-data on polarized inclusive and semi-inclusive electron-proton deep inelastic scattering with updated uncertainty estimates and for two different center-of-mass-system energies, $\sqrt{s}=44.7$ GeV and $\sqrt{s}=141.4$ GeV respectively, and on inclusive electron-helium collisions at $\sqrt{s}=115.2$ GeV, we find a remarkable improvement in the determination of the helicity distributions, specially at low parton momentum fraction $x$. While inclusive electron-proton data at the lowest energy configuration constrain significantly the gluon polarization down to $x \sim 10^{-4}$, the higher energy configuration strengthens the constraint and extends it one decade further. On the other hand, semi-inclusive data achieves the hitherto elusive flavor separation for sea quarks that can not be obtained from any other inclusive electromagnetic measurement. Collisions with helium complement inclusive proton measurements, pushing the constraints on the combined quark plus anti-quark $u, d$ and $s$ polarizations to an unprecedented level.
hep-ph/0306122
Gilberto Colangelo
I. Caprini, G. Colangelo, J. Gasser and H. Leutwyler
On the precision of the theoretical predictions for pi pi scattering
Added more material, mostly in Sects. 7, 8 and 9, in support of the same conclusions. Latex, 28 pages, 3 figures
Phys.Rev. D68 (2003) 074006
10.1103/PhysRevD.68.074006
null
hep-ph
null
In a recent paper, Pelaez and Yndurain evaluate some of the low energy observables of pi pi scattering and obtain flat disagreement with our earlier results. The authors work with unsubtracted dispersion relations, so that their results are very sensitive to the poorly known high energy behaviour of the scattering amplitude. They claim that the asymptotic representation we used is incorrect and propose an alternative one. We repeat their calculations on the basis of the standard, subtracted fixed-t dispersion relations, using their asymptotics. The outcome fully confirms our earlier findings. Moreover, we show that the Regge parametrization proposed by these authors for the region above 1.4 GeV violates crossing symmetry: Their ansatz is not consistent with the behaviour observed at low energies.
[ { "created": "Fri, 13 Jun 2003 14:16:53 GMT", "version": "v1" }, { "created": "Tue, 26 Aug 2003 16:46:51 GMT", "version": "v2" } ]
2009-11-10
[ [ "Caprini", "I.", "" ], [ "Colangelo", "G.", "" ], [ "Gasser", "J.", "" ], [ "Leutwyler", "H.", "" ] ]
In a recent paper, Pelaez and Yndurain evaluate some of the low energy observables of pi pi scattering and obtain flat disagreement with our earlier results. The authors work with unsubtracted dispersion relations, so that their results are very sensitive to the poorly known high energy behaviour of the scattering amplitude. They claim that the asymptotic representation we used is incorrect and propose an alternative one. We repeat their calculations on the basis of the standard, subtracted fixed-t dispersion relations, using their asymptotics. The outcome fully confirms our earlier findings. Moreover, we show that the Regge parametrization proposed by these authors for the region above 1.4 GeV violates crossing symmetry: Their ansatz is not consistent with the behaviour observed at low energies.
hep-ph/0204034
Kari J. Eskola
K.J. Eskola, K. Kajantie, P.V. Ruuskanen, K. Tuominen
Rapidity dependence of particle production in ultrarelativistic nuclear collisions
12 pages, 8 eps-figures
Phys.Lett.B543:208-216,2002
10.1016/S0370-2693(02)02457-7
HIP-2002-10/TH, NORDITA-2002-20-HE
hep-ph nucl-th
null
We compute the rapidity dependence of particle and transverse energy production in ultrarelativistic heavy ion collisions at various beam energies and atomic numbers using the perturbative QCD + saturation model. The distribution is a broad gaussian near $y=0$ but the rapid increase of particle production with the beam energy will via energy conservation strongly constrain the rapidity distribution at large $y$.
[ { "created": "Wed, 3 Apr 2002 10:23:26 GMT", "version": "v1" } ]
2014-11-17
[ [ "Eskola", "K. J.", "" ], [ "Kajantie", "K.", "" ], [ "Ruuskanen", "P. V.", "" ], [ "Tuominen", "K.", "" ] ]
We compute the rapidity dependence of particle and transverse energy production in ultrarelativistic heavy ion collisions at various beam energies and atomic numbers using the perturbative QCD + saturation model. The distribution is a broad gaussian near $y=0$ but the rapid increase of particle production with the beam energy will via energy conservation strongly constrain the rapidity distribution at large $y$.
2002.06411
Yayun He
Y. He (1), S. Cao (2), W. Chen (1), T. Luo (1), L.-G. Pang (3 and 4) and X.-N. Wang (1, 3 and 4) ((1) Central China Normal University, (2) Wayne State University, (3) University of California, Berkeley, (4) Lawrence Berkeley National Laboratory)
Interplaying mechanisms behind inclusive jet $R_{AA}$ and extraction of jet energy loss distributions
4 pages, 3 figures, contribution to the proceedings of XXVIIIth International Conference on Ultrarelativistic Nucleus-Nucleus Collisions (Quark Matter 2019)
null
10.1016/j.nuclphysa.2020.122032
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The observed inclusive jet suppression in heavy-ion collisions at LHC has a very weak $p_{T}$ dependence over a large range of $p_{T}$ = 50-1000 GeV and is almost independent of the colliding energy, though the initial energy density of the bulk medium has increased from $\sqrt{s}$ = 2.76 to 5.02 TeV by about 20%. This interesting phenomenon is investigated in the linear Boltzmann transport (LBT) model for jet propagation in an event-by-event 3+1D hydro background. We show that the $p_{T}$ dependence of jet $R_{AA}$ is determined by the initial spectrum in $p+p$ collisions and $ p_{T} $ dependence of jet energy loss. Furthermore, jet energy loss distributions for inclusive jet and $ \gamma-$jet at both LHC energies are extracted directly from experimental data through the state-of-art Bayesian analysis. The averaged jet energy loss has a weak $p_{T}$ dependence and the scaled jet energy loss distributions have a large width, both of which are consistent with the LBT simulations and indicate that jet quenching is caused by only a few out-of-cone jet medium scatterings.
[ { "created": "Sat, 15 Feb 2020 16:49:11 GMT", "version": "v1" }, { "created": "Mon, 3 Aug 2020 09:24:58 GMT", "version": "v2" } ]
2021-02-03
[ [ "He", "Y.", "", "3 and 4" ], [ "Cao", "S.", "", "3 and 4" ], [ "Chen", "W.", "", "3 and 4" ], [ "Luo", "T.", "", "3 and 4" ], [ "Pang", "L. -G.", "", "3 and 4" ], [ "Wang", "X. -N.", "", "1, 3 and 4" ] ]
The observed inclusive jet suppression in heavy-ion collisions at LHC has a very weak $p_{T}$ dependence over a large range of $p_{T}$ = 50-1000 GeV and is almost independent of the colliding energy, though the initial energy density of the bulk medium has increased from $\sqrt{s}$ = 2.76 to 5.02 TeV by about 20%. This interesting phenomenon is investigated in the linear Boltzmann transport (LBT) model for jet propagation in an event-by-event 3+1D hydro background. We show that the $p_{T}$ dependence of jet $R_{AA}$ is determined by the initial spectrum in $p+p$ collisions and $ p_{T} $ dependence of jet energy loss. Furthermore, jet energy loss distributions for inclusive jet and $ \gamma-$jet at both LHC energies are extracted directly from experimental data through the state-of-art Bayesian analysis. The averaged jet energy loss has a weak $p_{T}$ dependence and the scaled jet energy loss distributions have a large width, both of which are consistent with the LBT simulations and indicate that jet quenching is caused by only a few out-of-cone jet medium scatterings.
0710.2817
Thomas Schutzmeier
Thomas Schutzmeier
Progress in the evaluation of the anti-B -> X_s gamma decay rate at NNLO
Presented at the XXXI International Conference of Theoretical Physics "Matter To The Deepest: Recent Developments In Physics of Fundamental Interactions", Ustron, 5-11 September 2007, Poland; 5 pages
Acta Phys.Polon.B38:3537-3542,2007
null
null
hep-ph
null
The theoretical status of NNLO QCD corrections to the inclusive radiative anti-B -> X_s gamma decay in the standard model is briefly overviewed. Emphasis is put on recent results for three-loop fermionic corrections to matrix elements of the most relevant four-quark operators.
[ { "created": "Mon, 15 Oct 2007 13:47:36 GMT", "version": "v1" } ]
2008-12-30
[ [ "Schutzmeier", "Thomas", "" ] ]
The theoretical status of NNLO QCD corrections to the inclusive radiative anti-B -> X_s gamma decay in the standard model is briefly overviewed. Emphasis is put on recent results for three-loop fermionic corrections to matrix elements of the most relevant four-quark operators.
2003.05450
Xing Wang
Anadi Canepa, Tao Han, Xing Wang
The Search for Electroweakinos
33 pages, 13 figures. Invited review prepared for publication in the Annual Review of Nuclear and Particle Science, Volume 70 (2020)
null
10.1146/annurev-nucl-031020-121031
FERMILAB-PUB-16-565-T; PITT-PACC-2001
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this review, we consider a general theoretical framework for fermionic color-singlet states, including a singlet, a doublet and a triplet under the standard model SU(2)$_{\rm L}$ gauge symmetry, corresponding to the Bino, Higgsino and Wino in Supersymmetric theories, generically dubbed as "electroweakinos" for their mass eigenstates. Depending on the relations among their three mass parameters and the mixings after the electroweak symmetry breaking, this sector leads to rich phenomenology potentially accessible at the current and near-future experiments. We discuss the decay patterns of the electroweakinos and their observable signatures at colliders. We review the existing bounds on the model parameters. We summarize the current status for the comprehensive searches from the ATLAS and CMS experiments at the LHC. We comment on the prospects for future colliders. An important feature of the theory is that the lightest neutral electroweakino can be identified as a WIMP cold dark matter candidate. We take into account the existing bounds on the parameters from the dark matter direct detection experiments and discuss the complementarity for the electroweakino searches at colliders.
[ { "created": "Wed, 11 Mar 2020 18:00:00 GMT", "version": "v1" } ]
2020-03-13
[ [ "Canepa", "Anadi", "" ], [ "Han", "Tao", "" ], [ "Wang", "Xing", "" ] ]
In this review, we consider a general theoretical framework for fermionic color-singlet states, including a singlet, a doublet and a triplet under the standard model SU(2)$_{\rm L}$ gauge symmetry, corresponding to the Bino, Higgsino and Wino in Supersymmetric theories, generically dubbed as "electroweakinos" for their mass eigenstates. Depending on the relations among their three mass parameters and the mixings after the electroweak symmetry breaking, this sector leads to rich phenomenology potentially accessible at the current and near-future experiments. We discuss the decay patterns of the electroweakinos and their observable signatures at colliders. We review the existing bounds on the model parameters. We summarize the current status for the comprehensive searches from the ATLAS and CMS experiments at the LHC. We comment on the prospects for future colliders. An important feature of the theory is that the lightest neutral electroweakino can be identified as a WIMP cold dark matter candidate. We take into account the existing bounds on the parameters from the dark matter direct detection experiments and discuss the complementarity for the electroweakino searches at colliders.
hep-ph/0211232
Philip G. Ratcliffe
Philip G. Ratcliffe
Single-Spin Asymmetries and Transversity
10 pages, 11 figures, presented at the XV International Symposium on High-Energy Spin Physics (Brookhaven, 9-14 Aug. 2002)
null
10.1063/1.1607129
null
hep-ph
null
A pedagogical introduction to single-spin asymmetries (SSA's) and transversity is presented. Discussion in some detail is made of certain aspects of (SSA's) in lepton-nucleon and in hadron-hadron scattering and the role of pQCD and evolution in the context of transversity.
[ { "created": "Thu, 14 Nov 2002 23:22:32 GMT", "version": "v1" } ]
2009-11-07
[ [ "Ratcliffe", "Philip G.", "" ] ]
A pedagogical introduction to single-spin asymmetries (SSA's) and transversity is presented. Discussion in some detail is made of certain aspects of (SSA's) in lepton-nucleon and in hadron-hadron scattering and the role of pQCD and evolution in the context of transversity.
1011.1646
Pomita Ghoshal
Pomita Ghoshal, S.T.Petcov
Neutrino Mass Hierarchy Determination Using Reactor Antineutrinos
32 pages, 27 figures, accepted in Journal of High Energy Physics
JHEP 1103:058,2011
10.1007/JHEP03(2011)058
Ref. SISSA 77/2010/EP
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Building on earlier studies, we investigate the possibility to determine the type of neutrino mass spectrum (i.e., "the neutrino mass hierarchy") in a high statistics reactor electron antineutrino experiment with a relatively large KamLAND-like detector and an optimal baseline of 60 Km. We analyze systematically the Fourier Sine and Cosine Transforms (FST and FCT) of simulated reactor antineutrino data with reference to their specific mass hierarchy-dependent features discussed earlier in the literature. We perform also a binned \chi^2 analysis of the sensitivity of simulated reactor electron antineutrino event spectrum data to the neutrino mass hierarchy, and determine, in particular, the characteristics of the detector and the experiment (energy resolution, visible energy threshold, exposure, systematic errors, binning of data, etc.), which would allow us to get significant information on, or even determine, the type of the neutrino mass spectrum. We find that if \sin^2 2\theta_{13} is sufficiently large, \sin^2 2\theta_{13} \gtap 0.02, the requirements on the set-up of interest are very challenging, but not impossible to realize.
[ { "created": "Sun, 7 Nov 2010 15:48:20 GMT", "version": "v1" }, { "created": "Thu, 3 Mar 2011 16:45:43 GMT", "version": "v2" } ]
2011-03-28
[ [ "Ghoshal", "Pomita", "" ], [ "Petcov", "S. T.", "" ] ]
Building on earlier studies, we investigate the possibility to determine the type of neutrino mass spectrum (i.e., "the neutrino mass hierarchy") in a high statistics reactor electron antineutrino experiment with a relatively large KamLAND-like detector and an optimal baseline of 60 Km. We analyze systematically the Fourier Sine and Cosine Transforms (FST and FCT) of simulated reactor antineutrino data with reference to their specific mass hierarchy-dependent features discussed earlier in the literature. We perform also a binned \chi^2 analysis of the sensitivity of simulated reactor electron antineutrino event spectrum data to the neutrino mass hierarchy, and determine, in particular, the characteristics of the detector and the experiment (energy resolution, visible energy threshold, exposure, systematic errors, binning of data, etc.), which would allow us to get significant information on, or even determine, the type of the neutrino mass spectrum. We find that if \sin^2 2\theta_{13} is sufficiently large, \sin^2 2\theta_{13} \gtap 0.02, the requirements on the set-up of interest are very challenging, but not impossible to realize.
hep-ph/0610224
Conrado Albertus-Torres
C. Albertus, J. M. Flynn, E. Hernandez, J. Nieves, J. M. Verde--Velasco
Quark model study of the semileptonic B -> pi decay
Three pages, two figures. To appear in the proceedings of Quark Confinament and Hadron Spectrum VII. Azores, September 2006
AIPConf.Proc.892:312-314,2007
10.1063/1.2714403
SHEP 0633
hep-ph
null
The semileptonic decay B->pi is studied starting from a simple quark model and taking into account the effect of the B* resonance. A novel, multiply subtracted, Omn\`es dispersion relation has been implemented to extend the predictions of the quark model to all physical q^2 values. We find |V_{ub}|=0.0034 +/- 0.0003(exp.)+/- 0.0007(theory), in good agreement with experiment.
[ { "created": "Wed, 18 Oct 2006 09:27:56 GMT", "version": "v1" } ]
2008-11-26
[ [ "Albertus", "C.", "" ], [ "Flynn", "J. M.", "" ], [ "Hernandez", "E.", "" ], [ "Nieves", "J.", "" ], [ "Verde--Velasco", "J. M.", "" ] ]
The semileptonic decay B->pi is studied starting from a simple quark model and taking into account the effect of the B* resonance. A novel, multiply subtracted, Omn\`es dispersion relation has been implemented to extend the predictions of the quark model to all physical q^2 values. We find |V_{ub}|=0.0034 +/- 0.0003(exp.)+/- 0.0007(theory), in good agreement with experiment.
hep-ph/0103060
Nestor Armesto Perez
N. S. Amelin, N. Armesto, C. Pajares and D. Sousa
Monte Carlo model for nuclear collisions from SPS to LHC energies
LaTeX, 48 pages, 6 tables, 15 postscript figures included using epsfig
Eur.Phys.J.C22:149-163,2001
10.1007/s100520100761
UCOFIS 1/01, US-FT/2-01, LPT Orsay 01-15
hep-ph nucl-th
null
A Monte Carlo model to simulate nuclear collisions in the energy range going from SPS to LHC, is presented. The model includes in its initial stage both soft and semihard components, which lead to the formation of color strings. Collectivity is taken into account considering the possibility of strings in color representations higher than triplet or antitriplet, by means of string fusion. String breaking leads to the production of secondaries. At this point, the model can be used as initial condition for further evolution by a transport model. In order to tune the parameters and see the results in nucleus-nucleus collisions, a naif model for rescattering of secondaries is introduced. Results of the model are compared with experimental data, and predictions for RHIC and LHC are shown.
[ { "created": "Tue, 6 Mar 2001 16:40:26 GMT", "version": "v1" } ]
2016-09-06
[ [ "Amelin", "N. S.", "" ], [ "Armesto", "N.", "" ], [ "Pajares", "C.", "" ], [ "Sousa", "D.", "" ] ]
A Monte Carlo model to simulate nuclear collisions in the energy range going from SPS to LHC, is presented. The model includes in its initial stage both soft and semihard components, which lead to the formation of color strings. Collectivity is taken into account considering the possibility of strings in color representations higher than triplet or antitriplet, by means of string fusion. String breaking leads to the production of secondaries. At this point, the model can be used as initial condition for further evolution by a transport model. In order to tune the parameters and see the results in nucleus-nucleus collisions, a naif model for rescattering of secondaries is introduced. Results of the model are compared with experimental data, and predictions for RHIC and LHC are shown.
1211.2130
Ilkka Helenius
Ilkka Helenius, Kari J. Eskola, Heli Honkanen and Carlos A. Salgado
EPS09s and EKS98s: Impact parameter dependent nPDF sets
4 pages, 4 figures, Contribution to the proceedings of the Quark Matter 2012, Washington D.C., August 12-18, 2012
null
10.1016/j.nuclphysa.2013.02.183
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In our recent study we have determined two new spatially dependent nuclear PDF (nPDF) sets, EPS09s and EKS98s. With these, the hard-process cross-sections can be calculated in different centrality classes consistently with the globally analyzed nPDFs for the first time. The sets were determined by exploiting the $A$-systematics of the globally fitted nPDF sets, EPS09 and EKS98. For the spatial dependence of the nPDFs we used a power series ansatz in the nuclear thickness function $T_A$. In this flash talk we introduce the framework, and present our NLO EPS09s-based predictions for the nuclear modification factor in four centrality classes for inclusive neutral pion production in p+Pb collisions at the LHC and for inclusive prompt photon production in d+Au collisions at RHIC at midrapidity.
[ { "created": "Fri, 9 Nov 2012 13:40:57 GMT", "version": "v1" } ]
2015-06-12
[ [ "Helenius", "Ilkka", "" ], [ "Eskola", "Kari J.", "" ], [ "Honkanen", "Heli", "" ], [ "Salgado", "Carlos A.", "" ] ]
In our recent study we have determined two new spatially dependent nuclear PDF (nPDF) sets, EPS09s and EKS98s. With these, the hard-process cross-sections can be calculated in different centrality classes consistently with the globally analyzed nPDFs for the first time. The sets were determined by exploiting the $A$-systematics of the globally fitted nPDF sets, EPS09 and EKS98. For the spatial dependence of the nPDFs we used a power series ansatz in the nuclear thickness function $T_A$. In this flash talk we introduce the framework, and present our NLO EPS09s-based predictions for the nuclear modification factor in four centrality classes for inclusive neutral pion production in p+Pb collisions at the LHC and for inclusive prompt photon production in d+Au collisions at RHIC at midrapidity.
0912.1566
Richard F. Lebed
Thomas D. Cohen, Daniel L. Shafer, Richard F. Lebed
Baryons in QCD_{AS} at Large N_c: A Roundabout Approach
9 pages, 9 pdf figures, ReVTeX with pdflatex
Phys.Rev.D81:036006,2010
10.1103/PhysRevD.81.036006
DOE-40762-475, INT-PUB-09-061
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
QCD_{AS}, a variant of large N_c QCD in which quarks transform under the color two-index antisymmetric representation, reduces to standard QCD at N_c = 3 and provides an alternative to the usual large N_c extrapolation that uses fundamental representation quarks. Previous strong plausibility arguments assert that the QCD_{AS} baryon mass scales as N_c^2; however, the complicated combinatoric problem associated with quarks carrying two color indices impeded a complete demonstration. We develop a diagrammatic technique to solve this problem. The key ingredient is the introduction of an effective multi-gluon vertex: a "traffic circle" or "roundabout" diagram. We show that arbitrarily complicated diagrams can be reduced to simple ones with the same leading N_c scaling using this device, and that the leading contribution to baryon mass does, in fact, scale as N_c^2.
[ { "created": "Tue, 8 Dec 2009 18:49:32 GMT", "version": "v1" } ]
2014-11-20
[ [ "Cohen", "Thomas D.", "" ], [ "Shafer", "Daniel L.", "" ], [ "Lebed", "Richard F.", "" ] ]
QCD_{AS}, a variant of large N_c QCD in which quarks transform under the color two-index antisymmetric representation, reduces to standard QCD at N_c = 3 and provides an alternative to the usual large N_c extrapolation that uses fundamental representation quarks. Previous strong plausibility arguments assert that the QCD_{AS} baryon mass scales as N_c^2; however, the complicated combinatoric problem associated with quarks carrying two color indices impeded a complete demonstration. We develop a diagrammatic technique to solve this problem. The key ingredient is the introduction of an effective multi-gluon vertex: a "traffic circle" or "roundabout" diagram. We show that arbitrarily complicated diagrams can be reduced to simple ones with the same leading N_c scaling using this device, and that the leading contribution to baryon mass does, in fact, scale as N_c^2.
hep-ph/0007140
Fredrick Olness
S. Kuhlmann, J. Huston, J. Morfin, F. Olness, J. Pumplin, J.F. Owens, W.K. Tung, J.J. Whitmore
Large-x Parton Distributions
LaTeX, 9 pages, 7 figures. Invited talk presented at the ``Workshop on Nucleon Structure in the High x-Bjorken Region (HiX2000),'' Temple University, Philadelphia, Pennsylvania, March 30-April 1, 2000
null
null
SMU-HEP/00-10
hep-ph
null
Reliable knowledge of parton distributions at large x is crucial for many searches for new physics signals in the next generation of collider experiments. Although these are generally well determined in the small and medium x range, it has been shown that their uncertainty grows rapidly for x>0.1. We examine the status of the gluon and quark distributions in light of new questions that have been raised in the past two years about "large-x" parton distributions, as well as recent measurements which have improved the parton uncertainties. Finally, we provide a status report of the data used in the global analysis, and note some of the open issues where future experiments, including those planned for Jefferson Labs, might contribute.
[ { "created": "Thu, 13 Jul 2000 16:37:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kuhlmann", "S.", "" ], [ "Huston", "J.", "" ], [ "Morfin", "J.", "" ], [ "Olness", "F.", "" ], [ "Pumplin", "J.", "" ], [ "Owens", "J. F.", "" ], [ "Tung", "W. K.", "" ], [ "Whitmore", "J. J.", "" ] ]
Reliable knowledge of parton distributions at large x is crucial for many searches for new physics signals in the next generation of collider experiments. Although these are generally well determined in the small and medium x range, it has been shown that their uncertainty grows rapidly for x>0.1. We examine the status of the gluon and quark distributions in light of new questions that have been raised in the past two years about "large-x" parton distributions, as well as recent measurements which have improved the parton uncertainties. Finally, we provide a status report of the data used in the global analysis, and note some of the open issues where future experiments, including those planned for Jefferson Labs, might contribute.
hep-ph/9301234
K. Kang
Kyungsik Kang and Alan R. White
Color--Sextet Quark Condensation in QCD
5 pages
null
null
BROWN-HET-886, ANL-HEP-CP-92-118
hep-ph
null
We suggest that the sextet color condensation model is not only the simplest and most attractive scheme to modify the standard model but also may already have some ``experimental" support. The crucial test may be to observe a short-- lived axion--like $\eta_6$ of mass around 60 GeV/$c^2$ that can produce high energy photon pairs diffractively at hadron colliders and also radiatively from $Z^0$ at high energy $e^+ e^-$ colliders. Here we show how high--energy forward scattering can be affected by diffractive production of the $\eta_6$. Presented to the DPF-92 meeting.
[ { "created": "Tue, 12 Jan 1993 21:32:56 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kang", "Kyungsik", "" ], [ "White", "Alan R.", "" ] ]
We suggest that the sextet color condensation model is not only the simplest and most attractive scheme to modify the standard model but also may already have some ``experimental" support. The crucial test may be to observe a short-- lived axion--like $\eta_6$ of mass around 60 GeV/$c^2$ that can produce high energy photon pairs diffractively at hadron colliders and also radiatively from $Z^0$ at high energy $e^+ e^-$ colliders. Here we show how high--energy forward scattering can be affected by diffractive production of the $\eta_6$. Presented to the DPF-92 meeting.
1509.06199
Glenn D. Starkman
Bryan W. Lynn and Glenn D. Starkman
Global $SU(3)_C\times SU(2)_L\times U(1)_Y$ linear sigma model: axial-vector Ward Takahashi identities, and decoupling of certain heavy BSM particles due to the Goldstone theorem
Focus on technical results -- existence of a new symmetry represented by two towers of Ward-Takahashi Identities
Phys. Rev. D 96, 065006 (2017)
10.1103/PhysRevD.96.065006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dedicated to the memory of Raymond Stora (1930-2015). In the $SU(2)_L\times SU(2)_R$ Linear Sigma Model with PCAC, towers of Ward-Takahashi Identities (WTI) have long been known to give relations among 1-Scalar-Particle-Irreducible Green's functions, and among I- Scalar-Particle-Reducible T-Matrix elements, for external scalars (i.e. the Brout-Englert-Higgs scalar and 3 pseudoscalars). We extend these WTI and the resulting relations to the $SU(3)_C\times SU(2)_L\times U(1)_Y$ Linear Sigma Model including the heaviest generation of Standard Model (SM) fermions supplemented with the minimum necessary neutrino content -- right-handed neutrinos and Yukawa-coupling-induced Dirac neutrino mass. We extract powerful constraints on the effective Lagrangian: e.g. showing that they make separate tadpole renormalization unnecessary, and guarantee infra-red finiteness. Crucially, ultra-violet quadratic divergences (UVQD) and all other relevant operators contribute only to $m_\pi^2$, a Nambu-Goldstone boson (NGB) mass-squared. A WTI between T-Matrix elements (i.e. the Goldstone Theorem) then enforces $ m_\pi^2=0$ for the true NGB in the spontaneous symmetry breaking mode of the theory. All relevant operator contributions originating to all-loop-orders from virtual scalars, quarks and leptons, vanish identically! Our regularization-scheme-independent results are unchanged by the addition of certain heavy CP-conserving matter, such as originate in certain Beyond the SM models. We demonstrate this with two examples: a heavy singlet real scalar field with $Z_2$ symmetry and no VEV; and a heavy singlet right-handed Type I See-saw Majorana neutrino. Specifically, we prove that these heavy degrees of freedom decouple completely from the low-energy effective Lagrangian, contributing only irrelevant operators after quartic-coupling renormalization.
[ { "created": "Mon, 21 Sep 2015 12:06:13 GMT", "version": "v1" }, { "created": "Sun, 14 Aug 2016 18:11:20 GMT", "version": "v2" }, { "created": "Thu, 6 Jul 2017 17:49:39 GMT", "version": "v3" }, { "created": "Sat, 15 Jul 2017 04:42:32 GMT", "version": "v4" } ]
2017-09-20
[ [ "Lynn", "Bryan W.", "" ], [ "Starkman", "Glenn D.", "" ] ]
Dedicated to the memory of Raymond Stora (1930-2015). In the $SU(2)_L\times SU(2)_R$ Linear Sigma Model with PCAC, towers of Ward-Takahashi Identities (WTI) have long been known to give relations among 1-Scalar-Particle-Irreducible Green's functions, and among I- Scalar-Particle-Reducible T-Matrix elements, for external scalars (i.e. the Brout-Englert-Higgs scalar and 3 pseudoscalars). We extend these WTI and the resulting relations to the $SU(3)_C\times SU(2)_L\times U(1)_Y$ Linear Sigma Model including the heaviest generation of Standard Model (SM) fermions supplemented with the minimum necessary neutrino content -- right-handed neutrinos and Yukawa-coupling-induced Dirac neutrino mass. We extract powerful constraints on the effective Lagrangian: e.g. showing that they make separate tadpole renormalization unnecessary, and guarantee infra-red finiteness. Crucially, ultra-violet quadratic divergences (UVQD) and all other relevant operators contribute only to $m_\pi^2$, a Nambu-Goldstone boson (NGB) mass-squared. A WTI between T-Matrix elements (i.e. the Goldstone Theorem) then enforces $ m_\pi^2=0$ for the true NGB in the spontaneous symmetry breaking mode of the theory. All relevant operator contributions originating to all-loop-orders from virtual scalars, quarks and leptons, vanish identically! Our regularization-scheme-independent results are unchanged by the addition of certain heavy CP-conserving matter, such as originate in certain Beyond the SM models. We demonstrate this with two examples: a heavy singlet real scalar field with $Z_2$ symmetry and no VEV; and a heavy singlet right-handed Type I See-saw Majorana neutrino. Specifically, we prove that these heavy degrees of freedom decouple completely from the low-energy effective Lagrangian, contributing only irrelevant operators after quartic-coupling renormalization.
1605.01629
Qin Chang
Qin Chang, Xiaohui Hu, Junfeng Sun, Xiaolin Wang and Yueling Yang
Study of nonleptonic $B_{q}^{\ast}$ ${\to}$ $D_{q}V$ and $P_{q} D^*$ weak decays
15 pages, 3 tables; the version published in Adv. High Energy Phys
Adv.High Energy Phys. 2015 (2015) 767523
10.1155/2015/767523
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the powerful capability of measurement for the $b$-flavored hadron rare decays at LHC and SuperKEKB/Belle-II, the nonleptonic $\bar{B}^{\ast}$ ${\to}$ $D\bar{D}^{\ast}$, $D{\rho^-}$, $DK^{\ast-}$, ${\pi}D^{\ast}$ and $KD^{\ast}$ weak decays are studied in detail. With the amplitudes calculated with factorization approach and the form factors of $B^{\ast}$ transition into pseudoscalar meson evaluated with the BSW model, branching fractions and polarization fractions are firstly presented. Numerically, the CKM-favored $\bar{B}_{q}^{\ast}$ ${\to}$ $D_{q}D_{s}^{{\ast}-}$ and $D_{q}{\rho}^{-}$ decays have large branching fractions, $\sim$ $10^{-8}$, which should be sought for with priority and firstly observed by LHC and Belle-II experiments. The $\bar{B}^{\ast}_q$ ${\to}$ $D_qK^{\ast}$ and $D_q{\rho}$ decays are dominated by the longitudinal polarization states. While, the parallel polarization fractions of $\bar{B}^{\ast}_q$ ${\to}$ $D_q\bar{D}^{\ast}$ decays are comparable with the longitudinal ones, numerically, $f_{\parallel}$ $+$ $f_{L}$ ${\simeq}$ 95\% and $f_{L}:f_{\parallel}$ $\simeq$ $5:4$. Some comparisons between $\bar{B}^{*0}_q$ $\to$ $D_q V$ and their corresponding $\bar{B}^{0}_q$ $\to$ $D^*_q V$ decays are performed, and the relation $ f_{L,\parallel}(\bar{B}^{\ast 0}\to D V)\simeq f_{L,\parallel}(\bar{B}^0\to D^{\ast +} V^-) $ is presented. Besides, with the implication of $SU(3)$ flavor symmetry, some useful ratios $ R_{\rm du}$ and $ R_{\rm ds}$ are discussed in detail, and suggested to be verified experimentally.
[ { "created": "Thu, 5 May 2016 15:48:59 GMT", "version": "v1" } ]
2016-05-06
[ [ "Chang", "Qin", "" ], [ "Hu", "Xiaohui", "" ], [ "Sun", "Junfeng", "" ], [ "Wang", "Xiaolin", "" ], [ "Yang", "Yueling", "" ] ]
Motivated by the powerful capability of measurement for the $b$-flavored hadron rare decays at LHC and SuperKEKB/Belle-II, the nonleptonic $\bar{B}^{\ast}$ ${\to}$ $D\bar{D}^{\ast}$, $D{\rho^-}$, $DK^{\ast-}$, ${\pi}D^{\ast}$ and $KD^{\ast}$ weak decays are studied in detail. With the amplitudes calculated with factorization approach and the form factors of $B^{\ast}$ transition into pseudoscalar meson evaluated with the BSW model, branching fractions and polarization fractions are firstly presented. Numerically, the CKM-favored $\bar{B}_{q}^{\ast}$ ${\to}$ $D_{q}D_{s}^{{\ast}-}$ and $D_{q}{\rho}^{-}$ decays have large branching fractions, $\sim$ $10^{-8}$, which should be sought for with priority and firstly observed by LHC and Belle-II experiments. The $\bar{B}^{\ast}_q$ ${\to}$ $D_qK^{\ast}$ and $D_q{\rho}$ decays are dominated by the longitudinal polarization states. While, the parallel polarization fractions of $\bar{B}^{\ast}_q$ ${\to}$ $D_q\bar{D}^{\ast}$ decays are comparable with the longitudinal ones, numerically, $f_{\parallel}$ $+$ $f_{L}$ ${\simeq}$ 95\% and $f_{L}:f_{\parallel}$ $\simeq$ $5:4$. Some comparisons between $\bar{B}^{*0}_q$ $\to$ $D_q V$ and their corresponding $\bar{B}^{0}_q$ $\to$ $D^*_q V$ decays are performed, and the relation $ f_{L,\parallel}(\bar{B}^{\ast 0}\to D V)\simeq f_{L,\parallel}(\bar{B}^0\to D^{\ast +} V^-) $ is presented. Besides, with the implication of $SU(3)$ flavor symmetry, some useful ratios $ R_{\rm du}$ and $ R_{\rm ds}$ are discussed in detail, and suggested to be verified experimentally.
hep-ph/0406226
M. Benjamin Portheault
Benjamin Portheault
Strange sea asymmetry from global QCD fits
Presentation at the DIS 2003 conference
International Workshop On Deep Inelastic Scattering, Russie (2003)
null
null
hep-ph
null
We present a preliminary account of a new global QCD analysis of DIS data, including recent $\nu, \bar \nu$ DIS measurements. The model-independent cross section reanalysis by CCFR allows a new determination of the strange sea asymmetry, whose first moment is found to be small. The impact on the NuTeV measurement of $\sin^2 \theta_W$ is discussed.
[ { "created": "Mon, 21 Jun 2004 14:21:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Portheault", "Benjamin", "" ] ]
We present a preliminary account of a new global QCD analysis of DIS data, including recent $\nu, \bar \nu$ DIS measurements. The model-independent cross section reanalysis by CCFR allows a new determination of the strange sea asymmetry, whose first moment is found to be small. The impact on the NuTeV measurement of $\sin^2 \theta_W$ is discussed.
2005.02009
Michel Planat Dr
Michel Planat, Raymond Aschheim, Marcelo M. Amaral and Klee Irwin
Informationally complete characters for quark and lepton mixings
14 pages, 1 figure, 8 tables
MDPI Symmetry 12 (6), 1000 (2020)
10.3390/sym12061000
null
hep-ph math.GR math.RT quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A popular account of the mixing patterns for the three generations of quarks and leptons is through the characters $\kappa$ of a finite group $G$. Here we introduce a $d$-dimensional Hilbert space with $d=cc(G)$, the number of conjugacy classes of $G$. Groups under consideration should follow two rules, (a) the character table contains both two- and three-dimensional representations with at least one of them faithful and (b) there are minimal informationally complete measurements under the action of a $d$-dimensional Pauli group over the characters of these representations. Groups with small $d$ that satisfy these rules coincide in a large part with viable ones derived so far for reproducing simultaneously the CKM (quark) and PNMS (lepton) mixing matrices. Groups leading to physical $CP$ violation are singled out.
[ { "created": "Tue, 5 May 2020 08:48:52 GMT", "version": "v1" } ]
2020-06-19
[ [ "Planat", "Michel", "" ], [ "Aschheim", "Raymond", "" ], [ "Amaral", "Marcelo M.", "" ], [ "Irwin", "Klee", "" ] ]
A popular account of the mixing patterns for the three generations of quarks and leptons is through the characters $\kappa$ of a finite group $G$. Here we introduce a $d$-dimensional Hilbert space with $d=cc(G)$, the number of conjugacy classes of $G$. Groups under consideration should follow two rules, (a) the character table contains both two- and three-dimensional representations with at least one of them faithful and (b) there are minimal informationally complete measurements under the action of a $d$-dimensional Pauli group over the characters of these representations. Groups with small $d$ that satisfy these rules coincide in a large part with viable ones derived so far for reproducing simultaneously the CKM (quark) and PNMS (lepton) mixing matrices. Groups leading to physical $CP$ violation are singled out.
hep-ph/9612482
Tomohiro Matsuda
Tomohiro Matsuda
Large N expansion in global and local supersymmetric theories
64 pages, Latex
null
null
UT-765
hep-ph hep-th
null
A systematic study of large N expansion in supersymmetric theories are given. Supersymmetric O(N) non-linear sigma model in two and three dimensions, massless and massive supersymmetric QCD with $N_{f}<N_{c}-1$ and supergravity models are analyzed in detail. Our main motivation is to discuss how the previously studied mechanism for dynamical generation of gaugino condensation and superpotential is realized in the framework of large N expansion.
[ { "created": "Sun, 29 Dec 1996 05:44:12 GMT", "version": "v1" }, { "created": "Tue, 1 Jul 1997 04:32:38 GMT", "version": "v2" } ]
2008-02-03
[ [ "Matsuda", "Tomohiro", "" ] ]
A systematic study of large N expansion in supersymmetric theories are given. Supersymmetric O(N) non-linear sigma model in two and three dimensions, massless and massive supersymmetric QCD with $N_{f}<N_{c}-1$ and supergravity models are analyzed in detail. Our main motivation is to discuss how the previously studied mechanism for dynamical generation of gaugino condensation and superpotential is realized in the framework of large N expansion.
hep-ph/9211257
null
L. Nellen, K. Mannheim, P.L. Biermann
Neutrino production through hadronic cascades in AGN accretion disks
12 Pages, LaTeX, TK 92 08
Phys.Rev.D47:5270-5274,1993
10.1103/PhysRevD.47.5270
null
hep-ph astro-ph
null
We consider the production of neutrinos in active galactic nuclei (AGN) through hadronic cascades. The initial, high energy nucleons are accelerated in a source above the accretion disk around the central black hole. From the source, the particles diffuse back to the disk and initiate hadronic cascades. The observable output from the cascade are electromagnetic radiation and neutrinos. We use the observed diffuse background X-ray luminosity, which presumably results {}from this process, to predict the diffuse neutrino flux close to existing limits from the Frejus experiment. The resulting neutrino spectrum is $E^{-2}$ down to the $\GeV$ region. We discuss modifications of this scenario which reduce the predicted neutrino flux.
[ { "created": "Tue, 17 Nov 1992 11:09:31 GMT", "version": "v1" } ]
2009-02-18
[ [ "Nellen", "L.", "" ], [ "Mannheim", "K.", "" ], [ "Biermann", "P. L.", "" ] ]
We consider the production of neutrinos in active galactic nuclei (AGN) through hadronic cascades. The initial, high energy nucleons are accelerated in a source above the accretion disk around the central black hole. From the source, the particles diffuse back to the disk and initiate hadronic cascades. The observable output from the cascade are electromagnetic radiation and neutrinos. We use the observed diffuse background X-ray luminosity, which presumably results {}from this process, to predict the diffuse neutrino flux close to existing limits from the Frejus experiment. The resulting neutrino spectrum is $E^{-2}$ down to the $\GeV$ region. We discuss modifications of this scenario which reduce the predicted neutrino flux.
hep-ph/9906377
Dario Sassi Thober
Dario Sassi Thober
The monopoles in the structure of the electron
8 pages
null
null
CPTUS-05/1999
hep-ph
null
The classical electron is presented as made up of an electric charge and two Dirac monopoles of opposite charge performing a magnetic dipole. It is discussed that a valid variational principle for this system can be defined. The Dirac quantization condition for charges can be derived in Quantum Electrodynamics as monopoles are properly defined in the structure. Further comments on the subject are addressed since the proper care of Dirac strings is still an open issue.
[ { "created": "Tue, 15 Jun 1999 20:04:41 GMT", "version": "v1" } ]
2007-05-23
[ [ "Thober", "Dario Sassi", "" ] ]
The classical electron is presented as made up of an electric charge and two Dirac monopoles of opposite charge performing a magnetic dipole. It is discussed that a valid variational principle for this system can be defined. The Dirac quantization condition for charges can be derived in Quantum Electrodynamics as monopoles are properly defined in the structure. Further comments on the subject are addressed since the proper care of Dirac strings is still an open issue.
0812.4910
Ramon Herrera
Sergio del Campo and Ramon Herrera
Intermediate inflation on the brane
12 pages and 2 figures
Phys.Lett.B670:266-270,2009
10.1016/j.physletb.2008.11.014
null
hep-ph astro-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Brane inflationary universe model in the context of intermediate inflation is studied. General conditions for this model to be realizable are discussed. In the high-energy limit we describe in great details the characteristic of this model.
[ { "created": "Mon, 29 Dec 2008 14:10:20 GMT", "version": "v1" } ]
2009-02-26
[ [ "del Campo", "Sergio", "" ], [ "Herrera", "Ramon", "" ] ]
Brane inflationary universe model in the context of intermediate inflation is studied. General conditions for this model to be realizable are discussed. In the high-energy limit we describe in great details the characteristic of this model.
hep-ph/0206065
Giuseppe Nardulli
G. Nardulli (Dipartimento di Fisica Universita' di Bari and I.N.F.N. Sezione di Bari, Italy)
Effective Fields in Dense Quantum Chromodynamics
17 pages, Invited review talk at Workshop on Quark Gluon Plasma and Relativistic Heavy Ions, Frascati, Italy, 14-18 Jan 2002
null
10.1142/9789812776532_0020
BARI-TH 441/02
hep-ph
null
In the high density, low temperature limit, Quantum Chromodynamics exhibits a transition to phases characterized by color superconductivity and energy gaps in the fermion spectra. We review some fundamental results obtained in this area and in particular we describe the low energy effective lagrangian describing the motion of the quasi-particles in the high density medium (High Density Effective Theory).
[ { "created": "Thu, 6 Jun 2002 08:05:55 GMT", "version": "v1" } ]
2017-08-23
[ [ "Nardulli", "G.", "", "Dipartimento di Fisica Universita' di Bari and I.N.F.N.\n Sezione di Bari, Italy" ] ]
In the high density, low temperature limit, Quantum Chromodynamics exhibits a transition to phases characterized by color superconductivity and energy gaps in the fermion spectra. We review some fundamental results obtained in this area and in particular we describe the low energy effective lagrangian describing the motion of the quasi-particles in the high density medium (High Density Effective Theory).
hep-ph/0502001
Keith Olive
John Ellis, Keith A. Olive, Yudi Santoso, and Vassilis C. Spanos
Update on the Direct Detection of Supersymmetric Dark Matter
25 pages, 28 eps figures
Phys.Rev.D71:095007,2005
10.1103/PhysRevD.71.095007
CERN-PH-TH/2005-002, UMN-TH-2342/05, FTPI-MINN-05/01
hep-ph astro-ph
null
We compare updated predictions for the elastic scattering of supersymmetric neutralino dark matter with the improved experimental upper limit recently published by CDMS II. We take into account the possibility that the \pi-nucleon \Sigma term may be somewhat larger than was previously considered plausible, as may be supported by the masses of exotic baryons reported recently. We also incorporate the new central value of m_t, which affects indirectly constraints on the supersymmetric parameter space, for example via calculations of the relic density. Even if a large value of \Sigma is assumed, the CDMS II data currently exclude only small parts of the parameter space in the constrained MSSM (CMSSM) with universal soft supersymmetry-breaking Higgs, squark and slepton masses. None of the previously-proposed CMSSM benchmark scenarios is excluded for any value of \Sigma, and the CDMS II data do not impinge on the domains of the CMSSM parameter space favoured at the 90 % confidence level in a recent likelihood analysis. However, some models with non-universal Higgs, squark and slepton masses and neutralino masses \lappeq 700 GeV are excluded by the CDMS II data.
[ { "created": "Mon, 31 Jan 2005 21:00:28 GMT", "version": "v1" } ]
2010-04-06
[ [ "Ellis", "John", "" ], [ "Olive", "Keith A.", "" ], [ "Santoso", "Yudi", "" ], [ "Spanos", "Vassilis C.", "" ] ]
We compare updated predictions for the elastic scattering of supersymmetric neutralino dark matter with the improved experimental upper limit recently published by CDMS II. We take into account the possibility that the \pi-nucleon \Sigma term may be somewhat larger than was previously considered plausible, as may be supported by the masses of exotic baryons reported recently. We also incorporate the new central value of m_t, which affects indirectly constraints on the supersymmetric parameter space, for example via calculations of the relic density. Even if a large value of \Sigma is assumed, the CDMS II data currently exclude only small parts of the parameter space in the constrained MSSM (CMSSM) with universal soft supersymmetry-breaking Higgs, squark and slepton masses. None of the previously-proposed CMSSM benchmark scenarios is excluded for any value of \Sigma, and the CDMS II data do not impinge on the domains of the CMSSM parameter space favoured at the 90 % confidence level in a recent likelihood analysis. However, some models with non-universal Higgs, squark and slepton masses and neutralino masses \lappeq 700 GeV are excluded by the CDMS II data.
2103.06773
Johannes Braathen
Johannes Braathen, Mark D. Goodsell, Sebastian Pa{\ss}ehr, Emanuelle Pinsard
Expectation management
25 pages, 13 figures; v2: added explanations, matches version published in EPJC
null
10.1140/epjc/s10052-021-09285-4
DESY 21-030, TTK-21-07
hep-ph
http://creativecommons.org/licenses/by/4.0/
We consider the application of a Fleischer$-$Jegerlehner-like treatment of tadpoles to the calculation of neutral scalar masses (including the Higgs) in general theories beyond the Standard Model. This is especially useful when the theory contains new scalars associated with a small expectation value, but comes with its own disadvantages. We show that these can be overcome by combining with effective field theory matching. We provide the formalism in this modified approach for matching the quartic coupling of the Higgs via pole masses at one loop, and apply it to both a toy model and to the $\mu$NMSSM as prototypes where the standard treatment can break down.
[ { "created": "Thu, 11 Mar 2021 16:33:50 GMT", "version": "v1" }, { "created": "Thu, 5 Aug 2021 17:28:08 GMT", "version": "v2" } ]
2021-08-06
[ [ "Braathen", "Johannes", "" ], [ "Goodsell", "Mark D.", "" ], [ "Paßehr", "Sebastian", "" ], [ "Pinsard", "Emanuelle", "" ] ]
We consider the application of a Fleischer$-$Jegerlehner-like treatment of tadpoles to the calculation of neutral scalar masses (including the Higgs) in general theories beyond the Standard Model. This is especially useful when the theory contains new scalars associated with a small expectation value, but comes with its own disadvantages. We show that these can be overcome by combining with effective field theory matching. We provide the formalism in this modified approach for matching the quartic coupling of the Higgs via pole masses at one loop, and apply it to both a toy model and to the $\mu$NMSSM as prototypes where the standard treatment can break down.
2204.05510
Yan Li
Yan Li and Jia-Jun Wu
Inverse scattering problem with a bare state
28 pages 2 figures
Phys. Rev. D 105, 116024 (2022)
10.1103/PhysRevD.105.116024
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In hadron physics, molecular-like multihadron states can interact with compact multiquark states. The latter are modeled as bare states in the Hilbert space of a potential model. In this work, we study several potential models relevant to the bare state, and solve their inverse scattering problems. The first model, called "cc", is a separable potential model. We show that it can approximate (single-channel short-range) $S$-wave near-threshold physics with an error of $\mathcal{O}(\beta^3/M_V^3)$, where $\beta$ sets the maximum momentum of the near-threshold region and $M_V$ is the typical scale of the potential. The second model, called "bc", serves as the bare-state-dominance approximation, where interaction between continuum states is ignored. Under this model, even though the bare state is always crucial for a bound state's generation, a shallow bound state naturally tends to have a small bare-state proportion. Therefore, we need other quantities to quantify the importance of the bare state. The last model, called "bcc", is a combination of the first two models. This model not only serves as a correction to the bare-state-dominance approximation, but can also be used to understand the interplay between quark and hadron degrees of freedom. This model naturally leads to the presence of a Castillejo-Dalitz-Dyson (CDD) zero. We consider the energy decomposition of a bound state. The potential ratio of the bare-continuum interaction to the continuum self-interaction is proposed to understand how the bound state is generated. Model independently, an inequality for the potential ratio is derived. Based on the model "bcc", the CDD zero can be used to estimate the potential ratio. Finally, we apply these studies to the deuteron, $\rho$ meson, and $D_{s0}^*(2317)$, and analyze their properties.
[ { "created": "Tue, 12 Apr 2022 03:47:10 GMT", "version": "v1" }, { "created": "Sun, 3 Jul 2022 00:16:05 GMT", "version": "v2" } ]
2022-07-05
[ [ "Li", "Yan", "" ], [ "Wu", "Jia-Jun", "" ] ]
In hadron physics, molecular-like multihadron states can interact with compact multiquark states. The latter are modeled as bare states in the Hilbert space of a potential model. In this work, we study several potential models relevant to the bare state, and solve their inverse scattering problems. The first model, called "cc", is a separable potential model. We show that it can approximate (single-channel short-range) $S$-wave near-threshold physics with an error of $\mathcal{O}(\beta^3/M_V^3)$, where $\beta$ sets the maximum momentum of the near-threshold region and $M_V$ is the typical scale of the potential. The second model, called "bc", serves as the bare-state-dominance approximation, where interaction between continuum states is ignored. Under this model, even though the bare state is always crucial for a bound state's generation, a shallow bound state naturally tends to have a small bare-state proportion. Therefore, we need other quantities to quantify the importance of the bare state. The last model, called "bcc", is a combination of the first two models. This model not only serves as a correction to the bare-state-dominance approximation, but can also be used to understand the interplay between quark and hadron degrees of freedom. This model naturally leads to the presence of a Castillejo-Dalitz-Dyson (CDD) zero. We consider the energy decomposition of a bound state. The potential ratio of the bare-continuum interaction to the continuum self-interaction is proposed to understand how the bound state is generated. Model independently, an inequality for the potential ratio is derived. Based on the model "bcc", the CDD zero can be used to estimate the potential ratio. Finally, we apply these studies to the deuteron, $\rho$ meson, and $D_{s0}^*(2317)$, and analyze their properties.
2312.08796
Xu-Chang Zheng
Guang-Yu Wang, Xu-Chang Zheng, Xing-Gang Wu, Guang-Zhi Xu
$Z$-boson decays into $S$-wave quarkonium plus a photon up to ${\cal O}(\alpha_{s} v^2)$ corrections
8 pages, 2 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this paper, we calculate the decay widths and branching fractions for the decays $Z \to H+ \gamma$ up to ${\cal O}(\alpha_{s} v^2)$ accuracy within the framework of nonrelativistic QCD, where $H$ stands for the $S$-wave quarkonium $\eta_c$, $J/\psi$, $\eta_b$ or $\Upsilon$, respectively. To compare with the leading-order terms, those corrections show good perturbative behavior as expected. It is found that contributions from the next-to-leading order QCD correction ${\cal O}(\alpha_{s}v^0)$, the relativistic correction ${\cal O}(\alpha^{0}_{s}v^2)$ and their joint correction ${\cal O}(\alpha_{s} v^2)$ are sizable and comparable to each other, especially for the charmonium case. Thus we need to take all of them into consideration for a sound estimation. For a high luminosity electron-positron collider running around the $Z$-pole, due to $Z$-boson resonance effect, sizable events could be produced from those rare decay channels.
[ { "created": "Thu, 14 Dec 2023 10:30:32 GMT", "version": "v1" } ]
2023-12-15
[ [ "Wang", "Guang-Yu", "" ], [ "Zheng", "Xu-Chang", "" ], [ "Wu", "Xing-Gang", "" ], [ "Xu", "Guang-Zhi", "" ] ]
In this paper, we calculate the decay widths and branching fractions for the decays $Z \to H+ \gamma$ up to ${\cal O}(\alpha_{s} v^2)$ accuracy within the framework of nonrelativistic QCD, where $H$ stands for the $S$-wave quarkonium $\eta_c$, $J/\psi$, $\eta_b$ or $\Upsilon$, respectively. To compare with the leading-order terms, those corrections show good perturbative behavior as expected. It is found that contributions from the next-to-leading order QCD correction ${\cal O}(\alpha_{s}v^0)$, the relativistic correction ${\cal O}(\alpha^{0}_{s}v^2)$ and their joint correction ${\cal O}(\alpha_{s} v^2)$ are sizable and comparable to each other, especially for the charmonium case. Thus we need to take all of them into consideration for a sound estimation. For a high luminosity electron-positron collider running around the $Z$-pole, due to $Z$-boson resonance effect, sizable events could be produced from those rare decay channels.
hep-ph/0512275
Takuya Mizoguchi
Minoru Biyajima, Takuya Mizoguchi and Naomichi Suzuki
Third order Bose-Einstein correlations by means of Coulomb wave function revisited
9 pages, 5 figures
Phys.Lett. B637 (2006) 64-68
10.1016/j.physletb.2006.03.067
null
hep-ph
null
In previous works, in order to include correction by the Coulomb wave function in Bose-Einstein correlations (BEC), the two-body Coulomb scattering wave functions have been utilized in the formulation of three-body BEC. However, the three-body Coulomb scattering wave function, which satisfies approximately the three-body Coulomb scattering Schrodinger equation, cannot be written by the product of the two-body scattering wave functions. Therefore, we reformulate the three-body BEC, and reanalyze the data. A set of reasonable parameters is obtained.
[ { "created": "Wed, 21 Dec 2005 18:23:56 GMT", "version": "v1" }, { "created": "Wed, 22 Mar 2006 18:19:41 GMT", "version": "v2" } ]
2009-11-11
[ [ "Biyajima", "Minoru", "" ], [ "Mizoguchi", "Takuya", "" ], [ "Suzuki", "Naomichi", "" ] ]
In previous works, in order to include correction by the Coulomb wave function in Bose-Einstein correlations (BEC), the two-body Coulomb scattering wave functions have been utilized in the formulation of three-body BEC. However, the three-body Coulomb scattering wave function, which satisfies approximately the three-body Coulomb scattering Schrodinger equation, cannot be written by the product of the two-body scattering wave functions. Therefore, we reformulate the three-body BEC, and reanalyze the data. A set of reasonable parameters is obtained.
1212.2886
John Ellis
M. Citron, J. Ellis, F. Luo, J. Marrouche, K. A. Olive and K. J. de Vries
The End of the CMSSM Coannihilation Strip is Nigh
33 pages, 19 pdf figures
null
10.1103/PhysRevD.87.036012
KCL-PH-TH/2012-46; LCTS/2012-32; CERN-PH-TH/2012-331; UMN--TH--3127/12; FTPI--MINN--12/38
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A recent global fit to the CMSSM incorporating current constraints on supersymmetry, including missing transverse energy searches at the LHC, BR(B_s to mu+ mu-) and the direct XENON100 search for dark matter, favours points towards the end of the stau-neutralino (stau_1- chi) coannihilation strip with relatively large m_1/2 and 10 < tan beta < 40 and points in the H/A rapid-annihilation funnel with tan beta ~ 50. The coannihilation points typically have m_stau_1-m_chi < 5 GeV, and a significant fraction, including the most-favoured point, has m_stau_1-m_chi < m_tau. In such a case, the stau_1 lifetime would be so long that the stau_1 would be detectable as a long-lived massive charged particle that may decay inside or outside the apparatus. We show that CMSSM scenarios close to the tip of the coannihilation strip for tan beta < 40 are already excluded by LHC searches for massive charged particles, and discuss the prospects for their detection in the CMS and ATLAS detectors via time-of-flight measurements, anomalous heavy ionization or decays into one or more soft charged particles.
[ { "created": "Wed, 12 Dec 2012 17:04:47 GMT", "version": "v1" } ]
2013-03-14
[ [ "Citron", "M.", "" ], [ "Ellis", "J.", "" ], [ "Luo", "F.", "" ], [ "Marrouche", "J.", "" ], [ "Olive", "K. A.", "" ], [ "de Vries", "K. J.", "" ] ]
A recent global fit to the CMSSM incorporating current constraints on supersymmetry, including missing transverse energy searches at the LHC, BR(B_s to mu+ mu-) and the direct XENON100 search for dark matter, favours points towards the end of the stau-neutralino (stau_1- chi) coannihilation strip with relatively large m_1/2 and 10 < tan beta < 40 and points in the H/A rapid-annihilation funnel with tan beta ~ 50. The coannihilation points typically have m_stau_1-m_chi < 5 GeV, and a significant fraction, including the most-favoured point, has m_stau_1-m_chi < m_tau. In such a case, the stau_1 lifetime would be so long that the stau_1 would be detectable as a long-lived massive charged particle that may decay inside or outside the apparatus. We show that CMSSM scenarios close to the tip of the coannihilation strip for tan beta < 40 are already excluded by LHC searches for massive charged particles, and discuss the prospects for their detection in the CMS and ATLAS detectors via time-of-flight measurements, anomalous heavy ionization or decays into one or more soft charged particles.
1101.4611
Chong Sheng Li
Jun Gao, Chong Sheng Li, Jian Wang, Hua Xing Zhu, and C.-P. Yuan
Next-to-leading QCD effect to the quark compositeness search at the LHC
Published version in Phys.Rev.Lett
Phys.Rev.Lett.106:142001,2011
10.1103/PhysRevLett.106.142001
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, the CMS and ATLAS Collaborations at the CERN Large Hadron Collider (LHC) have set exclusion limits on the quark compositeness scale by comparing their data to the leading order and the scaled next-to-leading order (NLO) QCD calculations, respectively. In this Letter, we present the exact NLO QCD corrections to the dijet production induced by the quark contact interactions. We show that as compared to the exact calculation, the scaled NLO QCD prediction adopted by the ATLAS Collaboration has overestimated the new physics effect on some direct observables by more than 30% and renders a higher limit on the quark compositeness scale. The destructive contribution from the exact NLO correction will also lower the compositeness scale limit set by the CMS Collaboration.
[ { "created": "Mon, 24 Jan 2011 18:15:12 GMT", "version": "v1" }, { "created": "Wed, 6 Apr 2011 13:37:17 GMT", "version": "v2" } ]
2011-04-20
[ [ "Gao", "Jun", "" ], [ "Li", "Chong Sheng", "" ], [ "Wang", "Jian", "" ], [ "Zhu", "Hua Xing", "" ], [ "Yuan", "C. -P.", "" ] ]
Recently, the CMS and ATLAS Collaborations at the CERN Large Hadron Collider (LHC) have set exclusion limits on the quark compositeness scale by comparing their data to the leading order and the scaled next-to-leading order (NLO) QCD calculations, respectively. In this Letter, we present the exact NLO QCD corrections to the dijet production induced by the quark contact interactions. We show that as compared to the exact calculation, the scaled NLO QCD prediction adopted by the ATLAS Collaboration has overestimated the new physics effect on some direct observables by more than 30% and renders a higher limit on the quark compositeness scale. The destructive contribution from the exact NLO correction will also lower the compositeness scale limit set by the CMS Collaboration.
2006.07174
Giorgio Arcadi
Tommi Alanne, Giorgio Arcadi, Florian Goertz, Valentin Tenorth, Stefan Vogl
Model-independent constraints with extended dark matter EFT
42 pages, 16 figures
null
10.1007/JHEP10(2020)172
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We systematically explore the phenomenology of the recently proposed extended dark matter effective field theory (\eDMEFT), which allows for a consistent effective description of DM scenarios across different energy scales. The framework remains applicable at collider energies and is capable of reproducing the correct relic abundance by including a dynamical mediator particle to the dark sector, while maintaining correlations dictated by gauge invariance in a `model-independent' way. Taking into account present and future constraints from direct- and indirect-detection experiments, from collider searches for missing energy and for scalar resonances in vector-boson, di-jet, and Higgs-pair final states, as well as from the relic abundance as measured by Planck, we determine viable regions in the parameter space, both for scalar and pseudoscalar mediator. In particular, we point out regions where cancellations in the direct-detection cross section appear leading to allowed islands for scalar mediators that could be missed in a naive simplified-model approach, but are present in the full $D=5$ effective theory, as well as a general opening of the parameter space due to consistently considering all operators at a given mass dimension. Thus, canonical WIMP-like scenarios can survive even the next generation of direct-detection experiments in different mass regimes, while potentially becoming testable at the high-luminosity LHC.
[ { "created": "Fri, 12 Jun 2020 13:32:22 GMT", "version": "v1" } ]
2020-12-02
[ [ "Alanne", "Tommi", "" ], [ "Arcadi", "Giorgio", "" ], [ "Goertz", "Florian", "" ], [ "Tenorth", "Valentin", "" ], [ "Vogl", "Stefan", "" ] ]
We systematically explore the phenomenology of the recently proposed extended dark matter effective field theory (\eDMEFT), which allows for a consistent effective description of DM scenarios across different energy scales. The framework remains applicable at collider energies and is capable of reproducing the correct relic abundance by including a dynamical mediator particle to the dark sector, while maintaining correlations dictated by gauge invariance in a `model-independent' way. Taking into account present and future constraints from direct- and indirect-detection experiments, from collider searches for missing energy and for scalar resonances in vector-boson, di-jet, and Higgs-pair final states, as well as from the relic abundance as measured by Planck, we determine viable regions in the parameter space, both for scalar and pseudoscalar mediator. In particular, we point out regions where cancellations in the direct-detection cross section appear leading to allowed islands for scalar mediators that could be missed in a naive simplified-model approach, but are present in the full $D=5$ effective theory, as well as a general opening of the parameter space due to consistently considering all operators at a given mass dimension. Thus, canonical WIMP-like scenarios can survive even the next generation of direct-detection experiments in different mass regimes, while potentially becoming testable at the high-luminosity LHC.
2406.11312
Laurin Pannullo
Laurin Pannullo, Marc Wagner, Marc Winstel
Regularization effects in the Nambu-Jona-Lasinio model: Strong scheme dependence of inhomogeneous phases and persistence of the moat regime
16 pages, 11 figures, 12 pages appendix & references
null
null
null
hep-ph hep-lat
http://creativecommons.org/licenses/by/4.0/
This work investigates the phase structure of the non-renormalizable (3+1)-dimensional Nambu-Jona-Lasinio (NJL) model with particular focus on inhomogeneous phases (IPs), where the chiral condensate is non-uniform in space, and the closely related moat regimes, where mesonic dispersion relations favor non-vanishing momenta. We use the mean-field approximation and consider five different regularization schemes including three lattice discretizations. The results within the different regularization schemes are systematically analyzed in order to study the dependence of the IP on the choice of regulatization scheme and regulator value. The IP exhibits a drastic dependence on the chosen regularization scheme rendering any physical interpretation of results on inhomogeneous phases in this model doubtful. In contrast, we find only a mild scheme dependence of the moat regime suggesting that its existence is a consequence of the action of the NJL model and its symmetries and, thus, that it might also exist in QCD.
[ { "created": "Mon, 17 Jun 2024 08:19:16 GMT", "version": "v1" } ]
2024-06-18
[ [ "Pannullo", "Laurin", "" ], [ "Wagner", "Marc", "" ], [ "Winstel", "Marc", "" ] ]
This work investigates the phase structure of the non-renormalizable (3+1)-dimensional Nambu-Jona-Lasinio (NJL) model with particular focus on inhomogeneous phases (IPs), where the chiral condensate is non-uniform in space, and the closely related moat regimes, where mesonic dispersion relations favor non-vanishing momenta. We use the mean-field approximation and consider five different regularization schemes including three lattice discretizations. The results within the different regularization schemes are systematically analyzed in order to study the dependence of the IP on the choice of regulatization scheme and regulator value. The IP exhibits a drastic dependence on the chosen regularization scheme rendering any physical interpretation of results on inhomogeneous phases in this model doubtful. In contrast, we find only a mild scheme dependence of the moat regime suggesting that its existence is a consequence of the action of the NJL model and its symmetries and, thus, that it might also exist in QCD.
2102.11303
Jorge C. Romao
S\'ergio Carr\^olo, Jorge C. Rom\~ao, Jo\~ao P. Silva and Francisco Vaz\~ao
Symmetry and decoupling in multi Higgs models
12 pages
Phys. Rev. D 103, 075026 (2021)
10.1103/PhysRevD.103.075026
CFTP/21-004
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study the scalar sector of the most general multi Higgs doublet model satisfying explicitly an exact symmetry. We prove that such a model will exhibit decoupling if and only if the vacuum also satisfies the same symmetry. This general property is also shown independently and explicitly for three Higgs doublet models, by considering in detail all symmetry-constrained models and their possible vacua. We also discuss some specific characteristics of different decoupling patterns.
[ { "created": "Mon, 22 Feb 2021 19:01:03 GMT", "version": "v1" } ]
2021-04-28
[ [ "Carrôlo", "Sérgio", "" ], [ "Romão", "Jorge C.", "" ], [ "Silva", "João P.", "" ], [ "Vazão", "Francisco", "" ] ]
We study the scalar sector of the most general multi Higgs doublet model satisfying explicitly an exact symmetry. We prove that such a model will exhibit decoupling if and only if the vacuum also satisfies the same symmetry. This general property is also shown independently and explicitly for three Higgs doublet models, by considering in detail all symmetry-constrained models and their possible vacua. We also discuss some specific characteristics of different decoupling patterns.
hep-ph/0510247
Dmitry Shirkov V.
D.V.Shirkov
QCD Effective Couplings in Minkowskian and Euclidean Domains
Contribution to proceedings of "QCD@Work2005" meeting (Bari, July 2005), 7 pages, 3 figures; v2: few other applications (with related references)added
null
10.1063/1.2163751
null
hep-ph
null
We argue for essential upgrading of the defining equations (9.5) and (9.6) in Section 9.2 "The QCD coupling ... " of PDG review and their use for data analysis in the light of recent development of the QCD theory. Our claim is twofold. First, instead of universal expression (9.5) for QCD coupling $\bar{\alpha}_s$, one should use various ghost-free couplings $\alpha_E(Q^2), \alpha_M(s)...$ specific for a given physical representation, Euclidean, Mincowskian etc. Second, instead of power expansion (9.6) for observable, we recommend to use nonpower functional ones over particular functional sets ${{\cal A}_k(Q^2)}$, ${{\mathfrak A}_k(s)}...$ related by suitable integral transformations. We remind that use of this modified prescription results in a better correspondence of reanalyzed low energy data with the high energy ones.
[ { "created": "Wed, 19 Oct 2005 09:30:32 GMT", "version": "v1" }, { "created": "Wed, 26 Oct 2005 09:00:49 GMT", "version": "v2" } ]
2009-11-11
[ [ "Shirkov", "D. V.", "" ] ]
We argue for essential upgrading of the defining equations (9.5) and (9.6) in Section 9.2 "The QCD coupling ... " of PDG review and their use for data analysis in the light of recent development of the QCD theory. Our claim is twofold. First, instead of universal expression (9.5) for QCD coupling $\bar{\alpha}_s$, one should use various ghost-free couplings $\alpha_E(Q^2), \alpha_M(s)...$ specific for a given physical representation, Euclidean, Mincowskian etc. Second, instead of power expansion (9.6) for observable, we recommend to use nonpower functional ones over particular functional sets ${{\cal A}_k(Q^2)}$, ${{\mathfrak A}_k(s)}...$ related by suitable integral transformations. We remind that use of this modified prescription results in a better correspondence of reanalyzed low energy data with the high energy ones.
hep-ph/0511266
Emmanuel Lipmanov
E. M. Lipmanov
On lepton flavor mass-degeneracy-deviation hierarchies and QD-neutrino mass
29 pages, footnote corrected, some phrases corrected
null
null
null
hep-ph
null
Two guiding new phenomenological flavor and flavor-electroweak ideas are expounded in this paper: (I) Oppositeness relation between neutrino and Charged Lepton Mass-Degeneracy-Deviation quantities. With inputs from the mass and neutrino oscillation data, it enables two independent estimations of the neutrino masses m =(0.11-0.30)eV and m =(0.11-0.16) eV. Small value of the neutrino oscillation hierarchy parameter is a consistency condition. (II) Essential connection between lepton mass hierarchies and low energy electroweak coupling constants. It enables an independent estimation of the QD-neutrino mass m = (0.11-0.14) eV, and renders three sequential charged lepton copies into one flavor system with the elementary charge encoded in the three-flavor mass hierarchy. An exact relation between the fine structure constant at Q2=0 and the experimental charged lepton mass-ratio parameter exp(-5) is observed. Experimental evidence is suggesting that this parameter has physical meaning of a dimensionless universal parameter that links flavor and electroweak quantities in accord with the guiding idea (II).
[ { "created": "Wed, 23 Nov 2005 00:25:21 GMT", "version": "v1" }, { "created": "Mon, 5 Dec 2005 19:55:39 GMT", "version": "v2" } ]
2007-05-23
[ [ "Lipmanov", "E. M.", "" ] ]
Two guiding new phenomenological flavor and flavor-electroweak ideas are expounded in this paper: (I) Oppositeness relation between neutrino and Charged Lepton Mass-Degeneracy-Deviation quantities. With inputs from the mass and neutrino oscillation data, it enables two independent estimations of the neutrino masses m =(0.11-0.30)eV and m =(0.11-0.16) eV. Small value of the neutrino oscillation hierarchy parameter is a consistency condition. (II) Essential connection between lepton mass hierarchies and low energy electroweak coupling constants. It enables an independent estimation of the QD-neutrino mass m = (0.11-0.14) eV, and renders three sequential charged lepton copies into one flavor system with the elementary charge encoded in the three-flavor mass hierarchy. An exact relation between the fine structure constant at Q2=0 and the experimental charged lepton mass-ratio parameter exp(-5) is observed. Experimental evidence is suggesting that this parameter has physical meaning of a dimensionless universal parameter that links flavor and electroweak quantities in accord with the guiding idea (II).
hep-ph/9803305
Sven Bergmann
Sven Bergmann, Alex Kagan
Z-induced FCNCs and their effects on Neutrino Oscillations
23 pages (including 5 eps-figures), Latex; references [29-34] were added to the revised version
Nucl.Phys.B538:368-386,1999
10.1016/S0550-3213(98)00686-5
WIS-98/4/MAR-DPP
hep-ph
null
Adding singlet neutrinos to the standard model spectrum in general gives rise to Z-induced flavor-changing neutral currents. We study the impact of these currents on matter-induced neutrino oscillations in the sun and in supernovae. While the effects for solar neutrinos are negligible, dramatic effects are possible for supernova neutrinos.
[ { "created": "Wed, 11 Mar 1998 16:42:37 GMT", "version": "v1" }, { "created": "Tue, 31 Mar 1998 11:03:11 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bergmann", "Sven", "" ], [ "Kagan", "Alex", "" ] ]
Adding singlet neutrinos to the standard model spectrum in general gives rise to Z-induced flavor-changing neutral currents. We study the impact of these currents on matter-induced neutrino oscillations in the sun and in supernovae. While the effects for solar neutrinos are negligible, dramatic effects are possible for supernova neutrinos.
hep-ph/0608056
Bertram Klein
L. Jendges (1), B. Klein (2), H.-J. Pirner (1 and 3), K. Schwenzer (4) ((1) Institute for Theoretical Physics, University of Heidelberg, (2) GSI, Darmstadt, (3) Max-Planck-Institut fuer Kernphysik, Heidelberg, (4) Institute for Physics, University of Graz)
Chiral Expansion from Renormalization Group Flow Equations
31 pages, 6 figures, revtex 4
null
null
null
hep-ph
null
We explore the influence of the current quark mass on observables in the low energy regime of hadronic interactions within a renormalization group analysis of the Nambu-Jona-Lasinio model in its bosonized form. We derive current quark mass expansions for the pion decay constant and the pion mass, and we recover analytically the universal logarithmic dependence. A numerical solution of the renormalization group flow equations enables us to determine effective low energy constants from the model. We find values consistent with the phenomenological estimates used in chiral perturbation theory.
[ { "created": "Fri, 4 Aug 2006 14:06:58 GMT", "version": "v1" } ]
2007-05-23
[ [ "Jendges", "L.", "", "1 and 3" ], [ "Klein", "B.", "", "1 and 3" ], [ "Pirner", "H. -J.", "", "1 and 3" ], [ "Schwenzer", "K.", "" ] ]
We explore the influence of the current quark mass on observables in the low energy regime of hadronic interactions within a renormalization group analysis of the Nambu-Jona-Lasinio model in its bosonized form. We derive current quark mass expansions for the pion decay constant and the pion mass, and we recover analytically the universal logarithmic dependence. A numerical solution of the renormalization group flow equations enables us to determine effective low energy constants from the model. We find values consistent with the phenomenological estimates used in chiral perturbation theory.
1704.03412
Ismail Zahed
Yizhuang Liu and Ismail Zahed
Heavy Baryons and their Exotics from Instantons in Holographic QCD
11 pages, 1 figure. arXiv admin note: text overlap with arXiv:1611.03757
null
10.1103/PhysRevD.95.116012
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use a variant of the $D4$-$D8$ construction that includes two chiral and one heavy meson, to describe heavy-light baryons and their exotics as heavy mesons bound to a flavor instanton in bulk. At strong coupling, the heavy meson is shown to {\it always bind} in the form of a flavor instanton zero mode in the fundamental representation. The ensuing instanton moduli for the heavy baryons exhibits both chiral and heavy quark symmetry. We detail how to quantize it, and derive model independent mass relations for heavy bayons with a single-heavy quark in leading order, in overall agreement with the reported baryonic spectra with one charm or bottom. We also discuss the low-lying masses and quantum assignments for the even and odd parity states, some of which are yet to be observed. We extend our analysis to double-heavy pentaquarks with hidden charm and bottom. In leading order, we find a pair of doube-heavy iso-doublets with $IJ^\pi=\frac 12 {\frac 12}^-, \frac 12 {\frac 32}^-$ assignments for all heavy flavor combinations. We also find five new Delta-like pentaquark states with $IJ^\pi=\frac 32 {\frac 12}^-, \frac 32 {\frac 32}^-, \frac 32 {\frac 52}^-$ assignments for both charm and bottom.
[ { "created": "Tue, 11 Apr 2017 16:56:52 GMT", "version": "v1" }, { "created": "Wed, 12 Apr 2017 20:08:47 GMT", "version": "v2" }, { "created": "Fri, 21 Apr 2017 13:27:32 GMT", "version": "v3" }, { "created": "Wed, 26 Apr 2017 23:49:08 GMT", "version": "v4" } ]
2017-08-02
[ [ "Liu", "Yizhuang", "" ], [ "Zahed", "Ismail", "" ] ]
We use a variant of the $D4$-$D8$ construction that includes two chiral and one heavy meson, to describe heavy-light baryons and their exotics as heavy mesons bound to a flavor instanton in bulk. At strong coupling, the heavy meson is shown to {\it always bind} in the form of a flavor instanton zero mode in the fundamental representation. The ensuing instanton moduli for the heavy baryons exhibits both chiral and heavy quark symmetry. We detail how to quantize it, and derive model independent mass relations for heavy bayons with a single-heavy quark in leading order, in overall agreement with the reported baryonic spectra with one charm or bottom. We also discuss the low-lying masses and quantum assignments for the even and odd parity states, some of which are yet to be observed. We extend our analysis to double-heavy pentaquarks with hidden charm and bottom. In leading order, we find a pair of doube-heavy iso-doublets with $IJ^\pi=\frac 12 {\frac 12}^-, \frac 12 {\frac 32}^-$ assignments for all heavy flavor combinations. We also find five new Delta-like pentaquark states with $IJ^\pi=\frac 32 {\frac 12}^-, \frac 32 {\frac 32}^-, \frac 32 {\frac 52}^-$ assignments for both charm and bottom.
2011.01212
Marco Fedele
Marco Ciuchini, Marco Fedele, Enrico Franco, Ayan Paul, Luca Silvestrini and Mauro Valli
Lessons from the $B^{0,+}\to K^{*0,+}\mu^+\mu^-$ angular analyses
References added, typos fixed, conclusions unchanged. 7 pages, 3 figures, 1 table
Phys. Rev. D 103, 015030 (2021)
10.1103/PhysRevD.103.015030
DESY 20-190, HU-EP-20/30, TTP20-037, P3H-20-064, UCI-TR 2020-18
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform an analysis within the Standard Model of $B^{0,+} \to K^{*0,+} \mu^+ \mu^-$ decays in light of the recent measurements from the LHCb experiment, showing that new data strengthen the need for sizable hadronic contributions and correlations among them. We then extend our analysis to New Physics via the Standard Model Effective Theory, and carry out a state-of-the-art fit of available $b \to s \ell^+ \ell^-$ data, including possible hadronic contributions. We find the case of a fully left-handed operator standing out as the simplest scenario with a significance of almost $6\sigma$.
[ { "created": "Mon, 2 Nov 2020 18:57:51 GMT", "version": "v1" }, { "created": "Thu, 12 Nov 2020 19:46:22 GMT", "version": "v2" } ]
2021-02-03
[ [ "Ciuchini", "Marco", "" ], [ "Fedele", "Marco", "" ], [ "Franco", "Enrico", "" ], [ "Paul", "Ayan", "" ], [ "Silvestrini", "Luca", "" ], [ "Valli", "Mauro", "" ] ]
We perform an analysis within the Standard Model of $B^{0,+} \to K^{*0,+} \mu^+ \mu^-$ decays in light of the recent measurements from the LHCb experiment, showing that new data strengthen the need for sizable hadronic contributions and correlations among them. We then extend our analysis to New Physics via the Standard Model Effective Theory, and carry out a state-of-the-art fit of available $b \to s \ell^+ \ell^-$ data, including possible hadronic contributions. We find the case of a fully left-handed operator standing out as the simplest scenario with a significance of almost $6\sigma$.
1803.10242
Alfredo Urbano
Christian Gross, Antonello Polosa, Alessandro Strumia, Alfredo Urbano, Wei Xue
Dark Matter in the Standard Model?
31 pages, 11 figures. v2: final version to appear on PRD; added comments about arXiv:1805.03723
Phys. Rev. D 98, 063005 (2018)
10.1103/PhysRevD.98.063005
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We critically reexamine two possible Dark Matter candidate within the Standard Model. First, we consider the $uuddss$ exa-quark. Its QCD binding energy could be large enough to make it (quasi) stable. We show that the cosmological Dark Matter abundance is reproduced thermally if its mass is 1.2 GeV. However, we also find that such mass is excluded by the stability of Oxygen nuclei. Second, we consider the possibility that the instability in the Higgs potential leads to the formation of primordial black holes while avoiding vacuum decay during inflation. We show that the non-minimal Higgs coupling to gravity must be as small as allowed by quantum corrections, $|\xi_H| < 0.01$. Even so, one must assume that the Universe survived in $e^{120}$ independent regions to fluctuations that lead to vacuum decay with probability 1/2 each.
[ { "created": "Tue, 27 Mar 2018 18:00:07 GMT", "version": "v1" }, { "created": "Mon, 3 Sep 2018 06:47:21 GMT", "version": "v2" } ]
2018-09-19
[ [ "Gross", "Christian", "" ], [ "Polosa", "Antonello", "" ], [ "Strumia", "Alessandro", "" ], [ "Urbano", "Alfredo", "" ], [ "Xue", "Wei", "" ] ]
We critically reexamine two possible Dark Matter candidate within the Standard Model. First, we consider the $uuddss$ exa-quark. Its QCD binding energy could be large enough to make it (quasi) stable. We show that the cosmological Dark Matter abundance is reproduced thermally if its mass is 1.2 GeV. However, we also find that such mass is excluded by the stability of Oxygen nuclei. Second, we consider the possibility that the instability in the Higgs potential leads to the formation of primordial black holes while avoiding vacuum decay during inflation. We show that the non-minimal Higgs coupling to gravity must be as small as allowed by quantum corrections, $|\xi_H| < 0.01$. Even so, one must assume that the Universe survived in $e^{120}$ independent regions to fluctuations that lead to vacuum decay with probability 1/2 each.
1809.06985
David R. Entem
D.R. Entem, P.G. Ortega, J. Segovia, F. Fern\'andez
Heavy mesons in the Quark Model
Contribution to the Proceedings of the 15th International Workshop on Meson Physics - MESON2018
null
10.1051/epjconf/201919901012
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Since the discovery of the $J/\psi$, the quark model was very successful in describing the spectrum and properties of heavy mesons including only $q\bar q$ components. However since 2003, with the discovery of the $X(3872)$, many states that can not be accommodated on the naive quark model have been discovered, and they made unavoidable to include higher Fock components on the heavy meson states. We will give an overview of the success of the quark model for heavy mesons and point some of the states that are likely to be more complicated structures such as meson-meson molecules.
[ { "created": "Wed, 19 Sep 2018 02:17:49 GMT", "version": "v1" } ]
2019-02-20
[ [ "Entem", "D. R.", "" ], [ "Ortega", "P. G.", "" ], [ "Segovia", "J.", "" ], [ "Fernández", "F.", "" ] ]
Since the discovery of the $J/\psi$, the quark model was very successful in describing the spectrum and properties of heavy mesons including only $q\bar q$ components. However since 2003, with the discovery of the $X(3872)$, many states that can not be accommodated on the naive quark model have been discovered, and they made unavoidable to include higher Fock components on the heavy meson states. We will give an overview of the success of the quark model for heavy mesons and point some of the states that are likely to be more complicated structures such as meson-meson molecules.
hep-ph/0512088
HockSeng Goh
Z. Chacko, Hock-Seng Goh (Arizona U.), Roni Harnik (SLAC & Stanford U.)
A Twin Higgs Model from Left-Right Symmetry
9 pages, 1 figure
JHEP 0601 (2006) 108
10.1088/1126-6708/2006/01/108
SLAC-PUB-11595
hep-ph
null
We present twin Higgs models based on the extension of the Standard Model to left-right symmetry that protect the weak scale against radiative corrections up to scales of order 5 TeV. In the ultra-violet the Higgs sector of these theories respects an approximate global symmetry, in addition to the discrete parity symmetry characteristic of left-right symmetric models. The Standard Model Higgs field emerges as the pseudo-Goldstone boson associated with the breaking of the global symmetry. The parity symmetry tightly constrains the form of radiative corrections to the Higgs potential, allowing natural electroweak breaking. The minimal model predicts a rich spectrum of exotic particles that will be accessible to upcoming experiments, and which are necessary for the cancellation of one-loop quadratic divergences. These include right-handed gauge bosons with masses not to exceed a few TeV and a pair of vector-like quarks with masses of order several hundred GeV.
[ { "created": "Wed, 7 Dec 2005 18:50:18 GMT", "version": "v1" } ]
2009-11-11
[ [ "Chacko", "Z.", "", "Arizona U." ], [ "Goh", "Hock-Seng", "", "Arizona U." ], [ "Harnik", "Roni", "", "SLAC & Stanford\n U." ] ]
We present twin Higgs models based on the extension of the Standard Model to left-right symmetry that protect the weak scale against radiative corrections up to scales of order 5 TeV. In the ultra-violet the Higgs sector of these theories respects an approximate global symmetry, in addition to the discrete parity symmetry characteristic of left-right symmetric models. The Standard Model Higgs field emerges as the pseudo-Goldstone boson associated with the breaking of the global symmetry. The parity symmetry tightly constrains the form of radiative corrections to the Higgs potential, allowing natural electroweak breaking. The minimal model predicts a rich spectrum of exotic particles that will be accessible to upcoming experiments, and which are necessary for the cancellation of one-loop quadratic divergences. These include right-handed gauge bosons with masses not to exceed a few TeV and a pair of vector-like quarks with masses of order several hundred GeV.
1803.07224
Fukuko Yuasa
H Daisaka, N Nakasato, T Ishikawa, F Yuasa, K Nitadori
A development of an accelerator board dedicated for multi-precision arithmetic operations and its application to Feynman loop integrals II
7 pages, 4 figures, in proceedings of the 18th International Workshop on Advanced Computing and Analysis Techniques in Physics Research (ACAT 2017)
null
null
null
hep-ph physics.comp-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Evaluation of a wide variety of Feynman diagrams with multi-loop integrals and physical parameters and its comparison with high energy experiments are expected to investigate new physics beyond the Standard Model. We have been developing a direct computation method of multi-loop integrals of Feynman diagrams. One of features of our method is that we adopt the double exponential rule for numerical integrations which enables us to evaluate loop integrals with boundary singularities. Another feature is that in order to accelerate the numerical integrations with multi-precision calculations, we develop an accelerator system with Field Programmable Gate Array boards on which processing elements with dedicated logic for quadruple/hexuple/octuple precision arithmetic operations are implemented. In addition, we also develop a programming interface designed for easy use of the system. The development is continued for practical use of the system. We present the current development of our system, and the numerical results of higher-loop diagrams performed using our system.
[ { "created": "Tue, 20 Mar 2018 02:38:08 GMT", "version": "v1" } ]
2018-03-21
[ [ "Daisaka", "H", "" ], [ "Nakasato", "N", "" ], [ "Ishikawa", "T", "" ], [ "Yuasa", "F", "" ], [ "Nitadori", "K", "" ] ]
Evaluation of a wide variety of Feynman diagrams with multi-loop integrals and physical parameters and its comparison with high energy experiments are expected to investigate new physics beyond the Standard Model. We have been developing a direct computation method of multi-loop integrals of Feynman diagrams. One of features of our method is that we adopt the double exponential rule for numerical integrations which enables us to evaluate loop integrals with boundary singularities. Another feature is that in order to accelerate the numerical integrations with multi-precision calculations, we develop an accelerator system with Field Programmable Gate Array boards on which processing elements with dedicated logic for quadruple/hexuple/octuple precision arithmetic operations are implemented. In addition, we also develop a programming interface designed for easy use of the system. The development is continued for practical use of the system. We present the current development of our system, and the numerical results of higher-loop diagrams performed using our system.
0906.3773
Yoshiharu Kawamura
Yoshiharu Kawamura
Misleading Coupling Unification and Lifshitz Type Gauge Theory
15 pages, 1 figure, two footnotes with references added, typos corrected
Prog.Theor.Phys.122:831-845,2010
10.1143/PTP.122.831
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new grand unification scenario for ensuring proton stability. Our scenario is based on the idea that the proton decay problem is an artificial one, which is caused from the identification of the gauge coupling unification scale with the grand unification scale or the grand unified symmetry breaking scale. We discuss a Lifshitz type gauge theory as a candidate to realize our scenario.
[ { "created": "Sat, 20 Jun 2009 03:32:24 GMT", "version": "v1" }, { "created": "Fri, 26 Jun 2009 08:25:44 GMT", "version": "v2" }, { "created": "Wed, 15 Jul 2009 06:42:46 GMT", "version": "v3" }, { "created": "Mon, 10 Aug 2009 07:07:41 GMT", "version": "v4" }, { "created": "Fri, 14 Aug 2009 01:27:51 GMT", "version": "v5" } ]
2010-01-15
[ [ "Kawamura", "Yoshiharu", "" ] ]
We propose a new grand unification scenario for ensuring proton stability. Our scenario is based on the idea that the proton decay problem is an artificial one, which is caused from the identification of the gauge coupling unification scale with the grand unification scale or the grand unified symmetry breaking scale. We discuss a Lifshitz type gauge theory as a candidate to realize our scenario.
1208.2784
Adam Martin
R. Fok, Graham D. Kribs, Adam Martin, Yuhsin Tsai
Electroweak Baryogenesis in R-symmetric Supersymmetry
17 pages, 8 figures
null
10.1103/PhysRevD.87.055018
FERMILAB-PUB-12-454-T
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We demonstrate that electroweak baryogenesis can occur in a supersymmetric model with an exact R-symmetry. The minimal R-symmetric supersymmetric model contains chiral superfields in the adjoint representation, giving Dirac gaugino masses, and an additional set of "R-partner" Higgs superfields, giving R-symmetric \mu-terms. New superpotential couplings between the adjoints and the Higgs fields can simultaneously increase the strength of the electroweak phase transition and provide additional tree-level contributions to the lightest Higgs mass. Notably, no light stop is present in this framework, and in fact, we require both stops to be above a few TeV to provide sufficient radiative corrections to the lightest Higgs mass to bring it up to 125 GeV. Large CP-violating phases in the gaugino/higgsino sector allow us to match the baryon asymmetry of the Universe with no constraints from electric dipole moments due to R-symmetry. We briefly discuss some of the more interesting phenomenology, particularly of the of the lightest CP-odd scalar.
[ { "created": "Tue, 14 Aug 2012 04:55:49 GMT", "version": "v1" } ]
2013-03-27
[ [ "Fok", "R.", "" ], [ "Kribs", "Graham D.", "" ], [ "Martin", "Adam", "" ], [ "Tsai", "Yuhsin", "" ] ]
We demonstrate that electroweak baryogenesis can occur in a supersymmetric model with an exact R-symmetry. The minimal R-symmetric supersymmetric model contains chiral superfields in the adjoint representation, giving Dirac gaugino masses, and an additional set of "R-partner" Higgs superfields, giving R-symmetric \mu-terms. New superpotential couplings between the adjoints and the Higgs fields can simultaneously increase the strength of the electroweak phase transition and provide additional tree-level contributions to the lightest Higgs mass. Notably, no light stop is present in this framework, and in fact, we require both stops to be above a few TeV to provide sufficient radiative corrections to the lightest Higgs mass to bring it up to 125 GeV. Large CP-violating phases in the gaugino/higgsino sector allow us to match the baryon asymmetry of the Universe with no constraints from electric dipole moments due to R-symmetry. We briefly discuss some of the more interesting phenomenology, particularly of the of the lightest CP-odd scalar.
hep-ph/0108006
Shrihari Gopalakrishna
Shrihari Gopalakrishna, James Wells
Superlight gravitinos in electron-photon collisions
8 pages Added 2 terms to eqn(3) for easy reference and other minor changes to improve clarity
Phys.Lett.B518:123-127,2001
10.1016/S0370-2693(01)01038-3
LBNL-48649
hep-ph
null
Motivated by recent studies of supersymmetry in higher-dimensional spaces, we discuss the experimental signatures of a superlight gravitino, mass < 0.001 eV. We concentrate on the process (e- gamma -> selectronR gravitino) as a probe of supersymmetry, where a single heavy superpartner and a superlight gravitino are produced. The fact that there is only one heavy superpartner in the final state in this process would require a lower center-of-mass energy for on-shell production compared to conventional pair production. For instance, for a 500 GeV machine, we find that a positive signal will be found if the supersymmetry breaking scale is less than about 2 TeV. If no positive signal is found, this process puts a bound on the supersymmetry breaking scale.
[ { "created": "Wed, 1 Aug 2001 20:15:51 GMT", "version": "v1" }, { "created": "Wed, 22 Aug 2001 20:47:24 GMT", "version": "v2" } ]
2014-11-17
[ [ "Gopalakrishna", "Shrihari", "" ], [ "Wells", "James", "" ] ]
Motivated by recent studies of supersymmetry in higher-dimensional spaces, we discuss the experimental signatures of a superlight gravitino, mass < 0.001 eV. We concentrate on the process (e- gamma -> selectronR gravitino) as a probe of supersymmetry, where a single heavy superpartner and a superlight gravitino are produced. The fact that there is only one heavy superpartner in the final state in this process would require a lower center-of-mass energy for on-shell production compared to conventional pair production. For instance, for a 500 GeV machine, we find that a positive signal will be found if the supersymmetry breaking scale is less than about 2 TeV. If no positive signal is found, this process puts a bound on the supersymmetry breaking scale.
1510.00311
Stefan de Boer
Stefan de Boer and Gudrun Hiller
Flavor & new physics opportunities with rare charm decays into leptons
19 pages plus references and appendices, 5 figures; v2: $\eta^{(\prime)}$ contribution fixed, references added, conclusion unchanged; v3: typos corrected and clarifications and references added, conclusions unchanged
Phys. Rev. D 93, 074001 (2016)
10.1103/PhysRevD.93.074001
DO-TH 15/10, QFET-2015-25
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Updated standard model predictions for $D_{(s)} \to P l^+ l^-$, $l=e,\mu$, $P=\pi,K$ and inclusive decays are presented. Model-independent constraints on $|\Delta C|=|\Delta U|=1$ Wilson coefficients are worked out. New physics (NP) opportunities arise in semileptonic branching ratios for very large couplings only, however, are not excluded outside the resonance regions yet. The NP potential of resonance-assisted CP asymmetries and angular observables is worked out. Predictions are given for leptoquark models, and include lepton flavor violating and dineutrino decays. Whether NP can be seen depends on flavor patterns, and vice versa.
[ { "created": "Thu, 1 Oct 2015 16:50:31 GMT", "version": "v1" }, { "created": "Wed, 14 Oct 2015 13:37:37 GMT", "version": "v2" }, { "created": "Tue, 22 Mar 2016 16:37:18 GMT", "version": "v3" } ]
2016-04-06
[ [ "de Boer", "Stefan", "" ], [ "Hiller", "Gudrun", "" ] ]
Updated standard model predictions for $D_{(s)} \to P l^+ l^-$, $l=e,\mu$, $P=\pi,K$ and inclusive decays are presented. Model-independent constraints on $|\Delta C|=|\Delta U|=1$ Wilson coefficients are worked out. New physics (NP) opportunities arise in semileptonic branching ratios for very large couplings only, however, are not excluded outside the resonance regions yet. The NP potential of resonance-assisted CP asymmetries and angular observables is worked out. Predictions are given for leptoquark models, and include lepton flavor violating and dineutrino decays. Whether NP can be seen depends on flavor patterns, and vice versa.
1604.06161
Kunihiko Terasaki
Kunihiko Terasaki
Production of Neutral and Doubly Charged Partners of D_{s0}^+(2317) Revisited
6 pages, 1 figure
null
null
YITP-16-51
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Rates for productions of neutral and doubly charged partners of D_{s0}^+(2317) in B meson decays are studied by using a hard D meson approximation in the infinite momentum frame, and the results are of the same order of magnitude as that of D_{s0}^+(2317). Because the bottom-strange X^{+-}(5568) which can be interpreted as iso-triplet bottom partners of D_{s0}^+(2317) have recently been discovered, observations of neutral and doubly charged partners of D_{s0}^+(2317) are strongly desired.
[ { "created": "Thu, 21 Apr 2016 02:33:34 GMT", "version": "v1" } ]
2016-04-22
[ [ "Terasaki", "Kunihiko", "" ] ]
Rates for productions of neutral and doubly charged partners of D_{s0}^+(2317) in B meson decays are studied by using a hard D meson approximation in the infinite momentum frame, and the results are of the same order of magnitude as that of D_{s0}^+(2317). Because the bottom-strange X^{+-}(5568) which can be interpreted as iso-triplet bottom partners of D_{s0}^+(2317) have recently been discovered, observations of neutral and doubly charged partners of D_{s0}^+(2317) are strongly desired.
hep-ph/9912239
A. N. Mitra
A.N.Mitra
3D-4D Interlinkage Of B-S Amplitudes : Unified View Of QQbar And QQQ Dynamics
LaTex file, 37 pages
null
null
null
hep-ph
null
This article has a 3-fold objective: i) to provide a panoramic view of several types of 3D vs 4D approaches in Field Theory (Tamm-Dancoff, Bethe Salpeter Equation (BSE), Quasi-potentials, Light-Front Dynamics, etc) for strong interaction dunamics; ii) to focus on the role of the Markov-Yukawa Transversality Principle (MYTP) as a novel paradigm for an exact 3D-4D interlinkage between the corresponding BSE amplitudes; iii) Stress on a closely parallel treatment of $q{\bar q}$ and qqq BSE's stemming from a common 4-fermion Lagrangian mediated by gluon (vector)-like exchange. The two-way interlinkage offered by MYTP between the 3D and 4D BSE forms via a Lorentz-covariant 3D support to the BS kernel, gives it a unique status which distinguishes it from most other 3D approaches to strong interaction dynamics, which give at most a one-way connection. Two specific types of MYTP which provide 3D support to the BSE kernel, are considered: a) Covariant Instantaneity Ansatz (CIA); b) Covariant LF/NP ansatz (Cov.LF). Both lead to formaly identical 3D BSE reductions (thus ensuring common spectral predictions), but their 4D manifestations differ sharply: Under CIA, the 4D loop integrals suffer from Lorentz mismatch of the vertex functions, leading to ill-defined time-like momentum integrals, but Cov LF is free from this disease. Some practical uses of MYTP as a basis for evaluating various types of 4D loop integrals are outlined. PACS: 11.10 st ; 12.38 Lg ; 13.40.Fn Keywords: Tamm-Dancoff, Bethe-Salpeter, Quasi-potentials, Light-front (LF), Markov-Yukawa, 3D-4D Interlinkage, CIA, Cov-LF, Spectroscopy.
[ { "created": "Sat, 4 Dec 1999 06:45:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Mitra", "A. N.", "" ] ]
This article has a 3-fold objective: i) to provide a panoramic view of several types of 3D vs 4D approaches in Field Theory (Tamm-Dancoff, Bethe Salpeter Equation (BSE), Quasi-potentials, Light-Front Dynamics, etc) for strong interaction dunamics; ii) to focus on the role of the Markov-Yukawa Transversality Principle (MYTP) as a novel paradigm for an exact 3D-4D interlinkage between the corresponding BSE amplitudes; iii) Stress on a closely parallel treatment of $q{\bar q}$ and qqq BSE's stemming from a common 4-fermion Lagrangian mediated by gluon (vector)-like exchange. The two-way interlinkage offered by MYTP between the 3D and 4D BSE forms via a Lorentz-covariant 3D support to the BS kernel, gives it a unique status which distinguishes it from most other 3D approaches to strong interaction dynamics, which give at most a one-way connection. Two specific types of MYTP which provide 3D support to the BSE kernel, are considered: a) Covariant Instantaneity Ansatz (CIA); b) Covariant LF/NP ansatz (Cov.LF). Both lead to formaly identical 3D BSE reductions (thus ensuring common spectral predictions), but their 4D manifestations differ sharply: Under CIA, the 4D loop integrals suffer from Lorentz mismatch of the vertex functions, leading to ill-defined time-like momentum integrals, but Cov LF is free from this disease. Some practical uses of MYTP as a basis for evaluating various types of 4D loop integrals are outlined. PACS: 11.10 st ; 12.38 Lg ; 13.40.Fn Keywords: Tamm-Dancoff, Bethe-Salpeter, Quasi-potentials, Light-front (LF), Markov-Yukawa, 3D-4D Interlinkage, CIA, Cov-LF, Spectroscopy.
hep-ph/9904210
Steve King
S. F. King
Atmospheric and Solar Neutrinos from Single Right-Handed Neutrino Dominance and U(1) Family Symmetry
30 latex pages. Final version to appear in Nucl.Phys.B
Nucl.Phys.B562:57-77,1999
10.1016/S0550-3213(99)00542-8
null
hep-ph
null
We argue that in order to provide a natural explanation of both neutrino mass hierarchies and large neutrino mixing angles, as required by the atmospheric neutrino data, a single right-handed neutrino must give the dominant contribution to the 23 block of the light effective neutrino matrix, and illustrate this mechanism in the framework of models with U(1) family symmetries. Sub-dominant contributions from other right-handed neutrinos are required to give small mass splittings appropriate to the small angle MSW solution to the solar neutrino problem. We give general conditions for achieving this in the framework of U(1) family symmetry models containing arbitrary numbers of right-handed neutrinos, and show how the resulting neutrino mass hierarchies and mixing angles may be expanded in terms of the Wolfenstein parameter.
[ { "created": "Thu, 1 Apr 1999 19:47:17 GMT", "version": "v1" }, { "created": "Mon, 12 Apr 1999 11:44:22 GMT", "version": "v2" }, { "created": "Fri, 16 Apr 1999 16:53:13 GMT", "version": "v3" }, { "created": "Thu, 26 Aug 1999 15:57:47 GMT", "version": "v4" } ]
2014-11-17
[ [ "King", "S. F.", "" ] ]
We argue that in order to provide a natural explanation of both neutrino mass hierarchies and large neutrino mixing angles, as required by the atmospheric neutrino data, a single right-handed neutrino must give the dominant contribution to the 23 block of the light effective neutrino matrix, and illustrate this mechanism in the framework of models with U(1) family symmetries. Sub-dominant contributions from other right-handed neutrinos are required to give small mass splittings appropriate to the small angle MSW solution to the solar neutrino problem. We give general conditions for achieving this in the framework of U(1) family symmetry models containing arbitrary numbers of right-handed neutrinos, and show how the resulting neutrino mass hierarchies and mixing angles may be expanded in terms of the Wolfenstein parameter.
1310.6982
Alessandro Strumia
Alberto Salvio, Alessandro Strumia, Wei Xue
Thermal axion production
16 pages, 5 figures. v3: we thank Daniel Green and Benjamin Wallisch for having pointed out a numerical error in the electroweak gauge contribution in fig. 5, which has been corrected
null
10.1088/1475-7516/2014/01/011
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We reconsider thermal production of axions in the early universe, including axion couplings to all Standard Model (SM) particles. Concerning the axion coupling to gluons, we find that thermal effects enhance the axion production rate by a factor of few with respect to previous computations performed in the limit of small strong gauge coupling. Furthermore, we find that the top Yukawa coupling induces a much larger axion production rate, unless the axion couples to SM particles only via anomalies.
[ { "created": "Fri, 25 Oct 2013 17:23:11 GMT", "version": "v1" }, { "created": "Mon, 16 Dec 2013 21:21:31 GMT", "version": "v2" }, { "created": "Mon, 2 May 2016 10:01:18 GMT", "version": "v3" } ]
2016-05-03
[ [ "Salvio", "Alberto", "" ], [ "Strumia", "Alessandro", "" ], [ "Xue", "Wei", "" ] ]
We reconsider thermal production of axions in the early universe, including axion couplings to all Standard Model (SM) particles. Concerning the axion coupling to gluons, we find that thermal effects enhance the axion production rate by a factor of few with respect to previous computations performed in the limit of small strong gauge coupling. Furthermore, we find that the top Yukawa coupling induces a much larger axion production rate, unless the axion couples to SM particles only via anomalies.
1410.6282
Valentina Sadovnikova
E. G. Drukarev, M. G. Ryskin, V. A. Sadovnikova
On the loop approximation in nucleon QCD sum rules
11 pages, 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There was a general believe that the nucleon QCD sum rules which include only the quark loops and thus contain only the condensates of dimension d=3 and d=4 have only a trivial solution. We demonstrate that there is also a nontrivial solution. We show that it can be treated as the lowest order approximation to the solution which includes the higher terms of the Operator Product Expansion. Inclusion of the radiative corrections improves the convergence of the series.
[ { "created": "Thu, 23 Oct 2014 08:11:47 GMT", "version": "v1" } ]
2014-10-24
[ [ "Drukarev", "E. G.", "" ], [ "Ryskin", "M. G.", "" ], [ "Sadovnikova", "V. A.", "" ] ]
There was a general believe that the nucleon QCD sum rules which include only the quark loops and thus contain only the condensates of dimension d=3 and d=4 have only a trivial solution. We demonstrate that there is also a nontrivial solution. We show that it can be treated as the lowest order approximation to the solution which includes the higher terms of the Operator Product Expansion. Inclusion of the radiative corrections improves the convergence of the series.
1511.06002
Sven Heinemeyer
S. Heinemeyer, C. Schappacher
Neutral Higgs Boson Production at e+e- Colliders in the Complex MSSM: A Full One-Loop Analysis
34 pages, 16 figures. arXiv admin note: text overlap with arXiv:1503.02996, arXiv:1410.2787
null
10.1140/epjc/s10052-016-4038-4
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For the search for additional Higgs bosons in the Minimal Supersymmetric Standard Model (MSSM) as well as for future precision analyses in the Higgs sector a precise knowledge of their production properties is mandatory. We evaluate the cross sections for the neutral Higgs boson production at e^+e^- colliders in the MSSM with complex parameters (cMSSM). The evaluation is based on a full one-loop calculation of the production channels e^+e^- -> h_i Z, h_i gamma, h_i h_j (i,j = 1,2,3), including soft and hard QED radiation. The dependence of the Higgs boson production cross sections on the relevant cMSSM parameters is analyzed numerically. We find sizable contributions to many cross sections. They are, depending on the production channel, roughly of 10-20% of the tree-level results, but can go up to 50% or higher. The full one-loop contributions are important for a future linear e^+e^- collider such as the ILC or CLIC. There are plans to implement the evaluation of the Higgs boson production cross sections into the code FeynHiggs.
[ { "created": "Wed, 18 Nov 2015 22:17:12 GMT", "version": "v1" } ]
2016-05-25
[ [ "Heinemeyer", "S.", "" ], [ "Schappacher", "C.", "" ] ]
For the search for additional Higgs bosons in the Minimal Supersymmetric Standard Model (MSSM) as well as for future precision analyses in the Higgs sector a precise knowledge of their production properties is mandatory. We evaluate the cross sections for the neutral Higgs boson production at e^+e^- colliders in the MSSM with complex parameters (cMSSM). The evaluation is based on a full one-loop calculation of the production channels e^+e^- -> h_i Z, h_i gamma, h_i h_j (i,j = 1,2,3), including soft and hard QED radiation. The dependence of the Higgs boson production cross sections on the relevant cMSSM parameters is analyzed numerically. We find sizable contributions to many cross sections. They are, depending on the production channel, roughly of 10-20% of the tree-level results, but can go up to 50% or higher. The full one-loop contributions are important for a future linear e^+e^- collider such as the ILC or CLIC. There are plans to implement the evaluation of the Higgs boson production cross sections into the code FeynHiggs.
2212.00493
Juan M. Torres-Rincon
Juan M. Torres-Rincon
Transport coefficients of heavy mesons in a thermal medium
6 pages, 4 figures. Contribution to the proceedings of ICHEP 2022 conference, see https://www.ichep2022.it/
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have investigated the many-body equations of $D$ and $\bar{B}$ mesons in a thermal medium by applying an effective field theory based on chiral and heavy-quark symmetries. Exploiting these symmetries within kinetic theory, we have derived an off-shell Fokker-Planck equation which incorporates information of the full spectral functions of these states. In this contribution we present our latest results on heavy-flavor transport coefficients below the chiral restoration temperature, in both charm and bottom sectors. The calculation incorporating temperature-dependent spectral functions and interactions, together with off-shell effects, allows for an improved matching to the state-of-the-art calculations above the chiral transition temperature.
[ { "created": "Thu, 1 Dec 2022 13:43:09 GMT", "version": "v1" } ]
2022-12-02
[ [ "Torres-Rincon", "Juan M.", "" ] ]
We have investigated the many-body equations of $D$ and $\bar{B}$ mesons in a thermal medium by applying an effective field theory based on chiral and heavy-quark symmetries. Exploiting these symmetries within kinetic theory, we have derived an off-shell Fokker-Planck equation which incorporates information of the full spectral functions of these states. In this contribution we present our latest results on heavy-flavor transport coefficients below the chiral restoration temperature, in both charm and bottom sectors. The calculation incorporating temperature-dependent spectral functions and interactions, together with off-shell effects, allows for an improved matching to the state-of-the-art calculations above the chiral transition temperature.
hep-ph/9809386
Du Dong-Sheng
Youshan Dai, Dongsheng Du
CP Violation in Two-Body Hadronic Decays of $B_c$ Meson
19 pages, 3 figures, corrected some typos and sentences
Eur.Phys.J.C9:557-564,1999
10.1007/s100529900073
null
hep-ph
null
Using the next-to-leading order low energy effective Hamiltonian, the CP asymmetries for the $B_{c}$ meson decays into meson pair are calculated in the spectator approximation. We do not compute the hadronic matrix elements directly, instead, we use the amplitude ratios to estimate the CP asymmetries. This is quite,different from the previous works in the literature. The values of the momentum squared carried by the virtual particles in timelike penguin dirgrams are also carefully discussed. From our calculated results, the best decay modes to observe CP violation in $B_{c}$ decays would be $B_{c}^-\to{\bar D}^{*0}K^{*-}$, ${\bar D}^{0}K^{*-}$, ${\bar D}^{*0} K^{-}$, ${\bar D}^{0}K^{-}$ and $B_{c}^-\to{\eta}_{c}D^{-}$, which need about $10^8$ of $B_{c}^{\pm}$ events in experiment.
[ { "created": "Tue, 15 Sep 1998 03:34:47 GMT", "version": "v1" }, { "created": "Wed, 16 Dec 1998 06:56:06 GMT", "version": "v2" } ]
2011-09-13
[ [ "Dai", "Youshan", "" ], [ "Du", "Dongsheng", "" ] ]
Using the next-to-leading order low energy effective Hamiltonian, the CP asymmetries for the $B_{c}$ meson decays into meson pair are calculated in the spectator approximation. We do not compute the hadronic matrix elements directly, instead, we use the amplitude ratios to estimate the CP asymmetries. This is quite,different from the previous works in the literature. The values of the momentum squared carried by the virtual particles in timelike penguin dirgrams are also carefully discussed. From our calculated results, the best decay modes to observe CP violation in $B_{c}$ decays would be $B_{c}^-\to{\bar D}^{*0}K^{*-}$, ${\bar D}^{0}K^{*-}$, ${\bar D}^{*0} K^{-}$, ${\bar D}^{0}K^{-}$ and $B_{c}^-\to{\eta}_{c}D^{-}$, which need about $10^8$ of $B_{c}^{\pm}$ events in experiment.
2312.04977
Hongxia Huang
Ye Yan, Hongxia Huang, Xinmei Zhu and Jialun Ping
Prediction of $P_{cc}$ states in quark model
13 pages, 6 figures. arXiv admin note: text overlap with arXiv:2309.15380
null
null
null
hep-ph hep-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
Inspired by the observation of hidden-charm pentaquark $P_c$ and $P_{cs}$ states by the LHCb Collaboration, we explore the $qqc\bar{c}c$ ($q~=~u$ or $d$) pentaquark systems in the quark delocalization color screening model. The interaction between baryons and mesons and the influence of channel coupling are studied in this work. Three compact $qqc\bar{c}c$ pentaquark states are obtained, whose masses are 5259 MeV with $I(J^P)$ = $0(1/2^-)$, 5396 MeV with $I(J^P)$ = $1(1/2^-)$, and 5465 MeV with $I(J^P)$ = $1(3/2^-)$. Two molecular states are obtained, which are $I(J^P)$ = $0(1/2^-)$ $\Lambda_c J/\psi$ with 5367 MeV and $I(J^P)$ = $0(5/2^-)$ $\Xi_{cc}^* \bar{D}^*$ with 5690 MeV. These predicted states may provide important information for future experimental search.
[ { "created": "Fri, 8 Dec 2023 11:19:06 GMT", "version": "v1" } ]
2023-12-11
[ [ "Yan", "Ye", "" ], [ "Huang", "Hongxia", "" ], [ "Zhu", "Xinmei", "" ], [ "Ping", "Jialun", "" ] ]
Inspired by the observation of hidden-charm pentaquark $P_c$ and $P_{cs}$ states by the LHCb Collaboration, we explore the $qqc\bar{c}c$ ($q~=~u$ or $d$) pentaquark systems in the quark delocalization color screening model. The interaction between baryons and mesons and the influence of channel coupling are studied in this work. Three compact $qqc\bar{c}c$ pentaquark states are obtained, whose masses are 5259 MeV with $I(J^P)$ = $0(1/2^-)$, 5396 MeV with $I(J^P)$ = $1(1/2^-)$, and 5465 MeV with $I(J^P)$ = $1(3/2^-)$. Two molecular states are obtained, which are $I(J^P)$ = $0(1/2^-)$ $\Lambda_c J/\psi$ with 5367 MeV and $I(J^P)$ = $0(5/2^-)$ $\Xi_{cc}^* \bar{D}^*$ with 5690 MeV. These predicted states may provide important information for future experimental search.
1810.12525
Zhen Fang
Zhen Fang, Yue-Liang Wu, Lin Zhang
Chiral phase transition and QCD phase diagram from AdS/QCD
null
Phys. Rev. D 99, 034028 (2019)
10.1103/PhysRevD.99.034028
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the chemical potential effects on the chiral phase transition in a simply improved soft-wall AdS/QCD model, which can realize consistently the properties of linear confinement and spontaneous chiral symmetry breaking. The $\mu-T$ phase diagrams with both zero and physical quark masses have been obtained from this model. For the case of physical quark mass, the chiral transition has a crossover behavior at low chemical potential. With the increase of the chemical potential $\mu$, the critical temperature $T_c$ descends towards zero, and the crossover transition turns into a first-order one at some intermediate value of $\mu$, which implies that a critical end point naturally exists in this improved soft-wall model. All these features agree with our current perspective on the QCD phase diagram.
[ { "created": "Tue, 30 Oct 2018 04:40:37 GMT", "version": "v1" } ]
2019-03-06
[ [ "Fang", "Zhen", "" ], [ "Wu", "Yue-Liang", "" ], [ "Zhang", "Lin", "" ] ]
We study the chemical potential effects on the chiral phase transition in a simply improved soft-wall AdS/QCD model, which can realize consistently the properties of linear confinement and spontaneous chiral symmetry breaking. The $\mu-T$ phase diagrams with both zero and physical quark masses have been obtained from this model. For the case of physical quark mass, the chiral transition has a crossover behavior at low chemical potential. With the increase of the chemical potential $\mu$, the critical temperature $T_c$ descends towards zero, and the crossover transition turns into a first-order one at some intermediate value of $\mu$, which implies that a critical end point naturally exists in this improved soft-wall model. All these features agree with our current perspective on the QCD phase diagram.
1208.3244
Qiaoli Yang
H. Tam and Q. Yang
Detecting Sub-eV Scale Physics by Interferometry
4 pages, no figures. Contributed to the 8th Patras Workshop on Axions, WIMPs and WISPs, Chicago, July 18-22, 2012; A summary of authors' previous paper: arXiv:1107.1712
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new interferometry-based experiment to detect sub-eV scale particles such as axion-like particles (ALPs).
[ { "created": "Wed, 15 Aug 2012 23:01:28 GMT", "version": "v1" }, { "created": "Fri, 17 Aug 2012 20:41:49 GMT", "version": "v2" }, { "created": "Wed, 12 Dec 2012 07:49:48 GMT", "version": "v3" } ]
2012-12-13
[ [ "Tam", "H.", "" ], [ "Yang", "Q.", "" ] ]
We propose a new interferometry-based experiment to detect sub-eV scale particles such as axion-like particles (ALPs).
2112.09103
Santiago Tanco
Anibal D. Medina, Nicol\'as I. Mileo, Alejandro Szynkman, Santiago A. Tanco
The Elusive Muonic WIMP
26 pages, 7 figures; Published version
Phys. Rev. D 106, 075018 (2022)
10.1103/PhysRevD.106.075018
null
hep-ph astro-ph.HE hep-ex
http://creativecommons.org/licenses/by/4.0/
The Weakly Interacting Massive Particle (WIMP) paradigm is one of the most popular scenarios for Dark Matter (DM) theories that however is strongly constrained, in particular by direct detection experiments. We stick with the WIMP hypothesis and consider a Dirac fermion candidate for DM that interacts with the Standard Model (SM) via a spin-1 $Z'$, arising from the spontaneous breaking of an Abelian $U(1)'_{\mu}$ gauge symmetry, under which only second generation leptons and the DM are appropriately charged. Due to the charge assignment, the model is gauge anomalous and can only be interpreted as an effective field theory (EFT) at low energy. The $Z'$ couples at tree level only to the vector DM current, to the axial muon current and to left-handed muonic neutrinos, so the WIMP-nucleon cross section is beyond the experimental reach of spin-independent (SI) direct detection searches. We study the current bounds on this model coming from direct and indirect detection of DM, collider searches, contributions to $(g-2)_{\mu}$ and to neutrino trident production. We find that large regions of the parameter space remains to be explored. In the context of LHC searches, we study the impact of a muon-exclusive signal region for the $3\mu$ + ${E}^{{\rm miss}}_T$ channel with an invariant mass window around $m_{Z'}$. We show that this search can significantly improve the current collider bounds. Finally, from the anomalous nature of our EFT, there remain at low energy triboson anomalous interactions between the $Z'$ and the electroweak (EW) SM gauge bosons. We explore the possibilities of probing these interactions at the LHC and at a 100 TeV proton collider finding it extremely challenging. On the other hand, for a muon collider the resonant channel $\mu^{+}\mu^{-}\to Z'\to ZZ$ could be discovered in the most promising scenario with luminosity of $\mathcal{O}({\rm few}\; 10)$ ${\rm fb}^{-1}$.
[ { "created": "Thu, 16 Dec 2021 18:36:53 GMT", "version": "v1" }, { "created": "Fri, 21 Oct 2022 16:37:07 GMT", "version": "v2" } ]
2022-10-24
[ [ "Medina", "Anibal D.", "" ], [ "Mileo", "Nicolás I.", "" ], [ "Szynkman", "Alejandro", "" ], [ "Tanco", "Santiago A.", "" ] ]
The Weakly Interacting Massive Particle (WIMP) paradigm is one of the most popular scenarios for Dark Matter (DM) theories that however is strongly constrained, in particular by direct detection experiments. We stick with the WIMP hypothesis and consider a Dirac fermion candidate for DM that interacts with the Standard Model (SM) via a spin-1 $Z'$, arising from the spontaneous breaking of an Abelian $U(1)'_{\mu}$ gauge symmetry, under which only second generation leptons and the DM are appropriately charged. Due to the charge assignment, the model is gauge anomalous and can only be interpreted as an effective field theory (EFT) at low energy. The $Z'$ couples at tree level only to the vector DM current, to the axial muon current and to left-handed muonic neutrinos, so the WIMP-nucleon cross section is beyond the experimental reach of spin-independent (SI) direct detection searches. We study the current bounds on this model coming from direct and indirect detection of DM, collider searches, contributions to $(g-2)_{\mu}$ and to neutrino trident production. We find that large regions of the parameter space remains to be explored. In the context of LHC searches, we study the impact of a muon-exclusive signal region for the $3\mu$ + ${E}^{{\rm miss}}_T$ channel with an invariant mass window around $m_{Z'}$. We show that this search can significantly improve the current collider bounds. Finally, from the anomalous nature of our EFT, there remain at low energy triboson anomalous interactions between the $Z'$ and the electroweak (EW) SM gauge bosons. We explore the possibilities of probing these interactions at the LHC and at a 100 TeV proton collider finding it extremely challenging. On the other hand, for a muon collider the resonant channel $\mu^{+}\mu^{-}\to Z'\to ZZ$ could be discovered in the most promising scenario with luminosity of $\mathcal{O}({\rm few}\; 10)$ ${\rm fb}^{-1}$.
1608.00336
Kazuya Mameda
Shu Ebihara, Kenji Fukushima, Kazuya Mameda
Boundary effects and gapped dispersion in rotating fermionic matter
6 pages, 1 figure
Phys. Lett. B764, 94 (2017)
10.1016/j.physletb.2016.11.010
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the importance of boundary effects on fermionic matter in a rotating frame. By explicit calculations at zero temperature we show that the scalar condensate of fermion and anti-fermion cannot be modified by the rotation once the boundary condition is properly implemented. The situation is qualitatively changed at finite temperature and/or in the presence of a sufficiently strong magnetic field that supersedes the boundary effects. Therefore, to establish an interpretation of the rotation as an effective chemical potential, it is crucial to consider further environmental effects such as the finite temperature and magnetic field.
[ { "created": "Mon, 1 Aug 2016 07:05:13 GMT", "version": "v1" }, { "created": "Wed, 10 Aug 2016 17:43:00 GMT", "version": "v2" }, { "created": "Sun, 13 Nov 2016 14:25:18 GMT", "version": "v3" } ]
2016-11-23
[ [ "Ebihara", "Shu", "" ], [ "Fukushima", "Kenji", "" ], [ "Mameda", "Kazuya", "" ] ]
We discuss the importance of boundary effects on fermionic matter in a rotating frame. By explicit calculations at zero temperature we show that the scalar condensate of fermion and anti-fermion cannot be modified by the rotation once the boundary condition is properly implemented. The situation is qualitatively changed at finite temperature and/or in the presence of a sufficiently strong magnetic field that supersedes the boundary effects. Therefore, to establish an interpretation of the rotation as an effective chemical potential, it is crucial to consider further environmental effects such as the finite temperature and magnetic field.
hep-ph/9504434
Carl Schmidt
Carl R. Schmidt
Top Quark Production and Decay at Next-to-leading Order in $e^+e^-$ Annihilation
44 pages, LaTex, 10 embedded postscript figures, tarred and uuencoded in separate file
Phys.Rev. D54 (1996) 3250-3265
10.1103/PhysRevD.54.3250
SCIPP 95/14
hep-ph
null
We study the effects of QCD corrections to the process $e^+e^-\rightarrow t\bar t+X\rightarrow b\ell^+\nu \bar b\ell^-\bar \nu+X$ above threshold. We show how to treat consistently to ${\cal O}(\alpha_s)$ the gluon radiation in both the production and the decay of the top quarks, while maintaining all angular correlations in the event. At this order there is an ambiguity in the event reconstruction whenever a real gluon occurs in the final state. We study the effects of this ambiguity on the top mass and helicity angle distributions. For a top mass of 175 GeV and collider energy of 400 GeV the gluon radiation is emitted predominantly in the decay of the top quarks.
[ { "created": "Mon, 1 May 1995 03:49:38 GMT", "version": "v1" } ]
2009-10-28
[ [ "Schmidt", "Carl R.", "" ] ]
We study the effects of QCD corrections to the process $e^+e^-\rightarrow t\bar t+X\rightarrow b\ell^+\nu \bar b\ell^-\bar \nu+X$ above threshold. We show how to treat consistently to ${\cal O}(\alpha_s)$ the gluon radiation in both the production and the decay of the top quarks, while maintaining all angular correlations in the event. At this order there is an ambiguity in the event reconstruction whenever a real gluon occurs in the final state. We study the effects of this ambiguity on the top mass and helicity angle distributions. For a top mass of 175 GeV and collider energy of 400 GeV the gluon radiation is emitted predominantly in the decay of the top quarks.
hep-ph/9808350
Heinrich Paes
H.V. Klapdor-Kleingrothaus, H. P\"as
New physics potential of double beta decay and dark matter search
Talk presented by H. Paes at the at the 6th Symp. on Particles, Strings and Cosmology (PASCOS'98), Boston, March 1998; 11 pages, 5 figures included, needs sprocl.sty
null
null
null
hep-ph
null
The search for neutrinoless double beta decay and WIMP dark matter has a broad potential to test particle physics beyond the standard model. During the last years, the analysis of various contributions to the double beta decay rate by the Heidelberg group led, besides the most restrictive limit on the effective Majorana neutrino mass, to bounds on left-right-symmetric models, leptoquarks and supersymmetry. In a general framework bounds on arbitrary lepton number violating theories can be derived. Using double beta technology for direct dark matter detection, stringent limits on the spin-independent WIMP--nucleon interaction have been obtained. These results deduced from the Heidelberg-Moscow double beta decay experiment are reviewed. Also an outlook on the future of double beta decay and dark matter search, the GENIUS proposal, is given.
[ { "created": "Tue, 18 Aug 1998 15:33:45 GMT", "version": "v1" } ]
2007-05-23
[ [ "Klapdor-Kleingrothaus", "H. V.", "" ], [ "Päs", "H.", "" ] ]
The search for neutrinoless double beta decay and WIMP dark matter has a broad potential to test particle physics beyond the standard model. During the last years, the analysis of various contributions to the double beta decay rate by the Heidelberg group led, besides the most restrictive limit on the effective Majorana neutrino mass, to bounds on left-right-symmetric models, leptoquarks and supersymmetry. In a general framework bounds on arbitrary lepton number violating theories can be derived. Using double beta technology for direct dark matter detection, stringent limits on the spin-independent WIMP--nucleon interaction have been obtained. These results deduced from the Heidelberg-Moscow double beta decay experiment are reviewed. Also an outlook on the future of double beta decay and dark matter search, the GENIUS proposal, is given.
2203.01685
Sanjin Beni\'c
Sanjin Beni\'c, Oscar Garcia-Montero, Anton Perkov
Isolated photon-hadron production in high energy $pp$ and $pA$ collisions at RHIC and LHC
minor corrections, matches the published version
null
10.1103/PhysRevD.105.114052
ZTF-EP-22-01
hep-ph
http://creativecommons.org/licenses/by/4.0/
We compute the isolated photon production in association with a charged hadron at mid rapidity in $pp$ and $pA$ based on the Color Glass Condensate (CGC) framework of high energy QCD where, for the first time, we incorporate the Sudakov effect of soft gluon emissions. Our results are based on the leading order $q g \to q \gamma$ channel in the CGC framework and confronted with the recent data from RHIC and LHC concerning the angular distributions and out-of-plane transverse momentum distributions. We find that, while the CGC computation alone results in too narrow distributions, with the help of the Sudakov effect, we can get a satisfactory description of the data. With this as a benchmark, we provide predictions for the magnitude of the nuclear effect brought by the phenomena of gluon saturation in the CGC.
[ { "created": "Thu, 3 Mar 2022 12:47:55 GMT", "version": "v1" }, { "created": "Sun, 3 Jul 2022 02:34:36 GMT", "version": "v2" } ]
2022-07-05
[ [ "Benić", "Sanjin", "" ], [ "Garcia-Montero", "Oscar", "" ], [ "Perkov", "Anton", "" ] ]
We compute the isolated photon production in association with a charged hadron at mid rapidity in $pp$ and $pA$ based on the Color Glass Condensate (CGC) framework of high energy QCD where, for the first time, we incorporate the Sudakov effect of soft gluon emissions. Our results are based on the leading order $q g \to q \gamma$ channel in the CGC framework and confronted with the recent data from RHIC and LHC concerning the angular distributions and out-of-plane transverse momentum distributions. We find that, while the CGC computation alone results in too narrow distributions, with the help of the Sudakov effect, we can get a satisfactory description of the data. With this as a benchmark, we provide predictions for the magnitude of the nuclear effect brought by the phenomena of gluon saturation in the CGC.
1405.3831
Xiang Liu
Li-Ping He, Dian-Yong Chen, Xiang Liu and Takayuki Matsuki
Prediction of a missing higher charmonium around 4.26 GeV in $J/\psi$ family
5 pages, 5 figures and 1 table. More discussions added. Accepted by Eur. Phys. J. C
Eur. Phys. J. C 74, 3208 (2014)
10.1140/epjc/s10052-014-3208-5
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inspired by the similarity of mass gaps of $J/\psi$ and $\Upsilon$ families, the prediction of missing higher charmonium with mass $4263$ MeV and very narrow width is made. In addition, the properties of two charmonium-like states, $X(3940)$ and $X(4160)$, and charmonium $\psi(4415)$ are discussed. Here, $X(3940)$ as $\eta_c(3S)$ is established while the explanation of $X(4160)$ to be $\eta_c(4S)$ is fully excluded and $\eta_c(4S)$ is typically a very narrow state. These predictions can be accessible at BESIII, Belle and BelleII in near future.
[ { "created": "Thu, 15 May 2014 13:02:18 GMT", "version": "v1" }, { "created": "Tue, 25 Nov 2014 12:53:22 GMT", "version": "v2" }, { "created": "Wed, 10 Dec 2014 02:28:27 GMT", "version": "v3" } ]
2014-12-11
[ [ "He", "Li-Ping", "" ], [ "Chen", "Dian-Yong", "" ], [ "Liu", "Xiang", "" ], [ "Matsuki", "Takayuki", "" ] ]
Inspired by the similarity of mass gaps of $J/\psi$ and $\Upsilon$ families, the prediction of missing higher charmonium with mass $4263$ MeV and very narrow width is made. In addition, the properties of two charmonium-like states, $X(3940)$ and $X(4160)$, and charmonium $\psi(4415)$ are discussed. Here, $X(3940)$ as $\eta_c(3S)$ is established while the explanation of $X(4160)$ to be $\eta_c(4S)$ is fully excluded and $\eta_c(4S)$ is typically a very narrow state. These predictions can be accessible at BESIII, Belle and BelleII in near future.
0906.3789
Pierpaolo Mastrolia
Pierpaolo Mastrolia
Unitarity-Cuts and Berry's Phase
3 pages, 1 figure
Lett.Math.Phys.91:199-204,2010
10.1007/s11005-010-0370-z
CERN-PH-TH-2009-104
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Elaborating on the observation that two-particle unitarity-cuts of scattering amplitudes can be computed by applying Stokes' Theorem, we relate the Optical Theorem to the Berry Phase, showing how the imaginary part of arbitrary one-loop Feynman amplitudes can be interpreted as the flux of a complex 2-form.
[ { "created": "Mon, 22 Jun 2009 18:59:35 GMT", "version": "v1" } ]
2010-02-11
[ [ "Mastrolia", "Pierpaolo", "" ] ]
Elaborating on the observation that two-particle unitarity-cuts of scattering amplitudes can be computed by applying Stokes' Theorem, we relate the Optical Theorem to the Berry Phase, showing how the imaginary part of arbitrary one-loop Feynman amplitudes can be interpreted as the flux of a complex 2-form.
1905.08190
Oleksandr Sobol Dr.
O.O. Sobol
Electrical conductivity of hot Abelian plasma with scalar charge carriers
36 pages, 2 figures, 4 tables
Phys. Rev. D 100, 056012 (2019)
10.1103/PhysRevD.100.056012
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the electrical conductivity of hot Abelian plasma containing scalar charge carriers in the leading logarithmic order in coupling constant $\alpha$ using the Boltzmann kinetic equation. The leading contribution to the collision integral is due to the M{\o}ller and Bhabha scattering of scalar particles with a singular cross section in the region of small momentum transfer. Regularizing this singularity by taking into account the hard thermal loop corrections to the propagators of intermediate particles, we derive the second order differential equation which determines the kinetic function. We solve this equation numerically and also use a variational approach in order to find a simple analytical formula for the conductivity. It has the standard parametric dependence on the coupling constant $\sigma\approx 2.38\, T/(\alpha \log\alpha^{-1})$ with the prefactor taking a somewhat lower value compared to the fermionic case. Finally, we consider the general case of hot Abelian plasma with an arbitrary number of scalar and fermionic particle species and derive the simple analytical formula for its conductivity.
[ { "created": "Mon, 20 May 2019 16:06:32 GMT", "version": "v1" }, { "created": "Thu, 19 Sep 2019 16:00:10 GMT", "version": "v2" } ]
2019-09-20
[ [ "Sobol", "O. O.", "" ] ]
We study the electrical conductivity of hot Abelian plasma containing scalar charge carriers in the leading logarithmic order in coupling constant $\alpha$ using the Boltzmann kinetic equation. The leading contribution to the collision integral is due to the M{\o}ller and Bhabha scattering of scalar particles with a singular cross section in the region of small momentum transfer. Regularizing this singularity by taking into account the hard thermal loop corrections to the propagators of intermediate particles, we derive the second order differential equation which determines the kinetic function. We solve this equation numerically and also use a variational approach in order to find a simple analytical formula for the conductivity. It has the standard parametric dependence on the coupling constant $\sigma\approx 2.38\, T/(\alpha \log\alpha^{-1})$ with the prefactor taking a somewhat lower value compared to the fermionic case. Finally, we consider the general case of hot Abelian plasma with an arbitrary number of scalar and fermionic particle species and derive the simple analytical formula for its conductivity.
1903.06927
Xin-Qiang Li
Quan-Yi Hu, Xin-Qiang Li, Ya-Dong Yang, and Min-Di Zheng
$B_{s(d)}-\bar{B}_{s(d)}$ Mixing and $B_s\to\mu^+\mu^-$ Decay in the NMSSM with the Flavour Expansion Theorem
48 pages, 7 figures, and 2 tables; More discussions and references added, final version to be published in JHEP
null
10.1007/JHEP06(2019)133
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, motivated by the observation that the Standard Model predictions are now above the experimental data for the mass difference $\Delta M_{s(d)}$, we perform a detailed study of $B_{s(d)}-\bar{B}_{s(d)}$ mixing and $B_s\to\mu^+\mu^-$ decay in the $\mathbb{Z}_3$-invariant NMSSM with non-minimal flavour violation, using the recently developed procedure based on the Flavour Expansion Theorem, with which one can perform a purely algebraic mass-insertion expansion of an amplitude written in the mass eigenstate basis without performing any diagrammatic calculations in the interaction/flavour basis. Specifically, we consider the finite orders of mass insertions for neutralinos but the general orders for squarks and charginos, under two sets of assumptions for the squark flavour structures (\textit{i.e.}, while the flavour-conserving off-diagonal element $\delta_{33}^\text{LR}$ is kept in both of these two sectors, only the flavour-violating off-diagonal elements $\delta_{23}^\text{LL}$ and $\delta_{i3}^\text{RR}$ ($i=1,2$) are kept in the \text{LL} and \text{RR} sectors, respectively). Our analytic results are then expressed directly in terms of the initial Lagrangian parameters in the interaction/flavour basis, making it easy to impose the experimental bounds on them. It is found numerically that the NMSSM effects with the above two assumptions for the squark flavour structures can accommodate the observed deviation for $\Delta M_{s(d)}$, while complying with the experimental constraints from the branching ratios of $B_s\to \mu^+ \mu^-$ and $B\to X_s\gamma$ decays.
[ { "created": "Sat, 16 Mar 2019 14:08:09 GMT", "version": "v1" }, { "created": "Wed, 26 Jun 2019 01:07:44 GMT", "version": "v2" } ]
2022-10-12
[ [ "Hu", "Quan-Yi", "" ], [ "Li", "Xin-Qiang", "" ], [ "Yang", "Ya-Dong", "" ], [ "Zheng", "Min-Di", "" ] ]
In this paper, motivated by the observation that the Standard Model predictions are now above the experimental data for the mass difference $\Delta M_{s(d)}$, we perform a detailed study of $B_{s(d)}-\bar{B}_{s(d)}$ mixing and $B_s\to\mu^+\mu^-$ decay in the $\mathbb{Z}_3$-invariant NMSSM with non-minimal flavour violation, using the recently developed procedure based on the Flavour Expansion Theorem, with which one can perform a purely algebraic mass-insertion expansion of an amplitude written in the mass eigenstate basis without performing any diagrammatic calculations in the interaction/flavour basis. Specifically, we consider the finite orders of mass insertions for neutralinos but the general orders for squarks and charginos, under two sets of assumptions for the squark flavour structures (\textit{i.e.}, while the flavour-conserving off-diagonal element $\delta_{33}^\text{LR}$ is kept in both of these two sectors, only the flavour-violating off-diagonal elements $\delta_{23}^\text{LL}$ and $\delta_{i3}^\text{RR}$ ($i=1,2$) are kept in the \text{LL} and \text{RR} sectors, respectively). Our analytic results are then expressed directly in terms of the initial Lagrangian parameters in the interaction/flavour basis, making it easy to impose the experimental bounds on them. It is found numerically that the NMSSM effects with the above two assumptions for the squark flavour structures can accommodate the observed deviation for $\Delta M_{s(d)}$, while complying with the experimental constraints from the branching ratios of $B_s\to \mu^+ \mu^-$ and $B\to X_s\gamma$ decays.
hep-ph/0604243
B. L. G. Bakker
A.M.Badalian (Institute of Theoretical and Experimental Physics, Moscow, Russia.) B.L.G.Bakker (Department of Physics and Astronomy, Vrije Universiteit, Amsterdam, The Netherlands)
Higher $\eta_c(nS)$ and $\eta_b (nS)$ mesons
23 pages
null
10.1134/S1063778807100134
null
hep-ph
null
The hyperfine splittings in heavy quarkonia are studied in a model-independent way using the experimental data on di-electron widths. Relativistic correlations are taken into account together with the smearing of the spin-spin interaction. The radius of smearing is fixed by the known $J/\psi-\eta_c(1S)$ and $\psi(2S)-\eta'_c(2S)$ splittings and appears to be small, $r_{ss} \cong 0.06$ fm. Nevertheless, even with such a small radius an essential suppression of the hyperfine splittings ($\sim 50%)$ is observed in bottomonium. For the $nS~ b\bar b$ states $(n=1,2,...,6)$ we predict the values (in MeV) 28, 12, 10, 6, 6, and 3, respectively. For the $3S$ and $4S$ charmonium states the splittings 16(2) MeV and 12(4) MeV are obtained.
[ { "created": "Thu, 27 Apr 2006 14:46:46 GMT", "version": "v1" } ]
2009-11-11
[ [ "Badalian", "A. M.", "", "Institute of Theoretical and Experimental Physics,\n Moscow, Russia." ], [ "Bakker", "B. L. G.", "", "Department of Physics and Astronomy, Vrije\n Universiteit, Amsterdam, The Netherlands" ] ]
The hyperfine splittings in heavy quarkonia are studied in a model-independent way using the experimental data on di-electron widths. Relativistic correlations are taken into account together with the smearing of the spin-spin interaction. The radius of smearing is fixed by the known $J/\psi-\eta_c(1S)$ and $\psi(2S)-\eta'_c(2S)$ splittings and appears to be small, $r_{ss} \cong 0.06$ fm. Nevertheless, even with such a small radius an essential suppression of the hyperfine splittings ($\sim 50%)$ is observed in bottomonium. For the $nS~ b\bar b$ states $(n=1,2,...,6)$ we predict the values (in MeV) 28, 12, 10, 6, 6, and 3, respectively. For the $3S$ and $4S$ charmonium states the splittings 16(2) MeV and 12(4) MeV are obtained.
hep-ph/0610321
Bjorn Garbrecht
Bjorn Garbrecht and Thomas Konstandin
Hybrid Inflation Exit through Tunneling
17 pages, 2 figures
JHEP 0701:033,2007
10.1088/1126-6708/2007/01/033
MAN/HEP/2006/29
hep-ph
null
For hybrid inflationary potentials, we derive the tunneling rate from field configurations along the flat direction towards the waterfall regime. This process competes with the classically rolling evolution of the scalar fields and needs to be strongly subdominant for phenomenologically viable models. Tunneling may exclude models with a mass scale below 10^12 GeV, but can be suppressed by small values of the coupling constants. We find that tunneling is negligible for those models, which do not require fine tuning in order to cancel radiative corrections, in particular for GUT-scale SUSY inflation. In contrast, electroweak scale hybrid inflation is not viable, unless the inflaton-waterfall field coupling is smaller than approximately 10^-11.
[ { "created": "Tue, 24 Oct 2006 18:44:30 GMT", "version": "v1" } ]
2010-10-27
[ [ "Garbrecht", "Bjorn", "" ], [ "Konstandin", "Thomas", "" ] ]
For hybrid inflationary potentials, we derive the tunneling rate from field configurations along the flat direction towards the waterfall regime. This process competes with the classically rolling evolution of the scalar fields and needs to be strongly subdominant for phenomenologically viable models. Tunneling may exclude models with a mass scale below 10^12 GeV, but can be suppressed by small values of the coupling constants. We find that tunneling is negligible for those models, which do not require fine tuning in order to cancel radiative corrections, in particular for GUT-scale SUSY inflation. In contrast, electroweak scale hybrid inflation is not viable, unless the inflaton-waterfall field coupling is smaller than approximately 10^-11.
2111.04514
Hua-Xing Chen
Hua-Xing Chen, Wei Chen and Shi-Lin Zhu
New hadron configuration: The double-gluon hybrid state
5 pages, 3 figures, 1 table, revised version to be published in PRD
Phys. Rev. D 105, L051501 (2022)
10.1103/PhysRevD.105.L051501
null
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
This is the first study on the double-gluon hybrid, which consists of one valence quark and one valence antiquark together with two valence gluons. We concentrate on the one with the exotic quantum number $J^{PC} = 2^{+-}$ that conventional $\bar q q$ mesons can not reach. We apply QCD sum rule method to evaluate its mass to be $2.26^{+0.20}_{-0.25}$ GeV, and study its possible decay patterns. Especially, its three-meson decay patterns are generally not suppressed severely compared to two-meson decay patterns, so the $S$-wave three-meson decay channels $f_1\omega\pi/f_1\rho\pi$ can be useful in identifying its nature, which is of particular importance to the direct test of QCD in the low energy sector.
[ { "created": "Mon, 8 Nov 2021 13:57:18 GMT", "version": "v1" }, { "created": "Thu, 11 Nov 2021 09:51:31 GMT", "version": "v2" }, { "created": "Fri, 4 Mar 2022 01:08:46 GMT", "version": "v3" } ]
2022-03-07
[ [ "Chen", "Hua-Xing", "" ], [ "Chen", "Wei", "" ], [ "Zhu", "Shi-Lin", "" ] ]
This is the first study on the double-gluon hybrid, which consists of one valence quark and one valence antiquark together with two valence gluons. We concentrate on the one with the exotic quantum number $J^{PC} = 2^{+-}$ that conventional $\bar q q$ mesons can not reach. We apply QCD sum rule method to evaluate its mass to be $2.26^{+0.20}_{-0.25}$ GeV, and study its possible decay patterns. Especially, its three-meson decay patterns are generally not suppressed severely compared to two-meson decay patterns, so the $S$-wave three-meson decay channels $f_1\omega\pi/f_1\rho\pi$ can be useful in identifying its nature, which is of particular importance to the direct test of QCD in the low energy sector.
hep-ph/9404337
Hiroyuki Siomi
H. Shiomi and T. Hatsuda
Vector Mesons in Nuclear Medium -- an Effective Lagrangian Approach --
LaTeX 9 pages, 3 figures are available on request, report UTHEP-276
Phys.Lett. B334 (1994) 281-286
10.1016/0370-2693(94)90688-2
null
hep-ph nucl-th
null
Effective masses of $\rho$ and $\omega$ mesons in nuclear medium are studied in a hadronic effective theory. Both the pole position and the screening mass decrease in nuclear matter due to the polarization of the nucleon Dirac sea. The physical origin of the decrease is a reduction of the wave function renormalization constant induced by the tensor (vector) interaction of the $\rho$ ($\omega$) with the nucleon. Relation to the results of the QCD sum rules is also discussed.
[ { "created": "Tue, 26 Apr 1994 06:02:02 GMT", "version": "v1" } ]
2009-10-28
[ [ "Shiomi", "H.", "" ], [ "Hatsuda", "T.", "" ] ]
Effective masses of $\rho$ and $\omega$ mesons in nuclear medium are studied in a hadronic effective theory. Both the pole position and the screening mass decrease in nuclear matter due to the polarization of the nucleon Dirac sea. The physical origin of the decrease is a reduction of the wave function renormalization constant induced by the tensor (vector) interaction of the $\rho$ ($\omega$) with the nucleon. Relation to the results of the QCD sum rules is also discussed.
0806.3140
Qiang Zhao
Yuan-Jiang Zhang, Qiang Zhao, and Cong-Feng Qiao
Possible contributions to $e^+e^- \to J/\psi + \eta_c$ due to intermediate meson rescatterings
revised version to appear in Phys. Rev. D
Phys.Rev.D78:054014,2008
10.1103/PhysRevD.78.054014
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inspired by the obvious discrepancies between experiment and non-relativistic QCD (NRQCD) studies of $e^+ e^-\to J/\psi+\eta_c$ at $\sqrt{s}\simeq 10.6$ GeV, we investigate contributions from intermediate meson loops as long-range interaction transitions to this process. The intermediate meson loops include $D\bar D(\bar D^\ast)$, $D\bar D^\ast(D {or} D^\ast)$, $D^\ast \bar D^\ast(D)$ and corresponding $D_s$ intermediate mesons. With the constraints from experimental data on the vertex couplings, we find that the intermediate meson loops account for $2.7\sim 6.7 fb$ of the cross sections within a reasonable range of cut-off energies of the factor parameter. We also investigate contributions from the absorptive part and find that it accounts for approximately $0.58\sim 1.38 fb$. These results imply that contributions from long-range interaction transitions may still play a role in such an energy region.
[ { "created": "Thu, 19 Jun 2008 07:13:52 GMT", "version": "v1" }, { "created": "Thu, 26 Jun 2008 07:11:03 GMT", "version": "v2" }, { "created": "Wed, 27 Aug 2008 02:26:26 GMT", "version": "v3" } ]
2009-01-09
[ [ "Zhang", "Yuan-Jiang", "" ], [ "Zhao", "Qiang", "" ], [ "Qiao", "Cong-Feng", "" ] ]
Inspired by the obvious discrepancies between experiment and non-relativistic QCD (NRQCD) studies of $e^+ e^-\to J/\psi+\eta_c$ at $\sqrt{s}\simeq 10.6$ GeV, we investigate contributions from intermediate meson loops as long-range interaction transitions to this process. The intermediate meson loops include $D\bar D(\bar D^\ast)$, $D\bar D^\ast(D {or} D^\ast)$, $D^\ast \bar D^\ast(D)$ and corresponding $D_s$ intermediate mesons. With the constraints from experimental data on the vertex couplings, we find that the intermediate meson loops account for $2.7\sim 6.7 fb$ of the cross sections within a reasonable range of cut-off energies of the factor parameter. We also investigate contributions from the absorptive part and find that it accounts for approximately $0.58\sim 1.38 fb$. These results imply that contributions from long-range interaction transitions may still play a role in such an energy region.
1510.02797
Marek Lewicki
Zygmunt Lalak, Marek Lewicki and Pawe{\l} Olszewski
Standard Model vacuum stability in the presence of gauge invariant nonrenormalizable operators
Talk given at 18th International Conference `From the Planck Scale to the Electroweak Scale', 25-29 May 2015, Ioannina, Greece
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Analysis of the Standard Model effective potential can reveal certain properties of the UV completion of SM. We discuss the issue of stability of the SM potential after inclusion of new nonrenormalizable interactions. We present the map of lifetimes resulting from different configurations of the new operators. The key result is proof of gauge independence of our results after inclusion of nonrenormalizable operators. We also discuss the consequences of RGE improvement of the potential.
[ { "created": "Fri, 9 Oct 2015 20:03:41 GMT", "version": "v1" } ]
2015-10-13
[ [ "Lalak", "Zygmunt", "" ], [ "Lewicki", "Marek", "" ], [ "Olszewski", "Paweł", "" ] ]
Analysis of the Standard Model effective potential can reveal certain properties of the UV completion of SM. We discuss the issue of stability of the SM potential after inclusion of new nonrenormalizable interactions. We present the map of lifetimes resulting from different configurations of the new operators. The key result is proof of gauge independence of our results after inclusion of nonrenormalizable operators. We also discuss the consequences of RGE improvement of the potential.
0910.5237
Hai-Yang Cheng
Hai-Yang Cheng, Chun-Khiang Chua
QCD Factorization for Charmless Hadronic B_s Decays Revisited
38 pages
Phys.Rev.D80:114026,2009
10.1103/PhysRevD.80.114026
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Branching fractions and CP-violating asymmetries of charmless $\bar B_s\to PP, VP, VV$ decays (P and V denoting pseudoscalar and vector mesons, respectively) are re-examined in the framework of QCD factorization (QCDF). We take into account subleading power corrections to the penguin annihilation topology and to color-suppressed tree amplitudes that are crucial for resolving the CP puzzles and rate deficit problems with penguin-dominated two-body decays and color-suppressed tree-dominated $\pi^0\pi^0$ and $\rho^0\pi^0$ modes in the $B_{u,d}$ sector. Many of the $B_s\to h_1h_2$ decays can be related to $B_d\to h_1h_2$ ones via U-spin or SU(3) symmetry. Some useful model-independent relations can be derived and tested. Mixing-induced CP asymmetries for many of the penguin-dominated decays are predicted to be very small in the standard model. They are sensitive to New Physics and offer rich possibilities of new discoveries. Measurements of direct CP-violating asymmetries can be used to discriminate QCDF from other competing approaches such as pQCD and soft-collinear effective theory.
[ { "created": "Tue, 27 Oct 2009 20:38:30 GMT", "version": "v1" } ]
2010-01-07
[ [ "Cheng", "Hai-Yang", "" ], [ "Chua", "Chun-Khiang", "" ] ]
Branching fractions and CP-violating asymmetries of charmless $\bar B_s\to PP, VP, VV$ decays (P and V denoting pseudoscalar and vector mesons, respectively) are re-examined in the framework of QCD factorization (QCDF). We take into account subleading power corrections to the penguin annihilation topology and to color-suppressed tree amplitudes that are crucial for resolving the CP puzzles and rate deficit problems with penguin-dominated two-body decays and color-suppressed tree-dominated $\pi^0\pi^0$ and $\rho^0\pi^0$ modes in the $B_{u,d}$ sector. Many of the $B_s\to h_1h_2$ decays can be related to $B_d\to h_1h_2$ ones via U-spin or SU(3) symmetry. Some useful model-independent relations can be derived and tested. Mixing-induced CP asymmetries for many of the penguin-dominated decays are predicted to be very small in the standard model. They are sensitive to New Physics and offer rich possibilities of new discoveries. Measurements of direct CP-violating asymmetries can be used to discriminate QCDF from other competing approaches such as pQCD and soft-collinear effective theory.
1605.04402
Teruyuki Kitabayashi
Teruyuki Kitabayashi and Masaki Yasu\`e
Maximal CP Violation in Minimal Seesaw Model
9 pages, no figure,version accepted for publication in Physical Review D
Phys. Rev. D 94, 075020 (2016)
10.1103/PhysRevD.94.075020
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the minimal seesaw model, we derive required constraints on Dirac neutrino masses inducing maximal CP violation in neutrino oscillations. If the maximal atmospheric neutrino mixing is further assumed, Dirac neutrino masses are uniquely determined to respect $\mu$-$\tau$ flavored CP symmetry for neutrinos.
[ { "created": "Sat, 14 May 2016 10:01:25 GMT", "version": "v1" }, { "created": "Thu, 17 Nov 2016 08:36:59 GMT", "version": "v2" } ]
2016-11-18
[ [ "Kitabayashi", "Teruyuki", "" ], [ "Yasuè", "Masaki", "" ] ]
In the minimal seesaw model, we derive required constraints on Dirac neutrino masses inducing maximal CP violation in neutrino oscillations. If the maximal atmospheric neutrino mixing is further assumed, Dirac neutrino masses are uniquely determined to respect $\mu$-$\tau$ flavored CP symmetry for neutrinos.
hep-ph/9606430
Thomas Meissner
Thomas Meissner and Michael Frank
Low-Energy QCD: Chiral Coefficients, UA(1)-Breaking and the Quark-Quark Interaction
Contributed Paper at PANIC 96, 2 pages, LATEX, uses sprocl.sty and axodraw.sty
null
null
null
hep-ph
null
A detailed investigation of the low-energy chiral expansion is presented within a model truncation of QCD. The model dependence of the chiral coefficients is tested for several forms of the quark-quark interaction by varying the form of the running coupling in the infrared region. Furthermore we demonstrate how the UA(1)$ anomaly and a mass for the eta' can arise in this approach.
[ { "created": "Tue, 25 Jun 1996 16:10:36 GMT", "version": "v1" } ]
2007-05-23
[ [ "Meissner", "Thomas", "" ], [ "Frank", "Michael", "" ] ]
A detailed investigation of the low-energy chiral expansion is presented within a model truncation of QCD. The model dependence of the chiral coefficients is tested for several forms of the quark-quark interaction by varying the form of the running coupling in the infrared region. Furthermore we demonstrate how the UA(1)$ anomaly and a mass for the eta' can arise in this approach.
hep-ph/0604097
Boris Kopeliovich
B.Z. Kopeliovich, I.K. Potashnikova, Ivan Schmidt
Diffraction in QCD
Based on the lecture given by B.K. at I LAWHEP, Porto Alegre, Brazil, December 1-3, 2005
Braz.J.Phys.37:473-483,2007
10.1590/S0103-97332007000400002
USM-TH 183
hep-ph
null
This lecture presents a short review of the main features of diffractive processes and QCD inspired models. It includes the following topics: (1) Quantum mechanics of diffraction: general properties; (2) Color dipole description of diffraction; (3) Color transparency; (4) Soft diffraction in hard reactions: DIS, Drell-Yan, Higgs production; (5) Why Pomerons interact weakly; (6) Small gluonic spots in the proton; (7) Diffraction near the unitarity bound: the Goulianos-Schlein "puzzle"; (8) Diffraction on nuclei: diffractive Color Glass; (9) CGC and gluon shadowing.
[ { "created": "Tue, 11 Apr 2006 17:27:53 GMT", "version": "v1" } ]
2011-08-04
[ [ "Kopeliovich", "B. Z.", "" ], [ "Potashnikova", "I. K.", "" ], [ "Schmidt", "Ivan", "" ] ]
This lecture presents a short review of the main features of diffractive processes and QCD inspired models. It includes the following topics: (1) Quantum mechanics of diffraction: general properties; (2) Color dipole description of diffraction; (3) Color transparency; (4) Soft diffraction in hard reactions: DIS, Drell-Yan, Higgs production; (5) Why Pomerons interact weakly; (6) Small gluonic spots in the proton; (7) Diffraction near the unitarity bound: the Goulianos-Schlein "puzzle"; (8) Diffraction on nuclei: diffractive Color Glass; (9) CGC and gluon shadowing.
0904.2646
Fernand Renard M
M. Beccaria, F.M. Renard, C. Verzegnassi
A peculiar property of SUSY amplitudes at high energy
23 pqges, 4 eps figures
Int.J.Mod.Phys.A24:6123-6140,2009
10.1142/S0217751X09047569
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We observe that the electroweak one loop correction to the quark+gluon to quark+Higgs amplitude at high energy involves both single and quadratic logarithms of the energy in the SM case but only quadratic logarithms in the MSSM case. We explore the origin of this special SUSY cancellation, both in a diagrammatic way and through the splitting+Parameter Renormalization procedure. We show that it is not an accident but a remarkableand general SUSY property of the renormalized Higgs-fermion-fermion and Higgsino-sfermion-fermion vertices which directly reflects in such processes, for example in $bg\to tH^-$, $bg\to bH^0$, $bg\to bh^0$, $bg\to bA^0$, and through equivalence in $bg\to tW^-_{long}$, $bg\to bZ_{long}$, as well as in $bg\to \tilde{t}\chi^-$, $bg\to\tilde{b}\chi^0$. This simplification of the high energy behaviour (which only leaves quadratic logarithms involving pure gauge couplings without any free parameter) allows to write simple relations among these various processes which constitute genuine tests of the assumed SUSY model.
[ { "created": "Fri, 17 Apr 2009 07:22:03 GMT", "version": "v1" }, { "created": "Wed, 2 Sep 2009 10:08:05 GMT", "version": "v2" } ]
2010-01-21
[ [ "Beccaria", "M.", "" ], [ "Renard", "F. M.", "" ], [ "Verzegnassi", "C.", "" ] ]
We observe that the electroweak one loop correction to the quark+gluon to quark+Higgs amplitude at high energy involves both single and quadratic logarithms of the energy in the SM case but only quadratic logarithms in the MSSM case. We explore the origin of this special SUSY cancellation, both in a diagrammatic way and through the splitting+Parameter Renormalization procedure. We show that it is not an accident but a remarkableand general SUSY property of the renormalized Higgs-fermion-fermion and Higgsino-sfermion-fermion vertices which directly reflects in such processes, for example in $bg\to tH^-$, $bg\to bH^0$, $bg\to bh^0$, $bg\to bA^0$, and through equivalence in $bg\to tW^-_{long}$, $bg\to bZ_{long}$, as well as in $bg\to \tilde{t}\chi^-$, $bg\to\tilde{b}\chi^0$. This simplification of the high energy behaviour (which only leaves quadratic logarithms involving pure gauge couplings without any free parameter) allows to write simple relations among these various processes which constitute genuine tests of the assumed SUSY model.
0705.4357
Bodo Geyer
B.Geyer and O. Witzel
Heavy Meson Distribution Amplitudes of Definite Geometric Twist with Contribution of 3-Particle Distribution Amplitudes
24 pages
Phys.Rev.D76:074022,2007
10.1103/PhysRevD.76.074022
HU-EP-07/19, SFB/CPP-07-23
hep-ph
null
Under the constraints of HQET the equations of motion of heavy meson distribution amplitudes of definite geometric twist, using the knowledge of their off-cone structure, are reformulated as a set of algebraic equations. Together with equations due to various Dirac structures various relations between the (sets of) independent two- and three particle distribution amplitudes of definite geometric twist are derived and presented using both the notion of (double) Mellin moments and re-summed non-local distribution amplitudes. Resolving these relations for the independent two-particle moments in terms of three-particle double moments we confirmed the representation of $\Phi_{\pm|n}$ by Kawamura et al. (Phys. Lett. B \bf{523} (2001) 111).
[ { "created": "Wed, 30 May 2007 09:00:21 GMT", "version": "v1" }, { "created": "Thu, 5 Jul 2007 09:27:51 GMT", "version": "v2" } ]
2008-11-26
[ [ "Geyer", "B.", "" ], [ "Witzel", "O.", "" ] ]
Under the constraints of HQET the equations of motion of heavy meson distribution amplitudes of definite geometric twist, using the knowledge of their off-cone structure, are reformulated as a set of algebraic equations. Together with equations due to various Dirac structures various relations between the (sets of) independent two- and three particle distribution amplitudes of definite geometric twist are derived and presented using both the notion of (double) Mellin moments and re-summed non-local distribution amplitudes. Resolving these relations for the independent two-particle moments in terms of three-particle double moments we confirmed the representation of $\Phi_{\pm|n}$ by Kawamura et al. (Phys. Lett. B \bf{523} (2001) 111).
hep-ph/9707219
Oleg Selugin
S.V. Goloskokov, S.P. Kuleshov, O.V. Selyugin
Elastic nucleon scattering at small angles at LHC energies
LaTex file, with 3 figs (file.ps)
null
null
null
hep-ph
null
Predictions of the elastic proton-proton cross sections at energies of LHC are calculate on the base of the high energy dynamical model. The growth of $ds/dt$ at fixed transfer momenta are shown. The form of eikonal of elastic hadron scattering at super high energies is discussed.
[ { "created": "Wed, 2 Jul 1997 09:28:51 GMT", "version": "v1" } ]
2007-05-23
[ [ "Goloskokov", "S. V.", "" ], [ "Kuleshov", "S. P.", "" ], [ "Selyugin", "O. V.", "" ] ]
Predictions of the elastic proton-proton cross sections at energies of LHC are calculate on the base of the high energy dynamical model. The growth of $ds/dt$ at fixed transfer momenta are shown. The form of eikonal of elastic hadron scattering at super high energies is discussed.
hep-ph/0012180
Gilberto Tavares Velasco
F. Larios, M.A. Perez, G. Tavares-Velasco and J.J. Toscano
Trilinear Neutral Gauge Boson Couplings in Effective Theories
21 pages, 2 figures, RevTex formatted
Phys.Rev. D63 (2001) 113014
10.1103/PhysRevD.63.113014
null
hep-ph
null
We list all the lowest dimension effective operators inducing off-shell trilinear neutral gauge boson couplings Z-Z-Photon, Z-Photon-Photon, and ZZZ within the effective Lagrangian approach, both in the linear and nonlinear realizations of the SU(2)_{L} X U(1)_Y gauge symmetry. In the linear scenario we find that these couplings can be generated only by dimension eight operators necessarily including the Higgs boson field, whereas in the nonlinear case they are induced by dimension six operators. We consider the impact of these couplings on some precision measurements such as the magnetic and electric dipole moments of fermions, as well as the Z boson rare decay Z -> neutrino+antineutrino+ photon. If the underlying new physics is of a decoupling nature, it is not expected that trilinear neutral gauge boson couplings may affect considerably any of these observables. On the contrary, it is just in the nonlinear scenario where these couplings have the more promising prospects of being perceptible through high precision experiments.
[ { "created": "Thu, 14 Dec 2000 22:12:38 GMT", "version": "v1" } ]
2009-10-31
[ [ "Larios", "F.", "" ], [ "Perez", "M. A.", "" ], [ "Tavares-Velasco", "G.", "" ], [ "Toscano", "J. J.", "" ] ]
We list all the lowest dimension effective operators inducing off-shell trilinear neutral gauge boson couplings Z-Z-Photon, Z-Photon-Photon, and ZZZ within the effective Lagrangian approach, both in the linear and nonlinear realizations of the SU(2)_{L} X U(1)_Y gauge symmetry. In the linear scenario we find that these couplings can be generated only by dimension eight operators necessarily including the Higgs boson field, whereas in the nonlinear case they are induced by dimension six operators. We consider the impact of these couplings on some precision measurements such as the magnetic and electric dipole moments of fermions, as well as the Z boson rare decay Z -> neutrino+antineutrino+ photon. If the underlying new physics is of a decoupling nature, it is not expected that trilinear neutral gauge boson couplings may affect considerably any of these observables. On the contrary, it is just in the nonlinear scenario where these couplings have the more promising prospects of being perceptible through high precision experiments.