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1810.02484
Francis Halzen
Francis Halzen
The Anisotropies and Origins of Ultrahigh Energy Cosmic Rays
20 pages, 5 figures, CIPANP 2018 proceeding
null
null
CIPANP2018-Halzen
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
IceCube detects more than 100,000 neutrinos per year in the GeV- to PeV-energy range. Among those, we have isolated a flux of high-energy cosmic neutrinos. I will discuss the instrument, the analysis of the data, the significance of the discovery of cosmic neutrinos, and the recent multi-messenger observation of a flaring TeV blazar in coincidence with the IceCube neutrino alert IC170922.
[ { "created": "Thu, 4 Oct 2018 14:42:40 GMT", "version": "v1" } ]
2018-10-09
[ [ "Halzen", "Francis", "" ] ]
IceCube detects more than 100,000 neutrinos per year in the GeV- to PeV-energy range. Among those, we have isolated a flux of high-energy cosmic neutrinos. I will discuss the instrument, the analysis of the data, the significance of the discovery of cosmic neutrinos, and the recent multi-messenger observation of a flaring TeV blazar in coincidence with the IceCube neutrino alert IC170922.
hep-ph/0004152
R. D. Peccei
R. D. Peccei
BCP3: Summary of Theory
To appear in the Proceedings of the Third International Conference on B Physics and CP Violation, Taipei, Taiwan, December 3-7, 1999
null
10.1142/9789812791870_0072
null
hep-ph
null
I discuss a number of the highlights in theory presented at the BCP3 conference. These included new, and more stringent, CKM fits; a critical overview of heavy hadron lifetimes; progress in computing rates and CP-asymmetries in charmless B-decays; a thorough discussion of the implications of the new results on $\epsilon^{\prime}/\epsilon$; and, finally, a peek at the future, trying to estimate how well one is going to be able to measure the unitarity triangle angles.
[ { "created": "Sun, 16 Apr 2000 20:37:13 GMT", "version": "v1" } ]
2016-11-23
[ [ "Peccei", "R. D.", "" ] ]
I discuss a number of the highlights in theory presented at the BCP3 conference. These included new, and more stringent, CKM fits; a critical overview of heavy hadron lifetimes; progress in computing rates and CP-asymmetries in charmless B-decays; a thorough discussion of the implications of the new results on $\epsilon^{\prime}/\epsilon$; and, finally, a peek at the future, trying to estimate how well one is going to be able to measure the unitarity triangle angles.
0901.4596
Koichi Yoshioka
Naoyuki Haba, Shigeki Matsumoto, Koichi Yoshioka
Observable Seesaw and its Collider Signatures
13 pages, 4 figures
Phys.Lett.B677:291-295,2009
10.1016/j.physletb.2009.05.042
OU-HET 622/2009, UT-HET 023, KUNS-2186
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the scenario with TeV-scale right-handed neutrinos, which are accessible at future colliders, while holding down tiny seesaw-induced masses and sizable couplings to the standard-model particles. The signal with tri-lepton final states and large missing transverse energy is appropriate for studying collider signatures of the scenario with extra spatial dimensions. We show that the LHC experiment generally has a potential to discover the signs of extra dimensions and the origin of small neutrino masses.
[ { "created": "Thu, 29 Jan 2009 02:39:43 GMT", "version": "v1" } ]
2009-11-19
[ [ "Haba", "Naoyuki", "" ], [ "Matsumoto", "Shigeki", "" ], [ "Yoshioka", "Koichi", "" ] ]
We discuss the scenario with TeV-scale right-handed neutrinos, which are accessible at future colliders, while holding down tiny seesaw-induced masses and sizable couplings to the standard-model particles. The signal with tri-lepton final states and large missing transverse energy is appropriate for studying collider signatures of the scenario with extra spatial dimensions. We show that the LHC experiment generally has a potential to discover the signs of extra dimensions and the origin of small neutrino masses.
hep-ph/0605140
J. Jesus Toscano
C. G. Honorato, J. J. Toscano
Production of doubly charged vector bilepton pairs at $\gamma \gamma$ colliders
9 pages, 7 figures, submitted to physical review D
Phys.Rev.D73:095007,2006
10.1103/PhysRevD.73.095007
null
hep-ph
null
The production of pairs of doubly charged vector bileptons is studied at future $\gamma \gamma$ colliders. The unpolarized cross--section for the $\gamma \gamma \to Y^{--}Y^{++}$ subprocess is analytically calculated and convoluted to predict the number of events in the complete $e^+e^-\to \gamma \gamma \to Y^{--}Y^{++}$ process. The gauge or non--gauge character of the vector bilepton $Y^{\pm \pm}$ is discussed. It is found that as a consequence of its spectacular signature, as it decays dominantly into two identical charged leptons, and also due to its charge contents, which significantly enhance the cross--section, the detection of this class of particles with mass in the sub--TeV region can be at the reach of these colliders. The model--independent nature of our results is stressed.
[ { "created": "Thu, 11 May 2006 21:21:37 GMT", "version": "v1" } ]
2008-11-26
[ [ "Honorato", "C. G.", "" ], [ "Toscano", "J. J.", "" ] ]
The production of pairs of doubly charged vector bileptons is studied at future $\gamma \gamma$ colliders. The unpolarized cross--section for the $\gamma \gamma \to Y^{--}Y^{++}$ subprocess is analytically calculated and convoluted to predict the number of events in the complete $e^+e^-\to \gamma \gamma \to Y^{--}Y^{++}$ process. The gauge or non--gauge character of the vector bilepton $Y^{\pm \pm}$ is discussed. It is found that as a consequence of its spectacular signature, as it decays dominantly into two identical charged leptons, and also due to its charge contents, which significantly enhance the cross--section, the detection of this class of particles with mass in the sub--TeV region can be at the reach of these colliders. The model--independent nature of our results is stressed.
hep-ph/9810337
Piotr Zenczykowski
P. Zenczykowski (Institute of Nuclear Physics, Krakow)
Weak Radiative Hyperon Decays and Vector Meson Dominance
Talk given at 3rd International Conference on Hyperons, Charm and Beauty Hadrons, Genoa, Italy, 30 Jun - 3 Jul 1998; To appear in Nuclear Physics B, Proceedings Supplements; 4 pages, LaTeX, uses espcrc2.sty (can be obtained from http://www.nucphys.nl)
Nucl.Phys.Proc.Suppl. 75B (1999) 53-56
10.1016/S0920-5632(99)00323-0
null
hep-ph
null
We study the question whether the phenomenologically successful VMD approach to weak radiative hyperon decays can be made consistent with Hara's theorem and still yield the pattern of asymmetries exhibited by experimental data. It appears that an essential ingredient which governs the pattern of asymmetries is the off-shell behaviour of the input electromagnetic 1/2^- 1/2^+ \gamma couplings. Although this behaviour can be chosen in such a way that the experimentally observed pattern is obtained, and yet Hara's theorem satisfied, at the same time the approach yields a definite prediction for the size of weak meson-nucleon coupling constants. Comparison with experiment reveals then another conflict.
[ { "created": "Tue, 13 Oct 1998 09:17:12 GMT", "version": "v1" } ]
2009-10-31
[ [ "Zenczykowski", "P.", "", "Institute of Nuclear Physics, Krakow" ] ]
We study the question whether the phenomenologically successful VMD approach to weak radiative hyperon decays can be made consistent with Hara's theorem and still yield the pattern of asymmetries exhibited by experimental data. It appears that an essential ingredient which governs the pattern of asymmetries is the off-shell behaviour of the input electromagnetic 1/2^- 1/2^+ \gamma couplings. Although this behaviour can be chosen in such a way that the experimentally observed pattern is obtained, and yet Hara's theorem satisfied, at the same time the approach yields a definite prediction for the size of weak meson-nucleon coupling constants. Comparison with experiment reveals then another conflict.
0801.1928
Michael E. Peskin
Michael E. Peskin
Supersymmetry in Elementary Particle Physics
75 pages, 36 figures
null
null
SLAC-PUB-13079
hep-ph
null
These lectures, presented at the 2006 TASI summer school, give a general introduction to supersymmetry, emphasizing its application to models of elementary particle physics at the 100 GeV energy scale. I discuss the following topics: the construction of supersymmetric Lagrangians with scalars, fermions, and gauge bosons, the structure and mass spectrum of the Minimal Supersymmetric Standard Model (MSSM), the measurement of the parameters of the MSSM at high-energy colliders, and the solutions that the MSSM gives to the problems of electroweak symmetry breaking and dark matter.
[ { "created": "Sun, 13 Jan 2008 01:22:05 GMT", "version": "v1" } ]
2008-01-15
[ [ "Peskin", "Michael E.", "" ] ]
These lectures, presented at the 2006 TASI summer school, give a general introduction to supersymmetry, emphasizing its application to models of elementary particle physics at the 100 GeV energy scale. I discuss the following topics: the construction of supersymmetric Lagrangians with scalars, fermions, and gauge bosons, the structure and mass spectrum of the Minimal Supersymmetric Standard Model (MSSM), the measurement of the parameters of the MSSM at high-energy colliders, and the solutions that the MSSM gives to the problems of electroweak symmetry breaking and dark matter.
2111.02442
Richard Ruiz
Richard Ruiz, Antonio Costantini, Fabio Maltoni, and Olivier Mattelaer
The Effective Vector Boson Approximation in High-Energy Muon Collisions
Journal version + appendix. 66 pages (total), 11 figures, 10 tables. Support for W/Z PDFs available starting from MG5aMC@NLO version 3.3.0. Results unchanged
JHEP 2022, 114 (2022)
10.1007/JHEP06(2022)114
CP3-21-59, IFJPAN-IV-2021-17, MCNET-21-13, VBSCAN-PUB-07-21
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Due to the inclination for forward gauge radiation, lepton colliders beyond a few TeV are effectively electroweak (EW) boson colliders, suggesting the treatment of EW bosons as constituents of high-energy leptons. In the context of a muon collider, we revisit the validity of $W$ and $Z$ parton distribution functions (PDFs) at leading order in $2\to n$ process. We systematically investigate universal and quasi-universal power-law and logarithmic corrections that arise when deriving (polarized) weak boson PDFs in the collinear limit. We go on to survey a multitude of $2\to n$ processes at $\sqrt{s}=2-30$ TeV via polarized and unpolarized EW boson fusion/scattering. To conduct this study, we report a public implementation of the Effective $W/Z$ and Weizs\"acker-Williams Approximations, which we collectively call the Effective Vector Boson Approximation, into the Monte Carlo event generator \texttt{MadGraph5\_aMC@NLO}. This implementation lays the groundwork for developing matrix-element matching prescriptions involving EW parton showers and renormalized EW PDFs. To further with this agenda, we give recommendations on using $W/Z$ PDFs.
[ { "created": "Wed, 3 Nov 2021 18:02:55 GMT", "version": "v1" }, { "created": "Thu, 23 Jun 2022 18:19:17 GMT", "version": "v2" } ]
2022-06-27
[ [ "Ruiz", "Richard", "" ], [ "Costantini", "Antonio", "" ], [ "Maltoni", "Fabio", "" ], [ "Mattelaer", "Olivier", "" ] ]
Due to the inclination for forward gauge radiation, lepton colliders beyond a few TeV are effectively electroweak (EW) boson colliders, suggesting the treatment of EW bosons as constituents of high-energy leptons. In the context of a muon collider, we revisit the validity of $W$ and $Z$ parton distribution functions (PDFs) at leading order in $2\to n$ process. We systematically investigate universal and quasi-universal power-law and logarithmic corrections that arise when deriving (polarized) weak boson PDFs in the collinear limit. We go on to survey a multitude of $2\to n$ processes at $\sqrt{s}=2-30$ TeV via polarized and unpolarized EW boson fusion/scattering. To conduct this study, we report a public implementation of the Effective $W/Z$ and Weizs\"acker-Williams Approximations, which we collectively call the Effective Vector Boson Approximation, into the Monte Carlo event generator \texttt{MadGraph5\_aMC@NLO}. This implementation lays the groundwork for developing matrix-element matching prescriptions involving EW parton showers and renormalized EW PDFs. To further with this agenda, we give recommendations on using $W/Z$ PDFs.
1507.08560
Artur Ankowski
Artur M. Ankowski, Omar Benhar, Pilar Coloma, Patrick Huber, Chun-Min Jen, Camillo Mariani, Davide Meloni, and Erica Vagnoni
Comparison of the calorimetric and kinematic methods of neutrino energy reconstruction in disappearance experiments
16 pages, 14 figures, matches the version published in Phys. Rev. D
Phys. Rev. D 92, 073014 (2015)
10.1103/PhysRevD.92.073014
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
To be able to achieve their physics goals, future neutrino-oscillation experiments will need to reconstruct the neutrino energy with very high accuracy. In this work, we analyze how the energy reconstruction may be affected by realistic detection capabilities, such as energy resolutions, efficiencies, and thresholds. This allows us to estimate how well the detector performance needs to be determined a priori in order to avoid a sizable bias in the measurement of the relevant oscillation parameters. We compare the kinematic and calorimetric methods of energy reconstruction in the context of two muon-neutrino disappearance experiments operating in different energy regimes. For the calorimetric reconstruction method, we find that the detector performance has to be estimated with a ~10% accuracy to avoid a significant bias in the extracted oscillation parameters. On the other hand, in the case of kinematic energy reconstruction, we observe that the results exhibit less sensitivity to an overestimation of the detector capabilities.
[ { "created": "Thu, 30 Jul 2015 16:04:01 GMT", "version": "v1" }, { "created": "Wed, 5 Aug 2015 21:38:51 GMT", "version": "v2" }, { "created": "Thu, 22 Oct 2015 16:12:36 GMT", "version": "v3" } ]
2015-10-23
[ [ "Ankowski", "Artur M.", "" ], [ "Benhar", "Omar", "" ], [ "Coloma", "Pilar", "" ], [ "Huber", "Patrick", "" ], [ "Jen", "Chun-Min", "" ], [ "Mariani", "Camillo", "" ], [ "Meloni", "Davide", "" ], [ "Vagnoni", "Erica", "" ] ]
To be able to achieve their physics goals, future neutrino-oscillation experiments will need to reconstruct the neutrino energy with very high accuracy. In this work, we analyze how the energy reconstruction may be affected by realistic detection capabilities, such as energy resolutions, efficiencies, and thresholds. This allows us to estimate how well the detector performance needs to be determined a priori in order to avoid a sizable bias in the measurement of the relevant oscillation parameters. We compare the kinematic and calorimetric methods of energy reconstruction in the context of two muon-neutrino disappearance experiments operating in different energy regimes. For the calorimetric reconstruction method, we find that the detector performance has to be estimated with a ~10% accuracy to avoid a significant bias in the extracted oscillation parameters. On the other hand, in the case of kinematic energy reconstruction, we observe that the results exhibit less sensitivity to an overestimation of the detector capabilities.
2311.14398
Shakeel Mahmood
Shakeel Mahmood, Mudassir Hussain, Abrar Ahmad
Isospin Decomposition of D Mesons
9 Pages , 5 Figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by-sa/4.0/
This work focuses on decomposition of isospin amplitude of D meson non-leptonic decays. Isospin vector algebra is used to show the equivalency of two amplitude decompositions. We restrict to the transitions involving only Del I = 1 and Del I = 0: The isospin symmetry is relating charge channel (D+ -> K+,Pi+ Pi-; D+ -> K+, Pi0, Pi0 and D+-> K0, Pi0,Pi+); and neutral channel (D0 -> K0,Pi+,Pi- D0 -> K0, Pi0, Pi0 and D0 -> K+, Pi0, Pi-) with each other. Equivalent triangle relations are obtained for both channels.
[ { "created": "Fri, 24 Nov 2023 10:31:49 GMT", "version": "v1" } ]
2023-11-27
[ [ "Mahmood", "Shakeel", "" ], [ "Hussain", "Mudassir", "" ], [ "Ahmad", "Abrar", "" ] ]
This work focuses on decomposition of isospin amplitude of D meson non-leptonic decays. Isospin vector algebra is used to show the equivalency of two amplitude decompositions. We restrict to the transitions involving only Del I = 1 and Del I = 0: The isospin symmetry is relating charge channel (D+ -> K+,Pi+ Pi-; D+ -> K+, Pi0, Pi0 and D+-> K0, Pi0,Pi+); and neutral channel (D0 -> K0,Pi+,Pi- D0 -> K0, Pi0, Pi0 and D0 -> K+, Pi0, Pi-) with each other. Equivalent triangle relations are obtained for both channels.
hep-ph/9609436
Huang Ming-qiu
Yuan-ben Dai, Chao-shang Huang, Ming-qiu Huang, and Chun Liu
QCD Sum Rules for Masses of Excited Heavy Mesons
LateX, 12 pages including 2 figs
Phys.Lett. B390 (1997) 350-358
10.1016/S0370-2693(96)01412-8
AS-ITP-96-20
hep-ph
null
The masses of excited heavy mesons are studied with sum rules in the heavy quark effective theory. A set of interpolating currents creating (annihilating) excited heavy mesons with arbitrary spin and parity are proposed and their properties are discussed. Numerical results at the leading order of the {\cal O}(1/m_Q) expansion are obtained for the lowest doublets (0^+, 1^+) and (1^+, 2^+).
[ { "created": "Mon, 23 Sep 1996 08:59:36 GMT", "version": "v1" } ]
2015-06-25
[ [ "Dai", "Yuan-ben", "" ], [ "Huang", "Chao-shang", "" ], [ "Huang", "Ming-qiu", "" ], [ "Liu", "Chun", "" ] ]
The masses of excited heavy mesons are studied with sum rules in the heavy quark effective theory. A set of interpolating currents creating (annihilating) excited heavy mesons with arbitrary spin and parity are proposed and their properties are discussed. Numerical results at the leading order of the {\cal O}(1/m_Q) expansion are obtained for the lowest doublets (0^+, 1^+) and (1^+, 2^+).
hep-ph/0409227
Dong Won Lee
Dong Won Lee, Bjong Ro Kim and Sun Kun Oh
Implications of Constraints on Mass Parameters in the Higgs Sector of the Nonlinear Supersymmetric SU(5) Model
23 pages, 10 figures
Eur.Phys.J. C38 (2004) 349-357
10.1140/epjc/s2004-02050-9
null
hep-ph
null
The Higgs sector of the minimal nonlinear supersymmetric SU(5) model contains three mass parameters. Although these mass parameters are essentially free at the electroweak scale, they might have particular values if they evolve from a particular constraints at the GUT scale through the RG equations. By assuming a number of simple constraints on these mass parameters at the GUT scale, we obtain their values at the electroweak scale through the RG equations in order to investigate the phenomenological implications. Some of them are found to be consistent with the present experimental data.
[ { "created": "Mon, 20 Sep 2004 10:20:50 GMT", "version": "v1" } ]
2009-11-10
[ [ "Lee", "Dong Won", "" ], [ "Kim", "Bjong Ro", "" ], [ "Oh", "Sun Kun", "" ] ]
The Higgs sector of the minimal nonlinear supersymmetric SU(5) model contains three mass parameters. Although these mass parameters are essentially free at the electroweak scale, they might have particular values if they evolve from a particular constraints at the GUT scale through the RG equations. By assuming a number of simple constraints on these mass parameters at the GUT scale, we obtain their values at the electroweak scale through the RG equations in order to investigate the phenomenological implications. Some of them are found to be consistent with the present experimental data.
hep-ph/0307219
Sergey Alekhin
S.Alekhin (IHEP, Protvino)
The NNLO predictions for the rates of the W/Z production in pp and pbar p collisions
7 pages, LATEX, 3 figures (EPS). Contributed to 21th International Symposium on Lepton and Photon Interactions at High Energies (LP 03), 11-16 Aug 2003, Batavia, Illinois
null
null
null
hep-ph
null
The NNLO rates of the intermediate vector boson production (IVB) are calculated and found to agree with the preliminary results of Run II at the Fermilab pbar p collider. The estimated uncertainties in NNLO predictions for the IVB rates including the errors in PDFs, $\alpha_s$, and the factorization/renormalization scales are about 2% for the Fermilab collider and 3% for the LHC that allows to use these predictions as a competitive benchmark for calibration of the collision luminosity.
[ { "created": "Thu, 17 Jul 2003 08:36:40 GMT", "version": "v1" } ]
2007-05-23
[ [ "Alekhin", "S.", "", "IHEP, Protvino" ] ]
The NNLO rates of the intermediate vector boson production (IVB) are calculated and found to agree with the preliminary results of Run II at the Fermilab pbar p collider. The estimated uncertainties in NNLO predictions for the IVB rates including the errors in PDFs, $\alpha_s$, and the factorization/renormalization scales are about 2% for the Fermilab collider and 3% for the LHC that allows to use these predictions as a competitive benchmark for calibration of the collision luminosity.
hep-ph/0009275
Milo Svec
M.Svec
Unitarity and Interfering Resonances in pipi Scattering and in Pion Production piN->pipiN
31 pages
Phys.Rev. D64 (2001) 096003
10.1103/PhysRevD.64.096003
null
hep-ph
null
Additivity of Breit-Wigner phases has been proposed to describe interfering resonances in partial waves in $\pi\pi$ scattering. This assumption leads to an expression for partial wave amplitudes that involves products of Breit-Wigner amplitudes. We show that this expression is equivalent to a coherent sum of Breit-Wigner amplitudes with specific complex coefficients which depend on the resonance parameters of all contributing resonances. We use analyticity of $\pi\pi$ partial wave amplitudes to show that they must have the form of a coherent sum of Breit-Wigner amplitudes with complex coefficients and a complex coherent background. The assumption of additivity of Breit-Wigner phases restricts the partial waves to analytical functions with very specific form of residues of Breit-Wigner poles. We argue that the general form provided by the analyticity is more appropriate in fits to data to determine resonance parameters. The partial wave unitarity can be imposed using the modern methods of constrained optimization. We discuss unitarity and the production amplitudes in $\pi N\to\pi\pi N$ and use analyticity in the dipion mass variable to justify the common practice of writing the production amplitudes as a coherent sum of Breit-Wigner amplitudes with free complex coefficients and a complex coherent background in fits to mass spectra with interfering resonances.
[ { "created": "Fri, 22 Sep 2000 20:36:39 GMT", "version": "v1" }, { "created": "Mon, 18 Jun 2001 18:58:52 GMT", "version": "v2" } ]
2009-10-31
[ [ "Svec", "M.", "" ] ]
Additivity of Breit-Wigner phases has been proposed to describe interfering resonances in partial waves in $\pi\pi$ scattering. This assumption leads to an expression for partial wave amplitudes that involves products of Breit-Wigner amplitudes. We show that this expression is equivalent to a coherent sum of Breit-Wigner amplitudes with specific complex coefficients which depend on the resonance parameters of all contributing resonances. We use analyticity of $\pi\pi$ partial wave amplitudes to show that they must have the form of a coherent sum of Breit-Wigner amplitudes with complex coefficients and a complex coherent background. The assumption of additivity of Breit-Wigner phases restricts the partial waves to analytical functions with very specific form of residues of Breit-Wigner poles. We argue that the general form provided by the analyticity is more appropriate in fits to data to determine resonance parameters. The partial wave unitarity can be imposed using the modern methods of constrained optimization. We discuss unitarity and the production amplitudes in $\pi N\to\pi\pi N$ and use analyticity in the dipion mass variable to justify the common practice of writing the production amplitudes as a coherent sum of Breit-Wigner amplitudes with free complex coefficients and a complex coherent background in fits to mass spectra with interfering resonances.
0707.3044
Nanava Gizo
Z. Was, P. Golonka, G. Nanava
PHOTOS Monte Carlo for precision simulation of QED in decays - History and properties of the project
Prepared for XI International Workshop on Advanced Computing and Analysis Techniques in Physics Research, Amsterdam, the Netherlands, April 23 2007
PoSACAT:071,2007
null
IFJPAN-IV-2007-11, CERN-PH-TH/2007-124
hep-ph
null
Because of properties of QED, the bremsstrahlung corrections to decays of particles or resonances can be calculated, with a good precision, separately from other effects. Thanks to the widespread use of event records such calculations can be embodied into a separate module of Monte Carlo simulation chains, as used in High Energy Experiments of today. The PHOTOS Monte Carlo program is used for this purpose since nearly 20 years now. In the following talk let us review the main ideas and constraints which shaped the program version of today and enabled it widespread use. We will concentrate specially on conflicting requirements originating from the properties of QED matrix elements on one side and degrading (evolving) with time standards of event record(s). These issues, quite common in other modular software applications, become more and more difficult to handle as precision requirements become higher.
[ { "created": "Fri, 20 Jul 2007 11:30:18 GMT", "version": "v1" } ]
2008-11-26
[ [ "Was", "Z.", "" ], [ "Golonka", "P.", "" ], [ "Nanava", "G.", "" ] ]
Because of properties of QED, the bremsstrahlung corrections to decays of particles or resonances can be calculated, with a good precision, separately from other effects. Thanks to the widespread use of event records such calculations can be embodied into a separate module of Monte Carlo simulation chains, as used in High Energy Experiments of today. The PHOTOS Monte Carlo program is used for this purpose since nearly 20 years now. In the following talk let us review the main ideas and constraints which shaped the program version of today and enabled it widespread use. We will concentrate specially on conflicting requirements originating from the properties of QED matrix elements on one side and degrading (evolving) with time standards of event record(s). These issues, quite common in other modular software applications, become more and more difficult to handle as precision requirements become higher.
hep-ph/9607366
Matthias Neubert
Andrey G. Grozin (Budker Institute) and Matthias Neubert (CERN)
Asymptotics of Heavy-Meson Form Factors
34 pages RevTeX, 11 figures appended
Phys.Rev. D55 (1997) 272-290
10.1103/PhysRevD.55.272
Budker INP 96-45, CERN-TH/96-144
hep-ph
null
Using methods developed for hard exclusive QCD processes, we calculate the asymptotic behaviour of heavy-meson form factors at large recoil. It is determined by the leading- and subleading-twist meson wave functions. For $1\ll |v\cdot v'|\ll m_Q/\Lambda$, the form factors are dominated by the Isgur--Wise function, which is determined by the interference between the wave functions of leading and subleading twist. At $|v\cdot v'|\gg m_Q/\Lambda$, they are dominated by two functions arising at order $1/m_Q$ in the heavy-quark expansion, which are determined by the leading-twist wave function alone. The sum of these contributions describes the form factors in the whole region $|v\cdot v'|\gg 1$. As a consequence, there is an exact zero in the form factor for the scattering of longitudinally polarized $B^*$ mesons at some value $v\cdot v'\sim m_b/\Lambda$, and an approximate zero in the form factor of $B$ mesons in the timelike region ($v\cdot v'\sim -m_b/\Lambda$). We obtain the evolution equations and sum rules for the wave functions of leading and subleading twist as well as for their moments. We briefly discuss applications to heavy-meson pair production in $e^+ e^-$ collisions.
[ { "created": "Thu, 18 Jul 1996 09:08:38 GMT", "version": "v1" } ]
2009-10-28
[ [ "Grozin", "Andrey G.", "", "Budker Institute" ], [ "Neubert", "Matthias", "", "CERN" ] ]
Using methods developed for hard exclusive QCD processes, we calculate the asymptotic behaviour of heavy-meson form factors at large recoil. It is determined by the leading- and subleading-twist meson wave functions. For $1\ll |v\cdot v'|\ll m_Q/\Lambda$, the form factors are dominated by the Isgur--Wise function, which is determined by the interference between the wave functions of leading and subleading twist. At $|v\cdot v'|\gg m_Q/\Lambda$, they are dominated by two functions arising at order $1/m_Q$ in the heavy-quark expansion, which are determined by the leading-twist wave function alone. The sum of these contributions describes the form factors in the whole region $|v\cdot v'|\gg 1$. As a consequence, there is an exact zero in the form factor for the scattering of longitudinally polarized $B^*$ mesons at some value $v\cdot v'\sim m_b/\Lambda$, and an approximate zero in the form factor of $B$ mesons in the timelike region ($v\cdot v'\sim -m_b/\Lambda$). We obtain the evolution equations and sum rules for the wave functions of leading and subleading twist as well as for their moments. We briefly discuss applications to heavy-meson pair production in $e^+ e^-$ collisions.
1112.3379
Georgios Anagnostou
Georgios Anagnostou
Model Independent Search in 2-Dimensional Mass Space
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A model independent method to search for particles of unknown masses in events with missing energy is presented. The only assumption is the topology of the decay chain. The method is tested in events with top pairs decaying leptonically with the presence of two neutrinos in the final state. Possible applications are searches for a heavy resonance decaying to top pairs as well as next generation heavy quarks. Similar topologies are predicted by supersymmetric models with R-parity conservation resulting in final states with two invisible neutralinos.
[ { "created": "Wed, 14 Dec 2011 22:18:50 GMT", "version": "v1" } ]
2011-12-16
[ [ "Anagnostou", "Georgios", "" ] ]
A model independent method to search for particles of unknown masses in events with missing energy is presented. The only assumption is the topology of the decay chain. The method is tested in events with top pairs decaying leptonically with the presence of two neutrinos in the final state. Possible applications are searches for a heavy resonance decaying to top pairs as well as next generation heavy quarks. Similar topologies are predicted by supersymmetric models with R-parity conservation resulting in final states with two invisible neutralinos.
hep-ph/9507402
Georges Leontaris
E. G. Floratos, G. K. Leontaris and S. Lola
MSSM phenomenology in the large tanb regime
13 pages,latex file, 3 latex figures included. Version to appear in Phys. Lett. B
Phys.Lett.B365:149-156,1996
10.1016/0370-2693(95)01288-5
HD-THEP-95-28, IOA-226-95
hep-ph
null
We discuss aspects of the low energy phenomenology of the MSSM, in the large $\tan {\beta} $ regime. We explore the regions of the parameter space where the $h_t$ and $h_b$ Yukawa couplings exhibit a fixed point structure, using previous analytic solutions for these couplings. Expressions for the parameters $A_{t}$ and $A_{b}$ and the renormalised soft mass terms are also derived, making it possible to estimate analytically the sparticle loop -- corrections to the bottom mass, which are important in this limit.
[ { "created": "Tue, 25 Jul 1995 10:00:23 GMT", "version": "v1" }, { "created": "Wed, 18 Oct 1995 15:31:22 GMT", "version": "v2" } ]
2011-01-27
[ [ "Floratos", "E. G.", "" ], [ "Leontaris", "G. K.", "" ], [ "Lola", "S.", "" ] ]
We discuss aspects of the low energy phenomenology of the MSSM, in the large $\tan {\beta} $ regime. We explore the regions of the parameter space where the $h_t$ and $h_b$ Yukawa couplings exhibit a fixed point structure, using previous analytic solutions for these couplings. Expressions for the parameters $A_{t}$ and $A_{b}$ and the renormalised soft mass terms are also derived, making it possible to estimate analytically the sparticle loop -- corrections to the bottom mass, which are important in this limit.
hep-ph/0501109
Olga Lalakulich
Olga Lalakulich and Emmanuel A. Paschos
Resonance production by neutrinos: I. J=3/2 Resonances
10 pages, LaTeX, misprints corrected, 1 reference added
Phys.Rev. D71 (2005) 074003
10.1103/PhysRevD.71.074003
DO-TH-04/12
hep-ph
null
The article contains general formulas for the production of J=3/2 resonances by neutrinos and antineutrinos. It specializes to the P_{33}(1232) resonance whose form factors are determined by theory and experiment and then are compared with experimental results at low and high energies. It is shown that the minimum in the low Q^2 region is a consequence of a combined effect from the vanishing of the vector form factors, the muon mass and Pauli blocking. Several improvements for the future investigations are suggested.
[ { "created": "Thu, 13 Jan 2005 18:19:24 GMT", "version": "v1" }, { "created": "Wed, 9 Feb 2005 13:52:10 GMT", "version": "v2" } ]
2009-11-11
[ [ "Lalakulich", "Olga", "" ], [ "Paschos", "Emmanuel A.", "" ] ]
The article contains general formulas for the production of J=3/2 resonances by neutrinos and antineutrinos. It specializes to the P_{33}(1232) resonance whose form factors are determined by theory and experiment and then are compared with experimental results at low and high energies. It is shown that the minimum in the low Q^2 region is a consequence of a combined effect from the vanishing of the vector form factors, the muon mass and Pauli blocking. Several improvements for the future investigations are suggested.
hep-ph/0102312
Fjy
F. J. Yndurain
Disagreement between standard model and experiment for muon g-2 ?
New version with corrections and a few additions. Plain TeX file, 1 figure
null
null
null
hep-ph
null
In a recent experimental paper reporting a precise measurement of the muon anomalous magnetic moment, Brown et al. claim disagreement of their result with evaluations based on the standard model. This claim is based on comparison with a single theoretical evaluation. It is pointed out that other equally legitimate theoretical evaluations exist in the literature, with which the new experimental figure is quite compatible. The claim of indications for new physics beyond the standard model does not appear justified. In this version we take into account corrections to one of the works quoted, we include a new discussion at the end, and also minor errors are corrected. The conclusions remain unchanged.
[ { "created": "Mon, 26 Feb 2001 11:44:17 GMT", "version": "v1" }, { "created": "Tue, 27 Feb 2001 09:19:23 GMT", "version": "v2" }, { "created": "Mon, 19 Mar 2001 10:07:24 GMT", "version": "v3" } ]
2007-05-23
[ [ "Yndurain", "F. J.", "" ] ]
In a recent experimental paper reporting a precise measurement of the muon anomalous magnetic moment, Brown et al. claim disagreement of their result with evaluations based on the standard model. This claim is based on comparison with a single theoretical evaluation. It is pointed out that other equally legitimate theoretical evaluations exist in the literature, with which the new experimental figure is quite compatible. The claim of indications for new physics beyond the standard model does not appear justified. In this version we take into account corrections to one of the works quoted, we include a new discussion at the end, and also minor errors are corrected. The conclusions remain unchanged.
1705.02241
Antoni Szczurek
Marta Luszczak, Rafal Maciula, Antoni Szczurek and Izabela Babiarz
Single-diffractive production of dijets within the $k_t$-factorization approach
18 pages, 16 figures, 1 table
Phys. Rev. D 96, 054018 (2017)
10.1103/PhysRevD.96.054018
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss single-diffractive production of dijets. The cross section is calculated within the resolved pomeron picture, for the first time in the $k_t$-factorization approach, neglecting transverse momentum of the pomeron. We use Kimber-Martin-Ryskin unintegrated parton (gluon, quark, antiquark) distributions (UPDF) both in the proton as well as in the pomeron or subleading reggeon. The UPDFs are calculated based on conventional MMHT2014nlo PDFs in the proton and H1 collaboration diffractive PDFs used previously in the analysis of diffractive structure function and dijets at HERA. For comparison we present results of calculations performed within collinear-factorization approach. Our results remaind those obtained in the NLO approach. The calculation is (must be) supplemented by the so-called gap survival factor which may, in general, depend on kinematical variables. We try to describe the existing data from Tevatron and make detailed predictions for possible LHC measurements. Several differential distributions are calculated. The $\overline{E}_T$, $\overline{\eta}$ and $x_{\bar p}$ distributions are compared with the Tevatron data. A reasonable agreement is obtained for the first two distributions. The last one requires to introduce a gap survival factor which depends on kinematical variables. We discuss how the phenomenological dependence on one kinematical variable may influence dependence on other variables such as ${\overline E}_T$ and ${\overline \eta}$. Several distributions for the LHC are shown.
[ { "created": "Fri, 5 May 2017 14:46:20 GMT", "version": "v1" }, { "created": "Wed, 10 May 2017 12:46:22 GMT", "version": "v2" } ]
2017-09-27
[ [ "Luszczak", "Marta", "" ], [ "Maciula", "Rafal", "" ], [ "Szczurek", "Antoni", "" ], [ "Babiarz", "Izabela", "" ] ]
We discuss single-diffractive production of dijets. The cross section is calculated within the resolved pomeron picture, for the first time in the $k_t$-factorization approach, neglecting transverse momentum of the pomeron. We use Kimber-Martin-Ryskin unintegrated parton (gluon, quark, antiquark) distributions (UPDF) both in the proton as well as in the pomeron or subleading reggeon. The UPDFs are calculated based on conventional MMHT2014nlo PDFs in the proton and H1 collaboration diffractive PDFs used previously in the analysis of diffractive structure function and dijets at HERA. For comparison we present results of calculations performed within collinear-factorization approach. Our results remaind those obtained in the NLO approach. The calculation is (must be) supplemented by the so-called gap survival factor which may, in general, depend on kinematical variables. We try to describe the existing data from Tevatron and make detailed predictions for possible LHC measurements. Several differential distributions are calculated. The $\overline{E}_T$, $\overline{\eta}$ and $x_{\bar p}$ distributions are compared with the Tevatron data. A reasonable agreement is obtained for the first two distributions. The last one requires to introduce a gap survival factor which depends on kinematical variables. We discuss how the phenomenological dependence on one kinematical variable may influence dependence on other variables such as ${\overline E}_T$ and ${\overline \eta}$. Several distributions for the LHC are shown.
hep-ph/9212238
Alkofer
R. Alkofer and H. Reinhardt
The chiral anomaly and electromagnetic pion decay in effective quark models
6 pages, UNITUE-THEP-19/1992
null
null
null
hep-ph
null
Within renormalizable theories the triangle diagram correctly reproduces the lifetime of the neutral pion $\pi ^0$. However, effective relativistic quark models which contain a second scale besides the quark mass seem unable to give the correct value for this quantity. In the Instanton Liquid Model this second scale is the mean instanton radius, in the NJL model it is the cutoff. The role of the cutoff within a path integral derivation of the chiral anomaly is clarified and the importance of higher order terms contributing to the $\pi ^0$ decay width and other anomalous processes is pointed out.
[ { "created": "Tue, 8 Dec 1992 16:30:21 GMT", "version": "v1" } ]
2007-05-23
[ [ "Alkofer", "R.", "" ], [ "Reinhardt", "H.", "" ] ]
Within renormalizable theories the triangle diagram correctly reproduces the lifetime of the neutral pion $\pi ^0$. However, effective relativistic quark models which contain a second scale besides the quark mass seem unable to give the correct value for this quantity. In the Instanton Liquid Model this second scale is the mean instanton radius, in the NJL model it is the cutoff. The role of the cutoff within a path integral derivation of the chiral anomaly is clarified and the importance of higher order terms contributing to the $\pi ^0$ decay width and other anomalous processes is pointed out.
2208.09820
Amruta Mishra
Sourodeep De and Amruta Mishra
Open Charm mesons in magnetized nuclear matter -- effects of (inverse) magnetic catalysis
19 pages, 9 figures
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The in-medium masses of the open charm ($D$ and $\bar D$) mesons in magnetized isospin asymmetric nuclear matter are investigated within a chiral effective model, including the contributions of the Dirac sea (DS) to the self-energies of the nucleons. Within the model, the masses of these mesons are calculated from their interactions with the nucleons and the scalar ($\sigma\sim(\langle\bar u u\rangle+\langle \bar d d \rangle)$, $\zeta\sim\langle {\bar s}s\rangle$ and $\delta\sim(\langle{\bar u} u\rangle-\langle {\bar d} d\rangle)$) fields. The Dirac sea contributions are observed to lead to an enhancement (reduction) of the quark condensates with increase in magnetic field, an effect called `(inverse) magnetic catalysis'. These contributions are observed to appreciably modify the open charm meson masses calculated within the chiral effective model. In the presence of an external magnetic field, there is mixing of the pseudoscalar and the vector mesons (PV mixing), leading to as a drop (increase) in the mass of the pseudoscalar (longitudinal component of the vector) meson. The effects of the (inverse) magnetic catalysis, in addition to the PV mixing and Landau level contribtuions (for charged mesons) are observed to lead to significant modifications to the masses of the open charm mesons. These can modify the decay widths of the charmonium states to open charm mesons, e.g., $\psi(3770)\rightarrow D\bar D$, as well as $D^*\rightarrow D\pi$ (and $\bar {D^*}\rightarrow {\bar D}\pi$), which can affect the production of the open charm and charmonium states in ultra relativistic peripheral heavy ion collision experiments, where the created magnetic field is huge.
[ { "created": "Sun, 21 Aug 2022 06:51:25 GMT", "version": "v1" }, { "created": "Mon, 17 Oct 2022 16:00:16 GMT", "version": "v2" } ]
2023-03-17
[ [ "De", "Sourodeep", "" ], [ "Mishra", "Amruta", "" ] ]
The in-medium masses of the open charm ($D$ and $\bar D$) mesons in magnetized isospin asymmetric nuclear matter are investigated within a chiral effective model, including the contributions of the Dirac sea (DS) to the self-energies of the nucleons. Within the model, the masses of these mesons are calculated from their interactions with the nucleons and the scalar ($\sigma\sim(\langle\bar u u\rangle+\langle \bar d d \rangle)$, $\zeta\sim\langle {\bar s}s\rangle$ and $\delta\sim(\langle{\bar u} u\rangle-\langle {\bar d} d\rangle)$) fields. The Dirac sea contributions are observed to lead to an enhancement (reduction) of the quark condensates with increase in magnetic field, an effect called `(inverse) magnetic catalysis'. These contributions are observed to appreciably modify the open charm meson masses calculated within the chiral effective model. In the presence of an external magnetic field, there is mixing of the pseudoscalar and the vector mesons (PV mixing), leading to as a drop (increase) in the mass of the pseudoscalar (longitudinal component of the vector) meson. The effects of the (inverse) magnetic catalysis, in addition to the PV mixing and Landau level contribtuions (for charged mesons) are observed to lead to significant modifications to the masses of the open charm mesons. These can modify the decay widths of the charmonium states to open charm mesons, e.g., $\psi(3770)\rightarrow D\bar D$, as well as $D^*\rightarrow D\pi$ (and $\bar {D^*}\rightarrow {\bar D}\pi$), which can affect the production of the open charm and charmonium states in ultra relativistic peripheral heavy ion collision experiments, where the created magnetic field is huge.
1704.00259
Nilmani Mathur
M. Padmanath and Nilmani Mathur
Quantum Numbers of Recently Discovered $\Omega^{0}_{c}$ Baryons from Lattice QCD
Version accepted for publication in Physical Review Letters
Phys. Rev. Lett. 119, 042001 (2017)
10.1103/PhysRevLett.119.042001
TIFR/TH/17-12
hep-ph hep-ex hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the ground and excited state spectra of $\Omega^{0}_{c}$ baryons with spin up to 7/2 from lattice quantum chromodynamics with dynamical quark fields. Based on our lattice results, we predict the quantum numbers of five $\Omega^{0}_{c}$ baryons, which have recently been observed by the LHCb Collaboration. Our results strongly indicate that the observed states $\Omega_c(3000)^0$ and $\Omega_c(3050)^0$ have spin-parity $J^P = 1/2^{-}$, the states $\Omega_c(3066)^0$ and $\Omega_c(3090)^0$ have $J^P = 3/2^{-}$, whereas $\Omega_c(3119)^0$ is possibly a $5/2^{-}$ state.
[ { "created": "Sun, 2 Apr 2017 07:50:29 GMT", "version": "v1" }, { "created": "Wed, 26 Jul 2017 06:02:32 GMT", "version": "v2" } ]
2017-08-02
[ [ "Padmanath", "M.", "" ], [ "Mathur", "Nilmani", "" ] ]
We present the ground and excited state spectra of $\Omega^{0}_{c}$ baryons with spin up to 7/2 from lattice quantum chromodynamics with dynamical quark fields. Based on our lattice results, we predict the quantum numbers of five $\Omega^{0}_{c}$ baryons, which have recently been observed by the LHCb Collaboration. Our results strongly indicate that the observed states $\Omega_c(3000)^0$ and $\Omega_c(3050)^0$ have spin-parity $J^P = 1/2^{-}$, the states $\Omega_c(3066)^0$ and $\Omega_c(3090)^0$ have $J^P = 3/2^{-}$, whereas $\Omega_c(3119)^0$ is possibly a $5/2^{-}$ state.
2205.10576
Mogens Dam
Wolfgang Altmannshofer, Cecile Caillol, Mogens Dam, Stefania Xella, Yongchao Zhang
Charged Lepton Flavour Violation in Heavy Particle DEcays
White paper submitted to the Proceedings of the US Community Study on the Future of Particle Physics (Snowmass 2021)
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Charged lepton flavor violation is an unambiguous signature for New Physics. Here we present a summary of the theoretical and experimental status of the search for charged lepton flavor violation in heavy particle decays, in particular in the decays of the Z and Higgs bosons, and of the top quark. Decays of beyond-Standard-Model particles such as a Z' or an additional scalar particle are also discussed. Finally the prospects for such searches at proposed future electron-positron colliders are reviewed.
[ { "created": "Sat, 21 May 2022 12:03:17 GMT", "version": "v1" } ]
2022-05-24
[ [ "Altmannshofer", "Wolfgang", "" ], [ "Caillol", "Cecile", "" ], [ "Dam", "Mogens", "" ], [ "Xella", "Stefania", "" ], [ "Zhang", "Yongchao", "" ] ]
Charged lepton flavor violation is an unambiguous signature for New Physics. Here we present a summary of the theoretical and experimental status of the search for charged lepton flavor violation in heavy particle decays, in particular in the decays of the Z and Higgs bosons, and of the top quark. Decays of beyond-Standard-Model particles such as a Z' or an additional scalar particle are also discussed. Finally the prospects for such searches at proposed future electron-positron colliders are reviewed.
hep-ph/9909305
Igor Solovtsov
I.L. Solovtsov and D.V. Shirkov
Analytic Approach in Quantum Chromodynamics
30 pages, LaTeX with epsfig.sty, 11 PostScript figures
Theor.Math.Phys. 120 (1999) 1220-1244; Teor.Mat.Fiz. 120 (1999) 482-510
10.1007/BF02557245
JINR E2-99-244
hep-ph
null
We investigate a new ``renormalization invariant analytic formulation'' of calculations in quantum chromodynamics, where the renormalization group summation is correlated with the analyticity with respect to the square of the transferred momentum $Q^2$. The expressions for the invariant charge and matrix elements are then modified such that the unphysical singularities of the ghost pole type do not appear at all, being by construction compensated by additional nonperturbative contributions. Using the new scheme, we show that the results of calculations for a number of physical processes are stable with respect to higher-loop effects and the choice of the renormalization prescription. Having in mind applications of the new formulation to inelastic lepton-nucleon scattering processes, we analyze the corresponding structure functions starting from the general principles of the theory expressed by the Jost-Lehmann-Dyson integral representation. We use a nonstandard scaling variable that leads to modified moments of the structure functions possessing K\"all\'en-Lehmann analytic properties with respect to $Q^2$. We find the relation between these ``modified analytic moments'' and the operator product expansion.
[ { "created": "Thu, 9 Sep 1999 12:14:03 GMT", "version": "v1" } ]
2009-10-31
[ [ "Solovtsov", "I. L.", "" ], [ "Shirkov", "D. V.", "" ] ]
We investigate a new ``renormalization invariant analytic formulation'' of calculations in quantum chromodynamics, where the renormalization group summation is correlated with the analyticity with respect to the square of the transferred momentum $Q^2$. The expressions for the invariant charge and matrix elements are then modified such that the unphysical singularities of the ghost pole type do not appear at all, being by construction compensated by additional nonperturbative contributions. Using the new scheme, we show that the results of calculations for a number of physical processes are stable with respect to higher-loop effects and the choice of the renormalization prescription. Having in mind applications of the new formulation to inelastic lepton-nucleon scattering processes, we analyze the corresponding structure functions starting from the general principles of the theory expressed by the Jost-Lehmann-Dyson integral representation. We use a nonstandard scaling variable that leads to modified moments of the structure functions possessing K\"all\'en-Lehmann analytic properties with respect to $Q^2$. We find the relation between these ``modified analytic moments'' and the operator product expansion.
0801.4147
Marcus Bluhm
M. Bluhm (Forschungszentrum Dresden-Rossendorf), B. Kampfer (Forschungszentrum Dresden-Rossendorf & Dresden, Tech. U.)
Flavor Diagonal and Off-Diagonal Susceptibilities in a Quasiparticle Model of the Quark-Gluon Plasma
Jan 2008. 25 pp
Phys.Rev.D77:114016,2008
10.1103/PhysRevD.77.114016
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Taylor coefficients of flavor diagonal and off-diagonal susceptibilities as well as baryon number, isovector and electric charge susceptibilities are considered within a phenomenological quasiparticle model of the quark-gluon plasma and successfully compared with lattice QCD data for two degenerate quark flavors. These susceptibility coefficients represent sensible probes of baryon density effects in the equation of state. The baryon charge is carried, in our model, by quark-quasiparticle excitations for hard momenta.
[ { "created": "Sun, 27 Jan 2008 18:52:55 GMT", "version": "v1" }, { "created": "Tue, 8 Jul 2008 09:01:35 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bluhm", "M.", "", "Forschungszentrum Dresden-Rossendorf" ], [ "Kampfer", "B.", "", "Forschungszentrum Dresden-Rossendorf & Dresden, Tech. U." ] ]
The Taylor coefficients of flavor diagonal and off-diagonal susceptibilities as well as baryon number, isovector and electric charge susceptibilities are considered within a phenomenological quasiparticle model of the quark-gluon plasma and successfully compared with lattice QCD data for two degenerate quark flavors. These susceptibility coefficients represent sensible probes of baryon density effects in the equation of state. The baryon charge is carried, in our model, by quark-quasiparticle excitations for hard momenta.
0806.3259
Kuang-Ta Chao
Ce Meng, Kuang-Ta Chao
$\Upsilon(4S,5S)\to\Upsilon(1S)\eta$ transitions in the rescattering model and the new BaBar measurement
Version published in PRD, 5 pages, 1 figure
Phys.Rev.D78:074001,2008
10.1103/PhysRevD.78.074001
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $\eta$ transitions of $\Upsilon(4S,5S)$ into $\Upsilon(1S,2S)$ are studied in the rescattering model by considering the final state interactions above the $B\bar B$ threshold. The width of the $\eta$ transition of $\Upsilon(4S)$ into $\Upsilon(1S)$ is found to be larger than that of the dipion transition, and the ratio of $\Gamma(\Upsilon(4S)\to\Upsilon(1S)\eta)$ to $\Gamma(\Upsilon(4S)\to\Upsilon(1S)\pi^+\pi^-)$ is predicted to be $R_4=1.8{-}4.5$, which is about two orders of magnitude larger than the expectation of the conventional hadronic transition theory, and is supported by the new BaBar measurement. The widths of the $\eta$ transitions of $\Upsilon(5S)$ are found to be sensitive to the coupling constants $g_{\Upsilon(5S)B^{(*)}B^{(*)}}$ due to a large cancelation between contributions from the $B\bar{B}$, $B^*\bar{B}+c.c.$, and $B^*\bar{B}^*$ channels, and only a rough estimate $\Gamma(\Upsilon(5S)\to\Upsilon(1S,2S)\eta)=10{-}200$ KeV can be given. The widths of the $\eta'$ transitions of $\Upsilon(4S,5S)$ are also discussed, and they could be much smaller than that of the corresponding $\eta$ transitions mainly due to the tiny phase space.
[ { "created": "Thu, 19 Jun 2008 18:41:11 GMT", "version": "v1" }, { "created": "Mon, 13 Oct 2008 15:37:59 GMT", "version": "v2" } ]
2008-11-26
[ [ "Meng", "Ce", "" ], [ "Chao", "Kuang-Ta", "" ] ]
The $\eta$ transitions of $\Upsilon(4S,5S)$ into $\Upsilon(1S,2S)$ are studied in the rescattering model by considering the final state interactions above the $B\bar B$ threshold. The width of the $\eta$ transition of $\Upsilon(4S)$ into $\Upsilon(1S)$ is found to be larger than that of the dipion transition, and the ratio of $\Gamma(\Upsilon(4S)\to\Upsilon(1S)\eta)$ to $\Gamma(\Upsilon(4S)\to\Upsilon(1S)\pi^+\pi^-)$ is predicted to be $R_4=1.8{-}4.5$, which is about two orders of magnitude larger than the expectation of the conventional hadronic transition theory, and is supported by the new BaBar measurement. The widths of the $\eta$ transitions of $\Upsilon(5S)$ are found to be sensitive to the coupling constants $g_{\Upsilon(5S)B^{(*)}B^{(*)}}$ due to a large cancelation between contributions from the $B\bar{B}$, $B^*\bar{B}+c.c.$, and $B^*\bar{B}^*$ channels, and only a rough estimate $\Gamma(\Upsilon(5S)\to\Upsilon(1S,2S)\eta)=10{-}200$ KeV can be given. The widths of the $\eta'$ transitions of $\Upsilon(4S,5S)$ are also discussed, and they could be much smaller than that of the corresponding $\eta$ transitions mainly due to the tiny phase space.
2105.09693
Mart\'in Novoa-Brunet
S\'ebastien Descotes-Genon, Svjetlana Fajfer, Jernej F. Kamenik, Mart\'in Novoa-Brunet
Implications of $b\to s\ell^+\ell^-$ constraints on $b\to s\nu\bar\nu$ and $s\to d\nu\bar\nu$
Contribution to the 2021 EW session of the 55th Rencontres de Moriond
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the consequences of deviations from the Standard Model observed in $b\to s\mu\mu$ transitions for flavour-changing neutral-current processes involving down-type quarks and neutrinos, under generic assumptions concerning the structure of New Physics. We derive the relevant Wilson coefficients within an effective field theory approach respecting the SM gauge symmetry, including right-handed currents and assuming a flavour structure based on approximate $U(2)$ symmetry, and only SM-like light neutrinos. We discuss correlations among $B \to K^{(*)} \nu \bar \nu$ and $K\to \pi \nu \bar \nu$ branching ratios in the case of linear Minimal Flavour Violation and in a more general framework, highlighting in each case the role played by various New Physics scenarios proposed to explain $b\to s\mu\mu$ deviations. This talk is based on arXiv:2005.03734.
[ { "created": "Thu, 20 May 2021 12:08:57 GMT", "version": "v1" } ]
2021-05-21
[ [ "Descotes-Genon", "Sébastien", "" ], [ "Fajfer", "Svjetlana", "" ], [ "Kamenik", "Jernej F.", "" ], [ "Novoa-Brunet", "Martín", "" ] ]
We investigate the consequences of deviations from the Standard Model observed in $b\to s\mu\mu$ transitions for flavour-changing neutral-current processes involving down-type quarks and neutrinos, under generic assumptions concerning the structure of New Physics. We derive the relevant Wilson coefficients within an effective field theory approach respecting the SM gauge symmetry, including right-handed currents and assuming a flavour structure based on approximate $U(2)$ symmetry, and only SM-like light neutrinos. We discuss correlations among $B \to K^{(*)} \nu \bar \nu$ and $K\to \pi \nu \bar \nu$ branching ratios in the case of linear Minimal Flavour Violation and in a more general framework, highlighting in each case the role played by various New Physics scenarios proposed to explain $b\to s\mu\mu$ deviations. This talk is based on arXiv:2005.03734.
hep-ph/9611404
Leonid Glozman
L.Ya. Glozman
Baryons in chiral constituent quark model
10 pages, LaTeX (+PicTeX.sty) file, Invited talk given at the (i) International Conference "Quark Confinement and the Hadron Spectrum II (Como, Italy, June 26-29, 1996), (ii) CEBAF/INT Workshop on N* Physics (Seattle, USA, September 9-13, 1996)
null
null
UNIGRAZ-UTP 24-11-96
hep-ph nucl-th
null
Beyond the spontaneous chiral symmetry breaking scale light and strange baryons should be considered as systems of three constituent quarks with an effective confining interaction and a flavor-spin chiral interaction that is mediated by the octet of Goldstone bosons (pseudoscalar mesons) between the constituent quarks. One cannot exclude, however, the possibility that this flavor-spin interaction has an appreciable vector- and higher meson exchange component.
[ { "created": "Sun, 24 Nov 1996 15:18:51 GMT", "version": "v1" } ]
2007-05-23
[ [ "Glozman", "L. Ya.", "" ] ]
Beyond the spontaneous chiral symmetry breaking scale light and strange baryons should be considered as systems of three constituent quarks with an effective confining interaction and a flavor-spin chiral interaction that is mediated by the octet of Goldstone bosons (pseudoscalar mesons) between the constituent quarks. One cannot exclude, however, the possibility that this flavor-spin interaction has an appreciable vector- and higher meson exchange component.
1109.0020
Koji Hashimoto
Minoru Eto, Koji Hashimoto, Hideaki Iida, Takaaki Ishii, Yu Maezawa
Anomaly-induced charges in baryons
18 pages, 12 figures
null
10.1103/PhysRevD.85.114038
DAMTP-2011-53, RIKEN-MP-25, YGHP-11-44
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that quantum chiral anomaly of QCD in magnetic backgrounds induces a novel structure of electric charge inside baryons. To illustrate the anomaly effect, we employ the Skyrme model for baryons, with the anomaly-induced gauged Wess-Zumino term (\pi_0 + (multi-pion)) E_i B_i. Due to this term, the Skyrmions giving a local pion condensation ((\pi_0 + (multi-pion)) \neq 0) necessarily become a local charge source, in the background magnetic field B_i. We present detailed evaluation of the anomaly effects, and calculate the total induced charge, for various baryons in the magnetic field.
[ { "created": "Wed, 31 Aug 2011 20:08:00 GMT", "version": "v1" } ]
2013-05-30
[ [ "Eto", "Minoru", "" ], [ "Hashimoto", "Koji", "" ], [ "Iida", "Hideaki", "" ], [ "Ishii", "Takaaki", "" ], [ "Maezawa", "Yu", "" ] ]
We show that quantum chiral anomaly of QCD in magnetic backgrounds induces a novel structure of electric charge inside baryons. To illustrate the anomaly effect, we employ the Skyrme model for baryons, with the anomaly-induced gauged Wess-Zumino term (\pi_0 + (multi-pion)) E_i B_i. Due to this term, the Skyrmions giving a local pion condensation ((\pi_0 + (multi-pion)) \neq 0) necessarily become a local charge source, in the background magnetic field B_i. We present detailed evaluation of the anomaly effects, and calculate the total induced charge, for various baryons in the magnetic field.
1107.4614
Daniel Elbio Lopez
Javier Fidalgo, Daniel E. Lopez-Fogliani, Carlos Munoz, Roberto Ruiz de Austri
The Higgs sector of the munuSSM and collider physics
Final version to appear in JHEP. The discussion on signals at colliders, expanded. 33 pages, 8 figures and 9 tables
null
10.1007/JHEP10(2011)020
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $\mu\nu$SSM is a supersymmetric standard model that accounts for light neutrino masses and solves the $\mu$ problem of the MSSM by simply using right-handed neutrino superfields. Since this mechanism breaks R-parity, a peculiar structure for the mass matrices is generated. The neutral Higgses are mixed with the right- and left-handed sneutrinos producing 8$\times$8 neutral scalar mass matrices. We analyse the Higgs sector of the $\mu\nu$SSM in detail, with special emphasis in possible signals at colliders. After studying in general the decays of the Higges, we focus on those processes that are genuine of the $\mu\nu$SSM, and could serve to distinguish it from other supersymmetric models. In particular, we present viable benchmark points for LHC searches. For example, we find decays of a MSSM-like Higgs into two lightest neutralinos, with the latter decaying inside the detector leading to displaced vertices, and producing final states with 4 and 8 $b$-jets plus missing energy. Final states with leptons and missing energy are also found.
[ { "created": "Fri, 22 Jul 2011 20:08:20 GMT", "version": "v1" }, { "created": "Thu, 6 Oct 2011 18:17:53 GMT", "version": "v2" } ]
2015-05-28
[ [ "Fidalgo", "Javier", "" ], [ "Lopez-Fogliani", "Daniel E.", "" ], [ "Munoz", "Carlos", "" ], [ "de Austri", "Roberto Ruiz", "" ] ]
The $\mu\nu$SSM is a supersymmetric standard model that accounts for light neutrino masses and solves the $\mu$ problem of the MSSM by simply using right-handed neutrino superfields. Since this mechanism breaks R-parity, a peculiar structure for the mass matrices is generated. The neutral Higgses are mixed with the right- and left-handed sneutrinos producing 8$\times$8 neutral scalar mass matrices. We analyse the Higgs sector of the $\mu\nu$SSM in detail, with special emphasis in possible signals at colliders. After studying in general the decays of the Higges, we focus on those processes that are genuine of the $\mu\nu$SSM, and could serve to distinguish it from other supersymmetric models. In particular, we present viable benchmark points for LHC searches. For example, we find decays of a MSSM-like Higgs into two lightest neutralinos, with the latter decaying inside the detector leading to displaced vertices, and producing final states with 4 and 8 $b$-jets plus missing energy. Final states with leptons and missing energy are also found.
1110.2236
Sarira Sahu
Sarira Sahu, Bing Zhang
Superluminal Neutrinos in a Pseudoscalar Potential
3 pages
null
null
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The superluminal propagation of neutrinos observed by OPERA collaboration can be interpreted as neutrinos traveling in a pseudoscalar potential which may be generated by a medium. The OPERA differential arrival time data set a constraint on the form of the pseudoscalar potential.
[ { "created": "Tue, 11 Oct 2011 00:07:22 GMT", "version": "v1" } ]
2011-10-12
[ [ "Sahu", "Sarira", "" ], [ "Zhang", "Bing", "" ] ]
The superluminal propagation of neutrinos observed by OPERA collaboration can be interpreted as neutrinos traveling in a pseudoscalar potential which may be generated by a medium. The OPERA differential arrival time data set a constraint on the form of the pseudoscalar potential.
1809.02973
Mikhail Ivanov
Mikhail A. Ivanov
Dynamical picture for the exotic XYZ states
7 pages, 4 figures, some references added
null
10.1051/epjconf/201819200042
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a dynamical approach for description of the multi-quark states that is based on an effective interaction Lagrangian describing the coupling of hadrons to their constituent quarks. First, we explore the consequences of treating the $X(3872)$ meson as a tetraquark bound state. We calculate the decay widths of the observed channels and conclude that for reasonable values of the size parameter of the $X(3872)$ one finds consistency with the available experimental data. Then we have critically checked the tetraquark picture for the $Z_c(3900)$ state by analyzing its strong decays. We found that $Z_c(3900)$ has a much more stronger coupling to $DD^\ast$ than to $J/\psi\pi$ that is in discord with experiment. As an alternative we have employed a molecular-type four-quark current to describe the decays of the $Z_c(3900)$ state as the charged particle in the isotriplet. We found that a molecular-type current gives the values of the above decays in accordance with the experimental observation. By using molecular-type four-quark currents for the recently observed resonances $Z_b(10610)$ and $Z_b(10650)$, we have calculated their two-body decay rates into a bottomonium state plus a light meson as well as into B-meson pairs.
[ { "created": "Sun, 9 Sep 2018 13:45:27 GMT", "version": "v1" }, { "created": "Tue, 25 Sep 2018 10:22:18 GMT", "version": "v2" } ]
2018-12-05
[ [ "Ivanov", "Mikhail A.", "" ] ]
We present a dynamical approach for description of the multi-quark states that is based on an effective interaction Lagrangian describing the coupling of hadrons to their constituent quarks. First, we explore the consequences of treating the $X(3872)$ meson as a tetraquark bound state. We calculate the decay widths of the observed channels and conclude that for reasonable values of the size parameter of the $X(3872)$ one finds consistency with the available experimental data. Then we have critically checked the tetraquark picture for the $Z_c(3900)$ state by analyzing its strong decays. We found that $Z_c(3900)$ has a much more stronger coupling to $DD^\ast$ than to $J/\psi\pi$ that is in discord with experiment. As an alternative we have employed a molecular-type four-quark current to describe the decays of the $Z_c(3900)$ state as the charged particle in the isotriplet. We found that a molecular-type current gives the values of the above decays in accordance with the experimental observation. By using molecular-type four-quark currents for the recently observed resonances $Z_b(10610)$ and $Z_b(10650)$, we have calculated their two-body decay rates into a bottomonium state plus a light meson as well as into B-meson pairs.
1301.5855
Ruth Van de Water
A. Bazavov, C. Bernard, C. DeTar, J. Foley, W. Freeman, Steven Gottlieb, U. M. Heller, J. E. Hetrick, J. Kim, J. Laiho, L. Levkova, M. Lightman, J. Osborn, S. Qiu, R. L. Sugar, D. Toussaint, R. S. Van de Water, R. Zhou
Leptonic decay-constant ratio f_{K^+}/f_{pi^+} from lattice QCD with physical light quarks
6 pages, 1 table, 2 figures; v3: result for f_{K^+}/f_{pi^+} updated to include additional data; typo in some values of L in Table 1 corrected; typo in sign of 1-|V_{ud}|^2-|V_{us}|^2-|V_{ub}|^2 corrected; version to be published in Phys. Rev. Lett
null
10.1103/PhysRevLett.110.172003
null
hep-ph hep-lat
http://creativecommons.org/licenses/publicdomain/
A calculation of the ratio of leptonic decay constants f_{K^+}/f_{\pi^+} makes possible a precise determination of the ratio of CKM matrix elements |V_{us}|/|V_{ud}| in the Standard Model, and places a stringent constraint on the scale of new physics that would lead to deviations from unitarity in the first row of the CKM matrix. We compute f_{K^+}/f_{\pi^+} numerically in unquenched lattice QCD using gauge-field ensembles recently generated that include four flavors of dynamical quarks: up, down, strange, and charm. We analyze data at four lattice spacings a ~ 0.06, 0.09, 0.12, and 0.15 fm with simulated pion masses down to the physical value 135 MeV. We obtain f_{K^+}/f_{\pi^+} = 1.1947(26)(37), where the errors are statistical and total systematic, respectively. This is our first physics result from our N_f = 2+1+1 ensembles, and the first calculation of f_{K^+}/f_{\pi^+} from lattice-QCD simulations at the physical point. Our result is the most precise lattice-QCD determination of f_{K^+}/f_{\pi^+}, with an error comparable to the current world average. When combined with experimental measurements of the leptonic branching fractions, it leads to a precise determination of |V_{us}|/|V_{ud}| = 0.2309(9)(4) where the errors are theoretical and experimental, respectively.
[ { "created": "Thu, 24 Jan 2013 18:18:27 GMT", "version": "v1" }, { "created": "Fri, 25 Jan 2013 19:04:54 GMT", "version": "v2" }, { "created": "Tue, 23 Apr 2013 17:50:24 GMT", "version": "v3" } ]
2013-05-01
[ [ "Bazavov", "A.", "" ], [ "Bernard", "C.", "" ], [ "DeTar", "C.", "" ], [ "Foley", "J.", "" ], [ "Freeman", "W.", "" ], [ "Gottlieb", "Steven", "" ], [ "Heller", "U. M.", "" ], [ "Hetrick", "J. E.", "" ], [ "Kim", "J.", "" ], [ "Laiho", "J.", "" ], [ "Levkova", "L.", "" ], [ "Lightman", "M.", "" ], [ "Osborn", "J.", "" ], [ "Qiu", "S.", "" ], [ "Sugar", "R. L.", "" ], [ "Toussaint", "D.", "" ], [ "Van de Water", "R. S.", "" ], [ "Zhou", "R.", "" ] ]
A calculation of the ratio of leptonic decay constants f_{K^+}/f_{\pi^+} makes possible a precise determination of the ratio of CKM matrix elements |V_{us}|/|V_{ud}| in the Standard Model, and places a stringent constraint on the scale of new physics that would lead to deviations from unitarity in the first row of the CKM matrix. We compute f_{K^+}/f_{\pi^+} numerically in unquenched lattice QCD using gauge-field ensembles recently generated that include four flavors of dynamical quarks: up, down, strange, and charm. We analyze data at four lattice spacings a ~ 0.06, 0.09, 0.12, and 0.15 fm with simulated pion masses down to the physical value 135 MeV. We obtain f_{K^+}/f_{\pi^+} = 1.1947(26)(37), where the errors are statistical and total systematic, respectively. This is our first physics result from our N_f = 2+1+1 ensembles, and the first calculation of f_{K^+}/f_{\pi^+} from lattice-QCD simulations at the physical point. Our result is the most precise lattice-QCD determination of f_{K^+}/f_{\pi^+}, with an error comparable to the current world average. When combined with experimental measurements of the leptonic branching fractions, it leads to a precise determination of |V_{us}|/|V_{ud}| = 0.2309(9)(4) where the errors are theoretical and experimental, respectively.
1704.06322
Ivo De Medeiros Varzielas
Ivo de Medeiros Varzielas, Stephen F. King, Christoph Luhn, Thomas Neder
Minima of multi-Higgs potentials with triplets of $\Delta(3n^2)$ and $\Delta(6n^2)$
15 pages
null
10.1016/j.physletb.2017.11.005
QFET-2017-05, SI-HEP-2017-06
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyse the minima of scalar potentials for multi-Higgs models where the scalars are arranged as either one triplet or two triplets of the discrete symmetries $A_4$, $S_4$, $\Delta(27)$, $\Delta(54)$, as well as $\Delta(3n^2)$ and $\Delta(6n^2)$ with $n>3$. The results should be useful for both multi-Higgs models involving electroweak doublets and multi-flavon models involving electroweak singlets, where in both cases the fields transform as triplets under some non-Abelian discrete symmetry.
[ { "created": "Thu, 20 Apr 2017 20:06:16 GMT", "version": "v1" } ]
2017-12-06
[ [ "Varzielas", "Ivo de Medeiros", "" ], [ "King", "Stephen F.", "" ], [ "Luhn", "Christoph", "" ], [ "Neder", "Thomas", "" ] ]
We analyse the minima of scalar potentials for multi-Higgs models where the scalars are arranged as either one triplet or two triplets of the discrete symmetries $A_4$, $S_4$, $\Delta(27)$, $\Delta(54)$, as well as $\Delta(3n^2)$ and $\Delta(6n^2)$ with $n>3$. The results should be useful for both multi-Higgs models involving electroweak doublets and multi-flavon models involving electroweak singlets, where in both cases the fields transform as triplets under some non-Abelian discrete symmetry.
1312.2290
Ma Yong-Liang
Yong-Liang Ma, Masayasu Harada, Hyun Kyu Lee, Yongseok Oh, Mannque Rho
Skyrmions, half-skyrmions and nucleon mass in dense baryonic matter
Contribution to the Workshop on Hadron Nuclear Physics (HNP2013), 18-22 Jul. 2013, Zhangjiajie, China
null
10.1142/S2010194514602385
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the hadron properties in dense baryonic matter in a unified way by using a Skyrme model constructed with an effective Lagrangian which includes the $\rho$ and $\omega$ vector mesons as hidden gauge bosons and is valid up to $O(p^4)$ in chiral expansion including the homogeneous Wess-Zumino terms. With the two input values of pion decay constant and the lowest lying vector meson mass which can be fixed in free space, all the other low energy constants in the effective Lagrangian are determined by their master formulas derived from holographic QCD models, which allows us to study the baryonic matter properties with no additional free parameters and thus without ambiguities. We find that the $\omega$ field that figures in the homogeneous Wess-Zumino term plays a crucial role in the skyrmion structure and its matter properties. The most striking and intriguing observation is that the pion decay constant that smoothly drops with increasing density in the Skyrmion phase stops decreasing at $n_{1/2}^{}$ at which the skyrmions in medium fractionize into half-skyrmions and remains nearly constant in the half-skyrmion phase. In accordance with the large $N_c$ consideration, the baryon mass also stays non-scaling in the half-skyrmion phase. This feature is supported by the nuclear effective field theory with the parameters of the Lagrangian scaling modified at the skyrmion--half-skyrmion phase transition. Our exploration also uncovers the crucial role of the $\omega$ meson in multi-baryon systems as well as in the structure of a single skyrmion.
[ { "created": "Mon, 9 Dec 2013 01:22:07 GMT", "version": "v1" } ]
2015-06-18
[ [ "Ma", "Yong-Liang", "" ], [ "Harada", "Masayasu", "" ], [ "Lee", "Hyun Kyu", "" ], [ "Oh", "Yongseok", "" ], [ "Rho", "Mannque", "" ] ]
We explore the hadron properties in dense baryonic matter in a unified way by using a Skyrme model constructed with an effective Lagrangian which includes the $\rho$ and $\omega$ vector mesons as hidden gauge bosons and is valid up to $O(p^4)$ in chiral expansion including the homogeneous Wess-Zumino terms. With the two input values of pion decay constant and the lowest lying vector meson mass which can be fixed in free space, all the other low energy constants in the effective Lagrangian are determined by their master formulas derived from holographic QCD models, which allows us to study the baryonic matter properties with no additional free parameters and thus without ambiguities. We find that the $\omega$ field that figures in the homogeneous Wess-Zumino term plays a crucial role in the skyrmion structure and its matter properties. The most striking and intriguing observation is that the pion decay constant that smoothly drops with increasing density in the Skyrmion phase stops decreasing at $n_{1/2}^{}$ at which the skyrmions in medium fractionize into half-skyrmions and remains nearly constant in the half-skyrmion phase. In accordance with the large $N_c$ consideration, the baryon mass also stays non-scaling in the half-skyrmion phase. This feature is supported by the nuclear effective field theory with the parameters of the Lagrangian scaling modified at the skyrmion--half-skyrmion phase transition. Our exploration also uncovers the crucial role of the $\omega$ meson in multi-baryon systems as well as in the structure of a single skyrmion.
2307.11872
Antonios Kyriazis
A.Kyriazis
Dilute axion stars converting to photons in the Milky Way's magnetic field
null
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this paper we examine the possibility of dilute axion stars converting to photons in the weak, large-scale magnetic field of the Milky Way and show that they can resonate with the surrounding plasma and produce a sizable signal. We consider two possibilities for the plasma: free electrons and HII regions. In the former case, we argue that the frequency of the photons will be too small to be observed even by space-based radio telescopes. In the latter case, their frequency is larger, safely above the solar wind cut-off. We provide an estimate of the flux as a function of the decay constant and show that for $f_{a} < 5 \times 10^{11} \text{GeV}$, the signal will be above the radio emission of the solar system's planets and it could potentially be detected by the NCLE instrument which is on board the Chang'e-4 spacecraft. Finally, we calculate the time scale of decay of the axion star and demonstrate that back-reaction can be neglected for all physically interesting values of the decay constant, while the minimum time scale of decay is in the order of a few hours.
[ { "created": "Fri, 21 Jul 2023 19:24:18 GMT", "version": "v1" }, { "created": "Wed, 26 Jul 2023 22:18:16 GMT", "version": "v2" }, { "created": "Sun, 17 Sep 2023 20:47:08 GMT", "version": "v3" } ]
2023-09-19
[ [ "Kyriazis", "A.", "" ] ]
In this paper we examine the possibility of dilute axion stars converting to photons in the weak, large-scale magnetic field of the Milky Way and show that they can resonate with the surrounding plasma and produce a sizable signal. We consider two possibilities for the plasma: free electrons and HII regions. In the former case, we argue that the frequency of the photons will be too small to be observed even by space-based radio telescopes. In the latter case, their frequency is larger, safely above the solar wind cut-off. We provide an estimate of the flux as a function of the decay constant and show that for $f_{a} < 5 \times 10^{11} \text{GeV}$, the signal will be above the radio emission of the solar system's planets and it could potentially be detected by the NCLE instrument which is on board the Chang'e-4 spacecraft. Finally, we calculate the time scale of decay of the axion star and demonstrate that back-reaction can be neglected for all physically interesting values of the decay constant, while the minimum time scale of decay is in the order of a few hours.
1612.05848
Wei Dai
Wei Dai and Ben-Wei Zhang
Productions of $\eta$, $\rho^0$ and $\phi$ at large transverse momentum in Heavy ion Collisions
4 pages, 5 figures, proceedings for the Hard Probe 2016 parallel talk
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The suppression of the productions of the $\eta$ meson in relativistic heavy-ion collisions and its ratio of $\eta/\pi^0$ are computed theoretically in the framework of the perturbative QCD(pQCD) to confront the experimental data which matches well. We explore how the hadron production ratios as$\eta/\pi^0$ would further disclose the informations of the production suppressions due to the energy loss of the energetic jet that propagating though the QGP medium. Also, we present our further studies on vector mesons such as $\rho^0$ and $\phi$ within the same framework. The theoretical predictions based on pQCD are thus firstly given which give a decent description on the experimental measurements. It paved the way to the uniformly understanding of the strong suppression of single hadron productions at large transverse momentum which is a convincing evidence of the jet quenching effect.
[ { "created": "Sun, 18 Dec 2016 03:04:36 GMT", "version": "v1" } ]
2016-12-20
[ [ "Dai", "Wei", "" ], [ "Zhang", "Ben-Wei", "" ] ]
The suppression of the productions of the $\eta$ meson in relativistic heavy-ion collisions and its ratio of $\eta/\pi^0$ are computed theoretically in the framework of the perturbative QCD(pQCD) to confront the experimental data which matches well. We explore how the hadron production ratios as$\eta/\pi^0$ would further disclose the informations of the production suppressions due to the energy loss of the energetic jet that propagating though the QGP medium. Also, we present our further studies on vector mesons such as $\rho^0$ and $\phi$ within the same framework. The theoretical predictions based on pQCD are thus firstly given which give a decent description on the experimental measurements. It paved the way to the uniformly understanding of the strong suppression of single hadron productions at large transverse momentum which is a convincing evidence of the jet quenching effect.
0804.4471
Chee Sheng Fong
Chee Sheng Fong and M.C.Gonzalez-Garcia
Flavoured Soft Leptogenesis
20 pages, 5 figures. Version accepted in JHEP. Results unchanged
null
10.1088/1126-6708/2008/06/076
YITP-SB-08-18
hep-ph astro-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the impact of flavour in ``soft leptogenesis'' (leptogenesis induced by soft supersymmetry breaking terms). We address the question of how flavour effects can affect the region of parameters in which successful soft leptogenesis induced by CP violation in the right-handed sneutrino mixing is possible. We find that for decays which occur in the intermediate to strong washout regimes for all flavours, the produced total $B-L$ asymmetry can be up to a factor ${\cal O}(30)$ larger than the one predicted with flavour effects being neglected. This enhancement, permits slightly larger values of the required lepton violating soft bilinear term.
[ { "created": "Tue, 29 Apr 2008 15:28:27 GMT", "version": "v1" }, { "created": "Mon, 16 Jun 2008 17:56:04 GMT", "version": "v2" } ]
2009-11-13
[ [ "Fong", "Chee Sheng", "" ], [ "Gonzalez-Garcia", "M. C.", "" ] ]
We study the impact of flavour in ``soft leptogenesis'' (leptogenesis induced by soft supersymmetry breaking terms). We address the question of how flavour effects can affect the region of parameters in which successful soft leptogenesis induced by CP violation in the right-handed sneutrino mixing is possible. We find that for decays which occur in the intermediate to strong washout regimes for all flavours, the produced total $B-L$ asymmetry can be up to a factor ${\cal O}(30)$ larger than the one predicted with flavour effects being neglected. This enhancement, permits slightly larger values of the required lepton violating soft bilinear term.
hep-ph/0412247
Ghela Devidze G.
Ghela G Devidze (HEPI TSU), Akaki G Liparteliani (HEPI TSU)
Large Extra Dimensions
5 pages, Talk presented at the German-Caucasus School and Workshop on Hadron Physics (2004, Tbilisi)
null
null
null
hep-ph
null
The modern status of large extra dimensional (LED) approaches, highlights of their manifestation and short prehistory are discussed in this paper.
[ { "created": "Fri, 17 Dec 2004 11:04:24 GMT", "version": "v1" }, { "created": "Wed, 22 Dec 2004 10:09:51 GMT", "version": "v2" } ]
2007-05-23
[ [ "Devidze", "Ghela G", "", "HEPI TSU" ], [ "Liparteliani", "Akaki G", "", "HEPI TSU" ] ]
The modern status of large extra dimensional (LED) approaches, highlights of their manifestation and short prehistory are discussed in this paper.
1811.01961
Teng Ma
Csaba Cs\'aki, Felipe Ferreira De Freitas, Li Huang, Teng Ma, Maxim Perelstein, Jing Shu
Naturalness Sum Rules and Their Collider Tests
26 pages +9 appendices
null
10.1007/JHEP05(2019)132
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the most general sum rules reflecting the cancellation of ultraviolet divergences in the Higgs potential in weakly-coupled, natural extensions of the Standard Model. There is a separate sum rule for the cancellation of the quadratic and logarithmic divergences, and their forms depend on whether the divergences are canceled by same-spin or opposite-spin partners. These sum rules can be applied to mass eigenstates and conveniently used for direct collider tests of naturalness. We study in detail the feasibility of testing these sum rules in the top sector at a future $100\TeV$ proton collider within two benchmark models, the Little Higgs (LH) and the Maximally Symmetric Composite Higgs (MSCH). We show how the two ingredients of the sum rules, the top partner masses and their Yukawa couplings to the Higgs, can be measured with sufficient accuracy to provide a highly non-trivial quantitative test of the sum rules. In particular, we study observables sensitive to the sign of the top partner Yukawa, which is crucial for verifying the sum rules but is notoriously difficult to measure. We demonstrate that in the benchmark models under study, a statistically significant discrimination between the two possible signs of each Yukawa will be feasible with a 30 ab$^{-1}$ data set at $100\TeV$.
[ { "created": "Mon, 5 Nov 2018 19:00:03 GMT", "version": "v1" }, { "created": "Wed, 7 Nov 2018 14:17:04 GMT", "version": "v2" } ]
2019-06-26
[ [ "Csáki", "Csaba", "" ], [ "De Freitas", "Felipe Ferreira", "" ], [ "Huang", "Li", "" ], [ "Ma", "Teng", "" ], [ "Perelstein", "Maxim", "" ], [ "Shu", "Jing", "" ] ]
We present the most general sum rules reflecting the cancellation of ultraviolet divergences in the Higgs potential in weakly-coupled, natural extensions of the Standard Model. There is a separate sum rule for the cancellation of the quadratic and logarithmic divergences, and their forms depend on whether the divergences are canceled by same-spin or opposite-spin partners. These sum rules can be applied to mass eigenstates and conveniently used for direct collider tests of naturalness. We study in detail the feasibility of testing these sum rules in the top sector at a future $100\TeV$ proton collider within two benchmark models, the Little Higgs (LH) and the Maximally Symmetric Composite Higgs (MSCH). We show how the two ingredients of the sum rules, the top partner masses and their Yukawa couplings to the Higgs, can be measured with sufficient accuracy to provide a highly non-trivial quantitative test of the sum rules. In particular, we study observables sensitive to the sign of the top partner Yukawa, which is crucial for verifying the sum rules but is notoriously difficult to measure. We demonstrate that in the benchmark models under study, a statistically significant discrimination between the two possible signs of each Yukawa will be feasible with a 30 ab$^{-1}$ data set at $100\TeV$.
hep-ph/0606224
Norma Mankoc Borstnik
A. Borstnik Bracic, M. Breskvar, D. Lukman, N.S. Mankoc Borstnik
A new understanding of fermion masses from the unified theory of spins and charges
14 pages, revtex
null
null
null
hep-ph
null
In this letter we try to answer those of the open questions of the Standard model which concern the appearance of families, mass protection mechanism and the Yukawa couplings - by using the approach (proposed by one of us), which suggests a new way beyond the Standard model. The approach has in the starting action for fermions, which carry in d(=1 +13)-dimensional space only the spin (two kinds of the spin) and interact with only spin connection and vielbein fields, the term manifesting as a mass term in d=1+3. (After making several approximations and assumptions) we connect free parameters of the approach with the experimental data and investigate a possibility that the fourth family appears at low enough energies to be observable in the new generation of accelerators.
[ { "created": "Wed, 21 Jun 2006 10:51:21 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bracic", "A. Borstnik", "" ], [ "Breskvar", "M.", "" ], [ "Lukman", "D.", "" ], [ "Borstnik", "N. S. Mankoc", "" ] ]
In this letter we try to answer those of the open questions of the Standard model which concern the appearance of families, mass protection mechanism and the Yukawa couplings - by using the approach (proposed by one of us), which suggests a new way beyond the Standard model. The approach has in the starting action for fermions, which carry in d(=1 +13)-dimensional space only the spin (two kinds of the spin) and interact with only spin connection and vielbein fields, the term manifesting as a mass term in d=1+3. (After making several approximations and assumptions) we connect free parameters of the approach with the experimental data and investigate a possibility that the fourth family appears at low enough energies to be observable in the new generation of accelerators.
hep-ph/0209374
Ed Berger
Edmond L Berger
Light Bottom Squark Phenomenology
3 pages, latex, no figures, uses espcrc2.sty style file. Paper to be published in the Proceedings of the 31st International Conference on High Energy Physics (ICHEP02), Amsterdam, July 24 - 31, 2002
null
10.1016/S0920-5632(03)90664-5
ANL-HEP-CP-02-085
hep-ph hep-ex
null
Agreement of theoretical calculations with the observed production rate of bottom quarks at hadron colliders is improved by the introduction of a contribution from pair-production of light gluinos, of mass 12 to 16 GeV, having two-body decays into bottom quarks and light bottom squarks with mass $\simeq 2$ to 5.5 GeV. Predictions are made for hadronic and radiative decays of the Upsilon states. In the limit of large $\tan\beta$, the dominant decay mode of the light scalar Higgs boson is into a pair of light bottom squarks that materialize as jets of hadrons.
[ { "created": "Mon, 30 Sep 2002 16:29:03 GMT", "version": "v1" } ]
2009-11-07
[ [ "Berger", "Edmond L", "" ] ]
Agreement of theoretical calculations with the observed production rate of bottom quarks at hadron colliders is improved by the introduction of a contribution from pair-production of light gluinos, of mass 12 to 16 GeV, having two-body decays into bottom quarks and light bottom squarks with mass $\simeq 2$ to 5.5 GeV. Predictions are made for hadronic and radiative decays of the Upsilon states. In the limit of large $\tan\beta$, the dominant decay mode of the light scalar Higgs boson is into a pair of light bottom squarks that materialize as jets of hadrons.
1308.1077
Felix Yu
Felix Yu
Di-jet resonances at future hadron colliders: A Snowmass whitepaper
4 pages, 4 figures
null
null
FERMILAB-CONF-13-304-T
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I investigate the sensitivity of future hadron colliders to di-jet resonances arising from Z' or coloron models. The projected discovery potential and exclusion limits for these resonances is presented in the coupling vs. mass plane, which highlights both the increased mass reach from higher energy machines as well as the improved coupling sensivity from larger luminosity.
[ { "created": "Mon, 5 Aug 2013 19:27:20 GMT", "version": "v1" } ]
2013-08-06
[ [ "Yu", "Felix", "" ] ]
I investigate the sensitivity of future hadron colliders to di-jet resonances arising from Z' or coloron models. The projected discovery potential and exclusion limits for these resonances is presented in the coupling vs. mass plane, which highlights both the increased mass reach from higher energy machines as well as the improved coupling sensivity from larger luminosity.
0809.2917
Aleksander Filip Zarnecki
Aleksander Filip \.Zarnecki
Leptoquarks and Contact Interactions at LeHC
4 pages, 4 figures; Prepared for XVI International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2008)
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The sensitivity of LeHC to different models of "new physics" has been studied, both for the resonance production and in the contact interaction approximation. Expected limits are compared for different running scenarios. Direct leptoquark production can be studied for masses up to about 2 TeV. For contact interaction models scales up to about 70 TeV can be explored. Significant improvement of existing limits is also expected for models with large extra dimensions. Effective Plank mass scales up to about 5.4 TeV can be probed. LeHC will be sensitive to the quark substructure of the order of 1E-19 m.
[ { "created": "Wed, 17 Sep 2008 12:16:45 GMT", "version": "v1" } ]
2008-09-18
[ [ "Żarnecki", "Aleksander Filip", "" ] ]
The sensitivity of LeHC to different models of "new physics" has been studied, both for the resonance production and in the contact interaction approximation. Expected limits are compared for different running scenarios. Direct leptoquark production can be studied for masses up to about 2 TeV. For contact interaction models scales up to about 70 TeV can be explored. Significant improvement of existing limits is also expected for models with large extra dimensions. Effective Plank mass scales up to about 5.4 TeV can be probed. LeHC will be sensitive to the quark substructure of the order of 1E-19 m.
2205.00468
Wei-Jie Fu
Wei-jie Fu
QCD at finite temperature and density within the fRG approach: An overview
68 pages, 59 figures, 3 tables
null
10.1088/1572-9494/ac86be
null
hep-ph nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
In this paper we present an overview on recent progress in studies of QCD at finite temperature and densities within the functional renormalization group (fRG) approach. The fRG is a nonperturbative continuum field approach, in which quantum, thermal and density fluctuations are integrated in successively with the evolution of the renormalization group (RG) scale. The fRG results for the QCD phase structure and the location of the critical end point (CEP), the QCD equation of state (EoS), the magnetic EoS, baryon number fluctuations confronted with recent experimental measurements, various critical exponents, spectral functions in the critical region, the dynamical critical exponent, etc., are presented. Recent estimates of the location of the CEP from first-principle QCD calculations within fRG and Dyson-Schwinger Equations, which passes through lattice benchmark tests at small baryon chemical potentials, converge in a rather small region at baryon chemical potentials of about 600 MeV. A region of inhomogeneous instability indicated by a negative wave function renormalization is found with $\mu_B\gtrsim 420$ MeV. It is found that the non-monotonic dependence of the kurtosis of the net-proton number distributions on the beam collision energy observed in experiments, could arise from the increasingly sharp crossover in the regime of low collision energy.
[ { "created": "Sun, 1 May 2022 13:51:31 GMT", "version": "v1" } ]
2022-09-28
[ [ "Fu", "Wei-jie", "" ] ]
In this paper we present an overview on recent progress in studies of QCD at finite temperature and densities within the functional renormalization group (fRG) approach. The fRG is a nonperturbative continuum field approach, in which quantum, thermal and density fluctuations are integrated in successively with the evolution of the renormalization group (RG) scale. The fRG results for the QCD phase structure and the location of the critical end point (CEP), the QCD equation of state (EoS), the magnetic EoS, baryon number fluctuations confronted with recent experimental measurements, various critical exponents, spectral functions in the critical region, the dynamical critical exponent, etc., are presented. Recent estimates of the location of the CEP from first-principle QCD calculations within fRG and Dyson-Schwinger Equations, which passes through lattice benchmark tests at small baryon chemical potentials, converge in a rather small region at baryon chemical potentials of about 600 MeV. A region of inhomogeneous instability indicated by a negative wave function renormalization is found with $\mu_B\gtrsim 420$ MeV. It is found that the non-monotonic dependence of the kurtosis of the net-proton number distributions on the beam collision energy observed in experiments, could arise from the increasingly sharp crossover in the regime of low collision energy.
0902.3947
Pedro Jimenez-Delgado
Pedro Jim\'enez Delgado
Dynamical Parton Distributions of the Nucleon up to NNLO of QCD
Ph.D. Thesis, 98 pages
null
10.1016/j.nuclphysbps.2008.12.012
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A new generation of (unpolarized) dynamical parton distribution functions of the nucleon is determined. After introducing basic elements of perturbative QCD, the dynamical model is discussed and compared with the approach to parton distributions used by most other groups ("standard"). Parton distributions sets (with uncertainties) at different orders (LO, NLO, NNLO), using different factorization schemes (\overline{MS}, DIS) and different treatments of heavy quark masses (FFNS, VFNS) are extracted and compared. The astrophysical implications of the dynamical predictions are outlined before focusing on collider phenomenology. There, the relevance and perturbative stability of the longitudinal structure function of the nucleon is studied, and the role of heavy quark flavors in high-energy colliders is analyzed. In addition, it is shown how isospin violations in the nucleon help to explain the so-called "NuTeV anomaly".
[ { "created": "Mon, 23 Feb 2009 19:12:29 GMT", "version": "v1" } ]
2016-09-08
[ [ "Delgado", "Pedro Jiménez", "" ] ]
A new generation of (unpolarized) dynamical parton distribution functions of the nucleon is determined. After introducing basic elements of perturbative QCD, the dynamical model is discussed and compared with the approach to parton distributions used by most other groups ("standard"). Parton distributions sets (with uncertainties) at different orders (LO, NLO, NNLO), using different factorization schemes (\overline{MS}, DIS) and different treatments of heavy quark masses (FFNS, VFNS) are extracted and compared. The astrophysical implications of the dynamical predictions are outlined before focusing on collider phenomenology. There, the relevance and perturbative stability of the longitudinal structure function of the nucleon is studied, and the role of heavy quark flavors in high-energy colliders is analyzed. In addition, it is shown how isospin violations in the nucleon help to explain the so-called "NuTeV anomaly".
0911.2812
Jonathan Rosner
Bhubanjyoti Bhattacharya and Jonathan L. Rosner
Charmed meson decays to two pseudoscalars
15 pages, 7 figures, to be submitted to Phys. Rev. D
Phys.Rev.D81:014026,2010
10.1103/PhysRevD.81.014026
EFI 09-32
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A recent update of data on the decays of $D^0$, $D^+$, and $D_s^+$ to pairs of light pseudoscalars calls for a renewed analysis of key decay amplitudes and tests of flavor symmetry. The present data change our previous understanding of relative phases between amplitudes that describe Cabibbo-favored decays of the charmed mesons. The new data also seem to favor a smaller octet-singlet mixing angle for the $\eta$ and $\eta'$ mesons when singly-Cabibbo-suppressed processes are taken into account. We also discuss the effects of the new data on interference between Cabibbo-favored and doubly-Cabibbo-suppressed decays.
[ { "created": "Sat, 14 Nov 2009 22:15:39 GMT", "version": "v1" } ]
2010-04-06
[ [ "Bhattacharya", "Bhubanjyoti", "" ], [ "Rosner", "Jonathan L.", "" ] ]
A recent update of data on the decays of $D^0$, $D^+$, and $D_s^+$ to pairs of light pseudoscalars calls for a renewed analysis of key decay amplitudes and tests of flavor symmetry. The present data change our previous understanding of relative phases between amplitudes that describe Cabibbo-favored decays of the charmed mesons. The new data also seem to favor a smaller octet-singlet mixing angle for the $\eta$ and $\eta'$ mesons when singly-Cabibbo-suppressed processes are taken into account. We also discuss the effects of the new data on interference between Cabibbo-favored and doubly-Cabibbo-suppressed decays.
hep-ph/0407347
Jan Kalinowski
S.Y. Choi, J. Kalinowski, Y. Liao, P.M. Zerwas
H/A Higgs Mixing in CP-Noninvariant Supersymmetric Theories
LaTeX, 1+20 pages, 6 figures
Eur.Phys.J.C40:555-564,2005
10.1140/epjc/s2005-02145-9
DESY 04-055
hep-ph
null
For large masses, the two heavy neutral Higgs bosons are nearly degenerate in many 2--Higgs doublet models, and particularly in supersymmetric models. In such a scenario the mixing between the states can be very large if the theory is CP-noninvariant. We analyze the formalism describing this configuration, and we point to some interesting experimental consequences.
[ { "created": "Thu, 29 Jul 2004 15:49:17 GMT", "version": "v1" } ]
2011-09-13
[ [ "Choi", "S. Y.", "" ], [ "Kalinowski", "J.", "" ], [ "Liao", "Y.", "" ], [ "Zerwas", "P. M.", "" ] ]
For large masses, the two heavy neutral Higgs bosons are nearly degenerate in many 2--Higgs doublet models, and particularly in supersymmetric models. In such a scenario the mixing between the states can be very large if the theory is CP-noninvariant. We analyze the formalism describing this configuration, and we point to some interesting experimental consequences.
0811.1318
Tomohiro Matsuda
Tomohiro Matsuda
Curvatons and inhomogeneous scenarios with deviation from slow-roll
14pages, 1 figure, Latex2e, note added, to appear in JCAP
JCAP 0812:001,2008
10.1088/1475-7516/2008/12/001
null
hep-ph astro-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The spectral index is studied at the point where scalar fields deviate from slow-roll during inflation. Considering the deviation that may cause a significant difference to the time derivative of the Hubble parameter and also to the terms in the evolution equation, we show how the deviation affects the spectral index of the curvature perturbations. Considering conventional inflation, curvatons and other inhomogeneous scenarios as mechanisms for generating the cosmological perturbation, we examine whether the spectral index induced by the deviation from the standard slow-roll can explain the spectral index n-1>0 at k=0.002/Mpc while keeping n-1<0 at a smaller scale.
[ { "created": "Sun, 9 Nov 2008 05:11:45 GMT", "version": "v1" }, { "created": "Sat, 22 Nov 2008 06:24:14 GMT", "version": "v2" } ]
2010-04-21
[ [ "Matsuda", "Tomohiro", "" ] ]
The spectral index is studied at the point where scalar fields deviate from slow-roll during inflation. Considering the deviation that may cause a significant difference to the time derivative of the Hubble parameter and also to the terms in the evolution equation, we show how the deviation affects the spectral index of the curvature perturbations. Considering conventional inflation, curvatons and other inhomogeneous scenarios as mechanisms for generating the cosmological perturbation, we examine whether the spectral index induced by the deviation from the standard slow-roll can explain the spectral index n-1>0 at k=0.002/Mpc while keeping n-1<0 at a smaller scale.
hep-ph/9307338
Lynne Orr
L.H. Orr, Yu.L. Dokshitzer, V.A. Khoze, and W.J. Stirling
Gluon Radiation and Top Width Effects
UCD-93-23. Numbering of references corrected
null
null
null
hep-ph
null
The large width of the top quark influences the way gluons are radiated in top events, giving rise to interesting interference effects in top production and decay. We discuss top width effects in soft guon radiation in $\ee \to \tt$ at high energies and near $\tt$ threshold.
[ { "created": "Mon, 26 Jul 1993 20:09:00 GMT", "version": "v1" }, { "created": "Tue, 27 Jul 1993 22:04:00 GMT", "version": "v2" } ]
2008-02-03
[ [ "Orr", "L. H.", "" ], [ "Dokshitzer", "Yu. L.", "" ], [ "Khoze", "V. A.", "" ], [ "Stirling", "W. J.", "" ] ]
The large width of the top quark influences the way gluons are radiated in top events, giving rise to interesting interference effects in top production and decay. We discuss top width effects in soft guon radiation in $\ee \to \tt$ at high energies and near $\tt$ threshold.
1010.1152
Dr. Rukmani Mohanta
R. Mohanta, A.K. Giri
Fourth generation effect on $\Lambda_b$ decays
19 pages, 7 figures, typos corrected, published version
Phys.Rev.D82:094022,2010
10.1103/PhysRevD.82.094022
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The rare decays of $\Lambda_b$ baryon governed by the quark level transitions $ b \to s$, are investigated in the fourth quark generation model popularly known as SM4. Recently it has been shown that SM4, which is a very simple extension of the standard model, can successfully explain several anomalies observed in the CP violation parameters of $B$ and $B_s$ mesons. We find that in this model due to the additional contributions coming from the heavy $t'$ quark in the loop, the branching ratios and other observables in rare $\Lambda_b$ decays deviate significantly from their SM values. Some of these modes are within the reach of LHCb experiment and search for such channels are strongly argued.
[ { "created": "Wed, 6 Oct 2010 13:53:07 GMT", "version": "v1" }, { "created": "Wed, 20 Oct 2010 16:43:28 GMT", "version": "v2" }, { "created": "Thu, 18 Nov 2010 13:13:27 GMT", "version": "v3" } ]
2015-03-17
[ [ "Mohanta", "R.", "" ], [ "Giri", "A. K.", "" ] ]
The rare decays of $\Lambda_b$ baryon governed by the quark level transitions $ b \to s$, are investigated in the fourth quark generation model popularly known as SM4. Recently it has been shown that SM4, which is a very simple extension of the standard model, can successfully explain several anomalies observed in the CP violation parameters of $B$ and $B_s$ mesons. We find that in this model due to the additional contributions coming from the heavy $t'$ quark in the loop, the branching ratios and other observables in rare $\Lambda_b$ decays deviate significantly from their SM values. Some of these modes are within the reach of LHCb experiment and search for such channels are strongly argued.
1710.08283
Lu Meng
Lu Meng, Hao-Song Li, Zhan-Wei Liu and Shi-Lin Zhu
Magnetic moments of the spin-${3\over 2}$ doubly heavy baryons
10 pages,2 figures. arXiv admin note: text overlap with arXiv:1707.02765. Replace the published version
null
10.1140/epjc/s10052-017-5447-8
null
hep-ph hep-ex hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we investigate the chiral corrections to the magnetic moments of the spin-$3\over 2$ doubly charmed baryons systematically up to next-to-next-to-leading order with the heavy baryon chiral perturbation theory. The numerical results are given up to next-to-leading order: $\mu_{\Xi^{*++}_{cc}}=1.72\mu_{N}$, $\mu_{\Xi^{*+}_{cc}}=-0.09\mu_{N}$, $\mu_{\Omega^{*+}_{cc}}=0.99\mu_{N}$. As a by-product, we have also calculated the magnetic moments of the spin-$3\over 2$ doubly bottom baryons and charmed bottom baryons: $\mu_{\Xi^{*0}_{bb}}=0.63\mu_{N}$, $\mu_{\Xi^{*-}_{bb}}=-0.79\mu_{N}$, $\mu_{\Omega^{*-}_{bb}}=0.12\mu_{N}$, $\mu_{\Xi^{*+}_{bc}}=1.12\mu_{N}$, $\mu_{\Xi^{*0}_{bc}}=-0.40\mu_{N}$, $\mu_{\Omega^{*0}_{bc}}=0.56\mu_{N}$.
[ { "created": "Fri, 20 Oct 2017 03:23:12 GMT", "version": "v1" }, { "created": "Sun, 17 Dec 2017 23:33:03 GMT", "version": "v2" }, { "created": "Thu, 7 Jun 2018 05:51:49 GMT", "version": "v3" } ]
2018-06-08
[ [ "Meng", "Lu", "" ], [ "Li", "Hao-Song", "" ], [ "Liu", "Zhan-Wei", "" ], [ "Zhu", "Shi-Lin", "" ] ]
In this work, we investigate the chiral corrections to the magnetic moments of the spin-$3\over 2$ doubly charmed baryons systematically up to next-to-next-to-leading order with the heavy baryon chiral perturbation theory. The numerical results are given up to next-to-leading order: $\mu_{\Xi^{*++}_{cc}}=1.72\mu_{N}$, $\mu_{\Xi^{*+}_{cc}}=-0.09\mu_{N}$, $\mu_{\Omega^{*+}_{cc}}=0.99\mu_{N}$. As a by-product, we have also calculated the magnetic moments of the spin-$3\over 2$ doubly bottom baryons and charmed bottom baryons: $\mu_{\Xi^{*0}_{bb}}=0.63\mu_{N}$, $\mu_{\Xi^{*-}_{bb}}=-0.79\mu_{N}$, $\mu_{\Omega^{*-}_{bb}}=0.12\mu_{N}$, $\mu_{\Xi^{*+}_{bc}}=1.12\mu_{N}$, $\mu_{\Xi^{*0}_{bc}}=-0.40\mu_{N}$, $\mu_{\Omega^{*0}_{bc}}=0.56\mu_{N}$.
2008.07833
Zhi-Gang Wang
Zhi-Gang Wang
Analysis of the $X_0(2900)$ as the scalar tetraquark state via the QCD sum rules
7 pages, 2 figures
Int. J. Mod. Phys. A35 (2020) 2050187
10.1142/S0217751X20501870
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this article, we study the axialvector-diquark-axialvector-antidiquark ($AA$) type and scalar-diquark-scalar-antidiquark ($SS$) type fully open flavor $cs\bar{u}\bar{d}$ tetraquark states with the spin-parity $J^P={0}^+$ via the QCD sum rules. The predicted masses $M_{AA}=2.91\pm0.12\,\rm{GeV}$ and $M_{SS}=3.05\pm0.10\,\rm{GeV}$ support assigning the $X_0(2900)$ to be the $AA$-type scalar $cs\bar{u}\bar{d}$ tetraquark state.
[ { "created": "Tue, 18 Aug 2020 10:10:03 GMT", "version": "v1" }, { "created": "Tue, 15 Sep 2020 07:42:02 GMT", "version": "v2" }, { "created": "Sun, 11 Oct 2020 02:08:18 GMT", "version": "v3" } ]
2020-10-13
[ [ "Wang", "Zhi-Gang", "" ] ]
In this article, we study the axialvector-diquark-axialvector-antidiquark ($AA$) type and scalar-diquark-scalar-antidiquark ($SS$) type fully open flavor $cs\bar{u}\bar{d}$ tetraquark states with the spin-parity $J^P={0}^+$ via the QCD sum rules. The predicted masses $M_{AA}=2.91\pm0.12\,\rm{GeV}$ and $M_{SS}=3.05\pm0.10\,\rm{GeV}$ support assigning the $X_0(2900)$ to be the $AA$-type scalar $cs\bar{u}\bar{d}$ tetraquark state.
hep-ph/0010114
Dima Kuzmenko
D.S.Kuzmenko, Yu.A.Simonov (ITEP, Moscow)
QCD string in mesons and baryons
LaTeX2e, 13 pages, 20 GIF images, to appear in Yad.Phys
Phys.Atom.Nucl. 64 (2001) 107-119; Yad.Fiz. 64 (2001) 110-122
10.1134/1.1344949
null
hep-ph hep-lat
null
Field distributions generated by static quark-antiquark and QQQ sources are calculated analytically in the framework of Gaussian (bilocal) approximation of Field Correlator Method (FCM). Special attention is paid to the QQQ system and asymmetric configurations are also studied. In both quark-antiquark and QQQ cases the string consists mainly of longitudinal color electric field. Transverse color electric field contribution is shown to be less then 3%. Baryon string has an Y-like shape with a deep well at the string junction position. Field distributions for quark-diquark and for three quarks on one line are considered. The interaction potential for quarks forming an equilateral triangle is calculated. The material of the paper is illustrated by 24 3D colored pictures.
[ { "created": "Wed, 11 Oct 2000 17:34:07 GMT", "version": "v1" } ]
2009-10-31
[ [ "Kuzmenko", "D. S.", "", "ITEP, Moscow" ], [ "Simonov", "Yu. A.", "", "ITEP, Moscow" ] ]
Field distributions generated by static quark-antiquark and QQQ sources are calculated analytically in the framework of Gaussian (bilocal) approximation of Field Correlator Method (FCM). Special attention is paid to the QQQ system and asymmetric configurations are also studied. In both quark-antiquark and QQQ cases the string consists mainly of longitudinal color electric field. Transverse color electric field contribution is shown to be less then 3%. Baryon string has an Y-like shape with a deep well at the string junction position. Field distributions for quark-diquark and for three quarks on one line are considered. The interaction potential for quarks forming an equilateral triangle is calculated. The material of the paper is illustrated by 24 3D colored pictures.
1805.03279
Joel Jones-Perez
M. V. Ascencio-Sosa, A. M. Calatayud-Cadenillas, A. M. Gago, J. Jones-P\'erez
Matter effects in neutrino visible decay at future long-baseline experiments
18 pages; v2: Minor changes, version accepted for publication in EPJC
null
10.1140/epjc/s10052-018-6276-0
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Neutrino visible decay in the presence of matter is re-evaluated. We study these effects in two future long-baseline experiments where matter effects are relevant: DUNE (1300 km) and a hypothetical beam aimed towards ANDES (7650 km). We find that matter effects are negligible for the visible component of neutrino decay at DUNE, being much more relevant at ANDES. We perform a detailed simulation of DUNE, considering $\nu_\mu$ disappearance and $\nu_e$ appearance channels, for both FHC and RHC modes. The sensitivity to the decay constant $\alpha_3$ can be as low as $2\times10^{-6}$ eV$^2$ at 90% C.L., depending on the neutrino masses and type of coupling. We also show the impact of neutrino decay in the determination of $\theta_{23}$ and $\delta_{\rm CP}$, and find that the best-fit value of $\theta_{23}$ can move from a true value at the lower octant towards the higher octant.
[ { "created": "Tue, 8 May 2018 20:50:52 GMT", "version": "v1" }, { "created": "Thu, 27 Sep 2018 13:06:16 GMT", "version": "v2" } ]
2018-11-14
[ [ "Ascencio-Sosa", "M. V.", "" ], [ "Calatayud-Cadenillas", "A. M.", "" ], [ "Gago", "A. M.", "" ], [ "Jones-Pérez", "J.", "" ] ]
Neutrino visible decay in the presence of matter is re-evaluated. We study these effects in two future long-baseline experiments where matter effects are relevant: DUNE (1300 km) and a hypothetical beam aimed towards ANDES (7650 km). We find that matter effects are negligible for the visible component of neutrino decay at DUNE, being much more relevant at ANDES. We perform a detailed simulation of DUNE, considering $\nu_\mu$ disappearance and $\nu_e$ appearance channels, for both FHC and RHC modes. The sensitivity to the decay constant $\alpha_3$ can be as low as $2\times10^{-6}$ eV$^2$ at 90% C.L., depending on the neutrino masses and type of coupling. We also show the impact of neutrino decay in the determination of $\theta_{23}$ and $\delta_{\rm CP}$, and find that the best-fit value of $\theta_{23}$ can move from a true value at the lower octant towards the higher octant.
1208.2554
Johan Bijnens
Mehran Zahiri Abyaneh
The Anatomy of the Pion Loop Hadronic Light by Light Scattering Contribution to the Muon Magnetic Anomaly
47 pages, Master thesis supervisor Johan Bijnens
null
null
LU TP 12-26
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This thesis investigates the Hadronic Light by Light (HLL) scattering contribution to the muon $g-2$, which is one of the most important low energy hadronic effects and consists mainly of the quark loop, the pion pole and the charged pion and kaon loops. In this work the charged pion loop has been investigated more closely. After reviewing the subject a preliminary introduction to Chiral Perturbation Theory (ChPT), Hidden Local Symmetry (HLS) model and the full Vector Meson Dominance (VMD) model is given, and they are used to calculate the pion loop HLL scattering contribution to the muon anomalous magnetic moment. The momentum regions where the contributions of the bare pion loop, the VMD model, and the HLS come from, have been studied, to understand why different models give very different results. The effects of pion polarizability and charge radius on the HLL scattering, which appear at order $p^4$ in ChPT, from $ L_9$ and $ L_{10}$ Lagrangian terms and their momentum regions have been studied.
[ { "created": "Mon, 13 Aug 2012 11:42:47 GMT", "version": "v1" } ]
2012-08-14
[ [ "Abyaneh", "Mehran Zahiri", "" ] ]
This thesis investigates the Hadronic Light by Light (HLL) scattering contribution to the muon $g-2$, which is one of the most important low energy hadronic effects and consists mainly of the quark loop, the pion pole and the charged pion and kaon loops. In this work the charged pion loop has been investigated more closely. After reviewing the subject a preliminary introduction to Chiral Perturbation Theory (ChPT), Hidden Local Symmetry (HLS) model and the full Vector Meson Dominance (VMD) model is given, and they are used to calculate the pion loop HLL scattering contribution to the muon anomalous magnetic moment. The momentum regions where the contributions of the bare pion loop, the VMD model, and the HLS come from, have been studied, to understand why different models give very different results. The effects of pion polarizability and charge radius on the HLL scattering, which appear at order $p^4$ in ChPT, from $ L_9$ and $ L_{10}$ Lagrangian terms and their momentum regions have been studied.
hep-ph/0206262
Masaaki Kuroda
M. Kuroda (Meijigakuin University) and D. Schildknecht (Bielefeld University)
Diffractive production and the total cross section in deep inelastic scattering
19 pages with 4 figures,(eps and ps files), Latex
Phys.Rev. D66 (2002) 094005
10.1103/PhysRevD.66.094005
null
hep-ph
null
We explore the consequences for diffractive production, gamma* p --> X p, in deep inelastic scattering at low values of x\sim Q^2/W^2 <<1 that follow from our recent representation of the total photoabsorption cross section, sigma_{gamma* p}, in the generalized vector dominance/ color dipole picture(GVD/CDP) that is based on the generic structure of the two-gluon-exchange from QCD. Sum rules are derived that relate the transverse and the longitudinal (virtual) photoabsorption cross section to diffractive forward production of q q-bar states that carry photon quantum numbers ("elastic diffraction"). Agreement with experiment in the W^2 and Q^2 dependence is found for M_X^2/Q^2<<1, where M_X is the mass of the produced system X. An additional component ("inelastic diffraction"), not actively contributing to the forward Compton amplitude, is needed for diffractive production at high values of M_X. Our previous theoretical representation of the total photoabsorption cross section sigma_{gamma* p}=sigma_{gamma* p}(eta), in terms of the scaling variable eta=(Q^2+m_0^2)/Lambda^2(W^2) is extended to include the entire kinematic domain, x=<0.1 and all Q^2 with Q^2>=0, where scaling in eta holds experimentally.
[ { "created": "Wed, 26 Jun 2002 05:59:32 GMT", "version": "v1" }, { "created": "Tue, 24 Sep 2002 03:05:14 GMT", "version": "v2" } ]
2009-11-07
[ [ "Kuroda", "M.", "", "Meijigakuin University" ], [ "Schildknecht", "D.", "", "Bielefeld\n University" ] ]
We explore the consequences for diffractive production, gamma* p --> X p, in deep inelastic scattering at low values of x\sim Q^2/W^2 <<1 that follow from our recent representation of the total photoabsorption cross section, sigma_{gamma* p}, in the generalized vector dominance/ color dipole picture(GVD/CDP) that is based on the generic structure of the two-gluon-exchange from QCD. Sum rules are derived that relate the transverse and the longitudinal (virtual) photoabsorption cross section to diffractive forward production of q q-bar states that carry photon quantum numbers ("elastic diffraction"). Agreement with experiment in the W^2 and Q^2 dependence is found for M_X^2/Q^2<<1, where M_X is the mass of the produced system X. An additional component ("inelastic diffraction"), not actively contributing to the forward Compton amplitude, is needed for diffractive production at high values of M_X. Our previous theoretical representation of the total photoabsorption cross section sigma_{gamma* p}=sigma_{gamma* p}(eta), in terms of the scaling variable eta=(Q^2+m_0^2)/Lambda^2(W^2) is extended to include the entire kinematic domain, x=<0.1 and all Q^2 with Q^2>=0, where scaling in eta holds experimentally.
1607.05541
Jeremie Quevillon
John Ellis, J\'er\'emie Quevillon and Ver\'onica Sanz
Doubling Up on Supersymmetry in the Higgs Sector
24 pages, 8 figures
null
10.1007/JHEP10(2016)086
KCL-PH-TH/2016-42, CERN-TH/2016-164
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We explore the possibility that physics at the TeV scale possesses approximate $N = 2$ supersymmetry, which is reduced to the $N=1$ minimal supersymmetric extension of the Standard Model (MSSM) at the electroweak scale. This doubling of supersymmetry modifies the Higgs sector of the theory, with consequences for the masses, mixings and couplings of the MSSM Higgs bosons, whose phenomenological consequences we explore in this paper. The mass of the lightest neutral Higgs boson $h$ is independent of $\tan \beta$ at the tree level, and the decoupling limit is realized whatever the values of the heavy Higgs boson masses. Radiative corrections to the top quark and stop squarks dominate over those due to particles in $N=2$ gauge multiplets. We assume that these radiative corrections fix $m_h \simeq 125$ GeV, whatever the masses of the other neutral Higgs bosons $H, A$, a scenario that we term the $h$2MSSM. Since the $H, A$ bosons decouple from the $W$ and $Z$ bosons in the $h$2MSSM at tree level, only the LHC constraints on $H, A$ and $H^\pm$ couplings to fermions are applicable. These and the indirect constraints from LHC measurements of $h$ couplings are consistent with $m_A \gtrsim 200$ GeV for $\tan \beta \in (2, 8)$ in the $h$2MSSM.
[ { "created": "Tue, 19 Jul 2016 12:21:37 GMT", "version": "v1" } ]
2016-11-23
[ [ "Ellis", "John", "" ], [ "Quevillon", "Jérémie", "" ], [ "Sanz", "Verónica", "" ] ]
We explore the possibility that physics at the TeV scale possesses approximate $N = 2$ supersymmetry, which is reduced to the $N=1$ minimal supersymmetric extension of the Standard Model (MSSM) at the electroweak scale. This doubling of supersymmetry modifies the Higgs sector of the theory, with consequences for the masses, mixings and couplings of the MSSM Higgs bosons, whose phenomenological consequences we explore in this paper. The mass of the lightest neutral Higgs boson $h$ is independent of $\tan \beta$ at the tree level, and the decoupling limit is realized whatever the values of the heavy Higgs boson masses. Radiative corrections to the top quark and stop squarks dominate over those due to particles in $N=2$ gauge multiplets. We assume that these radiative corrections fix $m_h \simeq 125$ GeV, whatever the masses of the other neutral Higgs bosons $H, A$, a scenario that we term the $h$2MSSM. Since the $H, A$ bosons decouple from the $W$ and $Z$ bosons in the $h$2MSSM at tree level, only the LHC constraints on $H, A$ and $H^\pm$ couplings to fermions are applicable. These and the indirect constraints from LHC measurements of $h$ couplings are consistent with $m_A \gtrsim 200$ GeV for $\tan \beta \in (2, 8)$ in the $h$2MSSM.
2306.01305
Kohei Fujikura
Kohei Fujikura, Yuichiro Nakai, Ryosuke Sato, Yaoduo Wang
Cosmological Phase Transitions in Composite Higgs Models
17 pages, 2 figures
null
null
OU-HET-1190, UT-Komaba/23-5
hep-ph astro-ph.CO hep-th
http://creativecommons.org/licenses/by/4.0/
We investigate cosmological phase transitions in various composite Higgs models consisting of four-dimensional asymptotically-free gauge field theories. Each model may lead to a confinement-deconfinement transition and a phase transition associated with the spontaneous breaking of a global symmetry that realizes the Standard Model Higgs field as a pseudo-Nambu-Goldstone boson. Based on the argument of universality, we discuss the order of the phase transition associated with the global symmetry breaking by studying the renormalization group flow of the corresponding linear sigma model at finite temperature, which is calculated by utilizing the $\epsilon$-expansion technique at the one-loop order. Our analysis indicates that some composite Higgs models accommodate phenomenologically interesting first-order phase transitions. We also explore the confinement-deconfinement transition in a UV-completed composite Higgs model based on a $Sp(2N_c)$ gauge theory. It is found that the first-order phase transition is favored when the number of degrees of freedom for the $Sp(2N_c)$ gauge field is much larger than that of matter fields in the fundamental representation of $Sp(2N_c)$. We comment on the gravitational wave signal generated by the confinement-deconfinement transition and its detectability at future observations. Our discussions motivate further studies on phase transitions in composite Higgs models with the use of lattice simulations.
[ { "created": "Fri, 2 Jun 2023 07:05:53 GMT", "version": "v1" } ]
2023-06-05
[ [ "Fujikura", "Kohei", "" ], [ "Nakai", "Yuichiro", "" ], [ "Sato", "Ryosuke", "" ], [ "Wang", "Yaoduo", "" ] ]
We investigate cosmological phase transitions in various composite Higgs models consisting of four-dimensional asymptotically-free gauge field theories. Each model may lead to a confinement-deconfinement transition and a phase transition associated with the spontaneous breaking of a global symmetry that realizes the Standard Model Higgs field as a pseudo-Nambu-Goldstone boson. Based on the argument of universality, we discuss the order of the phase transition associated with the global symmetry breaking by studying the renormalization group flow of the corresponding linear sigma model at finite temperature, which is calculated by utilizing the $\epsilon$-expansion technique at the one-loop order. Our analysis indicates that some composite Higgs models accommodate phenomenologically interesting first-order phase transitions. We also explore the confinement-deconfinement transition in a UV-completed composite Higgs model based on a $Sp(2N_c)$ gauge theory. It is found that the first-order phase transition is favored when the number of degrees of freedom for the $Sp(2N_c)$ gauge field is much larger than that of matter fields in the fundamental representation of $Sp(2N_c)$. We comment on the gravitational wave signal generated by the confinement-deconfinement transition and its detectability at future observations. Our discussions motivate further studies on phase transitions in composite Higgs models with the use of lattice simulations.
hep-ph/0602058
Steen Hannestad
Steen Hannestad
Primordial Neutrinos
50 pages, 3 figures, for Annual Review of Nuclear and Particle Science
Ann.Rev.Nucl.Part.Sci.56:137-161,2006
10.1146/annurev.nucl.56.080805.140548
null
hep-ph
null
The connection between cosmological observations and neutrino physics is discussed in detail. Neutrinos decouple from thermal contact in the early Universe at a temperature of order 1 MeV which coincides with the temperature where light element synthesis occurs. Observation of light element abundances therefore provides important information on such properties as neutrino energy density and chemical potential. Precision observations of the cosmic microwave background and large scale structure of galaxies can be used to probe neutrino masses with greater precision than current laboratory experiments. In this review I discuss current cosmological bounds on neutrino properties, as well as possible bounds from upcoming measurements.
[ { "created": "Tue, 7 Feb 2006 12:11:21 GMT", "version": "v1" } ]
2008-11-26
[ [ "Hannestad", "Steen", "" ] ]
The connection between cosmological observations and neutrino physics is discussed in detail. Neutrinos decouple from thermal contact in the early Universe at a temperature of order 1 MeV which coincides with the temperature where light element synthesis occurs. Observation of light element abundances therefore provides important information on such properties as neutrino energy density and chemical potential. Precision observations of the cosmic microwave background and large scale structure of galaxies can be used to probe neutrino masses with greater precision than current laboratory experiments. In this review I discuss current cosmological bounds on neutrino properties, as well as possible bounds from upcoming measurements.
1703.00831
Istv\'an Kaposv\'ari
A. Jakov\'ac, I. Kaposv\'ari, A. Patk\'os
Pseudo-Goldstone excitations in chiral Yukawa-theories with quadratic explicit symmetry breaking
21 pages, 11 figures
Phys. Rev. D 96, 076018 (2017)
10.1103/PhysRevD.96.076018
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The symmetry breakdown pattern is studied in models containing one fermion flavor multiplet and a multicomponent scalar field, supplemented with a chiral Yukawa-interaction, and in presence of an explicit symmetry breaking source quadratic in the scalar field. In a detailed investigation of the model with $U_L(1) \times U_R(1)$ chiral symmetry it is shown that by diminishing the strength of quadratic explicit symmetry breaking one can still keep stable the mass ratio of the fermionic and the pseudo-Goldstone excitation. At the same time the mass ratio of the two bosonic excitations appears to approach a limiting value depending only on the infrared value of the first ratio, but not on the microscopic (ultraviolet) coupling values. The observations receive a general interpretation by the existence of an ultraviolet fixed point located in the symmetric phase. Understanding the general conditions for its existence allows the construction of a similar theory with $U_L(2) \times U_R(2)$ chiral symmetry. All results of the present investigation were obtained with nonperturbative functional renormalisation group technique making use of the first two approximations to the gradient expansion of the effective action.
[ { "created": "Thu, 2 Mar 2017 15:29:03 GMT", "version": "v1" }, { "created": "Thu, 2 Nov 2017 12:48:57 GMT", "version": "v2" } ]
2017-11-03
[ [ "Jakovác", "A.", "" ], [ "Kaposvári", "I.", "" ], [ "Patkós", "A.", "" ] ]
The symmetry breakdown pattern is studied in models containing one fermion flavor multiplet and a multicomponent scalar field, supplemented with a chiral Yukawa-interaction, and in presence of an explicit symmetry breaking source quadratic in the scalar field. In a detailed investigation of the model with $U_L(1) \times U_R(1)$ chiral symmetry it is shown that by diminishing the strength of quadratic explicit symmetry breaking one can still keep stable the mass ratio of the fermionic and the pseudo-Goldstone excitation. At the same time the mass ratio of the two bosonic excitations appears to approach a limiting value depending only on the infrared value of the first ratio, but not on the microscopic (ultraviolet) coupling values. The observations receive a general interpretation by the existence of an ultraviolet fixed point located in the symmetric phase. Understanding the general conditions for its existence allows the construction of a similar theory with $U_L(2) \times U_R(2)$ chiral symmetry. All results of the present investigation were obtained with nonperturbative functional renormalisation group technique making use of the first two approximations to the gradient expansion of the effective action.
hep-ph/0412038
Javier Ferrandis
Javier Ferrandis and Sandip Pakvasa
QLC relation and neutrino mass hierarchy
7 pages, 0 figures
Phys.Rev.D71:033004,2005
10.1103/PhysRevD.71.033004
UH-511-1063-2004, LBNL-56686
hep-ph
null
Latest measurements have revealed that the deviation from a maximal solar mixing angle is approximately the Cabibbo angle, i.e. QLC relation. We argue that it is not plausible that this deviation from maximality, be it a coincidence or not, comes from the charged lepton mixing. Consequently we have calculated the required corrections to the exactly bimaximal neutrino mass matrix ansatz necessary to account for the solar mass difference and the solar mixing angle. We point out that the relative size of these two corrections depends strongly on the hierarchy case under consideration. We find that the inverted hierarchy case with opposite CP parities, which is known to guarantee the RGE stability of the solar mixing angle, offers the most plausible scenario for a high energy origin of a QLC-corrected bimaximal neutrino mass matrix. This possibility may allow us to explain the QLC relation in connection with the origin of the charged fermion mass matrices.
[ { "created": "Thu, 2 Dec 2004 20:27:25 GMT", "version": "v1" }, { "created": "Thu, 27 Jan 2005 01:38:49 GMT", "version": "v2" } ]
2014-11-18
[ [ "Ferrandis", "Javier", "" ], [ "Pakvasa", "Sandip", "" ] ]
Latest measurements have revealed that the deviation from a maximal solar mixing angle is approximately the Cabibbo angle, i.e. QLC relation. We argue that it is not plausible that this deviation from maximality, be it a coincidence or not, comes from the charged lepton mixing. Consequently we have calculated the required corrections to the exactly bimaximal neutrino mass matrix ansatz necessary to account for the solar mass difference and the solar mixing angle. We point out that the relative size of these two corrections depends strongly on the hierarchy case under consideration. We find that the inverted hierarchy case with opposite CP parities, which is known to guarantee the RGE stability of the solar mixing angle, offers the most plausible scenario for a high energy origin of a QLC-corrected bimaximal neutrino mass matrix. This possibility may allow us to explain the QLC relation in connection with the origin of the charged fermion mass matrices.
1601.05114
Henrique Boschi-Filho
Eduardo Folco Capossoli, Danning Li, and Henrique Boschi-Filho
Pomeron and Odderon Regge Trajectories from a Dynamical Holographic Model
V3: 12 pages, 8 figures, 2 tables. Results slightly modified due to the redefinition of the relation between the five dimensional mass, conformal dimension and spin. Text improved. We also comment now that the twist two operator does not work in this model. References added. This version matches the published one in PLB
Phys. Lett. B 760 (2016) 101
10.1016/j.physletb.2016.06.049
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we use gauge/string dualities and a dynamical model that takes into account dynamical corrections to the metric of the anti de Sitter space due to a quadratic dilaton field and calculate the masses of even and odd spin glueball states with $P=C=+1$, and $P=C=-1$, respectively. Then we construct the corresponding Regge trajectories which are associated with the pomeron for even states with $P=C=+1$, and with the odderon for odd states with $P=C=-1$. We compare our results with those coming from experimental data as well as other models.
[ { "created": "Tue, 19 Jan 2016 22:05:03 GMT", "version": "v1" }, { "created": "Sat, 23 Jan 2016 23:07:22 GMT", "version": "v2" }, { "created": "Thu, 7 Jul 2016 22:15:21 GMT", "version": "v3" } ]
2016-07-11
[ [ "Capossoli", "Eduardo Folco", "" ], [ "Li", "Danning", "" ], [ "Boschi-Filho", "Henrique", "" ] ]
In this work we use gauge/string dualities and a dynamical model that takes into account dynamical corrections to the metric of the anti de Sitter space due to a quadratic dilaton field and calculate the masses of even and odd spin glueball states with $P=C=+1$, and $P=C=-1$, respectively. Then we construct the corresponding Regge trajectories which are associated with the pomeron for even states with $P=C=+1$, and with the odderon for odd states with $P=C=-1$. We compare our results with those coming from experimental data as well as other models.
2310.02311
Alexander Penin A.
Alexander A. Penin and Aneca Su
Oscillating Fields, Emergent Gravity and Particle Traps
5 pages, 2 figures, a few typos corrected
null
10.1103/PhysRevLett.132.051601
ALBERTA-THY-8-23
hep-ph cond-mat.mes-hall hep-th quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the large-scale dynamics of charged particles in a rapidly oscillating field and formulate its classical and quantum effective theory description. The high-order perturbative results for the effective action are presented. Remarkably, the action models the effects of general relativity on the motion of nonrelativistic particles, with the values of the emergent curvature and speed of light determined by the field spatial distribution and frequency. Our results can be applied to a wide range of physical problems including the high-precision analysis and design of the charged particle traps and Floquet quantum materials.
[ { "created": "Tue, 3 Oct 2023 18:00:02 GMT", "version": "v1" }, { "created": "Wed, 18 Oct 2023 17:50:05 GMT", "version": "v2" } ]
2024-01-31
[ [ "Penin", "Alexander A.", "" ], [ "Su", "Aneca", "" ] ]
We study the large-scale dynamics of charged particles in a rapidly oscillating field and formulate its classical and quantum effective theory description. The high-order perturbative results for the effective action are presented. Remarkably, the action models the effects of general relativity on the motion of nonrelativistic particles, with the values of the emergent curvature and speed of light determined by the field spatial distribution and frequency. Our results can be applied to a wide range of physical problems including the high-precision analysis and design of the charged particle traps and Floquet quantum materials.
2002.08979
Robert Shrock
Thomas A. Ryttov and Robert Shrock
Scheme-Independent Series for Anomalous Dimensions of Higher-Spin Operators at an Infrared Fixed Point in a Gauge Theory
22 pages, latex, 7 figures
Phys. Rev. D 101, 076018 (2020)
10.1103/PhysRevD.101.076018
CP3-Origins-2020-n, YITP-SB-2020-2
hep-ph hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider an asymptotically free vectorial gauge theory, with gauge group $G$ and $N_f$ fermions in a representation $R$ of $G$, having an infrared fixed point of the renormalization group. We calculate scheme-independent series expansions for the anomalous dimensions of higher-spin bilinear fermion operators at this infrared fixed point up to $O(\Delta_f^3)$, where $\Delta_f$ is an $N_f$-dependent expansion variable. Our general results are evaluated for several special cases, including the case $G={\rm SU}(N_c)$ with $R$ equal to the fundamental and adjoint representations.
[ { "created": "Thu, 20 Feb 2020 19:08:57 GMT", "version": "v1" } ]
2020-04-27
[ [ "Ryttov", "Thomas A.", "" ], [ "Shrock", "Robert", "" ] ]
We consider an asymptotically free vectorial gauge theory, with gauge group $G$ and $N_f$ fermions in a representation $R$ of $G$, having an infrared fixed point of the renormalization group. We calculate scheme-independent series expansions for the anomalous dimensions of higher-spin bilinear fermion operators at this infrared fixed point up to $O(\Delta_f^3)$, where $\Delta_f$ is an $N_f$-dependent expansion variable. Our general results are evaluated for several special cases, including the case $G={\rm SU}(N_c)$ with $R$ equal to the fundamental and adjoint representations.
1612.09294
Anthony Hartin
A. Hartin
Resonant transitions induced in particle processes by the non-perturbative treatment of strong laser fields
17 pages, 11 figures
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Intense field quantum field theory (IFQFT) is used to determine new phenomenological predictions arising from Compton scattering and pair production in a strong laser field. This theory utilizes exact solutions of fermions embedded in external plane waves which carry over to a strong field fermion propagator. When these strong field fermions also interact with probe photons, the transition probability is enhanced in a series of resonances when the kinematics allow the virtual fermion to go on-shell. An analysis of parameters shows that contemporary experiments could already produce these predicted resonances. With appropriate tuning, resonances can be made arbitrarily sharp, leading to precision calculations of resonance locations and widths, and the runing of coupling constants in strong background fields. New tests of QED could be performed leading to ramifications for our understanding of the quantum vacuum. Such tests extend to QFT in background potentials in general, which may throw light on BSM theories such as QFT in curved space-times.
[ { "created": "Mon, 5 Dec 2016 17:07:51 GMT", "version": "v1" } ]
2016-12-30
[ [ "Hartin", "A.", "" ] ]
Intense field quantum field theory (IFQFT) is used to determine new phenomenological predictions arising from Compton scattering and pair production in a strong laser field. This theory utilizes exact solutions of fermions embedded in external plane waves which carry over to a strong field fermion propagator. When these strong field fermions also interact with probe photons, the transition probability is enhanced in a series of resonances when the kinematics allow the virtual fermion to go on-shell. An analysis of parameters shows that contemporary experiments could already produce these predicted resonances. With appropriate tuning, resonances can be made arbitrarily sharp, leading to precision calculations of resonance locations and widths, and the runing of coupling constants in strong background fields. New tests of QED could be performed leading to ramifications for our understanding of the quantum vacuum. Such tests extend to QFT in background potentials in general, which may throw light on BSM theories such as QFT in curved space-times.
1704.07756
Frans Klinkhamer
F.R. Klinkhamer, P. Nagel
SU(3) sphaleron: Numerical solution
36 pages, 6 figures, v5: published version
Phys. Rev. D 96, 016006 (2017)
10.1103/PhysRevD.96.016006
KA-TP-18-2017
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We complete the construction of the sphaleron $\widehat{S}$ in $SU(3)$ Yang-Mills-Higgs theory with a single Higgs triplet by solving the reduced field equations numerically. The energy of the $SU(3)$ sphaleron $\widehat{S}$ is found to be of the same order as the energy of a previously known solution, the embedded $SU(2)\times U(1)$ sphaleron $S$. In addition, we discuss $\widehat{S}$ in an extended $SU(3)$ Yang-Mills-Higgs theory with three Higgs triplets, where all eight gauge bosons get an equal mass in the vacuum. This extended $SU(3)$ Yang-Mills-Higgs theory may be considered as a toy model of quantum chromodynamics without quark fields and we conjecture that the $\widehat{S}$ gauge fields play a significant role in the nonperturbative dynamics of quantum chromodynamics (which does not have fundamental scalar fields but gets a mass scale from quantum effects).
[ { "created": "Tue, 25 Apr 2017 15:58:52 GMT", "version": "v1" }, { "created": "Tue, 2 May 2017 17:23:41 GMT", "version": "v2" }, { "created": "Mon, 8 May 2017 17:46:56 GMT", "version": "v3" }, { "created": "Tue, 6 Jun 2017 13:13:33 GMT", "version": "v4" }, { "created": "Wed, 12 Jul 2017 16:52:06 GMT", "version": "v5" } ]
2017-07-19
[ [ "Klinkhamer", "F. R.", "" ], [ "Nagel", "P.", "" ] ]
We complete the construction of the sphaleron $\widehat{S}$ in $SU(3)$ Yang-Mills-Higgs theory with a single Higgs triplet by solving the reduced field equations numerically. The energy of the $SU(3)$ sphaleron $\widehat{S}$ is found to be of the same order as the energy of a previously known solution, the embedded $SU(2)\times U(1)$ sphaleron $S$. In addition, we discuss $\widehat{S}$ in an extended $SU(3)$ Yang-Mills-Higgs theory with three Higgs triplets, where all eight gauge bosons get an equal mass in the vacuum. This extended $SU(3)$ Yang-Mills-Higgs theory may be considered as a toy model of quantum chromodynamics without quark fields and we conjecture that the $\widehat{S}$ gauge fields play a significant role in the nonperturbative dynamics of quantum chromodynamics (which does not have fundamental scalar fields but gets a mass scale from quantum effects).
1710.06928
Kazuhiro Watanabe
Jian-Wei Qiu, Kazuhiro Watanabe
Heavy quarkonium production in hadronic collisions in TMD framework
6 pages, 2 figures, proceedings of QCD Evolution 2017, 22-26 May 2017, Newport News, VA-USA
null
null
JLAB-THY-17-2575
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Heavy quarkonium ($\Upsilon$) production at low transverse momentum ($P_\perp$) in high-energy hadronic collisions is revisited from the point of view of transverse momentum dependent (TMD) framework. We perform resummation of double logarithmic correction associated with initial-state soft gluon shower for $b\bar b$ production by employing Collins-Soper-Sterman (CSS) formalism. We show that the CSS formalism provides a nice description of $\Upsilon$ production data in p+$\rm\bar{p}$ collisions at Tevatron and p+p collisions at the LHC.
[ { "created": "Wed, 18 Oct 2017 20:29:45 GMT", "version": "v1" } ]
2018-08-01
[ [ "Qiu", "Jian-Wei", "" ], [ "Watanabe", "Kazuhiro", "" ] ]
Heavy quarkonium ($\Upsilon$) production at low transverse momentum ($P_\perp$) in high-energy hadronic collisions is revisited from the point of view of transverse momentum dependent (TMD) framework. We perform resummation of double logarithmic correction associated with initial-state soft gluon shower for $b\bar b$ production by employing Collins-Soper-Sterman (CSS) formalism. We show that the CSS formalism provides a nice description of $\Upsilon$ production data in p+$\rm\bar{p}$ collisions at Tevatron and p+p collisions at the LHC.
2209.04313
Olga Bessidskaia Bylund
Olga Bessidskaia Bylund (1), Maxime Defurne (1) and Pierre A. M. Guichon (1) ((1) Irfu, CEA, Universit\'e Paris-Saclay, 91191, Gif-sur-Yvette, France)
The Recoil Proton Polarization: a new discriminative DVCS observable
null
null
10.1103/PhysRevD.107.014020
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Generalized parton distributions describe the correlations between the longitudinal momentum and the transverse position of quarks and gluons in a nucleon. They can be constrained by measuring photon leptoproduction observables, arising from the interference between Bethe-Heitler and Deeply virtual Compton scattering processes. At leading-twist/leading-order, the amplitude of the latter is parameterized by complex integrals of the GPDs {H, E, \~H, \~E} . As data collected on an unpolarized or longitudinally polarized target constrains H and \~H, E is poorly known as it requires data collected with a transversely polarized target, which is very challenging to implement in fixed target experiments. The only alternative considered so far has been DVCS on a neutron with a deuterium target, while assuming isospin symmetry and absence of final-state interactions. Today, we introduce the polarization of the recoil proton as a new DVCS observable, highly sensitive to E, which appears feasible for an experimental study at a high-luminosity facility such as Jefferson Lab.
[ { "created": "Fri, 9 Sep 2022 14:13:27 GMT", "version": "v1" }, { "created": "Thu, 19 Jan 2023 19:07:46 GMT", "version": "v2" } ]
2023-01-23
[ [ "Bylund", "Olga Bessidskaia", "" ], [ "Defurne", "Maxime", "" ], [ "Guichon", "Pierre A. M.", "" ] ]
Generalized parton distributions describe the correlations between the longitudinal momentum and the transverse position of quarks and gluons in a nucleon. They can be constrained by measuring photon leptoproduction observables, arising from the interference between Bethe-Heitler and Deeply virtual Compton scattering processes. At leading-twist/leading-order, the amplitude of the latter is parameterized by complex integrals of the GPDs {H, E, \~H, \~E} . As data collected on an unpolarized or longitudinally polarized target constrains H and \~H, E is poorly known as it requires data collected with a transversely polarized target, which is very challenging to implement in fixed target experiments. The only alternative considered so far has been DVCS on a neutron with a deuterium target, while assuming isospin symmetry and absence of final-state interactions. Today, we introduce the polarization of the recoil proton as a new DVCS observable, highly sensitive to E, which appears feasible for an experimental study at a high-luminosity facility such as Jefferson Lab.
2107.02106
Nikolaos Syrrakos
Nikolaos Syrrakos
One-loop Feynman integrals for $2\to3$ scattering involving many scales including internal masses
22 pages, results in ancillary files; v2: fixed a typo in eq. (2.3), includes a new subsection (3.4) on the choice of integral families, version accepted for publication in JHEP
null
null
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
We study several multiscale one-loop five-point families of Feynman integrals. More specifically, we employ the Simplified Differential Equations approach to obtain results in terms of Goncharov polylogarithms of up to transcendental weight four for families with two and three massive external legs and massless propagators, as well as with one massive internal line and up to two massive external legs. This is the first time this computational approach is applied to cases involving internal masses.
[ { "created": "Mon, 5 Jul 2021 16:00:10 GMT", "version": "v1" }, { "created": "Fri, 10 Sep 2021 20:53:19 GMT", "version": "v2" } ]
2021-09-14
[ [ "Syrrakos", "Nikolaos", "" ] ]
We study several multiscale one-loop five-point families of Feynman integrals. More specifically, we employ the Simplified Differential Equations approach to obtain results in terms of Goncharov polylogarithms of up to transcendental weight four for families with two and three massive external legs and massless propagators, as well as with one massive internal line and up to two massive external legs. This is the first time this computational approach is applied to cases involving internal masses.
0807.0509
G\'abor Somogyi
G\'abor Somogyi, Zolt\'an Tr\'ocs\'anyi
A subtraction scheme for computing QCD jet cross sections at NNLO: integrating the subtraction terms I
null
JHEP 0808:042,2008
10.1088/1126-6708/2008/08/042
ZU-TH 12/08
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In previous articles we outlined a subtraction scheme for regularizing doubly-real emission and real-virtual emission in next-to-next-to-leading order (NNLO) calculations of jet cross sections in electron-positron annihilation. In order to find the NNLO correction these subtraction terms have to be integrated over the factorized unresolved phase space and combined with the two-loop corrections. In this paper we perform the integration of all one-parton unresolved subtraction terms.
[ { "created": "Thu, 3 Jul 2008 09:36:30 GMT", "version": "v1" } ]
2008-12-30
[ [ "Somogyi", "Gábor", "" ], [ "Trócsányi", "Zoltán", "" ] ]
In previous articles we outlined a subtraction scheme for regularizing doubly-real emission and real-virtual emission in next-to-next-to-leading order (NNLO) calculations of jet cross sections in electron-positron annihilation. In order to find the NNLO correction these subtraction terms have to be integrated over the factorized unresolved phase space and combined with the two-loop corrections. In this paper we perform the integration of all one-parton unresolved subtraction terms.
hep-ph/9906373
Bronislav Zakharov
Bronislav Zakharov
Transverse spectra of induced radiation
Talk given at 34th Rencontres de Moriond "QCD and High Energy Hadronic Interactions", Les Arcs, France, March 20-27, 1999
null
null
null
hep-ph
null
Transverse spectra of induced radiation are discussed within the light-cone path integral approach to the LPM effect. The results are applicable in both QED and QCD.
[ { "created": "Tue, 15 Jun 1999 16:54:52 GMT", "version": "v1" }, { "created": "Thu, 17 Jun 1999 12:27:19 GMT", "version": "v2" } ]
2007-05-23
[ [ "Zakharov", "Bronislav", "" ] ]
Transverse spectra of induced radiation are discussed within the light-cone path integral approach to the LPM effect. The results are applicable in both QED and QCD.
hep-ph/9705270
John Kenneth Elwood
John K. Elwood, Nikolaos Irges, and Pierre Ramond
A Model of Yukawa Hierarchies
15 pages, no figures, LaTex. Revised version, containing minor typographical corrections, as well as a substantial revision of the final three paragraphs of the text. Submitted to Physics Letters B
Phys.Lett. B413 (1997) 322-330
10.1016/S0370-2693(97)01103-9
UFIFT-HEP-97-17
hep-ph hep-th
null
We present a model for the observed hierarchies among the Yukawa couplings of the standard model in the context of an effective low energy theory with an anomalous U(1) symmetry. This symmetry, a generic feature of superstring compactification, is a remnant of the Green-Schwarz anomaly cancellation mechanism. The gauge group is that of the standard model, augmented by X, the anomalous U(1), and two family-dependent phase symmetries $Y^{(1)}$ and $Y^{(2)}$. The correct hierarchies are reproduced only when $sin^2\theta_w=3/8$ at the cut-off. To cancel anomalies, right-handed neutrinos and other standard model singlets must be introduced. Independently of the charges of the right-handed neutrinos, this model produces the same neutrino mixing matrix and an inverted hierarchy of neutrino masses. The heaviest is the electron neutrino with a mass $\sim 1$ meV, and mixing of the order of $\lambda_c^3$ with each of the other two neutrinos.
[ { "created": "Thu, 8 May 1997 21:58:08 GMT", "version": "v1" }, { "created": "Wed, 21 May 1997 02:50:05 GMT", "version": "v2" } ]
2009-10-30
[ [ "Elwood", "John K.", "" ], [ "Irges", "Nikolaos", "" ], [ "Ramond", "Pierre", "" ] ]
We present a model for the observed hierarchies among the Yukawa couplings of the standard model in the context of an effective low energy theory with an anomalous U(1) symmetry. This symmetry, a generic feature of superstring compactification, is a remnant of the Green-Schwarz anomaly cancellation mechanism. The gauge group is that of the standard model, augmented by X, the anomalous U(1), and two family-dependent phase symmetries $Y^{(1)}$ and $Y^{(2)}$. The correct hierarchies are reproduced only when $sin^2\theta_w=3/8$ at the cut-off. To cancel anomalies, right-handed neutrinos and other standard model singlets must be introduced. Independently of the charges of the right-handed neutrinos, this model produces the same neutrino mixing matrix and an inverted hierarchy of neutrino masses. The heaviest is the electron neutrino with a mass $\sim 1$ meV, and mixing of the order of $\lambda_c^3$ with each of the other two neutrinos.
1108.4656
Igor Shovkovy
Igor A. Shovkovy
Axial Anomaly and Chiral Asymmetry in Magnetized Relativistic Matter
3 pages; contribution to the proceedings of the 19th Particles and Nuclei International Conference (PANIC11), Cambridge, Massachusetts, July 24th-29th, 2011
null
10.1063/1.3700561
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The generation of a chiral shift parameter in the normal ground state of magnetized relativistic matter is discussed. The chiral shift contributes to the axial current density, but does not modify the conventional axial anomaly relation. The analysis based on gauge invariant regularization schemes suggests that this finding is also valid in gauge theories. We argue that the chiral shift parameter can affect observable properties of compact stars. In the regime of heavy ion collisions, the chiral shift parameter can modify the key features of the chiral magnetic effect.
[ { "created": "Tue, 23 Aug 2011 17:04:43 GMT", "version": "v1" } ]
2015-05-30
[ [ "Shovkovy", "Igor A.", "" ] ]
The generation of a chiral shift parameter in the normal ground state of magnetized relativistic matter is discussed. The chiral shift contributes to the axial current density, but does not modify the conventional axial anomaly relation. The analysis based on gauge invariant regularization schemes suggests that this finding is also valid in gauge theories. We argue that the chiral shift parameter can affect observable properties of compact stars. In the regime of heavy ion collisions, the chiral shift parameter can modify the key features of the chiral magnetic effect.
1504.04128
Zhaofeng Kang
Zhaofeng Kang, P. Ko and Jinmian Li
New Physics Opportunities in the Boosted Di-Higgs plus \ET Signature
Version to appear in PRL; major revision according to the referees' suggestion. The supplement file will be available from the e-journal
Phys. Rev. Lett. 116, 131801 (2016)
10.1103/PhysRevLett.116.131801
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Higgs field in the standard model (SM) may couple to new physics sectors related with dark matter and/or massive neutrinos. In this paper we propose a novel signature, the boosted di-Higgs boson plus \ET (which is either a dark matter or neutrino), to probe those new physics sectors. In a large class of models, in particular the supersymmetric SMs and low scale seesaw mechanisms, this signature can play a key role. The signature has clear background, and at the $\sqrt s=$14 TeV high luminosity (HL-)LHC, we can probe it with production rate as low as $\sim$ 0.1 fb. We apply it to benchmark models, supersymmetry in the bino-Higgsino limit, the canonical seesaw model and little Higgs model, finding that masses of Higgsino, right-handed neutrino and heavy vector boson can be probed up to $\sim$ 500 GeV, 650 GeV and 900 GeV, respectively.
[ { "created": "Thu, 16 Apr 2015 08:12:02 GMT", "version": "v1" }, { "created": "Wed, 3 Jun 2015 10:25:30 GMT", "version": "v2" }, { "created": "Tue, 29 Mar 2016 16:21:52 GMT", "version": "v3" } ]
2016-04-06
[ [ "Kang", "Zhaofeng", "" ], [ "Ko", "P.", "" ], [ "Li", "Jinmian", "" ] ]
The Higgs field in the standard model (SM) may couple to new physics sectors related with dark matter and/or massive neutrinos. In this paper we propose a novel signature, the boosted di-Higgs boson plus \ET (which is either a dark matter or neutrino), to probe those new physics sectors. In a large class of models, in particular the supersymmetric SMs and low scale seesaw mechanisms, this signature can play a key role. The signature has clear background, and at the $\sqrt s=$14 TeV high luminosity (HL-)LHC, we can probe it with production rate as low as $\sim$ 0.1 fb. We apply it to benchmark models, supersymmetry in the bino-Higgsino limit, the canonical seesaw model and little Higgs model, finding that masses of Higgsino, right-handed neutrino and heavy vector boson can be probed up to $\sim$ 500 GeV, 650 GeV and 900 GeV, respectively.
2004.03800
Antonio Ortiz
Antonio Ortiz, Antonio Paz, Jose D. Romo, Sushanta Tripathy, Erik A. Zepeda and Irais Bautista
Multi-Parton Interactions in pp collisions from Machine Learning-based regression
7 pages, 4 figures. The original manuscript was slightly extended, a new figure was added
Phys. Rev. D 102, 076014 (2020)
10.1103/PhysRevD.102.076014
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Multi-Parton Interactions (MPI) in pp collisions have attracted the attention of the heavy-ion community since they can help to elucidate the origin of collective-like effects discovered in small collision systems at the LHC. In this work, we report that in PYTHIA 8.244, the charged-particle production in events with a large number of MPI (${\rm N}_{\rm mpi}$) normalized to that obtained in minimum-bias pp collisions shows interesting features. After the normalization to the corresponding $\langle {\rm N}_{\rm mpi} \rangle$, the ratios as a function of $p_{\rm T}$ exhibit a bump at $p_{\rm T}\approx3$ GeV/$c$; and for higher $p_{\rm T}$ ($>8$ GeV/$c$), the ratios are independent of ${\rm N}_{\rm mpi}$. While the size of the bump increases with increasing ${\rm N}_{\rm mpi}$, the behavior at high $p_{\rm T}$ is expected from the "binary scaling" (parton-parton interactions), which holds given the absence of any parton-energy loss mechanism in PYTHIA. The bump at intermediate $p_{\rm T}$ is reminiscent of the Cronin effect observed for the nuclear modification factor in p--Pb collisions. In order to unveil these effects in data, we propose a strategy to construct an event classifier sensitive to MPI using Machine Learning-based regression. The study is conducted using TMVA, and the regression is performed with Boosted Decision Trees (BDT). Event properties like forward charged-particle multiplicity, transverse spherocity and the average transverse momentum ($\langle p_{\rm T} \rangle$) are used for training. The kinematic cuts are defined in accordance with the ALICE detector capabilities. In addition, we also report that if we apply the trained BDT on existing (${\rm INEL}>0$) pp data, i.e. events with at least one primary charged-particle within $|\eta|<1$, the average number of MPI in pp collisions at $\sqrt{s}=5.02$ and 13 TeV are 3.76$\pm1.01$ and 4.65$\pm1.01$, respectively.
[ { "created": "Wed, 8 Apr 2020 04:11:13 GMT", "version": "v1" }, { "created": "Sun, 11 Oct 2020 18:51:03 GMT", "version": "v2" } ]
2020-10-28
[ [ "Ortiz", "Antonio", "" ], [ "Paz", "Antonio", "" ], [ "Romo", "Jose D.", "" ], [ "Tripathy", "Sushanta", "" ], [ "Zepeda", "Erik A.", "" ], [ "Bautista", "Irais", "" ] ]
Multi-Parton Interactions (MPI) in pp collisions have attracted the attention of the heavy-ion community since they can help to elucidate the origin of collective-like effects discovered in small collision systems at the LHC. In this work, we report that in PYTHIA 8.244, the charged-particle production in events with a large number of MPI (${\rm N}_{\rm mpi}$) normalized to that obtained in minimum-bias pp collisions shows interesting features. After the normalization to the corresponding $\langle {\rm N}_{\rm mpi} \rangle$, the ratios as a function of $p_{\rm T}$ exhibit a bump at $p_{\rm T}\approx3$ GeV/$c$; and for higher $p_{\rm T}$ ($>8$ GeV/$c$), the ratios are independent of ${\rm N}_{\rm mpi}$. While the size of the bump increases with increasing ${\rm N}_{\rm mpi}$, the behavior at high $p_{\rm T}$ is expected from the "binary scaling" (parton-parton interactions), which holds given the absence of any parton-energy loss mechanism in PYTHIA. The bump at intermediate $p_{\rm T}$ is reminiscent of the Cronin effect observed for the nuclear modification factor in p--Pb collisions. In order to unveil these effects in data, we propose a strategy to construct an event classifier sensitive to MPI using Machine Learning-based regression. The study is conducted using TMVA, and the regression is performed with Boosted Decision Trees (BDT). Event properties like forward charged-particle multiplicity, transverse spherocity and the average transverse momentum ($\langle p_{\rm T} \rangle$) are used for training. The kinematic cuts are defined in accordance with the ALICE detector capabilities. In addition, we also report that if we apply the trained BDT on existing (${\rm INEL}>0$) pp data, i.e. events with at least one primary charged-particle within $|\eta|<1$, the average number of MPI in pp collisions at $\sqrt{s}=5.02$ and 13 TeV are 3.76$\pm1.01$ and 4.65$\pm1.01$, respectively.
1302.3991
Ivo de Medeiros Varzielas
Ivo de Medeiros Varzielas
Fermion mixing with geometrical CP violation and its tests at the LHC
8 pages, 4 figures. Submitted to the proceedings of Discrete 2012
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We review and clarify some cases of geometrical CP violation, the framework of spontaneous CP violation through complex phases with values that are independent of parameters of the potential. We present a flavour model based on Delta(27) featuring spontaneous CP violation, that can reproduce all quark masses and mixing data. The scalar sector of the model has exotic properties that can be tested at the LHC.
[ { "created": "Sat, 16 Feb 2013 19:20:00 GMT", "version": "v1" } ]
2013-02-19
[ [ "Varzielas", "Ivo de Medeiros", "" ] ]
We review and clarify some cases of geometrical CP violation, the framework of spontaneous CP violation through complex phases with values that are independent of parameters of the potential. We present a flavour model based on Delta(27) featuring spontaneous CP violation, that can reproduce all quark masses and mixing data. The scalar sector of the model has exotic properties that can be tested at the LHC.
0911.1856
Xianhui Zhong
Xian-Hui Zhong and Qiang Zhao
Strong decays of newly observed $D_{sJ}$ states in a constituent quark model with effective Lagrangians
13 pages, 10 figures, to appear in PRD
Phys.Rev.D81:014031,2010
10.1103/PhysRevD.81.014031
null
hep-ph
http://creativecommons.org/licenses/by/3.0/
The strong decay properties of the newly observed states $D_{sJ}(3040)$, $D_{sJ}(2860)$ and $D_{sJ}(2710)$ are studied in a constituent quark model with quark-meson effective Lagrangians. We find that the $D_{sJ}(3040)$ could be identified as the low mass physical state $|2{P_1}>_L$ ($J^P=1^+$) from the $D_{s}(2^1P_1)$-$D_{s}(2^3P_1)$ mixing. The $D_{sJ}(2710)$ is likely to be the low-mass mixed state $|(SD)>_L$ via the $1^3D_1$-$2^3S_1$ mixing. In our model, the $D_{sJ}(2860)$ cannot be assigned to any single state with a narrow width and compatible partial widths to $DK$ and $D^*K$. Thus, we investigate a two-state scenario as proposed in the literature. In our model, one resonance is likely to be the $1^3D_3$ ($J^P=3^-$), which mainly decays into $DK$. The other resonance seems to be the $|1{D_2}'>_H$, i.e. the high-mass state in the $1^1D_2$-$1^3D_2$ mixing with $J^P=2^-$, of which the $D^*K$ channel is its key decay mode. We also discuss implications arising from these assignments and give predictions for their partner states such as $|(SD)'>_H$, $|2{P'_1}>_H$, $2^3P_0$ and $2^3P_2$, which could be helpful for the search for these new states in future experiment.
[ { "created": "Tue, 10 Nov 2009 08:45:40 GMT", "version": "v1" }, { "created": "Fri, 15 Jan 2010 08:56:12 GMT", "version": "v2" } ]
2010-04-06
[ [ "Zhong", "Xian-Hui", "" ], [ "Zhao", "Qiang", "" ] ]
The strong decay properties of the newly observed states $D_{sJ}(3040)$, $D_{sJ}(2860)$ and $D_{sJ}(2710)$ are studied in a constituent quark model with quark-meson effective Lagrangians. We find that the $D_{sJ}(3040)$ could be identified as the low mass physical state $|2{P_1}>_L$ ($J^P=1^+$) from the $D_{s}(2^1P_1)$-$D_{s}(2^3P_1)$ mixing. The $D_{sJ}(2710)$ is likely to be the low-mass mixed state $|(SD)>_L$ via the $1^3D_1$-$2^3S_1$ mixing. In our model, the $D_{sJ}(2860)$ cannot be assigned to any single state with a narrow width and compatible partial widths to $DK$ and $D^*K$. Thus, we investigate a two-state scenario as proposed in the literature. In our model, one resonance is likely to be the $1^3D_3$ ($J^P=3^-$), which mainly decays into $DK$. The other resonance seems to be the $|1{D_2}'>_H$, i.e. the high-mass state in the $1^1D_2$-$1^3D_2$ mixing with $J^P=2^-$, of which the $D^*K$ channel is its key decay mode. We also discuss implications arising from these assignments and give predictions for their partner states such as $|(SD)'>_H$, $|2{P'_1}>_H$, $2^3P_0$ and $2^3P_2$, which could be helpful for the search for these new states in future experiment.
hep-ph/0701129
Walter Goldberger
Walter D. Goldberger
Les Houches Lectures on Effective Field Theories and Gravitational Radiation
Proceedings of Les Houches 2006. LaTeX, 44 pages, 10 figures
null
null
null
hep-ph astro-ph gr-qc hep-th
null
These lectures give an overview of the uses of effective field theories in describing gravitational radiation sources for LIGO or LISA. The first lecture reviews some of the standard ideas of effective field theory (decoupling, matching, power counting) mostly in the context of a simple toy model. The second lecture sets up the problem of calculating gravitational wave emission from non-relativistic binary stars by constructing a tower of effective theories that separately describe each scale in the problem: the internal size of each binary constituent, the orbital separation, and the wavelength of radiated gravitons.
[ { "created": "Tue, 16 Jan 2007 21:15:25 GMT", "version": "v1" } ]
2007-05-23
[ [ "Goldberger", "Walter D.", "" ] ]
These lectures give an overview of the uses of effective field theories in describing gravitational radiation sources for LIGO or LISA. The first lecture reviews some of the standard ideas of effective field theory (decoupling, matching, power counting) mostly in the context of a simple toy model. The second lecture sets up the problem of calculating gravitational wave emission from non-relativistic binary stars by constructing a tower of effective theories that separately describe each scale in the problem: the internal size of each binary constituent, the orbital separation, and the wavelength of radiated gravitons.
hep-ph/0311077
Roland Kirschner
A. Ivanov and R. Kirschner
Diffractive large transferred momentum photoproduction of vector mesons
13 pages LaTex, 3 figures, to appear in EPJC
Eur.Phys.J. C36 (2004) 43-48
10.1140/epjc/s2004-01873-6
LU-ITP-2003/026
hep-ph
null
The large $t$ behaviour of the helicity amplitudes of diffractive photoproduction is estimated relying on models of the photon and meson light-cone wave functions and on the double-logarithmic approximation to the exchanged gluon interaction. The role of large-size colour dipole contributions to the photon-meson transition impact factor is discussed.
[ { "created": "Thu, 6 Nov 2003 13:09:51 GMT", "version": "v1" }, { "created": "Tue, 4 May 2004 13:55:57 GMT", "version": "v2" } ]
2016-02-18
[ [ "Ivanov", "A.", "" ], [ "Kirschner", "R.", "" ] ]
The large $t$ behaviour of the helicity amplitudes of diffractive photoproduction is estimated relying on models of the photon and meson light-cone wave functions and on the double-logarithmic approximation to the exchanged gluon interaction. The role of large-size colour dipole contributions to the photon-meson transition impact factor is discussed.
hep-ph/0105069
Joanne Gillett
V. A. Khoze (IPPP Durham)
Comment on an invisible Higgs boson and 50 GeV neutrino
1 page, Latex
null
null
null
hep-ph
null
It has been recently suggested in hep-ph/9911535 and hep-ph/0006324 that the fourth generation of leptons and quarks is not excluded by the precision Z-boson measurements, provided that the mass of the fourth neutrino is around 50 GeV and that its mixing with the neutrinos of the first three generations is negligibly small. We would like to note that in this case the decay rate of the Standard Model Higgs boson into the pair of such neutrinos would be about two orders of magnitude higher than than the Higgs to b-bbar rate. Thus, the predominant decay mode of the Higgs would be invisible, which would require a special strategy for its searches.
[ { "created": "Tue, 8 May 2001 08:41:24 GMT", "version": "v1" }, { "created": "Fri, 11 May 2001 08:46:16 GMT", "version": "v2" } ]
2007-05-23
[ [ "Khoze", "V. A.", "", "IPPP Durham" ] ]
It has been recently suggested in hep-ph/9911535 and hep-ph/0006324 that the fourth generation of leptons and quarks is not excluded by the precision Z-boson measurements, provided that the mass of the fourth neutrino is around 50 GeV and that its mixing with the neutrinos of the first three generations is negligibly small. We would like to note that in this case the decay rate of the Standard Model Higgs boson into the pair of such neutrinos would be about two orders of magnitude higher than than the Higgs to b-bbar rate. Thus, the predominant decay mode of the Higgs would be invisible, which would require a special strategy for its searches.
1712.00445
David Kaiser
Mohammad Hossein Namjoo, Alan H. Guth, and David I. Kaiser
Relativistic Corrections to Nonrelativistic Effective Field Theories
31pp. References added, and 3 appendices added, showing (a) how to implement the field redefinition as a canonical transformation, (b) how to develop the effective field theory using a local field redefinition, and (c) how to use a further field redefinition to compare our results with those of Mukaida, Takimoto, and Yamada
Phys. Rev. D 98, 016011 (2018)
10.1103/PhysRevD.98.016011
MIT-CTP/4955
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we develop a formalism for studying the nonrelativistic limit of relativistic field theories in a systematic way. By introducing a simple, nonlocal field redefinition, we transform a given relativistic theory, describing a real, self-interacting scalar field, into an equivalent theory, describing a complex scalar field that encodes at each time both the original field and its conjugate momentum. Our low-energy effective theory incorporates relativistic corrections to the kinetic energy as well as the backreaction of fast-oscillating terms on the behavior of the dominant, slowly varying component of the field. Possible applications of our new approach include axion dark matter, though the methods developed here should be applicable to the low-energy limits of other field theories as well.
[ { "created": "Fri, 1 Dec 2017 18:59:11 GMT", "version": "v1" }, { "created": "Wed, 13 Jun 2018 12:20:19 GMT", "version": "v2" } ]
2018-07-25
[ [ "Namjoo", "Mohammad Hossein", "" ], [ "Guth", "Alan H.", "" ], [ "Kaiser", "David I.", "" ] ]
In this paper we develop a formalism for studying the nonrelativistic limit of relativistic field theories in a systematic way. By introducing a simple, nonlocal field redefinition, we transform a given relativistic theory, describing a real, self-interacting scalar field, into an equivalent theory, describing a complex scalar field that encodes at each time both the original field and its conjugate momentum. Our low-energy effective theory incorporates relativistic corrections to the kinetic energy as well as the backreaction of fast-oscillating terms on the behavior of the dominant, slowly varying component of the field. Possible applications of our new approach include axion dark matter, though the methods developed here should be applicable to the low-energy limits of other field theories as well.
1410.7915
Alexandra Dobrynina
Alexandra A. Dobrynina, Nicolay V. Mikheev, Georg G. Raffelt
Radiative decay of keV-mass sterile neutrinos in a strongly magnetized plasma
9 pages, 4 figures. Presentation streamlined, results unchanged. Corresponds to version published in PRD
Phys. Rev. D 90, 113015 (2014)
10.1103/PhysRevD.90.113015
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The radiative decay of sterile neutrinos with typical masses of 10 keV is investigated in the presence of a strong magnetic field and degenerate plasma. Full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and non-relativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the un-magnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.
[ { "created": "Wed, 29 Oct 2014 09:45:08 GMT", "version": "v1" }, { "created": "Wed, 7 Jan 2015 12:19:13 GMT", "version": "v2" } ]
2015-01-14
[ [ "Dobrynina", "Alexandra A.", "" ], [ "Mikheev", "Nicolay V.", "" ], [ "Raffelt", "Georg G.", "" ] ]
The radiative decay of sterile neutrinos with typical masses of 10 keV is investigated in the presence of a strong magnetic field and degenerate plasma. Full account is taken of the strongly modified photon dispersion relation relative to vacuum. The limiting cases of relativistic and non-relativistic plasma are analyzed. The decay rate in a strongly magnetized plasma as a function of the electron number density is compared with the un-magnetized case. We find that a strong magnetic field suppresses the catalyzing influence of the plasma on the decay rate.
2205.14513
Roberto Maluf
M. C. Ara\'ujo and R. V. Maluf
Meson scattering in a Lorentz-violating scalar QED at finite temperature
13 pages, 1 figure, minor changes to match published version, references added
ANNALS OF PHYSICS, v. 444, p. 169036, 2022
10.1016/j.aop.2022.169036
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
This paper investigates how the nonzero temperature affects the differential cross-section for mesons scattering in a Lorentz-violating extension of the scalar electrodynamics. We initially discuss some features of the model and extract the zero temperature Feynman rules. Temperature effects are introduced using the Thermo Field Dynamics (TFD) formalism. It is shown that the corrections induced on the meson scattering are very large in the high-temperature regime. Furthermore, our results also suggest that temperature effects may contribute to new constraints on the Lorentz-violating parameters.
[ { "created": "Sat, 28 May 2022 19:46:21 GMT", "version": "v1" }, { "created": "Thu, 2 Jun 2022 17:29:42 GMT", "version": "v2" }, { "created": "Sun, 7 Aug 2022 13:08:09 GMT", "version": "v3" } ]
2022-08-09
[ [ "Araújo", "M. C.", "" ], [ "Maluf", "R. V.", "" ] ]
This paper investigates how the nonzero temperature affects the differential cross-section for mesons scattering in a Lorentz-violating extension of the scalar electrodynamics. We initially discuss some features of the model and extract the zero temperature Feynman rules. Temperature effects are introduced using the Thermo Field Dynamics (TFD) formalism. It is shown that the corrections induced on the meson scattering are very large in the high-temperature regime. Furthermore, our results also suggest that temperature effects may contribute to new constraints on the Lorentz-violating parameters.
2112.06975
Bowen Xiao
Yu Shi, Lei Wang, Shu-Yi Wei, Bo-Wen Xiao
Pursuing the Precision Study for Color Glass Condensate in Forward Hadron Productions
7 pages (main text) plus 35 pages (supplemental material), 20 figures; v2, minor addition
null
10.1103/PhysRevLett.128.202302
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With the tremendous accomplishments of RHIC and the LHC experiments and the advent of the future Electron-Ion Collider on the horizon, the quest for compelling evidence of the color glass condensate (CGC) has become one of the most aspiring goals in the high energy Quantum Chromodynamics research. Pursuing this question requires developing the precision test of the CGC formalism. By systematically implementing the threshold resummation, we significantly improve the stability of the next-to-leading-order calculation in CGC for forward rapidity hadron productions in $pp$ and $pA$ collisions, especially in the high $p_T$ region, and obtain reliable descriptions of all existing data measured at RHIC and the LHC across all $p_T$ regions. Consequently, this technique can pave the way for the precision studies of the CGC next-to-leading-order predictions by confronting them with a large amount of precise data.
[ { "created": "Mon, 13 Dec 2021 19:21:35 GMT", "version": "v1" }, { "created": "Wed, 5 Jan 2022 17:35:57 GMT", "version": "v2" } ]
2022-06-01
[ [ "Shi", "Yu", "" ], [ "Wang", "Lei", "" ], [ "Wei", "Shu-Yi", "" ], [ "Xiao", "Bo-Wen", "" ] ]
With the tremendous accomplishments of RHIC and the LHC experiments and the advent of the future Electron-Ion Collider on the horizon, the quest for compelling evidence of the color glass condensate (CGC) has become one of the most aspiring goals in the high energy Quantum Chromodynamics research. Pursuing this question requires developing the precision test of the CGC formalism. By systematically implementing the threshold resummation, we significantly improve the stability of the next-to-leading-order calculation in CGC for forward rapidity hadron productions in $pp$ and $pA$ collisions, especially in the high $p_T$ region, and obtain reliable descriptions of all existing data measured at RHIC and the LHC across all $p_T$ regions. Consequently, this technique can pave the way for the precision studies of the CGC next-to-leading-order predictions by confronting them with a large amount of precise data.
2208.11896
Hiroyuki Umeeda Dr.
Hiroyuki Umeeda
Is right-handed current contribution to $\bar{B}\to X_ul\nu$ decays corrected by non-trivial vacuum in QCD?
19 pages, 2 figures, 2 tables; v3: matches the version published in PRD
Phys. Rev. D 106, 114034 (2022)
10.1103/PhysRevD.106.114034
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study violation of quark-hadron duality for $\bar{B}\to X_ul\nu$ and $D\to X_dl\nu$ decays in the presence of the right-handed current operator. For this case, we show that duality violation has some aspects different from the standard model due to the existence of an instanton. In particular, the fermionic zero mode of an intermediate light quark can give a nonvanishing contribution owing to its chirality structure. A duality-violating component that arises from a single instanton is then analytically extracted as a finite-distance singularity, leading to an oscillatory correction to the observable in Minkowski space. Finally, we show that the size of duality violation for the lepton energy distribution in $\bar{B}$ decays can be comparable to the chirally suppressed perturbative contribution although the absolute size depends on the detail of the QCD vacuum.
[ { "created": "Thu, 25 Aug 2022 06:57:09 GMT", "version": "v1" }, { "created": "Mon, 29 Aug 2022 03:23:22 GMT", "version": "v2" }, { "created": "Sat, 31 Dec 2022 01:43:48 GMT", "version": "v3" } ]
2023-01-03
[ [ "Umeeda", "Hiroyuki", "" ] ]
We study violation of quark-hadron duality for $\bar{B}\to X_ul\nu$ and $D\to X_dl\nu$ decays in the presence of the right-handed current operator. For this case, we show that duality violation has some aspects different from the standard model due to the existence of an instanton. In particular, the fermionic zero mode of an intermediate light quark can give a nonvanishing contribution owing to its chirality structure. A duality-violating component that arises from a single instanton is then analytically extracted as a finite-distance singularity, leading to an oscillatory correction to the observable in Minkowski space. Finally, we show that the size of duality violation for the lepton energy distribution in $\bar{B}$ decays can be comparable to the chirally suppressed perturbative contribution although the absolute size depends on the detail of the QCD vacuum.
hep-ph/0509188
Alexandre Deur
A. Deur
The strong coupling constant at low Q^2
6 pages, Contribution to the proceedings of the First Workshop on Quark-Hadron Duality and the Transition to pQCD (Duality05, Frascati, June 6-8 2005)
null
10.1142/9789812774132_0007
JLAB-PHY-05-412
hep-ph hep-ex nucl-ex
null
We extract an effective strong coupling constant using low-Q^2 data and sum rules. Its behavior is established over the full Q^2-range and is compared to calculations based on lattice QCD, Schwinger-Dyson equations and a quark model. Although the connection between all these quantities is not known yet, the results are surprisingly alike. Such a similitude may be related to quark-hadron duality.
[ { "created": "Mon, 19 Sep 2005 12:48:48 GMT", "version": "v1" } ]
2017-08-23
[ [ "Deur", "A.", "" ] ]
We extract an effective strong coupling constant using low-Q^2 data and sum rules. Its behavior is established over the full Q^2-range and is compared to calculations based on lattice QCD, Schwinger-Dyson equations and a quark model. Although the connection between all these quantities is not known yet, the results are surprisingly alike. Such a similitude may be related to quark-hadron duality.
0909.2543
Michal Malinsky
Michal Malinsky
Intermediate scales in non-supersymmetric SO(10) grand unified theories
Submitted to the proceedings of the 2009 Europhysics Conference on High Energy Physics, July 16 - 22, 2009, Krakow, Poland
PoS EPS-HEP2009:384,2009
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is often argued that in the class of non-supersymmetric SO(10) grand unified theories there is barely any room for reconciling the lower bound on the position of the GUT scale emerging from the proton decay searches and the lower limit on the absolute neutrino mass scale derived from the neutrino oscillation experiments with the gauge coupling unification constraints. The recent two-loop reassessment of the gauge running provides the first complete picture of the situation, complementing the existing studies in several aspects. The improved analysis reveals a new room in the parametric space that could support a class of non-supersymmetric SO(10) models potentially compatible with all current physical data, including constraints on the relevant Yukawa sector emerging from the quark and lepton masses and mixings. This, in turn, brings back the question of viability of some of the simplest non-supersymmetric GUT scenarios.
[ { "created": "Mon, 14 Sep 2009 13:12:13 GMT", "version": "v1" } ]
2014-11-20
[ [ "Malinsky", "Michal", "" ] ]
It is often argued that in the class of non-supersymmetric SO(10) grand unified theories there is barely any room for reconciling the lower bound on the position of the GUT scale emerging from the proton decay searches and the lower limit on the absolute neutrino mass scale derived from the neutrino oscillation experiments with the gauge coupling unification constraints. The recent two-loop reassessment of the gauge running provides the first complete picture of the situation, complementing the existing studies in several aspects. The improved analysis reveals a new room in the parametric space that could support a class of non-supersymmetric SO(10) models potentially compatible with all current physical data, including constraints on the relevant Yukawa sector emerging from the quark and lepton masses and mixings. This, in turn, brings back the question of viability of some of the simplest non-supersymmetric GUT scenarios.
2404.04016
Kan Chen
Kan Chen and Bo Wang
Flavor-spin symmetry of the $P^N_{\psi}/H_{\Omega_{ccc}}^N$ and $P^\Lambda_{\psi s}/H^{\Lambda}_{\Omega_{ccc}s}$ molecular states
17 pages, 10 tables, 4 figures
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Based on a contact lagrangian that incorporates the SU(3) flavor and SU(2) spin symmetries, we discuss the symmetry properties of the interactions among the heavy flavor meson-baryon $P_{\psi}^N$, $P_{\psi s}^\Lambda$ (with quark components [$n\bar{c}$][$nnc$], [$s\bar{c}$][$nnc$], or [$n\bar{c}$][$nsc$]) systems and di-baryon $H_{\Omega_{ccc}}^N$, $H^{\Lambda}_{\Omega_{ccc}s}$ (with quark components [$nnc$][$ncc$], [$nnc$][$scc$] or [$nsc$][$ncc$]) systems ($n=u$, $d$). The light quark components of the $P_{\psi}^N$ ($P_{\psi s}^\Lambda$) and $H_{\Omega_{ccc}}^N$ ($H_{\Omega_{ccc}s}^\Lambda$) systems have identical flavors, the interactions generated from the exchanges of light mesons in the $P_{\psi}^N$ ($P^\Lambda_{\psi s}$) systems should be very similar to that of the $H_{\Omega_{ccc}}^N$ ($H^{\Lambda}_{\Omega_{ccc}s}$) systems. We perform the single-channel and multi-channel calculations on the $P_{\psi}^N/P^\Lambda_{\psi s}/H_{\Omega_{ccc}}^N/H^{\Lambda}_{\Omega_{ccc}s}$ systems and introduce the SU(3) breaking effect to identify the different mass spectra among the $P_{\psi}^N$ ($H_{\Omega_{ccc}}^N$) and $P^\Lambda_{\psi s}$ ($H^{\Lambda}_{\Omega_{ccc}s}$) systems. We suggest two kinds of evidences for the existence of the flavor-spin symmetry among the heavy flavor $P_{\psi}^N/H_{\Omega_{ccc}}^N/P^\Lambda_{\psi s}/H^{\Lambda}_{\Omega_{ccc}s}$ molecule community, i.e., the mass arrangements of the $P_{\psi}^N/H_{\Omega_{ccc}}^N/P^\Lambda_{\psi s}/H^{\Lambda}_{\Omega_{ccc}s}$ mass spectra and the binding energies of the heavy flavor meson-baryon (di-baryon) systems attributed to the same contact potentials.
[ { "created": "Fri, 5 Apr 2024 10:58:17 GMT", "version": "v1" } ]
2024-04-08
[ [ "Chen", "Kan", "" ], [ "Wang", "Bo", "" ] ]
Based on a contact lagrangian that incorporates the SU(3) flavor and SU(2) spin symmetries, we discuss the symmetry properties of the interactions among the heavy flavor meson-baryon $P_{\psi}^N$, $P_{\psi s}^\Lambda$ (with quark components [$n\bar{c}$][$nnc$], [$s\bar{c}$][$nnc$], or [$n\bar{c}$][$nsc$]) systems and di-baryon $H_{\Omega_{ccc}}^N$, $H^{\Lambda}_{\Omega_{ccc}s}$ (with quark components [$nnc$][$ncc$], [$nnc$][$scc$] or [$nsc$][$ncc$]) systems ($n=u$, $d$). The light quark components of the $P_{\psi}^N$ ($P_{\psi s}^\Lambda$) and $H_{\Omega_{ccc}}^N$ ($H_{\Omega_{ccc}s}^\Lambda$) systems have identical flavors, the interactions generated from the exchanges of light mesons in the $P_{\psi}^N$ ($P^\Lambda_{\psi s}$) systems should be very similar to that of the $H_{\Omega_{ccc}}^N$ ($H^{\Lambda}_{\Omega_{ccc}s}$) systems. We perform the single-channel and multi-channel calculations on the $P_{\psi}^N/P^\Lambda_{\psi s}/H_{\Omega_{ccc}}^N/H^{\Lambda}_{\Omega_{ccc}s}$ systems and introduce the SU(3) breaking effect to identify the different mass spectra among the $P_{\psi}^N$ ($H_{\Omega_{ccc}}^N$) and $P^\Lambda_{\psi s}$ ($H^{\Lambda}_{\Omega_{ccc}s}$) systems. We suggest two kinds of evidences for the existence of the flavor-spin symmetry among the heavy flavor $P_{\psi}^N/H_{\Omega_{ccc}}^N/P^\Lambda_{\psi s}/H^{\Lambda}_{\Omega_{ccc}s}$ molecule community, i.e., the mass arrangements of the $P_{\psi}^N/H_{\Omega_{ccc}}^N/P^\Lambda_{\psi s}/H^{\Lambda}_{\Omega_{ccc}s}$ mass spectra and the binding energies of the heavy flavor meson-baryon (di-baryon) systems attributed to the same contact potentials.
1301.0453
Jinmian Li
Zhaofeng Kang, Jinmian Li, Tianjun Li, Da Liu, Jing Shu
Probing the CP-even Higgs Sector via $H_3\to H_2H_1$ in the Natural NMSSM
5 pages, 2 figures. Some typos corrected and reference added
null
10.1103/PhysRevD.88.015006
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
After the discovery of a Standard Model (SM) like Higgs boson, naturalness strongly favors the next to the Minimal Supersymmetric SM (NMSSM). In this letter, we point out that the most natural NMSSM predicts the following CP-even Higgs $H_i$ sector: (A) $H_2$ is the SM-like Higgs boson with mass pushed-upward by a lighter $H_1$ with mass overwhelmingly within $[m_{H_2}/2,m_{H_2}]$; (B) $m_{H_3}\simeq 2\mu/\sin2\beta\gtrsim300$ GeV; (C) $H_3$ has a significant coupling to top quarks and can decay to $H_1H_2$ with a large branching ratio. Using jet substructure we show that all the three Higgs bosons can be discovered via $gg\to H_3 \to H_1H_2\to b\bar b \ell\nu jj$ at the 14 TeV LHC. Especially, the LEP-LHC scenario with $H_1\simeq98$ GeV has a very good discovery potential.
[ { "created": "Thu, 3 Jan 2013 13:36:50 GMT", "version": "v1" }, { "created": "Fri, 22 Feb 2013 05:22:56 GMT", "version": "v2" } ]
2013-08-09
[ [ "Kang", "Zhaofeng", "" ], [ "Li", "Jinmian", "" ], [ "Li", "Tianjun", "" ], [ "Liu", "Da", "" ], [ "Shu", "Jing", "" ] ]
After the discovery of a Standard Model (SM) like Higgs boson, naturalness strongly favors the next to the Minimal Supersymmetric SM (NMSSM). In this letter, we point out that the most natural NMSSM predicts the following CP-even Higgs $H_i$ sector: (A) $H_2$ is the SM-like Higgs boson with mass pushed-upward by a lighter $H_1$ with mass overwhelmingly within $[m_{H_2}/2,m_{H_2}]$; (B) $m_{H_3}\simeq 2\mu/\sin2\beta\gtrsim300$ GeV; (C) $H_3$ has a significant coupling to top quarks and can decay to $H_1H_2$ with a large branching ratio. Using jet substructure we show that all the three Higgs bosons can be discovered via $gg\to H_3 \to H_1H_2\to b\bar b \ell\nu jj$ at the 14 TeV LHC. Especially, the LEP-LHC scenario with $H_1\simeq98$ GeV has a very good discovery potential.
1502.01113
Harleen Dahiya Dr.
Narinder Kumar and Harleen Dahiya
Transverse distortion of a relativistic composite system in impact parameter space
17 pages, 6 figures. To appear in Eur. Phys. J. A. arXiv admin note: text overlap with arXiv:1410.3225
Eur. Phys. J. A51 (2015) 19
10.1140/epja/i2015-15019-x
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the Generalized Parton Distributions (GPDs) in impact parameter space using the explicit light front wave functions (LFWFs) for the two-particle Fock state of the electron in QED. The Fourier transform (FT) of the GPDs gives the distribution of quarks in the transverse plane for zero longitudinal momentum transfer ($\xi=0$). We study the relationship of the spin flip GPD $E(x,0,-\vec{\Delta}_\perp^2)$ with the distortion of unpolarized quark distribution in the transverse plane when the target nucleon is transversely polarized and also determine the sign of distortion from the sign of anomalous magnetic moment. To verify the sign of distortion, we also compute it directly from the LFWFs by performing a FT in position space coordinate $\vec{f}_\perp$. The explicit relation between the deformation in the two spaces can also be obtained using the convolution integrals. To show the relation of the model LFWFs to a realistic model of nucleon physics, we have designed a specific weight function of our model LFWFs and integrated it over the mass parameter. Also we have simulated the form factor of the nucleon in the AdS/QCD holographic LFWFs model and studied the power-law behaviour at short distances.
[ { "created": "Wed, 4 Feb 2015 07:48:18 GMT", "version": "v1" } ]
2015-06-23
[ [ "Kumar", "Narinder", "" ], [ "Dahiya", "Harleen", "" ] ]
We investigate the Generalized Parton Distributions (GPDs) in impact parameter space using the explicit light front wave functions (LFWFs) for the two-particle Fock state of the electron in QED. The Fourier transform (FT) of the GPDs gives the distribution of quarks in the transverse plane for zero longitudinal momentum transfer ($\xi=0$). We study the relationship of the spin flip GPD $E(x,0,-\vec{\Delta}_\perp^2)$ with the distortion of unpolarized quark distribution in the transverse plane when the target nucleon is transversely polarized and also determine the sign of distortion from the sign of anomalous magnetic moment. To verify the sign of distortion, we also compute it directly from the LFWFs by performing a FT in position space coordinate $\vec{f}_\perp$. The explicit relation between the deformation in the two spaces can also be obtained using the convolution integrals. To show the relation of the model LFWFs to a realistic model of nucleon physics, we have designed a specific weight function of our model LFWFs and integrated it over the mass parameter. Also we have simulated the form factor of the nucleon in the AdS/QCD holographic LFWFs model and studied the power-law behaviour at short distances.
hep-ph/9802256
James V. Steele
James Steele, Hidenaga Yamagishi, and Ismail Zahed
Electromagnetic Emission Rates and Spectral Sum Rules
4 pages (Latex), 2 embedded ps figures, espcrc1 style, talk given at Quark Matter 97, December 97, Tsukuba, Japan
Nucl.Phys. A638 (1998) 495c-498c
10.1016/S0375-9474(98)00339-X
null
hep-ph
null
The electromagnetic emission rates at SPS energies satisfy spectral constraints in leading order in the pion and nucleon densities. These constraints follow from the strictures of broken chiral symmetry. We saturate these constraints using available data, leading to model independent emission rates from a hadronic gas. With a simple fire-ball scenario, only large nucleon densities may account for the present CERES data.
[ { "created": "Thu, 5 Feb 1998 16:24:16 GMT", "version": "v1" } ]
2009-10-31
[ [ "Steele", "James", "" ], [ "Yamagishi", "Hidenaga", "" ], [ "Zahed", "Ismail", "" ] ]
The electromagnetic emission rates at SPS energies satisfy spectral constraints in leading order in the pion and nucleon densities. These constraints follow from the strictures of broken chiral symmetry. We saturate these constraints using available data, leading to model independent emission rates from a hadronic gas. With a simple fire-ball scenario, only large nucleon densities may account for the present CERES data.
1411.7319
Elmar Biernat P
Elmar P. Biernat, M. T. Pe\~na, J. E. Ribeiro, Alfred Stadler, Franz Gross
Chiral-symmetry breaking and confinement in Minkowski space
6 pages, 4 figures; prepared for conference "XIth Quark Confinement and the Hadron Spectrum", Saint-Petersburg, Russia, September 8-12, 2014
AIP Conf. Proc. 1701, 040003 (2016)
10.1063/1.4938620
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a model for the quark-antiquark interaction formulated in Minkowski space using the Covariant Spectator Theory. The quark propagators are dressed with the same kernel that describes the interaction between different quarks. By applying the axial-vector Ward-Takahashi identity we show that our model satisfies the Adler-zero constraint imposed by chiral symmetry. For this model, our Minkowski-space results of the dressed quark mass function are compared to lattice QCD data obtained in Euclidean space. The mass function is then used in the calculation of the electromagnetic pion form factor in relativistic impulse approximation, and the results are presented and compared with the experimental data from JLab.
[ { "created": "Wed, 26 Nov 2014 18:05:49 GMT", "version": "v1" } ]
2016-01-29
[ [ "Biernat", "Elmar P.", "" ], [ "Peña", "M. T.", "" ], [ "Ribeiro", "J. E.", "" ], [ "Stadler", "Alfred", "" ], [ "Gross", "Franz", "" ] ]
We present a model for the quark-antiquark interaction formulated in Minkowski space using the Covariant Spectator Theory. The quark propagators are dressed with the same kernel that describes the interaction between different quarks. By applying the axial-vector Ward-Takahashi identity we show that our model satisfies the Adler-zero constraint imposed by chiral symmetry. For this model, our Minkowski-space results of the dressed quark mass function are compared to lattice QCD data obtained in Euclidean space. The mass function is then used in the calculation of the electromagnetic pion form factor in relativistic impulse approximation, and the results are presented and compared with the experimental data from JLab.
hep-ph/0011347
Pankaj Agrawal
Pankaj Agrawal
Prospects of Discovering the Higgs Boson at the Tevatron
12 pages
Mod.Phys.Lett. A16 (2001) 897-906
10.1142/S0217732301004054
IP/BBSR/2000-10
hep-ph
null
We carry out an event generator based study to evaluate the usefulness of the the exclusive signature ``$e^\pm (\mu^\pm) + 2$ bottom jets'' in discovering the Higgs boson at the Tevatron. Using an event generator, we show that with enough luminosity, one should be able to detect the Higgs boson up to the mass of about 130 GeV. We consider a slightly modified version of the above signature that includes one extra jet. This new signature is more useful because it increases the number of signal events significantly.
[ { "created": "Tue, 28 Nov 2000 14:44:25 GMT", "version": "v1" } ]
2016-09-06
[ [ "Agrawal", "Pankaj", "" ] ]
We carry out an event generator based study to evaluate the usefulness of the the exclusive signature ``$e^\pm (\mu^\pm) + 2$ bottom jets'' in discovering the Higgs boson at the Tevatron. Using an event generator, we show that with enough luminosity, one should be able to detect the Higgs boson up to the mass of about 130 GeV. We consider a slightly modified version of the above signature that includes one extra jet. This new signature is more useful because it increases the number of signal events significantly.
1207.6876
Jeonghyeon Song
Sanghyeon Chang, Kang Young Lee, So Young Shim and Jeonghyeon Song
Direct bound on the minimal Universal Extra Dimension model from the $t\bar{t}$ resonance search at the Tevatron
referenced minor corrections added; 13 pages with 4 figures
null
10.1103/PhysRevD.86.117503
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the minimal Universal Extra Dimension (mUED) model, the second Kaluza-Klein (KK) gluon $g^{(2)}$ has loop-induced vertices with the standard model quarks, mediated by the first KK modes of the quark and the gluon/Higgs boson. With a top quark pair, this vertex is enhanced by the cooperation of the strong coupling of a gluon and the large Yukawa coupling of a top quark, leading to substantial branching ratio of $Br(g^{(2)} \to t \bar{t}) \approx 7%-8%$. As the $g^{(2)}$ coupling with two gluons appears via dimension-6 operator, $q\bar{q}\to g^{(2)}\to t\bar{t}$ is the golden mode for the mUED model. Hence the best channel is the $t\bar{t}$ resonance search in $p\bar{p}$ collisions. The recent Tevatron data at $\sqrt{s}=1.96$ TeV with an integrated luminosity of 8.7 fb$^{-1}$ are shown to give the first direct bound on the $g^{(2)}$ mass above 800 GeV. The implication and future prospect at the LHC are discussed also.
[ { "created": "Mon, 30 Jul 2012 09:39:49 GMT", "version": "v1" }, { "created": "Wed, 8 Aug 2012 11:07:56 GMT", "version": "v2" }, { "created": "Sat, 11 Aug 2012 09:22:04 GMT", "version": "v3" } ]
2013-05-30
[ [ "Chang", "Sanghyeon", "" ], [ "Lee", "Kang Young", "" ], [ "Shim", "So Young", "" ], [ "Song", "Jeonghyeon", "" ] ]
In the minimal Universal Extra Dimension (mUED) model, the second Kaluza-Klein (KK) gluon $g^{(2)}$ has loop-induced vertices with the standard model quarks, mediated by the first KK modes of the quark and the gluon/Higgs boson. With a top quark pair, this vertex is enhanced by the cooperation of the strong coupling of a gluon and the large Yukawa coupling of a top quark, leading to substantial branching ratio of $Br(g^{(2)} \to t \bar{t}) \approx 7%-8%$. As the $g^{(2)}$ coupling with two gluons appears via dimension-6 operator, $q\bar{q}\to g^{(2)}\to t\bar{t}$ is the golden mode for the mUED model. Hence the best channel is the $t\bar{t}$ resonance search in $p\bar{p}$ collisions. The recent Tevatron data at $\sqrt{s}=1.96$ TeV with an integrated luminosity of 8.7 fb$^{-1}$ are shown to give the first direct bound on the $g^{(2)}$ mass above 800 GeV. The implication and future prospect at the LHC are discussed also.
hep-ph/0207310
Gerhard Ecker
V. Cirigliano, G. Ecker, H. Neufeld
Radiative tau decay and the magnetic moment of the muon
24 pages, 6 figures
JHEP 0208 (2002) 002
10.1088/1126-6708/2002/08/002
IFIC/02-32, UWThPh-2002-16
hep-ph
null
We discuss the decay tau^- -> nu_tau pi^- pi^0 gamma in terms of a model with the correct low-energy structure and with the relevant resonance degress of freedom. The nontrivial radiative dynamics becomes visible for large photon momenta only. We use the model to calculate electromagnetic corrections for the two-pion contribution to hadronic vacuum polarization extracted from photon-inclusive two-pion decays. The corrections are insensitive to the details of the model and depend on the pion form factor only. Putting all relevant isospin violating corrections together, we obtain a shift Delta a_mu = (- 120 +/- 26 +/- 3) x 10^-11 to be applied to determinations of the anomalous magnetic moment of the muon from photon-inclusive tau data.
[ { "created": "Thu, 25 Jul 2002 12:25:35 GMT", "version": "v1" }, { "created": "Mon, 19 Aug 2002 09:22:54 GMT", "version": "v2" } ]
2009-11-07
[ [ "Cirigliano", "V.", "" ], [ "Ecker", "G.", "" ], [ "Neufeld", "H.", "" ] ]
We discuss the decay tau^- -> nu_tau pi^- pi^0 gamma in terms of a model with the correct low-energy structure and with the relevant resonance degress of freedom. The nontrivial radiative dynamics becomes visible for large photon momenta only. We use the model to calculate electromagnetic corrections for the two-pion contribution to hadronic vacuum polarization extracted from photon-inclusive two-pion decays. The corrections are insensitive to the details of the model and depend on the pion form factor only. Putting all relevant isospin violating corrections together, we obtain a shift Delta a_mu = (- 120 +/- 26 +/- 3) x 10^-11 to be applied to determinations of the anomalous magnetic moment of the muon from photon-inclusive tau data.
hep-ph/9709329
Carlos Munoz
Carlos Munoz
Charge and Color Breaking in Supersymmetry and Superstrings
Based on talks given at "Beyond the desert: accelerator and non-accelerator approaches", Castle Ringberg, Tegernsee (Germany), June 1997; "8th Miniworshop on Particle and Astroparticle Physics", Pusan (South Korea), May 1997. Uuencoded LaTex file. 11 pages + macro iopconf1.sty + 1 Postscript figure, including the macro psfig.tex
null
null
KAIST-TH 97/16, FTUAM 97/20
hep-ph hep-th
null
Charge and color breaking minima in SUSY theories might make the standard vacuum unstable. In this talk a brief review of this issue is performed. When a complete analysis of all the potentially dangerous directions in the field space of the theory is carried out, imposing that the standard vacuum should be the global minimum, the corresponding constraints turn out to be very strong and, in fact, there are extensive regions in the parameter space of soft SUSY--breaking terms that become forbidden. For instance, in the context of the MSSM with universal soft terms, this produces important bounds, not only on the value of A, but also on the values of B, M and m. In specific SUSY scenarios, as fixed point models, no-scale supergravity, gauge-mediated SUSY breaking and superstrings, the charge and color breaking constraints are also very important. For example, if the dilaton is the source of SUSY breaking in four-dimensional superstrings, the whole parameter space (m_{3/2},B) is excluded on these grounds. Cosmological analyses are also briefly reviewed.
[ { "created": "Fri, 12 Sep 1997 14:58:09 GMT", "version": "v1" } ]
2007-05-23
[ [ "Munoz", "Carlos", "" ] ]
Charge and color breaking minima in SUSY theories might make the standard vacuum unstable. In this talk a brief review of this issue is performed. When a complete analysis of all the potentially dangerous directions in the field space of the theory is carried out, imposing that the standard vacuum should be the global minimum, the corresponding constraints turn out to be very strong and, in fact, there are extensive regions in the parameter space of soft SUSY--breaking terms that become forbidden. For instance, in the context of the MSSM with universal soft terms, this produces important bounds, not only on the value of A, but also on the values of B, M and m. In specific SUSY scenarios, as fixed point models, no-scale supergravity, gauge-mediated SUSY breaking and superstrings, the charge and color breaking constraints are also very important. For example, if the dilaton is the source of SUSY breaking in four-dimensional superstrings, the whole parameter space (m_{3/2},B) is excluded on these grounds. Cosmological analyses are also briefly reviewed.
hep-ph/9501332
Michael Meyer-Hermann
M. Meyer-Hermann, A. Sch\"afer and W. Greiner
QCD sum rules with finite masses
15 pages, including two pictures to be found in an extra file. Latex neads epsf.sty
null
10.1007/BF01290918
UFTP-379/1995
hep-ph
null
The concept of QCD sum rules is extended to bound states composed of particles with finite mass such as scalar quarks or strange quarks. It turns out that mass corrections become important in this context. The number of relevant corrections is analyzed in a systematic discussion of the IR- and UV-divergencies, leading in general to a finite number of corrections. The results are demonstrated for a system of two massless quarks and two heavy scalar quarks.
[ { "created": "Wed, 18 Jan 1995 14:18:00 GMT", "version": "v1" }, { "created": "Thu, 19 Jan 1995 13:52:00 GMT", "version": "v2" } ]
2015-06-25
[ [ "Meyer-Hermann", "M.", "" ], [ "Schäfer", "A.", "" ], [ "Greiner", "W.", "" ] ]
The concept of QCD sum rules is extended to bound states composed of particles with finite mass such as scalar quarks or strange quarks. It turns out that mass corrections become important in this context. The number of relevant corrections is analyzed in a systematic discussion of the IR- and UV-divergencies, leading in general to a finite number of corrections. The results are demonstrated for a system of two massless quarks and two heavy scalar quarks.
hep-ph/9807507
He Xiao-Gang
Xiao-Gang He and Wei-Shu Hou
Direct CP Violation in Angular Distribution of $B\to J/\psi K^{*}$ Decays
7 pages, Revtex
Phys.Rev. D58 (1998) 117502
10.1103/PhysRevD.58.117502
null
hep-ph
null
We show that the study of certain observables in the angular distribution in $B\to J/\psi K^*$ provide clear test for CP vioaltion beyond the Standard Model. These observables vanish in SM, but in models beyond SM some of them can be large enough to be measured at B factories.
[ { "created": "Mon, 27 Jul 1998 07:51:48 GMT", "version": "v1" } ]
2016-09-06
[ [ "He", "Xiao-Gang", "" ], [ "Hou", "Wei-Shu", "" ] ]
We show that the study of certain observables in the angular distribution in $B\to J/\psi K^*$ provide clear test for CP vioaltion beyond the Standard Model. These observables vanish in SM, but in models beyond SM some of them can be large enough to be measured at B factories.