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2207.02478
Jian Zhou Mr.
James Daniel Brandenburg, Zhangbu Xu, Wangmei Zha, Cheng Zhang, Jian Zhou, Yajin Zhou
Exploring gluon tomography with polarization dependent diffractive J/$\psi$ production
11 pages, 4 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study azimuthal asymmetries in diffractive J/$\psi$ production in ultraperipheral heavy-ion collisions at RHIC and LHC energies using the color glass condensate effective theory. Our calculation successfully describes azimuthal averaged $J/\psi$ production cross section measured by STAR and ALICE. We further predict very large $\cos 2\phi$ and $\cos 4\phi$ azimuthal asymmetries for diffractive $J/\psi$ production both in UPCs at RHIC and LHC energies and in eA collisions at EIC energy. These novel polarization dependent observables may provide complementary information for constraining gluon transverse spatial distribution inside large nuclei. As compared to all previous analysis of diffractive $J/\psi$ production, the essential new elements integrated in our theoretical calculations are: the double-slit interference effect, the linear polarization of coherent photons, and the final state soft photon radiation effect.
[ { "created": "Wed, 6 Jul 2022 07:09:19 GMT", "version": "v1" }, { "created": "Thu, 14 Jul 2022 03:20:45 GMT", "version": "v2" } ]
2022-07-15
[ [ "Brandenburg", "James Daniel", "" ], [ "Xu", "Zhangbu", "" ], [ "Zha", "Wangmei", "" ], [ "Zhang", "Cheng", "" ], [ "Zhou", "Jian", "" ], [ "Zhou", "Yajin", "" ] ]
We study azimuthal asymmetries in diffractive J/$\psi$ production in ultraperipheral heavy-ion collisions at RHIC and LHC energies using the color glass condensate effective theory. Our calculation successfully describes azimuthal averaged $J/\psi$ production cross section measured by STAR and ALICE. We further predict very large $\cos 2\phi$ and $\cos 4\phi$ azimuthal asymmetries for diffractive $J/\psi$ production both in UPCs at RHIC and LHC energies and in eA collisions at EIC energy. These novel polarization dependent observables may provide complementary information for constraining gluon transverse spatial distribution inside large nuclei. As compared to all previous analysis of diffractive $J/\psi$ production, the essential new elements integrated in our theoretical calculations are: the double-slit interference effect, the linear polarization of coherent photons, and the final state soft photon radiation effect.
0709.2902
Su Yan
Su Yan
Problems of the Sensitivity Parameter and Its Relation to the Time-varying Fundamental Couplings Problems
6 pages
null
null
null
hep-ph
null
The sensitivity parameter is widely used for quantifying fine tuning. However, examples show it fails to give correct results under certain circumstances. We argue that these problems only occur when calculating the sensitivity of a dimensionful mass parameter at one energy scale to the variation of a dimensionless coupling constant at another energy scale. Thus, by mechanisms such as dynamical symmetry breaking etc, the high sensitivity of the energy scale parameter (\Lambda) to the dimensionless coupling constant can affect the reliability of the sensitivity parameter through the renormalization invariant factor of the dimensionful parameter. Theoretically, These phenomena are similar to the problems associated with the time-varying coupling constant discovered recently. We argue that, the reliability of the sensitivity parameter can be improved if it is used properly.
[ { "created": "Tue, 18 Sep 2007 19:27:39 GMT", "version": "v1" }, { "created": "Tue, 23 Oct 2007 21:04:45 GMT", "version": "v2" } ]
2007-10-24
[ [ "Yan", "Su", "" ] ]
The sensitivity parameter is widely used for quantifying fine tuning. However, examples show it fails to give correct results under certain circumstances. We argue that these problems only occur when calculating the sensitivity of a dimensionful mass parameter at one energy scale to the variation of a dimensionless coupling constant at another energy scale. Thus, by mechanisms such as dynamical symmetry breaking etc, the high sensitivity of the energy scale parameter (\Lambda) to the dimensionless coupling constant can affect the reliability of the sensitivity parameter through the renormalization invariant factor of the dimensionful parameter. Theoretically, These phenomena are similar to the problems associated with the time-varying coupling constant discovered recently. We argue that, the reliability of the sensitivity parameter can be improved if it is used properly.
hep-ph/9812225
Antonio Masiero
A. Masiero (SISSA, Trieste) and T. Yanagida (Univ. of Tokyo)
Real CP Violation
6 pages
null
null
null
hep-ph
null
We propose a new mechanism called "real CP violation" to originate spontaneous CP violation. Starting with a CP conserving theory with scalar fields in the adjoint representation of a global or local non-abelian symmetry, we show that even though the VEV's of such scalars are real they give rise to a spontaneous violation of CP. We provide an illustrative example of how this new mechanism of CP violation can give rise to physically significant phases which produce a complex CKM mixing matrix. This mechanism may prove useful in string models with moduli in the adjoint representation as well as in tackling the strong CP problem.
[ { "created": "Wed, 2 Dec 1998 11:48:20 GMT", "version": "v1" } ]
2007-05-23
[ [ "Masiero", "A.", "", "SISSA, Trieste" ], [ "Yanagida", "T.", "", "Univ. of Tokyo" ] ]
We propose a new mechanism called "real CP violation" to originate spontaneous CP violation. Starting with a CP conserving theory with scalar fields in the adjoint representation of a global or local non-abelian symmetry, we show that even though the VEV's of such scalars are real they give rise to a spontaneous violation of CP. We provide an illustrative example of how this new mechanism of CP violation can give rise to physically significant phases which produce a complex CKM mixing matrix. This mechanism may prove useful in string models with moduli in the adjoint representation as well as in tackling the strong CP problem.
1609.09079
Miguel Escudero
Miguel Escudero, Asher Berlin, Dan Hooper and Meng-Xiang Lin
Toward (Finally!) Ruling Out Z and Higgs Mediated Dark Matter Models
Corrected an error on the relic abundance curves in the high mass region for the Z mediated models and for fermionic dark matter mediated by the Higgs. Some figures changed accordingly. Conclusions remain unchanged but for the case of a fermionic dark matter with purely axial couplings to the Z. References added
null
10.1088/1475-7516/2016/12/029
IFIC/16-66, FERMILAB-PUB-16-370-A
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In recent years, direct detection, indirect detection, and collider experiments have placed increasingly stringent constraints on particle dark matter, exploring much of the parameter space associated with the WIMP paradigm. In this paper, we focus on the subset of WIMP models in which the dark matter annihilates in the early universe through couplings to either the Standard Model $Z$ or the Standard Model Higgs boson. Considering fermionic, scalar, and vector dark matter candidates within a model-independent context, we find that the overwhelming majority of these dark matter candidates are already ruled out by existing experiments. In the case of $Z$ mediated dark matter, the only scenarios that are not currently excluded are those in which the dark matter is a fermion with an axial coupling and with a mass either within a few GeV of the $Z$ resonance ($m_{\rm DM} \simeq m_Z/2$) or greater than 200 GeV, or with a vector coupling and with $m_{\rm DM} > 6$ TeV. Several Higgs mediated scenarios are currently viable if the mass of the dark matter is near the Higgs pole ($m_{\rm DM} \simeq m_H/2$). Otherwise, the only scenarios that are not excluded are those in which the dark matter is a scalar (vector) heavier than 400 GeV (1160 GeV) with a Higgs portal coupling, or a fermion with a pseudoscalar (CP violating) coupling to the Standard Model Higgs boson. With the exception of dark matter with a purely pseudoscalar coupling to the Higgs, it is anticipated that planned direct detection experiments will probe nearly the entire range of models considered in this study.
[ { "created": "Wed, 28 Sep 2016 20:00:02 GMT", "version": "v1" }, { "created": "Thu, 24 Nov 2016 21:08:38 GMT", "version": "v2" } ]
2016-12-21
[ [ "Escudero", "Miguel", "" ], [ "Berlin", "Asher", "" ], [ "Hooper", "Dan", "" ], [ "Lin", "Meng-Xiang", "" ] ]
In recent years, direct detection, indirect detection, and collider experiments have placed increasingly stringent constraints on particle dark matter, exploring much of the parameter space associated with the WIMP paradigm. In this paper, we focus on the subset of WIMP models in which the dark matter annihilates in the early universe through couplings to either the Standard Model $Z$ or the Standard Model Higgs boson. Considering fermionic, scalar, and vector dark matter candidates within a model-independent context, we find that the overwhelming majority of these dark matter candidates are already ruled out by existing experiments. In the case of $Z$ mediated dark matter, the only scenarios that are not currently excluded are those in which the dark matter is a fermion with an axial coupling and with a mass either within a few GeV of the $Z$ resonance ($m_{\rm DM} \simeq m_Z/2$) or greater than 200 GeV, or with a vector coupling and with $m_{\rm DM} > 6$ TeV. Several Higgs mediated scenarios are currently viable if the mass of the dark matter is near the Higgs pole ($m_{\rm DM} \simeq m_H/2$). Otherwise, the only scenarios that are not excluded are those in which the dark matter is a scalar (vector) heavier than 400 GeV (1160 GeV) with a Higgs portal coupling, or a fermion with a pseudoscalar (CP violating) coupling to the Standard Model Higgs boson. With the exception of dark matter with a purely pseudoscalar coupling to the Higgs, it is anticipated that planned direct detection experiments will probe nearly the entire range of models considered in this study.
hep-ph/0506271
Aura Rosca
K. Moenig and A. Rosca
Two-photon width of the Higgs boson
Talk presented at LCWS05, Stanford, March 2005
null
null
null
hep-ph
null
This study investigates the potential of a photon collider for measuring the two photon partial width times the branching ratio of a light Higgs boson. The analysis is based on the reconstruction of the Higgs events produced in the gamma gamma -> h process, followed by Higgs decay into a b bbar pair. A statistical error of the measurement of the two-photon width times the b bbar branching ratio of the Higgs boson is found to be 1.7% with an integrated luminosity of 80 fb^-1 in the high energy part of the spectrum.
[ { "created": "Mon, 27 Jun 2005 11:27:13 GMT", "version": "v1" } ]
2009-09-29
[ [ "Moenig", "K.", "" ], [ "Rosca", "A.", "" ] ]
This study investigates the potential of a photon collider for measuring the two photon partial width times the branching ratio of a light Higgs boson. The analysis is based on the reconstruction of the Higgs events produced in the gamma gamma -> h process, followed by Higgs decay into a b bbar pair. A statistical error of the measurement of the two-photon width times the b bbar branching ratio of the Higgs boson is found to be 1.7% with an integrated luminosity of 80 fb^-1 in the high energy part of the spectrum.
1306.4356
Kher Sham Lim
Martin Holthausen, Kher Sham Lim
Quark and Leptonic Mixing Patterns from the Breakdown of a Common Discrete Flavor Symmetry
11 pages, 4 figures
null
10.1103/PhysRevD.88.033018
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Assuming the Majorana nature of neutrinos, we recently performed a scan of leptonic mixing patterns derived from finite discrete groups of order less than 1536. Here we show that the 3 groups identified there as giving predictions close to experiment, also contain another class of abelian subgroups that predict an interesting leading order quark mixing pattern where only the Cabibbo angle is generated at leading order. We further broaden our study by assuming that neutrinos are Dirac particles and find 4 groups of order up to 200 that can predict acceptable quark and leptonic mixing angles. Since large flavor groups allow for a multitude of leading order mixing patterns, we define a measure that is suitable to compare the predictivity of a given flavor group taking this fact into account. We give the result of this measure for a wide range of discrete flavor groups and identify the group (Z_18 \times Z_6) \rtimes S_3 as being most predictive in the sense of this measure. We further discuss alternative measures and their implications.
[ { "created": "Tue, 18 Jun 2013 21:17:37 GMT", "version": "v1" } ]
2013-09-04
[ [ "Holthausen", "Martin", "" ], [ "Lim", "Kher Sham", "" ] ]
Assuming the Majorana nature of neutrinos, we recently performed a scan of leptonic mixing patterns derived from finite discrete groups of order less than 1536. Here we show that the 3 groups identified there as giving predictions close to experiment, also contain another class of abelian subgroups that predict an interesting leading order quark mixing pattern where only the Cabibbo angle is generated at leading order. We further broaden our study by assuming that neutrinos are Dirac particles and find 4 groups of order up to 200 that can predict acceptable quark and leptonic mixing angles. Since large flavor groups allow for a multitude of leading order mixing patterns, we define a measure that is suitable to compare the predictivity of a given flavor group taking this fact into account. We give the result of this measure for a wide range of discrete flavor groups and identify the group (Z_18 \times Z_6) \rtimes S_3 as being most predictive in the sense of this measure. We further discuss alternative measures and their implications.
1701.07437
Chien-Yi Chen
Chien-Yi Chen, Maxim Pospelov, Yi-Ming Zhong
Muon Beam Experiments to Probe the Dark Sector
12 pages, 5 figures, 1 table; typo in equation 12 corrected
Phys. Rev. D 95, 115005 (2017)
10.1103/PhysRevD.95.115005
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A persistence of several anomalies in muon physics, such as the muon anomalous magnetic moment and the muonic hydrogen Lamb shift, hints at new light particles beyond the Standard Model. We address a subset of these models that have a new light scalar state with sizable couplings to muons and suppressed couplings to electrons. A novel way to search for such particles would be through muon beam-dump experiments by (1) missing momentum searches; (2) searches for decays with displaced vertices. The muon beams available at CERN and Fermilab present attractive opportunities for exploring the new scalar with a mass below the di-muon threshold, and potentially covering a range of relevant candidate models. For the models considered in this paper, both types of signals, muon missing momentum and anomalous energy deposition at a distance, can probe a substantial fraction of the unexplored parameter space of the new light scalar, including a region that can explain the muon anomalous magnetic moment discrepancy.
[ { "created": "Wed, 25 Jan 2017 19:00:02 GMT", "version": "v1" }, { "created": "Fri, 10 Nov 2017 19:03:27 GMT", "version": "v2" }, { "created": "Tue, 6 Nov 2018 20:11:05 GMT", "version": "v3" } ]
2018-11-08
[ [ "Chen", "Chien-Yi", "" ], [ "Pospelov", "Maxim", "" ], [ "Zhong", "Yi-Ming", "" ] ]
A persistence of several anomalies in muon physics, such as the muon anomalous magnetic moment and the muonic hydrogen Lamb shift, hints at new light particles beyond the Standard Model. We address a subset of these models that have a new light scalar state with sizable couplings to muons and suppressed couplings to electrons. A novel way to search for such particles would be through muon beam-dump experiments by (1) missing momentum searches; (2) searches for decays with displaced vertices. The muon beams available at CERN and Fermilab present attractive opportunities for exploring the new scalar with a mass below the di-muon threshold, and potentially covering a range of relevant candidate models. For the models considered in this paper, both types of signals, muon missing momentum and anomalous energy deposition at a distance, can probe a substantial fraction of the unexplored parameter space of the new light scalar, including a region that can explain the muon anomalous magnetic moment discrepancy.
hep-ph/0012176
Robert Harlander
Robert Harlander and William Kilgore
Higgs production in gluon fusion to order \alpha_s^4
3+2 pages, AMS-LaTeX. Talk given by RH at the Meeting of the Division of Particles and Fields of the American Physical Society (DPF2000), Columbus, Ohio, August 9--12, 2000
Int.J.Mod.Phys. A16S1A (2001) 305-307
10.1142/S0217751X01006760
BNL-HET-00/44
hep-ph
null
The calculation of the NNLO QCD corrections to the partonic process gg -> H is outlined. For the coupling of the Higgs boson to the gluons we use an effective Lagrangian in the limit of a heavy top quark. The focus is on the evaluation of the virtual two-loop corrections. It is shown that the leading pole terms are in agreement with the general formula by Catani.
[ { "created": "Thu, 14 Dec 2000 19:15:28 GMT", "version": "v1" } ]
2009-10-31
[ [ "Harlander", "Robert", "" ], [ "Kilgore", "William", "" ] ]
The calculation of the NNLO QCD corrections to the partonic process gg -> H is outlined. For the coupling of the Higgs boson to the gluons we use an effective Lagrangian in the limit of a heavy top quark. The focus is on the evaluation of the virtual two-loop corrections. It is shown that the leading pole terms are in agreement with the general formula by Catani.
1501.00456
Fernando Rossi Torres
F. Rossi-Torres, M. M. Guzzo and E. Kemp
Boundaries on Neutrino Mass from Supernovae Neutronization Burst by Liquid Argon Experiments
7 pages, 2 figures and 1 table
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This work presents an upper bound on the neutrino mass using the emission of $\nu_e$ from the neutronization burst of a core collapsing supernova at 10~kpc of distance and a progenitor star of 15~M$_\odot$. The calculations were done considering a 34 kton Liquid Argon Time Projection Chamber similar to the Far Detector proposal of the Long Baseline Neutrino Experiment (LBNE). We have performed a Monte Carlo simulation for the number of events integrated in 5~ms bins. Our results are $m_\nu<2.71$~eV and $0.18~\mbox{eV}<m_\nu<1.70$~eV, at 95\% C.L, assuming normal hierarchy and inverted hierarchy, respectively. We have analysed different configurations for the detector performance resulting in neutrino mass bound of $\mathcal{O}(1)$~eV.
[ { "created": "Fri, 2 Jan 2015 18:46:04 GMT", "version": "v1" } ]
2015-01-05
[ [ "Rossi-Torres", "F.", "" ], [ "Guzzo", "M. M.", "" ], [ "Kemp", "E.", "" ] ]
This work presents an upper bound on the neutrino mass using the emission of $\nu_e$ from the neutronization burst of a core collapsing supernova at 10~kpc of distance and a progenitor star of 15~M$_\odot$. The calculations were done considering a 34 kton Liquid Argon Time Projection Chamber similar to the Far Detector proposal of the Long Baseline Neutrino Experiment (LBNE). We have performed a Monte Carlo simulation for the number of events integrated in 5~ms bins. Our results are $m_\nu<2.71$~eV and $0.18~\mbox{eV}<m_\nu<1.70$~eV, at 95\% C.L, assuming normal hierarchy and inverted hierarchy, respectively. We have analysed different configurations for the detector performance resulting in neutrino mass bound of $\mathcal{O}(1)$~eV.
hep-ph/9709496
Sanghyeon Chang
Sanghyeon Chang, Claudio Coriano and L. E. Gordon
Rapidity Correlations and $\Delta G $ from Prompt Photon plus Jet Production in Polarized $pp$ Collisions
22 pages, 12 figures
Phys.Rev.D58:074002,1998
10.1103/PhysRevD.58.074002
ANL-HEP-PR-97-21, UFIFT-HEP-97-12, JLAB-THY-97-40
hep-ph
null
A study of prompt photon plus associated jet production is performed at next-to-leading order (O($\alpha\alpha_s^2$)) in QCD at $\sqrt{S}=200-500$ GeV, appropriate for the RHIC polarized $\vec{p}\vec{p}$ collider experiment. Momentum correlations between the jet and photon are examined and the utility of the process as a method for constraining the size and shape of the polarized gluon density of the proton $\Delta G$ is examined.
[ { "created": "Mon, 29 Sep 1997 16:59:48 GMT", "version": "v1" }, { "created": "Wed, 1 Oct 1997 21:11:18 GMT", "version": "v2" } ]
2014-11-17
[ [ "Chang", "Sanghyeon", "" ], [ "Coriano", "Claudio", "" ], [ "Gordon", "L. E.", "" ] ]
A study of prompt photon plus associated jet production is performed at next-to-leading order (O($\alpha\alpha_s^2$)) in QCD at $\sqrt{S}=200-500$ GeV, appropriate for the RHIC polarized $\vec{p}\vec{p}$ collider experiment. Momentum correlations between the jet and photon are examined and the utility of the process as a method for constraining the size and shape of the polarized gluon density of the proton $\Delta G$ is examined.
hep-ph/0107009
Marcello Ciafaloni
Marcello Ciafaloni, Martina Taiuti and A. H. Mueller
Diffusion corrections to the hard pomeron
18 pages, 3 Postscript figures
Nucl.Phys. B616 (2001) 349-366
10.1016/S0550-3213(01)00456-4
CERN-TH/2001-167
hep-ph
null
The high-energy behaviour of two-scale hard processes is investigated in the framework of small-x models with running coupling, having the Airy diffusion model as prototype. We show that, in some intermediate high-energy regime, the perturbative hard Pomeron exponent determines the energy dependence, and we prove that diffusion corrections have the form hinted at before in particular cases. We also discuss the breakdown of such regime at very large energies, and the onset of the non-perturbative Pomeron behaviour.
[ { "created": "Mon, 2 Jul 2001 13:43:24 GMT", "version": "v1" } ]
2009-11-07
[ [ "Ciafaloni", "Marcello", "" ], [ "Taiuti", "Martina", "" ], [ "Mueller", "A. H.", "" ] ]
The high-energy behaviour of two-scale hard processes is investigated in the framework of small-x models with running coupling, having the Airy diffusion model as prototype. We show that, in some intermediate high-energy regime, the perturbative hard Pomeron exponent determines the energy dependence, and we prove that diffusion corrections have the form hinted at before in particular cases. We also discuss the breakdown of such regime at very large energies, and the onset of the non-perturbative Pomeron behaviour.
hep-ph/0007077
Gagik Ter-Gazarian
G.T.Ter-Kazarian (BAO, Armenia)
Microscopic Theory of the Standard Model
Latex, 81 pages
null
null
BAO/2000-3
hep-ph
null
The operator manifold formalism (part I) enables the unification of the geometry and the field theory, and yields the quantization of geometry. This is the mathematical framework for our physical outlook that the geometry and fields, with the internal symmetries and all interactions, as well the four major principles of relativity (special and general), quantum, gauge and colour confinement, are derivative, and come into being simultaneously in the stable system of the underlying ``primordial structures''. In part II we attempt to develop, further, the microscopic approach to the Standard Model of particle physics, which enables an insight to the key problems of particle phenomenology. We suggest the microscopic theory of the unified electroweak interactions. The Higgs bosons have arisen on an analogy of the Cooper pairs in superconductivity. Besides of microscopic interpretation of all physical parameters the resulting theory also makes plausible following testable implications for the current experiments: 1. The Higgs bosons never could emerge in spacetime continuum, thus, they cannot be discovered in these experiments nor at any energy range. 2. For each of the three SM families of quarks and leptons there are corresponding heavy family partners with the same quantum numbers lying far above the electroweak scale, respectively, at the energy threshold values: $E_{1}>(419.6 \pm 12.0)GeV, \quad E_{2}= (457.6 \pm 13.2)GeV$ and $E_{3}=(521.4 \pm 15.0)GeV.$
[ { "created": "Sat, 8 Jul 2000 17:52:42 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ter-Kazarian", "G. T.", "", "BAO, Armenia" ] ]
The operator manifold formalism (part I) enables the unification of the geometry and the field theory, and yields the quantization of geometry. This is the mathematical framework for our physical outlook that the geometry and fields, with the internal symmetries and all interactions, as well the four major principles of relativity (special and general), quantum, gauge and colour confinement, are derivative, and come into being simultaneously in the stable system of the underlying ``primordial structures''. In part II we attempt to develop, further, the microscopic approach to the Standard Model of particle physics, which enables an insight to the key problems of particle phenomenology. We suggest the microscopic theory of the unified electroweak interactions. The Higgs bosons have arisen on an analogy of the Cooper pairs in superconductivity. Besides of microscopic interpretation of all physical parameters the resulting theory also makes plausible following testable implications for the current experiments: 1. The Higgs bosons never could emerge in spacetime continuum, thus, they cannot be discovered in these experiments nor at any energy range. 2. For each of the three SM families of quarks and leptons there are corresponding heavy family partners with the same quantum numbers lying far above the electroweak scale, respectively, at the energy threshold values: $E_{1}>(419.6 \pm 12.0)GeV, \quad E_{2}= (457.6 \pm 13.2)GeV$ and $E_{3}=(521.4 \pm 15.0)GeV.$
2305.07053
Shaouly Bar-Shalom
Shaouly Bar-Shalom
CP tests for high-$p_T$ multi-leptons
Talk given at the 57th Recontres de Moriond 2023, EW session (flavour physics)
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We propose a generic and model-independent search strategy for probing tree-level CP-violation in inclusive multi-lepton signals and we extend the standard expression for tree-level CP-violation in scattering processes at the LHC to include the cases where the initial state in not self-conjugate. We then use TeV-scale 4-fermion operators of the form $tu\ell\ell$ and $tc \ell \ell$ with complex Wilson coefficients as an illustrative example and show that it may generate ${\cal O}(10\%)$ CP asymmetries that should be accessible at the LHC with an integrated luminosity of ${\cal O}(1000)$ fb$^{-1}$
[ { "created": "Thu, 11 May 2023 18:00:03 GMT", "version": "v1" }, { "created": "Tue, 16 May 2023 08:34:35 GMT", "version": "v2" } ]
2023-05-17
[ [ "Bar-Shalom", "Shaouly", "" ] ]
We propose a generic and model-independent search strategy for probing tree-level CP-violation in inclusive multi-lepton signals and we extend the standard expression for tree-level CP-violation in scattering processes at the LHC to include the cases where the initial state in not self-conjugate. We then use TeV-scale 4-fermion operators of the form $tu\ell\ell$ and $tc \ell \ell$ with complex Wilson coefficients as an illustrative example and show that it may generate ${\cal O}(10\%)$ CP asymmetries that should be accessible at the LHC with an integrated luminosity of ${\cal O}(1000)$ fb$^{-1}$
hep-ph/0603077
Maxim Perelstein
Andreas Birkedal, Andrew Noble, Maxim Perelstein, and Andrew Spray
Little Higgs Dark Matter
22 pages, 9 figures. v3: a typo in Eq. (7) corrected. The rest of the paper is completely unaffected
Phys.Rev. D74 (2006) 035002
10.1103/PhysRevD.74.035002
null
hep-ph astro-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The introduction of T parity dramatically improves the consistency of Little Higgs models with precision electroweak data, and renders the lightest T-odd particle (LTP) stable. In the Littlest Higgs model with T parity, the LTP is typically the T-odd heavy photon, which is weakly interacting and can play the role of dark matter. We analyze the relic abundance of the heavy photon, including its coannihilations with other T-odd particles, and map out the regions of the parameter space where it can account for the observed dark matter. We evaluate the prospects for direct and indirect discovery of the heavy photon dark matter. The direct detection rates are quite low and a substantial improvement in experimental sensitivity would be required for observation. A substantial flux of energetic gamma rays is produced in the annihilation of the heavy photons in the galactic halo. This flux can be observed by the GLAST telescope, and, if the distribution of dark matter in the halo is favorable, by ground-based telescope arrays such as VERITAS and HESS.
[ { "created": "Thu, 9 Mar 2006 17:14:33 GMT", "version": "v1" }, { "created": "Wed, 29 Mar 2006 16:38:51 GMT", "version": "v2" }, { "created": "Fri, 3 Feb 2012 16:29:56 GMT", "version": "v3" } ]
2012-02-06
[ [ "Birkedal", "Andreas", "" ], [ "Noble", "Andrew", "" ], [ "Perelstein", "Maxim", "" ], [ "Spray", "Andrew", "" ] ]
The introduction of T parity dramatically improves the consistency of Little Higgs models with precision electroweak data, and renders the lightest T-odd particle (LTP) stable. In the Littlest Higgs model with T parity, the LTP is typically the T-odd heavy photon, which is weakly interacting and can play the role of dark matter. We analyze the relic abundance of the heavy photon, including its coannihilations with other T-odd particles, and map out the regions of the parameter space where it can account for the observed dark matter. We evaluate the prospects for direct and indirect discovery of the heavy photon dark matter. The direct detection rates are quite low and a substantial improvement in experimental sensitivity would be required for observation. A substantial flux of energetic gamma rays is produced in the annihilation of the heavy photons in the galactic halo. This flux can be observed by the GLAST telescope, and, if the distribution of dark matter in the halo is favorable, by ground-based telescope arrays such as VERITAS and HESS.
1803.06779
Masayasu Harada
Yusuke Takeda, Hiroaki Abuki, Masayasu Harada
A novel Dual Chiral Density Wave in nuclear matter based on a parity doublet structure
null
Phys. Rev. D 97, 094032 (2018)
10.1103/PhysRevD.97.094032
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the Dual Chiral Density Wave (DCDW) in nuclear matter using a hadronic model with the parity doublet structure. We first extend the ordinary DCDW ansatz so as to incorporate the effect of an explicit chiral symmetry breaking. Then via numerically evaluating and minimizing the effective potential, we determine the phase structure. We find, in addition to the ordinary DCDW phase where the space average of the chiral condensate vanishes, a new DCDW phase (sDCDW) with a nonvanishing space average depending on the value of the chiral invariant mass parameter.
[ { "created": "Mon, 19 Mar 2018 01:46:16 GMT", "version": "v1" } ]
2018-06-06
[ [ "Takeda", "Yusuke", "" ], [ "Abuki", "Hiroaki", "" ], [ "Harada", "Masayasu", "" ] ]
We study the Dual Chiral Density Wave (DCDW) in nuclear matter using a hadronic model with the parity doublet structure. We first extend the ordinary DCDW ansatz so as to incorporate the effect of an explicit chiral symmetry breaking. Then via numerically evaluating and minimizing the effective potential, we determine the phase structure. We find, in addition to the ordinary DCDW phase where the space average of the chiral condensate vanishes, a new DCDW phase (sDCDW) with a nonvanishing space average depending on the value of the chiral invariant mass parameter.
hep-ph/9408363
Daniel de Florian
D.de Florian, L.N.Epele, H.Fanchiotti, C.A.Garcia Canal, R.Sassot
Polarised parton distributions
13 pages and 7 figures (not included, available upon request DEFLO@venus.fisica.edu.ar)
Phys.Rev. D51 (1995) 37-43
10.1103/PhysRevD.51.37
null
hep-ph
null
We analyze spin dependent parton distributions consistent with the most recent measurements of the spin dependent deep inelastic scattering structure functions and obtained in the framework of the spin dilution model. Predictions for the doubly polarised proton-proton Drell-Yan asymmetry, for the high $p_{T}$ photon production mechanism and $J/\Psi$ excitation are calculated using these distributions and are shown to be particularly adequate to unveil the polarisation of partons in the proton.
[ { "created": "Wed, 24 Aug 1994 19:14:47 GMT", "version": "v1" } ]
2009-10-28
[ [ "de Florian", "D.", "" ], [ "Epele", "L. N.", "" ], [ "Fanchiotti", "H.", "" ], [ "Canal", "C. A. Garcia", "" ], [ "Sassot", "R.", "" ] ]
We analyze spin dependent parton distributions consistent with the most recent measurements of the spin dependent deep inelastic scattering structure functions and obtained in the framework of the spin dilution model. Predictions for the doubly polarised proton-proton Drell-Yan asymmetry, for the high $p_{T}$ photon production mechanism and $J/\Psi$ excitation are calculated using these distributions and are shown to be particularly adequate to unveil the polarisation of partons in the proton.
0806.2367
Priyotosh Bandyopadhyay
Priyotosh Bandyopadhyay, AseshKrishna Datta and Biswarup Mukhopadhyaya
Signatures of gaugino mass non-universality in cascade Higgs production at the LHC
14 pages, 22 figures
Phys.Lett.B670:5-11,2008
10.1016/j.physletb.2008.10.014
HRI-P-08-06-001, RECAPP-HRI-2008-007
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supersymmetric cascades, involving charginos and neutralinos at various stages, contribute in a significant way to Higgs production at the LHC. We explore the nature of such cascades, completely relaxing the universality of the gaugino masses. It is found that the deviation from the scenario with universal gaugino masses would be reflected in the relative production rates for the lightest Higgs and the charged Higgses, two characteristic particles of an extended Higgs sector.
[ { "created": "Sat, 14 Jun 2008 10:15:22 GMT", "version": "v1" } ]
2009-01-01
[ [ "Bandyopadhyay", "Priyotosh", "" ], [ "Datta", "AseshKrishna", "" ], [ "Mukhopadhyaya", "Biswarup", "" ] ]
Supersymmetric cascades, involving charginos and neutralinos at various stages, contribute in a significant way to Higgs production at the LHC. We explore the nature of such cascades, completely relaxing the universality of the gaugino masses. It is found that the deviation from the scenario with universal gaugino masses would be reflected in the relative production rates for the lightest Higgs and the charged Higgses, two characteristic particles of an extended Higgs sector.
2007.09832
Aiichi Iwazaki
Aiichi Iwazaki
A New Method for Detecting Axion With Cylindrical Superconductor
6 pages updated
null
10.1016/j.physletb.2020.135861
Nisho-1-2020
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a method for searching dark matter axion in axion-photon conversion. We consider a superconductor of cylindrical shape under strong magnetic field. The dark matter axion generates oscillating electric field which induces oscillating superconducting current in the surface of the superconductor. The current gives rise to dipole radiation with the frequency $m_a/2\pi$ given by axion mass $m_a$. We show that the radiation flux generated by the current is of the order of $10^{-18}$W under magnetic field $\sim 3$T in the case of radius $\sim 1$cm and length $\sim 10$cm of the cylindrical superconductor. %The superconducting current flows in the surface to the depth $\lambda\simeq 5\times 10^{-6}$cm. The large amount of the radiation flux arises because Cooper pairs with large number density ( $\sim 10^{22}/\rm cm^{3}$ ) is present in the superconductor. With the high detection sensitivity, we can simultaneously search wide bandwidth of the radio frequency with existing radio telescope.
[ { "created": "Mon, 20 Jul 2020 01:55:14 GMT", "version": "v1" }, { "created": "Thu, 3 Sep 2020 02:24:36 GMT", "version": "v2" } ]
2020-10-21
[ [ "Iwazaki", "Aiichi", "" ] ]
We propose a method for searching dark matter axion in axion-photon conversion. We consider a superconductor of cylindrical shape under strong magnetic field. The dark matter axion generates oscillating electric field which induces oscillating superconducting current in the surface of the superconductor. The current gives rise to dipole radiation with the frequency $m_a/2\pi$ given by axion mass $m_a$. We show that the radiation flux generated by the current is of the order of $10^{-18}$W under magnetic field $\sim 3$T in the case of radius $\sim 1$cm and length $\sim 10$cm of the cylindrical superconductor. %The superconducting current flows in the surface to the depth $\lambda\simeq 5\times 10^{-6}$cm. The large amount of the radiation flux arises because Cooper pairs with large number density ( $\sim 10^{22}/\rm cm^{3}$ ) is present in the superconductor. With the high detection sensitivity, we can simultaneously search wide bandwidth of the radio frequency with existing radio telescope.
2012.03990
Javier Alonso-Gonz\'alez
J. Alonso-Gonzalez, J.M. Lizana, V. Martinez-Fernandez, L. Merlo and S. Pokorski
Probing Effective Field Theory Approach in the CP Violating Minimal Linear $\sigma$ Model
32 pages, 6 figures, V2: improved discussion on the EFT treatment and on first order phase transition; references added; main results unchanged; version accepted for publication on EPJC
null
10.1140/epjc/s10052-021-09326-y
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Minimal Linear $\sigma$ Model is a useful theoretical laboratory. One can investigate in a perturbative renormalisable model the properties of the Higgs boson as a pseudo-Goldstone boson, the phenomenological effects of the radial mode of the field $\mathtt{s}$ which spontaneously breaks the global $SO(5)$ symmetry and the validity of conclusions based on the Effective Field Theory approach with the field $\mathtt{s}$ in the spectrum, after the decoupling of heavy degrees of freedom. In this paper all those issues are discussed in the framework of the Minimal Linear $\sigma$ Model with CP violating phases leading to pseudoscalar components in the effective Standard Model Yukawa couplings. Also the character of the electroweak phase transition in the presence of the field $\mathtt{s}$ is investigated.
[ { "created": "Mon, 7 Dec 2020 19:03:16 GMT", "version": "v1" }, { "created": "Thu, 10 Jun 2021 09:34:46 GMT", "version": "v2" } ]
2021-07-07
[ [ "Alonso-Gonzalez", "J.", "" ], [ "Lizana", "J. M.", "" ], [ "Martinez-Fernandez", "V.", "" ], [ "Merlo", "L.", "" ], [ "Pokorski", "S.", "" ] ]
The Minimal Linear $\sigma$ Model is a useful theoretical laboratory. One can investigate in a perturbative renormalisable model the properties of the Higgs boson as a pseudo-Goldstone boson, the phenomenological effects of the radial mode of the field $\mathtt{s}$ which spontaneously breaks the global $SO(5)$ symmetry and the validity of conclusions based on the Effective Field Theory approach with the field $\mathtt{s}$ in the spectrum, after the decoupling of heavy degrees of freedom. In this paper all those issues are discussed in the framework of the Minimal Linear $\sigma$ Model with CP violating phases leading to pseudoscalar components in the effective Standard Model Yukawa couplings. Also the character of the electroweak phase transition in the presence of the field $\mathtt{s}$ is investigated.
hep-ph/0208107
Taizan Watari
T. Watari and T. Yanagida
A Solution to the Doublet-Triplet Splitting Problem in the Type IIB Supergravity
61 pages
null
null
null
hep-ph hep-th
null
The doublet--triplet mass splitting problem is one of the most serious problems in supersymmetric grand unified theories (GUTs). A class of models based on a product gauge group, such as the SU(5)_{GUT} times U(3)_H or the SU(5)_{GUT} times U(2)_H, realize naturally the desired mass splitting that is protected by an unbroken R symmetry. It has been pointed out that various features in the models suggest that these product-group unification models are embedded in a supersymmetric brane world. We show an explicit construction of those models in the supersymmetric brane world based on the Type IIB supergravity in ten dimensions. We consider T^6/(Z_{12} times Z_2) orientifold for the compactified six extra dimensions. We find that all of the particles needed for the GUT-symmetry-breaking sector are obtained from the D-brane fluctuations. The three families of quarks and leptons are introduced at an orbifold singularity, although their origin remains unexplained. This paper includes extensive discussion on anomaly cancellation in a given orbifold geometry. Relation to the Type IIB string theory, realization of R symmetry as a rotation of extra-dimensional space, and effective superpotential at low energies are also discussed.
[ { "created": "Sun, 11 Aug 2002 15:56:56 GMT", "version": "v1" } ]
2007-05-23
[ [ "Watari", "T.", "" ], [ "Yanagida", "T.", "" ] ]
The doublet--triplet mass splitting problem is one of the most serious problems in supersymmetric grand unified theories (GUTs). A class of models based on a product gauge group, such as the SU(5)_{GUT} times U(3)_H or the SU(5)_{GUT} times U(2)_H, realize naturally the desired mass splitting that is protected by an unbroken R symmetry. It has been pointed out that various features in the models suggest that these product-group unification models are embedded in a supersymmetric brane world. We show an explicit construction of those models in the supersymmetric brane world based on the Type IIB supergravity in ten dimensions. We consider T^6/(Z_{12} times Z_2) orientifold for the compactified six extra dimensions. We find that all of the particles needed for the GUT-symmetry-breaking sector are obtained from the D-brane fluctuations. The three families of quarks and leptons are introduced at an orbifold singularity, although their origin remains unexplained. This paper includes extensive discussion on anomaly cancellation in a given orbifold geometry. Relation to the Type IIB string theory, realization of R symmetry as a rotation of extra-dimensional space, and effective superpotential at low energies are also discussed.
1804.02345
Bruno Moreira
V. P. Goncalves, B. D. Moreira
$\eta_c$ photoproduction at LHC energies
4 pages, 3 figures, 1 table. Poster presented at the XIV International Workshop on Hadron Physics, Florian\'opolis, Brazil, March 2018
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this contribution, we study the inclusive and diffractive $\eta_{c}$ photoproduction in $pp$ and $pPb$ ultra-peripheral collisions (UPC's) at the LHC Run 2 energies. The quarkonium production is studied using nonrelativistic quantum chromodynamics (NRQCD) formalism. We present predictions for rapidity and transverse momentum distributions for the $\eta_c$ photoproduction and present our estimate for the total cross sections at the Run 2 energies.
[ { "created": "Fri, 6 Apr 2018 16:21:27 GMT", "version": "v1" } ]
2018-04-09
[ [ "Goncalves", "V. P.", "" ], [ "Moreira", "B. D.", "" ] ]
In this contribution, we study the inclusive and diffractive $\eta_{c}$ photoproduction in $pp$ and $pPb$ ultra-peripheral collisions (UPC's) at the LHC Run 2 energies. The quarkonium production is studied using nonrelativistic quantum chromodynamics (NRQCD) formalism. We present predictions for rapidity and transverse momentum distributions for the $\eta_c$ photoproduction and present our estimate for the total cross sections at the Run 2 energies.
1504.07222
Ma\'ira Santos Dutra
Ma\'ira Dutra, C. A. de S. Pires, P. S. Rodrigues da Silva
Majorana Dark Matter in Minimal Higgs Portal Models after LUX
20 pages, 12 figures
null
10.1007/JHEP09(2015)147
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the Singlet Majorana fermion dark matter model, in which the standard model particles interact with the dark sector through the mixing of a singlet scalar and the Higgs boson. In this model both the dark matter and the singlet scalar carry lepton number, the latter being a bilepton. We suppose the existence of a $Z_2$ symmetry, remnant of some high energy local symmetry breaking, that stabilizes the Majorana fermion. We analyzed the parameter space of this model and found that the lepton number symmetry breaking scale, drove by the singlet scalar, is constrained to be within hundreds to thousands of GeV, so as to conform with the observed dark matter relic density. Finally, we address the direct detection and invisible Higgs decay complementarity, confronting our model with recent LUX and LHC constraints, as well as XENON1T prospects.
[ { "created": "Mon, 27 Apr 2015 19:38:27 GMT", "version": "v1" } ]
2015-09-30
[ [ "Dutra", "Maíra", "" ], [ "Pires", "C. A. de S.", "" ], [ "da Silva", "P. S. Rodrigues", "" ] ]
We consider the Singlet Majorana fermion dark matter model, in which the standard model particles interact with the dark sector through the mixing of a singlet scalar and the Higgs boson. In this model both the dark matter and the singlet scalar carry lepton number, the latter being a bilepton. We suppose the existence of a $Z_2$ symmetry, remnant of some high energy local symmetry breaking, that stabilizes the Majorana fermion. We analyzed the parameter space of this model and found that the lepton number symmetry breaking scale, drove by the singlet scalar, is constrained to be within hundreds to thousands of GeV, so as to conform with the observed dark matter relic density. Finally, we address the direct detection and invisible Higgs decay complementarity, confronting our model with recent LUX and LHC constraints, as well as XENON1T prospects.
hep-ph/9405287
David Griegel
David K. Griegel and Thomas D. Cohen
QCD sum rules vs. chiral perturbation theory
9 pages (no figures), UMPP 94-136
Phys.Lett. B333 (1994) 27-32
10.1016/0370-2693(94)91003-0
null
hep-ph
null
QCD sum rules are useful tools for studying the spectral properties of hadrons; however, assumptions underlying standard sum-rule analyses can lead to inconsistencies with known results of chiral perturbation theory. This possibility is demonstrated with QCD sum-rule extractions of the nucleon mass and $\sigma$ term. In both cases, inconsistent chiral behavior leads to an uncertainty in the sum-rule predictions of $\sim 100\,\text{MeV}$.
[ { "created": "Fri, 13 May 1994 19:36:17 GMT", "version": "v1" } ]
2009-10-28
[ [ "Griegel", "David K.", "" ], [ "Cohen", "Thomas D.", "" ] ]
QCD sum rules are useful tools for studying the spectral properties of hadrons; however, assumptions underlying standard sum-rule analyses can lead to inconsistencies with known results of chiral perturbation theory. This possibility is demonstrated with QCD sum-rule extractions of the nucleon mass and $\sigma$ term. In both cases, inconsistent chiral behavior leads to an uncertainty in the sum-rule predictions of $\sim 100\,\text{MeV}$.
1208.1163
Raoul Nakhmanson-Kulish
Raul Nakhmanson-Kulish
Proposition of direct experiment to study the properties of the neutrino with inverted helicity
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Author proposes the idea of direct, affordable in the foreseeable future experiment that could determine whether the neutrino are Dirac or Majorana particles.
[ { "created": "Mon, 6 Aug 2012 14:07:36 GMT", "version": "v1" } ]
2012-08-16
[ [ "Nakhmanson-Kulish", "Raul", "" ] ]
Author proposes the idea of direct, affordable in the foreseeable future experiment that could determine whether the neutrino are Dirac or Majorana particles.
2403.06038
Frank Wilczek
Frank Wilczek
QCD at 50: Golden Anniversary, Golden Insights, Golden Opportunities
Keynote speech at 2023 Majorana Summer School (Erice), also delivered elsewhere. 30 pages, 9 figures
null
null
null
hep-ph hep-lat hep-th physics.hist-ph
http://creativecommons.org/licenses/by/4.0/
The bulk of this paper centers around the tension between confinement and freedom in QCD. I discuss how it can be understood heuristically as a manifestation of self-adhesive glue and how it fits within the larger contexts of energy-time uncertainty and $\textit{real virtuality}$. I discuss the possible emergence of $\textit{treeons}$ as a tangible ingredient of (at least) pure gluon $SU(3)$. I propose $\textit{flux channeling}$ as a method to address that and allied questions about triality flux numerically, and indicate how to implement it for electric and magnetic flux in material systems. That bulk is framed with broad-stroke, necessarily selective sketches of the past and possible future of strong interaction physics. At the end, I've added an expression of gratitude for my formative experience at the Erice school, in 1973.
[ { "created": "Sat, 9 Mar 2024 23:12:41 GMT", "version": "v1" } ]
2024-03-15
[ [ "Wilczek", "Frank", "" ] ]
The bulk of this paper centers around the tension between confinement and freedom in QCD. I discuss how it can be understood heuristically as a manifestation of self-adhesive glue and how it fits within the larger contexts of energy-time uncertainty and $\textit{real virtuality}$. I discuss the possible emergence of $\textit{treeons}$ as a tangible ingredient of (at least) pure gluon $SU(3)$. I propose $\textit{flux channeling}$ as a method to address that and allied questions about triality flux numerically, and indicate how to implement it for electric and magnetic flux in material systems. That bulk is framed with broad-stroke, necessarily selective sketches of the past and possible future of strong interaction physics. At the end, I've added an expression of gratitude for my formative experience at the Erice school, in 1973.
hep-ph/0509259
Rainer Schicker M
Rainer Schicker
The ALICE detector at LHC
4 pages, Proceedings of XIth International Conference on Elastic and Diffractive Scattering, Blois, France, may 2005
null
null
null
hep-ph nucl-ex
null
The ALICE experiment at the Large Hadron Collider LHC is presented, and an overview of its physics program is given. A few specific observables are discussed in order to illustrate the physics potential of ALICE.
[ { "created": "Fri, 23 Sep 2005 12:37:33 GMT", "version": "v1" }, { "created": "Wed, 5 Oct 2005 08:30:38 GMT", "version": "v2" } ]
2016-09-06
[ [ "Schicker", "Rainer", "" ] ]
The ALICE experiment at the Large Hadron Collider LHC is presented, and an overview of its physics program is given. A few specific observables are discussed in order to illustrate the physics potential of ALICE.
1311.4893
Rikkert Frederix
Rikkert Frederix
The top induced backgrounds to Higgs production in the WW -> llvv decay channel at NLO in QCD
4 pages, 5 figures
Phys.Rev.Lett.112:082002,2014
10.1103/PhysRevLett.112.082002
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the complete NLO contributions to the pp -> e^+ v_e mu^- vbar_m b bbar + X process in the four flavour scheme, i.e. with massive b quarks, and its contribution to the H -> WW -> llvv measurement in the 1-jet bin at the LHC. This background process includes top pair, single top and non-top quark-resonant contributions. The uncertainty at NLO from renormalisation and factorisation scale dependence is about +30% -20%. We show that the NLO corrections are relatively small, and that separating this background in top pair, Wt and b-quark associated llvv is a fair approximation.
[ { "created": "Tue, 19 Nov 2013 21:13:10 GMT", "version": "v1" }, { "created": "Fri, 2 May 2014 15:11:47 GMT", "version": "v2" } ]
2015-06-17
[ [ "Frederix", "Rikkert", "" ] ]
We present the complete NLO contributions to the pp -> e^+ v_e mu^- vbar_m b bbar + X process in the four flavour scheme, i.e. with massive b quarks, and its contribution to the H -> WW -> llvv measurement in the 1-jet bin at the LHC. This background process includes top pair, single top and non-top quark-resonant contributions. The uncertainty at NLO from renormalisation and factorisation scale dependence is about +30% -20%. We show that the NLO corrections are relatively small, and that separating this background in top pair, Wt and b-quark associated llvv is a fair approximation.
1208.0898
Eugene Levin
E. Gotsman (Tel Aviv Un.), E. Levin (Tel Aviv Un./UTFSM) and U. Maor (Tel Aviv Un.)
Description of LHC data in a soft interaction model
11 pages with 7 figures in eps formats
null
10.1016/j.physletb.2012.08.042
TAUP-2155/12
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show in this paper that we have found a set of parameters in our model for the soft interactions at high energy, that successfully describes all high energy experimental data, including the LHC data. This model is based on a single Pomeron with large intercept $\Delta_\pom = 0.23$ and slope $\alpha'_\pom = 0$, that describes both long and short distance processes. It also provides a natural matching with perturbative QCD. All features of our model are similar to the expectations of N=4 SYM, which at present is the only theory that is able to treat srong interactions on a theoretical basis.
[ { "created": "Sat, 4 Aug 2012 07:14:44 GMT", "version": "v1" } ]
2015-06-11
[ [ "Gotsman", "E.", "", "Tel Aviv Un." ], [ "Levin", "E.", "", "Tel Aviv Un./UTFSM" ], [ "Maor", "U.", "", "Tel Aviv Un." ] ]
We show in this paper that we have found a set of parameters in our model for the soft interactions at high energy, that successfully describes all high energy experimental data, including the LHC data. This model is based on a single Pomeron with large intercept $\Delta_\pom = 0.23$ and slope $\alpha'_\pom = 0$, that describes both long and short distance processes. It also provides a natural matching with perturbative QCD. All features of our model are similar to the expectations of N=4 SYM, which at present is the only theory that is able to treat srong interactions on a theoretical basis.
1407.2532
Andrew Papanastasiou
A. Broggio, A.S. Papanastasiou and A. Signer
Renormalization-group improved fully differential cross sections for top pair production
null
null
10.1007/JHEP10(2014)098
DESY 14-104, PSI-PR-14-04, ZU-TH 21/14
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend approximate next-to-next-to-leading order results for top-pair production to include the semi-leptonic decays of top quarks in the narrow-width approximation. The new hard-scattering kernels are implemented in a fully differential parton-level Monte Carlo that allows for the study of any IR-safe observable constructed from the momenta of the decay products of the top. Our best predictions are given by approximate NNLO corrections in the production matched to a fixed order calculation with NLO corrections in both the production and decay subprocesses. Being fully differential enables us to make comparisons between approximate results derived via different (PIM and 1PI) kinematics for arbitrary distributions. These comparisons reveal that the renormalization-group framework, from which the approximate results are derived, is rather robust in the sense that applying a realistic error estimate allows us to obtain a reliable prediction with a reduced theoretical error for generic observables and analysis cuts.
[ { "created": "Wed, 9 Jul 2014 15:46:38 GMT", "version": "v1" } ]
2015-06-22
[ [ "Broggio", "A.", "" ], [ "Papanastasiou", "A. S.", "" ], [ "Signer", "A.", "" ] ]
We extend approximate next-to-next-to-leading order results for top-pair production to include the semi-leptonic decays of top quarks in the narrow-width approximation. The new hard-scattering kernels are implemented in a fully differential parton-level Monte Carlo that allows for the study of any IR-safe observable constructed from the momenta of the decay products of the top. Our best predictions are given by approximate NNLO corrections in the production matched to a fixed order calculation with NLO corrections in both the production and decay subprocesses. Being fully differential enables us to make comparisons between approximate results derived via different (PIM and 1PI) kinematics for arbitrary distributions. These comparisons reveal that the renormalization-group framework, from which the approximate results are derived, is rather robust in the sense that applying a realistic error estimate allows us to obtain a reliable prediction with a reduced theoretical error for generic observables and analysis cuts.
hep-ph/9910555
Oleg Teryaev
A.V. Efremov and O. V. Teryaev
On the Oscillations of the Tensor Spin Structure Function
LATEX, 5 pages Published in the Proceedings of the conference "Deuteron-93", JINR E2-94-95, p.206-210
null
null
null
hep-ph
null
The smallness of the deuteron tensor spin structure function is the necessary condition to extract neutron $g_1$ function neglecting the nuclear effects. The oscillating behavior of the quark tensor spin structure function leading to the zero first moment is shown to be the straightforward consequence of the factorization property and Lorentz covariance. For the singlet contribution the momentum conservation leads to the zero second moment also. The deviations from zero directly measure the gluon contribution.
[ { "created": "Sun, 31 Oct 1999 22:01:19 GMT", "version": "v1" } ]
2007-05-23
[ [ "Efremov", "A. V.", "" ], [ "Teryaev", "O. V.", "" ] ]
The smallness of the deuteron tensor spin structure function is the necessary condition to extract neutron $g_1$ function neglecting the nuclear effects. The oscillating behavior of the quark tensor spin structure function leading to the zero first moment is shown to be the straightforward consequence of the factorization property and Lorentz covariance. For the singlet contribution the momentum conservation leads to the zero second moment also. The deviations from zero directly measure the gluon contribution.
hep-ph/9408264
A. Leonidov
A.V.Leonidov, G.M.Zinovjev
On the Deconfinement Phase Transition in the Resonance Gas
7 pages, plain LaTeX, BI-TP 94/40
JETP Lett. 63 (1996) 510-515
10.1134/1.567057
null
hep-ph
null
We obtain the constraints on the ruling parameters of the dense hadronic gas model at the critical temperature and propose the quasiuniversal ratios of the thermodynamic quantities. The possible appearence of thermodynamical instability in such a model is discussed.
[ { "created": "Wed, 10 Aug 1994 14:11:58 GMT", "version": "v1" } ]
2009-10-28
[ [ "Leonidov", "A. V.", "" ], [ "Zinovjev", "G. M.", "" ] ]
We obtain the constraints on the ruling parameters of the dense hadronic gas model at the critical temperature and propose the quasiuniversal ratios of the thermodynamic quantities. The possible appearence of thermodynamical instability in such a model is discussed.
2301.10721
William Tavares
Arthur E. B. Pasqualotto, Ricardo L. S. Farias, William R. Tavares, Sidney S. Avancini and Gast\~ao Krein
Causality violation and the speed of sound of hot and dense quark matter in the Nambu--Jona-Lasinio model
Typos corrected, comments added. Matches published version
Phys.Rev.D 107 (2023) 9, 096017
10.1103/PhysRevD.107.096017
null
hep-ph hep-lat hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Nambu--Jona-Lasinio model is widely used to study strong-interaction phenomena in vacuum and quark matter. Since the model is nonrenormalizable, one needs to work within a specific regularization scheme to obtain finite results. Here we show that a commonly used cutoff regularization scheme leads to unphysical results, such as superluminal speed of sound and wrong high-temperature behavior of the specific heat and other thermodynamical quantities. Such a troublesome feature of the cutoff regularization invalidates the model for temperature and baryon density values relevant to the phenomenology of heavy-ion collisions and compact stars. We show that the source of the problems stems from cutting off momentum modes in finite integrals depending on thermal distribution functions in the grand canonical potential. The problems go away when taking into account the full momentum range of those integrals. Explicit examples are worked out in the SU(2)-flavor version of the model.
[ { "created": "Wed, 25 Jan 2023 17:30:36 GMT", "version": "v1" }, { "created": "Mon, 12 Jun 2023 14:43:22 GMT", "version": "v2" } ]
2023-06-13
[ [ "Pasqualotto", "Arthur E. B.", "" ], [ "Farias", "Ricardo L. S.", "" ], [ "Tavares", "William R.", "" ], [ "Avancini", "Sidney S.", "" ], [ "Krein", "Gastão", "" ] ]
The Nambu--Jona-Lasinio model is widely used to study strong-interaction phenomena in vacuum and quark matter. Since the model is nonrenormalizable, one needs to work within a specific regularization scheme to obtain finite results. Here we show that a commonly used cutoff regularization scheme leads to unphysical results, such as superluminal speed of sound and wrong high-temperature behavior of the specific heat and other thermodynamical quantities. Such a troublesome feature of the cutoff regularization invalidates the model for temperature and baryon density values relevant to the phenomenology of heavy-ion collisions and compact stars. We show that the source of the problems stems from cutting off momentum modes in finite integrals depending on thermal distribution functions in the grand canonical potential. The problems go away when taking into account the full momentum range of those integrals. Explicit examples are worked out in the SU(2)-flavor version of the model.
hep-ph/0210095
Steen H. Hansen
C. Caprini, S. H. Hansen, M. Kunz
Observational constraint on the fourth derivative of the inflaton potential
3 pages, 3 figures
Mon.Not.Roy.Astron.Soc. 339 (2003) 212-214
10.1046/j.1365-8711.2003.06164.x
null
hep-ph astro-ph
null
We consider the flow-equations for the 3 slow-roll parameters n_S (scalar spectral index), r (tensor to scalar ratio), and dn_S/dlnk (running of the spectral index). We show that the combination of these flow-equations with the observational bounds from cosmic microwave background and large scale structure allows one to put a lower bound on the fourth derivative of the inflationary potential, M_P^4(V''''/V) > -0.02.
[ { "created": "Mon, 7 Oct 2002 09:40:59 GMT", "version": "v1" } ]
2009-11-07
[ [ "Caprini", "C.", "" ], [ "Hansen", "S. H.", "" ], [ "Kunz", "M.", "" ] ]
We consider the flow-equations for the 3 slow-roll parameters n_S (scalar spectral index), r (tensor to scalar ratio), and dn_S/dlnk (running of the spectral index). We show that the combination of these flow-equations with the observational bounds from cosmic microwave background and large scale structure allows one to put a lower bound on the fourth derivative of the inflationary potential, M_P^4(V''''/V) > -0.02.
1012.5985
Alan Kostelecky
Jorge S. Diaz and Alan Kostelecky
Three-parameter Lorentz-violating texture for neutrino mixing
5 pages, accepted for publication in Physics Letters B
Phys.Lett.B700:25-28,2011
10.1016/j.physletb.2011.04.049
IUHET 552, December 2010
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A three-parameter model of neutrino oscillations based on a simple Lorentz- and CPT-violating texture is presented. The model is consistent with established data and naturally generates low-energy and neutrino-antineutrino anomalies of the MiniBooNE type. A one-parameter extension incorporates the MINOS anomaly, while a simple texture enhancement accommodates the LSND signal.
[ { "created": "Wed, 29 Dec 2010 17:24:44 GMT", "version": "v1" }, { "created": "Wed, 4 May 2011 15:13:19 GMT", "version": "v2" } ]
2015-05-20
[ [ "Diaz", "Jorge S.", "" ], [ "Kostelecky", "Alan", "" ] ]
A three-parameter model of neutrino oscillations based on a simple Lorentz- and CPT-violating texture is presented. The model is consistent with established data and naturally generates low-energy and neutrino-antineutrino anomalies of the MiniBooNE type. A one-parameter extension incorporates the MINOS anomaly, while a simple texture enhancement accommodates the LSND signal.
0804.3545
Elvio Di Salvo
E. Di Salvo
Deep Inelastic Processes and the Equations of Motion
49 pages, 5 figures
International Journal of Physical Sciences 7 (2012) 867
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that the Politzer theorem on the equations of motion implies approximate constraints on the quark correlator, restricting considerably, for sufficiently large Q^2, the number of independent distribution functions that characterize the internal structure of the nucleon, and of independent fragmentation functions. This result leads us to suggesting an alternative method for determining transversity. Moreover our approach implies predictions on the Q^2-dependence of some azimuthal asymmetries, like Sivers, Qiu-Sterman and Collins asymmetry. Lastly, we discuss some implications on the Burkhardt-Cottingham and Efremov-Leader-Teryaev sum rules.
[ { "created": "Tue, 22 Apr 2008 14:47:08 GMT", "version": "v1" }, { "created": "Sat, 28 Apr 2012 13:41:09 GMT", "version": "v2" } ]
2012-05-01
[ [ "Di Salvo", "E.", "" ] ]
We show that the Politzer theorem on the equations of motion implies approximate constraints on the quark correlator, restricting considerably, for sufficiently large Q^2, the number of independent distribution functions that characterize the internal structure of the nucleon, and of independent fragmentation functions. This result leads us to suggesting an alternative method for determining transversity. Moreover our approach implies predictions on the Q^2-dependence of some azimuthal asymmetries, like Sivers, Qiu-Sterman and Collins asymmetry. Lastly, we discuss some implications on the Burkhardt-Cottingham and Efremov-Leader-Teryaev sum rules.
hep-ph/9308210
null
A. Deandrea, N. Di Bartolomeo, R. Gatto and G. Nardulli
Two Body Non Leptonic Decays of B and B_s Mesons
18 pages, LaTeX (style article), UGVA-DPT 1993/07-824 and BARI-TH/155
Phys.Lett.B318:549-558,1993
10.1016/0370-2693(93)91554-Z
null
hep-ph
null
We perform an analysis of two-body non leptonic decays of $B$ and $B_s$ mesons in the factorization approximation. We make use of the semileptonic decay amplitudes previously calculated on the basis of an effective lagrangian satisfying chiral and heavy quark symmetries and including spin 1 resonances. Exclusive semileptonic $D$-decay data are used as experimental input. Our results compare favorably with data, whenever they are available and indicate a positive value for the ratio of non leptonic coefficients $a_2/a_1$, similarly to previous studies.
[ { "created": "Tue, 3 Aug 1993 11:54:00 GMT", "version": "v1" } ]
2011-08-17
[ [ "Deandrea", "A.", "" ], [ "Di Bartolomeo", "N.", "" ], [ "Gatto", "R.", "" ], [ "Nardulli", "G.", "" ] ]
We perform an analysis of two-body non leptonic decays of $B$ and $B_s$ mesons in the factorization approximation. We make use of the semileptonic decay amplitudes previously calculated on the basis of an effective lagrangian satisfying chiral and heavy quark symmetries and including spin 1 resonances. Exclusive semileptonic $D$-decay data are used as experimental input. Our results compare favorably with data, whenever they are available and indicate a positive value for the ratio of non leptonic coefficients $a_2/a_1$, similarly to previous studies.
0810.5557
Graham D. Kribs
Roni Harnik, Graham D. Kribs
An Effective Theory of Dirac Dark Matter
11 pages, 8 figures
Phys.Rev.D79:095007,2009
10.1103/PhysRevD.79.095007
null
hep-ph astro-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A stable Dirac fermion with four-fermion interactions to leptons suppressed by a scale Lambda ~ 1 TeV is shown to provide a viable candidate for dark matter. The thermal relic abundance matches cosmology, while nuclear recoil direct detection bounds are automatically avoided in the absence of (large) couplings to quarks. The annihilation cross section in the early Universe is the same as the annihilation in our galactic neighborhood. This allows Dirac fermion dark matter to naturally explain the positron ratio excess observed by PAMELA with a minimal boost factor, given present astrophysical uncertainties. We use the Galprop program for propagation of signal and background; we discuss in detail the uncertainties resulting from the propagation parameters and, more importantly, the injected spectra. Fermi/GLAST has an opportunity to see a feature in the gamma-ray spectrum at the mass of the Dirac fermion. The excess observed by ATIC/PPB-BETS may also be explained with Dirac dark matter that is heavy. A supersymmetric model with a Dirac bino provides a viable UV model of the effective theory. The dominance of the leptonic operators, and thus the observation of an excess in positrons and not in anti-protons, is naturally explained by the large hypercharge and low mass of sleptons as compared with squarks. Minimizing the boost factor implies the right-handed selectron is the lightest slepton, which is characteristic of our model. Selectrons (or sleptons) with mass less than a few hundred GeV are an inescapable consequence awaiting discovery at the LHC.
[ { "created": "Fri, 31 Oct 2008 19:33:03 GMT", "version": "v1" } ]
2010-04-28
[ [ "Harnik", "Roni", "" ], [ "Kribs", "Graham D.", "" ] ]
A stable Dirac fermion with four-fermion interactions to leptons suppressed by a scale Lambda ~ 1 TeV is shown to provide a viable candidate for dark matter. The thermal relic abundance matches cosmology, while nuclear recoil direct detection bounds are automatically avoided in the absence of (large) couplings to quarks. The annihilation cross section in the early Universe is the same as the annihilation in our galactic neighborhood. This allows Dirac fermion dark matter to naturally explain the positron ratio excess observed by PAMELA with a minimal boost factor, given present astrophysical uncertainties. We use the Galprop program for propagation of signal and background; we discuss in detail the uncertainties resulting from the propagation parameters and, more importantly, the injected spectra. Fermi/GLAST has an opportunity to see a feature in the gamma-ray spectrum at the mass of the Dirac fermion. The excess observed by ATIC/PPB-BETS may also be explained with Dirac dark matter that is heavy. A supersymmetric model with a Dirac bino provides a viable UV model of the effective theory. The dominance of the leptonic operators, and thus the observation of an excess in positrons and not in anti-protons, is naturally explained by the large hypercharge and low mass of sleptons as compared with squarks. Minimizing the boost factor implies the right-handed selectron is the lightest slepton, which is characteristic of our model. Selectrons (or sleptons) with mass less than a few hundred GeV are an inescapable consequence awaiting discovery at the LHC.
1203.4853
Olga Voskresenskaya
A.V. Tarasov, H.T. Torosyan, and O.O. Voskresenskaya
A Quasiclassical Approximation in the Theory of the Landau-Pomeranchuk Effect
9 pages, no figures, LaTEX; v2: PDFLaTeX, 7 pages, an updated version
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the improved value of the screening angular parameter in the quasiclassical approximation of the Moliere multiple scattering theory we show that the best agreement between the Migdal theory of the LPM-effect and experiment is achieved if the multiple scattering of electrons by target atoms is described using the quasiclassical approximation instead of the traditionally used Born one.
[ { "created": "Wed, 21 Mar 2012 23:09:07 GMT", "version": "v1" }, { "created": "Fri, 7 Feb 2014 20:46:41 GMT", "version": "v2" } ]
2014-02-10
[ [ "Tarasov", "A. V.", "" ], [ "Torosyan", "H. T.", "" ], [ "Voskresenskaya", "O. O.", "" ] ]
Using the improved value of the screening angular parameter in the quasiclassical approximation of the Moliere multiple scattering theory we show that the best agreement between the Migdal theory of the LPM-effect and experiment is achieved if the multiple scattering of electrons by target atoms is described using the quasiclassical approximation instead of the traditionally used Born one.
0905.2382
Pomita Ghoshal
Raj Gandhi, Pomita Ghoshal, Srubabati Goswami, S Uma Sankar
Mass Hierarchy Determination for $\theta_{13}=0$ and Atmospheric Neutrinos
12 pages, 3 figures. Focus of the paper changed to atmospheric neutrinos, but main result unchanged. Title changed to reflect the change in focus
Mod. Phys. Lett. A25:2255-2266,2010
10.1142/S0217732310033086
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the possibility of determining the neutrino mass hierarchy in the limit \theta_{13} = 0 using atmospheric neutrinos as the source. In this limit, in which \theta_{13} driven matter effects are absent, independent measurements of \Delta_{31} and \Delta_{32} can, in principle, lead to hierarchy determination. Since the difference between these two is \Delta_{21}, one needs an experimental arrangement where \Delta_{21} L/E \gtrsim 1 can be achieved. This condition can be satisfied by atmospheric neutrinos since they have a large range of energies and baselines. In spite of this, we find that hierarchy determination in the \theta_{13}=0 limit with atmospheric neutrinos is not a realistic possibility, even in conjunction with an apparently synergistic beam experiment like T2K or NOvA. We discuss the reasons for this, and also in the process clarify the conditions that must be satisfied in general for hierarchy determination if \theta_{13} = 0.
[ { "created": "Thu, 14 May 2009 19:36:20 GMT", "version": "v1" }, { "created": "Thu, 13 Aug 2009 19:57:07 GMT", "version": "v2" } ]
2014-11-18
[ [ "Gandhi", "Raj", "" ], [ "Ghoshal", "Pomita", "" ], [ "Goswami", "Srubabati", "" ], [ "Sankar", "S Uma", "" ] ]
We examine the possibility of determining the neutrino mass hierarchy in the limit \theta_{13} = 0 using atmospheric neutrinos as the source. In this limit, in which \theta_{13} driven matter effects are absent, independent measurements of \Delta_{31} and \Delta_{32} can, in principle, lead to hierarchy determination. Since the difference between these two is \Delta_{21}, one needs an experimental arrangement where \Delta_{21} L/E \gtrsim 1 can be achieved. This condition can be satisfied by atmospheric neutrinos since they have a large range of energies and baselines. In spite of this, we find that hierarchy determination in the \theta_{13}=0 limit with atmospheric neutrinos is not a realistic possibility, even in conjunction with an apparently synergistic beam experiment like T2K or NOvA. We discuss the reasons for this, and also in the process clarify the conditions that must be satisfied in general for hierarchy determination if \theta_{13} = 0.
hep-ph/9310226
null
Kari Enqvist
Aspects of Neutrino Cosmology
16 pages, TEX, (2 figures available upon request). NORDITA-93/65 P
null
null
null
hep-ph
null
Primordial nucleosynthesis constrains the properties of light, stable neutrinos. Apart from the well--known limit on the number of neutrino species, there are also bounds on neutrino masses and magnetic moments. I discuss also sterile neutrinos and neutrino propagation in a primordial magnetic field, such as could be the origin of the observed galactic magnetic fields.
[ { "created": "Tue, 5 Oct 1993 10:06:06 GMT", "version": "v1" } ]
2007-05-23
[ [ "Enqvist", "Kari", "" ] ]
Primordial nucleosynthesis constrains the properties of light, stable neutrinos. Apart from the well--known limit on the number of neutrino species, there are also bounds on neutrino masses and magnetic moments. I discuss also sterile neutrinos and neutrino propagation in a primordial magnetic field, such as could be the origin of the observed galactic magnetic fields.
hep-ph/9302260
Jihn E. Kim
Hang Bae Kim and Jihn E. Kim
Coupling Constant Unification and LEP Data
11 pages plus 4 figures, Figures can be sent by FAX upon request, Latex
J.Korean Phys.Soc. 27 (1994) 129-133
null
null
hep-ph
null
The recent LEP data for gauge coupling constants constrain many grand unified models. In this paper, we study several possibilities for unification of gauge coupling constants. Without an intermediate mass scale, the minimal supersymmetric standard model is the only possibility. For one intermediate mass scale, it is possible to have many routes toward grand unification: $SO(10)\rightarrow SU(3)_c\times SU(2)_L\times SU(2)_R\times U(1) , SU(7), SU(8)$, etc. We present also simple relations for the possibility of unification.
[ { "created": "Mon, 15 Feb 1993 11:20:29 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kim", "Hang Bae", "" ], [ "Kim", "Jihn E.", "" ] ]
The recent LEP data for gauge coupling constants constrain many grand unified models. In this paper, we study several possibilities for unification of gauge coupling constants. Without an intermediate mass scale, the minimal supersymmetric standard model is the only possibility. For one intermediate mass scale, it is possible to have many routes toward grand unification: $SO(10)\rightarrow SU(3)_c\times SU(2)_L\times SU(2)_R\times U(1) , SU(7), SU(8)$, etc. We present also simple relations for the possibility of unification.
hep-ph/9603227
Mariano Quiros
J.A. Casas, J.R. Espinosa and M. Quiros
Standard Model stability bounds for new physics within LHC reach
17 pages, latex + psfig.sty, 4 figures
Phys.Lett. B382 (1996) 374-382
10.1016/0370-2693(96)00682-X
SCIPP-96-04, DESY 96-021, IEM-FT-123/96
hep-ph
null
We analyse the stability lower bounds on the Standard Model Higgs mass by carefully controlling the scale independence of the effective potential. We include resummed leading and next-to-leading-log corrections, and physical pole masses for the Higgs boson, M_H, and the top-quark, M_t. Particular attention is devoted to the cases where the scale of new physics \Lambda is within LHC reach, i.e. \Lambda\leq 10 TeV, which have been the object of recent controversial results. We clarify the origin of discrepancies and confirm our earlier results within the error of our previous estimate. In particular for \Lambda=1 TeV we find that M_H[GeV]>52+0.64(M_t[GeV]-175)-0.50\frac{\alpha_s(M_Z)-0.118}{0.006}. For fixed values of M_t and \alpha_s(M_Z), the error from higher effects, as the lack of exact scale invariance of the effective potential and higher-order radiative corrections, is conservatively estimated to be \simlt 5 GeV.
[ { "created": "Tue, 5 Mar 1996 14:02:37 GMT", "version": "v1" } ]
2016-09-01
[ [ "Casas", "J. A.", "" ], [ "Espinosa", "J. R.", "" ], [ "Quiros", "M.", "" ] ]
We analyse the stability lower bounds on the Standard Model Higgs mass by carefully controlling the scale independence of the effective potential. We include resummed leading and next-to-leading-log corrections, and physical pole masses for the Higgs boson, M_H, and the top-quark, M_t. Particular attention is devoted to the cases where the scale of new physics \Lambda is within LHC reach, i.e. \Lambda\leq 10 TeV, which have been the object of recent controversial results. We clarify the origin of discrepancies and confirm our earlier results within the error of our previous estimate. In particular for \Lambda=1 TeV we find that M_H[GeV]>52+0.64(M_t[GeV]-175)-0.50\frac{\alpha_s(M_Z)-0.118}{0.006}. For fixed values of M_t and \alpha_s(M_Z), the error from higher effects, as the lack of exact scale invariance of the effective potential and higher-order radiative corrections, is conservatively estimated to be \simlt 5 GeV.
1405.7031
Markus Hopfer
Markus Hopfer, Christian S. Fischer, Reinhard Alkofer
Running coupling in the conformal window of large-Nf QCD
22 pages, 10 figures, additional clarifications and a reference added, version accepted by JHEP
null
10.1007/JHEP11(2014)035
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Quantum Chromodynamics with a relatively large number of fundamentally charged quark flavours in the chiral limit is considered. A self-consistent solution of the quark, gluon and ghost propagator Dyson-Schwinger equations in Landau gauge exhibits a phase transition. Above the critical number of fermion flavours the non-perturbative running coupling develops a plateau over a wide momentum range, and the propagators follow a power law behaviour for these momenta. Hereby, the critical number of quark flavours depends crucially on the beyond-tree-level tensor structures of the quark-gluon vertex.
[ { "created": "Tue, 27 May 2014 19:50:24 GMT", "version": "v1" }, { "created": "Wed, 1 Oct 2014 11:44:03 GMT", "version": "v2" } ]
2015-06-19
[ [ "Hopfer", "Markus", "" ], [ "Fischer", "Christian S.", "" ], [ "Alkofer", "Reinhard", "" ] ]
Quantum Chromodynamics with a relatively large number of fundamentally charged quark flavours in the chiral limit is considered. A self-consistent solution of the quark, gluon and ghost propagator Dyson-Schwinger equations in Landau gauge exhibits a phase transition. Above the critical number of fermion flavours the non-perturbative running coupling develops a plateau over a wide momentum range, and the propagators follow a power law behaviour for these momenta. Hereby, the critical number of quark flavours depends crucially on the beyond-tree-level tensor structures of the quark-gluon vertex.
hep-ph/0410316
Hai-Yang Cheng
Hai-Yang Cheng
Parity-even and Parity-odd Mesons in Covariant Light-front Approach
3 pages, talk given at the 2004 DPF Meeting, Riverside, CA. Aug 26-31, 2004
Int.J.Mod.Phys. A20 (2005) 3648-3650
10.1142/S0217751X05027199
null
hep-ph
null
Decay constants and form factors for parity-even (s-wave) and parity-odd (p-wave) mesons are studied within a covariant light-front approach. The three universal Isgur-Wise functions for heavy-to-heavy meson transitions are obtained.
[ { "created": "Sat, 23 Oct 2004 06:35:17 GMT", "version": "v1" } ]
2009-11-10
[ [ "Cheng", "Hai-Yang", "" ] ]
Decay constants and form factors for parity-even (s-wave) and parity-odd (p-wave) mesons are studied within a covariant light-front approach. The three universal Isgur-Wise functions for heavy-to-heavy meson transitions are obtained.
1510.02739
Bijan Chokoufe Nejad
B. Chokoufe Nejad, W. Kilian, J. Reuter, C. Weiss
Matching NLO QCD Corrections in WHIZARD with the POWHEG scheme
7 pages, 4 figures, to appear in the proceedings of the European Physical Society Conference on High Energy Physics 2015 (EPS-HEP 2015), Vienna, Austria, 22nd to 29th of July 2015
PoS(EPS-HEP2015)317
null
DESY 15-174, SI-HEP-2015-21
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Building on the new automatic subtraction of NLO amplitudes in WHIZARD, we present our implementation of the POWHEG scheme to match radiative corrections consistently with the parton shower. We apply this general framework to two linear collider processes, $e^+e^-\,\to\,t\bar{t}$ and $e^+e^-\,\to\,t\bar{t}H$.
[ { "created": "Fri, 9 Oct 2015 17:03:38 GMT", "version": "v1" } ]
2015-10-13
[ [ "Nejad", "B. Chokoufe", "" ], [ "Kilian", "W.", "" ], [ "Reuter", "J.", "" ], [ "Weiss", "C.", "" ] ]
Building on the new automatic subtraction of NLO amplitudes in WHIZARD, we present our implementation of the POWHEG scheme to match radiative corrections consistently with the parton shower. We apply this general framework to two linear collider processes, $e^+e^-\,\to\,t\bar{t}$ and $e^+e^-\,\to\,t\bar{t}H$.
hep-ph/0701232
Hanqing Zheng
Z. H. Guo, J. J. Sanz Cillero, H. Q. Zheng
Partial waves and large $N_C$ resonance sum rules
discussions expanded, reference added, version to be published in JHEP
JHEP 0706:030,2007
10.1088/1126-6708/2007/06/030
null
hep-ph
null
Using $1/N_C$ expansion and dispersion theory techniques, without relying on any explicit resonance lagrangian, we generalize the KSRF relation beyond the leading chiral order. Two sum rules for the low energy constants $L_2$, $L_3$ and a new relation between resonance couplings are derived. A rather detailed examination to the new relation is also given.
[ { "created": "Sat, 27 Jan 2007 10:12:56 GMT", "version": "v1" }, { "created": "Mon, 11 Jun 2007 02:33:31 GMT", "version": "v2" } ]
2010-10-27
[ [ "Guo", "Z. H.", "" ], [ "Cillero", "J. J. Sanz", "" ], [ "Zheng", "H. Q.", "" ] ]
Using $1/N_C$ expansion and dispersion theory techniques, without relying on any explicit resonance lagrangian, we generalize the KSRF relation beyond the leading chiral order. Two sum rules for the low energy constants $L_2$, $L_3$ and a new relation between resonance couplings are derived. A rather detailed examination to the new relation is also given.
hep-ph/0410026
Louis J. Clavelli
L. Clavelli
A supersymmetric origin of gamma ray bursts
9 pages, talk presented at Pascos04, Northeastern University, August 04, to be published by World Scientific Press. corrected citation in v2
null
null
UAHEP043
hep-ph astro-ph
null
Bright bursts of gamma rays from outer space have been puzzling Astronomers for more than thirty years and there is still no conceptually complete model for the phenomenon within the standard model of particle physics. Is it time to consider a supersymmetric (SUSY) origin for these bursts to add to the astronomical indications of supersymmetry from dark matter?
[ { "created": "Fri, 1 Oct 2004 21:50:54 GMT", "version": "v1" }, { "created": "Mon, 4 Oct 2004 20:48:26 GMT", "version": "v2" } ]
2007-05-23
[ [ "Clavelli", "L.", "" ] ]
Bright bursts of gamma rays from outer space have been puzzling Astronomers for more than thirty years and there is still no conceptually complete model for the phenomenon within the standard model of particle physics. Is it time to consider a supersymmetric (SUSY) origin for these bursts to add to the astronomical indications of supersymmetry from dark matter?
1304.4251
Ted Rogers
Ted C. Rogers
Extra Spin Asymmetries From the Breakdown of TMD-Factorization in Hadron-Hadron Collisions
46 pages, 9 figures
null
10.1103/PhysRevD.88.014002
null
hep-ph hep-ex nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We demonstrate that partonic correlations that would traditionally be identified as subleading on the basis of a generalized TMD-factorization conjecture can become leading-power because of TMD-factorization breaking that arises in hadron-hadron collisions with large transverse momentum back-to-back hadrons produced in the final state. General forms of TMD-factorization fail for such processes because of a previously noted incompatibility between the requirements for TMD-factorization and the Ward identities of non-Abelian gauge theories. We first review the basic steps for factorizing the gluon distribution and then show that a conflict between TMD-factorization and the non-Abelian Ward identity arises already at the level of a single extra soft or collinear gluon when the partonic subprocess involves a TMD gluon distribution. Next we show that the resulting TMD-factorization violating effects produce leading-power final state spin asymmetries that would be classified as subleading in a generalized TMD-factorization framework. We argue that similar extra TMD-factorization breaking effects may be necessary to explain a range of open phenomenological QCD puzzles. The potential to observe extra transverse spin or azimuthal asymmetries in future experiments is highlighted as their discovery may indicate an influence from novel and unexpected large distance parton correlations.
[ { "created": "Mon, 15 Apr 2013 20:06:04 GMT", "version": "v1" } ]
2013-08-09
[ [ "Rogers", "Ted C.", "" ] ]
We demonstrate that partonic correlations that would traditionally be identified as subleading on the basis of a generalized TMD-factorization conjecture can become leading-power because of TMD-factorization breaking that arises in hadron-hadron collisions with large transverse momentum back-to-back hadrons produced in the final state. General forms of TMD-factorization fail for such processes because of a previously noted incompatibility between the requirements for TMD-factorization and the Ward identities of non-Abelian gauge theories. We first review the basic steps for factorizing the gluon distribution and then show that a conflict between TMD-factorization and the non-Abelian Ward identity arises already at the level of a single extra soft or collinear gluon when the partonic subprocess involves a TMD gluon distribution. Next we show that the resulting TMD-factorization violating effects produce leading-power final state spin asymmetries that would be classified as subleading in a generalized TMD-factorization framework. We argue that similar extra TMD-factorization breaking effects may be necessary to explain a range of open phenomenological QCD puzzles. The potential to observe extra transverse spin or azimuthal asymmetries in future experiments is highlighted as their discovery may indicate an influence from novel and unexpected large distance parton correlations.
1007.1223
York Schroder
Jan Moeller, York Schroder
Open problems in hot QCD
6 pages; Talk presented at 10th DESY Workshop on Elementary Particle Theory: Loops and Legs in Quantum Field Theory, Worlitz, Germany, 25-30 April 2010
Nucl.Phys.Proc.Suppl.205-206:218-223,2010
10.1016/j.nuclphysbps.2010.08.046
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We try to give a comprehensive review of the main methods used in modern multi-loop calculations in finite-temperature field theory. While going through explicit examples, we point out similarities and differences with respect to the zero-temperature case, utilizing common techniques in a transparent way whenever possible.
[ { "created": "Wed, 7 Jul 2010 19:02:54 GMT", "version": "v1" } ]
2010-12-13
[ [ "Moeller", "Jan", "" ], [ "Schroder", "York", "" ] ]
We try to give a comprehensive review of the main methods used in modern multi-loop calculations in finite-temperature field theory. While going through explicit examples, we point out similarities and differences with respect to the zero-temperature case, utilizing common techniques in a transparent way whenever possible.
hep-ph/0702026
Massimo Passera
S. Eidelman, M. Giacomini, F.V. Ignatov and M. Passera
The tau lepton anomalous magnetic moment
6 pages. To appear in the proceedings of the Tau06 Workshop, Pisa, Italy, September 19-22 2006
Nucl.Phys.Proc.Suppl.169:226-231,2007
10.1016/j.nuclphysbps.2007.03.002
null
hep-ph
null
We review the Standard Model prediction of the tau lepton g-2 presenting updated QED and electroweak contributions, as well as recent determinations of the leading-order hadronic term, based on the low energy e+e- data, and of the hadronic light-by-light one.
[ { "created": "Fri, 2 Feb 2007 14:16:26 GMT", "version": "v1" } ]
2008-11-26
[ [ "Eidelman", "S.", "" ], [ "Giacomini", "M.", "" ], [ "Ignatov", "F. V.", "" ], [ "Passera", "M.", "" ] ]
We review the Standard Model prediction of the tau lepton g-2 presenting updated QED and electroweak contributions, as well as recent determinations of the leading-order hadronic term, based on the low energy e+e- data, and of the hadronic light-by-light one.
hep-ph/0306171
Veronica Sanz
Shaaban Khalil and Veronica Sanz
Can the CKM phase be the only source of CP violation?
10 pages, 4 figures. Replaced by the published version. Minor changes, references added
Phys.Lett. B576 (2003) 107-114
10.1016/j.physletb.2003.09.088
IPPP/03/36;DCPT/03/72
hep-ph
null
We address the question of whether the CP violating phase in the CKM mixing matrix can be the only source of all CP violation. We show that in supersymmetric models with new flavour structure beyond the Yukawa matrices, the CKM phase can generate the required baryon asymmetry and also accounts for all observed results in K and B systems, in particular $\epsilon'/\epsilon$ and the CP asymmetry of $B \to \phi K_S$.
[ { "created": "Wed, 18 Jun 2003 18:45:39 GMT", "version": "v1" }, { "created": "Fri, 14 Nov 2003 12:19:00 GMT", "version": "v2" } ]
2015-06-25
[ [ "Khalil", "Shaaban", "" ], [ "Sanz", "Veronica", "" ] ]
We address the question of whether the CP violating phase in the CKM mixing matrix can be the only source of all CP violation. We show that in supersymmetric models with new flavour structure beyond the Yukawa matrices, the CKM phase can generate the required baryon asymmetry and also accounts for all observed results in K and B systems, in particular $\epsilon'/\epsilon$ and the CP asymmetry of $B \to \phi K_S$.
hep-ph/0110249
Piotr Chankowski
P.H. Chankowski and S. Pokorski (IFT, Warsaw Univ.)
Quantum corrections to neutrino masses and mixing angles
To appear in the review section of Modern Physics A. 44 pages, no postscript figures
Int.J.Mod.Phys.A17:575-614,2002
10.1142/S0217751X02006109
IFT-01/27
hep-ph
null
Contents: 1. Introduction 2. Fermion masses and mixing 3. Neutrino masses in the effective theory 4. Quantum corrections from the renormalization group evolution 4.1. RG equations for the CKM matrix 4.2. RG equations for neutrino masses and mixing angles 4.3. Evolution of the neutrino masses 4.4. Mixing of two neutrinos 4.5 Mixing of three neutrinos and fixed points 5. Low energy threshold corrections 5.1. Threshold corrections in the SM 5.2. Threshold corrections in the MSSM 5.2.1. Three-fold degeneracy and flavour diagonal corrections 5.2.2. Three-fold degeneracy and flavour non-diagonal corrections 5.2.3. Two-fold degeneracy and threshold corrections 6. Conclusions, Appendix A, Appendix B, References.
[ { "created": "Thu, 18 Oct 2001 09:46:44 GMT", "version": "v1" } ]
2008-11-26
[ [ "Chankowski", "P. H.", "", "IFT, Warsaw Univ." ], [ "Pokorski", "S.", "", "IFT, Warsaw Univ." ] ]
Contents: 1. Introduction 2. Fermion masses and mixing 3. Neutrino masses in the effective theory 4. Quantum corrections from the renormalization group evolution 4.1. RG equations for the CKM matrix 4.2. RG equations for neutrino masses and mixing angles 4.3. Evolution of the neutrino masses 4.4. Mixing of two neutrinos 4.5 Mixing of three neutrinos and fixed points 5. Low energy threshold corrections 5.1. Threshold corrections in the SM 5.2. Threshold corrections in the MSSM 5.2.1. Three-fold degeneracy and flavour diagonal corrections 5.2.2. Three-fold degeneracy and flavour non-diagonal corrections 5.2.3. Two-fold degeneracy and threshold corrections 6. Conclusions, Appendix A, Appendix B, References.
hep-ph/9807353
Ferruccio Feruglio
Guido Altarelli and Ferruccio Feruglio
Neutrino Mass Textures from Oscillations with Maximal Mixing
8 pages, LaTeX; a new model discussed in sec. 3, references added
Phys.Lett. B439 (1998) 112-118
10.1016/S0370-2693(98)01007-7
CERN-TH.98-226, DFPD-98/TH-34
hep-ph
null
We study the implications of neutrino oscillations with maximal mixing for the neutrino Dirac and Majorana matrices in the see-saw mechanism for three non degenerate neutrino masses. We find the form of the Dirac matrix for a structure-less Majorana matrix and, conversely, the structure of the Majorana matrix if the Dirac matrix is according to our naive intuition. We give some examples of Majorana matrices that, in a 3 X 3 context, lead to maximal mixing without too much fine tuning and cross talk with the Dirac input.
[ { "created": "Mon, 13 Jul 1998 12:56:44 GMT", "version": "v1" }, { "created": "Mon, 20 Jul 1998 13:20:27 GMT", "version": "v2" } ]
2009-10-31
[ [ "Altarelli", "Guido", "" ], [ "Feruglio", "Ferruccio", "" ] ]
We study the implications of neutrino oscillations with maximal mixing for the neutrino Dirac and Majorana matrices in the see-saw mechanism for three non degenerate neutrino masses. We find the form of the Dirac matrix for a structure-less Majorana matrix and, conversely, the structure of the Majorana matrix if the Dirac matrix is according to our naive intuition. We give some examples of Majorana matrices that, in a 3 X 3 context, lead to maximal mixing without too much fine tuning and cross talk with the Dirac input.
hep-ph/0012244
Jungil Lee
Eric Braaten (OSU) and Jungil Lee (DESY)
Polarization of Upsilon(nS) at the Tevatron
15 pages, 3 figures
Phys.Rev.D63:071501,2001
10.1103/PhysRevD.63.071501
DESY 00-185
hep-ph
null
The polarization of inclusive Upsilon(nS) at the Fermilab Tevatron is calculated within the nonrelativistic QCD factorization framework. We use a recent determination of the NRQCD matrix elements from fitting the CDF data on bottomonium production from Run IB of the Tevatron. The result for the polarization of Upsilon(1S) integrated over the transverse momentum bin 8 < p_T < 20 GeV is consistent with a recent measurement by the CDF Collaboration. The transverse polarization of Upsilon(1S) is predicted to increase steadily for p_T greater than about 10 GeV. The Upsilon(2S) and Upsilon(3S) are predicted to have significantly larger transverse polarizations than Upsilon(1S).
[ { "created": "Tue, 19 Dec 2000 13:32:09 GMT", "version": "v1" } ]
2009-12-31
[ [ "Braaten", "Eric", "", "OSU" ], [ "Lee", "Jungil", "", "DESY" ] ]
The polarization of inclusive Upsilon(nS) at the Fermilab Tevatron is calculated within the nonrelativistic QCD factorization framework. We use a recent determination of the NRQCD matrix elements from fitting the CDF data on bottomonium production from Run IB of the Tevatron. The result for the polarization of Upsilon(1S) integrated over the transverse momentum bin 8 < p_T < 20 GeV is consistent with a recent measurement by the CDF Collaboration. The transverse polarization of Upsilon(1S) is predicted to increase steadily for p_T greater than about 10 GeV. The Upsilon(2S) and Upsilon(3S) are predicted to have significantly larger transverse polarizations than Upsilon(1S).
hep-ph/0501016
Zhang He
Zhi-zhong Xing, He Zhang
Model-independent Constraints on the Weak Phase $\alpha$ (or $\phi_2$) and QCD Penguin Pollution in $B \to \pi\pi$ Decays
11 pages, 3 figures, 2 tables
Phys.Rev. D71 (2005) 051302
10.1103/PhysRevD.71.051302
null
hep-ph hep-ex
null
We present an {\it algebraic} isospin approach towards a more straightforward and model-independent determination of the weak phase $\alpha$ (or $\phi_2$) and QCD penguin pollution in $B\to \pi\pi$ decays. The world averages of current experimental data allow us to impose some useful constraints on the isospin parameters of $B\to \pi\pi$ transitions. We find that the magnitude of $\alpha$ (or $\phi_2$) extracted from the indirect CP violation in $\pi^+\pi^-$ mode is in agreement with the standard-model expectation from other indirect measurements, but its four-fold discrete ambiguity has to be resolved in the near future.
[ { "created": "Tue, 4 Jan 2005 05:25:58 GMT", "version": "v1" } ]
2009-11-11
[ [ "Xing", "Zhi-zhong", "" ], [ "Zhang", "He", "" ] ]
We present an {\it algebraic} isospin approach towards a more straightforward and model-independent determination of the weak phase $\alpha$ (or $\phi_2$) and QCD penguin pollution in $B\to \pi\pi$ decays. The world averages of current experimental data allow us to impose some useful constraints on the isospin parameters of $B\to \pi\pi$ transitions. We find that the magnitude of $\alpha$ (or $\phi_2$) extracted from the indirect CP violation in $\pi^+\pi^-$ mode is in agreement with the standard-model expectation from other indirect measurements, but its four-fold discrete ambiguity has to be resolved in the near future.
hep-ph/0008165
Debrupa Chakraverty
Debrupa Chakraverty and Debajyoti Choudhury
b --> s gamma confronts B-violating scalar couplings: R-parity violating supersymmetry or diquark
14 pages, latex
Phys.Rev.D63:075009,2001
10.1103/PhysRevD.63.075009
null
hep-ph
null
We investigate the possible role that baryon number violating Yukawa interactions may take in the inclusive decay $ B \to X_s \gamma$. The constraints, derived using the experimental results of the CLEO collaboration, turn out, in many cases, to be more stringent than the existing bounds.
[ { "created": "Wed, 16 Aug 2000 10:27:36 GMT", "version": "v1" } ]
2014-11-17
[ [ "Chakraverty", "Debrupa", "" ], [ "Choudhury", "Debajyoti", "" ] ]
We investigate the possible role that baryon number violating Yukawa interactions may take in the inclusive decay $ B \to X_s \gamma$. The constraints, derived using the experimental results of the CLEO collaboration, turn out, in many cases, to be more stringent than the existing bounds.
1803.07367
Antonio Enrique C\'arcamo Hern\'andez
A. E. C\'arcamo Hern\'andez, Stephen F. King
Muon anomalies and the $SU(5)$ Yukawa relations
38 pages, 3 figures. Published version
Phys. Rev. D 99, 095003 (2019)
10.1103/PhysRevD.99.095003
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that, within the framework of $SU(5)$ Grand Unified Theories (GUTs), multiple vector-like families at the GUT scale which transform under a gauged $U(1)'$ (under which the three chiral families are neutral) can result in a single vector-like family at low energies which can induce non-universal and flavourful $Z'$ couplings, which can account for the B physics anomalies in $R_{K^{(*)}}$. In such theories, we show that the same muon couplings which explain $R_{K^{(*)}}$ also correct the Yukawa relation $Y_e=Y_d^T$ in the muon sector without the need for higher Higgs representations. To illustrate the mechanism, we construct a concrete a model based on $SU(5)\times A_4 \times Z_3\times Z_7$ with two vector-like families at the GUT scale, and two right-handed neutrinos, leading to a successful fit to quark and lepton (including neutrino) masses, mixing angles and CP phases, where the constraints from lepton flavour violation require $Y_e$ to be diagonal.
[ { "created": "Tue, 20 Mar 2018 11:12:09 GMT", "version": "v1" }, { "created": "Mon, 7 Jan 2019 16:58:11 GMT", "version": "v2" }, { "created": "Sun, 12 May 2019 17:18:19 GMT", "version": "v3" } ]
2019-05-14
[ [ "Hernández", "A. E. Cárcamo", "" ], [ "King", "Stephen F.", "" ] ]
We show that, within the framework of $SU(5)$ Grand Unified Theories (GUTs), multiple vector-like families at the GUT scale which transform under a gauged $U(1)'$ (under which the three chiral families are neutral) can result in a single vector-like family at low energies which can induce non-universal and flavourful $Z'$ couplings, which can account for the B physics anomalies in $R_{K^{(*)}}$. In such theories, we show that the same muon couplings which explain $R_{K^{(*)}}$ also correct the Yukawa relation $Y_e=Y_d^T$ in the muon sector without the need for higher Higgs representations. To illustrate the mechanism, we construct a concrete a model based on $SU(5)\times A_4 \times Z_3\times Z_7$ with two vector-like families at the GUT scale, and two right-handed neutrinos, leading to a successful fit to quark and lepton (including neutrino) masses, mixing angles and CP phases, where the constraints from lepton flavour violation require $Y_e$ to be diagonal.
hep-ph/0403113
Alexander Kryukov
E. Boos, V. Bunichev, M. Dubinin, L. Dudko, V. Ilyin, A. Kryukov, V. Edneral, V. Savrin, A. Semenov, A. Sherstnev (the CompHEP collaboration)
CompHEP 4.4 - Automatic Computations from Lagrangians to Events
The paper has been presented on IX International Workshop on Advanced Computing and Analysis Techniques in Physics Research December 1-5, 2003. KEK, Japan. 10 pages, 2 figures
Nucl.Instrum.Meth.A534:250-259,2004
10.1016/j.nima.2004.07.096
null
hep-ph
null
We present a new version of the CompHEP program (version 4.4). We describe shortly new issues implemented in this version, namely, simplification of quark flavor combinatorics for the evaluation of hadronic processes, Les Houches Accord based CompHEP-PYTHIA interface, processing the color configurations of events, implementation of MSSM, symbolical and numerical batch modes, etc. We discuss how the CompHEP program is used for preparing event generators for various physical processes. We mention a few concrete physics examples for CompHEP based generators prepared for the LHC and Tevatron.
[ { "created": "Wed, 10 Mar 2004 15:48:19 GMT", "version": "v1" } ]
2008-11-26
[ [ "Boos", "E.", "", "the CompHEP collaboration" ], [ "Bunichev", "V.", "", "the CompHEP collaboration" ], [ "Dubinin", "M.", "", "the CompHEP collaboration" ], [ "Dudko", "L.", "", "the CompHEP collaboration" ], [ "Ilyin", "V.", "", "the CompHEP collaboration" ], [ "Kryukov", "A.", "", "the CompHEP collaboration" ], [ "Edneral", "V.", "", "the CompHEP collaboration" ], [ "Savrin", "V.", "", "the CompHEP collaboration" ], [ "Semenov", "A.", "", "the CompHEP collaboration" ], [ "Sherstnev", "A.", "", "the CompHEP collaboration" ] ]
We present a new version of the CompHEP program (version 4.4). We describe shortly new issues implemented in this version, namely, simplification of quark flavor combinatorics for the evaluation of hadronic processes, Les Houches Accord based CompHEP-PYTHIA interface, processing the color configurations of events, implementation of MSSM, symbolical and numerical batch modes, etc. We discuss how the CompHEP program is used for preparing event generators for various physical processes. We mention a few concrete physics examples for CompHEP based generators prepared for the LHC and Tevatron.
2311.04087
Ashutosh Alok
Ashutosh Kumar Alok, Trambak Jyoti Chall, Neetu Raj Singh Chundawat, Arindam Mandal
Spin-Flavor Oscillations of Relic Neutrinos in Primordial Magnetic Field
11 pages, 2 figures; matches accepted version in Phys. Rev. D
Phys. Rev. D 109, 055011 (2024)
10.1103/PhysRevD.109.055011
null
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by-sa/4.0/
The neutrino magnetic moment operator clasps a tiny but non-zero value within the standard model (SM) of particle physics and rather enhanced values in various new physics models. This generation of the magnetic moment ($\mu_\nu$) is through quantum loop corrections which can exhibit spin-flavor oscillations in the presence of an external magnetic field. Also, several studies predict the existence of a primordial magnetic field (PMF) in the early universe, extending back to the era of Big Bang Nucleosynthesis (BBN) and before. The recent NANOGrav measurement can be considered as a strong indication of the presence of these PMFs. In this work, we consider the effect of the PMF on the flux of relic neutrinos. For Dirac neutrinos, we show that half of the active relic neutrinos can become sterile due to spin-flavor oscillations well before becoming non-relativistic owing to the expansion of the Universe and also before the timeline of the formation of galaxies and hence intergalactic fields, subject to the constraints on the combined value of $\mu_\nu$ and the cosmic magnetic field at the time of neutrino decoupling. For the upper limit of PMF allowed by the BBN, this can be true even if the experimental bounds on $\mu_{\nu}$ approaches a few times its SM value.
[ { "created": "Tue, 7 Nov 2023 15:55:47 GMT", "version": "v1" }, { "created": "Tue, 27 Feb 2024 07:08:50 GMT", "version": "v2" } ]
2024-03-12
[ [ "Alok", "Ashutosh Kumar", "" ], [ "Chall", "Trambak Jyoti", "" ], [ "Chundawat", "Neetu Raj Singh", "" ], [ "Mandal", "Arindam", "" ] ]
The neutrino magnetic moment operator clasps a tiny but non-zero value within the standard model (SM) of particle physics and rather enhanced values in various new physics models. This generation of the magnetic moment ($\mu_\nu$) is through quantum loop corrections which can exhibit spin-flavor oscillations in the presence of an external magnetic field. Also, several studies predict the existence of a primordial magnetic field (PMF) in the early universe, extending back to the era of Big Bang Nucleosynthesis (BBN) and before. The recent NANOGrav measurement can be considered as a strong indication of the presence of these PMFs. In this work, we consider the effect of the PMF on the flux of relic neutrinos. For Dirac neutrinos, we show that half of the active relic neutrinos can become sterile due to spin-flavor oscillations well before becoming non-relativistic owing to the expansion of the Universe and also before the timeline of the formation of galaxies and hence intergalactic fields, subject to the constraints on the combined value of $\mu_\nu$ and the cosmic magnetic field at the time of neutrino decoupling. For the upper limit of PMF allowed by the BBN, this can be true even if the experimental bounds on $\mu_{\nu}$ approaches a few times its SM value.
2107.12611
Arnab Chaudhuri
Arnab Chaudhuri and Maxim Yu. Khlopov
Balancing Asymmetric Dark Matter with Baryon Asymmetry by Sphaleron Transitions
Presented at the 1st Electronic Conference on Universe, {22--28 February} 2021; Available online: https://ecu2021.sciforum.net
Phys. Sci. Forum 2021, 2(1), 41
10.3390/ECU2021-09269
null
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
The effect of the electroweak sphaleron transition in balance between baryon excess and and the excess of stable quarks of 4th generation is studied in this paper. Considering the non-violation of $SU(2)$ symmetry and the conservation of electroweak and new charges and quantum numbers of the new family, it makes possible sphaleron transitions between baryons, leptons and 4th family of leptons and quarks. In this paper, we have tried to established a possible definite relationship between the value and sign of the 4th family excess relative to baryon asymmetry. If $U$-type quarks are the lightest quarks of the 4th family and sphaleron transitions provide excessive $\bar U$ antiquarks, asymmetric dark matter in the form of dark atom bound state of ($\bar{U} \bar{U} \bar{U}$) with primordial He nuclei is balanced with baryon asymmetry.
[ { "created": "Tue, 27 Jul 2021 05:47:56 GMT", "version": "v1" } ]
2021-07-28
[ [ "Chaudhuri", "Arnab", "" ], [ "Khlopov", "Maxim Yu.", "" ] ]
The effect of the electroweak sphaleron transition in balance between baryon excess and and the excess of stable quarks of 4th generation is studied in this paper. Considering the non-violation of $SU(2)$ symmetry and the conservation of electroweak and new charges and quantum numbers of the new family, it makes possible sphaleron transitions between baryons, leptons and 4th family of leptons and quarks. In this paper, we have tried to established a possible definite relationship between the value and sign of the 4th family excess relative to baryon asymmetry. If $U$-type quarks are the lightest quarks of the 4th family and sphaleron transitions provide excessive $\bar U$ antiquarks, asymmetric dark matter in the form of dark atom bound state of ($\bar{U} \bar{U} \bar{U}$) with primordial He nuclei is balanced with baryon asymmetry.
1411.2004
Jozef Dudek
David J. Wilson, Jozef J. Dudek, Robert G. Edwards, Christopher E. Thomas
Resonances in coupled $\pi K, \eta K$ scattering from lattice QCD
32 pages, 27 figures - replaced to better match version appearing in PRD. Previously incorrect JLab preprint number also corrected
Phys. Rev. D 91, 054008 (2015)
10.1103/PhysRevD.91.054008
JLAB-THY-14-1892, DAMTP-2014-81
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Coupled-channel $\pi K$ and $\eta K$ scattering amplitudes are determined by studying the finite-volume energy spectra obtained from dynamical lattice QCD calculations. Using a large basis of interpolating operators, including both those resembling a $q\bar{q}$ construction and those resembling a pair of mesons with relative momentum, a reliable excited-state spectrum can be obtained. Working at ${m_\pi=391\,\mathrm{MeV}}$, we find a gradual increase in the $J^P=0^+$ $\pi K$ phase-shift which may be identified with a broad scalar resonance that couples strongly to $\pi K$ and weakly to $\eta K$. The low-energy behavior of this amplitude suggests a virtual bound-state that may be related to the $\kappa$ resonance. A bound state with $J^P=1^-$ is found very close to the $\pi K$ threshold energy, whose coupling to the $\pi K$ channel is compatible with that of the experimental $K^\star(892)$. Evidence is found for a narrow resonance in $J^P=2^+$. Isospin--3/2 $\pi K$ scattering is also studied and non-resonant phase-shifts spanning the whole elastic scattering region are obtained.
[ { "created": "Fri, 7 Nov 2014 19:01:00 GMT", "version": "v1" }, { "created": "Wed, 11 Mar 2015 15:33:58 GMT", "version": "v2" } ]
2015-03-18
[ [ "Wilson", "David J.", "" ], [ "Dudek", "Jozef J.", "" ], [ "Edwards", "Robert G.", "" ], [ "Thomas", "Christopher E.", "" ] ]
Coupled-channel $\pi K$ and $\eta K$ scattering amplitudes are determined by studying the finite-volume energy spectra obtained from dynamical lattice QCD calculations. Using a large basis of interpolating operators, including both those resembling a $q\bar{q}$ construction and those resembling a pair of mesons with relative momentum, a reliable excited-state spectrum can be obtained. Working at ${m_\pi=391\,\mathrm{MeV}}$, we find a gradual increase in the $J^P=0^+$ $\pi K$ phase-shift which may be identified with a broad scalar resonance that couples strongly to $\pi K$ and weakly to $\eta K$. The low-energy behavior of this amplitude suggests a virtual bound-state that may be related to the $\kappa$ resonance. A bound state with $J^P=1^-$ is found very close to the $\pi K$ threshold energy, whose coupling to the $\pi K$ channel is compatible with that of the experimental $K^\star(892)$. Evidence is found for a narrow resonance in $J^P=2^+$. Isospin--3/2 $\pi K$ scattering is also studied and non-resonant phase-shifts spanning the whole elastic scattering region are obtained.
1610.09853
Kei Suzuki
Kei Suzuki and Su Houng Lee
Delayed versus accelerated quarkonium formation in a magnetic field
7 pages, 4 figures; published version
Phys. Rev. C 96, 035203 (2017)
10.1103/PhysRevC.96.035203
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Formation time of heavy quarkonia in a homogeneous magnetic field is analyzed by using a phenomenological ansatz of the vector current correlator. Because the existence of a magnetic field mixes vector quarkonia ($J/\psi$, $\psi^\prime$) and their pseudoscalar partners ($\eta_c$, $\eta_c^\prime$), the properties of the quarkonia can be modified through such a spin mixing. This means that the formation time of quarkonia is also changed by the magnetic field. We show the formation time of vector quarkonia is delayed by an idealized constant magnetic field, where the formation time of the excited state becomes longer than that of the ground state. As a more realistic situation in heavy-ion collisions, effects by a time-dependent magnetic field are also discussed, where delayed formation of $J/\psi$ and $\psi^\prime$ and very early formation of $\eta_c$ and $\eta_c^\prime$ are found.
[ { "created": "Mon, 31 Oct 2016 10:31:18 GMT", "version": "v1" }, { "created": "Sat, 9 Sep 2017 17:37:20 GMT", "version": "v2" } ]
2017-09-12
[ [ "Suzuki", "Kei", "" ], [ "Lee", "Su Houng", "" ] ]
Formation time of heavy quarkonia in a homogeneous magnetic field is analyzed by using a phenomenological ansatz of the vector current correlator. Because the existence of a magnetic field mixes vector quarkonia ($J/\psi$, $\psi^\prime$) and their pseudoscalar partners ($\eta_c$, $\eta_c^\prime$), the properties of the quarkonia can be modified through such a spin mixing. This means that the formation time of quarkonia is also changed by the magnetic field. We show the formation time of vector quarkonia is delayed by an idealized constant magnetic field, where the formation time of the excited state becomes longer than that of the ground state. As a more realistic situation in heavy-ion collisions, effects by a time-dependent magnetic field are also discussed, where delayed formation of $J/\psi$ and $\psi^\prime$ and very early formation of $\eta_c$ and $\eta_c^\prime$ are found.
hep-ph/9607427
Anselmino Mauro
M. Anselmino, P. Gambino and J. Kalinowski
New proton polarized structure functions in charged current processes at HERA
LaTeX, 8 pages, 6 figures
Phys.Rev. D55 (1997) 5841-5844
10.1103/PhysRevD.55.5841
DFTT 44/96, IFT-96-16, MPI-PhT/96-63
hep-ph
null
Estimates for longitudinal spin asymmetries which single out new polarized nucleon structure functions in deeply inelastic charged current interactions at HERA energies are given, exploiting their interpretation in terms of polarized quark distributions. These asymmetries turn out to be large and allow a measurement of the new polarized structure functions $g_1^{W}$ and $g_5^{W}$, which would add valuable tests and information on the spin content of quarks inside a polarized proton. We also show that single spin asymmetries in neutral current interactions are very small.
[ { "created": "Thu, 25 Jul 1996 11:17:19 GMT", "version": "v1" } ]
2009-10-28
[ [ "Anselmino", "M.", "" ], [ "Gambino", "P.", "" ], [ "Kalinowski", "J.", "" ] ]
Estimates for longitudinal spin asymmetries which single out new polarized nucleon structure functions in deeply inelastic charged current interactions at HERA energies are given, exploiting their interpretation in terms of polarized quark distributions. These asymmetries turn out to be large and allow a measurement of the new polarized structure functions $g_1^{W}$ and $g_5^{W}$, which would add valuable tests and information on the spin content of quarks inside a polarized proton. We also show that single spin asymmetries in neutral current interactions are very small.
0912.1625
Ulrich Haisch
M. Bauer (Mainz U.), S. Casagrande (TU Munich), U. Haisch (Mainz U.), and M. Neubert (Mainz U.)
Flavor Physics in the Randall-Sundrum Model: II. Tree-Level Weak-Interaction Processes
112 pages (sorry!), 22 figures; v2: Extended version of the JHEP publication
JHEP 1009:017,2010
10.1007/JHEP09(2010)017
MZ-TH/09-46
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A comprehensive analysis of tree-level weak interaction processes at low energy is presented for the Randall-Sundrum (RS) model with SU(2)_L * U(1)_Y bulk gauge symmetry and brane-localized Higgs sector. The complete form of the effective weak Hamiltonian is obtained, which results from tree-level exchange of Kaluza-Klein (KK) gluons and photons, the W^+- and Z^0 bosons and their KK excitations, as well as the Higgs boson. Exact expressions are used for the bulk profiles of the various fields, and for the exchange of entire towers of KK gauge-boson states. A detailed phenomenological analysis is performed for potential new-physics effects in neutral-meson mixing and in rare decays of kaons and B mesons, including both inclusive and exclusive processes. We find that while the predictions for \Delta(F)=2 observables are rather model-independent, \Delta(F)=1 processes depend sensitively on the exact realizations of the electroweak gauge and the fermionic sector. In this context, we emphasize that the localization of the right-handed top quark in the extra dimension plays a crucial role in the case of rare Z^0-mediated decays, as it determines the relative size of left- to right-handed couplings. We also extend earlier studies of quark flavor-changing neutral currents by examining observables which up to now attracted little attention. These include D-D(bar) mixing, B-->\tau\nu, B-->X_s (K^*) l^+ l^-, \epsilon_K'/\epsilon_K, B-->\pi K, B^0-->\phi K_S, B^0-->\eta' K_S, and B^+-->\pi^+\pi^0.
[ { "created": "Wed, 9 Dec 2009 14:40:06 GMT", "version": "v1" }, { "created": "Wed, 20 Oct 2010 07:52:13 GMT", "version": "v2" } ]
2010-10-21
[ [ "Bauer", "M.", "", "Mainz U." ], [ "Casagrande", "S.", "", "TU Munich" ], [ "Haisch", "U.", "", "Mainz U." ], [ "Neubert", "M.", "", "Mainz U." ] ]
A comprehensive analysis of tree-level weak interaction processes at low energy is presented for the Randall-Sundrum (RS) model with SU(2)_L * U(1)_Y bulk gauge symmetry and brane-localized Higgs sector. The complete form of the effective weak Hamiltonian is obtained, which results from tree-level exchange of Kaluza-Klein (KK) gluons and photons, the W^+- and Z^0 bosons and their KK excitations, as well as the Higgs boson. Exact expressions are used for the bulk profiles of the various fields, and for the exchange of entire towers of KK gauge-boson states. A detailed phenomenological analysis is performed for potential new-physics effects in neutral-meson mixing and in rare decays of kaons and B mesons, including both inclusive and exclusive processes. We find that while the predictions for \Delta(F)=2 observables are rather model-independent, \Delta(F)=1 processes depend sensitively on the exact realizations of the electroweak gauge and the fermionic sector. In this context, we emphasize that the localization of the right-handed top quark in the extra dimension plays a crucial role in the case of rare Z^0-mediated decays, as it determines the relative size of left- to right-handed couplings. We also extend earlier studies of quark flavor-changing neutral currents by examining observables which up to now attracted little attention. These include D-D(bar) mixing, B-->\tau\nu, B-->X_s (K^*) l^+ l^-, \epsilon_K'/\epsilon_K, B-->\pi K, B^0-->\phi K_S, B^0-->\eta' K_S, and B^+-->\pi^+\pi^0.
hep-ph/0109163
A. B. Balantekin
A.B. Balantekin (Wisconsin U., Madison)
Neutrinos in Stochastic Media: From Sun to Core-Collapse Supernovae
4 pages, to be published in the proceedings of the International Nuclear Physics Conference (INPC 2001): Nuclear Physics And The 21st Century, 30 Jul - 3 Aug 2001, Berkeley, California
AIPConf.Proc.610:969-972,2002
10.1063/1.1470265
null
hep-ph
null
Recent work on neutrino propagation in stochastic media and its implications for the Sun and core-collapse supernovae are reviewed. It is shown that recent results from Sudbury Neutrino Observatory and SuperKamiokande combined with a best global fit value of $\delta m^2= 5\times 10^{-5}$ eV$^2$ and $\tan^2 \theta = 0.3$ rule out solar electron density fluctuations of a few percent or more. It is argued that solar neutrino experiments may be able to rule out even smaller fluctuations in the near future.
[ { "created": "Tue, 18 Sep 2001 16:29:35 GMT", "version": "v1" } ]
2008-11-26
[ [ "Balantekin", "A. B.", "", "Wisconsin U., Madison" ] ]
Recent work on neutrino propagation in stochastic media and its implications for the Sun and core-collapse supernovae are reviewed. It is shown that recent results from Sudbury Neutrino Observatory and SuperKamiokande combined with a best global fit value of $\delta m^2= 5\times 10^{-5}$ eV$^2$ and $\tan^2 \theta = 0.3$ rule out solar electron density fluctuations of a few percent or more. It is argued that solar neutrino experiments may be able to rule out even smaller fluctuations in the near future.
hep-ph/9206242
Vicente Pleitez
F. Pisano and V. Pleitez
$SU(3)\otimes U(1)$ Model for Electroweak Interactions
22 pages, 4 figures (available from authors), preprint IFT-P.008/92 use revtex
Phys.Rev.D46:410-417,1992
10.1103/PhysRevD.46.410
null
hep-ph
null
We consider a gauge model based on $SU(3)\otimes U(1)$ symmetry in which the lepton number is violated explicitly by charged scalar and gauge bosons, including a vector field with double electric charge. Although there exist in the literature several models based on a $SU(3)\otimes U(1)$ gauge symmetry, our model has a different representation content and a quite different new physics at an, in principle, arbitrary mass scale. This is possibly the simplest way to enlarge the gauge group $SU_L(2)\otimes U_Y(1)$ in order to have doubly charged gauge bosons, without losing the natural features of the standard electroweak model. The price we must pay is the introduction of exotic quarks, with electric charge $5/3$ and $-4/3$. A previous version of the model was considered several months ago concerning the possibility that in this kind of models neutrinoless double beta decay proceeds even for massless neutrinos and with scalar exchange instead of vector exchange. Our work is in press in Physical Review D.
[ { "created": "Mon, 22 Jun 1992 20:47:26 GMT", "version": "v1" } ]
2009-07-28
[ [ "Pisano", "F.", "" ], [ "Pleitez", "V.", "" ] ]
We consider a gauge model based on $SU(3)\otimes U(1)$ symmetry in which the lepton number is violated explicitly by charged scalar and gauge bosons, including a vector field with double electric charge. Although there exist in the literature several models based on a $SU(3)\otimes U(1)$ gauge symmetry, our model has a different representation content and a quite different new physics at an, in principle, arbitrary mass scale. This is possibly the simplest way to enlarge the gauge group $SU_L(2)\otimes U_Y(1)$ in order to have doubly charged gauge bosons, without losing the natural features of the standard electroweak model. The price we must pay is the introduction of exotic quarks, with electric charge $5/3$ and $-4/3$. A previous version of the model was considered several months ago concerning the possibility that in this kind of models neutrinoless double beta decay proceeds even for massless neutrinos and with scalar exchange instead of vector exchange. Our work is in press in Physical Review D.
2107.05459
Roberto Bruschini M.S.
R. Bruschini and P. Gonz\'alez
Coupled-channel meson-meson scattering in the diabatic framework
15 pages, 3 figures; v2: extended bibliography, new paragraph in Introduction, corrected statement near end of Sec. II, additional minor modifications
Phys. Rev. D 104, 074025 (2021)
10.1103/PhysRevD.104.074025
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We apply the diabatic framework, a QCD-based formalism for the unified study of quarkoniumlike systems in terms of heavy quark-antiquark and open-flavor meson-meson components, to the description of coupled-channel meson-meson scattering. For this purpose, we first introduce a numerical scheme to find the solutions of the diabatic Schr\"odinger equation for energies in the continuum, then we derive a general formula for calculating the meson-meson scattering amplitudes from these solutions. We thus obtain a completely nonperturbative procedure for the calculation of open-flavor meson-meson scattering cross sections from the diabatic potential, which is directly connected to lattice QCD calculations. A comprehensive analysis of various elastic cross sections for open-charm and open-bottom meson-meson pairs is performed in a wide range of the center-of-mass energies. The relevant structures are identified, showing a spectrum of quasi-conventional and unconventional quarkoniumlike states. In addition to the customary Breit-Wigner peaks we obtain nontrivial structures such as threshold cusps and minimums. Finally, our results are compared with existing data and with results from our previous bound-state--based analysis, finding full compatibility with both.
[ { "created": "Mon, 12 Jul 2021 14:29:29 GMT", "version": "v1" }, { "created": "Mon, 13 Sep 2021 09:16:06 GMT", "version": "v2" } ]
2021-10-26
[ [ "Bruschini", "R.", "" ], [ "González", "P.", "" ] ]
We apply the diabatic framework, a QCD-based formalism for the unified study of quarkoniumlike systems in terms of heavy quark-antiquark and open-flavor meson-meson components, to the description of coupled-channel meson-meson scattering. For this purpose, we first introduce a numerical scheme to find the solutions of the diabatic Schr\"odinger equation for energies in the continuum, then we derive a general formula for calculating the meson-meson scattering amplitudes from these solutions. We thus obtain a completely nonperturbative procedure for the calculation of open-flavor meson-meson scattering cross sections from the diabatic potential, which is directly connected to lattice QCD calculations. A comprehensive analysis of various elastic cross sections for open-charm and open-bottom meson-meson pairs is performed in a wide range of the center-of-mass energies. The relevant structures are identified, showing a spectrum of quasi-conventional and unconventional quarkoniumlike states. In addition to the customary Breit-Wigner peaks we obtain nontrivial structures such as threshold cusps and minimums. Finally, our results are compared with existing data and with results from our previous bound-state--based analysis, finding full compatibility with both.
1504.00658
Ivan Girardi
I. Girardi, S. T. Petcov, A. V. Titov
Predictions for the Leptonic Dirac CP Violation Phase: a Systematic Phenomenological Analysis
37 pages, includes 8 figures and 6 tables; references added; typos corrected; matches published version
Eur. Phys. J. C75 (2015) 345
10.1140/epjc/s10052-015-3559-6
SISSA 14/2015/FISI, IPMU15-0032
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive predictions for the Dirac phase $\delta$ present in the $3\times 3$ unitary neutrino mixing matrix $U = U_e^{\dagger} \, U_{\nu}$, where $U_e$ and $U_{\nu}$ are $3\times 3$ unitary matrices which arise from the diagonalisation, respectively, of the charged lepton and the neutrino mass matrices. We consider forms of $U_e$ and $U_{\nu}$ allowing us to express $\delta$ as a function of three neutrino mixing angles, present in $U$, and the angles contained in $U_{\nu}$. We consider several forms of $U_{\nu}$ determined by, or associated with, symmetries, tri-bimaximal, bimaximal, etc., for which the angles in $U_{\nu}$ are fixed. For each of these forms and forms of $U_e$ allowing one to reproduce the measured values of the neutrino mixing angles, we construct the likelihood function for $\cos \delta$, using i) the latest results of the global fit analysis of neutrino oscillation data, and ii) the prospective sensitivities on the neutrino mixing angles. Our results, in particular, confirm the conclusion, reached in earlier similar studies, that the measurement of the Dirac phase in the neutrino mixing matrix, together with an improvement of the precision on the mixing angles, can provide unique information as regards the possible existence of symmetry in the lepton sector.
[ { "created": "Thu, 2 Apr 2015 19:37:00 GMT", "version": "v1" }, { "created": "Sun, 8 Nov 2015 20:15:58 GMT", "version": "v2" } ]
2015-11-10
[ [ "Girardi", "I.", "" ], [ "Petcov", "S. T.", "" ], [ "Titov", "A. V.", "" ] ]
We derive predictions for the Dirac phase $\delta$ present in the $3\times 3$ unitary neutrino mixing matrix $U = U_e^{\dagger} \, U_{\nu}$, where $U_e$ and $U_{\nu}$ are $3\times 3$ unitary matrices which arise from the diagonalisation, respectively, of the charged lepton and the neutrino mass matrices. We consider forms of $U_e$ and $U_{\nu}$ allowing us to express $\delta$ as a function of three neutrino mixing angles, present in $U$, and the angles contained in $U_{\nu}$. We consider several forms of $U_{\nu}$ determined by, or associated with, symmetries, tri-bimaximal, bimaximal, etc., for which the angles in $U_{\nu}$ are fixed. For each of these forms and forms of $U_e$ allowing one to reproduce the measured values of the neutrino mixing angles, we construct the likelihood function for $\cos \delta$, using i) the latest results of the global fit analysis of neutrino oscillation data, and ii) the prospective sensitivities on the neutrino mixing angles. Our results, in particular, confirm the conclusion, reached in earlier similar studies, that the measurement of the Dirac phase in the neutrino mixing matrix, together with an improvement of the precision on the mixing angles, can provide unique information as regards the possible existence of symmetry in the lepton sector.
1203.4165
Peihong Gu
Pei-Hong Gu
From dark matter to neutrinoless double beta decay
5 pages, 3 figures. Corrections and improvements
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Associated with two TeV-scale leptoquark scalars, a dark matter fermion which is the neutral component of an isotriplet can mediate a testable neutrinoless double beta decay at one-loop level. The dark matter fermion with determined mass and spin-independent scattering can be verified by the future dark matter direct detection experiments. We also discuss the implications on neutrino masses and baryon asymmetry.
[ { "created": "Mon, 19 Mar 2012 16:55:00 GMT", "version": "v1" }, { "created": "Tue, 27 Mar 2012 08:09:55 GMT", "version": "v2" }, { "created": "Thu, 13 Sep 2012 15:16:55 GMT", "version": "v3" } ]
2012-09-14
[ [ "Gu", "Pei-Hong", "" ] ]
Associated with two TeV-scale leptoquark scalars, a dark matter fermion which is the neutral component of an isotriplet can mediate a testable neutrinoless double beta decay at one-loop level. The dark matter fermion with determined mass and spin-independent scattering can be verified by the future dark matter direct detection experiments. We also discuss the implications on neutrino masses and baryon asymmetry.
hep-ph/0510111
Herbert Weigel
H. Weigel
Soliton Picture for Pentaquarks
6 pages, based on talk presented at the mini workshop, "Exciting Hadrons", Bled, July, 2005
null
null
null
hep-ph hep-ex nucl-ex nucl-th
null
In this talk I report on a thorough comparison between the bound state and rigid rotator approaches to generate baryon states with non--zero strangeness in chiral soliton models. This comparison shows that the scattering amplitude in the bound state approach contains contributions generated by the exchange of the rigid pentaquark excitation, and that the two approaches are consistent with each other in the large $N_C$ limit. The comparison paves the way to unambiguously compute the width of the $\Theta^+$ pentaquark in chiral soliton models.
[ { "created": "Mon, 10 Oct 2005 08:22:54 GMT", "version": "v1" } ]
2007-05-23
[ [ "Weigel", "H.", "" ] ]
In this talk I report on a thorough comparison between the bound state and rigid rotator approaches to generate baryon states with non--zero strangeness in chiral soliton models. This comparison shows that the scattering amplitude in the bound state approach contains contributions generated by the exchange of the rigid pentaquark excitation, and that the two approaches are consistent with each other in the large $N_C$ limit. The comparison paves the way to unambiguously compute the width of the $\Theta^+$ pentaquark in chiral soliton models.
0809.3124
Manuel Masip
Roberto Barcelo, Manuel Masip
A minimal Little Higgs model
16 pages. References added, fine tuning analysis included. Version to appear in PRD
Phys.Rev.D78:095012,2008
10.1103/PhysRevD.78.095012
UG-FT-236/08, CAFPE-106/08
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss a Little Higgs scenario that introduces below the TeV scale just the two minimal ingredients of these models, a vectorlike T quark and a singlet component (implying anomalous couplings) in the Higgs field, together with a pseudoscalar singlet \eta. In the model, which is a variation of Schmaltz's simplest Little Higgs model, all the extra vector bosons are much heavier than the T quark. In the Yukawa sector the global symmetry is approximate, implying a single large coupling per flavour, whereas in the scalar sector it is only broken at the loop level. We obtain the one-loop effective potential and show that it provides acceptable masses for the Higgs h and for the singlet \eta with no need for an extra \mu term. We find that m_\eta can be larger than m_h/2, which would forbid the (otherwise dominant) decay mode h -> \eta\eta.
[ { "created": "Thu, 18 Sep 2008 11:03:02 GMT", "version": "v1" }, { "created": "Mon, 22 Sep 2008 14:25:42 GMT", "version": "v2" }, { "created": "Thu, 6 Nov 2008 08:56:31 GMT", "version": "v3" } ]
2010-04-21
[ [ "Barcelo", "Roberto", "" ], [ "Masip", "Manuel", "" ] ]
We discuss a Little Higgs scenario that introduces below the TeV scale just the two minimal ingredients of these models, a vectorlike T quark and a singlet component (implying anomalous couplings) in the Higgs field, together with a pseudoscalar singlet \eta. In the model, which is a variation of Schmaltz's simplest Little Higgs model, all the extra vector bosons are much heavier than the T quark. In the Yukawa sector the global symmetry is approximate, implying a single large coupling per flavour, whereas in the scalar sector it is only broken at the loop level. We obtain the one-loop effective potential and show that it provides acceptable masses for the Higgs h and for the singlet \eta with no need for an extra \mu term. We find that m_\eta can be larger than m_h/2, which would forbid the (otherwise dominant) decay mode h -> \eta\eta.
hep-ph/9901349
Piotr Urban
M. Jezabek, P. Urban
Polarization in semileptonic B decays
13 pages, 1 figure, corrected typos, to appear in EPJ C
Eur.Phys.J.C11:317-323,1999
10.1007/s100520050636
null
hep-ph
null
The paper gives the polarization of the tau lepton in the semileptonic B decays with respect to the direction of the virtual W boson. The result is given including the nonperturbative HQET corrections.The perturbative QCD corrections are probably negligible as suggested by the existing results for the longitudinal polarization of the charged lepton (Jezabek and Urban, 1998).
[ { "created": "Tue, 19 Jan 1999 17:20:18 GMT", "version": "v1" }, { "created": "Fri, 19 Nov 1999 23:39:32 GMT", "version": "v2" } ]
2011-09-13
[ [ "Jezabek", "M.", "" ], [ "Urban", "P.", "" ] ]
The paper gives the polarization of the tau lepton in the semileptonic B decays with respect to the direction of the virtual W boson. The result is given including the nonperturbative HQET corrections.The perturbative QCD corrections are probably negligible as suggested by the existing results for the longitudinal polarization of the charged lepton (Jezabek and Urban, 1998).
hep-ph/0703279
Thomas Schwetz
Thomas Schwetz
Determination of the neutrino mass hierarchy in the regime of small matter effect
13 pages, 3 figures
JHEP 0705:093,2007
10.1088/1126-6708/2007/05/093
CERN-PH-TH/2007-060
hep-ph hep-ex
null
We point out a synergy between T-conjugated oscillation channels in the determination of the neutrino mass hierarchy with oscillation experiments with relatively short baselines (L < 700 km), where the matter effect is small. If information from all four oscillation channels $\nu_\mu\to\nu_e$, $\bar\nu_\mu\to\bar\nu_e$, $\nu_e\to\nu_\mu$ and $\bar\nu_e\to\bar\nu_\mu$ is available, a matter effect of few percent suffices to break the sign-degeneracy and allows to determine the neutrino mass hierarchy. The effect is discussed by analytical considerations of the relevant oscillation probabilities, and illustrated with numerical simulations of realistic experimental setups. Possible configurations where this method could be applied are the combination of a super beam experiment with a beta beam or a neutrino factory, or a (low energy) neutrino factory using a detector with muon and electron charge identification.
[ { "created": "Tue, 27 Mar 2007 10:10:57 GMT", "version": "v1" } ]
2010-10-27
[ [ "Schwetz", "Thomas", "" ] ]
We point out a synergy between T-conjugated oscillation channels in the determination of the neutrino mass hierarchy with oscillation experiments with relatively short baselines (L < 700 km), where the matter effect is small. If information from all four oscillation channels $\nu_\mu\to\nu_e$, $\bar\nu_\mu\to\bar\nu_e$, $\nu_e\to\nu_\mu$ and $\bar\nu_e\to\bar\nu_\mu$ is available, a matter effect of few percent suffices to break the sign-degeneracy and allows to determine the neutrino mass hierarchy. The effect is discussed by analytical considerations of the relevant oscillation probabilities, and illustrated with numerical simulations of realistic experimental setups. Possible configurations where this method could be applied are the combination of a super beam experiment with a beta beam or a neutrino factory, or a (low energy) neutrino factory using a detector with muon and electron charge identification.
1509.02194
Bastian Kubis
S. Holz, J. Plenter, C. W. Xiao, T. Dato, C. Hanhart, B. Kubis, U.-G. Mei{\ss}ner, A. Wirzba
Towards an improved understanding of $\eta \to \gamma^* \gamma^*$
15 pages, 10 figures; v2: major revision - author list extended, treatment of the left-hand cut corrected, discussion and references updated; v3: version published in EPJC
Eur. Phys. J. C 81 (2021) 1002
10.1140/epjc/s10052-021-09661-0
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We argue that high-quality data on the reaction $e^+e^-\to \pi^+\pi^-\eta$ will allow one to determine the doubly-virtual form factor $\eta\to \gamma^*\gamma^*$ in a model-independent way with controlled accuracy. This is an important step towards a reliable evaluation of the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. When analyzing the existing data for $e^+e^-\to\pi^+\pi^-\eta$ for total energies squared $k^2>1\text{GeV}^2$, we demonstrate that the effect of the $a_2$ meson provides a natural breaking mechanism for the commonly employed factorization ansatz in the doubly-virtual form factor $F_{\eta\gamma^*\gamma^*}(q^2,k^2)$. However, better data are needed to draw firm conclusions.
[ { "created": "Mon, 7 Sep 2015 21:14:41 GMT", "version": "v1" }, { "created": "Tue, 8 Jun 2021 13:39:19 GMT", "version": "v2" }, { "created": "Tue, 16 Nov 2021 08:41:20 GMT", "version": "v3" } ]
2021-11-17
[ [ "Holz", "S.", "" ], [ "Plenter", "J.", "" ], [ "Xiao", "C. W.", "" ], [ "Dato", "T.", "" ], [ "Hanhart", "C.", "" ], [ "Kubis", "B.", "" ], [ "Meißner", "U. -G.", "" ], [ "Wirzba", "A.", "" ] ]
We argue that high-quality data on the reaction $e^+e^-\to \pi^+\pi^-\eta$ will allow one to determine the doubly-virtual form factor $\eta\to \gamma^*\gamma^*$ in a model-independent way with controlled accuracy. This is an important step towards a reliable evaluation of the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. When analyzing the existing data for $e^+e^-\to\pi^+\pi^-\eta$ for total energies squared $k^2>1\text{GeV}^2$, we demonstrate that the effect of the $a_2$ meson provides a natural breaking mechanism for the commonly employed factorization ansatz in the doubly-virtual form factor $F_{\eta\gamma^*\gamma^*}(q^2,k^2)$. However, better data are needed to draw firm conclusions.
hep-ph/0510356
Per Osland
D. J. Miller, P. Osland, A. R. Raklev
Invariant mass distributions in cascade decays
39 pages, 14 figures (colour), JHEP class
JHEP 0603:034,2006
10.1088/1126-6708/2006/03/034
CERN-PH-TH/2005-121
hep-ph
null
We derive analytical expressions for the shape of the invariant mass distributions of massless Standard Model endproducts in cascade decays involving massive New Physics (NP) particles, D -> Cc -> Bbc -> Aabc, where the final NP particle A in the cascade is unobserved and where two of the particles a, b, c may be indistinguishable. Knowledge of these expressions can improve the determination of NP parameters at the LHC. The shape formulas are composite, but contain nothing more complicated than logarithms of simple expressions. We study the effects of cuts, final state radiation and detector effects on the distributions through Monte Carlo simulations, using a supersymmetric model as an example. We also consider how one can deal with the width of NP particles and with combinatorics from the misidentification of final state particles. The possible mismeasurements of NP masses through `feet' in the distributions are discussed. Finally, we demonstrate how the effects of different spin configurations can be included in the distributions.
[ { "created": "Thu, 27 Oct 2005 10:04:10 GMT", "version": "v1" } ]
2009-11-11
[ [ "Miller", "D. J.", "" ], [ "Osland", "P.", "" ], [ "Raklev", "A. R.", "" ] ]
We derive analytical expressions for the shape of the invariant mass distributions of massless Standard Model endproducts in cascade decays involving massive New Physics (NP) particles, D -> Cc -> Bbc -> Aabc, where the final NP particle A in the cascade is unobserved and where two of the particles a, b, c may be indistinguishable. Knowledge of these expressions can improve the determination of NP parameters at the LHC. The shape formulas are composite, but contain nothing more complicated than logarithms of simple expressions. We study the effects of cuts, final state radiation and detector effects on the distributions through Monte Carlo simulations, using a supersymmetric model as an example. We also consider how one can deal with the width of NP particles and with combinatorics from the misidentification of final state particles. The possible mismeasurements of NP masses through `feet' in the distributions are discussed. Finally, we demonstrate how the effects of different spin configurations can be included in the distributions.
2301.05714
Aditya Pathak
Aditya Pathak
The Catchment Area of Groomed Jets at NNLL
73 pages + appendices, 25 figures; Updated to journal version -- added additional section on comparison to previous results + improved restructuring of sections
J. High Energ. Phys. 2023, 54 (2023)
10.1007/JHEP08(2023)054
DESY-23-003
hep-ph
http://creativecommons.org/licenses/by/4.0/
Groomed jet observables have a dynamical catchment area which plays a key role in determining the leading nonperturbative power corrections and the impact of the underlying event. Based on field-theoretic arguments, certain moments of the groomed jet radius $R_g$ capture the entirety of the kinematic and grooming parameter dependence of these effects. These moments can be computed perturbatively in the soft drop operator expansion region where these corrections are small, but yet significant to be relevant for precision physics. A precise determination of these moments is thus crucial to faithfully isolate the universal contributions of hadronization and the underlying event. Building on a previously developed effective field theory framework for the doubly differential soft drop groomed jet mass and groomed jet radius measurement, we present here a calculation of these moments at next-to-next-to-leading-logarithmic (NNLL) accuracy including matching into the plain jet mass region. We compare our predictions for these moments against parton-shower Monte Carlo simulations and find good agreement. These results have applications for precision physics with soft drop jet mass such as determination of the strong coupling constant and the top quark mass and for improving hadronization models.
[ { "created": "Fri, 13 Jan 2023 19:00:01 GMT", "version": "v1" }, { "created": "Sat, 12 Aug 2023 09:57:04 GMT", "version": "v2" } ]
2023-08-15
[ [ "Pathak", "Aditya", "" ] ]
Groomed jet observables have a dynamical catchment area which plays a key role in determining the leading nonperturbative power corrections and the impact of the underlying event. Based on field-theoretic arguments, certain moments of the groomed jet radius $R_g$ capture the entirety of the kinematic and grooming parameter dependence of these effects. These moments can be computed perturbatively in the soft drop operator expansion region where these corrections are small, but yet significant to be relevant for precision physics. A precise determination of these moments is thus crucial to faithfully isolate the universal contributions of hadronization and the underlying event. Building on a previously developed effective field theory framework for the doubly differential soft drop groomed jet mass and groomed jet radius measurement, we present here a calculation of these moments at next-to-next-to-leading-logarithmic (NNLL) accuracy including matching into the plain jet mass region. We compare our predictions for these moments against parton-shower Monte Carlo simulations and find good agreement. These results have applications for precision physics with soft drop jet mass such as determination of the strong coupling constant and the top quark mass and for improving hadronization models.
hep-ph/9604420
Thomas G. Rizzo
Thomas G. Rizzo
Below Threshold $Z'$ Mass and Coupling Determinations at the NLC
10 pages, including 6 figures
null
null
SLAC-PUB-7151
hep-ph
null
We examine the capability of the NLC to determine the mass as well as the couplings to leptons and $b$-quarks of a new neutral gauge boson below production threshold. By using data collected at several different values of $\sqrt s$, we demonstrate how this can be done in a model-independent manner. [To appear in {\it Physics and Technology of the Next Linear Collider}, eds. D.\ Burke and M.\ Peskin]
[ { "created": "Mon, 29 Apr 1996 07:41:19 GMT", "version": "v1" } ]
2007-05-23
[ [ "Rizzo", "Thomas G.", "" ] ]
We examine the capability of the NLC to determine the mass as well as the couplings to leptons and $b$-quarks of a new neutral gauge boson below production threshold. By using data collected at several different values of $\sqrt s$, we demonstrate how this can be done in a model-independent manner. [To appear in {\it Physics and Technology of the Next Linear Collider}, eds. D.\ Burke and M.\ Peskin]
2305.02985
Giorgio Torrieri
Paulo Henrique De Moura, Kayman J. Goncalves, Giorgio Torrieri
Quarkonium spin alignment in a vortical medium
Version accepted for publication, Phys.Rev.D. arXiv admin note: text overlap with arXiv:2205.15087
null
null
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
We use a potential model to investigate the phenomenology of quarkonium in a thermal rotating medium, where vorticity and spin density are not necessarily in equilibrium. We find that the quarkonium spin density matrix, as well as the binding energy and melting temperature, are sensitive to both the vorticity and the lack of equilibrium between vorticity and spin. This means that quarkonium spin alignment is a sensitive probe for vorticity and spin within the hydrodynamic phase. Information unequivocably pointing to spin-orbit non-equilibrium dynamics can be obtained from a combined study of quarkonium relative abundance and spin alignment, as well as experimentally obtainable off-diagonal density matrix elements.
[ { "created": "Thu, 4 May 2023 16:50:16 GMT", "version": "v1" }, { "created": "Mon, 7 Aug 2023 14:40:59 GMT", "version": "v2" } ]
2023-08-08
[ [ "De Moura", "Paulo Henrique", "" ], [ "Goncalves", "Kayman J.", "" ], [ "Torrieri", "Giorgio", "" ] ]
We use a potential model to investigate the phenomenology of quarkonium in a thermal rotating medium, where vorticity and spin density are not necessarily in equilibrium. We find that the quarkonium spin density matrix, as well as the binding energy and melting temperature, are sensitive to both the vorticity and the lack of equilibrium between vorticity and spin. This means that quarkonium spin alignment is a sensitive probe for vorticity and spin within the hydrodynamic phase. Information unequivocably pointing to spin-orbit non-equilibrium dynamics can be obtained from a combined study of quarkonium relative abundance and spin alignment, as well as experimentally obtainable off-diagonal density matrix elements.
hep-ph/9303313
Edward Kolb
Edward W. Kolb and Igor I. Tkachev
Axion Miniclusters and Bose Stars
12 pages plus 3 eps figures (available via e-mail: rocky@fnas01.fnal.gov), LaTeX, FERMILAB--PUB--93/066-A
Phys.Rev.Lett. 71 (1993) 3051-3054
10.1103/PhysRevLett.71.3051
null
hep-ph astro-ph gr-qc
null
Evolution of inhomogeneities in the axion field around the QCD epoch is studied numerically, including for the first time important non-linear effects. It is found that perturbations on scales corresponding to causally disconnected regions at $T \sim 1 \, {\rm GeV}$ can lead to very dense axion clumps, with present density $\rho_a \ga 10^{-8}\,{\rm g \, cm^{-3}}$. This is high enough for the collisional $2a \rightarrow 2a$ process to lead to Bose--Einstein relaxation in the gravitationally bound clumps of axions, forming Bose stars.
[ { "created": "Mon, 29 Mar 1993 22:24:17 GMT", "version": "v1" } ]
2009-10-22
[ [ "Kolb", "Edward W.", "" ], [ "Tkachev", "Igor I.", "" ] ]
Evolution of inhomogeneities in the axion field around the QCD epoch is studied numerically, including for the first time important non-linear effects. It is found that perturbations on scales corresponding to causally disconnected regions at $T \sim 1 \, {\rm GeV}$ can lead to very dense axion clumps, with present density $\rho_a \ga 10^{-8}\,{\rm g \, cm^{-3}}$. This is high enough for the collisional $2a \rightarrow 2a$ process to lead to Bose--Einstein relaxation in the gravitationally bound clumps of axions, forming Bose stars.
hep-ph/0305049
Christopher T. Hill
William A. Bardeen, Estia J. Eichten, Christopher T. Hill
Chiral Multiplets of Heavy-Light Mesons
10 pages; minor editorial revisions; recomputed M1 transition
Phys.Rev.D68:054024,2003
10.1103/PhysRevD.68.054024
FERMILAB-Pub-03/071-T
hep-ph
null
The recent discovery of a narrow resonance in D_s+pi^0 by the BABAR collaboration is consistent with the interpretation of a heavy J^P(0+,1+) spin multiplet. This system is the parity partner of the groundstate (0-,1-) multiplet, which we argue is required in the implementation of SU(3)_L x SU(3)_R chiral symmetry in heavy-light meson systems. The (0+,1+)->(0-,1-)+pi transition couplings satisfy a Goldberger-Treiman relation, g_pi = Delta(M)/f_pi, where Delta(M) is the mass gap. The BABAR resonance fits the 0+ state, with a kinematically blocked principal decay mode to D+K. The allowed D_s+pi, D_s+2pi and electromagnetic transitions are computed from the full chiral theory and found to be suppressed, consistent with the narrowness of the state. This state establishes the chiral mass difference for all such heavy-quark chiral multiplets, and precise predictions exist for the analogous B_s and strange doubly-heavy baryon states.
[ { "created": "Mon, 5 May 2003 19:36:07 GMT", "version": "v1" }, { "created": "Fri, 9 May 2003 19:35:31 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bardeen", "William A.", "" ], [ "Eichten", "Estia J.", "" ], [ "Hill", "Christopher T.", "" ] ]
The recent discovery of a narrow resonance in D_s+pi^0 by the BABAR collaboration is consistent with the interpretation of a heavy J^P(0+,1+) spin multiplet. This system is the parity partner of the groundstate (0-,1-) multiplet, which we argue is required in the implementation of SU(3)_L x SU(3)_R chiral symmetry in heavy-light meson systems. The (0+,1+)->(0-,1-)+pi transition couplings satisfy a Goldberger-Treiman relation, g_pi = Delta(M)/f_pi, where Delta(M) is the mass gap. The BABAR resonance fits the 0+ state, with a kinematically blocked principal decay mode to D+K. The allowed D_s+pi, D_s+2pi and electromagnetic transitions are computed from the full chiral theory and found to be suppressed, consistent with the narrowness of the state. This state establishes the chiral mass difference for all such heavy-quark chiral multiplets, and precise predictions exist for the analogous B_s and strange doubly-heavy baryon states.
0811.2413
Michael Trusov
A.M.Badalian, Yu.A.Simonov, M.A.Trusov
Chiral shifts in heavy-light mesons
to be published in the Proceedings of the 14th International QCD Conference, 7th-12th July 2008, Montpellier, France
null
10.1016/j.nuclphysbps.2008.12.080
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The mass shifts of the $P$-wave $D_s$ and $B_s$ mesons due to coupling to $DK$ and $BK$ channels are calculated in the coupling channel model without fitting parameters. The strong mass shifts down for $0^+$ and ${1^+}'$ states have been obtained, while ${1^+}"$ and $2^+$ states remain almost in situ. The masses of $0^+$ and ${1^+}'$ states of $B_s$ mesons have been predicted.
[ { "created": "Fri, 14 Nov 2008 20:10:31 GMT", "version": "v1" } ]
2009-11-13
[ [ "Badalian", "A. M.", "" ], [ "Simonov", "Yu. A.", "" ], [ "Trusov", "M. A.", "" ] ]
The mass shifts of the $P$-wave $D_s$ and $B_s$ mesons due to coupling to $DK$ and $BK$ channels are calculated in the coupling channel model without fitting parameters. The strong mass shifts down for $0^+$ and ${1^+}'$ states have been obtained, while ${1^+}"$ and $2^+$ states remain almost in situ. The masses of $0^+$ and ${1^+}'$ states of $B_s$ mesons have been predicted.
1901.01539
Renata Jora
Renata Jora
Note on the Witten index and the dynamical breaking of a supersymmetric gauge theory
2 pages, title updated
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is known that in order for a supersymmetric gauge theory to be dynamically broken a necessary but not sufficient condition is that the Witten index $(-1)^F=n_b^0-n_f^0$ is zero. In the case the Witten index is zero it is in general hard to distinguish between theories with or without dynamical supersymmetry breaking. In this work we show that for a large class of theories the cancellation of the Witten index by itself signals the formation of a quark condensate and therefore produces dynamical supersymmetry breaking.
[ { "created": "Sun, 6 Jan 2019 13:30:10 GMT", "version": "v1" }, { "created": "Mon, 4 Mar 2019 11:09:02 GMT", "version": "v2" }, { "created": "Sun, 17 Mar 2019 05:11:21 GMT", "version": "v3" } ]
2019-03-19
[ [ "Jora", "Renata", "" ] ]
It is known that in order for a supersymmetric gauge theory to be dynamically broken a necessary but not sufficient condition is that the Witten index $(-1)^F=n_b^0-n_f^0$ is zero. In the case the Witten index is zero it is in general hard to distinguish between theories with or without dynamical supersymmetry breaking. In this work we show that for a large class of theories the cancellation of the Witten index by itself signals the formation of a quark condensate and therefore produces dynamical supersymmetry breaking.
1201.4374
Joseph Schechter
Joseph Schechter and M. Naeem Shahid
Neutrinos with velocities greater than c ?
5 pages, 1 figure, additional references added
null
10.1103/PhysRevD.85.093008
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A possible explanation of the results of the OPERA experiment is presented. Assuming that the usual value of c should be interpreted as the velocity of light in dark matter, we call the "true" velocity of light in vacuum, $c_t$. Then the OPERA neutrinos can be faster than c but slower than $c_t$. We also discuss the relationship between $c_t$ and neutrino masses.
[ { "created": "Fri, 20 Jan 2012 19:37:41 GMT", "version": "v1" }, { "created": "Mon, 27 Feb 2012 19:10:30 GMT", "version": "v2" } ]
2013-05-30
[ [ "Schechter", "Joseph", "" ], [ "Shahid", "M. Naeem", "" ] ]
A possible explanation of the results of the OPERA experiment is presented. Assuming that the usual value of c should be interpreted as the velocity of light in dark matter, we call the "true" velocity of light in vacuum, $c_t$. Then the OPERA neutrinos can be faster than c but slower than $c_t$. We also discuss the relationship between $c_t$ and neutrino masses.
0903.1796
Jonathan Rosner
Jonathan L. Rosner
Meson-Photon Transition Form Factors in the Charmonium Energy Range
7 pages, to be submitted to Phys. Rev. D. Version referring to new CLEO data
Phys.Rev.D79:097301,2009
10.1103/PhysRevD.79.097301
EFI 09-06
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of electron-positron collisions at center-of-mass energies corresponding to charmonium production has reached new levels of sensitivity thanks to experiments by the BES and CLEO Collaborations. Final states $\gamma P$, where $P$ is a pseudoscalar meson such as $\pi^0$, $\eta$, and $\eta'$ can arise either from charmonium decays or in the continuum through a virtual photon: $e^+ e^- \to \gamma^* \to \gamma P$. Estimates of this latter process are given at center-of-mass (c.m.) energies corresponding to the $J/\psi(1S)$, $\psi(2S)$, and $\psi(3770)$ resonances.
[ { "created": "Tue, 10 Mar 2009 15:23:49 GMT", "version": "v1" }, { "created": "Sat, 14 Mar 2009 22:32:10 GMT", "version": "v2" }, { "created": "Mon, 13 Apr 2009 19:55:27 GMT", "version": "v3" } ]
2009-07-30
[ [ "Rosner", "Jonathan L.", "" ] ]
The study of electron-positron collisions at center-of-mass energies corresponding to charmonium production has reached new levels of sensitivity thanks to experiments by the BES and CLEO Collaborations. Final states $\gamma P$, where $P$ is a pseudoscalar meson such as $\pi^0$, $\eta$, and $\eta'$ can arise either from charmonium decays or in the continuum through a virtual photon: $e^+ e^- \to \gamma^* \to \gamma P$. Estimates of this latter process are given at center-of-mass (c.m.) energies corresponding to the $J/\psi(1S)$, $\psi(2S)$, and $\psi(3770)$ resonances.
hep-ph/0205298
P. Q. Hung
S. Liuti (University of Virginia)
Unraveling Violations of Parton-Hadron Duality in ep Scattering
4 pages, Talk presented at the 37th Rencontres de Moriond, QCD and Hadronic Interactions, Les Arcs 1800 (France), March 16-23 2002
null
null
null
hep-ph
null
Recent studies of the Q^2 dependence of ep scattering in the large x region and in the Q^2 range: 1 < Q^2 <leq 30 Gev^2, confirm the validity of the phenomenon of quark-hadron duality - the similarity of the deep inelastic (parton) and resonance (hadron) spectra - for values of the invariant mass, W^2 > 2.4 GeV^2 At lower values of W^2, duality is found to be significantly violated by an amount that cannot be parametrized in terms of the first few terms of a series of power corrections. We present a dynamical model that explains the Q^2 dependence of the data: at low W^2, non-partonic components given by color neutral clusters dominate the cross section and the Q^2 dependence is governed by their mass spectrum, predicted within the preconfiment property of Q CD; at large W^2 the structure function is determined by a convolution of the cluster mass spectrum with the parton distributions.
[ { "created": "Mon, 27 May 2002 05:09:32 GMT", "version": "v1" } ]
2007-05-23
[ [ "Liuti", "S.", "", "University of Virginia" ] ]
Recent studies of the Q^2 dependence of ep scattering in the large x region and in the Q^2 range: 1 < Q^2 <leq 30 Gev^2, confirm the validity of the phenomenon of quark-hadron duality - the similarity of the deep inelastic (parton) and resonance (hadron) spectra - for values of the invariant mass, W^2 > 2.4 GeV^2 At lower values of W^2, duality is found to be significantly violated by an amount that cannot be parametrized in terms of the first few terms of a series of power corrections. We present a dynamical model that explains the Q^2 dependence of the data: at low W^2, non-partonic components given by color neutral clusters dominate the cross section and the Q^2 dependence is governed by their mass spectrum, predicted within the preconfiment property of Q CD; at large W^2 the structure function is determined by a convolution of the cluster mass spectrum with the parton distributions.
1507.08935
Florian Lyonnet
Florian Lyonnet, Aleksander Kusina, Karol Kova\v{r}\'ik, Tom\'a\v{s} Je\v{z}o, Fred Olness, Ingo Schienbein and Ji-Young Yu
On the intrinsic bottom content of the nucleon
Proceedings of the XXIII International Workshop on Deep Inelastic Scattering and Related Subjects, April 27 - May 1, 2015, Southern Methodist University, Dallas, Texas 75275. Change title, add a footnote
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We demonstrate that to a very good approximation the scale-evolution of the intrinsic heavy quark content of the nucleon is governed by non-singlet evolution equations. This allows us to analyze the intrinsic heavy quark distributions without having to resort to a full-fledged global analysis of parton distribution functions. This freedom is then exploited to model intrinsic bottom distributions which are so far missing in the literature in order to estimate the impact of this non-perturbative contribution to the bottom-quark PDF, and on parton--parton luminosities at the LHC. This technique can be applied to the case of intrinsic charm, albeit within the limitations outlined in the following.
[ { "created": "Fri, 31 Jul 2015 16:30:29 GMT", "version": "v1" }, { "created": "Mon, 17 Aug 2015 13:26:22 GMT", "version": "v2" } ]
2016-08-08
[ [ "Lyonnet", "Florian", "" ], [ "Kusina", "Aleksander", "" ], [ "Kovařík", "Karol", "" ], [ "Ježo", "Tomáš", "" ], [ "Olness", "Fred", "" ], [ "Schienbein", "Ingo", "" ], [ "Yu", "Ji-Young", "" ] ]
We demonstrate that to a very good approximation the scale-evolution of the intrinsic heavy quark content of the nucleon is governed by non-singlet evolution equations. This allows us to analyze the intrinsic heavy quark distributions without having to resort to a full-fledged global analysis of parton distribution functions. This freedom is then exploited to model intrinsic bottom distributions which are so far missing in the literature in order to estimate the impact of this non-perturbative contribution to the bottom-quark PDF, and on parton--parton luminosities at the LHC. This technique can be applied to the case of intrinsic charm, albeit within the limitations outlined in the following.
1311.0720
Abdelhak Djouadi
Abdelhak Djouadi
Implications of the Higgs discovery for the MSSM
21 pages, 27 figures. Review to appear in a special issue of EPJC and extended version of talks given at various recent conferences
null
10.1140/epjc/s10052-013-2704-3
Orsay preprint LPT-13-83
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The implications of the discovery of the Higgs boson at the LHC with a mass of approximately 125 GeV are summarised in the context of the minimal supersymmetric extension of the Standard Model, the MSSM. Discussed are the implications from the measured mass and production/decay rates of the observed particle and from the constraints in the search for the heavier Higgs states at the LHC.
[ { "created": "Mon, 4 Nov 2013 14:55:40 GMT", "version": "v1" } ]
2015-06-17
[ [ "Djouadi", "Abdelhak", "" ] ]
The implications of the discovery of the Higgs boson at the LHC with a mass of approximately 125 GeV are summarised in the context of the minimal supersymmetric extension of the Standard Model, the MSSM. Discussed are the implications from the measured mass and production/decay rates of the observed particle and from the constraints in the search for the heavier Higgs states at the LHC.
0810.4048
Konstantin Chetyrkin G.
P.A. Baikov, K.G. Chetyrkin and J.H. K\"uhn
Massless propagators: applications in QCD and QED
7 pages, contribution to the 8-th International Symposium on Radiative Corrections (RADCOR), October 1-5 2007, Florence, Italy
PoS RADCOR2007:023,2007
null
SFB/CPP-08-06, TTP08-03
hep-ph
http://creativecommons.org/licenses/by-nc-sa/3.0/
We report on two recent results based on the evaluation of five-loop massless propagators in QCD and QED: (i) corrections of order $\alpha_s^4$ to the absorptive part of the polarization function in QCD with $n_f=3$;(ii) the five-loop contribution to the $\beta$ function of quenched QED.
[ { "created": "Wed, 22 Oct 2008 16:41:20 GMT", "version": "v1" } ]
2009-01-08
[ [ "Baikov", "P. A.", "" ], [ "Chetyrkin", "K. G.", "" ], [ "Kühn", "J. H.", "" ] ]
We report on two recent results based on the evaluation of five-loop massless propagators in QCD and QED: (i) corrections of order $\alpha_s^4$ to the absorptive part of the polarization function in QCD with $n_f=3$;(ii) the five-loop contribution to the $\beta$ function of quenched QED.
0807.1054
Stefano Nicotri
P. Colangelo, F. De Fazio, F. Giannuzzi, F. Jugeau and S. Nicotri
Light scalar mesons in the soft-wall model of AdS/QCD
LaTeX, 17 pages, 1 figure
Phys.Rev.D78:055009,2008
10.1103/PhysRevD.78.055009
BARI-TH/08-593
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study light scalar mesons in the AdS/QCD soft-wall model with a background dilaton field. The masses and decay constants are compatible with experiment and QCD determinations if $a_0(980)$ and $f_0(980)$ are identified as the lightest scalar mesons; moreover, the states are organized in linear Regge trajectories with the same slope of vector mesons. Comparing the two-point correlation function of scalar operators in AdS and QCD, information about the condensates can be derived. Strong couplings of scalar states to pairs of light pseudoscalar mesons turn out to be small, at odds with experiment and QCD estimates: this discrepancy is related to the description of chiral symmetry breaking in this model.
[ { "created": "Mon, 7 Jul 2008 15:59:35 GMT", "version": "v1" } ]
2008-12-18
[ [ "Colangelo", "P.", "" ], [ "De Fazio", "F.", "" ], [ "Giannuzzi", "F.", "" ], [ "Jugeau", "F.", "" ], [ "Nicotri", "S.", "" ] ]
We study light scalar mesons in the AdS/QCD soft-wall model with a background dilaton field. The masses and decay constants are compatible with experiment and QCD determinations if $a_0(980)$ and $f_0(980)$ are identified as the lightest scalar mesons; moreover, the states are organized in linear Regge trajectories with the same slope of vector mesons. Comparing the two-point correlation function of scalar operators in AdS and QCD, information about the condensates can be derived. Strong couplings of scalar states to pairs of light pseudoscalar mesons turn out to be small, at odds with experiment and QCD estimates: this discrepancy is related to the description of chiral symmetry breaking in this model.
hep-ph/9810458
Zhu Shou-hua
Qing Hong Cao (PKU), Chong Sheng Li (PKU) and Shou Hua Zhu (ITP)
Leading Electroweak Corrections to the Neutral Higgs Boson Production at the Fermilab Tevatron
18 pages including 6 ps figures, submitted to Phys. Rev. D
Commun.Theor.Phys.33:275-284,2000
null
null
hep-ph
null
We calculate the leading electroweak corrections to the light neutral Higgs boson production via $q\bar q'\to WH$ at the Fermilab Tevatron in both the standard model and the minimal supersymmetric model, which arise from the top-quark and Higgs boson loop diagrams. We found that the leading electroweak corrections can exceed the QCD corrections for favorable values of the parameters in the MSSM, but such corrections are only about $-1% \sim -2%$ in the SM, which are much smaller than the QCD corrections. For the mass region of $90 < m_{h_0} < 120$ GeV, the leading electroweak corrections can reach -10% for large $\tan\beta$, and these corrections may be observable at a high luminosity Tevatron; at the least, new constraints on the $\tan\beta$ can be established.
[ { "created": "Fri, 23 Oct 1998 00:57:01 GMT", "version": "v1" } ]
2011-01-13
[ [ "Cao", "Qing Hong", "", "PKU" ], [ "Li", "Chong Sheng", "", "PKU" ], [ "Zhu", "Shou Hua", "", "ITP" ] ]
We calculate the leading electroweak corrections to the light neutral Higgs boson production via $q\bar q'\to WH$ at the Fermilab Tevatron in both the standard model and the minimal supersymmetric model, which arise from the top-quark and Higgs boson loop diagrams. We found that the leading electroweak corrections can exceed the QCD corrections for favorable values of the parameters in the MSSM, but such corrections are only about $-1% \sim -2%$ in the SM, which are much smaller than the QCD corrections. For the mass region of $90 < m_{h_0} < 120$ GeV, the leading electroweak corrections can reach -10% for large $\tan\beta$, and these corrections may be observable at a high luminosity Tevatron; at the least, new constraints on the $\tan\beta$ can be established.
2203.10440
Kentarou Mawatari
Junmou Chen, Kaoru Hagiwara, Junichi Kanzaki, and Kentarou Mawatari
Helicity amplitudes without gauge cancellation for electroweak processes
26 pages, 14 figures, 9 tables; v2: references added; v3: some issues clarified, references added, version to appear in EPJC
null
null
KEK-TH-2403, IPMU22-0008
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the 5-component representation of weak bosons, the first four components make a Lorentz four vector, representing the transverse and longitudinal polarizations excluding the scalar component of the weak bosons, whereas its fifth component corresponds to the Goldstone boson. We obtain the $5\times 5$ component propagators of off-shell weak bosons, proposed previously and named after the Goldstone boson equivalence theorem, by starting from the unitary-gauge representation of the tree-level scattering amplitudes, and by applying the BRST (Becchi--Rouet--Stora--Tyutin) identities to the two sub-amplitudes connected by each off-shell weak-boson line. By replacing all weak boson vertices with those among the off-shell 5-component wavefunctions, we arrive at the expression of the electroweak scattering amplitudes, where the magnitude of each Feynman amplitude has the correct on-shell limits for all internal propagators, and hence with no artificial gauge cancellation among diagrams. Although our derivation is limited to the tree-level only, it allows us to study the properties of each Feynman amplitude separately, and then learn how they interfere in the full amplitudes. We implement the 5-component weak boson propagators and their vertices in the numerical helicity amplitude calculation code HELAS (Helicity Amplitude Subroutines), so that an automatic amplitude generation program such as MadGraph can generate the scattering amplitudes without gauge cancellation. We present results for several high-energy scattering processes where subtle gauge-theory cancellation among diagrams takes place in all the other known approaches.
[ { "created": "Sun, 20 Mar 2022 03:32:45 GMT", "version": "v1" }, { "created": "Tue, 29 Mar 2022 15:42:21 GMT", "version": "v2" }, { "created": "Wed, 11 Oct 2023 07:39:44 GMT", "version": "v3" } ]
2023-10-12
[ [ "Chen", "Junmou", "" ], [ "Hagiwara", "Kaoru", "" ], [ "Kanzaki", "Junichi", "" ], [ "Mawatari", "Kentarou", "" ] ]
In the 5-component representation of weak bosons, the first four components make a Lorentz four vector, representing the transverse and longitudinal polarizations excluding the scalar component of the weak bosons, whereas its fifth component corresponds to the Goldstone boson. We obtain the $5\times 5$ component propagators of off-shell weak bosons, proposed previously and named after the Goldstone boson equivalence theorem, by starting from the unitary-gauge representation of the tree-level scattering amplitudes, and by applying the BRST (Becchi--Rouet--Stora--Tyutin) identities to the two sub-amplitudes connected by each off-shell weak-boson line. By replacing all weak boson vertices with those among the off-shell 5-component wavefunctions, we arrive at the expression of the electroweak scattering amplitudes, where the magnitude of each Feynman amplitude has the correct on-shell limits for all internal propagators, and hence with no artificial gauge cancellation among diagrams. Although our derivation is limited to the tree-level only, it allows us to study the properties of each Feynman amplitude separately, and then learn how they interfere in the full amplitudes. We implement the 5-component weak boson propagators and their vertices in the numerical helicity amplitude calculation code HELAS (Helicity Amplitude Subroutines), so that an automatic amplitude generation program such as MadGraph can generate the scattering amplitudes without gauge cancellation. We present results for several high-energy scattering processes where subtle gauge-theory cancellation among diagrams takes place in all the other known approaches.
1009.3077
Tatsumi Aoyama
T. Aoyama, M. Hayakawa, T. Kinoshita, M. Nio
Tenth-order lepton g-2: Contribution of some fourth-order radiative corrections to the sixth-order g-2 containing light-by-light-scattering subdiagrams
17 pages, 5 figures
Phys.Rev.D82:113004,2010
10.1103/PhysRevD.82.113004
RIKEN-TH-192
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper reports the tenth-order QED contribution to lepton g-2 from diagrams of three gauge-invariant sets VI(d), VI(g), and VI(h), which are obtained by including various fourth-order radiative corrections to the sixth-order g-2 containing light-by-light-scattering subdiagrams. In the case of electron g-2, they consist of 492, 480, and 630 vertex Feynman diagrams, respectively. The results of numerical integration, including mass-dependent terms containing muon loops, are 1.8418(95) (alpha/pi)^5 for the Set VI(d), -1.5918(65) (alpha/pi)^5 for the Set VI(g), and 0.1797(40) (alpha/pi)^5 for the Set VI(h), respectively. We also report the contributions to the muon g-2, which derive from diagrams containing an electron, muon or tau lepton loop: Their sums are -5.876(802) (alpha/pi)^5 for the Set VI(d), 5.710(490) (alpha/pi)^5 for the Set VI(g), and -8.361(232) (alpha/pi)^5 for the Set VI(h), respectively.
[ { "created": "Thu, 16 Sep 2010 02:24:26 GMT", "version": "v1" } ]
2010-12-24
[ [ "Aoyama", "T.", "" ], [ "Hayakawa", "M.", "" ], [ "Kinoshita", "T.", "" ], [ "Nio", "M.", "" ] ]
This paper reports the tenth-order QED contribution to lepton g-2 from diagrams of three gauge-invariant sets VI(d), VI(g), and VI(h), which are obtained by including various fourth-order radiative corrections to the sixth-order g-2 containing light-by-light-scattering subdiagrams. In the case of electron g-2, they consist of 492, 480, and 630 vertex Feynman diagrams, respectively. The results of numerical integration, including mass-dependent terms containing muon loops, are 1.8418(95) (alpha/pi)^5 for the Set VI(d), -1.5918(65) (alpha/pi)^5 for the Set VI(g), and 0.1797(40) (alpha/pi)^5 for the Set VI(h), respectively. We also report the contributions to the muon g-2, which derive from diagrams containing an electron, muon or tau lepton loop: Their sums are -5.876(802) (alpha/pi)^5 for the Set VI(d), 5.710(490) (alpha/pi)^5 for the Set VI(g), and -8.361(232) (alpha/pi)^5 for the Set VI(h), respectively.
2212.12153
Sambit Kumar Pusty
Sambit Kumar Pusty, Dhiren Panda, and Aishwarya Bhatta
Investigating $ \Upsilon(ns) \to \tau^+ \tau^- $ decay in the Leptoquark scenario
14 pages, 3 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Several measurements on $R_D, R_{D^*}$, and $R_{J/ \psi}$ by the BaBar, Belle, and LHCb experiments show significant deviations from their Standard Model (SM) predictions, which illustrate the fact that the concept of lepton flavor universality (LFU) is violated in semileptonic $B$ meson as well as leptonic $\Upsilon(ns)(n=1,2,3)$ decays. Recently BaBar experiment announced that at $1.8\sigma$ level, $R_\Upsilon(3s)= {\rm Br}(\Upsilon(3s) \to \tau \bar{\tau})/{\rm Br}(\Upsilon(3s) \to \mu \bar{\mu})$ shows an acceptance with the SM. These fascinating findings point towards the possible implication of new physics in the $b \to c \tau \bar{\nu}$ transitions, which in turn, creates a new direction to look for new physics in $b \bar{b} \to \tau \bar{\tau} $ process. Thereby, the new physics contributions to the $b \to c \tau \bar{\nu}$ process would inevitably alter the $b \bar{b} \to \tau \bar{\tau} $ transitions. Here we conduct a $\chi^{2}$ fit to constraining the new parameters by using the measured values of $ R_D$, $R{_D*}$, $ R_{J/ \psi}$, $ R_{X_C}$, $F_L (D^*)$ and $P_{\tau} (D^*)$. In this context, we investigate the effect of constrained new physics couplings on the branching ratios and LFU parameters $R_{\Upsilon(ns)}$ through leptoquark models such as $S_3, \tilde{S_1}, \tilde{R_2}, U_1, U_3 $ and $ V_2$.
[ { "created": "Fri, 23 Dec 2022 05:15:04 GMT", "version": "v1" }, { "created": "Fri, 27 Jan 2023 13:27:25 GMT", "version": "v2" } ]
2023-01-30
[ [ "Pusty", "Sambit Kumar", "" ], [ "Panda", "Dhiren", "" ], [ "Bhatta", "Aishwarya", "" ] ]
Several measurements on $R_D, R_{D^*}$, and $R_{J/ \psi}$ by the BaBar, Belle, and LHCb experiments show significant deviations from their Standard Model (SM) predictions, which illustrate the fact that the concept of lepton flavor universality (LFU) is violated in semileptonic $B$ meson as well as leptonic $\Upsilon(ns)(n=1,2,3)$ decays. Recently BaBar experiment announced that at $1.8\sigma$ level, $R_\Upsilon(3s)= {\rm Br}(\Upsilon(3s) \to \tau \bar{\tau})/{\rm Br}(\Upsilon(3s) \to \mu \bar{\mu})$ shows an acceptance with the SM. These fascinating findings point towards the possible implication of new physics in the $b \to c \tau \bar{\nu}$ transitions, which in turn, creates a new direction to look for new physics in $b \bar{b} \to \tau \bar{\tau} $ process. Thereby, the new physics contributions to the $b \to c \tau \bar{\nu}$ process would inevitably alter the $b \bar{b} \to \tau \bar{\tau} $ transitions. Here we conduct a $\chi^{2}$ fit to constraining the new parameters by using the measured values of $ R_D$, $R{_D*}$, $ R_{J/ \psi}$, $ R_{X_C}$, $F_L (D^*)$ and $P_{\tau} (D^*)$. In this context, we investigate the effect of constrained new physics couplings on the branching ratios and LFU parameters $R_{\Upsilon(ns)}$ through leptoquark models such as $S_3, \tilde{S_1}, \tilde{R_2}, U_1, U_3 $ and $ V_2$.
hep-ph/9310241
null
P.Zenczykowski
Weak Hyperon Decays: Quark Sea and SU(3) Symmetry Breaking
26 pages, LATEX, 1647/PH IFJ Krakow
Phys.Rev. D50 (1994) 3285-3294
10.1103/PhysRevD.50.3285
null
hep-ph
null
An explanation of the difference in the values of the apparent $f/d$ ratios for the S- and P- wave amplitudes of nonleptonic hyperon decays is proposed. The argument is formulated in the framework of the standard pole model with $(56,0^{+})$ ground-state and $(70,1^{-})$ excited baryons as intermediate states for the P- and S- waves respectively. Under the assumption that the dominant part of the deviation of $(f/d)_{P-wave}$ from $-1$ is due to large quark sea effects, $SU(3)$ symmetry breaking in energy denominators is shown to lead to a prediction for $(f/d)_{S-wave}$ which is in excellent agreement with experiment. This corroborates our previous unitarity calculations which indicated that the matrix elements $<B|H^{p.c.}_{weak}|B'>$ of the parity conserving weak Hamiltonian between the ground-state baryons are characterized by $f_{0}/d_{0} \approx -1.6$ or more. A brief discussion of the problem of the relative size of S- and P- wave amplitudes is given. Finally, implications for weak radiative hyperon decays are also discussed.
[ { "created": "Thu, 7 Oct 1993 15:14:00 GMT", "version": "v1" } ]
2009-10-22
[ [ "Zenczykowski", "P.", "" ] ]
An explanation of the difference in the values of the apparent $f/d$ ratios for the S- and P- wave amplitudes of nonleptonic hyperon decays is proposed. The argument is formulated in the framework of the standard pole model with $(56,0^{+})$ ground-state and $(70,1^{-})$ excited baryons as intermediate states for the P- and S- waves respectively. Under the assumption that the dominant part of the deviation of $(f/d)_{P-wave}$ from $-1$ is due to large quark sea effects, $SU(3)$ symmetry breaking in energy denominators is shown to lead to a prediction for $(f/d)_{S-wave}$ which is in excellent agreement with experiment. This corroborates our previous unitarity calculations which indicated that the matrix elements $<B|H^{p.c.}_{weak}|B'>$ of the parity conserving weak Hamiltonian between the ground-state baryons are characterized by $f_{0}/d_{0} \approx -1.6$ or more. A brief discussion of the problem of the relative size of S- and P- wave amplitudes is given. Finally, implications for weak radiative hyperon decays are also discussed.
0804.2975
Pierre Artoisenet
P. Artoisenet
J/psi production in association with a charm-quark pair at the Tevatron
9 pages, 6 figures, proceedings of the Ninth Workshop on Non-Perturbative Quantum Chromodynamics
ECONF C0706044:21,2007
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I study the direct hadroproduction of J\psi associated with a charm-quark pair at leading order in alpha_S and v in NRQCD. This process provides an interesting signature that could be studied at the Tevatron. I consider both colour-singlet and colour-octet transitions. I compare our results to the fragmentation approximation and discuss the associated experimental signatures.
[ { "created": "Fri, 18 Apr 2008 08:52:27 GMT", "version": "v1" } ]
2011-03-23
[ [ "Artoisenet", "P.", "" ] ]
I study the direct hadroproduction of J\psi associated with a charm-quark pair at leading order in alpha_S and v in NRQCD. This process provides an interesting signature that could be studied at the Tevatron. I consider both colour-singlet and colour-octet transitions. I compare our results to the fragmentation approximation and discuss the associated experimental signatures.
1402.2909
David London
Bhubanjyoti Bhattacharya, Michael Gronau, Maxime Imbeault, David London and Jonathan L. Rosner
Charmless B -> PPP Decays: the Fully-Symmetric Final State
24 pages, 1 figure. Several more detailed explanations added. Analysis and conclusions unchanged
Phys. Rev. D 89, 074043 (2014)
10.1103/PhysRevD.89.074043
UdeM-GPP-TH-14-230, TECHNION-PH-14-3, EFI 14-3
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In charmless B -> PPP decays, where P is a pseudoscalar meson, there are six possibilities for the symmetry of the final state. In this paper, for P=pi,K, we examine the properties of the fully-symmetric final state. We present expressions for all 32 B -> PPP decay amplitudes as a function of both SU(3) reduced matrix elements and diagrams, demonstrating the equivalence of diagrams and SU(3). We also give 25 relations among the amplitudes in the SU(3) limit, as well as those that appear when the diagrams E/A/PA are neglected. In the SU(3) limit, one has the equalities \sqrt{2} A(B+ -> K+ pi+ pi-)_{FS} = A(B+ -> K+ K+ K-)_{FS} and \sqrt{2} A(B+ -> pi+ K+ K-)_{FS} = A(B+ -> pi+ pi+ pi-)_{FS}, where FS denotes the fully-symmetric final state. These provide good tests of the standard model that can be carried out now by the LHCb Collaboration.
[ { "created": "Wed, 12 Feb 2014 17:41:33 GMT", "version": "v1" }, { "created": "Tue, 25 Mar 2014 15:57:25 GMT", "version": "v2" } ]
2014-07-22
[ [ "Bhattacharya", "Bhubanjyoti", "" ], [ "Gronau", "Michael", "" ], [ "Imbeault", "Maxime", "" ], [ "London", "David", "" ], [ "Rosner", "Jonathan L.", "" ] ]
In charmless B -> PPP decays, where P is a pseudoscalar meson, there are six possibilities for the symmetry of the final state. In this paper, for P=pi,K, we examine the properties of the fully-symmetric final state. We present expressions for all 32 B -> PPP decay amplitudes as a function of both SU(3) reduced matrix elements and diagrams, demonstrating the equivalence of diagrams and SU(3). We also give 25 relations among the amplitudes in the SU(3) limit, as well as those that appear when the diagrams E/A/PA are neglected. In the SU(3) limit, one has the equalities \sqrt{2} A(B+ -> K+ pi+ pi-)_{FS} = A(B+ -> K+ K+ K-)_{FS} and \sqrt{2} A(B+ -> pi+ K+ K-)_{FS} = A(B+ -> pi+ pi+ pi-)_{FS}, where FS denotes the fully-symmetric final state. These provide good tests of the standard model that can be carried out now by the LHCb Collaboration.
1612.00511
Marc Thomas Dr
Alexander Belyaev, Giacomo Cacciapaglia, Igor P. Ivanov, Felipe Rojas, Marc Thomas
Anatomy of the Inert Two Higgs Doublet Model in the light of the LHC and non-LHC Dark Matter Searches
Text and figures are updated to be consistent with with published PRD version
Phys. Rev. D 97, 035011 (2018)
10.1103/PhysRevD.97.035011
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The inert Two Higgs Doublet Model (i2HDM) is a theoretically well-motivated example of a minimal consistent Dark Matter(DM) model which provides mono-jet, mono-Z, mono-Higgs and Vector-Boson-Fusion+Missing Transverse Momentum signatures at the LHC, complemented by signals in direct and indirect DM search experiments. In this paper we have performed a detailed analysis of the constraints in the full 5D parameter space of the i2HDM, coming from perturbativity, unitarity, electroweak precision data, Higgs data from LHC, DM relic density, direct/indirect DM detection and LHC mono-jet analysis, as well as implications of experimental LHC studies on disappearing charged tracks relevant to high DM mass region. We demonstrate the complementarity of the above constraints and present projections for future LHC data and direct DM detection experiments to probe further i2HDM parameter space. The model is implemented into the CalcHEP and micrOMEGAs packages, which are publicly available at the HEPMDB database, and is ready for a further exploration in the context of the LHC, relic density and DM direct detection.
[ { "created": "Thu, 1 Dec 2016 23:14:01 GMT", "version": "v1" }, { "created": "Sun, 26 Jul 2020 09:57:44 GMT", "version": "v2" } ]
2020-07-28
[ [ "Belyaev", "Alexander", "" ], [ "Cacciapaglia", "Giacomo", "" ], [ "Ivanov", "Igor P.", "" ], [ "Rojas", "Felipe", "" ], [ "Thomas", "Marc", "" ] ]
The inert Two Higgs Doublet Model (i2HDM) is a theoretically well-motivated example of a minimal consistent Dark Matter(DM) model which provides mono-jet, mono-Z, mono-Higgs and Vector-Boson-Fusion+Missing Transverse Momentum signatures at the LHC, complemented by signals in direct and indirect DM search experiments. In this paper we have performed a detailed analysis of the constraints in the full 5D parameter space of the i2HDM, coming from perturbativity, unitarity, electroweak precision data, Higgs data from LHC, DM relic density, direct/indirect DM detection and LHC mono-jet analysis, as well as implications of experimental LHC studies on disappearing charged tracks relevant to high DM mass region. We demonstrate the complementarity of the above constraints and present projections for future LHC data and direct DM detection experiments to probe further i2HDM parameter space. The model is implemented into the CalcHEP and micrOMEGAs packages, which are publicly available at the HEPMDB database, and is ready for a further exploration in the context of the LHC, relic density and DM direct detection.
hep-ph/0701096
Jose Antonio Oller
Jose Antonio Oller, Joaquim Prades and Michela Verbeni
Meson-Baryon Effective Chiral Lagrangians at O(q^3) Revisited
7 pages, 1 table. A mistake was corrected. Our Lagrangian and that of [2] contain the same number of monomials
null
null
CERN-PH-TH/2007-004
hep-ph nucl-th
null
After our work was published, Frink and Mei{\ss}ner \cite{FM06} pointed out that our {\cal O}(q^3) three-flavour meson-baryon chiral Lagrangian was not minimal. Here, we discuss their findings and revise ours accordingly. We find that eight monomials in our ${\cal O}(q^3)$ Lagrangian are not independent, but in addition, two monomials were wrongly discarded, which, as a result, makes the agreement in the number of independent monomials with \cite{FM06} complete.
[ { "created": "Fri, 12 Jan 2007 11:55:49 GMT", "version": "v1" }, { "created": "Tue, 6 Mar 2007 10:31:48 GMT", "version": "v2" } ]
2007-05-23
[ [ "Oller", "Jose Antonio", "" ], [ "Prades", "Joaquim", "" ], [ "Verbeni", "Michela", "" ] ]
After our work was published, Frink and Mei{\ss}ner \cite{FM06} pointed out that our {\cal O}(q^3) three-flavour meson-baryon chiral Lagrangian was not minimal. Here, we discuss their findings and revise ours accordingly. We find that eight monomials in our ${\cal O}(q^3)$ Lagrangian are not independent, but in addition, two monomials were wrongly discarded, which, as a result, makes the agreement in the number of independent monomials with \cite{FM06} complete.
0902.0470
Nita Sinha
Nita Sinha
Status of CP Violation
6 pages, 3 figures, presented at the 18th International Conference on Particles And Nuclei (PANIC08), 9-14 November 2008, Eilat, Israel
Nucl.Phys.A827:469c-474c,2009
10.1016/j.nuclphysa.2009.05.102
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Standard Model parametrization of CP violation is described. Tests of this parametrization using the observed heavy flavour decays and implications for New physics are discussed.
[ { "created": "Tue, 3 Feb 2009 18:03:46 GMT", "version": "v1" } ]
2010-02-25
[ [ "Sinha", "Nita", "" ] ]
The Standard Model parametrization of CP violation is described. Tests of this parametrization using the observed heavy flavour decays and implications for New physics are discussed.
hep-ph/0210447
Jonathan Thomas Lenaghan
J. Wirstam, J. T. Lenaghan, K. Splittorff
Melting the Diquark Condensate in Two-Color QCD: A Renormalization Group Analysis
10 pages, 1 figure, revtex, reference added, version to appear in PRD
Phys.Rev. D67 (2003) 034021
10.1103/PhysRevD.67.034021
BNL-71005-2003-JA, SUNY-NTG-02/33
hep-ph hep-lat hep-th
null
We use a Landau theory and the epsilon expansion to study the superfluid phase transition of two-color QCD at nonzero temperature, T, and baryonic chemical potential, mu. At low T, and for N_f flavors of massless quarks, the global SU(N_f) \times SU(N_f) \times U(1) symmetry is spontaneously broken by a diquark condensate down to Sp(N_f) \times Sp(N_f) for any mu > 0. As the temperature increases, the diquark condensate melts, and at sufficiently large T the symmetry is restored. Using renormalization group arguments, we find that in the presence of the chiral anomaly term there can be a second order phase transition when N_f=2 or N_f >= 6, while the transition is first order for N_f=4. We discuss the relevance of these results for the emergence of a tricritical point recently observed in lattice simulations.
[ { "created": "Thu, 31 Oct 2002 18:27:04 GMT", "version": "v1" }, { "created": "Wed, 22 Jan 2003 18:20:29 GMT", "version": "v2" } ]
2009-11-07
[ [ "Wirstam", "J.", "" ], [ "Lenaghan", "J. T.", "" ], [ "Splittorff", "K.", "" ] ]
We use a Landau theory and the epsilon expansion to study the superfluid phase transition of two-color QCD at nonzero temperature, T, and baryonic chemical potential, mu. At low T, and for N_f flavors of massless quarks, the global SU(N_f) \times SU(N_f) \times U(1) symmetry is spontaneously broken by a diquark condensate down to Sp(N_f) \times Sp(N_f) for any mu > 0. As the temperature increases, the diquark condensate melts, and at sufficiently large T the symmetry is restored. Using renormalization group arguments, we find that in the presence of the chiral anomaly term there can be a second order phase transition when N_f=2 or N_f >= 6, while the transition is first order for N_f=4. We discuss the relevance of these results for the emergence of a tricritical point recently observed in lattice simulations.