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1708.05169
Shigehiro Yasui
Tetsuo Hyodo, Yan-Rui Liu, Makoto Oka, Shigehiro Yasui
Spectroscopy and production of doubly charmed tetraquarks
38 pages, 7 figures
null
null
YITP-17-88
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the production of the exotic doubly-charmed tetraquark mesons ${\rm T}_{{\rm c}{\rm c}}({\rm c}{\rm c}\bar{\rm u}\bar{\rm d})$ from electron-positron collisions. ${\rm T}_{{\rm c}{\rm c}}({\rm c}{\rm c}\bar{\rm u}\bar{\rm d})$ is a compact exotic hadron whose binding energy is provided by the diquark correlations. We evaluate the production cross section in the electron-positron collisions using the nonrelativistic QCD framework, and investigate the difference of the production cross section for different color configurations in two charm quarks (antitriplet and sextet), where the mixing of different configurations is suppressed in the heavy quark limit. The total cross section is estimated by modeling the nonperturbative fragmentation process of the charm quark pair into the tetraquark by the wavefunction of the tetraquark and the probability of picking up the light quarks. We find that the internal color configurations are distinguishable by the qualitative features of the differential cross sections which are independent of the nonperturbative matrix elements.
[ { "created": "Thu, 17 Aug 2017 08:40:21 GMT", "version": "v1" } ]
2017-08-21
[ [ "Hyodo", "Tetsuo", "" ], [ "Liu", "Yan-Rui", "" ], [ "Oka", "Makoto", "" ], [ "Yasui", "Shigehiro", "" ] ]
We discuss the production of the exotic doubly-charmed tetraquark mesons ${\rm T}_{{\rm c}{\rm c}}({\rm c}{\rm c}\bar{\rm u}\bar{\rm d})$ from electron-positron collisions. ${\rm T}_{{\rm c}{\rm c}}({\rm c}{\rm c}\bar{\rm u}\bar{\rm d})$ is a compact exotic hadron whose binding energy is provided by the diquark correlations. We evaluate the production cross section in the electron-positron collisions using the nonrelativistic QCD framework, and investigate the difference of the production cross section for different color configurations in two charm quarks (antitriplet and sextet), where the mixing of different configurations is suppressed in the heavy quark limit. The total cross section is estimated by modeling the nonperturbative fragmentation process of the charm quark pair into the tetraquark by the wavefunction of the tetraquark and the probability of picking up the light quarks. We find that the internal color configurations are distinguishable by the qualitative features of the differential cross sections which are independent of the nonperturbative matrix elements.
hep-ph/0011148
Uma Mahanta
Uma Mahanta
Quantum effects of compactified AdS_5 geometry on the higgs potential
Plain Tex, no figures, 10 pages
null
null
null
hep-ph
null
In this paper we determine the one loop radiative correction to the higgs potential due to quantum fluctuations about the background metric of Randall-Sundrum model. We then examine the effects of the one loop effective potential on the stability of the classical vacuum paying particular attention to the tadpole terms which could dominate over the classical potential for small field configurations. We find that although the one loop potential due to scale fluctuations could develop a tadpole term in certain regions of the parameter space, it is positive for either sign of H. The quadratic and quartic terms in the radiative correction are too small to cause any instability to the classical vacuum for field configurations that do not violate the limits of ordinary perturbation theory.
[ { "created": "Fri, 10 Nov 2000 11:34:06 GMT", "version": "v1" } ]
2007-05-23
[ [ "Mahanta", "Uma", "" ] ]
In this paper we determine the one loop radiative correction to the higgs potential due to quantum fluctuations about the background metric of Randall-Sundrum model. We then examine the effects of the one loop effective potential on the stability of the classical vacuum paying particular attention to the tadpole terms which could dominate over the classical potential for small field configurations. We find that although the one loop potential due to scale fluctuations could develop a tadpole term in certain regions of the parameter space, it is positive for either sign of H. The quadratic and quartic terms in the radiative correction are too small to cause any instability to the classical vacuum for field configurations that do not violate the limits of ordinary perturbation theory.
hep-ph/9605219
Dalibor Kekez
Dalibor Kekez (Rudjer Boskovic Institute, Zagreb, Croatia) and Dubravko Klabucar (Zagreb University, Zagreb, Croatia)
Two-photon processes of pseudoscalar mesons in a Bethe-Salpeter approach
RevTeX style, 15 pages, 1 PS figures, uses epsf.sty, minor revisions of the text, small additions to the table and to one figure, comments on new references
Phys.Lett. B387 (1996) 14-20
10.1016/0370-2693(96)00990-2
null
hep-ph
null
We evaluate the $\pi^0\gamma^* \to \gamma$ transition form factor and $\gamma\gamma$ decay widths for $\pi^0, \eta_c$ and $\eta_b$ treated as $q\bar{q}$ bound states in the Bethe-Salpeter formalism, incorporating the dynamical chiral symmetry breaking and the Goldstone nature of the pion. In the chiral limit, the Abelian axial anomaly is incorporated analytically in our coupled Schwinger-Dyson and Bethe-Salpeter approach, which is also capable of quantitatively describing systems of heavy quarks, concretely $\eta_c$ and possibly $\eta_b$.
[ { "created": "Fri, 3 May 1996 13:37:11 GMT", "version": "v1" }, { "created": "Fri, 11 Oct 1996 15:55:22 GMT", "version": "v2" } ]
2009-10-28
[ [ "Kekez", "Dalibor", "", "Rudjer Boskovic Institute, Zagreb, Croatia" ], [ "Klabucar", "Dubravko", "", "Zagreb University, Zagreb, Croatia" ] ]
We evaluate the $\pi^0\gamma^* \to \gamma$ transition form factor and $\gamma\gamma$ decay widths for $\pi^0, \eta_c$ and $\eta_b$ treated as $q\bar{q}$ bound states in the Bethe-Salpeter formalism, incorporating the dynamical chiral symmetry breaking and the Goldstone nature of the pion. In the chiral limit, the Abelian axial anomaly is incorporated analytically in our coupled Schwinger-Dyson and Bethe-Salpeter approach, which is also capable of quantitatively describing systems of heavy quarks, concretely $\eta_c$ and possibly $\eta_b$.
0707.0419
Johan Bijnens
Johan Bijnens
Radiative and semileptonic decays in Chiral Perturbation Theory
5 pages, presented at Kaon International Conference (KAON07), May 21-25, 2007, Laboratori Nazionali di Frascati dell'INFN, Frascati, Italy
PoSKAON:027,2008
null
LU TP 07-21
hep-ph
null
I give a short overview of what has been done in radiative and semileptonic Kaon decays in Chiral Perturbation Theory. This includes for semileptonic decays the work which has been done to order $p^6$ including preliminary results of isospin breaking to that order in $K_{\ell3}$. For the radiative decays I mainly present some results from recent work concerning $K_{\ell3\gamma}$.
[ { "created": "Tue, 3 Jul 2007 13:52:36 GMT", "version": "v1" } ]
2008-11-26
[ [ "Bijnens", "Johan", "" ] ]
I give a short overview of what has been done in radiative and semileptonic Kaon decays in Chiral Perturbation Theory. This includes for semileptonic decays the work which has been done to order $p^6$ including preliminary results of isospin breaking to that order in $K_{\ell3}$. For the radiative decays I mainly present some results from recent work concerning $K_{\ell3\gamma}$.
2003.12525
David Marzocca
Valerio Gherardi, David Marzocca, Elena Venturini
Matching scalar leptoquarks to the SMEFT at one loop
21 pages plus appendices. v:5 other corrections have been implemented
JHEP \textbf{07} (2020), 225
10.1007/JHEP07(2020)225
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we present the complete one-loop matching conditions, up to dimension-six operators of the Standard Model effective field theory, resulting by integrating out the two scalar leptoquarks $S_{1}$ and $S_{3}$. This allows a phenomenological study of low-energy constraints on this model at one-loop accuracy, which will be the focus of a subsequent work. Furthermore, it provides a rich comparison for functional and computational methods for one-loop matching, that are being developed. As a corollary result, we derive a complete set of dimension-six operators independent under integration by parts, but not under equations of motions, called Green's basis, as well as the complete reduction formulae from this set to the Warsaw basis.
[ { "created": "Fri, 27 Mar 2020 16:41:49 GMT", "version": "v1" }, { "created": "Tue, 21 Apr 2020 15:29:41 GMT", "version": "v2" }, { "created": "Fri, 17 Jul 2020 14:24:10 GMT", "version": "v3" }, { "created": "Mon, 23 Nov 2020 17:14:59 GMT", "version": "v4" }, { "created": "Tue, 16 Nov 2021 14:26:13 GMT", "version": "v5" } ]
2021-11-17
[ [ "Gherardi", "Valerio", "" ], [ "Marzocca", "David", "" ], [ "Venturini", "Elena", "" ] ]
In this paper we present the complete one-loop matching conditions, up to dimension-six operators of the Standard Model effective field theory, resulting by integrating out the two scalar leptoquarks $S_{1}$ and $S_{3}$. This allows a phenomenological study of low-energy constraints on this model at one-loop accuracy, which will be the focus of a subsequent work. Furthermore, it provides a rich comparison for functional and computational methods for one-loop matching, that are being developed. As a corollary result, we derive a complete set of dimension-six operators independent under integration by parts, but not under equations of motions, called Green's basis, as well as the complete reduction formulae from this set to the Warsaw basis.
hep-ph/0412356
Jin Min Yang
Guangping Gao, Robert J. Oakes, Jin Min Yang
Heavy Supersymmetric Particle Effects in Higgs Boson Production Associated with a Bottom Quark Pair at LHC and Tevatron
results for Tevatron added, version in PRD
Phys.Rev. D71 (2005) 095005
10.1103/PhysRevD.71.095005
null
hep-ph hep-ex
null
If all the supersymmetry particles (sparticles) except a light Higgs boson are too heavy to be directly produced at the Large Hadron Collider (LHC) and Tevatron, a possible way to reveal evidence for supersymmetry is through their virtual effects in other processes. We examine such supersymmetric QCD effects in bottom pair production associated with a light Higgs boson at the LHC and Tevatron. We find that if the relevant sparticles (gluinos and squarks) are well above the TeV scale, too heavy to be directly produced, they can still have sizable virtual effects in this process. For large $\tan\beta$, such residual effects can alter the production rate by as much as 40 percent, which should be observable in future measurements of this process.
[ { "created": "Thu, 23 Dec 2004 08:14:47 GMT", "version": "v1" }, { "created": "Sat, 30 Apr 2005 02:08:03 GMT", "version": "v2" } ]
2009-11-10
[ [ "Gao", "Guangping", "" ], [ "Oakes", "Robert J.", "" ], [ "Yang", "Jin Min", "" ] ]
If all the supersymmetry particles (sparticles) except a light Higgs boson are too heavy to be directly produced at the Large Hadron Collider (LHC) and Tevatron, a possible way to reveal evidence for supersymmetry is through their virtual effects in other processes. We examine such supersymmetric QCD effects in bottom pair production associated with a light Higgs boson at the LHC and Tevatron. We find that if the relevant sparticles (gluinos and squarks) are well above the TeV scale, too heavy to be directly produced, they can still have sizable virtual effects in this process. For large $\tan\beta$, such residual effects can alter the production rate by as much as 40 percent, which should be observable in future measurements of this process.
2010.03565
Yuber F. Perez-Gonzalez
Yuber F. Perez-Gonzalez, Jessica Turner
Assessing the tension between a black hole dominated early universe and leptogenesis
7+3 pages, 6 figures; one figure, comments, and references added, Boltzmann equations improved, main conclusion unchanged
null
10.1103/PhysRevD.104.103021
FERMILAB-PUB-20-528-T, NUHEP-TH/20-10, IPPP/20/46
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
We perform the first numerical calculation of the interplay between thermal and black hole induced leptogenesis, demonstrating that the right-handed neutrino surplus produced during the evaporation only partially mitigates the entropy dilution suffered by the thermal component. As such, the intermediate-mass regime of the right-handed neutrinos, $10^6{\rm~GeV} \lesssim M_{N} \lesssim 10^{9}{\rm~GeV}$, could not explain the observed baryon asymmetry even for fine-tuned scenarios if there existed a primordial black hole dominated era, consistent with initial black hole masses of $M_i \gtrsim \mathcal{O}\left(1\right)$ kg. Detection of the gravitational waves emitted from the same primordial black holes would place intermediate-scale thermal leptogenesis under tension.
[ { "created": "Wed, 7 Oct 2020 18:00:00 GMT", "version": "v1" }, { "created": "Thu, 18 Mar 2021 23:56:47 GMT", "version": "v2" } ]
2021-12-01
[ [ "Perez-Gonzalez", "Yuber F.", "" ], [ "Turner", "Jessica", "" ] ]
We perform the first numerical calculation of the interplay between thermal and black hole induced leptogenesis, demonstrating that the right-handed neutrino surplus produced during the evaporation only partially mitigates the entropy dilution suffered by the thermal component. As such, the intermediate-mass regime of the right-handed neutrinos, $10^6{\rm~GeV} \lesssim M_{N} \lesssim 10^{9}{\rm~GeV}$, could not explain the observed baryon asymmetry even for fine-tuned scenarios if there existed a primordial black hole dominated era, consistent with initial black hole masses of $M_i \gtrsim \mathcal{O}\left(1\right)$ kg. Detection of the gravitational waves emitted from the same primordial black holes would place intermediate-scale thermal leptogenesis under tension.
2404.14917
Muhammad Waheed Aslam
M.W. Aslam, A.A. Zafar, M.N. Aslam, A.A Bhatti, T. Hussain, and M. Iqbal
Particle Swarm Optimization Based Analysis to Unlocking the Neutrino Mass Puzzle using $A_{4}\times Z_{3}\times Z_{10}$ Flavor Symmetry
20 Pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
New research has highlighted a shortfall in the Standard Model (SM) because it predicts neutrinos to have zero mass. However, recent experiments on neutrino oscillation have revealed that the majority of neutrino parameters indeed indicate their significant mass. In response, scientists are increasingly incorporating discrete symmetries alongside continuous ones for better justification of observed patterns of neutrino mixing. In this study, we have examined a model within $A_4\times Z_3\times Z_{10}$ symmetry to estimate the neutrino masses using particle swarm optimization technique for both mass hierarchy of neutrino. This model employed a hybrid seesaw mechanism, a combination of seesaw mechanism of type-I and type-II, to establish the effective Majorana neutrino mass matrix. After calculating the mass eigenvalues and lepton mixing matrix upto second order perturbation theory in this framework, this study seeks to investigate the scalar potential for vacuum expectation values (VEVs), optimize the parameters, $U_{PMNS}$ matrix, neutrino masses: $|{m_{1}^{\prime}}^N|=0.0292794-0.0435082\ eV$, $|{m_{2}^{\prime}}^N|=1.78893\times 10^{-18}-0.0293509\ eV$, $|{m_{3}^{\prime}}^N|=0.0307414-0.0471467\ eV$, $|{m_{1}^{\prime}}^I|=0.00982013-0.0453623\ eV$, $|{m_{2}^{\prime}}^I_|=0.0379702-0.0471197\ eV$, and $|{m_{3}^{\prime}}^I|=0.0122063-0.027544\ eV$, effective neutrino mass parameters: $\langle {m_{ee}} \rangle^N=(0.170-3.93)\times10^{-2}\ eV$, $\langle {m_{\beta}} \rangle^N=(0.471-1.39)\times10^{-2}\ eV$, $\langle {m_{ee}} \rangle^I=(1.85-4.55)\times10^{-2}\ eV$ and $\langle {m_{\beta}} \rangle^I=(2.26-4.56)\times10^{-2}\ eV$, are predicted for both mass hierarchy through particle swarm optimization (PSO), showing strong agreement with recent experimental findings.
[ { "created": "Tue, 23 Apr 2024 11:02:39 GMT", "version": "v1" }, { "created": "Wed, 1 May 2024 06:50:03 GMT", "version": "v2" } ]
2024-05-02
[ [ "Aslam", "M. W.", "" ], [ "Zafar", "A. A.", "" ], [ "Aslam", "M. N.", "" ], [ "Bhatti", "A. A", "" ], [ "Hussain", "T.", "" ], [ "Iqbal", "M.", "" ] ]
New research has highlighted a shortfall in the Standard Model (SM) because it predicts neutrinos to have zero mass. However, recent experiments on neutrino oscillation have revealed that the majority of neutrino parameters indeed indicate their significant mass. In response, scientists are increasingly incorporating discrete symmetries alongside continuous ones for better justification of observed patterns of neutrino mixing. In this study, we have examined a model within $A_4\times Z_3\times Z_{10}$ symmetry to estimate the neutrino masses using particle swarm optimization technique for both mass hierarchy of neutrino. This model employed a hybrid seesaw mechanism, a combination of seesaw mechanism of type-I and type-II, to establish the effective Majorana neutrino mass matrix. After calculating the mass eigenvalues and lepton mixing matrix upto second order perturbation theory in this framework, this study seeks to investigate the scalar potential for vacuum expectation values (VEVs), optimize the parameters, $U_{PMNS}$ matrix, neutrino masses: $|{m_{1}^{\prime}}^N|=0.0292794-0.0435082\ eV$, $|{m_{2}^{\prime}}^N|=1.78893\times 10^{-18}-0.0293509\ eV$, $|{m_{3}^{\prime}}^N|=0.0307414-0.0471467\ eV$, $|{m_{1}^{\prime}}^I|=0.00982013-0.0453623\ eV$, $|{m_{2}^{\prime}}^I_|=0.0379702-0.0471197\ eV$, and $|{m_{3}^{\prime}}^I|=0.0122063-0.027544\ eV$, effective neutrino mass parameters: $\langle {m_{ee}} \rangle^N=(0.170-3.93)\times10^{-2}\ eV$, $\langle {m_{\beta}} \rangle^N=(0.471-1.39)\times10^{-2}\ eV$, $\langle {m_{ee}} \rangle^I=(1.85-4.55)\times10^{-2}\ eV$ and $\langle {m_{\beta}} \rangle^I=(2.26-4.56)\times10^{-2}\ eV$, are predicted for both mass hierarchy through particle swarm optimization (PSO), showing strong agreement with recent experimental findings.
1707.07258
Wakutaka Nakano
Masahiro Ibe, Wakutaka Nakano, Yutaro Shoji, and Kazumine Suzuki
Migdal Effect in Dark Matter Direct Detection Experiments
calculation error in coherent neutrino-nucleus scattering fixed
null
10.1007/JHEP03(2018)194
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The elastic scattering of an atomic nucleus plays a central role in dark matter direct detection experiments. In those experiments, it is usually assumed that the atomic electrons around the nucleus of the target material immediately follow the motion of the recoil nucleus. In reality, however, it takes some time for the electrons to catch up, which results in ionization and excitation of the atoms. In previous studies, those effects are taken into account by using the so-called Migdal's approach, in which the final state ionization/excitation are treated separately from the nuclear recoil. In this paper, we reformulate the Migdal's approach so that the "atomic recoil" cross section is obtained coherently, where we make transparent the energy-momentum conservation and the probability conservation. We show that the final state ionization/excitation can enhance the detectability of rather light dark matter in the GeV mass range via the {\it nuclear} scattering. We also discuss the coherent neutrino-nucleus scattering, where the same effects are expected.
[ { "created": "Sun, 23 Jul 2017 07:45:25 GMT", "version": "v1" }, { "created": "Thu, 22 Mar 2018 11:09:08 GMT", "version": "v2" }, { "created": "Wed, 19 Jun 2019 12:34:47 GMT", "version": "v3" }, { "created": "Mon, 30 Mar 2020 07:21:30 GMT", "version": "v4" }, { "created": "Tue, 28 Nov 2023 10:07:08 GMT", "version": "v5" } ]
2023-11-29
[ [ "Ibe", "Masahiro", "" ], [ "Nakano", "Wakutaka", "" ], [ "Shoji", "Yutaro", "" ], [ "Suzuki", "Kazumine", "" ] ]
The elastic scattering of an atomic nucleus plays a central role in dark matter direct detection experiments. In those experiments, it is usually assumed that the atomic electrons around the nucleus of the target material immediately follow the motion of the recoil nucleus. In reality, however, it takes some time for the electrons to catch up, which results in ionization and excitation of the atoms. In previous studies, those effects are taken into account by using the so-called Migdal's approach, in which the final state ionization/excitation are treated separately from the nuclear recoil. In this paper, we reformulate the Migdal's approach so that the "atomic recoil" cross section is obtained coherently, where we make transparent the energy-momentum conservation and the probability conservation. We show that the final state ionization/excitation can enhance the detectability of rather light dark matter in the GeV mass range via the {\it nuclear} scattering. We also discuss the coherent neutrino-nucleus scattering, where the same effects are expected.
2212.09174
Omar Medina
Francisco J. de Anda, Omar Medina, Jos\'e W.F. Valle, Carlos A. Vaquera-Araujo
Revamping Kaluza-Klein dark matter in an orbifold theory of flavor
14 pages, 3 figures, 2 tables. Your comments are very welcome! v2: correct affiliations
null
null
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
We suggest a common origin for dark matter, neutrino mass and family symmetry within the orbifold theory proposed in [arXiv:1910.05605v2,arXiv:2004.06735v2]. Flavor physics is described by an $A_4$ family symmetry that results naturally from compactification. WIMP Dark matter emerges from the first Kaluza-Klein excitation of the same scalar that drives family symmetry breaking and neutrino masses through the inverse seesaw mechanism. In addition to the "golden" quark-lepton mass relation and neutrino predictions for $0\nu\beta\beta$ decay, the model provides a good global description of all flavor observables.
[ { "created": "Sun, 18 Dec 2022 21:32:56 GMT", "version": "v1" }, { "created": "Wed, 21 Dec 2022 15:21:11 GMT", "version": "v2" } ]
2022-12-22
[ [ "de Anda", "Francisco J.", "" ], [ "Medina", "Omar", "" ], [ "Valle", "José W. F.", "" ], [ "Vaquera-Araujo", "Carlos A.", "" ] ]
We suggest a common origin for dark matter, neutrino mass and family symmetry within the orbifold theory proposed in [arXiv:1910.05605v2,arXiv:2004.06735v2]. Flavor physics is described by an $A_4$ family symmetry that results naturally from compactification. WIMP Dark matter emerges from the first Kaluza-Klein excitation of the same scalar that drives family symmetry breaking and neutrino masses through the inverse seesaw mechanism. In addition to the "golden" quark-lepton mass relation and neutrino predictions for $0\nu\beta\beta$ decay, the model provides a good global description of all flavor observables.
0811.1024
Andreas Weiler
Maxim Perelstein, Andreas Weiler
Polarized Tops from Stop Decays at the LHC
19 pages, 9 figures, reference and note added
JHEP 0903:141,2009
10.1088/1126-6708/2009/03/141
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In supersymmetric models, scalar top quarks, or stops, generically have parity-violating couplings to top quarks. As a result, tops produced in stop decays should be polarized. In this paper, we will argue that this effect may be observable at the LHC with realistic integrated luminosities, provided that one of the stops is copiously produced and can decay to a top and a neutralino. We define the "effective" stop mixing angle, which determines the degree of top polarization, and discuss the prospects for a measurement of this angle at the LHC. If some information about the neutralino mixing matrix is available, this measurement can be used to constrain the mixing angle in the stop sector, one of the most important ingredients in assessing the naturalness of electroweak symmetry breaking in the MSSM.
[ { "created": "Thu, 6 Nov 2008 20:34:00 GMT", "version": "v1" }, { "created": "Wed, 7 Jan 2009 16:06:36 GMT", "version": "v2" } ]
2009-04-03
[ [ "Perelstein", "Maxim", "" ], [ "Weiler", "Andreas", "" ] ]
In supersymmetric models, scalar top quarks, or stops, generically have parity-violating couplings to top quarks. As a result, tops produced in stop decays should be polarized. In this paper, we will argue that this effect may be observable at the LHC with realistic integrated luminosities, provided that one of the stops is copiously produced and can decay to a top and a neutralino. We define the "effective" stop mixing angle, which determines the degree of top polarization, and discuss the prospects for a measurement of this angle at the LHC. If some information about the neutralino mixing matrix is available, this measurement can be used to constrain the mixing angle in the stop sector, one of the most important ingredients in assessing the naturalness of electroweak symmetry breaking in the MSSM.
0911.3351
Radhey Shyam
R. Shyam, O. Scholten, and H. Lenske
The associated photoproduction of K+ meson off proton within a coupled-channels K-matrix approach
30 pages, 23 figures, version to appear in Phys. Rev. C
Phys.Rev.C81:015204,2010
10.1103/PhysRevC.81.015204
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the p(gamma,K+)Lambda and p(gamma,K+)Sigma^0 reactions within a coupled-channels effective-Lagrangian method which is based on the K-matrix approach. The two-body final channels included are pi-N, eta-N, phi-N, rho-N, gamma-N, K-Lambda, and K-Sigma. Non-resonant meson-baryon interactions are included in the model via nucleon intermediate states in the s- and u-channels and meson exchanges in the t-channel amplitude and the u-channel resonances. The nucleon resonances S11 (1535), S11 (1650), S31 (1620), P11 (1440), P11 (1710), P13 (1720), P33 (1232), P33 (1600), D13 (1520), D13 (1700), and D33 (1700) are included explicitly in the calculations. With a single parameter set which was derived earlier from our analysis of the eta meson photoproduction, the model describes well all the available cross section and polarization data of the SAPHIR collaboration for the two investigated channels. The description of the data of the CLAS collaboration, however, is not of the same quality. In contrast to some previous studies, we do not find any compelling need for including a D13 state with mass of around 2.0 GeV in order to reproduce the data for the p(gamma,K+)Lambda reaction at photon energies corresponding to the invariant mass around 1.9 GeV.
[ { "created": "Tue, 17 Nov 2009 17:31:27 GMT", "version": "v1" }, { "created": "Wed, 6 Jan 2010 13:22:41 GMT", "version": "v2" } ]
2010-04-06
[ [ "Shyam", "R.", "" ], [ "Scholten", "O.", "" ], [ "Lenske", "H.", "" ] ]
We investigate the p(gamma,K+)Lambda and p(gamma,K+)Sigma^0 reactions within a coupled-channels effective-Lagrangian method which is based on the K-matrix approach. The two-body final channels included are pi-N, eta-N, phi-N, rho-N, gamma-N, K-Lambda, and K-Sigma. Non-resonant meson-baryon interactions are included in the model via nucleon intermediate states in the s- and u-channels and meson exchanges in the t-channel amplitude and the u-channel resonances. The nucleon resonances S11 (1535), S11 (1650), S31 (1620), P11 (1440), P11 (1710), P13 (1720), P33 (1232), P33 (1600), D13 (1520), D13 (1700), and D33 (1700) are included explicitly in the calculations. With a single parameter set which was derived earlier from our analysis of the eta meson photoproduction, the model describes well all the available cross section and polarization data of the SAPHIR collaboration for the two investigated channels. The description of the data of the CLAS collaboration, however, is not of the same quality. In contrast to some previous studies, we do not find any compelling need for including a D13 state with mass of around 2.0 GeV in order to reproduce the data for the p(gamma,K+)Lambda reaction at photon energies corresponding to the invariant mass around 1.9 GeV.
1103.5980
Nobuaki Kurahashi
Yuki Adachi, Nobuaki Kurahashi, C. S. Lim and Nobuhito Maru
D^0-\bar D^0 Mixing in Gauge-Higgs Unification
26 pages, 12 figures. arXiv admin note: text overlap with arXiv:1005.2455
JHEP 1201 (2012) 047
10.1007/JHEP01(2012)047
KOBE-TH-11-04
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss flavor mixing and resulting Flavor Changing Neutral Current (FCNC) in the SU(3) \otimes SU(3)_color gauge-Higgs unification. As the FCNC process we calculate the rate of D^0-\bar D^0 mixing due to the exchange of non-zero Kaluza-Klein gluons at the tree level. Flavor mixing is argued to be realized by the fact that the bulk mass term and brane localized mass term is not diagonalized simultaneously unless bulk masses are degenerate. It is shown that automatic suppression mechanism is operative for the FCNC processes of light quarks. We therefore obtain a lower bound on the compactification scale of order \cal O(TeV) by comparing our prediction on the mass difference of neutral D meson with the recent experimental data, which is much milder than what we naively expect assuming only the decoupling of non-zero Kaluza-Klein gluons.
[ { "created": "Wed, 30 Mar 2011 16:10:42 GMT", "version": "v1" }, { "created": "Fri, 3 Jun 2011 05:01:28 GMT", "version": "v2" }, { "created": "Thu, 9 Jun 2011 12:26:50 GMT", "version": "v3" }, { "created": "Sun, 16 Oct 2011 23:36:08 GMT", "version": "v4" }, { "created": "Mon, 5 Dec 2011 08:11:41 GMT", "version": "v5" } ]
2012-01-17
[ [ "Adachi", "Yuki", "" ], [ "Kurahashi", "Nobuaki", "" ], [ "Lim", "C. S.", "" ], [ "Maru", "Nobuhito", "" ] ]
We discuss flavor mixing and resulting Flavor Changing Neutral Current (FCNC) in the SU(3) \otimes SU(3)_color gauge-Higgs unification. As the FCNC process we calculate the rate of D^0-\bar D^0 mixing due to the exchange of non-zero Kaluza-Klein gluons at the tree level. Flavor mixing is argued to be realized by the fact that the bulk mass term and brane localized mass term is not diagonalized simultaneously unless bulk masses are degenerate. It is shown that automatic suppression mechanism is operative for the FCNC processes of light quarks. We therefore obtain a lower bound on the compactification scale of order \cal O(TeV) by comparing our prediction on the mass difference of neutral D meson with the recent experimental data, which is much milder than what we naively expect assuming only the decoupling of non-zero Kaluza-Klein gluons.
hep-ph/0406255
Alan Kostelecky
Alan Kostelecky and Matthew Mewes
Lorentz Violation and Short-Baseline Neutrino Experiments
4 pages REVTeX
Phys.Rev.D70:076002,2004
10.1103/PhysRevD.70.076002
IUHET 470, June 2004
hep-ph
null
A general discussion is given of signals for broken Lorentz symmetry in short-baseline neutrino experiments. Among the effects that Lorentz violation can introduce are a dependence on energy differing from that of the usual massive-neutrino solution and a dependence on the direction of neutrino propagation. Using the results of the LSND experiment, explicit analysis of the effects of broken Lorentz symmetry yields a nonzero value (3+/-1) x 10^{-19} GeV for a combination of coefficients for Lorentz violation. This lies in the range expected for effects originating from the Planck scale in an underlying unified theory.
[ { "created": "Wed, 23 Jun 2004 13:34:30 GMT", "version": "v1" } ]
2008-11-26
[ [ "Kostelecky", "Alan", "" ], [ "Mewes", "Matthew", "" ] ]
A general discussion is given of signals for broken Lorentz symmetry in short-baseline neutrino experiments. Among the effects that Lorentz violation can introduce are a dependence on energy differing from that of the usual massive-neutrino solution and a dependence on the direction of neutrino propagation. Using the results of the LSND experiment, explicit analysis of the effects of broken Lorentz symmetry yields a nonzero value (3+/-1) x 10^{-19} GeV for a combination of coefficients for Lorentz violation. This lies in the range expected for effects originating from the Planck scale in an underlying unified theory.
hep-ph/9506315
null
Aaron K. Grant, Jonathan L. Rosner, Andre Martin, Jean-Marc Richard, and Joachim Stubbe
Spacings of Quarkonium Levels with the Same Principal Quantum Number
20 pages, latex, 3 uuencoded figures submitted separately (process using psfig.sty)
Phys.Rev.D53:2742-2751,1996
10.1103/PhysRevD.53.2742
EFI-95-22
hep-ph
null
The spacings between bound-state levels of the Schr\"odinger equation with the same principal quantum number $N$ but orbital angular momenta $\ell$ differing by unity are found to be nearly equal for a wide range of power potentials $V = \lambda r^\nu$, with $E_{N \ell} \approx F(\nu, N) - G(\nu,N) \ell$. Semiclassical approximations are in accord with this behavior. The result is applied to estimates of masses for quarkonium levels which have not yet been observed, including the 2P $c \bar c$ states and the 1D $b \bar b$ states.
[ { "created": "Tue, 13 Jun 1995 15:17:17 GMT", "version": "v1" } ]
2014-11-17
[ [ "Grant", "Aaron K.", "" ], [ "Rosner", "Jonathan L.", "" ], [ "Martin", "Andre", "" ], [ "Richard", "Jean-Marc", "" ], [ "Stubbe", "Joachim", "" ] ]
The spacings between bound-state levels of the Schr\"odinger equation with the same principal quantum number $N$ but orbital angular momenta $\ell$ differing by unity are found to be nearly equal for a wide range of power potentials $V = \lambda r^\nu$, with $E_{N \ell} \approx F(\nu, N) - G(\nu,N) \ell$. Semiclassical approximations are in accord with this behavior. The result is applied to estimates of masses for quarkonium levels which have not yet been observed, including the 2P $c \bar c$ states and the 1D $b \bar b$ states.
hep-ph/9505373
Lev F. M.
Felix M. Lev
Forms of Relativistic Dynamics, Current Operators and Deep Inelastic Lepton-Nucleon Scattering
9 pages, LaTeX
null
null
null
hep-ph
null
The three well-known forms of relativistic dynamics are unitarily equivalent and the problem of constructing the current operators can be solved in any form. However the notion of the impulse approximation is reasonable only in the point form. In particular, the parton model which is the consequence of the impulse approximation in the front form is incompatible with Lorentz invariance, P invariance and T invariance. The results for deep inelastic scattering based on the impulse approximation in the point form give natural qualitative explanation of the fact that the values given by the parton model sum rules exceed the corresponding experimental quantities.
[ { "created": "Wed, 24 May 1995 11:15:49 GMT", "version": "v1" } ]
2007-05-23
[ [ "Lev", "Felix M.", "" ] ]
The three well-known forms of relativistic dynamics are unitarily equivalent and the problem of constructing the current operators can be solved in any form. However the notion of the impulse approximation is reasonable only in the point form. In particular, the parton model which is the consequence of the impulse approximation in the front form is incompatible with Lorentz invariance, P invariance and T invariance. The results for deep inelastic scattering based on the impulse approximation in the point form give natural qualitative explanation of the fact that the values given by the parton model sum rules exceed the corresponding experimental quantities.
hep-ph/0312238
Masayasu Harada
Masayasu Harada (Nagoya Univ.)
Formulation of Vector Manifestation in Hot and/or Dense Matter
10 pages, no figures. Talk given at Finite Density QCD at Nara, July 10-12, 2003, Nara Prefecture Public Hall ``Big Roof'', Nara, Japan
Prog.Theor.Phys.Suppl.153:165-173,2004
10.1143/PTPS.153.165
DPNU-03-27
hep-ph nucl-th
null
The vector manifestation (VM) was proposed as a novel manifestation of chiral symmetry in which the massless vector meson becomes the chiral partner of pion. In this write-up, I briefly summarize the following main ingredients to formulate the VM in hot and/or dense matter: Effective field theory (EFT) based on the hidden local symmetry; Wilsonian matching between the EFT and QCD; Intrinsic thermal and/or dense effects.
[ { "created": "Wed, 17 Dec 2003 16:13:34 GMT", "version": "v1" } ]
2008-11-26
[ [ "Harada", "Masayasu", "", "Nagoya Univ." ] ]
The vector manifestation (VM) was proposed as a novel manifestation of chiral symmetry in which the massless vector meson becomes the chiral partner of pion. In this write-up, I briefly summarize the following main ingredients to formulate the VM in hot and/or dense matter: Effective field theory (EFT) based on the hidden local symmetry; Wilsonian matching between the EFT and QCD; Intrinsic thermal and/or dense effects.
1801.08525
Thomas G. Rizzo
Thomas G. Rizzo
Kinetic Mixing, Dark Photons and an Extra Dimension: I
44 pages,13 figs; discussion, figure and references updated, typos fixed; title changed for journal
null
10.1007/JHEP07(2018)118
SLAC-PUB-17178
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Extra dimensions (ED) can provide a useful tool for model-building. In this paper we introduce a single, flat ED extension of the kinetic-mixing/dark photon (DP) portal for dark matter (DM) interactions with the Standard Model (SM) assuming a compactification `radius' of order $R^{-1}\sim10-1000$ MeV and examine the resulting modifications to and augmentation of the usual DP phenomenology. In the present scenario, both the DP and DM experience the full 5-D while the SM fields are constrained to lie on a 4-D brane at the boundary of the ED. Such a setup can naturally yield the observed value of the DM relic density and explain the required rough degeneracy of the DM and DP masses needed to obtain it. Gauge symmetry breaking can occur via boundary conditions without the introduction of an additional singlet Higgs scalar thus avoiding all constraints associated with the coupling of such a field to the usual SM Higgs field in 5-D. The self-consistency of the field redefinitions that map the gauge fields into a canonical basis and thus removing the kinetic mixing terms is found to lead to a strong model building constraint on the ED setup involving a brane localized kinetic term for the 5-D gauge field on the SM brane. Multiple variations of this scenario are found to be possible which are consistent with all current experimental constraints but which predict very different phenomenologies. In this paper, after setting up the general model formalism, we discuss in detail the case of a complex scalar 5-D DM field, consistent with constraints arising from the CMB, which may or may not obtain a vacuum expectation value (vev). The resulting Kaluza-Klein (KK) towers of both the DM and DP fields are found to yield interesting and distinctive signatures.
[ { "created": "Thu, 25 Jan 2018 18:44:23 GMT", "version": "v1" }, { "created": "Fri, 2 Feb 2018 15:17:28 GMT", "version": "v2" }, { "created": "Wed, 4 Apr 2018 13:23:44 GMT", "version": "v3" }, { "created": "Wed, 25 Apr 2018 16:20:10 GMT", "version": "v4" }, { "created": "Tue, 3 Jul 2018 16:51:16 GMT", "version": "v5" }, { "created": "Wed, 11 Jul 2018 12:54:09 GMT", "version": "v6" } ]
2018-08-15
[ [ "Rizzo", "Thomas G.", "" ] ]
Extra dimensions (ED) can provide a useful tool for model-building. In this paper we introduce a single, flat ED extension of the kinetic-mixing/dark photon (DP) portal for dark matter (DM) interactions with the Standard Model (SM) assuming a compactification `radius' of order $R^{-1}\sim10-1000$ MeV and examine the resulting modifications to and augmentation of the usual DP phenomenology. In the present scenario, both the DP and DM experience the full 5-D while the SM fields are constrained to lie on a 4-D brane at the boundary of the ED. Such a setup can naturally yield the observed value of the DM relic density and explain the required rough degeneracy of the DM and DP masses needed to obtain it. Gauge symmetry breaking can occur via boundary conditions without the introduction of an additional singlet Higgs scalar thus avoiding all constraints associated with the coupling of such a field to the usual SM Higgs field in 5-D. The self-consistency of the field redefinitions that map the gauge fields into a canonical basis and thus removing the kinetic mixing terms is found to lead to a strong model building constraint on the ED setup involving a brane localized kinetic term for the 5-D gauge field on the SM brane. Multiple variations of this scenario are found to be possible which are consistent with all current experimental constraints but which predict very different phenomenologies. In this paper, after setting up the general model formalism, we discuss in detail the case of a complex scalar 5-D DM field, consistent with constraints arising from the CMB, which may or may not obtain a vacuum expectation value (vev). The resulting Kaluza-Klein (KK) towers of both the DM and DP fields are found to yield interesting and distinctive signatures.
2207.07677
Jacek Ksawery Osi\'nski
Paola Arias, Nicol\'as Bernal, Jacek K. Osi\'nski, Leszek Roszkowski
Dark Matter Axions in the Early Universe with a Period of Increasing Temperature
28 pages, 8 figures; updated to match published version
null
10.1088/1475-7516/2023/05/028
PI/UAN-2022-719FT
hep-ph astro-ph.CO hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the production of axion dark matter through the misalignment mechanism in the context of a nonstandard cosmological history involving early matter domination by a scalar field with a time-dependent decay rate. In cases where the temperature of the Universe experiences a temporary period of increase, Hubble friction can be restored in the evolution of the axion field, resulting in the possibility of up to three "crossings" of the axion mass and the Hubble expansion rate. This has the effect of dynamically resetting the misalignment mechanism to a new initial state for a second distinct phase of oscillation. The resultant axion mass required for the present dark matter relic density is never bigger than the standard-history window and can be smaller by more than three orders of magnitude, which can be probed by upcoming experiments such as ABRACADABRA, KLASH, ADMX, MADMAX, and ORGAN, targeting the axion-photon coupling. This highlights the possibility of exploring the cosmological history prior to Big Bang Nucleosynthesis through searches for axion dark matter beyond the standard window.
[ { "created": "Fri, 15 Jul 2022 18:00:32 GMT", "version": "v1" }, { "created": "Wed, 5 Apr 2023 09:22:15 GMT", "version": "v2" } ]
2023-05-24
[ [ "Arias", "Paola", "" ], [ "Bernal", "Nicolás", "" ], [ "Osiński", "Jacek K.", "" ], [ "Roszkowski", "Leszek", "" ] ]
We consider the production of axion dark matter through the misalignment mechanism in the context of a nonstandard cosmological history involving early matter domination by a scalar field with a time-dependent decay rate. In cases where the temperature of the Universe experiences a temporary period of increase, Hubble friction can be restored in the evolution of the axion field, resulting in the possibility of up to three "crossings" of the axion mass and the Hubble expansion rate. This has the effect of dynamically resetting the misalignment mechanism to a new initial state for a second distinct phase of oscillation. The resultant axion mass required for the present dark matter relic density is never bigger than the standard-history window and can be smaller by more than three orders of magnitude, which can be probed by upcoming experiments such as ABRACADABRA, KLASH, ADMX, MADMAX, and ORGAN, targeting the axion-photon coupling. This highlights the possibility of exploring the cosmological history prior to Big Bang Nucleosynthesis through searches for axion dark matter beyond the standard window.
2202.13178
Gorazd Cvetic
C\'esar Ayala, Gorazd Cveti\v{c} and Diego Teca
Extraction of $\alpha_s$ using Borel-Laplace sum rules for tau decay data
4 pages, 1 figure, based on a presentation at: "alphas-2022: Workshop on precision measurements of the QCD coupling constant," January 31 - February 4, 2022, ECT* Trento, Italy; written for the Snowmass-2022 White Paper (The strong coupling constant: State of the art and the decade ahead)
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Double-pinched Borel-Laplace sum rules are applied to ALEPH $\tau$-decay data. For the leading-twist ($D=0$) Adler function a renormalon-motivated extension is used, and the 5-loop coefficient is taken to be $d_4=275 \pm 63$. Two $D=6$ terms appear in the truncated OPE ($D \leq 6$) to enable cancellation of the corresponding renormalon ambiguities. Two variants of the fixed order perturbation theory, and the inverse Borel transform, are applied to the evaluation of the $D=0$ contribution. Truncation index $N_t$ is fixed by the requirement of local insensitivity of the momenta $a^{(2,0)}$ and $a^{(2,1)}$ under variation of $N_t$. The averaged value of the coupling obtained is $\alpha_s(m_{\tau}^2)=0.3235^{+0.0138}_{-0.0126}$ [$\alpha_s(M_Z^2)=0.1191 \pm 0.0016$]. The theoretical uncertainties are significantly larger than the experimental ones.
[ { "created": "Sat, 26 Feb 2022 16:33:59 GMT", "version": "v1" } ]
2022-03-01
[ [ "Ayala", "César", "" ], [ "Cvetič", "Gorazd", "" ], [ "Teca", "Diego", "" ] ]
Double-pinched Borel-Laplace sum rules are applied to ALEPH $\tau$-decay data. For the leading-twist ($D=0$) Adler function a renormalon-motivated extension is used, and the 5-loop coefficient is taken to be $d_4=275 \pm 63$. Two $D=6$ terms appear in the truncated OPE ($D \leq 6$) to enable cancellation of the corresponding renormalon ambiguities. Two variants of the fixed order perturbation theory, and the inverse Borel transform, are applied to the evaluation of the $D=0$ contribution. Truncation index $N_t$ is fixed by the requirement of local insensitivity of the momenta $a^{(2,0)}$ and $a^{(2,1)}$ under variation of $N_t$. The averaged value of the coupling obtained is $\alpha_s(m_{\tau}^2)=0.3235^{+0.0138}_{-0.0126}$ [$\alpha_s(M_Z^2)=0.1191 \pm 0.0016$]. The theoretical uncertainties are significantly larger than the experimental ones.
hep-ph/9910548
Vladimir Lugovoi
Vladimir Lugovoi (PTI, Tashkent, Uzbekistan)
Production of fast hadron leader by QCD process
9 pages, 2 figures
null
null
176-99-HEP
hep-ph
null
An algorithm of Monte Carlo code for the production of fast hadron leader in the (anti)proton-proton interaction by QCD process is discussed.
[ { "created": "Fri, 29 Oct 1999 18:58:50 GMT", "version": "v1" } ]
2007-05-23
[ [ "Lugovoi", "Vladimir", "", "PTI, Tashkent, Uzbekistan" ] ]
An algorithm of Monte Carlo code for the production of fast hadron leader in the (anti)proton-proton interaction by QCD process is discussed.
1505.08017
Simon Mollet
Jean-Marie Fr\`ere, Maxim Libanov, Simon Mollet, Sergey Troitsky
Flavour changing $Z'$ signals in a 6D inspired model
14 pages, 1 figure
null
10.1007/JHEP06(2016)063
ULB-TH/15-07, INR-TH-2015-012
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the phenomenology of new neutral gauge bosons with flavour non-diagonal couplings to fermions, inherent in 6D models explaining successfully the hierarchy of masses as well as the mixing for quarks, charged leptons and neutrinos (this model can in particular be credited with the correct prediction of the neutrino mixing angle $\theta_{13}$). We present a general relation between masses of new gauge bosons and their couplings to fermions. We show that in the current realization of the model, the new heavy bosons are unreachable at LHC but argue why the constraint could be relaxed in the context of a different realization. In view of a more systematic study, we use an effective model inspired by the above to relate directly rare meson decays to possible LHC observations. In terms of effective Lagrangians, this can be seen as the introduction in the model of only one overall scaling parameter to extend our approach without modifying the 4D (gauge) structure.
[ { "created": "Fri, 29 May 2015 12:31:06 GMT", "version": "v1" }, { "created": "Mon, 7 Dec 2015 11:14:33 GMT", "version": "v2" }, { "created": "Mon, 25 Apr 2016 12:33:54 GMT", "version": "v3" } ]
2016-06-29
[ [ "Frère", "Jean-Marie", "" ], [ "Libanov", "Maxim", "" ], [ "Mollet", "Simon", "" ], [ "Troitsky", "Sergey", "" ] ]
We consider the phenomenology of new neutral gauge bosons with flavour non-diagonal couplings to fermions, inherent in 6D models explaining successfully the hierarchy of masses as well as the mixing for quarks, charged leptons and neutrinos (this model can in particular be credited with the correct prediction of the neutrino mixing angle $\theta_{13}$). We present a general relation between masses of new gauge bosons and their couplings to fermions. We show that in the current realization of the model, the new heavy bosons are unreachable at LHC but argue why the constraint could be relaxed in the context of a different realization. In view of a more systematic study, we use an effective model inspired by the above to relate directly rare meson decays to possible LHC observations. In terms of effective Lagrangians, this can be seen as the introduction in the model of only one overall scaling parameter to extend our approach without modifying the 4D (gauge) structure.
hep-ph/0406212
Wei Zhu
Wei Zhu, Zhenqi Shen and Jianhong Ruan
Parton recombination effect in polarized parton distributions
25 pages, 1 figure, to be published in Nucl. Phys. B. Appendix is corrected
Nucl.Phys.B692:417-433,2004
10.1016/j.nuclphysb.2004.06.001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Parton recombination corrections to the standard spin-dependent Altarelli-Parisi evolution equation are considered in a nonlinear evolution equation. The properties of this recombination equation and its relation with the spin-averaged form are discussed.
[ { "created": "Mon, 21 Jun 2004 04:08:27 GMT", "version": "v1" }, { "created": "Wed, 22 Jan 2014 22:34:48 GMT", "version": "v2" } ]
2014-01-24
[ [ "Zhu", "Wei", "" ], [ "Shen", "Zhenqi", "" ], [ "Ruan", "Jianhong", "" ] ]
Parton recombination corrections to the standard spin-dependent Altarelli-Parisi evolution equation are considered in a nonlinear evolution equation. The properties of this recombination equation and its relation with the spin-averaged form are discussed.
1710.10179
Dorota Strozik-Kotlorz
D. Strozik-Kotlorz, S.V. Mikhailov, O.V. Teryaev and A. Kotlorz
Nucleon structure functions in the truncated moments approach
6 pages, 3 figures, presented at XVII Workshop on High Energy Spin Physics DSPIN-17, September 11-15 2017, Dubna, Russia
J. Phys. Conf. Ser. 938 (2017) 1, 012062
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We demonstrate advantages of the truncated Mellin moments (TMM) approach in the analysis of DIS data. We present a novel method for determination of the Bjorken sum rule (BSR) from restricted in $x$ variable experimental data. We show how to incorporate different uncertainties for each kinematic bin. We apply our analysis to recent COMPASS data.
[ { "created": "Fri, 27 Oct 2017 14:45:40 GMT", "version": "v1" } ]
2020-07-24
[ [ "Strozik-Kotlorz", "D.", "" ], [ "Mikhailov", "S. V.", "" ], [ "Teryaev", "O. V.", "" ], [ "Kotlorz", "A.", "" ] ]
We demonstrate advantages of the truncated Mellin moments (TMM) approach in the analysis of DIS data. We present a novel method for determination of the Bjorken sum rule (BSR) from restricted in $x$ variable experimental data. We show how to incorporate different uncertainties for each kinematic bin. We apply our analysis to recent COMPASS data.
1506.00909
Paul Springer
Paul Springer, Bertram Klein
O(2)-scaling in finite and infinite volume
13 pages, 9 figerues
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The exact nature of the chiral phase transition in QCD is still under investigation. In $N_f=2$ and $N_f=(2+1)$ lattice simulations with staggered fermions the expected O($N$)-scaling behavior was observed. However, it is still not clear whether this behavior falls into the O(2) or O(4) universality class. To resolve this issue, a careful scaling and finite-size scaling analysis of the lattice results is needed. We use a functional renormalization group to perform a new investigation of the finite-size scaling regions in O(2)- and O(4)-models. We also investigate the behavior of the critical fluctuations by means of the $4^{\text{th}}$-order Binder cumulant. The finite-size analysis of this quantity provides an additional way for determining the universality class of the chiral phase transition in lattice QCD.
[ { "created": "Tue, 2 Jun 2015 14:55:35 GMT", "version": "v1" }, { "created": "Tue, 15 Sep 2015 07:12:03 GMT", "version": "v2" } ]
2015-09-16
[ [ "Springer", "Paul", "" ], [ "Klein", "Bertram", "" ] ]
The exact nature of the chiral phase transition in QCD is still under investigation. In $N_f=2$ and $N_f=(2+1)$ lattice simulations with staggered fermions the expected O($N$)-scaling behavior was observed. However, it is still not clear whether this behavior falls into the O(2) or O(4) universality class. To resolve this issue, a careful scaling and finite-size scaling analysis of the lattice results is needed. We use a functional renormalization group to perform a new investigation of the finite-size scaling regions in O(2)- and O(4)-models. We also investigate the behavior of the critical fluctuations by means of the $4^{\text{th}}$-order Binder cumulant. The finite-size analysis of this quantity provides an additional way for determining the universality class of the chiral phase transition in lattice QCD.
1812.04663
Salvador Centelles Chuli\'a
Peng Chen, Salvador Centelles Chuli\'a, Gui-Jun Ding, Rahul Srivastava and Jos\'e W. F. Valle
CP Symmetries as Guiding Posts: Revamping Tri-Bi-Maximal Mixing-I
21 pages, 4 figures
null
10.1007/JHEP03(2019)036
USTC-ICTS-18-21, IFIC18-XXX
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the possible generalized CP symmetries admitted by the Tri-Bi-Maximal (TBM) neutrino mixing. Taking advantage of these symmetries we construct in a systematic way other variants of the standard TBM ansatz. Depending on the type and number of generalized CP symmetries imposed, we get new mixing matrices, all of which related to the original TBM matrix. One of such "revamped" TBM variants is the recently discussed mixing matrix of arXiv:1806.03367. We also briefly discuss the phenomenological implications following from these mixing patterns.
[ { "created": "Tue, 11 Dec 2018 19:38:11 GMT", "version": "v1" } ]
2019-03-27
[ [ "Chen", "Peng", "" ], [ "Chuliá", "Salvador Centelles", "" ], [ "Ding", "Gui-Jun", "" ], [ "Srivastava", "Rahul", "" ], [ "Valle", "José W. F.", "" ] ]
We analyze the possible generalized CP symmetries admitted by the Tri-Bi-Maximal (TBM) neutrino mixing. Taking advantage of these symmetries we construct in a systematic way other variants of the standard TBM ansatz. Depending on the type and number of generalized CP symmetries imposed, we get new mixing matrices, all of which related to the original TBM matrix. One of such "revamped" TBM variants is the recently discussed mixing matrix of arXiv:1806.03367. We also briefly discuss the phenomenological implications following from these mixing patterns.
2212.11578
Gianluca Degli Esposti
Gianluca Degli Esposti, Greger Torgrimsson
Worldline instantons for the momentum spectrum of Schwinger pair production in space-time dependent fields
16 pages, 9 figures
null
10.1103/PhysRevD.107.056019
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show how to use the worldline-instanton formalism to calculate the momentum spectrum of the electron-positron pairs produced by an electric field that depends on both space and time. Using the LSZ reduction formula with a worldline representation for the propagator in a spacetime field, we make use of the saddle-point method to obtain a semiclassical approximation of the pair-production spectrum. In order to check the final result, we integrate the spectrum and compare with the results obtained using a previous instanton method for the imaginary part of the effective action.
[ { "created": "Thu, 22 Dec 2022 10:14:28 GMT", "version": "v1" } ]
2023-04-05
[ [ "Esposti", "Gianluca Degli", "" ], [ "Torgrimsson", "Greger", "" ] ]
We show how to use the worldline-instanton formalism to calculate the momentum spectrum of the electron-positron pairs produced by an electric field that depends on both space and time. Using the LSZ reduction formula with a worldline representation for the propagator in a spacetime field, we make use of the saddle-point method to obtain a semiclassical approximation of the pair-production spectrum. In order to check the final result, we integrate the spectrum and compare with the results obtained using a previous instanton method for the imaginary part of the effective action.
hep-ph/9712490
Mark Hindmarsh
Mark Hindmarsh (Sussex University)
Ordering Dynamics of Topological Defect Networks
4pp LaTeX2e. Uses a4 package. Talk given at Solitons 97, July 20--26 1997, Kingston ON, Canada
null
null
SUSX-TH-97-024
hep-ph
null
I report on some work in progress on the dynamics of extended objects in field theories after a rapid phase transition, as is relevant in the early Universe. An analytic technique, originally introduced to approximate the dynamics of topological defects in condensed matter systems, is extended to cover relativistic objects. An exact formula for the area density of domain walls in $D$ dimensions is derived.
[ { "created": "Mon, 22 Dec 1997 18:30:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Hindmarsh", "Mark", "", "Sussex University" ] ]
I report on some work in progress on the dynamics of extended objects in field theories after a rapid phase transition, as is relevant in the early Universe. An analytic technique, originally introduced to approximate the dynamics of topological defects in condensed matter systems, is extended to cover relativistic objects. An exact formula for the area density of domain walls in $D$ dimensions is derived.
0805.4786
Francesco Hautmann
F.Hautmann and H.Jung
Multi-jet production and transverse momentum dependent parton distributions
To appear in the Proceedings of the EPS-HEP 2007 Conference on High Energy Physics (Manchester, 19-25 July 2007)
null
10.1088/1742-6596/110/2/022017
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the impact of transverse-momentum dependent parton distributions on detailed features of multi-jet final states, focusing on angular jet correlations in DIS data.
[ { "created": "Fri, 30 May 2008 15:10:56 GMT", "version": "v1" } ]
2009-11-13
[ [ "Hautmann", "F.", "" ], [ "Jung", "H.", "" ] ]
We study the impact of transverse-momentum dependent parton distributions on detailed features of multi-jet final states, focusing on angular jet correlations in DIS data.
hep-ph/0312179
Chong Sheng Li
Li Lin Yang, Chong Sheng Li, Jian Jun Liu, Li Gang Jin
Production of Scalar Higgs Bosons Associated with $Z^0$ Boson at the CERN LHC in the MSSM
19 pages, 8 figures, RevTeX4; one reference added, minor changes, conclusion unchanged; Journal-ref added
J.Phys. G30 (2004) 1821-1835
10.1088/0954-3899/30/12/005
null
hep-ph
null
We investigate the associated production of a scalar Higgs boson ($h^0$ or $H^0$) with $Z^0$ boson in the minimal supersymmetric extension of the standard model (MSSM) at the CERN Large Hadron Collider (LHC), including the contributions from $b\bar{b}$ annihilation at the tree level and gluon fusion via quark and squark loops. We quantitatively analyze the total cross sections in the mSUGRA scenario. For the production of $h^0$ associated with $Z^0$, we find that in most of the parameter regions, the contributions from initial $b\bar{b}$ and $gg$ are at a level of one percent of the total cross section and therefore almost insignificant. For the production of $H^0$ associated with $Z^0$, the contributions from $b\bar{b}$ channel can be much larger than those from light quark initial states. Especially for large $\tan\beta$, the increment can reach about one order of magnitude. Thus, when considering the associated production of $H^0$ and $Z^0$ at the LHC, the contributions from $b\bar{b}$ annihilation should be taken into account seriously.
[ { "created": "Mon, 15 Dec 2003 12:39:16 GMT", "version": "v1" }, { "created": "Sat, 27 Mar 2004 03:58:39 GMT", "version": "v2" }, { "created": "Sun, 27 Jun 2004 17:03:50 GMT", "version": "v3" }, { "created": "Tue, 7 Dec 2004 14:20:08 GMT", "version": "v4" } ]
2009-11-10
[ [ "Yang", "Li Lin", "" ], [ "Li", "Chong Sheng", "" ], [ "Liu", "Jian Jun", "" ], [ "Jin", "Li Gang", "" ] ]
We investigate the associated production of a scalar Higgs boson ($h^0$ or $H^0$) with $Z^0$ boson in the minimal supersymmetric extension of the standard model (MSSM) at the CERN Large Hadron Collider (LHC), including the contributions from $b\bar{b}$ annihilation at the tree level and gluon fusion via quark and squark loops. We quantitatively analyze the total cross sections in the mSUGRA scenario. For the production of $h^0$ associated with $Z^0$, we find that in most of the parameter regions, the contributions from initial $b\bar{b}$ and $gg$ are at a level of one percent of the total cross section and therefore almost insignificant. For the production of $H^0$ associated with $Z^0$, the contributions from $b\bar{b}$ channel can be much larger than those from light quark initial states. Especially for large $\tan\beta$, the increment can reach about one order of magnitude. Thus, when considering the associated production of $H^0$ and $Z^0$ at the LHC, the contributions from $b\bar{b}$ annihilation should be taken into account seriously.
1309.3051
Jakub Wagner
H. Moutarde, B. Pire, F. Sabati\'e, L. Szymanowski, J. Wagner
Next to leading order analysis of DVCS and TCS
To be published in the proceedings of the INPC2013 conference
null
null
CPhT - PC -082 - 0813
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of $O(\alpha_s)$ QCD contributions to the timelike and spacelike virtual Compton scattering amplitudes in the generalized Bjorken scaling regime demonstrates that gluonic contributions are by no means negligible even in the medium energy range which will be studied intensely at JLab12 and in the COMPASS-II experiment at CERN.
[ { "created": "Thu, 12 Sep 2013 07:42:15 GMT", "version": "v1" } ]
2013-09-13
[ [ "Moutarde", "H.", "" ], [ "Pire", "B.", "" ], [ "Sabatié", "F.", "" ], [ "Szymanowski", "L.", "" ], [ "Wagner", "J.", "" ] ]
The study of $O(\alpha_s)$ QCD contributions to the timelike and spacelike virtual Compton scattering amplitudes in the generalized Bjorken scaling regime demonstrates that gluonic contributions are by no means negligible even in the medium energy range which will be studied intensely at JLab12 and in the COMPASS-II experiment at CERN.
1412.0018
David Curtin
David Curtin, Rouven Essig, Stefania Gori, Jessie Shelton
Illuminating Dark Photons with High-Energy Colliders
36 pages + references, 14 figures, 3 tables. Fixed typos, added references
null
10.1007/JHEP02(2015)157
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
High-energy colliders offer a unique sensitivity to dark photons, the mediators of a broken dark U(1) gauge theory that kinetically mixes with the Standard Model (SM) hypercharge. Dark photons can be detected in the exotic decay of the 125 GeV Higgs boson, h -> Z Z_D -> 4l, and in Drell-Yan events, pp -> Z_D -> ll. If the dark U(1) is broken by a hidden-sector Higgs mechanism, then mixing between the dark and SM Higgs bosons also allows the exotic decay h -> Z_D Z_D -> 4l. We show that the 14 TeV LHC and a 100 TeV proton-proton collider provide powerful probes of both exotic Higgs decay channels. In the case of kinetic mixing alone, direct Drell-Yan production offers the best sensitivity to Z_D, and can probe epsilon >~ 9 x 10^(-4) (4 x 10^(-4)) at the HL-LHC (100 TeV pp collider). The exotic Higgs decay h -> Z Z_D offers slightly weaker sensitivity, but both measurements are necessary to distinguish the kinetically mixed dark photon from other scenarios. If Higgs mixing is also present, then the decay h -> Z_D Z_D can allow sensitivity to the Z_D for epsilon >~ 10^(-9) - 10^(-6) (10^(-10) - 10^(-7)) for the mass range 2 m_mu < m_(Z_D) < m_h/2 by searching for displaced dark photon decays. We also compare the Z_D sensitivity at pp colliders to the indirect, but model-independent, sensitivity of global fits to electroweak precision observables. We perform a global electroweak fit of the dark photon model, substantially updating previous work in the literature. Electroweak precision measurements at LEP, Tevatron, and the LHC exclude epsilon as low as 3 x 10^(-2). Sensitivity can be improved by up to a factor of ~2 with HL-LHC data, and an additional factor of ~4 with ILC/GigaZ data.
[ { "created": "Fri, 28 Nov 2014 21:00:05 GMT", "version": "v1" }, { "created": "Fri, 27 Feb 2015 17:15:49 GMT", "version": "v2" } ]
2015-06-23
[ [ "Curtin", "David", "" ], [ "Essig", "Rouven", "" ], [ "Gori", "Stefania", "" ], [ "Shelton", "Jessie", "" ] ]
High-energy colliders offer a unique sensitivity to dark photons, the mediators of a broken dark U(1) gauge theory that kinetically mixes with the Standard Model (SM) hypercharge. Dark photons can be detected in the exotic decay of the 125 GeV Higgs boson, h -> Z Z_D -> 4l, and in Drell-Yan events, pp -> Z_D -> ll. If the dark U(1) is broken by a hidden-sector Higgs mechanism, then mixing between the dark and SM Higgs bosons also allows the exotic decay h -> Z_D Z_D -> 4l. We show that the 14 TeV LHC and a 100 TeV proton-proton collider provide powerful probes of both exotic Higgs decay channels. In the case of kinetic mixing alone, direct Drell-Yan production offers the best sensitivity to Z_D, and can probe epsilon >~ 9 x 10^(-4) (4 x 10^(-4)) at the HL-LHC (100 TeV pp collider). The exotic Higgs decay h -> Z Z_D offers slightly weaker sensitivity, but both measurements are necessary to distinguish the kinetically mixed dark photon from other scenarios. If Higgs mixing is also present, then the decay h -> Z_D Z_D can allow sensitivity to the Z_D for epsilon >~ 10^(-9) - 10^(-6) (10^(-10) - 10^(-7)) for the mass range 2 m_mu < m_(Z_D) < m_h/2 by searching for displaced dark photon decays. We also compare the Z_D sensitivity at pp colliders to the indirect, but model-independent, sensitivity of global fits to electroweak precision observables. We perform a global electroweak fit of the dark photon model, substantially updating previous work in the literature. Electroweak precision measurements at LEP, Tevatron, and the LHC exclude epsilon as low as 3 x 10^(-2). Sensitivity can be improved by up to a factor of ~2 with HL-LHC data, and an additional factor of ~4 with ILC/GigaZ data.
1511.06924
Mariaelena Boglione
Mariaelena Boglione and Alexei Prokudin
Phenomenology of transverse spin: past, present and future
20 pages, 21 figures, one comment and two references added
null
10.1140/epja/i2016-16154-6
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We summarize the most significant aspects in the study of transverse spin phenomena over the last few decades, focusing on Semi-Inclusive Deep Inelastic Scattering processes and hadronic production in $e^+e^-$ annihilations. The phenomenology of transverse momentum dependent distribution and fragmentation functions will be reviewed in an in-depth analysis of the most recent developments and of the future perspectives.
[ { "created": "Sat, 21 Nov 2015 21:07:18 GMT", "version": "v1" }, { "created": "Wed, 2 Dec 2015 09:04:07 GMT", "version": "v2" } ]
2016-07-20
[ [ "Boglione", "Mariaelena", "" ], [ "Prokudin", "Alexei", "" ] ]
We summarize the most significant aspects in the study of transverse spin phenomena over the last few decades, focusing on Semi-Inclusive Deep Inelastic Scattering processes and hadronic production in $e^+e^-$ annihilations. The phenomenology of transverse momentum dependent distribution and fragmentation functions will be reviewed in an in-depth analysis of the most recent developments and of the future perspectives.
1801.00917
Rumin Wang
Bin Wei, Jie Zhu, Jin-Huan Shen, Ru-Min Wang, Gong-Ru Lu
Probing the R-parity violating supersymmetric effects in $B_c\to J/\psi\ell^-\bar{\nu}_{\ell},\eta_c\ell^-\bar{\nu}_{\ell}$ and $\Lambda_b\to\Lambda_c\ell^-\bar{\nu}_{\ell}$ decays
21 pages, 5 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by recent $R_D$, $R_{D^*}$ and $R_{J/\psi}$ anomalies in $B\to D\ell^- \bar{\nu}_{\ell}$, $B\to D^*\ell^- \bar{\nu}_{\ell}$ and $B_c\to J/\psi\ell^- \bar{\nu}_{\ell}$ decays, respectively, we study possible R-parity violating supersymmetric effects in $B_c\to J/\psi\ell^- \bar{\nu}_{\ell},\eta_c\ell^- \bar{\nu}_{\ell}$ and $\Lambda_b \to \Lambda_c \ell^- \bar{\nu}_{\ell}$ decays, which are also induced by $b\to c \ell^- \bar{\nu}_{\ell}$ at quark level. We find that (I) the constrained slepton exchange couplings $\lambda_{i33}\tilde{\lambda}'^*_{i23}$ involving in $b\to c \tau^- \bar{\nu}_{\tau}$ transition from relevant latest experimental data still have quite large effects on all (differential) branching ratios and the normalized forward-backward asymmetries of the exclusive semileptonic $b\to c \tau^- \bar{\nu}_{\tau}$ decays as well as the ratios of the (differential) branching ratios; (II) after satisfying the data of $R_D$ and $R_{D^*}$, the upper limit of $R_{J/\psi}$, $R_{\eta_c}$ and $R_{\Lambda_c}$ could be increased by 10%, 112% and 24%, respectively, from their upper limits of the Standard Model predictions by the $\lambda_{i33}\tilde{\lambda}'^*_{i23}$ couplings. The results in this work could be used to probe R-parity violating effects and will correlate with searches for direct supersymmetric signals at the running LHCb and the forthcoming Belle-II.
[ { "created": "Wed, 3 Jan 2018 07:37:37 GMT", "version": "v1" } ]
2018-01-04
[ [ "Wei", "Bin", "" ], [ "Zhu", "Jie", "" ], [ "Shen", "Jin-Huan", "" ], [ "Wang", "Ru-Min", "" ], [ "Lu", "Gong-Ru", "" ] ]
Motivated by recent $R_D$, $R_{D^*}$ and $R_{J/\psi}$ anomalies in $B\to D\ell^- \bar{\nu}_{\ell}$, $B\to D^*\ell^- \bar{\nu}_{\ell}$ and $B_c\to J/\psi\ell^- \bar{\nu}_{\ell}$ decays, respectively, we study possible R-parity violating supersymmetric effects in $B_c\to J/\psi\ell^- \bar{\nu}_{\ell},\eta_c\ell^- \bar{\nu}_{\ell}$ and $\Lambda_b \to \Lambda_c \ell^- \bar{\nu}_{\ell}$ decays, which are also induced by $b\to c \ell^- \bar{\nu}_{\ell}$ at quark level. We find that (I) the constrained slepton exchange couplings $\lambda_{i33}\tilde{\lambda}'^*_{i23}$ involving in $b\to c \tau^- \bar{\nu}_{\tau}$ transition from relevant latest experimental data still have quite large effects on all (differential) branching ratios and the normalized forward-backward asymmetries of the exclusive semileptonic $b\to c \tau^- \bar{\nu}_{\tau}$ decays as well as the ratios of the (differential) branching ratios; (II) after satisfying the data of $R_D$ and $R_{D^*}$, the upper limit of $R_{J/\psi}$, $R_{\eta_c}$ and $R_{\Lambda_c}$ could be increased by 10%, 112% and 24%, respectively, from their upper limits of the Standard Model predictions by the $\lambda_{i33}\tilde{\lambda}'^*_{i23}$ couplings. The results in this work could be used to probe R-parity violating effects and will correlate with searches for direct supersymmetric signals at the running LHCb and the forthcoming Belle-II.
2112.15586
Ismail Zahed
Edward Shuryak and Ismail Zahed
Meson structure on the light-front III : The Hamiltonian, heavy quarkonia, spin and orbit mixing
37 pages, 8 figures
null
null
null
hep-ph hep-lat nucl-th
http://creativecommons.org/licenses/by/4.0/
This is the third paper on hadronic light front wave functions (LFWFs). We derive a light front Hamiltonian from first principles using the key features of the QCD vacuum at low resolution. In the first approximation, it gives transverse oscillator and longitudinal harmonic modes and yields the correct Regge trajectories. For heavy quarkonia, we compare its spectrum to that obtained from the usual Schroedinger equation in the rest frame. We use the same approach for light quarks, and investigate the role of confinement and chiral symmetry breaking in the quark-antiquark sector. We then study spin-spin and spin-orbit mixing, resulting in e.g. quadrupole moments of vector mesons. For the light mesons, we show how to extend the famed t$^\prime$Hooft interaction to the light front, which solves the U(1) problem and helps produce a light pion. We use the ensuing light front wavefunctions, to derive the pertinent parton distribution functions, parton amplitudes and low energy constants.
[ { "created": "Fri, 31 Dec 2021 18:45:58 GMT", "version": "v1" }, { "created": "Wed, 10 Aug 2022 14:29:47 GMT", "version": "v2" } ]
2022-08-11
[ [ "Shuryak", "Edward", "" ], [ "Zahed", "Ismail", "" ] ]
This is the third paper on hadronic light front wave functions (LFWFs). We derive a light front Hamiltonian from first principles using the key features of the QCD vacuum at low resolution. In the first approximation, it gives transverse oscillator and longitudinal harmonic modes and yields the correct Regge trajectories. For heavy quarkonia, we compare its spectrum to that obtained from the usual Schroedinger equation in the rest frame. We use the same approach for light quarks, and investigate the role of confinement and chiral symmetry breaking in the quark-antiquark sector. We then study spin-spin and spin-orbit mixing, resulting in e.g. quadrupole moments of vector mesons. For the light mesons, we show how to extend the famed t$^\prime$Hooft interaction to the light front, which solves the U(1) problem and helps produce a light pion. We use the ensuing light front wavefunctions, to derive the pertinent parton distribution functions, parton amplitudes and low energy constants.
1507.02271
Yu Gao
Rouzbeh Allahverdi, Mykhailo Dalchenko, Bhaskar Dutta, Andr\'es Fl\'orez, Yu Gao, Teruki Kamon, Nikolay Kolev, Ryan Mueller and Manuel Segura
Distinguishing Standard Model Extensions using Monotop Chirality at the LHC
7 pages, 7 figures, 3 tables. New authors added; Standard model background analysis and model discrimination prospects included
null
10.1007/JHEP12(2016)046
MI-TH-1523, CETUP2015-011
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present two minimal extensions of the standard model, each giving rise to baryogenesis. They include heavy color-triplet scalars interacting with a light Majorana fermion that can be the dark matter (DM) candidate. The electroweak charges of the new scalars govern their couplings to quarks of different chirality, which leads to different collider signals. These models predict monotop events at the LHC and the energy spectrum of decay products of highly polarized top quarks can be used to establish the chiral nature of the interactions involving the heavy scalars and the DM. Detailed simulation of signal and standard model background events is performed, showing that top quark chirality can be distinguished in hadronic and leptonic decays of the top quarks.
[ { "created": "Wed, 8 Jul 2015 19:54:23 GMT", "version": "v1" }, { "created": "Thu, 7 Jan 2016 01:42:52 GMT", "version": "v2" }, { "created": "Tue, 29 Nov 2016 21:14:46 GMT", "version": "v3" } ]
2017-02-01
[ [ "Allahverdi", "Rouzbeh", "" ], [ "Dalchenko", "Mykhailo", "" ], [ "Dutta", "Bhaskar", "" ], [ "Flórez", "Andrés", "" ], [ "Gao", "Yu", "" ], [ "Kamon", "Teruki", "" ], [ "Kolev", "Nikolay", "" ], [ "Mueller", "Ryan", "" ], [ "Segura", "Manuel", "" ] ]
We present two minimal extensions of the standard model, each giving rise to baryogenesis. They include heavy color-triplet scalars interacting with a light Majorana fermion that can be the dark matter (DM) candidate. The electroweak charges of the new scalars govern their couplings to quarks of different chirality, which leads to different collider signals. These models predict monotop events at the LHC and the energy spectrum of decay products of highly polarized top quarks can be used to establish the chiral nature of the interactions involving the heavy scalars and the DM. Detailed simulation of signal and standard model background events is performed, showing that top quark chirality can be distinguished in hadronic and leptonic decays of the top quarks.
hep-ph/9701269
null
Vadim A. Kuzmin
A Simultaneous Solution to Baryogenesis and Dark Matter Problems
Latex file. Talk at Workshop on 'Aspects of Dark Matter in Astro- and Particle Physics', Heidelberg, Germany, September 16-20, 1996; to be published in Proc. of Workshop by World-Scientific, Singapore, 1997
Phys.Part.Nucl.29:257-265,1998; Fiz.Elem.Chast.Atom.Yadra 29:637-658,1998
10.1134/1.953070
null
hep-ph
null
A new concept of generation of the cosmological baryon excess along with the cold dark matter (CDM) in the Universe is proposed and corresponding scenarios are outlined. Possible realizations of the idea in the framework of supersymmetric models are considered and constraints (predictions) on masses of sparticles compatible with the viability of the scenario are derived. Mulitiple predictions might be extracted from the concept. In particular, we predict a quite natural existence of a charge asymmetric component of CDM. A $\sim 10^{-2}$ part of CDM might exist in the form of electrically charged relic particles with masses $m \simeq 1$ TeV. They are negatively charged and are dresses by protons. This conjecture provides a rich field of immediate search for these particles. The charge symmetric component of CDM might be represented by very light, $m \approx 2$ GeV, very weakly interacting particles like right-handed sneutrinos ( so recoils expected are rare and have quite small energies, $E_{recoil} \sim 1$ KeV.) This leads by the way to prediction of long-living (charged) sparticles. Some new experimental proposals for non-traditional search of cold dark matter particles are mentioned.
[ { "created": "Sun, 12 Jan 1997 00:05:27 GMT", "version": "v1" } ]
2014-11-17
[ [ "Kuzmin", "Vadim A.", "" ] ]
A new concept of generation of the cosmological baryon excess along with the cold dark matter (CDM) in the Universe is proposed and corresponding scenarios are outlined. Possible realizations of the idea in the framework of supersymmetric models are considered and constraints (predictions) on masses of sparticles compatible with the viability of the scenario are derived. Mulitiple predictions might be extracted from the concept. In particular, we predict a quite natural existence of a charge asymmetric component of CDM. A $\sim 10^{-2}$ part of CDM might exist in the form of electrically charged relic particles with masses $m \simeq 1$ TeV. They are negatively charged and are dresses by protons. This conjecture provides a rich field of immediate search for these particles. The charge symmetric component of CDM might be represented by very light, $m \approx 2$ GeV, very weakly interacting particles like right-handed sneutrinos ( so recoils expected are rare and have quite small energies, $E_{recoil} \sim 1$ KeV.) This leads by the way to prediction of long-living (charged) sparticles. Some new experimental proposals for non-traditional search of cold dark matter particles are mentioned.
hep-ph/9311237
null
B.Z.Kopeliovich, J.Nemchick, N.N.Nikolaev and and B.G.Zakharov
Decisive test of color transparency in exclusive electroproduction of vector mesons
11 pages, 4 figures on the request from kph154@zam001.zam.kfa-juelich.de, Juelich preprint KFA-IKP(Th)-1993-27. \phantom{.}\hspace{9cm}{\sl 8 November 1993}
Phys.Lett.B324:469-476,1994
10.1016/0370-2693(94)90225-9
null
hep-ph nucl-th
null
The exclusive production of vector mesons in deep inelastic scattering is a hard scattering process with the well controlled size of quark configurations which dominate the production amplitude. This allows an unambiguous prediction of color transparency effects in the coherent and incoherent production of vector mesons on nuclei. We demonstrate how the very mechanism of color transparency leads to a belated onset of color transparency effects as a function of $Q^{2}$. We conclude that the $Q^{2}$ dependence of the exclusive $\rho^{0}$-meson production on nuclei and nucleons observed in the Fermilab E665 experiment gives a solid evidence for the onset of color transparency. We propose the scaling relation between the $\rho^{0}$ and the $J/\Psi$ production, which further tests the mechanism of color transparency in exclusive (virtual) photoproduction.
[ { "created": "Mon, 8 Nov 1993 15:38:56 GMT", "version": "v1" } ]
2012-08-27
[ [ "Kopeliovich", "B. Z.", "" ], [ "Nemchick", "J.", "" ], [ "Nikolaev", "N. N.", "" ], [ "Zakharov", "and B. G.", "" ] ]
The exclusive production of vector mesons in deep inelastic scattering is a hard scattering process with the well controlled size of quark configurations which dominate the production amplitude. This allows an unambiguous prediction of color transparency effects in the coherent and incoherent production of vector mesons on nuclei. We demonstrate how the very mechanism of color transparency leads to a belated onset of color transparency effects as a function of $Q^{2}$. We conclude that the $Q^{2}$ dependence of the exclusive $\rho^{0}$-meson production on nuclei and nucleons observed in the Fermilab E665 experiment gives a solid evidence for the onset of color transparency. We propose the scaling relation between the $\rho^{0}$ and the $J/\Psi$ production, which further tests the mechanism of color transparency in exclusive (virtual) photoproduction.
2303.14764
Xiangwei Yin
Wenxing Zhang, Tianjun Li, Xiangwei Yin
The $Z$ resonance, inelastic dark matter, and new physics anomalies in the Simple Extension of the Standard Model (SESM) with general scalar potential
22 pages, 6 figures, 5 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the generic scalar potential with CP-violation, and study the $Z$ resonance and inelastic dark matter in the Simple Extension of the Standard Model (SESM), which can explain the dark matter as well as new physics anomalies such as the B physics anomalies and muon anomalous magnetic moment, etc. With the new scalar potential terms, we obtain the mass splittings for the real and imaginary parts of scalar fields. And thus we can have the DM co-annihilation process mediated by $Z$ boson, which couples exclusively to the CP-even and CP-odd parts of scalar fields. This is a brand new feature compared to the previous study. For the CP conserving case, we present the viable parameter space for the Higgs and $Z$ resonances, which can explain the B physics anomalies, muon anomalous magnetic moment, and dark matter relic density, as well as evade the constraint from the XENON1T direct detection simultaneously. For the CP-violating case, we consider the inelastic dark matter, and study four concrete scenarios for the inelastic DM-nucleon scatterings mediated by the Higgs and $Z$ bosons in details. Also, we present the benchmark points which satisfy the aforementioned constraints. Furthermore, we investigate the constraints from the dark matter-electron inelastic scattering processes mediated by the Higgs and $Z$ bosons in light of the XENONnT data. We show that the constraint on the $Z$ mediated process is weak, while the Higgs mediated process excludes the dark matter with mass around several MeV.
[ { "created": "Sun, 26 Mar 2023 15:56:02 GMT", "version": "v1" }, { "created": "Thu, 5 Oct 2023 16:31:35 GMT", "version": "v2" } ]
2023-10-06
[ [ "Zhang", "Wenxing", "" ], [ "Li", "Tianjun", "" ], [ "Yin", "Xiangwei", "" ] ]
We consider the generic scalar potential with CP-violation, and study the $Z$ resonance and inelastic dark matter in the Simple Extension of the Standard Model (SESM), which can explain the dark matter as well as new physics anomalies such as the B physics anomalies and muon anomalous magnetic moment, etc. With the new scalar potential terms, we obtain the mass splittings for the real and imaginary parts of scalar fields. And thus we can have the DM co-annihilation process mediated by $Z$ boson, which couples exclusively to the CP-even and CP-odd parts of scalar fields. This is a brand new feature compared to the previous study. For the CP conserving case, we present the viable parameter space for the Higgs and $Z$ resonances, which can explain the B physics anomalies, muon anomalous magnetic moment, and dark matter relic density, as well as evade the constraint from the XENON1T direct detection simultaneously. For the CP-violating case, we consider the inelastic dark matter, and study four concrete scenarios for the inelastic DM-nucleon scatterings mediated by the Higgs and $Z$ bosons in details. Also, we present the benchmark points which satisfy the aforementioned constraints. Furthermore, we investigate the constraints from the dark matter-electron inelastic scattering processes mediated by the Higgs and $Z$ bosons in light of the XENONnT data. We show that the constraint on the $Z$ mediated process is weak, while the Higgs mediated process excludes the dark matter with mass around several MeV.
0811.0953
Peihong Gu
Pei-Hong Gu, M. Hirsch, Utpal Sarkar, J.W.F. Valle
Neutrino masses, leptogenesis and dark matter in hybrid seesaw
4 pages
Phys.Rev.D79:033010,2009
10.1103/PhysRevD.79.033010
IFIC/08-60
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We suggest a hybrid seesaw model where relatively ``light''right-handed neutrinos give no contribution to the neutrino mass matrix due to a special symmetry. This allows their Yukawa couplings to the standard model particles to be relatively strong, so that the standard model Higgs boson can decay dominantly to a left and a right-handed neutrino, leaving another stable right-handed neutrino as cold dark matter. In our model neutrino masses arise via the type-II seesaw mechanism, the Higgs triplet scalars being also responsible for the generation of the matter-antimatter asymmetry via the leptogenesis mechanism.
[ { "created": "Thu, 6 Nov 2008 15:36:32 GMT", "version": "v1" } ]
2009-04-29
[ [ "Gu", "Pei-Hong", "" ], [ "Hirsch", "M.", "" ], [ "Sarkar", "Utpal", "" ], [ "Valle", "J. W. F.", "" ] ]
We suggest a hybrid seesaw model where relatively ``light''right-handed neutrinos give no contribution to the neutrino mass matrix due to a special symmetry. This allows their Yukawa couplings to the standard model particles to be relatively strong, so that the standard model Higgs boson can decay dominantly to a left and a right-handed neutrino, leaving another stable right-handed neutrino as cold dark matter. In our model neutrino masses arise via the type-II seesaw mechanism, the Higgs triplet scalars being also responsible for the generation of the matter-antimatter asymmetry via the leptogenesis mechanism.
hep-ph/9502230
Morgan
A.G. Morgan
Second Order Fermions in Gauge Theories
13 Pages LaTeX with 4 PostScript figures attached (figures may be included with epsfig.sty). Complete paper may be found at http://newton.physics.ucla.edu:80/~morgan/2nd.html
Phys.Lett. B351 (1995) 249-256
10.1016/0370-2693(95)00377-W
UCLA/95/TEP/3
hep-ph
null
The second order formalism for fermions provides a description of fermions that is very similar to that of scalars. We demonstrate that this second order formalism is equivalent to the standard Dirac formalism. We do so in terms of the conventional fermionic Feynman rules. The second order formalism has previously proven useful for the computation of fermion loops, here we describe how the corresponding rules can be applied to the calculation of amplitudes involving external fermions, including tree-level processes and processes with more than one fermion line. We comment on the supersymmetric identities relating fermions and scalars and the associated simplifications to perturbative calculations that are then more transparent.
[ { "created": "Mon, 6 Feb 1995 04:35:36 GMT", "version": "v1" } ]
2016-09-01
[ [ "Morgan", "A. G.", "" ] ]
The second order formalism for fermions provides a description of fermions that is very similar to that of scalars. We demonstrate that this second order formalism is equivalent to the standard Dirac formalism. We do so in terms of the conventional fermionic Feynman rules. The second order formalism has previously proven useful for the computation of fermion loops, here we describe how the corresponding rules can be applied to the calculation of amplitudes involving external fermions, including tree-level processes and processes with more than one fermion line. We comment on the supersymmetric identities relating fermions and scalars and the associated simplifications to perturbative calculations that are then more transparent.
2407.05298
Tianhong Wang
Gang Yang, Tianhong Wang, and Guo-Li Wang
Probing axion-like particles in leptonic decays of heavy mesons
17 pages, 23 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the possibility to find the axion-like particles (ALPs) through the leptonic decays of heavy mesons. There are some deviations between the Standard Model (SM) predictions of the branching ratios of the leptonic decays of mesons and the experimental data. This provides some space for the existence of decay channels where the ALP is one of the products. Three scenarios are considered: first, the ALP is only coupled to one single charged fermion, namely, the quark, the antiquark, or the charged lepton; second, the ALP is only coupled to quark and antiquark with the same strength; third, the ALP is coupled to all the charged fermions with the same strength. The constraints of the coupling strength in different scenarios are obtained by comparing the experimental data of the branching ratios of leptonic decays of $B^-$, $D^+$, and $D_s^+$ mesons with the theoretical predictions which are achieved by using the Bethe-Salpeter (BS) method. These constraints are further applied to predict the upper limits of the leptonic decay processes of the $B_c^-$ meson in which the ALP participates.
[ { "created": "Sun, 7 Jul 2024 07:48:50 GMT", "version": "v1" } ]
2024-07-09
[ [ "Yang", "Gang", "" ], [ "Wang", "Tianhong", "" ], [ "Wang", "Guo-Li", "" ] ]
We study the possibility to find the axion-like particles (ALPs) through the leptonic decays of heavy mesons. There are some deviations between the Standard Model (SM) predictions of the branching ratios of the leptonic decays of mesons and the experimental data. This provides some space for the existence of decay channels where the ALP is one of the products. Three scenarios are considered: first, the ALP is only coupled to one single charged fermion, namely, the quark, the antiquark, or the charged lepton; second, the ALP is only coupled to quark and antiquark with the same strength; third, the ALP is coupled to all the charged fermions with the same strength. The constraints of the coupling strength in different scenarios are obtained by comparing the experimental data of the branching ratios of leptonic decays of $B^-$, $D^+$, and $D_s^+$ mesons with the theoretical predictions which are achieved by using the Bethe-Salpeter (BS) method. These constraints are further applied to predict the upper limits of the leptonic decay processes of the $B_c^-$ meson in which the ALP participates.
2305.11538
Xing-Hua Yang
Xing-Hua Yang, Fei Huang, Ji Xu
Nuclear effects in extracting $\sin^2\theta_W$ and a probe for short-range correlations
8 pages, 7 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We investigate the neutral-current neutrino-nucleon deep inelastic scattering with particular emphasis on short-range correlation and EMC effect, as well as their impact on the weak-mixing angle $\sin^2\theta_W$ determination. The ratios of structure function $F_{2(NC)}^{A}$ and $x F_{3(NC)}^{A}$ are presented where the nuclei $A$ are chosen as carbon, iron and lead. One kind of universal modification function is proposed which would provide a nontrivial test of SRC universality on the platform of neutrino-nucleon DIS. In addition, we study the impact of ``SRC-driven'' nuclear effects on the extraction of $\sin^2\theta_W$ which is naturally associated with the renowned NuTeV anomaly. The results indicate that these effects may account for a substantial fraction of the NuTeV anomaly and considerably affect the value of extracted $\sin^2\theta_W$.
[ { "created": "Fri, 19 May 2023 09:15:50 GMT", "version": "v1" }, { "created": "Fri, 26 May 2023 07:27:52 GMT", "version": "v2" } ]
2023-05-29
[ [ "Yang", "Xing-Hua", "" ], [ "Huang", "Fei", "" ], [ "Xu", "Ji", "" ] ]
We investigate the neutral-current neutrino-nucleon deep inelastic scattering with particular emphasis on short-range correlation and EMC effect, as well as their impact on the weak-mixing angle $\sin^2\theta_W$ determination. The ratios of structure function $F_{2(NC)}^{A}$ and $x F_{3(NC)}^{A}$ are presented where the nuclei $A$ are chosen as carbon, iron and lead. One kind of universal modification function is proposed which would provide a nontrivial test of SRC universality on the platform of neutrino-nucleon DIS. In addition, we study the impact of ``SRC-driven'' nuclear effects on the extraction of $\sin^2\theta_W$ which is naturally associated with the renowned NuTeV anomaly. The results indicate that these effects may account for a substantial fraction of the NuTeV anomaly and considerably affect the value of extracted $\sin^2\theta_W$.
hep-ph/0504038
Liliana Velasco-Sevilla
G. L. Kane (1), S. F. King (2), I. N. R. Peddie (2) and L. Velasco-Sevilla (1) ((1) Michigan Center for theoretical Physics, (2) School of Phys. and Astronomy, Univ. of Southampton)
Study of theory and phenomenology of some classes of family symmetry and unification models
75 pages, 4 figures
JHEP0508:083,2005
10.1088/1126-6708/2005/08/083
SHEP-05-12, MCTP-05-70
hep-ph
null
We review and compare theoretically and phenomenologically a number of possible family symmetries, which when combined with unification, could be important in explaining quark, lepton and neutrino masses and mixings, providing new results in several cases. Theoretical possibilities include Abelian or non-Abelian, symmetric or non symmetric Yukawa matrices, Grand Unification or not. Our main focus is on anomaly-free U(1) family symmetry combined with SU(5) unification, although we also discuss other possibilities. We provide a detailed phenomenological fit of the fermion masses and mixings for several examples, and discuss the supersymmetric flavour issues in such theories, including a detailed analysis of lepton flavour violation. We show that it is not possible to quantitatively and decisively discriminate between these different theoretical possibilities at the present time.
[ { "created": "Wed, 6 Apr 2005 17:13:39 GMT", "version": "v1" } ]
2009-11-11
[ [ "Kane", "G. L.", "" ], [ "King", "S. F.", "" ], [ "Peddie", "I. N. R.", "" ], [ "Velasco-Sevilla", "L.", "" ] ]
We review and compare theoretically and phenomenologically a number of possible family symmetries, which when combined with unification, could be important in explaining quark, lepton and neutrino masses and mixings, providing new results in several cases. Theoretical possibilities include Abelian or non-Abelian, symmetric or non symmetric Yukawa matrices, Grand Unification or not. Our main focus is on anomaly-free U(1) family symmetry combined with SU(5) unification, although we also discuss other possibilities. We provide a detailed phenomenological fit of the fermion masses and mixings for several examples, and discuss the supersymmetric flavour issues in such theories, including a detailed analysis of lepton flavour violation. We show that it is not possible to quantitatively and decisively discriminate between these different theoretical possibilities at the present time.
hep-ph/0306100
Sheldon Lee Glashow
Sheldon Lee Glashow
Fact and Fancy in Neutrino Physics II
7 pages
null
null
null
hep-ph
null
This brief and opinionated essay evolved from my closing talk at the Tenth International Workshop on Neutrino Telescopes, held in Venice in March 2003. Portions were inspired by several excellent presentations at the Workshop. Other scattered comments about neutrino physics relate to variations of the seesaw model yielding the FGY ansatz, or to those yielding significant suppressive mixing of neutrino amplitudes.
[ { "created": "Wed, 11 Jun 2003 21:00:47 GMT", "version": "v1" } ]
2016-09-06
[ [ "Glashow", "Sheldon Lee", "" ] ]
This brief and opinionated essay evolved from my closing talk at the Tenth International Workshop on Neutrino Telescopes, held in Venice in March 2003. Portions were inspired by several excellent presentations at the Workshop. Other scattered comments about neutrino physics relate to variations of the seesaw model yielding the FGY ansatz, or to those yielding significant suppressive mixing of neutrino amplitudes.
1907.00176
Olga I. Piskounova
Olga I. Piskounova and Konstantine A. Kotelnikov
HE Stratosphere Event of 1975 Revisited: the Difference between the Patterns of Astroparticle Interaction and LHC Nucleus-Nucleus Collision
10 pages, 8 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The event of astroparticle collision at high energy was detected in 1975 during the balloon flight in the stratosphere. The data of hundred particle tracks in x-ray films have been re-analyzed in the style of LHC experiments: rapidity distributions of charged particles and transverse mass spectra of multi-particle production have been built. The comparison of multiple histograms with the expectations of the Quark-Gluon String Model (QGSM) gives us, at first sight, the conclusion that it might be the carbon-nucleus collision with the matter of atmosphere at the c.m.s. equivalent energy $\sqrt{s} \ge $ 5 TeV. Nevertheless, the data indicate the features that cannot be associated with nucleus-nucleus collision: one particle with transverse mass 16 GeV was detected and a small nucleon population has been seen in the region of projectile fragmentation that does not correspond to the carbon nucleus collision. Both facts make us convinced that there might be a baryonic DM decay (Piskounova O., 2018). Baryonic DM particles are to be formed at the huge gravitation pressure in giant massive objects like Black Holes. Relativistic jets are spreading the baryonic DM in space. The important difference between this form of matter and the ordinary nucleus lies in the results of collision: baryonic DM is the object, where protons and antiprotons are strongly connected, so the energy is divided between nucleon components due to the structure function of Regge type, like for quarks in the proton. The lightest debris of baryonic DM particle interacts with the greatest maximal rapidity and gives the small number of nucleons in the forwarding part of spectra. Baryonic DM can also split into the pair of similar DM with lower mass giving an unusual couple of hadrons with mass like 14 GeV and heavier.
[ { "created": "Sat, 29 Jun 2019 10:05:00 GMT", "version": "v1" }, { "created": "Wed, 2 Feb 2022 13:54:53 GMT", "version": "v10" }, { "created": "Sat, 12 Mar 2022 15:19:33 GMT", "version": "v11" }, { "created": "Tue, 15 Mar 2022 07:42:53 GMT", "version": "v12" }, { "created": "Sat, 6 Jul 2019 06:32:20 GMT", "version": "v2" }, { "created": "Wed, 10 Jul 2019 05:39:29 GMT", "version": "v3" }, { "created": "Sun, 25 Aug 2019 06:02:33 GMT", "version": "v4" }, { "created": "Tue, 8 Oct 2019 10:18:13 GMT", "version": "v5" }, { "created": "Thu, 10 Oct 2019 11:02:41 GMT", "version": "v6" }, { "created": "Thu, 30 Jul 2020 16:47:03 GMT", "version": "v7" }, { "created": "Mon, 9 Aug 2021 07:04:34 GMT", "version": "v8" }, { "created": "Mon, 17 Jan 2022 15:20:56 GMT", "version": "v9" } ]
2022-03-17
[ [ "Piskounova", "Olga I.", "" ], [ "Kotelnikov", "Konstantine A.", "" ] ]
The event of astroparticle collision at high energy was detected in 1975 during the balloon flight in the stratosphere. The data of hundred particle tracks in x-ray films have been re-analyzed in the style of LHC experiments: rapidity distributions of charged particles and transverse mass spectra of multi-particle production have been built. The comparison of multiple histograms with the expectations of the Quark-Gluon String Model (QGSM) gives us, at first sight, the conclusion that it might be the carbon-nucleus collision with the matter of atmosphere at the c.m.s. equivalent energy $\sqrt{s} \ge $ 5 TeV. Nevertheless, the data indicate the features that cannot be associated with nucleus-nucleus collision: one particle with transverse mass 16 GeV was detected and a small nucleon population has been seen in the region of projectile fragmentation that does not correspond to the carbon nucleus collision. Both facts make us convinced that there might be a baryonic DM decay (Piskounova O., 2018). Baryonic DM particles are to be formed at the huge gravitation pressure in giant massive objects like Black Holes. Relativistic jets are spreading the baryonic DM in space. The important difference between this form of matter and the ordinary nucleus lies in the results of collision: baryonic DM is the object, where protons and antiprotons are strongly connected, so the energy is divided between nucleon components due to the structure function of Regge type, like for quarks in the proton. The lightest debris of baryonic DM particle interacts with the greatest maximal rapidity and gives the small number of nucleons in the forwarding part of spectra. Baryonic DM can also split into the pair of similar DM with lower mass giving an unusual couple of hadrons with mass like 14 GeV and heavier.
hep-ph/9708424
Carlo Ewerz
Vladimir Gribov
QCD at large and short distances
39 pages, Latex, 115 figures included using epsfig.sty
null
null
Bonn TK 97-08
hep-ph
null
The formulation of QCD which contains no divergences and no renormalization procedure is presented. It contains both perturbative and non-perturbative phenomena. It is shown that, due to its asymptotically free nature, the theory is not defined uniquely. The chiral symmetry breaking and the nature of the octet of pseudo-scalar particles as quasi-Goldstone states are analysed in the theory with massless and massive quarks. The U(1) problem is discussed.
[ { "created": "Thu, 21 Aug 1997 13:31:52 GMT", "version": "v1" } ]
2007-05-23
[ [ "Gribov", "Vladimir", "" ] ]
The formulation of QCD which contains no divergences and no renormalization procedure is presented. It contains both perturbative and non-perturbative phenomena. It is shown that, due to its asymptotically free nature, the theory is not defined uniquely. The chiral symmetry breaking and the nature of the octet of pseudo-scalar particles as quasi-Goldstone states are analysed in the theory with massless and massive quarks. The U(1) problem is discussed.
hep-ph/0001252
Olga
O.I.Piskounova (P.N.Lebedev Physical Institute, Moscow, Russia)
B-meson hadroproduction cross sections and up-to-date models
LateX, pages, 4 epsfigures, some ideas of this paper were already published in the last millenium, Proceed. of 'Heavy Quarks', Rostock,1998
Phys.Atom.Nucl.64:392,2001
null
null
hep-ph
null
The comparison of B-meson production cross sections as the results of PYTHIA code and Quark Gluon String Model (QGSM) is carried out for energies of proton colliders: $Sp\bar(p)S$, Tevatron and LHC. Model predictions are based on the theory of supercritical Pomeron exchanges with the phenomenological intercept $\Delta_P$(0)=0.3, accepted for heavy quark production.Transverse momentum spectra of B-mesons are also compared. It is shown that the cross sections calculated with PYTHIA using CTEQ structure functions are in a contradiction with the asymptotical estimation of B$\bar{B}$ production cross sections in QGSM. Asymmetries between the spectra of $B^0$ and $\bar{B0}$ mesons are also contradicting. The reasons of the difference are discussed.
[ { "created": "Tue, 25 Jan 2000 09:55:08 GMT", "version": "v1" }, { "created": "Wed, 26 Jan 2000 09:23:33 GMT", "version": "v2" } ]
2011-03-23
[ [ "Piskounova", "O. I.", "", "P.N.Lebedev Physical Institute, Moscow, Russia" ] ]
The comparison of B-meson production cross sections as the results of PYTHIA code and Quark Gluon String Model (QGSM) is carried out for energies of proton colliders: $Sp\bar(p)S$, Tevatron and LHC. Model predictions are based on the theory of supercritical Pomeron exchanges with the phenomenological intercept $\Delta_P$(0)=0.3, accepted for heavy quark production.Transverse momentum spectra of B-mesons are also compared. It is shown that the cross sections calculated with PYTHIA using CTEQ structure functions are in a contradiction with the asymptotical estimation of B$\bar{B}$ production cross sections in QGSM. Asymmetries between the spectra of $B^0$ and $\bar{B0}$ mesons are also contradicting. The reasons of the difference are discussed.
hep-ph/9401322
Jacques Goldberg
Jacques Goldberg
What is the statistical significance of the solar neutrino flux problem?
8 pages, TECHNION-PH-94-2
null
null
null
hep-ph
null
Uniform random numbers, not Gaussian random numbers, should have been used with Standard Solar Models to estimate the effect on the neutrino flux of uncertainties in input data. The observed discrepancy is therefore probably quite smaller than currently accepted.
[ { "created": "Tue, 25 Jan 1994 11:10:12 GMT", "version": "v1" } ]
2007-05-23
[ [ "Goldberg", "Jacques", "" ] ]
Uniform random numbers, not Gaussian random numbers, should have been used with Standard Solar Models to estimate the effect on the neutrino flux of uncertainties in input data. The observed discrepancy is therefore probably quite smaller than currently accepted.
hep-ph/0506053
Christian Fischer
C. S. Fischer, B. Gruter and R. Alkofer
Solving coupled Dyson--Schwinger equations on a compact manifold
26 pages, 13 figures; v2: sections rearranged, refs updated, version to be published in Annals of Physics
Ann.Phys.321:1918-1938,2006
10.1016/j.aop.2005.11.007
IPPP/05/16, DCPT/05/32
hep-ph hep-lat hep-th
null
We present results for the gluon and ghost propagators in SU(N) Yang--Mills theory on a four-torus at zero and nonzero temperatures from a truncated set of Dyson-Schwinger equations. When compared to continuum solutions at zero temperature sizeable modifications due to the finite volume of the manifold, especially in the infrared, are found. Effects due to non-vanishing temperatures T, on the other hand, are minute for T < 250 MeV.
[ { "created": "Mon, 6 Jun 2005 15:14:29 GMT", "version": "v1" }, { "created": "Mon, 14 Nov 2005 17:20:54 GMT", "version": "v2" } ]
2008-11-26
[ [ "Fischer", "C. S.", "" ], [ "Gruter", "B.", "" ], [ "Alkofer", "R.", "" ] ]
We present results for the gluon and ghost propagators in SU(N) Yang--Mills theory on a four-torus at zero and nonzero temperatures from a truncated set of Dyson-Schwinger equations. When compared to continuum solutions at zero temperature sizeable modifications due to the finite volume of the manifold, especially in the infrared, are found. Effects due to non-vanishing temperatures T, on the other hand, are minute for T < 250 MeV.
hep-ph/9809268
Carsten Greiner
Carsten Greiner
Physics of Strange Matter
13 pages, 6 eps-figures, 1 gif-figure, Invited talk at the IV International Conference on 'Strangeness in Quark Matter', Padova (Italy), July 20 - 24, 1998
J.Phys.G25:389-401,1999
10.1088/0954-3899/25/2/028
UGI-98-26
hep-ph nucl-th
null
Relativistic heavy ion collisions offer the possibility to produce exotic metastable states of nuclear matter containing (roughly) equal number of strangeness compared to the content in baryon number. The reasoning of both their stability and existence, the possible distillation of strangeness necessary for their formation and the chances for their detection are reviewed. In the later respect emphasize is put on the properties of small lumps of strange quark matter with respect to their stability against strong or weak hadronic decays. In addition, implications in astrophysics like the properties of neutron stars and the issue of baryonic dark matter will be discussed.
[ { "created": "Fri, 4 Sep 1998 14:27:33 GMT", "version": "v1" } ]
2008-11-26
[ [ "Greiner", "Carsten", "" ] ]
Relativistic heavy ion collisions offer the possibility to produce exotic metastable states of nuclear matter containing (roughly) equal number of strangeness compared to the content in baryon number. The reasoning of both their stability and existence, the possible distillation of strangeness necessary for their formation and the chances for their detection are reviewed. In the later respect emphasize is put on the properties of small lumps of strange quark matter with respect to their stability against strong or weak hadronic decays. In addition, implications in astrophysics like the properties of neutron stars and the issue of baryonic dark matter will be discussed.
1205.2096
S. Weinzierl
Sebastian Becker, Christian Reuschle and Stefan Weinzierl
Efficiency improvements for the numerical computation of NLO corrections
34 pages, version to be published
null
10.1007/JHEP07(2012)090
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we discuss techniques, which lead to a significant improvement of the efficiency of the Monte Carlo integration, when one-loop QCD amplitudes are calculated numerically with the help of the subtraction method and contour deformation. The techniques discussed are: holomorphic and non-holomorphic division into sub-channels, optimisation of the integration contour, improvement of the ultraviolet subtraction terms, importance sampling and antithetic variates in loop momentum space, recurrence relations.
[ { "created": "Wed, 9 May 2012 20:10:54 GMT", "version": "v1" }, { "created": "Mon, 25 Jun 2012 08:29:25 GMT", "version": "v2" } ]
2015-06-05
[ [ "Becker", "Sebastian", "" ], [ "Reuschle", "Christian", "" ], [ "Weinzierl", "Stefan", "" ] ]
In this paper we discuss techniques, which lead to a significant improvement of the efficiency of the Monte Carlo integration, when one-loop QCD amplitudes are calculated numerically with the help of the subtraction method and contour deformation. The techniques discussed are: holomorphic and non-holomorphic division into sub-channels, optimisation of the integration contour, improvement of the ultraviolet subtraction terms, importance sampling and antithetic variates in loop momentum space, recurrence relations.
0710.1878
Marina Nielsen
M.E. Bracco, M. Chiapparini, F.S. Navarra and M. Nielsen
\rho D^*D^* vertex from QCD sum rules
9 pages, 6 eps figures
Phys.Lett.B659:559-564,2008
10.1016/j.physletb.2007.11.066
null
hep-ph
null
We calculate the form factors and the coupling constant in the $\rho D^* D^*$ vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both $\rho$ and $D^*$ mesons off--shell. The form factors obtained are very different but give the same coupling constant: $g_{\rho D^* D^*} = 6.6 \pm 0.31$. This number is 50% larger than what we would expect from SU(4) estimates.
[ { "created": "Tue, 9 Oct 2007 21:06:02 GMT", "version": "v1" } ]
2008-11-26
[ [ "Bracco", "M. E.", "" ], [ "Chiapparini", "M.", "" ], [ "Navarra", "F. S.", "" ], [ "Nielsen", "M.", "" ] ]
We calculate the form factors and the coupling constant in the $\rho D^* D^*$ vertex in the framework of QCD sum rules. We evaluate the three point correlation functions of the vertex considering both $\rho$ and $D^*$ mesons off--shell. The form factors obtained are very different but give the same coupling constant: $g_{\rho D^* D^*} = 6.6 \pm 0.31$. This number is 50% larger than what we would expect from SU(4) estimates.
hep-ph/0501119
Igor Anikin
I.V. Anikin, B. Pire, L. Szymanowski, O.V. Teryaev, S. Wallon
$\pi\eta$ pair hard electroproduction and exotic hybrid mesons
4 pages, 1 figure, presented by I.V. Anikin at Xth International Conference "BARYONS'04", Palaiseau, France
Nucl.Phys. A755 (2005) 561-564
10.1016/j.nuclphysa.2005.03.156
null
hep-ph
null
We show that hard electroproduction is a promising way to study exotic hybrid mesons, in particular through the hybrid decay channel $H \to \pi\eta $. We discuss the $\pi\eta$ generalized distribution amplitude, calculate the production amplitude and propose a forward-backward asymmetry as a signal for the hybrid meson production.
[ { "created": "Fri, 14 Jan 2005 09:41:02 GMT", "version": "v1" } ]
2009-11-11
[ [ "Anikin", "I. V.", "" ], [ "Pire", "B.", "" ], [ "Szymanowski", "L.", "" ], [ "Teryaev", "O. V.", "" ], [ "Wallon", "S.", "" ] ]
We show that hard electroproduction is a promising way to study exotic hybrid mesons, in particular through the hybrid decay channel $H \to \pi\eta $. We discuss the $\pi\eta$ generalized distribution amplitude, calculate the production amplitude and propose a forward-backward asymmetry as a signal for the hybrid meson production.
1012.4699
Raju Venugopalan
Raju Venugopalan (BNL)
From many body wee parton dynamics to perfect fluid: a standard model for heavy ion collisions
Extended version of Plenary Talk at the 35th International Conference on High Energy Physics (ICHEP2010), Paris, France, July 22-28, 2010. 14 pages, 9 figures
null
null
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss a standard model of heavy ion collisions that has emerged both from the experimental results of the RHIC program and associated theoretical developments. We comment briefly on the impact of early results of the LHC program on this picture. We consider how this standard model of heavy ion collisions could be solidified or falsified in future experiments at RHIC, the LHC and a future Electron-Ion Collider.
[ { "created": "Tue, 21 Dec 2010 15:46:43 GMT", "version": "v1" }, { "created": "Fri, 24 Dec 2010 04:53:53 GMT", "version": "v2" } ]
2010-12-27
[ [ "Venugopalan", "Raju", "", "BNL" ] ]
We discuss a standard model of heavy ion collisions that has emerged both from the experimental results of the RHIC program and associated theoretical developments. We comment briefly on the impact of early results of the LHC program on this picture. We consider how this standard model of heavy ion collisions could be solidified or falsified in future experiments at RHIC, the LHC and a future Electron-Ion Collider.
2004.07841
Jianlong Lu
Jianlong Lu
Neutrino Masses and Noncyclic Geometric Phase of Entangled Charged Lepton-Neutrino Pair in External Magnetic Field
5 pages, 0 figure
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we consider a pair of entangled charged lepton-neutrino embedded in a constant magnetic field, which can be produced in the purely leptonic decay of charged pseudoscalar mesons. Particles with nonzero magnetic dipole moment will precess in the present of external magnetic field and induce a nontrivial noncyclic geometric phase. The dependence of this geometric phase on neutrino mass can be used to determine the Dirac/Majorana nature of massive neutrinos.
[ { "created": "Thu, 16 Apr 2020 17:56:17 GMT", "version": "v1" } ]
2020-04-20
[ [ "Lu", "Jianlong", "" ] ]
In this paper, we consider a pair of entangled charged lepton-neutrino embedded in a constant magnetic field, which can be produced in the purely leptonic decay of charged pseudoscalar mesons. Particles with nonzero magnetic dipole moment will precess in the present of external magnetic field and induce a nontrivial noncyclic geometric phase. The dependence of this geometric phase on neutrino mass can be used to determine the Dirac/Majorana nature of massive neutrinos.
hep-ph/0112311
Kapogiannis Athanasios
A. S. Kapoyannis (University of Athens)
The path from chemical to thermal freeze-out
revised version
null
null
UA/NPPS-15-2001
hep-ph
null
The evolution of a hadronic system after its chemical decomposition is described through a model that conserves the hadronic multiplicities to their values at chemical freeze-out. The state of the system is found as function of temperature and the corresponding baryon density is evaluated. The baryon density at thermal decoupling is also computed.
[ { "created": "Fri, 21 Dec 2001 22:58:47 GMT", "version": "v1" }, { "created": "Fri, 8 Mar 2002 14:17:29 GMT", "version": "v2" } ]
2007-05-23
[ [ "Kapoyannis", "A. S.", "", "University of Athens" ] ]
The evolution of a hadronic system after its chemical decomposition is described through a model that conserves the hadronic multiplicities to their values at chemical freeze-out. The state of the system is found as function of temperature and the corresponding baryon density is evaluated. The baryon density at thermal decoupling is also computed.
hep-ph/9903543
null
Jonathan L. Rosner
On Large Final-State Phases in Heavy Meson Decays
24 pages, latex, 4 figures, to be submitted to Phys. Rev. D
Phys.Rev.D60:074029,1999
10.1103/PhysRevD.60.074029
EFI-99-10
hep-ph
null
An attempt is made to identify circumstances under which the weak decays of $D$ and $B$ mesons may display large differences between eigenphases of strong final-state interactions. There are several cases in which rescattering from other final states appears to enhance decay rates with respect to estimates based on the factorization hypothesis.
[ { "created": "Wed, 31 Mar 1999 16:47:22 GMT", "version": "v1" } ]
2014-11-17
[ [ "Rosner", "Jonathan L.", "" ] ]
An attempt is made to identify circumstances under which the weak decays of $D$ and $B$ mesons may display large differences between eigenphases of strong final-state interactions. There are several cases in which rescattering from other final states appears to enhance decay rates with respect to estimates based on the factorization hypothesis.
1804.08148
Ignazio Scimemi
Ignazio Scimemi, Alexey Vladimirov
Matching of transverse momentum dependent distributions at twist-3
Version accepted for pubblication
null
10.1140/epjc/s10052-018-6263-5
null
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive the leading order matching of the quark generated polarized transverse momentum dependent (TMD) distributions onto the collinear functions at small values of the transverse distance. Starting from the very definition of the TMD operator and performing the light-cone operator product expansion up to twist-3 order, we evaluate each distribution directly in position space. We primarily consider the cases of Sivers, Boer-Mulders and worm-gear functions. The effects of the TMD process dependence on the matching are explicitly shown. We also discuss the moments of TMD distributions which can be relevant for lattice calculations.
[ { "created": "Sun, 22 Apr 2018 18:15:40 GMT", "version": "v1" }, { "created": "Tue, 25 Sep 2018 07:39:30 GMT", "version": "v2" } ]
2018-10-17
[ [ "Scimemi", "Ignazio", "" ], [ "Vladimirov", "Alexey", "" ] ]
We derive the leading order matching of the quark generated polarized transverse momentum dependent (TMD) distributions onto the collinear functions at small values of the transverse distance. Starting from the very definition of the TMD operator and performing the light-cone operator product expansion up to twist-3 order, we evaluate each distribution directly in position space. We primarily consider the cases of Sivers, Boer-Mulders and worm-gear functions. The effects of the TMD process dependence on the matching are explicitly shown. We also discuss the moments of TMD distributions which can be relevant for lattice calculations.
hep-ph/0305120
H. J. Weber
W. R. B. de Ara\'ujo, T. Frederico, M. Beyer, H. J. Weber
Neutron Charge Radius: Relativistic Effects and the Foldy Term
12 pages, 5 figures, Latex, Int. J. Mod. Phys. A
Int.J.Mod.Phys. A18 (2003) 5767-5780
10.1142/S0217751X03015866
null
hep-ph
null
The neutron charge radius is studied within a light-front model with different spin coupling schemes and wave functions. The cancellation of the contributions from the Foldy term and Dirac form factor to the neutron charge form factor is verified for large nucleon sizes and it is independent of the detailed form of quark spin coupling and wave function. For the physical nucleon our results for the contribution of the Dirac form factor to the neutron radius are insensitive to the form of the wave function while they strongly depend on the quark spin coupling scheme.
[ { "created": "Mon, 12 May 2003 17:38:16 GMT", "version": "v1" } ]
2009-11-10
[ [ "de Araújo", "W. R. B.", "" ], [ "Frederico", "T.", "" ], [ "Beyer", "M.", "" ], [ "Weber", "H. J.", "" ] ]
The neutron charge radius is studied within a light-front model with different spin coupling schemes and wave functions. The cancellation of the contributions from the Foldy term and Dirac form factor to the neutron charge form factor is verified for large nucleon sizes and it is independent of the detailed form of quark spin coupling and wave function. For the physical nucleon our results for the contribution of the Dirac form factor to the neutron radius are insensitive to the form of the wave function while they strongly depend on the quark spin coupling scheme.
1001.5189
Jose W. F. Valle
J. W. F. Valle
Status of Neutrino Theory
12 pages, 11 composite figures (24 postscript files), plenary talk XXIV International Symposium on Lepton Photon Interactions at High Energies (Lepton Photon 09)
null
null
IFIC/10-04
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A summary of neutrino oscillation results is given along with a discussion of neutrino mass generation mechanisms, including high and low-scale seesaw, with and without supersymmetry, as well as recent attempts to understand flavor. I argue that if the origin of neutrino masses is intrinsically supersymmetric, it may lead to clear tests at the LHC. Finally, I briefly discuss thermal leptogenesis and dark matter.
[ { "created": "Thu, 28 Jan 2010 15:01:07 GMT", "version": "v1" }, { "created": "Sat, 30 Jan 2010 09:52:27 GMT", "version": "v2" } ]
2010-01-30
[ [ "Valle", "J. W. F.", "" ] ]
A summary of neutrino oscillation results is given along with a discussion of neutrino mass generation mechanisms, including high and low-scale seesaw, with and without supersymmetry, as well as recent attempts to understand flavor. I argue that if the origin of neutrino masses is intrinsically supersymmetric, it may lead to clear tests at the LHC. Finally, I briefly discuss thermal leptogenesis and dark matter.
hep-ph/0508146
Naveen Gaur
S. Rai Choudhury, Naveen Gaur and Ashok Goyal
Lepton number violation in Little Higgs model
revtex4.0 file, 5 pages including 8 eps figures, version to appear in Phys. Rev. D
Phys.Rev. D72 (2005) 097702
10.1103/PhysRevD.72.097702
null
hep-ph
null
In this note we examine the constraints imposed by muon anomalous magnetic moment ($(g-2)_\mu$) and $\mu^- \to e^+ e^- e^-$ on lepton number violating (LNV) couplings of the triplet Higgs in Little Higgs (LH) model.
[ { "created": "Fri, 12 Aug 2005 14:48:22 GMT", "version": "v1" }, { "created": "Mon, 7 Nov 2005 11:48:50 GMT", "version": "v2" } ]
2009-11-11
[ [ "Choudhury", "S. Rai", "" ], [ "Gaur", "Naveen", "" ], [ "Goyal", "Ashok", "" ] ]
In this note we examine the constraints imposed by muon anomalous magnetic moment ($(g-2)_\mu$) and $\mu^- \to e^+ e^- e^-$ on lepton number violating (LNV) couplings of the triplet Higgs in Little Higgs (LH) model.
1907.13207
Aidos Issadykov
Aidos Issadykov
$B_{s}\rightarrow K^{\ast 0}$ decay form factors from covariant confined quark model
null
EPJ Web Conf. 204 (2019) 08003
10.1051/epjconf/201920408003
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate $B_{s}\rightarrow K^{\ast 0}$ transition form factors in the full kinematical region within the covariant confined quark model. The calculated form factors can be used to calculate the $B_{s}\rightarrow K^{\ast 0}\mu^+ \mu^-$ rare decay branching ratio, which was recently measured by LHCb collaboration.
[ { "created": "Tue, 30 Jul 2019 20:05:18 GMT", "version": "v1" } ]
2019-08-01
[ [ "Issadykov", "Aidos", "" ] ]
We evaluate $B_{s}\rightarrow K^{\ast 0}$ transition form factors in the full kinematical region within the covariant confined quark model. The calculated form factors can be used to calculate the $B_{s}\rightarrow K^{\ast 0}\mu^+ \mu^-$ rare decay branching ratio, which was recently measured by LHCb collaboration.
1003.0740
Ken-iti Izawa
K.-I. Izawa, Y. Nakai, Ryo Takahashi
Nonlinearly Realized Extended Supergravity
19 pages
Phys.Rev.D82:075008,2010
10.1103/PhysRevD.82.075008
YITP-10-2
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We provide nonlinear realization of supergravity with an arbitrary number of supersymmetries by means of coset construction. The number of gravitino degrees of freedom counts the number of supersymmetries, which will be possibly probed in future experiments. We also consider goldstino embedding in the construction to discuss the relation to nonlinear realization with rigid supersymmetries.
[ { "created": "Wed, 3 Mar 2010 07:24:20 GMT", "version": "v1" } ]
2014-11-20
[ [ "Izawa", "K. -I.", "" ], [ "Nakai", "Y.", "" ], [ "Takahashi", "Ryo", "" ] ]
We provide nonlinear realization of supergravity with an arbitrary number of supersymmetries by means of coset construction. The number of gravitino degrees of freedom counts the number of supersymmetries, which will be possibly probed in future experiments. We also consider goldstino embedding in the construction to discuss the relation to nonlinear realization with rigid supersymmetries.
1309.0025
C.-P. Yuan
Sayipjamal Dulat, Tie-Jiun Hou, Jun Gao, Joey Huston, Jon Pumplin, Carl Schmidt, Daniel Stump, and C.-P. Yuan
Intrinsic Charm Parton Distribution Functions from CTEQ-TEA Global Analysis
35 pages, 20 figures and 2 tables
Phys. Rev. D 89, 073004 (2014)
10.1103/PhysRevD.89.073004
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the possibility of intrinsic (non-perturbative) charm in parton distribution functions (PDF) of the proton, within the context of the CT10 next-to-next-to-leading order (NNLO) global analysis. Three models for the intrinsic charm (IC) quark content are compared: (i) $\hat{c}(x) = 0$ (zero-IC model); (ii) $\hat{c}(x)$ is parametrized by a valence-like parton distribution (BHPS model); (iii) $\hat{c}(x)$ is parametrized by a sea-like parton distribution (SEA model). In these models, the intrinsic charm content, $\hat{c}(x)$, is included in the charm PDF at the matching scale $Q_c=m_c=1.3$ GeV. The best fits to data are constructed and compared. Correlations between the value of $m_c$ and the amount of IC are also considered.
[ { "created": "Fri, 30 Aug 2013 20:45:01 GMT", "version": "v1" }, { "created": "Tue, 19 Aug 2014 22:02:26 GMT", "version": "v2" } ]
2014-08-21
[ [ "Dulat", "Sayipjamal", "" ], [ "Hou", "Tie-Jiun", "" ], [ "Gao", "Jun", "" ], [ "Huston", "Joey", "" ], [ "Pumplin", "Jon", "" ], [ "Schmidt", "Carl", "" ], [ "Stump", "Daniel", "" ], [ "Yuan", "C. -P.", "" ] ]
We study the possibility of intrinsic (non-perturbative) charm in parton distribution functions (PDF) of the proton, within the context of the CT10 next-to-next-to-leading order (NNLO) global analysis. Three models for the intrinsic charm (IC) quark content are compared: (i) $\hat{c}(x) = 0$ (zero-IC model); (ii) $\hat{c}(x)$ is parametrized by a valence-like parton distribution (BHPS model); (iii) $\hat{c}(x)$ is parametrized by a sea-like parton distribution (SEA model). In these models, the intrinsic charm content, $\hat{c}(x)$, is included in the charm PDF at the matching scale $Q_c=m_c=1.3$ GeV. The best fits to data are constructed and compared. Correlations between the value of $m_c$ and the amount of IC are also considered.
1507.08643
Alan R. White
Alan R. White
The Gribov Legacy, Gauge Theories and the Physical S-Matrix
null
null
10.1142/S0217751X16450147
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Reggeon unitarity and non-abelian gauge field copies are focussed on as two Gribov discoveries that, it is suggested, may ultimately be seen as the most significant and that could, in the far distant future, form the cornerstones of his legacy. The crucial role played by the Gribov ambiguity in the construction of gauge theory bound-state amplitudes via reggeon unitarity is described. It is suggested that the existence of a physical, unitary, S-Matrix in a gauge theory is a major requirement that could even determine the theory.
[ { "created": "Wed, 29 Jul 2015 14:55:14 GMT", "version": "v1" } ]
2016-11-23
[ [ "White", "Alan R.", "" ] ]
Reggeon unitarity and non-abelian gauge field copies are focussed on as two Gribov discoveries that, it is suggested, may ultimately be seen as the most significant and that could, in the far distant future, form the cornerstones of his legacy. The crucial role played by the Gribov ambiguity in the construction of gauge theory bound-state amplitudes via reggeon unitarity is described. It is suggested that the existence of a physical, unitary, S-Matrix in a gauge theory is a major requirement that could even determine the theory.
1403.0037
Stefan H\"oche
Stefan Hoeche
Applications of higher order QCD
7 pages, 6 figures. Contribution to the proceedings of the international symposium on Physics in Collision 2013 (PIC 2013)
null
10.1142/S2010194514602816
SLAC-PUB-15867
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this talk we summarize some recent developments in perturbative QCD and their application to particle physics phenomenology.
[ { "created": "Sat, 1 Mar 2014 01:40:05 GMT", "version": "v1" } ]
2015-06-18
[ [ "Hoeche", "Stefan", "" ] ]
In this talk we summarize some recent developments in perturbative QCD and their application to particle physics phenomenology.
1209.6524
Christian Bogner
Christian Bogner and Francis Brown
Symbolic integration and multiple polylogarithms
8 pages, proceedings of the 11th DESY workshop "Loops and Legs in Quantum Field Theory", April 2012, Wernigerode, Germany
null
null
null
hep-ph math-ph math.MP
http://creativecommons.org/licenses/by-nc-sa/3.0/
We review a method for the algebraic treatment of a family of functions which contains the multiple polylogarithms, with applications to the symbolic calculation of Feynman integrals.
[ { "created": "Fri, 28 Sep 2012 14:09:04 GMT", "version": "v1" } ]
2012-10-01
[ [ "Bogner", "Christian", "" ], [ "Brown", "Francis", "" ] ]
We review a method for the algebraic treatment of a family of functions which contains the multiple polylogarithms, with applications to the symbolic calculation of Feynman integrals.
1806.07340
Kirill Tuchin
Kirill Tuchin
Radiative instability of quantum electrodynamics in chiral matter
13 pages. v2: error in IVA corrected, explanations and references added, typos fixed
null
10.1016/j.physletb.2018.09.055
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Modification of the photon dispersion relation in chiral matter enables $1\to 2$ scattering. As a result, the single fermion and photon states are unstable to photon radiation and pair production respectively. In particular, a fast fermion moving through chiral matter can spontaneously radiate a photon, while a photon can spontaneously radiate a fast fermion and anti-fermion pair. The corresponding spectra are derived in the ultra-relativistic approximation. It is shown that the polarization of the produced and decayed photons is determined by the sign of the chiral conductivity. Impact of a flat thin domain wall on the spectra is computed.
[ { "created": "Tue, 19 Jun 2018 16:49:35 GMT", "version": "v1" }, { "created": "Wed, 29 Aug 2018 16:17:31 GMT", "version": "v2" } ]
2018-11-14
[ [ "Tuchin", "Kirill", "" ] ]
Modification of the photon dispersion relation in chiral matter enables $1\to 2$ scattering. As a result, the single fermion and photon states are unstable to photon radiation and pair production respectively. In particular, a fast fermion moving through chiral matter can spontaneously radiate a photon, while a photon can spontaneously radiate a fast fermion and anti-fermion pair. The corresponding spectra are derived in the ultra-relativistic approximation. It is shown that the polarization of the produced and decayed photons is determined by the sign of the chiral conductivity. Impact of a flat thin domain wall on the spectra is computed.
hep-ph/0009354
Fulvio Piccinini
G. Montagna, M. Moretti, M. Osmo, A. Pallavicini, F. Piccinini
Non Abelian Gauge Couplings in Four Fermion Processes at LEP
LaTeX, 5 pages. Talk given by F. Piccinini at IV Rencontres du Vietnam: International Conference on Physics at Extreme Energies (Particle Physics and Astrophysics), Hanoi, Vietnam, 19-25 July 2000
null
null
FNT/T-2000/16
hep-ph
null
The LEP data on four fermion processes are presently used to study the non abelian gauge couplings of the Standard Model. The present theoretical error for two classes of processes, single-W production and radiative four fermion final states, is discussed according to the results of the four fermion working group of the LEP2 Monte Carlo Workshop held at CERN.
[ { "created": "Fri, 29 Sep 2000 15:34:49 GMT", "version": "v1" } ]
2007-05-23
[ [ "Montagna", "G.", "" ], [ "Moretti", "M.", "" ], [ "Osmo", "M.", "" ], [ "Pallavicini", "A.", "" ], [ "Piccinini", "F.", "" ] ]
The LEP data on four fermion processes are presently used to study the non abelian gauge couplings of the Standard Model. The present theoretical error for two classes of processes, single-W production and radiative four fermion final states, is discussed according to the results of the four fermion working group of the LEP2 Monte Carlo Workshop held at CERN.
1702.02493
Chandan Mondal
Tanmay Maji, Chandan Mondal, Dipankar Chakrabarti
Leading twist generalized parton distributions and spin densities in a proton
27 pages, 12 figures; version published in PRD
Phys. Rev. D 96, 013006 (2017)
10.1103/PhysRevD.96.013006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We evaluate both chirally even and odd generalized parton distributions(GPDs) in the leading twist in a recently proposed quark-diquark model for the proton where the light front wavefunctions are constructed from the soft-wall AdS/QCD prediction. The GPDs in transverse impact parameter space give the spin densities for different quark and proton polarizations. For longitudinally polarized proton only chiral even GPDs contribute but for transversely polarized proton both chiral even and chiral odd GPDs contribute to the spin densities. We present a detail study of the spin densities in this model.
[ { "created": "Wed, 8 Feb 2017 16:25:03 GMT", "version": "v1" }, { "created": "Fri, 28 Jul 2017 15:38:34 GMT", "version": "v2" } ]
2017-08-02
[ [ "Maji", "Tanmay", "" ], [ "Mondal", "Chandan", "" ], [ "Chakrabarti", "Dipankar", "" ] ]
We evaluate both chirally even and odd generalized parton distributions(GPDs) in the leading twist in a recently proposed quark-diquark model for the proton where the light front wavefunctions are constructed from the soft-wall AdS/QCD prediction. The GPDs in transverse impact parameter space give the spin densities for different quark and proton polarizations. For longitudinally polarized proton only chiral even GPDs contribute but for transversely polarized proton both chiral even and chiral odd GPDs contribute to the spin densities. We present a detail study of the spin densities in this model.
1512.01902
S. H. Kahana
D. E. Kahana and S. H. Kahana
LHCb $P_c^+$ Resonances as Molecular States
7 pages, 2 figures, LaTeX: corrected typos and references
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recent experiments at the LHCb detector have once again raised the possibility that quark bags may exist containing more than three quarks. Specifically the LHCb collaboration points to evidence for hadronic resonances decaying into J/$\psi$ and proton: the $P_c(4450)^+$ and $P_C(4380)^+$. Here we put forth a case that a reasonable description of these states is possible as molecular resonances of a $p$ and a J/$\psi$. Our model seems to accommodate the observed states and their measured widths, both the lower lying, broader, negative parity state and the higher lying, narrow positive parity state. If these resonances do indeed exist one might envision a rich spectroscopy of such pentaquark states waiting to be discovered, though this would deepen the mystery of their absence in earlier hadron spectroscopy. Perhaps the presence of the heavy charmed quarks, as well as the lighter u,d and s quarks, is the determining factor.
[ { "created": "Mon, 7 Dec 2015 03:40:35 GMT", "version": "v1" }, { "created": "Thu, 10 Dec 2015 09:47:39 GMT", "version": "v2" } ]
2015-12-11
[ [ "Kahana", "D. E.", "" ], [ "Kahana", "S. H.", "" ] ]
Recent experiments at the LHCb detector have once again raised the possibility that quark bags may exist containing more than three quarks. Specifically the LHCb collaboration points to evidence for hadronic resonances decaying into J/$\psi$ and proton: the $P_c(4450)^+$ and $P_C(4380)^+$. Here we put forth a case that a reasonable description of these states is possible as molecular resonances of a $p$ and a J/$\psi$. Our model seems to accommodate the observed states and their measured widths, both the lower lying, broader, negative parity state and the higher lying, narrow positive parity state. If these resonances do indeed exist one might envision a rich spectroscopy of such pentaquark states waiting to be discovered, though this would deepen the mystery of their absence in earlier hadron spectroscopy. Perhaps the presence of the heavy charmed quarks, as well as the lighter u,d and s quarks, is the determining factor.
hep-ph/9401297
Stefano Moretti
Stefano Moretti
Intermediate mass Higgs bosons at TeV $e\gamma$ colliders in the ${\cal {MSSM}}$
24 pages and 9 figures (figs.1-4 included, figs.5-9 will be sent on request), LaTex file (uses Feynman.tex), Turin Univ. preprint DFTT 79/93 (Some control sequences undefined in previous version have been added)
Phys.Rev.D50:2016-2030,1994
10.1103/PhysRevD.50.2016
null
hep-ph
null
We study the cross sections for the production of intermediate mass Higgs bosons via the reactions $e^-\gamma\rightarrow \nu_eW^-\Phi^0$, $e^-\gamma\rightarrow \nu_eH^-\Phi^0$, $e^-\gamma\rightarrow e^-Z^0\Phi^0$ and $e^-\gamma\rightarrow e^-H^+H^-$ in the Minimal Supersymmetric Standard Model (with $\Phi^0=H^0,h^0$ and, where possible, $A^0$) at TeV energies, taking into account $b$--tagging capabilities. We find that the rates for $e^-\gamma\rightarrow \nu_eW^-\Phi^0$ are large enough to permit the discovery of at least one between $h^0$ and $H^0$ over the whole intermediate mass range of $M_{A^0}$, at all $\tan\beta$, using the $(jj)(b\bar b)$ final state. The ${\cal {CP}}$-odd neutral $A^0$ and the charged $H^\pm$'s can be detected via the processes $e^-\gamma\rightarrow \nu_eH^-A^0$, with $A^0\rightarrow b\bar b$, and $e^-\gamma\rightarrow e^-H^+H^-$, resorting to the leptonic decay $H^\pm\rightarrow \nu_\tau\tau^+(\bar\nu_\tau\tau^-)$, but only for $M_{A^0}\approx60$ GeV. Finally, we present explicit formulae for the helicity amplitudes of these processes.
[ { "created": "Thu, 20 Jan 1994 20:27:12 GMT", "version": "v1" }, { "created": "Mon, 24 Jan 1994 18:24:13 GMT", "version": "v2" } ]
2014-11-17
[ [ "Moretti", "Stefano", "" ] ]
We study the cross sections for the production of intermediate mass Higgs bosons via the reactions $e^-\gamma\rightarrow \nu_eW^-\Phi^0$, $e^-\gamma\rightarrow \nu_eH^-\Phi^0$, $e^-\gamma\rightarrow e^-Z^0\Phi^0$ and $e^-\gamma\rightarrow e^-H^+H^-$ in the Minimal Supersymmetric Standard Model (with $\Phi^0=H^0,h^0$ and, where possible, $A^0$) at TeV energies, taking into account $b$--tagging capabilities. We find that the rates for $e^-\gamma\rightarrow \nu_eW^-\Phi^0$ are large enough to permit the discovery of at least one between $h^0$ and $H^0$ over the whole intermediate mass range of $M_{A^0}$, at all $\tan\beta$, using the $(jj)(b\bar b)$ final state. The ${\cal {CP}}$-odd neutral $A^0$ and the charged $H^\pm$'s can be detected via the processes $e^-\gamma\rightarrow \nu_eH^-A^0$, with $A^0\rightarrow b\bar b$, and $e^-\gamma\rightarrow e^-H^+H^-$, resorting to the leptonic decay $H^\pm\rightarrow \nu_\tau\tau^+(\bar\nu_\tau\tau^-)$, but only for $M_{A^0}\approx60$ GeV. Finally, we present explicit formulae for the helicity amplitudes of these processes.
1808.08957
Tobias Isken
Maximilian Dax, Tobias Isken, Bastian Kubis
Quark-mass dependence in $\omega\to3\pi$ decays
12 pages, 8 figures; v2: added two references, version published in EPJC
Eur. Phys. J. C78 (2018) 859
10.1140/epjc/s10052-018-6346-3
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the quark-mass dependence of $\omega\to3\pi$ decays, based on a dispersion-theoretical framework. We rely on the quark-mass-dependent scattering phase shift for the pion-pion $P$-wave extracted from unitarized chiral perturbation theory. The dispersive representation then takes into account the final-state rescattering among all three pions. The described formalism may be used as an extrapolation tool for lattice QCD calculations of three-pion decays, for which $\omega\to3\pi$ can serve as a paradigm case.
[ { "created": "Mon, 27 Aug 2018 18:00:01 GMT", "version": "v1" }, { "created": "Tue, 30 Oct 2018 13:57:59 GMT", "version": "v2" } ]
2018-10-31
[ [ "Dax", "Maximilian", "" ], [ "Isken", "Tobias", "" ], [ "Kubis", "Bastian", "" ] ]
We study the quark-mass dependence of $\omega\to3\pi$ decays, based on a dispersion-theoretical framework. We rely on the quark-mass-dependent scattering phase shift for the pion-pion $P$-wave extracted from unitarized chiral perturbation theory. The dispersive representation then takes into account the final-state rescattering among all three pions. The described formalism may be used as an extrapolation tool for lattice QCD calculations of three-pion decays, for which $\omega\to3\pi$ can serve as a paradigm case.
2401.02522
John Verges
Jos\'e F. Nieves, John D. Verges
Kinetic theory formulation of the $P$- and $CP$-odd terms in the photon self-energy in a medium
Typographical errors have been corrected; identical to the published version Phys. Rev. D 109, 056022
null
10.1103/PhysRevD.109.056022
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In an optically active medium, such as a plasma that contains a neutrino background, the left-handed and right-handed polarization photon modes acquire different dispersion relations. We study the propagation of photons in such a medium, which is otherwise isotropic, within the framework of the covariant collissionless Boltzmann equation incorporating a term that parametrizes the optical activity. Using the linear response approximation, we obtain the formulas for the components of the photon polarization tensor, expressed in terms of integrals over the momentum distribution function of the background particles. The main result here is the formula for the P- and CP-breaking component of the photon polarization tensor in terms of the parameter involved in the new term we consider in the Boltzmann equation to describe the effects of optical activity. We discuss the results for some particular cases, such as long-wavelength and non-relativistic limits, for illustrate purposes. We also discuss the generalizations of the P- and CP-breaking term we included in the Boltzmann equation. In particular we consider the application to a plasma with a neutrino background and establish contact with calculations of the photon self-energy in those systems in the framework of Thermal Field Theory.
[ { "created": "Thu, 4 Jan 2024 20:17:22 GMT", "version": "v1" }, { "created": "Tue, 26 Mar 2024 22:35:33 GMT", "version": "v2" } ]
2024-03-28
[ [ "Nieves", "José F.", "" ], [ "Verges", "John D.", "" ] ]
In an optically active medium, such as a plasma that contains a neutrino background, the left-handed and right-handed polarization photon modes acquire different dispersion relations. We study the propagation of photons in such a medium, which is otherwise isotropic, within the framework of the covariant collissionless Boltzmann equation incorporating a term that parametrizes the optical activity. Using the linear response approximation, we obtain the formulas for the components of the photon polarization tensor, expressed in terms of integrals over the momentum distribution function of the background particles. The main result here is the formula for the P- and CP-breaking component of the photon polarization tensor in terms of the parameter involved in the new term we consider in the Boltzmann equation to describe the effects of optical activity. We discuss the results for some particular cases, such as long-wavelength and non-relativistic limits, for illustrate purposes. We also discuss the generalizations of the P- and CP-breaking term we included in the Boltzmann equation. In particular we consider the application to a plasma with a neutrino background and establish contact with calculations of the photon self-energy in those systems in the framework of Thermal Field Theory.
2203.00693
Joel Barir
Joel Barir, Michael Geller, Chen Sun, Tomer Volansky
Gravitational Waves from Incomplete Inflationary Phase Transitions
12 pages, 4 figures
null
10.1103/PhysRevD.108.115016
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the observable implications of an incomplete first order phase transition during inflation. In such a phase transition, the nucleated bubbles do not percolate and instead are continuously produced until the onset of reheating. The process creates an inhomogeneity with a distinct power spectrum that depends on both the physics of the phase transition and the inflationary dynamics. Upon horizon re-entry, this spectrum generates gravitational waves through non-linear effects. This stochastic gravitational wave background is predicted to have unique signatures that may be detectable by future experiments spanning a wide frequency range. The discovery of such a gravitational wave signal would shed a light on the detailed dynamics of inflation.
[ { "created": "Tue, 1 Mar 2022 19:00:00 GMT", "version": "v1" } ]
2023-12-20
[ [ "Barir", "Joel", "" ], [ "Geller", "Michael", "" ], [ "Sun", "Chen", "" ], [ "Volansky", "Tomer", "" ] ]
We study the observable implications of an incomplete first order phase transition during inflation. In such a phase transition, the nucleated bubbles do not percolate and instead are continuously produced until the onset of reheating. The process creates an inhomogeneity with a distinct power spectrum that depends on both the physics of the phase transition and the inflationary dynamics. Upon horizon re-entry, this spectrum generates gravitational waves through non-linear effects. This stochastic gravitational wave background is predicted to have unique signatures that may be detectable by future experiments spanning a wide frequency range. The discovery of such a gravitational wave signal would shed a light on the detailed dynamics of inflation.
1104.2118
Xu-Hao Yuan
Xu-Hao Yuan, Liang Tang, Mao-Zhi Yang and Xue-Qian Li
Study on the mixing among the $0^{++}$ mesons around $1\sim 2$ $\mathrm{GeV}$ with the QCD sum rules
15 pages, 6 figures, discussion slightly modified and more references added
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the correlation functions of $0^{++}$ $q\bar q$, $s\bar s$ and glueball in the QCD sum rules and obtain the mass matrix where non-diagonal terms are determined by the cross correlations among the three states. Diagonalizing the mass matrix and identifying the eigenstates as the physical $0^{++}$ scalar mesons, we can determine the mixing. Concretely, our calculations determine the fractions of $q\bar q$, $s\bar s$ and glueball in the physical states $f_0(1370)$, $f_0(1500)$ and $f_0(1710)$, the results are consistent with that gained by the phenomenological research.
[ { "created": "Tue, 12 Apr 2011 06:13:42 GMT", "version": "v1" }, { "created": "Mon, 18 Apr 2011 17:38:18 GMT", "version": "v2" } ]
2015-03-19
[ [ "Yuan", "Xu-Hao", "" ], [ "Tang", "Liang", "" ], [ "Yang", "Mao-Zhi", "" ], [ "Li", "Xue-Qian", "" ] ]
We calculate the correlation functions of $0^{++}$ $q\bar q$, $s\bar s$ and glueball in the QCD sum rules and obtain the mass matrix where non-diagonal terms are determined by the cross correlations among the three states. Diagonalizing the mass matrix and identifying the eigenstates as the physical $0^{++}$ scalar mesons, we can determine the mixing. Concretely, our calculations determine the fractions of $q\bar q$, $s\bar s$ and glueball in the physical states $f_0(1370)$, $f_0(1500)$ and $f_0(1710)$, the results are consistent with that gained by the phenomenological research.
hep-ph/9805505
Valery Khoze
Valery A. Khoze
Interconnection phenomena in $W^+W^-$ and $t\bar t$ events
15 pages, Latex
null
null
CERN-TH/98-176
hep-ph
null
I will attempt to survey some selected physics issues on QCD interconnection phenomena in the processes $e^+e^-\to W^+W^-\to$ 4 jets and $e^+e^-\to t\bar t \to b W^+\bar b W^-$. Possible consequences for LEP2 and future linear $e^+e^-$ colliders are briefly discussed.
[ { "created": "Fri, 29 May 1998 14:05:23 GMT", "version": "v1" } ]
2007-05-23
[ [ "Khoze", "Valery A.", "" ] ]
I will attempt to survey some selected physics issues on QCD interconnection phenomena in the processes $e^+e^-\to W^+W^-\to$ 4 jets and $e^+e^-\to t\bar t \to b W^+\bar b W^-$. Possible consequences for LEP2 and future linear $e^+e^-$ colliders are briefly discussed.
1304.7249
Peter Millington
Peter Millington and Apostolos Pilaftsis
Perturbative Non-Equilibrium Thermal Field Theory to all Orders in Gradient Expansion
7 pages, 4 figures; version accepted for publication in Physics Letters B
Phys.Lett.B724:56-62,2013
10.1016/j.physletb.2013.05.044
MAN/HEP/2013/06
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a new perturbative formulation of non-equilibrium thermal field theory, based upon non-homogeneous free propagators and time-dependent vertices. The resulting time-dependent diagrammatic perturbation series are free of pinch singularities without the need for quasi-particle approximation or effective resummation of finite widths. After arriving at a physically meaningful definition of particle number densities, we derive master time evolution equations for statistical distribution functions, which are valid to all orders in perturbation theory and to all orders in a gradient expansion. For a scalar model, we perform a perturbative loopwise truncation of these evolution equations, whilst still capturing fast transient behaviour, which is found to be dominated by energy-violating processes, leading to the non-Markovian evolution of memory effects.
[ { "created": "Fri, 26 Apr 2013 18:20:36 GMT", "version": "v1" }, { "created": "Thu, 6 Jun 2013 13:00:18 GMT", "version": "v2" } ]
2013-07-31
[ [ "Millington", "Peter", "" ], [ "Pilaftsis", "Apostolos", "" ] ]
We present a new perturbative formulation of non-equilibrium thermal field theory, based upon non-homogeneous free propagators and time-dependent vertices. The resulting time-dependent diagrammatic perturbation series are free of pinch singularities without the need for quasi-particle approximation or effective resummation of finite widths. After arriving at a physically meaningful definition of particle number densities, we derive master time evolution equations for statistical distribution functions, which are valid to all orders in perturbation theory and to all orders in a gradient expansion. For a scalar model, we perform a perturbative loopwise truncation of these evolution equations, whilst still capturing fast transient behaviour, which is found to be dominated by energy-violating processes, leading to the non-Markovian evolution of memory effects.
2211.04694
Piotr Bargiela
Piotr Bargiela
Three-loop four-particle QCD amplitudes
6 pages, 1 figure, ICHEP 2022
null
null
null
hep-ph hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present recent advancements in the computation of three-loop four-particle helicity amplitudes in full-color massless QCD. In this contribution, we focus on the $gg \to \gamma\gamma$ process. We show how to obtain compact analytic formulae for the three-loop scattering amplitude. Our results can be expressed in terms of harmonic polylogarithms, which allows for an efficient numerical evaluation. The results presented here can be used for improving theoretical predictions relevant for Higgs physics at hadron colliders.
[ { "created": "Wed, 9 Nov 2022 06:00:08 GMT", "version": "v1" } ]
2022-11-10
[ [ "Bargiela", "Piotr", "" ] ]
We present recent advancements in the computation of three-loop four-particle helicity amplitudes in full-color massless QCD. In this contribution, we focus on the $gg \to \gamma\gamma$ process. We show how to obtain compact analytic formulae for the three-loop scattering amplitude. Our results can be expressed in terms of harmonic polylogarithms, which allows for an efficient numerical evaluation. The results presented here can be used for improving theoretical predictions relevant for Higgs physics at hadron colliders.
hep-ph/9812476
Daniel Cormier
D. Cormier and R. Holman
Spinodal Inflation
4 pages, 1 epsf figure
Phys.Rev.D60:041301,1999
10.1103/PhysRevD.60.041301
null
hep-ph astro-ph
null
Out-of-equilibrium, non-perturbative, quantum effects significantly modify the standard picture of inflation in a wide class of models including new, natural, and hybrid inflation. We find that the quantum evolution of a single real inflaton field may be modeled by a classical theory of two homogeneous scalar fields. We briefly discuss the important observational consequences that are expected to result.
[ { "created": "Tue, 22 Dec 1998 16:29:48 GMT", "version": "v1" } ]
2010-01-06
[ [ "Cormier", "D.", "" ], [ "Holman", "R.", "" ] ]
Out-of-equilibrium, non-perturbative, quantum effects significantly modify the standard picture of inflation in a wide class of models including new, natural, and hybrid inflation. We find that the quantum evolution of a single real inflaton field may be modeled by a classical theory of two homogeneous scalar fields. We briefly discuss the important observational consequences that are expected to result.
hep-ph/0404038
Lotfi Boubekeur
L. Boubekeur (Lancaster), T. Hambye (Oxford) and G. Senjanovic (ICTP)
Low-scale leptogenesis and soft supersymmetry breaking
4 pages, revtex, uses axodraw. Minor changes to match acccepted version in PRL
Phys.Rev.Lett. 93 (2004) 111601
10.1103/PhysRevLett.93.111601
null
hep-ph
null
We investigate the possibility of low-scale leptogenesis in the minimal supersymmetric standard model extended with right handed (s)neutrinos. We demonstrate that successful leptogenesis can be easily achieved at a scale as low as ~ TeV where lepton number and CP violation comes from soft supersymmetry breaking terms. The scenario is shown to be compatible with neutrino masses data.
[ { "created": "Mon, 5 Apr 2004 13:33:41 GMT", "version": "v1" }, { "created": "Tue, 7 Sep 2004 10:48:42 GMT", "version": "v2" } ]
2009-11-10
[ [ "Boubekeur", "L.", "", "Lancaster" ], [ "Hambye", "T.", "", "Oxford" ], [ "Senjanovic", "G.", "", "ICTP" ] ]
We investigate the possibility of low-scale leptogenesis in the minimal supersymmetric standard model extended with right handed (s)neutrinos. We demonstrate that successful leptogenesis can be easily achieved at a scale as low as ~ TeV where lepton number and CP violation comes from soft supersymmetry breaking terms. The scenario is shown to be compatible with neutrino masses data.
0909.4530
Roman Nevzorov
P. Athron (1), S. F. King (2), R. Luo (3), D. J. Miller (3), S. Moretti (2 and 4), R. Nevzorov (3) ((1) TU Dresden, (2) University of Southampton, (3) University of Glasgow, (4) Turin University)
Unification of Gauge Couplings in the E(6)SSM
Parallel talk at SUSY09, Boston, USA, June 2009, 5 pages
AIP Conf.Proc.1200:466-469,2010
10.1063/1.3327630
SHEP-09-21, DFTT 61/2009
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We argue that in the two-loop approximation gauge coupling unification in the exceptional supersymmetric standard model can be achieved for any phenomenologically reasonable value of strong gauge coupling at the electroweak scale consistent with the experimentally measured central value.
[ { "created": "Thu, 24 Sep 2009 19:55:53 GMT", "version": "v1" }, { "created": "Thu, 24 Sep 2009 20:32:42 GMT", "version": "v2" } ]
2015-05-14
[ [ "Athron", "P.", "", "2 and 4" ], [ "King", "S. F.", "", "2 and 4" ], [ "Luo", "R.", "", "2 and 4" ], [ "Miller", "D. J.", "", "2 and 4" ], [ "Moretti", "S.", "", "2 and 4" ], [ "Nevzorov", "R.", "" ] ]
We argue that in the two-loop approximation gauge coupling unification in the exceptional supersymmetric standard model can be achieved for any phenomenologically reasonable value of strong gauge coupling at the electroweak scale consistent with the experimentally measured central value.
1202.4266
Javier Virto
Joaquim Matias, Federico Mescia, Marc Ramon, Javier Virto
Complete Anatomy of B -> K*ll and its angular distribution
37 pages, 12 Figures. Corrected typo in Eqs. (29) and (44). Results and conclusions unchanged
JHEP, 1204:104, 2012
10.1007/JHEP04(2012)104
UAB-FT-706; ICCUB-12-076; ECM-UB 68
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a complete and optimal set of observables for the exclusive 4-body B meson decay B -> K*(->K pi) l+l- in the low dilepton mass region, that contains a maximal number of clean observables. This basis of observables is built in a systematic way. We show that all the previously defined observables and any observable that one can construct, can be expressed as a function of this basis. This set of observables contains all the information that can be extracted from the angular distribution in the cleanest possible way. We provide explicit expressions for the full and the uniangular distributions in terms of this basis. The conclusions presented here can be easily extended to the large-q^2 region. We study the sensitivity of the observables to right-handed currents and scalars. Finally, we present for the first time all the symmetries of the full distribution including massive terms and scalar contributions.
[ { "created": "Mon, 20 Feb 2012 09:35:17 GMT", "version": "v1" }, { "created": "Wed, 2 May 2012 14:21:33 GMT", "version": "v2" }, { "created": "Tue, 17 Jul 2012 10:53:12 GMT", "version": "v3" } ]
2015-06-04
[ [ "Matias", "Joaquim", "" ], [ "Mescia", "Federico", "" ], [ "Ramon", "Marc", "" ], [ "Virto", "Javier", "" ] ]
We present a complete and optimal set of observables for the exclusive 4-body B meson decay B -> K*(->K pi) l+l- in the low dilepton mass region, that contains a maximal number of clean observables. This basis of observables is built in a systematic way. We show that all the previously defined observables and any observable that one can construct, can be expressed as a function of this basis. This set of observables contains all the information that can be extracted from the angular distribution in the cleanest possible way. We provide explicit expressions for the full and the uniangular distributions in terms of this basis. The conclusions presented here can be easily extended to the large-q^2 region. We study the sensitivity of the observables to right-handed currents and scalars. Finally, we present for the first time all the symmetries of the full distribution including massive terms and scalar contributions.
hep-ph/0007342
Louis J. Clavelli
L. Clavelli, T. Gajdosik, W. Majerotto
Gaugino Mass Dependence of Electron and Neutron Electric Dipole Moments
13 pages, 3 figures
Phys.Lett. B494 (2000) 287-296
10.1016/S0370-2693(00)01201-6
null
hep-ph
null
Unless squarks and sleptons are in the multi-TeV region or above, CP violating induced electric dipole moments of elementary particles can pose significant puzzles for supersymmetric (SUSY) models. We study the dipole-moment-inducing one-loop amplitudes as a function of the fundamental SUSY parameters and show that these puzzles are removed if there is a sufficiently large hierarchy between the gaugino masses and the scalar mass. We comment on the experimental status of the low gaugino mass scenario.
[ { "created": "Fri, 28 Jul 2000 21:36:20 GMT", "version": "v1" } ]
2009-10-31
[ [ "Clavelli", "L.", "" ], [ "Gajdosik", "T.", "" ], [ "Majerotto", "W.", "" ] ]
Unless squarks and sleptons are in the multi-TeV region or above, CP violating induced electric dipole moments of elementary particles can pose significant puzzles for supersymmetric (SUSY) models. We study the dipole-moment-inducing one-loop amplitudes as a function of the fundamental SUSY parameters and show that these puzzles are removed if there is a sufficiently large hierarchy between the gaugino masses and the scalar mass. We comment on the experimental status of the low gaugino mass scenario.
0705.2007
Carlos Munoz
C. Munoz
SUSY: New Perspectives and Variants
Small modifications in text and references. Review prepared for Moriond 2006. 12 pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Although supersymmetry (SUSY) is thirty five years old, it is still one of the most attractive theories for physics beyond the standard model. Assuming that SUSY will be discovered at the LHC, the key question is: What SUSY model do we expect to be the correct one ? After reviewing briefly the advantages and problems of SUSY, several interesting models that have been proposed in the literature will be discussed. In particular, models such as the MSSM, BRpV, NMSSM, and possible extensions. We will also introduce the $\mu\nuSSM$ whose interest resides in the fact that it generates a solution to the (famous) $\mu$ problem of SUSY models that is connected to the (nowadays very popular) neutrino physics.
[ { "created": "Mon, 14 May 2007 19:35:40 GMT", "version": "v1" }, { "created": "Thu, 10 Jan 2013 19:00:21 GMT", "version": "v2" } ]
2013-01-11
[ [ "Munoz", "C.", "" ] ]
Although supersymmetry (SUSY) is thirty five years old, it is still one of the most attractive theories for physics beyond the standard model. Assuming that SUSY will be discovered at the LHC, the key question is: What SUSY model do we expect to be the correct one ? After reviewing briefly the advantages and problems of SUSY, several interesting models that have been proposed in the literature will be discussed. In particular, models such as the MSSM, BRpV, NMSSM, and possible extensions. We will also introduce the $\mu\nuSSM$ whose interest resides in the fact that it generates a solution to the (famous) $\mu$ problem of SUSY models that is connected to the (nowadays very popular) neutrino physics.
1212.0644
Sergey Mikhailov
A. P. Bakulev, S. V. Mikhailov, A. V. Pimikov, N. G. Stefanis
Emphasizing the different trends of the existing data for the $\gamma^*\gamma \to \pi^0$ transition form factor
8 pages, 6 figures, Presented at Light-Cone 2012, July 08-13, 2012, Cracow, Poland
null
null
RUB-TPII-05/2012; FTUV-12-11-30
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The new data on the $\gamma^*\gamma \to \pi^0$ transition form factor of the Belle Collaboration are analyzed in comparison with those of BaBar (including the older data of CELLO and CLEO) using an approach based on light-cone sum rules. Performing a 2-, and a 3-parametric fit to these data, we found that the Belle and the BaBar data have no overlap at the $1\sigma$ level. While the Belle data agree with our predictions, the Babar data are in conflict with them.
[ { "created": "Tue, 4 Dec 2012 09:02:03 GMT", "version": "v1" }, { "created": "Wed, 5 Dec 2012 13:37:22 GMT", "version": "v2" } ]
2012-12-06
[ [ "Bakulev", "A. P.", "" ], [ "Mikhailov", "S. V.", "" ], [ "Pimikov", "A. V.", "" ], [ "Stefanis", "N. G.", "" ] ]
The new data on the $\gamma^*\gamma \to \pi^0$ transition form factor of the Belle Collaboration are analyzed in comparison with those of BaBar (including the older data of CELLO and CLEO) using an approach based on light-cone sum rules. Performing a 2-, and a 3-parametric fit to these data, we found that the Belle and the BaBar data have no overlap at the $1\sigma$ level. While the Belle data agree with our predictions, the Babar data are in conflict with them.
1803.00950
Jonas Michael Lindert
Christian G\"utschow, Jonas M. Lindert, Marek Sch\"onherr
Multi-jet merged top-pair production including electroweak corrections
10 pages, 5 figures
null
10.1140/epjc/s10052-018-5804-2
CERN-TH-18-039, IPPP/18/13, MCnet-18-05
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present theoretical predictions for the production of top-quark pairs in association with jets at the LHC including electroweak (EW) corrections. First, we present and compare differential predictions at the fixed-order level for $t \bar t$ and $t \bar t+$jet production at the LHC considering the dominant NLO EW corrections of order $\mathcal{O}(\alpha_S^2 \alpha)$ and $\mathcal{O}(\alpha_S^3 \alpha)$ respectively together with all additional subleading Born and one-loop contributions. The NLO EW corrections are enhanced at large energies and in particular alter the shape of the top transverse momentum distribution, whose reliable modelling is crucial for many searches for new physics at the energy frontier. Based on the fixed-order results we motivate an approximation of the EW corrections valid at the percent level, that allows us to readily incorporate the EW corrections in the MEPS@NLO framework of Sherpa combined with OpenLoops. Subsequently, we present multi-jet merged parton-level predictions for inclusive top-pair production incorporating NLO QCD+EW corrections to $t \bar t$ and $t \bar t+$jet. Finally, we compare at the particle-level against a recent 8 TeV measurement of the top transverse momentum distribution performed by ATLAS in the lepton+jet channel. We find very good agreement between the Monte Carlo prediction and the data when the EW corrections are included.
[ { "created": "Fri, 2 Mar 2018 17:05:59 GMT", "version": "v1" } ]
2018-05-09
[ [ "Gütschow", "Christian", "" ], [ "Lindert", "Jonas M.", "" ], [ "Schönherr", "Marek", "" ] ]
We present theoretical predictions for the production of top-quark pairs in association with jets at the LHC including electroweak (EW) corrections. First, we present and compare differential predictions at the fixed-order level for $t \bar t$ and $t \bar t+$jet production at the LHC considering the dominant NLO EW corrections of order $\mathcal{O}(\alpha_S^2 \alpha)$ and $\mathcal{O}(\alpha_S^3 \alpha)$ respectively together with all additional subleading Born and one-loop contributions. The NLO EW corrections are enhanced at large energies and in particular alter the shape of the top transverse momentum distribution, whose reliable modelling is crucial for many searches for new physics at the energy frontier. Based on the fixed-order results we motivate an approximation of the EW corrections valid at the percent level, that allows us to readily incorporate the EW corrections in the MEPS@NLO framework of Sherpa combined with OpenLoops. Subsequently, we present multi-jet merged parton-level predictions for inclusive top-pair production incorporating NLO QCD+EW corrections to $t \bar t$ and $t \bar t+$jet. Finally, we compare at the particle-level against a recent 8 TeV measurement of the top transverse momentum distribution performed by ATLAS in the lepton+jet channel. We find very good agreement between the Monte Carlo prediction and the data when the EW corrections are included.
2101.06200
Daniel Pitonyak
Leonard Gamberg, Zhong-Bo Kang, Daniel Pitonyak, Alexei Prokudin, Nobuo Sato, Ralf Seidl
Electron-Ion Collider impact study on the tensor charge of the nucleon
12 pages, 6 figures, 1 table; minor changes; version to be published in PLB
Phys. Lett. B 816, 136255 (2021)
10.1016/j.physletb.2021.136255
JLAB-THY-21-3310
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this letter we study the impact of the Electron-Ion Collider (EIC) on the phenomenological extraction of the tensor charge from a QCD global analysis of single transverse-spin asymmetries (SSAs). We generate EIC pseudo-data for the Collins effect in semi-inclusive deep-inelastic scattering for proton and $^{3\!}He$ beams across multiple center-of-mass energies. We find a significant reduction in the uncertainties for the up, down, and isovector tensor charges that will make their extraction from EIC data on SSAs as precise as current lattice QCD calculations. We also analyze the constraints placed by future data from the proposed SoLID experiment at Jefferson Lab, discuss its important complementary role to the EIC, and present the combined impact from both facilities.
[ { "created": "Fri, 15 Jan 2021 16:30:20 GMT", "version": "v1" }, { "created": "Wed, 17 Mar 2021 12:57:13 GMT", "version": "v2" }, { "created": "Wed, 31 Mar 2021 21:26:27 GMT", "version": "v3" } ]
2022-12-06
[ [ "Gamberg", "Leonard", "" ], [ "Kang", "Zhong-Bo", "" ], [ "Pitonyak", "Daniel", "" ], [ "Prokudin", "Alexei", "" ], [ "Sato", "Nobuo", "" ], [ "Seidl", "Ralf", "" ] ]
In this letter we study the impact of the Electron-Ion Collider (EIC) on the phenomenological extraction of the tensor charge from a QCD global analysis of single transverse-spin asymmetries (SSAs). We generate EIC pseudo-data for the Collins effect in semi-inclusive deep-inelastic scattering for proton and $^{3\!}He$ beams across multiple center-of-mass energies. We find a significant reduction in the uncertainties for the up, down, and isovector tensor charges that will make their extraction from EIC data on SSAs as precise as current lattice QCD calculations. We also analyze the constraints placed by future data from the proposed SoLID experiment at Jefferson Lab, discuss its important complementary role to the EIC, and present the combined impact from both facilities.
hep-ph/9604433
Bernd Schlei
R.M. Weiner
Bose Einstein Correlations and Quantum Field Theory
10 pages, Invited talk at the Second German-Polish Symposium, Zakopane 1995, to appear in the volume "New Ideas in the Theory of Fundamental Interactions", Acta Physica Polonica B, 1996, editors H.D.Doebner, M.Pawlowski, and R. Raczka
Acta Phys.Polon. B27 (1996) 2637-2648
null
null
hep-ph
null
It is shown that there exists an intimate relationship between Bose Einstein correlations and quantum field theory. On the one hand several essential aspects of BEC cannot be understood and even formulated without second quantization. On the other hand BEC can serve as a unique tool in the investigation of modern field theory and in particular of the standard model. Some new developments on this subject related to multiparticle production and squeezed states are also discussed.
[ { "created": "Mon, 29 Apr 1996 20:07:02 GMT", "version": "v1" } ]
2007-05-23
[ [ "Weiner", "R. M.", "" ] ]
It is shown that there exists an intimate relationship between Bose Einstein correlations and quantum field theory. On the one hand several essential aspects of BEC cannot be understood and even formulated without second quantization. On the other hand BEC can serve as a unique tool in the investigation of modern field theory and in particular of the standard model. Some new developments on this subject related to multiparticle production and squeezed states are also discussed.
0812.1698
Junjie Cao
Junjie Cao, Zhaoxia Heng, Lei Wu, Jin Min Yang
R-parity violating effects in top quark FCNC productions at LHC
version in PRD (discussions added)
Phys.Rev.D79:054003,2009
10.1103/PhysRevD.79.054003
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the minimal supersymmetric model the R-parity violating top quark interactions, which are so far weakly constrained, can induce various flavor-changing neutral-current (FCNC) productions for the top quark at the Large Hadron Collider (LHC). In this work we assume the presence of the B-violating couplings and examine their contributions to the FCNC productions proceeding through the parton processes cg -> t, gg -> t c_bar, cg -> t\gamma, cg -> t Z and cg -> t h. We find that all these processes can be greatly enhanced relative to the R-parity preserving predictions. In the parameter space allowed by current experiments, all the production channels except cg ->t h can reach the 3-sigma sensitivity, in contrast to the R-parity preserving case in which only cg -> t can reach the 3-sigma sensitivity.
[ { "created": "Tue, 9 Dec 2008 14:16:47 GMT", "version": "v1" }, { "created": "Sat, 7 Mar 2009 09:31:01 GMT", "version": "v2" } ]
2009-05-29
[ [ "Cao", "Junjie", "" ], [ "Heng", "Zhaoxia", "" ], [ "Wu", "Lei", "" ], [ "Yang", "Jin Min", "" ] ]
In the minimal supersymmetric model the R-parity violating top quark interactions, which are so far weakly constrained, can induce various flavor-changing neutral-current (FCNC) productions for the top quark at the Large Hadron Collider (LHC). In this work we assume the presence of the B-violating couplings and examine their contributions to the FCNC productions proceeding through the parton processes cg -> t, gg -> t c_bar, cg -> t\gamma, cg -> t Z and cg -> t h. We find that all these processes can be greatly enhanced relative to the R-parity preserving predictions. In the parameter space allowed by current experiments, all the production channels except cg ->t h can reach the 3-sigma sensitivity, in contrast to the R-parity preserving case in which only cg -> t can reach the 3-sigma sensitivity.
hep-ph/9807397
Alan M. Nathan
Alan M. Nathan (for the E97-108 Collaboration)
Real Compton Scattering at High Transverse Momentum Transfer
Contribution to the Jefferson Lab Workshop on Physics & Instrumentation with 6-12 GeV Beams; 4 pages, 3 figures
null
null
null
hep-ph
null
We discuss the physics motivation for a program of Real Compton Scattering on the proton in the regime where both the incident energy and the transverse momentum transfer are large. It is shown that such a program can test which of the various hard scattering mechanisms is dominant and can allow a measurement of a new generalized form factor that is sensitive to both the flavor and spin structure of the proton. It is further shown that the measurements are experimentally feasible using existing or already planned equipment up to incident energies of 12 GeV.
[ { "created": "Thu, 16 Jul 1998 17:21:05 GMT", "version": "v1" } ]
2007-05-23
[ [ "Nathan", "Alan M.", "", "for the E97-108 Collaboration" ] ]
We discuss the physics motivation for a program of Real Compton Scattering on the proton in the regime where both the incident energy and the transverse momentum transfer are large. It is shown that such a program can test which of the various hard scattering mechanisms is dominant and can allow a measurement of a new generalized form factor that is sensitive to both the flavor and spin structure of the proton. It is further shown that the measurements are experimentally feasible using existing or already planned equipment up to incident energies of 12 GeV.
1612.08415
Michael Florian Wondrak
Michael Florian Wondrak, Piero Nicolini and Marcus Bleicher
Planck scale black holes - Theory vs. observations
27 pages, 3 figures, talk given at Frontier Research in Astrophysics - II, 23-28 May 2016, Mondello (Palermo), Italy
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we present the status of the physics of Planck scale black holes with particular reference to their conjectured production in particle accelerator experiments at the terascale. After reviewing some open issues of fundamental interactions and introducing the physics in the large extra-dimensional scenario, we present the expected signatures left by a microscopic black hole in a particle detector. The final part of the paper is devoted to the latest experimental bounds on the sought black hole signals.
[ { "created": "Mon, 26 Dec 2016 17:24:24 GMT", "version": "v1" }, { "created": "Tue, 3 Oct 2017 18:54:56 GMT", "version": "v2" } ]
2017-10-05
[ [ "Wondrak", "Michael Florian", "" ], [ "Nicolini", "Piero", "" ], [ "Bleicher", "Marcus", "" ] ]
In this paper we present the status of the physics of Planck scale black holes with particular reference to their conjectured production in particle accelerator experiments at the terascale. After reviewing some open issues of fundamental interactions and introducing the physics in the large extra-dimensional scenario, we present the expected signatures left by a microscopic black hole in a particle detector. The final part of the paper is devoted to the latest experimental bounds on the sought black hole signals.
1007.1537
Suratna Das
Kaushik Bhattacharya and Suratna Das
Thermodynamics of the Pauli oscillators and Lee-Wick partners of the Standard Model particles
8 pages, 2 figures, For a more detailed version refer to arXiv:1108.0483
null
null
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The present article is about the statistical mechanics of non-trivial field configurations. The non-trivial fields arise from the negative sign of the commutators and the anticommutators of the bosonic and fermionic field excitations. These kinds of fields were previously studied by Pauli and Lee and Wick. The thermal distribution function of the above mentioned fields are calculated in the article and using the thermal distribution functions the energy density, pressure and entropy density of the non-trivial field configurations are found out. The results match exactly with a previous calculation done by Fornal et. al. for higher derivative Lee-Wick theories showing a deeper similarity with the earlier work. It is assumed that such kinds of non-trivial fields may have existed in the early universe and may have some cosmological relevance.
[ { "created": "Fri, 9 Jul 2010 09:23:46 GMT", "version": "v1" }, { "created": "Wed, 3 Aug 2011 08:37:09 GMT", "version": "v2" } ]
2011-08-04
[ [ "Bhattacharya", "Kaushik", "" ], [ "Das", "Suratna", "" ] ]
The present article is about the statistical mechanics of non-trivial field configurations. The non-trivial fields arise from the negative sign of the commutators and the anticommutators of the bosonic and fermionic field excitations. These kinds of fields were previously studied by Pauli and Lee and Wick. The thermal distribution function of the above mentioned fields are calculated in the article and using the thermal distribution functions the energy density, pressure and entropy density of the non-trivial field configurations are found out. The results match exactly with a previous calculation done by Fornal et. al. for higher derivative Lee-Wick theories showing a deeper similarity with the earlier work. It is assumed that such kinds of non-trivial fields may have existed in the early universe and may have some cosmological relevance.
2201.00315
Sergey Troshin
S.M. Troshin, N.E. Tyurin
Energy evolution of the overlap functions: increasing ratio of $\sigma_{el}(s)/\sigma_{tot}(s)$ and black ring emergence
14 pages, 2 figures, revised version accepted in J. Phys. G
2022 J. Phys. G: Nucl. Part. Phys. 49 115001
10.1088/1361-6471/ac8f60
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We analyse the two possible options of the energy dependency of the elastic and inelastic overlap functions. These correspond to saturation of the black disk limit (BEL effect) and to the unitarity saturation (REL effect) at $s\to\infty$. Relation of the REL effect to increase of the ratio $\sigma_{el}(s)/\sigma_{tot}(s)$ and emergence of black ring picture at the LHC is underlined.
[ { "created": "Sun, 2 Jan 2022 07:43:24 GMT", "version": "v1" }, { "created": "Mon, 31 Jan 2022 08:11:50 GMT", "version": "v2" }, { "created": "Tue, 6 Sep 2022 07:49:59 GMT", "version": "v3" } ]
2022-09-19
[ [ "Troshin", "S. M.", "" ], [ "Tyurin", "N. E.", "" ] ]
We analyse the two possible options of the energy dependency of the elastic and inelastic overlap functions. These correspond to saturation of the black disk limit (BEL effect) and to the unitarity saturation (REL effect) at $s\to\infty$. Relation of the REL effect to increase of the ratio $\sigma_{el}(s)/\sigma_{tot}(s)$ and emergence of black ring picture at the LHC is underlined.
2309.08336
Raghunath Sahoo
Aswathy Menon K R, Suraj Prasad, Sushanta Tripathy, Neelkamal Mallick, and Raghunath Sahoo
Investigating radial-flow-like effects via pseudorapidity and transverse spherocity dependence of particle production in pp collisions at the LHC
12 pages and 13 captioned figures. Submitted for publication
null
null
null
hep-ph hep-ex nucl-ex nucl-th
http://creativecommons.org/licenses/by-sa/4.0/
Recent observations of quark-gluon plasma (QGP) like signatures in high multiplicity proton-proton (pp) collisions, have compelled the heavy-ion physics community to re-examine the pp collisions for proper baseline studies. Event-shape-based studies in pp collisions have succeeded to a certain extent in identifying rare events mimicking such heavy-ion-like behaviour. In this manuscript, we incorporate PYTHIA8 to study radial flow-like signatures in pp collisions at $\sqrt{s} = 13$ TeV as a function of transverse spherocity and pseudo-rapidity. The pseudo-rapidity dependence would help understand the scientific community for future upgrades. At the same time, the transverse spherocity will serve its purpose of identifying soft-QCD-dominated events in small collision systems. We present the mean transverse momentum, particle ratios, and kinetic freezeout parameters as a function of transverse spherocity and pseudo-rapidity in pp collisions at $\sqrt{s}$ = 13 TeV using PYTHIA8. We observe that the isotropic events show enhanced radial-flow effects and jetty events show the absence of radial-flow-like effects. For the first time, we show the transverse spherocity and pseudorapidity dependence of partonic modification factor in pp collisions, which clearly shows that by choosing transverse spherocity one can directly probe the radial-flow-like effects in pp collisions at the LHC.
[ { "created": "Fri, 15 Sep 2023 11:45:44 GMT", "version": "v1" } ]
2023-09-18
[ [ "R", "Aswathy Menon K", "" ], [ "Prasad", "Suraj", "" ], [ "Tripathy", "Sushanta", "" ], [ "Mallick", "Neelkamal", "" ], [ "Sahoo", "Raghunath", "" ] ]
Recent observations of quark-gluon plasma (QGP) like signatures in high multiplicity proton-proton (pp) collisions, have compelled the heavy-ion physics community to re-examine the pp collisions for proper baseline studies. Event-shape-based studies in pp collisions have succeeded to a certain extent in identifying rare events mimicking such heavy-ion-like behaviour. In this manuscript, we incorporate PYTHIA8 to study radial flow-like signatures in pp collisions at $\sqrt{s} = 13$ TeV as a function of transverse spherocity and pseudo-rapidity. The pseudo-rapidity dependence would help understand the scientific community for future upgrades. At the same time, the transverse spherocity will serve its purpose of identifying soft-QCD-dominated events in small collision systems. We present the mean transverse momentum, particle ratios, and kinetic freezeout parameters as a function of transverse spherocity and pseudo-rapidity in pp collisions at $\sqrt{s}$ = 13 TeV using PYTHIA8. We observe that the isotropic events show enhanced radial-flow effects and jetty events show the absence of radial-flow-like effects. For the first time, we show the transverse spherocity and pseudorapidity dependence of partonic modification factor in pp collisions, which clearly shows that by choosing transverse spherocity one can directly probe the radial-flow-like effects in pp collisions at the LHC.
1009.4850
Alan R. White
Alan. R. White
Could a Weak Coupling Massless SU(5) Theory Underly the Standard Model S-Matrix?
Contributed to the Proceedings of the Gribov-80 Memorial Workshop (without the Appendix)
null
10.1142/9789814350198_0045
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The unitary Critical Pomeron connects to a unique massless left-handed SU(5) theory that, remarkably, might provide an unconventional underlying unification for the Standard Model. Multi-regge theory suggests the existence of a {\it bound-state high-energy S-Matrix} that replicates Standard Model states and interactions via massless fermion anomaly dynamics. Configurations of anomalous wee gauge boson reggeons play a vacuum-like role. All particles, including neutrinos, are bound-states with dynamical masses (there is no Higgs field) that are formed (in part) by anomaly poles. The contributing zero-momentum chirality transitions break the SU(5) symmetry to vector SU(3)xU(1) in the S-Matrix. The high-energy interactions are vector reggeon exchanges accompanied by wee boson sums (odd-signature for the strong interaction and even-signature for the electroweak interaction) that strongly enhance couplings. The very small SU(5) coupling, ~ 1/120, should be reflected in small (Majorana) neutrino masses. A color sextet quark sector, still to be discovered, produces both Dark Matter and Electroweak Symmetry Breaking. Anomaly color factors imply this sector could be produced at the LHC with large cross-sections, and would be definitively identified in double pomeron processes.
[ { "created": "Fri, 24 Sep 2010 14:26:34 GMT", "version": "v1" } ]
2017-08-23
[ [ "White", "Alan. R.", "" ] ]
The unitary Critical Pomeron connects to a unique massless left-handed SU(5) theory that, remarkably, might provide an unconventional underlying unification for the Standard Model. Multi-regge theory suggests the existence of a {\it bound-state high-energy S-Matrix} that replicates Standard Model states and interactions via massless fermion anomaly dynamics. Configurations of anomalous wee gauge boson reggeons play a vacuum-like role. All particles, including neutrinos, are bound-states with dynamical masses (there is no Higgs field) that are formed (in part) by anomaly poles. The contributing zero-momentum chirality transitions break the SU(5) symmetry to vector SU(3)xU(1) in the S-Matrix. The high-energy interactions are vector reggeon exchanges accompanied by wee boson sums (odd-signature for the strong interaction and even-signature for the electroweak interaction) that strongly enhance couplings. The very small SU(5) coupling, ~ 1/120, should be reflected in small (Majorana) neutrino masses. A color sextet quark sector, still to be discovered, produces both Dark Matter and Electroweak Symmetry Breaking. Anomaly color factors imply this sector could be produced at the LHC with large cross-sections, and would be definitively identified in double pomeron processes.
hep-ph/0703276
Marco Ruggieri
R. Gatto and M. Ruggieri
On the ground state of gapless two flavor color superconductors
16 pages, RevTe3X4 style
Phys.Rev.D75:114004,2007
10.1103/PhysRevD.75.114004
BARI-TH-567/07
hep-ph cond-mat.supr-con
null
This paper is devoted to the study of some aspects of the instability of two flavor color superconductive quark matter. We find that, beside color condensates, the Goldstone boson related to the breaking of $U(1)_A$ suffers of a velocity instability. We relate this wrong sign problem, which implies the existence of a Goldstone current in the ground state or of gluonic condensation, to the negative squared Meissner mass of the $8^{th}$ gluon in the g2SC phase. Moreover we investigate the Meissner masses of the gluons and the squared velocity of the Goldstone in the multiple plane wave LOFF states, arguing that in such phases both the chromo-magnetic instability and the velocity instability are most probably removed. We also do not expect Higgs instability in such multiple plane wave LOFF. The true vacuum of gapless two flavor superconductors is thus expected to be a multiple plane wave LOFF state.
[ { "created": "Mon, 26 Mar 2007 15:46:00 GMT", "version": "v1" }, { "created": "Thu, 17 May 2007 08:03:05 GMT", "version": "v2" } ]
2008-11-26
[ [ "Gatto", "R.", "" ], [ "Ruggieri", "M.", "" ] ]
This paper is devoted to the study of some aspects of the instability of two flavor color superconductive quark matter. We find that, beside color condensates, the Goldstone boson related to the breaking of $U(1)_A$ suffers of a velocity instability. We relate this wrong sign problem, which implies the existence of a Goldstone current in the ground state or of gluonic condensation, to the negative squared Meissner mass of the $8^{th}$ gluon in the g2SC phase. Moreover we investigate the Meissner masses of the gluons and the squared velocity of the Goldstone in the multiple plane wave LOFF states, arguing that in such phases both the chromo-magnetic instability and the velocity instability are most probably removed. We also do not expect Higgs instability in such multiple plane wave LOFF. The true vacuum of gapless two flavor superconductors is thus expected to be a multiple plane wave LOFF state.
hep-ph/0402113
Yukihiro Mimura
Bhaskar Dutta, Yukihiro Mimura, R.N. Mohapatra
CKM CP Violation in a Minimal SO(10) Model for Neutrinos and Its Implications
26 pages, 9 figures
Phys.Rev. D69 (2004) 115014
10.1103/PhysRevD.69.115014
UMD-PP-04-019
hep-ph
null
A minimal supersymmetric SO(10) model with one {\bf 10} and one {\bf 126} Higgs superfield has recently been shown to predict all neutrino mixings as well as the solar mass difference squared in agreement with observations. Two assumptions critical to the predictivity and success of the model are that: (i) the superpotential includes only renormalizable terms, thereby limiting the number of free parameters and (ii) the triplet term in the type II seesaw formula for neutrino mass dominates, leading to the sum rule M_nu = c(M_d - M_e) that is responsible for large mixings. However, CKM CP phase is constrained to be in the second or third quadrant requiring a significant non-CKM component to CP violation to explain observations. We revisit this issue using type I seesaw formula for neutrino masses and obtain the following results: (i) we show that the above sumrule responsible for large mixing angles can also emerge in type I seesaw models; the detailed predictions are however not compatible with present data for any choice of CP phases. (ii) We then show that addition of a nonrenormalizable term restores compatibility with neutrino data and CKM CP violation both in type I and type II cases. We further find that (iii) the MSSM parameter tan beta > 30 in the type I model and (iv) lepton flavor violation and lepton electric dipole moments which are accessible to proposed experiments in both type I and type II models. We also discuss the unification of the gauge couplings in type I model which requires an intermediate scale.
[ { "created": "Tue, 10 Feb 2004 22:15:32 GMT", "version": "v1" } ]
2009-11-10
[ [ "Dutta", "Bhaskar", "" ], [ "Mimura", "Yukihiro", "" ], [ "Mohapatra", "R. N.", "" ] ]
A minimal supersymmetric SO(10) model with one {\bf 10} and one {\bf 126} Higgs superfield has recently been shown to predict all neutrino mixings as well as the solar mass difference squared in agreement with observations. Two assumptions critical to the predictivity and success of the model are that: (i) the superpotential includes only renormalizable terms, thereby limiting the number of free parameters and (ii) the triplet term in the type II seesaw formula for neutrino mass dominates, leading to the sum rule M_nu = c(M_d - M_e) that is responsible for large mixings. However, CKM CP phase is constrained to be in the second or third quadrant requiring a significant non-CKM component to CP violation to explain observations. We revisit this issue using type I seesaw formula for neutrino masses and obtain the following results: (i) we show that the above sumrule responsible for large mixing angles can also emerge in type I seesaw models; the detailed predictions are however not compatible with present data for any choice of CP phases. (ii) We then show that addition of a nonrenormalizable term restores compatibility with neutrino data and CKM CP violation both in type I and type II cases. We further find that (iii) the MSSM parameter tan beta > 30 in the type I model and (iv) lepton flavor violation and lepton electric dipole moments which are accessible to proposed experiments in both type I and type II models. We also discuss the unification of the gauge couplings in type I model which requires an intermediate scale.
1911.11537
Jose Illana
Jose I. Illana and Jose M. Perez-Poyatos
The full lepton flavor of little Higgs
10 pages, 4 figures; presented at the XLIII International Conference of Theoretical Physics "Matter to the Deepest'', Katowice, Poland, September 1-6, 2019
null
10.5506/APhysPolB.50.1781
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The little Higgs model with T-parity, compatible with electroweak precision constraints, introduces new flavor-mixing sources, some of which had been ignored until recently. They are reviewed here, showing that their influence does not only enrich the phenomenology of flavor-changing processes but is also needed to render finite one-loop amplitudes.
[ { "created": "Tue, 26 Nov 2019 13:59:48 GMT", "version": "v1" } ]
2020-02-19
[ [ "Illana", "Jose I.", "" ], [ "Perez-Poyatos", "Jose M.", "" ] ]
The little Higgs model with T-parity, compatible with electroweak precision constraints, introduces new flavor-mixing sources, some of which had been ignored until recently. They are reviewed here, showing that their influence does not only enrich the phenomenology of flavor-changing processes but is also needed to render finite one-loop amplitudes.