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hep-ph/0203034
Csaba Csaki
Csaba Csaki, Joshua Erlich, and John Terning
The Effective Lagrangian in the Randall-Sundrum Model and Electroweak Physics
16 pages, LaTeX, 1 figure included, uses JHEP.cls, extended introduction, added references
Phys.Rev.D66:064021,2002
10.1103/PhysRevD.66.064021
CLNS 02/1778
hep-ph hep-th
null
We consider the two-brane Randall-Sundrum (RS) model with bulk gauge fields. We carefully match the bulk theory to a 4D low-energy effective Lagrangian. In addition to the four-fermion operators induced by KK exchange we find that large negative S and T parameters are induced in the effective theory. This is a tree-level effect and is a consequence of the shapes of the W and Z wave functions in the bulk. Such effects are generic in extra dimensional theories where the standard model (SM) gauge bosons have non-uniform wave functions along the extra dimension. The corrections to precision electroweak observables in the RS model are mostly dominated by S. We fit the parameters of the RS model to the experimental data and find somewhat stronger bounds than previously obtained; however, the standard model bound on the Higgs mass from precision measurements can only be slightly relaxed in this theory.
[ { "created": "Tue, 5 Mar 2002 20:47:03 GMT", "version": "v1" }, { "created": "Tue, 20 Aug 2002 23:11:20 GMT", "version": "v2" } ]
2010-04-06
[ [ "Csaki", "Csaba", "" ], [ "Erlich", "Joshua", "" ], [ "Terning", "John", "" ] ]
We consider the two-brane Randall-Sundrum (RS) model with bulk gauge fields. We carefully match the bulk theory to a 4D low-energy effective Lagrangian. In addition to the four-fermion operators induced by KK exchange we find that large negative S and T parameters are induced in the effective theory. This is a tree-level effect and is a consequence of the shapes of the W and Z wave functions in the bulk. Such effects are generic in extra dimensional theories where the standard model (SM) gauge bosons have non-uniform wave functions along the extra dimension. The corrections to precision electroweak observables in the RS model are mostly dominated by S. We fit the parameters of the RS model to the experimental data and find somewhat stronger bounds than previously obtained; however, the standard model bound on the Higgs mass from precision measurements can only be slightly relaxed in this theory.
1109.3742
Toshifumi Yamada
Toshifumi Yamada
Observing Signals of the Bulk Matter RS Model through Rare Decays of SUSY Particles
null
Phys.Rev. D85 (2012) 016007
10.1103/PhysRevD.85.016007
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The bulk matter Randall-Sundrum (RS) model is a setup where Standard Model (SM) matter and gauge fields reside in the bulk of 5D warped spacetime while the Higgs field is confined on the IR brane. The wavefunctions of the 1st and 2nd generation matter particles are localized towards the UV brane and those of the 3rd generation towards the IR brane, so that the hierarchical structure of the Yukawa couplings arises geometrically without hierarchy in fundamental parameters. This paper discusses an experimental test of this model in the case where the Kaluza-Klein scale is far above the collider scale, but the model is combined with 5D Minimal SUSY Standard Model (MSSM) and SUSY particles are in the reach of collider experiments. A general SUSY breaking mass spectrum consistent with the bulk matter RS model is considered: SUSY breaking sector locates on the IR brane and its effects are mediated to 5D MSSM through a hybrid of gravity mediation, gaugino mediation and gauge mediation. This paper argues that it is possible to observe the signals of the bulk matter RS model through rare decays of "almost SU(2) singlet mass eigenstates" that are induced by flavor-violating gravity mediation contributions to matter soft SUSY breaking terms.
[ { "created": "Sat, 17 Sep 2011 01:34:08 GMT", "version": "v1" }, { "created": "Wed, 7 Dec 2011 01:45:31 GMT", "version": "v2" } ]
2015-05-30
[ [ "Yamada", "Toshifumi", "" ] ]
The bulk matter Randall-Sundrum (RS) model is a setup where Standard Model (SM) matter and gauge fields reside in the bulk of 5D warped spacetime while the Higgs field is confined on the IR brane. The wavefunctions of the 1st and 2nd generation matter particles are localized towards the UV brane and those of the 3rd generation towards the IR brane, so that the hierarchical structure of the Yukawa couplings arises geometrically without hierarchy in fundamental parameters. This paper discusses an experimental test of this model in the case where the Kaluza-Klein scale is far above the collider scale, but the model is combined with 5D Minimal SUSY Standard Model (MSSM) and SUSY particles are in the reach of collider experiments. A general SUSY breaking mass spectrum consistent with the bulk matter RS model is considered: SUSY breaking sector locates on the IR brane and its effects are mediated to 5D MSSM through a hybrid of gravity mediation, gaugino mediation and gauge mediation. This paper argues that it is possible to observe the signals of the bulk matter RS model through rare decays of "almost SU(2) singlet mass eigenstates" that are induced by flavor-violating gravity mediation contributions to matter soft SUSY breaking terms.
hep-ph/9504247
A. D. Martin
J. Kwiecinski and A.D. Martin
BFKL predictions at small x from k_T and collinear factorization viewpoints
11 LaTeX pages, 1 figure (uuencoded)
Phys.Lett. B353 (1995) 123-130
10.1016/0370-2693(95)00564-2
Durham preprint DTP/95/34
hep-ph
null
Hard scattering processes involving hadrons at small $x$ are described by a $k_T$-factorization formula driven by a BFKL gluon. We explore the equivalence of this description to a collinear-factorization approach in which the anomalous dimensions $\gamma_{gg}$ and $\gamma_{qg}/\alpha_S$ are expressed as power series in $\alpha_S \log (1/x)$, or to be precise $\alpha_S/\omega$ where $\omega$ is the moment index. In particular we confront the collinear-factorization expansion with that extracted from the BFKL approach with running coupling included.
[ { "created": "Thu, 6 Apr 1995 14:30:30 GMT", "version": "v1" } ]
2016-09-01
[ [ "Kwiecinski", "J.", "" ], [ "Martin", "A. D.", "" ] ]
Hard scattering processes involving hadrons at small $x$ are described by a $k_T$-factorization formula driven by a BFKL gluon. We explore the equivalence of this description to a collinear-factorization approach in which the anomalous dimensions $\gamma_{gg}$ and $\gamma_{qg}/\alpha_S$ are expressed as power series in $\alpha_S \log (1/x)$, or to be precise $\alpha_S/\omega$ where $\omega$ is the moment index. In particular we confront the collinear-factorization expansion with that extracted from the BFKL approach with running coupling included.
1606.04113
Rudnei O. Ramos
Arjun Berera, Robert Brandenberger, Joel Mabillard and Rudnei O. Ramos
Stability of the pion string in a thermal and dense medium
16 pages, 6 figures. Replaced with version matching the published one
Phys. Rev. D 94, 065043 (2016)
10.1103/PhysRevD.94.065043
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the stability of the pion string in a thermal bath and a dense medium. We find that stability is dependent on the order of the chiral transition. String core stability within the experimentally allowed regime is found only if the chiral transition is second order, and even there the stable region is small, i.e., the temperature below which the core is unstable is close to the critical temperature of the phase transition. We also find that the presence of a dense medium, in addition to the thermal bath, enhances the experimentally accessible region with stable strings. We also argue that once the string core decays, the "effective winding" of the string persists at large distances from the string core. Our analysis is done both in the chiral limit, which is mainly what has been explored in the literature up to now, and for the physical $h \ne 0$ case, where a conceptual framework is set up for addressing this regime and some simple estimates are done.
[ { "created": "Mon, 13 Jun 2016 20:00:55 GMT", "version": "v1" }, { "created": "Sun, 2 Oct 2016 23:02:28 GMT", "version": "v2" } ]
2016-10-04
[ [ "Berera", "Arjun", "" ], [ "Brandenberger", "Robert", "" ], [ "Mabillard", "Joel", "" ], [ "Ramos", "Rudnei O.", "" ] ]
We investigate the stability of the pion string in a thermal bath and a dense medium. We find that stability is dependent on the order of the chiral transition. String core stability within the experimentally allowed regime is found only if the chiral transition is second order, and even there the stable region is small, i.e., the temperature below which the core is unstable is close to the critical temperature of the phase transition. We also find that the presence of a dense medium, in addition to the thermal bath, enhances the experimentally accessible region with stable strings. We also argue that once the string core decays, the "effective winding" of the string persists at large distances from the string core. Our analysis is done both in the chiral limit, which is mainly what has been explored in the literature up to now, and for the physical $h \ne 0$ case, where a conceptual framework is set up for addressing this regime and some simple estimates are done.
2302.10119
Amitabha Lahiri
Indrajit Ghose, Riya Barick, Amitabha Lahiri
Neutrino oscillation caused by spacetime geometry
Based on talk delivered by Indrajit Ghose at the International Conference on Neutrinos and Dark Matter (NuDM-2022), Sharm El-Sheikh, Egypt, 25-28 September, 2022
Letters in High Energy Physics 2023 (2023) 349
10.31526/lhep.2023.349
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Effects of gravitational interaction are generally neglected in particle physics. A first order formulation of gravity is presented to include gravity in Quantum Mechanical Lagrangian of fermions. It is seen that fermions minimally coupled to gravity gives rise to a torsionless effective theory with a quartic interaction. After passing through a thermal background the most generic form of contortion contributes to neutrino effective mass. This effective mass can change the current oscillation parameters.
[ { "created": "Mon, 20 Feb 2023 17:30:26 GMT", "version": "v1" } ]
2023-03-01
[ [ "Ghose", "Indrajit", "" ], [ "Barick", "Riya", "" ], [ "Lahiri", "Amitabha", "" ] ]
Effects of gravitational interaction are generally neglected in particle physics. A first order formulation of gravity is presented to include gravity in Quantum Mechanical Lagrangian of fermions. It is seen that fermions minimally coupled to gravity gives rise to a torsionless effective theory with a quartic interaction. After passing through a thermal background the most generic form of contortion contributes to neutrino effective mass. This effective mass can change the current oscillation parameters.
hep-ph/0104266
Yi-Fang Wang
Hesheng Chen, Linkai Ding, Jingtang He, Haohuai Kuang, Yusheng Lu, Yuqian Ma, Lianyou Shan, Changquan Shen, Yifang Wang, Changgen Yang, Xinmin Zhang, Qingqi Zhu, Chengrui Qing, Zhaohua Xiong, Jin Min Yang, Zhaoxi Zhang, Jiaer Chen, Yanlin Ye, S.C. Lee, H.T. Wong, Kerry Whisnant, Bing-Lin Young
Prospect of a very long baseline neutrino oscillation experiment: HIPA to Beijing
61 pages, 23 figures
null
null
null
hep-ph
null
We discuss the prospects of a very long baseline neutrino oscillation experiment from HIPA to Beijing. The current understanding of neutrino oscillations, both theoretically and experimentally, are summarized. The figure of merits for interested physics measurements are defined and compared at different distances: 300 km, 700 km, 2100 km and 3000 km. We conclude that a baseline more than 2100 km is optimal. A large water cerenkov calorimeter was proposed and its performance is satisfactory from a Monte Carlo simulation study. Such a large detector can do many other measurements on cosmic-rays physics and astrophysics.
[ { "created": "Wed, 25 Apr 2001 12:42:39 GMT", "version": "v1" }, { "created": "Fri, 4 May 2001 02:08:18 GMT", "version": "v2" } ]
2019-08-17
[ [ "Chen", "Hesheng", "" ], [ "Ding", "Linkai", "" ], [ "He", "Jingtang", "" ], [ "Kuang", "Haohuai", "" ], [ "Lu", "Yusheng", "" ], [ "Ma", "Yuqian", "" ], [ "Shan", "Lianyou", "" ], [ "Shen", "Changquan", "" ], [ "Wang", "Yifang", "" ], [ "Yang", "Changgen", "" ], [ "Zhang", "Xinmin", "" ], [ "Zhu", "Qingqi", "" ], [ "Qing", "Chengrui", "" ], [ "Xiong", "Zhaohua", "" ], [ "Yang", "Jin Min", "" ], [ "Zhang", "Zhaoxi", "" ], [ "Chen", "Jiaer", "" ], [ "Ye", "Yanlin", "" ], [ "Lee", "S. C.", "" ], [ "Wong", "H. T.", "" ], [ "Whisnant", "Kerry", "" ], [ "Young", "Bing-Lin", "" ] ]
We discuss the prospects of a very long baseline neutrino oscillation experiment from HIPA to Beijing. The current understanding of neutrino oscillations, both theoretically and experimentally, are summarized. The figure of merits for interested physics measurements are defined and compared at different distances: 300 km, 700 km, 2100 km and 3000 km. We conclude that a baseline more than 2100 km is optimal. A large water cerenkov calorimeter was proposed and its performance is satisfactory from a Monte Carlo simulation study. Such a large detector can do many other measurements on cosmic-rays physics and astrophysics.
0901.3280
Chia-Min Lin
Chia-Min Lin, Kingman Cheung
Reducing the Spectral Index in Supernatural Inflation
6 pages, 1 figure, to be published in Physical Review D
null
10.1103/PhysRevD.79.083509
null
hep-ph astro-ph.CO astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supernatural inflation is an attractive model based just on a flat direction with soft SUSY breaking mass terms in the framework of supersymmetry. The beauty of the model is inferred from its name that the model needs no fine-tuning. However, the prediction of the spectral index is $n_s \gae 1$, in contrast to experimental data. In this paper, we show that the beauty of supernatural inflation with the spectral index reduced to $n_s=0.96$ without any fine-tuning, by considering the general feature that a flat direction is lifted by a non-renormalizable term with an A-term.
[ { "created": "Wed, 21 Jan 2009 14:32:13 GMT", "version": "v1" }, { "created": "Mon, 30 Mar 2009 08:01:32 GMT", "version": "v2" } ]
2013-05-29
[ [ "Lin", "Chia-Min", "" ], [ "Cheung", "Kingman", "" ] ]
Supernatural inflation is an attractive model based just on a flat direction with soft SUSY breaking mass terms in the framework of supersymmetry. The beauty of the model is inferred from its name that the model needs no fine-tuning. However, the prediction of the spectral index is $n_s \gae 1$, in contrast to experimental data. In this paper, we show that the beauty of supernatural inflation with the spectral index reduced to $n_s=0.96$ without any fine-tuning, by considering the general feature that a flat direction is lifted by a non-renormalizable term with an A-term.
hep-ph/0303215
Marc Sher
David L. Anderson, Christopher D. Carone and Marc Sher (William and Mary)
Probing the Light Pseudoscalar Window
22 pages, 4 figures
Phys.Rev.D67:115013,2003
10.1103/PhysRevD.67.115013
WM-03-102
hep-ph
null
Very light pseudoscalars can arise from the symmetry-breaking sector in many extensions of the Standard Model. If their mass is below 200 MeV, they can be long-lived and have interesting phenomenology. We discuss the experimental constraints on several models with light pseudoscalars, including one in which the pseudoscalar is naturally fermiophobic. Taking into account the stringent bounds from rare K and B decays, we find allowed parameter space in each model that may be accessible in direct production experiments. In particular, we study the photoproduction of light pseudoscalars at Jefferson Lab and conclude that a beam dump experiment could explore some of the allowed parameter space of these models.
[ { "created": "Tue, 25 Mar 2003 18:39:16 GMT", "version": "v1" } ]
2011-07-19
[ [ "Anderson", "David L.", "", "William and\n Mary" ], [ "Carone", "Christopher D.", "", "William and\n Mary" ], [ "Sher", "Marc", "", "William and\n Mary" ] ]
Very light pseudoscalars can arise from the symmetry-breaking sector in many extensions of the Standard Model. If their mass is below 200 MeV, they can be long-lived and have interesting phenomenology. We discuss the experimental constraints on several models with light pseudoscalars, including one in which the pseudoscalar is naturally fermiophobic. Taking into account the stringent bounds from rare K and B decays, we find allowed parameter space in each model that may be accessible in direct production experiments. In particular, we study the photoproduction of light pseudoscalars at Jefferson Lab and conclude that a beam dump experiment could explore some of the allowed parameter space of these models.
1204.5250
Xin-Qiang Li
Xin-Qiang Li, Yan-Min Li, Gong-Ru Lu and Fang Su
$B_s^0-\bar B_s^0$ mixing in a family non-universal $Z^{\prime}$ model revisited
30 pages, 6 figures, 1 table, pdflatex; accepted by JHEP
null
10.1007/JHEP05(2012)049
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the very recent measurements performed at the LHCb and the Tevatron of the $B_s^0-\bar B_s^0$ mixing, in this paper we revisit it in a family non-universal $Z^{\prime}$ model, to check if a simultaneous explanation for all the mixing observables, especially for the like-sign dimuon charge asymmetry observed by the D0 collaboration, could be made in such a specific model. In the first scenario where the $Z^\prime$ boson contributes only to the off-diagonal element $M_{12}^s$, it is found that, once the combined constraints from $\Delta M_s$, $\phi_s$ and $\Delta \Gamma_s$ are imposed, the model could not explain the measured flavour-specific CP asymmetry $a_{fs}^s$, at least within its $1\sigma$ ranges. In the second scenario where the NP contributes also to the absorptive part $\Gamma_{12}^s$ via tree-level $Z^\prime$-induced $b\to c\bar{c}s$ operators, we find that, with the constraints from $\Delta M_s$, $\phi_s$ and the indirect CP asymmetry in $\bar{B}_d\to J/\psi K_S$ taken into account, the present measured $1\sigma$ experimental ranges for $a_{fs}^s$ could not be reproduced too. Thus, such a specific $Z^\prime$ model with our specific assumptions could not simultaneously reconcile all the present data on $B_s^0-\bar B_s^0$ mixing. Future improved measurements from the LHCb and the proposed superB experiments, especially of the flavour-specific CP asymmetries, are expected to shed light on the issue.
[ { "created": "Tue, 24 Apr 2012 01:40:22 GMT", "version": "v1" } ]
2015-06-04
[ [ "Li", "Xin-Qiang", "" ], [ "Li", "Yan-Min", "" ], [ "Lu", "Gong-Ru", "" ], [ "Su", "Fang", "" ] ]
Motivated by the very recent measurements performed at the LHCb and the Tevatron of the $B_s^0-\bar B_s^0$ mixing, in this paper we revisit it in a family non-universal $Z^{\prime}$ model, to check if a simultaneous explanation for all the mixing observables, especially for the like-sign dimuon charge asymmetry observed by the D0 collaboration, could be made in such a specific model. In the first scenario where the $Z^\prime$ boson contributes only to the off-diagonal element $M_{12}^s$, it is found that, once the combined constraints from $\Delta M_s$, $\phi_s$ and $\Delta \Gamma_s$ are imposed, the model could not explain the measured flavour-specific CP asymmetry $a_{fs}^s$, at least within its $1\sigma$ ranges. In the second scenario where the NP contributes also to the absorptive part $\Gamma_{12}^s$ via tree-level $Z^\prime$-induced $b\to c\bar{c}s$ operators, we find that, with the constraints from $\Delta M_s$, $\phi_s$ and the indirect CP asymmetry in $\bar{B}_d\to J/\psi K_S$ taken into account, the present measured $1\sigma$ experimental ranges for $a_{fs}^s$ could not be reproduced too. Thus, such a specific $Z^\prime$ model with our specific assumptions could not simultaneously reconcile all the present data on $B_s^0-\bar B_s^0$ mixing. Future improved measurements from the LHCb and the proposed superB experiments, especially of the flavour-specific CP asymmetries, are expected to shed light on the issue.
hep-ph/9404359
Alan Stange
D. Dicus, A. Stange and S. Willenbrock
Higgs Decay to Top Quarks at Hadron Colliders
CPP-94-18, BNL-60339, ILL-(TH)-94-9
Phys.Lett. B333 (1994) 126-131
10.1016/0370-2693(94)91017-0
null
hep-ph
null
Higgs bosons which decay principally to top quarks, such as in the minimal supersymmetric model, produce a peak-dip structure in the $gg\to t\bar t$ invariant-mass spectrum. This structure is potentially observable at the CERN Large Hadron Collider. (see BNL theory home page http://penguin.phy.bnl.gov/bnl.html for recent preprints)
[ { "created": "Sun, 1 May 1994 22:00:37 GMT", "version": "v1" } ]
2009-10-28
[ [ "Dicus", "D.", "" ], [ "Stange", "A.", "" ], [ "Willenbrock", "S.", "" ] ]
Higgs bosons which decay principally to top quarks, such as in the minimal supersymmetric model, produce a peak-dip structure in the $gg\to t\bar t$ invariant-mass spectrum. This structure is potentially observable at the CERN Large Hadron Collider. (see BNL theory home page http://penguin.phy.bnl.gov/bnl.html for recent preprints)
0910.2267
Giulia Pancheri Dr.
A. Grau (Granada U.), R.M. Godbole (Bangalore, Indian Inst. Sci.), G. Pancheri (INFN Frascati) and Y.N. Srivastava (INFN & U. Perugia)
Infrared gluons, intrinsic transverse momentum and rising total cross-sections
8 pages, 6 figures, Presented at Hadron Structure '09, Tatranska Strba, September 2009, Slovacchia, to be published in the Conference Proceedings
Nucl.Phys.Proc.Suppl.198:17-24,2010
10.1016/j.nuclphysbps.2009.12.004
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the infrared limit for soft gluon kt-resummation and relate it to physical observables such as the intrinsic transverse momentum and the high energy limit of total cross-sections.
[ { "created": "Mon, 12 Oct 2009 23:30:00 GMT", "version": "v1" } ]
2010-04-22
[ [ "Grau", "A.", "", "Granada U." ], [ "Godbole", "R. M.", "", "Bangalore, Indian Inst. Sci." ], [ "Pancheri", "G.", "", "INFN Frascati" ], [ "Srivastava", "Y. N.", "", "INFN & U. Perugia" ] ]
We discuss the infrared limit for soft gluon kt-resummation and relate it to physical observables such as the intrinsic transverse momentum and the high energy limit of total cross-sections.
2309.08258
Alfiia Mukhaeva
Alexander Bednyakov, Alfiia Mukhaeva
Perturbative Asymptotic Safety and Its Phenomenological Applications
28 pages, 8 figures, review article, published version
Symmetry 2023, 15(8), 1497
10.3390/sym15081497
null
hep-ph hep-th
http://creativecommons.org/licenses/by/4.0/
Asymptotic safety is a remarkable example when fruitful ideas borrowed from statistical physics proliferate to high-energy physics. The concept of asymptotic safety is tightly connected to fixed points (FPs) of the renormalization-group (RG) flow, and generalize well-known asymptotic freedom to a scale-invariant ultraviolet completion with non-vanishing interactions. In this review, we discuss the key ideas behind asymptotic safety, a mechanism for achieving it, and the conditions it imposes on general gauge-Yukawa field theories. We also pay special attention to possible phenomenological applications and provide an overview of standard model (SM) extensions potentially exhibiting asymptotic safety.
[ { "created": "Fri, 15 Sep 2023 09:10:39 GMT", "version": "v1" } ]
2023-09-18
[ [ "Bednyakov", "Alexander", "" ], [ "Mukhaeva", "Alfiia", "" ] ]
Asymptotic safety is a remarkable example when fruitful ideas borrowed from statistical physics proliferate to high-energy physics. The concept of asymptotic safety is tightly connected to fixed points (FPs) of the renormalization-group (RG) flow, and generalize well-known asymptotic freedom to a scale-invariant ultraviolet completion with non-vanishing interactions. In this review, we discuss the key ideas behind asymptotic safety, a mechanism for achieving it, and the conditions it imposes on general gauge-Yukawa field theories. We also pay special attention to possible phenomenological applications and provide an overview of standard model (SM) extensions potentially exhibiting asymptotic safety.
hep-ph/9507460
Robert Fleischer
Andrzej J. Buras and Robert Fleischer
A Determination of the CKM-angle $\alpha$ using Mixing-induced CP Violation in the Decays $B_d\to\pi^+\pi^-$ and $B_d\to K^0 \bar K^0$
12 pages, LaTeX, Figure not included
Phys.Lett.B360:138-142,1995
10.1016/0370-2693(95)01121-6
MPI-PhT/95-72, TUM-T31-96/95, TTP95-30
hep-ph
null
We present a method of determining the CKM-angle $\alpha$ by performing simultaneous measurements of the mixing-induced CP asymmetries of the decays $B_d\to\pi^+\pi^-$ and $B_d\to K^0\bar K^0$. The accuracy of our approach is limited by $SU(3)$-breaking effects originating from $\bar b\to \bar ds\bar s$ QCD-penguin diagrams. Using plausible power-counting arguments we show that these uncertainties are expected to be of the same order as those arising through electroweak penguins in the standard Gronau-London-method in which $\alpha$ is extracted by means of isospin relations among $B\to\pi\pi$ decay amplitudes. Therefore our approach, which does not involve the experimentally difficult mode $B_d\to\pi^0\pi^0$ and is essentially unaffected by electroweak penguins, may be an interesting alternative to determine $\alpha$.
[ { "created": "Mon, 31 Jul 1995 17:19:12 GMT", "version": "v1" } ]
2011-01-27
[ [ "Buras", "Andrzej J.", "" ], [ "Fleischer", "Robert", "" ] ]
We present a method of determining the CKM-angle $\alpha$ by performing simultaneous measurements of the mixing-induced CP asymmetries of the decays $B_d\to\pi^+\pi^-$ and $B_d\to K^0\bar K^0$. The accuracy of our approach is limited by $SU(3)$-breaking effects originating from $\bar b\to \bar ds\bar s$ QCD-penguin diagrams. Using plausible power-counting arguments we show that these uncertainties are expected to be of the same order as those arising through electroweak penguins in the standard Gronau-London-method in which $\alpha$ is extracted by means of isospin relations among $B\to\pi\pi$ decay amplitudes. Therefore our approach, which does not involve the experimentally difficult mode $B_d\to\pi^0\pi^0$ and is essentially unaffected by electroweak penguins, may be an interesting alternative to determine $\alpha$.
hep-ph/0603162
Sascha Bornhauser
Sascha Bornhauser and Manuel Drees
The Passage of Ultrarelativistic Neutralinos through Matter
28 pages, 11 figures
Astropart.Phys.27:30-45,2007
10.1016/j.astropartphys.2006.09.002
null
hep-ph
null
The origin of the most energetic cosmic ray events, with $E \gsim 10^{20}$ eV, remains mysterious. One possibility is that they are produced in the decay of very massive, long--lived particles. It has been suggested that these so--called ``top--down scenarios'' can be tested by searching for ultrarelativistic neutralinos, which would be produced copiously if superparticles exist at or near the TeV scale. In this paper we present a detailed analysis of the interactions of such neutralinos with ordinary matter. To this end we compute several new contributions to the total interaction cross section; in particular, the case of higgsino--like neutralinos is treated for the first time. We also carefully solve the transport equations. We show that a semi--analytical solution that has been used in the literature to treat the somewhat analogous propagation of $\tau$ neutrinos leads to large errors; we therefore use a straightforward numerical method to solve these integro--differential equations.
[ { "created": "Tue, 21 Mar 2006 15:53:48 GMT", "version": "v1" } ]
2011-05-23
[ [ "Bornhauser", "Sascha", "" ], [ "Drees", "Manuel", "" ] ]
The origin of the most energetic cosmic ray events, with $E \gsim 10^{20}$ eV, remains mysterious. One possibility is that they are produced in the decay of very massive, long--lived particles. It has been suggested that these so--called ``top--down scenarios'' can be tested by searching for ultrarelativistic neutralinos, which would be produced copiously if superparticles exist at or near the TeV scale. In this paper we present a detailed analysis of the interactions of such neutralinos with ordinary matter. To this end we compute several new contributions to the total interaction cross section; in particular, the case of higgsino--like neutralinos is treated for the first time. We also carefully solve the transport equations. We show that a semi--analytical solution that has been used in the literature to treat the somewhat analogous propagation of $\tau$ neutrinos leads to large errors; we therefore use a straightforward numerical method to solve these integro--differential equations.
hep-ph/9404252
Ed Stoeffhaas
F. Halzen and J.E Jacobsen
The Indirect Detection of Halo Dark Matter
Talk given by F. Halzen at the International Conference on Critique of the Sources of Dark Matter in the Universe, UCLA, 1994. Standard Latex, 15 pages. Seven uufiled EPS figures included
null
null
MAD/PH/823
hep-ph astro-ph
null
High energy particles are produced by the annihilation of dark matter particles in our galaxy. These are presently searched for using balloon-borne antiproton and positron detectors and large area, deep underground neutrino telescopes. Dark matter particles, trapped inside the sun, are an abundant source of such neutrinos. From both the cosmological and particle physics points of view the lightest, stable supersymmetric particle or neutralino is arguably the leading dark matter candidate. Its mass is bracketed by a minimum value of order a few tens of GeV, determined from unsuccessful accelerator searches, and a maximum value of order 1~TeV imposed by particle physics as well as cosmological constraints. Back-of-the-envelope calculations are sufficient to demonstrate how present neutrino telescopes are competitive with existing and future particle colliders such as the LHC in the search for supersymmetry. We emphasize that a $1\,\rm km^2$ area is the natural scale for a future instrument capable of probing the full GeV--TeV neutralino mass range by searching for high energy neutrinos produced by their annihilation in the sun.
[ { "created": "Mon, 11 Apr 1994 19:05:44 GMT", "version": "v1" } ]
2016-09-01
[ [ "Halzen", "F.", "" ], [ "Jacobsen", "J. E", "" ] ]
High energy particles are produced by the annihilation of dark matter particles in our galaxy. These are presently searched for using balloon-borne antiproton and positron detectors and large area, deep underground neutrino telescopes. Dark matter particles, trapped inside the sun, are an abundant source of such neutrinos. From both the cosmological and particle physics points of view the lightest, stable supersymmetric particle or neutralino is arguably the leading dark matter candidate. Its mass is bracketed by a minimum value of order a few tens of GeV, determined from unsuccessful accelerator searches, and a maximum value of order 1~TeV imposed by particle physics as well as cosmological constraints. Back-of-the-envelope calculations are sufficient to demonstrate how present neutrino telescopes are competitive with existing and future particle colliders such as the LHC in the search for supersymmetry. We emphasize that a $1\,\rm km^2$ area is the natural scale for a future instrument capable of probing the full GeV--TeV neutralino mass range by searching for high energy neutrinos produced by their annihilation in the sun.
hep-ph/0301100
Arttu Rajantie
A. Rajantie
Formation of Magnetic Monopoles in Hot Gauge Theories
5 pages, talk given at Strong and Electroweak Matter 2002, Heidelberg, October 2-5, 2002
null
10.1142/9789812704498_0068
DAMTP-2003-2
hep-ph
null
In this talk, I discuss the formation of magnetic monopoles in a phase transition from the confining SU(2) phase to the Coulomb phase in a hot Georgi-Glashow model. I argue that monopoles are formed from long-wavelength thermal fluctuations, which freeze out after the phase transition.
[ { "created": "Wed, 15 Jan 2003 10:04:13 GMT", "version": "v1" } ]
2017-08-23
[ [ "Rajantie", "A.", "" ] ]
In this talk, I discuss the formation of magnetic monopoles in a phase transition from the confining SU(2) phase to the Coulomb phase in a hot Georgi-Glashow model. I argue that monopoles are formed from long-wavelength thermal fluctuations, which freeze out after the phase transition.
1705.09978
J. Lorenzo Diaz-Cruz
J. Lorenzo Diaz-Cruz
Where have all the large Representations gone?
7 pages, 2 tables
null
null
CIFFU-03-17
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Gauge theories describe the interactions of the fundamental building blocks of nature with great success. The Standard Model achieves a partial unification of the electromagnetic and weak interactions, and it also acomodates the strong interactions. The known quarks and leptons appear in the fundamental representations (or singlets) of the SU(3)_cxSU(2)_L x U(1)_Y gauge symmetry. However, larger representations (EW triplets, color sextes, etc.) could also occur in principle. Bounds on such exotic states based on electroweak precision tests, unitarity, perturbativity and collider searches, indicate that they should be very heavy or may be non-existent. But why only small representations occur in nature? Several ideas that could give some light into this problem are discussed here, including the approach of Nielsen et al, as well as the possible compositeness of quarks and leptons. Then, we discuss the problem within the context of grand unified theories, where a principle of "minimal complexity" is proposed to restrict the size of large representations, when they are required to form unified multiplets.
[ { "created": "Sun, 28 May 2017 19:13:49 GMT", "version": "v1" } ]
2017-05-30
[ [ "Diaz-Cruz", "J. Lorenzo", "" ] ]
Gauge theories describe the interactions of the fundamental building blocks of nature with great success. The Standard Model achieves a partial unification of the electromagnetic and weak interactions, and it also acomodates the strong interactions. The known quarks and leptons appear in the fundamental representations (or singlets) of the SU(3)_cxSU(2)_L x U(1)_Y gauge symmetry. However, larger representations (EW triplets, color sextes, etc.) could also occur in principle. Bounds on such exotic states based on electroweak precision tests, unitarity, perturbativity and collider searches, indicate that they should be very heavy or may be non-existent. But why only small representations occur in nature? Several ideas that could give some light into this problem are discussed here, including the approach of Nielsen et al, as well as the possible compositeness of quarks and leptons. Then, we discuss the problem within the context of grand unified theories, where a principle of "minimal complexity" is proposed to restrict the size of large representations, when they are required to form unified multiplets.
0905.4865
Alessandro Mirizzi
Alessandro Mirizzi (Max Planck Inst., Munich), Javier Redondo (Deutsches Elektronen Synchrotron, Hamburg), Guenter Sigl (Hamburg University)
Constraining resonant photon-axion conversions in the Early Universe
Revised version (19 pages, 3 eps figures). Matches the one published on JCAP. Discussion enlarged in the conclusions
JCAP08 (2009) 001
10.1088/1475-7516/2009/08/001
DESY-09-071, MPP-2009-58
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The presence of a primordial magnetic field would have induced resonant conversions between photons and axion-like particles (ALPs) during the thermal history of the Universe. These conversions would have distorted the blackbody spectrum of the cosmic microwave background (CMB). In this context, we derive bounds on the photon-ALP resonant conversions using the high precision CMB spectral data collected by the FIRAS instrument on board of the Cosmic Background Explorer. We obtain upper limits on the product of the photon-ALP coupling constant g times the magnetic field strength B down to g B > 10^{-13} GeV^{-1} nG for ALP masses below the eV scale.
[ { "created": "Fri, 29 May 2009 16:29:53 GMT", "version": "v1" }, { "created": "Thu, 6 Aug 2009 15:22:27 GMT", "version": "v2" } ]
2015-05-13
[ [ "Mirizzi", "Alessandro", "", "Max Planck Inst., Munich" ], [ "Redondo", "Javier", "", "Deutsches Elektronen Synchrotron, Hamburg" ], [ "Sigl", "Guenter", "", "Hamburg\n University" ] ]
The presence of a primordial magnetic field would have induced resonant conversions between photons and axion-like particles (ALPs) during the thermal history of the Universe. These conversions would have distorted the blackbody spectrum of the cosmic microwave background (CMB). In this context, we derive bounds on the photon-ALP resonant conversions using the high precision CMB spectral data collected by the FIRAS instrument on board of the Cosmic Background Explorer. We obtain upper limits on the product of the photon-ALP coupling constant g times the magnetic field strength B down to g B > 10^{-13} GeV^{-1} nG for ALP masses below the eV scale.
1910.04409
Mohammad Alhakami
Mohammad H. Alhakami
Spectroscopy of excited charmed mesons
null
Phys. Rev. D 101, 016001 (2020)
10.1103/PhysRevD.101.016001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive mass formulas for the $P$-wave orbitally excited $D^*_{0(s)}$, $D^\prime_{1(s)}$, $D_{1(s)}$, and $D^*_{2(s)}$ heavy charmed mesons including all effects from one-loop corrections that contribute at leading order in chiral expansion. In our formalism, the effects to first order in $m_q$, where $m_q$ is the light quark mass, and to first order in $m^{-1}_c$, where $m_c$ is the charm quark mass, and $m_q/m_c$ terms are considered. The experimental and lattice QCD results on the charmed meson spectra are employed to fix the large number of counterterms appearing in the effective chiral Lagrangian used in this work. This allows us to test the validity of perturbative expansion of our theory. The results presented in the current paper are useful to other applications of excited charmed and bottom meson systems.
[ { "created": "Thu, 10 Oct 2019 07:42:40 GMT", "version": "v1" }, { "created": "Thu, 2 Jan 2020 22:10:32 GMT", "version": "v2" } ]
2020-01-06
[ [ "Alhakami", "Mohammad H.", "" ] ]
We derive mass formulas for the $P$-wave orbitally excited $D^*_{0(s)}$, $D^\prime_{1(s)}$, $D_{1(s)}$, and $D^*_{2(s)}$ heavy charmed mesons including all effects from one-loop corrections that contribute at leading order in chiral expansion. In our formalism, the effects to first order in $m_q$, where $m_q$ is the light quark mass, and to first order in $m^{-1}_c$, where $m_c$ is the charm quark mass, and $m_q/m_c$ terms are considered. The experimental and lattice QCD results on the charmed meson spectra are employed to fix the large number of counterterms appearing in the effective chiral Lagrangian used in this work. This allows us to test the validity of perturbative expansion of our theory. The results presented in the current paper are useful to other applications of excited charmed and bottom meson systems.
1110.0874
Michael Andreas Schmidt
Michael A. Schmidt and Alexei Yu. Smirnov
Neutrino Masses and a Fourth Generation of Fermions
33 pages, 4 figures; Eq. (18) corrected and thus corrections to Eqs. (21,26-28,41,42,44-46) and figures, the loop contribution reduced by 2 orders of magnitude; general conclusions unchanged; accepted by Nucl. Phys. B
null
10.1016/j.nuclphysb.2011.11.023
IPPP/11/51; DCPT/11/102
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study neutrino mass generation in models with four chiral families of leptons and quarks and four right handed neutrinos. Generically, in these models there are three different contributions to the light neutrino masses: the usual see-saw contribution, the tree-level contribution due to mixing of light neutrinos with neutrino of the fourth generation, and the two loop contribution due to the Majorana mass term of the fourth neutrino. We study properties of these contributions and their experimental bounds. The regions of the parameters (mixings of the fourth neutrino, masses of RH neutrino components, etc.) have been identified where various contributions dominate. New possibilities of a realization of the flavour symmetries in the four family context are explored. In particular, we consider applications of the smallest groups, e.g. SG(20,3), with irreducible representation 4.
[ { "created": "Wed, 5 Oct 2011 00:33:05 GMT", "version": "v1" }, { "created": "Thu, 13 Oct 2011 23:55:52 GMT", "version": "v2" }, { "created": "Mon, 12 Dec 2011 19:46:25 GMT", "version": "v3" } ]
2015-05-30
[ [ "Schmidt", "Michael A.", "" ], [ "Smirnov", "Alexei Yu.", "" ] ]
We study neutrino mass generation in models with four chiral families of leptons and quarks and four right handed neutrinos. Generically, in these models there are three different contributions to the light neutrino masses: the usual see-saw contribution, the tree-level contribution due to mixing of light neutrinos with neutrino of the fourth generation, and the two loop contribution due to the Majorana mass term of the fourth neutrino. We study properties of these contributions and their experimental bounds. The regions of the parameters (mixings of the fourth neutrino, masses of RH neutrino components, etc.) have been identified where various contributions dominate. New possibilities of a realization of the flavour symmetries in the four family context are explored. In particular, we consider applications of the smallest groups, e.g. SG(20,3), with irreducible representation 4.
1710.08193
Maciej Rybczynski
P. Kankiewicz, M. Rybczynski, Z. Wlodarczyk, G. Wilk
Muon bundles from the Universe
4 pages, Proceedings for 17th International Conference on Strangeness in Quark Matter, Utrecht, the Netherlands
null
10.1051/epjconf/201817120003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently the CERN ALICE experiment, in its dedicated cosmic ray run, observed muon bundles of very high multiplicities, thereby confirming similar findings from the LEP era at CERN (in the CosmoLEP project). Significant evidence for anisotropy of arrival directions of the observed high multiplicity muonic bundles is found. Estimated directionality suggests their possible extragalactic provenance. We argue that muonic bundles of highest multiplicity are produced by strangelets, hypothetical stable lumps of strange quark matter infiltrating our Universe.
[ { "created": "Mon, 23 Oct 2017 10:48:35 GMT", "version": "v1" } ]
2018-03-14
[ [ "Kankiewicz", "P.", "" ], [ "Rybczynski", "M.", "" ], [ "Wlodarczyk", "Z.", "" ], [ "Wilk", "G.", "" ] ]
Recently the CERN ALICE experiment, in its dedicated cosmic ray run, observed muon bundles of very high multiplicities, thereby confirming similar findings from the LEP era at CERN (in the CosmoLEP project). Significant evidence for anisotropy of arrival directions of the observed high multiplicity muonic bundles is found. Estimated directionality suggests their possible extragalactic provenance. We argue that muonic bundles of highest multiplicity are produced by strangelets, hypothetical stable lumps of strange quark matter infiltrating our Universe.
hep-ph/0011307
Alessandro Strumia
Riccardo Barbieri and Alessandro Strumia
Non standard analysis of the solar neutrino anomaly (updated including the SNO day/night spectral data)
Version 5: addendum about the SNO NC data at pages 10, 11
JHEP 0012:016,2000
10.1088/1126-6708/2000/12/016
IFUP-TH/2000-43, CERN-TH/2000-345 and SNS-PH/00-17
hep-ph hep-ex
null
Continuing previous work, a model independent analysis of the solar neutrino anomaly is performed in terms of neutrino oscillations, allowing a comparison with the predictions of the Standard Solar Model. SMA and LMA solutions emerge also in this case, although somewhat different from the standard ones. The significance of the NC/CC double ratio measurable in SNO is illustrated in this context.
[ { "created": "Fri, 24 Nov 2000 18:28:47 GMT", "version": "v1" }, { "created": "Sat, 25 Nov 2000 12:17:29 GMT", "version": "v2" }, { "created": "Fri, 12 Jan 2001 17:38:36 GMT", "version": "v3" }, { "created": "Fri, 27 Jul 2001 17:23:02 GMT", "version": "v4" }, { "created": "Wed, 10 Jul 2002 17:50:01 GMT", "version": "v5" } ]
2009-10-31
[ [ "Barbieri", "Riccardo", "" ], [ "Strumia", "Alessandro", "" ] ]
Continuing previous work, a model independent analysis of the solar neutrino anomaly is performed in terms of neutrino oscillations, allowing a comparison with the predictions of the Standard Solar Model. SMA and LMA solutions emerge also in this case, although somewhat different from the standard ones. The significance of the NC/CC double ratio measurable in SNO is illustrated in this context.
1202.0845
Igor Strakovsky
Ron L. Workman, Mark W. Paris, William J. Briscoe, Igor I. Strakovsky (GWU)
Unified Chew-Mandelstam SAID analysis of pion photoproduction data
11 pages, 9 figures, and 2 tables
null
10.1103/PhysRevC.86.015202
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A unified description of single-pion photoproduction data, together with pion- and eta-hadroproduction data, has been achieved in a Chew-Mandelstam parametrization which is consistent with unitarity at the two-body level. Energy-dependent and single-energy partial wave analyses of pion photoproduction data have been performed and compared to previous SAID fits and multipoles from the Mainz and Bonn-Gatchina groups.
[ { "created": "Sat, 4 Feb 2012 00:00:34 GMT", "version": "v1" } ]
2013-05-30
[ [ "Workman", "Ron L.", "", "GWU" ], [ "Paris", "Mark W.", "", "GWU" ], [ "Briscoe", "William J.", "", "GWU" ], [ "Strakovsky", "Igor I.", "", "GWU" ] ]
A unified description of single-pion photoproduction data, together with pion- and eta-hadroproduction data, has been achieved in a Chew-Mandelstam parametrization which is consistent with unitarity at the two-body level. Energy-dependent and single-energy partial wave analyses of pion photoproduction data have been performed and compared to previous SAID fits and multipoles from the Mainz and Bonn-Gatchina groups.
1612.08576
Luxmi Machahari
Luxmi Machahari, D. K. Choudhury and P.K.Sahariah
A study of structure functions with the DGLAP: equations at small $x$ with $O(x)$ and $O(x ^2 )$
The paper is of 18 pages and 4 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We obtain a pair of second order differential equations in two variables $x$ and $t$ from the coupled DGLAP QCD evolution equations at small $x$ using the standard Taylor series expansion method.To that end we keep terms upto $O(x^2 )$.We use the standard assumption about the relationship between the singlet Structure Function and the gluon distributions available in current literature. We solve the taylor approximated $O(x)$ DGLAP equations by Lagrange's auxiliary method and $O(x^2)$ equation by Method of Separation of Variables and then show that the two solutions obtained in each for $O(x)$ and $O(x^2)$ are not identical in general.Analysis of the results obtained are done in the range of the recent HERA data.
[ { "created": "Tue, 27 Dec 2016 11:18:08 GMT", "version": "v1" } ]
2016-12-28
[ [ "Machahari", "Luxmi", "" ], [ "Choudhury", "D. K.", "" ], [ "Sahariah", "P. K.", "" ] ]
We obtain a pair of second order differential equations in two variables $x$ and $t$ from the coupled DGLAP QCD evolution equations at small $x$ using the standard Taylor series expansion method.To that end we keep terms upto $O(x^2 )$.We use the standard assumption about the relationship between the singlet Structure Function and the gluon distributions available in current literature. We solve the taylor approximated $O(x)$ DGLAP equations by Lagrange's auxiliary method and $O(x^2)$ equation by Method of Separation of Variables and then show that the two solutions obtained in each for $O(x)$ and $O(x^2)$ are not identical in general.Analysis of the results obtained are done in the range of the recent HERA data.
hep-ph/9406428
Zhora Jikia
George Jikia and Avto Tkabladze
QCD Corrections to $b\bar b/c\bar c$ Pair Production in Polarized $\gamma\gamma$ Collisions and the Intermediate Mass Higgs Signal
(Talk given at the Workshop on gamma--gamma colliders, March 28-31, 1994, Lawrence Berkeley Laboratory), LaTeX, 5 pages, 3 figures (compressed + uuencoded PS file)
Nucl.Instrum.Meth.A355:81-83,1995
10.1016/0168-9002(94)01181-8
null
hep-ph
null
We present production rates of the two- and three-jet final states for the processes of massive $c\bar c/b\bar b$ quark production in circularly polarized photon-photon collisions, including QCD radiative corrections. Lowest order cross section, one-loop virtual correction and gluon emission correction are shown to be of the same order of magnitude for $b\bar b$ quark production at $\sqrt{s_{\gamma\gamma}}\sim 100$~GeV. It is shown that the signal from intermediate mass Higgs boson is observable at photon-photon collider, although the statistical significance is substantially reduced with respect to the tree level calculation.
[ { "created": "Thu, 30 Jun 1994 22:01:50 GMT", "version": "v1" } ]
2011-01-25
[ [ "Jikia", "George", "" ], [ "Tkabladze", "Avto", "" ] ]
We present production rates of the two- and three-jet final states for the processes of massive $c\bar c/b\bar b$ quark production in circularly polarized photon-photon collisions, including QCD radiative corrections. Lowest order cross section, one-loop virtual correction and gluon emission correction are shown to be of the same order of magnitude for $b\bar b$ quark production at $\sqrt{s_{\gamma\gamma}}\sim 100$~GeV. It is shown that the signal from intermediate mass Higgs boson is observable at photon-photon collider, although the statistical significance is substantially reduced with respect to the tree level calculation.
hep-ph/0508185
Konstantin Matchev
Andreas Birkedal, Konstantin T. Matchev, Maxim Perelstein
Phenomenology of Higgsless Models at the LHC and the ILC
6 pages, 6 figures, to appear in the proceedings of the 2005 International Linear Collider Workshop, Stanford, USA
ECONF C050318:0314,2005
null
UFIFT-HEP-05-21
hep-ph
null
We investigate the signatures of the recently proposed Higgsless models at future colliders. We focus on tests of the mechanism of partial unitarity restoration in the longitudinal vector boson scattering, which do not depend on any Higgsless model-building details. We study the LHC discovery reach for charged massive vector boson resonances and show that all of the preferred parameter space will be probed with $100 {\rm fb}^{-1}$ of LHC data. We also discuss the prospects for experimental verification of the Higgsless nature of the model at the LHC. In addition, in this talk we present new results relevant for the discovery potential of Higgsless models at the International Linear Collider (ILC).
[ { "created": "Wed, 17 Aug 2005 01:59:37 GMT", "version": "v1" } ]
2009-10-09
[ [ "Birkedal", "Andreas", "" ], [ "Matchev", "Konstantin T.", "" ], [ "Perelstein", "Maxim", "" ] ]
We investigate the signatures of the recently proposed Higgsless models at future colliders. We focus on tests of the mechanism of partial unitarity restoration in the longitudinal vector boson scattering, which do not depend on any Higgsless model-building details. We study the LHC discovery reach for charged massive vector boson resonances and show that all of the preferred parameter space will be probed with $100 {\rm fb}^{-1}$ of LHC data. We also discuss the prospects for experimental verification of the Higgsless nature of the model at the LHC. In addition, in this talk we present new results relevant for the discovery potential of Higgsless models at the International Linear Collider (ILC).
0711.0148
Johan Bijnens
Johan Bijnens and Karim Ghorbani (Lund)
Isospin breaking in $K\pi$ vector form-factors for the weak and rare decays $K_{\ell3}$, $K\to\pi\nu\bar\nu$ and $K\to\pi\ell^+\ell^-$
31 pages
null
null
LU TP 07-29
hep-ph
null
We calculate the two form-factors for the four Kaon to pion transitions via a vector current to order $p^6$ in Chiral Perturbation Theory to first order in isospin breaking via the quark masses. In addition we derive relations between these form-factors valid to first order in the up-down quark-mass difference but to all orders in Chiral Perturbation Theory. We present numerical results for all eight form-factors at $t=0$ and for varying $t$ and for the scalar form-factors at the Callan-Treiman point.
[ { "created": "Thu, 1 Nov 2007 16:09:30 GMT", "version": "v1" } ]
2007-11-02
[ [ "Bijnens", "Johan", "", "Lund" ], [ "Ghorbani", "Karim", "", "Lund" ] ]
We calculate the two form-factors for the four Kaon to pion transitions via a vector current to order $p^6$ in Chiral Perturbation Theory to first order in isospin breaking via the quark masses. In addition we derive relations between these form-factors valid to first order in the up-down quark-mass difference but to all orders in Chiral Perturbation Theory. We present numerical results for all eight form-factors at $t=0$ and for varying $t$ and for the scalar form-factors at the Callan-Treiman point.
hep-ph/0005330
Jonathan Lenaghan
J. T. Lenaghan (Yale University and The Niels Bohr Institute)
Influence of the U(1)_A Anomaly on the QCD Phase Transition
5 pages, 3 figures, Revtex, discussion extended and references added. To appear in PRD
Phys.Rev. D63 (2001) 037901
10.1103/PhysRevD.63.037901
BNL-NT-00/15
hep-ph nucl-th
null
The SU(3)_{r} \times SU(3)_{\ell} linear sigma model is used to study the chiral symmetry restoring phase transition of QCD at nonzero temperature. The line of second order phase transitions separating the first order and smooth crossover regions is located in the plane of the strange and nonstrange quark masses. It is found that if the U(1)_{A} symmetry is explicitly broken by the U(1)_{A} anomaly then there is a smooth crossover to the chirally symmetric phase for physical values of the quark masses. If the U(1)_{A} anomaly is absent, then there is a phase transition provided that the \sigma meson mass is at least 600 MeV. In both cases, the region of first order phase transitions in the quark mass plane is enlarged as the mass of the \sigma meson is increased.
[ { "created": "Wed, 31 May 2000 20:54:49 GMT", "version": "v1" }, { "created": "Fri, 1 Dec 2000 15:37:48 GMT", "version": "v2" } ]
2009-10-31
[ [ "Lenaghan", "J. T.", "", "Yale University and The Niels Bohr Institute" ] ]
The SU(3)_{r} \times SU(3)_{\ell} linear sigma model is used to study the chiral symmetry restoring phase transition of QCD at nonzero temperature. The line of second order phase transitions separating the first order and smooth crossover regions is located in the plane of the strange and nonstrange quark masses. It is found that if the U(1)_{A} symmetry is explicitly broken by the U(1)_{A} anomaly then there is a smooth crossover to the chirally symmetric phase for physical values of the quark masses. If the U(1)_{A} anomaly is absent, then there is a phase transition provided that the \sigma meson mass is at least 600 MeV. In both cases, the region of first order phase transitions in the quark mass plane is enlarged as the mass of the \sigma meson is increased.
hep-ph/9505347
Brahmachari Biswajoy
Biswajoy Brahmachari and Rabindra N Mohapatra
Low $\alpha_{strong}(M_Z)$, Intermediate Scale SUSY SO(10) GUT and Its Implications
Latex file with one figure. Hard copy of the figure is available by Fax from the submitter
Phys.Lett.B357:566-572,1995
10.1016/0370-2693(95)00968-Q
UMD-PP-95-138
hep-ph
null
We show that one of the ways of obtaining consistency between the idea of supersymmetric grand unification and an apparent low value of $\alpha_{strong}(M_Z)\simeq .11$ indicated by several low energy experiments is to have an intermediate scale corresponding to a local $B-L$ symmetry breaking around the mass scale of $10^{10}$ to $10^{12}$ GeV. We discuss the realization of this idea within the framework of supersymmetric $SO(10)$ grand unified theories with spectra of particles derivable from simple superstring-inspired versions of this model. We then study the $b-\tau$ mass unification within this class of models and show that due to the influence of new gauge and Yukawa interactions beyond the intermediate scale, the prediction of the $b$-quark mass comes out well within the presently accepted values. We also discuss an un-orthodox class of SUSY models inspired by some theoretical considerations having two pairs of Higgs doublets at low energy and show that they also can lead to unification with intermediate scales and low $\alpha_{s}(M_Z)$ as desired.
[ { "created": "Sun, 21 May 1995 17:27:59 GMT", "version": "v1" } ]
2009-10-02
[ [ "Brahmachari", "Biswajoy", "" ], [ "Mohapatra", "Rabindra N", "" ] ]
We show that one of the ways of obtaining consistency between the idea of supersymmetric grand unification and an apparent low value of $\alpha_{strong}(M_Z)\simeq .11$ indicated by several low energy experiments is to have an intermediate scale corresponding to a local $B-L$ symmetry breaking around the mass scale of $10^{10}$ to $10^{12}$ GeV. We discuss the realization of this idea within the framework of supersymmetric $SO(10)$ grand unified theories with spectra of particles derivable from simple superstring-inspired versions of this model. We then study the $b-\tau$ mass unification within this class of models and show that due to the influence of new gauge and Yukawa interactions beyond the intermediate scale, the prediction of the $b$-quark mass comes out well within the presently accepted values. We also discuss an un-orthodox class of SUSY models inspired by some theoretical considerations having two pairs of Higgs doublets at low energy and show that they also can lead to unification with intermediate scales and low $\alpha_{s}(M_Z)$ as desired.
2009.08450
Yu Jia
Feng Feng, Yingsheng Huang, Yu Jia, Wen-Long Sang, Xiaonu Xiong, Jia-Yue Zhang
Fragmentation production of fully-charmed tetraquarks at LHC
9 pages, 1 table, 3 figures
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $X(6900)$ resonance, very recently discovered in the double-$J/\psi$ channel at LHCb experiment, has spurred intensive interest in unravelling the nature of the fully charmed tetraquark state. The aim of this paper is to present a model-independent theoretical framework to study the inclusive production of this novel species of exotic hadrons, the resonances composed of four heavy quark (commonly referred to as $T_{4c}$), at large $p_T$ in hadron collision experiments. Appealing to asymptotic freedom and the fact $m_c\gg \Lambda_{\rm QCD}$, we propose that the nonpertubative yet universal gluon-to-$T_{4c}$ fragmentation function, can be decomposed into the product of the perturbatively calculable short-distance coefficient and the long-distance NRQCD matrix elements. We compute the short-distance coefficient at lowest-order in $\alpha_s$ and velocity expansion. Adopting the diquark ansatz to roughly estimate those not-yet-known NRQCD matrix elements, together with the standard QCD factorization theorem, we predict the differential production rates for the $T_{4c/4b}(0^{++})$ and $T_{4c/4b}(2^{++})$ at large $p_T$ in $pp$ collision, which eagerly awaits the confrontation with the future LHC experiments.
[ { "created": "Thu, 17 Sep 2020 17:58:41 GMT", "version": "v1" } ]
2020-09-18
[ [ "Feng", "Feng", "" ], [ "Huang", "Yingsheng", "" ], [ "Jia", "Yu", "" ], [ "Sang", "Wen-Long", "" ], [ "Xiong", "Xiaonu", "" ], [ "Zhang", "Jia-Yue", "" ] ]
The $X(6900)$ resonance, very recently discovered in the double-$J/\psi$ channel at LHCb experiment, has spurred intensive interest in unravelling the nature of the fully charmed tetraquark state. The aim of this paper is to present a model-independent theoretical framework to study the inclusive production of this novel species of exotic hadrons, the resonances composed of four heavy quark (commonly referred to as $T_{4c}$), at large $p_T$ in hadron collision experiments. Appealing to asymptotic freedom and the fact $m_c\gg \Lambda_{\rm QCD}$, we propose that the nonpertubative yet universal gluon-to-$T_{4c}$ fragmentation function, can be decomposed into the product of the perturbatively calculable short-distance coefficient and the long-distance NRQCD matrix elements. We compute the short-distance coefficient at lowest-order in $\alpha_s$ and velocity expansion. Adopting the diquark ansatz to roughly estimate those not-yet-known NRQCD matrix elements, together with the standard QCD factorization theorem, we predict the differential production rates for the $T_{4c/4b}(0^{++})$ and $T_{4c/4b}(2^{++})$ at large $p_T$ in $pp$ collision, which eagerly awaits the confrontation with the future LHC experiments.
2012.03266
Gongjun Choi
Gongjun Choi, Tsutomu T. Yanagida, Norimi Yokozaki
The Upper Bound of the Second Higgs Boson Mass in Minimal Gauge Mediation with the Gravitino Warm Dark Matter
v2: refs added; version published in JHEP
JHEP04(2021)024
10.1007/JHEP04(2021)024
null
hep-ph astro-ph.CO hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A keV-scale gravitino arsing from a minimal supersymmetric (SUSY) Standard Model (MSSM) is an interesting possibility since the small scale problems that $\Lambda$CDM model encounters in the modern cosmology could be alleviated with the keV-scale gravitino serving as the warm dark matter (WDM). Such a light gravitino asks for a low scale supersymmetry (SUSY) breaking for which the gauge mediation (GM) is required as a consistent SUSY-breaking mediation mechanism. In this paper, we show upperbounds of the masses of the second CP-even Higgs boson $H$ and the CP-odd Higgs boson $A$, assuming the keV-scale gravitino to be responsible for the current DM relic abundance: the upperbound on the mass of $H/A$ is found to be $\sim 4$ TeV for the gravitino mass of $\mathcal{O}(10$-$100)$ keV. Interestingly, the mass of $H/A$ can be as small as 2-3 TeV and the predicted $\tan\beta$ is as large as 55-60 for the gravitino mass of $\mathcal{O}(10)$ keV. This will be tested in the near future Large Hadron Collider (LHC) experiments.
[ { "created": "Sun, 6 Dec 2020 13:42:21 GMT", "version": "v1" }, { "created": "Wed, 7 Apr 2021 13:11:21 GMT", "version": "v2" } ]
2021-04-08
[ [ "Choi", "Gongjun", "" ], [ "Yanagida", "Tsutomu T.", "" ], [ "Yokozaki", "Norimi", "" ] ]
A keV-scale gravitino arsing from a minimal supersymmetric (SUSY) Standard Model (MSSM) is an interesting possibility since the small scale problems that $\Lambda$CDM model encounters in the modern cosmology could be alleviated with the keV-scale gravitino serving as the warm dark matter (WDM). Such a light gravitino asks for a low scale supersymmetry (SUSY) breaking for which the gauge mediation (GM) is required as a consistent SUSY-breaking mediation mechanism. In this paper, we show upperbounds of the masses of the second CP-even Higgs boson $H$ and the CP-odd Higgs boson $A$, assuming the keV-scale gravitino to be responsible for the current DM relic abundance: the upperbound on the mass of $H/A$ is found to be $\sim 4$ TeV for the gravitino mass of $\mathcal{O}(10$-$100)$ keV. Interestingly, the mass of $H/A$ can be as small as 2-3 TeV and the predicted $\tan\beta$ is as large as 55-60 for the gravitino mass of $\mathcal{O}(10)$ keV. This will be tested in the near future Large Hadron Collider (LHC) experiments.
2203.17169
Hyeon-Dong Son
Hyeon-Dong Son
Isovector helicity quark quasi-distributions inside a large Nc nucleon
12 pages and 7 figures. Version accepted for publication in Physics Letters B
null
10.1016/j.physletb.2023.137741
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this letter, we report the results for the isovector polarized quark quasi-distribution functions $\Delta u(x,v) - \Delta d(x,v)$ in the large $N_c$, calculated within the chiral quark-soliton model. It is shown that the polarized quark quasi-distributions present good convergence to the light-cone PDFs in the limit of the nucleon boost momentum $P_N \to \infty$ (or the velocity $v \to 1$), compared to the case of the unpolarized isosinglet distributions.
[ { "created": "Thu, 31 Mar 2022 16:44:39 GMT", "version": "v1" }, { "created": "Fri, 3 Feb 2023 01:08:36 GMT", "version": "v2" } ]
2023-02-06
[ [ "Son", "Hyeon-Dong", "" ] ]
In this letter, we report the results for the isovector polarized quark quasi-distribution functions $\Delta u(x,v) - \Delta d(x,v)$ in the large $N_c$, calculated within the chiral quark-soliton model. It is shown that the polarized quark quasi-distributions present good convergence to the light-cone PDFs in the limit of the nucleon boost momentum $P_N \to \infty$ (or the velocity $v \to 1$), compared to the case of the unpolarized isosinglet distributions.
1111.4495
Keith Olive
Bruce A. Campbell, John Ellis, Keith A. Olive
Phenomenology and Cosmology of an Electroweak Pseudo-Dilaton and Electroweak Baryons
34 pages, 4 figures, additional references added
null
10.1007/JHEP03(2012)026
KCL-PH-TH/2011-38; LCTS/2011-20; CERN-PH-TH/2011-283; UMN-TH-3019/11; FTPI-MINN-11/27
hep-ph astro-ph.CO hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In many strongly-interacting models of electroweak symmetry breaking the lowest-lying observable particle is a pseudo-Goldstone boson of approximate scale symmetry, the pseudo-dilaton. Its interactions with Standard Model particles can be described using a low-energy effective nonlinear chiral Lagrangian supplemented by terms that restore approximate scale symmetry, yielding couplings of the pseudo-dilaton that differ from those of a Standard Model Higgs boson by fixed factors. We review the experimental constraints on such a pseudo-dilaton in light of new data from the LHC and elsewhere. The effective nonlinear chiral Lagrangian has Skyrmion solutions that may be identified with the `electroweak baryons' of the underlying strongly-interacting theory, whose nature may be revealed by the properties of the Skyrmions. We discuss the finite-temperature electroweak phase transition in the low-energy effective theory, finding that the possibility of a first-order electroweak phase transition is resurrected. We discuss the evolution of the Universe during this transition and derive an order-of-magnitude lower limit on the abundance of electroweak baryons in the absence of a cosmological asymmetry, which suggests that such an asymmetry would be necessary if the electroweak baryons are to provide the cosmological density of dark matter. We revisit estimates of the corresponding spin-independent dark matter scattering cross section, with a view to direct detection experiments.
[ { "created": "Fri, 18 Nov 2011 21:30:07 GMT", "version": "v1" }, { "created": "Mon, 5 Dec 2011 17:39:32 GMT", "version": "v2" } ]
2015-06-03
[ [ "Campbell", "Bruce A.", "" ], [ "Ellis", "John", "" ], [ "Olive", "Keith A.", "" ] ]
In many strongly-interacting models of electroweak symmetry breaking the lowest-lying observable particle is a pseudo-Goldstone boson of approximate scale symmetry, the pseudo-dilaton. Its interactions with Standard Model particles can be described using a low-energy effective nonlinear chiral Lagrangian supplemented by terms that restore approximate scale symmetry, yielding couplings of the pseudo-dilaton that differ from those of a Standard Model Higgs boson by fixed factors. We review the experimental constraints on such a pseudo-dilaton in light of new data from the LHC and elsewhere. The effective nonlinear chiral Lagrangian has Skyrmion solutions that may be identified with the `electroweak baryons' of the underlying strongly-interacting theory, whose nature may be revealed by the properties of the Skyrmions. We discuss the finite-temperature electroweak phase transition in the low-energy effective theory, finding that the possibility of a first-order electroweak phase transition is resurrected. We discuss the evolution of the Universe during this transition and derive an order-of-magnitude lower limit on the abundance of electroweak baryons in the absence of a cosmological asymmetry, which suggests that such an asymmetry would be necessary if the electroweak baryons are to provide the cosmological density of dark matter. We revisit estimates of the corresponding spin-independent dark matter scattering cross section, with a view to direct detection experiments.
2211.03804
Avital Dery
Avital Dery, Mitrajyoti Ghosh, Yuval Grossman, Teppei Kitahara and Stefan Schacht
A Precision Relation between $\Gamma(K\to\mu^+\mu^-)(t)$ and ${\cal B}(K_L\to\mu^+\mu^-)/{\cal B}(K_L\to\gamma\gamma)$
null
null
10.1007/JHEP03(2023)014
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We find that the phase appearing in the unitarity relation between $\mathcal{B}(K_L\rightarrow \mu^+\mu^-)$ and $\mathcal{B}(K_L\rightarrow \gamma\gamma)$ is equal to the phase shift in the interference term of the time-dependent $K\rightarrow \mu^+\mu^-$ decay. A probe of this relation at future kaon facilities constitutes a Standard Model test with a theory precision of about $2\%$. The phase has further importance for sensitivity studies regarding the measurement of the time-dependent $K\rightarrow \mu^+\mu^-$ decay rate to extract the CKM matrix element combination $\vert V_{ts} V_{td} \sin(\beta+\beta_s)\vert\approx A^2\lambda^5\bar\eta$. We find a model-independent theoretically clean prediction, $\cos^2\varphi_0 = 0.96 \pm 0.03$. The quoted error is a combination of the theoretical and experimental errors, and both of them are expected to shrink in the future. Using input from the large-$N_C$ limit within chiral perturbation theory, we find a theory preference towards solutions with negative $\cos\varphi_0$, reducing a four-fold ambiguity in the angle $\varphi_0$ to a two-fold one.
[ { "created": "Mon, 7 Nov 2022 19:00:03 GMT", "version": "v1" }, { "created": "Mon, 12 Jun 2023 15:44:39 GMT", "version": "v2" } ]
2023-06-13
[ [ "Dery", "Avital", "" ], [ "Ghosh", "Mitrajyoti", "" ], [ "Grossman", "Yuval", "" ], [ "Kitahara", "Teppei", "" ], [ "Schacht", "Stefan", "" ] ]
We find that the phase appearing in the unitarity relation between $\mathcal{B}(K_L\rightarrow \mu^+\mu^-)$ and $\mathcal{B}(K_L\rightarrow \gamma\gamma)$ is equal to the phase shift in the interference term of the time-dependent $K\rightarrow \mu^+\mu^-$ decay. A probe of this relation at future kaon facilities constitutes a Standard Model test with a theory precision of about $2\%$. The phase has further importance for sensitivity studies regarding the measurement of the time-dependent $K\rightarrow \mu^+\mu^-$ decay rate to extract the CKM matrix element combination $\vert V_{ts} V_{td} \sin(\beta+\beta_s)\vert\approx A^2\lambda^5\bar\eta$. We find a model-independent theoretically clean prediction, $\cos^2\varphi_0 = 0.96 \pm 0.03$. The quoted error is a combination of the theoretical and experimental errors, and both of them are expected to shrink in the future. Using input from the large-$N_C$ limit within chiral perturbation theory, we find a theory preference towards solutions with negative $\cos\varphi_0$, reducing a four-fold ambiguity in the angle $\varphi_0$ to a two-fold one.
hep-ph/9712461
Helmar Meier
Helmar Meier (1), Zlatko Halabuka (1), Kai Hencken (1), Dirk Trautmann (1), Gerhard Baur (2) ((1) Institut fuer Physik der Universitaet Basel, Switzerland, (2) Institut fuer Kernphysik (Theorie), Forschungszentrum Juelich, Germany)
Relativistic Antihydrogen Production
6 pages, LaTeX, 7 eps-figures, submitted to Euro. Phys. J. C
Eur.Phys.J.C5:287-291,1998
10.1007/s100520050271
null
hep-ph
null
We calculate the production of relativistic antihydrogen atoms by bound-free pair production. The cross section is calculated in the semiclassical approximation (SCA), or equivalently in the plane wave Born approximation (PWBA) using exact Dirac-Coulomb wave functions. We compare our calculations to the equivalent photon approximation (EPA).
[ { "created": "Fri, 19 Dec 1997 20:55:17 GMT", "version": "v1" } ]
2011-09-13
[ [ "Meier", "Helmar", "" ], [ "Halabuka", "Zlatko", "" ], [ "Hencken", "Kai", "" ], [ "Trautmann", "Dirk", "" ], [ "Baur", "Gerhard", "" ] ]
We calculate the production of relativistic antihydrogen atoms by bound-free pair production. The cross section is calculated in the semiclassical approximation (SCA), or equivalently in the plane wave Born approximation (PWBA) using exact Dirac-Coulomb wave functions. We compare our calculations to the equivalent photon approximation (EPA).
hep-ph/9306305
Herbert Weigel
J. Schlienz, H. Weigel, H. Reinhardt and R. Alkofer
The Nambu-Jona-Lasinio Chiral Soliton with Constrained Baryon Number
10 LaTeX pages 4 figures, report no UNITU-THEP-7/1993
Phys.Lett.B315:6-11,1993
10.1016/0370-2693(93)90149-C
null
hep-ph
null
A regularization for the baryon number consistent with the energy in the Nambu-Jona-Lasinio model is introduced. The soliton solution is constructed with the regularized baryon number constrained to unity. It is furthermore demonstrated that this constraint prevents the soliton from collapsing when scalar fields are allowed to be space dependent. In this scheme the scalar fields actually vanish at the origin reflecting a partial restoration of chiral symmetry. Also the influence of this constraint on some static properties of baryons is discussed.
[ { "created": "Wed, 23 Jun 1993 07:33:54 GMT", "version": "v1" } ]
2008-11-26
[ [ "Schlienz", "J.", "" ], [ "Weigel", "H.", "" ], [ "Reinhardt", "H.", "" ], [ "Alkofer", "R.", "" ] ]
A regularization for the baryon number consistent with the energy in the Nambu-Jona-Lasinio model is introduced. The soliton solution is constructed with the regularized baryon number constrained to unity. It is furthermore demonstrated that this constraint prevents the soliton from collapsing when scalar fields are allowed to be space dependent. In this scheme the scalar fields actually vanish at the origin reflecting a partial restoration of chiral symmetry. Also the influence of this constraint on some static properties of baryons is discussed.
1905.01529
Dennis Sivers Dr.
Dennis Sivers
SU(2) Charges with Spherical Symmetry and Confining Boundary Conditions
5 pages with no figures. This material was presented at the XIII Quark Confinement and the Hadron Spectrum--Confinement2018
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Applying the static Yang-Mills Maxwell equations to a simple system of SU(2) charges with spherical symmetry and confining boundary conditions provides for a demonstration of the likelihood that the confinement mechanism in non-Abelian gauge theories necessarily involves a topologically-charged domain wall consisting of a surface volume with CP-odd field strength density. The surface volume of a color-singlet system of SU(2) charges therefor describes the magnetic dual of a topological insulator. This essential topological structure in inextricably connected to the hadronic dynamics of the pion tornado. In analogy to the kink solution in the 1+1 dimensional Abelian Higgs model the classical solutions for the field equations in spherically symmetric SU(2) with this domain wall of topological charge can lead to a mass gap in the quantum system
[ { "created": "Sat, 4 May 2019 17:20:35 GMT", "version": "v1" } ]
2019-05-07
[ [ "Sivers", "Dennis", "" ] ]
Applying the static Yang-Mills Maxwell equations to a simple system of SU(2) charges with spherical symmetry and confining boundary conditions provides for a demonstration of the likelihood that the confinement mechanism in non-Abelian gauge theories necessarily involves a topologically-charged domain wall consisting of a surface volume with CP-odd field strength density. The surface volume of a color-singlet system of SU(2) charges therefor describes the magnetic dual of a topological insulator. This essential topological structure in inextricably connected to the hadronic dynamics of the pion tornado. In analogy to the kink solution in the 1+1 dimensional Abelian Higgs model the classical solutions for the field equations in spherically symmetric SU(2) with this domain wall of topological charge can lead to a mass gap in the quantum system
1801.04465
German Rodrigo
German Rodrigo, Felix Driencourt-Mangin, German F. R. Sborlini and Roger J. Hernandez-Pinto
Recent developments from the loop-tree duality
8 pages, 1 figure. Presented at 13th International Symposium on Radiative Corrections RADCOR2017, 24-29 September 2017, St. Gilgen, Austria
PoS(RADCOR2017)013
null
IFIC/18-01
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this talk, we review the most recent developments of the four-dimensional unsubstraction (FDU) and loop-tree duality (LTD) methods. In particular, we make emphasis on the advantages of the LTD formalism regarding asymptotic expansions of loop integrands.
[ { "created": "Sat, 13 Jan 2018 17:01:44 GMT", "version": "v1" } ]
2018-01-16
[ [ "Rodrigo", "German", "" ], [ "Driencourt-Mangin", "Felix", "" ], [ "Sborlini", "German F. R.", "" ], [ "Hernandez-Pinto", "Roger J.", "" ] ]
In this talk, we review the most recent developments of the four-dimensional unsubstraction (FDU) and loop-tree duality (LTD) methods. In particular, we make emphasis on the advantages of the LTD formalism regarding asymptotic expansions of loop integrands.
hep-ph/0004089
S. Atag
S. Atag and I.T. Cakir
Anomalous WW-Gamma Vertex in Gamma-p Collision
8 pages, 2 eps figures
Phys.Rev. D63 (2001) 033004
10.1103/PhysRevD.63.033004
null
hep-ph
null
The potential of LC+HERAp based Gamma-p collider to probe WW-Gamma vertex is presented through the discussion of sensitivity to anomalous couplings and P_T distribution of the final quark. The limits of -0.04<\Delta\kappa<0.04 and -0.11<\lambda<0.11 at 95% C.L. can be reached with integrated luminosity 200(1/pb). The limit for \Delta\kappa is comparable to one which is expected from LHC. The bounds are also obtained from corresponding ep collider using Weizsacker-Williams Approximation to compare with real photons.
[ { "created": "Mon, 10 Apr 2000 09:11:05 GMT", "version": "v1" } ]
2009-10-31
[ [ "Atag", "S.", "" ], [ "Cakir", "I. T.", "" ] ]
The potential of LC+HERAp based Gamma-p collider to probe WW-Gamma vertex is presented through the discussion of sensitivity to anomalous couplings and P_T distribution of the final quark. The limits of -0.04<\Delta\kappa<0.04 and -0.11<\lambda<0.11 at 95% C.L. can be reached with integrated luminosity 200(1/pb). The limit for \Delta\kappa is comparable to one which is expected from LHC. The bounds are also obtained from corresponding ep collider using Weizsacker-Williams Approximation to compare with real photons.
1306.6200
Sebastian Bodenstein Sebastian Bodenstein
S. Bodenstein
Precise Determinations of the Charm and Bottom Quark Masses
Talk given at the International Workshop on Determination of the Fundamental Parameters of QCD. To be published in Mod. Phys. Lett. A
null
10.1142/S0217732313600201
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A finite-energy sum-rule is presented that allows for the use of combinations of both positive- and inverse-moment integration kernels. The freedom afforded from being able to employ this large class of integration kernels in our sum-rule is then exploited to obtain the values of the charm and bottom masses with minimum total uncertainty. We obtain as our final results m_c(3 GeV)=986(13) MeV and m_b(10 GeV)=3617(25) MeV, which are amongst the most precise values of these parameters obtained by any method.
[ { "created": "Wed, 26 Jun 2013 11:02:44 GMT", "version": "v1" } ]
2015-06-16
[ [ "Bodenstein", "S.", "" ] ]
A finite-energy sum-rule is presented that allows for the use of combinations of both positive- and inverse-moment integration kernels. The freedom afforded from being able to employ this large class of integration kernels in our sum-rule is then exploited to obtain the values of the charm and bottom masses with minimum total uncertainty. We obtain as our final results m_c(3 GeV)=986(13) MeV and m_b(10 GeV)=3617(25) MeV, which are amongst the most precise values of these parameters obtained by any method.
hep-ph/9911265
U. Jentschura
U. D. Jentschura, J. Becher, E. J. Weniger, G. Soff
Resummation of QED Perturbation Series by Sequence Transformations and the Prediction of Perturbative Coefficients
4 pages, LaTeX, 3 tables; minor adjustments
Phys.Rev.Lett. 85 (2000) 2446-2449
10.1103/PhysRevLett.85.2446
null
hep-ph
null
We propose a method for the resummation of divergent perturbative expansions in quantum electrodynamics and related field theories. The method is based on a nonlinear sequence transformation and uses as input data only the numerical values of a finite number of perturbative coefficients. The results obtained in this way are for alternating series superior to those obtained using Pad\'{e} approximants. The nonlinear sequence transformation fulfills an accuracy-through-order relation and can be used to predict perturbative coefficients. In many cases, these predictions are closer to available analytic results than predictions obtained using the Pad\'{e} method.
[ { "created": "Mon, 8 Nov 1999 17:03:24 GMT", "version": "v1" }, { "created": "Sun, 6 Aug 2000 19:38:04 GMT", "version": "v2" } ]
2009-10-31
[ [ "Jentschura", "U. D.", "" ], [ "Becher", "J.", "" ], [ "Weniger", "E. J.", "" ], [ "Soff", "G.", "" ] ]
We propose a method for the resummation of divergent perturbative expansions in quantum electrodynamics and related field theories. The method is based on a nonlinear sequence transformation and uses as input data only the numerical values of a finite number of perturbative coefficients. The results obtained in this way are for alternating series superior to those obtained using Pad\'{e} approximants. The nonlinear sequence transformation fulfills an accuracy-through-order relation and can be used to predict perturbative coefficients. In many cases, these predictions are closer to available analytic results than predictions obtained using the Pad\'{e} method.
1911.11039
Keval Gandhi
Keval Gandhi and Ajay Kumar Rai
Spectrum of strange singly charmed baryons in the constituent quark model
26 pages (submitted in EPJP)
Eur. Phys. J. Plus (2020) 135:213
10.1140/epjp/s13360-020-00141-0
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Excited states masses of the strange singly charmed baryons are calculated using the non-relativistic approach of hypercentral Constituent Quark Model (hCQM). The hyper-Coulomb plus screened potential is used as a confinement potential with the first order correction. The spin-spin, spin-orbit and spin-tensor interaction terms are included perturbatively. Our calculated masses are allowed to construct the Regge trajectories in both $(n_r, M^2)$ and $(J, M^2)$ planes. The mass spectra and the Regge trajectories study predict the spin-parity of $\Xi{_c(2970)^{+/0}}$, $\Xi{_c(3080)^{+/0}}$, $\Xi{_c(3123)^+}$, $\Omega{_c}(3000)^0$ and $\Omega{_c}(3119)^0$ baryons. Moreover, the strong one pion decay rates of the isodoublet states of $\Xi{_c(2645)}$, $\Xi{_c(2790)}$ and $\Xi{_c(2815)}$ are analyzed in the framework of Heavy Hadron Chiral Perturbation Theory (HHChPT). Also, the ground state magnetic moments and the radiative decay rates based on the transition magnetic moments are calculated in the framework of constituent quark model.
[ { "created": "Mon, 25 Nov 2019 16:51:49 GMT", "version": "v1" } ]
2020-03-20
[ [ "Gandhi", "Keval", "" ], [ "Rai", "Ajay Kumar", "" ] ]
Excited states masses of the strange singly charmed baryons are calculated using the non-relativistic approach of hypercentral Constituent Quark Model (hCQM). The hyper-Coulomb plus screened potential is used as a confinement potential with the first order correction. The spin-spin, spin-orbit and spin-tensor interaction terms are included perturbatively. Our calculated masses are allowed to construct the Regge trajectories in both $(n_r, M^2)$ and $(J, M^2)$ planes. The mass spectra and the Regge trajectories study predict the spin-parity of $\Xi{_c(2970)^{+/0}}$, $\Xi{_c(3080)^{+/0}}$, $\Xi{_c(3123)^+}$, $\Omega{_c}(3000)^0$ and $\Omega{_c}(3119)^0$ baryons. Moreover, the strong one pion decay rates of the isodoublet states of $\Xi{_c(2645)}$, $\Xi{_c(2790)}$ and $\Xi{_c(2815)}$ are analyzed in the framework of Heavy Hadron Chiral Perturbation Theory (HHChPT). Also, the ground state magnetic moments and the radiative decay rates based on the transition magnetic moments are calculated in the framework of constituent quark model.
hep-ph/9506423
null
A.D. Martin, W.J. Stirling and R.G. Roberts
The $\alpha_S$ Dependence of Parton Distributions
8 pages 6 figures
Phys.Lett. B356 (1995) 89-94
10.1016/0370-2693(95)00808-X
RAL-TR-95-013, DTP/95/48
hep-ph
null
We perform next-to-leading order global analyses of deep inelastic and related data for different fixed values of $\alpha_S (M_Z^2)$. We present sets of parton distributions for six values of $\alpha_S$ in the range 0.105 to 0.130. We display the $(x, Q^2)$ domains with the largest parton uncertainty and we discuss how forthcoming data may be able to improve the determination of the parton densities.
[ { "created": "Mon, 26 Jun 1995 15:13:34 GMT", "version": "v1" } ]
2009-10-28
[ [ "Martin", "A. D.", "" ], [ "Stirling", "W. J.", "" ], [ "Roberts", "R. G.", "" ] ]
We perform next-to-leading order global analyses of deep inelastic and related data for different fixed values of $\alpha_S (M_Z^2)$. We present sets of parton distributions for six values of $\alpha_S$ in the range 0.105 to 0.130. We display the $(x, Q^2)$ domains with the largest parton uncertainty and we discuss how forthcoming data may be able to improve the determination of the parton densities.
hep-ph/0402254
Karl Jakobs
S.Asai, G.Azuelos, C.Buttar, V.Cavasinni, D.Costanzo, K.Cranmer, R.Harper, K.Jakobs, J.Kanzaki, M.Klute, R.Mazini, B.Mellado, W.Quayle, E.Richter-Was, T.Takemoto, I.Vivarelli, Sau Lan Wu
Prospects for the Search for a Standard Model Higgs Boson in ATLAS using Vector Boson Fusion
20 pages, 13 ps figures, uses EPJ style file
Eur.Phys.J.C32S2:19-54,2004
10.1140/epjcd/s2003-01-010-8
null
hep-ph
null
The potential for the discovery of a Standard Model Higgs boson in the mass range m_H < 2 m_Z in the vector boson fusion mode has been studied for the ATLAS experiment at the LHC. The characteristic signatures of additional jets in the forward regions of the detector and of low jet activity in the central region allow for an efficient background rejection. Analyses for the H -> WW and H -> tau tau decay modes have been performed using a realistic simulation of the expected detector performance. The results obtained demonstrate the large discovery potential in the H -> WW decay channel and the sensitivity to Higgs boson decays into tau-pairs in the low-mass region around 120 GeV.
[ { "created": "Tue, 24 Feb 2004 18:25:17 GMT", "version": "v1" } ]
2011-09-13
[ [ "Asai", "S.", "" ], [ "Azuelos", "G.", "" ], [ "Buttar", "C.", "" ], [ "Cavasinni", "V.", "" ], [ "Costanzo", "D.", "" ], [ "Cranmer", "K.", "" ], [ "Harper", "R.", "" ], [ "Jakobs", "K.", "" ], [ "Kanzaki", "J.", "" ], [ "Klute", "M.", "" ], [ "Mazini", "R.", "" ], [ "Mellado", "B.", "" ], [ "Quayle", "W.", "" ], [ "Richter-Was", "E.", "" ], [ "Takemoto", "T.", "" ], [ "Vivarelli", "I.", "" ], [ "Wu", "Sau Lan", "" ] ]
The potential for the discovery of a Standard Model Higgs boson in the mass range m_H < 2 m_Z in the vector boson fusion mode has been studied for the ATLAS experiment at the LHC. The characteristic signatures of additional jets in the forward regions of the detector and of low jet activity in the central region allow for an efficient background rejection. Analyses for the H -> WW and H -> tau tau decay modes have been performed using a realistic simulation of the expected detector performance. The results obtained demonstrate the large discovery potential in the H -> WW decay channel and the sensitivity to Higgs boson decays into tau-pairs in the low-mass region around 120 GeV.
0812.4122
Serguei Molodtsov
S.V. Molodtsov, G.M. Zinovjev
Some peculiarities in response on filling up the Fermi sphere by quarks
11 pages, 5 figures, minor language improvement
null
10.1209/0295-5075/87/61001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Considering quarks as the quasi-particles of the model Hamiltonian with four-fermion interaction we study response on the process of filling up the Fermi sphere by quarks.
[ { "created": "Mon, 22 Dec 2008 08:45:51 GMT", "version": "v1" }, { "created": "Tue, 10 Feb 2009 18:51:02 GMT", "version": "v2" } ]
2015-05-13
[ [ "Molodtsov", "S. V.", "" ], [ "Zinovjev", "G. M.", "" ] ]
Considering quarks as the quasi-particles of the model Hamiltonian with four-fermion interaction we study response on the process of filling up the Fermi sphere by quarks.
1807.02727
Juan Carlos G\'omez Izquierdo
E. A. Garc\'es, Juan Carlos G\'omez-Izquierdo and F. Gonzalez-Canales
Flavored Non-Minimal Left-Right Symmetric Model Fermion Masses and Mixings
23 pages, 9 figures. references added, typos corrected, JCGI added his current institution;conclusions rewrote and unchanged results. Version published in European Physical Journal C
Eur.Phys.J. C78 (2018) no.10, 812
10.1140/epjc/s10052-018-6271-5
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A complete study on the fermion masses and flavor mixing is presented in a non-minimal left-right symmetric model (NMLRMS) where the ${\bf S}_{3}\otimes {\bf Z}_{2}\otimes {\bf Z}^{e}_{2}$ flavor symmetry drives the Yukawa couplings. In the quark sector, the mass matrices possess a kind of the generalized Fritzsch textures that allow us to fit the CKM mixing matrix in good agreement to the last experimental data. In the lepton sector, on the other hand, a soft breaking of the $\mu\leftrightarrow \tau$ symmetry provides a non zero and non maximal reactor and atmospheric angles, respectively. The inverted and degenerate hierarchy are favored in the model where a set of free parameters is found to be consistent with the current neutrino data.
[ { "created": "Sat, 7 Jul 2018 23:42:02 GMT", "version": "v1" }, { "created": "Tue, 17 Jul 2018 01:48:18 GMT", "version": "v2" }, { "created": "Sun, 28 Oct 2018 01:32:26 GMT", "version": "v3" } ]
2018-10-30
[ [ "Garcés", "E. A.", "" ], [ "Gómez-Izquierdo", "Juan Carlos", "" ], [ "Gonzalez-Canales", "F.", "" ] ]
A complete study on the fermion masses and flavor mixing is presented in a non-minimal left-right symmetric model (NMLRMS) where the ${\bf S}_{3}\otimes {\bf Z}_{2}\otimes {\bf Z}^{e}_{2}$ flavor symmetry drives the Yukawa couplings. In the quark sector, the mass matrices possess a kind of the generalized Fritzsch textures that allow us to fit the CKM mixing matrix in good agreement to the last experimental data. In the lepton sector, on the other hand, a soft breaking of the $\mu\leftrightarrow \tau$ symmetry provides a non zero and non maximal reactor and atmospheric angles, respectively. The inverted and degenerate hierarchy are favored in the model where a set of free parameters is found to be consistent with the current neutrino data.
1709.06103
Wei Su
Jiayin Gu, Honglei Li, Zhen Liu, Shufang Su, Wei Su
Learning from Higgs Physics at Future Higgs Factories
42 pages
null
10.1007/JHEP12(2017)153
FERMILAB-PUB-17-348-T,DESY 17-130
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Future Higgs factories can reach impressive precision on Higgs property measurements. In this paper, instead of conventional focus of Higgs precision in certain interaction bases, we explored its sensitivity to new physics models at the electron-positron colliders. In particular, we studied two categories of new physics models, Standard Model (SM) with a real scalar singlet extension, and Two Higgs Double Model (2HDM) as examples of weakly-interacting models, Minimal Composite Higgs Model (MCHM) and three typical patterns of the more general operator counting for strong interacting models as examples of strong dynamics. We performed a global fit to various Higgs search channels to obtain the 95% C.L. constraints on the model parameter space. In the SM with a singlet extension, we obtained the limits on the singlet-doublet mixing angle sin(theta), as well as the more general Wilson coefficients of the induced higher dimensional operators. In the 2HDM, we analyzed tree level effects in tan(beta) vs. cos(beta-alpha) plane, as well as the one-loop contributions from the heavy Higgs bosons in the alignment limit to obtain the constraints on heavy Higgs masses for different types of 2HDM. In strong dynamics models, we obtained lower limits on the strong dynamics scale. In addition, once deviations of Higgs couplings are observed, they can be used to distinguish different models. We also compared the sensitivity of various future Higgs factories, namely Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC).
[ { "created": "Mon, 18 Sep 2017 18:01:06 GMT", "version": "v1" } ]
2019-08-17
[ [ "Gu", "Jiayin", "" ], [ "Li", "Honglei", "" ], [ "Liu", "Zhen", "" ], [ "Su", "Shufang", "" ], [ "Su", "Wei", "" ] ]
Future Higgs factories can reach impressive precision on Higgs property measurements. In this paper, instead of conventional focus of Higgs precision in certain interaction bases, we explored its sensitivity to new physics models at the electron-positron colliders. In particular, we studied two categories of new physics models, Standard Model (SM) with a real scalar singlet extension, and Two Higgs Double Model (2HDM) as examples of weakly-interacting models, Minimal Composite Higgs Model (MCHM) and three typical patterns of the more general operator counting for strong interacting models as examples of strong dynamics. We performed a global fit to various Higgs search channels to obtain the 95% C.L. constraints on the model parameter space. In the SM with a singlet extension, we obtained the limits on the singlet-doublet mixing angle sin(theta), as well as the more general Wilson coefficients of the induced higher dimensional operators. In the 2HDM, we analyzed tree level effects in tan(beta) vs. cos(beta-alpha) plane, as well as the one-loop contributions from the heavy Higgs bosons in the alignment limit to obtain the constraints on heavy Higgs masses for different types of 2HDM. In strong dynamics models, we obtained lower limits on the strong dynamics scale. In addition, once deviations of Higgs couplings are observed, they can be used to distinguish different models. We also compared the sensitivity of various future Higgs factories, namely Circular Electron Positron Collider (CEPC), Future Circular Collider (FCC)-ee and International Linear Collider (ILC).
hep-ph/0604109
Abdelhak Djouadi
Abdelhak Djouadi
Tests of the Higgs properties at the next colliders
8 pages, 4 figures. Talk presented at PLC2005 Warsaw and Kazimierz Lectures, 5/09-08/09 2005
Acta Phys.Polon. B37 (2006) 1367
null
null
hep-ph
null
We discuss the tests of the fundamental properties of the Standard Model Higgs boson that can be performed in the next round of experiments.
[ { "created": "Wed, 12 Apr 2006 15:06:20 GMT", "version": "v1" } ]
2007-05-23
[ [ "Djouadi", "Abdelhak", "" ] ]
We discuss the tests of the fundamental properties of the Standard Model Higgs boson that can be performed in the next round of experiments.
1503.08216
Otto Eberhardt
Debtosh Chowdhury, Otto Eberhardt
Global fits of the two-loop renormalized Two-Higgs-Doublet model with soft $Z_2$ breaking
30 pages, 29 figures. Major update of the experimental inputs; references added
null
10.1007/JHEP11(2015)052
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We determine the next-to-leading order renormalization group equations for the Two-Higgs-Doublet model with a softly broken $Z_2$ symmetry and CP conservation in the scalar potential. We use them to identify the parameter regions which are stable up to the Planck scale and find that in this case the quartic couplings of the Higgs potential cannot be larger than 1 in magnitude and that the absolute values of the S-matrix eigenvalues cannot exceed 2.5 at the electroweak symmetry breaking scale. Interpreting the 125 GeV resonance as the light CP-even Higgs eigenstate, we combine stability constraints, electroweak precision and flavour observables with the latest ATLAS and CMS data on Higgs signal strengths and heavy Higgs searches in global parameter fits to all four types of $Z_2$ symmetry. We quantify the maximal deviations from the alignment limit and find that in type II and Y the mass of the heavy CP-even (CP-odd) scalar cannot be smaller than 340 GeV (360 GeV). Also, we pinpoint the physical parameter regions compatible with a stable scalar potential up to the Planck scale. Motivated by the question how natural a Higgs mass of 125 GeV can be in the context of a Two-Higgs-Doublet model, we also address the hierarchy problem and find that the Two-Higgs-Doublet model does not offer a perturbative solution to it beyond 5 TeV.
[ { "created": "Fri, 27 Mar 2015 20:00:53 GMT", "version": "v1" }, { "created": "Wed, 10 Jun 2015 17:29:54 GMT", "version": "v2" } ]
2016-01-20
[ [ "Chowdhury", "Debtosh", "" ], [ "Eberhardt", "Otto", "" ] ]
We determine the next-to-leading order renormalization group equations for the Two-Higgs-Doublet model with a softly broken $Z_2$ symmetry and CP conservation in the scalar potential. We use them to identify the parameter regions which are stable up to the Planck scale and find that in this case the quartic couplings of the Higgs potential cannot be larger than 1 in magnitude and that the absolute values of the S-matrix eigenvalues cannot exceed 2.5 at the electroweak symmetry breaking scale. Interpreting the 125 GeV resonance as the light CP-even Higgs eigenstate, we combine stability constraints, electroweak precision and flavour observables with the latest ATLAS and CMS data on Higgs signal strengths and heavy Higgs searches in global parameter fits to all four types of $Z_2$ symmetry. We quantify the maximal deviations from the alignment limit and find that in type II and Y the mass of the heavy CP-even (CP-odd) scalar cannot be smaller than 340 GeV (360 GeV). Also, we pinpoint the physical parameter regions compatible with a stable scalar potential up to the Planck scale. Motivated by the question how natural a Higgs mass of 125 GeV can be in the context of a Two-Higgs-Doublet model, we also address the hierarchy problem and find that the Two-Higgs-Doublet model does not offer a perturbative solution to it beyond 5 TeV.
hep-ph/0111196
Andrzej Rostworowski
M. Praszalowicz, A. Rostworowski (Jagellonian University, Cracow, Poland)
Vacuum condensates and the pion wave functions in the nonlocal chiral model
12 pages, 7 figures; three new paragraphs added: one (in sec. IV) discusses the relation between quark and gluon condensates, the other two (in secs. I and VI) clarify the difference between the normalisation scale Q_0, at which the condensates are evaluated, and the model parameter Lambda; new references added; to be published in Phys. Rev. D
Phys.Rev. D66 (2002) 054002
10.1103/PhysRevD.66.054002
TPJU-10/2001
hep-ph
null
We use the simple instanton motivated Nambu Jona-Lasinio - type model to calculate a twist 3 pseudoscalar pion light cone wave function. Using normalisation condition for this wave function we calculate the quark condensate and also the gluon condensate, which agree with the phenomenological values for these quantities. Since we can compute also the k_T^2 dependence of the light cone wave functions, we calculate k_T^2 moments of the pseudo-scalar and axial-vector wave functions which are related to the mixed vacuum condensates. This allows us to extract the condensates and compare them with existing estimates.
[ { "created": "Thu, 15 Nov 2001 18:39:28 GMT", "version": "v1" }, { "created": "Thu, 11 Jul 2002 12:02:39 GMT", "version": "v2" } ]
2009-11-07
[ [ "Praszalowicz", "M.", "", "Jagellonian University, Cracow,\n Poland" ], [ "Rostworowski", "A.", "", "Jagellonian University, Cracow,\n Poland" ] ]
We use the simple instanton motivated Nambu Jona-Lasinio - type model to calculate a twist 3 pseudoscalar pion light cone wave function. Using normalisation condition for this wave function we calculate the quark condensate and also the gluon condensate, which agree with the phenomenological values for these quantities. Since we can compute also the k_T^2 dependence of the light cone wave functions, we calculate k_T^2 moments of the pseudo-scalar and axial-vector wave functions which are related to the mixed vacuum condensates. This allows us to extract the condensates and compare them with existing estimates.
1408.0086
Chao Wang
Chao Wang, Xin-Heng Guo, Ying Liu, Rui-Cheng Li
Direct CP violation in $\tau^\pm\rightarrow K^\pm \rho^0 (\omega)\nu_\tau \rightarrow K^\pm \pi^+\pi^-\nu_\tau $
null
Eur.Phys.J. C74 (2014) 11, 3140
10.1140/epjc/s10052-014-3140-8
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the direct CP violation in the $\tau^\pm\rightarrow K^\pm \rho^0 (\omega)\nu_\tau \rightarrow K^\pm \pi^+\pi^-\nu_\tau$ decay process in the Standard Model. An interesting mechanism involving the charge symmetry violating mixing between $\rho^0$ and $\omega$ is applied to enlarge the CP asymmetry. With this mechanism, the maximum differential and localized integrated CP asymmetries can reach $-(5.6^{+2.9}_{-1.7})\times10^{-12}$ and $6.3^{+2.4}_{-3.3}\times 10^{-11}$, respectively, which still leave plenty room for CP-violating New Physics to be discovered through this process.
[ { "created": "Fri, 1 Aug 2014 06:14:40 GMT", "version": "v1" } ]
2015-06-02
[ [ "Wang", "Chao", "" ], [ "Guo", "Xin-Heng", "" ], [ "Liu", "Ying", "" ], [ "Li", "Rui-Cheng", "" ] ]
We study the direct CP violation in the $\tau^\pm\rightarrow K^\pm \rho^0 (\omega)\nu_\tau \rightarrow K^\pm \pi^+\pi^-\nu_\tau$ decay process in the Standard Model. An interesting mechanism involving the charge symmetry violating mixing between $\rho^0$ and $\omega$ is applied to enlarge the CP asymmetry. With this mechanism, the maximum differential and localized integrated CP asymmetries can reach $-(5.6^{+2.9}_{-1.7})\times10^{-12}$ and $6.3^{+2.4}_{-3.3}\times 10^{-11}$, respectively, which still leave plenty room for CP-violating New Physics to be discovered through this process.
hep-ph/0509028
Domenico Falcone
D.Falcone
Quark-lepton symmetry and complementarity
7 pages, RevTex4
Mod.Phys.Lett. A21 (2006) 1815-1820
10.1142/S0217732306021128
DSF-22/2005
hep-ph
null
We argue that the difference between the observed approximate quark-lepton complementarity and the theoretical prediction based on realistic quark-lepton symmetry within the seesaw mechanism may be adjusted by means of a triplet contribution in the seesaw formula.
[ { "created": "Sun, 4 Sep 2005 14:40:55 GMT", "version": "v1" } ]
2009-11-11
[ [ "Falcone", "D.", "" ] ]
We argue that the difference between the observed approximate quark-lepton complementarity and the theoretical prediction based on realistic quark-lepton symmetry within the seesaw mechanism may be adjusted by means of a triplet contribution in the seesaw formula.
1303.6918
P. S. Bhupal Dev
K.S. Babu, P.S. Bhupal Dev, Elaine C.F.S. Fortes and R.N. Mohapatra
Post-Sphaleron Baryogenesis and an Upper Limit on the Neutron-Antineutron Oscillation Time
22 pages, 3 tables, 10 figures; clarification added on the baryogenesis calculation; version accepted for publication in Phys. Rev. D
null
10.1103/PhysRevD.87.115019
OSU-HEP-13-02, MAN/HEP/2012/017, UMD-PP-013-003
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A recently proposed scenario for baryogenesis, called post--sphaleron baryogenesis (PSB) is discussed within a class of quark--lepton unified framework based on the gauge symmetry SU(2)_L x SU(2)_R x SU(4)_c realized in the multi--TeV scale. The baryon asymmetry of the universe in this model is produced below the electroweak phase transition temperature after the sphalerons have decoupled from the Hubble expansion. These models embed naturally the seesaw mechanism for neutrino masses, and predict color-sextet scalar particles in the TeV range which may be accessible to the LHC experiments. A necessary consequence of this scenario is the baryon number violating \Delta B=2 process of neutron--antineutron (n-\bar{n}) oscillations. In this paper we show that the constraints of PSB, when combined with the neutrino oscillation data and restrictions from flavor changing neutral currents mediated by the colored scalars imply an upper limit on the n-\bar{n} oscillation time of 5 x 10^{10} sec. regardless of the quark--lepton unification scale. If this scale is relatively low, in the (200-250) TeV range, \tau_{n-\bar{n}} is predicted to be less than 10^{10} sec., which is accessible to the next generation of proposed experiments.
[ { "created": "Wed, 27 Mar 2013 18:12:41 GMT", "version": "v1" }, { "created": "Thu, 6 Jun 2013 14:56:17 GMT", "version": "v2" } ]
2013-06-26
[ [ "Babu", "K. S.", "" ], [ "Dev", "P. S. Bhupal", "" ], [ "Fortes", "Elaine C. F. S.", "" ], [ "Mohapatra", "R. N.", "" ] ]
A recently proposed scenario for baryogenesis, called post--sphaleron baryogenesis (PSB) is discussed within a class of quark--lepton unified framework based on the gauge symmetry SU(2)_L x SU(2)_R x SU(4)_c realized in the multi--TeV scale. The baryon asymmetry of the universe in this model is produced below the electroweak phase transition temperature after the sphalerons have decoupled from the Hubble expansion. These models embed naturally the seesaw mechanism for neutrino masses, and predict color-sextet scalar particles in the TeV range which may be accessible to the LHC experiments. A necessary consequence of this scenario is the baryon number violating \Delta B=2 process of neutron--antineutron (n-\bar{n}) oscillations. In this paper we show that the constraints of PSB, when combined with the neutrino oscillation data and restrictions from flavor changing neutral currents mediated by the colored scalars imply an upper limit on the n-\bar{n} oscillation time of 5 x 10^{10} sec. regardless of the quark--lepton unification scale. If this scale is relatively low, in the (200-250) TeV range, \tau_{n-\bar{n}} is predicted to be less than 10^{10} sec., which is accessible to the next generation of proposed experiments.
hep-ph/0011282
Torbjorn Sjostrand
Johann Dischler and Torbj\"orn Sj\"ostrand
A Toy Model of Colour Screening in the Proton
LaTeX2e, 9 pages, 2 eps figures
Eur.Phys.J.direct C3:2,2001
null
LU TP 00-47
hep-ph
null
In hadronic collisions, the mini-jet cross section is formally divergent in the limit pT -> 0. We argue that this divergence is tamed by some effective colour correlation length scale of the hadron. A toy model of the hadronic structure is introduced, that allows an estimate of the screening effects, and especially their energy dependence.
[ { "created": "Wed, 22 Nov 2000 14:52:23 GMT", "version": "v1" } ]
2011-02-15
[ [ "Dischler", "Johann", "" ], [ "Sjöstrand", "Torbjörn", "" ] ]
In hadronic collisions, the mini-jet cross section is formally divergent in the limit pT -> 0. We argue that this divergence is tamed by some effective colour correlation length scale of the hadron. A toy model of the hadronic structure is introduced, that allows an estimate of the screening effects, and especially their energy dependence.
1210.3331
Shehu AbdusSalam
Shehu S. AbdusSalam, Debajyoti Choudhury
Higgs boson discovery versus sparticles prediction: Impact on the pMSSM's posterior samples from a Bayesian global fit
v2: added references and minor changes, published version
UJPA Vol. 2(3) pp.155 - 164, 2014
10.13189/ujpa.2014.020303
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The signal strength of the recently discovered Higgs boson-like particle in the diphoton channel seemingly constrains physics beyond the standard model to a severe degree. However, the reported signal strength is prone to possible underestimation of uncertainties. We propose a discriminant that is relatively free of many of the theoretical uncertainties, and use this to gauge the impact on the phenomenological MSSM. A Bayesian global fit to all the pre-LHC data results in posterior distributions for the masses that are neither very restrictive, nor sufficiently prior-independent (except for the Higgs and stop masses). The imposition of the Higgs data, on the other hand, yields interesting and nearly prior-independent constraints. In particular, the existence of some light superpartners is favoured.
[ { "created": "Thu, 11 Oct 2012 19:22:12 GMT", "version": "v1" }, { "created": "Wed, 5 Feb 2014 11:02:38 GMT", "version": "v2" } ]
2014-02-06
[ [ "AbdusSalam", "Shehu S.", "" ], [ "Choudhury", "Debajyoti", "" ] ]
The signal strength of the recently discovered Higgs boson-like particle in the diphoton channel seemingly constrains physics beyond the standard model to a severe degree. However, the reported signal strength is prone to possible underestimation of uncertainties. We propose a discriminant that is relatively free of many of the theoretical uncertainties, and use this to gauge the impact on the phenomenological MSSM. A Bayesian global fit to all the pre-LHC data results in posterior distributions for the masses that are neither very restrictive, nor sufficiently prior-independent (except for the Higgs and stop masses). The imposition of the Higgs data, on the other hand, yields interesting and nearly prior-independent constraints. In particular, the existence of some light superpartners is favoured.
1205.5317
Zhi-Gang Wang
Zhi-Gang Wang
The $B_c$-decays $B_c^+ \to J/\psi \pi^+\pi^-\pi^+$, $\eta_c \pi^+\pi^-\pi^+ $
9 pages, 6 figures, slight revision
Phys. Rev. D86 (2012) 054010
10.1103/PhysRevD.86.054010
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this article, we study the three-pion $B_c$-decays $B_c^+ \to J/\psi\, \pi^+\pi^-\pi^+$, $\eta_c\, \pi^+\pi^-\pi^+ $ with dominance of the intermediate axial-vector meson $a_1(1260)$ and vector meson $\rho(770)$ in the $\pi^+\pi^-\pi^+$ and $\pi^+\pi^-$ invariant mass distributions respectively, and make predictions for the branching fractions and differential decay widths. The ratio between the decays $B_c^+ \to J/\psi\, \pi^+\pi^-\pi^+$ and $B_c^+ \to J/\psi\, \pi^+ $ is compatible with the experimental data within uncertainties, other predictions can be confronted with the experimental data in the future at the LHCb.
[ { "created": "Thu, 24 May 2012 01:41:30 GMT", "version": "v1" }, { "created": "Mon, 23 Jul 2012 13:26:11 GMT", "version": "v2" }, { "created": "Sun, 19 Aug 2012 00:11:08 GMT", "version": "v3" } ]
2012-09-14
[ [ "Wang", "Zhi-Gang", "" ] ]
In this article, we study the three-pion $B_c$-decays $B_c^+ \to J/\psi\, \pi^+\pi^-\pi^+$, $\eta_c\, \pi^+\pi^-\pi^+ $ with dominance of the intermediate axial-vector meson $a_1(1260)$ and vector meson $\rho(770)$ in the $\pi^+\pi^-\pi^+$ and $\pi^+\pi^-$ invariant mass distributions respectively, and make predictions for the branching fractions and differential decay widths. The ratio between the decays $B_c^+ \to J/\psi\, \pi^+\pi^-\pi^+$ and $B_c^+ \to J/\psi\, \pi^+ $ is compatible with the experimental data within uncertainties, other predictions can be confronted with the experimental data in the future at the LHCb.
hep-ph/0011370
Spanos Vassilis
A. Katsikatsou, A.B. Lahanas, D.V Nanopoulos and V.C. Spanos
On the Radiative Corrections to the Pseudo-scalar Higgs Boson Mass
13 pages, 3 figures, minor corrections
Phys.Lett. B501 (2001) 69-77
10.1016/S0370-2693(01)00105-8
null
hep-ph
null
We reexamine the one-loop corrections to the mass of the pseudo-scalar Higgs boson, using the effective potential. In the absence of the chargino and neutralino contributions its mass exhibits a large scale dependence in the large $M_{1/2}$ regime, especially for values of $\tan \beta>20$. Thus, although of electroweak origin, the heaviness of the $M_{1/2}$, in conjunction with the largeness of $\tan \beta$, makes these corrections very important for establishing a scale independent result and an unambiguous determination of the pseudo-scalar mass in this region of the parameter space.
[ { "created": "Wed, 29 Nov 2000 21:14:19 GMT", "version": "v1" }, { "created": "Tue, 5 Dec 2000 11:15:55 GMT", "version": "v2" }, { "created": "Wed, 27 Dec 2000 15:14:53 GMT", "version": "v3" } ]
2009-10-31
[ [ "Katsikatsou", "A.", "" ], [ "Lahanas", "A. B.", "" ], [ "Nanopoulos", "D. V", "" ], [ "Spanos", "V. C.", "" ] ]
We reexamine the one-loop corrections to the mass of the pseudo-scalar Higgs boson, using the effective potential. In the absence of the chargino and neutralino contributions its mass exhibits a large scale dependence in the large $M_{1/2}$ regime, especially for values of $\tan \beta>20$. Thus, although of electroweak origin, the heaviness of the $M_{1/2}$, in conjunction with the largeness of $\tan \beta$, makes these corrections very important for establishing a scale independent result and an unambiguous determination of the pseudo-scalar mass in this region of the parameter space.
hep-ph/0101248
Johan Rathsman
Johan Rathsman
Conformal Expansions: A Template for QCD Predictions
16 pages, Invited talk given at RADCOR-2000, Carmel CA, USA, 11-15 September, 2000
null
null
CERN-TH/2001-015
hep-ph
null
The use of conformal expansions for predictions in quantum chromodynamics is discussed as a way to avoid renormalization scheme and scale ambiguities, as well as factorial growth of perturbative coefficients due to renormalons. Special emphasis is given to the properties of an assumed skeleton expansion and its relation to the Banks-Zaks expansion. The relation of BLM scale-setting to the skeleton expansion is also discussed and new criteria for the applicability of BLM scale-setting are presented.
[ { "created": "Mon, 22 Jan 2001 18:11:12 GMT", "version": "v1" } ]
2007-05-23
[ [ "Rathsman", "Johan", "" ] ]
The use of conformal expansions for predictions in quantum chromodynamics is discussed as a way to avoid renormalization scheme and scale ambiguities, as well as factorial growth of perturbative coefficients due to renormalons. Special emphasis is given to the properties of an assumed skeleton expansion and its relation to the Banks-Zaks expansion. The relation of BLM scale-setting to the skeleton expansion is also discussed and new criteria for the applicability of BLM scale-setting are presented.
1202.0724
Michael Buballa
Klaus Heckmann, Michael Buballa, Jochen Wambach
Chiral restoration effects on the shear viscosity of a pion gas
15 pages, 12 figures; v2: extended discussions of the dressed sigma propagator and the low-temperature limit, typos corrected, accepted version
Eur. Phys. J. A (2012) 48: 142
10.1140/epja/i2012-12142-2
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the shear viscosity of a pion gas in relativistic kinetic theory, using the Nambu-Jona-Lasinio model to construct the pion mass and the pi-pi interaction at finite temperature. Whereas at low temperatures the scattering properties and, hence, the viscosity are in agreement with lowest-order chiral perturbation theory, we find strong medium modifications in the crossover region. Here the system is strongly coupled and the scattering lengths diverge, similarly as for ultra-cold Fermi gases at a Feshbach resonance. As a consequence, the ratio eta/s is found to be strongly reduced as compared to calculations without medium-modified masses and scattering amplitudes. However, the quantitative results are very sensitive to the details of the applied approximations.
[ { "created": "Fri, 3 Feb 2012 15:01:22 GMT", "version": "v1" }, { "created": "Mon, 29 Oct 2012 18:00:21 GMT", "version": "v2" } ]
2012-11-07
[ [ "Heckmann", "Klaus", "" ], [ "Buballa", "Michael", "" ], [ "Wambach", "Jochen", "" ] ]
We investigate the shear viscosity of a pion gas in relativistic kinetic theory, using the Nambu-Jona-Lasinio model to construct the pion mass and the pi-pi interaction at finite temperature. Whereas at low temperatures the scattering properties and, hence, the viscosity are in agreement with lowest-order chiral perturbation theory, we find strong medium modifications in the crossover region. Here the system is strongly coupled and the scattering lengths diverge, similarly as for ultra-cold Fermi gases at a Feshbach resonance. As a consequence, the ratio eta/s is found to be strongly reduced as compared to calculations without medium-modified masses and scattering amplitudes. However, the quantitative results are very sensitive to the details of the applied approximations.
1808.00410
Fabian Rennecke
Wei-jie Fu, Jan M. Pawlowski, Fabian Rennecke
Strangeness Neutrality and QCD Thermodynamics
21 pages, 24 figures
SciPost Phys. Core 2, 002 (2020)
10.21468/SciPostPhysCore.2.1.002
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Since the incident nuclei in heavy-ion collisions do not carry strangeness, the global net strangeness of the detected hadrons has to vanish. We investigate the impact of strangeness neutrality on the phase structure and thermodynamics of QCD at finite baryon and strangeness chemical potential. To this end, we study the low-energy sector of QCD within a Polyakov loop enhanced quark-meson effective theory with 2+1 dynamical quark flavors. Non-perturbative quantum, thermal, and density fluctuations are taken into account with the functional renormalization group. We show that the impact of strangeness neutrality on thermodynamic quantities such as the equation of state is sizable.
[ { "created": "Wed, 1 Aug 2018 16:44:56 GMT", "version": "v1" }, { "created": "Tue, 26 Nov 2019 23:57:07 GMT", "version": "v2" } ]
2020-04-03
[ [ "Fu", "Wei-jie", "" ], [ "Pawlowski", "Jan M.", "" ], [ "Rennecke", "Fabian", "" ] ]
Since the incident nuclei in heavy-ion collisions do not carry strangeness, the global net strangeness of the detected hadrons has to vanish. We investigate the impact of strangeness neutrality on the phase structure and thermodynamics of QCD at finite baryon and strangeness chemical potential. To this end, we study the low-energy sector of QCD within a Polyakov loop enhanced quark-meson effective theory with 2+1 dynamical quark flavors. Non-perturbative quantum, thermal, and density fluctuations are taken into account with the functional renormalization group. We show that the impact of strangeness neutrality on thermodynamic quantities such as the equation of state is sizable.
2404.09006
Tetsuo Nishikawa
Tetsuo Nishikawa, Yoshihiko Kondo, Yoshiko Kanada-En'yo
QCD sum rules for positive and negative parity heavy baryons at next-to-leading order in $\alpha_s$-expansion
16 pages, 19 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
QCD sum rules for positive and negative parity heavy baryons in the heavy quark limit are formulated. We apply the method to $\Lambda$ and $\Sigma$ channels. We include the next-to-leading order corrections in $\alpha_s$-expansion to dimension 0 and 3 terms in the operator product expansion. The corrections lead to the considerable reduction of the predicted masses and significantly improves the stability with respect to the Borel parameter, especially for negative parity states. It is also found that in the heavy quark limit chiral odd condensates do not contribute to the negative parity states.
[ { "created": "Sat, 13 Apr 2024 13:22:59 GMT", "version": "v1" } ]
2024-04-16
[ [ "Nishikawa", "Tetsuo", "" ], [ "Kondo", "Yoshihiko", "" ], [ "Kanada-En'yo", "Yoshiko", "" ] ]
QCD sum rules for positive and negative parity heavy baryons in the heavy quark limit are formulated. We apply the method to $\Lambda$ and $\Sigma$ channels. We include the next-to-leading order corrections in $\alpha_s$-expansion to dimension 0 and 3 terms in the operator product expansion. The corrections lead to the considerable reduction of the predicted masses and significantly improves the stability with respect to the Borel parameter, especially for negative parity states. It is also found that in the heavy quark limit chiral odd condensates do not contribute to the negative parity states.
hep-ph/9805378
Wim deBoer
W. de Boer, H.J. Grimm, A.V. Gladyshev, D.I. Kazakov
Higgs Limit and b->s gamma Constraints in Minimal Supersymmetry
latex + 6 eps figs, 10 pages, IEKP-KA/98-08; References updated in replacement + 1 figure concerning triple Yukawa unification added for final publication in Phys. Lett
Phys.Lett. B438 (1998) 281-289
10.1016/S0370-2693(98)00986-1
null
hep-ph
null
New limits on the Higgs mass from LEP and new calculations on the radiative (penguin) decay of the b->s gamma branching ratio restrict the parameter space of the Constrained Minimal Supersymmetric Standard Model (CMSSM). We find that for the low tan(beta) scenario only one sign of the Higgs mixing parameter is allowed, while the high tan(beta scenario is practically excluded, if one requires all sparticles to be below 1 TeV and imposes radiative electroweak symmetry breaking as well as gauge and Yukawa coupling unification. For squarks between 1 and 2 TeV high tan(beta) scenarios are allowed. We consider especially a new high tan(beta)=64 scenario with triple unification of all Yukawa couplings of the third generation, which show an infrared fixed point behaviour. The upper limit on the mass of the lightest Higgs in the low (high) tan(beta) scenarios is 97+-6~(120+-2) GeV, where the errors originate predominantly from the uncertainty in the top mass.
[ { "created": "Tue, 19 May 1998 16:01:14 GMT", "version": "v1" }, { "created": "Sat, 23 May 1998 20:22:32 GMT", "version": "v2" }, { "created": "Fri, 24 Jul 1998 17:46:46 GMT", "version": "v3" } ]
2009-10-31
[ [ "de Boer", "W.", "" ], [ "Grimm", "H. J.", "" ], [ "Gladyshev", "A. V.", "" ], [ "Kazakov", "D. I.", "" ] ]
New limits on the Higgs mass from LEP and new calculations on the radiative (penguin) decay of the b->s gamma branching ratio restrict the parameter space of the Constrained Minimal Supersymmetric Standard Model (CMSSM). We find that for the low tan(beta) scenario only one sign of the Higgs mixing parameter is allowed, while the high tan(beta scenario is practically excluded, if one requires all sparticles to be below 1 TeV and imposes radiative electroweak symmetry breaking as well as gauge and Yukawa coupling unification. For squarks between 1 and 2 TeV high tan(beta) scenarios are allowed. We consider especially a new high tan(beta)=64 scenario with triple unification of all Yukawa couplings of the third generation, which show an infrared fixed point behaviour. The upper limit on the mass of the lightest Higgs in the low (high) tan(beta) scenarios is 97+-6~(120+-2) GeV, where the errors originate predominantly from the uncertainty in the top mass.
1709.07091
Ken'ichi Saikawa
Ken'ichi Saikawa
Axion as a non-WIMP dark matter candidate
6 pages, 2 figures, contribution to the proceedings of the European Physical Society Conference on High Energy Physics, 5-12 July 2017, Venice, Italy; v2: typos corrected, accepted for publication
PoS (EPS-HEP2017) 083
null
DESY 17-141
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The axion arises in well-motivated extensions of the Standard Model of particle physics and is regarded as an alternative to the weakly interacting massive particle paradigm to explain the nature of dark matter. In this contribution, we review theoretical aspects of dark matter axions, particularly focusing on recent developments in the estimation of their relic abundance. A closer look at their non-thermal production mechanisms in the early universe reveals the possibility of explaining the observed dark matter abundance in various mass ranges. The mass ranges predicted in various cosmological scenarios are briefly summarized.
[ { "created": "Wed, 20 Sep 2017 21:44:02 GMT", "version": "v1" }, { "created": "Mon, 29 Jan 2018 13:06:54 GMT", "version": "v2" } ]
2018-01-30
[ [ "Saikawa", "Ken'ichi", "" ] ]
The axion arises in well-motivated extensions of the Standard Model of particle physics and is regarded as an alternative to the weakly interacting massive particle paradigm to explain the nature of dark matter. In this contribution, we review theoretical aspects of dark matter axions, particularly focusing on recent developments in the estimation of their relic abundance. A closer look at their non-thermal production mechanisms in the early universe reveals the possibility of explaining the observed dark matter abundance in various mass ranges. The mass ranges predicted in various cosmological scenarios are briefly summarized.
1305.6779
Jean Iliopoulos
Jean Iliopoulos (LPTENS)
Introduction to the STANDARD MODEL of the Electro-Weak Interactions
null
2012 CERN Summer School of Particle Physics, Angers : France (2012)
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
These are the notes of a set of four lectures which I gave at the 2012 CERN Summer School of Particle Physics. They cover the basic ideas of gauge symmetries and the phenomenon of spontaneous symmetry breaking which are used in the construction of the Standard Model of the Electro-Weak Interactions.
[ { "created": "Wed, 29 May 2013 12:41:59 GMT", "version": "v1" } ]
2013-05-30
[ [ "Iliopoulos", "Jean", "", "LPTENS" ] ]
These are the notes of a set of four lectures which I gave at the 2012 CERN Summer School of Particle Physics. They cover the basic ideas of gauge symmetries and the phenomenon of spontaneous symmetry breaking which are used in the construction of the Standard Model of the Electro-Weak Interactions.
1312.2072
Sun Kesheng
Ke-Sheng Sun, Tai-Fu Feng, Li-Na Kou, Fei Sun, Tie-Jun Gao, Hai-Bin Zhang
Lepton flavor violation decays of vector mesons in unparticle physics
10 pages, 3 figures
MPLA:Vol. 27, No. 30 (2012) 1250172
10.1142/S0217732312501726
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the lepton flavor violation decays of vector mesons in the scenario of the unparticle physics by considering the constraint from $\mu-e$ conversion. In unparticle physics, the predictions of LFV decays of vector mesons depend strongly on the scale dimension $d_{\mathcal{U}}$. The predictions of LFV decays of vector mesons can reach the detective sensitivity in experiment in region of $3\le d_{\mathcal{U}}\le 4$, while the prediction of $\mu-e$ conversion rate can meet the experimental upper limit. For the searching of the lepton flavor violation processes of charged lepton sector in experiment, the process $\Upsilon\rightarrow e\mu$ may be a promising one to be observed.
[ { "created": "Sat, 7 Dec 2013 08:18:51 GMT", "version": "v1" } ]
2013-12-10
[ [ "Sun", "Ke-Sheng", "" ], [ "Feng", "Tai-Fu", "" ], [ "Kou", "Li-Na", "" ], [ "Sun", "Fei", "" ], [ "Gao", "Tie-Jun", "" ], [ "Zhang", "Hai-Bin", "" ] ]
We investigate the lepton flavor violation decays of vector mesons in the scenario of the unparticle physics by considering the constraint from $\mu-e$ conversion. In unparticle physics, the predictions of LFV decays of vector mesons depend strongly on the scale dimension $d_{\mathcal{U}}$. The predictions of LFV decays of vector mesons can reach the detective sensitivity in experiment in region of $3\le d_{\mathcal{U}}\le 4$, while the prediction of $\mu-e$ conversion rate can meet the experimental upper limit. For the searching of the lepton flavor violation processes of charged lepton sector in experiment, the process $\Upsilon\rightarrow e\mu$ may be a promising one to be observed.
hep-ph/9701370
Nobuchika Okada
Noriaki Kitazawa and Nobuchika Okada
A Supersymmetric Composite Model with Dynamical Supersymmetry Breaking
30 pages, uses REVTEX macro, revised manuscript to appear in Phys. Rev. D
Phys.Rev. D56 (1997) 2842-2851
10.1103/PhysRevD.56.2842
TMUP-HEL-9701
hep-ph
null
We present a supersymmetric composite model with dynamical supersymmetry breaking. The model is based on the gauge group $SU(2)_S \times SU(2)_H \times SU(3)_c \times SU(2)_L \times U(1)_Y$. Supersymmetry is dynamically broken by the non-perturbative effect of the $SU(2)_S$ `supercolor' interaction. The large top Yukawa coupling is naturally generated by the $SU(2)_H$ `hypercolor' interaction as recently proposed by Nelson and Strassler. The supersymmetry breaking is mediated to the standard model sector by a new mechanism. The electroweak symmetry breaking is caused by the radiative correction due to the large top Yukawa coupling with the supersymmetry breaking. This is the `radiative breaking scenario', which originates from the dynamics of the supercolor and hypercolor gauge interactions.
[ { "created": "Fri, 24 Jan 1997 14:06:17 GMT", "version": "v1" }, { "created": "Sat, 14 Jun 1997 11:06:30 GMT", "version": "v2" } ]
2009-10-30
[ [ "Kitazawa", "Noriaki", "" ], [ "Okada", "Nobuchika", "" ] ]
We present a supersymmetric composite model with dynamical supersymmetry breaking. The model is based on the gauge group $SU(2)_S \times SU(2)_H \times SU(3)_c \times SU(2)_L \times U(1)_Y$. Supersymmetry is dynamically broken by the non-perturbative effect of the $SU(2)_S$ `supercolor' interaction. The large top Yukawa coupling is naturally generated by the $SU(2)_H$ `hypercolor' interaction as recently proposed by Nelson and Strassler. The supersymmetry breaking is mediated to the standard model sector by a new mechanism. The electroweak symmetry breaking is caused by the radiative correction due to the large top Yukawa coupling with the supersymmetry breaking. This is the `radiative breaking scenario', which originates from the dynamics of the supercolor and hypercolor gauge interactions.
hep-ph/0702197
Emidio Gabrielli
Emidio Gabrielli and Massimo Giovannini
Testing PVLAS axions with resonant photon splitting
7 pages, 2 included eps figures, two references added, minor typos corrected
null
null
CERN-PH-TH/2007-033, HIP-2007-04/TH
hep-ph astro-ph
null
The photon splitting gamma -> gamma gamma in a time-independent and inhomogeneous magnetized background is considered when neutral and ultralight spin-0 particles are coupled to two-photons. Depending on the inhomogeneity scale of the external field, resonant photon splitting can occur. If an optical laser crosses a magnetic field of few Tesla with typical inhomogeneity scale of the order of the meter, a potentially observable rate of photon splittings is expected for the PVLAS range of couplings and masses.
[ { "created": "Mon, 19 Feb 2007 21:55:09 GMT", "version": "v1" }, { "created": "Mon, 26 Feb 2007 19:16:57 GMT", "version": "v2" } ]
2007-05-23
[ [ "Gabrielli", "Emidio", "" ], [ "Giovannini", "Massimo", "" ] ]
The photon splitting gamma -> gamma gamma in a time-independent and inhomogeneous magnetized background is considered when neutral and ultralight spin-0 particles are coupled to two-photons. Depending on the inhomogeneity scale of the external field, resonant photon splitting can occur. If an optical laser crosses a magnetic field of few Tesla with typical inhomogeneity scale of the order of the meter, a potentially observable rate of photon splittings is expected for the PVLAS range of couplings and masses.
1205.4325
Qin Chang
Qin Chang, Xiao-Wei Cui, Lin Han and Ya-Dong Yang
Revisiting the Annihilation Corrections in Non-leptonic $\bar{B}_s^0$ Decays within QCD Factorization
25pages, 6 figures; minor typos corrected; version to appear in Phys. Rev. D
null
10.1103/PhysRevD.86.054016
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the recent measurements of non-leptonic $\bar{B}_s^0$ decays by CDF and LHCb collaborations, especially the large ${\cal B}(\bar{B}_s^0\to\pi^+\pi^-)$, we revisit the hard spectator and annihilation corrections in $\bar{B}_s^0$ decays within QCD factorization approach with two schemes for the possible parameters for the known end-point divergence appeared in the estimation of the hard spectator and annihilation diagrams. The first one is to conservatively estimate the possible contributions by parameterization (scheme I); another one uses an infrared finite gluon propagator (scheme II) to regulate the end-point singularity. In scheme I, with the constraints from the measured $\bar{B}_s^0\to PP (VV)$ decays, two (four) restricted solutions of the parameters spaces are found. In scheme II, we find that most of the theoretical predictions agree well with the experimental data with single parameter $m_{g}\sim 0.5{\rm GeV}$. However, within both schemes, ${\cal B}(\bar{B}_s^0\to\phi\phi)$ are always much larger than ${\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$ in contrast to the experimental results ${\cal B}(\bar{B}_s^0\to\phi\phi)\simeq{\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$. It is noted that the pattern ${\cal B}(\bar{B}_s^0\to\phi\phi)>{\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$ also persists in other theoretical framework, thus the present experimental result ${\cal B}(\bar{B}_s^0\to\phi\phi) \simeq {\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$ rises a challenge to theoretical approaches for B non-leptonic decays. Further refined measurements and theoretical studies are called for to resolve such a possible anomaly.
[ { "created": "Sat, 19 May 2012 13:16:42 GMT", "version": "v1" }, { "created": "Tue, 9 Oct 2012 08:44:13 GMT", "version": "v2" } ]
2012-10-10
[ [ "Chang", "Qin", "" ], [ "Cui", "Xiao-Wei", "" ], [ "Han", "Lin", "" ], [ "Yang", "Ya-Dong", "" ] ]
Motivated by the recent measurements of non-leptonic $\bar{B}_s^0$ decays by CDF and LHCb collaborations, especially the large ${\cal B}(\bar{B}_s^0\to\pi^+\pi^-)$, we revisit the hard spectator and annihilation corrections in $\bar{B}_s^0$ decays within QCD factorization approach with two schemes for the possible parameters for the known end-point divergence appeared in the estimation of the hard spectator and annihilation diagrams. The first one is to conservatively estimate the possible contributions by parameterization (scheme I); another one uses an infrared finite gluon propagator (scheme II) to regulate the end-point singularity. In scheme I, with the constraints from the measured $\bar{B}_s^0\to PP (VV)$ decays, two (four) restricted solutions of the parameters spaces are found. In scheme II, we find that most of the theoretical predictions agree well with the experimental data with single parameter $m_{g}\sim 0.5{\rm GeV}$. However, within both schemes, ${\cal B}(\bar{B}_s^0\to\phi\phi)$ are always much larger than ${\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$ in contrast to the experimental results ${\cal B}(\bar{B}_s^0\to\phi\phi)\simeq{\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$. It is noted that the pattern ${\cal B}(\bar{B}_s^0\to\phi\phi)>{\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$ also persists in other theoretical framework, thus the present experimental result ${\cal B}(\bar{B}_s^0\to\phi\phi) \simeq {\cal B}(\bar{B}_s^0\to K^{\ast 0}\bar{K}^{\ast 0})$ rises a challenge to theoretical approaches for B non-leptonic decays. Further refined measurements and theoretical studies are called for to resolve such a possible anomaly.
1411.5658
P. S. Bhupal Dev
Chien-Yi Chen, P. S. Bhupal Dev, Amarjit Soni
A Possible Two-component Flux for the High Energy Neutrino Events at IceCube
10 pages, 5 figures, 1 table; expanded discussion on the two-component solution and added Figure 4; version to appear in Phys. Rev. D
Phys. Rev. D 92, 073001 (2015)
10.1103/PhysRevD.92.073001
MAN/HEP/2014/14
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding the spectral and flavor composition of the astrophysical neutrino flux responsible for the recently observed ultra-high energy events at IceCube is of great importance for both astrophysics and particle physics. We perform a statistical likelihood analysis to the 3-year IceCube data and derive the allowed range of the spectral index and flux normalization for various well-motivated physical flavor compositions at source. While most of the existing analyses so far assume the flavor composition of the neutrinos at an astrophysical source to be (1:2:0), it seems rather unnatural to assume only one type of source, once we recognize the possibility of at least two physical sources. Bearing this in mind, we entertain the possibility of a two-component source for the analysis of IceCube data. It appears that our two component hypothesis explains some key features of the data better than a single-component scenario, i.e it addresses the apparent energy gap between 400 TeV to about 1 PeV and easily accommodates the observed track to shower ratio. Given the extreme importance of the flavor composition for the correct interpretation of the underlying astrophysical processes as well as for the ramification for particle physics, this two-component flux should be tested as more data is accumulated.
[ { "created": "Thu, 20 Nov 2014 19:59:58 GMT", "version": "v1" }, { "created": "Tue, 2 Dec 2014 19:37:14 GMT", "version": "v2" }, { "created": "Tue, 2 Jun 2015 17:23:12 GMT", "version": "v3" }, { "created": "Wed, 9 Sep 2015 05:38:01 GMT", "version": "v4" } ]
2015-10-05
[ [ "Chen", "Chien-Yi", "" ], [ "Dev", "P. S. Bhupal", "" ], [ "Soni", "Amarjit", "" ] ]
Understanding the spectral and flavor composition of the astrophysical neutrino flux responsible for the recently observed ultra-high energy events at IceCube is of great importance for both astrophysics and particle physics. We perform a statistical likelihood analysis to the 3-year IceCube data and derive the allowed range of the spectral index and flux normalization for various well-motivated physical flavor compositions at source. While most of the existing analyses so far assume the flavor composition of the neutrinos at an astrophysical source to be (1:2:0), it seems rather unnatural to assume only one type of source, once we recognize the possibility of at least two physical sources. Bearing this in mind, we entertain the possibility of a two-component source for the analysis of IceCube data. It appears that our two component hypothesis explains some key features of the data better than a single-component scenario, i.e it addresses the apparent energy gap between 400 TeV to about 1 PeV and easily accommodates the observed track to shower ratio. Given the extreme importance of the flavor composition for the correct interpretation of the underlying astrophysical processes as well as for the ramification for particle physics, this two-component flux should be tested as more data is accumulated.
hep-ph/9403262
null
S.V.Faleev, P.G.Silvestrov
Instanton -- Antiinstanton interaction and asymptotics of perturbation theory expansion in double well oscillator
12 pages, Latex, BUDKERINP 94-24
Phys.Lett. A197 (1995) 372
10.1016/0375-9601(94)00965-R
null
hep-ph hep-th
null
Instanton -- antiinstanton pair is considered as a source of singularity at the Borel plane for the ground state energy of anharmonic oscillator. The problem of defining the short range instanton -- antiinstanton interaction reduces to calculation of a smooth part of the Borel function, which cannot be found without explicit calculation of several terms of ordinary perturbation theory. On the other hand, the large order terms of perturbative expansion are dominated by large fluctuations in the functional integral like well separated instanton and antiinstanton. The preasymptotics ($\sim 1/n$) of large order perturbation theory contribution to the ground state energy of anharmonic oscillator was found analytically. To this end the subleading long range asymptotics of the classical instanton -- antiinstanton interaction, the one -- loop quantum contribution to instanton -- antiinstanton interaction and the second quantum correction to a single instanton density were considered.
[ { "created": "Thu, 10 Mar 1994 11:36:43 GMT", "version": "v1" } ]
2009-10-28
[ [ "Faleev", "S. V.", "" ], [ "Silvestrov", "P. G.", "" ] ]
Instanton -- antiinstanton pair is considered as a source of singularity at the Borel plane for the ground state energy of anharmonic oscillator. The problem of defining the short range instanton -- antiinstanton interaction reduces to calculation of a smooth part of the Borel function, which cannot be found without explicit calculation of several terms of ordinary perturbation theory. On the other hand, the large order terms of perturbative expansion are dominated by large fluctuations in the functional integral like well separated instanton and antiinstanton. The preasymptotics ($\sim 1/n$) of large order perturbation theory contribution to the ground state energy of anharmonic oscillator was found analytically. To this end the subleading long range asymptotics of the classical instanton -- antiinstanton interaction, the one -- loop quantum contribution to instanton -- antiinstanton interaction and the second quantum correction to a single instanton density were considered.
2306.13009
Maxim Perelstein
Steven Ferrante, Seung J. Lee, Maxim Perelstein
Collider Signatures of Near-Continuum Dark Matter
27 pages, 12 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this paper we study a near-continuum dark matter model, in which dark sector consists of a tower of closely spaced states with weak-scale masses. We construct a five-dimensional model which naturally realizes this spectrum. The dark matter is described by a bulk field, which interacts with the brane-localized Standard Model sector via a Z portal. We then study collider signatures of this model. Near-continuum dark matter states produced in a collider undergo cascade decays, resulting in events with high multiplicity of jets and leptons, large missing energy, and displaced vertices. A custom-built Monte Carlo tool described in this paper allows for detailed simulation of the signal events. We present results of such simulations for the case of electron-positron collisions.
[ { "created": "Thu, 22 Jun 2023 16:17:28 GMT", "version": "v1" } ]
2023-06-23
[ [ "Ferrante", "Steven", "" ], [ "Lee", "Seung J.", "" ], [ "Perelstein", "Maxim", "" ] ]
In this paper we study a near-continuum dark matter model, in which dark sector consists of a tower of closely spaced states with weak-scale masses. We construct a five-dimensional model which naturally realizes this spectrum. The dark matter is described by a bulk field, which interacts with the brane-localized Standard Model sector via a Z portal. We then study collider signatures of this model. Near-continuum dark matter states produced in a collider undergo cascade decays, resulting in events with high multiplicity of jets and leptons, large missing energy, and displaced vertices. A custom-built Monte Carlo tool described in this paper allows for detailed simulation of the signal events. We present results of such simulations for the case of electron-positron collisions.
2003.04039
Timon Emken
Riccardo Catena and Timon Emken and Julia Ravanis
Rejecting the Majorana nature of dark matter with electron scattering experiments
15 pages + appendix, 5 figures. Code available at https://github.com/temken/Dirac_vs_Majorana and https://doi.org/10.5281/zenodo.3701262 . Comments welcome! v2: matches published version
JCAP06(2020)056
10.1088/1475-7516/2020/06/056
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Assuming that Dark Matter (DM) is made of fermions in the sub-GeV mass range with interactions dominated by electromagnetic moments of higher order, such as the electric and magnetic dipoles or the anapole moment, we show that direct detection experiments searching for atomic ionisation events in xenon targets can shed light on whether DM is a Dirac or Majorana particle. Specifically, we find that between about 45 (120) and 610 (1700) signal events are required to reject Majorana DM in favour of Dirac DM with a statistical significance corresponding to 3 (5) standard deviations. The exact number of DM signal events corresponding to a given significance depends on the relative size of the anapole, magnetic dipole and electric dipole contributions to the expected rate of DM-induced atomic ionisations under the Dirac hypothesis. Our conclusions are based on Monte Carlo simulations and the likelihood ratio test. While the use of asymptotic formulae for the latter is standard in many applications, here it requires a non-trivial extension to the case where one of the hypotheses lies on the boundary of the parameter space. Our results constitute a solid proof of concept about the possibility of using direct detection experiments to reject the Majorana DM hypothesis when the DM interactions are dominated by higher-order electromagnetic moments.
[ { "created": "Mon, 9 Mar 2020 11:06:25 GMT", "version": "v1" }, { "created": "Wed, 8 Jul 2020 09:42:57 GMT", "version": "v2" } ]
2020-07-09
[ [ "Catena", "Riccardo", "" ], [ "Emken", "Timon", "" ], [ "Ravanis", "Julia", "" ] ]
Assuming that Dark Matter (DM) is made of fermions in the sub-GeV mass range with interactions dominated by electromagnetic moments of higher order, such as the electric and magnetic dipoles or the anapole moment, we show that direct detection experiments searching for atomic ionisation events in xenon targets can shed light on whether DM is a Dirac or Majorana particle. Specifically, we find that between about 45 (120) and 610 (1700) signal events are required to reject Majorana DM in favour of Dirac DM with a statistical significance corresponding to 3 (5) standard deviations. The exact number of DM signal events corresponding to a given significance depends on the relative size of the anapole, magnetic dipole and electric dipole contributions to the expected rate of DM-induced atomic ionisations under the Dirac hypothesis. Our conclusions are based on Monte Carlo simulations and the likelihood ratio test. While the use of asymptotic formulae for the latter is standard in many applications, here it requires a non-trivial extension to the case where one of the hypotheses lies on the boundary of the parameter space. Our results constitute a solid proof of concept about the possibility of using direct detection experiments to reject the Majorana DM hypothesis when the DM interactions are dominated by higher-order electromagnetic moments.
1611.03409
Giovanni Marco Pruna Dr
A. Crivellin, S. Davidson, G. M. Pruna and A. Signer
Complementarity in lepton-flavour violating muon decay experiments
8 pages, 1 figure
null
null
NUFACT2016-Pruna, PSI-PR-16-15
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This note presents an analysis of lepton-flavour-violating muon decays within the framework of a low-energy effective field theory that contains higher-dimensional operators allowed by QED and QCD symmetries. The decay modes $\mu\to e \gamma$ and $\mu\to 3e$ are investigated below the electroweak symmetry-breaking scale, down to energies at which such processes occur, i.e. the muon mass scale. The complete class of dimension-5 and dimension-6 operators is studied systematically at the tree level, and one-loop contributions to the renormalisation group equations are fully taken into account. Current experimental limits are used to extract bounds on the Wilson coefficients of some of the operators and, ultimately, on the effective couplings at any energy level below the electroweak symmetry-breaking scale. Correlations between two couplings relevant to both processes illustrate the complementarity of searches planned for the MEG II and Mu3e experiments.
[ { "created": "Thu, 10 Nov 2016 17:29:15 GMT", "version": "v1" } ]
2017-05-24
[ [ "Crivellin", "A.", "" ], [ "Davidson", "S.", "" ], [ "Pruna", "G. M.", "" ], [ "Signer", "A.", "" ] ]
This note presents an analysis of lepton-flavour-violating muon decays within the framework of a low-energy effective field theory that contains higher-dimensional operators allowed by QED and QCD symmetries. The decay modes $\mu\to e \gamma$ and $\mu\to 3e$ are investigated below the electroweak symmetry-breaking scale, down to energies at which such processes occur, i.e. the muon mass scale. The complete class of dimension-5 and dimension-6 operators is studied systematically at the tree level, and one-loop contributions to the renormalisation group equations are fully taken into account. Current experimental limits are used to extract bounds on the Wilson coefficients of some of the operators and, ultimately, on the effective couplings at any energy level below the electroweak symmetry-breaking scale. Correlations between two couplings relevant to both processes illustrate the complementarity of searches planned for the MEG II and Mu3e experiments.
1211.4581
Mart\'in Gonz\'alez-Alonso
Mart\'in Gonz\'alez-Alonso, Michael J. Ramsey-Musolf
Leptophobic Z' Boson and Parity-Violating eD Scattering
6 pages, 5 figures
null
10.1103/PhysRevD.87.055013
NPAC-12-18
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the impact of a leptophobic Z' gauge boson on the C_{1q} and C_{2q} parameters that describe the low-energy, parity-violating electron-quark neutral current interaction. We complement previous work by including the penguin-like vertex corrections, thereby completing the analysis of one-loop calculation up to O(m^2_q'/M^2_Z') terms. We analyze the sensitivity of these probes to the different couplings Z'\bar{u}q (q=u,c,t) and Z'\bar{d}q (q=d,s,b), in a model-independent way that can be applied to any specific Z' scenario. We show that constraints from neutral kaon and heavy flavor studies preclude significant contributions from flavor non-diagonal couplings except for those involving top quarks. We apply our results to a light Z' with flavor diagonal couplings to up or down quarks, a scenario proposed in the literature to explained the CDF W plus di-jet anomaly. We find that such a particle would not affect the C_{1q} coefficients, but it would have a sizable impact on C_{2q} couplings that can be probed by future measurements of parity-violating deep inelastic scattering of polarized electrons off of deuterium.
[ { "created": "Mon, 19 Nov 2012 21:00:04 GMT", "version": "v1" } ]
2013-03-27
[ [ "González-Alonso", "Martín", "" ], [ "Ramsey-Musolf", "Michael J.", "" ] ]
We study the impact of a leptophobic Z' gauge boson on the C_{1q} and C_{2q} parameters that describe the low-energy, parity-violating electron-quark neutral current interaction. We complement previous work by including the penguin-like vertex corrections, thereby completing the analysis of one-loop calculation up to O(m^2_q'/M^2_Z') terms. We analyze the sensitivity of these probes to the different couplings Z'\bar{u}q (q=u,c,t) and Z'\bar{d}q (q=d,s,b), in a model-independent way that can be applied to any specific Z' scenario. We show that constraints from neutral kaon and heavy flavor studies preclude significant contributions from flavor non-diagonal couplings except for those involving top quarks. We apply our results to a light Z' with flavor diagonal couplings to up or down quarks, a scenario proposed in the literature to explained the CDF W plus di-jet anomaly. We find that such a particle would not affect the C_{1q} coefficients, but it would have a sizable impact on C_{2q} couplings that can be probed by future measurements of parity-violating deep inelastic scattering of polarized electrons off of deuterium.
1210.5523
David Curtin
David Curtin, Rouven Essig, Brian Shuve
Boosted Multijet Resonances and New Color-Flow Variables
21 pages, 13 figures, 3 tables. Added MC comparison for QCD background in Appendix
null
10.1103/PhysRevD.88.034019
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use modern jet-substructure techniques to propose LHC searches for multijet-resonance signals without leptons or missing energy. We focus on three-jet resonances produced by R-parity-violating decays of boosted gluinos, showing that shape analyses searching for a mass peak can probe such gluinos up to masses of ~ 750 GeV (650 GeV) with 20/fb (5/fb) at the LHC at 8 TeV. This complements existing search strategies, which also include counting methods that are inherently more prone to systematic uncertainties. Since R-parity-violating gluinos lighter than all squarks hadronize before decaying, we introduce new color-flow variables, "radial pull" and "axis contraction", which are sensitive to the color structure of the R-hadron's decay. The former measures the inward pull of subjets in a fat jet, while the latter quantifies the inward drift of the $N$-subjettiness axes when changing the distance measure. We show that they can dramatically improve the discrimination of a boosted gluino signal versus QCD, ttbar and combinatoric background for m_gluino ~ m_top. Cuts on axis contraction also noticeably improve the resonance shape for heavy gluinos with m_gluino > ~500 GeV. With minor adaptations, these variables could find application in substructure searches for particles in different color representations or with other decay topologies. We also compare how several different Monte Carlo generators model the high-multiplicity QCD background. This provides evidence that the discriminating power of our color-flow observables are robust, and provides useful guidance for future substructure studies.
[ { "created": "Fri, 19 Oct 2012 20:00:02 GMT", "version": "v1" }, { "created": "Fri, 27 Sep 2013 18:33:52 GMT", "version": "v2" } ]
2013-09-30
[ [ "Curtin", "David", "" ], [ "Essig", "Rouven", "" ], [ "Shuve", "Brian", "" ] ]
We use modern jet-substructure techniques to propose LHC searches for multijet-resonance signals without leptons or missing energy. We focus on three-jet resonances produced by R-parity-violating decays of boosted gluinos, showing that shape analyses searching for a mass peak can probe such gluinos up to masses of ~ 750 GeV (650 GeV) with 20/fb (5/fb) at the LHC at 8 TeV. This complements existing search strategies, which also include counting methods that are inherently more prone to systematic uncertainties. Since R-parity-violating gluinos lighter than all squarks hadronize before decaying, we introduce new color-flow variables, "radial pull" and "axis contraction", which are sensitive to the color structure of the R-hadron's decay. The former measures the inward pull of subjets in a fat jet, while the latter quantifies the inward drift of the $N$-subjettiness axes when changing the distance measure. We show that they can dramatically improve the discrimination of a boosted gluino signal versus QCD, ttbar and combinatoric background for m_gluino ~ m_top. Cuts on axis contraction also noticeably improve the resonance shape for heavy gluinos with m_gluino > ~500 GeV. With minor adaptations, these variables could find application in substructure searches for particles in different color representations or with other decay topologies. We also compare how several different Monte Carlo generators model the high-multiplicity QCD background. This provides evidence that the discriminating power of our color-flow observables are robust, and provides useful guidance for future substructure studies.
hep-ph/0409088
Frank J. Petriello
Charalampos Anastasiou, Kirill Melnikov, Frank Petriello
Higgs boson production at hadron colliders: differential cross sections through next-to-next-to-leading order
4 pgs, 2 figs; references added
Phys.Rev.Lett.93:262002,2004
10.1103/PhysRevLett.93.262002
null
hep-ph hep-ex
null
We present a calculation of the fully differential cross section for Higgs boson production in the gluon fusion channel through next-to-next-to-leading order in perturbative QCD. We apply the method introduced in \cite{Anastasiou:2003gr} to compute double real emission corrections. Our calculation permits arbitrary cuts on the final state in the reaction $hh \to H + X$. It can be easily extended to include decays of the Higgs boson into observable final states. In this Letter, we discuss the most important features of the calculation, and present some examples of physical applications that illustrate the range of observables that can be studied using our result. We compute the NNLO rapidity distribution of the Higgs boson, and also calculate the NNLO rapidity distribution with a veto on jet activity.
[ { "created": "Wed, 8 Sep 2004 13:15:45 GMT", "version": "v1" }, { "created": "Tue, 28 Sep 2004 14:17:16 GMT", "version": "v2" } ]
2010-04-06
[ [ "Anastasiou", "Charalampos", "" ], [ "Melnikov", "Kirill", "" ], [ "Petriello", "Frank", "" ] ]
We present a calculation of the fully differential cross section for Higgs boson production in the gluon fusion channel through next-to-next-to-leading order in perturbative QCD. We apply the method introduced in \cite{Anastasiou:2003gr} to compute double real emission corrections. Our calculation permits arbitrary cuts on the final state in the reaction $hh \to H + X$. It can be easily extended to include decays of the Higgs boson into observable final states. In this Letter, we discuss the most important features of the calculation, and present some examples of physical applications that illustrate the range of observables that can be studied using our result. We compute the NNLO rapidity distribution of the Higgs boson, and also calculate the NNLO rapidity distribution with a veto on jet activity.
hep-ph/9512244
masanori Miyama
S. Kumano (Saga Univ./ECT*) and M. Miyama (Saga Univ.)
Nuclear dependence of Q^2 evolution in the structure function F_2
10 pages, Latex, 2 eps figures. Complete postscript file including the figures is available at ftp://ftp.cc.saga-u.ac.jp/pub/paper/riko/quantum1/saga-he-83.ps.gz or at http://www.cc.saga-u.ac.jp/saga-u/riko/physics/quantum1/structure.html
Phys.Lett.B378:267-271,1996
10.1016/0370-2693(96)00429-7
SAGA-HE-83-95, ECT*/NOV 95/03
hep-ph nucl-th
null
$Q^2$ evolution of the structure functions $F_2$ in tin and carbon nuclei is investigated in order to understand recent NMC measurements. $F_2$ is evolved by using leading-order DGLAP, next-to-leading-order DGLAP, and parton-recombination equations. NMC experimental result $\partial [F_2^{Sn}/F_2^C]/ \partial [\ln Q^2]\ne 0$ could be essentially understood by the difference of parton distributions in the tin and carbon nuclei. However, we find an interesting indication that large higher-twist effects on the $Q^2$ evolution could be ruled out. Nuclear dependence of the $Q^2$ evolution could be interesting for further detailed studies. 1. Introduction 2. Q^2 evolution of F_2 in tin and carbon nuclei 3. Conclusions
[ { "created": "Wed, 6 Dec 1995 08:22:08 GMT", "version": "v1" } ]
2014-11-17
[ [ "Kumano", "S.", "", "Saga Univ./ECT*" ], [ "Miyama", "M.", "", "Saga Univ." ] ]
$Q^2$ evolution of the structure functions $F_2$ in tin and carbon nuclei is investigated in order to understand recent NMC measurements. $F_2$ is evolved by using leading-order DGLAP, next-to-leading-order DGLAP, and parton-recombination equations. NMC experimental result $\partial [F_2^{Sn}/F_2^C]/ \partial [\ln Q^2]\ne 0$ could be essentially understood by the difference of parton distributions in the tin and carbon nuclei. However, we find an interesting indication that large higher-twist effects on the $Q^2$ evolution could be ruled out. Nuclear dependence of the $Q^2$ evolution could be interesting for further detailed studies. 1. Introduction 2. Q^2 evolution of F_2 in tin and carbon nuclei 3. Conclusions
1010.4808
Alexander Kobushkin
Dmitry Borisyuk, Alexander Kobushkin
Two-photon exchange in elastic electron-pion scattering
5 pages, 3 figures. Minor text changes, Eq.(3) corrected, to appear in Phys.Rev.C
Phys.Rev.C83:025203,2011
10.1103/PhysRevC.83.025203
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate two-photon exchange amplitude for the elastic electron-pion scattering in the dispersion-relation inspired approach, including both elastic and inelastic contributions. The latter was modelled as a sum of \rho and b_1(1235) meson contributions. We find that at Q^2 < 2 GeV^2 the elastic contribution is dominant, similarly to electron-proton scattering case. At higher Q^2 the inelastic contribution is not negligible, but still smaller than the elastic one. We also explain observed rapid amplitude growth at backward angles.
[ { "created": "Fri, 22 Oct 2010 20:24:27 GMT", "version": "v1" }, { "created": "Fri, 21 Jan 2011 14:32:25 GMT", "version": "v2" } ]
2015-03-17
[ [ "Borisyuk", "Dmitry", "" ], [ "Kobushkin", "Alexander", "" ] ]
We calculate two-photon exchange amplitude for the elastic electron-pion scattering in the dispersion-relation inspired approach, including both elastic and inelastic contributions. The latter was modelled as a sum of \rho and b_1(1235) meson contributions. We find that at Q^2 < 2 GeV^2 the elastic contribution is dominant, similarly to electron-proton scattering case. At higher Q^2 the inelastic contribution is not negligible, but still smaller than the elastic one. We also explain observed rapid amplitude growth at backward angles.
1508.05940
Suchita Kulkarni Ms.
Frank F. Deppisch, Lukas Graf, Suchita Kulkarni, Sudhanwa Patra, Werner Rodejohann, Narendra Sahu, Utpal Sarkar
Reconciling the 2 TeV Excesses at the LHC in a Linear Seesaw Left-Right Model
References added, typos fixed, matches published version, 12 pages, 4 figures
Phys. Rev. D 93, 013011 (2016)
10.1103/PhysRevD.93.013011
HEPHY-PUB 958/15
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We interpret the 2 TeV excesses at the LHC in a left-right symmetric model with Higgs doublets and spontaneous $D$-parity violation. The light neutrino masses are understood via a linear seesaw, suppressed by a high $D$-parity breaking scale, and the heavy neutrinos have a pseudo-Dirac character. In addition, with a suppressed right-handed gauge coupling $g_R / g_L \approx 0.6$ in an $SO(10)$ embedding, we can thereby interpret the observed $eejj$ excess at CMS. We show that it can be reconciled with the diboson and dijet excesses within a simplified scenario based on our model. Moreover, we find that the mixing between the light and heavy neutrinos can be potentially large which would induce dominant non-standard contributions to neutrinoless double beta decay via long-range $\lambda$ and $\eta$ neutrino exchange.
[ { "created": "Mon, 24 Aug 2015 20:04:38 GMT", "version": "v1" }, { "created": "Thu, 14 Jan 2016 21:55:35 GMT", "version": "v2" } ]
2016-01-20
[ [ "Deppisch", "Frank F.", "" ], [ "Graf", "Lukas", "" ], [ "Kulkarni", "Suchita", "" ], [ "Patra", "Sudhanwa", "" ], [ "Rodejohann", "Werner", "" ], [ "Sahu", "Narendra", "" ], [ "Sarkar", "Utpal", "" ] ]
We interpret the 2 TeV excesses at the LHC in a left-right symmetric model with Higgs doublets and spontaneous $D$-parity violation. The light neutrino masses are understood via a linear seesaw, suppressed by a high $D$-parity breaking scale, and the heavy neutrinos have a pseudo-Dirac character. In addition, with a suppressed right-handed gauge coupling $g_R / g_L \approx 0.6$ in an $SO(10)$ embedding, we can thereby interpret the observed $eejj$ excess at CMS. We show that it can be reconciled with the diboson and dijet excesses within a simplified scenario based on our model. Moreover, we find that the mixing between the light and heavy neutrinos can be potentially large which would induce dominant non-standard contributions to neutrinoless double beta decay via long-range $\lambda$ and $\eta$ neutrino exchange.
hep-ph/0503088
Rohini Godbole Professor
Rohini M. Godbole
CP violation in Supesymmetry and the LHC
12 pages, 8 figures, LaTeX, requires cjpsuppl.cls, Talk presented at 'Physics at LHC', Vienna, 13-17 July, 2004. References added. Minor corrections in the text and references
Czech.J.Phys. 55 (2005) B221-B231
null
IISc-CHEP/19/05
hep-ph
null
In this talk I discuss possibilities of probing the CP violation (CPV) in the Minimal Supersymmetric Standard Model (MSSM), at the LHC as well as its effects on the LHC SUSY phenomenology. In the latter case I mainly discuss its effect on the Higgs-sector and hence on Higgs Phenomenology at the LHC. After outlining the possibilities that a study of the $\ch_1 \nt_2$ production at the LHC might offer, I will summarise the effects of the CPV in MSSM on the Higgs searches at the LHC. Further, I will discuss how a study of the process $H^\pm \to W^+ \phi_1$ may be able to plug a 'hole" in the $\tan \beta$-$\mh{+}$ plane, where the LEP has no sensitivity and where the searches in the usual discovery channels at the LHC are likely to fail as well.
[ { "created": "Wed, 9 Mar 2005 09:27:46 GMT", "version": "v1" }, { "created": "Wed, 16 Mar 2005 09:04:13 GMT", "version": "v2" } ]
2007-05-23
[ [ "Godbole", "Rohini M.", "" ] ]
In this talk I discuss possibilities of probing the CP violation (CPV) in the Minimal Supersymmetric Standard Model (MSSM), at the LHC as well as its effects on the LHC SUSY phenomenology. In the latter case I mainly discuss its effect on the Higgs-sector and hence on Higgs Phenomenology at the LHC. After outlining the possibilities that a study of the $\ch_1 \nt_2$ production at the LHC might offer, I will summarise the effects of the CPV in MSSM on the Higgs searches at the LHC. Further, I will discuss how a study of the process $H^\pm \to W^+ \phi_1$ may be able to plug a 'hole" in the $\tan \beta$-$\mh{+}$ plane, where the LEP has no sensitivity and where the searches in the usual discovery channels at the LHC are likely to fail as well.
1509.04671
Rishi Sharma
Rajiv Gavai, Ambar Jain, Rishi Sharma
Unravelling Medium Effects in Heavy Ion Collisions with Zeal
5 pages, 7 figures
null
null
TIFR/TH/15-26
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new observable, called zeal, to analyze events with jets in heavy ion collisions. The observable measures how a thermal medium affects the multiplicity and distribution of energetic particles in a jet. Using few known models for energy loss and jet quenching, we demonstrate its capability to distinguish the physics of these models.
[ { "created": "Tue, 15 Sep 2015 18:29:06 GMT", "version": "v1" } ]
2015-09-21
[ [ "Gavai", "Rajiv", "" ], [ "Jain", "Ambar", "" ], [ "Sharma", "Rishi", "" ] ]
We propose a new observable, called zeal, to analyze events with jets in heavy ion collisions. The observable measures how a thermal medium affects the multiplicity and distribution of energetic particles in a jet. Using few known models for energy loss and jet quenching, we demonstrate its capability to distinguish the physics of these models.
hep-ph/9509388
Josephine Bolosan
S.F. Tuan (University of Hawaii)
Aspects of Charmonium
7 pages, LATEX format
null
null
UH 511-832-95
hep-ph
null
Here we discuss three separate topics in charmonium physics. (1) The Omicron \OMC as $1^{--}$ trigluonia, and the charmonium puzzle; the $\eta_c' (3600)$ search. (2) The decay $\psi(^1P_1) \to \pi^o + J/\psi$ and isospin violating charmonium decays. (3) How to search for $\chi_c' = \chi_c(2P)$ charmonium states.
[ { "created": "Tue, 26 Sep 1995 02:17:29 GMT", "version": "v1" } ]
2007-05-23
[ [ "Tuan", "S. F.", "", "University of Hawaii" ] ]
Here we discuss three separate topics in charmonium physics. (1) The Omicron \OMC as $1^{--}$ trigluonia, and the charmonium puzzle; the $\eta_c' (3600)$ search. (2) The decay $\psi(^1P_1) \to \pi^o + J/\psi$ and isospin violating charmonium decays. (3) How to search for $\chi_c' = \chi_c(2P)$ charmonium states.
0810.5239
Werner Rodejohann
Werner Rodejohann
Unified Parametrization for Quark and Lepton Mixing Angles
10 pages. Comments and references added, to appear in PLB
Phys.Lett.B671:267-271,2009
10.1016/j.physletb.2008.12.010
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new parametrization for the quark and lepton mixing matrices: the two 12-mixing angles (the Cabibbo angle and the angle responsible for solar neutrino oscillations) are at zeroth order pi/12 and pi/5, respectively. The resulting 12-elements in the CKM and PMNS matrices, V_{us} and U_{e2}, are in this order irrational but simple algebraic numbers. We note that the cosine of pi/5 is the golden ratio divided by two. The difference between pi/5 and the observed best-fit value of solar neutrino mixing is of the same order as the difference between the observed value and the one for tri-bimaximal mixing. In order to reproduce the central values of current fits, corrections to the zeroth order expressions are necessary. They are small and of the same order and sign for quarks and leptons. We parametrize the perturbations to the CKM and PMNS matrices in a 'triminimal' way, i.e., with three small rotations in an order corresponding to the order of the rotations in the PDG-description of mixing matrices.
[ { "created": "Wed, 29 Oct 2008 10:45:01 GMT", "version": "v1" }, { "created": "Tue, 9 Dec 2008 09:50:30 GMT", "version": "v2" } ]
2010-04-21
[ [ "Rodejohann", "Werner", "" ] ]
We propose a new parametrization for the quark and lepton mixing matrices: the two 12-mixing angles (the Cabibbo angle and the angle responsible for solar neutrino oscillations) are at zeroth order pi/12 and pi/5, respectively. The resulting 12-elements in the CKM and PMNS matrices, V_{us} and U_{e2}, are in this order irrational but simple algebraic numbers. We note that the cosine of pi/5 is the golden ratio divided by two. The difference between pi/5 and the observed best-fit value of solar neutrino mixing is of the same order as the difference between the observed value and the one for tri-bimaximal mixing. In order to reproduce the central values of current fits, corrections to the zeroth order expressions are necessary. They are small and of the same order and sign for quarks and leptons. We parametrize the perturbations to the CKM and PMNS matrices in a 'triminimal' way, i.e., with three small rotations in an order corresponding to the order of the rotations in the PDG-description of mixing matrices.
2208.01097
Da Huang
Da Huang, Chao-Qiang Geng, Jiajun Wu
Unitarity Bounds on the Massive Spin-2 Particle Explanation of Muon $g-2$ Anomaly
23 pages, 7 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Motivated by the long-standing discrepancy between the Standard Model prediction and the experimental measurement of the muon magnetic dipole moment, we have recently proposed to interpret this muon $g-2$ anomaly in terms of the loop effect induced by a new massive spin-2 field $G$. In the present paper, we investigate the unitarity bounds on this scenario. We calculate the $s$-wave projected amplitudes for two-body elastic scatterings of charged leptons and photons mediated by $G$ at high energies for all possible initial and final helicity states. By imposing the condition of the perturbative unitarity, we obtain the analytic constraints on the charged-lepton-$G$ and photon-$G$ couplings. We then apply our results to constrain the parameter space relevant to the explanation of the muon $g-2$ anomaly.
[ { "created": "Mon, 1 Aug 2022 18:55:19 GMT", "version": "v1" } ]
2022-08-03
[ [ "Huang", "Da", "" ], [ "Geng", "Chao-Qiang", "" ], [ "Wu", "Jiajun", "" ] ]
Motivated by the long-standing discrepancy between the Standard Model prediction and the experimental measurement of the muon magnetic dipole moment, we have recently proposed to interpret this muon $g-2$ anomaly in terms of the loop effect induced by a new massive spin-2 field $G$. In the present paper, we investigate the unitarity bounds on this scenario. We calculate the $s$-wave projected amplitudes for two-body elastic scatterings of charged leptons and photons mediated by $G$ at high energies for all possible initial and final helicity states. By imposing the condition of the perturbative unitarity, we obtain the analytic constraints on the charged-lepton-$G$ and photon-$G$ couplings. We then apply our results to constrain the parameter space relevant to the explanation of the muon $g-2$ anomaly.
0709.3174
Carlos Merino
G. H. Arakelyan, C. Merino, C. Pajares and Yu. M. Shabelski
Midrapidity Production of Secondaries in pp Collisions at RHIC and LHC Energies in the Quark-Gluon String Model
12 pages, 5 figures, and 1 table
Eur.Phys.J.C54:577-581,2008
10.1140/epjc/s10052-008-0554-1
null
hep-ph
null
We consider the phenomenological implications of the assumption that baryons are systems of three quarks connected through gluon string junction. The transfer of baryon number in rapidity space due to the string junction propagation is considered in detail. At high energies this process leads to a significant effect on the net baryon production in hN collisions at mid-rapidities. The numerical results for midrapidity inclusive densities of different secondaries in the framework of the Quark-Gluon String Model are in reasonable agreement with the experimental data. One universal value lambda ~ 0.25 for the strangeness suppression parameter correctly describes the yield ratios of Lambda/p, Xi/Lambda, and Omega/Xi. The predictions for pp collisions at LHC energies are also presented.
[ { "created": "Thu, 20 Sep 2007 10:25:04 GMT", "version": "v1" } ]
2008-11-26
[ [ "Arakelyan", "G. H.", "" ], [ "Merino", "C.", "" ], [ "Pajares", "C.", "" ], [ "Shabelski", "Yu. M.", "" ] ]
We consider the phenomenological implications of the assumption that baryons are systems of three quarks connected through gluon string junction. The transfer of baryon number in rapidity space due to the string junction propagation is considered in detail. At high energies this process leads to a significant effect on the net baryon production in hN collisions at mid-rapidities. The numerical results for midrapidity inclusive densities of different secondaries in the framework of the Quark-Gluon String Model are in reasonable agreement with the experimental data. One universal value lambda ~ 0.25 for the strangeness suppression parameter correctly describes the yield ratios of Lambda/p, Xi/Lambda, and Omega/Xi. The predictions for pp collisions at LHC energies are also presented.
hep-ph/0602118
Giorgio Torrieri
Giorgio Torrieri, Charles Gale, Sangyong Jeon, Vasile Topor Pop
Fluctuations in jet momentum as an energy loss probe
null
null
null
null
hep-ph hep-ex nucl-ex nucl-th
null
We investigate the measurement of the distribution of away-side jet $p_T$ as a way to probe the energy loss mechanism in heavy ion collisions, and constrain the properties of the medium created in heavy ion collisions. We define an observable related to the fluctuation of the energy deposited in the medium, and show that competing models of parton energy loss give differing values and scaling of this observable. We also argue that the scaling of this observable with system size can be related to the medium's partonic density. We then give a qualitative discussion of how the measurement we suggest can be performed and used to determine the parton energy loss mechanism and possibly the system's partonic density.
[ { "created": "Tue, 14 Feb 2006 00:19:36 GMT", "version": "v1" } ]
2007-05-23
[ [ "Torrieri", "Giorgio", "" ], [ "Gale", "Charles", "" ], [ "Jeon", "Sangyong", "" ], [ "Pop", "Vasile Topor", "" ] ]
We investigate the measurement of the distribution of away-side jet $p_T$ as a way to probe the energy loss mechanism in heavy ion collisions, and constrain the properties of the medium created in heavy ion collisions. We define an observable related to the fluctuation of the energy deposited in the medium, and show that competing models of parton energy loss give differing values and scaling of this observable. We also argue that the scaling of this observable with system size can be related to the medium's partonic density. We then give a qualitative discussion of how the measurement we suggest can be performed and used to determine the parton energy loss mechanism and possibly the system's partonic density.
1008.4498
Gennaro Corcella
Gennaro Corcella
Theoretical issues on the top mass reconstruction at hadron colliders
8 pages, 4 figures, 3 tables. Talk given at TOP 2010, 3rd International Workshop on Top Quark Physics, May 31 - June 4, Bruges, Belgium
null
10.1393/ncc/i2010-10671-4
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I discuss a few selected topics related to the reconstruction of the mass of the top quark at hadron colliders. In particular, the relation between the measured top mass and theoretical definitions, such as the pole or MSbar mass, is debated. I will also summarize recent studies on the Monte Carlo uncertainty due to the fragmentation of bottom quarks in top decays.
[ { "created": "Thu, 26 Aug 2010 13:03:32 GMT", "version": "v1" }, { "created": "Mon, 13 Sep 2010 13:19:49 GMT", "version": "v2" } ]
2022-03-02
[ [ "Corcella", "Gennaro", "" ] ]
I discuss a few selected topics related to the reconstruction of the mass of the top quark at hadron colliders. In particular, the relation between the measured top mass and theoretical definitions, such as the pole or MSbar mass, is debated. I will also summarize recent studies on the Monte Carlo uncertainty due to the fragmentation of bottom quarks in top decays.
hep-ph/0209113
Krzysztof Urbanowski
K. Urbanowski
Studying the Bell--Steinberger relation
LaTex2e, 17 pages, some typos corrected and references added
Eur.Phys.J. C37 (2004) 233-240
10.1140/epjc/s2004-01992-0
null
hep-ph hep-ex hep-th
null
The Bell--Steinberger relation is analyzed. The questionable points of the standard derivation of this relation are discussed. It is shown that the use of a more accurate approximation than the one usually used in the derivation of this relation can lead to corrections to the right hand side of the standard Bell--Steinberger relation.
[ { "created": "Wed, 11 Sep 2002 09:30:00 GMT", "version": "v1" }, { "created": "Mon, 10 Feb 2003 08:07:55 GMT", "version": "v2" } ]
2016-02-17
[ [ "Urbanowski", "K.", "" ] ]
The Bell--Steinberger relation is analyzed. The questionable points of the standard derivation of this relation are discussed. It is shown that the use of a more accurate approximation than the one usually used in the derivation of this relation can lead to corrections to the right hand side of the standard Bell--Steinberger relation.
hep-ph/0006280
Guo Hong Wu
Ken Kiers, Amarjit Soni, Guo-Hong Wu
Direct CP violation in radiative b decays in and beyond the Standard Model
RevTex, 24 pages, 6 figures, minor changes, version to appear in PRD
Phys.Rev.D62:116004,2000
10.1103/PhysRevD.62.116004
null
hep-ph hep-ex
null
We consider the partial rate asymmetry in the inclusive decay modes b to s gamma and b to d gamma, concentrating on non-standard models with new charged Higgs interactions. We find that the charged Higgs contribution to the asymmetry for b to s gamma is small in such models due to a universal cancellation mechanism. The asymmetry is therefore difficult to distinguish experimentally from the Standard Model (SM) value, which is also small. The cancellation mechanism is found to be rendered inoperative in supersymmetry due to the presence of chargino loops. Unlike b to s gamma, the rate asymmetry for b to d gamma in Higgs models can be quite different from its SM value, generally ranging from -20% to +20%. Specific model calculations are performed for the Three-Higgs Doublet Model and the ``Top'' Two-Higgs Doublet Model to serve as illustrations. We also offer some suggestions that may be helpful to experimentalists in the detection of the inclusive mode b to d gamma.
[ { "created": "Sat, 24 Jun 2000 03:06:09 GMT", "version": "v1" }, { "created": "Wed, 25 Oct 2000 23:55:28 GMT", "version": "v2" } ]
2014-11-17
[ [ "Kiers", "Ken", "" ], [ "Soni", "Amarjit", "" ], [ "Wu", "Guo-Hong", "" ] ]
We consider the partial rate asymmetry in the inclusive decay modes b to s gamma and b to d gamma, concentrating on non-standard models with new charged Higgs interactions. We find that the charged Higgs contribution to the asymmetry for b to s gamma is small in such models due to a universal cancellation mechanism. The asymmetry is therefore difficult to distinguish experimentally from the Standard Model (SM) value, which is also small. The cancellation mechanism is found to be rendered inoperative in supersymmetry due to the presence of chargino loops. Unlike b to s gamma, the rate asymmetry for b to d gamma in Higgs models can be quite different from its SM value, generally ranging from -20% to +20%. Specific model calculations are performed for the Three-Higgs Doublet Model and the ``Top'' Two-Higgs Doublet Model to serve as illustrations. We also offer some suggestions that may be helpful to experimentalists in the detection of the inclusive mode b to d gamma.
hep-ph/9507268
null
Reginald T. Cahill and Susan M. Gunner
A New Mass Formula for NG Bosons in QCD
Minor correction. Extended text incl. appendix
Mod.Phys.Lett. A10 (1995) 3051
10.1142/S0217732395003185
null
hep-ph nucl-th
null
An often used mass formula for Nambu-Goldstone (NG) bosons in QCD, such as the pions, involves the condensate $<\overline{q}q>$, $f_{\pi}$ and the quark current masses. We argue, within the context of the Global Colour Model to QCD, that this expression is wrong. Analysis of the interplay between the Dyson-Schwinger equation for the constituent quark effect and the Bethe-Salpeter equation for the NG boson results in a new mass formula.
[ { "created": "Mon, 10 Jul 1995 02:37:12 GMT", "version": "v1" }, { "created": "Wed, 30 Aug 1995 06:28:53 GMT", "version": "v2" }, { "created": "Fri, 1 Sep 1995 01:23:06 GMT", "version": "v3" } ]
2009-10-28
[ [ "Cahill", "Reginald T.", "" ], [ "Gunner", "Susan M.", "" ] ]
An often used mass formula for Nambu-Goldstone (NG) bosons in QCD, such as the pions, involves the condensate $<\overline{q}q>$, $f_{\pi}$ and the quark current masses. We argue, within the context of the Global Colour Model to QCD, that this expression is wrong. Analysis of the interplay between the Dyson-Schwinger equation for the constituent quark effect and the Bethe-Salpeter equation for the NG boson results in a new mass formula.
1411.2554
Alexander Nesterenko
A.V. Nesterenko
Hadronic vacuum polarization function within dispersive approach to QCD
16 pages, 4 figures
J. Phys. G: Nucl. Part. Phys. 42, 085004 (2015)
10.1088/0954-3899/42/8/085004
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The dispersive approach to quantum chromodynamics is applied to the study of the hadronic vacuum polarization function and associated quantities. This approach merges the intrinsically nonperturbative constraints, which originate in the kinematic restrictions on the respective physical processes, with corresponding perturbative input. The obtained hadronic vacuum polarization function agrees with pertinent lattice simulation data. The evaluated hadronic contributions to the muon anomalous magnetic moment and to the shift of the electromagnetic fine structure constant conform with recent assessments of these quantities.
[ { "created": "Mon, 10 Nov 2014 19:43:26 GMT", "version": "v1" }, { "created": "Thu, 19 Feb 2015 16:48:48 GMT", "version": "v2" }, { "created": "Mon, 29 Jun 2015 09:26:31 GMT", "version": "v3" } ]
2015-07-14
[ [ "Nesterenko", "A. V.", "" ] ]
The dispersive approach to quantum chromodynamics is applied to the study of the hadronic vacuum polarization function and associated quantities. This approach merges the intrinsically nonperturbative constraints, which originate in the kinematic restrictions on the respective physical processes, with corresponding perturbative input. The obtained hadronic vacuum polarization function agrees with pertinent lattice simulation data. The evaluated hadronic contributions to the muon anomalous magnetic moment and to the shift of the electromagnetic fine structure constant conform with recent assessments of these quantities.
1407.3167
Mortaza Khatiri Yanehsari
M. Ghasemkhani, R. Goldouzian, H. Khanpour, M. Khatiri, M. Mohammadi
Higgs production in $e^{-}e^{+}$ collisions as a probe of noncommutativity
6 figures, 2 tables
Prog. Theor. Exp. Phys. 2014, 081B01
10.1093/ptep/ptu110
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the sensitivity of the angular distribution of the Higgs boson in the process of $e^+e^-\to Z H$ and the total cross section in the minimal noncommutative standard model (mNCSM) framework to set lower limit on the noncommutative charactristic scale ($\Lambda$). Contrary to the standard model case, in this process the Higgs boson tends to be emitted anisotropically in the transverse plane. Based on this fact, the profile likelihood ratio is used to set lower limit on $\Lambda$. The lower limit is presented as a function of the integrated luminosity. We show that at the center-of-mass energy of 1.5 TeV and with 500 fb$^{-1}$ of data, the noncommutative characteristic energy scale $\Lambda$ can be excluded up to 1.2 TeV.
[ { "created": "Fri, 11 Jul 2014 14:12:02 GMT", "version": "v1" }, { "created": "Mon, 14 Jul 2014 13:00:25 GMT", "version": "v2" } ]
2014-08-15
[ [ "Ghasemkhani", "M.", "" ], [ "Goldouzian", "R.", "" ], [ "Khanpour", "H.", "" ], [ "Khatiri", "M.", "" ], [ "Mohammadi", "M.", "" ] ]
We examine the sensitivity of the angular distribution of the Higgs boson in the process of $e^+e^-\to Z H$ and the total cross section in the minimal noncommutative standard model (mNCSM) framework to set lower limit on the noncommutative charactristic scale ($\Lambda$). Contrary to the standard model case, in this process the Higgs boson tends to be emitted anisotropically in the transverse plane. Based on this fact, the profile likelihood ratio is used to set lower limit on $\Lambda$. The lower limit is presented as a function of the integrated luminosity. We show that at the center-of-mass energy of 1.5 TeV and with 500 fb$^{-1}$ of data, the noncommutative characteristic energy scale $\Lambda$ can be excluded up to 1.2 TeV.
hep-ph/0310327
Peter Kroll
P. Kroll (Universitaet Wuppertal)
The handbag mechanism in wide-angle exclusive reactions
12 pages, 10 figures (using LATEX with ws-procs9x6.cls) invited talk presented at NAPP2003, Dubrownik, May, 2003
Fizika B13 (2004) 153-162
null
null
hep-ph
null
The handbag mechanism for wide-angle exclusive scattering reactions is discussed and compared with other theoretical approaches. Its application to Compton scattering, meson photoproduction and two-photon annihilations into pairs of hadrons is reviewed in some detail.
[ { "created": "Wed, 29 Oct 2003 12:04:16 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kroll", "P.", "", "Universitaet Wuppertal" ] ]
The handbag mechanism for wide-angle exclusive scattering reactions is discussed and compared with other theoretical approaches. Its application to Compton scattering, meson photoproduction and two-photon annihilations into pairs of hadrons is reviewed in some detail.
hep-ph/0110121
Gino Isidori
Gino Isidori and Alessandra Retico
Scalar flavour-changing neutral currents in the large-tan(beta) limit
22 pages, Latex, 6 figures; v3: minor misprints corrected with respect to the published version
JHEP 0111:001,2001
10.1088/1126-6708/2001/11/001
CERN-TH/2001-266
hep-ph
null
We analyse scalar flavour-changing neutral currents of down-type quarks in models with two Higgs doublets, coupled separately to up- and down-type quarks, in the limit where the ratio of the two expectation values ($\tan \beta = v_u/v_d$) is large. We clarify the origin of this phenomenon, both in $\Delta F=1$ and $\Delta F=2$ processes, analysing differences and analogies between supersymmetric and non-supersymmetric models. We confirm previous findings of a sizeable enhancement at large $\tan\beta$ of specific $\Delta F=1$ and $\Delta F=2$ amplitudes in the MSSM and, in these cases, we discuss how large-$\tan\beta$ corrections can be controlled beyond lowest order. Finally, we emphasize the unique role of the rare processes $B_{s,d} \to \tau^+ \tau^-$ and $B_{s,d} \to \mu^+ \mu^-$ in probing this scenario.
[ { "created": "Tue, 9 Oct 2001 12:01:07 GMT", "version": "v1" }, { "created": "Tue, 20 Nov 2001 09:07:51 GMT", "version": "v2" }, { "created": "Mon, 1 Jul 2002 17:07:47 GMT", "version": "v3" } ]
2010-02-03
[ [ "Isidori", "Gino", "" ], [ "Retico", "Alessandra", "" ] ]
We analyse scalar flavour-changing neutral currents of down-type quarks in models with two Higgs doublets, coupled separately to up- and down-type quarks, in the limit where the ratio of the two expectation values ($\tan \beta = v_u/v_d$) is large. We clarify the origin of this phenomenon, both in $\Delta F=1$ and $\Delta F=2$ processes, analysing differences and analogies between supersymmetric and non-supersymmetric models. We confirm previous findings of a sizeable enhancement at large $\tan\beta$ of specific $\Delta F=1$ and $\Delta F=2$ amplitudes in the MSSM and, in these cases, we discuss how large-$\tan\beta$ corrections can be controlled beyond lowest order. Finally, we emphasize the unique role of the rare processes $B_{s,d} \to \tau^+ \tau^-$ and $B_{s,d} \to \mu^+ \mu^-$ in probing this scenario.
hep-ph/0405195
Roelof Bijker
R. Bijker (ICN-UNAM, Mexico), M.M. Giannini and E. Santopinto (Genova, Italy)
Pentaquark spectroscopy: exotic Theta baryons
6 pages, 2 figures, invited talk at Nuclear Physics, Large and Small, April 19-22, 2004, Hacienda Cocoyoc, Mexico, to be published in AIP Conference Proceedings. Reference added
AIP CP 726, 181 (2004)
10.1063/1.1805936
null
hep-ph
null
We propose a collective stringlike model of pentaquarks with the geometry of an equilateral tetrahedron in which the four quarks are located at the four corners and the antiquark in its center. The nonplanar equilibrium configuration is a consequence of the permutation symmetry of the four quarks. In an application to the spectrum of exotic Theta baryons, we find that the ground state pentaquark has angular momentum and parity J(p)=1/2(-) and a small magnetic moment of 0.382 nuclear magnetons. The decay width is suppressed by the spatial overlap with the decay products.
[ { "created": "Thu, 20 May 2004 16:03:27 GMT", "version": "v1" }, { "created": "Tue, 25 May 2004 18:39:18 GMT", "version": "v2" } ]
2017-11-02
[ [ "Bijker", "R.", "", "ICN-UNAM, Mexico" ], [ "Giannini", "M. M.", "", "Genova,\n Italy" ], [ "Santopinto", "E.", "", "Genova,\n Italy" ] ]
We propose a collective stringlike model of pentaquarks with the geometry of an equilateral tetrahedron in which the four quarks are located at the four corners and the antiquark in its center. The nonplanar equilibrium configuration is a consequence of the permutation symmetry of the four quarks. In an application to the spectrum of exotic Theta baryons, we find that the ground state pentaquark has angular momentum and parity J(p)=1/2(-) and a small magnetic moment of 0.382 nuclear magnetons. The decay width is suppressed by the spatial overlap with the decay products.
1006.0432
Michele Papucci
Zoltan Ligeti, Michele Papucci, Gilad Perez and Jure Zupan
Implications of the dimuon CP asymmetry in B_{d,s} decays
5 pages, 4 figures; final version accepted in PRL
Phys.Rev.Lett.105:131601,2010
10.1103/PhysRevLett.105.131601
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The D0 Collaboration reported a 3.2sigma deviation from the standard model prediction in the like-sign dimuon asymmetry. Assuming that new physics contributes only to B_{d,s} mixing, we show that the data can be analyzed without using the theoretical calculation of \Delta\Gamma_s, allowing for robust interpretations. We find that this framework gives a good fit to all measurements, including the recent CDF S_{\psi\phi} result. The data allow universal new physics with similar contributions relative to the SM in the B_d and B_s systems, but favors a larger deviation in B_s than in B_d mixing. The general minimal flavor violation framework with flavor diagonal CP violating phases can account for the former and remarkably even for the latter case. This observation makes it simpler to speculate about which extensions with general flavor structure may also fit the data.
[ { "created": "Wed, 2 Jun 2010 16:03:46 GMT", "version": "v1" }, { "created": "Thu, 16 Sep 2010 19:19:55 GMT", "version": "v2" } ]
2014-11-21
[ [ "Ligeti", "Zoltan", "" ], [ "Papucci", "Michele", "" ], [ "Perez", "Gilad", "" ], [ "Zupan", "Jure", "" ] ]
The D0 Collaboration reported a 3.2sigma deviation from the standard model prediction in the like-sign dimuon asymmetry. Assuming that new physics contributes only to B_{d,s} mixing, we show that the data can be analyzed without using the theoretical calculation of \Delta\Gamma_s, allowing for robust interpretations. We find that this framework gives a good fit to all measurements, including the recent CDF S_{\psi\phi} result. The data allow universal new physics with similar contributions relative to the SM in the B_d and B_s systems, but favors a larger deviation in B_s than in B_d mixing. The general minimal flavor violation framework with flavor diagonal CP violating phases can account for the former and remarkably even for the latter case. This observation makes it simpler to speculate about which extensions with general flavor structure may also fit the data.
1307.6142
Roberto Pittau
Ben Page and Roberto Pittau
R2 vertices for the effective ggH theory
7 pages, 1 figure
null
10.1007/JHEP09(2013)078
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We list all possible R2 Feynman rules needed in NLO computations involving couplings of Higgs and gluons mediated by an infinitely heavy top loop. They provide the rational contribution generated by the (d-4)-dimensional part of the amplitude, paving the way for four-dimensional automatic NLO methods in Higgs phenomenology.
[ { "created": "Tue, 23 Jul 2013 16:27:00 GMT", "version": "v1" } ]
2015-06-16
[ [ "Page", "Ben", "" ], [ "Pittau", "Roberto", "" ] ]
We list all possible R2 Feynman rules needed in NLO computations involving couplings of Higgs and gluons mediated by an infinitely heavy top loop. They provide the rational contribution generated by the (d-4)-dimensional part of the amplitude, paving the way for four-dimensional automatic NLO methods in Higgs phenomenology.
1105.1290
Jens O. Andersen
Jens O. Andersen and Rashid Khan
Chiral transition in a magnetic field and at finite baryon density
11 pages. 5figs. V2: fixed a few typos and added refs. Submitted to PRD. V3: Added refs and substantial revision of text
null
10.1103/PhysRevD.85.065026
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the quark-meson model with two quark flavors in a constant external magnetic field $B$ at finite temperature $T$ and finite baryon chemical potential $\mu_B$. We calculate the full renormalized effective potential to one-loop order in perturbation theory. We study the system in the large-$N_c$ limit, where we treat the bosonic modes at tree level. It is shown that the system exhibits dynamical chiral symmetry breaking, i. e. that an arbitrarily weak magnetic field breaks chiral symmetry dynamically, in agreement with earlier calculations using the NJL model. We study the influence on the phase transition of the fermionic vacuum fluctuations. For strong magnetic fields, $|qB|\sim5m_{\pi}^2$ and in the chiral limit, the transition is first order in the entire $\mu_B-T$ plane if vacuum fluctuations are not included and second order if they are included. At the physical point, the transition is a crossover for $\mu_B=0$ with and without vacuum fluctuations.
[ { "created": "Fri, 6 May 2011 14:17:06 GMT", "version": "v1" }, { "created": "Thu, 21 Jul 2011 10:11:01 GMT", "version": "v2" }, { "created": "Mon, 12 Dec 2011 11:20:00 GMT", "version": "v3" } ]
2015-05-28
[ [ "Andersen", "Jens O.", "" ], [ "Khan", "Rashid", "" ] ]
We consider the quark-meson model with two quark flavors in a constant external magnetic field $B$ at finite temperature $T$ and finite baryon chemical potential $\mu_B$. We calculate the full renormalized effective potential to one-loop order in perturbation theory. We study the system in the large-$N_c$ limit, where we treat the bosonic modes at tree level. It is shown that the system exhibits dynamical chiral symmetry breaking, i. e. that an arbitrarily weak magnetic field breaks chiral symmetry dynamically, in agreement with earlier calculations using the NJL model. We study the influence on the phase transition of the fermionic vacuum fluctuations. For strong magnetic fields, $|qB|\sim5m_{\pi}^2$ and in the chiral limit, the transition is first order in the entire $\mu_B-T$ plane if vacuum fluctuations are not included and second order if they are included. At the physical point, the transition is a crossover for $\mu_B=0$ with and without vacuum fluctuations.
hep-ph/0407342
Stefano Scopel
N. Fornengo (1,2), L. Pieri (1), S. Scopel (1) ((1) Torino University, (2) INFN, Sezione di Torino)
Neutralino annihilation into gamma-rays in the Milky Way and in external galaxies
17 pages, 9 tables and 14 figures, typeset with ReVTeX4. A Figure and a comment on the recent HESS data have been added. The version on the archive has low-resolution figures. The paper with high resolution figures may be found through http://www.astroparticle.to.infn.it
Phys.Rev.D70:103529,2004
10.1103/PhysRevD.70.103529
DFTT 17/2004
hep-ph astro-ph
null
We discuss the gamma-ray signal from dark matter annihilation in our Galaxy and in external objects, namely the Large Magellanic Cloud, the Andromeda Galaxy (M31) and M87. We derive predictions for the fluxes in a low energy realization of the Minimal Supersymmetric Standard Model and compare them with current data from EGRET, CANGAROO-II and HEGRA and with the capabilities of new-generation satellite-borne experiments, like GLAST, and ground-based Cerenkov telescopes, like VERITAS. We find fluxes below the level required to explain the possible indications of a gamma-ray excess shown by CANGAROO-II (toward the Galactic Center) and HEGRA (from M87). As far as future experiments are concerned, we show that only the signal from the galactic center could be accessible to both satellite-borne experiments and to ACTs, even though this requires very steep dark matter density profiles.
[ { "created": "Thu, 29 Jul 2004 15:57:51 GMT", "version": "v1" }, { "created": "Wed, 4 Aug 2004 15:47:26 GMT", "version": "v2" }, { "created": "Thu, 26 Aug 2004 12:15:23 GMT", "version": "v3" }, { "created": "Mon, 30 Aug 2004 07:22:39 GMT", "version": "v4" } ]
2008-11-26
[ [ "Fornengo", "N.", "" ], [ "Pieri", "L.", "" ], [ "Scopel", "S.", "" ] ]
We discuss the gamma-ray signal from dark matter annihilation in our Galaxy and in external objects, namely the Large Magellanic Cloud, the Andromeda Galaxy (M31) and M87. We derive predictions for the fluxes in a low energy realization of the Minimal Supersymmetric Standard Model and compare them with current data from EGRET, CANGAROO-II and HEGRA and with the capabilities of new-generation satellite-borne experiments, like GLAST, and ground-based Cerenkov telescopes, like VERITAS. We find fluxes below the level required to explain the possible indications of a gamma-ray excess shown by CANGAROO-II (toward the Galactic Center) and HEGRA (from M87). As far as future experiments are concerned, we show that only the signal from the galactic center could be accessible to both satellite-borne experiments and to ACTs, even though this requires very steep dark matter density profiles.
2204.13316
Kan Chen
Kan Chen, Bo-Lin Huang, Bo Wang, and Shi-Lin Zhu
$\Sigma_c\Sigma_c$ interactions in chiral effective field theory
12 pages, 11 figure
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We study the interactions of the $\Sigma_c\Sigma_c$ system in the framework of chiral effective theory. We consider the contact, one-pion and two-pion exchange interactions and bridge the low energy constants of the $\Sigma_c\Sigma_c$ system to those of the $\Sigma_c^{(*)}\bar{D}^{(*)}$ systems through the quark-level ansatz for the contact interaction. We explore the influence of intermediate channels in the two-pion exchange diagrams of the $\Sigma_c\Sigma_c$ system. We obtain a deep bound state $[\Sigma_c\Sigma_c]_{J=0}^{I=0}$ and a shallow bound state $[\Sigma_c\Sigma_c]_{J=1}^{I=1}$. As a byproduct, we further investigate the interactions of the $\Lambda_c\Lambda_c$ and $\Lambda_c\Sigma_c$ systems.
[ { "created": "Thu, 28 Apr 2022 07:30:44 GMT", "version": "v1" } ]
2022-04-29
[ [ "Chen", "Kan", "" ], [ "Huang", "Bo-Lin", "" ], [ "Wang", "Bo", "" ], [ "Zhu", "Shi-Lin", "" ] ]
We study the interactions of the $\Sigma_c\Sigma_c$ system in the framework of chiral effective theory. We consider the contact, one-pion and two-pion exchange interactions and bridge the low energy constants of the $\Sigma_c\Sigma_c$ system to those of the $\Sigma_c^{(*)}\bar{D}^{(*)}$ systems through the quark-level ansatz for the contact interaction. We explore the influence of intermediate channels in the two-pion exchange diagrams of the $\Sigma_c\Sigma_c$ system. We obtain a deep bound state $[\Sigma_c\Sigma_c]_{J=0}^{I=0}$ and a shallow bound state $[\Sigma_c\Sigma_c]_{J=1}^{I=1}$. As a byproduct, we further investigate the interactions of the $\Lambda_c\Lambda_c$ and $\Lambda_c\Sigma_c$ systems.