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1010.3406
Reinier Adelhart Toorop de
Reinier de Adelhart Toorop
The interplay between grand unified and flavour symmetries in a Pati-Salam x S4 model
To appear in the proceedings of PASCOS 2010, the 16th International Symposium on Particles, Strings and Cosmology, Valencia, Spain
J.Phys.Conf.Ser.259:012099,2010
10.1088/1742-6596/259/1/012099
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Both discrete flavour symmetries and Grand Unified symmetries explain apparent structures in the mass sector of the Standard Model. A model that combines both symmetries is therefore very appealing. We construct a model with the $S_4$ flavour symmetry and the Pati-Salam unification. We show that this model can indeed explain many observable relations between the masses of the quarks and leptons and that it is predictive in the neutrino sector. However, the combination of the two symmetries leads to new complications in the Higgs sector and in the running of the renormalisation group equations.
[ { "created": "Sun, 17 Oct 2010 12:44:37 GMT", "version": "v1" } ]
2011-01-27
[ [ "Toorop", "Reinier de Adelhart", "" ] ]
Both discrete flavour symmetries and Grand Unified symmetries explain apparent structures in the mass sector of the Standard Model. A model that combines both symmetries is therefore very appealing. We construct a model with the $S_4$ flavour symmetry and the Pati-Salam unification. We show that this model can indeed explain many observable relations between the masses of the quarks and leptons and that it is predictive in the neutrino sector. However, the combination of the two symmetries leads to new complications in the Higgs sector and in the running of the renormalisation group equations.
1609.06886
Alfredo Valcarce
H. Garcilazo, A. Valcarce, J. Vijande
Doubly heavy baryon spectra guided by lattice QCD
17 pages, 3 figures. To be published in Phys. Rev. D. Two references have been added
Phys. Rev. D94, 074003 (2016)
10.1103/PhysRevD.94.074003
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper provides results for the ground state and excited spectra of three-flavored doubly heavy baryons, $bcn$ and $bcs$. We take advantage of the spin-independent interaction recently obtained to reconcile the lattice SU(3) QCD static potential and the results of nonperturbative lattice QCD for the triply heavy baryon spectra. We show that the spin-dependent potential might be constrained on the basis of nonperturbative lattice QCD results for the spin splittings of three-flavored doubly heavy baryons. Our results may also represent a challenge for future lattice QCD work, because a smaller lattice error could help in distinguishing between different prescriptions for the spin-dependent part of the interaction. Thus, by comparing with the reported baryon spectra obtained with parameters estimated from lattice QCD, one can challenge the precision of lattice calculations. The present work supports a coherent description of singly, doubly and triply heavy baryons with the same Cornell-like interacting potential. The possible experimental measurement of these states at LHCb is an incentive for this study.
[ { "created": "Thu, 22 Sep 2016 09:38:40 GMT", "version": "v1" }, { "created": "Thu, 29 Sep 2016 10:42:52 GMT", "version": "v2" } ]
2016-10-04
[ [ "Garcilazo", "H.", "" ], [ "Valcarce", "A.", "" ], [ "Vijande", "J.", "" ] ]
This paper provides results for the ground state and excited spectra of three-flavored doubly heavy baryons, $bcn$ and $bcs$. We take advantage of the spin-independent interaction recently obtained to reconcile the lattice SU(3) QCD static potential and the results of nonperturbative lattice QCD for the triply heavy baryon spectra. We show that the spin-dependent potential might be constrained on the basis of nonperturbative lattice QCD results for the spin splittings of three-flavored doubly heavy baryons. Our results may also represent a challenge for future lattice QCD work, because a smaller lattice error could help in distinguishing between different prescriptions for the spin-dependent part of the interaction. Thus, by comparing with the reported baryon spectra obtained with parameters estimated from lattice QCD, one can challenge the precision of lattice calculations. The present work supports a coherent description of singly, doubly and triply heavy baryons with the same Cornell-like interacting potential. The possible experimental measurement of these states at LHCb is an incentive for this study.
hep-ph/9703310
Bradley D. Keister
B. D. Keister (Carnegie Mellon U)
Relativity and the Minimum Slope of the Isgur-Wise Function
revised to incorporate additional references
null
null
null
hep-ph
null
Sum rules based upon heavy quark effective theory indicate that the Isgur-Wise function $\xi(w)$ has a minimum slope as w approaches 1, which is zero for light degrees of freedom with zero spin and 1/4 for light spin 1/2. Quark-model studies reveal sources for a minimum slope from a variety of relativistic effects. In this paper the origins of the minimum slope in the sum-rule and quark-model approaches are compared by considering hadrons with arbitrary light spin. In both approaches the minimum slope increases with the light spin, but there appears to be no detailed correspondence between the quark-model and sum-rule approaches.
[ { "created": "Wed, 12 Mar 1997 21:02:49 GMT", "version": "v1" }, { "created": "Tue, 3 Jun 1997 17:36:59 GMT", "version": "v2" } ]
2008-02-03
[ [ "Keister", "B. D.", "", "Carnegie Mellon U" ] ]
Sum rules based upon heavy quark effective theory indicate that the Isgur-Wise function $\xi(w)$ has a minimum slope as w approaches 1, which is zero for light degrees of freedom with zero spin and 1/4 for light spin 1/2. Quark-model studies reveal sources for a minimum slope from a variety of relativistic effects. In this paper the origins of the minimum slope in the sum-rule and quark-model approaches are compared by considering hadrons with arbitrary light spin. In both approaches the minimum slope increases with the light spin, but there appears to be no detailed correspondence between the quark-model and sum-rule approaches.
hep-ph/0510408
Matthias Burkardt
Matthias Burkardt (New Mexico State University)
GPD's and Ssa's
8 pages, invited talk presented at "Workshop on Transverse Polarisation Phenomena in Hard Processes" (Transversity 2005), Villa Olmo (Como), 7-10th September 2005
null
10.1142/9789812773272_0018
null
hep-ph
null
Generalized parton distributions involving transverse polarization are transversely deformed. The deformation of chirally odd GPDs is related to a transversity decomposition of the quark angular momentum. Potential consequences for T-odd single-spin asymmetries (Sivers and Boer-Mulders effects) are discussed.
[ { "created": "Mon, 31 Oct 2005 15:28:55 GMT", "version": "v1" } ]
2017-08-23
[ [ "Burkardt", "Matthias", "", "New Mexico State University" ] ]
Generalized parton distributions involving transverse polarization are transversely deformed. The deformation of chirally odd GPDs is related to a transversity decomposition of the quark angular momentum. Potential consequences for T-odd single-spin asymmetries (Sivers and Boer-Mulders effects) are discussed.
1209.4816
A. D. Polosa
L. Maiani, A. D. Polosa and V. Riquer
Heavier Higgs Particles: Indications from Minimal Supersymmetry
5 pages, 5 figures. Clarifications and new references added
null
10.1016/j.physletb.2012.10.041
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use the most recent data on the Higgs-like resonance h observed at 125 GeV to derive information about the mass of the heavier Higgs particles predicted by Minimal Supersymmetry. We treat as independent parameters the couplings of h to top quark, beauty and massive vector bosons and, in this three dimensional space, we locate the point realizing the best fit to data and compare it to the position of the Standard Model point and to the region of coupling values accommodating heavier Higgs particles in Minimal Supersymmetry. We conclude that mass values 320< M_H< 360 GeV are compatible at 2sigma with the best fit of couplings to present data, larger values being compatible at the 1sigma level. Values of 1< tan(beta)< 6 are compatible with data.
[ { "created": "Fri, 21 Sep 2012 13:28:32 GMT", "version": "v1" }, { "created": "Thu, 18 Oct 2012 15:21:57 GMT", "version": "v2" } ]
2015-06-11
[ [ "Maiani", "L.", "" ], [ "Polosa", "A. D.", "" ], [ "Riquer", "V.", "" ] ]
We use the most recent data on the Higgs-like resonance h observed at 125 GeV to derive information about the mass of the heavier Higgs particles predicted by Minimal Supersymmetry. We treat as independent parameters the couplings of h to top quark, beauty and massive vector bosons and, in this three dimensional space, we locate the point realizing the best fit to data and compare it to the position of the Standard Model point and to the region of coupling values accommodating heavier Higgs particles in Minimal Supersymmetry. We conclude that mass values 320< M_H< 360 GeV are compatible at 2sigma with the best fit of couplings to present data, larger values being compatible at the 1sigma level. Values of 1< tan(beta)< 6 are compatible with data.
hep-ph/0404292
Abhijit Majumder
A. Majumder
Dihadron fragmentation functions and high Pt hadron-hadron correlations
Latex, 4 pages, 4 figures, talk given at Quark Matter 2004, To appear in J. Phys. G
J.Phys.G30:S1305-S1308,2004
10.1088/0954-3899/30/8/114
null
hep-ph nucl-th
null
We propose the formulation of a dihadron fragmentation function in terms of parton matrix elements. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at leading order (LO) in e+ e- annihilation is shown to factorize into a short distance parton cross section and the long distance dihadron fragmentation function. We also derive the DGLAP evolution equation of this function at leading log. The evolution equation for the non-singlet quark fragmentation function is solved numerically with a simple ansatz for the initial condition and results are presented for cases of physical interest.
[ { "created": "Fri, 30 Apr 2004 19:48:21 GMT", "version": "v1" } ]
2014-11-17
[ [ "Majumder", "A.", "" ] ]
We propose the formulation of a dihadron fragmentation function in terms of parton matrix elements. Under the collinear factorization approximation and facilitated by the cut-vertex technique, the two hadron inclusive cross section at leading order (LO) in e+ e- annihilation is shown to factorize into a short distance parton cross section and the long distance dihadron fragmentation function. We also derive the DGLAP evolution equation of this function at leading log. The evolution equation for the non-singlet quark fragmentation function is solved numerically with a simple ansatz for the initial condition and results are presented for cases of physical interest.
2203.07726
Wolfgang Altmannshofer
Wolfgang Altmannshofer, Jure Zupan
Snowmass White Paper: Flavor Model Building
34 pages, 2 figures; contribution to Snowmass 2021; solicited whitepaper for TF08; comments are welcome; v2: references added; v3: more references added; v4: figure 1 corrected, more references added; v5: typos corrected
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this white paper for the Snowmass process, we summarize the role flavor model building plays in the quest for new physics. We review approaches to address the non-generic flavor structure of the Standard Model and discuss how new physics models can be made compatible with the stringent constraints from flavor changing processes that indirectly probe very high scales. We also give an overview of the persistent anomalies in B decays and the anomalous magnetic moment of the muon and some of their most popular new physics explanations.
[ { "created": "Tue, 15 Mar 2022 08:47:33 GMT", "version": "v1" }, { "created": "Mon, 11 Apr 2022 16:29:44 GMT", "version": "v2" }, { "created": "Thu, 2 Jun 2022 00:28:03 GMT", "version": "v3" }, { "created": "Tue, 30 Aug 2022 19:22:12 GMT", "version": "v4" }, { "cr...
2023-03-24
[ [ "Altmannshofer", "Wolfgang", "" ], [ "Zupan", "Jure", "" ] ]
In this white paper for the Snowmass process, we summarize the role flavor model building plays in the quest for new physics. We review approaches to address the non-generic flavor structure of the Standard Model and discuss how new physics models can be made compatible with the stringent constraints from flavor changing processes that indirectly probe very high scales. We also give an overview of the persistent anomalies in B decays and the anomalous magnetic moment of the muon and some of their most popular new physics explanations.
1309.0021
Christopher Potter
Tao Liu and C.T. Potter
Exotic Higgs Decay h to 2a at the International Linear Collider: a Snowmass White Paper
8 pages, 2 figures, Snowmass 2013
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A Higgs factory like the International Linear Collider (ILC) can play a significant role in searching for exotic decays of Higgs bosons. As an illustration, we investigate the ILC sensitivity for the decay topology $h\to a_1 a_1 \to \tau\bar \tau\tau \bar \tau$ in the Next-to-Minimal-Supersymmetric-Standard-Model (NMSSM). Here $h$ can be either Standard-Model-like or non-standard, and $a_{1}$ is the lightest CP-odd Higgs boson. We also compare results to expectations for this channel at the LHC.
[ { "created": "Fri, 30 Aug 2013 20:27:43 GMT", "version": "v1" } ]
2013-09-03
[ [ "Liu", "Tao", "" ], [ "Potter", "C. T.", "" ] ]
A Higgs factory like the International Linear Collider (ILC) can play a significant role in searching for exotic decays of Higgs bosons. As an illustration, we investigate the ILC sensitivity for the decay topology $h\to a_1 a_1 \to \tau\bar \tau\tau \bar \tau$ in the Next-to-Minimal-Supersymmetric-Standard-Model (NMSSM). Here $h$ can be either Standard-Model-like or non-standard, and $a_{1}$ is the lightest CP-odd Higgs boson. We also compare results to expectations for this channel at the LHC.
hep-ph/9910246
Josephine Bolosan
S. Pakvasa
Neutrino Anomalies without Oscillations
14pages, LATEX format, 3 figures
Pramana 54:65-77,2000
10.1007/s12043-000-0007-3
UH-511-941-99
hep-ph hep-ex
null
I review explanations for the three neutrino anomalies (solar, atmospheric and LSND) which go beyond the ``conventional'' neutrino oscillations induced by mass-mixing. Several of these require non-zero neutrino masses as well.
[ { "created": "Wed, 6 Oct 1999 00:55:13 GMT", "version": "v1" }, { "created": "Thu, 7 Oct 1999 20:48:13 GMT", "version": "v2" } ]
2009-10-31
[ [ "Pakvasa", "S.", "" ] ]
I review explanations for the three neutrino anomalies (solar, atmospheric and LSND) which go beyond the ``conventional'' neutrino oscillations induced by mass-mixing. Several of these require non-zero neutrino masses as well.
1411.3462
C. A. Dominguez
C. A. Dominguez
Analytical determination of the QCD quark masses
To appear as a chapter in the book {\it{Fifty Years of Quarks}}, H. Fritzsch and M. Gell-Mann, editors (World Scientific Publishing Company, Singapore). Also, to be published in Int. J. Mod. Phys
null
10.1142/S0217751X14300695
UCT-TP-301/2014
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The current status of determinations of the QCD running quark masses is reviewed. Emphasis is on recent progress on analytical precision determinations based on finite energy QCD sum rules. A critical discussion of the merits of this approach over other alternative QCD sum rules is provided. Systematic uncertainties from both the hadronic and the QCD sector have been recently identified and dealt with successfully, thus leading to values of the quark masses with unprecedented accuracy. Results currently rival in precision with lattice QCD determinations.
[ { "created": "Thu, 13 Nov 2014 08:34:01 GMT", "version": "v1" } ]
2015-06-23
[ [ "Dominguez", "C. A.", "" ] ]
The current status of determinations of the QCD running quark masses is reviewed. Emphasis is on recent progress on analytical precision determinations based on finite energy QCD sum rules. A critical discussion of the merits of this approach over other alternative QCD sum rules is provided. Systematic uncertainties from both the hadronic and the QCD sector have been recently identified and dealt with successfully, thus leading to values of the quark masses with unprecedented accuracy. Results currently rival in precision with lattice QCD determinations.
hep-ph/9912307
Peter Arnold
Peter Arnold
An effective theory for omega << k << gT color dynamics in hot non-Abelian plasmas
19 pages
Phys.Rev.D62:036003,2000
10.1103/PhysRevD.62.036003
null
hep-ph
null
A proper sequence of effective theories, corresponding to larger and larger distance scales, is crucial for analyzing real-time equilibrium physics in hot non-Abelian plasmas. For the study of color dynamics (by which I mean physics involving long wavelength gauge fluctuations), an important stepping stone in the sequence of effective theories is to have a good effective theory for dynamics with wave number k well below the Debye screening mass. I review how such dynamics is associated with inverse time scales omega << k. I then give a compact way to package, in the omega << k limit, Bodeker's description of k << m physics, which was in terms of Vlasov equations with collision terms. Finally, I show how the resulting effective theory can be reformulated as a path integral.
[ { "created": "Fri, 10 Dec 1999 22:30:29 GMT", "version": "v1" } ]
2010-02-16
[ [ "Arnold", "Peter", "" ] ]
A proper sequence of effective theories, corresponding to larger and larger distance scales, is crucial for analyzing real-time equilibrium physics in hot non-Abelian plasmas. For the study of color dynamics (by which I mean physics involving long wavelength gauge fluctuations), an important stepping stone in the sequence of effective theories is to have a good effective theory for dynamics with wave number k well below the Debye screening mass. I review how such dynamics is associated with inverse time scales omega << k. I then give a compact way to package, in the omega << k limit, Bodeker's description of k << m physics, which was in terms of Vlasov equations with collision terms. Finally, I show how the resulting effective theory can be reformulated as a path integral.
hep-ph/0605204
Tetsuo Shindou
S. T. Petcov, T. Shindou
LFV radiative Decays and Leptogenesis in the SUSY seesaw model
4 pages, 2 figures, improvements on the text, talk at the XLIst Rencontres de Moriond, Electroweak Interactions and Unified Theories, La Thuile, Italy, 11-18 March 2006
null
null
null
hep-ph
null
The lepton flavour violating charged lepton decays mu to e + gamma and thermal leptogenesis are analysed in the minimal supersymmetric standard model with see-saw mechanism of neutrino mass generation and soft supersymmetry breaking terms with universal boundary conditions. Hierarchical spectrum of heavy Majorana neutrino masses, M_1 << M_2 << M_3, is considered. In this scenario, the requirement of successful thermal leptogenesis implies a lower bound on M_1. For the natural GUT values of the heaviest right-handed Majorana neutrino mass, M_3 > 5 times 10^{13} GeV, and supersymmetry particle masses in the few times 100 GeV range, the predicted mu to e + gamma decay rate exceeds by few order of magnitude the experimental upper limit. This problem is avoided if the matrix of neutrino Yukawa couplings has a specific structure. The latter leads to a correlation between the baryon asymmetry of the Universe predicted by leptogenesis, BR(mu to e + gamma) and the effective Majorana mass in neutrinoless double beta decay.
[ { "created": "Thu, 18 May 2006 11:33:32 GMT", "version": "v1" }, { "created": "Mon, 29 May 2006 09:17:05 GMT", "version": "v2" } ]
2007-05-23
[ [ "Petcov", "S. T.", "" ], [ "Shindou", "T.", "" ] ]
The lepton flavour violating charged lepton decays mu to e + gamma and thermal leptogenesis are analysed in the minimal supersymmetric standard model with see-saw mechanism of neutrino mass generation and soft supersymmetry breaking terms with universal boundary conditions. Hierarchical spectrum of heavy Majorana neutrino masses, M_1 << M_2 << M_3, is considered. In this scenario, the requirement of successful thermal leptogenesis implies a lower bound on M_1. For the natural GUT values of the heaviest right-handed Majorana neutrino mass, M_3 > 5 times 10^{13} GeV, and supersymmetry particle masses in the few times 100 GeV range, the predicted mu to e + gamma decay rate exceeds by few order of magnitude the experimental upper limit. This problem is avoided if the matrix of neutrino Yukawa couplings has a specific structure. The latter leads to a correlation between the baryon asymmetry of the Universe predicted by leptogenesis, BR(mu to e + gamma) and the effective Majorana mass in neutrinoless double beta decay.
hep-ph/9804346
Anjan Joshipura
Anjan S. Joshipura
R Parity Violation: Constraints and Implications
LaTex, 6 pages, 3 figures. Talk presented at the International workshop on "Physics Beyond Standard Model: From Theory to Experiments", Valencia, Spain (October 13-17,1997), to appear in the Proceedings
null
null
null
hep-ph
null
The constraints on trilinear R parity violating couplings $\lambda'_{ijk}$ following from ({\em i}) the neutrino mass resulting due to the induced vacuum expectation value for the sneutrino and (ii) the charm squark interpretation for the HERA anomalous events are discussed in this talk.}
[ { "created": "Tue, 21 Apr 1998 12:13:54 GMT", "version": "v1" } ]
2007-05-23
[ [ "Joshipura", "Anjan S.", "" ] ]
The constraints on trilinear R parity violating couplings $\lambda'_{ijk}$ following from ({\em i}) the neutrino mass resulting due to the induced vacuum expectation value for the sneutrino and (ii) the charm squark interpretation for the HERA anomalous events are discussed in this talk.}
1103.0037
John R. Hiller
S. S. Chabysheva, J. R. Hiller
A light-front coupled-cluster method for the nonperturbative solution of quantum field theories
11 pages, 4 figures, RevTeX 4.1; expanded description of method and replaced QED with simpler model for illustration
null
10.1016/j.physletb.2012.04.032
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new method for the nonperturbative solution of quantum field theories and illustrate its use in the context of a light-front analog to the Greenberg--Schweber model. The method is based on light-front quantization and uses the exponential-operator technique of the many-body coupled-cluster method. The formulation produces an effective Hamiltonian eigenvalue problem in the valence Fock sector of the system of interest, combined with nonlinear integral equations to be solved for the functions that define the effective Hamiltonian. The method avoids the Fock-space truncations usually used in nonperturbative light-front Hamiltonian methods and, therefore, does not suffer from the spectator dependence, Fock-sector dependence, and uncanceled divergences caused by such truncations.
[ { "created": "Mon, 28 Feb 2011 22:03:21 GMT", "version": "v1" }, { "created": "Mon, 27 Feb 2012 15:46:35 GMT", "version": "v2" } ]
2015-05-27
[ [ "Chabysheva", "S. S.", "" ], [ "Hiller", "J. R.", "" ] ]
We propose a new method for the nonperturbative solution of quantum field theories and illustrate its use in the context of a light-front analog to the Greenberg--Schweber model. The method is based on light-front quantization and uses the exponential-operator technique of the many-body coupled-cluster method. The formulation produces an effective Hamiltonian eigenvalue problem in the valence Fock sector of the system of interest, combined with nonlinear integral equations to be solved for the functions that define the effective Hamiltonian. The method avoids the Fock-space truncations usually used in nonperturbative light-front Hamiltonian methods and, therefore, does not suffer from the spectator dependence, Fock-sector dependence, and uncanceled divergences caused by such truncations.
1410.3869
Enrique Ruiz Arriola
E. Ruiz Arriola, L.L. Salcedo, E. Megias
Quark Hadron Duality at Finite Temperature
46 pages, Presented by ERA at the LIV Cracow School of Theoretical Physics on QCD meets experiment. June 12-20, 2014
null
10.5506/APhysPolB.45.2407
UAB-FT-764, MPP-2014-370
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
At low temperatures we expect that all QCD observables are defined in terms of hadrons. This includes the partition function as well as the Polyakov loop in all representations. We analyze the physics underlying a microscopic derivation of the hadron resonance gas.
[ { "created": "Tue, 14 Oct 2014 21:21:10 GMT", "version": "v1" } ]
2015-06-23
[ [ "Arriola", "E. Ruiz", "" ], [ "Salcedo", "L. L.", "" ], [ "Megias", "E.", "" ] ]
At low temperatures we expect that all QCD observables are defined in terms of hadrons. This includes the partition function as well as the Polyakov loop in all representations. We analyze the physics underlying a microscopic derivation of the hadron resonance gas.
0801.2288
A. D. Polosa
G. 't Hooft, G. Isidori, L. Maiani, A.D. Polosa, V. Riquer
A Theory of Scalar Mesons
10 pages, 2 figures. References added. Presentation improved. Unchanged in substance. To appear in Phys Lett B
Phys.Lett.B662:424-430,2008
10.1016/j.physletb.2008.03.036
null
hep-ph
null
We discuss the effect of the instanton induced, six-fermion effective Lagrangian on the decays of the lightest scalar mesons in the diquark--antidiquark picture. This addition allows for a remarkably good description of light scalar meson decays. The same effective Lagrangian produces a mixing of the lightest scalars with the positive parity q-qbar states. Comparing with previous work where the q-qbar mesons are identified with the nonet at 1200-1700 MeV, we find that the mixing required to fit the mass spectrum is in good agreement with the instanton coupling obtained from light scalar decays. A coherent picture of scalar mesons as a mixture of tetraquark states (dominating in the lightest mesons) and heavy q-qbar states (dominating in the heavier mesons) emerges.
[ { "created": "Tue, 15 Jan 2008 13:12:07 GMT", "version": "v1" }, { "created": "Sun, 23 Mar 2008 18:34:04 GMT", "version": "v2" } ]
2008-12-18
[ [ "Hooft", "G. 't", "" ], [ "Isidori", "G.", "" ], [ "Maiani", "L.", "" ], [ "Polosa", "A. D.", "" ], [ "Riquer", "V.", "" ] ]
We discuss the effect of the instanton induced, six-fermion effective Lagrangian on the decays of the lightest scalar mesons in the diquark--antidiquark picture. This addition allows for a remarkably good description of light scalar meson decays. The same effective Lagrangian produces a mixing of the lightest scalars with the positive parity q-qbar states. Comparing with previous work where the q-qbar mesons are identified with the nonet at 1200-1700 MeV, we find that the mixing required to fit the mass spectrum is in good agreement with the instanton coupling obtained from light scalar decays. A coherent picture of scalar mesons as a mixture of tetraquark states (dominating in the lightest mesons) and heavy q-qbar states (dominating in the heavier mesons) emerges.
1511.04473
Fred Jegerlehner
Fred Jegerlehner
Leading-order hadronic contribution to the electron and muon g-2
10 pages, 21 figures, including updated BESIII results arXiv:1507.08188v3, results slightly go down
null
10.1051/epjconf/201611801016
DESY 15-220, HU-EP-15/53
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I present a new data driven update of the hadronic vacuum polarization effects for the muon and the electron $g-2$. For the leading order contributions I find $a_\mu^{\mathrm{had}(1)}=(686.99\pm 4.21)[687.19\pm 3.48]\times 10^{-10}$ based on $e^+e^-$data [incl. $\tau$ data], $a_\mu^{\mathrm{had}(2)}= (-9.934\pm 0.091) \times 10^{-10}$ (NLO) and $a_\mu^{\mathrm{had}(3)}= (1.226\pm 0.012) \times 10^{-10}$ (NNLO) for the muon, and $a_e^{\mathrm{had}(1)}=(184.64\pm 1.21)\times 10^{-14}$ (LO), $a_e^{\mathrm{had}(2)}=(-22.10\pm 0.14)\times 10^{-14}$ (NLO) and $a_e^{\mathrm{had}(3)}=(2.79\pm 0.02)\times 10^{-14}$ (NNLO) for the electron. A problem with vacuum polarization undressing of cross-sections (time-like region) is addressed. I also add a comment on properly including axial mesons in the hadronic light-by-light scattering contribution. My estimate here reads $a_\mu[a_1,f_1',f_1] \sim ({ 7.51 \pm 2.71}) \times 10^{-11}\,.$ With these updates $a_\mu^{\rm exp}-a_\mu^{\rm the}=(32.73\pm 8.15)\times 10^{-10}$ a 4.0 $\sigma$ deviation, while $a_e^{\rm exp}-a_e^{\rm the}=(-1.10\pm 0.82)\times 10^{-12}$ shows no significant deviation.
[ { "created": "Fri, 13 Nov 2015 22:18:31 GMT", "version": "v1" }, { "created": "Thu, 10 Dec 2015 16:54:47 GMT", "version": "v2" } ]
2016-06-22
[ [ "Jegerlehner", "Fred", "" ] ]
I present a new data driven update of the hadronic vacuum polarization effects for the muon and the electron $g-2$. For the leading order contributions I find $a_\mu^{\mathrm{had}(1)}=(686.99\pm 4.21)[687.19\pm 3.48]\times 10^{-10}$ based on $e^+e^-$data [incl. $\tau$ data], $a_\mu^{\mathrm{had}(2)}= (-9.934\pm 0.091) \times 10^{-10}$ (NLO) and $a_\mu^{\mathrm{had}(3)}= (1.226\pm 0.012) \times 10^{-10}$ (NNLO) for the muon, and $a_e^{\mathrm{had}(1)}=(184.64\pm 1.21)\times 10^{-14}$ (LO), $a_e^{\mathrm{had}(2)}=(-22.10\pm 0.14)\times 10^{-14}$ (NLO) and $a_e^{\mathrm{had}(3)}=(2.79\pm 0.02)\times 10^{-14}$ (NNLO) for the electron. A problem with vacuum polarization undressing of cross-sections (time-like region) is addressed. I also add a comment on properly including axial mesons in the hadronic light-by-light scattering contribution. My estimate here reads $a_\mu[a_1,f_1',f_1] \sim ({ 7.51 \pm 2.71}) \times 10^{-11}\,.$ With these updates $a_\mu^{\rm exp}-a_\mu^{\rm the}=(32.73\pm 8.15)\times 10^{-10}$ a 4.0 $\sigma$ deviation, while $a_e^{\rm exp}-a_e^{\rm the}=(-1.10\pm 0.82)\times 10^{-12}$ shows no significant deviation.
1707.08600
Patrick Komiske
Patrick T. Komiske, Eric M. Metodiev, Benjamin Nachman, Matthew D. Schwartz
Pileup Mitigation with Machine Learning (PUMML)
20 pages, 8 figures, 2 tables. Updated to JHEP version
JHEP 12 (2017) 051
10.1007/JHEP12(2017)051
MIT-CTP 4924
hep-ph hep-ex stat.ML
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Pileup involves the contamination of the energy distribution arising from the primary collision of interest (leading vertex) by radiation from soft collisions (pileup). We develop a new technique for removing this contamination using machine learning and convolutional neural networks. The network takes as input the energy distribution of charged leading vertex particles, charged pileup particles, and all neutral particles and outputs the energy distribution of particles coming from leading vertex alone. The PUMML algorithm performs remarkably well at eliminating pileup distortion on a wide range of simple and complex jet observables. We test the robustness of the algorithm in a number of ways and discuss how the network can be trained directly on data.
[ { "created": "Wed, 26 Jul 2017 18:27:43 GMT", "version": "v1" }, { "created": "Mon, 4 Sep 2017 17:30:20 GMT", "version": "v2" }, { "created": "Mon, 8 Jan 2018 21:14:44 GMT", "version": "v3" } ]
2018-01-10
[ [ "Komiske", "Patrick T.", "" ], [ "Metodiev", "Eric M.", "" ], [ "Nachman", "Benjamin", "" ], [ "Schwartz", "Matthew D.", "" ] ]
Pileup involves the contamination of the energy distribution arising from the primary collision of interest (leading vertex) by radiation from soft collisions (pileup). We develop a new technique for removing this contamination using machine learning and convolutional neural networks. The network takes as input the energy distribution of charged leading vertex particles, charged pileup particles, and all neutral particles and outputs the energy distribution of particles coming from leading vertex alone. The PUMML algorithm performs remarkably well at eliminating pileup distortion on a wide range of simple and complex jet observables. We test the robustness of the algorithm in a number of ways and discuss how the network can be trained directly on data.
1603.07687
Francesco Giacosa
Francesco Giacosa, Viktor Begun, and Wojciech Broniowski
Irrelevance of $f_{0}(500)$ in bulk thermal properties
Talk presented at XI Workshop on Particle Correlations and Femtoscopy, 3-7 November 2015, Warsaw, Poland. 4 pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss why the scalar-isoscalar resonance $f_{0}(500)$ should in practice not be included in thermal models describing the freeze-out of heavy-ion collisions. Its contribution into pion multiplicities is in principle relevant because it is light and it decays only into pions. However, it is cancelled to a very good numerical precision by the non-resonant scalar-isotensor repulsion among pions. Our approach is an application of a well-known theorem relating spectral function to phase shifts. The numerical results are solely based on pion-pion scattering data and thus model independent.
[ { "created": "Thu, 24 Mar 2016 18:03:55 GMT", "version": "v1" } ]
2016-03-25
[ [ "Giacosa", "Francesco", "" ], [ "Begun", "Viktor", "" ], [ "Broniowski", "Wojciech", "" ] ]
We discuss why the scalar-isoscalar resonance $f_{0}(500)$ should in practice not be included in thermal models describing the freeze-out of heavy-ion collisions. Its contribution into pion multiplicities is in principle relevant because it is light and it decays only into pions. However, it is cancelled to a very good numerical precision by the non-resonant scalar-isotensor repulsion among pions. Our approach is an application of a well-known theorem relating spectral function to phase shifts. The numerical results are solely based on pion-pion scattering data and thus model independent.
1811.04853
A. N. Ivanov
A. N. Ivanov, R. H\"ollwieser, N. I. Troitskaya, M. Wellenzohn, Ya. A. Berdnikov
Test of the Standard Model in Neutron Beta Decay with Polarized Electron and Unpolarized Neutron and Proton
20 pages, 4 figures.The functions in Eq.(A.8) are corrected. arXiv admin note: text overlap with arXiv:1805.03880
Phys. Rev. D 99, 053004 (2019)
10.1103/PhysRevD.99.053004
null
hep-ph gr-qc nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the correlation coefficients of the electron-energy and electron-antineutrino angular distribution of the neutron beta decay with polarized electron and unpolarised neutron and proton. The calculation is carried out within the Standard Model (SM) with the contributions, caused by the weak magnetism, proton recoil and radiative corrections of order of 10^{-3}, Wilkinson's corrections of order 10^{-5}$(Wilkinson, Nucl. Phys. A377, 474 (1982) and Ivanov et al., Phys. Rev. C95, 055502 (2017)) and the contributions of interactions beyond the SM. The obtained results can be used for the analysis of experimental data on searches of interactions beyond the SM at the level of 10^{-4} (Abele, Hyperfine Interact. 237, 155 (2016)). The contributions of G-odd correlations are calculated and found at the level of 10^{-5} in agreement with the results obtained by Gardner and Plaster (Phys. Rev. C87, 065504 (2013)) and Ivanov et al. (Phys. Rev. C98, 035503 (2018)).
[ { "created": "Mon, 12 Nov 2018 16:58:46 GMT", "version": "v1" }, { "created": "Wed, 3 Feb 2021 12:20:22 GMT", "version": "v2" } ]
2021-02-04
[ [ "Ivanov", "A. N.", "" ], [ "Höllwieser", "R.", "" ], [ "Troitskaya", "N. I.", "" ], [ "Wellenzohn", "M.", "" ], [ "Berdnikov", "Ya. A.", "" ] ]
We calculate the correlation coefficients of the electron-energy and electron-antineutrino angular distribution of the neutron beta decay with polarized electron and unpolarised neutron and proton. The calculation is carried out within the Standard Model (SM) with the contributions, caused by the weak magnetism, proton recoil and radiative corrections of order of 10^{-3}, Wilkinson's corrections of order 10^{-5}$(Wilkinson, Nucl. Phys. A377, 474 (1982) and Ivanov et al., Phys. Rev. C95, 055502 (2017)) and the contributions of interactions beyond the SM. The obtained results can be used for the analysis of experimental data on searches of interactions beyond the SM at the level of 10^{-4} (Abele, Hyperfine Interact. 237, 155 (2016)). The contributions of G-odd correlations are calculated and found at the level of 10^{-5} in agreement with the results obtained by Gardner and Plaster (Phys. Rev. C87, 065504 (2013)) and Ivanov et al. (Phys. Rev. C98, 035503 (2018)).
1607.06499
Alexei P. Martynenko
A.P. Martynenko and V.V. Sorokin (Samara U.)
Vacuum polarization and quadrupole corrections to the hyperfine splitting of P-states in muonic deuterium
7 pages
J.Phys. B50 (2017) 045001
10.1088/1361-6455/aa5705
SSU-HEP-16/07
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
On the basis of quasipotential approach in quantum electrodynamics we calculate vacuum polarization and quadrupole corrections in first and second orders of perturbation theory in hyperfine structure of P-states in muonic deuterium. All corrections are presented in integral form and evaluated analytically and numerically. The obtained results can be used for the improvement of the transition frequencies between levels 2P and 2S.
[ { "created": "Thu, 21 Jul 2016 21:00:01 GMT", "version": "v1" } ]
2017-11-28
[ [ "Martynenko", "A. P.", "", "Samara U." ], [ "Sorokin", "V. V.", "", "Samara U." ] ]
On the basis of quasipotential approach in quantum electrodynamics we calculate vacuum polarization and quadrupole corrections in first and second orders of perturbation theory in hyperfine structure of P-states in muonic deuterium. All corrections are presented in integral form and evaluated analytically and numerically. The obtained results can be used for the improvement of the transition frequencies between levels 2P and 2S.
2107.11713
Guang-You Qin
Feng-Lei Liu, Wen-Jing Xing, Xiang-Yu Wu, Guang-You Qin, Shanshan Cao, Xin-Nian Wang
QLBT: A linear Boltzmann transport model for heavy quarks in a quark-gluon plasma of quasi-particles
13 pages, 9 figures
null
10.1140/epjc/s10052-022-10308-x
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop a new heavy quark transport model, QLBT, to simulate the dynamical propagation of heavy quarks inside the quark-gluon plasma (QGP) created in relativistic heavy-ion collisions. Our QLBT model is based on the linear Boltzmann transport (LBT) model with the ideal QGP replaced by a collection of quasi-particles to account for the non-perturbative interactions among quarks and gluons of the hot QGP. The thermal masses of quasi-particles are fitted to the equation of state from lattice QCD simulations using the Bayesian statistical analysis method. Combining QLBT with our advanced hybrid fragmentation-coalescence hadronization approach, we calculate the nuclear modification factor $R_\mathrm{AA}$ and the elliptic flow $v_2$ of $D$ mesons at the Relativistic Heavy-Ion Collider and the Large Hadron Collider. By comparing our QLBT calculation to the experimental data on the $D$ meson $R_\mathrm{AA}$ and $v_2$, we extract the heavy quark transport parameter $\hat{q}$ and diffusion coefficient $D_\mathrm{s}$ in the temperature range of $1-4~T_\mathrm{c}$, and compare them with the lattice QCD results and other phenomenological studies.
[ { "created": "Sun, 25 Jul 2021 02:41:32 GMT", "version": "v1" } ]
2022-05-11
[ [ "Liu", "Feng-Lei", "" ], [ "Xing", "Wen-Jing", "" ], [ "Wu", "Xiang-Yu", "" ], [ "Qin", "Guang-You", "" ], [ "Cao", "Shanshan", "" ], [ "Wang", "Xin-Nian", "" ] ]
We develop a new heavy quark transport model, QLBT, to simulate the dynamical propagation of heavy quarks inside the quark-gluon plasma (QGP) created in relativistic heavy-ion collisions. Our QLBT model is based on the linear Boltzmann transport (LBT) model with the ideal QGP replaced by a collection of quasi-particles to account for the non-perturbative interactions among quarks and gluons of the hot QGP. The thermal masses of quasi-particles are fitted to the equation of state from lattice QCD simulations using the Bayesian statistical analysis method. Combining QLBT with our advanced hybrid fragmentation-coalescence hadronization approach, we calculate the nuclear modification factor $R_\mathrm{AA}$ and the elliptic flow $v_2$ of $D$ mesons at the Relativistic Heavy-Ion Collider and the Large Hadron Collider. By comparing our QLBT calculation to the experimental data on the $D$ meson $R_\mathrm{AA}$ and $v_2$, we extract the heavy quark transport parameter $\hat{q}$ and diffusion coefficient $D_\mathrm{s}$ in the temperature range of $1-4~T_\mathrm{c}$, and compare them with the lattice QCD results and other phenomenological studies.
0802.2702
Gian Paolo Vacca
J. Bartels, M. Salvadore and G.P. Vacca
Inclusive 1-jet Production Cross Section at Small x in QCD: Multiple Interactions
42 pages, 22 figures, few references and comments added, to appear on JHEP
JHEP0806:032,2008
10.1088/1126-6708/2008/06/032
DESY-08-016
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study corrections due to two Pomeron exchanges to the inclusive 1-jet production cross section in the Regge limit of perturbative QCD for a finite number of colors. By considering deep inelastic scattering on a weakly bound two-nucleon system, we carefully follow the logic of the AGK cutting rules and show, for the single inclusive cross section, that, due to the reggeization of the gluon, modifications of the AGK cutting rules appear. As our main result, we investigate and calculate the jet production vertex in the presence of a two-Pomeron cut correction. Compared to previous studies, we find a novel structure of the jet vertex which has not been considered before. We discuss a few implications of this new piece.
[ { "created": "Tue, 19 Feb 2008 20:04:52 GMT", "version": "v1" }, { "created": "Wed, 4 Jun 2008 10:27:53 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bartels", "J.", "" ], [ "Salvadore", "M.", "" ], [ "Vacca", "G. P.", "" ] ]
We study corrections due to two Pomeron exchanges to the inclusive 1-jet production cross section in the Regge limit of perturbative QCD for a finite number of colors. By considering deep inelastic scattering on a weakly bound two-nucleon system, we carefully follow the logic of the AGK cutting rules and show, for the single inclusive cross section, that, due to the reggeization of the gluon, modifications of the AGK cutting rules appear. As our main result, we investigate and calculate the jet production vertex in the presence of a two-Pomeron cut correction. Compared to previous studies, we find a novel structure of the jet vertex which has not been considered before. We discuss a few implications of this new piece.
1804.07310
Matthias Steinhauser
Roman N. Lee, Alexander V. Smirnov, Vladimir A. Smirnov, Matthias Steinhauser
Three-loop massive form factors: complete light-fermion and large-$N_c$ corrections for vector, axial-vector, scalar and pseudo-scalar currents
33 pages
null
10.1007/JHEP05(2018)187
TTP18-015
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the three-loop QCD corrections to the massive quark form factors with external vector, axial-vector, scalar and pseudo-scalar currents. All corrections with closed loops of massless fermions are included. The non-fermionic part is computed in the large-$N_c$ limit, where only planar Feynman diagrams contribute.
[ { "created": "Thu, 19 Apr 2018 18:00:07 GMT", "version": "v1" } ]
2018-07-04
[ [ "Lee", "Roman N.", "" ], [ "Smirnov", "Alexander V.", "" ], [ "Smirnov", "Vladimir A.", "" ], [ "Steinhauser", "Matthias", "" ] ]
We compute the three-loop QCD corrections to the massive quark form factors with external vector, axial-vector, scalar and pseudo-scalar currents. All corrections with closed loops of massless fermions are included. The non-fermionic part is computed in the large-$N_c$ limit, where only planar Feynman diagrams contribute.
2111.04010
Sung Mook Lee
Sung Mook Lee, Dhong Yeon Cheong, Sang Chul Hyun, Seong Chan Park, and Min-Seok Seo
Festina-Lente Bound on Higgs Vacuum Structure and Inflation
14 pages, 3 figures, v2: version appeared in JHEP, expanded appendix A
null
null
null
hep-ph astro-ph.CO gr-qc hep-th
http://creativecommons.org/licenses/by/4.0/
The recently suggested Festina-Lente (FL) bound provides a lower bound on the masses of ${\rm U(1)}$ charged particles in terms of the positive vacuum energy. Since the charged particle masses in the Standard Model (SM) are generated by the Higgs mechanism, the FL bound provides a testbed of consistent Higgs potentials in the current dark energy-dominated universe as well as during inflation. We study the implications of the FL bound on the UV behavior of the Higgs potential for a miniscule vacuum energy, as in the current universe. We also present values of the Hubble parameter and the Higgs vacuum expectation value allowed by the FL bound during inflation, which implies that the Higgs cannot stay at the electroweak scale during this epoch.
[ { "created": "Sun, 7 Nov 2021 05:55:01 GMT", "version": "v1" }, { "created": "Wed, 16 Feb 2022 08:56:33 GMT", "version": "v2" } ]
2022-02-17
[ [ "Lee", "Sung Mook", "" ], [ "Cheong", "Dhong Yeon", "" ], [ "Hyun", "Sang Chul", "" ], [ "Park", "Seong Chan", "" ], [ "Seo", "Min-Seok", "" ] ]
The recently suggested Festina-Lente (FL) bound provides a lower bound on the masses of ${\rm U(1)}$ charged particles in terms of the positive vacuum energy. Since the charged particle masses in the Standard Model (SM) are generated by the Higgs mechanism, the FL bound provides a testbed of consistent Higgs potentials in the current dark energy-dominated universe as well as during inflation. We study the implications of the FL bound on the UV behavior of the Higgs potential for a miniscule vacuum energy, as in the current universe. We also present values of the Hubble parameter and the Higgs vacuum expectation value allowed by the FL bound during inflation, which implies that the Higgs cannot stay at the electroweak scale during this epoch.
1008.5100
George Rupp
Susana Coito, George Rupp, and Eef van Beveren
Delicate interplay between the D0-D*0, rho0-J/psi, and omega-J/psi channels in the X(3872) resonance
v1: 5 pages, 5 figures (7 plots), 2 tables, RevTeX4. v2: 6 pages, 6 figures (9 plots), 2 tables, SVJOUR; substantial revisions, in particular the added omega-J/psi channel; more references. v3: further clarifications added to the text; version accepted for publication in Eur. Phys. J. C
Eur.Phys.J.C71:1762,2011
10.1140/epjc/s10052-011-1762-7
null
hep-ph hep-ex math-ph math.MP
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The nature of the X(3872) enhancement is analysed in the framework of the Resonance-Spectrum Expansion, by studying it as a regular $J^{PC}=1^{++}$ charmonium state, though strongly influenced and shifted by open-charm decay channels. The observed but Okubo-Zweig-Iizuka-forbidden $\rho^0 J/\psi$ and $\omega J/\psi$ channels are coupled as well, but effectively smeared out by using complex $\rho^0$ and $\omega$ masses, in order to account for their physical widths, followed by a rigorous algebraic procedure to restore unitarity. A very delicate interplay between the $D^0 D^{*0}$, $\rho^0 J/\psi$, and $\omega J/\psi$ channels is observed. The data clearly suggest that the X(3872) is a very narrow axial-vector $c\bar{c}$ resonance, with a pole at or slightly below the $D^0D^{*0}$ threshold.
[ { "created": "Mon, 30 Aug 2010 15:36:51 GMT", "version": "v1" }, { "created": "Wed, 15 Jun 2011 15:39:34 GMT", "version": "v2" }, { "created": "Tue, 13 Sep 2011 08:43:40 GMT", "version": "v3" } ]
2011-10-11
[ [ "Coito", "Susana", "" ], [ "Rupp", "George", "" ], [ "van Beveren", "Eef", "" ] ]
The nature of the X(3872) enhancement is analysed in the framework of the Resonance-Spectrum Expansion, by studying it as a regular $J^{PC}=1^{++}$ charmonium state, though strongly influenced and shifted by open-charm decay channels. The observed but Okubo-Zweig-Iizuka-forbidden $\rho^0 J/\psi$ and $\omega J/\psi$ channels are coupled as well, but effectively smeared out by using complex $\rho^0$ and $\omega$ masses, in order to account for their physical widths, followed by a rigorous algebraic procedure to restore unitarity. A very delicate interplay between the $D^0 D^{*0}$, $\rho^0 J/\psi$, and $\omega J/\psi$ channels is observed. The data clearly suggest that the X(3872) is a very narrow axial-vector $c\bar{c}$ resonance, with a pole at or slightly below the $D^0D^{*0}$ threshold.
2310.17710
Hyun Min Lee
Hyun Min Lee, Adriana G. Menkara, Myeong-Jung Seong, Jun-Ho Song
Peccei-Quinn Inflation at the Pole and Axion Kinetic Misalignment
28 pages, 3 figures, v2: improved discussion on the evolution of the axion velocity with a changing equation of state of the inflaton. Version to be published in JHEP
null
null
null
hep-ph hep-th
http://creativecommons.org/licenses/by-nc-sa/4.0/
We propose a minimal extension of the Standard Model with the Peccei-Quinn (PQ) scalar field and explain the relic density of the QCD axion through the kinetic misalignment with a relatively small axion decay constant. To this purpose, we consider a slow-roll inflation from the radial component of the PQ field with the PQ conserving potential near the pole of its kinetic term and investigate the post-inflationary dynamics of the PQ field for reheating. The angular mode of the PQ field, identified with the QCD axion, receives a nonzero velocity during inflation due to the PQ violating potential, evolving with an approximately conserved Noether PQ charge. We determine the reheating temperature from the perturbative decays and scattering processes of the inflaton and obtain dark radiation from the axions produced from the inflaton scattering at a testable level in the future Cosmic Microwave Background experiments. We show the correlation between the reheating temperature, the initial velocity of the axion and the axion decay constant, realizing the axion kinetic misalignment for the correct relic density.
[ { "created": "Thu, 26 Oct 2023 18:11:41 GMT", "version": "v1" }, { "created": "Wed, 1 May 2024 13:11:28 GMT", "version": "v2" } ]
2024-05-02
[ [ "Lee", "Hyun Min", "" ], [ "Menkara", "Adriana G.", "" ], [ "Seong", "Myeong-Jung", "" ], [ "Song", "Jun-Ho", "" ] ]
We propose a minimal extension of the Standard Model with the Peccei-Quinn (PQ) scalar field and explain the relic density of the QCD axion through the kinetic misalignment with a relatively small axion decay constant. To this purpose, we consider a slow-roll inflation from the radial component of the PQ field with the PQ conserving potential near the pole of its kinetic term and investigate the post-inflationary dynamics of the PQ field for reheating. The angular mode of the PQ field, identified with the QCD axion, receives a nonzero velocity during inflation due to the PQ violating potential, evolving with an approximately conserved Noether PQ charge. We determine the reheating temperature from the perturbative decays and scattering processes of the inflaton and obtain dark radiation from the axions produced from the inflaton scattering at a testable level in the future Cosmic Microwave Background experiments. We show the correlation between the reheating temperature, the initial velocity of the axion and the axion decay constant, realizing the axion kinetic misalignment for the correct relic density.
hep-ph/9808220
Leonid Burakovsky
L. Burakovsky and T. Goldman
Comment on "Regge Trajectories for All Flavors"
2 pages, LaTeX
Phys.Rev.Lett.82:457,1999
10.1103/PhysRevLett.82.457
LA-UR-98-3390
hep-ph nucl-th
null
We show that Regge trajectories for all flavors suggested recently by Filipponi et al. cannot combine both meson spectroscopy and additivity of intercepts. Other defects of these trajectories are also discussed.
[ { "created": "Tue, 4 Aug 1998 17:51:50 GMT", "version": "v1" } ]
2008-11-26
[ [ "Burakovsky", "L.", "" ], [ "Goldman", "T.", "" ] ]
We show that Regge trajectories for all flavors suggested recently by Filipponi et al. cannot combine both meson spectroscopy and additivity of intercepts. Other defects of these trajectories are also discussed.
hep-ph/9504302
Andre Likhoded
A.V.Berezhnoy, A.K.Likhoded, O.P.Yushchenko
Some Features of the Hadronic $B_c^{(*)}$-meson Production at Large $p_T$
4 pages, REVTEX file, 5 figures (uuencoded compressed tar-file)
Phys.Atom.Nucl. 59 (1996) 709-713; Yad.Fiz. 59N4 (1996) 742-746
null
IHEP 95-59, Protvino
hep-ph
null
Calculations of the hadronic $B^{(*)}_c$-mesons production performed in the framework of the perturbative QCD taking into account $O(\alpha_s^4)$ Feynmann diagrams are presented. A comparison of the exact calculations with those based on the fragmentation model of $\bar b\rightarrow B^{(*)}_c+X$ shows the large discrepancy between them. The exact calculations of the $B^{(*)}_c$-mesons production cross-sections as the function of $p_T$ at the energy of the FNAL Tevatron ($\sqrt{s}=1.8$ TeV) are given. The predicted ratio of the vector to the pseudoscalar state cross-sections is about $R\sim 3$ instead of $R\sim 1.4$ for the fragmentation model.
[ { "created": "Fri, 14 Apr 1995 16:24:56 GMT", "version": "v1" }, { "created": "Fri, 6 Oct 1995 13:31:25 GMT", "version": "v2" } ]
2016-09-01
[ [ "Berezhnoy", "A. V.", "" ], [ "Likhoded", "A. K.", "" ], [ "Yushchenko", "O. P.", "" ] ]
Calculations of the hadronic $B^{(*)}_c$-mesons production performed in the framework of the perturbative QCD taking into account $O(\alpha_s^4)$ Feynmann diagrams are presented. A comparison of the exact calculations with those based on the fragmentation model of $\bar b\rightarrow B^{(*)}_c+X$ shows the large discrepancy between them. The exact calculations of the $B^{(*)}_c$-mesons production cross-sections as the function of $p_T$ at the energy of the FNAL Tevatron ($\sqrt{s}=1.8$ TeV) are given. The predicted ratio of the vector to the pseudoscalar state cross-sections is about $R\sim 3$ instead of $R\sim 1.4$ for the fragmentation model.
hep-ph/0006077
Melles
Michael Melles
Mass gap effects and higher order electroweak Sudakov logarithms
10 pages, 3 figures, LaTeX2e, uses epsfig
Phys.Lett. B495 (2000) 81-86
10.1016/S0370-2693(00)01234-X
PSI-PR-00-10
hep-ph
null
The infrared structure of spontaneously broken gauge theories is phenomenologically very important and theoretically a challenging problem. Various attempts have been made to calculate the higher order behavior of large double-logarithmic (DL) corrections originating from the exchange of electroweak gauge bosons resulting in contradictory claims. We present results from two loop electroweak corrections for the process $g \longrightarrow f_{\rm R} {\bar f}_{\rm L}$ to DL accuracy. This process is ideally suited as a theoretical model reaction to study the effect of the mass gap of the neutral electroweak gauge bosons at the two loop level. Contrary to recent claims in the literature, we find that the calculation performed with the physical Standard Model fields is in perfect agreement with the results from the infrared evolution equation method. In particular, we can confirm the exponentiation of the electroweak Sudakov logarithms through two loops.
[ { "created": "Thu, 8 Jun 2000 15:25:44 GMT", "version": "v1" } ]
2009-10-31
[ [ "Melles", "Michael", "" ] ]
The infrared structure of spontaneously broken gauge theories is phenomenologically very important and theoretically a challenging problem. Various attempts have been made to calculate the higher order behavior of large double-logarithmic (DL) corrections originating from the exchange of electroweak gauge bosons resulting in contradictory claims. We present results from two loop electroweak corrections for the process $g \longrightarrow f_{\rm R} {\bar f}_{\rm L}$ to DL accuracy. This process is ideally suited as a theoretical model reaction to study the effect of the mass gap of the neutral electroweak gauge bosons at the two loop level. Contrary to recent claims in the literature, we find that the calculation performed with the physical Standard Model fields is in perfect agreement with the results from the infrared evolution equation method. In particular, we can confirm the exponentiation of the electroweak Sudakov logarithms through two loops.
1206.5757
Krzysztof Marek Kutak
Krzysztof Kutak
Resummation in nonlinear equation for high energy factorizable gluon density and its extension to include coherence
14 pages, appendix added, accepted for publication in JHEP
JHEP 12 (2012) 033
10.1007/JHEP12(2012)033
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by forthcoming p-Pb experiments at Large Hadron Collider which require both knowledge of gluon densities accounting for saturation and for processes at a wide range of $p_t$ we study basic momentum space evolution equations of high energy QCD factorization. Solutions of those equations might be used to form a set of gluon densities to calculate observables in generalized high energy factorization. Moreover in order to provide a framework for predictions for exclusive final states in p-Pb scattering with high $p_t$ we rewrite the equation for the high energy factorizable gluon density in a resummed form, similarly to what has been done in \cite{Kutak:2011fu} for the BK equation. The resummed equation is then extended to account for colour coherence. This introduces an external scale to the evolution of the gluon density, and therefore makes it applicable in studies of final states.
[ { "created": "Mon, 25 Jun 2012 18:24:24 GMT", "version": "v1" }, { "created": "Fri, 16 Nov 2012 23:14:21 GMT", "version": "v2" } ]
2012-12-18
[ [ "Kutak", "Krzysztof", "" ] ]
Motivated by forthcoming p-Pb experiments at Large Hadron Collider which require both knowledge of gluon densities accounting for saturation and for processes at a wide range of $p_t$ we study basic momentum space evolution equations of high energy QCD factorization. Solutions of those equations might be used to form a set of gluon densities to calculate observables in generalized high energy factorization. Moreover in order to provide a framework for predictions for exclusive final states in p-Pb scattering with high $p_t$ we rewrite the equation for the high energy factorizable gluon density in a resummed form, similarly to what has been done in \cite{Kutak:2011fu} for the BK equation. The resummed equation is then extended to account for colour coherence. This introduces an external scale to the evolution of the gluon density, and therefore makes it applicable in studies of final states.
hep-ph/0602004
Toru Kojo
Toru Kojo, Arata Hayashigaki, Daisuke Jido
Pentaquark state in pole-dominated QCD sum rules
8 pages, 7 figures
Phys.Rev. C74 (2006) 045206
10.1103/PhysRevC.74.045206
YITP-06-05
hep-ph hep-ex hep-lat nucl-ex nucl-th
null
We propose a new approach in QCD sum rules applied for exotic hadrons with a number of quarks, exemplifying the pentaquark Theta^{+} (I=0,J=1/2) in the Borel sum rule. Our approach enables reliable extraction of the pentaquark properties from the sum rule with good stability in a remarkably wide Borel window. The appearance of its valid window originates from a favorable setup of the correlation functions with the aid of it chirality of the interpolating fields on the analogy of the Weinberg sum rule for the vector currents. Our setup leads to large suppression of the continuum contributions which have spoiled the Borel stability in the previous analyses, and consequently enhances importance of the higher-dimensional contributions of the OPE, which are indispensable for investigating the pentaquark properties. Implementing the OPE analysis up to dimension 15, we find that the sum rules for the chiral-even and odd parts independently give the Theta^{+} mass of 1.68 pm 0.22 GeV with uncertainties of the condensate values. Our sum rule indeed gives rather flat Borel curves almost independent of the continuum thresholds both for the mass and pole residue. Finally, we also discuss possible isolation of the observed states from the KN scattering state on view of chiral symmetry.
[ { "created": "Wed, 1 Feb 2006 15:15:08 GMT", "version": "v1" }, { "created": "Fri, 18 Aug 2006 14:24:26 GMT", "version": "v2" } ]
2009-11-11
[ [ "Kojo", "Toru", "" ], [ "Hayashigaki", "Arata", "" ], [ "Jido", "Daisuke", "" ] ]
We propose a new approach in QCD sum rules applied for exotic hadrons with a number of quarks, exemplifying the pentaquark Theta^{+} (I=0,J=1/2) in the Borel sum rule. Our approach enables reliable extraction of the pentaquark properties from the sum rule with good stability in a remarkably wide Borel window. The appearance of its valid window originates from a favorable setup of the correlation functions with the aid of it chirality of the interpolating fields on the analogy of the Weinberg sum rule for the vector currents. Our setup leads to large suppression of the continuum contributions which have spoiled the Borel stability in the previous analyses, and consequently enhances importance of the higher-dimensional contributions of the OPE, which are indispensable for investigating the pentaquark properties. Implementing the OPE analysis up to dimension 15, we find that the sum rules for the chiral-even and odd parts independently give the Theta^{+} mass of 1.68 pm 0.22 GeV with uncertainties of the condensate values. Our sum rule indeed gives rather flat Borel curves almost independent of the continuum thresholds both for the mass and pole residue. Finally, we also discuss possible isolation of the observed states from the KN scattering state on view of chiral symmetry.
2011.01939
Filippo Sala
Yohei Ema, Filippo Sala, Ryosuke Sato
Neutrino experiments probe hadrophilic light dark matter
22 pages, 5 figures, submission to SciPost
SciPost Phys. 10, 072 (2021)
10.21468/SciPostPhys.10.3.072
null
hep-ph astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use Super-K data to place new strong limits on interactions of sub-GeV Dark Matter (DM) with nuclei, that rely on the DM flux inevitably induced by cosmic-ray upscatterings. We derive analogous sensitivities at Hyper-K and DUNE and compare them with others, e.g. at JUNO. Using simplified models, we find that our proposal tests genuinely new parameter space, allowed both by theoretical consistency and by other direct detection experiments, cosmology, meson decays and our recast of monojet. Our results thus motivate and shape a new physics case for any large volume detector sensitive to nuclear recoils.
[ { "created": "Tue, 3 Nov 2020 19:00:01 GMT", "version": "v1" }, { "created": "Wed, 3 Mar 2021 23:19:48 GMT", "version": "v2" } ]
2021-03-24
[ [ "Ema", "Yohei", "" ], [ "Sala", "Filippo", "" ], [ "Sato", "Ryosuke", "" ] ]
We use Super-K data to place new strong limits on interactions of sub-GeV Dark Matter (DM) with nuclei, that rely on the DM flux inevitably induced by cosmic-ray upscatterings. We derive analogous sensitivities at Hyper-K and DUNE and compare them with others, e.g. at JUNO. Using simplified models, we find that our proposal tests genuinely new parameter space, allowed both by theoretical consistency and by other direct detection experiments, cosmology, meson decays and our recast of monojet. Our results thus motivate and shape a new physics case for any large volume detector sensitive to nuclear recoils.
2005.03594
Felix Kling
Felix Kling
Probing Light Gauge Bosons in Tau Neutrino Experiments
10 pages, 2 figures, updated version as published in PRD
Phys. Rev. D 102, 015007 (2020)
10.1103/PhysRevD.102.015007
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The tau neutrino is probably the least studied particle in the SM, with only a handful of interaction events being identified so far. This can in part be attributed to their small production rate in the SM, which occurs mainly through D_s meson decay. However, this also makes the tau neutrino flux measurement an interesting laboratory for additional new physics production modes. In this study, we investigate the possibility of tau neutrino production in the decay of light vector bosons. We consider four scenarios of anomaly-free U(1) gauge groups corresponding to the B-L, B-L_mu-2L_tau, B-L_e-2L_tau and B-3L_tau numbers, analyze current constraints on their parameter spaces and explore the sensitivity of DONuT and as well as the future emulsion detector experiments FASERnu, SND@LHC an SND@SHiP. We find that these experiments provide the leading direct constraints in parts of the parameter space, especially when the vector boson's mass is close to the mass of the omega meson.
[ { "created": "Thu, 7 May 2020 16:24:45 GMT", "version": "v1" }, { "created": "Wed, 22 Jul 2020 20:24:43 GMT", "version": "v2" } ]
2020-07-24
[ [ "Kling", "Felix", "" ] ]
The tau neutrino is probably the least studied particle in the SM, with only a handful of interaction events being identified so far. This can in part be attributed to their small production rate in the SM, which occurs mainly through D_s meson decay. However, this also makes the tau neutrino flux measurement an interesting laboratory for additional new physics production modes. In this study, we investigate the possibility of tau neutrino production in the decay of light vector bosons. We consider four scenarios of anomaly-free U(1) gauge groups corresponding to the B-L, B-L_mu-2L_tau, B-L_e-2L_tau and B-3L_tau numbers, analyze current constraints on their parameter spaces and explore the sensitivity of DONuT and as well as the future emulsion detector experiments FASERnu, SND@LHC an SND@SHiP. We find that these experiments provide the leading direct constraints in parts of the parameter space, especially when the vector boson's mass is close to the mass of the omega meson.
1904.11824
Sheng-Tao Li
Sheng-Tao Li, Gang L\"u
Direct $CP$ violation for $\bar{B}_s^0 \to \phi {\pi^+}{\pi^-}$ in Perturbative QCD
null
Phys. Rev. D 99, 116009 (2019)
10.1103/PhysRevD.99.116009
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In perturbative QCD approach, we study the direct $CP$ violation in the decay of $\bar{B}_s^0\to\rho(\omega )\phi\to {\pi^+}{\pi^-}\phi$ via isospin symmetry breaking. An interesting mechanism involving the charge symmetry violating between $\rho$ and $\omega$ is applied to enlarge the $CP$ violating asymmetry. We find that the $CP$ violation can be enhanced by the $\rho-\omega$ mixing mechanism when the invariant masses of the $\pi^+\pi^-$ pairs are in the vicinity of the $\omega$ resonance. For the decay process of $\bar{B}^0_{s}\to\rho(\omega )\phi\to{\pi^+}{\pi^-}\phi$, the maximum $CP$ violation can reach $5.98\%$. The possibility of detecting the $CP$ violation is also presented.
[ { "created": "Fri, 26 Apr 2019 13:05:14 GMT", "version": "v1" } ]
2019-06-19
[ [ "Li", "Sheng-Tao", "" ], [ "Lü", "Gang", "" ] ]
In perturbative QCD approach, we study the direct $CP$ violation in the decay of $\bar{B}_s^0\to\rho(\omega )\phi\to {\pi^+}{\pi^-}\phi$ via isospin symmetry breaking. An interesting mechanism involving the charge symmetry violating between $\rho$ and $\omega$ is applied to enlarge the $CP$ violating asymmetry. We find that the $CP$ violation can be enhanced by the $\rho-\omega$ mixing mechanism when the invariant masses of the $\pi^+\pi^-$ pairs are in the vicinity of the $\omega$ resonance. For the decay process of $\bar{B}^0_{s}\to\rho(\omega )\phi\to{\pi^+}{\pi^-}\phi$, the maximum $CP$ violation can reach $5.98\%$. The possibility of detecting the $CP$ violation is also presented.
1107.2933
Luca Vecchi
Luca Vecchi
Color & Weak triplet scalars, the dimuon asymmetry in $B_s$ decay, the top forward-backward asymmetry, and the CDF dijet excess
references added, published version
null
10.1007/JHEP10(2011)003
LA-UR-11-10996
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The new physics required to explain the anomalies recently reported by the D0 and CDF collaborations, namely the top forward-backward asymmetry (FBA), the like-sign dimuon charge asymmetry in semileptonic b decay, and the CDF dijet excess, has to feature an amount of flavor symmetry in order to satisfy the severe constrains arising from flavor violation. In this paper we show that, once baryon number conservation is imposed, color & weak triplet scalars with hypercharge $Y=1/3$ can feature the required flavor structure as a consequence of standard model gauge invariance. The color & weak triplet model can simultaneously explain the top FBA and the dimuon charge asymmetry or the dimuon charge asymmetry and the CDF dijet excess. However, the CDF dijet excess appears to be incompatible with the top FBA in the minimal framework. Our model for the dimuon asymmetry predicts the observed pattern $h_d\ll h_s$ in the region of parameter space required to explain the top FBA, whereas our model for the CDF dijet anomaly is characterized by the absence of beyond the SM b-quark jets in the excess region. Compatibility of the color & weak triplet with the electroweak constraints is also discussed. We show that a Higgs boson mass exceeding the LEP bound is typically favored in this scenario, and that both Higgs production and decay can be significantly altered by the triplet. The most promising collider signature is found if the splitting among the components of the triplet is of weak scale magnitude.
[ { "created": "Thu, 14 Jul 2011 20:00:46 GMT", "version": "v1" }, { "created": "Thu, 13 Oct 2011 12:49:05 GMT", "version": "v2" } ]
2015-05-28
[ [ "Vecchi", "Luca", "" ] ]
The new physics required to explain the anomalies recently reported by the D0 and CDF collaborations, namely the top forward-backward asymmetry (FBA), the like-sign dimuon charge asymmetry in semileptonic b decay, and the CDF dijet excess, has to feature an amount of flavor symmetry in order to satisfy the severe constrains arising from flavor violation. In this paper we show that, once baryon number conservation is imposed, color & weak triplet scalars with hypercharge $Y=1/3$ can feature the required flavor structure as a consequence of standard model gauge invariance. The color & weak triplet model can simultaneously explain the top FBA and the dimuon charge asymmetry or the dimuon charge asymmetry and the CDF dijet excess. However, the CDF dijet excess appears to be incompatible with the top FBA in the minimal framework. Our model for the dimuon asymmetry predicts the observed pattern $h_d\ll h_s$ in the region of parameter space required to explain the top FBA, whereas our model for the CDF dijet anomaly is characterized by the absence of beyond the SM b-quark jets in the excess region. Compatibility of the color & weak triplet with the electroweak constraints is also discussed. We show that a Higgs boson mass exceeding the LEP bound is typically favored in this scenario, and that both Higgs production and decay can be significantly altered by the triplet. The most promising collider signature is found if the splitting among the components of the triplet is of weak scale magnitude.
hep-ph/9311368
Tomo Munehisa
J.Fujimoto, Y.Shimizu and T.Munehisa
Monte Carlo Approach to Radiative Corrections in Bhabha Scattering
12 pages, LaTeX, 4 figures available on request KEK-CP-009,KEK Preprint 93-149
Prog.Theor.Phys. 91 (1994) 333-340
10.1143/ptp/91.2.333
null
hep-ph
null
A new Monte Carlo model is proposed for radiative corrections to Bhabha scattering by extending QEDPS developed for multi-photon emission in muon pair production in $e^+e^-$ annihilation. This is the QED version of the model known as parton shower in QCD. The main difference between muon pair production and Bhabha scattering is that the latter cross section shows the singularity of $1/t^2$. A shower algorithm is constructed on the radiator formalism modified in a suitable form for this singularity. Some results of the model are presented and compared with $O(\alpha)$ corrections.
[ { "created": "Mon, 29 Nov 1993 03:11:30 GMT", "version": "v1" } ]
2017-02-01
[ [ "Fujimoto", "J.", "" ], [ "Shimizu", "Y.", "" ], [ "Munehisa", "T.", "" ] ]
A new Monte Carlo model is proposed for radiative corrections to Bhabha scattering by extending QEDPS developed for multi-photon emission in muon pair production in $e^+e^-$ annihilation. This is the QED version of the model known as parton shower in QCD. The main difference between muon pair production and Bhabha scattering is that the latter cross section shows the singularity of $1/t^2$. A shower algorithm is constructed on the radiator formalism modified in a suitable form for this singularity. Some results of the model are presented and compared with $O(\alpha)$ corrections.
hep-ph/9811218
Yuri A. Golubkov
Yu. A. Golubkov
The Distribution of Constituent Charm Quarks in the Hadron
23 pages, 4 PostScript figures, Latex2e. In revised version in comparison with the original one all (?) mistypings have been corrected, one more thank has been added and the comparison of the pion and the proton J/psi production is described in more detail
Phys.Atom.Nucl. 63 (2000) 606-616; Yad.Fiz. 63 (2000) 672-682
10.1134/1.855675
DESY 98-174, November 1998
hep-ph
null
Using a statistical approach in the framework of non-covariant perturbation theory the distributions for light and charmed quarks in the hadron have been derived, taking into account the mass of the charmed quark. The parameters of the model have been extracted from the comparison with NA3 data on hadroproduction of J/psi particles. A reanalysis of the EMC data on charm production in muon-nucleon scattering has been performed. It has been found in comparison with the conventional source of charmed quarks from photon-gluon fusion, that the EMC data indicate the presence of an additional contribution from deep-inelastic scattering on charmed quarks at large x. The resulting admixture of the Fock states, containing charmed quarks in the decomposition of the proton wave function is of the order of 1%. The approach presented for the excitation of the Fock states with charmed quarks can also be applied to states with beauty quarks as well as to the hadronic component of the virtual photon (resolved photon component).
[ { "created": "Mon, 2 Nov 1998 16:39:29 GMT", "version": "v1" }, { "created": "Wed, 11 Nov 1998 16:51:41 GMT", "version": "v2" }, { "created": "Fri, 9 Apr 1999 14:36:42 GMT", "version": "v3" }, { "created": "Sun, 29 Apr 2001 18:22:33 GMT", "version": "v4" } ]
2009-10-31
[ [ "Golubkov", "Yu. A.", "" ] ]
Using a statistical approach in the framework of non-covariant perturbation theory the distributions for light and charmed quarks in the hadron have been derived, taking into account the mass of the charmed quark. The parameters of the model have been extracted from the comparison with NA3 data on hadroproduction of J/psi particles. A reanalysis of the EMC data on charm production in muon-nucleon scattering has been performed. It has been found in comparison with the conventional source of charmed quarks from photon-gluon fusion, that the EMC data indicate the presence of an additional contribution from deep-inelastic scattering on charmed quarks at large x. The resulting admixture of the Fock states, containing charmed quarks in the decomposition of the proton wave function is of the order of 1%. The approach presented for the excitation of the Fock states with charmed quarks can also be applied to states with beauty quarks as well as to the hadronic component of the virtual photon (resolved photon component).
hep-ph/9707533
Vadim Troitsky
A.F. Krutov (Samara Univ.) and V.E. Troitsky (NPI, Moscow Univ.)
Instant-Form Approach to Two-Body Systems
9 pages, latex, no figures Talk presented by V.T. at the Workshop on Relativisic Approaches to Few-Body Systems, Groningen, July 21, 1997
null
null
null
hep-ph
null
We present a relativistic treatment of the problem of soft electromagnetic structure by the modified instant form of relativistic Hamiltonian dynamics. Our approach uses relativistic parametrization and so picks out the relativistic invariant quantities on each stage of the calculation. The electromagnetic current matrix element satisfies the current conservation law automatically. We use relativistic modified impulse approximation. It is constructed in relativistic invariant way. For composite systems (including the spin 1 case) the approach guarantees the uniqueness of the solution and it does not use such concepts as "good" and "bad" current components. The approach describes correctly the spin Wigner rotation and so gives the correct (QCD) asymptotic.
[ { "created": "Thu, 31 Jul 1997 13:24:07 GMT", "version": "v1" } ]
2007-05-23
[ [ "Krutov", "A. F.", "", "Samara Univ." ], [ "Troitsky", "V. E.", "", "NPI, Moscow Univ." ] ]
We present a relativistic treatment of the problem of soft electromagnetic structure by the modified instant form of relativistic Hamiltonian dynamics. Our approach uses relativistic parametrization and so picks out the relativistic invariant quantities on each stage of the calculation. The electromagnetic current matrix element satisfies the current conservation law automatically. We use relativistic modified impulse approximation. It is constructed in relativistic invariant way. For composite systems (including the spin 1 case) the approach guarantees the uniqueness of the solution and it does not use such concepts as "good" and "bad" current components. The approach describes correctly the spin Wigner rotation and so gives the correct (QCD) asymptotic.
1012.1291
Marco Ruggieri
Raoul Gatto and Marco Ruggieri
Deconfinement and Chiral Symmetry Restoration in a Strong Magnetic Background
12 pages, 6 figures, RevTeX 4-1 style. Some reference added. Some typos corrected. To appear on Physical Review D
Phys.Rev.D83:034016,2011
10.1103/PhysRevD.83.034016
YITP-10-96
hep-ph astro-ph.HE hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform a model study of deconfinement and chiral symmetry restoration in a strong magnetic background. We use a Nambu-Jona Lasinio model with the Polyakov loop, taking into account a possible dependence of the coupling on the Polyakov loop expectation value, as suggested by the recent literature. Our main result is that, within this model, the deconfinement and chiral crossovers of QCD in strong magnetic field are entangled even at the largest value of $eB$ considered here, namely $eB=30 m_\pi^2$ (that is, $B \approx 6\times 10^{15}$ Tesla). The amount of split that we measure is, at this value of $eB$, of the order of 2%. We also study briefly the role of the 8-quark term on the entanglement of the two crossovers. We then compare the phase diagram of this model with previous results, as well as with available Lattice data.
[ { "created": "Mon, 6 Dec 2010 19:28:28 GMT", "version": "v1" }, { "created": "Fri, 28 Jan 2011 04:54:50 GMT", "version": "v2" } ]
2015-03-17
[ [ "Gatto", "Raoul", "" ], [ "Ruggieri", "Marco", "" ] ]
We perform a model study of deconfinement and chiral symmetry restoration in a strong magnetic background. We use a Nambu-Jona Lasinio model with the Polyakov loop, taking into account a possible dependence of the coupling on the Polyakov loop expectation value, as suggested by the recent literature. Our main result is that, within this model, the deconfinement and chiral crossovers of QCD in strong magnetic field are entangled even at the largest value of $eB$ considered here, namely $eB=30 m_\pi^2$ (that is, $B \approx 6\times 10^{15}$ Tesla). The amount of split that we measure is, at this value of $eB$, of the order of 2%. We also study briefly the role of the 8-quark term on the entanglement of the two crossovers. We then compare the phase diagram of this model with previous results, as well as with available Lattice data.
1304.2883
Vladimir Zoller
V.A. Novikov and V.R. Zoller
Recovering partial conservation of axial current in diffractive neutrino scattering
7 pages
null
10.1134/S0021364013100081
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A model of diffractive neutrino scattering is formulated in terms of the chiral hadronic current which is conserved in the limit of vanishing pion mass. This current has the correct singularity structure and, naturally, does not lead to contradictions with a partial conservation of the axial current (PCAC). In that respect we differ from earlier work in the literature, where a breakdown of PCAC had been reported. We show that such a breakdown of PCAC is an artifact of the hadronic current non-conservation in the model developed there.
[ { "created": "Wed, 10 Apr 2013 09:18:21 GMT", "version": "v1" }, { "created": "Sun, 14 Apr 2013 15:48:40 GMT", "version": "v2" } ]
2015-06-15
[ [ "Novikov", "V. A.", "" ], [ "Zoller", "V. R.", "" ] ]
A model of diffractive neutrino scattering is formulated in terms of the chiral hadronic current which is conserved in the limit of vanishing pion mass. This current has the correct singularity structure and, naturally, does not lead to contradictions with a partial conservation of the axial current (PCAC). In that respect we differ from earlier work in the literature, where a breakdown of PCAC had been reported. We show that such a breakdown of PCAC is an artifact of the hadronic current non-conservation in the model developed there.
1512.02060
Rainer Schicker M
R. Schicker (Phys. Inst., Heidelberg)
Bound-free pair production in heavy-ion collisions at high energies
Proceedings Conference PHOTON 2015, Budker Institute, Novosibirsk, 15-19 June, 2015, 6 pages, 4 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The electromagnetic process of bound-free electron pair production in heavy-ion collisions at high energies is reviewed. The importance of this process for producing secondary beams is outlined. Single free electron pair production is presented, and the bound-free pair production process is introduced. Double pair production is discussed, and an estimate of the bound-free pair constrained photon-photon luminosity is given.
[ { "created": "Mon, 2 Nov 2015 23:21:46 GMT", "version": "v1" } ]
2015-12-08
[ [ "Schicker", "R.", "", "Phys. Inst., Heidelberg" ] ]
The electromagnetic process of bound-free electron pair production in heavy-ion collisions at high energies is reviewed. The importance of this process for producing secondary beams is outlined. Single free electron pair production is presented, and the bound-free pair production process is introduced. Double pair production is discussed, and an estimate of the bound-free pair constrained photon-photon luminosity is given.
2102.11709
A. A. Natale
A. Doff and A. A. Natale
Limit on Higgs boson trilinear self-coupling in coupled technicolor models
6 pages, 7 figures, 1 table, version to be published
null
10.1209/0295-5075/ac187a
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The trilinear self-coupling of the Higgs boson, in a theory in which this boson is composite, is compared to the experimental bound of this quantity obtained by the CMS experiment. In the case of a model where technicolor (TC) is coupled to QCD, we find that the experimental result already constrain the dynamics of the theory, which is represented by an expression of the technifermion self-energy ($\Sigma_{tc}$) typical of technicolor coupled models, and function of the dynamically generated technifermion mass and two other parameters that describe the technifermion dynamical mass momentum dependence. The limits imposed on this dynamics allow us to make a simple determination of pseudo-Goldstone boson masses that appear in these theories, indicating that these bosons may be expected to be quite massive.
[ { "created": "Tue, 23 Feb 2021 14:26:19 GMT", "version": "v1" }, { "created": "Wed, 24 Feb 2021 13:11:11 GMT", "version": "v2" }, { "created": "Tue, 8 Mar 2022 19:13:01 GMT", "version": "v3" } ]
2022-03-23
[ [ "Doff", "A.", "" ], [ "Natale", "A. A.", "" ] ]
The trilinear self-coupling of the Higgs boson, in a theory in which this boson is composite, is compared to the experimental bound of this quantity obtained by the CMS experiment. In the case of a model where technicolor (TC) is coupled to QCD, we find that the experimental result already constrain the dynamics of the theory, which is represented by an expression of the technifermion self-energy ($\Sigma_{tc}$) typical of technicolor coupled models, and function of the dynamically generated technifermion mass and two other parameters that describe the technifermion dynamical mass momentum dependence. The limits imposed on this dynamics allow us to make a simple determination of pseudo-Goldstone boson masses that appear in these theories, indicating that these bosons may be expected to be quite massive.
hep-ph/0204360
Steve King
S. F. King
Constructing the large mixing angle MNS matrix in see-saw models with right-handed neutrino dominance
Version published in JHEP09(2002)011
JHEP 0209 (2002) 011
10.1088/1126-6708/2002/09/011
null
hep-ph hep-ex nucl-ex
null
Recent SNO results strongly favour the large mixing angle (LMA) MSW solar solution. We argue that there are only two technically natural low energy neutrino mass matrix structures consistent with the LMA MSW solution, corresponding to either a hierarchy or an inverted hierarchy with pseudo-Dirac neutrinos. We first present a model-independent analysis in which we diagonalise each of these two mass matrix structures to leading order in $\theta_{13}$ and extract the neutrino masses, mixing angles and phases. In this analysis we express the MNS matrix to leading order in the small angle $\theta_{13}$ including the neutrino {\em and} charged lepton mixing angles and phases, the latter playing a crucial r\^{o}le for allowing the inverted hierarchy case to be consistent with the LMA MSW solution. We then consider the see-saw mechanism with right-handed neutrino dominance and show how the successful neutrino mass matrix structures may be constructed with no tuning and with small radiative corrections, leading to a full, partial or inverted neutrino mass hierarchy. In each case we derive approximate analytic relations between the input see-saw parameters and the resulting neutrino masses, mixing angles and phases, which will provide a useful guide for unified model building. For the hierarchical cases the LMA MSW solution gives a soft lower bound $|U_{e3}|\simgt 0.1$, just below the current CHOOZ limit. Both hierarchical and inverted hierarchical cases predict small $\beta \beta_{0\nu}$ with $|m_{ee}|\sim 0.01$ eV within the sensitivity of future proposals such as GENIUS. Successful leptogenesis is possible if the dominant right-handed neutrino is the heaviest one, but the leptogenesis phase is unrelated to the MNS phases.
[ { "created": "Tue, 30 Apr 2002 17:17:15 GMT", "version": "v1" }, { "created": "Sat, 4 May 2002 12:57:33 GMT", "version": "v2" }, { "created": "Wed, 11 Sep 2002 18:50:20 GMT", "version": "v3" } ]
2009-11-07
[ [ "King", "S. F.", "" ] ]
Recent SNO results strongly favour the large mixing angle (LMA) MSW solar solution. We argue that there are only two technically natural low energy neutrino mass matrix structures consistent with the LMA MSW solution, corresponding to either a hierarchy or an inverted hierarchy with pseudo-Dirac neutrinos. We first present a model-independent analysis in which we diagonalise each of these two mass matrix structures to leading order in $\theta_{13}$ and extract the neutrino masses, mixing angles and phases. In this analysis we express the MNS matrix to leading order in the small angle $\theta_{13}$ including the neutrino {\em and} charged lepton mixing angles and phases, the latter playing a crucial r\^{o}le for allowing the inverted hierarchy case to be consistent with the LMA MSW solution. We then consider the see-saw mechanism with right-handed neutrino dominance and show how the successful neutrino mass matrix structures may be constructed with no tuning and with small radiative corrections, leading to a full, partial or inverted neutrino mass hierarchy. In each case we derive approximate analytic relations between the input see-saw parameters and the resulting neutrino masses, mixing angles and phases, which will provide a useful guide for unified model building. For the hierarchical cases the LMA MSW solution gives a soft lower bound $|U_{e3}|\simgt 0.1$, just below the current CHOOZ limit. Both hierarchical and inverted hierarchical cases predict small $\beta \beta_{0\nu}$ with $|m_{ee}|\sim 0.01$ eV within the sensitivity of future proposals such as GENIUS. Successful leptogenesis is possible if the dominant right-handed neutrino is the heaviest one, but the leptogenesis phase is unrelated to the MNS phases.
hep-ph/9904293
D. Ghilencea
D. Ghilencea
Prediction for $\alpha_3(M_z)$ in a string-inspired model
9 pages, LaTeX, 3 figures
Phys.Lett. B459 (1999) 540-548
10.1016/S0370-2693(99)00695-4
OUTP-99-21-P(1999)
hep-ph
null
We apply the Renormalisation Group Evolution (RGE) to analyze the phenomenological implications of an extended supersymmetric model, for the value of the unification scale and the strong coupling at the electroweak scale. The model we consider is predicted to exist in Calabi-Yau string compactifications with Wilson line mechanism for $E_6$ symmetry breaking, contains additional matter beyond the MSSM spectrum and avoids the ``doublet-triplet'' splitting problem in the Higgs sector. The calculation is analytical in two-loop order and includes the effects of the heavy thresholds due to the additional matter considered. The value of $\alpha_3(M_z)$ can be brought within the experimental limits without a significant change of the unification scale from the MSSM prediction.
[ { "created": "Sat, 10 Apr 1999 13:34:31 GMT", "version": "v1" }, { "created": "Tue, 25 May 1999 18:27:09 GMT", "version": "v2" } ]
2009-10-31
[ [ "Ghilencea", "D.", "" ] ]
We apply the Renormalisation Group Evolution (RGE) to analyze the phenomenological implications of an extended supersymmetric model, for the value of the unification scale and the strong coupling at the electroweak scale. The model we consider is predicted to exist in Calabi-Yau string compactifications with Wilson line mechanism for $E_6$ symmetry breaking, contains additional matter beyond the MSSM spectrum and avoids the ``doublet-triplet'' splitting problem in the Higgs sector. The calculation is analytical in two-loop order and includes the effects of the heavy thresholds due to the additional matter considered. The value of $\alpha_3(M_z)$ can be brought within the experimental limits without a significant change of the unification scale from the MSSM prediction.
1303.1811
David B. Kaplan
Sichun Sun, David B.Kaplan, Ann E. Nelson
Little flavor: A model of weak-scale flavor physics
17 pages, 3 figures. Minor revisions to align with version accepted for publication, including title, and additional discussion about phenomenology
null
10.1103/PhysRevD.87.125036
INT-PUB-13-010, NSF-KITP-13-037
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe a model of quarks which identifies the large global symmetries of little Higgs models with the global flavor symmetries that arise in a deconstruction of the extra-dimensional 'topological insulator' model of flavor. The nonlinearly realized symmetries of little Higgs theories play a critical role in determining the flavor structure of fermion masses and mixing. All flavor physics occurs at the few TeV scale in this model, yet flavor changing neutral currents arising from the new physics are naturally smaller than those generated radiatively in the standard model, without having to invoke minimal flavor violation.
[ { "created": "Thu, 7 Mar 2013 20:55:40 GMT", "version": "v1" }, { "created": "Wed, 20 Mar 2013 00:14:47 GMT", "version": "v2" }, { "created": "Tue, 25 Jun 2013 23:47:12 GMT", "version": "v3" } ]
2013-08-09
[ [ "Sun", "Sichun", "" ], [ "Kaplan", "David B.", "" ], [ "Nelson", "Ann E.", "" ] ]
We describe a model of quarks which identifies the large global symmetries of little Higgs models with the global flavor symmetries that arise in a deconstruction of the extra-dimensional 'topological insulator' model of flavor. The nonlinearly realized symmetries of little Higgs theories play a critical role in determining the flavor structure of fermion masses and mixing. All flavor physics occurs at the few TeV scale in this model, yet flavor changing neutral currents arising from the new physics are naturally smaller than those generated radiatively in the standard model, without having to invoke minimal flavor violation.
hep-ph/9901303
Robert Brandenberger
Robert H. Brandenberger
Dynamical Breaking of CPT and Baryogenesis
12 pages, 1 figure invited talk at the Workshop on CPT and Lorentz Symmetry, Bloomington, Indiana, Nov. 6 - 8 1998, to be publ. in the proceedings (World Scientific, Singapore, 1999)
null
null
BROWN-HET-1163
hep-ph astro-ph hep-th
null
The asymmetry between matter and antimatter in the Universe indicates that there was a period in the very early Universe when the CPT symmetry was broken. The conservative interpretation is that the breaking was dynamical, induced by the distinguished direction of time stemming from the cosmological expansion. Here, I review the role which topological defect networks may play in baryogenesis and how this relates to dynamical CPT symmetry breaking. Particular attention is placed on defect-mediated electroweak baryogenesis. A recent suggestion of defect-mediated QCD scale baryogenesis is also mentioned.
[ { "created": "Thu, 14 Jan 1999 02:07:57 GMT", "version": "v1" } ]
2007-05-23
[ [ "Brandenberger", "Robert H.", "" ] ]
The asymmetry between matter and antimatter in the Universe indicates that there was a period in the very early Universe when the CPT symmetry was broken. The conservative interpretation is that the breaking was dynamical, induced by the distinguished direction of time stemming from the cosmological expansion. Here, I review the role which topological defect networks may play in baryogenesis and how this relates to dynamical CPT symmetry breaking. Particular attention is placed on defect-mediated electroweak baryogenesis. A recent suggestion of defect-mediated QCD scale baryogenesis is also mentioned.
hep-ph/0612041
Domenico Falcone
D.Falcone
Seesaw mechanism and leptogenesis
11 pages, RevTex4. Presented at the Laboratoire de Physique Theorique, Orsay, France
null
null
null
hep-ph
null
A brief overview of the phenomenology related to the seesaw mechanism and the baryogenesis via leptogenesis is presented. In particular, it is explained how large but not maximal lepton mixing can be achieved within the type II seesaw mechanism. Moreover, the consequences for leptogenesis are explored, including flavor effects.
[ { "created": "Tue, 5 Dec 2006 12:36:34 GMT", "version": "v1" } ]
2007-05-23
[ [ "Falcone", "D.", "" ] ]
A brief overview of the phenomenology related to the seesaw mechanism and the baryogenesis via leptogenesis is presented. In particular, it is explained how large but not maximal lepton mixing can be achieved within the type II seesaw mechanism. Moreover, the consequences for leptogenesis are explored, including flavor effects.
2106.10628
C. Q. Geng
C.Q. Geng and Chia-Wei Liu
Searching for possible evidences of new physics in $B\to V_1 V_2$
20 pages, 1 figure, revised version accepted by PLB
null
10.1016/j.physletb.2022.136883
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We explore the decays of $B\to V_1V_2$ ($V_{1,2}= (\rho, \omega,K^*, \phi)$ and $B= (B^0, B^+,B_s)$) with transverse polarizations. We explicitly evaluate the eigenstates of T-odd scalar operators involving spins for the first time, which offer physical insight among the T violating observables. Based on the helicity suppression of tree operators for transverse polarizations in the standard model (SM), we deduce that $\Delta \phi _p= \Delta \phi_\parallel - \Delta \phi_\perp=0$ with $\Delta\phi_{\perp,\parallel}$ the weak phases of the transverse amplitudes. In contrast, the experiments show that $\Delta \phi _p (B^0 \to K^{*0} \omega)= -0.84\pm 0.54$, which could be a signal of new physics. There is also a discrepancy between our result in the SM and the experimental data for the transverse polarized branching ratio in $B^0 \to K^{*0} \omega$. In addition, by counting the helicity flips, we argue that $\sin(\phi_\parallel - \phi_\perp ) \approx 0$, which meets well with most of the experiments except for the ones with $B^0\to K^{*0}\omega$, where $\phi_{\parallel,\perp}$ are the strong phases in the transverse amplitudes.
[ { "created": "Sun, 20 Jun 2021 05:26:30 GMT", "version": "v1" }, { "created": "Wed, 5 Jan 2022 06:49:04 GMT", "version": "v2" } ]
2022-01-12
[ [ "Geng", "C. Q.", "" ], [ "Liu", "Chia-Wei", "" ] ]
We explore the decays of $B\to V_1V_2$ ($V_{1,2}= (\rho, \omega,K^*, \phi)$ and $B= (B^0, B^+,B_s)$) with transverse polarizations. We explicitly evaluate the eigenstates of T-odd scalar operators involving spins for the first time, which offer physical insight among the T violating observables. Based on the helicity suppression of tree operators for transverse polarizations in the standard model (SM), we deduce that $\Delta \phi _p= \Delta \phi_\parallel - \Delta \phi_\perp=0$ with $\Delta\phi_{\perp,\parallel}$ the weak phases of the transverse amplitudes. In contrast, the experiments show that $\Delta \phi _p (B^0 \to K^{*0} \omega)= -0.84\pm 0.54$, which could be a signal of new physics. There is also a discrepancy between our result in the SM and the experimental data for the transverse polarized branching ratio in $B^0 \to K^{*0} \omega$. In addition, by counting the helicity flips, we argue that $\sin(\phi_\parallel - \phi_\perp ) \approx 0$, which meets well with most of the experiments except for the ones with $B^0\to K^{*0}\omega$, where $\phi_{\parallel,\perp}$ are the strong phases in the transverse amplitudes.
1909.03901
Li-Ping He
Eric Braaten, Li-Ping He, Kevin Ingles
Production of $X(3872)$ and a Photon in $e^+e^-$ Annihilation
26 pages, 11 figures. arXiv admin note: text overlap with arXiv:1904.12915
Phys. Rev. D 101, 014021 (2020)
10.1103/PhysRevD.101.014021
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If the $X(3872)$ is a weakly bound charm-meson molecule, it can be produced in $e^+ e^-$ annihilation by the creation of $D^{*0} \bar D^{*0}$ from a virtual photon followed by the rescattering of the P-wave charm-meson pair into the $X$ and a photon. A triangle singularity produces a narrow peak in the cross section for $e^+ e^- \to X \gamma$ 2.2 MeV above the $D^{*0} \bar{D}^{*0}$ threshold. We predict the normalized cross section in the region of the peak. We show that the absorptive contribution to the cross section for $e^+ e^- \to D^{*0} \bar D^{*0} \to X \gamma$, which was calculated previously by Dubynskiy and Voloshin, does not give a good approximation to the peak from the triangle singularity.
[ { "created": "Thu, 5 Sep 2019 20:44:54 GMT", "version": "v1" }, { "created": "Fri, 22 Nov 2019 21:29:08 GMT", "version": "v2" } ]
2020-02-05
[ [ "Braaten", "Eric", "" ], [ "He", "Li-Ping", "" ], [ "Ingles", "Kevin", "" ] ]
If the $X(3872)$ is a weakly bound charm-meson molecule, it can be produced in $e^+ e^-$ annihilation by the creation of $D^{*0} \bar D^{*0}$ from a virtual photon followed by the rescattering of the P-wave charm-meson pair into the $X$ and a photon. A triangle singularity produces a narrow peak in the cross section for $e^+ e^- \to X \gamma$ 2.2 MeV above the $D^{*0} \bar{D}^{*0}$ threshold. We predict the normalized cross section in the region of the peak. We show that the absorptive contribution to the cross section for $e^+ e^- \to D^{*0} \bar D^{*0} \to X \gamma$, which was calculated previously by Dubynskiy and Voloshin, does not give a good approximation to the peak from the triangle singularity.
hep-ph/0104313
Chun Bin Yang
C.B. Yang, X. Cai (Hua-Zhong Normal Univ.) and Z.M. Zhou
Understanding $K/\pi$ ratio distribution in the mixed events
11 pages in revtex, 8 eps figures included
J.Phys.G28:1-14,2002
10.1088/0954-3899/28/1/301
null
hep-ph
null
The event mixing method is analyzed for the study of the event-by-event $K/\pi$ ratio distribution. It is shown that there exists some correlation between the kaon and pion multiplicities in the mixed events. The $K/\pi$ ratio distributions in the mixed events for different sets of real events are shown. The dependence of the distributions on the mean $K/\pi$ ratio, mean and variance of multiplicity distribution in the real events is investigated systematically. The effect of imperfect particle identification on the $K/\pi$ ratio distribution in the mixed event is also considered.
[ { "created": "Mon, 30 Apr 2001 19:05:28 GMT", "version": "v1" } ]
2008-11-26
[ [ "Yang", "C. B.", "", "Hua-Zhong Normal Univ." ], [ "Cai", "X.", "", "Hua-Zhong Normal Univ." ], [ "Zhou", "Z. M.", "" ] ]
The event mixing method is analyzed for the study of the event-by-event $K/\pi$ ratio distribution. It is shown that there exists some correlation between the kaon and pion multiplicities in the mixed events. The $K/\pi$ ratio distributions in the mixed events for different sets of real events are shown. The dependence of the distributions on the mean $K/\pi$ ratio, mean and variance of multiplicity distribution in the real events is investigated systematically. The effect of imperfect particle identification on the $K/\pi$ ratio distribution in the mixed event is also considered.
1712.06588
Maxim Dvornikov
Maxim Dvornikov (IZMIRAN, Tomsk State University)
Magnetic field generation in dense gas of massive electrons with anomalous magnetic moments electroweakly interacting with background matter
3 pages in LaTeX, 2 eps figures; Contribution to the proceedings of 18th Lomonosov Conference on Elementary Particle Physics (Moscow, Russia, August 24-30, 2017)
Particle Physics at the Silver Jubilee of Lomonosov Conferences (Proceedings of the 18th Lomonosov Conference on Elementary Particle Physics), World Scientific, Singapore, 2019, pp. 385-387
10.1142/9789811202339_0070
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We describe the generation of the electric current flowing along the external magnetic field in the system of massive charged fermions, possessing anomalous magnetic moments and electroweakly interacting with background matter. This current is shown to result in the instability of the magnetic field leading to its growth. Some astrophysical applications are discussed.
[ { "created": "Sat, 16 Dec 2017 08:17:52 GMT", "version": "v1" } ]
2019-06-07
[ [ "Dvornikov", "Maxim", "", "IZMIRAN, Tomsk State University" ] ]
We describe the generation of the electric current flowing along the external magnetic field in the system of massive charged fermions, possessing anomalous magnetic moments and electroweakly interacting with background matter. This current is shown to result in the instability of the magnetic field leading to its growth. Some astrophysical applications are discussed.
2304.08964
Daniel Moreno Torres
Thomas Mannel, Daniel Moreno and Alexei A. Pivovarov
The heavy quark expansion for lifetimes: Towards the QCD corrections to power suppressed terms
17 pages, 8 figures
null
10.1103/PhysRevD.107.114026
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the Heavy Quark Expansion (HQE) for the nonleptonic decay rates of heavy hadrons, and compute the NLO QCD corrections to power terms up to order $1/m_Q^2$. We neglect the masses of the final-state quarks, so the application of our result is mainly for charmed hadrons. Our result can be applied also to bottomed hadrons as they constitute the main effect to this order up to corrections of $\mathcal{O}(m_c/m_b)$ and contributions due to penguin operators. We discuss the impact of our result for the lifetimes of heavy hadrons.
[ { "created": "Tue, 18 Apr 2023 12:57:51 GMT", "version": "v1" }, { "created": "Thu, 29 Jun 2023 13:10:56 GMT", "version": "v2" } ]
2023-07-05
[ [ "Mannel", "Thomas", "" ], [ "Moreno", "Daniel", "" ], [ "Pivovarov", "Alexei A.", "" ] ]
We consider the Heavy Quark Expansion (HQE) for the nonleptonic decay rates of heavy hadrons, and compute the NLO QCD corrections to power terms up to order $1/m_Q^2$. We neglect the masses of the final-state quarks, so the application of our result is mainly for charmed hadrons. Our result can be applied also to bottomed hadrons as they constitute the main effect to this order up to corrections of $\mathcal{O}(m_c/m_b)$ and contributions due to penguin operators. We discuss the impact of our result for the lifetimes of heavy hadrons.
2006.09386
Doojin Kim
Bhaskar Dutta, Doojin Kim, Shu Liao, Jong-Chul Park, Seodong Shin, Louis E. Strigari, Adrian Thompson
Searching for Dark Matter Signals in Timing Spectra at Neutrino Experiments
43 pages, 10 figures, 7 tables
null
null
MI-TH-2014
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The sensitivity to dark matter signals at neutrino experiments is fundamentally challenged by the neutrino rates, as they leave similar signatures in their detectors. As a way to improve the signal sensitivity, we investigate a dark matter search strategy which utilizes the timing and energy spectra to discriminate dark matter from neutrino signals at low-energy, pulsed-beam neutrino experiments. This strategy was proposed in our companion paper arXiv:1906.10745, which we apply to potential searches at COHERENT, JSNS$^2$, and CCM. These experiments are not only sources of neutrinos but also high intensity sources of photons. The dark matter candidate of interest comes from the relatively prompt decay of a dark sector gauge boson which may replace a Standard-Model photon, so the delayed neutrino events can be suppressed by keeping prompt events only. Furthermore, prompt neutrino events can be rejected by a cut in recoil energy spectra, as their incoming energy is relatively small and bounded from above while dark matter may deposit a sizable energy beyond it. We apply the search strategy of imposing a combination of energy and timing cuts to the existing CsI data of the COHERENT experiment as a concrete example, and report a mild excess beyond known backgrounds. We then investigate the expected sensitivity reaches to dark matter signals in our benchmark experiments.
[ { "created": "Tue, 16 Jun 2020 18:00:01 GMT", "version": "v1" } ]
2020-06-18
[ [ "Dutta", "Bhaskar", "" ], [ "Kim", "Doojin", "" ], [ "Liao", "Shu", "" ], [ "Park", "Jong-Chul", "" ], [ "Shin", "Seodong", "" ], [ "Strigari", "Louis E.", "" ], [ "Thompson", "Adrian", "" ] ]
The sensitivity to dark matter signals at neutrino experiments is fundamentally challenged by the neutrino rates, as they leave similar signatures in their detectors. As a way to improve the signal sensitivity, we investigate a dark matter search strategy which utilizes the timing and energy spectra to discriminate dark matter from neutrino signals at low-energy, pulsed-beam neutrino experiments. This strategy was proposed in our companion paper arXiv:1906.10745, which we apply to potential searches at COHERENT, JSNS$^2$, and CCM. These experiments are not only sources of neutrinos but also high intensity sources of photons. The dark matter candidate of interest comes from the relatively prompt decay of a dark sector gauge boson which may replace a Standard-Model photon, so the delayed neutrino events can be suppressed by keeping prompt events only. Furthermore, prompt neutrino events can be rejected by a cut in recoil energy spectra, as their incoming energy is relatively small and bounded from above while dark matter may deposit a sizable energy beyond it. We apply the search strategy of imposing a combination of energy and timing cuts to the existing CsI data of the COHERENT experiment as a concrete example, and report a mild excess beyond known backgrounds. We then investigate the expected sensitivity reaches to dark matter signals in our benchmark experiments.
1202.6422
Lei Guo
Su Ji-Juan, Guo Lei, Ma Wen-Gan, Zhang Ren-You, Ling Liu-Sheng, Han Liang
Next-to-leading order QCD predictions for $Z^0 H^0 + {\rm jet}$ production at LHC
18 pages, 7 figures
JHEP 03 (2012) 059
10.1007/JHEP03(2012)059
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the complete next-to-leading order (NLO) QCD corrections to the $Z^0H^0$ production in association with a jet at the LHC. We study the impacts of the NLO QCD radiative corrections to the integrated and differential cross sections and the dependence of the cross section on the factorization/renormalization scale. We present the transverse momentum distributions of the final $Z^0$-, Higgs-boson and leading-jet. We find that the NLO QCD corrections significantly modify the physical observables, and obviously reduce the scale uncertainty of the LO cross section. The QCD K-factors can be 1.183 and 1.180 at the $\sqrt{s}=14 TeV$ and $\sqrt{s}=7 TeV$ LHC respectively, when we adopt the inclusive event selection scheme with $p_{T,j}^{cut}=50 GeV$, $m_H=120 GeV$ and $\mu=\mu_r=\mu_f=\mu_0 \equiv 1/2(m_Z+m_H)$. Furthermore, we make the comparison between the two scale choices, $\mu=\mu_0$ and $\mu=\mu_1=1/2(E_{T}^{Z}+E_{T}^{H}+ \sum_{j}E_{T}^{jet})$, and find the scale choice $\mu=\mu_1$ seems to be more appropriate than the fixed scale $\mu=\mu_0$.
[ { "created": "Wed, 29 Feb 2012 01:33:31 GMT", "version": "v1" }, { "created": "Wed, 28 Mar 2012 06:58:18 GMT", "version": "v2" } ]
2012-03-29
[ [ "Ji-Juan", "Su", "" ], [ "Lei", "Guo", "" ], [ "Wen-Gan", "Ma", "" ], [ "Ren-You", "Zhang", "" ], [ "Liu-Sheng", "Ling", "" ], [ "Liang", "Han", "" ] ]
We calculate the complete next-to-leading order (NLO) QCD corrections to the $Z^0H^0$ production in association with a jet at the LHC. We study the impacts of the NLO QCD radiative corrections to the integrated and differential cross sections and the dependence of the cross section on the factorization/renormalization scale. We present the transverse momentum distributions of the final $Z^0$-, Higgs-boson and leading-jet. We find that the NLO QCD corrections significantly modify the physical observables, and obviously reduce the scale uncertainty of the LO cross section. The QCD K-factors can be 1.183 and 1.180 at the $\sqrt{s}=14 TeV$ and $\sqrt{s}=7 TeV$ LHC respectively, when we adopt the inclusive event selection scheme with $p_{T,j}^{cut}=50 GeV$, $m_H=120 GeV$ and $\mu=\mu_r=\mu_f=\mu_0 \equiv 1/2(m_Z+m_H)$. Furthermore, we make the comparison between the two scale choices, $\mu=\mu_0$ and $\mu=\mu_1=1/2(E_{T}^{Z}+E_{T}^{H}+ \sum_{j}E_{T}^{jet})$, and find the scale choice $\mu=\mu_1$ seems to be more appropriate than the fixed scale $\mu=\mu_0$.
hep-ph/9812323
Robin Stuart
Robin G. Stuart
Complete 2-loop quantum electrodynamic contributions to the muon lifetime in the Fermi model
9 pages, LaTeX, uses sprocl.sty, amsmath.sty, amssymb.sty and axodraw.sty. To appear in the Proceedings of the IVth International Symposium on Radiative Corrections (RADCOR98), Barcelona, Spain, 8-12 September, 1998, edited by J. Sola
null
null
UM-TH-98-19
hep-ph
null
The complete 2-loop QED contributions to the muon lifetime have been calculated analytically in the Fermi theory. The exact result for the effects of virtual and real photons, virtual electrons, muons and hadrons as well as e+e- pair creation is Delta Gamma^(2)=Gamma_0(alpha/pi)^2[(156815/5184)-(1036/27)zeta(2) -(895/36)zeta(3)+(67/8)zeta(4) +53zeta(2)ln(2)-(0.042+/-0.002)] where Gamma_0 is the tree-level width. This eliminates the theoretical error in the extracted value of the Fermi coupling constant, G_F, which was previously the source of the dominant uncertainty. The new value is G_F=(1.16637 +/- 0.00001) x 10^-5 GeV^-2 with the error being entirely experimental. Several experiments are planned for the next generation of muon lifetime measurements and these can proceed unhindered by theoretical uncertainties.
[ { "created": "Thu, 10 Dec 1998 16:34:58 GMT", "version": "v1" } ]
2007-05-23
[ [ "Stuart", "Robin G.", "" ] ]
The complete 2-loop QED contributions to the muon lifetime have been calculated analytically in the Fermi theory. The exact result for the effects of virtual and real photons, virtual electrons, muons and hadrons as well as e+e- pair creation is Delta Gamma^(2)=Gamma_0(alpha/pi)^2[(156815/5184)-(1036/27)zeta(2) -(895/36)zeta(3)+(67/8)zeta(4) +53zeta(2)ln(2)-(0.042+/-0.002)] where Gamma_0 is the tree-level width. This eliminates the theoretical error in the extracted value of the Fermi coupling constant, G_F, which was previously the source of the dominant uncertainty. The new value is G_F=(1.16637 +/- 0.00001) x 10^-5 GeV^-2 with the error being entirely experimental. Several experiments are planned for the next generation of muon lifetime measurements and these can proceed unhindered by theoretical uncertainties.
1301.1325
David G. Cerdeno
David G. Cerdeno, Pradipta Ghosh, Chan Beom Park
Probing the two light Higgs scenario in the NMSSM with a low-mass pseudoscalar
24 pages, 3 figures. Improved analysis. Final version to appear in JHEP
null
10.1007/JHEP06(2013)031
IFT-UAM/CSIC-13-002; FTUAM-13-124; CERN-PH-TH/2012-366
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this article we propose a simultaneous collider search strategy for a pair of scalar bosons in the NMSSM through the decays of a very light pseudoscalar. The massive scalar has a mass around 126 GeV while the lighter one can have a mass in the vicinity of 98 GeV (thus explaining an apparent LEP excess) or be much lighter. The successive decay of this scalar pair into two light pseudoscalars, followed by leptonic pseudoscalar decays, produces clean multi-lepton final states with small or no missing energy. Furthermore, this analysis offers an alternate leptonic probe for the 126 GeV scalar that can be comparable with the ZZ* search channel. We emphasize that a dedicated experimental search for multi-lepton final states can be an useful probe for this scenario and, in general, for the NMSSM Higgs sector. We illustrate our analysis with two representative benchmark points and show how the LHC configuration with 8 TeV center-of-mass energy and 25 inverse femtobarns of integrated luminosity can start testing this scenario, providing a good determination of the light pseudoscalar mass and a relatively good estimation of the lightest scalar mass.
[ { "created": "Mon, 7 Jan 2013 20:22:24 GMT", "version": "v1" }, { "created": "Mon, 14 Jan 2013 23:04:14 GMT", "version": "v2" }, { "created": "Mon, 20 May 2013 10:36:41 GMT", "version": "v3" } ]
2013-06-21
[ [ "Cerdeno", "David G.", "" ], [ "Ghosh", "Pradipta", "" ], [ "Park", "Chan Beom", "" ] ]
In this article we propose a simultaneous collider search strategy for a pair of scalar bosons in the NMSSM through the decays of a very light pseudoscalar. The massive scalar has a mass around 126 GeV while the lighter one can have a mass in the vicinity of 98 GeV (thus explaining an apparent LEP excess) or be much lighter. The successive decay of this scalar pair into two light pseudoscalars, followed by leptonic pseudoscalar decays, produces clean multi-lepton final states with small or no missing energy. Furthermore, this analysis offers an alternate leptonic probe for the 126 GeV scalar that can be comparable with the ZZ* search channel. We emphasize that a dedicated experimental search for multi-lepton final states can be an useful probe for this scenario and, in general, for the NMSSM Higgs sector. We illustrate our analysis with two representative benchmark points and show how the LHC configuration with 8 TeV center-of-mass energy and 25 inverse femtobarns of integrated luminosity can start testing this scenario, providing a good determination of the light pseudoscalar mass and a relatively good estimation of the lightest scalar mass.
hep-ph/9406257
Gilles Couture
G. Couture and S. Godfrey
Measurement of the WW-Gamma Vertex Through Single Photon Production at e^+ e^- Colliders
14 pages with 8 figures (available on request), preprint # OCIP/C 94-4, UQAM-PHE-94-09
Phys.Rev.D50:5607-5612,1994
10.1103/PhysRevD.50.5607
null
hep-ph
null
We perform a detailed study of the process $e^+e^-\to\gamma\nu_l\bar\nu_l$ and its sensitivity to anomalous gauge boson couplings of the $\gamma WW$ vertex. We concentrate on LEP II energies, $\sqrt{s}=200$ GeV, and energies appropria- te to the proposed Next Linear Collider (NLC) high energy $e^+e^-$ collider with c.m. energies of 500 GeV and 1 TeV. At 200 GeV, the process offers, at best, a consistency check of other processes being considered at LEP-200. At 500 GeV, the parameters $\kappa_\gamma$ and $\lambda_\gamma$ can be measured to about $\pm 0.05$ and $\pm 0.1$ respectively at 95\% C.L. while at 1 TeV, they can be measured to about $\pm 0.02$. At the high luminosities anticipa- ted at high energy linear colliders precision measurements are likely to be limited by systematic rather than statistical errors.
[ { "created": "Wed, 8 Jun 1994 20:44:45 GMT", "version": "v1" } ]
2014-11-17
[ [ "Couture", "G.", "" ], [ "Godfrey", "S.", "" ] ]
We perform a detailed study of the process $e^+e^-\to\gamma\nu_l\bar\nu_l$ and its sensitivity to anomalous gauge boson couplings of the $\gamma WW$ vertex. We concentrate on LEP II energies, $\sqrt{s}=200$ GeV, and energies appropria- te to the proposed Next Linear Collider (NLC) high energy $e^+e^-$ collider with c.m. energies of 500 GeV and 1 TeV. At 200 GeV, the process offers, at best, a consistency check of other processes being considered at LEP-200. At 500 GeV, the parameters $\kappa_\gamma$ and $\lambda_\gamma$ can be measured to about $\pm 0.05$ and $\pm 0.1$ respectively at 95\% C.L. while at 1 TeV, they can be measured to about $\pm 0.02$. At the high luminosities anticipa- ted at high energy linear colliders precision measurements are likely to be limited by systematic rather than statistical errors.
2403.12623
Sam Van Thurenhout
G. Somogyi and S. Van Thurenhout
All-order Feynman rules for leading-twist gauge-invariant operators in QCD
22 pages, LaTex, 9 figures, v2: major revision: conventions for quark operator rules changed and Feynman rules for gluon operators were added
Eur.Phys.J.C 84 (2024) 7, 740
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the Feynman rules for leading-twist gauge-invariant quark and gluon operators with an arbitrary number of total derivatives and applicable to any order in perturbation theory. This generalizes previous results and constitutes a necessary ingredient in the computation of the matrix elements of the corresponding operators. The results are written in a form appropriate for implementation in a computer algebra system. To illustrate the latter we provide implementations in Mathematica and FORM, which are made available at https://github.com/vtsam/NKLO.
[ { "created": "Tue, 19 Mar 2024 10:47:59 GMT", "version": "v1" }, { "created": "Thu, 13 Jun 2024 15:39:35 GMT", "version": "v2" } ]
2024-08-05
[ [ "Somogyi", "G.", "" ], [ "Van Thurenhout", "S.", "" ] ]
We present the Feynman rules for leading-twist gauge-invariant quark and gluon operators with an arbitrary number of total derivatives and applicable to any order in perturbation theory. This generalizes previous results and constitutes a necessary ingredient in the computation of the matrix elements of the corresponding operators. The results are written in a form appropriate for implementation in a computer algebra system. To illustrate the latter we provide implementations in Mathematica and FORM, which are made available at https://github.com/vtsam/NKLO.
1403.6366
Daniel Boyanovsky
Daniel Boyanovsky, Louis Lello
Time evolution of cascade decay
typos corrected, references updated
New Journal of Physics 16 (2014) 063050
10.1088/1367-2630/16/6/063050
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study non-perturbatively the time evolution of cascade decay for generic fields $\pi \rightarrow \phi_1\phi_2\rightarrow \phi_2\chi_1\chi_2$ and obtain the time dependence of amplitudes and populations for the resonant and final states. We analyze in detail the different time scales and the manifestation of unitary time evolution in the dynamics of production and decay of resonant intermediate and final states. The probability of occupation (population) "flows" as a function of time from the initial to the final states. When the decay width of the parent particle $\Gamma_\pi$ is much larger than that of the intermediate resonant state $\Gamma_{\phi_1}$ there is a "bottleneck" in the flow, the population of resonant states builds up to a maximum at $t^* = \ln[\Gamma_\pi/\Gamma_{\phi_1}]/(\Gamma_\pi-\Gamma_{\phi_1})$ nearly saturating unitarity and decays to the final state on the longer time scale $1/\Gamma_{\phi_1}$. As a consequence of the wide separation of time scales in this case the cascade decay can be interpreted as evolving sequentially $\pi \rightarrow \phi_1\phi_2; ~ \phi_1\phi_2\rightarrow \phi_2\chi_1\chi_2$. In the opposite limit the population of resonances ($\phi_1$) does not build up substantially and the cascade decay proceeds almost directly from the initial parent to the final state without resulting in a large amplitude of the resonant state. An alternative but equivalent non-perturbative method useful in cosmology is presented. Possible phenomenological implications for heavy sterile neutrinos as resonant states and consequences of quantum entanglement and correlations in the final state are discussed.
[ { "created": "Tue, 25 Mar 2014 14:35:58 GMT", "version": "v1" }, { "created": "Wed, 25 Jun 2014 01:42:31 GMT", "version": "v2" } ]
2014-06-26
[ [ "Boyanovsky", "Daniel", "" ], [ "Lello", "Louis", "" ] ]
We study non-perturbatively the time evolution of cascade decay for generic fields $\pi \rightarrow \phi_1\phi_2\rightarrow \phi_2\chi_1\chi_2$ and obtain the time dependence of amplitudes and populations for the resonant and final states. We analyze in detail the different time scales and the manifestation of unitary time evolution in the dynamics of production and decay of resonant intermediate and final states. The probability of occupation (population) "flows" as a function of time from the initial to the final states. When the decay width of the parent particle $\Gamma_\pi$ is much larger than that of the intermediate resonant state $\Gamma_{\phi_1}$ there is a "bottleneck" in the flow, the population of resonant states builds up to a maximum at $t^* = \ln[\Gamma_\pi/\Gamma_{\phi_1}]/(\Gamma_\pi-\Gamma_{\phi_1})$ nearly saturating unitarity and decays to the final state on the longer time scale $1/\Gamma_{\phi_1}$. As a consequence of the wide separation of time scales in this case the cascade decay can be interpreted as evolving sequentially $\pi \rightarrow \phi_1\phi_2; ~ \phi_1\phi_2\rightarrow \phi_2\chi_1\chi_2$. In the opposite limit the population of resonances ($\phi_1$) does not build up substantially and the cascade decay proceeds almost directly from the initial parent to the final state without resulting in a large amplitude of the resonant state. An alternative but equivalent non-perturbative method useful in cosmology is presented. Possible phenomenological implications for heavy sterile neutrinos as resonant states and consequences of quantum entanglement and correlations in the final state are discussed.
hep-ph/0310315
Peter Zeiler Skands
P. Skands and T. Sj\"ostrand
Progress on Multiple Interactions
To appear in the proceedings of HEP 2003, 3pp
Eur.Phys.J.C33:s548-s550,2004
10.1140/epjcd/s2003-03-520-7
LU-TP-03-45
hep-ph
null
We report on the development of a new model for the underlying event in hadron-hadron collisions. The model includes parton showers for all interactions, as well as non-trivial flavour, momentum, and colour correlations between interaction initiators and beam remnant partons.
[ { "created": "Tue, 28 Oct 2003 15:15:32 GMT", "version": "v1" } ]
2009-12-15
[ [ "Skands", "P.", "" ], [ "Sjöstrand", "T.", "" ] ]
We report on the development of a new model for the underlying event in hadron-hadron collisions. The model includes parton showers for all interactions, as well as non-trivial flavour, momentum, and colour correlations between interaction initiators and beam remnant partons.
0905.1253
Xiaojun Bi
Xiao-Jun Bi, Robert Brandenberger, Paolo Gondolo, Tianjun Li, Qiang Yuan and Xinmin Zhang
Non-Thermal Production of WIMPs, Cosmic $e^\pm$ Excesses and $\gamma$-rays from the Galactic Center
23 pages, 2 figures
Phys.Rev.D80:103502,2009
10.1103/PhysRevD.80.103502
null
hep-ph astro-ph.HE
http://creativecommons.org/licenses/by/3.0/
In this paper we propose a dark matter model and study aspects of its phenomenology. Our model is based on a new dark matter sector with a U(1)' gauge symmetry plus a discrete symmetry added to the Standard Model of particle physics. The new fields of the dark matter sector have no hadronic charges and couple only to leptons. Our model can not only give rise to the observed neutrino mass hierarchy, but can also generate the baryon number asymmetry via non-thermal leptogenesis. The breaking of the new U(1)' symmetry produces cosmic strings. The dark matter particles are produced non-thermally from cosmic string loop decay which allows one to obtain sufficiently large annihilation cross sections to explain the observed cosmic ray positron and electron fluxes recently measured by the PAMELA, ATIC, PPB-BETS, Fermi-LAT, and HESS experiments while maintaining the required overall dark matter energy density. The high velocity of the dark matter particles from cosmic string loop decay leads to a low phase space density and thus to a dark matter profile with a constant density core in contrast to what happens in a scenario with thermally produced cold dark matter where the density keeps rising towards the center. As a result, the flux of gamma rays radiated from the final leptonic states of dark matter annihilation from the Galactic center is suppressed and satisfies the constraints from the HESS gamma-ray observations.
[ { "created": "Fri, 8 May 2009 13:51:12 GMT", "version": "v1" } ]
2010-04-15
[ [ "Bi", "Xiao-Jun", "" ], [ "Brandenberger", "Robert", "" ], [ "Gondolo", "Paolo", "" ], [ "Li", "Tianjun", "" ], [ "Yuan", "Qiang", "" ], [ "Zhang", "Xinmin", "" ] ]
In this paper we propose a dark matter model and study aspects of its phenomenology. Our model is based on a new dark matter sector with a U(1)' gauge symmetry plus a discrete symmetry added to the Standard Model of particle physics. The new fields of the dark matter sector have no hadronic charges and couple only to leptons. Our model can not only give rise to the observed neutrino mass hierarchy, but can also generate the baryon number asymmetry via non-thermal leptogenesis. The breaking of the new U(1)' symmetry produces cosmic strings. The dark matter particles are produced non-thermally from cosmic string loop decay which allows one to obtain sufficiently large annihilation cross sections to explain the observed cosmic ray positron and electron fluxes recently measured by the PAMELA, ATIC, PPB-BETS, Fermi-LAT, and HESS experiments while maintaining the required overall dark matter energy density. The high velocity of the dark matter particles from cosmic string loop decay leads to a low phase space density and thus to a dark matter profile with a constant density core in contrast to what happens in a scenario with thermally produced cold dark matter where the density keeps rising towards the center. As a result, the flux of gamma rays radiated from the final leptonic states of dark matter annihilation from the Galactic center is suppressed and satisfies the constraints from the HESS gamma-ray observations.
1405.5012
Keigo Sumita
Hiroyuki Abe, Tatsuo Kobayashi, Keigo Sumita and Yoshiyuki Tatsuta
Gaussian Froggatt-Nielsen mechanism on magnetized orbifolds
21 pages, 5 figures
Phys. Rev. D 90, 105006 (2014)
10.1103/PhysRevD.90.105006
WU-HEP-14-06, EPHOU-14-012
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the structure of Yukawa matrices derived from the supersymmetric Yang-Mills theory on magnetized orbifolds, which can realize the observed quark and charged lepton mass ratios as well as the CKM mixing angles, even with a small number of tunable parameters and without any critical fine-tuning. As a reason behind this, we find that the obtained Yukawa matrices possess a Froggatt-Nielsen like structure with Gaussian hierarchies, which provides a suitable texture for them favored by the experimental data.
[ { "created": "Tue, 20 May 2014 09:41:29 GMT", "version": "v1" } ]
2014-11-11
[ [ "Abe", "Hiroyuki", "" ], [ "Kobayashi", "Tatsuo", "" ], [ "Sumita", "Keigo", "" ], [ "Tatsuta", "Yoshiyuki", "" ] ]
We study the structure of Yukawa matrices derived from the supersymmetric Yang-Mills theory on magnetized orbifolds, which can realize the observed quark and charged lepton mass ratios as well as the CKM mixing angles, even with a small number of tunable parameters and without any critical fine-tuning. As a reason behind this, we find that the obtained Yukawa matrices possess a Froggatt-Nielsen like structure with Gaussian hierarchies, which provides a suitable texture for them favored by the experimental data.
hep-ph/9508337
Michael Klasen
M. Klasen and G. Kramer
Dijet Cross Sections at O($\alpha\alpha_s^2$) in Photon-Proton Collisions
11 pages, latex, 5 figures appended as uuencoded file
Phys.Lett. B366 (1996) 385-393
10.1016/0370-2693(95)01352-0
DESY 95-159
hep-ph
null
We have calculated inclusive two-jet production in low $Q^2$ $ep$ collisions at O($\alpha\alpha_s^2$) superimposing direct and resolved contributions. The results are compared with recent experimental data from the ZEUS collaboration at HERA.
[ { "created": "Mon, 21 Aug 1995 16:10:55 GMT", "version": "v1" } ]
2016-09-01
[ [ "Klasen", "M.", "" ], [ "Kramer", "G.", "" ] ]
We have calculated inclusive two-jet production in low $Q^2$ $ep$ collisions at O($\alpha\alpha_s^2$) superimposing direct and resolved contributions. The results are compared with recent experimental data from the ZEUS collaboration at HERA.
hep-ph/0510398
Jakub Narebski
Stanislaw D. Glazek and Jakub Narebski (Institute of Theoretical Physics, Warsaw University, Poland)
Special relativity in decays of hybrids
39 pages, 16 figures, 7 tables, 55 eps files included (v2: some further explanations added)
Acta Phys.Polon. B37 (2006) 389-426
null
IFT/24/2005
hep-ph
null
A decay of a heavy hybrid is expected to produce light mesons flying out with speeds comparable to the speed of light and phenomenological models of the decay must respect symmetries of special relativity. We study consequences of this requirement in a class of simple constituent models with spin. Our models respect boost symmetry because they conform to the rules of a boost-invariant renormalization group procedure for effective particles in light-front QCD. But rotational symmetry of the decay amplitude is not guaranteed and the parameters in the model wave functions must take special values in order to obtain the symmetry. When the effective interaction Hamiltonian responsible for a hybrid decay has the same structure as the gluon-quark-antiquark interaction term obtained by solving the renormalization group equations for Hamiltonians in first order perturbation theory, the non-relativistic image of a hybrid as built from a quark and an antiquark and a heavy gluon that typically resides between the quarks, cannot produce rotationally symmetric amplitude. However, there exists an alternative generic picture in the model that does satisfy the requirements of special relativity. Namely, the distance between the quark and antiquark must be much smaller than the distance between the gluon and the pair of quarks, as if a hybrid were similar to a gluonium in which one gluon is replaced by a quark-antiquark pair.
[ { "created": "Sat, 29 Oct 2005 12:51:16 GMT", "version": "v1" }, { "created": "Thu, 2 Feb 2006 18:02:03 GMT", "version": "v2" } ]
2007-05-23
[ [ "Glazek", "Stanislaw D.", "", "Institute of Theoretical\n Physics, Warsaw University, Poland" ], [ "Narebski", "Jakub", "", "Institute of Theoretical\n Physics, Warsaw University, Poland" ] ]
A decay of a heavy hybrid is expected to produce light mesons flying out with speeds comparable to the speed of light and phenomenological models of the decay must respect symmetries of special relativity. We study consequences of this requirement in a class of simple constituent models with spin. Our models respect boost symmetry because they conform to the rules of a boost-invariant renormalization group procedure for effective particles in light-front QCD. But rotational symmetry of the decay amplitude is not guaranteed and the parameters in the model wave functions must take special values in order to obtain the symmetry. When the effective interaction Hamiltonian responsible for a hybrid decay has the same structure as the gluon-quark-antiquark interaction term obtained by solving the renormalization group equations for Hamiltonians in first order perturbation theory, the non-relativistic image of a hybrid as built from a quark and an antiquark and a heavy gluon that typically resides between the quarks, cannot produce rotationally symmetric amplitude. However, there exists an alternative generic picture in the model that does satisfy the requirements of special relativity. Namely, the distance between the quark and antiquark must be much smaller than the distance between the gluon and the pair of quarks, as if a hybrid were similar to a gluonium in which one gluon is replaced by a quark-antiquark pair.
1106.1996
Chuan Hung Chen
Chuan-Hung Chen, C. S. Kim
$\Delta m_D$ and $\Delta \Gamma_D$ revisted
9 pages, 2 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The lifetime difference ($y_D=\Delta\Gamma_D/2\Gamma_D$) and mass difference ($x_D=\Delta m_D/\Gamma_D$) of neutral $D$ meson have been measured with $y_D=(0.80\pm 0.13)%$ and $x_D=(0.59 \pm 0.20)%$, respectively. Intriguingly, in contrast with the cases of $K$ and $B_q$ systems, the current data indicate that $y_D/x_D \sim 1$ and $y_D$ favors to be larger than $x_D$. For explaining the experimental indication, we here study the $D-\bar D$ oscillation in the framework of unparticle physics. We demonstrate that {\it the peculiar phase appearing in off-shell unparticle propagator} could play an important role on $x_D$ and $y_D$.
[ { "created": "Fri, 10 Jun 2011 09:54:59 GMT", "version": "v1" } ]
2011-06-13
[ [ "Chen", "Chuan-Hung", "" ], [ "Kim", "C. S.", "" ] ]
The lifetime difference ($y_D=\Delta\Gamma_D/2\Gamma_D$) and mass difference ($x_D=\Delta m_D/\Gamma_D$) of neutral $D$ meson have been measured with $y_D=(0.80\pm 0.13)%$ and $x_D=(0.59 \pm 0.20)%$, respectively. Intriguingly, in contrast with the cases of $K$ and $B_q$ systems, the current data indicate that $y_D/x_D \sim 1$ and $y_D$ favors to be larger than $x_D$. For explaining the experimental indication, we here study the $D-\bar D$ oscillation in the framework of unparticle physics. We demonstrate that {\it the peculiar phase appearing in off-shell unparticle propagator} could play an important role on $x_D$ and $y_D$.
1610.08546
Mariola Klusek-Gawenda
Mariola Klusek-Gawenda and Antoni Szczurek
Diphoton production in lead-lead and proton-proton UPC
9 pages, 8 figures, talk given by M.K-G at the Low-x Meeting 2016, 6-11 June 2016, K\'aroly R\'obert College, Gy\"ongy\"os, Hungary. arXiv admin note: substantial text overlap with arXiv:1606.09038
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss diphoton semi(exclusive) production in ultraperipheral $PbPb$ collisions at energy of $\sqrt{s_{NN}}=$ 5.5 TeV (LHC). The nuclear calculations are based on equivalent photon approximation in the impact parameter space. The cross sections for elementary $\gamma \gamma \to \gamma \gamma$ subprocess are calculated including three different mechanisms: box diagrams with leptons and quarks in the loops, a VDM-Regge contribution with virtual intermediate hadronic excitations of the photons and the two-gluon exchange contribution (formally three-loops) to elastic photon-photon scattering in the high-energy approximation. We got relatively high cross sections in $PbPb$ collisions ($306$ nb). This opens a possibility to study the $\gamma \gamma \to \gamma \gamma$ (quasi)elastic scattering at the LHC. We find that the cross section for elastic $\gamma\gamma$ scattering could be measured in the lead-lead collisions for the diphoton invariant mass up to $W_{\gamma\gamma} \approx 15-20$ GeV. We identify region(s) of phase space where the two-gluon exchange contribution becomes important ingredient compared to box and nonperturbative VDM-Regge mechanisms. We perform a similar analysis for the $pp \to pp\gamma\gamma$ reaction at energy of $\sqrt{s_{NN}}=7$ and $100$ TeV.
[ { "created": "Wed, 26 Oct 2016 20:55:36 GMT", "version": "v1" } ]
2016-10-28
[ [ "Klusek-Gawenda", "Mariola", "" ], [ "Szczurek", "Antoni", "" ] ]
We discuss diphoton semi(exclusive) production in ultraperipheral $PbPb$ collisions at energy of $\sqrt{s_{NN}}=$ 5.5 TeV (LHC). The nuclear calculations are based on equivalent photon approximation in the impact parameter space. The cross sections for elementary $\gamma \gamma \to \gamma \gamma$ subprocess are calculated including three different mechanisms: box diagrams with leptons and quarks in the loops, a VDM-Regge contribution with virtual intermediate hadronic excitations of the photons and the two-gluon exchange contribution (formally three-loops) to elastic photon-photon scattering in the high-energy approximation. We got relatively high cross sections in $PbPb$ collisions ($306$ nb). This opens a possibility to study the $\gamma \gamma \to \gamma \gamma$ (quasi)elastic scattering at the LHC. We find that the cross section for elastic $\gamma\gamma$ scattering could be measured in the lead-lead collisions for the diphoton invariant mass up to $W_{\gamma\gamma} \approx 15-20$ GeV. We identify region(s) of phase space where the two-gluon exchange contribution becomes important ingredient compared to box and nonperturbative VDM-Regge mechanisms. We perform a similar analysis for the $pp \to pp\gamma\gamma$ reaction at energy of $\sqrt{s_{NN}}=7$ and $100$ TeV.
hep-ph/0002254
null
Giancarlo D'Ambrosio (INFN-Sezione di Napoli)
Theory of rare kaon decays
11 pages Latex file, no figures;Invited plenary talk at the 3rd International Conference on B Physics and CP Violation (BCONF99), Taipei, Taiwan, 3-7 Dec 1999
null
10.1142/9789812791870_0048
null
hep-ph
null
We review some recent theoretical results on rare kaon decays. Particular attention is devoted to find Standard Model tests. This is theoretically easy in $K\to \pi \nu \bar{\nu}$, while a careful study of the long distance contributions is needed for $K_{L}\to \pi ^{0}e% \bar{e}$, $K_{L}\to \mu \bar{\mu}$ and $K\to \pi \pi \gamma$
[ { "created": "Thu, 24 Feb 2000 17:57:41 GMT", "version": "v1" } ]
2016-11-23
[ [ "D'Ambrosio", "Giancarlo", "", "INFN-Sezione di Napoli" ] ]
We review some recent theoretical results on rare kaon decays. Particular attention is devoted to find Standard Model tests. This is theoretically easy in $K\to \pi \nu \bar{\nu}$, while a careful study of the long distance contributions is needed for $K_{L}\to \pi ^{0}e% \bar{e}$, $K_{L}\to \mu \bar{\mu}$ and $K\to \pi \pi \gamma$
2207.01032
Masashi Aiko
Masashi Aiko, Shinya Kanemura, Kodai Sakurai
Radiative corrections to decay branching ratios of the CP-odd Higgs boson in two Higgs doublet models
63 pages, 19 figures, version accepted by Nuclear Physics B. arXiv admin note: text overlap with arXiv:2108.11868
null
10.1016/j.nuclphysb.2022.116047
KEK-TH 2438, OU-HET 1150, TU 1162
hep-ph
http://creativecommons.org/licenses/by/4.0/
We calculate radiative corrections to decay rates of CP-odd Higgs boson $A$ for various decay modes in the four types of two Higgs doublet models with the softly broken discrete $Z_{2}$ symmetry. The decay branching ratios are evaluated at the next-to-leading order for electroweak corrections and the next-to-next-to-leading order for QCD corrections. We comprehensively study the impact of the electroweak corrections on the decay rates and the branching ratios. We find that the radiative corrections can sizably modify the branching ratios, especially for the $A\to Zh$ decay mode in the nearly alignment scenario, where coupling constants of the SM-like Higgs boson $h$ are close to those in the standard model. We also show correlations between the branching ratios of $A$ and the scaling factor of the SM-like Higgs boson coupling including higher-order corrections. In addition, we show characteristic predictions on the decay pattern depending on the types of Yukawa interaction, by which we can discriminate the types of Yukawa interaction in future collider experiments.
[ { "created": "Sun, 3 Jul 2022 13:06:23 GMT", "version": "v1" }, { "created": "Wed, 14 Dec 2022 09:28:13 GMT", "version": "v2" } ]
2023-01-04
[ [ "Aiko", "Masashi", "" ], [ "Kanemura", "Shinya", "" ], [ "Sakurai", "Kodai", "" ] ]
We calculate radiative corrections to decay rates of CP-odd Higgs boson $A$ for various decay modes in the four types of two Higgs doublet models with the softly broken discrete $Z_{2}$ symmetry. The decay branching ratios are evaluated at the next-to-leading order for electroweak corrections and the next-to-next-to-leading order for QCD corrections. We comprehensively study the impact of the electroweak corrections on the decay rates and the branching ratios. We find that the radiative corrections can sizably modify the branching ratios, especially for the $A\to Zh$ decay mode in the nearly alignment scenario, where coupling constants of the SM-like Higgs boson $h$ are close to those in the standard model. We also show correlations between the branching ratios of $A$ and the scaling factor of the SM-like Higgs boson coupling including higher-order corrections. In addition, we show characteristic predictions on the decay pattern depending on the types of Yukawa interaction, by which we can discriminate the types of Yukawa interaction in future collider experiments.
0901.0052
Kwang Sik Jeong
Kiwoon Choi, Kwang Sik Jeong, Shuntaro Nakamura, Ken-Ichi Okumura, Masahiro Yamaguchi
Sparticle masses in deflected mirage mediation
43 pages, 17 figures, references added
JHEP 0904:107,2009
10.1088/1126-6708/2009/04/107
KIAS-P08085, TU-835
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the sparticle mass patterns that can be realized in deflected mirage mediation scenario of supersymmetry breaking, in which the moduli, anomaly, and gauge mediations all contribute to the MSSM soft parameters. Analytic expression of low energy soft parameters and also the sfermion mass sum rules are derived, which can be used to interpret the experimentally measured sparticle masses within the framework of the most general mixed moduli-gauge-anomaly mediation. Phenomenological aspects of some specific examples are also discussed.
[ { "created": "Wed, 31 Dec 2008 04:13:42 GMT", "version": "v1" }, { "created": "Mon, 19 Jan 2009 00:54:48 GMT", "version": "v2" } ]
2009-05-01
[ [ "Choi", "Kiwoon", "" ], [ "Jeong", "Kwang Sik", "" ], [ "Nakamura", "Shuntaro", "" ], [ "Okumura", "Ken-Ichi", "" ], [ "Yamaguchi", "Masahiro", "" ] ]
We discuss the sparticle mass patterns that can be realized in deflected mirage mediation scenario of supersymmetry breaking, in which the moduli, anomaly, and gauge mediations all contribute to the MSSM soft parameters. Analytic expression of low energy soft parameters and also the sfermion mass sum rules are derived, which can be used to interpret the experimentally measured sparticle masses within the framework of the most general mixed moduli-gauge-anomaly mediation. Phenomenological aspects of some specific examples are also discussed.
hep-ph/9705223
Huang Ming-qiu
Yuan-ben Dai, Chao-shang Huang, Ming-qiu Huang, Hong-Ying Jin and Chun Liu
Decay Widths of Excited Heavy Mesons From QCD Sum Rules at the Leading Order of HQET
RevTeX, 16 pages including 1 figure; minor changes, final version to appear in Physical Review D
Phys.Rev.D58:094032,1998; Erratum-ibid.D59:059901,1999
10.1103/PhysRevD.58.094032 10.1103/PhysRevD.59.059901
BIHEP-TH-97-005, AS-ITP-97-12, SNUTP 97-049
hep-ph
null
The widths for pionic decays of lowest two excited doublets (0^+,1^+) and (1^+,2^+) of heavy mesons are studied with QCD sum rules in the leading order of heavy quark effective theory. The ambiguity due to presence of two distinct 1^+ states are solved. The soft pion approximation is not used.
[ { "created": "Sun, 4 May 1997 07:59:57 GMT", "version": "v1" }, { "created": "Thu, 30 Apr 1998 03:01:40 GMT", "version": "v2" }, { "created": "Tue, 18 Aug 1998 07:53:59 GMT", "version": "v3" } ]
2014-11-17
[ [ "Dai", "Yuan-ben", "" ], [ "Huang", "Chao-shang", "" ], [ "Huang", "Ming-qiu", "" ], [ "Jin", "Hong-Ying", "" ], [ "Liu", "Chun", "" ] ]
The widths for pionic decays of lowest two excited doublets (0^+,1^+) and (1^+,2^+) of heavy mesons are studied with QCD sum rules in the leading order of heavy quark effective theory. The ambiguity due to presence of two distinct 1^+ states are solved. The soft pion approximation is not used.
1906.01673
Lucas Johns
Lucas Johns
Neutrino oscillations in a trapping potential
14 pages, 0 figures
Int. J. Mod. Phys. A 34, 1950160 (2019)
10.1142/S0217751X19501604
null
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A number of derivations of the standard neutrino oscillation formula are known, each one providing its own unique insights. Common to all treatments is the assumption that neutrinos propagate freely between source and detector, as indeed they do in all experiments thus far conducted. Here we consider how neutrinos oscillate when, contrary to the usual set-up, they are bound in a potential well. The focus in particular is on nonrelativistic neutrinos with quasi-degenerate masses, for which oscillations in free space are described by the same formula, to lowest order, as relativistic neutrinos. Trapping these particles engenders corrections to their oscillation frequencies because the interference terms are between discrete energy levels rather than continuous spectra. Especially novel is the frequency shift that occurs due to the dependence of the energy levels on the mass of the neutrino: this part of the correction is nonvanishing even in the extremely nonrelativistic limit, reflecting the fact that the neutrino mass states have different zero-point energies in the well. Building an apparatus that can trap neutrinos is a futuristic prospect to say the least, but these calculations nonetheless shine a light on certain basic aspects of the flavor-oscillation phenomenon.
[ { "created": "Tue, 4 Jun 2019 18:36:50 GMT", "version": "v1" } ]
2019-10-08
[ [ "Johns", "Lucas", "" ] ]
A number of derivations of the standard neutrino oscillation formula are known, each one providing its own unique insights. Common to all treatments is the assumption that neutrinos propagate freely between source and detector, as indeed they do in all experiments thus far conducted. Here we consider how neutrinos oscillate when, contrary to the usual set-up, they are bound in a potential well. The focus in particular is on nonrelativistic neutrinos with quasi-degenerate masses, for which oscillations in free space are described by the same formula, to lowest order, as relativistic neutrinos. Trapping these particles engenders corrections to their oscillation frequencies because the interference terms are between discrete energy levels rather than continuous spectra. Especially novel is the frequency shift that occurs due to the dependence of the energy levels on the mass of the neutrino: this part of the correction is nonvanishing even in the extremely nonrelativistic limit, reflecting the fact that the neutrino mass states have different zero-point energies in the well. Building an apparatus that can trap neutrinos is a futuristic prospect to say the least, but these calculations nonetheless shine a light on certain basic aspects of the flavor-oscillation phenomenon.
2205.14243
Navin McGinnis
Radovan Dermisek, Keith Hermanek, Navin McGinnis, Sangsik Yoon
The Ellipse of Muon Dipole Moments
4 pages + references, 4 figures. v2: matches published version
null
10.1103/PhysRevLett.129.221801
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that any new interaction resulting in a chirally-enhanced contribution to the muon magnetic moment necessarily modifies the decay rate of the Higgs boson to muon pairs or generates the muon electric dipole moment. These three observables are highly correlated, and near future measurements of $h\to \mu^+\mu^-$ will carve an ellipse in the plane of dipole moments for any such model. Together with the future measurements of the electric dipole moment many models able to explain the muon g-2 anomaly can be efficiently tested.
[ { "created": "Fri, 27 May 2022 21:31:24 GMT", "version": "v1" }, { "created": "Wed, 23 Nov 2022 22:59:09 GMT", "version": "v2" } ]
2022-12-07
[ [ "Dermisek", "Radovan", "" ], [ "Hermanek", "Keith", "" ], [ "McGinnis", "Navin", "" ], [ "Yoon", "Sangsik", "" ] ]
We show that any new interaction resulting in a chirally-enhanced contribution to the muon magnetic moment necessarily modifies the decay rate of the Higgs boson to muon pairs or generates the muon electric dipole moment. These three observables are highly correlated, and near future measurements of $h\to \mu^+\mu^-$ will carve an ellipse in the plane of dipole moments for any such model. Together with the future measurements of the electric dipole moment many models able to explain the muon g-2 anomaly can be efficiently tested.
2310.16348
Maaz Hayat
Peter Cox, Matthew J. Dolan, Maaz Hayat, Andrea Thamm, Raymond R. Volkas
Classification of three-family flavoured DFSZ axion models that have no domain wall problem
20 pages, 3 tables, v2: references added, journal version
J. High Energ. Phys. 2024, 11 (2024)
10.1007/JHEP02(2024)011
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We provide an exhaustive classification of three-family DFSZ axion models that have no cosmological domain wall problem. This result is obtained by making the Peccei-Quinn symmetry flavour dependent in certain specific ways, thus reinforcing a possible connection between the strong CP problem and the flavour puzzle. Known DFSZ flavour variants such as the top-specific model emerge as special cases. Key features of the phenomenology of these models are briefly discussed.
[ { "created": "Wed, 25 Oct 2023 04:07:58 GMT", "version": "v1" }, { "created": "Tue, 6 Feb 2024 01:10:56 GMT", "version": "v2" } ]
2024-02-07
[ [ "Cox", "Peter", "" ], [ "Dolan", "Matthew J.", "" ], [ "Hayat", "Maaz", "" ], [ "Thamm", "Andrea", "" ], [ "Volkas", "Raymond R.", "" ] ]
We provide an exhaustive classification of three-family DFSZ axion models that have no cosmological domain wall problem. This result is obtained by making the Peccei-Quinn symmetry flavour dependent in certain specific ways, thus reinforcing a possible connection between the strong CP problem and the flavour puzzle. Known DFSZ flavour variants such as the top-specific model emerge as special cases. Key features of the phenomenology of these models are briefly discussed.
2010.06441
Carlos Henrique de Lima
Carlos Henrique de Lima, Ben Keeshan, Heather E. Logan and Yue Zhang
Probing Dark Sector CP Violation with Electric Dipole Moments and Colliders
19 pages, 6 figures, v2:references added, typos corrected, figure 4 corrected. v3: version to be published in PRD
Phys. Rev. D 103, 115034 (2021)
10.1103/PhysRevD.103.115034
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study the experimental constraints on dark sector CP violation that enters the visible sector through a Higgs portal coupling $H^{\dagger} H Z^{\prime}_{\mu\nu} \widetilde Z^{\prime \mu\nu}$, where the $Z^{\prime}$ is from a new U(1) gauge symmetry which is assumed to couple to lepton number. We compute explicitly the leading two-loop contribution of this effective operator to the electron electric dipole moment (EDM) and show that the resulting constraints are comparable to those from direct $Z^{\prime}$ searches at electron-positron colliders when the effective operator is generated at tree level. We also examine an explicit UV completion for this effective operator that was first introduced to achieve electroweak baryogenesis and show that collider constraints from $B$-factories already exclude viable baryogenesis for $Z^{\prime}$ masses below 10 GeV, and that future electron-positron Higgs factories will exclude viable baryogenesis for $Z^{\prime}$ masses up to the $e^+e^-$ center-of-mass energy if anticipated luminosities are achieved. For higher $Z^{\prime}$ masses, the full viable baryogenesis parameter space lies within six orders of magnitude of the current upper bound on the electron EDM.
[ { "created": "Tue, 13 Oct 2020 14:56:30 GMT", "version": "v1" }, { "created": "Mon, 9 Nov 2020 15:33:01 GMT", "version": "v2" }, { "created": "Wed, 9 Jun 2021 16:37:22 GMT", "version": "v3" } ]
2021-07-07
[ [ "de Lima", "Carlos Henrique", "" ], [ "Keeshan", "Ben", "" ], [ "Logan", "Heather E.", "" ], [ "Zhang", "Yue", "" ] ]
We study the experimental constraints on dark sector CP violation that enters the visible sector through a Higgs portal coupling $H^{\dagger} H Z^{\prime}_{\mu\nu} \widetilde Z^{\prime \mu\nu}$, where the $Z^{\prime}$ is from a new U(1) gauge symmetry which is assumed to couple to lepton number. We compute explicitly the leading two-loop contribution of this effective operator to the electron electric dipole moment (EDM) and show that the resulting constraints are comparable to those from direct $Z^{\prime}$ searches at electron-positron colliders when the effective operator is generated at tree level. We also examine an explicit UV completion for this effective operator that was first introduced to achieve electroweak baryogenesis and show that collider constraints from $B$-factories already exclude viable baryogenesis for $Z^{\prime}$ masses below 10 GeV, and that future electron-positron Higgs factories will exclude viable baryogenesis for $Z^{\prime}$ masses up to the $e^+e^-$ center-of-mass energy if anticipated luminosities are achieved. For higher $Z^{\prime}$ masses, the full viable baryogenesis parameter space lies within six orders of magnitude of the current upper bound on the electron EDM.
hep-ph/0409321
Ariel Megevand
Ariel Megevand, Francisco Astorga
Generation of baryon inhomogeneities in the electroweak phase transition
26 pages, 8 figures. Revised version, accepted for publication in Phys.Rev.D. Discussion on the effects on the quark-hadron phase transition improved and expanded; other explanatory comments and references added
Phys.Rev. D71 (2005) 023502
10.1103/PhysRevD.71.023502
null
hep-ph astro-ph hep-th
null
It is known that baryon number inhomogeneities may arise as a consequence of electroweak baryogenesis. Their geometry, size, and amplitude depend on the parameters that characterize the baryogenesis mechanism, as well as on those that determine the phase transition dynamics. We investigate this parametric dependance. We show that in the case of the minimal supersymmetric standard model, the geometry of the inhomogeneities most probably consists of spherical regions of high density surrounded by low-density walls, in contrast to the case of the minimal standard model. In this supersymmetric extension we find that density contrasts of up to a factor of 100 may arise. This amplitude increases for higher values of the latent heat or lower values of the bubble wall tension, and can be significantly larger in different extensions of the standard model. Such inhomogeneities may thus affect the dynamics of the subsequent quark-hadron phase transition.
[ { "created": "Tue, 28 Sep 2004 14:07:31 GMT", "version": "v1" }, { "created": "Wed, 22 Dec 2004 11:56:29 GMT", "version": "v2" } ]
2009-11-10
[ [ "Megevand", "Ariel", "" ], [ "Astorga", "Francisco", "" ] ]
It is known that baryon number inhomogeneities may arise as a consequence of electroweak baryogenesis. Their geometry, size, and amplitude depend on the parameters that characterize the baryogenesis mechanism, as well as on those that determine the phase transition dynamics. We investigate this parametric dependance. We show that in the case of the minimal supersymmetric standard model, the geometry of the inhomogeneities most probably consists of spherical regions of high density surrounded by low-density walls, in contrast to the case of the minimal standard model. In this supersymmetric extension we find that density contrasts of up to a factor of 100 may arise. This amplitude increases for higher values of the latent heat or lower values of the bubble wall tension, and can be significantly larger in different extensions of the standard model. Such inhomogeneities may thus affect the dynamics of the subsequent quark-hadron phase transition.
hep-ph/0007016
Gautam Bhattacharyya
Asmaa Abada and Gautam Bhattacharyya
Can R-parity violation explain the LSND data as well?
7 pages, Latex, 3 PS figures; in v2 a few clarifying remarks included and two references added (to appear in Physical Review D)
Phys.Rev. D63 (2001) 017701
10.1103/PhysRevD.63.017701
LPT Orsay/00-58, SINP/TNP/00-14
hep-ph
null
The recent Super-Kamiokande data now admit only one type of mass hierarchy in a framework with three active and one sterile neutrinos. We show that neutrino masses and mixings generated by R-parity-violating couplings, with values within their experimental upper limits, are capable of reproducing this hierarchy, explaining all neutrino data particularly after including the LSND results.
[ { "created": "Mon, 3 Jul 2000 17:09:00 GMT", "version": "v1" }, { "created": "Fri, 15 Sep 2000 09:25:31 GMT", "version": "v2" } ]
2009-10-31
[ [ "Abada", "Asmaa", "" ], [ "Bhattacharyya", "Gautam", "" ] ]
The recent Super-Kamiokande data now admit only one type of mass hierarchy in a framework with three active and one sterile neutrinos. We show that neutrino masses and mixings generated by R-parity-violating couplings, with values within their experimental upper limits, are capable of reproducing this hierarchy, explaining all neutrino data particularly after including the LSND results.
hep-ph/9706294
Yuan Feng
Feng Yuan and Kuang-Ta Chao (Peking University)
The Color-Octet intrinsic charm in $\eta^\prime$ and $B\to \eta^\prime X$ decays
9 pages, RevTex, 1 PS figure
Phys.Rev.D56:2495-2498,1997
10.1103/PhysRevD.56.R2495
PKU-TP-97-21
hep-ph
null
Color-octet mechanism for the decay B\to \eta^\prime X is proposed to explain the large branching ratio of Br(B\to \eta^\prime X)\sim 1\times 10^{-3} recently announced by CLEO. We argue that the inclusive \eta^\prime production in B decays may dominantly come from the Cabbibo favored b\to (\bar c c)_8s process where \bar c c pair is in a color-octet configuration, and followed by the nonperturbative transition (\bar c c)_8\to \eta^\prime X. The color-octet intrinsic charm component in the higher Fock states of \eta^\prime is crucial and is induced by the strong coupling of \eta^\prime to gluons via QCD axial anomaly.
[ { "created": "Mon, 9 Jun 1997 14:22:26 GMT", "version": "v1" } ]
2009-12-30
[ [ "Yuan", "Feng", "", "Peking University" ], [ "Chao", "Kuang-Ta", "", "Peking University" ] ]
Color-octet mechanism for the decay B\to \eta^\prime X is proposed to explain the large branching ratio of Br(B\to \eta^\prime X)\sim 1\times 10^{-3} recently announced by CLEO. We argue that the inclusive \eta^\prime production in B decays may dominantly come from the Cabbibo favored b\to (\bar c c)_8s process where \bar c c pair is in a color-octet configuration, and followed by the nonperturbative transition (\bar c c)_8\to \eta^\prime X. The color-octet intrinsic charm component in the higher Fock states of \eta^\prime is crucial and is induced by the strong coupling of \eta^\prime to gluons via QCD axial anomaly.
0710.3035
Grigorios Chachamis
Grigorios Chachamis
NNLO Virtual corrections to W+ W- production at the LHC
Presented at 31st International Conference of Theoretical Physics: Matter to the Deepest: Recent Development in Physics of Fundamental Interactions, Ustron, Katowice, Poland, 5-11 Sep 2007
Acta Phys.Polon.B38:3563-3568,2007
null
null
hep-ph
null
We report on a recent calculation of the two-loop virtual QCD corrections to the W boson pair production in the quark-anti-quark-annihilation channel in the limit where all kinematical invariants are large compared to the mass of the W boson. Our result is exact up to terms suppressed by powers of the W boson mass. The infrared pole structure is in agreement with the prediction of Catani's general formalism for the singularities of two-loop QCD amplitudes.
[ { "created": "Tue, 16 Oct 2007 16:51:44 GMT", "version": "v1" } ]
2008-12-30
[ [ "Chachamis", "Grigorios", "" ] ]
We report on a recent calculation of the two-loop virtual QCD corrections to the W boson pair production in the quark-anti-quark-annihilation channel in the limit where all kinematical invariants are large compared to the mass of the W boson. Our result is exact up to terms suppressed by powers of the W boson mass. The infrared pole structure is in agreement with the prediction of Catani's general formalism for the singularities of two-loop QCD amplitudes.
2307.02102
Juan M. Torres-Rincon
Juan M. Torres-Rincon, \`Angels Ramos and Laura Tolos
Femtoscopy of $D$ mesons and light mesons upon unitarized effective field theories
28 pages, 6 figures (data points in ancillary data). v2: Version accepted by Phys.Rev.D journal, containing additional references and providing the pole positions of the generated resonances by the off-shell T-matrix equation
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Hadron femtoscopy has turned into a powerful tool for accessing space-time information of heavy-ion collisions as well as for studying final-state interactions of hadrons. Recently, heavy-flavor femtoscopy has become feasible using the ALICE detector at the LHC. We compute the correlation function of $D$ mesons and light mesons using an off-shell $T$-matrix approach to access the two-meson wave function, and predict the correlation functions involving charged $D^+, D^{*+},D_s^+$ and $D_s^{*+}$ with $\pi^\pm$ and $K^\pm$. From the obtained results -- all of them accessible in $p+p$ collision experiments -- we point up the case of $D^+ \pi^-$, which is sensitive to the lower state of the two-pole $D_0^* (2300)$ system. The presence of such poles imprints a depletion on the correlation function, which could potentially be detected in experiments. While preliminary ALICE data do not show evidence of this effect, we suggest to look into the $D_s^+ K^-$ system to explore the higher pole of the $D_0^* (2300)$, as the depletion in the correlation function is more pronounced. Using heavy-quark spin symmetry we also propose exploring the effect of the two poles of the $D_1(2430)$ and predict similar structures in the correlation functions of the $D^{*+} \pi^-$ and $D_s^{*+} K^-$ pairs.
[ { "created": "Wed, 5 Jul 2023 08:22:29 GMT", "version": "v1" }, { "created": "Fri, 20 Oct 2023 14:44:57 GMT", "version": "v2" } ]
2023-10-23
[ [ "Torres-Rincon", "Juan M.", "" ], [ "Ramos", "Àngels", "" ], [ "Tolos", "Laura", "" ] ]
Hadron femtoscopy has turned into a powerful tool for accessing space-time information of heavy-ion collisions as well as for studying final-state interactions of hadrons. Recently, heavy-flavor femtoscopy has become feasible using the ALICE detector at the LHC. We compute the correlation function of $D$ mesons and light mesons using an off-shell $T$-matrix approach to access the two-meson wave function, and predict the correlation functions involving charged $D^+, D^{*+},D_s^+$ and $D_s^{*+}$ with $\pi^\pm$ and $K^\pm$. From the obtained results -- all of them accessible in $p+p$ collision experiments -- we point up the case of $D^+ \pi^-$, which is sensitive to the lower state of the two-pole $D_0^* (2300)$ system. The presence of such poles imprints a depletion on the correlation function, which could potentially be detected in experiments. While preliminary ALICE data do not show evidence of this effect, we suggest to look into the $D_s^+ K^-$ system to explore the higher pole of the $D_0^* (2300)$, as the depletion in the correlation function is more pronounced. Using heavy-quark spin symmetry we also propose exploring the effect of the two poles of the $D_1(2430)$ and predict similar structures in the correlation functions of the $D^{*+} \pi^-$ and $D_s^{*+} K^-$ pairs.
2107.02640
Daniel Milne
Valentin V. Khoze and Daniel L. Milne
Optical effects of domain walls
v4: Added discussion on effects caused by change in Bohr radius, matches version accepted for publication in Physics Letters B
null
10.1016/j.physletb.2022.137044
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Domain walls arise in theories where there is spontaneous symmetry breaking of a discrete symmetry such as $\mathbb{Z}_{N}$ and are a feature of many BSM models. In this work we consider the possibility of detecting domain walls through their optical effects and specify three different methods of coupling domain walls to the photon. We consider the effects of these couplings in the context of gravitational wave detectors, such as LIGO, and examine the sensitivity of these experiments to domain wall effects. In cases where gravitational wave detectors are not sensitive we examine our results in the context of axion experiments and show how effects of passing domain walls can be detected at interferometers searching for an axion signal.
[ { "created": "Tue, 6 Jul 2021 14:27:40 GMT", "version": "v1" }, { "created": "Wed, 7 Jul 2021 12:53:47 GMT", "version": "v2" }, { "created": "Mon, 26 Jul 2021 14:29:30 GMT", "version": "v3" }, { "created": "Thu, 28 Apr 2022 08:57:26 GMT", "version": "v4" } ]
2022-04-29
[ [ "Khoze", "Valentin V.", "" ], [ "Milne", "Daniel L.", "" ] ]
Domain walls arise in theories where there is spontaneous symmetry breaking of a discrete symmetry such as $\mathbb{Z}_{N}$ and are a feature of many BSM models. In this work we consider the possibility of detecting domain walls through their optical effects and specify three different methods of coupling domain walls to the photon. We consider the effects of these couplings in the context of gravitational wave detectors, such as LIGO, and examine the sensitivity of these experiments to domain wall effects. In cases where gravitational wave detectors are not sensitive we examine our results in the context of axion experiments and show how effects of passing domain walls can be detected at interferometers searching for an axion signal.
hep-ph/0105021
Eduardo Ponton
Eduardo Ponton, Erich Poppitz
Casimir Energy and Radius Stabilization in Five and Six Dimensional Orbifolds
36 pages, discussion on stabilization of the torus modular parameter added
JHEP 0106:019,2001
10.1088/1126-6708/2001/06/019
null
hep-ph hep-th
null
We compute the one-loop Casimir energy of gravity and matter fields, obeying various boundary conditions, in 5-dimensional S^1/Z_2 and 6-dimensional T^2/Z_k orbifolds. We discuss the role of the Casimir energy in possible radius stabilization mechanisms and show that the presence of massive as well as massless fields can lead to minima with zero cosmological constant. In the 5-d orbifold, we also consider the case where kinetic terms localized at the fixed points are not small. We take into account their contribution to the Casimir energy and show that localized kinetic terms can also provide a mechanism for radius stabilization. We apply our results to a recently proposed 5-dimensional supersymmetric model of electroweak symmetry breaking and show that the Casimir energy with the minimal matter content is repulsive. Stabilizing the radius with zero cosmological constant requires, in this context, adding positive bulk cosmological constant and negative brane-tension counterterms.
[ { "created": "Wed, 2 May 2001 16:39:47 GMT", "version": "v1" }, { "created": "Thu, 17 May 2001 15:32:08 GMT", "version": "v2" }, { "created": "Thu, 14 Jun 2001 18:15:44 GMT", "version": "v3" } ]
2010-05-28
[ [ "Ponton", "Eduardo", "" ], [ "Poppitz", "Erich", "" ] ]
We compute the one-loop Casimir energy of gravity and matter fields, obeying various boundary conditions, in 5-dimensional S^1/Z_2 and 6-dimensional T^2/Z_k orbifolds. We discuss the role of the Casimir energy in possible radius stabilization mechanisms and show that the presence of massive as well as massless fields can lead to minima with zero cosmological constant. In the 5-d orbifold, we also consider the case where kinetic terms localized at the fixed points are not small. We take into account their contribution to the Casimir energy and show that localized kinetic terms can also provide a mechanism for radius stabilization. We apply our results to a recently proposed 5-dimensional supersymmetric model of electroweak symmetry breaking and show that the Casimir energy with the minimal matter content is repulsive. Stabilizing the radius with zero cosmological constant requires, in this context, adding positive bulk cosmological constant and negative brane-tension counterterms.
2311.04695
Yasuhiro Yamaguchi
Tatsuya Asanuma, Yasuhiro Yamaguchi, Masayasu Harada
Analysis of $DD^*$ and $\bar{D}^{(*)}\Xi_{cc}^{(*)}$ molecule by one boson exchange model based on Heavy quark symmetry
10 pages, 9 figures, 5 tables
null
null
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
Numerous exotic hadrons with heavy quarks have been reported in the experiments. In such states, symmetries of heavy quarks are considered to play a significant role. In particular, the superflavor symmetry, or also called the heavy quark anti-diquark symmetry is one of the interesting symmetries, which links a quark $Q$ to an anti-diquark $\bar{Q}\bar{Q}$ having the same color representation as $Q$. In this paper, we study a $\bar{D}\Xi_{cc}$ molecular state as a superflavor partner of the doubly charm tetraquark $T_{cc}$ reported by LHCb recently. $T_{cc}$ locating slightly below the $DD^*$ threshold is a candidate of the hadronic molecule. Thus by replacing the singly charm meson $D^{(*)}$ with the doubly charm baryon $\Xi_{cc}^{(*)}$, superflavor symmetry predicts the existence of the $\bar{D}^{(*)}\Xi_{cc}^{(*)}$ bound state. We employ the one boson exchange model respecting with the heavy quark spin symmetry where the parameter is obtained to reproduce the $T_{cc}$ binding energy. We apply this model with superflavor symmetry to the $\bar{D}^{(*)}\Xi_{cc}^{(*)}$ molecule and predict a bound state with $I(J^P) = 0(\frac{1}{2}^-)$. If the pentaquark state corresponding to $\bar{D}^{(*)} \Xi_{cc}^{(*)}$ molecular state is observed in future experiments as predicted in this work, it is more likely that $T_{cc}$ is a $DD^*$ molecular state.
[ { "created": "Wed, 8 Nov 2023 14:06:03 GMT", "version": "v1" } ]
2023-11-09
[ [ "Asanuma", "Tatsuya", "" ], [ "Yamaguchi", "Yasuhiro", "" ], [ "Harada", "Masayasu", "" ] ]
Numerous exotic hadrons with heavy quarks have been reported in the experiments. In such states, symmetries of heavy quarks are considered to play a significant role. In particular, the superflavor symmetry, or also called the heavy quark anti-diquark symmetry is one of the interesting symmetries, which links a quark $Q$ to an anti-diquark $\bar{Q}\bar{Q}$ having the same color representation as $Q$. In this paper, we study a $\bar{D}\Xi_{cc}$ molecular state as a superflavor partner of the doubly charm tetraquark $T_{cc}$ reported by LHCb recently. $T_{cc}$ locating slightly below the $DD^*$ threshold is a candidate of the hadronic molecule. Thus by replacing the singly charm meson $D^{(*)}$ with the doubly charm baryon $\Xi_{cc}^{(*)}$, superflavor symmetry predicts the existence of the $\bar{D}^{(*)}\Xi_{cc}^{(*)}$ bound state. We employ the one boson exchange model respecting with the heavy quark spin symmetry where the parameter is obtained to reproduce the $T_{cc}$ binding energy. We apply this model with superflavor symmetry to the $\bar{D}^{(*)}\Xi_{cc}^{(*)}$ molecule and predict a bound state with $I(J^P) = 0(\frac{1}{2}^-)$. If the pentaquark state corresponding to $\bar{D}^{(*)} \Xi_{cc}^{(*)}$ molecular state is observed in future experiments as predicted in this work, it is more likely that $T_{cc}$ is a $DD^*$ molecular state.
hep-ph/9912327
Davison E. Soper
Parvez Anandam and Davison E. Soper
Factorization scheme dependence of the NLO inclusive jet cross section
8 pages including 3 figures
Phys.Rev. D61 (2000) 094003
10.1103/PhysRevD.61.094003
null
hep-ph
null
We study the factorization scheme dependence of the next-to-leading order inclusive one jet cross section d sigma/dE_T. The scheme is varied parametrically along the direction that transforms the MSbar scheme to the DIS scheme: we introduce a parameter lambda such that lambda = 0 is MSbar and lambda = 1 is DIS. The factorization scale mu is also varied. We observe a change of +/- 9% in the cross section for E_T = 50 GeV when mu and lambda are varied in the range -2 < lambda < 2, E_T/8 < mu < 2 E_T. This grows to +/- 32% for E_T = 400 GeV.
[ { "created": "Tue, 14 Dec 1999 00:55:17 GMT", "version": "v1" } ]
2009-10-31
[ [ "Anandam", "Parvez", "" ], [ "Soper", "Davison E.", "" ] ]
We study the factorization scheme dependence of the next-to-leading order inclusive one jet cross section d sigma/dE_T. The scheme is varied parametrically along the direction that transforms the MSbar scheme to the DIS scheme: we introduce a parameter lambda such that lambda = 0 is MSbar and lambda = 1 is DIS. The factorization scale mu is also varied. We observe a change of +/- 9% in the cross section for E_T = 50 GeV when mu and lambda are varied in the range -2 < lambda < 2, E_T/8 < mu < 2 E_T. This grows to +/- 32% for E_T = 400 GeV.
1603.04970
Raghunath Sahoo
Trambak Bhattacharyya, Arvind Khuntia, Pragati Sahoo, Prakhar Garg, Pooja Pareek, Raghunath Sahoo, Jean Cleymans
The q-Statistics and QCD Thermodynamics at LHC
4 pages, 4 figures. To be published in the Proceedings of the 11th Workshop on Particle Correlations and Femtoscopy (WPCF 2015), 03-07 Nov 2015, Warsaw, Poland
null
null
null
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform a Taylor series expansion of Tsallis distribution by assuming the Tsallis parameter $q$ close to 1. The $q$ value shows the deviation of a system from a thermalised Boltzmann distribution. By taking up to first order in $(q-1)$, we derive an analytical result for Tsallis distribution including radial flow. Further, in the present work, we also study the speed of sound ($c_s$) as a function of temperature using the non-extensive Tsallis statistics for different $q$ values and for different mass cut-offs.
[ { "created": "Wed, 16 Mar 2016 05:49:48 GMT", "version": "v1" } ]
2016-03-17
[ [ "Bhattacharyya", "Trambak", "" ], [ "Khuntia", "Arvind", "" ], [ "Sahoo", "Pragati", "" ], [ "Garg", "Prakhar", "" ], [ "Pareek", "Pooja", "" ], [ "Sahoo", "Raghunath", "" ], [ "Cleymans", "Jean", "" ] ]
We perform a Taylor series expansion of Tsallis distribution by assuming the Tsallis parameter $q$ close to 1. The $q$ value shows the deviation of a system from a thermalised Boltzmann distribution. By taking up to first order in $(q-1)$, we derive an analytical result for Tsallis distribution including radial flow. Further, in the present work, we also study the speed of sound ($c_s$) as a function of temperature using the non-extensive Tsallis statistics for different $q$ values and for different mass cut-offs.
hep-ph/0208276
Kenji Kadota
Patrick B. Greene, Kenji Kadota, Hitoshi Murayama
Supergravity Inflation Free from Harmful Relics
10 pages, revtex, 1 eps figure, references added, conclusion section expanded
Phys.Rev.D68:043502,2003
10.1103/PhysRevD.68.043502
UCB-PTH-02/37,LBNL-51431,FERMILAB-Pub-02/300
hep-ph
null
We present a realistic supergravity inflation model which is free from the overproduction of potentially dangerous relics in cosmology, namely moduli and gravitinos which can lead to the inconsistencies with the predictions of baryon asymmetry and nucleosynthesis. The radiative correction turns out to play a crucial role in our analysis which raises the mass of supersymmetry breaking field to intermediate scale. We pay a particular attention to the non-thermal production of gravitinos using the non-minimal Kahler potential we obtained from loop correction. This non-thermal gravitino production however is diminished because of the relatively small scale of inflaton mass and small amplitudes of hidden sector fields.
[ { "created": "Fri, 30 Aug 2002 17:08:04 GMT", "version": "v1" }, { "created": "Mon, 17 Mar 2003 20:56:15 GMT", "version": "v2" } ]
2009-09-29
[ [ "Greene", "Patrick B.", "" ], [ "Kadota", "Kenji", "" ], [ "Murayama", "Hitoshi", "" ] ]
We present a realistic supergravity inflation model which is free from the overproduction of potentially dangerous relics in cosmology, namely moduli and gravitinos which can lead to the inconsistencies with the predictions of baryon asymmetry and nucleosynthesis. The radiative correction turns out to play a crucial role in our analysis which raises the mass of supersymmetry breaking field to intermediate scale. We pay a particular attention to the non-thermal production of gravitinos using the non-minimal Kahler potential we obtained from loop correction. This non-thermal gravitino production however is diminished because of the relatively small scale of inflaton mass and small amplitudes of hidden sector fields.
1805.02685
Diego Aristizabal
D. Aristizabal Sierra, Chee Sheng Fong
The EDGES signal: An imprint from the mirror world?
8 pages, 2 figures
null
10.1016/j.physletb.2018.07.047
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent results from the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) show an anomalous spectral feature at redshifts $z\sim 15-20$ in its 21-cm absorption signal. This deviation from cosmological predictions can be understood as a consequence of physics that either lower the hydrogen spin temperature or increases the radiation temperature through the injection of soft photons in the bath. In the latter case, standard model neutrino decays $\nu_i \to \nu_j\,\gamma$ induced by effective magnetic and electric transition moments ($\mu_\text{eff}$) are precluded by the tight astrophysical constraints on $\mu_\text{eff}$. We show that if mirror neutrinos are present in the bath at early times, an analogous mechanism in the mirror sector can lead to a population of mirror photons that are then "processed" into visible photons through resonant conversion, thus accounting for the EDGES signal. We point out that the mechanism can work for mirror neutrinos which are either heavier than or degenerate with the standard model (SM) neutrinos, a scenario naturally realized in mirror twin Higgs models.
[ { "created": "Mon, 7 May 2018 18:32:14 GMT", "version": "v1" } ]
2018-08-01
[ [ "Sierra", "D. Aristizabal", "" ], [ "Fong", "Chee Sheng", "" ] ]
Recent results from the Experiment to Detect the Global Epoch of Reionization Signature (EDGES) show an anomalous spectral feature at redshifts $z\sim 15-20$ in its 21-cm absorption signal. This deviation from cosmological predictions can be understood as a consequence of physics that either lower the hydrogen spin temperature or increases the radiation temperature through the injection of soft photons in the bath. In the latter case, standard model neutrino decays $\nu_i \to \nu_j\,\gamma$ induced by effective magnetic and electric transition moments ($\mu_\text{eff}$) are precluded by the tight astrophysical constraints on $\mu_\text{eff}$. We show that if mirror neutrinos are present in the bath at early times, an analogous mechanism in the mirror sector can lead to a population of mirror photons that are then "processed" into visible photons through resonant conversion, thus accounting for the EDGES signal. We point out that the mechanism can work for mirror neutrinos which are either heavier than or degenerate with the standard model (SM) neutrinos, a scenario naturally realized in mirror twin Higgs models.
2310.09870
Matteo Becchetti
Matteo Becchetti
Two-loop master integrals for a planar topology contributing to $pp \rightarrow t\bar{t}j$
Proceedings for Radcor 2023, 8 pages, 1 figure
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on recent progress for the QCD corrections to top quark pair plus jet production. In particular, we discuss a recent computation for the two-loop master integrals associated to a two-loop five-point pentagon-box integral configuration with one internal massive propagator, that contributes to top quark pair production in association with a jet in the QCD planar limit.
[ { "created": "Sun, 15 Oct 2023 15:56:42 GMT", "version": "v1" } ]
2023-10-17
[ [ "Becchetti", "Matteo", "" ] ]
We report on recent progress for the QCD corrections to top quark pair plus jet production. In particular, we discuss a recent computation for the two-loop master integrals associated to a two-loop five-point pentagon-box integral configuration with one internal massive propagator, that contributes to top quark pair production in association with a jet in the QCD planar limit.
hep-ph/0510059
Mustapha Mekhfi
M.Mekhfi
Tensor charge and anomalous magnetic moment correlation
26 pages, PDF format only
Phys.Rev.D72:114014,2005
10.1103/PhysRevD.72.114014
null
hep-ph
null
We propose a generalization of the upgraded Karl- Sehgal formula which relates baryon magnetic moments to the spin structure of constituent quarks, by adding anomalous magnetic moments of quarks. We first argue that relativistic nature of quarks inside baryons requires introduction of two kinds of magnetisms, one axial and the other tensoriel. The first one is associated with integrated quark helicity distributions (standard) and the second with integrated transversity distributions . The weight of each contribution is controlled by the combination of two parameters, xi the ratio of the quark mass to the average kinetic energy Ei and ai the quark anomalous magnetic moment. The quark anomalous magnetic moment is correlated to transversity and both are necessary ingredients in describing relativistic quarks. The proposed formula, then when confronted with baryon magnetic moments data with reasonable inputs, yields beside quark magnetic densities, anomalous magnetic moments enough large to not be ignored.
[ { "created": "Wed, 5 Oct 2005 13:56:29 GMT", "version": "v1" } ]
2011-09-09
[ [ "Mekhfi", "M.", "" ] ]
We propose a generalization of the upgraded Karl- Sehgal formula which relates baryon magnetic moments to the spin structure of constituent quarks, by adding anomalous magnetic moments of quarks. We first argue that relativistic nature of quarks inside baryons requires introduction of two kinds of magnetisms, one axial and the other tensoriel. The first one is associated with integrated quark helicity distributions (standard) and the second with integrated transversity distributions . The weight of each contribution is controlled by the combination of two parameters, xi the ratio of the quark mass to the average kinetic energy Ei and ai the quark anomalous magnetic moment. The quark anomalous magnetic moment is correlated to transversity and both are necessary ingredients in describing relativistic quarks. The proposed formula, then when confronted with baryon magnetic moments data with reasonable inputs, yields beside quark magnetic densities, anomalous magnetic moments enough large to not be ignored.
hep-ph/9807307
Utpal Sarkar
Ernest Ma and Utpal Sarkar
Gauged $B - 3 L_\tau$ and Baryogenesis
16 pages including two postscript figures
Phys.Lett. B439 (1998) 95-102
10.1016/S0370-2693(98)01019-3
DESY 98-082 ; UCRHEP-T230
hep-ph
null
It has recently been shown that by extending the minimal standard model to include a right-handed partner to $\nu_\tau$, it is possible to gauge the $B - 3 L_\tau$ quantum number consistently. If we add two scalar triplets, one trivial ($\xi_1$) and one nontrivial ($\xi_2$) under $B - 3 L_\tau$, it is possible also to have desirable neutrino masses and mixing for neutrino oscillations. At the same time, a lepton asymmetry can be generated in the early universe through the novel mechanism of the decay of the heavier $\xi_1$ into the lighter $\xi_2$ plus a neutral singlet ($\zeta^0$). This lepton asymmetry then gets converted into a baryon asymmetry at the electroweak phase transition.
[ { "created": "Thu, 9 Jul 1998 14:01:13 GMT", "version": "v1" } ]
2009-10-31
[ [ "Ma", "Ernest", "" ], [ "Sarkar", "Utpal", "" ] ]
It has recently been shown that by extending the minimal standard model to include a right-handed partner to $\nu_\tau$, it is possible to gauge the $B - 3 L_\tau$ quantum number consistently. If we add two scalar triplets, one trivial ($\xi_1$) and one nontrivial ($\xi_2$) under $B - 3 L_\tau$, it is possible also to have desirable neutrino masses and mixing for neutrino oscillations. At the same time, a lepton asymmetry can be generated in the early universe through the novel mechanism of the decay of the heavier $\xi_1$ into the lighter $\xi_2$ plus a neutral singlet ($\zeta^0$). This lepton asymmetry then gets converted into a baryon asymmetry at the electroweak phase transition.
1008.0540
P\'ia Zurita
M. Stratmann, R. Sassot and P. Zurita
Inclusive Hadron Production in the CERN-LHC Era
14 pages, 13 fugures
Phys.Rev.D82:074011,2010
10.1103/PhysRevD.82.074011
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a detailed phenomenological analysis of single-inclusive hadron production at the CERN-LHC in both proton-proton and proton-lead collisions. First data from the LHC experiments on charged hadron spectra are compared to next-to-leading order QCD expectations, and predictions are made for identified pion, kaon, and proton distributions differential in transverse momentum and rapidity for LHC energies from 900 GeV to 14 TeV. The results are obtained with the latest sets of vacuum fragmentation functions based on global QCD analyses, and recently proposed medium modified fragmentation functions are used to model hadronization in proton-lead collisions assuming standard QCD factorization. Besides estimating theoretical ambiguities due to the choice of factorization and renormalization scales and parton densities, we carefully assess uncertainties due to our present knowledge of parton-to-hadron fragmentation functions with the Lagrange multiplier technique. It is outlined to what extent future LHC data will contribute to further our quantitative understanding of hadronization processes.
[ { "created": "Tue, 3 Aug 2010 13:06:36 GMT", "version": "v1" } ]
2014-11-21
[ [ "Stratmann", "M.", "" ], [ "Sassot", "R.", "" ], [ "Zurita", "P.", "" ] ]
We present a detailed phenomenological analysis of single-inclusive hadron production at the CERN-LHC in both proton-proton and proton-lead collisions. First data from the LHC experiments on charged hadron spectra are compared to next-to-leading order QCD expectations, and predictions are made for identified pion, kaon, and proton distributions differential in transverse momentum and rapidity for LHC energies from 900 GeV to 14 TeV. The results are obtained with the latest sets of vacuum fragmentation functions based on global QCD analyses, and recently proposed medium modified fragmentation functions are used to model hadronization in proton-lead collisions assuming standard QCD factorization. Besides estimating theoretical ambiguities due to the choice of factorization and renormalization scales and parton densities, we carefully assess uncertainties due to our present knowledge of parton-to-hadron fragmentation functions with the Lagrange multiplier technique. It is outlined to what extent future LHC data will contribute to further our quantitative understanding of hadronization processes.
hep-ph/0103155
Guido Montagna
G. Montagna, M. Moretti, O. Nicrosini, M. Osmo, F. Piccinini
Radiative four-fermion processes at LEP2
LaTeX, 14 pages, 6 tables, 13 figures. Numerical results added, version to appear in Eur. Phys. J. C
Eur.Phys.J.C21:291-301,2001
10.1007/s100520100736
FNT/T-2000/12
hep-ph hep-ex
null
The production of four fermions plus a visible photon in electron-positron collisions is analyzed, with particular emphasis on the LEP2 energy range. The study is based on the calculation of exact matrix elements, including the effect of fermion masses. In the light of the present measurements performed at LEP, triple and quartic anomalous gauge couplings are taken into account. Due to the presence of a visible photon in the final state, particular attention is paid to the treatment of higher-order QED corrections. Explicit results for integrated cross sections and differential distributions are shown and commented. The features of the Monte Carlo program WRAP, used to perform the calculation and available for experimental analysis, are described.
[ { "created": "Wed, 14 Mar 2001 12:54:50 GMT", "version": "v1" }, { "created": "Fri, 29 Jun 2001 09:36:14 GMT", "version": "v2" } ]
2011-09-13
[ [ "Montagna", "G.", "" ], [ "Moretti", "M.", "" ], [ "Nicrosini", "O.", "" ], [ "Osmo", "M.", "" ], [ "Piccinini", "F.", "" ] ]
The production of four fermions plus a visible photon in electron-positron collisions is analyzed, with particular emphasis on the LEP2 energy range. The study is based on the calculation of exact matrix elements, including the effect of fermion masses. In the light of the present measurements performed at LEP, triple and quartic anomalous gauge couplings are taken into account. Due to the presence of a visible photon in the final state, particular attention is paid to the treatment of higher-order QED corrections. Explicit results for integrated cross sections and differential distributions are shown and commented. The features of the Monte Carlo program WRAP, used to perform the calculation and available for experimental analysis, are described.
hep-ph/0405151
Saime Kerman
Ayse Kucukarslan, Saime Solmaz
Different Contributions in omega pi0etagamma and rho pi0etagamma decays
13 pages, 4 figures, 3 tables
Phys.Rev. D70 (2004) 053004
10.1103/PhysRevD.70.053004
null
hep-ph
null
We examine the radiative omega pi0etagamma and rho pi0etagamma decays in a phenomenological framework. We consider the VMD mechanism, chiral loops, intermediate a0-meson and rho&#8722;omega mixing. We find the values of the decay width coming from the different amplitudes and compare the results with other studies. We observe that a0-meson intermediate state is very important in the case of the rho pi0etagamma decay and small in the other case for which VMD contribution is dominant.
[ { "created": "Mon, 17 May 2004 09:20:15 GMT", "version": "v1" }, { "created": "Fri, 21 May 2004 08:23:53 GMT", "version": "v2" } ]
2009-11-10
[ [ "Kucukarslan", "Ayse", "" ], [ "Solmaz", "Saime", "" ] ]
We examine the radiative omega pi0etagamma and rho pi0etagamma decays in a phenomenological framework. We consider the VMD mechanism, chiral loops, intermediate a0-meson and rho&#8722;omega mixing. We find the values of the decay width coming from the different amplitudes and compare the results with other studies. We observe that a0-meson intermediate state is very important in the case of the rho pi0etagamma decay and small in the other case for which VMD contribution is dominant.
hep-ph/0202031
Arttu Rajantie
E.J. Copeland, S. Pascoli and A. Rajantie
Dynamics of tachyonic preheating after hybrid inflation
12 pages, 10 figures, REVTeX. Minor changes, some references added. To appear in PRD
Phys.Rev. D65 (2002) 103517
10.1103/PhysRevD.65.103517
DAMTP-2002-1, SUSX-TH-02-002, SISSA/2/2002/EP
hep-ph astro-ph hep-th
null
We study the instability of a scalar field at the end of hybrid inflation, using both analytical techniques and numerical simulations. We improve previous studies by taking the inflaton field fully into account, and show that the range of unstable modes depends sensitively on the velocity of the inflaton field, and thereby on the Hubble rate, at the end of inflation. If topological defects are formed, their number density is determined by the shortest unstable wavelength. Finally, we show that the oscillations of the inflaton field amplify the inhomogeneities in the energy density, leading to local symmetry restoration and faster thermalization. We believe this explains why tachyonic preheating is so effective in transferring energy away from the inflaton zero mode.
[ { "created": "Tue, 5 Feb 2002 17:00:55 GMT", "version": "v1" }, { "created": "Wed, 20 Mar 2002 12:48:31 GMT", "version": "v2" } ]
2009-11-07
[ [ "Copeland", "E. J.", "" ], [ "Pascoli", "S.", "" ], [ "Rajantie", "A.", "" ] ]
We study the instability of a scalar field at the end of hybrid inflation, using both analytical techniques and numerical simulations. We improve previous studies by taking the inflaton field fully into account, and show that the range of unstable modes depends sensitively on the velocity of the inflaton field, and thereby on the Hubble rate, at the end of inflation. If topological defects are formed, their number density is determined by the shortest unstable wavelength. Finally, we show that the oscillations of the inflaton field amplify the inhomogeneities in the energy density, leading to local symmetry restoration and faster thermalization. We believe this explains why tachyonic preheating is so effective in transferring energy away from the inflaton zero mode.
hep-ph/0003100
Johannes Bluemlein
Johannes Bl\"umlein
Analytic Continuation of Mellin Transforms up to two-loop Order
31 pages LATEX, 1 style file
Comput.Phys.Commun. 133 (2000) 76-104
10.1016/S0010-4655(00)00156-9
DESY 98-149
hep-ph hep-th
null
The analytic continuation of the Mellin transforms to complex values of N for the basic functions $g_i(x)$ of the momentum fraction x emerging in the quantities of massless QED and QCD up to two-loop order, as the unpolarized and polarized splitting functions, coefficient functions, and hard scattering cross sections for space- and time-like momentum transfer are evaluated. These Mellin transforms provide the analytic continuations of all finite harmonic sums up to the level of the threefold sums of transcendentality four, where the basis-set ${g_i(x)}$ consists of products of {\sc Nielsen}-integrals up to transcendentality four. The computer code {\tt ANCONT} is provided.
[ { "created": "Fri, 10 Mar 2000 16:01:54 GMT", "version": "v1" } ]
2009-10-31
[ [ "Blümlein", "Johannes", "" ] ]
The analytic continuation of the Mellin transforms to complex values of N for the basic functions $g_i(x)$ of the momentum fraction x emerging in the quantities of massless QED and QCD up to two-loop order, as the unpolarized and polarized splitting functions, coefficient functions, and hard scattering cross sections for space- and time-like momentum transfer are evaluated. These Mellin transforms provide the analytic continuations of all finite harmonic sums up to the level of the threefold sums of transcendentality four, where the basis-set ${g_i(x)}$ consists of products of {\sc Nielsen}-integrals up to transcendentality four. The computer code {\tt ANCONT} is provided.
1407.4311
Jihn E. Kim
S. M. Barr and Jihn E. Kim
New confining force solution of QCD axion domain wall problem
LaTeX file of 5 pages
Phys. Rev. Lett. 113, 241301 (2014)
10.1103/PhysRevLett.113.241301
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The serious cosmological problems created by the axion-string/axion-domain-wall system in standard axion models are alleviated by positing the existence of a new confining force. The instantons of this force can generate an axion potential that erases the axion strings long before QCD effects become important, thus preventing QCD-generated axion walls from ever appearing. Axion walls generated by the new confining force would decay so early as not to contribute significantly to the energy in axion dark matter.
[ { "created": "Wed, 16 Jul 2014 13:55:27 GMT", "version": "v1" }, { "created": "Thu, 13 Nov 2014 12:41:06 GMT", "version": "v2" } ]
2014-12-10
[ [ "Barr", "S. M.", "" ], [ "Kim", "Jihn E.", "" ] ]
The serious cosmological problems created by the axion-string/axion-domain-wall system in standard axion models are alleviated by positing the existence of a new confining force. The instantons of this force can generate an axion potential that erases the axion strings long before QCD effects become important, thus preventing QCD-generated axion walls from ever appearing. Axion walls generated by the new confining force would decay so early as not to contribute significantly to the energy in axion dark matter.
hep-ph/9907341
Vincenzo Cirigliano
V. Cirigliano, J. Donoghue and E. Golowich
Electromagnetic Corrections to K -> pi pi I: Chiral Perturbation Theory
20 Pages, LaTeX, 5 figures, 1 table. Revised version. Minor numerical changes in results
Phys.Rev.D61:093001,2000; Erratum-ibid.D63:059903,2001
10.1103/PhysRevD.61.093001 10.1103/PhysRevD.63.059903
null
hep-ph
null
An analysis of electromagnetic corrections to the (dominant) octet K -> pi pi hamiltonian using chiral perturbation theory is carried out. Relative shifts in amplitudes at the several per cent level are found.
[ { "created": "Tue, 13 Jul 1999 19:17:49 GMT", "version": "v1" }, { "created": "Thu, 23 Sep 1999 19:19:12 GMT", "version": "v2" }, { "created": "Mon, 29 Nov 1999 15:51:53 GMT", "version": "v3" } ]
2014-11-17
[ [ "Cirigliano", "V.", "" ], [ "Donoghue", "J.", "" ], [ "Golowich", "E.", "" ] ]
An analysis of electromagnetic corrections to the (dominant) octet K -> pi pi hamiltonian using chiral perturbation theory is carried out. Relative shifts in amplitudes at the several per cent level are found.
hep-ph/0406086
Nikolai Uraltsev
Nikolai Uraltsev
QCD in beauty decays: successes and puzzles
7 pages, LaTeX, four figures; uses moriondmod.sty; XXXIXth Rencontres de Moriond: QCD and Hadronic Interactions, March 28 - April 4, 2004, La Thuile, Italy
null
null
Bicocca-FT-04-6, UND-HEP-04-BIG04
hep-ph
null
The status of the heavy quark expansion for inclusive B decays is briefly reviewed from the perspective of confronting theory with data and of extracting the heavy quark parameters. A good agreement between properly applied theory and new precision data is observed. Some recent applications to the exclusive heavy flavor transitions are addressed. I recall the `1/2 > 3/2' paradox for the transitions into the charm P-wave states.
[ { "created": "Tue, 8 Jun 2004 16:38:28 GMT", "version": "v1" } ]
2007-05-23
[ [ "Uraltsev", "Nikolai", "" ] ]
The status of the heavy quark expansion for inclusive B decays is briefly reviewed from the perspective of confronting theory with data and of extracting the heavy quark parameters. A good agreement between properly applied theory and new precision data is observed. Some recent applications to the exclusive heavy flavor transitions are addressed. I recall the `1/2 > 3/2' paradox for the transitions into the charm P-wave states.
2004.14831
Stella Schindler
Markus A. Ebert, Stella T. Schindler, Iain W. Stewart, and Yong Zhao
One-loop Matching for Spin-Dependent Quasi-TMDs
24 pages, 4 figures
JHEP 09 (2020) 099
10.1007/JHEP09(2020)099
MIT-CTP 5200
hep-ph hep-lat nucl-th
http://creativecommons.org/licenses/by/4.0/
Transverse momentum dependent parton distribution functions (TMDPDFs) provide a unique probe of the three-dimensional spin structure of hadrons. We construct spin-dependent quasi-TMDPDFs that are amenable to lattice QCD calculations and that can be used to determine spin-dependent TMDPDFs. We calculate the short-distance coefficients connecting spin-dependent TMDPDFs and quasi-TMDPDFs at one-loop order. We find that the helicity and transversity distributions have the same coefficient as the unpolarized TMDPDF. We also argue that the same is true for pretzelosity and that this spin universality of the matching will hold to all orders in $\alpha_s$. Thus, it is possible to calculate ratios of these distributions as a function of longitudinal momentum and transverse position utilizing simpler Wilson line paths than have previously been considered.
[ { "created": "Thu, 30 Apr 2020 14:36:26 GMT", "version": "v1" } ]
2020-10-02
[ [ "Ebert", "Markus A.", "" ], [ "Schindler", "Stella T.", "" ], [ "Stewart", "Iain W.", "" ], [ "Zhao", "Yong", "" ] ]
Transverse momentum dependent parton distribution functions (TMDPDFs) provide a unique probe of the three-dimensional spin structure of hadrons. We construct spin-dependent quasi-TMDPDFs that are amenable to lattice QCD calculations and that can be used to determine spin-dependent TMDPDFs. We calculate the short-distance coefficients connecting spin-dependent TMDPDFs and quasi-TMDPDFs at one-loop order. We find that the helicity and transversity distributions have the same coefficient as the unpolarized TMDPDF. We also argue that the same is true for pretzelosity and that this spin universality of the matching will hold to all orders in $\alpha_s$. Thus, it is possible to calculate ratios of these distributions as a function of longitudinal momentum and transverse position utilizing simpler Wilson line paths than have previously been considered.
1409.4900
Lei Guo
Chen Chong, Ma Wen-Gan, Zhang Ren-You, Zhang Yu, Chen Liang-Wen, and Guo Lei
Electroweak radiative corrections to $W^+W^-\gamma$ production at the ILC
23 pages, 11 figures
Eur. Phys. J. C 74:3166 (2014)
10.1140/epjc/s10052-014-3166-y
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We provide and discuss the precision predictions for the $W^+W^-\gamma$ production at the ILC including the full electroweak (EW) one-loop corrections and high order initial state radiation (ISR) contributions in the Standard Model. The dependence of the leading order (LO) and EW corrected cross sections on the colliding energy is investigated. We find that the EW correction suppresses the LO cross section significantly, and the ISR effect beyond ${\cal O}(\alpha)$ is important near the threshold, but is negligible in the high energy region. We provide the LO and EW corrected distributions of the transverse momenta and rapidities of final $W^-$-boson and photon as well as the $W$-pair invariant mass. From the various kinematic distributions, we find that EW correction strongly depends on the final state phase space. We investigate the leptonic decays of the final W-boson pair by adopting the narrow width approximation (NWA), and find that the final produced photon and leptons can be well separated from each other.
[ { "created": "Wed, 17 Sep 2014 08:35:47 GMT", "version": "v1" } ]
2014-12-30
[ [ "Chong", "Chen", "" ], [ "Wen-Gan", "Ma", "" ], [ "Ren-You", "Zhang", "" ], [ "Yu", "Zhang", "" ], [ "Liang-Wen", "Chen", "" ], [ "Lei", "Guo", "" ] ]
We provide and discuss the precision predictions for the $W^+W^-\gamma$ production at the ILC including the full electroweak (EW) one-loop corrections and high order initial state radiation (ISR) contributions in the Standard Model. The dependence of the leading order (LO) and EW corrected cross sections on the colliding energy is investigated. We find that the EW correction suppresses the LO cross section significantly, and the ISR effect beyond ${\cal O}(\alpha)$ is important near the threshold, but is negligible in the high energy region. We provide the LO and EW corrected distributions of the transverse momenta and rapidities of final $W^-$-boson and photon as well as the $W$-pair invariant mass. From the various kinematic distributions, we find that EW correction strongly depends on the final state phase space. We investigate the leptonic decays of the final W-boson pair by adopting the narrow width approximation (NWA), and find that the final produced photon and leptons can be well separated from each other.