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hep-ph/9706441
postDr.
Hsiang-nan Li and B. Tseng
Nonfactorizable soft gluons in nonleptonic heavy meson decays
21 pages, LaTeX
Phys.Rev.D57:443-451,1998
10.1103/PhysRevD.57.443
NCKU-HEP-97-02,NTU-TH-97-07
hep-ph
null
We include nonfactorizable soft gluon corrections into the perturbative QCD formalism for exclusive nonleptonic heavy meson decays, which combines factorization theorems and effective field theory. These corrections are classified according to their color structures, and exponentiated separately to complete the Sudakov resummation up to next-to-leading logarithms. The nonfactorizable contributions in nonleptonic decays are clearly identified in our formalism, and found to be positive for bottom decays and negative for charm decays. Our analysis confirms that the large-$N_c$ approximaton is applicable to charm decays, but not to bottom decays, consistent with the phenomenological implications of experimental data. The comparision of our predictions with those from QCD sum rules is also made.
[ { "created": "Sat, 21 Jun 1997 16:15:13 GMT", "version": "v1" } ]
2011-07-19
[ [ "Li", "Hsiang-nan", "" ], [ "Tseng", "B.", "" ] ]
We include nonfactorizable soft gluon corrections into the perturbative QCD formalism for exclusive nonleptonic heavy meson decays, which combines factorization theorems and effective field theory. These corrections are classified according to their color structures, and exponentiated separately to complete the Sudakov resummation up to next-to-leading logarithms. The nonfactorizable contributions in nonleptonic decays are clearly identified in our formalism, and found to be positive for bottom decays and negative for charm decays. Our analysis confirms that the large-$N_c$ approximaton is applicable to charm decays, but not to bottom decays, consistent with the phenomenological implications of experimental data. The comparision of our predictions with those from QCD sum rules is also made.
hep-ph/0304251
G. X. Peng
G.X.Peng, U.Lombardo, M.Loewe, H.C.Chiang, and P.Z.Ning
Chiral Condensates in Quark and nuclear Matter
12 pages, 7 figures, revtex4 style
Int.J.Mod.Phys. A18 (2003) 3151-3174
10.1142/S0217751X03014046
null
hep-ph
null
We present a novel treatment for calculating the in-medium quark condensates. The advantage of this approach is that one does not need to make further assumptions on the derivatives of model parameters with respect to the quark current mass. The normally accepted model-independent result in nuclear matter is naturally reproduced. The change of the quark condensate induced by interactions depends on the incompressibility of nuclear matter. When it is greater than 260 MeV, the density at which the condensate vanishes is higher than that from the linear extrapolation. For the chiral condensate in quark matter, a similar model-independent linear behavior is found at lower densities, which means that the decreasing speed of the condensate in quark matter is merely half of that in nuclear matter if the pion-nucleon sigma commutator is six times the average current mass of u and d quarks. The modification due to QCD-like interactions is found to slow the decreasing speed of the condensate, compared with the linear extrapolation.
[ { "created": "Sun, 27 Apr 2003 04:05:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Peng", "G. X.", "" ], [ "Lombardo", "U.", "" ], [ "Loewe", "M.", "" ], [ "Chiang", "H. C.", "" ], [ "Ning", "P. Z.", "" ] ]
We present a novel treatment for calculating the in-medium quark condensates. The advantage of this approach is that one does not need to make further assumptions on the derivatives of model parameters with respect to the quark current mass. The normally accepted model-independent result in nuclear matter is naturally reproduced. The change of the quark condensate induced by interactions depends on the incompressibility of nuclear matter. When it is greater than 260 MeV, the density at which the condensate vanishes is higher than that from the linear extrapolation. For the chiral condensate in quark matter, a similar model-independent linear behavior is found at lower densities, which means that the decreasing speed of the condensate in quark matter is merely half of that in nuclear matter if the pion-nucleon sigma commutator is six times the average current mass of u and d quarks. The modification due to QCD-like interactions is found to slow the decreasing speed of the condensate, compared with the linear extrapolation.
hep-ph/9507276
Evan Keith
T. V. Duong, E. Keith, Hisashi Kikuchi, and Ernest Ma
Decay of Z into Two Light Higgs Bosons
10 pages, LaTex, figures available upon request to evan@ucrphh.ucr.edu
Phys.Rev. D52 (1995) 5045-5049
10.1103/PhysRevD.52.5045
UCRHEP-T146
hep-ph
null
If the standard electroweak gauge model is extended to include two or more Higgs doublets, there may be a neutral Higgs boson $h$ which is light (with a mass of say 10 GeV) but the $hZZ$ coupling is suppressed so that it has so far escaped experimental detection. However, the effective $hhZZ$ coupling is generally unsuppressed, hence the decay of Z into two light Higgs bosons plus a fermion-antifermion pair may have an observable branching fraction, especially if $h$ decays invisibly as for example in the recently proposed doublet Majoron model.
[ { "created": "Mon, 10 Jul 1995 21:03:25 GMT", "version": "v1" } ]
2016-09-01
[ [ "Duong", "T. V.", "" ], [ "Keith", "E.", "" ], [ "Kikuchi", "Hisashi", "" ], [ "Ma", "Ernest", "" ] ]
If the standard electroweak gauge model is extended to include two or more Higgs doublets, there may be a neutral Higgs boson $h$ which is light (with a mass of say 10 GeV) but the $hZZ$ coupling is suppressed so that it has so far escaped experimental detection. However, the effective $hhZZ$ coupling is generally unsuppressed, hence the decay of Z into two light Higgs bosons plus a fermion-antifermion pair may have an observable branching fraction, especially if $h$ decays invisibly as for example in the recently proposed doublet Majoron model.
hep-ph/0606302
Peihong Gu
Pei-Hong Gu, He Zhang, Shun Zhou
A Minimal Type II Seesaw Model
5 pages, 4 figures, some points clarified, useful references added, to appear in Phys. Rev. D
Phys.Rev.D74:076002,2006
10.1103/PhysRevD.74.076002
null
hep-ph
null
We propose a minimal type II seesaw model by introducing only one right-handed neutrino besides the $SU(2)_{L}$ triplet Higgs to the standard model. In the usual type II seesaw models with several right-handed neutrinos, the contributions of the right-handed neutrinos and the triplet Higgs to the CP asymmetry, which stems from the decay of the lightest right-handed neutrino, are proportional to their respective contributions to the light neutrino mass matrix. However, in our minimal type II seesaw model, this CP asymmetry is just given by the one-loop vertex correction involving the triplet Higgs, even though the contribution of the triplet Higgs does not dominate the light neutrino masses. For illustration, the Fritzsch-type lepton mass matrices are considered.
[ { "created": "Thu, 29 Jun 2006 14:05:51 GMT", "version": "v1" }, { "created": "Sat, 1 Jul 2006 01:57:23 GMT", "version": "v2" }, { "created": "Fri, 29 Sep 2006 07:52:26 GMT", "version": "v3" } ]
2008-11-26
[ [ "Gu", "Pei-Hong", "" ], [ "Zhang", "He", "" ], [ "Zhou", "Shun", "" ] ]
We propose a minimal type II seesaw model by introducing only one right-handed neutrino besides the $SU(2)_{L}$ triplet Higgs to the standard model. In the usual type II seesaw models with several right-handed neutrinos, the contributions of the right-handed neutrinos and the triplet Higgs to the CP asymmetry, which stems from the decay of the lightest right-handed neutrino, are proportional to their respective contributions to the light neutrino mass matrix. However, in our minimal type II seesaw model, this CP asymmetry is just given by the one-loop vertex correction involving the triplet Higgs, even though the contribution of the triplet Higgs does not dominate the light neutrino masses. For illustration, the Fritzsch-type lepton mass matrices are considered.
hep-ph/9508375
Sato Masatoshi
Masatoshi Sato
Shapes of Cosmic Strings and Baryon Number Violation
13 pages, LaTeX
Phys.Lett. B376 (1996) 41-47
10.1016/0370-2693(96)00271-7
KUNS-1349 HE(TH)95/09
hep-ph astro-ph
null
The relation between shapes of cosmic string and baryon number violation is investigated. If there exist fermionic zero modes on the string, using bosonization technique, it is possible to obtain the effective action which describes the fermion coupled to the arbitrarily shaped cosmic string. The relation between baryon number and the sum of the writhing number and linking number of the cosmic strings is rederived. Baryons are created on the strings as the shapes of the cosmic strings change. Furthermore we discuss implications of this baryon number violating process to baryogenesis.
[ { "created": "Sat, 26 Aug 1995 12:26:54 GMT", "version": "v1" } ]
2009-10-28
[ [ "Sato", "Masatoshi", "" ] ]
The relation between shapes of cosmic string and baryon number violation is investigated. If there exist fermionic zero modes on the string, using bosonization technique, it is possible to obtain the effective action which describes the fermion coupled to the arbitrarily shaped cosmic string. The relation between baryon number and the sum of the writhing number and linking number of the cosmic strings is rederived. Baryons are created on the strings as the shapes of the cosmic strings change. Furthermore we discuss implications of this baryon number violating process to baryogenesis.
1812.11186
Raymond Co
Raymond T. Co, Eric Gonzalez, and Keisuke Harigaya
Axion Misalignment Driven to the Bottom
16 pages, 2 figures; v2: minor changes and references added, matches journal version
null
10.1007/JHEP05(2019)162
LCTP-18-34
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Several theoretical motivations point to ultralight QCD axions with large decay constants $f_a \simeq \mathcal{O}(10^{16}-10^{17})$ GeV, to which experimental proposals are dedicated. This regime is known to face the problem of overproduction of axion dark matter from the misalignment mechanism unless the misalignment angle $\theta_{\rm mis}$ is as small as $\mathcal{O}(10^{-3}-10^{-4})$, which is generally considered a fine-tuning problem. We investigate a dynamical explanation for a small $\theta_{\rm mis}$. The axion mass arises from strong dynamics and may be sufficiently enhanced by early dynamics so as to overcome Hubble friction and drive the field value to the bottom of the potential long before the QCD phase transition. Together with an approximate CP symmetry in the theory, this minimum is very closely related to today's value and thus $\theta_{\rm mis}$ can automatically be well under unity. Owing to such efficient relaxation, the isocurvature perturbations are essentially damped. As an existence proof, using supersymmetric theories we illustrate that the Higgs coupling with the inflaton energy can successfully achieve this axion damping in a consistent inflationary cosmology.
[ { "created": "Fri, 28 Dec 2018 19:00:01 GMT", "version": "v1" }, { "created": "Fri, 31 May 2019 13:39:55 GMT", "version": "v2" } ]
2019-06-26
[ [ "Co", "Raymond T.", "" ], [ "Gonzalez", "Eric", "" ], [ "Harigaya", "Keisuke", "" ] ]
Several theoretical motivations point to ultralight QCD axions with large decay constants $f_a \simeq \mathcal{O}(10^{16}-10^{17})$ GeV, to which experimental proposals are dedicated. This regime is known to face the problem of overproduction of axion dark matter from the misalignment mechanism unless the misalignment angle $\theta_{\rm mis}$ is as small as $\mathcal{O}(10^{-3}-10^{-4})$, which is generally considered a fine-tuning problem. We investigate a dynamical explanation for a small $\theta_{\rm mis}$. The axion mass arises from strong dynamics and may be sufficiently enhanced by early dynamics so as to overcome Hubble friction and drive the field value to the bottom of the potential long before the QCD phase transition. Together with an approximate CP symmetry in the theory, this minimum is very closely related to today's value and thus $\theta_{\rm mis}$ can automatically be well under unity. Owing to such efficient relaxation, the isocurvature perturbations are essentially damped. As an existence proof, using supersymmetric theories we illustrate that the Higgs coupling with the inflaton energy can successfully achieve this axion damping in a consistent inflationary cosmology.
1310.0157
Sadaharu Uehara
Sadaharu Uehara
TREPS: A Monte-Carlo Event Generator for Two-photon Processes at $e^+e^-$ Colliders using an Equivalent Photon Approximation
16 pages, 5 figures. Reprint edition of KEK Report 96-11 published in 1996. A memo for the upgraded version TREPS2 written in the same year is merged as an appendix
null
null
KEK Report 96-11
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A description and the use of an event-generator code for two-photon processes at e+e- colliders, TREPS, are presented. This program uses an equivalent photon approximation in which the virtuality of photons is taken into account. It is applicable to various processes by specifying a combination of final-state particles and the angular distributions among them. A comparison of the results with those from other programs is also given.
[ { "created": "Tue, 1 Oct 2013 06:59:57 GMT", "version": "v1" } ]
2013-10-02
[ [ "Uehara", "Sadaharu", "" ] ]
A description and the use of an event-generator code for two-photon processes at e+e- colliders, TREPS, are presented. This program uses an equivalent photon approximation in which the virtuality of photons is taken into account. It is applicable to various processes by specifying a combination of final-state particles and the angular distributions among them. A comparison of the results with those from other programs is also given.
2201.02417
Stefan Kluth
S. Kluth
$m_b(m_Z)$ revisited with Zedometry
9 pages, 1 figure, version accepted by Eur. J. Phys C
Eur. Phys. J. C 82 (2022) 240
10.1140/epjc/s10052-022-10219-x
MPP-2022-3
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Precision measurements of $Z^0$ boson properties could enable a determination of the mass of the b quark at the scale of the $Z^0$ boson mass $m_b(m_Z)$. The dependence of Standard Model predictions on the b quark mass using the program Gfitter is studied. The precision of the currently available measurements by the LEP experiments and SLD, together with measurements from the LHC experiments of the mass of the top quark and the Higgs boson, is not sufficient for a relevant measurement. The predicted precision of $Z^0$ boson resonance measurements at future $e^+e^-$ colliders will allow a competitive determination of $m_b(m_Z)$.
[ { "created": "Fri, 7 Jan 2022 12:07:52 GMT", "version": "v1" }, { "created": "Thu, 20 Jan 2022 14:17:09 GMT", "version": "v2" }, { "created": "Thu, 24 Mar 2022 12:00:55 GMT", "version": "v3" } ]
2022-03-25
[ [ "Kluth", "S.", "" ] ]
Precision measurements of $Z^0$ boson properties could enable a determination of the mass of the b quark at the scale of the $Z^0$ boson mass $m_b(m_Z)$. The dependence of Standard Model predictions on the b quark mass using the program Gfitter is studied. The precision of the currently available measurements by the LEP experiments and SLD, together with measurements from the LHC experiments of the mass of the top quark and the Higgs boson, is not sufficient for a relevant measurement. The predicted precision of $Z^0$ boson resonance measurements at future $e^+e^-$ colliders will allow a competitive determination of $m_b(m_Z)$.
0705.4059
Alejandra Melfo
Alejandra Melfo
Grand Unification with and without Supersymmetry
Talk given at the VI SILAFAE, Puerto Vallarta, Mexico, November 2006
AIPConf.Proc.917:252-259,2007
10.1063/1.2751964
null
hep-ph
null
Grand Unified Theories based on the group SO(10) generically provide interesting and testable relations between the charged fermions and neutrino sector masses and mixings. In the light of the recent neutrino data, we reexamine these relations both in supersymmetric and non-supersymmetric models, and give a brief review of their present status.
[ { "created": "Mon, 28 May 2007 15:56:05 GMT", "version": "v1" } ]
2008-11-26
[ [ "Melfo", "Alejandra", "" ] ]
Grand Unified Theories based on the group SO(10) generically provide interesting and testable relations between the charged fermions and neutrino sector masses and mixings. In the light of the recent neutrino data, we reexamine these relations both in supersymmetric and non-supersymmetric models, and give a brief review of their present status.
0910.4457
Florian Hebenstreit
Florian Hebenstreit, Reinhard Alkofer, Gerald V. Dunne, Holger Gies
Quantum statistics effect in Schwinger pair production in short laser pulses
5 pages, 2 figuers. Talk given by F.H. at the Ninth Conference on Quantum Field Theory under the Influence of External Conditions, 21-25 September 2009, Oklahoma, USA
null
10.1142/9789814289931_0062
null
hep-ph hep-th physics.optics
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate non-perturbative pair production from vacuum (the Schwinger effect) in the focal region of two counter-propagating, ultra-short laser pulses with sub-cycle structure. We use the quantum kinetic formulation to calculate the momentum spectrum of created particles and show the extreme sensitivity to the laser frequency $\omega$, the pulse length $\tau$ and the carrier-envelope absolute phase $\phi$. We apply this formalism to both fermions and bosons to illustrate the influence of quantum statistics in this type of electric background field.
[ { "created": "Fri, 23 Oct 2009 08:16:10 GMT", "version": "v1" } ]
2017-08-23
[ [ "Hebenstreit", "Florian", "" ], [ "Alkofer", "Reinhard", "" ], [ "Dunne", "Gerald V.", "" ], [ "Gies", "Holger", "" ] ]
We investigate non-perturbative pair production from vacuum (the Schwinger effect) in the focal region of two counter-propagating, ultra-short laser pulses with sub-cycle structure. We use the quantum kinetic formulation to calculate the momentum spectrum of created particles and show the extreme sensitivity to the laser frequency $\omega$, the pulse length $\tau$ and the carrier-envelope absolute phase $\phi$. We apply this formalism to both fermions and bosons to illustrate the influence of quantum statistics in this type of electric background field.
1805.05214
Eugenio Megias
E. Megias, E. Ruiz Arriola, L.L. Salcedo
Thermal correlators in the hadron resonance gas: a dual Hagedorn distance
6 pages, 1 figure. Talk given by E.Megias at Excited QCD 2018, 11-15 March 2018, Kopaonik, Serbia
null
null
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Fluctuations and correlations of conserved quantities in the confined phase of QCD are a viable way to characterize the existence of exotic and missing states with given quantum numbers in the hadronic spectrum. We study a realization of the Hadron Resonance Gas model in the light quark (uds) flavor sector of QCD to study the fluctuations and static correlators of electric charge, baryon number and strangeness. It is also conjectured an interesting duality between the correlators at zero temperature, and the fluctuations of integrated quantities at low temperatures, leading to the appearance of a dual Hagedorn distance for the former.
[ { "created": "Mon, 14 May 2018 15:06:22 GMT", "version": "v1" } ]
2018-05-15
[ [ "Megias", "E.", "" ], [ "Arriola", "E. Ruiz", "" ], [ "Salcedo", "L. L.", "" ] ]
Fluctuations and correlations of conserved quantities in the confined phase of QCD are a viable way to characterize the existence of exotic and missing states with given quantum numbers in the hadronic spectrum. We study a realization of the Hadron Resonance Gas model in the light quark (uds) flavor sector of QCD to study the fluctuations and static correlators of electric charge, baryon number and strangeness. It is also conjectured an interesting duality between the correlators at zero temperature, and the fluctuations of integrated quantities at low temperatures, leading to the appearance of a dual Hagedorn distance for the former.
2401.15698
Dmitry V. Naumov
Vladimir Allakhverdian and Dmitry V. Naumov
Infinite Series Solution of the Time-Dependent Radiative Transfer Equation in Anisotropically Scattering Media
null
Journal of Quantitative Spectroscopy & Radiative Transfer 326 (2024) 109126
10.1016/j.jqsrt.2024.109126
null
hep-ph math-ph math.MP physics.optics
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We solve the radiative transfer equation (RTE) in anisotropically scattering media as an infinite series. Each series term represents a distinct number of scattering events, with analytical solutions derived for zero and single scattering. Higher-order corrections are addressed through numerical calculations or approximations. The RTE solution corresponds to Monte Carlo sampling of photon trajectories with fixed start and end points. Validated against traditional Monte Carlo simulations, featuring random end points, our solution demonstrates enhanced efficiency for both anisotropic and isotropic scattering functions, significantly reducing computational time and resources. The advantage of our method over Monte Carlo simulations varies with the position of interest and the asymmetry of light scattering, but it is typically orders of magnitude faster while achieving the same level of accuracy. The exploitation of hidden symmetries further accelerates our numerical calculations, enhancing the method's overall efficiency. In addition, we extend our analysis to the first and second moments of the photon's flux, elucidating the transition between transport and diffusive regimes.
[ { "created": "Sun, 28 Jan 2024 16:50:02 GMT", "version": "v1" }, { "created": "Tue, 23 Jul 2024 18:48:42 GMT", "version": "v2" } ]
2024-07-25
[ [ "Allakhverdian", "Vladimir", "" ], [ "Naumov", "Dmitry V.", "" ] ]
We solve the radiative transfer equation (RTE) in anisotropically scattering media as an infinite series. Each series term represents a distinct number of scattering events, with analytical solutions derived for zero and single scattering. Higher-order corrections are addressed through numerical calculations or approximations. The RTE solution corresponds to Monte Carlo sampling of photon trajectories with fixed start and end points. Validated against traditional Monte Carlo simulations, featuring random end points, our solution demonstrates enhanced efficiency for both anisotropic and isotropic scattering functions, significantly reducing computational time and resources. The advantage of our method over Monte Carlo simulations varies with the position of interest and the asymmetry of light scattering, but it is typically orders of magnitude faster while achieving the same level of accuracy. The exploitation of hidden symmetries further accelerates our numerical calculations, enhancing the method's overall efficiency. In addition, we extend our analysis to the first and second moments of the photon's flux, elucidating the transition between transport and diffusive regimes.
1108.2957
Steffen Schumann
Steffen Schumann, Adrien Renaud and Dirk Zerwas
Hadronically decaying color-adjoint scalars at the LHC
15 pages, 10 figures
null
10.1007/JHEP09(2011)074
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the phenomenology of the pair-production of scalar color-octet electroweak singlet states at the LHC. Such states appear in many extensions of the Standard Model. They can be pair-produced copiously at the LHC and will signal themselves as resonances in multijet final states. Beyond the QCD pair-production process we consider a vectorlike confinement scenario with an additional color-octet vector state. These vector particles can be produced in the s-channel and through their decay contribute to the scalar pair production. We point out the differences between the two hypotheses and device a strategy to distinguish them.
[ { "created": "Mon, 15 Aug 2011 09:35:16 GMT", "version": "v1" } ]
2015-05-30
[ [ "Schumann", "Steffen", "" ], [ "Renaud", "Adrien", "" ], [ "Zerwas", "Dirk", "" ] ]
We study the phenomenology of the pair-production of scalar color-octet electroweak singlet states at the LHC. Such states appear in many extensions of the Standard Model. They can be pair-produced copiously at the LHC and will signal themselves as resonances in multijet final states. Beyond the QCD pair-production process we consider a vectorlike confinement scenario with an additional color-octet vector state. These vector particles can be produced in the s-channel and through their decay contribute to the scalar pair production. We point out the differences between the two hypotheses and device a strategy to distinguish them.
1906.10903
Sreeraj Sreedharan Nair
Chandan Mondal, Asmita Mukherjee and Sreeraj Nair
Double parton distributions for a positronium-like bound state using light-front wave functions
16 pages, 5 figures
Phys. Rev. D 100, 094002 (2019)
10.1103/PhysRevD.100.094002
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the double parton distributions (DPDs) for a positronium-like bound state using light-front QED. We incorporate the higher Fock three particle component of the state, that includes a photon. We obtain the overlap representation of the DPDs in terms of the three-particle light-front wave functions (LFWFs). Our calculation explores the correlations between the momentum fractions of the particles probed and the transverse distance between them, without any assumption of factorization between them. We also investigate the behavior of the DPDs near the kinematical boundary when the sum of the momentum fractions is close to one.
[ { "created": "Wed, 26 Jun 2019 08:16:02 GMT", "version": "v1" } ]
2019-11-06
[ [ "Mondal", "Chandan", "" ], [ "Mukherjee", "Asmita", "" ], [ "Nair", "Sreeraj", "" ] ]
We investigate the double parton distributions (DPDs) for a positronium-like bound state using light-front QED. We incorporate the higher Fock three particle component of the state, that includes a photon. We obtain the overlap representation of the DPDs in terms of the three-particle light-front wave functions (LFWFs). Our calculation explores the correlations between the momentum fractions of the particles probed and the transverse distance between them, without any assumption of factorization between them. We also investigate the behavior of the DPDs near the kinematical boundary when the sum of the momentum fractions is close to one.
hep-ph/0408234
Shi-Lin Zhu
Yuan-Ben Dai, Chun Liu, Y.-R. Liu, Shi-Lin Zhu
Possible Interpretations of $D_{sJ}^+(2632)$ If It Really Exists
null
JHEP0411:043,2004
10.1088/1126-6708/2004/11/043
null
hep-ph hep-ex hep-lat nucl-th
null
We analyze various possible interpretations of the narrow state $D_{sJ}^+(2632)$ observed by SELEX Collaboration recently, which lies above threshold and has abnormal decay pattern. These interpretations include: (1) several versions of tetraquarks; (2) conventional $c\bar s$ meson such as the first radial excitation of $D_s(2112)$ with abnormally large SU(3) symmetry breaking; (3) conventional $c\bar s$ meson with abnormally large $\eta_1$ coupling; (4) heavy hybrid meson. We discuss the physical implications of each interpretation. For example, if the existence of $D_{sJ}^+(2632)$ is confirmed as the first radial excitation of $D_s(2112)$ by other experiments, it will be helpful to look for (1) its SU(3) flavor partners $D_{J}^{0,+}(2530)$; (2) its B-meson analogues $B_{J}^{0,+}(5840), B_{sJ}^+(5940)$; (3) S-wave two pion decay modes.
[ { "created": "Sun, 22 Aug 2004 03:07:07 GMT", "version": "v1" } ]
2008-11-26
[ [ "Dai", "Yuan-Ben", "" ], [ "Liu", "Chun", "" ], [ "Liu", "Y. -R.", "" ], [ "Zhu", "Shi-Lin", "" ] ]
We analyze various possible interpretations of the narrow state $D_{sJ}^+(2632)$ observed by SELEX Collaboration recently, which lies above threshold and has abnormal decay pattern. These interpretations include: (1) several versions of tetraquarks; (2) conventional $c\bar s$ meson such as the first radial excitation of $D_s(2112)$ with abnormally large SU(3) symmetry breaking; (3) conventional $c\bar s$ meson with abnormally large $\eta_1$ coupling; (4) heavy hybrid meson. We discuss the physical implications of each interpretation. For example, if the existence of $D_{sJ}^+(2632)$ is confirmed as the first radial excitation of $D_s(2112)$ by other experiments, it will be helpful to look for (1) its SU(3) flavor partners $D_{J}^{0,+}(2530)$; (2) its B-meson analogues $B_{J}^{0,+}(5840), B_{sJ}^+(5940)$; (3) S-wave two pion decay modes.
1304.8037
Masaya Kohda
Kai-Feng Chen, Wei-Shu Hou, Chung Kao, Masaya Kohda
When the Higgs meets the Top: Search for t --> ch^0 at the LHC
5 pages, 3 figures, version to appear in PLB
null
10.1016/j.physletb.2013.07.060
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The newly discovered "Higgs" boson h^0, being lighter than the top quark t, opens up new probes for flavor and mass generation. In the general two Higgs doublet model, new ct, cc and tt Yukawa couplings could modify h^0 properties. If t --> ch^0 occurs at the percent level, the observed ZZ^* and \gamma\gamma signal events may have accompanying cbW activity coming from t\bar{t} feeddown. We suggest that t --> ch^0 can be searched for via h^0 --> ZZ^*, \gamma\gamma, WW^* and b\bar{b}, perhaps even \tau^+\tau^- modes in t\bar{t} events. Existing data might be able to reveal some clues for t --> ch^0 signature, or push the branching ratio B(t --> ch^0) down to below the percent level.
[ { "created": "Tue, 30 Apr 2013 15:35:11 GMT", "version": "v1" }, { "created": "Mon, 29 Jul 2013 17:31:36 GMT", "version": "v2" } ]
2015-06-15
[ [ "Chen", "Kai-Feng", "" ], [ "Hou", "Wei-Shu", "" ], [ "Kao", "Chung", "" ], [ "Kohda", "Masaya", "" ] ]
The newly discovered "Higgs" boson h^0, being lighter than the top quark t, opens up new probes for flavor and mass generation. In the general two Higgs doublet model, new ct, cc and tt Yukawa couplings could modify h^0 properties. If t --> ch^0 occurs at the percent level, the observed ZZ^* and \gamma\gamma signal events may have accompanying cbW activity coming from t\bar{t} feeddown. We suggest that t --> ch^0 can be searched for via h^0 --> ZZ^*, \gamma\gamma, WW^* and b\bar{b}, perhaps even \tau^+\tau^- modes in t\bar{t} events. Existing data might be able to reveal some clues for t --> ch^0 signature, or push the branching ratio B(t --> ch^0) down to below the percent level.
hep-ph/9509319
Kim Yeong Gyun
Jae Kwan Kim, Yeong Gyun Kim, Jae Sik Lee and Kang Young Lee
$\alpha_s(M_Z^2)$ and $R_b$ discrepancy with nonuniversal interactions
9 pages, ReVTeX, 1 table and 1 figure
Phys.Rev. D53 (1996) 1712-1714
10.1103/PhysRevD.53.1712
KAIST-CHEP-95/14
hep-ph
null
We implement global fits to LEP data with the \non interactions. Consistent $R_b$ with experimental value and consistent $\as(M_Z^2)$ with that from low energy experiments are obtained. We also find that the $\xx$ is better than the Standard Model. And we argue that other kinds of new physics are needed to explain the difference between the values of $\as(M_Z^2)$ from low energy experiments and from the 3-jet ratio.
[ { "created": "Mon, 18 Sep 1995 13:58:32 GMT", "version": "v1" } ]
2009-10-28
[ [ "Kim", "Jae Kwan", "" ], [ "Kim", "Yeong Gyun", "" ], [ "Lee", "Jae Sik", "" ], [ "Lee", "Kang Young", "" ] ]
We implement global fits to LEP data with the \non interactions. Consistent $R_b$ with experimental value and consistent $\as(M_Z^2)$ with that from low energy experiments are obtained. We also find that the $\xx$ is better than the Standard Model. And we argue that other kinds of new physics are needed to explain the difference between the values of $\as(M_Z^2)$ from low energy experiments and from the 3-jet ratio.
2303.11149
Bhag C. Chauhan
Ankush, Rishu Verma, Sahil Kumar and B. C. Chauhan
Leptogenesis and Neutrinoless Double Beta Decay in the Scotogenic Hybrid Textures of Neutrino Mass Matrix
19 pages, 6 figures, 4 tables, section 2, 3 and 5 restructured
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In our recent work we identify the hybrid textures of neutrino mass matrix which simultaneously account for dark matter (DM) and neutrinoless double beta decay ($0\nu\beta\beta$). We also obtained the bounds on dark matter mass and effective Majorana mass $|M_{ee}|$. In this work we look for those hybrid textures which altogether accounts for DM, $0\nu\beta\beta$ and leptogenesis. We have found correlation of baryon asymmetry of universe $Y$ with dark matter mass $M_1$ and effective Majorana mass $|M_{ee}|$. We use experimental bounds on relic density of dark matter ($\Omega h^2$) and baryon asymmetry of universe to identify the hybrid textures. We found that out of five hybrid textures which simultaneously satisfies the physics observations of the DM and $0\nu\beta\beta$ only three hybrid textures altogether satisfy the DM, $0\nu\beta\beta$ and leptogenesis. It is interesting to note that these three hybrid textures gives lower bound to the effective Majorana mass $|M_{ee}|$ which can be probed in current and future experiments like SuperNEMO, KamLAND-Zen, NEXT, and nEXO (5 year) have sensitivity reaches of 0.05 eV, 0.045 eV, 0.03 eV, and 0.015 eV, respectively.
[ { "created": "Mon, 20 Mar 2023 14:32:42 GMT", "version": "v1" }, { "created": "Tue, 21 Mar 2023 16:00:26 GMT", "version": "v2" } ]
2023-03-22
[ [ "Ankush", "", "" ], [ "Verma", "Rishu", "" ], [ "Kumar", "Sahil", "" ], [ "Chauhan", "B. C.", "" ] ]
In our recent work we identify the hybrid textures of neutrino mass matrix which simultaneously account for dark matter (DM) and neutrinoless double beta decay ($0\nu\beta\beta$). We also obtained the bounds on dark matter mass and effective Majorana mass $|M_{ee}|$. In this work we look for those hybrid textures which altogether accounts for DM, $0\nu\beta\beta$ and leptogenesis. We have found correlation of baryon asymmetry of universe $Y$ with dark matter mass $M_1$ and effective Majorana mass $|M_{ee}|$. We use experimental bounds on relic density of dark matter ($\Omega h^2$) and baryon asymmetry of universe to identify the hybrid textures. We found that out of five hybrid textures which simultaneously satisfies the physics observations of the DM and $0\nu\beta\beta$ only three hybrid textures altogether satisfy the DM, $0\nu\beta\beta$ and leptogenesis. It is interesting to note that these three hybrid textures gives lower bound to the effective Majorana mass $|M_{ee}|$ which can be probed in current and future experiments like SuperNEMO, KamLAND-Zen, NEXT, and nEXO (5 year) have sensitivity reaches of 0.05 eV, 0.045 eV, 0.03 eV, and 0.015 eV, respectively.
hep-ph/0112149
L. T. Handoko
L. T. Handoko, C. S. Kim, T. Yoshikawa
Longitudinal polarization asymmetry of leptons in the pure leptonic B decays
7 pages
Phys.Rev. D65 (2002) 077506
10.1103/PhysRevD.65.077506
FISIKALIPI-01005, FIS-UI-TH-01-01, IFP-803-UNC
hep-ph
null
Longitudinal lepton polarization asymmetry in B_q -> l l (q = d, s$ and l = e, mu, tau) decays is investigated. The analysis is done in a general manner by using the effective operators approach. It is shown that the longitudinal lepton polarization asymmetry would provide a direct search for the scalar and pseudoscalar type interactions, which are induced in all variants of Higgs-doublet models.
[ { "created": "Tue, 11 Dec 2001 07:35:24 GMT", "version": "v1" }, { "created": "Thu, 11 Apr 2002 16:01:21 GMT", "version": "v2" } ]
2009-11-07
[ [ "Handoko", "L. T.", "" ], [ "Kim", "C. S.", "" ], [ "Yoshikawa", "T.", "" ] ]
Longitudinal lepton polarization asymmetry in B_q -> l l (q = d, s$ and l = e, mu, tau) decays is investigated. The analysis is done in a general manner by using the effective operators approach. It is shown that the longitudinal lepton polarization asymmetry would provide a direct search for the scalar and pseudoscalar type interactions, which are induced in all variants of Higgs-doublet models.
hep-ph/0303153
Juan Garcia-Bellido
Juan Garcia-Bellido
The evolution of the Universe
15 pages, 6 figures, LaTeX, uses ws-procs975x65.cls (included). Invited Plenary Talk at the international colloquium on TIME AND MATTER, Venice, Italy, August 11 - 17, 2002
null
null
CERN-TH/2002-204, IFT-UAM/CSIC-03-11
hep-ph
null
With the recent measurements of temperature and polarization anisotropies in the microwave background by WMAP, we have entered a new era of precision cosmology, with the cosmological parameters of a Standard Cosmological Model determined to 1%. This Standard Model is based on the Big Bang theory and the inflationary paradigm, a period of exponential expansion in the early universe responsible for the large-scale homogeneity and spatial flatness of our observable patch of the Universe. The spectrum of metric perturbations, seen in the microwave background as temperature anisotropies, were produced during inflation from quantum fluctuations that were stretched to cosmological size by the expansion, and later gave rise, via gravitational collapse, to the observed large-scale structure of clusters and superclusters of galaxies. Furthermore, the same theory predicts that all the matter and radiation in the universe today originated at the end of inflation from an explosive production of particles that could also have been the origin of the present baryon asymmetry, before the universe reached thermal equilibrium at a very large temperature. From there on, the universe cooled down as it expanded, in the way described by the standard hot Big Bang model.
[ { "created": "Tue, 18 Mar 2003 18:12:02 GMT", "version": "v1" } ]
2007-05-23
[ [ "Garcia-Bellido", "Juan", "" ] ]
With the recent measurements of temperature and polarization anisotropies in the microwave background by WMAP, we have entered a new era of precision cosmology, with the cosmological parameters of a Standard Cosmological Model determined to 1%. This Standard Model is based on the Big Bang theory and the inflationary paradigm, a period of exponential expansion in the early universe responsible for the large-scale homogeneity and spatial flatness of our observable patch of the Universe. The spectrum of metric perturbations, seen in the microwave background as temperature anisotropies, were produced during inflation from quantum fluctuations that were stretched to cosmological size by the expansion, and later gave rise, via gravitational collapse, to the observed large-scale structure of clusters and superclusters of galaxies. Furthermore, the same theory predicts that all the matter and radiation in the universe today originated at the end of inflation from an explosive production of particles that could also have been the origin of the present baryon asymmetry, before the universe reached thermal equilibrium at a very large temperature. From there on, the universe cooled down as it expanded, in the way described by the standard hot Big Bang model.
1509.01466
Nobuchika Okada
Arindam Das, Nobuchika Okada, Nathan Papapietro
Electroweak vacuum stability in classically conformal B-L extension of the Standard Model
28 pages, 4 figures, version to be published in European Physical Journal C
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the minimal U(1)$_{B-L}$ extension of the Standard Model (SM) with the classically conformal invariance, where an anomaly free U(1)$_{B-L}$ gauge symmetry is introduced along with three generations of right-handed neutrinos and a U(1)$_{B-L}$ Higgs field. Because of the classically conformal symmetry, all dimensional parameters are forbidden. The $B-L$ gauge symmetry is radiatively broken through the Coleman-Weinberg mechanism, generating the mass for the $U(1)_{B-L}$ gauge boson ($Z^\prime$ boson) and the right-handed neutrinos. Through a small negative coupling between the SM Higgs doublet and the $B-L$ Higgs field, the negative mass term for the SM Higgs doublet is generated and the electroweak symmetry is broken. In this model context, we investigate the electroweak vacuum instability problem in the SM. It is known that in the classically conformal U(1)$_{B-L}$ extension of the SM, the electroweak vacuum remains unstable in the renormalization group analysis at the one-loop level. In this paper, we extend the analysis to the two-loop level, and perform parameter scans. We identify a parameter region which not only solve the vacuum instability problem, but also satisfy the recent ATLAS and CMS bounds from search for $Z^\prime$ boson resonance at the LHC Run-2. Considering self-energy corrections to the SM Higgs doublet through the right-handed neutrinos and the $Z^\prime$ boson, we derive the naturalness bound on the model parameters to realize the electroweak scale without fine-tunings.
[ { "created": "Fri, 4 Sep 2015 14:33:23 GMT", "version": "v1" }, { "created": "Wed, 9 Sep 2015 19:15:28 GMT", "version": "v2" }, { "created": "Sat, 6 Feb 2016 22:38:35 GMT", "version": "v3" }, { "created": "Sun, 12 Feb 2017 06:26:03 GMT", "version": "v4" } ]
2017-02-14
[ [ "Das", "Arindam", "" ], [ "Okada", "Nobuchika", "" ], [ "Papapietro", "Nathan", "" ] ]
We consider the minimal U(1)$_{B-L}$ extension of the Standard Model (SM) with the classically conformal invariance, where an anomaly free U(1)$_{B-L}$ gauge symmetry is introduced along with three generations of right-handed neutrinos and a U(1)$_{B-L}$ Higgs field. Because of the classically conformal symmetry, all dimensional parameters are forbidden. The $B-L$ gauge symmetry is radiatively broken through the Coleman-Weinberg mechanism, generating the mass for the $U(1)_{B-L}$ gauge boson ($Z^\prime$ boson) and the right-handed neutrinos. Through a small negative coupling between the SM Higgs doublet and the $B-L$ Higgs field, the negative mass term for the SM Higgs doublet is generated and the electroweak symmetry is broken. In this model context, we investigate the electroweak vacuum instability problem in the SM. It is known that in the classically conformal U(1)$_{B-L}$ extension of the SM, the electroweak vacuum remains unstable in the renormalization group analysis at the one-loop level. In this paper, we extend the analysis to the two-loop level, and perform parameter scans. We identify a parameter region which not only solve the vacuum instability problem, but also satisfy the recent ATLAS and CMS bounds from search for $Z^\prime$ boson resonance at the LHC Run-2. Considering self-energy corrections to the SM Higgs doublet through the right-handed neutrinos and the $Z^\prime$ boson, we derive the naturalness bound on the model parameters to realize the electroweak scale without fine-tunings.
hep-ph/0702198
Stefano Frixione
S. Frixione, E. Laenen, P. Motylinski, B.R. Webber
Angular correlations of lepton pairs from vector boson and top quark decays in Monte Carlo simulations
20 pages Latex; 6 figures included
JHEP 0704:081,2007
10.1088/1126-6708/2007/04/081
Cavendish-HEP-07/01, GEF-TH-09/2007, ITP-UU-07/10, NIKHEF/2007-004
hep-ph
null
We explain how angular correlations in leptonic decays of vector bosons and top quarks can be included in Monte Carlo parton showers, in particular those matched to NLO QCD computations. We consider the production of $n$ pairs of leptons, originating from the decays of $n$ electroweak vector bosons or of $n$ top quarks, in the narrow-width approximation. In the latter case, the information on the $n$ $b$ quarks emerging from the decays is also retained. We give results of implementing this procedure in MC@NLO
[ { "created": "Tue, 20 Feb 2007 08:50:29 GMT", "version": "v1" } ]
2010-10-27
[ [ "Frixione", "S.", "" ], [ "Laenen", "E.", "" ], [ "Motylinski", "P.", "" ], [ "Webber", "B. R.", "" ] ]
We explain how angular correlations in leptonic decays of vector bosons and top quarks can be included in Monte Carlo parton showers, in particular those matched to NLO QCD computations. We consider the production of $n$ pairs of leptons, originating from the decays of $n$ electroweak vector bosons or of $n$ top quarks, in the narrow-width approximation. In the latter case, the information on the $n$ $b$ quarks emerging from the decays is also retained. We give results of implementing this procedure in MC@NLO
hep-ph/9211335
Michael Martin Nieto
V. Alan Kosteleck\'y, Michael Martin Nieto, and D. Rodney Truax
Supersqueezed States
21 pages, LaTeX
Phys.Rev.A48:1045-1054,1993
10.1103/PhysRevA.48.1045
Indiana Uniersity preprint IUHET-224; Los Alamos preprint LAUR-92-2708
hep-ph
null
We derive the supersqueeze operator for the supersymmetric harmonic oscillator, using Baker-Campbell-Hausdorff relations for the supergroup OSP(2/2). Combining this with the previously obtained superdisplacement operator, we derive the supersqueezed states. These are the supersymmetric generalization of the squeezed states of the harmonic oscillator.
[ { "created": "Mon, 30 Nov 1992 21:03:43 GMT", "version": "v1" } ]
2016-08-14
[ [ "Kostelecký", "V. Alan", "" ], [ "Nieto", "Michael Martin", "" ], [ "Truax", "D. Rodney", "" ] ]
We derive the supersqueeze operator for the supersymmetric harmonic oscillator, using Baker-Campbell-Hausdorff relations for the supergroup OSP(2/2). Combining this with the previously obtained superdisplacement operator, we derive the supersqueezed states. These are the supersymmetric generalization of the squeezed states of the harmonic oscillator.
1206.1284
Konstantin Chetyrkin G.
P. A. Baikov, K. G. Chetyrkin, J. H. K\"uhn and J. Rittinger
Vector Correlator in Massless QCD at Order O(alpha_s^4) and the QED beta-function at five loop
14 pages, 1 figure; Few misprints corrected. Results are untouched
JHEP 1207 (2012) 017
10.1007/JHEP07(2012)017
SFB/CPP-12-36; TTP12-018
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a concise summary of recent results for the vector correlator in massless QCD at order ${\cal O}(\alpha_s^4)$, with all colour factors being given for a generic colour group. As a direct consequence we arrive at: (i) the full QCD contribution to the QED $\beta$--function of order $\alpha^2\, \alpha_s^4$ in the MSbar- and MOM-schemes; (ii) the full five-loop result of order $\alpha^6$ for the $\beta$-function of QED with a generic number of single-charged fermions, again for the MSbar- and MOM-schemes.
[ { "created": "Wed, 6 Jun 2012 17:40:51 GMT", "version": "v1" }, { "created": "Wed, 10 Oct 2012 10:48:05 GMT", "version": "v2" } ]
2015-06-05
[ [ "Baikov", "P. A.", "" ], [ "Chetyrkin", "K. G.", "" ], [ "Kühn", "J. H.", "" ], [ "Rittinger", "J.", "" ] ]
We present a concise summary of recent results for the vector correlator in massless QCD at order ${\cal O}(\alpha_s^4)$, with all colour factors being given for a generic colour group. As a direct consequence we arrive at: (i) the full QCD contribution to the QED $\beta$--function of order $\alpha^2\, \alpha_s^4$ in the MSbar- and MOM-schemes; (ii) the full five-loop result of order $\alpha^6$ for the $\beta$-function of QED with a generic number of single-charged fermions, again for the MSbar- and MOM-schemes.
2111.06883
Rene Oswald
R. Oswald, A. Nevsky, V. Vogt, S. Schiller, N. L. Figueroa, K. Zhang, O. Tretiak, D. Antypas, D. Budker, A. Banerjee, G. Perez
Search for oscillations of fundamental constants using molecular spectroscopy
23 pages,9 figures
null
10.1103/PhysRevLett.129.031302
null
hep-ph physics.atom-ph
http://creativecommons.org/licenses/by/4.0/
A possible implication of an ultralight dark matter (UDM) field interacting wibeginth the Standard Model (SM) degrees of freedom is oscillations of fundamental constants. Here, we establish direct experimental bounds on the coupling of an oscillating UDM field to the up, down, and strange quarks and to the gluons, for oscillation frequencies between 10 Hz and 10^8 Hz. We employ spectroscopic experiments that take advantage of the dependence of molecular transition frequencies on the nuclear masses. Our results apply to previously unexplored frequency bands, and improve on existing bounds at frequencies > 5 MHz. We identify a sector of UDM - SM coupling space where the bounds from Equivalence Principle tests may be challenged by next-generation experiments of the present kind.
[ { "created": "Fri, 12 Nov 2021 18:58:20 GMT", "version": "v1" } ]
2022-07-27
[ [ "Oswald", "R.", "" ], [ "Nevsky", "A.", "" ], [ "Vogt", "V.", "" ], [ "Schiller", "S.", "" ], [ "Figueroa", "N. L.", "" ], [ "Zhang", "K.", "" ], [ "Tretiak", "O.", "" ], [ "Antypas", "D.", "" ], [ "Budker", "D.", "" ], [ "Banerjee", "A.", "" ], [ "Perez", "G.", "" ] ]
A possible implication of an ultralight dark matter (UDM) field interacting wibeginth the Standard Model (SM) degrees of freedom is oscillations of fundamental constants. Here, we establish direct experimental bounds on the coupling of an oscillating UDM field to the up, down, and strange quarks and to the gluons, for oscillation frequencies between 10 Hz and 10^8 Hz. We employ spectroscopic experiments that take advantage of the dependence of molecular transition frequencies on the nuclear masses. Our results apply to previously unexplored frequency bands, and improve on existing bounds at frequencies > 5 MHz. We identify a sector of UDM - SM coupling space where the bounds from Equivalence Principle tests may be challenged by next-generation experiments of the present kind.
hep-ph/9401213
Don Lichtenberg
R. Roncaglia, A. R. Dzierba, D. B. Lichtenberg, and E. Predazzi
A New Method to Predict Meson Masses
7 pages in plaintex, two figures not included available from authors (lichten@indiana.edu), IUHET 270
null
null
null
hep-ph
null
The Feynman--Hellmann theorem is used to show that vector meson energy eigenvalues are monotonically decreasing functions of the reduced masses of their constituent quarks. The experimental meson masses are used to put constraints on the values of quark masses and to predict the masses of some as yet undiscovered mesons. The mass of the $B_c^*$ meson is predicted to be $6320\pm 10$ MeV, and, with less precision, the masses of a number of excited vector mesons are also predicted.
[ { "created": "Thu, 6 Jan 1994 13:50:50 GMT", "version": "v1" } ]
2009-09-25
[ [ "Roncaglia", "R.", "" ], [ "Dzierba", "A. R.", "" ], [ "Lichtenberg", "D. B.", "" ], [ "Predazzi", "E.", "" ] ]
The Feynman--Hellmann theorem is used to show that vector meson energy eigenvalues are monotonically decreasing functions of the reduced masses of their constituent quarks. The experimental meson masses are used to put constraints on the values of quark masses and to predict the masses of some as yet undiscovered mesons. The mass of the $B_c^*$ meson is predicted to be $6320\pm 10$ MeV, and, with less precision, the masses of a number of excited vector mesons are also predicted.
hep-ph/9506273
Aneesh Manohar
Jin Dai, Roger Dashen, Elizabeth Jenkins, and Aneesh V. Manohar
Flavor Symmetry Breaking in the 1/N Expansion
13 pages, 4 epsf figures, uses revtex
Phys.Rev.D53:273-282,1996
10.1103/PhysRevD.53.273
UCSD/PTH 94-19
hep-ph
null
The breaking of flavor SU(3) symmetry in the axial couplings and magnetic moments of baryons is analyzed in the $1/N_c$ expansion. A simple meson loop graph which is known to be of order $\sqrt{m_s}$ and leading order in $1/N_c$ correctly predicts the pattern of symmetry breaking in the magnetic moments. It is, however, not possible to use this graph to predict the magnitude of the breaking. The situation with the axial couplings is less clear. In this case the breakings are relatively small and do not appear to follow an obvious pattern. Nevertheless there is a clear indication that, with symmetry breaking taken into account, the F/D ratio (defined in the presence of SU(3) breaking) is considerably less than the SU(6) value of 2/3. With sizeable uncertainty, we find F/D \approx 0.44. The quantity 3F-D which is relevant for the analysis of spin-dependent deep inelastic scattering is considerably smaller than the SU(6) value of unity. The new value, 3F-D=0.27+-0.09, is consistent with vanishing strange-quark spin in the nucleon.
[ { "created": "Thu, 8 Jun 1995 21:50:52 GMT", "version": "v1" } ]
2010-04-06
[ [ "Dai", "Jin", "" ], [ "Dashen", "Roger", "" ], [ "Jenkins", "Elizabeth", "" ], [ "Manohar", "Aneesh V.", "" ] ]
The breaking of flavor SU(3) symmetry in the axial couplings and magnetic moments of baryons is analyzed in the $1/N_c$ expansion. A simple meson loop graph which is known to be of order $\sqrt{m_s}$ and leading order in $1/N_c$ correctly predicts the pattern of symmetry breaking in the magnetic moments. It is, however, not possible to use this graph to predict the magnitude of the breaking. The situation with the axial couplings is less clear. In this case the breakings are relatively small and do not appear to follow an obvious pattern. Nevertheless there is a clear indication that, with symmetry breaking taken into account, the F/D ratio (defined in the presence of SU(3) breaking) is considerably less than the SU(6) value of 2/3. With sizeable uncertainty, we find F/D \approx 0.44. The quantity 3F-D which is relevant for the analysis of spin-dependent deep inelastic scattering is considerably smaller than the SU(6) value of unity. The new value, 3F-D=0.27+-0.09, is consistent with vanishing strange-quark spin in the nucleon.
0705.1195
Li Tong
Tong Li, Shu-Min Zhao and Xue-Qian Li
Comprehensive Calculations on the OZI-forbidden Nonleptonic Decays of Orthoquarkonia $J/\psi(\Upsilon)\to \pi\pi,\rho\pi$
25 pages, 1 figure and 4 tables. Numerical results slightly changed
Nucl.Phys.A828:125-135,2009
10.1016/j.nuclphysa.2009.06.021
null
hep-ph
null
In this work, we calculate the decay rates of the OZI-forbidden processes $J/\psi(\Upsilon)\to \pi\pi, \rho\pi$ at the order of the leading-twist distribution amplitude. The process of $J/\psi(\Upsilon)\to \pi^+ \pi^-$ violates isospin conservation and the amplitude is explicitly proportional to the isospin violation factor $m_u-m_d$, our numerical results on their decay rates are consistent with the data. The process $J/\psi(\Upsilon)\to \rho\pi$ violates the hadronic helicity conservation and should be suppressed, as indicated in literature, its decay rate can only be proportional to $m_q^2$ at the order of leading twist. Our theoretical evaluation confirms this statement that the theoretical evaluation on $\Gamma(J/\psi(\Upsilon)\to \rho\pi)$ is almost one order smaller than the data unless the model parameters take certain extreme values. It may imply that the sizable branching ratio of $J/\psi(\Upsilon)\to \rho\pi$ should be explained by either higher twist contributions or other mechanisms.
[ { "created": "Wed, 9 May 2007 00:56:16 GMT", "version": "v1" }, { "created": "Sun, 17 Jun 2007 12:32:59 GMT", "version": "v2" }, { "created": "Mon, 18 Jun 2007 23:17:47 GMT", "version": "v3" } ]
2009-08-17
[ [ "Li", "Tong", "" ], [ "Zhao", "Shu-Min", "" ], [ "Li", "Xue-Qian", "" ] ]
In this work, we calculate the decay rates of the OZI-forbidden processes $J/\psi(\Upsilon)\to \pi\pi, \rho\pi$ at the order of the leading-twist distribution amplitude. The process of $J/\psi(\Upsilon)\to \pi^+ \pi^-$ violates isospin conservation and the amplitude is explicitly proportional to the isospin violation factor $m_u-m_d$, our numerical results on their decay rates are consistent with the data. The process $J/\psi(\Upsilon)\to \rho\pi$ violates the hadronic helicity conservation and should be suppressed, as indicated in literature, its decay rate can only be proportional to $m_q^2$ at the order of leading twist. Our theoretical evaluation confirms this statement that the theoretical evaluation on $\Gamma(J/\psi(\Upsilon)\to \rho\pi)$ is almost one order smaller than the data unless the model parameters take certain extreme values. It may imply that the sizable branching ratio of $J/\psi(\Upsilon)\to \rho\pi$ should be explained by either higher twist contributions or other mechanisms.
2012.03693
George Rupp
Eef van Beveren and George Rupp
Modern meson spectroscopy: the fundamental role of unitarity
Invited review paper, 51 pages, 16 figures, 4 tables; to be published in "Progress in Particle and Nuclear Physics" 2021. v2: several typos corrected, in particular in Eqs. (15), (17), (36), and (37) in Section 2; some accompanying remarks rephrased for clarity; Eq. (41) improved. NOTE: v3 is identical to v2; published version (in print and online) largely corresponds to v1; v3 (=v2) is correct
Progress in Particle and Nuclear Physics 117 (2021) 103845
10.1016/j.ppnp.2020.103845
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The importance of $S$-matrix unitarity in realistic meson spectroscopy is reviewed, both its historical development and more recent applications. First the effects of imposing $S$-matrix unitarity on meson resonances is demonstrated in both the elastic and the inelastic case. Then, the static quark model is revisited and its theoretical as well as phenomenological shortcomings are highlighted. A detailed account is presented of the mesons in the tables of the Particle Data Group that cannot be explained at all or only poorly in models describing mesons as pure quark-antiquark bound states. Next the earliest unitarised and coupled-channel models are revisited, followed by several examples of puzzling meson resonances and their understanding in a modern unitarised framework. Also, recent and fully unquenched lattice descriptions of such mesons are summarised. Finally, attention is paid to production processes, which require an unconventional yet related unitary approach. Proposals for further improvement are discussed.
[ { "created": "Mon, 7 Dec 2020 13:49:07 GMT", "version": "v1" }, { "created": "Mon, 28 Dec 2020 14:50:41 GMT", "version": "v2" }, { "created": "Wed, 9 Jun 2021 13:44:08 GMT", "version": "v3" } ]
2021-06-10
[ [ "van Beveren", "Eef", "" ], [ "Rupp", "George", "" ] ]
The importance of $S$-matrix unitarity in realistic meson spectroscopy is reviewed, both its historical development and more recent applications. First the effects of imposing $S$-matrix unitarity on meson resonances is demonstrated in both the elastic and the inelastic case. Then, the static quark model is revisited and its theoretical as well as phenomenological shortcomings are highlighted. A detailed account is presented of the mesons in the tables of the Particle Data Group that cannot be explained at all or only poorly in models describing mesons as pure quark-antiquark bound states. Next the earliest unitarised and coupled-channel models are revisited, followed by several examples of puzzling meson resonances and their understanding in a modern unitarised framework. Also, recent and fully unquenched lattice descriptions of such mesons are summarised. Finally, attention is paid to production processes, which require an unconventional yet related unitary approach. Proposals for further improvement are discussed.
1802.06597
Peter Kroll
P. Kroll and K. Passek-Kumericki
Twist-3 contributions to wide-angle photoproduction of pions
36 pages, 6 figures using latex, minor changes, accepted for publication
Phys. Rev. D 97, 074023 (2018)
10.1103/PhysRevD.97.074023
WU-B 18-00
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate wide-angle pi^0 photoproduction within the handbag approach to twist-3 accuracy. In contrast to earlier work both the 2-particle as well as the 3-particle twist-3 contributions are taken into account. It is shown that both are needed for consistent results that respect gauge invariance and crossing properties. The numerical studies reveal the dominance of the twist-3 contribution. With it fair agreement with the recent CLAS measurement of the pi^0 cross section is obtained. We briefly comment also on wide-angle photoproduction of other pseudoscalar mesons.
[ { "created": "Mon, 19 Feb 2018 12:03:30 GMT", "version": "v1" }, { "created": "Fri, 13 Apr 2018 09:41:43 GMT", "version": "v2" } ]
2018-05-02
[ [ "Kroll", "P.", "" ], [ "Passek-Kumericki", "K.", "" ] ]
We investigate wide-angle pi^0 photoproduction within the handbag approach to twist-3 accuracy. In contrast to earlier work both the 2-particle as well as the 3-particle twist-3 contributions are taken into account. It is shown that both are needed for consistent results that respect gauge invariance and crossing properties. The numerical studies reveal the dominance of the twist-3 contribution. With it fair agreement with the recent CLAS measurement of the pi^0 cross section is obtained. We briefly comment also on wide-angle photoproduction of other pseudoscalar mesons.
2011.08205
Matthias K\"onig
Mathias Heiles, Matthias K\"onig, Matthias Neubert
Effective Field Theory for Heavy Vector Resonances Coupled to the Standard Model
33 pages, 6 figures, 2 appendices
null
10.1007/JHEP02(2021)204
MITP/20-053, TUM-HEP-1290/20, ZH-TH-39/20
hep-ph
http://creativecommons.org/licenses/by/4.0/
We construct an effective field theory describing the decays of a heavy vector resonance $V$ into Standard Model particles. The effective theory is built using an extension of Soft-Collinear Effective Theory called SCET$_{\rm BSM}$, which provides a rigorous framework for parameterizing decay matrix elements with manifest power counting in the ratio of the electroweak scale and the mass of the resonance, $\lambda\sim v/m_V$. Using the renormalization-group evolution of the couplings in the effective Lagrangian, large logarithms associated with this scale ratio can be resummed to all orders. We consider in detail the two-body decays of a heavy $Z'$ boson and of a Kaluza-Klein gluon at leading and subleading order in $\lambda$. We illustrate the matching onto SCET$_{\rm BSM}$ with a concrete example of a UV-complete new-physics model.
[ { "created": "Mon, 16 Nov 2020 19:00:15 GMT", "version": "v1" } ]
2021-03-17
[ [ "Heiles", "Mathias", "" ], [ "König", "Matthias", "" ], [ "Neubert", "Matthias", "" ] ]
We construct an effective field theory describing the decays of a heavy vector resonance $V$ into Standard Model particles. The effective theory is built using an extension of Soft-Collinear Effective Theory called SCET$_{\rm BSM}$, which provides a rigorous framework for parameterizing decay matrix elements with manifest power counting in the ratio of the electroweak scale and the mass of the resonance, $\lambda\sim v/m_V$. Using the renormalization-group evolution of the couplings in the effective Lagrangian, large logarithms associated with this scale ratio can be resummed to all orders. We consider in detail the two-body decays of a heavy $Z'$ boson and of a Kaluza-Klein gluon at leading and subleading order in $\lambda$. We illustrate the matching onto SCET$_{\rm BSM}$ with a concrete example of a UV-complete new-physics model.
0705.3589
Pavel Fileviez Perez
Pavel Fileviez Perez
Supersymmetric Adjoint SU(5)
5 pages, section III expanded, reference added, conclusions unchanged
Phys.Rev.D76:071701,2007
10.1103/PhysRevD.76.071701
null
hep-ph hep-th
null
Recently we have proposed a renormalizable grand unified theory, based on the SU(5) gauge symmetry, where the neutrino masses are generated through the type I and type III seesaw mechanisms. In this letter we study the supersymmetric version of this theory. As in the non-susy version it is possible to generate all fermion masses with the minimal number of Higgses, the theory predicts one massless neutrino and the leptogenesis mechanism can be realized. All contributions to the decay of the proton and the properties of neutralinos are discussed. This theory can be considered as the simplest renormalizable supersymmetric grand unified theory based on the SU(5) gauge symmetry since it has the minimal number of superfields and free parameters.
[ { "created": "Thu, 24 May 2007 14:07:03 GMT", "version": "v1" }, { "created": "Tue, 10 Jul 2007 16:06:11 GMT", "version": "v2" } ]
2011-11-09
[ [ "Perez", "Pavel Fileviez", "" ] ]
Recently we have proposed a renormalizable grand unified theory, based on the SU(5) gauge symmetry, where the neutrino masses are generated through the type I and type III seesaw mechanisms. In this letter we study the supersymmetric version of this theory. As in the non-susy version it is possible to generate all fermion masses with the minimal number of Higgses, the theory predicts one massless neutrino and the leptogenesis mechanism can be realized. All contributions to the decay of the proton and the properties of neutralinos are discussed. This theory can be considered as the simplest renormalizable supersymmetric grand unified theory based on the SU(5) gauge symmetry since it has the minimal number of superfields and free parameters.
hep-ph/0510186
Micha Berkooz
Micha Berkooz (Weizmann), Daniel J.H. Chung (Wisconsin), Tomer Volansky (Weizmann)
High Density Preheating Effects on Q-ball Decays and MSSM Inflation
4 pages
Phys.Rev.Lett. 96 (2006) 031303
10.1103/PhysRevLett.96.031303
null
hep-ph astro-ph
null
Non-perturbative preheating decay of post-inflationary condensates often results in a high density, low momenta, non-thermal gas. In the case where the non-perturbative classical evolution also leads to Q-balls, this effect shields them from instant dissociation, and may radically change the thermal history of the universe. For example, in a large class of inflationary scenarios, motivated by the MSSM and its embedding in string theory, the reheat temperature changes by a multiplicative factor of $10^{12}$.
[ { "created": "Fri, 14 Oct 2005 07:29:14 GMT", "version": "v1" } ]
2009-11-11
[ [ "Berkooz", "Micha", "", "Weizmann" ], [ "Chung", "Daniel J. H.", "", "Wisconsin" ], [ "Volansky", "Tomer", "", "Weizmann" ] ]
Non-perturbative preheating decay of post-inflationary condensates often results in a high density, low momenta, non-thermal gas. In the case where the non-perturbative classical evolution also leads to Q-balls, this effect shields them from instant dissociation, and may radically change the thermal history of the universe. For example, in a large class of inflationary scenarios, motivated by the MSSM and its embedding in string theory, the reheat temperature changes by a multiplicative factor of $10^{12}$.
1805.07381
Vijay Narayan
Peter Graham and Ryan Janish and Vijay Narayan and Surjeet Rajendran and Paul Riggins
White Dwarfs as Dark Matter Detectors
references added and minor typos fixed. match to published version in PRD
Phys. Rev. D 98, 115027 (2018)
10.1103/PhysRevD.98.115027
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dark matter that is capable of sufficiently heating a local region in a white dwarf will trigger runaway fusion and ignite a type Ia supernova. This was originally proposed in Graham et al. (2015) and used to constrain primordial black holes which transit and heat a white dwarf via dynamical friction. In this paper, we consider dark matter (DM) candidates that heat through the production of high-energy standard model (SM) particles, and show that such particles will efficiently thermalize the white dwarf medium and ignite supernovae. Based on the existence of long-lived white dwarfs and the observed supernovae rate, we derive new constraints on ultra-heavy DM which produce SM particles through DM-DM annihilations, DM decays, and DM-SM scattering interactions in the stellar medium. As a concrete example, we rule out supersymmetric Q-ball DM in parameter space complementary to terrestrial bounds. We put further constraints on DM that is captured by white dwarfs, considering the formation and self-gravitational collapse of a DM core which heats the star via decays and annihilations within the core. It is also intriguing that the DM-induced ignition discussed in this work provide an alternative mechanism of triggering supernovae from sub-Chandrasekhar, non-binary progenitors.
[ { "created": "Fri, 18 May 2018 18:30:42 GMT", "version": "v1" }, { "created": "Wed, 5 Dec 2018 18:40:01 GMT", "version": "v2" } ]
2019-01-02
[ [ "Graham", "Peter", "" ], [ "Janish", "Ryan", "" ], [ "Narayan", "Vijay", "" ], [ "Rajendran", "Surjeet", "" ], [ "Riggins", "Paul", "" ] ]
Dark matter that is capable of sufficiently heating a local region in a white dwarf will trigger runaway fusion and ignite a type Ia supernova. This was originally proposed in Graham et al. (2015) and used to constrain primordial black holes which transit and heat a white dwarf via dynamical friction. In this paper, we consider dark matter (DM) candidates that heat through the production of high-energy standard model (SM) particles, and show that such particles will efficiently thermalize the white dwarf medium and ignite supernovae. Based on the existence of long-lived white dwarfs and the observed supernovae rate, we derive new constraints on ultra-heavy DM which produce SM particles through DM-DM annihilations, DM decays, and DM-SM scattering interactions in the stellar medium. As a concrete example, we rule out supersymmetric Q-ball DM in parameter space complementary to terrestrial bounds. We put further constraints on DM that is captured by white dwarfs, considering the formation and self-gravitational collapse of a DM core which heats the star via decays and annihilations within the core. It is also intriguing that the DM-induced ignition discussed in this work provide an alternative mechanism of triggering supernovae from sub-Chandrasekhar, non-binary progenitors.
hep-ph/9510226
J. Gunion
J.F. Gunion (U.C. Davis)
Physics at a $\mu^+\mu^-$ Collider
4 pages, full uuencoded postscript file with inserted figures has been submitted, to appear in the Proceedings of the 1995 Brussells EPS meeting, full postscript file including figures also available via anonymous ftp at ftp://ucdhep.ucdavis.edu/gunion/ , get mupmum_eps.ps
null
null
UCD-95-35
hep-ph
null
A brief overview of the physics capabilities of a $\mu^+\mu^-$ collider is given, with particular focus on special Higgs sector opportunities.
[ { "created": "Thu, 5 Oct 1995 02:53:05 GMT", "version": "v1" } ]
2007-05-23
[ [ "Gunion", "J. F.", "", "U.C. Davis" ] ]
A brief overview of the physics capabilities of a $\mu^+\mu^-$ collider is given, with particular focus on special Higgs sector opportunities.
1007.0706
Shinya Kanemura
Mayumi Aoki and Shinya Kanemura
Probing the Majorana nature of TeV-scale radiative seesaw models at the ILC
8pages, 6 figures, Proceedings of LCWS/ILC2010
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Two important features of TeV-scale radiative seesaw models, in which tiny neutrino masses are generated at the quantum level, are an extended scalar (Higgs) sector and the Majorana nature. We study phenomenological aspects of these models at the ILC. It is found that the Majorana nature of the models can be tested directly via the electron-positron and electron-electron collision experiments.
[ { "created": "Mon, 5 Jul 2010 15:46:50 GMT", "version": "v1" } ]
2010-07-06
[ [ "Aoki", "Mayumi", "" ], [ "Kanemura", "Shinya", "" ] ]
Two important features of TeV-scale radiative seesaw models, in which tiny neutrino masses are generated at the quantum level, are an extended scalar (Higgs) sector and the Majorana nature. We study phenomenological aspects of these models at the ILC. It is found that the Majorana nature of the models can be tested directly via the electron-positron and electron-electron collision experiments.
hep-ph/9403234
Nils A. Tornqvist
Nils A. T\"ornqvist
How to Parametrize an S-Wave Resonance and How to Identify Two-Hadron Composites
10 pages in Latex + 2 figures available on request. Helsinki preprint HU-SEFT R 1994-03
Phys.Rev. D51 (1995) 5312-5315
10.1103/PhysRevD.51.5312
null
hep-ph
null
The question of how one can distinguish quark model states from 2-hadron states near an S-wave theshold is discussed, and the usefulness of the running mass is emphasized as the meeting ground for experiment and theory and for defining resonance parameters.
[ { "created": "Mon, 7 Mar 1994 12:13:25 GMT", "version": "v1" } ]
2009-10-28
[ [ "Törnqvist", "Nils A.", "" ] ]
The question of how one can distinguish quark model states from 2-hadron states near an S-wave theshold is discussed, and the usefulness of the running mass is emphasized as the meeting ground for experiment and theory and for defining resonance parameters.
2303.04662
Abdulkadir Senol
M. K\"oksal, A. Senol, H. Denizli
Search for the electromagnetic properties of the neutrinos at the HL-LHC and the FCC-hh
14 pages, 6 figures, 2 tables, version accepted for publication in Physics Letters B
null
10.1016/j.physletb.2023.137914
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $\nu\bar{\nu}\gamma \gamma$ couplings parametrized with the non-standard dimension-seven operators defined by the Effective Field Theory framework are investigated through the process $pp\to \nu\bar{\nu}\gamma$ at the High Luminosity-LHC and the Future Circular proton-proton Collider. The effective Lagrangian of $\nu\bar{\nu}\gamma \gamma$ couplings is implemented into FeynRules to generate a UFO module inserted into Madgraph to generate both background and signal events. These events are then passed through Pythia 8 for parton showering and Delphes to include realistic detector effects. The sensitivities on $\nu\bar{\nu}\gamma \gamma$ couplings are obtained at $95\%$ confidence level. We show that the analysis of the signal emerging from the process $pp\to \nu\bar{\nu}\gamma$ allows to improve constraints on $\nu\bar{\nu}\gamma \gamma$ couplings given by the LEP collaboration.
[ { "created": "Wed, 8 Mar 2023 15:31:18 GMT", "version": "v1" }, { "created": "Tue, 18 Apr 2023 07:50:24 GMT", "version": "v2" } ]
2023-04-19
[ [ "Köksal", "M.", "" ], [ "Senol", "A.", "" ], [ "Denizli", "H.", "" ] ]
The $\nu\bar{\nu}\gamma \gamma$ couplings parametrized with the non-standard dimension-seven operators defined by the Effective Field Theory framework are investigated through the process $pp\to \nu\bar{\nu}\gamma$ at the High Luminosity-LHC and the Future Circular proton-proton Collider. The effective Lagrangian of $\nu\bar{\nu}\gamma \gamma$ couplings is implemented into FeynRules to generate a UFO module inserted into Madgraph to generate both background and signal events. These events are then passed through Pythia 8 for parton showering and Delphes to include realistic detector effects. The sensitivities on $\nu\bar{\nu}\gamma \gamma$ couplings are obtained at $95\%$ confidence level. We show that the analysis of the signal emerging from the process $pp\to \nu\bar{\nu}\gamma$ allows to improve constraints on $\nu\bar{\nu}\gamma \gamma$ couplings given by the LEP collaboration.
0909.2076
Michael Edmund Tobar
Michael E. Tobar, Eugene N. Ivanov, Paul L. Stanwix, Jean-Michel G. le Floch, John G. Hartnett
Rotating Odd-Parity Lorentz Invariance Test in Electrodynamics
null
null
10.1103/PhysRevD.80.125024
null
hep-ph gr-qc physics.ins-det
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report the first operation of a rotating odd-parity Lorentz Invariance test in electrodynamics using a microwave Mach-Zehnder interferometer with permeable material in one arm. The experiment sets a direct bound to $ \kappa_{tr}$ of $-0.3\pm 3\times10^{-7}$. Using new power recycled waveguide interferometer techniques (with the highest spectral resolution ever achieved of $2\times10^{-11} rad/\sqrt{Hz}$) we show an improvement of several orders of magnitude is attainable in the future.
[ { "created": "Fri, 11 Sep 2009 02:59:51 GMT", "version": "v1" }, { "created": "Wed, 25 Nov 2009 03:15:41 GMT", "version": "v2" } ]
2015-05-14
[ [ "Tobar", "Michael E.", "" ], [ "Ivanov", "Eugene N.", "" ], [ "Stanwix", "Paul L.", "" ], [ "Floch", "Jean-Michel G. le", "" ], [ "Hartnett", "John G.", "" ] ]
We report the first operation of a rotating odd-parity Lorentz Invariance test in electrodynamics using a microwave Mach-Zehnder interferometer with permeable material in one arm. The experiment sets a direct bound to $ \kappa_{tr}$ of $-0.3\pm 3\times10^{-7}$. Using new power recycled waveguide interferometer techniques (with the highest spectral resolution ever achieved of $2\times10^{-11} rad/\sqrt{Hz}$) we show an improvement of several orders of magnitude is attainable in the future.
hep-ph/9409389
null
C. A. A. Nunes, F. S. Navarra, P. Ring and M. Schaden
Nonperturbative effects in heavy quarkonia
Same results, but some conceptual ramifications and explanations. 32 pages. RevTex
null
null
null
hep-ph
null
An effective hamiltonian for heavy quarkonia is derived from QCD by separating gluonic fields in background and quantum fields and neglecting anharmonic contributions. Mesonic states with nonperturbative gluonic components are constructed. These states are invariant under gauge changes of the background fields and form an orthogonal basis. The effective hamiltonian is diagonalized in this basis in a systematic $1/m$- and short distance expansion. For very heavy quarkonia, we obtain an effective potential similar to the phenomenological funnel potential. We compare our method to $2^{\rm nd}$ order perturbation theory in the background fields and demonstrate its applicability even for the relatively light charmonium system. The results to order $1/m$ for pseudoscalar meson masses and wave functions are shown and compared with those of the Cornell model.
[ { "created": "Thu, 22 Sep 1994 11:34:20 GMT", "version": "v1" }, { "created": "Fri, 23 Sep 1994 11:29:52 GMT", "version": "v2" }, { "created": "Tue, 22 Nov 1994 20:16:04 GMT", "version": "v3" } ]
2009-09-25
[ [ "Nunes", "C. A. A.", "" ], [ "Navarra", "F. S.", "" ], [ "Ring", "P.", "" ], [ "Schaden", "M.", "" ] ]
An effective hamiltonian for heavy quarkonia is derived from QCD by separating gluonic fields in background and quantum fields and neglecting anharmonic contributions. Mesonic states with nonperturbative gluonic components are constructed. These states are invariant under gauge changes of the background fields and form an orthogonal basis. The effective hamiltonian is diagonalized in this basis in a systematic $1/m$- and short distance expansion. For very heavy quarkonia, we obtain an effective potential similar to the phenomenological funnel potential. We compare our method to $2^{\rm nd}$ order perturbation theory in the background fields and demonstrate its applicability even for the relatively light charmonium system. The results to order $1/m$ for pseudoscalar meson masses and wave functions are shown and compared with those of the Cornell model.
1210.0263
Marcelo Miguel Miller Bertolami
Brenda Melendez, Marcelo Miller Bertolami, and Leandro Althaus
Revisiting the Impact of Axions in the Cooling of White Dwarfs
To be published in the proceedings of the 18th European White Dwarf Workshop. 4 pages, 2 figures
null
null
null
hep-ph astro-ph.SR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It has been shown that the shape of the luminosity function of white dwarfs can be a powerful tool to check for the possible existence of DFSZ-axions. In particular, Isern et al. (2008) showed that, if the axion mass is of the order of a few meV, then the white dwarf luminosity function is sensitive enough to detect their existence. For axion masses of about $m_a > 5$ meV the axion emission can be a primary cooling mechanism for the white dwarf and the feedback of the axion emission into the thermal structure of the white dwarf needs to be considered. Here we present computations of white dwarf cooling sequences that take into account the effect of axion emission in a self consistent way by means of full stellar evolution computations. Then, we study and discuss the impact of the axion emission in the white dwarf luminosity function.
[ { "created": "Mon, 1 Oct 2012 00:28:58 GMT", "version": "v1" } ]
2012-10-02
[ [ "Melendez", "Brenda", "" ], [ "Bertolami", "Marcelo Miller", "" ], [ "Althaus", "Leandro", "" ] ]
It has been shown that the shape of the luminosity function of white dwarfs can be a powerful tool to check for the possible existence of DFSZ-axions. In particular, Isern et al. (2008) showed that, if the axion mass is of the order of a few meV, then the white dwarf luminosity function is sensitive enough to detect their existence. For axion masses of about $m_a > 5$ meV the axion emission can be a primary cooling mechanism for the white dwarf and the feedback of the axion emission into the thermal structure of the white dwarf needs to be considered. Here we present computations of white dwarf cooling sequences that take into account the effect of axion emission in a self consistent way by means of full stellar evolution computations. Then, we study and discuss the impact of the axion emission in the white dwarf luminosity function.
1005.0355
Graeme Watt
H. Kowalski, L.N. Lipatov, D.A. Ross, G. Watt
Using HERA Data to Determine the Infrared Behaviour of the BFKL Amplitude
30 pages, 11 figures. v2: revised version published in Eur. Phys. J. C
Eur.Phys.J.C70:983-998,2010
10.1140/epjc/s10052-010-1500-6
DESY 10-061, SHEP-10-04, CERN-PH-TH/2010-091
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We determine the infrared behaviour of the BFKL forward amplitude for gluon-gluon scattering. Our approach, based on the discrete pomeron solution, leads to an excellent description of the new combined inclusive HERA data at low values of x (<0.01) and at the same time determines the unintegrated gluon density inside the proton, for squared transverse momenta of the gluon less than 100 GeV^2. The phases of this amplitude are sensitive to the non-perturbative gluonic dynamics and could be sensitive to the presence of Beyond-the-Standard-Model particles at very high energies.
[ { "created": "Mon, 3 May 2010 17:39:34 GMT", "version": "v1" }, { "created": "Mon, 22 Nov 2010 09:01:43 GMT", "version": "v2" } ]
2010-12-14
[ [ "Kowalski", "H.", "" ], [ "Lipatov", "L. N.", "" ], [ "Ross", "D. A.", "" ], [ "Watt", "G.", "" ] ]
We determine the infrared behaviour of the BFKL forward amplitude for gluon-gluon scattering. Our approach, based on the discrete pomeron solution, leads to an excellent description of the new combined inclusive HERA data at low values of x (<0.01) and at the same time determines the unintegrated gluon density inside the proton, for squared transverse momenta of the gluon less than 100 GeV^2. The phases of this amplitude are sensitive to the non-perturbative gluonic dynamics and could be sensitive to the presence of Beyond-the-Standard-Model particles at very high energies.
1203.2489
Sabine Kraml
S. Kraml, B. C. Allanach, M. Mangano, H. B. Prosper, S. Sekmen (editors), C. Balazs, A. Barr, P. Bechtle, G. Belanger, A. Belyaev, K. Benslama, M. Campanelli, K. Cranmer, A. De Roeck, M. J. Dolan, T. Eifert, J. R. Ellis, M. Felcini, B. Fuks, D. Guadagnoli, J. F. Gunion, S. Heinemeyer, J. Hewett, A. Ismail, M. Kadastik, M. Kramer, J. Lykken, F. Mahmoudi, S. P. Martin, T. Rizzo, T. Robens, M. Tytgat, A. Weiler
Searches for New Physics: Les Houches Recommendations for the Presentation of LHC Results
17 pages, no figures; v2: author added
Eur. Phys. J. C 72 (2012) 1976
10.1140/epjc/s10052-012-1976-3
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a set of recommendations for the presentation of LHC results on searches for new physics, which are aimed at providing a more efficient flow of scientific information between the experimental collaborations and the rest of the high energy physics community, and at facilitating the interpretation of the results in a wide class of models. Implementing these recommendations would aid the full exploitation of the physics potential of the LHC.
[ { "created": "Mon, 12 Mar 2012 13:43:05 GMT", "version": "v1" }, { "created": "Tue, 20 Mar 2012 18:30:04 GMT", "version": "v2" } ]
2012-05-16
[ [ "Kraml", "S.", "", "editors" ], [ "Allanach", "B. C.", "", "editors" ], [ "Mangano", "M.", "", "editors" ], [ "Prosper", "H. B.", "", "editors" ], [ "Sekmen", "S.", "", "editors" ], [ "Balazs", "C.", "" ], [ "Barr", "A.", "" ], [ "Bechtle", "P.", "" ], [ "Belanger", "G.", "" ], [ "Belyaev", "A.", "" ], [ "Benslama", "K.", "" ], [ "Campanelli", "M.", "" ], [ "Cranmer", "K.", "" ], [ "De Roeck", "A.", "" ], [ "Dolan", "M. J.", "" ], [ "Eifert", "T.", "" ], [ "Ellis", "J. R.", "" ], [ "Felcini", "M.", "" ], [ "Fuks", "B.", "" ], [ "Guadagnoli", "D.", "" ], [ "Gunion", "J. F.", "" ], [ "Heinemeyer", "S.", "" ], [ "Hewett", "J.", "" ], [ "Ismail", "A.", "" ], [ "Kadastik", "M.", "" ], [ "Kramer", "M.", "" ], [ "Lykken", "J.", "" ], [ "Mahmoudi", "F.", "" ], [ "Martin", "S. P.", "" ], [ "Rizzo", "T.", "" ], [ "Robens", "T.", "" ], [ "Tytgat", "M.", "" ], [ "Weiler", "A.", "" ] ]
We present a set of recommendations for the presentation of LHC results on searches for new physics, which are aimed at providing a more efficient flow of scientific information between the experimental collaborations and the rest of the high energy physics community, and at facilitating the interpretation of the results in a wide class of models. Implementing these recommendations would aid the full exploitation of the physics potential of the LHC.
0710.2883
Christopher Smith
Christopher Smith
What rare K decays can tell about the MSSM
Submitted for the SUSY07 proceedings, 4 pages, 2 figures
null
null
null
hep-ph
null
The supersymmetric contributions to the theoretically clean K+ --> pi+ nu nu bar, KL --> pi0 nu nu bar, KL --> pi0 e+ e- and KL --> pi0 mu+ mu- decays are briefly reviewed. Particular emphasis is laid on the information one could get on the MSSM flavor sector from a combined study of the four modes.
[ { "created": "Mon, 15 Oct 2007 17:48:11 GMT", "version": "v1" }, { "created": "Tue, 23 Oct 2007 09:09:44 GMT", "version": "v2" } ]
2007-10-23
[ [ "Smith", "Christopher", "" ] ]
The supersymmetric contributions to the theoretically clean K+ --> pi+ nu nu bar, KL --> pi0 nu nu bar, KL --> pi0 e+ e- and KL --> pi0 mu+ mu- decays are briefly reviewed. Particular emphasis is laid on the information one could get on the MSSM flavor sector from a combined study of the four modes.
1606.06502
Michael Trott
Mikkel Bj{\o}rn and Michael Trott
Interpreting $W$ mass measurements in the SMEFT
6pp, 4 figures V2: minor typo corrections and text clarifications, matches journal version
null
10.1016/j.physletb.2016.10.003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Measurements of the $W^\pm$ mass ($m_W$) provide an important consistency check of the Standard Model (SM) and constrain the possibility of physics beyond the SM. Precision measurements of $m_W$ at hadron colliders are inferred from kinematic distributions of transverse variables. We examine how this inference is modified when considering the presence of physics beyond the SM expressed in terms of local contact operators. We show that Tevatron measurements of $m_W$ using transverse variables are transparent and applicable as consistent constraints in the Standard Model Effective Field Theory (SMEFT) with small measurement bias. This means that the leading challenge to interpreting these measurements in the SMEFT is the pure theoretical uncertainty in how these measurements are mapped to Lagrangian parameters. We stress the need to avoid using naive combinations of Tevatron and LEPII measurements of $m_W$ without the introduction of any SMEFT theoretical error to avoid implicit UV assumptions. In a companion paper, we implement our procedure to consistently incorporate $m_W$ measurements into a global fit.
[ { "created": "Tue, 21 Jun 2016 10:42:50 GMT", "version": "v1" }, { "created": "Fri, 30 Sep 2016 07:28:36 GMT", "version": "v2" } ]
2016-10-07
[ [ "Bjørn", "Mikkel", "" ], [ "Trott", "Michael", "" ] ]
Measurements of the $W^\pm$ mass ($m_W$) provide an important consistency check of the Standard Model (SM) and constrain the possibility of physics beyond the SM. Precision measurements of $m_W$ at hadron colliders are inferred from kinematic distributions of transverse variables. We examine how this inference is modified when considering the presence of physics beyond the SM expressed in terms of local contact operators. We show that Tevatron measurements of $m_W$ using transverse variables are transparent and applicable as consistent constraints in the Standard Model Effective Field Theory (SMEFT) with small measurement bias. This means that the leading challenge to interpreting these measurements in the SMEFT is the pure theoretical uncertainty in how these measurements are mapped to Lagrangian parameters. We stress the need to avoid using naive combinations of Tevatron and LEPII measurements of $m_W$ without the introduction of any SMEFT theoretical error to avoid implicit UV assumptions. In a companion paper, we implement our procedure to consistently incorporate $m_W$ measurements into a global fit.
2401.04142
Cheuk-Yin Wong
Cheuk-Yin Wong
QED meson description of the anomalous particles at ~17 and ~38 MeV
39 pages, based on a talk presented at 52nd International Symposium on Multiparticle Dynamics, at Gy\"ongy\"os, Hungary, August 20-26, 2023
Universe (2024), 10, 173
10.3390/universe10040173
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The Schwinger confinement mechanism stipulates that a massless fermion and a massless antifermion are confined as a massive boson when they interact in the Abelian QED interaction in (1+1)D. If we approximate light quarks as massless and apply the Schwinger confinement mechanism to quarks, we can infer that a light quark and a light antiquark interacting in the Abelian QED interaction are confined as a QED meson in (1+1)D. Similarly, a light quark and a light antiquark interacting in the QCD interaction in the quasi-Abelian approximation will be confined as a QCD meson in (1+1)D. The QED and QCD mesons in (1+1)D can represent physical mesons in (3+1)D when the flux tube radius is properly taken into account. Such a theory leads to a reasonable description of the masses of $\pi^0, \eta$, and $ \eta'$, and its extrapolation to the unknown QED sector yields an isoscalar QED meson at about 17 MeV and an isovector QED meson at about 38 MeV. The observations of the anomalous soft photons, the hypothetical X17 particle, and the hypothetical E38 particle bear promising evidence for the possible existence of the QED mesons. Pending further confirmation, they hold important implications on the properties on the quarks and their interactions.
[ { "created": "Sun, 7 Jan 2024 17:17:26 GMT", "version": "v1" }, { "created": "Sun, 11 Feb 2024 15:47:30 GMT", "version": "v2" }, { "created": "Wed, 10 Apr 2024 14:12:50 GMT", "version": "v3" } ]
2024-04-11
[ [ "Wong", "Cheuk-Yin", "" ] ]
The Schwinger confinement mechanism stipulates that a massless fermion and a massless antifermion are confined as a massive boson when they interact in the Abelian QED interaction in (1+1)D. If we approximate light quarks as massless and apply the Schwinger confinement mechanism to quarks, we can infer that a light quark and a light antiquark interacting in the Abelian QED interaction are confined as a QED meson in (1+1)D. Similarly, a light quark and a light antiquark interacting in the QCD interaction in the quasi-Abelian approximation will be confined as a QCD meson in (1+1)D. The QED and QCD mesons in (1+1)D can represent physical mesons in (3+1)D when the flux tube radius is properly taken into account. Such a theory leads to a reasonable description of the masses of $\pi^0, \eta$, and $ \eta'$, and its extrapolation to the unknown QED sector yields an isoscalar QED meson at about 17 MeV and an isovector QED meson at about 38 MeV. The observations of the anomalous soft photons, the hypothetical X17 particle, and the hypothetical E38 particle bear promising evidence for the possible existence of the QED mesons. Pending further confirmation, they hold important implications on the properties on the quarks and their interactions.
1910.03959
Martin Simon
M. C. Simon (on behalf of the ASACUSA collaboration)
Rabi Experiments on the $\sigma$ and $\pi$ Hyperfine Transitions in Hydrogen and Status of ASACUSA's Antihydrogen Program
Presented at the Eighth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, May 12-16, 2019
null
null
null
hep-ph hep-ex physics.atom-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on the status of the in-beam hyperfine-structure measurements on ground-state antihydrogen by ASACUSA and on recent results obtained in supporting measurements from hydrogen. The $\sigma_1$ and $\pi_1$ transitions can now be investigated, which is beneficial from both theoretical and experimental perspectives. We discuss systematic effects from resonance interference originating from the chosen field geometries in the interaction region, and how their impact can be managed by appropriate data-taking or design concepts.
[ { "created": "Wed, 9 Oct 2019 12:49:53 GMT", "version": "v1" }, { "created": "Wed, 16 Oct 2019 08:08:32 GMT", "version": "v2" } ]
2019-10-17
[ [ "Simon", "M. C.", "", "on behalf of the ASACUSA collaboration" ] ]
We report on the status of the in-beam hyperfine-structure measurements on ground-state antihydrogen by ASACUSA and on recent results obtained in supporting measurements from hydrogen. The $\sigma_1$ and $\pi_1$ transitions can now be investigated, which is beneficial from both theoretical and experimental perspectives. We discuss systematic effects from resonance interference originating from the chosen field geometries in the interaction region, and how their impact can be managed by appropriate data-taking or design concepts.
hep-ph/0509323
Yuryi A. Tarasov
Yu.A. Tarasov and S.L. Fokin
Suppression of $\pi^0$ production at large $p_\perp$ in central $Au +Au$ collisions at $\sqrt{s_{NN}} = 200$ GeV and quark-gluon plasma
14 pages, 4 figures
null
null
null
hep-ph
null
We investigate the suppression of $\pi^0$-spectrum in a wide range of $p_\perp$ up 60 GeV/c which is caused by the energy loss of the gluon and quark jets in quark-gluon plasma. The physical characteristics of initial and mixed phases were found in the effective quasiparticle model by analogy with previous work \cite{5}. The PHENIX data up 10 GeV/c within the limits of precision are described by quasiparticle model with decrease of the thermal gluon mass and effective coupling in the region of phase transitin (at $T\to T_c$ from above). We also take into account the intrinsic transverse momentum $k_\perp$ of partons. The suppression factor $R_{AA}(p_\perp)$ shows the weak rise with increase of $p_\perp$ above 4 GeV/c, then it reaches smooth maximum at $p_\perp \sim 20$ GeV/c and then decrease at $p_\perp\sim 60$ GeV/c again to value $R_{AA}$ at $p_\perp\simeq$ 4 GeV/c. The factor $R_{AA}$ in this range of $p_\perp$ is changihg weakly if intrinsic momentum $k_\perp$ is taken into account.
[ { "created": "Wed, 28 Sep 2005 12:42:49 GMT", "version": "v1" } ]
2016-09-06
[ [ "Tarasov", "Yu. A.", "" ], [ "Fokin", "S. L.", "" ] ]
We investigate the suppression of $\pi^0$-spectrum in a wide range of $p_\perp$ up 60 GeV/c which is caused by the energy loss of the gluon and quark jets in quark-gluon plasma. The physical characteristics of initial and mixed phases were found in the effective quasiparticle model by analogy with previous work \cite{5}. The PHENIX data up 10 GeV/c within the limits of precision are described by quasiparticle model with decrease of the thermal gluon mass and effective coupling in the region of phase transitin (at $T\to T_c$ from above). We also take into account the intrinsic transverse momentum $k_\perp$ of partons. The suppression factor $R_{AA}(p_\perp)$ shows the weak rise with increase of $p_\perp$ above 4 GeV/c, then it reaches smooth maximum at $p_\perp \sim 20$ GeV/c and then decrease at $p_\perp\sim 60$ GeV/c again to value $R_{AA}$ at $p_\perp\simeq$ 4 GeV/c. The factor $R_{AA}$ in this range of $p_\perp$ is changihg weakly if intrinsic momentum $k_\perp$ is taken into account.
1502.05761
Stefano Moretti Prof
Nils-Erik Bomark (Warsaw, Inst. Nucl. Studies), Stefano Moretti (Southampton U.), Shoaib Munir (APCTP, Pohang & Uppsala U.), Leszek Roszkowski (Warsaw, Inst. Nucl. Studies and Sheffield U.)
A light NMSSM pseudoscalar Higgs boson at the LHC Run 2
6 pages, 6 figures, 1 table - Talk given at the Toyama International Workshop on Higgs as a Probe of New Physics 2015, 11-15, February, 2015, Toyama, Japan
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the light pseudoscalar $A_1$ in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) with partial universality at some high unification scale in order to delineate the parameter space regions consistent with up-to-date theoretical and experimental constraints and examine to what extent this state can be probed by the Large Hadron Collider (LHC) during Run 2. We find that it can be accessible through a variety of signatures proceeding via $A_1\to \tau^+\tau^-$ and/or $b\bar b$, the former assuming hadronic decays and the latter two $b$-tags within a fat jet or two separate slim ones. Herein, the light pseudoscalar state is produced from a heavy Higgs boson decay in either pairs or singly in association with a $Z$ boson (in turn decaying into electrons/muons).
[ { "created": "Fri, 20 Feb 2015 01:51:06 GMT", "version": "v1" } ]
2015-02-23
[ [ "Bomark", "Nils-Erik", "", "Warsaw, Inst. Nucl. Studies" ], [ "Moretti", "Stefano", "", "Southampton U." ], [ "Munir", "Shoaib", "", "APCTP, Pohang & Uppsala U." ], [ "Roszkowski", "Leszek", "", "Warsaw, Inst. Nucl. Studies and Sheffield U." ] ]
We revisit the light pseudoscalar $A_1$ in the Next-to-Minimal Supersymmetric Standard Model (NMSSM) with partial universality at some high unification scale in order to delineate the parameter space regions consistent with up-to-date theoretical and experimental constraints and examine to what extent this state can be probed by the Large Hadron Collider (LHC) during Run 2. We find that it can be accessible through a variety of signatures proceeding via $A_1\to \tau^+\tau^-$ and/or $b\bar b$, the former assuming hadronic decays and the latter two $b$-tags within a fat jet or two separate slim ones. Herein, the light pseudoscalar state is produced from a heavy Higgs boson decay in either pairs or singly in association with a $Z$ boson (in turn decaying into electrons/muons).
1812.06041
William A. Bardeen
William A. Bardeen
Instanton Triggered Chiral Symmetry Breaking, the U(1) Problem and a Possible Solution to the Strong CP Problem
6 pages
null
null
FERMILAB-Pub-18-683-T
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We argue that instantons play a crucial role in triggering the spontaneous breaking of chiral symmetry in the physics of the three light quarks in quantum chromodynamics. However, instantons may also play an essential role in our understanding of the suppression of CP violation in the strong interactions. We revive the possibility that the bare mass of the up quark is identically zero and the apparent small up quark mass is generated by the effective quark dynamics associated with instantons. In this case, the strong CP phase becomes unobservable and there is no strong CP violation.
[ { "created": "Fri, 14 Dec 2018 17:29:26 GMT", "version": "v1" }, { "created": "Tue, 18 Dec 2018 19:37:02 GMT", "version": "v2" } ]
2018-12-20
[ [ "Bardeen", "William A.", "" ] ]
We argue that instantons play a crucial role in triggering the spontaneous breaking of chiral symmetry in the physics of the three light quarks in quantum chromodynamics. However, instantons may also play an essential role in our understanding of the suppression of CP violation in the strong interactions. We revive the possibility that the bare mass of the up quark is identically zero and the apparent small up quark mass is generated by the effective quark dynamics associated with instantons. In this case, the strong CP phase becomes unobservable and there is no strong CP violation.
0907.1349
Xiang Liu
Xiang Liu and Hong-Wei Ke
The line shape of the radiative open-charm decay of Y(4140) and Y(3930)
4 pages, 4 figures. More references and discussions added, typos corrected. Accepted by Phys. Rev. D
Phys.Rev.D80:034009,2009
10.1103/PhysRevD.80.034009
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we study the radiative open-charm decays $Y(4140)\to {D}_s^{\ast+} D_s^- \gamma$ and $Y(3930)\to{D}^{\ast+} D^-\gamma$ under the assignments of $D_{s}^*\bar{D}_s^*$ and $D^*\bar{D}^*$ as molecular states for Y(4140) and Y(3930) respectively. Based on our numerical result, we propose the experimental measurement of the photon spectrum of $Y(4140)\to {D}_s^{\ast+} D_s^- \gamma, D_{s}^+D_{s}^{*-}\gamma$ and $Y(3930)\to D^{*0}\bar{D}^0\gamma, D^{0}\bar{D}^{*0}\gamma, D^{*+}D^-\gamma, D^+D^{*-}\gamma$ can further test the molecular assignment for Y(4140) and Y(3930).
[ { "created": "Wed, 8 Jul 2009 07:43:07 GMT", "version": "v1" }, { "created": "Mon, 20 Jul 2009 07:29:06 GMT", "version": "v2" } ]
2009-08-10
[ [ "Liu", "Xiang", "" ], [ "Ke", "Hong-Wei", "" ] ]
In this work, we study the radiative open-charm decays $Y(4140)\to {D}_s^{\ast+} D_s^- \gamma$ and $Y(3930)\to{D}^{\ast+} D^-\gamma$ under the assignments of $D_{s}^*\bar{D}_s^*$ and $D^*\bar{D}^*$ as molecular states for Y(4140) and Y(3930) respectively. Based on our numerical result, we propose the experimental measurement of the photon spectrum of $Y(4140)\to {D}_s^{\ast+} D_s^- \gamma, D_{s}^+D_{s}^{*-}\gamma$ and $Y(3930)\to D^{*0}\bar{D}^0\gamma, D^{0}\bar{D}^{*0}\gamma, D^{*+}D^-\gamma, D^+D^{*-}\gamma$ can further test the molecular assignment for Y(4140) and Y(3930).
0912.4722
Jusak Tandean
Xiao-Gang He, Tong Li, Xue-Qian Li, Jusak Tandean, Ho-Chin Tsai
The Simplest Dark-Matter Model, CDMS II Results, and Higgs Detection at LHC
10 pages, 5 figures; results updated with WMAP7 input, references added, conclusions unchanged, to match published version
Phys.Lett.B688:332-336,2010
10.1016/j.physletb.2010.04.026
null
hep-ph astro-ph.CO hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The direct-search experiment for dark matter performed by the CDMS II Collaboration has observed two candidate events. Although these events cannot be interpreted as significant evidence for the presence of weakly interacting massive particle (WIMP) dark matter (DM), the total CDMS II data have led to an improved upper-limit on the WIMP-nucleon spin-independent cross-section. We study some implications of these results for the simplest WIMP DM model, the SM+D, which extends the standard model (SM) by the addition of a real SM-singlet scalar field dubbed darkon to play the role of the DM. We find that, although the CDMS II data rule out a sizable portion of parameter space of the model, a large part of the parameter space is still allowed. We obtain strong correlations among the darkon mass, darkon-nucleon cross-section, mass of the Higgs boson, and branching ratio of its invisible decay. We point out that measurements of the Higgs invisible branching-ratio at the LHC can lift some possible ambiguities in determining the darkon mass from direct DM searches.
[ { "created": "Wed, 23 Dec 2009 20:28:10 GMT", "version": "v1" }, { "created": "Wed, 30 Dec 2009 08:15:49 GMT", "version": "v2" }, { "created": "Wed, 28 Apr 2010 18:52:10 GMT", "version": "v3" } ]
2010-05-07
[ [ "He", "Xiao-Gang", "" ], [ "Li", "Tong", "" ], [ "Li", "Xue-Qian", "" ], [ "Tandean", "Jusak", "" ], [ "Tsai", "Ho-Chin", "" ] ]
The direct-search experiment for dark matter performed by the CDMS II Collaboration has observed two candidate events. Although these events cannot be interpreted as significant evidence for the presence of weakly interacting massive particle (WIMP) dark matter (DM), the total CDMS II data have led to an improved upper-limit on the WIMP-nucleon spin-independent cross-section. We study some implications of these results for the simplest WIMP DM model, the SM+D, which extends the standard model (SM) by the addition of a real SM-singlet scalar field dubbed darkon to play the role of the DM. We find that, although the CDMS II data rule out a sizable portion of parameter space of the model, a large part of the parameter space is still allowed. We obtain strong correlations among the darkon mass, darkon-nucleon cross-section, mass of the Higgs boson, and branching ratio of its invisible decay. We point out that measurements of the Higgs invisible branching-ratio at the LHC can lift some possible ambiguities in determining the darkon mass from direct DM searches.
hep-ph/0301076
Mikhail Voloshin
M.B. Voloshin
Variation of the relative yield of charged and neutral B mesons across the Upsilon(4S) resonance
10 pages
Mod.Phys.Lett. A18 (2003) 1783-1792
10.1142/S0217732303011538
TPI-MINN-03/01-T, UMN-TH-2125-03
hep-ph
null
It is shown that the ratio of the production rates of the pairs (B+ B-) and (B0 anti-B0) should experience a substantial and rapid variation with energy within the width of the Upsilon(4S) resonance, crossing the value of one near the center of the resonance. This behavior is due to an interference of the rapidly changing with energy Breit-Wigner phase with the phase introduced in the wave function of charged mesons by their Coulomb interaction.
[ { "created": "Mon, 13 Jan 2003 17:00:28 GMT", "version": "v1" } ]
2009-11-10
[ [ "Voloshin", "M. B.", "" ] ]
It is shown that the ratio of the production rates of the pairs (B+ B-) and (B0 anti-B0) should experience a substantial and rapid variation with energy within the width of the Upsilon(4S) resonance, crossing the value of one near the center of the resonance. This behavior is due to an interference of the rapidly changing with energy Breit-Wigner phase with the phase introduced in the wave function of charged mesons by their Coulomb interaction.
hep-ph/0607099
Vadim Guzey
V. Guzey, T. Teckentrup
The dual parameterization of the proton generalized parton distribution functions H and E and description of the DVCS cross sections and asymmetries
33 pages, 11 figures
Phys.Rev. D74 (2006) 054027
10.1103/PhysRevD.74.054027
RUB-TP2-04/2006
hep-ph
null
We develop the minimal model of a new leading order parameterization of GPDs introduced by Shuvaev and Polyakov. The model for GPDs H and E is formulated in terms of the forward quark distributions, the Gegenbauer moments of the D-term and the forward limit of the GPD E. The model is designed primarely for small and medium-size values of x_B, x_B \leq 0.2. We examined two different models of the t-dependence of the GPDs: The factorized exponential model and the non-factorized Regge-motivated model. Using our model, we successfully described the DVCS cross section measured by H1 and ZEUS, the moments of the beam-spin A_{LU}^{\sin \phi}, beam-charge A_{C}^{\cos \phi} and transversely-polarized target A_{UT}^{\sin \phi \cos \phi} DVCS asymmetries measured by HERMES and A_{LU}^{\sin \phi} measured by CLAS. The data on A_{C}^{\cos \phi} prefers the Regge-motivated model of the t-dependence of the GPDs. The data on A_{UT}^{\sin \phi \cos \phi} indicates that the u and d quarks carry only a small fraction of the proton total angular momentum.
[ { "created": "Mon, 10 Jul 2006 08:43:41 GMT", "version": "v1" } ]
2009-11-11
[ [ "Guzey", "V.", "" ], [ "Teckentrup", "T.", "" ] ]
We develop the minimal model of a new leading order parameterization of GPDs introduced by Shuvaev and Polyakov. The model for GPDs H and E is formulated in terms of the forward quark distributions, the Gegenbauer moments of the D-term and the forward limit of the GPD E. The model is designed primarely for small and medium-size values of x_B, x_B \leq 0.2. We examined two different models of the t-dependence of the GPDs: The factorized exponential model and the non-factorized Regge-motivated model. Using our model, we successfully described the DVCS cross section measured by H1 and ZEUS, the moments of the beam-spin A_{LU}^{\sin \phi}, beam-charge A_{C}^{\cos \phi} and transversely-polarized target A_{UT}^{\sin \phi \cos \phi} DVCS asymmetries measured by HERMES and A_{LU}^{\sin \phi} measured by CLAS. The data on A_{C}^{\cos \phi} prefers the Regge-motivated model of the t-dependence of the GPDs. The data on A_{UT}^{\sin \phi \cos \phi} indicates that the u and d quarks carry only a small fraction of the proton total angular momentum.
2007.09283
Eduardo Folco Capossoli
Eduardo Folco Capossoli, Miguel Angel Mart\'in Contreras, Danning Li, Alfredo Vega and Henrique Boschi-Filho
Proton Structure Functions from an AdS/QCD model with a deformed background
V2: 25 pages, 6 figures, 1 table. Text improved. Typos corrected. New references added. Results unchanged. This version matches the published one in PRD
Phys. Rev. D 102, 086004 (2020)
10.1103/PhysRevD.102.086004
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we study unpolarized spin $1/2$ baryonic deep inelastic scattering (DIS) in the regime of large Bjorken parameter $x$. We calculate the corresponding structure functions $F_{1,2}(x,q^2)$. Our approach is based on an AdS/QCD model with a deformed background, where we consider an exponential factor in the AdS$_5$ metric. Such a deformation implies the introduction of an anomalous dimension in the model. Our results for the structure functions are consistent with those found in the literature from experimental data.
[ { "created": "Fri, 17 Jul 2020 23:50:43 GMT", "version": "v1" }, { "created": "Tue, 6 Oct 2020 03:03:25 GMT", "version": "v2" } ]
2020-10-07
[ [ "Capossoli", "Eduardo Folco", "" ], [ "Contreras", "Miguel Angel Martín", "" ], [ "Li", "Danning", "" ], [ "Vega", "Alfredo", "" ], [ "Boschi-Filho", "Henrique", "" ] ]
In this work we study unpolarized spin $1/2$ baryonic deep inelastic scattering (DIS) in the regime of large Bjorken parameter $x$. We calculate the corresponding structure functions $F_{1,2}(x,q^2)$. Our approach is based on an AdS/QCD model with a deformed background, where we consider an exponential factor in the AdS$_5$ metric. Such a deformation implies the introduction of an anomalous dimension in the model. Our results for the structure functions are consistent with those found in the literature from experimental data.
1105.4103
Larry McLerran
Larry McLerran
Happy Island
Invited talk presented at Symposium on Nuclear Physics in GOA, India, Nov. 28-Dec. 2, 2010
null
10.1142/9789814355766_0007
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I discuss the phase diagram for QCD in the baryon chemical potential and temperature plane. I argue that there is a new phase of matter different from the deconfined Quark Gluon Plasma: Quarkyonic Matter. Quarkyonic Matter is confined and exists at densities parametrically large compared to the QCD scale, when the number of quark colors, $N_c$ is large. I motivate the possibility that Quarkyonic Matter is in an inhomogeneous phase, and is surrounded by lines of phase transitions, making a Happy Island in the $\mu_B$-T plane. I conjecture about the geography of Happy Island.
[ { "created": "Fri, 20 May 2011 14:23:52 GMT", "version": "v1" } ]
2017-08-23
[ [ "McLerran", "Larry", "" ] ]
I discuss the phase diagram for QCD in the baryon chemical potential and temperature plane. I argue that there is a new phase of matter different from the deconfined Quark Gluon Plasma: Quarkyonic Matter. Quarkyonic Matter is confined and exists at densities parametrically large compared to the QCD scale, when the number of quark colors, $N_c$ is large. I motivate the possibility that Quarkyonic Matter is in an inhomogeneous phase, and is surrounded by lines of phase transitions, making a Happy Island in the $\mu_B$-T plane. I conjecture about the geography of Happy Island.
1408.0138
Avelino Vicente
A. Abada, M. E. Krauss, W. Porod, F. Staub, A. Vicente, C. Weiland
Lepton flavor violation in low-scale seesaw models: SUSY and non-SUSY contributions
75 pages, 7 figures. v3: references and comments added. Matches published version
JHEP 11 (2014) 048
10.1007/JHEP11(2014)048
LPT-Orsay-14-43, BONN-TH-14-11, IFT-UAM/CSIC-14-061, FTUAM-14-25
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Taking the supersymmetric inverse seesaw mechanism as the explanation for neutrino oscillation data, we investigate charged lepton flavor violation in radiative and 3-body lepton decays as well as in neutrinoless $\mu-e$ conversion in muonic atoms. In contrast to former studies, we take into account all possible contributions: supersymmetric as well as non-supersymmetric. We take CMSSM-like boundary conditions for the soft supersymmetry breaking parameters. We find several regions where cancellations between various contributions exist, reducing the lepton flavor violating rates by an order of magnitude compared to the case where only the dominant contribution is taken into account. This is in particular important for the correct interpretation of existing data as well as for estimating the reach of near future experiments where the sensitivity will be improved by one to two orders of magnitude. Moreover, we demonstrate that ratios like BR($\tau\to 3 \mu$)/BR($\tau\to \mu e^+ e^-$) can be used to determine whether the supersymmetric contributions dominate over the $W^\pm$ and $H^\pm$ contributions or vice versa.
[ { "created": "Fri, 1 Aug 2014 11:51:09 GMT", "version": "v1" }, { "created": "Fri, 5 Sep 2014 21:38:04 GMT", "version": "v2" }, { "created": "Mon, 17 Nov 2014 11:19:57 GMT", "version": "v3" } ]
2014-11-18
[ [ "Abada", "A.", "" ], [ "Krauss", "M. E.", "" ], [ "Porod", "W.", "" ], [ "Staub", "F.", "" ], [ "Vicente", "A.", "" ], [ "Weiland", "C.", "" ] ]
Taking the supersymmetric inverse seesaw mechanism as the explanation for neutrino oscillation data, we investigate charged lepton flavor violation in radiative and 3-body lepton decays as well as in neutrinoless $\mu-e$ conversion in muonic atoms. In contrast to former studies, we take into account all possible contributions: supersymmetric as well as non-supersymmetric. We take CMSSM-like boundary conditions for the soft supersymmetry breaking parameters. We find several regions where cancellations between various contributions exist, reducing the lepton flavor violating rates by an order of magnitude compared to the case where only the dominant contribution is taken into account. This is in particular important for the correct interpretation of existing data as well as for estimating the reach of near future experiments where the sensitivity will be improved by one to two orders of magnitude. Moreover, we demonstrate that ratios like BR($\tau\to 3 \mu$)/BR($\tau\to \mu e^+ e^-$) can be used to determine whether the supersymmetric contributions dominate over the $W^\pm$ and $H^\pm$ contributions or vice versa.
hep-ph/0103120
Stefan Recksiegel
A.G. Akeroyd, Y.-Y. Keum and S. Recksiegel
Direct CP Asymmetry of B -> X_d \gamma in the effective SUSY model
To appear in the proceedings of BCP4, Ise 2001. The original conference poster is available at http://www-th.kek.jp/home/stefan/b2dgamma/
null
null
null
hep-ph
null
We investigate the effect of supersymmetric CP violating phases on the inclusive decay B\to X_d\gamma. Although such a decay contains a large background from B\to X_s\gamma, if isolated it may exhibit sizeable CP violation, both in the Standard Model (SM) and in the context of models beyond the SM. With unconstrained supersymmetric CP violating phases we show that the direct CP asymmetry (A_CP) lies in the region -40% \le A_CP \le 40%, where a positive asymmetry would constitute a clear signal of physics beyond the SM. Even if a direct measurement of B\to X_d\gamma proves too dif ficult experimentally, its asymmetry contributes non-negligibly to the measurements of A_CP for B\to X_s\gamma, and thus should be included in future analyses. We show t hat there may be both constructive and destructive interference between A^d\gamma_CP and A^s\gamma_CP.
[ { "created": "Mon, 12 Mar 2001 12:08:19 GMT", "version": "v1" } ]
2007-05-23
[ [ "Akeroyd", "A. G.", "" ], [ "Keum", "Y. -Y.", "" ], [ "Recksiegel", "S.", "" ] ]
We investigate the effect of supersymmetric CP violating phases on the inclusive decay B\to X_d\gamma. Although such a decay contains a large background from B\to X_s\gamma, if isolated it may exhibit sizeable CP violation, both in the Standard Model (SM) and in the context of models beyond the SM. With unconstrained supersymmetric CP violating phases we show that the direct CP asymmetry (A_CP) lies in the region -40% \le A_CP \le 40%, where a positive asymmetry would constitute a clear signal of physics beyond the SM. Even if a direct measurement of B\to X_d\gamma proves too dif ficult experimentally, its asymmetry contributes non-negligibly to the measurements of A_CP for B\to X_s\gamma, and thus should be included in future analyses. We show t hat there may be both constructive and destructive interference between A^d\gamma_CP and A^s\gamma_CP.
1508.07811
Francesco Hautmann
F. Hautmann, H. Jung, H. Van Haevermaet
Treating jet correlations in high pile-up at hadron colliders
Latex. 8 pages, 5 figures
null
10.1016/j.physletb.2015.12.079
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Experiments in the high-luminosity runs at the Large Hadron Collider face the challenges of very large pile-up. Primary techniques to deal with this are based on precise vertex and track reconstruction. Outside tracker acceptances, however, lie regions of interest for many aspects of the LHC physics program. We explore complementary approaches to pile-up treatment and propose a data-driven jet-mixing method which can be used outside tracker acceptances without depending on Monte Carlo generators. The method can be applied to treat correlation observables and take into account, besides the jet transverse momentum pedestal, effects of hard jets from pile-up.
[ { "created": "Mon, 31 Aug 2015 13:09:59 GMT", "version": "v1" } ]
2016-02-17
[ [ "Hautmann", "F.", "" ], [ "Jung", "H.", "" ], [ "Van Haevermaet", "H.", "" ] ]
Experiments in the high-luminosity runs at the Large Hadron Collider face the challenges of very large pile-up. Primary techniques to deal with this are based on precise vertex and track reconstruction. Outside tracker acceptances, however, lie regions of interest for many aspects of the LHC physics program. We explore complementary approaches to pile-up treatment and propose a data-driven jet-mixing method which can be used outside tracker acceptances without depending on Monte Carlo generators. The method can be applied to treat correlation observables and take into account, besides the jet transverse momentum pedestal, effects of hard jets from pile-up.
1202.3611
Jacques Soffer
Claude Bourrely, John M. Myers, Jacques Soffer, Tai Tsun Wu
High-energy asymptotic behavior of the Bourrely-Soffer-Wu model for elastic scattering
27 pages, 11 figures,revised version to appear in Physical Review D
null
10.1103/PhysRevD.85.096009
CERN-PH-TH/2012-033
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Some time ago, an accurate phenomenological approach, the BSW model, was developed for proton-proton and antiproton-proton elastic scattering cross sections at center-of-mass energies above 10 GeV. This model has been used to give successful theoretical predictions for these processes, at successive collider energies. The BSW model involves a combination of integrals that, while computable numerically at fairly high energies, require some mathematical analysis to reveal the high-energy asymptotic behavior. In this paper we present a high-energy asymptotic representation of the scattering amplitude at moderate momentum transfer, for the leading order in an expansion parameter closely related to the logarithm of the center-of-mass energy. The fact that the expansion parameter goes as the logarithm of the energy means that the asymptotic behavior is accurate only for energies greatly beyond any foreseeable experiment. However, we compare the asymptotic representation against the numerically calculated model for energies in a less extreme region of energy. The asymptotic representation is given by a simple formula which, in particular, exhibits the oscillations of the differential cross section with momentum transfer. We also compare the BSW asymptotic behavior with the Singh-Roy unitarity upper bound for the diffraction peak.
[ { "created": "Thu, 16 Feb 2012 15:04:57 GMT", "version": "v1" }, { "created": "Tue, 8 May 2012 20:46:20 GMT", "version": "v2" } ]
2015-06-04
[ [ "Bourrely", "Claude", "" ], [ "Myers", "John M.", "" ], [ "Soffer", "Jacques", "" ], [ "Wu", "Tai Tsun", "" ] ]
Some time ago, an accurate phenomenological approach, the BSW model, was developed for proton-proton and antiproton-proton elastic scattering cross sections at center-of-mass energies above 10 GeV. This model has been used to give successful theoretical predictions for these processes, at successive collider energies. The BSW model involves a combination of integrals that, while computable numerically at fairly high energies, require some mathematical analysis to reveal the high-energy asymptotic behavior. In this paper we present a high-energy asymptotic representation of the scattering amplitude at moderate momentum transfer, for the leading order in an expansion parameter closely related to the logarithm of the center-of-mass energy. The fact that the expansion parameter goes as the logarithm of the energy means that the asymptotic behavior is accurate only for energies greatly beyond any foreseeable experiment. However, we compare the asymptotic representation against the numerically calculated model for energies in a less extreme region of energy. The asymptotic representation is given by a simple formula which, in particular, exhibits the oscillations of the differential cross section with momentum transfer. We also compare the BSW asymptotic behavior with the Singh-Roy unitarity upper bound for the diffraction peak.
1411.2150
Maxim Khlopov
Maxim Yu. Khlopov
Introduction to the special issue of Modern Physics Letters A "Indirect dark matter searches"
9 pages. arXiv admin note: text overlap with arXiv:1311.2468, arXiv:1402.0181, arXiv:0801.0116
Mod. Phys. Lett. A, Vol. 29, No. 37(2014) 1402001
10.1142/S0217732314020015
null
hep-ph astro-ph.CO astro-ph.HE gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The nature of cosmological dark matter finds its explanation in physics beyond the Standard model of elementary particles. The landscape of dark matter candidates contains a wide variety of species, either elusive or hardly detectable in direct experimental searches. Even in case, when such searches are possible the interpretation of their results implies additional sources of information, which provide indirect effects of dark matter. Some nontrivial probes for the nature of the dark matter are presented in the present issue.
[ { "created": "Sat, 8 Nov 2014 18:35:37 GMT", "version": "v1" } ]
2014-12-01
[ [ "Khlopov", "Maxim Yu.", "" ] ]
The nature of cosmological dark matter finds its explanation in physics beyond the Standard model of elementary particles. The landscape of dark matter candidates contains a wide variety of species, either elusive or hardly detectable in direct experimental searches. Even in case, when such searches are possible the interpretation of their results implies additional sources of information, which provide indirect effects of dark matter. Some nontrivial probes for the nature of the dark matter are presented in the present issue.
hep-ph/0204277
Urs Wiedemann
Alex Kovner, Urs Achim Wiedemann
Perturbative Saturation and the Soft Pomeron
27 pages, Latex, 5 eps-figures
Phys.Rev. D66 (2002) 034031
10.1103/PhysRevD.66.034031
CERN-TH-2002-089
hep-ph
null
We show that perturbation theory provides two distinct mechanisms for the power like growth of hadronic cross sections at high energy. One, the leading BFKL effect is due to the growth of the parton density, and is characterized by the leading BFKL exponent. The other mechanism is due to the infrared diffusion, or the long range nature of the Coulomb field of perturbatively massless gluons. When perturbative saturation effects are taken into account, the first mechanism is rendered ineffective but the second one persists. We suggest that these two distinct mechanisms are responsible for the appearance of two pomerons. The density growth effects are responsible for the hard pomeron and manifest themselves in small systems (e.g. gamma^* or small size fluctuations in the proton wave function) where saturation effects are not important. The soft pomeron is the manifestation of the exponential growth of the black saturated regions which appear in typical hadronic systems. We point out that the nonlinear generalization of the BFKL equation which takes into account wave function saturation effects ("pomeron loops") provides a well defined perturbative framework for the calculation of the soft pomeron intercept. The conjecture of a perturbative soft pomeron is consistent with picturing the proton as a loosely bound system of several small black regions corresponding e.g. to constituent quarks of size about 0.3 fm. Phenomenological implications of this picture are compatible with the main qualitative features of data on p-p scattering.
[ { "created": "Wed, 24 Apr 2002 07:45:13 GMT", "version": "v1" } ]
2009-11-07
[ [ "Kovner", "Alex", "" ], [ "Wiedemann", "Urs Achim", "" ] ]
We show that perturbation theory provides two distinct mechanisms for the power like growth of hadronic cross sections at high energy. One, the leading BFKL effect is due to the growth of the parton density, and is characterized by the leading BFKL exponent. The other mechanism is due to the infrared diffusion, or the long range nature of the Coulomb field of perturbatively massless gluons. When perturbative saturation effects are taken into account, the first mechanism is rendered ineffective but the second one persists. We suggest that these two distinct mechanisms are responsible for the appearance of two pomerons. The density growth effects are responsible for the hard pomeron and manifest themselves in small systems (e.g. gamma^* or small size fluctuations in the proton wave function) where saturation effects are not important. The soft pomeron is the manifestation of the exponential growth of the black saturated regions which appear in typical hadronic systems. We point out that the nonlinear generalization of the BFKL equation which takes into account wave function saturation effects ("pomeron loops") provides a well defined perturbative framework for the calculation of the soft pomeron intercept. The conjecture of a perturbative soft pomeron is consistent with picturing the proton as a loosely bound system of several small black regions corresponding e.g. to constituent quarks of size about 0.3 fm. Phenomenological implications of this picture are compatible with the main qualitative features of data on p-p scattering.
2107.01053
James Keaveney M
James Keaveney
Constraining the SMEFT with a differential cross section measurement of $tWZ$ production at the HL-LHC
9 pages, 3 figures
Phys. Rev. D 107, 036021 (2023)
10.1103/PhysRevD.107.036021
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
A prospective measurement of the differential cross section of \tWZ production with respect to the transverse momentum of the \PZ boson using a general-purpose detector at the High-Luminosity Large Hadron Collider (HL-LHC) is described. The response of a general-purpose detector at the HL-LHC is simulated and used to estimate the uncertainties and covariances of the differential cross section measurement. Constraints on the Standard Model Effective Field Theory (SMEFT) enabled by the measurement are estimated. A parametric model of the differential cross section in the SMEFT is constructed and is used to determine the expected posterior probability function of six SMEFT Wilson coefficients and the expected 95\% Bayesian credible intervals for each coefficient and pair of coefficients. The intervals suggest that for all coefficients, the measurement will provide competitive but weaker constraints than those derived from other \mbox{HL-LHC} measurements involving top quarks and \PZ bosons. However, as the measurement is simultaneously sensitive to to a unique set of SMEFT coefficients, it will provide a useful input to a global SMEFT analysis that considers many operators.
[ { "created": "Fri, 2 Jul 2021 13:03:32 GMT", "version": "v1" }, { "created": "Mon, 25 Oct 2021 09:45:28 GMT", "version": "v2" }, { "created": "Wed, 7 Jun 2023 14:51:50 GMT", "version": "v3" } ]
2023-06-14
[ [ "Keaveney", "James", "" ] ]
A prospective measurement of the differential cross section of \tWZ production with respect to the transverse momentum of the \PZ boson using a general-purpose detector at the High-Luminosity Large Hadron Collider (HL-LHC) is described. The response of a general-purpose detector at the HL-LHC is simulated and used to estimate the uncertainties and covariances of the differential cross section measurement. Constraints on the Standard Model Effective Field Theory (SMEFT) enabled by the measurement are estimated. A parametric model of the differential cross section in the SMEFT is constructed and is used to determine the expected posterior probability function of six SMEFT Wilson coefficients and the expected 95\% Bayesian credible intervals for each coefficient and pair of coefficients. The intervals suggest that for all coefficients, the measurement will provide competitive but weaker constraints than those derived from other \mbox{HL-LHC} measurements involving top quarks and \PZ bosons. However, as the measurement is simultaneously sensitive to to a unique set of SMEFT coefficients, it will provide a useful input to a global SMEFT analysis that considers many operators.
hep-ph/9907502
Ralf Rapp
R. Rapp and J. Wambach
Low-Mass Dileptons at the CERN-SpS: Evidence for Chiral Restoration?
6 pages ReVTeX including 5 eps-figures
Eur.Phys.J.A6:415-420,1999
10.1007/s100500050364
SUNY-NTG-99-25
hep-ph nucl-th
null
Using a rather complete description of the in-medium $\rho$ spectral function - being constrained by various independent experimental information - we calculate pertinent dilepton production rates from hot and dense hadronic matter. The strong broadening of the $\rho$ resonance entails a reminiscence to perturbative $q\bar q$ annihilation rates in the vicinity of the phase boundary. The application to dilepton observables in Pb(158AGeV)+Au collisions - incorporating recent information on the hadro-chemical composition at CERN-SpS energies - essentially supports the broadening scenario. Possible implications for the nature of chiral symmetry restoration are outlined.
[ { "created": "Mon, 26 Jul 1999 18:39:56 GMT", "version": "v1" } ]
2010-04-06
[ [ "Rapp", "R.", "" ], [ "Wambach", "J.", "" ] ]
Using a rather complete description of the in-medium $\rho$ spectral function - being constrained by various independent experimental information - we calculate pertinent dilepton production rates from hot and dense hadronic matter. The strong broadening of the $\rho$ resonance entails a reminiscence to perturbative $q\bar q$ annihilation rates in the vicinity of the phase boundary. The application to dilepton observables in Pb(158AGeV)+Au collisions - incorporating recent information on the hadro-chemical composition at CERN-SpS energies - essentially supports the broadening scenario. Possible implications for the nature of chiral symmetry restoration are outlined.
1007.4005
Matthias Neubert
Thomas Becher and Matthias Neubert
Drell-Yan production at small q_T, transverse parton distributions and the collinear anomaly
32 pages, 2 figures; version to appear in Eur. Phys. J. C
Eur.Phys.J.C71:1665,2011
10.1140/epjc/s10052-011-1665-7
HD-THEP/10-13, MZ-TH/10-26
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using methods from effective field theory, an exact all-order expression for the Drell-Yan cross section at small transverse momentum is derived directly in q_T space, in which all large logarithms are resummed. The anomalous dimensions and matching coefficients necessary for resummation at NNLL order are given explicitly. The precise relation between our result and the Collins-Soper-Sterman formula is discussed, and as a by-product the previously unknown three-loop coefficient A^(3) is obtained. The naive factorization of the cross section at small transverse momentum is broken by a collinear anomaly, which prevents a process-independent definition of x_T-dependent parton distribution functions. A factorization theorem is derived for the product of two such functions, in which the dependence on the hard momentum transfer is separated out. The remainder factors into a product of two functions of longitudinal momentum variables and x_T^2, whose renormalization-group evolution is derived and solved in closed form. The matching of these functions at small x_T onto standard parton distributions is calculated at O(alpha_s), while their anomalous dimensions are known to three loops.
[ { "created": "Thu, 22 Jul 2010 20:42:22 GMT", "version": "v1" }, { "created": "Wed, 29 Sep 2010 17:35:35 GMT", "version": "v2" }, { "created": "Mon, 6 Jun 2011 23:46:05 GMT", "version": "v3" } ]
2011-06-20
[ [ "Becher", "Thomas", "" ], [ "Neubert", "Matthias", "" ] ]
Using methods from effective field theory, an exact all-order expression for the Drell-Yan cross section at small transverse momentum is derived directly in q_T space, in which all large logarithms are resummed. The anomalous dimensions and matching coefficients necessary for resummation at NNLL order are given explicitly. The precise relation between our result and the Collins-Soper-Sterman formula is discussed, and as a by-product the previously unknown three-loop coefficient A^(3) is obtained. The naive factorization of the cross section at small transverse momentum is broken by a collinear anomaly, which prevents a process-independent definition of x_T-dependent parton distribution functions. A factorization theorem is derived for the product of two such functions, in which the dependence on the hard momentum transfer is separated out. The remainder factors into a product of two functions of longitudinal momentum variables and x_T^2, whose renormalization-group evolution is derived and solved in closed form. The matching of these functions at small x_T onto standard parton distributions is calculated at O(alpha_s), while their anomalous dimensions are known to three loops.
1408.1114
Aleksander Kusina
A. Kusina, K. Kovarik, T. Jezo, D. B. Clark, F. I. Olness, I. Schienbein, J. Y. Yu
Update on nCTEQ PDFs: nuclear PDF uncertainties and LHC applications
Presented at DIS2014, 28 April - 2 May 2014, Warsaw, Poland. PoS(DIS2014)047
PoS (DIS2014) 047
null
SMU-HEP-14-03
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present updated nCTEQ nuclear parton distribution functions with errors including pion production data from RHIC. We compare them with the results of other groups and present selected LHC applications.
[ { "created": "Tue, 5 Aug 2014 21:09:41 GMT", "version": "v1" } ]
2014-10-24
[ [ "Kusina", "A.", "" ], [ "Kovarik", "K.", "" ], [ "Jezo", "T.", "" ], [ "Clark", "D. B.", "" ], [ "Olness", "F. I.", "" ], [ "Schienbein", "I.", "" ], [ "Yu", "J. Y.", "" ] ]
We present updated nCTEQ nuclear parton distribution functions with errors including pion production data from RHIC. We compare them with the results of other groups and present selected LHC applications.
1608.01610
Masahiro Ibe
Masahiro Ibe, Tsutomu T. Yanagida
Lower limit on the gravitino mass in low-scale gauge mediation with $m_H\simeq 125$GeV
13 pages, 1 figure
null
10.1016/j.physletb.2016.11.016
IPMU16-0116
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit low-scale gauge mediation models in light of recent observations of CMB Lensing and Cosmic Shear which put a severe upper limit on the gravitino mass, $m_{3/2} \lesssim 4.7$eV. With such a stringent constraint, many models of low-scale gauge mediation are excluded when the squark masses are required to be rather large to explain the observed Higgs boson mass. In this note, we discuss a type of low-scale gauge mediation models which satisfy both the observed Higgs boson mass and the upper limit on the gravitino mass. We also show that the gravitino mass cannot be smaller than about 1eV even in such models, which may be tested in future observations of 21 cm line fluctuations.
[ { "created": "Thu, 4 Aug 2016 16:53:29 GMT", "version": "v1" } ]
2016-11-16
[ [ "Ibe", "Masahiro", "" ], [ "Yanagida", "Tsutomu T.", "" ] ]
We revisit low-scale gauge mediation models in light of recent observations of CMB Lensing and Cosmic Shear which put a severe upper limit on the gravitino mass, $m_{3/2} \lesssim 4.7$eV. With such a stringent constraint, many models of low-scale gauge mediation are excluded when the squark masses are required to be rather large to explain the observed Higgs boson mass. In this note, we discuss a type of low-scale gauge mediation models which satisfy both the observed Higgs boson mass and the upper limit on the gravitino mass. We also show that the gravitino mass cannot be smaller than about 1eV even in such models, which may be tested in future observations of 21 cm line fluctuations.
hep-ph/0212038
D. Indumathi
D. Indumathi (Inst. Mathematical Sciences, Chennai)
Implications on neutrino oscillation plus decay from recent solar neutrino data
18 pages Latex file, with 3 epsf figures; some references added
null
null
IMSc/2002/11/38
hep-ph
null
Recently the Sudbury Neutrino Observatory (SNO) has measured both the rates as well as the day-night asymmetries in the flux of neutrinos from the Sun in the charged-current (CC), neutral-current (NC) and elastic scattering (ES) channels. Motivated by the small but negative day-night asymmetry in the NC channel at SNO (1.2 standard deviations away from zero), we consider whether such a non-zero asymmetry can be generated in a framework where active neutrinos can both oscillate and decay, since the NC day-night asymmetry is zero in a frame-work that includes pure oscillations of active flavours. We find that the neutral current day-night asymmetry is strictly zero when we include both oscillations and decay. The result holds for arbitrary number of active neutrino species, with some reasonable assumptions on the decay parameters. Hence, a non-zero asymmetry in the neutral current sector, if it survives, can only come from oscillations/decay into sterile flavours. We also examine the allowed region of parameter space coming from a combined analysis of the total event rates in the charged-current, neutral current and elastic scattering sectors in a two-flavour framework, and find that the neutral current rates are most sensitive to (and hence restrict considerably) the allowed values of the decay parameter involving the life-time of the heavier mass eigenstate to $\tau_{2_0} > 10^{-4}$ s for eV mass neutrinos.
[ { "created": "Tue, 3 Dec 2002 09:31:46 GMT", "version": "v1" }, { "created": "Mon, 9 Dec 2002 12:38:47 GMT", "version": "v2" } ]
2007-05-23
[ [ "Indumathi", "D.", "", "Inst. Mathematical Sciences, Chennai" ] ]
Recently the Sudbury Neutrino Observatory (SNO) has measured both the rates as well as the day-night asymmetries in the flux of neutrinos from the Sun in the charged-current (CC), neutral-current (NC) and elastic scattering (ES) channels. Motivated by the small but negative day-night asymmetry in the NC channel at SNO (1.2 standard deviations away from zero), we consider whether such a non-zero asymmetry can be generated in a framework where active neutrinos can both oscillate and decay, since the NC day-night asymmetry is zero in a frame-work that includes pure oscillations of active flavours. We find that the neutral current day-night asymmetry is strictly zero when we include both oscillations and decay. The result holds for arbitrary number of active neutrino species, with some reasonable assumptions on the decay parameters. Hence, a non-zero asymmetry in the neutral current sector, if it survives, can only come from oscillations/decay into sterile flavours. We also examine the allowed region of parameter space coming from a combined analysis of the total event rates in the charged-current, neutral current and elastic scattering sectors in a two-flavour framework, and find that the neutral current rates are most sensitive to (and hence restrict considerably) the allowed values of the decay parameter involving the life-time of the heavier mass eigenstate to $\tau_{2_0} > 10^{-4}$ s for eV mass neutrinos.
1804.02728
Francesco Giacosa
Francesco Giacosa
QFT derivation of the decay law of an unstable particle with nonzero momentum
10 pages
null
null
null
hep-ph hep-th quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a quantum field theoretical derivation of the nondecay probability of an unstable particle with nonzero three-momentum $\mathbf{p}$. To this end, we use the (fully resummed) propagator of the unstable particle, denoted as $S,$ to obtain the energy probability distribution, called $d_{S}^{\mathbf{p} }(E)$, as the imaginary part of the propagator. The nondecay probability amplitude of the particle $S$ with momentum $\mathbf{p}$ turns out to be, as usual, its Fourier transform: $a_{S}^{\mathbf{p}}(t)=\int_{\sqrt{m_{th} ^{2}+\mathbf{p}^{2}}}^{\infty}dEd_{S}^{\mathbf{p}}(E)e^{-iEt}$ ($m_{th}$ is the lowest energy threshold in the energy frame, corresponding to the sum of masses of the decay products). Upon a variable transformation, one can rewrite it as $a_{S}^{\mathbf{p}}(t)=\int_{m_{th}}^{\infty}dmd_{S} ^{\mathbf{0}}(m)e^{-i\sqrt{m_{th}^{2}+\mathbf{p}^{2}}t}$ [here, $d_{S} ^{\mathbf{0}}(m)\equiv d_{S}(m)$ is the usual spectral function (or mass distribution) in the rest frame]. Hence, the latter expression, previously obtained by different approaches, is here confirmed in an independent and, most importantly, covariant QFT-based approach. Its consequences are not yet fully explored but appear to be quite surprising (such as the fact that usual time-dilatation formula does not apply), thus its firm understanding and investigation can be a fruitful subject of future research.
[ { "created": "Sun, 8 Apr 2018 17:43:50 GMT", "version": "v1" } ]
2018-04-10
[ [ "Giacosa", "Francesco", "" ] ]
We present a quantum field theoretical derivation of the nondecay probability of an unstable particle with nonzero three-momentum $\mathbf{p}$. To this end, we use the (fully resummed) propagator of the unstable particle, denoted as $S,$ to obtain the energy probability distribution, called $d_{S}^{\mathbf{p} }(E)$, as the imaginary part of the propagator. The nondecay probability amplitude of the particle $S$ with momentum $\mathbf{p}$ turns out to be, as usual, its Fourier transform: $a_{S}^{\mathbf{p}}(t)=\int_{\sqrt{m_{th} ^{2}+\mathbf{p}^{2}}}^{\infty}dEd_{S}^{\mathbf{p}}(E)e^{-iEt}$ ($m_{th}$ is the lowest energy threshold in the energy frame, corresponding to the sum of masses of the decay products). Upon a variable transformation, one can rewrite it as $a_{S}^{\mathbf{p}}(t)=\int_{m_{th}}^{\infty}dmd_{S} ^{\mathbf{0}}(m)e^{-i\sqrt{m_{th}^{2}+\mathbf{p}^{2}}t}$ [here, $d_{S} ^{\mathbf{0}}(m)\equiv d_{S}(m)$ is the usual spectral function (or mass distribution) in the rest frame]. Hence, the latter expression, previously obtained by different approaches, is here confirmed in an independent and, most importantly, covariant QFT-based approach. Its consequences are not yet fully explored but appear to be quite surprising (such as the fact that usual time-dilatation formula does not apply), thus its firm understanding and investigation can be a fruitful subject of future research.
1801.06145
Xin Liu
Xin Liu, Hsiang-nan Li, Zhen-Jun Xiao
Improved perturbative QCD formalism for $B_c$ meson decays
9 pages, 4 figures, and 1 table, references added
Phys. Rev. D 97, 113001 (2018)
10.1103/PhysRevD.97.113001
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive the $k_T$ resummation for doubly heavy-flavored $B_c$ meson decays by including the charm quark mass effect into the known formula for a heavy-light system. The resultant Sudakov factor is employed in the perutrbative QCD study of the "golden channel" $B_c^+ \to J/\psi \pi^+$. With a reasonable model for the $B_c$ meson distribution amplitude, which maintains approximate on-shell conditions of both the partonic bottom and charm quarks, it is observed that the imaginary piece of the $B_c \to J/\psi$ transition form factor appears to be power suppressed, and the $B_c^+ \to J/\psi \pi^+$ branching ratio is not lower than $10^{-3}$. The above improved perutrbative QCD formalism is applicable to $B_c$ meson decays to other charmonia and charmed mesons.
[ { "created": "Thu, 18 Jan 2018 17:50:35 GMT", "version": "v1" }, { "created": "Sat, 2 Jun 2018 07:14:57 GMT", "version": "v2" }, { "created": "Wed, 31 Oct 2018 08:37:22 GMT", "version": "v3" } ]
2018-11-01
[ [ "Liu", "Xin", "" ], [ "Li", "Hsiang-nan", "" ], [ "Xiao", "Zhen-Jun", "" ] ]
We derive the $k_T$ resummation for doubly heavy-flavored $B_c$ meson decays by including the charm quark mass effect into the known formula for a heavy-light system. The resultant Sudakov factor is employed in the perutrbative QCD study of the "golden channel" $B_c^+ \to J/\psi \pi^+$. With a reasonable model for the $B_c$ meson distribution amplitude, which maintains approximate on-shell conditions of both the partonic bottom and charm quarks, it is observed that the imaginary piece of the $B_c \to J/\psi$ transition form factor appears to be power suppressed, and the $B_c^+ \to J/\psi \pi^+$ branching ratio is not lower than $10^{-3}$. The above improved perutrbative QCD formalism is applicable to $B_c$ meson decays to other charmonia and charmed mesons.
hep-ph/0307307
S. Arunagiri
S. Arunagiri and C. Q. Geng (National Tsing Hua University, Taiwan)
T-violating triple product asymmetries in Lambda_b --> Lambda pi pi decay
6 pages; an equation inserted and a reference added; typos corrected. Version to appear in PRD
Phys.Rev. D69 (2004) 017901
10.1103/PhysRevD.69.017901
null
hep-ph
null
We study Lambda_b --> Lambda pi pi. The branching fraction is predicted to be about 4.38 x 10^{-6}%. Within the standard model, we compute T-odd triple product asymmetries to be about 1.4, 4.3, 6.5 and 7.2% respectively due to s_{Lambda_b}(s_Lambda) . (p_Lambda x p_pi) and p_Lambda (p_pi) . (s_Lambda x s_{Lambda_b}).
[ { "created": "Fri, 25 Jul 2003 01:40:12 GMT", "version": "v1" }, { "created": "Tue, 12 Aug 2003 11:45:29 GMT", "version": "v2" }, { "created": "Thu, 30 Oct 2003 12:09:51 GMT", "version": "v3" } ]
2009-11-10
[ [ "Arunagiri", "S.", "", "National Tsing Hua University, Taiwan" ], [ "Geng", "C. Q.", "", "National Tsing Hua University, Taiwan" ] ]
We study Lambda_b --> Lambda pi pi. The branching fraction is predicted to be about 4.38 x 10^{-6}%. Within the standard model, we compute T-odd triple product asymmetries to be about 1.4, 4.3, 6.5 and 7.2% respectively due to s_{Lambda_b}(s_Lambda) . (p_Lambda x p_pi) and p_Lambda (p_pi) . (s_Lambda x s_{Lambda_b}).
hep-ph/9708489
Massimo Pietroni
Denis Comelli, Massimo Pietroni
Screening Masses in SU(N) from Wilson Renormalization Group
10 pages, LaTex + 3 figures, requires epsfig
Phys.Lett. B417 (1998) 337-342
10.1016/S0370-2693(97)01372-5
DFPD 97/TH/37
hep-ph
null
We apply a gauge invariant formulation of Wilson Renormalization Group (RG) to the computation of the Debye and transverse gluon masses in pure gauge SU(N) at high temperature. Following the Hard Thermal Loop effective field theory as a guideline, we develop an approximation scheme to the exact evolution equations. The Debye mass receives sizable corrections compared to the leading order perturbative result, mainly due to the infrared singular behavior in the transverse gluon sector. A non-vanishing mass for the transverse gluons is found, which acts as an infrared regulator though not efficiently enough as to restore the validity of perturbation theory. Indeed, discussing the role of higher dimensional operators, we show that the gauge coupling for the transverse modes typically flows to non-perturbative values unless extremely high temperatures are reached. After comparing our results with recent lattice simulations, we comment on the possibility of using this formulation of the RG as a tool to construct an effective field theory for the non-perturbative, long wavelength, transverse modes.
[ { "created": "Fri, 29 Aug 1997 10:25:08 GMT", "version": "v1" } ]
2009-10-30
[ [ "Comelli", "Denis", "" ], [ "Pietroni", "Massimo", "" ] ]
We apply a gauge invariant formulation of Wilson Renormalization Group (RG) to the computation of the Debye and transverse gluon masses in pure gauge SU(N) at high temperature. Following the Hard Thermal Loop effective field theory as a guideline, we develop an approximation scheme to the exact evolution equations. The Debye mass receives sizable corrections compared to the leading order perturbative result, mainly due to the infrared singular behavior in the transverse gluon sector. A non-vanishing mass for the transverse gluons is found, which acts as an infrared regulator though not efficiently enough as to restore the validity of perturbation theory. Indeed, discussing the role of higher dimensional operators, we show that the gauge coupling for the transverse modes typically flows to non-perturbative values unless extremely high temperatures are reached. After comparing our results with recent lattice simulations, we comment on the possibility of using this formulation of the RG as a tool to construct an effective field theory for the non-perturbative, long wavelength, transverse modes.
hep-ph/0006087
Egor Babave
Egor Babaev
Nonlinear sigma model approach for chiral fluctuations and symmetry breakdown in Nambu-Jona-Lasinio model
accepted to Phys. Rev. D. Latest updates of this and related papers are available at http://www.teorfys.uu.se/PEOPLE/egor/
Phys.Rev. D62 (2000) 074020
10.1103/PhysRevD.62.074020
null
hep-ph cond-mat hep-th
null
In this paper we discuss symmetry breakdown in NJL model at low N_c. In particular we propose a modified NJL model that displays a symmetry breakdown and also at finite temperatures under certain conditions the chiral fluctuations in this model give rise to a phase analogous to pseudogap phase of strong-coupling and low carrier density superconductors.
[ { "created": "Fri, 9 Jun 2000 22:09:22 GMT", "version": "v1" } ]
2009-10-31
[ [ "Babaev", "Egor", "" ] ]
In this paper we discuss symmetry breakdown in NJL model at low N_c. In particular we propose a modified NJL model that displays a symmetry breakdown and also at finite temperatures under certain conditions the chiral fluctuations in this model give rise to a phase analogous to pseudogap phase of strong-coupling and low carrier density superconductors.
1010.4356
Alfredo Vega Dr.
Alfredo Vega and Ivan Schmidt
Considering anomalous dimensions in AdS/QCD models
Talk given at Light Cone 2010: Relativistic Hadronic and Particle Physics, June 14-18, 2010, Valencia, Spain
PoS LC2010:031,2010
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss an AdS / QCD model that consider anomalous dimensions. The effect of this kind of dimensions is considered as a mass term that depend on holographical coordenate for duals modes in bulk.
[ { "created": "Thu, 21 Oct 2010 03:09:07 GMT", "version": "v1" } ]
2011-03-10
[ [ "Vega", "Alfredo", "" ], [ "Schmidt", "Ivan", "" ] ]
We discuss an AdS / QCD model that consider anomalous dimensions. The effect of this kind of dimensions is considered as a mass term that depend on holographical coordenate for duals modes in bulk.
2303.08869
Taegyun Kim
Taegyun Kim, Jeong Han Kim, Soubhik Kumar, Adam Martin, Moritz M\"unchmeyer, Yuhsin Tsai
Probing Cosmological Particle Production and Pairwise Hotspots with Deep Neural Networks
null
null
null
null
hep-ph astro-ph.CO
http://creativecommons.org/publicdomain/zero/1.0/
Particles with masses much larger than the inflationary Hubble scale, $H_I$, can be pair-produced non-adiabatically during inflation. Due to their large masses, the produced particles modify the curvature perturbation around their locations. These localized perturbations eventually give rise to localized signatures on the Cosmic Microwave Background (CMB), in particular, pairwise hotspots (PHS). In this work, we show that Convolutional Neural Networks (CNN) provide a powerful tool for identifying PHS on the CMB. While for a given hotspot profile a traditional Matched Filter Analysis is known to be optimal, a Neural Network learns to effectively detect the large variety of shapes that can arise in realistic models of particle production. Considering an idealized situation where the dominant background to the PHS signal comes from the standard CMB fluctuations, we show that a CNN can isolate the PHS with $\mathcal{O}(10)\%$ efficiency even if the hotspot temperature is $\mathcal{O}(10)$ times smaller than the average CMB fluctuations. Overall, the CNN search is sensitive to heavy particle masses $M_0/H_I=\mathcal{O}(200)$, and constitutes one of the unique probes of very high energy particle physics.
[ { "created": "Wed, 15 Mar 2023 18:34:28 GMT", "version": "v1" } ]
2023-03-17
[ [ "Kim", "Taegyun", "" ], [ "Kim", "Jeong Han", "" ], [ "Kumar", "Soubhik", "" ], [ "Martin", "Adam", "" ], [ "Münchmeyer", "Moritz", "" ], [ "Tsai", "Yuhsin", "" ] ]
Particles with masses much larger than the inflationary Hubble scale, $H_I$, can be pair-produced non-adiabatically during inflation. Due to their large masses, the produced particles modify the curvature perturbation around their locations. These localized perturbations eventually give rise to localized signatures on the Cosmic Microwave Background (CMB), in particular, pairwise hotspots (PHS). In this work, we show that Convolutional Neural Networks (CNN) provide a powerful tool for identifying PHS on the CMB. While for a given hotspot profile a traditional Matched Filter Analysis is known to be optimal, a Neural Network learns to effectively detect the large variety of shapes that can arise in realistic models of particle production. Considering an idealized situation where the dominant background to the PHS signal comes from the standard CMB fluctuations, we show that a CNN can isolate the PHS with $\mathcal{O}(10)\%$ efficiency even if the hotspot temperature is $\mathcal{O}(10)$ times smaller than the average CMB fluctuations. Overall, the CNN search is sensitive to heavy particle masses $M_0/H_I=\mathcal{O}(200)$, and constitutes one of the unique probes of very high energy particle physics.
2004.11466
Yu. A. Simonov
Yu.A. Simonov
Hadron Form Factors with the Boost-Corrected Wave Functions
v2: 15 pages, 4 tables
null
10.1134/S1063778821020150
null
hep-ph hep-ex hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Hadron form factors are calculated using the Lorentz contracted wave functions, determined in the arbitrary dynamical scheme with the instantaneous interaction. It is shown that the large $Q$ asymptotics of the form factors is defined by the contraction coefficient $C_m(Q^2) = \frac{m}{\sqrt(m^2+ Q^2/4)}$, where $m$ is the meson mass, and weakly depends on the interaction used. The resulting form factors $F_\pi$ and $F_K$ are obtained in good agreement with the lattice and experimental data. Important consequences for the dynamics of hadron decays and scattering are shortly discussed.
[ { "created": "Thu, 23 Apr 2020 21:23:31 GMT", "version": "v1" }, { "created": "Mon, 8 Jun 2020 15:36:42 GMT", "version": "v2" } ]
2021-05-19
[ [ "Simonov", "Yu. A.", "" ] ]
Hadron form factors are calculated using the Lorentz contracted wave functions, determined in the arbitrary dynamical scheme with the instantaneous interaction. It is shown that the large $Q$ asymptotics of the form factors is defined by the contraction coefficient $C_m(Q^2) = \frac{m}{\sqrt(m^2+ Q^2/4)}$, where $m$ is the meson mass, and weakly depends on the interaction used. The resulting form factors $F_\pi$ and $F_K$ are obtained in good agreement with the lattice and experimental data. Important consequences for the dynamics of hadron decays and scattering are shortly discussed.
hep-ph/9603301
Abel Steven
S.A.Abel
Singlets in Supersymmetry
23 pages, no figures, plain LaTeX, mistake in references corrected
null
null
ULB-TH-96/03
hep-ph
null
It is argued that singlet extensions of the MSSM at the weak scale are indicative of either gauged-$R$ symmetry or target space duality in a string effective action at the Planck scale. The criteria used are satisfactory primordial nucleosynthesis, absence of fine-tuning, and absence of cosmological problems such as domain walls. Models which have a global discrete symmetry such as the NMSSM may only be accommodated within rather complicated cosmological scenarios which are also discussed.
[ { "created": "Wed, 13 Mar 1996 16:03:08 GMT", "version": "v1" }, { "created": "Tue, 26 Mar 1996 11:37:02 GMT", "version": "v2" } ]
2008-02-03
[ [ "Abel", "S. A.", "" ] ]
It is argued that singlet extensions of the MSSM at the weak scale are indicative of either gauged-$R$ symmetry or target space duality in a string effective action at the Planck scale. The criteria used are satisfactory primordial nucleosynthesis, absence of fine-tuning, and absence of cosmological problems such as domain walls. Models which have a global discrete symmetry such as the NMSSM may only be accommodated within rather complicated cosmological scenarios which are also discussed.
hep-ph/9607324
Ed Stoeffhaas
O. J. P. Eboli, E. M. Gregores, and F. Halzen
Prompt Charmonium Production in Z Decays
Revtex, 12 pages, 2 postscript figures included using epsfig.sty Postscript version (Z-compressed) of complete paper also available at http://phenom.physics.wisc.edu/pub/preprints/1996/madph-96-950.ps.Z or at ftp://phenom.physics.wisc.edu/pub/preprints/1996/madph-96-950.ps.Z
Phys.Lett.B395:113-117,1997
10.1016/S0370-2693(97)00040-3
MADPH-96-950, IFUSP 1225
hep-ph
null
The color-evaporation model quantitatively describes all data on photoproduction and hadroproduction of charmonium. Although the model is in part nonperturbative, the associated parameters can for instance be determined from the charmonium photoproduction data. At this point its predictions for the prompt production of $\psi$'s at the $Z$ pole are made with no free parameters. We show here that this approach successfully describes all data on the production of prompt $\psi$'s in $Z$ decays.
[ { "created": "Mon, 15 Jul 1996 20:53:00 GMT", "version": "v1" } ]
2014-11-17
[ [ "Eboli", "O. J. P.", "" ], [ "Gregores", "E. M.", "" ], [ "Halzen", "F.", "" ] ]
The color-evaporation model quantitatively describes all data on photoproduction and hadroproduction of charmonium. Although the model is in part nonperturbative, the associated parameters can for instance be determined from the charmonium photoproduction data. At this point its predictions for the prompt production of $\psi$'s at the $Z$ pole are made with no free parameters. We show here that this approach successfully describes all data on the production of prompt $\psi$'s in $Z$ decays.
1904.06663
Priyanka Sarmah
Kumar Rao, Saurabh D. Rindani and Priyanka Sarmah
Probing anomalous gauge-Higgs couplings using $Z$ boson polarization at $e^+ e^-$ colliders
19 Pages, 9 Tables, added discussion and references; matches published version
Nucl. Phys.B (950),114840 (2020)
10.1016/j.nuclphysb.2019.114840
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study possible new physics interactions in the $ZZH$ vertex contributing to the Higgsstrahlung process $e^+ e^- \to ZH$ at proposed future $e^+e^-$ colliders using the polarization of the $Z$ as a probe. We calculate the spin density matrix of the $Z$ for the process and determine the eight independent polarization parameters of the $Z$ boson which have the potential to constrain the anomalous couplings. We study angular asymmetries using the decay leptons from the $Z$ boson which are simply related to the polarization observables. We also estimate the limits that can be placed on the anomalous couplings using measurements of these angular asymmetries at centre of mass energies of 250 GeV and 500 GeV and various combinations of polarized $e^+$ and $e^-$ beams.
[ { "created": "Sun, 14 Apr 2019 09:31:25 GMT", "version": "v1" }, { "created": "Fri, 20 Dec 2019 14:07:51 GMT", "version": "v2" } ]
2020-01-08
[ [ "Rao", "Kumar", "" ], [ "Rindani", "Saurabh D.", "" ], [ "Sarmah", "Priyanka", "" ] ]
We study possible new physics interactions in the $ZZH$ vertex contributing to the Higgsstrahlung process $e^+ e^- \to ZH$ at proposed future $e^+e^-$ colliders using the polarization of the $Z$ as a probe. We calculate the spin density matrix of the $Z$ for the process and determine the eight independent polarization parameters of the $Z$ boson which have the potential to constrain the anomalous couplings. We study angular asymmetries using the decay leptons from the $Z$ boson which are simply related to the polarization observables. We also estimate the limits that can be placed on the anomalous couplings using measurements of these angular asymmetries at centre of mass energies of 250 GeV and 500 GeV and various combinations of polarized $e^+$ and $e^-$ beams.
hep-ph/0305137
Krisztian Peters
Krisztian Peters, Gian Paolo Vacca
QCD Corrections to Electroweak Vector Boson Scattering at Small Scattering Angles
21 pages,9 figures, discussion on the helicity-flip impact factors added, typos corrected
Eur.Phys.J.C30:345-357,2003
10.1140/epjc/s2003-01281-6
null
hep-ph
null
We investigate the role of a certain class of QCD corrections to electroweak vector boson scattering at small scattering angles and large energies. These are present since, from the perturbative analysis, the vector bosons may dissociate into quark-antiquark pairs giving rise to colour dipoles interacting through gluon exchanges. After the computation of the vector boson impact factors, we present expressions for the lowest order QCD scattering amplitude and for the leading logarithmic BFKL amplitude. Particularly we discuss numerical results for the process $\gamma\gamma\to ZZ$. The QCD corrections to the cross section resulting from the interference with the electroweak ones are estimated and compared with the leading pure electroweak part. Corrections resulting from the leading log BFKL amplitude are of the order of few percent already at the $0.5 - 1$ TeV energy range.
[ { "created": "Tue, 13 May 2003 12:33:41 GMT", "version": "v1" }, { "created": "Thu, 26 Jun 2003 13:35:33 GMT", "version": "v2" } ]
2011-09-13
[ [ "Peters", "Krisztian", "" ], [ "Vacca", "Gian Paolo", "" ] ]
We investigate the role of a certain class of QCD corrections to electroweak vector boson scattering at small scattering angles and large energies. These are present since, from the perturbative analysis, the vector bosons may dissociate into quark-antiquark pairs giving rise to colour dipoles interacting through gluon exchanges. After the computation of the vector boson impact factors, we present expressions for the lowest order QCD scattering amplitude and for the leading logarithmic BFKL amplitude. Particularly we discuss numerical results for the process $\gamma\gamma\to ZZ$. The QCD corrections to the cross section resulting from the interference with the electroweak ones are estimated and compared with the leading pure electroweak part. Corrections resulting from the leading log BFKL amplitude are of the order of few percent already at the $0.5 - 1$ TeV energy range.
0805.4652
Gilad Perez
Gilad Perez and Lisa Randall
Natural Neutrino Masses and Mixings from Warped Geometry
18 pages, 3 figures, to match with published version
JHEP01(2009)077
10.1088/1126-6708/2009/01/077
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We demonstrate that flavor symmetries in warped geometry can provide a natural explanation for large mixing angles and economically explain the distinction between the quark and lepton flavor sectors. We show how to naturally generate Majorana neutrino masses assuming a gauged a U(1)_{B-L} symmetry broken in the UV that generates see-saw masses of the right size. This model requires lepton minimal flavor violation (LMFV) in which only Yukawa matrices (present on the IR brane) break the flavor symmetries. The symmetry-breaking is transmitted to charged lepton bulk mass parameters as well to generate the hierarchy of charged lepton masses. With LMFV, a GIM-like mechanism prevents dangerous flavor-changing processes for charged leptons and permits flavor-changing processes only in the presence of the neutrino Yukawa interaction and are therefore suppressed when the overall scale for the neutrino Yukawa matrix is slightly smaller than one in units of the curvature. In this case the theory can be consistent with a cutoff of 10 TeV and 3 TeV Kaluza-Klein masses.
[ { "created": "Fri, 30 May 2008 17:26:39 GMT", "version": "v1" }, { "created": "Fri, 24 Oct 2008 13:10:18 GMT", "version": "v2" }, { "created": "Wed, 28 Jan 2009 14:58:34 GMT", "version": "v3" } ]
2009-11-13
[ [ "Perez", "Gilad", "" ], [ "Randall", "Lisa", "" ] ]
We demonstrate that flavor symmetries in warped geometry can provide a natural explanation for large mixing angles and economically explain the distinction between the quark and lepton flavor sectors. We show how to naturally generate Majorana neutrino masses assuming a gauged a U(1)_{B-L} symmetry broken in the UV that generates see-saw masses of the right size. This model requires lepton minimal flavor violation (LMFV) in which only Yukawa matrices (present on the IR brane) break the flavor symmetries. The symmetry-breaking is transmitted to charged lepton bulk mass parameters as well to generate the hierarchy of charged lepton masses. With LMFV, a GIM-like mechanism prevents dangerous flavor-changing processes for charged leptons and permits flavor-changing processes only in the presence of the neutrino Yukawa interaction and are therefore suppressed when the overall scale for the neutrino Yukawa matrix is slightly smaller than one in units of the curvature. In this case the theory can be consistent with a cutoff of 10 TeV and 3 TeV Kaluza-Klein masses.
hep-ph/0308126
A. Yu. Ignatiev
A.Yu.Ignatiev, G.C.Joshi and B.H.J.McKellar
Spectator Effects in the Decay B -> K \gamma \gamma
5 pages, 5 figures, RevTeX 4
Int.J.Mod.Phys. A20 (2005) 4079-4084
10.1142/S0217751X0502495X
null
hep-ph
null
We report the results of the first computation related to the study of the spectator effects in the rare decay mode $B\to K \gamma \gamma $ within the framework of Standard Model. It is found that the account of these effects results in the enhancement factor for the short-distance reducible contribution to the branching ratio.
[ { "created": "Tue, 12 Aug 2003 02:59:46 GMT", "version": "v1" } ]
2009-11-10
[ [ "Ignatiev", "A. Yu.", "" ], [ "Joshi", "G. C.", "" ], [ "McKellar", "B. H. J.", "" ] ]
We report the results of the first computation related to the study of the spectator effects in the rare decay mode $B\to K \gamma \gamma $ within the framework of Standard Model. It is found that the account of these effects results in the enhancement factor for the short-distance reducible contribution to the branching ratio.
1211.0502
Fr\'ed\'eric Jugeau Dr.
Fr\'ed\'eric Jugeau
Hadronic linear potentials in AdS/CFT
Invited talk at the 7th International Conference on Mathematical Methods in Physics, Joint Conference: CBPF-IMPA-ICTP-SISSA-TWAS, Rio de Janeiro, Brazil, 16-20 April 2012. 7 pages. To appear in JHEP - PoS Proceedings of Science
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In 1998, J. M. Maldacena conjectured a precise duality in the low-energy (or decoupling) regime between a large N strongly-coupled SU(N) super-Yang-Mills theory defined in the four-dimensional Minkowski world-volume M^4 of a stack of N coincident D3-branes and the supergravity limit of a weakly-coupled type IIB closed superstring theory on AdS_5*S^5. This communication aims at introducing concepts and methods used to derive, in the gauge/string correspondence framework, the interaction potentials of mesons and baryons at zero and finite temperature. Especially, emphasize will be made on the linear behavior of the bound-state potentials derived in the gravity side. Although AdS/CFT cannot be applied ab initio to QCD-like gauge theories and remains a controversial topic, at least at zero temperature, we will also discuss AdS/QCD criteria proposed for a holographic description of the mechanism of confinement.
[ { "created": "Fri, 2 Nov 2012 17:49:35 GMT", "version": "v1" } ]
2012-11-05
[ [ "Jugeau", "Frédéric", "" ] ]
In 1998, J. M. Maldacena conjectured a precise duality in the low-energy (or decoupling) regime between a large N strongly-coupled SU(N) super-Yang-Mills theory defined in the four-dimensional Minkowski world-volume M^4 of a stack of N coincident D3-branes and the supergravity limit of a weakly-coupled type IIB closed superstring theory on AdS_5*S^5. This communication aims at introducing concepts and methods used to derive, in the gauge/string correspondence framework, the interaction potentials of mesons and baryons at zero and finite temperature. Especially, emphasize will be made on the linear behavior of the bound-state potentials derived in the gravity side. Although AdS/CFT cannot be applied ab initio to QCD-like gauge theories and remains a controversial topic, at least at zero temperature, we will also discuss AdS/QCD criteria proposed for a holographic description of the mechanism of confinement.
2109.08729
Mario Fern\'andez Navarro
Mario Fern\'andez Navarro and Stephen F. King
Fermiophobic $Z'$ model for simultaneously explaining the muon anomalies $R_{K^{(*)}}$ and $(g-2)_{\mu}$
26 pages, 12 Figures, 3 Tables
Phys. Rev. D 105, 035015 (2022)
10.1103/PhysRevD.105.035015
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
We discuss a simple renormalisable, gauge invariant model with a fermiophobic $Z'$ boson: it has no couplings to the three Standard Model (SM) chiral families, but does couple to a fourth vector-like (VL) family. The SM Higgs couples to the fourth VL lepton, leading to an enhanced contribution to the muon anomalous magnetic moment $\left(g-2\right)_{\mu}$. The latter contribution requires a non-vanishing coupling of $Z'$ to right-handed muons, which arises within this model due to mixing effects between the SM and VL fermions, along with $Z'$ couplings to the second generation SM lepton doublet and third generation SM quark doublet. This model can simultaneously account for the measured $B$-decay ratios $R_{K^{(*)}}$ and $\left(g-2\right)_{\mu}$. We identify the parameter space where this explanation is consistent with existing experimental constraints coming from $B_{s}-\bar{B}_{s}$ mixing, neutrino trident production and collider searches. We also check that the SM Higgs coupling to the fourth VL lepton does not produce a dangerous contribution to the Higgs diphoton decay.
[ { "created": "Fri, 17 Sep 2021 19:20:39 GMT", "version": "v1" }, { "created": "Sun, 26 Sep 2021 14:55:32 GMT", "version": "v2" }, { "created": "Wed, 29 Sep 2021 16:12:10 GMT", "version": "v3" }, { "created": "Fri, 1 Oct 2021 11:16:07 GMT", "version": "v4" }, { "created": "Thu, 2 Dec 2021 14:51:36 GMT", "version": "v5" } ]
2022-02-16
[ [ "Navarro", "Mario Fernández", "" ], [ "King", "Stephen F.", "" ] ]
We discuss a simple renormalisable, gauge invariant model with a fermiophobic $Z'$ boson: it has no couplings to the three Standard Model (SM) chiral families, but does couple to a fourth vector-like (VL) family. The SM Higgs couples to the fourth VL lepton, leading to an enhanced contribution to the muon anomalous magnetic moment $\left(g-2\right)_{\mu}$. The latter contribution requires a non-vanishing coupling of $Z'$ to right-handed muons, which arises within this model due to mixing effects between the SM and VL fermions, along with $Z'$ couplings to the second generation SM lepton doublet and third generation SM quark doublet. This model can simultaneously account for the measured $B$-decay ratios $R_{K^{(*)}}$ and $\left(g-2\right)_{\mu}$. We identify the parameter space where this explanation is consistent with existing experimental constraints coming from $B_{s}-\bar{B}_{s}$ mixing, neutrino trident production and collider searches. We also check that the SM Higgs coupling to the fourth VL lepton does not produce a dangerous contribution to the Higgs diphoton decay.
1706.09721
Zhaofeng Kang
Zhaofeng Kang, P. Ko and Toshinori Matsui
Strong First Order EWPT and Strong Gravitational Waves in $Z_3$-symmetric Singlet Scalar Extension
references added
null
10.1007/JHEP02(2018)115
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The nature of electroweak (EW) phase transition (PT) is of great importance. It may give a clue to the origin of baryon asymmetry if EWPT is strong first order. Although it is second order within the standard model (SM), a great many extensions of the SM are capable of altering the nature. Thus, gravitational wave (GW), which is supposed to be relics of strong first order PT, is a good complementary probe to new physics beyond SM (BSM). We in this paper elaborate the patterns of strong first order EWPT in the next to simplest extension to the SM Higgs sector, by introducing a $Z_3$-symmetric singlet scalar. We find that, in the $Z_3$-symmetric limit, the tree level barrier could lead to strong first order EWPT either via three or two-step PT. Moreover, they could produce two sources of GW, despite of the undetectability from the first-step strong first order PT for the near future GW experiments. But the other source with significant supercooling which then gives rise to $\alpha\sim{\cal O}(0.1)$ almost can be wholly covered by future space-based GW interferometers such as eLISA, DECIGO and BBO.
[ { "created": "Thu, 29 Jun 2017 12:44:37 GMT", "version": "v1" }, { "created": "Sun, 9 Jul 2017 15:39:07 GMT", "version": "v2" } ]
2018-04-04
[ [ "Kang", "Zhaofeng", "" ], [ "Ko", "P.", "" ], [ "Matsui", "Toshinori", "" ] ]
The nature of electroweak (EW) phase transition (PT) is of great importance. It may give a clue to the origin of baryon asymmetry if EWPT is strong first order. Although it is second order within the standard model (SM), a great many extensions of the SM are capable of altering the nature. Thus, gravitational wave (GW), which is supposed to be relics of strong first order PT, is a good complementary probe to new physics beyond SM (BSM). We in this paper elaborate the patterns of strong first order EWPT in the next to simplest extension to the SM Higgs sector, by introducing a $Z_3$-symmetric singlet scalar. We find that, in the $Z_3$-symmetric limit, the tree level barrier could lead to strong first order EWPT either via three or two-step PT. Moreover, they could produce two sources of GW, despite of the undetectability from the first-step strong first order PT for the near future GW experiments. But the other source with significant supercooling which then gives rise to $\alpha\sim{\cal O}(0.1)$ almost can be wholly covered by future space-based GW interferometers such as eLISA, DECIGO and BBO.
hep-ph/9706345
Jose Bernabeu
Jose Bernabeu
CP-Violation
40 pages, Latex with sprocl.sty and 15 figures included
null
null
FTUV/97-26
hep-ph
null
These lectures cover different aspects of the subject of CP-Violation, from its description inside the Standard Model to the phenomenological analysis of the $K^0 - \bar{K}^0$ system and the prospects for its manifestation in B-physics.
[ { "created": "Thu, 12 Jun 1997 17:47:16 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bernabeu", "Jose", "" ] ]
These lectures cover different aspects of the subject of CP-Violation, from its description inside the Standard Model to the phenomenological analysis of the $K^0 - \bar{K}^0$ system and the prospects for its manifestation in B-physics.
1307.7526
Kei Yagyu
Cheng-Wei Chiang, An-Li Kuo and Kei Yagyu
Enhancements of weak gauge boson scattering processes at the CERN LHC
18 pages, 14 figures
null
10.1007/JHEP10(2013)072
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Current CERN Large Hadron Collider data on the 126 GeV standard model-like Higgs boson suggest the possibility of larger Higgs boson couplings with the weak gauge bosons, $g_{hVV}$, than those in the standard model. We use the Georgi-Machacek model as an explicit model to realize such a scenario. We find that the $g_{hVV}$ couplings can be larger than the standard model value by a factor of about 1.3 maximally in the parameter region consistent with the current Higgs boson search data and allowed by various other constraints. We then show how the modified $g_{hVV}$ couplings lead to enhancements in various weak boson scattering processes. This can be clearly observed as excesses in the transverse mass distributions at around 126 GeV and also the mass of heavy Higgs bosons.
[ { "created": "Mon, 29 Jul 2013 10:22:34 GMT", "version": "v1" } ]
2015-06-16
[ [ "Chiang", "Cheng-Wei", "" ], [ "Kuo", "An-Li", "" ], [ "Yagyu", "Kei", "" ] ]
Current CERN Large Hadron Collider data on the 126 GeV standard model-like Higgs boson suggest the possibility of larger Higgs boson couplings with the weak gauge bosons, $g_{hVV}$, than those in the standard model. We use the Georgi-Machacek model as an explicit model to realize such a scenario. We find that the $g_{hVV}$ couplings can be larger than the standard model value by a factor of about 1.3 maximally in the parameter region consistent with the current Higgs boson search data and allowed by various other constraints. We then show how the modified $g_{hVV}$ couplings lead to enhancements in various weak boson scattering processes. This can be clearly observed as excesses in the transverse mass distributions at around 126 GeV and also the mass of heavy Higgs bosons.
1604.02658
Martin Spinrath
Martin Spinrath
Sum Rules for Leptons
9 pages, contribution to the International Conference on New Physics at the Large Hadron Collider, Singapore, 29 February - 4 March 2016
International Journal of Modern Physics A, Vol. 31 (2016) 1630021
10.1142/S0217751X16300210
TTP16-012
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
There is a wide class of models which give a dynamical description of the origin of flavour in terms of spontaneous symmetry breaking of an underlying symmetry. Many of these models exhibit sum rules which relate on the one hand mixing angles and the Dirac CP phase with each other and/or on the other hand neutrino masses and Majorana phases with each other. We will briefly sketch how this happens and discuss briefly the impact of renormalisation group corrections to the mass sum rules.
[ { "created": "Sun, 10 Apr 2016 09:18:34 GMT", "version": "v1" }, { "created": "Fri, 27 May 2016 08:26:25 GMT", "version": "v2" } ]
2016-05-30
[ [ "Spinrath", "Martin", "" ] ]
There is a wide class of models which give a dynamical description of the origin of flavour in terms of spontaneous symmetry breaking of an underlying symmetry. Many of these models exhibit sum rules which relate on the one hand mixing angles and the Dirac CP phase with each other and/or on the other hand neutrino masses and Majorana phases with each other. We will briefly sketch how this happens and discuss briefly the impact of renormalisation group corrections to the mass sum rules.
hep-ph/0101130
John F. Donoghue
John F. Donoghue
Spatial gradients in the cosmological constant
12 pages
JHEP 0303 (2003) 052
10.1088/1126-6708/2003/03/052
null
hep-ph astro-ph hep-th
null
It is possible that there may be differences in the fundamental physical parameters from one side of the observed universe to the other. I show that the cosmological constant is likely to be the most sensitive of the physical parameters to possible spatial variation, because a small variation in any of the other parameters produces a huge variation of the cosmological constant. It therefore provides a very powerful {\em indirect} evidence against spatial gradients or temporal variation in the other fundamental physical parameters, at least 40 orders of magnitude more powerful than direct experimental constraints. Moreover, a gradient may potentially appear in theories where the variability of the cosmological constant is connected to an anthropic selection mechanism, invoked to explain the smallness of this parameter. In the Hubble damping mechanism for anthropic selection, I calculate the possible gradient. While this mechanism demonstrates the existence of this effect, it is too small to be seen experimentally, except possibly if inflation happens around the Planck scale.
[ { "created": "Fri, 12 Jan 2001 16:43:05 GMT", "version": "v1" } ]
2009-11-07
[ [ "Donoghue", "John F.", "" ] ]
It is possible that there may be differences in the fundamental physical parameters from one side of the observed universe to the other. I show that the cosmological constant is likely to be the most sensitive of the physical parameters to possible spatial variation, because a small variation in any of the other parameters produces a huge variation of the cosmological constant. It therefore provides a very powerful {\em indirect} evidence against spatial gradients or temporal variation in the other fundamental physical parameters, at least 40 orders of magnitude more powerful than direct experimental constraints. Moreover, a gradient may potentially appear in theories where the variability of the cosmological constant is connected to an anthropic selection mechanism, invoked to explain the smallness of this parameter. In the Hubble damping mechanism for anthropic selection, I calculate the possible gradient. While this mechanism demonstrates the existence of this effect, it is too small to be seen experimentally, except possibly if inflation happens around the Planck scale.
0902.4507
Tao Liu
Vernon Barger, Lisa Everett, Jing Jiang, Paul Langacker, Tao Liu, Carlos E.M. Wagner
Family Non-universal $U(1)^\prime$ Gauge Symmetries and $b\to s$ Transitions
4 pages, 4 figures, FIG. 4 updated, references added
Phys.Rev.D80:055008,2009
10.1103/PhysRevD.80.055008
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a correlated analysis for the $\Delta B =1, 2$ processes which occur via $b\to s$ transitions within models with a family non-universal $U(1)^\prime$. We take a model-independent approach, and only require family universal charges for the first and second generations and small fermion mixing angles. The results of our analysis show that within this class of models, the anomalies in $B_s - \bar B_s$ mixing and the time-dependent CP asymmetries of the penguin-dominated $B_d \to (\pi, \phi, \eta', \rho, \omega, f_0)K_S$ decays can be accommodated.
[ { "created": "Thu, 26 Feb 2009 18:10:29 GMT", "version": "v1" }, { "created": "Sat, 16 May 2009 19:28:54 GMT", "version": "v2" } ]
2009-09-24
[ [ "Barger", "Vernon", "" ], [ "Everett", "Lisa", "" ], [ "Jiang", "Jing", "" ], [ "Langacker", "Paul", "" ], [ "Liu", "Tao", "" ], [ "Wagner", "Carlos E. M.", "" ] ]
We present a correlated analysis for the $\Delta B =1, 2$ processes which occur via $b\to s$ transitions within models with a family non-universal $U(1)^\prime$. We take a model-independent approach, and only require family universal charges for the first and second generations and small fermion mixing angles. The results of our analysis show that within this class of models, the anomalies in $B_s - \bar B_s$ mixing and the time-dependent CP asymmetries of the penguin-dominated $B_d \to (\pi, \phi, \eta', \rho, \omega, f_0)K_S$ decays can be accommodated.
hep-ph/0610369
Vladimir Zoller
V.R. Zoller
Left and Right in small-x neutrino DIS
7 pages, 1 figures, Talk given at Diffraction 06,International Workshop on Diffraction in High-Energy Physics,September 5-10, 2006 Adamantas, Milos island, Greece
PoSDIFF2006:042,2006
null
null
hep-ph
null
The color dipole analysis of nuclear effects in charge current DIS is presented. The emphasis is put on the pronounced effect of left-right asymmetry of shadowing in neutrino-nucleus DIS at small values of Bjorken $x$. Strikingly different scaling behavior of nuclear shadowing for the left-handed andright-handed $W^+$ is predicted. Large, about 25%, shadowing in the $Fe$ structure functions is predicted, which is important for a precise determination of the P-odd nucleon structure functions $xF^{\nu(\bar\nu)}_3$ and $\Delta x F_3=xF_3^{\nu}-xF_3^{\bar \nu}$.
[ { "created": "Fri, 27 Oct 2006 12:08:59 GMT", "version": "v1" } ]
2008-11-26
[ [ "Zoller", "V. R.", "" ] ]
The color dipole analysis of nuclear effects in charge current DIS is presented. The emphasis is put on the pronounced effect of left-right asymmetry of shadowing in neutrino-nucleus DIS at small values of Bjorken $x$. Strikingly different scaling behavior of nuclear shadowing for the left-handed andright-handed $W^+$ is predicted. Large, about 25%, shadowing in the $Fe$ structure functions is predicted, which is important for a precise determination of the P-odd nucleon structure functions $xF^{\nu(\bar\nu)}_3$ and $\Delta x F_3=xF_3^{\nu}-xF_3^{\bar \nu}$.
hep-ph/0112037
Robert D. Pisarski
Robert D. Pisarski
Tests of the Polyakov Loops Model
To appear in the Proceedings of "Statistical QCD", Bielefeld, August 26-30,2001
Nucl.Phys. A702 (2002) 151-158
10.1016/S0375-9474(02)00699-1
null
hep-ph
null
I give a brief review of the Polyakov Loops Model and tests thereof. I concentrate especially on how in a pure SU(N) gauge theory, Polyakov loops with Z(N) charges two and three affect the effective potential for charge-one loops.
[ { "created": "Tue, 4 Dec 2001 00:12:20 GMT", "version": "v1" } ]
2009-11-07
[ [ "Pisarski", "Robert D.", "" ] ]
I give a brief review of the Polyakov Loops Model and tests thereof. I concentrate especially on how in a pure SU(N) gauge theory, Polyakov loops with Z(N) charges two and three affect the effective potential for charge-one loops.
hep-ph/9810437
Boucaud
Ph. Boucaud, J.P. Leroy, J. Micheli, O. Pene and C. Roiesnel
Three-loop beta function and non-perturbative $\alpha_s$ in asymmetric momentum scheme
9 pages, LaTeX with two figures. The final analysis has been revisited to include an estimation of the systematic error coming from higher-order terms
JHEP 9812:004,1998
10.1088/1126-6708/1998/12/004
LPTHE Orsay-98/65
hep-ph hep-lat
null
We determine the three-loop coefficient of the beta function in the asymmetric momentum subtraction scheme in Landau gauge. This scheme is convenient for lattice studies of \alpha_s, the running coupling constant of QCD. We present high statistics lattice results for \alpha_s in the SU(3) Yang-Mills theory without quark, compare with the three-loop running and extract the value of the corresponding \Lambda_\msbar parameter. We estimate the systematic error coming from four-loop terms. We obtain the result: \Lambda_\msbar = 295 (5) (15) {a^{-1}(\beta=6.0) \over 1.97 GeV} MeV.
[ { "created": "Wed, 21 Oct 1998 17:15:37 GMT", "version": "v1" }, { "created": "Tue, 5 Jan 1999 18:11:54 GMT", "version": "v2" } ]
2010-03-19
[ [ "Boucaud", "Ph.", "" ], [ "Leroy", "J. P.", "" ], [ "Micheli", "J.", "" ], [ "Pene", "O.", "" ], [ "Roiesnel", "C.", "" ] ]
We determine the three-loop coefficient of the beta function in the asymmetric momentum subtraction scheme in Landau gauge. This scheme is convenient for lattice studies of \alpha_s, the running coupling constant of QCD. We present high statistics lattice results for \alpha_s in the SU(3) Yang-Mills theory without quark, compare with the three-loop running and extract the value of the corresponding \Lambda_\msbar parameter. We estimate the systematic error coming from four-loop terms. We obtain the result: \Lambda_\msbar = 295 (5) (15) {a^{-1}(\beta=6.0) \over 1.97 GeV} MeV.
1505.05030
Markus Wobisch
M. Wobisch, K. Rabbertz
Dijet azimuthal decorrelations for $\Delta \phi_{\rm dijet} < 2\pi/3$ in perturbative QCD
12 pages, 4 figures, 3 tables, submitted to JHEP
JHEP 12 (2015) 024
10.1007/JHEP12(2015)024
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We point out an inconsistency in perturbative QCD predictions previously used for dijet azimuthal decorrelations for azimuthal angles of $\Delta\phi_{\rm dijet} < 2\pi/3$ between the two jets. We show how the inconsistency arises and how the calculations can be modified to provide more accurate results that exhibit a smaller scale dependence and give a better description of the data than the inconsistent results. We also explain how the quality of the predictions strongly depends on a perceivedly minor detail in the definition of the dijet phase space and give recommendations for future measurements.
[ { "created": "Tue, 19 May 2015 14:53:59 GMT", "version": "v1" } ]
2021-12-01
[ [ "Wobisch", "M.", "" ], [ "Rabbertz", "K.", "" ] ]
We point out an inconsistency in perturbative QCD predictions previously used for dijet azimuthal decorrelations for azimuthal angles of $\Delta\phi_{\rm dijet} < 2\pi/3$ between the two jets. We show how the inconsistency arises and how the calculations can be modified to provide more accurate results that exhibit a smaller scale dependence and give a better description of the data than the inconsistent results. We also explain how the quality of the predictions strongly depends on a perceivedly minor detail in the definition of the dijet phase space and give recommendations for future measurements.
2006.11225
Patrick Foldenauer
Dorian Warren Praia do Amaral, David G. Cerdeno, Patrick Foldenauer, and Elliott Reid
Solar neutrino probes of the muon anomalous magnetic moment in the gauged $U(1)_{L_\mu-L_\tau}$
21 pages + appendices and references, 8 figures; v2: added references, updated description of loop-induced kinetic mixing suitable for low-energy processes; v3: matches published version
J. High Energ. Phys. 2020, 155 (2020)
10.1007/JHEP12(2020)155
IPPP/20/24, IFT-UAM/CSIC-20-70
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Models of gauged $U(1)_{L_\mu-L_\tau}$ can provide a solution to the long-standing discrepancy between the theoretical prediction for the muon anomalous magnetic moment and its measured value. The extra contribution is due to a new light vector mediator, which also helps to alleviate an existing tension in the determination of the Hubble parameter. In this article, we explore ways to probe this solution via the scattering of solar neutrinos with electrons and nuclei in a range of experiments and considering high and low solar metallicity scenarios. In particular, we reevaluate Borexino constraints on neutrino-electron scattering, finding them to be more stringent than previously reported, and already excluding a part of the $(g-2)_\mu$ explanation with mediator masses smaller than $2\times10^{-2}$ GeV. We then show that future direct dark matter detectors will be able to probe most of the remaining solution. Due to its large exposure, LUX-ZEPLIN will explore regions with mediator masses up to $5\times10^{-2}$ GeV and DARWIN will be able to extend the search beyond $10^{-1}$ GeV, thereby covering most of the area compatible with $(g-2)_\mu$. For completeness, we have also computed the constraints derived from the recent XENON1T electron recoil search and from the CENNS-10 LAr detector, showing that none of them excludes new areas of the parameter space. Should the excess in the muon anomalous magnetic moment be confirmed, our work suggests that direct detection experiments could provide crucial information with which to test the $U(1)_{L_\mu-L_\tau}$ solution, complementary to efforts in neutrino experiments and accelerators.
[ { "created": "Fri, 19 Jun 2020 16:59:15 GMT", "version": "v1" }, { "created": "Fri, 3 Jul 2020 15:20:55 GMT", "version": "v2" }, { "created": "Fri, 15 Jan 2021 14:15:14 GMT", "version": "v3" } ]
2021-01-18
[ [ "Amaral", "Dorian Warren Praia do", "" ], [ "Cerdeno", "David G.", "" ], [ "Foldenauer", "Patrick", "" ], [ "Reid", "Elliott", "" ] ]
Models of gauged $U(1)_{L_\mu-L_\tau}$ can provide a solution to the long-standing discrepancy between the theoretical prediction for the muon anomalous magnetic moment and its measured value. The extra contribution is due to a new light vector mediator, which also helps to alleviate an existing tension in the determination of the Hubble parameter. In this article, we explore ways to probe this solution via the scattering of solar neutrinos with electrons and nuclei in a range of experiments and considering high and low solar metallicity scenarios. In particular, we reevaluate Borexino constraints on neutrino-electron scattering, finding them to be more stringent than previously reported, and already excluding a part of the $(g-2)_\mu$ explanation with mediator masses smaller than $2\times10^{-2}$ GeV. We then show that future direct dark matter detectors will be able to probe most of the remaining solution. Due to its large exposure, LUX-ZEPLIN will explore regions with mediator masses up to $5\times10^{-2}$ GeV and DARWIN will be able to extend the search beyond $10^{-1}$ GeV, thereby covering most of the area compatible with $(g-2)_\mu$. For completeness, we have also computed the constraints derived from the recent XENON1T electron recoil search and from the CENNS-10 LAr detector, showing that none of them excludes new areas of the parameter space. Should the excess in the muon anomalous magnetic moment be confirmed, our work suggests that direct detection experiments could provide crucial information with which to test the $U(1)_{L_\mu-L_\tau}$ solution, complementary to efforts in neutrino experiments and accelerators.
1004.4032
Xiang Liu
Bin Hu, Xiao-Lin Chen, Zhi-Gang Luo, Peng-Zhi Huang, Shi-Lin Zhu, Peng-Fei Yu and Xiang Liu
Possible heavy molecular states composed of a pair of excited charm-strange mesons
15 pages, 12 tables. More dicussions added and typos corrected. Accepted for publication in Chinese Physics C
Chin.Phys.C35:113-125,2011
10.1088/1674-1137/35/2/002
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The P-wave charm-strange mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ lie below the $DK$ and $D^\ast K$ threshold respectively. They are extremely narrow because their strong decays violate the isospin symmetry. We study the possible heavy molecular states composed of a pair of excited charm strange mesons. As a byproduct, we also present the numerical results for the bottonium-like analogue.
[ { "created": "Fri, 23 Apr 2010 00:28:13 GMT", "version": "v1" }, { "created": "Tue, 27 Apr 2010 09:17:35 GMT", "version": "v2" }, { "created": "Fri, 30 Apr 2010 12:23:47 GMT", "version": "v3" }, { "created": "Mon, 7 Jun 2010 14:28:49 GMT", "version": "v4" } ]
2011-03-18
[ [ "Hu", "Bin", "" ], [ "Chen", "Xiao-Lin", "" ], [ "Luo", "Zhi-Gang", "" ], [ "Huang", "Peng-Zhi", "" ], [ "Zhu", "Shi-Lin", "" ], [ "Yu", "Peng-Fei", "" ], [ "Liu", "Xiang", "" ] ]
The P-wave charm-strange mesons $D_{s0}(2317)$ and $D_{s1}(2460)$ lie below the $DK$ and $D^\ast K$ threshold respectively. They are extremely narrow because their strong decays violate the isospin symmetry. We study the possible heavy molecular states composed of a pair of excited charm strange mesons. As a byproduct, we also present the numerical results for the bottonium-like analogue.
hep-ph/0004111
Rusko Ruskov
Alexander P. Bakulev (Dubna, JINR), Rusko Ruskov (Dubna, JINR), Klaus Goeke (Ruhr U., Bochum), N.G. Stefanis (Ruhr U., Bochum)
Parton Skewed Distributions in the Pion and Quark-Hadron Duality
16 pages, LaTeX, 9 eps figures, revtex, aps, floats, psbox.tex, corrected typos, changed slightly text, version to be published in Phys.Rev.D
Phys.Rev.D62:054018,2000
10.1103/PhysRevD.62.054018
JINR-E2-2000-78, RUB-TPII-05/00
hep-ph
null
Applying arguments based on the operator product expansion for a three-point correlator and relying on quark-hadron duality, we derive an expression for the skewed (non-forward) parton distribution in the pion in the case of a zero-skewedness parameter, {\cal F}^{\psi|\pi}_{\zeta=0}(X;t). We expect that our result is relevant for moderately large momentum transfers 1 < t < 10 GeV^2. In addition, we construct a purely phenomenological factorized model for the same quantity in close analogy to Radyushkin's model, originally proposed for skewed distributions of quarks in the nucleon. Though the quark-hadron duality approach supports theoretically the factorized model, the two models exhibit a different behavior in the parton momentum fraction X at any fixed t. The relevant process to distinguish between the two options seems to be the WACS off the pion that measures (to leading t/s-order) the inverse moment <X^{-1}> of the skewed distribution. Even after the inclusion of the first order kinematic t/s-corrections, the predictions for the cross section \frac{d \sigma}{d t}(s,t) at c.m.s. scattering angles \vartheta=30^{\circ} and 90^{\circ} differ by factors 3.5--3.9 and 2.9--7.5, respectively, so that a discrimination appears possible.
[ { "created": "Wed, 12 Apr 2000 12:03:38 GMT", "version": "v1" }, { "created": "Wed, 24 May 2000 18:06:20 GMT", "version": "v2" } ]
2009-08-25
[ [ "Bakulev", "Alexander P.", "", "Dubna, JINR" ], [ "Ruskov", "Rusko", "", "Dubna, JINR" ], [ "Goeke", "Klaus", "", "Ruhr U., Bochum" ], [ "Stefanis", "N. G.", "", "Ruhr U., Bochum" ] ]
Applying arguments based on the operator product expansion for a three-point correlator and relying on quark-hadron duality, we derive an expression for the skewed (non-forward) parton distribution in the pion in the case of a zero-skewedness parameter, {\cal F}^{\psi|\pi}_{\zeta=0}(X;t). We expect that our result is relevant for moderately large momentum transfers 1 < t < 10 GeV^2. In addition, we construct a purely phenomenological factorized model for the same quantity in close analogy to Radyushkin's model, originally proposed for skewed distributions of quarks in the nucleon. Though the quark-hadron duality approach supports theoretically the factorized model, the two models exhibit a different behavior in the parton momentum fraction X at any fixed t. The relevant process to distinguish between the two options seems to be the WACS off the pion that measures (to leading t/s-order) the inverse moment <X^{-1}> of the skewed distribution. Even after the inclusion of the first order kinematic t/s-corrections, the predictions for the cross section \frac{d \sigma}{d t}(s,t) at c.m.s. scattering angles \vartheta=30^{\circ} and 90^{\circ} differ by factors 3.5--3.9 and 2.9--7.5, respectively, so that a discrimination appears possible.
1410.3413
Boris Kerbikov
B.O. Kerbikov, M.A. Andreichikov
Electrical Conductivity of Dense Quark Matter with Fluctuations and Magnetic Field Included
null
Phys. Rev. D 91, 074010 (2015)
10.1103/PhysRevD.91.074010
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the electrical conductivity(EC) of dense quark matter in the vicinity of the phase transition line. We show that: (i) At high density the Drude EC does not depend on the magnetic field up to $eB \sim 10^{19} \ G$. (ii) In the precritical region the fluctuation EC (paraconductivity) dominates over the Drude one.
[ { "created": "Mon, 13 Oct 2014 17:52:59 GMT", "version": "v1" }, { "created": "Sat, 18 Oct 2014 10:42:56 GMT", "version": "v2" }, { "created": "Mon, 2 Mar 2015 13:31:07 GMT", "version": "v3" } ]
2015-04-16
[ [ "Kerbikov", "B. O.", "" ], [ "Andreichikov", "M. A.", "" ] ]
We investigate the electrical conductivity(EC) of dense quark matter in the vicinity of the phase transition line. We show that: (i) At high density the Drude EC does not depend on the magnetic field up to $eB \sim 10^{19} \ G$. (ii) In the precritical region the fluctuation EC (paraconductivity) dominates over the Drude one.
hep-ph/9710481
Arnd Leike
A. Leike
Form factors and radiative Corrections in Z' Physics
One reference added, 13 pages Latex, 1 figure, uses appb.sty (included) and epsf.sty, Lecture given at the XXI school of Theoretical Physics of the Katowice Univ., ``Recent progress in theory and phenomenology of fundamental interactions'', Ustro\'n, September 97
Acta Phys.Polon.B28:2495-2507,1997
null
LMU-14/97
hep-ph
null
This lecture contains a pedagogical approach to the description of Z' physics in the formalism of form factors. Usually, only electroweak corrections are described by form factors, which modify the Weinberg angle and the overall normalization. It is demonstrated how this formalism can be extended to include different Born contributions. In the second part of the lecture, QCD and QED corrections are considered. The development and consequences of the radiative tail for a Z' search are discussed in detail.
[ { "created": "Mon, 27 Oct 1997 12:17:58 GMT", "version": "v1" }, { "created": "Wed, 29 Oct 1997 14:07:35 GMT", "version": "v2" } ]
2011-04-15
[ [ "Leike", "A.", "" ] ]
This lecture contains a pedagogical approach to the description of Z' physics in the formalism of form factors. Usually, only electroweak corrections are described by form factors, which modify the Weinberg angle and the overall normalization. It is demonstrated how this formalism can be extended to include different Born contributions. In the second part of the lecture, QCD and QED corrections are considered. The development and consequences of the radiative tail for a Z' search are discussed in detail.
1804.00019
Mohammad Alhakami
Mohammad H. Alhakami
Low-energy constants of heavy meson effective theory in lattice QCD
null
Phys. Rev. D 98, 016008 (2018)
10.1103/PhysRevD.98.016008
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider effective theory treatment for the lowest-lying $S$- and $P$-wave states of charmed mesons. In our analysis, quantum corrections and contributions from leading chiral and heavy quark symmetry breakings are taken into account. The heavy meson mass expressions have abundance parameters, low-energy constants, in comparison to the measured charmed mesons masses. The experimental and lattice QCD data on charmed meson spectroscopy are used to extract, for the first time, the numerical values of the full set of low-energy constants of the effective chiral Lagrangian. Our results on these parameters can be used for applications on other properties of heavy-light meson systems.
[ { "created": "Fri, 30 Mar 2018 18:17:03 GMT", "version": "v1" }, { "created": "Sun, 22 Jul 2018 12:57:16 GMT", "version": "v2" } ]
2018-07-24
[ [ "Alhakami", "Mohammad H.", "" ] ]
We consider effective theory treatment for the lowest-lying $S$- and $P$-wave states of charmed mesons. In our analysis, quantum corrections and contributions from leading chiral and heavy quark symmetry breakings are taken into account. The heavy meson mass expressions have abundance parameters, low-energy constants, in comparison to the measured charmed mesons masses. The experimental and lattice QCD data on charmed meson spectroscopy are used to extract, for the first time, the numerical values of the full set of low-energy constants of the effective chiral Lagrangian. Our results on these parameters can be used for applications on other properties of heavy-light meson systems.