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1409.6508
Kiyoharu Kawana
Yuta Hamada, Hikaru Kawai, Kiyoharu Kawana
Weak Scale From the Maximum Entropy Principle
21 pages, 10 figures; references added, version to appear in PTEP (v2)
Prog. Theor. Exp. Phys. 2015, 033B06
10.1093/ptep/ptv011
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\cal{O}}(300\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \begin{equation} v_{h}\sim\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\nonumber\end{equation} where $y_{e}$ is the Yukawa coupling of electron, $T_{BBN}$ is the temperature where the Big Bang Nucleosynthesis starts and $M_{pl}$ is the Planck mass.
[ { "created": "Tue, 23 Sep 2014 12:28:16 GMT", "version": "v1" }, { "created": "Sat, 28 Mar 2015 10:17:01 GMT", "version": "v2" } ]
2015-03-31
[ [ "Hamada", "Yuta", "" ], [ "Kawai", "Hikaru", "" ], [ "Kawana", "Kiyoharu", "" ] ]
The theory of multiverse and wormholes suggests that the parameters of the Standard Model are fixed in such a way that the radiation of the $S^{3}$ universe at the final stage $S_{rad}$ becomes maximum, which we call the maximum entropy principle. Although it is difficult to confirm this principle generally, for a few parameters of the Standard Model, we can check whether $S_{rad}$ actually becomes maximum at the observed values. In this paper, we regard $S_{rad}$ at the final stage as a function of the weak scale ( the Higgs expectation value ) $v_{h}$, and show that it becomes maximum around $v_{h}={\cal{O}}(300\text{GeV})$ when the dimensionless couplings in the Standard Model, that is, the Higgs self coupling, the gauge couplings, and the Yukawa couplings are fixed. Roughly speaking, we find that the weak scale is given by \begin{equation} v_{h}\sim\frac{T_{BBN}^{2}}{M_{pl}y_{e}^{5}},\nonumber\end{equation} where $y_{e}$ is the Yukawa coupling of electron, $T_{BBN}$ is the temperature where the Big Bang Nucleosynthesis starts and $M_{pl}$ is the Planck mass.
2202.08013
Akira Watanabe
Zhibo Liu, Wei Xie, Fei Sun, Shuang Li, Akira Watanabe
Elastic pion-proton and pion-pion scattering at high energies in holographic QCD
9 pages, 5 figures, version accepted for publication in Phys. Rev. D
null
10.1103/PhysRevD.106.054025
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The total and differential cross sections of high energy pion-proton and pion-pion scattering are investigated in a holographic QCD model, focusing on the Regge regime in which the Pomeron exchange gives the dominant contribution to those cross sections. The Pomeron is described by the Reggeized spin-2 particle propagator, and the hadron-Pomeron couplings are given by gravitational form factors of the hadrons, which are obtained from the bottom-up AdS/QCD models. Since the parameters, which characterize the Pomeron trajectory, have been determined in a preceding study of the proton-proton scattering, the pion-proton cross sections can be expressed with a single adjustable parameter. Once this parameter is determined by the experimental data of the pion-proton total cross section, its differential cross section and the pion-pion cross sections can be calculated without any additional parameter. Although the currently available data are limited, it is found that our calculation is consistent with those. Our predictions are explicitly shown, and the present model can be tested at the future experimental facilities.
[ { "created": "Wed, 16 Feb 2022 12:03:32 GMT", "version": "v1" }, { "created": "Sat, 10 Sep 2022 05:26:46 GMT", "version": "v2" } ]
2022-10-05
[ [ "Liu", "Zhibo", "" ], [ "Xie", "Wei", "" ], [ "Sun", "Fei", "" ], [ "Li", "Shuang", "" ], [ "Watanabe", "Akira", "" ] ]
The total and differential cross sections of high energy pion-proton and pion-pion scattering are investigated in a holographic QCD model, focusing on the Regge regime in which the Pomeron exchange gives the dominant contribution to those cross sections. The Pomeron is described by the Reggeized spin-2 particle propagator, and the hadron-Pomeron couplings are given by gravitational form factors of the hadrons, which are obtained from the bottom-up AdS/QCD models. Since the parameters, which characterize the Pomeron trajectory, have been determined in a preceding study of the proton-proton scattering, the pion-proton cross sections can be expressed with a single adjustable parameter. Once this parameter is determined by the experimental data of the pion-proton total cross section, its differential cross section and the pion-pion cross sections can be calculated without any additional parameter. Although the currently available data are limited, it is found that our calculation is consistent with those. Our predictions are explicitly shown, and the present model can be tested at the future experimental facilities.
1305.1817
Giorgio Busoni
Giorgio Busoni, Andrea De Simone, Wei-Chih Huang
On the Minimum Dark Matter Mass Testable by Neutrinos from the Sun
15 pages, 6 figures, v2: Figure 6 corrected
JCAP 1307:010,2013
10.1088/1475-7516/2013/07/010
CERN-PH-TH/2013-091, SISSA 19/2013/FISI
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss a limitation on extracting bounds on the scattering cross section of dark matter with nucleons, using neutrinos from the Sun. If the dark matter particle is sufficiently light (less than about 4 GeV), the effect of evaporation is not negligible and the capture process goes in equilibrium with the evaporation. In this regime, the flux of solar neutrinos of dark matter origin becomes independent of the scattering cross section and therefore no constraint can be placed on it. We find the minimum values of dark matter masses for which the scattering cross section on nucleons can be probed using neutrinos from the Sun. We also provide simple and accurate fitting functions for all the relevant processes of GeV-scale dark matter in the Sun.
[ { "created": "Wed, 8 May 2013 13:42:41 GMT", "version": "v1" }, { "created": "Fri, 10 May 2013 08:29:55 GMT", "version": "v2" }, { "created": "Mon, 8 Jul 2013 17:41:49 GMT", "version": "v3" } ]
2013-07-09
[ [ "Busoni", "Giorgio", "" ], [ "De Simone", "Andrea", "" ], [ "Huang", "Wei-Chih", "" ] ]
We discuss a limitation on extracting bounds on the scattering cross section of dark matter with nucleons, using neutrinos from the Sun. If the dark matter particle is sufficiently light (less than about 4 GeV), the effect of evaporation is not negligible and the capture process goes in equilibrium with the evaporation. In this regime, the flux of solar neutrinos of dark matter origin becomes independent of the scattering cross section and therefore no constraint can be placed on it. We find the minimum values of dark matter masses for which the scattering cross section on nucleons can be probed using neutrinos from the Sun. We also provide simple and accurate fitting functions for all the relevant processes of GeV-scale dark matter in the Sun.
1207.5787
Joshua T. Ruderman
Joshua T. Ruderman, Tracy R. Slatyer, Neal Weiner
A Collective Breaking of R-Parity
28 pages, 10 figures
null
10.1007/JHEP09(2013)094
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supersymmetric theories with an R-parity generally yield a striking missing energy signature, with cascade decays concluding in a neutralino that escapes the detector. In theories where R-parity is broken the missing energy is replaced with additional jets or leptons, often making traditional search strategies ineffective. Such R-parity violation is very constrained, however, by resulting B and L violating signals, requiring couplings so small that LSPs will decay outside the detector in all but a few scenarios. In theories with additional matter fields, R-parity can be broken collectively, such that R-parity is not broken by any single coupling, but only by an ensemble of couplings. Cascade decays can proceed normally, with each step only sensitive to one or two couplings at a time, but B and L violation requires the full set, yielding a highly suppressed constraint. s-channel production of new scalar states, typically small for standard RPV, can be large when RPV is broken collectively. While missing energy is absent, making these models difficult to discover by traditional SUSY searches, they produce complicated many object resonances (MORes), with many different possible numbers of jets and leptons. We outline a simple model and discuss its discoverability at the LHC.
[ { "created": "Tue, 24 Jul 2012 19:59:19 GMT", "version": "v1" } ]
2015-06-05
[ [ "Ruderman", "Joshua T.", "" ], [ "Slatyer", "Tracy R.", "" ], [ "Weiner", "Neal", "" ] ]
Supersymmetric theories with an R-parity generally yield a striking missing energy signature, with cascade decays concluding in a neutralino that escapes the detector. In theories where R-parity is broken the missing energy is replaced with additional jets or leptons, often making traditional search strategies ineffective. Such R-parity violation is very constrained, however, by resulting B and L violating signals, requiring couplings so small that LSPs will decay outside the detector in all but a few scenarios. In theories with additional matter fields, R-parity can be broken collectively, such that R-parity is not broken by any single coupling, but only by an ensemble of couplings. Cascade decays can proceed normally, with each step only sensitive to one or two couplings at a time, but B and L violation requires the full set, yielding a highly suppressed constraint. s-channel production of new scalar states, typically small for standard RPV, can be large when RPV is broken collectively. While missing energy is absent, making these models difficult to discover by traditional SUSY searches, they produce complicated many object resonances (MORes), with many different possible numbers of jets and leptons. We outline a simple model and discuss its discoverability at the LHC.
1506.03996
Mohammad Rahim Talebtash
Mohammad Rahim Talebtash, Hossein Mehraban
Non-resonant four-body decay of $B \to D^- \pi^+\pi^+\pi^- $
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the branching ratio of the non-resonant $B \to D^- \pi^+\pi^+\pi^- $ decay using a simple model based on the framework of the factorization approach. In naive factorization approach, there are only tow tree diagrams for this decay mode. In the first diagram, the matrix element of decay mode is factorized into a $B\to D$ form factor multiplied by a $3\pi$ decay constant and in the second diagram, the matrix element is factorized into a $B\to D\pi$ form factor multiplied by a $2\pi$ decay constant, We assume that in the rest frame of B meson, the $D$ meson remains stationary, so we obtain the value $(3.47\pm0.14)\times 10^{-3}$ for the branching ration of the $B \to D^- \pi^+\pi^+\pi^- $ decay mode, while the experimental results are $(3.9\pm1.9)\times10^{-3}$.
[ { "created": "Fri, 12 Jun 2015 11:53:26 GMT", "version": "v1" }, { "created": "Mon, 7 Dec 2015 13:18:41 GMT", "version": "v2" } ]
2015-12-08
[ [ "Talebtash", "Mohammad Rahim", "" ], [ "Mehraban", "Hossein", "" ] ]
We calculate the branching ratio of the non-resonant $B \to D^- \pi^+\pi^+\pi^- $ decay using a simple model based on the framework of the factorization approach. In naive factorization approach, there are only tow tree diagrams for this decay mode. In the first diagram, the matrix element of decay mode is factorized into a $B\to D$ form factor multiplied by a $3\pi$ decay constant and in the second diagram, the matrix element is factorized into a $B\to D\pi$ form factor multiplied by a $2\pi$ decay constant, We assume that in the rest frame of B meson, the $D$ meson remains stationary, so we obtain the value $(3.47\pm0.14)\times 10^{-3}$ for the branching ration of the $B \to D^- \pi^+\pi^+\pi^- $ decay mode, while the experimental results are $(3.9\pm1.9)\times10^{-3}$.
1807.00530
Junmou Chen
Junmou Chen, Pyungwon Ko, Hsiang-nan Li, Jinmian Li, Hiroshi Yokoya
Light Dark Matter Showering under Broken Dark $U(1)$ -- Revisited
18 pages, 6 figures
null
10.1007/JHEP01(2019)141
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It was proposed recently that different chiralities of the dark matter (DM) fermion under a broken dark U(1) gauge group can lead to distinguishable signatures at the LHC through shower patterns, which may reveal the mass origin of the dark sector. We study this subject further by examining the dark shower of two simplified models, the dubbed Chiral Model and the Vector Model. We derive a more complete set of collinear splitting functions with power corrections, specifying the helicities of the initial DM fermion and including the contribution from an extra degree of freedom, the dark Higgs boson. The dark shower is then implemented with these splitting functions, and the new features resulting from its correct modelling are emphasized. It is shown that the DM fermion chirality can be differentiated by measuring dark shower patterns, especially the DM jet energy profile, which is almost independent of the DM energy.
[ { "created": "Mon, 2 Jul 2018 08:38:09 GMT", "version": "v1" }, { "created": "Tue, 3 Jul 2018 08:54:37 GMT", "version": "v2" }, { "created": "Mon, 19 Nov 2018 11:28:15 GMT", "version": "v3" } ]
2019-02-20
[ [ "Chen", "Junmou", "" ], [ "Ko", "Pyungwon", "" ], [ "Li", "Hsiang-nan", "" ], [ "Li", "Jinmian", "" ], [ "Yokoya", "Hiroshi", "" ] ]
It was proposed recently that different chiralities of the dark matter (DM) fermion under a broken dark U(1) gauge group can lead to distinguishable signatures at the LHC through shower patterns, which may reveal the mass origin of the dark sector. We study this subject further by examining the dark shower of two simplified models, the dubbed Chiral Model and the Vector Model. We derive a more complete set of collinear splitting functions with power corrections, specifying the helicities of the initial DM fermion and including the contribution from an extra degree of freedom, the dark Higgs boson. The dark shower is then implemented with these splitting functions, and the new features resulting from its correct modelling are emphasized. It is shown that the DM fermion chirality can be differentiated by measuring dark shower patterns, especially the DM jet energy profile, which is almost independent of the DM energy.
1807.10273
Gauthier Durieux
Gauthier Durieux and Oleksii Matsedonskyi
The top-quark window on compositeness at future lepton colliders
20 pages, 2 figures, 3 tables
null
10.1007/JHEP01(2019)072
DESY 18-114
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
In composite Higgs (CH) models, large mixings between the top quark and the new strongly interacting sector are required to generate its sizeable Yukawa coupling. Precise measurements involving top as well as left-handed bottom quarks therefore offer an interesting opportunity to probe such new physics scenarios. We study the impact of third-generation-quark pair production at future lepton colliders, translating prospective effective-field-theory sensitivities into the CH parameter space. Our results show that one can probe a significant fraction of the natural CH parameter space through the top portal, especially at TeV centre-of-mass energies.
[ { "created": "Thu, 26 Jul 2018 17:59:00 GMT", "version": "v1" } ]
2019-01-30
[ [ "Durieux", "Gauthier", "" ], [ "Matsedonskyi", "Oleksii", "" ] ]
In composite Higgs (CH) models, large mixings between the top quark and the new strongly interacting sector are required to generate its sizeable Yukawa coupling. Precise measurements involving top as well as left-handed bottom quarks therefore offer an interesting opportunity to probe such new physics scenarios. We study the impact of third-generation-quark pair production at future lepton colliders, translating prospective effective-field-theory sensitivities into the CH parameter space. Our results show that one can probe a significant fraction of the natural CH parameter space through the top portal, especially at TeV centre-of-mass energies.
1012.1093
Tillmann Heidsieck
Tillmann Heidsieck
Flavour physics with a 4th generation
Based on a talk given at the 6th International Workshop on the CKM Unitarity Triangle, Warwick, England, September 6th - 10th, 2010
null
null
TUM-HEP-784/10
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an overview of recent work on flavour physics in the presence of a sequential fourth generation. We will discuss shortly the constraints on the new parameters and in the reminder present predictions for observables like Br(B_s -> mu+ mu-), Br(K -> pi nu nubar) and the indirect CP violation S(psi phi) in the B_s system. We will further stress the importance of epsilon'/epsilon as a possible constraint once reliable lattice results for B_6 and B_8 become available. Lepton flavour violation is also briefly discussed in view of prospects for tau physics at an upgraded flavour factory as well as upcoming experiments for mu -> e gamma and mu-e conversion in nuclei.
[ { "created": "Mon, 6 Dec 2010 08:38:28 GMT", "version": "v1" } ]
2010-12-07
[ [ "Heidsieck", "Tillmann", "" ] ]
We present an overview of recent work on flavour physics in the presence of a sequential fourth generation. We will discuss shortly the constraints on the new parameters and in the reminder present predictions for observables like Br(B_s -> mu+ mu-), Br(K -> pi nu nubar) and the indirect CP violation S(psi phi) in the B_s system. We will further stress the importance of epsilon'/epsilon as a possible constraint once reliable lattice results for B_6 and B_8 become available. Lepton flavour violation is also briefly discussed in view of prospects for tau physics at an upgraded flavour factory as well as upcoming experiments for mu -> e gamma and mu-e conversion in nuclei.
hep-ph/0510062
Carlos A. Salgado
Carlos A. Salgado
RHIC results from LHC perspectives
10 pages, 5 figures. Plenary talk given at Quark Matter 2005 Conference, Budapest, Hungary, 4-9 Aug 2005
Nucl.Phys. A774 (2006) 267-276
10.1016/j.nuclphysa.2006.06.047
CERN-PH-TH/2005-191
hep-ph
null
RHIC data opens new ways of characterizing the medium created in a heavy ion collision by measuring particles with high transverse momentum. In addition to the observation of the predicted jet quenching, the new data on particle correlations indicate that a strong modification of the jet-like shapes is driven by the dynamical properties of the medium. I will review the lessons we are learning from RHIC and outline some new directions which could become of primary importance at the LHC.
[ { "created": "Wed, 5 Oct 2005 17:32:41 GMT", "version": "v1" } ]
2009-11-11
[ [ "Salgado", "Carlos A.", "" ] ]
RHIC data opens new ways of characterizing the medium created in a heavy ion collision by measuring particles with high transverse momentum. In addition to the observation of the predicted jet quenching, the new data on particle correlations indicate that a strong modification of the jet-like shapes is driven by the dynamical properties of the medium. I will review the lessons we are learning from RHIC and outline some new directions which could become of primary importance at the LHC.
hep-ph/0111289
Daniele Fargion
Daniele Fargion
Upward and Horizontal Tau Airshowers by UHE Neutrinos
5 pages, 3 figures, HEP2001 Conference, 13 July,Budapest. Particle Astrophysics and Cosmology, 2001
Proceedings of the EPS International Conference on High Energy Physics, Budapest, 2001 (D. Horvath, P. Levai, A. Patkos,eds.), JHEP PrHEP-hep2001/208
null
null
hep-ph astro-ph quant-ph
null
Upward and Horizontal Tau Air-showers (UPTAUS and HORTAUS) emerging from the Earth crust, mountain chains or deep plate boundaries are the most powerful signals of Ultra High Energy UHE anti neutrinos electron at PeV and neutrino and anti-neutrino tau at energies near and above 10^15-10^19 eV. The large tau Air-showers multiplicity N in secondaries N_opt =10^12 E_tau/ PeV, N_gamma= 10^8 E_tau/PeV, N_{e^- e^+}= 2 10^7 E_tau/PeV, N_mu = 3 10^5 E_tau/PeV^{0.85}, make easy their discover. UHE nu_tau, nu_tau because neutrino flavor mixing, nu_mu <--> nu_tau, should be as abundant as nu_mu, bar-nu_mu. Also bar{nu}_e, near the Glashow W resonance peak, E_bar{nu_e}= M^2_W / 2m_e = 6.3 10^{15} eV, may generate tau Air-showers. The HORTAUS may test the UHE neutrino interactions leading to additional fine-tuned test of New TeV Physics in Mountain Valleys and Earth crust horizontal edges. UPTAUS or HORTAUS, beaming toward high mountains, air-planes, ballons and satellites should flash gamma, muon, X and Cherenkov lights toward detectors. Such UPTAUS might already hit nearby satellite GRO gamma detectors flashing it by short (millisecond), hard, diluted gamma-burst at the edge of BATSE threshold. We claimed their identity with the observed BATSE 78 Terrestrial Gamma Flashes (TGF). The TGF clustering toward Galactic Center and Plane, known AGNs source strongly support their UHE Tau neutrino origin.
[ { "created": "Thu, 22 Nov 2001 19:12:24 GMT", "version": "v1" }, { "created": "Sun, 2 Dec 2001 15:40:42 GMT", "version": "v2" } ]
2007-05-23
[ [ "Fargion", "Daniele", "" ] ]
Upward and Horizontal Tau Air-showers (UPTAUS and HORTAUS) emerging from the Earth crust, mountain chains or deep plate boundaries are the most powerful signals of Ultra High Energy UHE anti neutrinos electron at PeV and neutrino and anti-neutrino tau at energies near and above 10^15-10^19 eV. The large tau Air-showers multiplicity N in secondaries N_opt =10^12 E_tau/ PeV, N_gamma= 10^8 E_tau/PeV, N_{e^- e^+}= 2 10^7 E_tau/PeV, N_mu = 3 10^5 E_tau/PeV^{0.85}, make easy their discover. UHE nu_tau, nu_tau because neutrino flavor mixing, nu_mu <--> nu_tau, should be as abundant as nu_mu, bar-nu_mu. Also bar{nu}_e, near the Glashow W resonance peak, E_bar{nu_e}= M^2_W / 2m_e = 6.3 10^{15} eV, may generate tau Air-showers. The HORTAUS may test the UHE neutrino interactions leading to additional fine-tuned test of New TeV Physics in Mountain Valleys and Earth crust horizontal edges. UPTAUS or HORTAUS, beaming toward high mountains, air-planes, ballons and satellites should flash gamma, muon, X and Cherenkov lights toward detectors. Such UPTAUS might already hit nearby satellite GRO gamma detectors flashing it by short (millisecond), hard, diluted gamma-burst at the edge of BATSE threshold. We claimed their identity with the observed BATSE 78 Terrestrial Gamma Flashes (TGF). The TGF clustering toward Galactic Center and Plane, known AGNs source strongly support their UHE Tau neutrino origin.
1902.03231
Carlota Andres
Carlota Andres, N\'estor Armesto, Harri Niemi, Risto Paatelainen and Carlos A. Salgado
Jet quenching as a probe of the initial stages in heavy-ion collisions
10 pages, 7 figures. Version to be published in PLB. Minor changes in the text and a new appendix containing 4 additional figures added
Phys. Lett. B 803 (2020) 135318
10.1016/j.physletb.2020.135318
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Jet quenching provides a very flexible variety of observables which are sensitive to different energy- and time-scales of the strongly interacting matter created in heavy-ion collisions. Exploiting this versatility would make jet quenching an excellent chronometer of the yoctosecond structure of the evolution process. Here we show, for the first time, that a combination of jet quenching observables is sensitive to the initial stages of heavy-ion collisions, when the approach to local thermal equilibrium is expected to happen. Specifically, we find that in order to reproduce at the same time the inclusive particle production suppression, $R_{AA}$, and the high-$p_T$ azimuthal asymmetries, $v_2$, energy loss must be strongly suppressed for the first $\sim 0.6$ fm. This exploratory analysis shows the potential of jet observables, possibly more sophisticated than the ones studied here, to constrain the dynamics of the initial stages of the evolution.
[ { "created": "Fri, 8 Feb 2019 18:47:08 GMT", "version": "v1" }, { "created": "Wed, 26 Feb 2020 23:32:27 GMT", "version": "v2" } ]
2020-03-02
[ [ "Andres", "Carlota", "" ], [ "Armesto", "Néstor", "" ], [ "Niemi", "Harri", "" ], [ "Paatelainen", "Risto", "" ], [ "Salgado", "Carlos A.", "" ] ]
Jet quenching provides a very flexible variety of observables which are sensitive to different energy- and time-scales of the strongly interacting matter created in heavy-ion collisions. Exploiting this versatility would make jet quenching an excellent chronometer of the yoctosecond structure of the evolution process. Here we show, for the first time, that a combination of jet quenching observables is sensitive to the initial stages of heavy-ion collisions, when the approach to local thermal equilibrium is expected to happen. Specifically, we find that in order to reproduce at the same time the inclusive particle production suppression, $R_{AA}$, and the high-$p_T$ azimuthal asymmetries, $v_2$, energy loss must be strongly suppressed for the first $\sim 0.6$ fm. This exploratory analysis shows the potential of jet observables, possibly more sophisticated than the ones studied here, to constrain the dynamics of the initial stages of the evolution.
1810.05149
Marc Montull
Christophe Grojean, Marc Montull, Marc Riembau
Diboson at the LHC vs LEP
45 pages, 17 figures. v2: published version, expanded discussion on UV models, additional plots to compare relative importance of WW and WZ channels
null
10.1007/JHEP03(2019)020
DESY 17-231
hep-ph
http://creativecommons.org/licenses/by/4.0/
We use the current CMS and ATLAS data for the leptonic $pp \to WW, WZ$ channels to show that diboson production is, for a broad class of flavour models, already competitive with LEP-1 measurements for setting bounds on the dimension six operators parametrising the anomalous couplings between the quarks and the electroweak gauge bosons, at least under the assumption that any new particle is heavier than a few TeV. We also make an estimate of the HL-LHC reach with $3$ ab$^{-1}$. We comment on possible BSM interpretations of the bounds, and show the interplay with other searches for a simplified model with vector triplets. We further study the effect of modified $Z$-quark-quark couplings on the anomalous triple gauge coupling bounds. We find that their impact is already significant and that it could modify the constraints on $\delta g_{1z}$ and $\delta \kappa_\gamma$ by as much as a factor two at the end of HL-LHC ($\lambda_\gamma$ is only marginally affected), requiring a global fit to extract robust bounds. We stress the role of flavour assumptions and study explicitly flavour universal and minimal flavour violation scenarios, illustrating the differences with results obtained for universal theories.
[ { "created": "Thu, 11 Oct 2018 17:49:50 GMT", "version": "v1" }, { "created": "Fri, 8 Mar 2019 16:41:47 GMT", "version": "v2" } ]
2019-03-27
[ [ "Grojean", "Christophe", "" ], [ "Montull", "Marc", "" ], [ "Riembau", "Marc", "" ] ]
We use the current CMS and ATLAS data for the leptonic $pp \to WW, WZ$ channels to show that diboson production is, for a broad class of flavour models, already competitive with LEP-1 measurements for setting bounds on the dimension six operators parametrising the anomalous couplings between the quarks and the electroweak gauge bosons, at least under the assumption that any new particle is heavier than a few TeV. We also make an estimate of the HL-LHC reach with $3$ ab$^{-1}$. We comment on possible BSM interpretations of the bounds, and show the interplay with other searches for a simplified model with vector triplets. We further study the effect of modified $Z$-quark-quark couplings on the anomalous triple gauge coupling bounds. We find that their impact is already significant and that it could modify the constraints on $\delta g_{1z}$ and $\delta \kappa_\gamma$ by as much as a factor two at the end of HL-LHC ($\lambda_\gamma$ is only marginally affected), requiring a global fit to extract robust bounds. We stress the role of flavour assumptions and study explicitly flavour universal and minimal flavour violation scenarios, illustrating the differences with results obtained for universal theories.
2208.05064
Ricardo S\'anchez-V\'elez
A. Bola\~nos-Carrera, R. S\'anchez-V\'elez and G. Tavares-Velasco
Rare decay $t\to c\gamma\gamma$ via scalar leptoquark doublets
In preparation for Journal Submission
null
10.1103/PhysRevD.107.095018
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A calculation of the one-loop contribution to the rare three-body flavor changing neutral current top quark decay $t\to c\gamma\gamma$ is presented in the framework of models with one or more scalar leptoquark $SU(2)$ doublets with hypercharge $7/6$. Analytical expressions for the invariant amplitude of the generic decay $f_i\to f_j\gamma\gamma$, with $f_{i,j}$ a lepton or quark, are presented in terms of Passarino-Veltman integral coefficients, from which the amplitudes for the processes $t\to c\gamma\gamma$ and $\ell_i\to \ell_j\gamma\gamma$ follow easily. An analysis of the current constraints on the parameter space is presented in the scenario with only one scalar LQ doublet and bounds on the LQ couplings are obtained from the muon $g-2$ anomaly, the lepton flavor violating (LFV) decay $\tau\to \mu\gamma$ and extra constraints meant to avoid tension between theory predictions and experimental data. For a LQ with a mass in the range of $1$--$1.5$ TeVs, the estimate ${\rm Br}(t\to c\gamma\gamma)\sim 10^{-11}$--$10^{-12}$ is obtained for the largest allowed values of the LQ coupling constants, which means that this decay would be below the reach of future experimental measurements. We also consider an scenario with three scalar doublets, which was recently proposed to explain the lepton flavor universality violation anomalies in $B$ decays as well as the muon $g-2$ anomaly. Although this scenario allows large LQ couplings to the tau lepton and the $c$ and $t$ quarks, the branching ratio of the $t\to c\gamma\gamma$ decay is also of the order of $10^{-11}$--$10^{-12}$ for LQ masses of 1.7 TeV.
[ { "created": "Tue, 9 Aug 2022 22:40:58 GMT", "version": "v1" }, { "created": "Fri, 9 Dec 2022 19:17:37 GMT", "version": "v2" }, { "created": "Tue, 4 Apr 2023 06:42:48 GMT", "version": "v3" } ]
2023-05-24
[ [ "Bolaños-Carrera", "A.", "" ], [ "Sánchez-Vélez", "R.", "" ], [ "Tavares-Velasco", "G.", "" ] ]
A calculation of the one-loop contribution to the rare three-body flavor changing neutral current top quark decay $t\to c\gamma\gamma$ is presented in the framework of models with one or more scalar leptoquark $SU(2)$ doublets with hypercharge $7/6$. Analytical expressions for the invariant amplitude of the generic decay $f_i\to f_j\gamma\gamma$, with $f_{i,j}$ a lepton or quark, are presented in terms of Passarino-Veltman integral coefficients, from which the amplitudes for the processes $t\to c\gamma\gamma$ and $\ell_i\to \ell_j\gamma\gamma$ follow easily. An analysis of the current constraints on the parameter space is presented in the scenario with only one scalar LQ doublet and bounds on the LQ couplings are obtained from the muon $g-2$ anomaly, the lepton flavor violating (LFV) decay $\tau\to \mu\gamma$ and extra constraints meant to avoid tension between theory predictions and experimental data. For a LQ with a mass in the range of $1$--$1.5$ TeVs, the estimate ${\rm Br}(t\to c\gamma\gamma)\sim 10^{-11}$--$10^{-12}$ is obtained for the largest allowed values of the LQ coupling constants, which means that this decay would be below the reach of future experimental measurements. We also consider an scenario with three scalar doublets, which was recently proposed to explain the lepton flavor universality violation anomalies in $B$ decays as well as the muon $g-2$ anomaly. Although this scenario allows large LQ couplings to the tau lepton and the $c$ and $t$ quarks, the branching ratio of the $t\to c\gamma\gamma$ decay is also of the order of $10^{-11}$--$10^{-12}$ for LQ masses of 1.7 TeV.
0911.4096
Matti Jarvinen
Matti Jarvinen, Chris Kouvaris, Francesco Sannino
Gravitational Techniwaves
30 pages, 5 figures. v2: minor changes, references added, title changed in journal
Phys.Rev.D81:064027,2010
10.1103/PhysRevD.81.064027
CP3-Origins-2009-24
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the production and possible detection of gravitational waves stemming from the electroweak phase transition in the early universe in models of minimal walking technicolor. In particular we discuss the two possible scenarios in which one has only one electroweak phase transition and the case in which the technicolor dynamics allows for multiple phase transitions.
[ { "created": "Fri, 20 Nov 2009 18:52:07 GMT", "version": "v1" }, { "created": "Thu, 8 Apr 2010 17:40:01 GMT", "version": "v2" } ]
2010-04-14
[ [ "Jarvinen", "Matti", "" ], [ "Kouvaris", "Chris", "" ], [ "Sannino", "Francesco", "" ] ]
We investigate the production and possible detection of gravitational waves stemming from the electroweak phase transition in the early universe in models of minimal walking technicolor. In particular we discuss the two possible scenarios in which one has only one electroweak phase transition and the case in which the technicolor dynamics allows for multiple phase transitions.
2303.09566
Julian Heeck
Julian Heeck and Mikheil Sokhashvili
Revisiting the Friedberg-Lee-Sirlin soliton model
9 pages, matches EPJC version
Eur. Phys. J. C 83, 526 (2023)
10.1140/epjc/s10052-023-11710-9
null
hep-ph hep-th nlin.SI
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Non-topological solitons are localized classical field configurations stabilized by a Noether charge. Friedberg, Lee, and Sirlin proposed a simple renormalizable soliton model in their seminal 1976 paper, consisting of a complex scalar field that carries the Noether charge and a real-scalar mediator. We revisit this model, point out commonalities and differences with Q-ball solitons, and provide analytic approximations to the underlying differential equations.
[ { "created": "Thu, 16 Mar 2023 18:00:00 GMT", "version": "v1" }, { "created": "Thu, 22 Jun 2023 18:43:30 GMT", "version": "v2" } ]
2023-06-26
[ [ "Heeck", "Julian", "" ], [ "Sokhashvili", "Mikheil", "" ] ]
Non-topological solitons are localized classical field configurations stabilized by a Noether charge. Friedberg, Lee, and Sirlin proposed a simple renormalizable soliton model in their seminal 1976 paper, consisting of a complex scalar field that carries the Noether charge and a real-scalar mediator. We revisit this model, point out commonalities and differences with Q-ball solitons, and provide analytic approximations to the underlying differential equations.
1212.5427
Antoni Szczurek
Antoni Szczurek and Rafal Maciula
Production of one and two $c \bar c$ pairs at LHC
5 pages, 4 figures, invited talk by A. Szczurek at the international workshop Diffraction2012, Puerto del Carmen, Lanzarote, Spain, September 10-15, 2012
null
10.1063/1.4802161
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on charm production at LHC. The production of single $c \bar c$ pairs is calculated in the $k_t$-factorization approach with different unintegrated gluon distributions. Examples of transverse momentum distributions for charmed mesons are presented and compared to recent experimental results from LHC. Some missing strength is observed for most of UGDFs. Furthermore we discuss production of two $c \bar c$ pairs within double-parton scattering (DPS) and single-parton scattering (SPS) mechanisms. Surprisingly large cross sections, comparable to single $c \bar c$ pair production are predicted. We discuss first experimental results from LHCb collaboration on production of pairs of $D$ mesons of the same flavour.
[ { "created": "Fri, 21 Dec 2012 13:37:39 GMT", "version": "v1" } ]
2015-06-12
[ [ "Szczurek", "Antoni", "" ], [ "Maciula", "Rafal", "" ] ]
We report on charm production at LHC. The production of single $c \bar c$ pairs is calculated in the $k_t$-factorization approach with different unintegrated gluon distributions. Examples of transverse momentum distributions for charmed mesons are presented and compared to recent experimental results from LHC. Some missing strength is observed for most of UGDFs. Furthermore we discuss production of two $c \bar c$ pairs within double-parton scattering (DPS) and single-parton scattering (SPS) mechanisms. Surprisingly large cross sections, comparable to single $c \bar c$ pair production are predicted. We discuss first experimental results from LHCb collaboration on production of pairs of $D$ mesons of the same flavour.
0911.4764
Daniel Hern\'andez
D. Hernandez
Non-standard Neutrino Interactions
Proceedings of the 44th Rencontres de Moriond on Electroweak Interactions and Unified Theories
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Theories beyond the Standard Model must respect its gauge symmetry. This implies strict constraints on the possible models of Non-Standard Neutrino Interactions (NSIs). We review here the present status of NSIs from the point of view of effective field theory. Our recent work on the restrictions implied by Standard Model gauge invariance is provided along with some examples of possible gauge invariant models featuring non-standard interactions.
[ { "created": "Wed, 25 Nov 2009 05:25:59 GMT", "version": "v1" } ]
2009-11-26
[ [ "Hernandez", "D.", "" ] ]
Theories beyond the Standard Model must respect its gauge symmetry. This implies strict constraints on the possible models of Non-Standard Neutrino Interactions (NSIs). We review here the present status of NSIs from the point of view of effective field theory. Our recent work on the restrictions implied by Standard Model gauge invariance is provided along with some examples of possible gauge invariant models featuring non-standard interactions.
1208.4623
Mariola Klusek-Gawenda
Mariola Klusek-Gawenda, Antoni Szczurek
Exclusive production of $\pi^+\pi^-$ and $\pi^0\pi^0$ pairs in photon-photon and in ultrarelativistic heavy ion collisions
4 pages, 7 figures, 1 table, talk by M. Klusek-Gawenda at MESON2012, 31 May - 5 June 2012, Krakow, Poland
null
10.1051/epjconf/20123706006
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The $\gamma\gamma\to\pi\pi$ reactions are discussed. To describe those processes, we include dipion continuum, resonances, high-energy pion-pion rescatterings, $\rho$ meson exchange and pQCD Brodsky-Lepage mechanisms. The cross section for the production of pion pairs in photon-photon collisions in peripheral heavy ion collisions is calculated with the help of Equivalent Photon Approximaption (EPA) in the impact parameter space. We show predictions at $\sqrt{s_{NN}}=3.5$ TeV which could be measured e.g. by the ALICE collaboration at the LHC.
[ { "created": "Wed, 22 Aug 2012 20:53:58 GMT", "version": "v1" } ]
2017-08-23
[ [ "Klusek-Gawenda", "Mariola", "" ], [ "Szczurek", "Antoni", "" ] ]
The $\gamma\gamma\to\pi\pi$ reactions are discussed. To describe those processes, we include dipion continuum, resonances, high-energy pion-pion rescatterings, $\rho$ meson exchange and pQCD Brodsky-Lepage mechanisms. The cross section for the production of pion pairs in photon-photon collisions in peripheral heavy ion collisions is calculated with the help of Equivalent Photon Approximaption (EPA) in the impact parameter space. We show predictions at $\sqrt{s_{NN}}=3.5$ TeV which could be measured e.g. by the ALICE collaboration at the LHC.
1606.05163
Ivica Picek
Oleg Antipin, Petar Culjak, Kresimir Kumericki and Ivica Picek
Radiative neutrino models in light of diphoton signals
23 pages, 5 figures, new section and refs added; to stay unpublished since diphoton signal disappeared
null
null
ZTF-EP-16-02
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Viable explanations of a hinted 750 GeV scalar resonance may be sought within the extensions of the SM Higgs sector aimed at generating neutrino masses at the loop level. We confront a compatibility with the 750 GeV diphoton excess for two recent models which do not need to impose ad hoc symmetry to forbid the tree-level masses: a one-loop mass model providing the H(750) candidate within its real triplet scalar representation and a three-loop mass model providing it within its two Higgs doublets. Besides accounting for the 750 GeV resonance, we demonstrate that these complementary neutrino-mass scenarios have different testable predictions for the LHC which should show up soon as more data is accumulated during the ongoing 13 TeV run.
[ { "created": "Thu, 16 Jun 2016 12:45:00 GMT", "version": "v1" }, { "created": "Wed, 25 Jan 2017 12:40:15 GMT", "version": "v2" } ]
2017-01-26
[ [ "Antipin", "Oleg", "" ], [ "Culjak", "Petar", "" ], [ "Kumericki", "Kresimir", "" ], [ "Picek", "Ivica", "" ] ]
Viable explanations of a hinted 750 GeV scalar resonance may be sought within the extensions of the SM Higgs sector aimed at generating neutrino masses at the loop level. We confront a compatibility with the 750 GeV diphoton excess for two recent models which do not need to impose ad hoc symmetry to forbid the tree-level masses: a one-loop mass model providing the H(750) candidate within its real triplet scalar representation and a three-loop mass model providing it within its two Higgs doublets. Besides accounting for the 750 GeV resonance, we demonstrate that these complementary neutrino-mass scenarios have different testable predictions for the LHC which should show up soon as more data is accumulated during the ongoing 13 TeV run.
1309.5412
Jeronimo Peralta Ramos
E. Calzetta, J. Peralta-Ramos
A hydrodynamic approach to QGP instabilities
11 pages, no figures. v2: minor changes, added references. Accepted in Phys. Rev. D
null
10.1103/PhysRevD.88.095010
null
hep-ph physics.plasm-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that the usual linear analysis of QGP Weibel instabilities based on the Maxwell-Boltzmann equation may be reproduced in a purely hydrodynamic model. The latter is derived by the Entropy Production Variational Method from a transport equation including collisions, and can describe highly nonequilibrium flow. We find that, as expected, collisions slow down the growth of Weibel instabilities. Finally, we discuss the strong momentum anisotropy limit.
[ { "created": "Fri, 20 Sep 2013 23:28:57 GMT", "version": "v1" }, { "created": "Mon, 4 Nov 2013 20:59:26 GMT", "version": "v2" } ]
2015-06-17
[ [ "Calzetta", "E.", "" ], [ "Peralta-Ramos", "J.", "" ] ]
We show that the usual linear analysis of QGP Weibel instabilities based on the Maxwell-Boltzmann equation may be reproduced in a purely hydrodynamic model. The latter is derived by the Entropy Production Variational Method from a transport equation including collisions, and can describe highly nonequilibrium flow. We find that, as expected, collisions slow down the growth of Weibel instabilities. Finally, we discuss the strong momentum anisotropy limit.
hep-ph/9903418
Sourov Roy
Biswarup Mukhopadhyaya and Sourov Roy
Radiative decay of the lightest neutralino in an R-parity violating supersymmetric theory
25 pages, LaTex including postscript figures. Uses axodraw.sty. Minor typographic errors corrected
Phys.Rev. D60 (1999) 115012
10.1103/PhysRevD.60.115012
MRI-PHY/P990307
hep-ph
null
In an R-parity violating supersymmetric scenario, the lightest neutralino $\tilde \chi^0_1$ is no longer a stable particle. We calculate the branching ratio for the decay mode $\tilde \chi^0_1 \longrightarrow \nu \gamma$ which occurs at the one-loop level. Taking into account bilinear as well as trilinear lepton number violating interactions as the sources of R-parity violation, we make a detailed scan of the parameter space, both with and without gaugino mass unification and including the constraints on the neutrino sector from the recent Superkamiokande results. This study enables one to suggest interesting experimental signals distinguishing between the two types of R-parity breaking, and also to ascertain whether such radiative decays can give rise to collider signals of the type $\gamma \gamma$ + $\not {\rm E}$ from pair-produced neutralinos.
[ { "created": "Sat, 20 Mar 1999 12:29:34 GMT", "version": "v1" }, { "created": "Fri, 6 Aug 1999 00:46:35 GMT", "version": "v2" } ]
2009-10-31
[ [ "Mukhopadhyaya", "Biswarup", "" ], [ "Roy", "Sourov", "" ] ]
In an R-parity violating supersymmetric scenario, the lightest neutralino $\tilde \chi^0_1$ is no longer a stable particle. We calculate the branching ratio for the decay mode $\tilde \chi^0_1 \longrightarrow \nu \gamma$ which occurs at the one-loop level. Taking into account bilinear as well as trilinear lepton number violating interactions as the sources of R-parity violation, we make a detailed scan of the parameter space, both with and without gaugino mass unification and including the constraints on the neutrino sector from the recent Superkamiokande results. This study enables one to suggest interesting experimental signals distinguishing between the two types of R-parity breaking, and also to ascertain whether such radiative decays can give rise to collider signals of the type $\gamma \gamma$ + $\not {\rm E}$ from pair-produced neutralinos.
1201.0149
Ju-Jun Xie
Ju-Jun Xie and E. Oset
The $DN$, $\pi \Sigma_c$ interaction in finite volume and the $\Lambda_c(2595)$ resonance
10 pages, 13 figures, accepted for publication in Eur. Phys. J. A
null
10.1140/epja/i2012-12146-x
null
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work the interaction of the coupled channels $DN$ and $\pi \Sigma_c$ in an SU(4) extrapolation of the chiral unitary theory, where the $\Lambda_c(2595)$ resonance appears as dynamically generated from that interaction, is extended to produce results in finite volume. Energy levels in the finite box are evaluated and, assuming that they would correspond to lattice results, the inverse problem of determining the phase shifts in the infinite volume from the lattice results is solved. We observe that it is possible to obtain accurate $\pi \Sigma_c$ phase shifts and the position of the $\Lambda_c(2595)$ resonance, but it requires the explicit consideration of the two coupled channels. We also observe that some of the energy levels in the box are attached to the closed $DN$ channel, such that their use to induce the $\pi \Sigma_c$ phase shifts via L\"uscher's formula leads to incorrect results.
[ { "created": "Fri, 30 Dec 2011 16:19:19 GMT", "version": "v1" }, { "created": "Tue, 25 Sep 2012 08:21:56 GMT", "version": "v2" } ]
2015-06-03
[ [ "Xie", "Ju-Jun", "" ], [ "Oset", "E.", "" ] ]
In this work the interaction of the coupled channels $DN$ and $\pi \Sigma_c$ in an SU(4) extrapolation of the chiral unitary theory, where the $\Lambda_c(2595)$ resonance appears as dynamically generated from that interaction, is extended to produce results in finite volume. Energy levels in the finite box are evaluated and, assuming that they would correspond to lattice results, the inverse problem of determining the phase shifts in the infinite volume from the lattice results is solved. We observe that it is possible to obtain accurate $\pi \Sigma_c$ phase shifts and the position of the $\Lambda_c(2595)$ resonance, but it requires the explicit consideration of the two coupled channels. We also observe that some of the energy levels in the box are attached to the closed $DN$ channel, such that their use to induce the $\pi \Sigma_c$ phase shifts via L\"uscher's formula leads to incorrect results.
2401.07289
Yan Wang
Yan Ma, A. Arhrib, S. Moretti, S. Semlali, Y. Wang, Q.S. Yan
Analysis of the $gg\to H\to hh\to4\tau$ process in the 2HDM lepton specific model at the LHC
19 pages, 7 figures, 7 tables. arXiv admin note: text overlap with arXiv:2305.05788
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We analyse the signature of a light Higgs boson pair in the 2-Higgs Doublet Model(2HDM) Type-X (or lepton specific) over the parameter spaces allowed by theoretical self-consistency requirements as well as the latest experimental constraints from the Large Hadron Collider (LHC), precision test data and $B$ physics. Over the viable regions of the latter, wherein the Standard Model (SM)-like Higgs boson discovered at the LHC in 2012 is the heavier CP-even state of the 2HDM, $H$, it is found that the SM-like Higgs boson can decay into a pair of the lighter CP-even Higgs boson, $h$, via the process $H\to hh$ with a Branching Ratio (BR) of $5\%-10\%$ or so, (with $2 m_h < m_H =125$ GeV). Furthermore, in the Type-X scenario, the lighter Higgs bosons $h$ can dominantly decay into two $\tau$'s due to a large $\tan\beta$. Therefore, the pair of lighter Higgs bosons can altogether decay into a 4 $\tau$ final state. In order to suppress the huge SM background events, we confine ourself to consider the fraction of signal events with two Same-Sign (SS) $\tau$'s further decaying into same sign leptons while the other two $\tau$'s decay hadronically. By using Monte Carlo (MC) and Machine Learning (ML) tools, we thus focus on the analysis of the signal process $pp\to H\to hh\to \tau^{+}\tau^{-}\tau^{+}\tau^{-}\to \ell v_\ell \ell v_\ell \tau_h \tau_h$ (where $\ell= e, \mu$ and $\tau_h$ means a hadronic decay of the $\tau$) and explore the feasibility of such a search at the LHC for a collision energy $\sqrt{s}=~\text{14 TeV}$ and a luminosity $\text{300}~\text{fb}^{-1}$
[ { "created": "Sun, 14 Jan 2024 13:46:24 GMT", "version": "v1" } ]
2024-01-17
[ [ "Ma", "Yan", "" ], [ "Arhrib", "A.", "" ], [ "Moretti", "S.", "" ], [ "Semlali", "S.", "" ], [ "Wang", "Y.", "" ], [ "Yan", "Q. S.", "" ] ]
We analyse the signature of a light Higgs boson pair in the 2-Higgs Doublet Model(2HDM) Type-X (or lepton specific) over the parameter spaces allowed by theoretical self-consistency requirements as well as the latest experimental constraints from the Large Hadron Collider (LHC), precision test data and $B$ physics. Over the viable regions of the latter, wherein the Standard Model (SM)-like Higgs boson discovered at the LHC in 2012 is the heavier CP-even state of the 2HDM, $H$, it is found that the SM-like Higgs boson can decay into a pair of the lighter CP-even Higgs boson, $h$, via the process $H\to hh$ with a Branching Ratio (BR) of $5\%-10\%$ or so, (with $2 m_h < m_H =125$ GeV). Furthermore, in the Type-X scenario, the lighter Higgs bosons $h$ can dominantly decay into two $\tau$'s due to a large $\tan\beta$. Therefore, the pair of lighter Higgs bosons can altogether decay into a 4 $\tau$ final state. In order to suppress the huge SM background events, we confine ourself to consider the fraction of signal events with two Same-Sign (SS) $\tau$'s further decaying into same sign leptons while the other two $\tau$'s decay hadronically. By using Monte Carlo (MC) and Machine Learning (ML) tools, we thus focus on the analysis of the signal process $pp\to H\to hh\to \tau^{+}\tau^{-}\tau^{+}\tau^{-}\to \ell v_\ell \ell v_\ell \tau_h \tau_h$ (where $\ell= e, \mu$ and $\tau_h$ means a hadronic decay of the $\tau$) and explore the feasibility of such a search at the LHC for a collision energy $\sqrt{s}=~\text{14 TeV}$ and a luminosity $\text{300}~\text{fb}^{-1}$
hep-ph/0302202
Jonathan Sapirstein
J. Sapirstein, K. Pachucki, A. Veitia, and K.T. Cheng
Radiative Corrections to Parity Nonconserving Transitions in Atoms
20 pages, 4 figures
null
10.1103/PhysRevA.67.052110
null
hep-ph
null
The matrix element of a bound electron interacting with the nucleus through exchange of a Z boson is studied for the gauge invariant case of $2s_{1/2}-2p_{1/2}$ transitions in hydrogenic ions. The QED radiative correction to the matrix element, which is $-\alpha/2\pi$ in lowest order, is calculated to all orders in $Z\alpha$ using exact propagators. Previous calculation of the first-order binding correction are confirmed both analytically and by fitting the exact function at low $Z$. Consequences for the interpretation of parity nonconservation in cesium are discussed.
[ { "created": "Sat, 22 Feb 2003 14:23:05 GMT", "version": "v1" } ]
2009-11-10
[ [ "Sapirstein", "J.", "" ], [ "Pachucki", "K.", "" ], [ "Veitia", "A.", "" ], [ "Cheng", "K. T.", "" ] ]
The matrix element of a bound electron interacting with the nucleus through exchange of a Z boson is studied for the gauge invariant case of $2s_{1/2}-2p_{1/2}$ transitions in hydrogenic ions. The QED radiative correction to the matrix element, which is $-\alpha/2\pi$ in lowest order, is calculated to all orders in $Z\alpha$ using exact propagators. Previous calculation of the first-order binding correction are confirmed both analytically and by fitting the exact function at low $Z$. Consequences for the interpretation of parity nonconservation in cesium are discussed.
2106.15522
Nikolaos Stefanis
S. V. Mikhailov and N. G. Stefanis
Cross-link relations between $\pi$ and $\rho$-meson channels and the QCD vacuum
9 pages, 1 table, 4 figures. V2 matches published version
Phys. Rev. D 104, 096103 (2021)
10.1103/PhysRevD.104.096013
RUB-TPII-02/2021
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss cross-link relations between the $\pi$ and $\rho$-meson channels emerging from two different descriptions of the QCD vacuum: Instanton physics and QCD sum rules with nonlocal condensates (NLC). We derive in both schemes an intriguing linear relation between the $\pi$ and the $\rho^\|$-meson distribution amplitudes in terms of their conformal coefficients and work out the specific impact of the scalar NLC in these two channels. Using a simple model with Gaussian decay of the scalar NLC, we are able to relate it to the moments of the pion non-singlet parton distribution function measurable in experiment -- a highly nontrivial result. The implications for the pion and the $\rho^\|$-meson DAs entailed by the obtained cross-link relations are outlined in terms of two generic scenarios.
[ { "created": "Tue, 29 Jun 2021 15:50:09 GMT", "version": "v1" }, { "created": "Mon, 22 Nov 2021 14:25:42 GMT", "version": "v2" } ]
2021-11-23
[ [ "Mikhailov", "S. V.", "" ], [ "Stefanis", "N. G.", "" ] ]
We discuss cross-link relations between the $\pi$ and $\rho$-meson channels emerging from two different descriptions of the QCD vacuum: Instanton physics and QCD sum rules with nonlocal condensates (NLC). We derive in both schemes an intriguing linear relation between the $\pi$ and the $\rho^\|$-meson distribution amplitudes in terms of their conformal coefficients and work out the specific impact of the scalar NLC in these two channels. Using a simple model with Gaussian decay of the scalar NLC, we are able to relate it to the moments of the pion non-singlet parton distribution function measurable in experiment -- a highly nontrivial result. The implications for the pion and the $\rho^\|$-meson DAs entailed by the obtained cross-link relations are outlined in terms of two generic scenarios.
1301.5970
Gulsheen Ahuja
Priyanka Fakay, Samandeep Sharma, Rohit Verma, Gulsheen Ahuja and Manmohan Gupta
Implications of theta_13 on Fritzsch-like lepton mass matrices
18 pages, 8 figures. arXiv admin note: substantial text overlap with arXiv:hep-ph/0607074, arXiv:hep-ph/0703005, arXiv:0904.4534
Physics Letters B 720 (2013) 366
10.1016/j.physletb.2013.02.044
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Implications of the lepton mixing angles, in particular of theta_13, have been investigated for minimal as well as non-minimal Fritzsch-like textures for the case of Majorana neutrinos. Both, in minimal texture (texture 6 zero lepton mass matrices) and non-minimal textures (two cases of texture 5 zero lepton mass matrices), inverted hierarchy and degenerate scenario of neutrino masses have been ruled out. The implications of theta_13 have been investigated on the lightest neutrino mass m_\nu_1 as well as the effective Majorana mass m_ee.
[ { "created": "Fri, 25 Jan 2013 06:48:04 GMT", "version": "v1" } ]
2015-06-12
[ [ "Fakay", "Priyanka", "" ], [ "Sharma", "Samandeep", "" ], [ "Verma", "Rohit", "" ], [ "Ahuja", "Gulsheen", "" ], [ "Gupta", "Manmohan", "" ] ]
Implications of the lepton mixing angles, in particular of theta_13, have been investigated for minimal as well as non-minimal Fritzsch-like textures for the case of Majorana neutrinos. Both, in minimal texture (texture 6 zero lepton mass matrices) and non-minimal textures (two cases of texture 5 zero lepton mass matrices), inverted hierarchy and degenerate scenario of neutrino masses have been ruled out. The implications of theta_13 have been investigated on the lightest neutrino mass m_\nu_1 as well as the effective Majorana mass m_ee.
1912.12839
Priyanka Lamba
Emilian Dudas, Priyanka Lamba, Sudhir K. Vempati
Diluting SUSY flavour problem on the Landscape
18 pages, 8 figures
null
10.1016/j.physletb.2020.135404
CPHT-RR108.122019
hep-ph
http://creativecommons.org/publicdomain/zero/1.0/
We consider an explicit effective field theory example based on the Bousso-Polchinski framework with a large number N of hidden sectors contributing to supersymmetry breaking. Each contribution comes from four form quantized fluxes, multiplied by random couplings. The soft terms in the observable sector in this case become random variables, with mean values and standard deviations which are computable. We show that this setup naturally leads to a solution of the flavor problem in low-energy supersymmetry if N is sufficiently large. We investigate the consequences for flavor violating processes at low-energy and for dark matter.
[ { "created": "Mon, 30 Dec 2019 07:55:37 GMT", "version": "v1" } ]
2020-04-08
[ [ "Dudas", "Emilian", "" ], [ "Lamba", "Priyanka", "" ], [ "Vempati", "Sudhir K.", "" ] ]
We consider an explicit effective field theory example based on the Bousso-Polchinski framework with a large number N of hidden sectors contributing to supersymmetry breaking. Each contribution comes from four form quantized fluxes, multiplied by random couplings. The soft terms in the observable sector in this case become random variables, with mean values and standard deviations which are computable. We show that this setup naturally leads to a solution of the flavor problem in low-energy supersymmetry if N is sufficiently large. We investigate the consequences for flavor violating processes at low-energy and for dark matter.
hep-ph/9511381
Kazuya Kumekawa
H.Fujisaki, K.Kumekawa, M.Yamaguchi, M.Yoshimura
Particle Production and Gravitino Abundance after Inflation
23 pages + 13 figures
Phys.Rev.D54:2494-2503,1996
10.1103/PhysRevD.54.2494
TU/95/493, TUM-HEP-229/95, SFB-375/24
hep-ph astro-ph
null
Thermal history after inflation is studied in a chaotic inflation model with supersymmetric couplings of the inflaton to matter fields. Time evolution equation is solved in a formalism that incorporates both the back reaction of particle production and the cosmological expansion. The effect of the parametric resonance gives rise to a rapid initial phase of the inflaton decay followed by a slow stage of the Born term decay. Thermalization takes place immediately after the first explosive stage for a medium strength of the coupling among created particles. As an application we calculate time evolution of the gravitino abundance that is produced by ordinary particles directly created from the inflaton decay, which typically results in much more enhanced yield than what a naive estimate based on the Born term would suggest.
[ { "created": "Tue, 21 Nov 1995 09:27:33 GMT", "version": "v1" } ]
2014-11-17
[ [ "Fujisaki", "H.", "" ], [ "Kumekawa", "K.", "" ], [ "Yamaguchi", "M.", "" ], [ "Yoshimura", "M.", "" ] ]
Thermal history after inflation is studied in a chaotic inflation model with supersymmetric couplings of the inflaton to matter fields. Time evolution equation is solved in a formalism that incorporates both the back reaction of particle production and the cosmological expansion. The effect of the parametric resonance gives rise to a rapid initial phase of the inflaton decay followed by a slow stage of the Born term decay. Thermalization takes place immediately after the first explosive stage for a medium strength of the coupling among created particles. As an application we calculate time evolution of the gravitino abundance that is produced by ordinary particles directly created from the inflaton decay, which typically results in much more enhanced yield than what a naive estimate based on the Born term would suggest.
1810.05675
Peter Stoffer
Wouter Dekens, Elizabeth E. Jenkins, Aneesh V. Manohar, Peter Stoffer
Non-Perturbative Effects in $\mu \to e \gamma$
21 pages, 1 figure; version published in JHEP
JHEP 1901 (2019) 088
10.1007/JHEP01(2019)088
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the non-perturbative contribution of semileptonic tensor operators $(\bar q \sigma^{\mu \nu} q)(\bar \ell \sigma_{\mu \nu} \ell)$ to the purely leptonic process $\mu \to e \gamma$ and to the electric and magnetic dipole moments of charged leptons by matching onto chiral perturbation theory at low energies. This matching procedure has been used extensively to study semileptonic and leptonic weak decays of hadrons. In this paper, we apply it to observables that contain no strongly interacting external particles. The non-perturbative contribution to $\mu \to e $ processes is used to extract the best current bound on lepton-flavor-violating semileptonic tensor operators, $\Lambda_\text{BSM} \gtrsim 450$ TeV. We briefly discuss how the same method applies to dark-matter interactions.
[ { "created": "Fri, 12 Oct 2018 18:46:16 GMT", "version": "v1" }, { "created": "Thu, 24 Jan 2019 19:50:12 GMT", "version": "v2" } ]
2019-01-28
[ [ "Dekens", "Wouter", "" ], [ "Jenkins", "Elizabeth E.", "" ], [ "Manohar", "Aneesh V.", "" ], [ "Stoffer", "Peter", "" ] ]
We compute the non-perturbative contribution of semileptonic tensor operators $(\bar q \sigma^{\mu \nu} q)(\bar \ell \sigma_{\mu \nu} \ell)$ to the purely leptonic process $\mu \to e \gamma$ and to the electric and magnetic dipole moments of charged leptons by matching onto chiral perturbation theory at low energies. This matching procedure has been used extensively to study semileptonic and leptonic weak decays of hadrons. In this paper, we apply it to observables that contain no strongly interacting external particles. The non-perturbative contribution to $\mu \to e $ processes is used to extract the best current bound on lepton-flavor-violating semileptonic tensor operators, $\Lambda_\text{BSM} \gtrsim 450$ TeV. We briefly discuss how the same method applies to dark-matter interactions.
1707.08067
George Leontaris
Thomas W. Kephart, George K. Leontaris, Qaisar Shafi
Magnetic Monopoles and Free Fractionally Charged States at Accelerators and in Cosmic Rays
18 pages, 2 figures, minor revisions, references added
null
10.1007/JHEP10(2017)176
null
hep-ph hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Unified theories of strong, weak and electromagnetic interactions which have electric charge quantization predict the existence of topologically stable magnetic monopoles. Intermediate scale monopoles are comparable with detection energies of cosmic ray monopoles at IceCube and other cosmic ray experiments. Magnetic monopoles in some models can be significantly lighter and carry two, three or possibly even higher quanta of the Dirac magnetic charge. They could be light enough for their effects to be detected at the LHC either directly or indirectly. An example based on a D-brane inspired $SU(3)_C\times SU(3)_L\times SU(3)_R$ (trinification) model with the monopole carrying three quanta of Dirac magnetic charge is presented. These theories also predict the existence of color singlet states with fractional electric charge which may be accessible at the LHC.
[ { "created": "Tue, 25 Jul 2017 16:16:36 GMT", "version": "v1" }, { "created": "Thu, 28 Sep 2017 00:52:17 GMT", "version": "v2" } ]
2017-12-06
[ [ "Kephart", "Thomas W.", "" ], [ "Leontaris", "George K.", "" ], [ "Shafi", "Qaisar", "" ] ]
Unified theories of strong, weak and electromagnetic interactions which have electric charge quantization predict the existence of topologically stable magnetic monopoles. Intermediate scale monopoles are comparable with detection energies of cosmic ray monopoles at IceCube and other cosmic ray experiments. Magnetic monopoles in some models can be significantly lighter and carry two, three or possibly even higher quanta of the Dirac magnetic charge. They could be light enough for their effects to be detected at the LHC either directly or indirectly. An example based on a D-brane inspired $SU(3)_C\times SU(3)_L\times SU(3)_R$ (trinification) model with the monopole carrying three quanta of Dirac magnetic charge is presented. These theories also predict the existence of color singlet states with fractional electric charge which may be accessible at the LHC.
1308.2679
Anthony DiFranzo
Anthony DiFranzo, Keiko I. Nagao, Arvind Rajaraman, Tim M.P. Tait
Simplified Models for Dark Matter Interacting with Quarks
12 pages, 13 figures (39 images) Fixed erroneous calculation and updated plots
JHEP 1311 (2013) 014
10.1007/JHEP11(2013)014
UCI-HEP-TR-2013-17, KEK-TH 1659
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate simplified models in which dark matter particles, taken to be either Dirac or Majorana fermions, couple to quarks via colored mediators. We determine bounds from colliders and direct detection experiments, and show how the interplay of the two leads to a complementary view of this class of dark matter models. Forecasts for future searches in light of the current constraints are presented.
[ { "created": "Mon, 12 Aug 2013 20:00:11 GMT", "version": "v1" }, { "created": "Mon, 30 Dec 2013 22:23:09 GMT", "version": "v2" } ]
2015-06-16
[ [ "DiFranzo", "Anthony", "" ], [ "Nagao", "Keiko I.", "" ], [ "Rajaraman", "Arvind", "" ], [ "Tait", "Tim M. P.", "" ] ]
We investigate simplified models in which dark matter particles, taken to be either Dirac or Majorana fermions, couple to quarks via colored mediators. We determine bounds from colliders and direct detection experiments, and show how the interplay of the two leads to a complementary view of this class of dark matter models. Forecasts for future searches in light of the current constraints are presented.
hep-ph/0207245
Adam K. Leibovich
Adam K. Leibovich
Radiative Upsilon Decay at the Endpoint
Talk at 5th International Conference on Hyperons, Charm and Beauty Hadrons (BEACH 2002), Vancouver, Canada, 25-29 Jun 2002
Nucl.Phys.Proc.Suppl. 115 (2003) 183-186
10.1016/S0920-5632(02)01987-4
FERMILAB-CONF-02/160-T
hep-ph
null
The standard NRQCD power counting breaks down and the OPE gives rise to color-octet shape functions at the upper endpoint of the photon energy spectrum in radiative Upsilon decay. Also in this kinematic regime, large Sudakov logarithms appear in the octet Wilson coefficients, ruining the perturbative expansion. Using SCET, the octet shape functions arise naturally and the Sudakov logarithms can be summed using the renormalization group equations. We derive an expression for the resummed octet energy spectrum.
[ { "created": "Fri, 19 Jul 2002 19:10:46 GMT", "version": "v1" } ]
2009-11-07
[ [ "Leibovich", "Adam K.", "" ] ]
The standard NRQCD power counting breaks down and the OPE gives rise to color-octet shape functions at the upper endpoint of the photon energy spectrum in radiative Upsilon decay. Also in this kinematic regime, large Sudakov logarithms appear in the octet Wilson coefficients, ruining the perturbative expansion. Using SCET, the octet shape functions arise naturally and the Sudakov logarithms can be summed using the renormalization group equations. We derive an expression for the resummed octet energy spectrum.
2307.08734
Kaapo Sepp\"anen
Tyler Gorda, Risto Paatelainen, Saga S\"appi, Kaapo Sepp\"anen
Equation of State of Cold Quark Matter to $O(\alpha_s^3 \ln \alpha_s)$
Corresponds to the published version. 7 pages (main text), 6 pages (supplemental material), 2 figures, 2 tables
Phys.Rev.Lett. 131, 181902 (2023)
10.1103/PhysRevLett.131.181902
HIP-2023-10/TH, TUM-EFT 181/23
hep-ph astro-ph.HE nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Accurately understanding the equation of state (EOS) of high-density, zero-temperature quark matter plays an essential role in constraining the behavior of dense strongly interacting matter inside the cores of neutron stars. In this Letter, we study the weak-coupling expansion of the EOS of cold quark matter and derive the complete, gauge-invariant contributions from the long-wavelength, dynamically screened gluonic sector at next-to-next-to-next-to-leading order (N3LO) in the strong coupling constant $\alpha_s$. This elevates the EOS result to the $O(\alpha_s^3 \ln \alpha_s)$ level, leaving only one unknown constant from the unscreened sector at N3LO, and places it on par with its high-temperature counterpart from 2003.
[ { "created": "Mon, 17 Jul 2023 18:00:01 GMT", "version": "v1" }, { "created": "Mon, 13 Nov 2023 11:13:32 GMT", "version": "v2" } ]
2023-11-14
[ [ "Gorda", "Tyler", "" ], [ "Paatelainen", "Risto", "" ], [ "Säppi", "Saga", "" ], [ "Seppänen", "Kaapo", "" ] ]
Accurately understanding the equation of state (EOS) of high-density, zero-temperature quark matter plays an essential role in constraining the behavior of dense strongly interacting matter inside the cores of neutron stars. In this Letter, we study the weak-coupling expansion of the EOS of cold quark matter and derive the complete, gauge-invariant contributions from the long-wavelength, dynamically screened gluonic sector at next-to-next-to-next-to-leading order (N3LO) in the strong coupling constant $\alpha_s$. This elevates the EOS result to the $O(\alpha_s^3 \ln \alpha_s)$ level, leaving only one unknown constant from the unscreened sector at N3LO, and places it on par with its high-temperature counterpart from 2003.
1903.11489
Adil Jueid
Abdesslam Arhrib, Adil Jueid, Stefano Moretti
Searching for Heavy Charged Higgs Bosons through Top Quark Polarization
7 pages; 2 Figures; 2 Tables; To appear for IAS Program on HEP, January 2019, Hong Kong, based on arXiv:1807.11306
null
10.1142/S0217751X20410110
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the production of a heavy charged Higgs boson at the Large Hadron Collider (LHC) in $gb\to H^{-} t$ within a Two Higgs Doublet Model (2HDM). The chiral structure of the $H^{-} t \bar{b}$ coupling can trigger a particular spin state of the top quark produced in the decay of a charged Higgs boson and, therefore, is sensitive to the underlying mechanism of the Electro-Weak Symmetry Breaking (EWSB). Taking two benchmark models (2HDM type-I and 2HDM type-Y) as an example, we show that inclusive rates, differential distributions as well as forward-backward asymmetries of the top quark's decay products can be used to search for heavy charged Higgs bosons as well as a model discriminators.
[ { "created": "Wed, 27 Mar 2019 15:29:28 GMT", "version": "v1" } ]
2020-07-15
[ [ "Arhrib", "Abdesslam", "" ], [ "Jueid", "Adil", "" ], [ "Moretti", "Stefano", "" ] ]
We study the production of a heavy charged Higgs boson at the Large Hadron Collider (LHC) in $gb\to H^{-} t$ within a Two Higgs Doublet Model (2HDM). The chiral structure of the $H^{-} t \bar{b}$ coupling can trigger a particular spin state of the top quark produced in the decay of a charged Higgs boson and, therefore, is sensitive to the underlying mechanism of the Electro-Weak Symmetry Breaking (EWSB). Taking two benchmark models (2HDM type-I and 2HDM type-Y) as an example, we show that inclusive rates, differential distributions as well as forward-backward asymmetries of the top quark's decay products can be used to search for heavy charged Higgs bosons as well as a model discriminators.
2204.05197
Egle Tomasi-Gustafsson
Andrea Bianconi, Egle Tomasi-Gustafsson
Compared analysis of time-like hyperon form factors
20 pages, 10 figures
null
10.1103/PhysRevC.105.065206
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Data on hyperon form factors recently obtained from annihilation reactions are compared each other, and to proton and neutron form factors, in terms of two kinematical variables: the transferred momentum square, $q^2$, and the modulus $P$ of the relative momentum between the outgoing baryons. They are critically discussed in terms of possible correlated structures. The present status of the time-like form factor data for baryons is described and suggestions are given on the reactions and the kinematical range where data are desirable in order to clarify the arisen questions.
[ { "created": "Mon, 11 Apr 2022 15:36:23 GMT", "version": "v1" } ]
2022-07-13
[ [ "Bianconi", "Andrea", "" ], [ "Tomasi-Gustafsson", "Egle", "" ] ]
Data on hyperon form factors recently obtained from annihilation reactions are compared each other, and to proton and neutron form factors, in terms of two kinematical variables: the transferred momentum square, $q^2$, and the modulus $P$ of the relative momentum between the outgoing baryons. They are critically discussed in terms of possible correlated structures. The present status of the time-like form factor data for baryons is described and suggestions are given on the reactions and the kinematical range where data are desirable in order to clarify the arisen questions.
2110.12451
Neetu Raj Singh Chundawat
Ashutosh Kumar Alok, Neetu Raj Singh Chundawat, Dinesh Kumar
Impact of $b \to s \ell \ell$ anomalies on rare charm decays in non-universal $Z'$ models
23 pages, 3 figures; Published version
Eur. Phys. J. C 82, 30 (2022)
10.1140/epjc/s10052-021-09975-z
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we study the impact of $b \to s \ell \ell$, $B_s - \bar{B_s}$ mixing and neutrino trident measurements on observables in decays induced by $c \to u $ transition in the context of a non-universal $Z'$ model which generates $C^{\rm NP}_{9} <0$ and $C^{\rm NP}_9 = - \,C^{\rm NP}_{10} $ new physics scenarios at the tree level. We inspect the effects on $D^0 \to \pi^0 \nu \bar{\nu}$, $D^+ \to \pi^+ \nu \bar{\nu}$ and $B_c \to B^+ \nu \bar{\nu} $ decays which are induced by the quark level transition $c \to u \nu \bar{\nu}$. The fact that the branching ratios of these decays are negligible in the standard model (SM) and the long distance effects are relatively smaller in comparison to their charged dileptons counterparts, they are considered to provide genuine null-tests of SM. Therefore the observation of these modes at the level of current as well as planned experimental sensitivities would imply unambiguous signature of new physics. Using the constraints on $Z'$ couplings coming from a combined fit to $b \to s \ell \ell$, $\Delta M_s$ and neutrino trident data, we find that any meaningful enhancement over the SM value is ruled out in the considered framework. The same is true for $D - \bar{D}$ mixing observable $\Delta M_D$ along with $D^0 \to \mu^+ \mu^-$ and $D^+ \to \pi^+ \mu^+ \mu^-$ decay modes which are induced through $c \to u \mu^+ \mu^-$ transition.
[ { "created": "Sun, 24 Oct 2021 14:11:53 GMT", "version": "v1" }, { "created": "Thu, 24 Feb 2022 10:19:56 GMT", "version": "v2" } ]
2022-11-16
[ [ "Alok", "Ashutosh Kumar", "" ], [ "Chundawat", "Neetu Raj Singh", "" ], [ "Kumar", "Dinesh", "" ] ]
In this work, we study the impact of $b \to s \ell \ell$, $B_s - \bar{B_s}$ mixing and neutrino trident measurements on observables in decays induced by $c \to u $ transition in the context of a non-universal $Z'$ model which generates $C^{\rm NP}_{9} <0$ and $C^{\rm NP}_9 = - \,C^{\rm NP}_{10} $ new physics scenarios at the tree level. We inspect the effects on $D^0 \to \pi^0 \nu \bar{\nu}$, $D^+ \to \pi^+ \nu \bar{\nu}$ and $B_c \to B^+ \nu \bar{\nu} $ decays which are induced by the quark level transition $c \to u \nu \bar{\nu}$. The fact that the branching ratios of these decays are negligible in the standard model (SM) and the long distance effects are relatively smaller in comparison to their charged dileptons counterparts, they are considered to provide genuine null-tests of SM. Therefore the observation of these modes at the level of current as well as planned experimental sensitivities would imply unambiguous signature of new physics. Using the constraints on $Z'$ couplings coming from a combined fit to $b \to s \ell \ell$, $\Delta M_s$ and neutrino trident data, we find that any meaningful enhancement over the SM value is ruled out in the considered framework. The same is true for $D - \bar{D}$ mixing observable $\Delta M_D$ along with $D^0 \to \mu^+ \mu^-$ and $D^+ \to \pi^+ \mu^+ \mu^-$ decay modes which are induced through $c \to u \mu^+ \mu^-$ transition.
hep-ph/0307386
Bernd Kniehl
B.A. Kniehl, G. Kramer (Hamburg U.), C.P. Palisoc (Philippines U.)
chi_{c1} and chi_{c2} decay angular distributions at the Fermilab Tevatron
26 pages, 14 figures
Phys.Rev. D68 (2003) 114002
10.1103/PhysRevD.68.114002
DESY 03-096
hep-ph hep-ex
null
We consider the hadroproduction of chi_{c1} and chi_{c2} mesons and their subsequent radiative decays to J/psi mesons and photons in the factorization formalism of nonrelativistic quantum chromodynamics, and study the decay angular distributions, by means of helicity density matrices, in view of their sensitivity to color-octet processes. We present numerical results appropriate for the Fermilab Tevatron.
[ { "created": "Thu, 31 Jul 2003 09:43:15 GMT", "version": "v1" } ]
2009-11-10
[ [ "Kniehl", "B. A.", "", "Hamburg U." ], [ "Kramer", "G.", "", "Hamburg U." ], [ "Palisoc", "C. P.", "", "Philippines U." ] ]
We consider the hadroproduction of chi_{c1} and chi_{c2} mesons and their subsequent radiative decays to J/psi mesons and photons in the factorization formalism of nonrelativistic quantum chromodynamics, and study the decay angular distributions, by means of helicity density matrices, in view of their sensitivity to color-octet processes. We present numerical results appropriate for the Fermilab Tevatron.
hep-ph/0612325
Patricia Ball
Patricia Ball
Constraints on New Physics from gamma and |V_ub|
Talk given at CKM06; one reference added
null
null
IPPP/06/95
hep-ph
null
The SM unitarity triangle (UT) is completely determined by the parameters $\gamma$ and $|V_{ub}|$ which can be extracted from tree-level processes and are assumed to be free of new physics. By comparison with other determinations of UT parameters one can impose constraints on new physics in loop processes, in particular $B$ mixing.
[ { "created": "Sun, 24 Dec 2006 15:46:04 GMT", "version": "v1" }, { "created": "Wed, 31 Jan 2007 14:15:21 GMT", "version": "v2" } ]
2007-05-23
[ [ "Ball", "Patricia", "" ] ]
The SM unitarity triangle (UT) is completely determined by the parameters $\gamma$ and $|V_{ub}|$ which can be extracted from tree-level processes and are assumed to be free of new physics. By comparison with other determinations of UT parameters one can impose constraints on new physics in loop processes, in particular $B$ mixing.
hep-ph/0402034
C. A. de S. Pires
S. M. Lietti and C. A. de S. Pires
Testing Non commutative QED gamma-gamma-gamma and gamma-gamma-gamma-gamma Couplings at LHC
minor changes, references added, version to appears in EPJC
Eur.Phys.J. C35 (2004) 137-143
10.1140/epjc/s2004-01777-5
null
hep-ph
null
In this work, we investigate the sensitivity of the process p + p --> q + q --> j + j + gamma + gamma at LHC for the photonic 3- and 4- point functions that appear in non commutative QED. We show that this process serves to study the behavior of the space-space as well as of the space-time non commutativity. We also show that this process can probe the non commutative scale in the range of few TeV.
[ { "created": "Tue, 3 Feb 2004 18:21:11 GMT", "version": "v1" }, { "created": "Wed, 28 Apr 2004 11:40:10 GMT", "version": "v2" } ]
2009-11-10
[ [ "Lietti", "S. M.", "" ], [ "Pires", "C. A. de S.", "" ] ]
In this work, we investigate the sensitivity of the process p + p --> q + q --> j + j + gamma + gamma at LHC for the photonic 3- and 4- point functions that appear in non commutative QED. We show that this process serves to study the behavior of the space-space as well as of the space-time non commutativity. We also show that this process can probe the non commutative scale in the range of few TeV.
1403.3778
Renata Jora
Renata Jora, Joseph Schechter
A hint of a strong supersymmetric standard model
6 pages, 2 figures
null
10.1142/S0217751X14501929
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the supersymmetric standard model from the perspective that the up and down Higgs supermultiplets are composite states. We show that a Higgs multiplet in which the scalar states are bound states of two squarks and the corresponding Higgsinos are bound states of a quark and an squark has the correct supersymmetry transformations and may lead to an alternative model which displays dynamical symmetry breaking. We describe this model through an effective Higgs potential which by itself may lead to the correct mass of 125.9 GeV for the lightest Higgs boson and to other neutral scalar masses respecting the experimental constraints.
[ { "created": "Sat, 15 Mar 2014 10:05:23 GMT", "version": "v1" } ]
2015-06-19
[ [ "Jora", "Renata", "" ], [ "Schechter", "Joseph", "" ] ]
We discuss the supersymmetric standard model from the perspective that the up and down Higgs supermultiplets are composite states. We show that a Higgs multiplet in which the scalar states are bound states of two squarks and the corresponding Higgsinos are bound states of a quark and an squark has the correct supersymmetry transformations and may lead to an alternative model which displays dynamical symmetry breaking. We describe this model through an effective Higgs potential which by itself may lead to the correct mass of 125.9 GeV for the lightest Higgs boson and to other neutral scalar masses respecting the experimental constraints.
hep-ph/0210309
Yu. A. Simonov
Yu.A. Simonov (ITEP, Moscow)
Spectrum and Regge-trajectories in QCD
15 pages, 1 eps figure, Latex2e, Invited Talk at the International Seminar devoted to 80-th birthday of K.A. Ter-Martirosyan, to be published in Proceedings
Phys.Atom.Nucl. 66 (2003) 2038-2044; Yad.Fiz. 66 (2003) 2088-2094
10.1134/1.1625746
null
hep-ph
null
Starting in sixties an active group of physicists under the guidance of Prof. K.A.Ter-Martirosyan was creating the theory of high-energy processes in QCD. From the beginning the key element of this theory is the notion of Regge trajectories and in particular of the pomeron trajectory, which have been introduced phenomenologically. In this talk I review the problem of spectrum and Regge trajectories as it can be derived from the nonperturbative QCD dynamics.
[ { "created": "Wed, 23 Oct 2002 10:45:24 GMT", "version": "v1" } ]
2009-11-07
[ [ "Simonov", "Yu. A.", "", "ITEP, Moscow" ] ]
Starting in sixties an active group of physicists under the guidance of Prof. K.A.Ter-Martirosyan was creating the theory of high-energy processes in QCD. From the beginning the key element of this theory is the notion of Regge trajectories and in particular of the pomeron trajectory, which have been introduced phenomenologically. In this talk I review the problem of spectrum and Regge trajectories as it can be derived from the nonperturbative QCD dynamics.
1109.2562
Stephen Barr
S.M. Barr
The Unification and Cogeneration of Dark Matter and Baryonic Matter
17 pages, 2 figures, corrected typos and added references
null
10.1103/PhysRevD.85.013001
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In grand unified theories with gauge groups larger than SU(5), the multiplets that contain the known quarks and leptons also contain fermions that are singlets under the Standard Model gauge group. Some of these could be the dark matter of the universe. Grand unified theories can also have accidental U(1) global symmetries (analogous to B-L in minimal SU(5)) that can stabilize dark matter. These ideas are illustrated in an SU(6) model.
[ { "created": "Mon, 12 Sep 2011 18:38:53 GMT", "version": "v1" }, { "created": "Sun, 18 Sep 2011 13:18:41 GMT", "version": "v2" } ]
2013-05-30
[ [ "Barr", "S. M.", "" ] ]
In grand unified theories with gauge groups larger than SU(5), the multiplets that contain the known quarks and leptons also contain fermions that are singlets under the Standard Model gauge group. Some of these could be the dark matter of the universe. Grand unified theories can also have accidental U(1) global symmetries (analogous to B-L in minimal SU(5)) that can stabilize dark matter. These ideas are illustrated in an SU(6) model.
1109.3231
Nikolaos Kidonakis
Nikolaos Kidonakis
Top Quark Theoretical Cross Sections and pT and Rapidity Distributions
8 pages, 10 figures; Proceedings of the DPF-2011 Conference, Providence, RI, August 8-13, 2011
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I present theoretical results for the top quark pair total cross section, and for the top quark transverse momentum and rapidity distributions at Tevatron and LHC energies. I also present results for single top quark production in the t- and s-channels and also via associated production with a W boson. The calculations include approximate NNLO corrections that are derived from NNLL soft-gluon resummation.
[ { "created": "Thu, 15 Sep 2011 00:15:51 GMT", "version": "v1" } ]
2011-09-16
[ [ "Kidonakis", "Nikolaos", "" ] ]
I present theoretical results for the top quark pair total cross section, and for the top quark transverse momentum and rapidity distributions at Tevatron and LHC energies. I also present results for single top quark production in the t- and s-channels and also via associated production with a W boson. The calculations include approximate NNLO corrections that are derived from NNLL soft-gluon resummation.
hep-ph/0304074
Stuart Raby
Stuart Raby
Phenomenology of the Minimal SO(10) SUSY Model
14 pages, Invited talk at PASCOS'03, Mumbai, India, January 3 - 8, 2003, corrected equation in section 5.2
Pramana62:523-536,2004
10.1007/BF02705106
OHSTPY-HEP-T-03-005
hep-ph
null
In this talk I define what I call the minimal SO(10) SUSY model. I then discuss the phenomenological consequences of this theory, vis a vis gauge and Yukawa coupling unification, Higgs and super-particle masses, the anomalous magnetic moment of the muon, the decay $B_s \to \mu^+ \mu^-$ and dark matter.
[ { "created": "Mon, 7 Apr 2003 21:10:43 GMT", "version": "v1" }, { "created": "Thu, 10 Apr 2003 13:14:39 GMT", "version": "v2" }, { "created": "Sat, 11 Oct 2003 15:17:51 GMT", "version": "v3" } ]
2008-11-26
[ [ "Raby", "Stuart", "" ] ]
In this talk I define what I call the minimal SO(10) SUSY model. I then discuss the phenomenological consequences of this theory, vis a vis gauge and Yukawa coupling unification, Higgs and super-particle masses, the anomalous magnetic moment of the muon, the decay $B_s \to \mu^+ \mu^-$ and dark matter.
0706.4244
Marco Roncadelli
Marco Roncadelli
Behind Pvlas
Talk given at the ``XII International Workshop on Neutrino Telescopes'' (to appear in the Proceedings)
null
null
null
hep-ph
null
We offer a detailed review of the physics behind the PVLAS experiment. We also address some laboratory and astrophysical cross-checks for the recent claim concerning a signal consistent with an Axion-Like Particle. Our aim is that the leading role played by Emilio (Mimmo) Zavattini in this field of research will become apparent.
[ { "created": "Thu, 28 Jun 2007 14:19:29 GMT", "version": "v1" } ]
2007-06-29
[ [ "Roncadelli", "Marco", "" ] ]
We offer a detailed review of the physics behind the PVLAS experiment. We also address some laboratory and astrophysical cross-checks for the recent claim concerning a signal consistent with an Axion-Like Particle. Our aim is that the leading role played by Emilio (Mimmo) Zavattini in this field of research will become apparent.
hep-ph/0501097
Gavin Salam
G.P. Salam
Asymptotics and preasymptotics at small x
7 pages. Talk presented at the QCD at cosmic energies workshop, Ettore Majorana Centre, Erice, Italy, September 2004
null
null
LPTHE-P05-02
hep-ph
null
This talk discusses the relative impact of running-coupling and other higher-order corrections on the small-x gluon-gluon splitting function. Comments are made on similarities with some aspects of the Balitsky-Kovchegov equation, which arise because of the presence of an effective infrared cutoff in both cases. It is emphasised that, at least in the splitting-function case, the asymptotic small-x behaviour has little relevance to the phenomenologically interesting preasymptotic region. This is illustrated with the aid of a convolution of the resummed splitting function with a toy gluon distribution.
[ { "created": "Wed, 12 Jan 2005 15:25:06 GMT", "version": "v1" } ]
2007-05-23
[ [ "Salam", "G. P.", "" ] ]
This talk discusses the relative impact of running-coupling and other higher-order corrections on the small-x gluon-gluon splitting function. Comments are made on similarities with some aspects of the Balitsky-Kovchegov equation, which arise because of the presence of an effective infrared cutoff in both cases. It is emphasised that, at least in the splitting-function case, the asymptotic small-x behaviour has little relevance to the phenomenologically interesting preasymptotic region. This is illustrated with the aid of a convolution of the resummed splitting function with a toy gluon distribution.
hep-ph/0302271
C. A. Dominguez
H. Castillo, C.A. Dominguez, M. Loewe
Electromagnetic nucleon form factors from QCD sum rules
Replaced Version. An error has been corrected in the numerical evaluation of the Pauli form factor. This changes the results for F_2(q^2), as well as the conclusions
JHEP 0503 (2005) 012
10.1088/1126-6708/2005/03/012
UCT-TP-260/03
hep-ph
null
The electromagnetic form factors of the nucleon, in the space-like region, are determined from three-point function Finite Energy QCD Sum Rules. The QCD calculation is performed to leading order in perturbation theory in the chiral limit, and to leading order in the non-perturbative power corrections. The results for the Dirac form factor, $F_1(q^2)$, are in very good agreement with data for both the proton and the neutron, in the currently accessible experimental region of momentum transfers. This is not the case, though, for the Pauli form factor $F_2(q^2)$, which has a soft $q^2$-dependence proportional to the quark condensate $<0|\bar{q}q|0>$.
[ { "created": "Fri, 28 Feb 2003 09:49:26 GMT", "version": "v1" }, { "created": "Fri, 21 Jan 2005 17:56:36 GMT", "version": "v2" } ]
2009-11-10
[ [ "Castillo", "H.", "" ], [ "Dominguez", "C. A.", "" ], [ "Loewe", "M.", "" ] ]
The electromagnetic form factors of the nucleon, in the space-like region, are determined from three-point function Finite Energy QCD Sum Rules. The QCD calculation is performed to leading order in perturbation theory in the chiral limit, and to leading order in the non-perturbative power corrections. The results for the Dirac form factor, $F_1(q^2)$, are in very good agreement with data for both the proton and the neutron, in the currently accessible experimental region of momentum transfers. This is not the case, though, for the Pauli form factor $F_2(q^2)$, which has a soft $q^2$-dependence proportional to the quark condensate $<0|\bar{q}q|0>$.
1906.06364
Divya Sachdeva
Debajyoti Choudhury and Divya Sachdeva
Model Independent analysis of MeV scale dark matter: II. Implications from $e^-e^+$ colliders and Direct Detection
33 pages, 8 figures
Phys. Rev. D 100, 075007 (2019)
10.1103/PhysRevD.100.075007
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dark matter particles with masses in the sub-GeV range have escaped severe constraints from direct detection experiments such as LUX, PANDAX-II and XENON100 as the corresponding recoil energies are, largely, lower than the detector thresholds. In a companion paper, we demonstrated, in a model independent approach, that a significantly large fraction of the parameter space escapes the cosmological and astrophysical constraints. We show here, though, that the remaining parameter space lends itself to the possibility of discovery at both direct detection experiments (such as CRESST-II) as well as in a low-energy collider such as Belle-II.
[ { "created": "Fri, 14 Jun 2019 18:42:52 GMT", "version": "v1" } ]
2019-10-16
[ [ "Choudhury", "Debajyoti", "" ], [ "Sachdeva", "Divya", "" ] ]
Dark matter particles with masses in the sub-GeV range have escaped severe constraints from direct detection experiments such as LUX, PANDAX-II and XENON100 as the corresponding recoil energies are, largely, lower than the detector thresholds. In a companion paper, we demonstrated, in a model independent approach, that a significantly large fraction of the parameter space escapes the cosmological and astrophysical constraints. We show here, though, that the remaining parameter space lends itself to the possibility of discovery at both direct detection experiments (such as CRESST-II) as well as in a low-energy collider such as Belle-II.
2401.01820
Roger Balsach
Roger Balsach, Domenico Bonocore and Anna Kulesza
The emission of soft-photons and the LBK theorem, revisited
7 pages, 4 figures, MTTD23 proceedings
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Predictions for processes involving soft photons, up to next-to-leading power (NLP) in the photon energy, can be obtained using the Low-Burnett-Kroll (LBK) theorem. The consistency of the theorem has been a recent topic of investigation since it is traditionally formulated in terms of a non-radiative amplitude, which is evaluated with unphysical momenta. We address such questions and propose a formulation of the LBK theorem which relies on the evaluation of the non-radiative amplitude with on-shell, physical momenta. We use this form to numerically study the impact of NLP contributions to cross-sections for $pp$ and $e^-e^+$ processes involving soft-photon emission.
[ { "created": "Wed, 3 Jan 2024 16:26:06 GMT", "version": "v1" } ]
2024-01-04
[ [ "Balsach", "Roger", "" ], [ "Bonocore", "Domenico", "" ], [ "Kulesza", "Anna", "" ] ]
Predictions for processes involving soft photons, up to next-to-leading power (NLP) in the photon energy, can be obtained using the Low-Burnett-Kroll (LBK) theorem. The consistency of the theorem has been a recent topic of investigation since it is traditionally formulated in terms of a non-radiative amplitude, which is evaluated with unphysical momenta. We address such questions and propose a formulation of the LBK theorem which relies on the evaluation of the non-radiative amplitude with on-shell, physical momenta. We use this form to numerically study the impact of NLP contributions to cross-sections for $pp$ and $e^-e^+$ processes involving soft-photon emission.
2203.13579
Marco Zaccheddu
Marco Zaccheddu, Umberto D'Alesio, Leonard Gamberg and Francesco Murgia
Extracting the $\Lambda$ Polarizing Fragmentation Function from Belle $e^+e^-$ Data Within the TMD Formalism
6 pages, 2 figures (5 plots), presented by M. Zaccheddu at the 24th International Spin Symposium (SPIN2021), 18-22 October 2021, Matsue, Japan
null
10.7566/JPSCP.37.020111
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Data from the Belle Collaboration for associated production (with a light unpolarized hadron) and single-inclusive production of transversely polarized $\Lambda$-hyperons in $e^+e^-$ annihilation processes allowed to extract within a TMD approach, for the first time, the $\Lambda$ polarizing fragmentation function. Recent theoretical developments on the computation of cross sections for single-inclusive hadron production in $e^+e^-$ annihilation processes, within a Soft Collinear Effective Theory approach, combined with the CSS formalism for the double-hadron production case, can be used to perform a renewed analysis, adopting a full TMD factorization scheme. Preliminary results and a comparison between the two analyses are presented.
[ { "created": "Fri, 25 Mar 2022 11:14:09 GMT", "version": "v1" } ]
2023-01-18
[ [ "Zaccheddu", "Marco", "" ], [ "D'Alesio", "Umberto", "" ], [ "Gamberg", "Leonard", "" ], [ "Murgia", "Francesco", "" ] ]
Data from the Belle Collaboration for associated production (with a light unpolarized hadron) and single-inclusive production of transversely polarized $\Lambda$-hyperons in $e^+e^-$ annihilation processes allowed to extract within a TMD approach, for the first time, the $\Lambda$ polarizing fragmentation function. Recent theoretical developments on the computation of cross sections for single-inclusive hadron production in $e^+e^-$ annihilation processes, within a Soft Collinear Effective Theory approach, combined with the CSS formalism for the double-hadron production case, can be used to perform a renewed analysis, adopting a full TMD factorization scheme. Preliminary results and a comparison between the two analyses are presented.
1302.3909
Diego Guadagnoli
Diego Guadagnoli, Gino Isidori
BR(Bs to mu+ mu-) as an electroweak precision test
8 pages, 1 figure. v3: minor textual modifications; minor update in the numerics; no change in results. Matches journal version (PLB)
Phys.Lett.B724:63-67,2013
10.1016/j.physletb.2013.05.054
LAPTH-010/13, CERN-PH-TH/2013-028
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using an effective-theory approach, we analyze the impact of BR(Bs to mu+ mu-) in constraining new-physics models that predict modifications of the Z-boson couplings to down-type quarks. Under motivated assumptions about the flavor structure of the effective theory, we show that the bounds presently derived from BR(Bs to mu+ mu-) on the effective Z-boson couplings are comparable (in the case of minimal flavor violation) or significantly more stringent (in the case of generic partial compositeness) with respect to those derived from observables at the Z peak.
[ { "created": "Fri, 15 Feb 2013 22:38:51 GMT", "version": "v1" }, { "created": "Mon, 4 Mar 2013 12:53:56 GMT", "version": "v2" }, { "created": "Tue, 11 Jun 2013 07:55:29 GMT", "version": "v3" } ]
2013-12-05
[ [ "Guadagnoli", "Diego", "" ], [ "Isidori", "Gino", "" ] ]
Using an effective-theory approach, we analyze the impact of BR(Bs to mu+ mu-) in constraining new-physics models that predict modifications of the Z-boson couplings to down-type quarks. Under motivated assumptions about the flavor structure of the effective theory, we show that the bounds presently derived from BR(Bs to mu+ mu-) on the effective Z-boson couplings are comparable (in the case of minimal flavor violation) or significantly more stringent (in the case of generic partial compositeness) with respect to those derived from observables at the Z peak.
hep-ph/0605107
Amitabha Lahiri
Chandrasekhar Chatterjee and Amitabha Lahiri
Monopole confinement by flux tube
7pp; brief additions relating monopole strength to winding number, and discussion on length of stable flux tube; one reference added
Europhys.Lett.76:1068-1073,2006
10.1209/epl/i2006-10378-y
null
hep-ph hep-lat hep-th
null
We revisit Nambu's model of quark confinement by a tube of magnetic flux, with two additional features. The quarks are taken to be magnetic monopoles external to the tube, which seal the ends, and are also taken to be fermions. This ensures that the model is inconsistent unless there are at least two species of fermions being confined.
[ { "created": "Wed, 10 May 2006 07:20:03 GMT", "version": "v1" }, { "created": "Tue, 24 Oct 2006 09:26:04 GMT", "version": "v2" } ]
2010-12-17
[ [ "Chatterjee", "Chandrasekhar", "" ], [ "Lahiri", "Amitabha", "" ] ]
We revisit Nambu's model of quark confinement by a tube of magnetic flux, with two additional features. The quarks are taken to be magnetic monopoles external to the tube, which seal the ends, and are also taken to be fermions. This ensures that the model is inconsistent unless there are at least two species of fermions being confined.
1907.01665
Alexander I Nesterov
Alexander I Nesterov, Gennady P Berman, Vladimir Tsifrinovich, Xidi Wang and Marco Merkli
Dark Matter Spin-Spin Interaction through the Pseudo-Scalar Vacuum Field
Typos corrected, accepted version
null
10.1142/S0217732320501175
LA-UR-19-26221
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We suggest that the pseudo-scalar vacuum field (PSV) in the dark matter (DM) sector of the Universe may be as important as the electromagnetic vacuum field in the baryonic sector. In particular, the spin-spin interaction between the DM fermions, mediated by PSV, may represent the strongest interaction between the DM fermions due to the absence of the electric charge and the magnetic dipole moment. Based on this assumption, we consider the influence of the spin-spin interaction, mediated by PSV, on the spin precession of the DM fermions (e. g. neutralino). In the secular approximation, we obtain the exact expression describing the frequency of the precession and estimate the decoherence rate.
[ { "created": "Tue, 2 Jul 2019 22:20:06 GMT", "version": "v1" }, { "created": "Tue, 18 Feb 2020 15:39:20 GMT", "version": "v2" } ]
2020-06-24
[ [ "Nesterov", "Alexander I", "" ], [ "Berman", "Gennady P", "" ], [ "Tsifrinovich", "Vladimir", "" ], [ "Wang", "Xidi", "" ], [ "Merkli", "Marco", "" ] ]
We suggest that the pseudo-scalar vacuum field (PSV) in the dark matter (DM) sector of the Universe may be as important as the electromagnetic vacuum field in the baryonic sector. In particular, the spin-spin interaction between the DM fermions, mediated by PSV, may represent the strongest interaction between the DM fermions due to the absence of the electric charge and the magnetic dipole moment. Based on this assumption, we consider the influence of the spin-spin interaction, mediated by PSV, on the spin precession of the DM fermions (e. g. neutralino). In the secular approximation, we obtain the exact expression describing the frequency of the precession and estimate the decoherence rate.
hep-ph/0102106
Marieke Postma
Marieke Postma
Neutrinos as a signature of ultrahigh energy photons at high red shift
8 pages, 5 figures
Phys.Rev. D64 (2001) 023001
10.1103/PhysRevD.64.023001
UCLA/01/TEP/2
hep-ph astro-ph
null
Sources of ultrahigh energy photons operating at high red shift produce a diffuse background of neutrinos. At high red shift, when the cosmic microwave background radiation has a higher temperature, an electromagnetic cascade originated by an energetic photon can generate neutrinos via muon and pion production and decay. We have calculated numerically the neutrino spectrum produced by various photon sources. A distinctive feature of the produced flux is a ``bump'' in the spectrum at neutrino energies $E \sim 10^{17}$eV. The produced flux is largest for $m=3$ sources ({\it e.g} necklaces), with $E^2 J(E) \sim 10 {\rm eV} {\rm cm}^{-2} {\rm s}^{-1} {\rm sr}^{-1}$ at these energies. Detection of such neutrinos can help understand the origin of ultrahigh energy cosmic rays.
[ { "created": "Thu, 8 Feb 2001 20:16:17 GMT", "version": "v1" } ]
2009-11-07
[ [ "Postma", "Marieke", "" ] ]
Sources of ultrahigh energy photons operating at high red shift produce a diffuse background of neutrinos. At high red shift, when the cosmic microwave background radiation has a higher temperature, an electromagnetic cascade originated by an energetic photon can generate neutrinos via muon and pion production and decay. We have calculated numerically the neutrino spectrum produced by various photon sources. A distinctive feature of the produced flux is a ``bump'' in the spectrum at neutrino energies $E \sim 10^{17}$eV. The produced flux is largest for $m=3$ sources ({\it e.g} necklaces), with $E^2 J(E) \sim 10 {\rm eV} {\rm cm}^{-2} {\rm s}^{-1} {\rm sr}^{-1}$ at these energies. Detection of such neutrinos can help understand the origin of ultrahigh energy cosmic rays.
2404.18993
Luca Di Luzio
Carlo Broggini, Giuseppe Di Carlo, Luca Di Luzio, Claudio Toni
Alpha radioactivity deep-underground as a probe of axion dark matter
7 pages, 3 figures. Added an Appendix providing an analytical treatment of the theta dependence of alpha decay. Version to appear in Physics Letters B
null
null
null
hep-ph hep-ex nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
We propose to investigate the time modulation of radioisotope decays deep underground as a method to explore axion dark matter. In this work, we focus on the $\alpha$-decay of heavy isotopes and develop a theoretical description for the $\theta$-dependence of $\alpha$-decay half-lives, which enables us to predict the time variation of $\alpha$-radioactivity in response to an oscillating axion dark matter background. To probe this scenario, we have recently constructed and installed a setup deep underground at the Gran Sasso Laboratory, based on the $\alpha$-decay of Americium-241. This prototype experiment, named RadioAxion-$\alpha$, will allow us to explore a broad range of oscillation's periods, from a micro-second up to one year, thus providing competitive limits on the axion decay constant across 13 orders of magnitude in the axion mass, ranging from $10^{-9}$ eV to $10^{-20}$ eV after one month of data collection, and down to $10^{-22}$ eV after three years.
[ { "created": "Mon, 29 Apr 2024 18:00:00 GMT", "version": "v1" }, { "created": "Tue, 25 Jun 2024 10:07:12 GMT", "version": "v2" } ]
2024-06-26
[ [ "Broggini", "Carlo", "" ], [ "Di Carlo", "Giuseppe", "" ], [ "Di Luzio", "Luca", "" ], [ "Toni", "Claudio", "" ] ]
We propose to investigate the time modulation of radioisotope decays deep underground as a method to explore axion dark matter. In this work, we focus on the $\alpha$-decay of heavy isotopes and develop a theoretical description for the $\theta$-dependence of $\alpha$-decay half-lives, which enables us to predict the time variation of $\alpha$-radioactivity in response to an oscillating axion dark matter background. To probe this scenario, we have recently constructed and installed a setup deep underground at the Gran Sasso Laboratory, based on the $\alpha$-decay of Americium-241. This prototype experiment, named RadioAxion-$\alpha$, will allow us to explore a broad range of oscillation's periods, from a micro-second up to one year, thus providing competitive limits on the axion decay constant across 13 orders of magnitude in the axion mass, ranging from $10^{-9}$ eV to $10^{-20}$ eV after one month of data collection, and down to $10^{-22}$ eV after three years.
2212.09757
Michael Landry
Michael J. Landry and Hong Liu
A systematic formulation of chiral anomalous magnetohydrodynamics
v2 clarifies the nature of the chrial wave in the linearized perturbations, added references, 24 pages
null
null
MIT-CTP/5509
hep-ph astro-ph.HE cond-mat.mes-hall hep-th nucl-th
http://creativecommons.org/licenses/by/4.0/
We present a new way of deriving effective theories of dynamical electromagnetic fields in general media. It can be used to give a systematic formulation of magnetohydrodynamics (MHD) with strong magnetic fields, including systems with chiral matter and Adler-Bell-Jackiw (ABJ) anomaly. We work in the regime in which velocity and temperature fluctuations can be neglected. The resulting chiral anomalous MHD incorporates and generalizes the chiral magnetic effect, the chiral separation effect, the chiral electric separation effect, as well as recently derived strong-field MHD, all in a single coherent framework. At linearized level, the theory predicts that the chiral magnetic wave does not survive dynamical electromagnetic fields. A different chiral wave, to which we refer as the chiral magnetic electric separation wave, emerges as a result of dynamical versions of the chiral electric separation effect and the chiral magnetic effect. We predict its wave velocity. We also introduce a simple, but solvable nonlinear model to explore the fate of the chiral instability.
[ { "created": "Mon, 19 Dec 2022 19:00:00 GMT", "version": "v1" }, { "created": "Mon, 9 Jan 2023 15:50:00 GMT", "version": "v2" } ]
2023-01-10
[ [ "Landry", "Michael J.", "" ], [ "Liu", "Hong", "" ] ]
We present a new way of deriving effective theories of dynamical electromagnetic fields in general media. It can be used to give a systematic formulation of magnetohydrodynamics (MHD) with strong magnetic fields, including systems with chiral matter and Adler-Bell-Jackiw (ABJ) anomaly. We work in the regime in which velocity and temperature fluctuations can be neglected. The resulting chiral anomalous MHD incorporates and generalizes the chiral magnetic effect, the chiral separation effect, the chiral electric separation effect, as well as recently derived strong-field MHD, all in a single coherent framework. At linearized level, the theory predicts that the chiral magnetic wave does not survive dynamical electromagnetic fields. A different chiral wave, to which we refer as the chiral magnetic electric separation wave, emerges as a result of dynamical versions of the chiral electric separation effect and the chiral magnetic effect. We predict its wave velocity. We also introduce a simple, but solvable nonlinear model to explore the fate of the chiral instability.
1608.03894
Wan-Zhe Feng
Alejandro Celis, Wan-Zhe Feng, Martin Vollmann
Dirac dark matter and $b \to s \ell^+ \ell^-$ with $\mathrm{U(1)}$ gauge symmetry
12 pages, 2 figures
Phys. Rev. D 95, 035018 (2017)
10.1103/PhysRevD.95.035018
LMU-ASC 39/16, TUM-HEP-1069/16
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the possibility of a Dirac fermion dark matter candidate in the light of current $b \to s \ell^+ \ell^-$ anomalies by investigating a minimal extension of the Standard Model with a horizontal $\mathrm{U(1)}^{\prime}$ local symmetry. Dark matter stability is protected by a remnant $\mathcal{Z}_2$ symmetry arising after spontaneous symmetry breaking of $\mathrm{U(1)}^{\prime}$. The associated $Z^{\prime}$ gauge boson can accommodate current hints of new physics in $b \to s \ell^+ \ell^-$ decays, and acts as a vector portal between dark matter and the visible sector. We find that the model is severely constrained by a combination of precision measurements at flavour factories, LHC searches for dilepton resonances, as well as direct and indirect dark matter searches. Despite this, viable regions of the parameter space accommodating the observed dark matter relic abundance and the $b \to s \ell^+ \ell^-$ anomalies still persist for dark matter and $Z^{\prime}$ masses in the TeV range.
[ { "created": "Fri, 12 Aug 2016 20:00:01 GMT", "version": "v1" }, { "created": "Thu, 23 Feb 2017 20:45:46 GMT", "version": "v2" } ]
2017-02-27
[ [ "Celis", "Alejandro", "" ], [ "Feng", "Wan-Zhe", "" ], [ "Vollmann", "Martin", "" ] ]
We revisit the possibility of a Dirac fermion dark matter candidate in the light of current $b \to s \ell^+ \ell^-$ anomalies by investigating a minimal extension of the Standard Model with a horizontal $\mathrm{U(1)}^{\prime}$ local symmetry. Dark matter stability is protected by a remnant $\mathcal{Z}_2$ symmetry arising after spontaneous symmetry breaking of $\mathrm{U(1)}^{\prime}$. The associated $Z^{\prime}$ gauge boson can accommodate current hints of new physics in $b \to s \ell^+ \ell^-$ decays, and acts as a vector portal between dark matter and the visible sector. We find that the model is severely constrained by a combination of precision measurements at flavour factories, LHC searches for dilepton resonances, as well as direct and indirect dark matter searches. Despite this, viable regions of the parameter space accommodating the observed dark matter relic abundance and the $b \to s \ell^+ \ell^-$ anomalies still persist for dark matter and $Z^{\prime}$ masses in the TeV range.
1403.2271
Leonard S. Kisslinger
Leonard S. Kisslinger and Debasish Das
$\Psi$ and $\Upsilon$ Production In pp Collisions at 8.0 TeV
5 pages, 2 figures
Mod. Phys. Lett. A, Vol. 29, No. 16 (2014) 1450082
10.1142/S0217732314500825
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This is an extension of recent studies for $\Upsilon(nS), n=1,2,3,$ and $J/\Psi(1S),\Psi(2S)$ production at the LHC in pp collisions, and with the ALICE detector at 7.0 TeV, with new predictions at 8.0 TeV
[ { "created": "Mon, 10 Mar 2014 15:43:30 GMT", "version": "v1" }, { "created": "Wed, 28 May 2014 19:12:18 GMT", "version": "v2" } ]
2014-05-29
[ [ "Kisslinger", "Leonard S.", "" ], [ "Das", "Debasish", "" ] ]
This is an extension of recent studies for $\Upsilon(nS), n=1,2,3,$ and $J/\Psi(1S),\Psi(2S)$ production at the LHC in pp collisions, and with the ALICE detector at 7.0 TeV, with new predictions at 8.0 TeV
hep-ph/9905268
Youngman Kim
Youngman Kim and Hyun Kyu Lee (Univ. of Hanyang)
Renormalization Group Analysis of \rho-Meson Properties at Finite Density
24 pages, 10 figures, revised version
Phys.Rev. C62 (2000) 037901
10.1103/PhysRevC.62.037901
null
hep-ph
null
We calculate the density dependence of the $\rho$-meson mass and coupling constant($g_{\rho NN}$) for $\rho$-nucleon-nucleon vertex at one loop using the lagrangian where the $\rho$-meson is included as a dynamical gauge boson of a hidden local symmetry. From the condition that thermodynamic potential should not depend on the arbitrary energy scale, renormalization scale, one can construct a renormalization group equation for the thermodynamic potential and argue that the various renormalization group coefficients are functions of the density or temperature. We calculate the $\beta$-function for $\rho$-nucleon-nucleon coupling constant ($g_{\rho NN}$) and $\gamma$-function for $\rho$-meson mass ($\gamma_{m_\rho}$). We found that the $\rho$-meson mass and the coupling constant for $g_{\rho NN}$ drop as density increases in the low energy limit.
[ { "created": "Fri, 7 May 1999 05:30:10 GMT", "version": "v1" }, { "created": "Mon, 9 Aug 1999 05:40:19 GMT", "version": "v2" }, { "created": "Thu, 25 Nov 1999 17:31:21 GMT", "version": "v3" } ]
2016-09-06
[ [ "Kim", "Youngman", "", "Univ. of Hanyang" ], [ "Lee", "Hyun Kyu", "", "Univ. of Hanyang" ] ]
We calculate the density dependence of the $\rho$-meson mass and coupling constant($g_{\rho NN}$) for $\rho$-nucleon-nucleon vertex at one loop using the lagrangian where the $\rho$-meson is included as a dynamical gauge boson of a hidden local symmetry. From the condition that thermodynamic potential should not depend on the arbitrary energy scale, renormalization scale, one can construct a renormalization group equation for the thermodynamic potential and argue that the various renormalization group coefficients are functions of the density or temperature. We calculate the $\beta$-function for $\rho$-nucleon-nucleon coupling constant ($g_{\rho NN}$) and $\gamma$-function for $\rho$-meson mass ($\gamma_{m_\rho}$). We found that the $\rho$-meson mass and the coupling constant for $g_{\rho NN}$ drop as density increases in the low energy limit.
0712.2903
Vyacheslav Rychkov
Riccardo Barbieri, Lawrence J. Hall, Anastasios Y. Papaioannou, Duccio Pappadopulo, Vyacheslav S. Rychkov
An alternative NMSSM phenomenology with manifest perturbative unification
19 pages, 13 figures; v2: possibility of pseudo-Goldstone below 2m_b threshold added, version published by JHEP
JHEP0803:005,2008
10.1088/1126-6708/2008/03/005
UCB-PTH-06/04
hep-ph
null
Can supersymmetric models with a moderate stop mass be made consistent with the negative Higgs boson searches at LEP, while keeping perturbative unification manifest? The NMSSM achieves this rather easily, but only if extra matter multiplets filling complete SU(5) representations are present at intermediate energies. As a concrete example which makes use of this feature, we give an analytic description of the phenomenology of a constrained NMSSM close to a Peccei-Quinn symmetry point. The related pseudo-Goldstone boson appears in decays of the Higgs bosons and possibly of the lightest neutralino, and itself decays into (b anti-b) and (tau anti-tau).
[ { "created": "Tue, 18 Dec 2007 09:29:52 GMT", "version": "v1" }, { "created": "Thu, 6 Mar 2008 12:26:24 GMT", "version": "v2" } ]
2008-11-26
[ [ "Barbieri", "Riccardo", "" ], [ "Hall", "Lawrence J.", "" ], [ "Papaioannou", "Anastasios Y.", "" ], [ "Pappadopulo", "Duccio", "" ], [ "Rychkov", "Vyacheslav S.", "" ] ]
Can supersymmetric models with a moderate stop mass be made consistent with the negative Higgs boson searches at LEP, while keeping perturbative unification manifest? The NMSSM achieves this rather easily, but only if extra matter multiplets filling complete SU(5) representations are present at intermediate energies. As a concrete example which makes use of this feature, we give an analytic description of the phenomenology of a constrained NMSSM close to a Peccei-Quinn symmetry point. The related pseudo-Goldstone boson appears in decays of the Higgs bosons and possibly of the lightest neutralino, and itself decays into (b anti-b) and (tau anti-tau).
0911.1134
Sebastian Cassel
S. Cassel, D. M. Ghilencea, G. G. Ross
Testing SUSY
12 pages, 7 figures; references added, figures updated for extended parameter space scan
Phys.Lett.B687:214-218,2010
10.1016/j.physletb.2010.03.032
OUTP-0924P, CERN-PH-TH-2009-209
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If SUSY provides a solution to the hierarchy problem then supersymmetric states should not be too heavy. This requirement is quantified by a fine tuning measure that provides a quantitative test of SUSY as a solution to the hierarchy problem. The measure is useful in correlating the impact of the various experimental measurements relevant to the search for supersymmetry and also in identifying the most sensitive measurements for testing SUSY. In this paper we apply the measure to the CMSSM, computing it to two-loop order and taking account of current experimental limits and the constraint on dark matter abundance. Using this we determine the present limits on the CMSSM parameter space and identify the measurements at the LHC that are most significant in covering the remaining parameter space. Without imposing the LEP Higgs mass bound we show that the smallest fine tuning (1:13) consistent with a relic density within the WMAP bound corresponds to a Higgs mass of 114$\pm$2 GeV. Fine tuning rises rapidly for heavier Higgs.
[ { "created": "Fri, 6 Nov 2009 10:13:06 GMT", "version": "v1" }, { "created": "Wed, 24 Feb 2010 17:14:02 GMT", "version": "v2" } ]
2010-05-07
[ [ "Cassel", "S.", "" ], [ "Ghilencea", "D. M.", "" ], [ "Ross", "G. G.", "" ] ]
If SUSY provides a solution to the hierarchy problem then supersymmetric states should not be too heavy. This requirement is quantified by a fine tuning measure that provides a quantitative test of SUSY as a solution to the hierarchy problem. The measure is useful in correlating the impact of the various experimental measurements relevant to the search for supersymmetry and also in identifying the most sensitive measurements for testing SUSY. In this paper we apply the measure to the CMSSM, computing it to two-loop order and taking account of current experimental limits and the constraint on dark matter abundance. Using this we determine the present limits on the CMSSM parameter space and identify the measurements at the LHC that are most significant in covering the remaining parameter space. Without imposing the LEP Higgs mass bound we show that the smallest fine tuning (1:13) consistent with a relic density within the WMAP bound corresponds to a Higgs mass of 114$\pm$2 GeV. Fine tuning rises rapidly for heavier Higgs.
1007.0075
Hiroshi Yokoya
Yukinari Sumino, Hiroshi Yokoya
Bound-state effects on kinematical distributions of top quarks at hadron colliders
40 pages, 25 figures; minor corrections, references added; a typo in Eq. (B.9) corrected
JHEP 1009:034,2010
10.1007/JHEP09(2010)034
TU-867; CERN-PH-TH-2010-147
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
First we present a theoretical framework to compute the fully differential cross sections for the top-quark productions and their subsequent decays at hadron colliders, incorporating the bound-state effects which are important in the t\bar{t} threshold region. We include the bound-state effects such that the cross sections are correct in the LO approximation both in the threshold and high-energy regions. Then, based on this framework we compute various kinematical distributions of top quarks as well as of their decay products at the LHC, by means of Monte-Carlo event-generation. These are compared with the corresponding predictions based on conventional perturbative QCD. In particular, we find a characteristic bound-state effect on the (bW^+)-(\bar{b}W^-) double-invariant-mass distribution, which is deformed to the lower invariant-mass side in a correlated manner.
[ { "created": "Thu, 1 Jul 2010 06:39:38 GMT", "version": "v1" }, { "created": "Mon, 16 Aug 2010 22:44:03 GMT", "version": "v2" }, { "created": "Tue, 7 Jun 2016 14:01:21 GMT", "version": "v3" } ]
2016-06-08
[ [ "Sumino", "Yukinari", "" ], [ "Yokoya", "Hiroshi", "" ] ]
First we present a theoretical framework to compute the fully differential cross sections for the top-quark productions and their subsequent decays at hadron colliders, incorporating the bound-state effects which are important in the t\bar{t} threshold region. We include the bound-state effects such that the cross sections are correct in the LO approximation both in the threshold and high-energy regions. Then, based on this framework we compute various kinematical distributions of top quarks as well as of their decay products at the LHC, by means of Monte-Carlo event-generation. These are compared with the corresponding predictions based on conventional perturbative QCD. In particular, we find a characteristic bound-state effect on the (bW^+)-(\bar{b}W^-) double-invariant-mass distribution, which is deformed to the lower invariant-mass side in a correlated manner.
1311.4247
Eugenio Del Nobile
Eugenio Del Nobile, Graciela B. Gelmini, Paolo Gondolo, Ji-Haeng Huh
Update on Light WIMP Limits: LUX, lite and Light
15 pages, 15 figures. v2: minor revisions and CoGeNT 2014 data added
null
10.1088/1475-7516/2014/03/014
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We reexamine the current direct dark matter data including the recent CDMSlite and LUX data, assuming that the dark matter consists of light WIMPs, with mass close to 10 GeV/$c^2$ with spin-independent and isospin-conserving or isospin-violating interactions. We compare the data with a standard model for the dark halo of our galaxy and also in a halo-independent manner. In our standard-halo analysis, we find that for isospin-conserving couplings, CDMSlite and LUX together exclude the DAMA, CoGeNT, CDMS-II-Si, and CRESST-II possible WIMP signal regions. For isospin-violating couplings instead, we find that a substantial portion of the CDMS-II-Si region is compatible with all exclusion limits. In our halo-independent analysis, we find that for isospin-conserving couplings, the situation is of strong tension between the positive and negative results, as it was before the LUX and CDMSlite bounds, which turn out to exclude the same possible WIMP signals as previous limits. For isospin-violating couplings, we find that LUX and CDMS-II-Si bounds together exclude or severely constrain the DAMA, CoGeNT and CRESST-II possible WIMP signals.
[ { "created": "Mon, 18 Nov 2013 02:39:03 GMT", "version": "v1" }, { "created": "Tue, 4 Feb 2014 00:47:34 GMT", "version": "v2" } ]
2015-06-17
[ [ "Del Nobile", "Eugenio", "" ], [ "Gelmini", "Graciela B.", "" ], [ "Gondolo", "Paolo", "" ], [ "Huh", "Ji-Haeng", "" ] ]
We reexamine the current direct dark matter data including the recent CDMSlite and LUX data, assuming that the dark matter consists of light WIMPs, with mass close to 10 GeV/$c^2$ with spin-independent and isospin-conserving or isospin-violating interactions. We compare the data with a standard model for the dark halo of our galaxy and also in a halo-independent manner. In our standard-halo analysis, we find that for isospin-conserving couplings, CDMSlite and LUX together exclude the DAMA, CoGeNT, CDMS-II-Si, and CRESST-II possible WIMP signal regions. For isospin-violating couplings instead, we find that a substantial portion of the CDMS-II-Si region is compatible with all exclusion limits. In our halo-independent analysis, we find that for isospin-conserving couplings, the situation is of strong tension between the positive and negative results, as it was before the LUX and CDMSlite bounds, which turn out to exclude the same possible WIMP signals as previous limits. For isospin-violating couplings, we find that LUX and CDMS-II-Si bounds together exclude or severely constrain the DAMA, CoGeNT and CRESST-II possible WIMP signals.
2207.11308
Luis A Delgadillo
Rub\'en Cordero, Luis A. Delgadillo, O. G. Miranda
European Spallation Source as a searching tool for an ultralight scalar field
27 pages, 3 figures. Section added, extended discussion. To appear in PRD
null
10.1103/PhysRevD.107.075023
null
hep-ph astro-ph.HE gr-qc hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Dark matter (DM) nature is one of the major issues in physics. The search for a DM candidate has motivated the known proposal of an ultralight scalar field (ULSF). We explore the possibility to search for this ULSF at the upcoming European Spallation Source neutrino Super-Beam experiment. We have considered the recent study case in which there could be an interaction between the ULSF and active neutrinos. We have found that in this future experimental setup, the sensitivity is competitive with other neutrino physics experiments. We show the expected future sensitivity for the main parameter modeling the interaction between ULSF and neutrinos.
[ { "created": "Fri, 22 Jul 2022 19:33:02 GMT", "version": "v1" }, { "created": "Wed, 19 Apr 2023 00:01:55 GMT", "version": "v2" } ]
2023-05-03
[ [ "Cordero", "Rubén", "" ], [ "Delgadillo", "Luis A.", "" ], [ "Miranda", "O. G.", "" ] ]
Dark matter (DM) nature is one of the major issues in physics. The search for a DM candidate has motivated the known proposal of an ultralight scalar field (ULSF). We explore the possibility to search for this ULSF at the upcoming European Spallation Source neutrino Super-Beam experiment. We have considered the recent study case in which there could be an interaction between the ULSF and active neutrinos. We have found that in this future experimental setup, the sensitivity is competitive with other neutrino physics experiments. We show the expected future sensitivity for the main parameter modeling the interaction between ULSF and neutrinos.
2404.14677
Ahmed Hammad
A. Hammad and Mihoko M. Nojiri
Streamlined jet tagging network assisted by jet prong structure
Published version
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Attention-based transformer models have become increasingly prevalent in collider analysis, offering enhanced performance for tasks such as jet tagging. However, they are computationally intensive and require substantial data for training. In this paper, we introduce a new jet classification network using an MLP mixer, where two subsequent MLP operations serve to transform particle and feature tokens over the jet constituents. The transformed particles are combined with subjet information using multi-head cross-attention so that the network is invariant under the permutation of the jet constituents. We utilize two clustering algorithms to identify subjets: the standard sequential recombination algorithms with fixed radius parameters and a new IRC-safe, density-based algorithm of dynamic radii based on HDBSCAN. The proposed network demonstrates comparable classification performance to state-of-the-art models while boosting computational efficiency drastically. Finally, we evaluate the network performance using various interpretable methods, including centred kernel alignment and attention maps, to highlight network efficacy in collider analysis tasks.
[ { "created": "Tue, 23 Apr 2024 02:05:18 GMT", "version": "v1" }, { "created": "Tue, 7 May 2024 02:37:48 GMT", "version": "v2" }, { "created": "Mon, 3 Jun 2024 07:28:05 GMT", "version": "v3" } ]
2024-06-04
[ [ "Hammad", "A.", "" ], [ "Nojiri", "Mihoko M.", "" ] ]
Attention-based transformer models have become increasingly prevalent in collider analysis, offering enhanced performance for tasks such as jet tagging. However, they are computationally intensive and require substantial data for training. In this paper, we introduce a new jet classification network using an MLP mixer, where two subsequent MLP operations serve to transform particle and feature tokens over the jet constituents. The transformed particles are combined with subjet information using multi-head cross-attention so that the network is invariant under the permutation of the jet constituents. We utilize two clustering algorithms to identify subjets: the standard sequential recombination algorithms with fixed radius parameters and a new IRC-safe, density-based algorithm of dynamic radii based on HDBSCAN. The proposed network demonstrates comparable classification performance to state-of-the-art models while boosting computational efficiency drastically. Finally, we evaluate the network performance using various interpretable methods, including centred kernel alignment and attention maps, to highlight network efficacy in collider analysis tasks.
1301.4652
Tho Hue Le
L. T. Hue, D. T. Huong and H. N. Long
Lepton flavor violating processes \tau ->\mu\gamma$, $\tau-> 3\mu$ and $Z-> \mu\tau$ in the Supersymmetric economical 3-3-1 model
$B/\mu$-type parameters are included to guarantee the vacuum stability condition as well as satisfy current electroweak precision test. Mass parameter of gaugino in numerical investigation is shifted to be larger than 300 GeV. Few conclusions are changed. New references are added. This version was accepted by Nuclear Physics B
Nucl.Phys.B 873 (2013) 207-247
10.1016/j.nuclphysb.2013.04.014
null
hep-ph
http://creativecommons.org/licenses/publicdomain/
In this work, we study the charged lepton flavor violating (cLFV) decays $\tau-> \mu\gamma$, $\tau-> 3\mu$ and $Z->\mu\tau$ in the framework of the Supersymmetric economical 3-3-1 model. Analytic formulas for branching ratios (BR) of these decays are presented. We assume that there exist lepton flavor violation (LFV) sources in both right- and left-handed slepton sectors. This leads to the strong enhancement of cLFV decay rates. We also show that the effects of the LFV source to the cLFV decay rates in the left-handed slepton sector are greater than those in the right- handed slepton sector. By numerical investigation, we show that the model under consideration contains the relative light mass spectrum of sleptons which satisfies the current experimental bounds on LFV processes in the limit of small $\tan \gamma$. The interplay between monopole and dipole operators also was studied.
[ { "created": "Sun, 20 Jan 2013 11:24:23 GMT", "version": "v1" }, { "created": "Tue, 22 Jan 2013 03:14:49 GMT", "version": "v2" }, { "created": "Wed, 24 Apr 2013 09:16:51 GMT", "version": "v3" } ]
2013-05-06
[ [ "Hue", "L. T.", "" ], [ "Huong", "D. T.", "" ], [ "Long", "H. N.", "" ] ]
In this work, we study the charged lepton flavor violating (cLFV) decays $\tau-> \mu\gamma$, $\tau-> 3\mu$ and $Z->\mu\tau$ in the framework of the Supersymmetric economical 3-3-1 model. Analytic formulas for branching ratios (BR) of these decays are presented. We assume that there exist lepton flavor violation (LFV) sources in both right- and left-handed slepton sectors. This leads to the strong enhancement of cLFV decay rates. We also show that the effects of the LFV source to the cLFV decay rates in the left-handed slepton sector are greater than those in the right- handed slepton sector. By numerical investigation, we show that the model under consideration contains the relative light mass spectrum of sleptons which satisfies the current experimental bounds on LFV processes in the limit of small $\tan \gamma$. The interplay between monopole and dipole operators also was studied.
hep-ph/0004204
Mohan
Mohan Narayan and S. Uma Sankar (Department of Physics, I.I.T. Bombay, India)
Matter effects for `just so' oscillations
11 pages including one figure
null
null
null
hep-ph
null
We study the effect of the matter term on the evolution of the solar neutrinos when the neutrino parameters are those of the `just-so' case. The extreme non-adiabatic effects at the edge of the sun reduce the expression for the survival probability in the just-so case to that of the vacuum case. This conclusion is independent of the width of the extreme non-adiabatic region, which is a function of the density profile of the sun beyond $r > 0.9 R_s$. However, in its propagation, neutrino encounters regions of moderate (non-extreme) non-adiabticity. Neutrino traversal through these regions give corrections to the survival probability which are profile dependent.
[ { "created": "Fri, 21 Apr 2000 13:49:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Narayan", "Mohan", "", "Department of Physics, I.I.T. Bombay,\n India" ], [ "Sankar", "S. Uma", "", "Department of Physics, I.I.T. Bombay,\n India" ] ]
We study the effect of the matter term on the evolution of the solar neutrinos when the neutrino parameters are those of the `just-so' case. The extreme non-adiabatic effects at the edge of the sun reduce the expression for the survival probability in the just-so case to that of the vacuum case. This conclusion is independent of the width of the extreme non-adiabatic region, which is a function of the density profile of the sun beyond $r > 0.9 R_s$. However, in its propagation, neutrino encounters regions of moderate (non-extreme) non-adiabticity. Neutrino traversal through these regions give corrections to the survival probability which are profile dependent.
2406.16463
Bartosz Fornal
Bartosz Fornal, Dyori Polynice, Luka Thompson
Probing the Neutrino Seesaw Scale with Gravitational Waves
9 pages, 6 figures
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
Neutrinos are the most elusive particles of the Standard Model. The physics behind their masses remains unknown and requires introducing new particles and interactions. An elegant solution to this problem is provided by the seesaw mechanism. Typically considered at a high scale, it is potentially testable in gravitational wave experiments by searching for a spectrum from cosmic strings, which offers a rather generic signature across many high-scale seesaw models. Here we consider the possibility of a low-scale seesaw mechanism at the PeV scale, generating neutrino masses within the framework of a model with gauged U(1) lepton number. In this case, the gravitational wave signal at high frequencies arises from a first order phase transition in the early Universe, whereas at low frequencies it is generated by domain wall annihilation, leading to a double-peaked structure in the gravitational wave spectrum. The signals discussed here can be searched for in upcoming experiments, including gravitational wave interferometers, pulsar timing arrays, and astrometry observations.
[ { "created": "Mon, 24 Jun 2024 09:09:09 GMT", "version": "v1" } ]
2024-06-25
[ [ "Fornal", "Bartosz", "" ], [ "Polynice", "Dyori", "" ], [ "Thompson", "Luka", "" ] ]
Neutrinos are the most elusive particles of the Standard Model. The physics behind their masses remains unknown and requires introducing new particles and interactions. An elegant solution to this problem is provided by the seesaw mechanism. Typically considered at a high scale, it is potentially testable in gravitational wave experiments by searching for a spectrum from cosmic strings, which offers a rather generic signature across many high-scale seesaw models. Here we consider the possibility of a low-scale seesaw mechanism at the PeV scale, generating neutrino masses within the framework of a model with gauged U(1) lepton number. In this case, the gravitational wave signal at high frequencies arises from a first order phase transition in the early Universe, whereas at low frequencies it is generated by domain wall annihilation, leading to a double-peaked structure in the gravitational wave spectrum. The signals discussed here can be searched for in upcoming experiments, including gravitational wave interferometers, pulsar timing arrays, and astrometry observations.
hep-ph/9811434
Stefan Dittmaier
Stefan Dittmaier
Radiative corrections to W-pair production in e+e- annihilation
16 pages, latex, 4 postscript figures, contribution to the proceedings of "IVth International Symposium on Radiative Corrections, RADCOR 98", September 1998, Barcelona, Spain
null
null
CERN-TH/98-336
hep-ph
null
The status of precision calculations for the processes e+e- --> WW --> 4 fermions is reviewed, paying particular attention to questions of gauge invariance and recent progress concerning photonic radiative corrections.
[ { "created": "Mon, 23 Nov 1998 10:06:54 GMT", "version": "v1" } ]
2007-05-23
[ [ "Dittmaier", "Stefan", "" ] ]
The status of precision calculations for the processes e+e- --> WW --> 4 fermions is reviewed, paying particular attention to questions of gauge invariance and recent progress concerning photonic radiative corrections.
hep-ph/9903474
Werner Porod
L. Navarro (Uni. Valencia), W. Porod (Uni. Vienna), and J.W.F. Valle (Uni. Valencia)
Top-Quark Phenomenology in Models with Bilinearly and Spontaneously Broken R-parity
12 pages, 6 eps-figures
Phys.Lett.B459:615-624,1999
10.1016/S0370-2693(99)00728-5
FTUV/99-16, IFIC/99-17, UWThPh-1999-18
hep-ph hep-ex
null
We study unconventional decays of the top-quark in the framework of SUSY models with spontaneously broken R-parity. In particular we discuss an effective theory which consists of the MSSM plus bilinearly broken R-parity. We demonstrate that the decay modes t -> stau + b and t -> tau + sbottom can have large branching ratios even in scenarios where the tau-neutrino mass is very small. We show that existing Tevatron data already probe the theoretical parameters, with promising prospects for further improvement at the Run 2 of the Tevatron.
[ { "created": "Wed, 24 Mar 1999 18:05:12 GMT", "version": "v1" } ]
2009-09-17
[ [ "Navarro", "L.", "", "Uni. Valencia" ], [ "Porod", "W.", "", "Uni. Vienna" ], [ "Valle", "J. W. F.", "", "Uni. Valencia" ] ]
We study unconventional decays of the top-quark in the framework of SUSY models with spontaneously broken R-parity. In particular we discuss an effective theory which consists of the MSSM plus bilinearly broken R-parity. We demonstrate that the decay modes t -> stau + b and t -> tau + sbottom can have large branching ratios even in scenarios where the tau-neutrino mass is very small. We show that existing Tevatron data already probe the theoretical parameters, with promising prospects for further improvement at the Run 2 of the Tevatron.
hep-ph/9305248
null
Howard E. Haber
When Are Radiative Corrections Important in the Minimal Supersymmetric Model?
52 pages, SCIPP-93/06, phyzzx format (must process twice to get no TeX errors)
null
null
null
hep-ph
null
Precision electroweak measurements at LEP currently check the validity of the Standard Model to about one part in a thousand. Any successful model of physics beyond the Standard Model must be consistent with these observations. The impact of radiative corrections on the Minimal Supersymmetric Model (MSSM) is considered. The influence of supersymmetric particles on precision electroweak measurements is generally negligible since radiative corrections mediated by supersymmetric particles are suppressed by a factor of order $m_Z^2/M_{\rm SUSY}^2$ (where $M_{\rm SUSY}$ is the scale characterizing the scale of supersymmetric particle masses). However, there are a few pertinent exceptions. For example, the radiative corrections to the rare decay $b\to s\gamma$ from charged Higgs and supersymmetric particle exchange can be of the same order as the Standard Model contribution. Large radiative corrections also lead to modifications of MSSM tree-level (natural) relations. The largest corrections of this type occur in the MSSM Higgs sector and are enhanced by powers of the top quark mass. The consequences of the radiatively corrected MSSM Higgs sector are briefly discussed.
[ { "created": "Wed, 12 May 1993 02:18:00 GMT", "version": "v1" } ]
2007-05-23
[ [ "Haber", "Howard E.", "" ] ]
Precision electroweak measurements at LEP currently check the validity of the Standard Model to about one part in a thousand. Any successful model of physics beyond the Standard Model must be consistent with these observations. The impact of radiative corrections on the Minimal Supersymmetric Model (MSSM) is considered. The influence of supersymmetric particles on precision electroweak measurements is generally negligible since radiative corrections mediated by supersymmetric particles are suppressed by a factor of order $m_Z^2/M_{\rm SUSY}^2$ (where $M_{\rm SUSY}$ is the scale characterizing the scale of supersymmetric particle masses). However, there are a few pertinent exceptions. For example, the radiative corrections to the rare decay $b\to s\gamma$ from charged Higgs and supersymmetric particle exchange can be of the same order as the Standard Model contribution. Large radiative corrections also lead to modifications of MSSM tree-level (natural) relations. The largest corrections of this type occur in the MSSM Higgs sector and are enhanced by powers of the top quark mass. The consequences of the radiatively corrected MSSM Higgs sector are briefly discussed.
1203.1916
Emil Avsar
Emil Avsar
TMD factorization and the gluon distribution in high energy QCD
80 pages v2: Few typos corrected, and references added
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This paper is a part of a series of works where we in detail examine the concept of Transverse Momentum Dependent (TMD), or k_T, factorization, which is frequently encountered in the literature and is widely used in the phenomenological applications of QCD at very high energies. We address the question of what exactly factorization is, as it is meant in different contexts and formalisms, and we compare the formalisms to each other. We clarify some basic concepts regarding factorization and how it exactly is applied in high energy QCD, and we make important notes on some key and fundamental points that are often overlooked. We offer an extensive analysis of single inclusive particle production, and we analyze the TMD gluon distribution that plays a pivotal role in high energy QCD.
[ { "created": "Thu, 8 Mar 2012 20:48:27 GMT", "version": "v1" }, { "created": "Mon, 2 Apr 2012 17:44:08 GMT", "version": "v2" } ]
2012-04-03
[ [ "Avsar", "Emil", "" ] ]
This paper is a part of a series of works where we in detail examine the concept of Transverse Momentum Dependent (TMD), or k_T, factorization, which is frequently encountered in the literature and is widely used in the phenomenological applications of QCD at very high energies. We address the question of what exactly factorization is, as it is meant in different contexts and formalisms, and we compare the formalisms to each other. We clarify some basic concepts regarding factorization and how it exactly is applied in high energy QCD, and we make important notes on some key and fundamental points that are often overlooked. We offer an extensive analysis of single inclusive particle production, and we analyze the TMD gluon distribution that plays a pivotal role in high energy QCD.
1702.05727
Mahdi Radin
M. Radin
Charmonium Mass Spectrum with Spin-Dependent Interaction in Momentum-Helicity Space
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we have solved the nonrelativistic form of the Lippmann-Schwinger equation in the momentum-helicity space by inserting a spin-dependent quark-antiquark potential model numerically. To this end, we have used the momentum-helicity basis states for describing a nonrelativistic reduction of one gluon exchange potential. Then we have calculated the mass spectrum of the charmonium $\psi(c\bar{c})$, and finally we have compared the results with the another theoretical results and experimental data.
[ { "created": "Sun, 19 Feb 2017 09:29:09 GMT", "version": "v1" } ]
2017-02-21
[ [ "Radin", "M.", "" ] ]
In this paper we have solved the nonrelativistic form of the Lippmann-Schwinger equation in the momentum-helicity space by inserting a spin-dependent quark-antiquark potential model numerically. To this end, we have used the momentum-helicity basis states for describing a nonrelativistic reduction of one gluon exchange potential. Then we have calculated the mass spectrum of the charmonium $\psi(c\bar{c})$, and finally we have compared the results with the another theoretical results and experimental data.
hep-ph/9908294
Saswati Sarkar
Asim K. Ray and Saswati Sarkar (Visva Bharati University, INDIA)
An $SU(2)_{L}\times U(1)_{Y} \times S_{3} \times D$ model for atmospheric and solar neutrino deficits
null
Phys.Rev. D61 (2000) 035007
10.1103/PhysRevD.61.035007
null
hep-ph
null
Motivated by the recent Super-Kamiokande experiment on atmospheric and solar neutrino oscillation we propose a see-saw model of three generations of neutrinos based on the gauge group $SU(2)_{L}\times U(1)_{Y}$ with discrete symmetries $(S_{3} \times D)$ and three right handed singlet neutrinos so that this model can accommodate the recent Super-Kamiokande data on atmospheric and solar neutrino oscillations. The model predicts maximal mixing between $\nu_{\mu}$ and $\nu_{\tau}$ with $sin^{2}2{\theta_{\mu\tau}}$ = 1 as required by the atmospheric neutrino data and small mixing between $\nu_{e}$ and $\nu_{\mu}$ with $sin^{2}2{\theta_{e\mu}} \sim (10^{-2}-10^{-3})$ as a possible explanation of the solar neutrino deficit through the MSW mechanism. The model admits two mass scales of which one breaks the electroweak symmetry and the other is responsible for the breaking of the lepton number symmetry at GUT scale leading to small Majorana mass of the left handed doublet neutrinos.
[ { "created": "Sat, 7 Aug 1999 11:06:50 GMT", "version": "v1" }, { "created": "Fri, 3 Sep 1999 07:44:00 GMT", "version": "v2" } ]
2009-10-31
[ [ "Ray", "Asim K.", "", "Visva Bharati University, INDIA" ], [ "Sarkar", "Saswati", "", "Visva Bharati University, INDIA" ] ]
Motivated by the recent Super-Kamiokande experiment on atmospheric and solar neutrino oscillation we propose a see-saw model of three generations of neutrinos based on the gauge group $SU(2)_{L}\times U(1)_{Y}$ with discrete symmetries $(S_{3} \times D)$ and three right handed singlet neutrinos so that this model can accommodate the recent Super-Kamiokande data on atmospheric and solar neutrino oscillations. The model predicts maximal mixing between $\nu_{\mu}$ and $\nu_{\tau}$ with $sin^{2}2{\theta_{\mu\tau}}$ = 1 as required by the atmospheric neutrino data and small mixing between $\nu_{e}$ and $\nu_{\mu}$ with $sin^{2}2{\theta_{e\mu}} \sim (10^{-2}-10^{-3})$ as a possible explanation of the solar neutrino deficit through the MSW mechanism. The model admits two mass scales of which one breaks the electroweak symmetry and the other is responsible for the breaking of the lepton number symmetry at GUT scale leading to small Majorana mass of the left handed doublet neutrinos.
0712.2514
Andrei Kataev
A.L. Kataev (INR, Moscow) and V.T. Kim (NPI, Gatchina)
Higgs Decay To \bar{b}b: Different Approaches To Resummation Of QCD Effects
4 pages, 2 figures, submitted tio the Proceedings of 13 Lomonosov Conference on Elementary Particle Physics, Moscow State University, August 23-29, 2007, 1 reference corrected
null
null
null
hep-ph
null
The comparison between parameterisations of the perturbation results for the decay width of the Standard Model Higgs boson to \bar{b}b-quarks pairs, based on application of \bar{MS}-scheme running quark mass and pole b-quark mass, are presented. In the case of the latter parameterisation taking into account of order O(\alpha_s^3) term is rather important. It is minimising deviations of the results obtained at the O(\alpha_s^2) level from the results, which follow from the running quark mass approach
[ { "created": "Sat, 15 Dec 2007 13:58:53 GMT", "version": "v1" }, { "created": "Sun, 23 Dec 2007 18:49:09 GMT", "version": "v2" } ]
2007-12-23
[ [ "Kataev", "A. L.", "", "INR, Moscow" ], [ "Kim", "V. T.", "", "NPI, Gatchina" ] ]
The comparison between parameterisations of the perturbation results for the decay width of the Standard Model Higgs boson to \bar{b}b-quarks pairs, based on application of \bar{MS}-scheme running quark mass and pole b-quark mass, are presented. In the case of the latter parameterisation taking into account of order O(\alpha_s^3) term is rather important. It is minimising deviations of the results obtained at the O(\alpha_s^2) level from the results, which follow from the running quark mass approach
0802.1486
Alexey Gulov
A. N. Buryk, V. V. Skalozub
Neural network predictions for Z' boson within LEP2 data set of Bhabha process
12 pages, 6 figures; results of all the LEP2 collaborations were analysed
null
null
null
hep-ph
http://creativecommons.org/licenses/by/3.0/
The neural network approach is applied to search for the Z'-boson within the LEP2 data set for e+ e- -> e+ e- scattering process. In the course of the analysis, the data set is reduced by 20 percent. The axial-vector and vector couplings of the Z' are estimated at 95 percent CL within a two-parameter fit. The mass is determined to be 0.53-1.05 TeV. Comparisons with other results are given.
[ { "created": "Mon, 11 Feb 2008 17:53:11 GMT", "version": "v1" }, { "created": "Fri, 15 May 2009 16:09:06 GMT", "version": "v2" } ]
2009-05-15
[ [ "Buryk", "A. N.", "" ], [ "Skalozub", "V. V.", "" ] ]
The neural network approach is applied to search for the Z'-boson within the LEP2 data set for e+ e- -> e+ e- scattering process. In the course of the analysis, the data set is reduced by 20 percent. The axial-vector and vector couplings of the Z' are estimated at 95 percent CL within a two-parameter fit. The mass is determined to be 0.53-1.05 TeV. Comparisons with other results are given.
hep-ph/0603164
Olga Lakhina
O. Lakhina, E. S. Swanson (U. Pittsburgh)
Dynamic Properties of Charmonium
22 pages, 22 ps figures (table entries corrected, text modified)
Phys.Rev.D74:014012,2006
10.1103/PhysRevD.74.014012
null
hep-ph
null
Nonrelativistic quark models of charmonia are tested by comparison of theoretical charmonium decay constants, form factors, and $\gamma\gamma$ widths with experiment and lattice gauge computations. The importance of relativistic effects, a running coupling, and the correct implementation of bound state effects are demonstrated. We describe how an improved model and computational techniques resolve several outstanding issues in previous nonrelativistic quark models such as the use of `correction' factors in quark model form factors, artificial energy prescriptions in decay constant calculations, and ad hoc phase space modifications. We comment on the small experimental value of $f_{\psi''}$ and the D-wave component of the $J/\psi$. Decay constants and $\gamma\gamma$ widths for bottomonium are also presented.
[ { "created": "Tue, 21 Mar 2006 17:45:04 GMT", "version": "v1" }, { "created": "Tue, 28 Mar 2006 19:26:41 GMT", "version": "v2" } ]
2008-11-26
[ [ "Lakhina", "O.", "", "U. Pittsburgh" ], [ "Swanson", "E. S.", "", "U. Pittsburgh" ] ]
Nonrelativistic quark models of charmonia are tested by comparison of theoretical charmonium decay constants, form factors, and $\gamma\gamma$ widths with experiment and lattice gauge computations. The importance of relativistic effects, a running coupling, and the correct implementation of bound state effects are demonstrated. We describe how an improved model and computational techniques resolve several outstanding issues in previous nonrelativistic quark models such as the use of `correction' factors in quark model form factors, artificial energy prescriptions in decay constant calculations, and ad hoc phase space modifications. We comment on the small experimental value of $f_{\psi''}$ and the D-wave component of the $J/\psi$. Decay constants and $\gamma\gamma$ widths for bottomonium are also presented.
hep-ph/9604297
Maksim L. Nekrasov
M. L. Nekrasov (IHEP, Protvino)
Pseudoscalar Glueball, eta'-meson and its Excitation in the Chiral Effective Lagrangian
19 pages LaTeX, no figures. Revised version accepted in Phis.Rev.D
Phys.Rev. D56 (1997) 5681-5691
10.1103/PhysRevD.56.5681
null
hep-ph
null
A generalization of the chiral effective lagrangian of order $p^2$ is proposed which involves the $\eta'$-meson, its excitation, and the pseudoscalar (PS) glueball. Model-independent constraints are found for the contributions to the lagrangian of the above singlet states. Those allow one to independently identify the nature of these singlet states in the framework of the approach. The mixing among the iso-singlet states (including $\eta^8$-state) is analysed, and the hierarchy of the mixing angles is described which is defined by the chiral and large-$N_c$ expansions. The recent PCAC results are reproduced, which are related to the problem of the renormalization-group invariant description of the $\eta'$ and the PS glueball, and a further analysis of this problem is performed.
[ { "created": "Thu, 11 Apr 1996 19:52:48 GMT", "version": "v1" }, { "created": "Thu, 17 Jul 1997 10:24:39 GMT", "version": "v2" } ]
2009-10-28
[ [ "Nekrasov", "M. L.", "", "IHEP, Protvino" ] ]
A generalization of the chiral effective lagrangian of order $p^2$ is proposed which involves the $\eta'$-meson, its excitation, and the pseudoscalar (PS) glueball. Model-independent constraints are found for the contributions to the lagrangian of the above singlet states. Those allow one to independently identify the nature of these singlet states in the framework of the approach. The mixing among the iso-singlet states (including $\eta^8$-state) is analysed, and the hierarchy of the mixing angles is described which is defined by the chiral and large-$N_c$ expansions. The recent PCAC results are reproduced, which are related to the problem of the renormalization-group invariant description of the $\eta'$ and the PS glueball, and a further analysis of this problem is performed.
2212.08025
Rahool Kumar Barman
K. S. Babu, Rahool Kumar Barman, Dorival Gon\c{c}alves and Ahmed Ismail
Probing Lepton Number Violation and Majorana Nature of Neutrinos at the LHC
10 pages, 8 figures, and 1 table
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
Observation of lepton number ($L$) violation by two units at colliders would provide evidence for the Majorana nature of neutrinos. We study signals of $L$-violation in the context of two popular models of neutrino masses, the type-II seesaw model and the Zee model, wherein small neutrino masses arise at the tree-level and one-loop level, respectively. We focus on $L$-violation signals at the LHC arising through the process $pp \to \ell^{\pm}\ell^{\prime \pm}$ + jets within these frameworks. We obtain sensitivity to $L$-violation in the type-II seesaw model for triplet scalar masses up to 700 GeV and in the Zee model for charged scalar masses up to 4.8 TeV at the high-luminosity LHC with an integrated luminosity of $3~\text{ab}^{-1}$.
[ { "created": "Thu, 15 Dec 2022 18:34:04 GMT", "version": "v1" } ]
2022-12-16
[ [ "Babu", "K. S.", "" ], [ "Barman", "Rahool Kumar", "" ], [ "Gonçalves", "Dorival", "" ], [ "Ismail", "Ahmed", "" ] ]
Observation of lepton number ($L$) violation by two units at colliders would provide evidence for the Majorana nature of neutrinos. We study signals of $L$-violation in the context of two popular models of neutrino masses, the type-II seesaw model and the Zee model, wherein small neutrino masses arise at the tree-level and one-loop level, respectively. We focus on $L$-violation signals at the LHC arising through the process $pp \to \ell^{\pm}\ell^{\prime \pm}$ + jets within these frameworks. We obtain sensitivity to $L$-violation in the type-II seesaw model for triplet scalar masses up to 700 GeV and in the Zee model for charged scalar masses up to 4.8 TeV at the high-luminosity LHC with an integrated luminosity of $3~\text{ab}^{-1}$.
0905.2483
Atsushi Watanabe
Raj Gandhi, Abhijit Samanta, Atsushi Watanabe
The Role and Detectability of the Charm Contribution to Ultra High Energy Neutrino Fluxes
13 pages, 5 figures; (ver. 2) accepted in JCAP
JCAP 0909:015,2009
10.1088/1475-7516/2009/09/015
KYUSHU-HET-118
hep-ph astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is widely believed that charm meson production and decay may play an important role in high energy astrophysical sources of neutrinos, especially those that are baryon-rich, providing an environment conducive to pp interactions. Using slow-jet supernovae (SJS) as an example of such a source, we study the detectability of high-energy neutrinos, paying particular attention to those produced from charmed-mesons. We highlight important distinguishing features in the ultra-high energy neutrino flux which would act as markers for the role of charm in the source. In particular, charm leads to significant event rates at higher energies, after the conventional (pi, K) neutrino fluxes fall off. We calculate event rates both for a nearby single source and for diffuse SJS fluxes for an IceCube-like detector. By comparing muon event rates for the conventional and prompt fluxes in different energy bins, we demonstrate the striking energy dependence in the rates induced by the presence of charm. We also show that it leads to an energy dependant flux ratio of shower to muon events, providing an additional important diagnostic tool for the presence of prompt neutrinos. Motivated by the infusion of high energy anti-electron neutrinos into the flux by charm decay, we also study the detectability of the Glashow resonance due to these sources.
[ { "created": "Fri, 15 May 2009 07:16:44 GMT", "version": "v1" }, { "created": "Thu, 27 Aug 2009 02:42:36 GMT", "version": "v2" } ]
2009-09-28
[ [ "Gandhi", "Raj", "" ], [ "Samanta", "Abhijit", "" ], [ "Watanabe", "Atsushi", "" ] ]
It is widely believed that charm meson production and decay may play an important role in high energy astrophysical sources of neutrinos, especially those that are baryon-rich, providing an environment conducive to pp interactions. Using slow-jet supernovae (SJS) as an example of such a source, we study the detectability of high-energy neutrinos, paying particular attention to those produced from charmed-mesons. We highlight important distinguishing features in the ultra-high energy neutrino flux which would act as markers for the role of charm in the source. In particular, charm leads to significant event rates at higher energies, after the conventional (pi, K) neutrino fluxes fall off. We calculate event rates both for a nearby single source and for diffuse SJS fluxes for an IceCube-like detector. By comparing muon event rates for the conventional and prompt fluxes in different energy bins, we demonstrate the striking energy dependence in the rates induced by the presence of charm. We also show that it leads to an energy dependant flux ratio of shower to muon events, providing an additional important diagnostic tool for the presence of prompt neutrinos. Motivated by the infusion of high energy anti-electron neutrinos into the flux by charm decay, we also study the detectability of the Glashow resonance due to these sources.
1904.00238
Jan Heisig
Mathias Garny, Jan Heisig, Marco Hufnagel, Benedikt L\"ulf, Stefan Vogl
Conversion-driven freeze-out: Dark matter genesis beyond the WIMP paradigm
Contribution to the proceedings of the Corfu Summer Institute 2018; 8 pages + references, 4 figures
null
null
TUM-HEP-1195/19, CP3-19-14, DESY 19-064, TTK-19-13
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider dark matter (DM) with very weak couplings to the standard model (SM), such that its self-annihilation cross section is much smaller than the canonical one, $\langle\sigma v\rangle_{\chi\chi} \ll 10^{-26}\mathrm{cm}^3/\mathrm{s}$. In this case DM self-annihilation is negligible for the dynamics of freeze-out and DM dilution is solely driven by efficient annihilation of heavier accompanying dark sector particles provided that DM maintains chemical equilibrium with the dark sector. This chemical equilibrium is established by conversion processes which require much smaller couplings to be efficient than annihilation. The chemical decoupling of DM from the SM can either be initiated by the freeze-out of annihilation, resembling a co-annihilation scenario, or of conversion processes, leading to the scenario of conversion-driven freeze-out. We focus on the latter and discuss its distinct phenomenology.
[ { "created": "Sat, 30 Mar 2019 16:05:23 GMT", "version": "v1" } ]
2019-04-18
[ [ "Garny", "Mathias", "" ], [ "Heisig", "Jan", "" ], [ "Hufnagel", "Marco", "" ], [ "Lülf", "Benedikt", "" ], [ "Vogl", "Stefan", "" ] ]
We consider dark matter (DM) with very weak couplings to the standard model (SM), such that its self-annihilation cross section is much smaller than the canonical one, $\langle\sigma v\rangle_{\chi\chi} \ll 10^{-26}\mathrm{cm}^3/\mathrm{s}$. In this case DM self-annihilation is negligible for the dynamics of freeze-out and DM dilution is solely driven by efficient annihilation of heavier accompanying dark sector particles provided that DM maintains chemical equilibrium with the dark sector. This chemical equilibrium is established by conversion processes which require much smaller couplings to be efficient than annihilation. The chemical decoupling of DM from the SM can either be initiated by the freeze-out of annihilation, resembling a co-annihilation scenario, or of conversion processes, leading to the scenario of conversion-driven freeze-out. We focus on the latter and discuss its distinct phenomenology.
2305.11138
Partha Kumar Paul
Satyabrata Mahapatra, Partha Kumar Paul, Narendra Sahu, Prashant Shukla
Cogenesis of matter and dark matter from triplet fermion seesaw
32 pages, 19 captioned figures
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a simple model in the type-III seesaw framework to explain the neutrino mass, asymmetric dark matter, baryon asymmetry of the Universe, and the recently reported W-mass anomaly by CDF-II collaboration. We extend the standard model with a vector-like singlet lepton ($\chi$) and a hypercharge zero scalar triplet ($\Delta$) in addition to three hypercharge zero triplet fermions($\Sigma_i~,i=1,2,3$). A $Z_2$ symmetry is imposed under which $\chi$ and $\Delta$ are odd, while all other particles are even. As a result, the lightest $Z_2$ odd particle $\chi$ behaves as a candidate of dark matter. In the early Universe, the CP-violating out-of-equilibrium decay of heavy triplet fermions to the Standard Model lepton ($L$) and Higgs ($H$) generate a net lepton asymmetry, while that of triplet fermions to $\chi$ and $\Delta$ generate a net asymmetric dark matter. The lepton asymmetry is converted to the required baryon asymmetry of the Universe via the electroweak sphalerons, while the asymmetry in $\chi$ remains as a dark matter relic that we observe today. We introduce a singlet scalar $\phi$, with mass $m_\phi < m_\chi$, which not only assists to deplete the symmetric component of $\chi$ through the annihilation process: $\bar{\chi} \chi \to \phi \phi$ but also paves a path to detect dark matter $\chi$ at direct search experiments through $\phi-H$ mixing. The $Z_2$ symmetry is broken softly resulting in an unstable asymmetric dark matter with mass ranging from a few MeV to a few tens of GeV. The softly broken $Z_2$ symmetry also induces a vacuum expectation value (vev) of $\Delta$ due to which the asymmetry in $\Delta$ disappears. Moreover, the vev of $\Delta$ enhances the W-boson mass as reported by CDF-II collaboration with $7\sigma$ statistical significance, while keeping the $Z$-boson mass intact.
[ { "created": "Thu, 18 May 2023 17:34:05 GMT", "version": "v1" }, { "created": "Mon, 29 May 2023 19:33:39 GMT", "version": "v2" } ]
2023-05-31
[ [ "Mahapatra", "Satyabrata", "" ], [ "Paul", "Partha Kumar", "" ], [ "Sahu", "Narendra", "" ], [ "Shukla", "Prashant", "" ] ]
We propose a simple model in the type-III seesaw framework to explain the neutrino mass, asymmetric dark matter, baryon asymmetry of the Universe, and the recently reported W-mass anomaly by CDF-II collaboration. We extend the standard model with a vector-like singlet lepton ($\chi$) and a hypercharge zero scalar triplet ($\Delta$) in addition to three hypercharge zero triplet fermions($\Sigma_i~,i=1,2,3$). A $Z_2$ symmetry is imposed under which $\chi$ and $\Delta$ are odd, while all other particles are even. As a result, the lightest $Z_2$ odd particle $\chi$ behaves as a candidate of dark matter. In the early Universe, the CP-violating out-of-equilibrium decay of heavy triplet fermions to the Standard Model lepton ($L$) and Higgs ($H$) generate a net lepton asymmetry, while that of triplet fermions to $\chi$ and $\Delta$ generate a net asymmetric dark matter. The lepton asymmetry is converted to the required baryon asymmetry of the Universe via the electroweak sphalerons, while the asymmetry in $\chi$ remains as a dark matter relic that we observe today. We introduce a singlet scalar $\phi$, with mass $m_\phi < m_\chi$, which not only assists to deplete the symmetric component of $\chi$ through the annihilation process: $\bar{\chi} \chi \to \phi \phi$ but also paves a path to detect dark matter $\chi$ at direct search experiments through $\phi-H$ mixing. The $Z_2$ symmetry is broken softly resulting in an unstable asymmetric dark matter with mass ranging from a few MeV to a few tens of GeV. The softly broken $Z_2$ symmetry also induces a vacuum expectation value (vev) of $\Delta$ due to which the asymmetry in $\Delta$ disappears. Moreover, the vev of $\Delta$ enhances the W-boson mass as reported by CDF-II collaboration with $7\sigma$ statistical significance, while keeping the $Z$-boson mass intact.
2008.08119
Aniello Quaranta
Antonio Capolupo, Salvatore Marco Giampaolo, Aniello Quaranta
Beyond the MSW effect: Neutrinos in a dense medium
15 pages, 4 figures
Physics Letters B, Volume 820, 136489 (2021)
10.1016/j.physletb.2021.136489
null
hep-ph nucl-th
http://creativecommons.org/licenses/by-sa/4.0/
We present a theory of neutrino oscillations in a dense medium which goes beyond the effective matter potential used in the description of the MSW effect. We show how the purity of the neutrino state is degraded by neutrino interactions with the environment and how neutrino--matter interactions can be a source of decoherence. We present new oscillation formulae for neutrinos interacting with leptons and carry out a numerical analysis which exhibits deviations from the MSW formulae for propagation through the Earth of ultra-high energy neutrinos. In particular, we show that at high density and/or high neutrino energy, the vanishing transition probabilities derived for MSW effect, are non zero when the scattering is taken into account.
[ { "created": "Tue, 18 Aug 2020 18:50:41 GMT", "version": "v1" }, { "created": "Mon, 19 Jul 2021 09:55:32 GMT", "version": "v2" } ]
2021-07-20
[ [ "Capolupo", "Antonio", "" ], [ "Giampaolo", "Salvatore Marco", "" ], [ "Quaranta", "Aniello", "" ] ]
We present a theory of neutrino oscillations in a dense medium which goes beyond the effective matter potential used in the description of the MSW effect. We show how the purity of the neutrino state is degraded by neutrino interactions with the environment and how neutrino--matter interactions can be a source of decoherence. We present new oscillation formulae for neutrinos interacting with leptons and carry out a numerical analysis which exhibits deviations from the MSW formulae for propagation through the Earth of ultra-high energy neutrinos. In particular, we show that at high density and/or high neutrino energy, the vanishing transition probabilities derived for MSW effect, are non zero when the scattering is taken into account.
hep-ph/0507327
Tony Signal
A. I. Signal
g1(x) and g2(x) in the Meson Cloud Model
4 pages, contribution to DIS 05, Madison, Wisconsin
null
10.1063/1.2122198
null
hep-ph nucl-th
null
We calculate the spin dependent structure functions g1(x) and g2(x) of the proton and neutron. Our calculation uses the meson cloud model of nucleon structure and includes the effects of kinematic terms which mix transverse and longitudinal spin components. We find small corrections to the nucleon structure functions, however these are significant for the neutron.
[ { "created": "Thu, 28 Jul 2005 23:23:43 GMT", "version": "v1" } ]
2015-06-25
[ [ "Signal", "A. I.", "" ] ]
We calculate the spin dependent structure functions g1(x) and g2(x) of the proton and neutron. Our calculation uses the meson cloud model of nucleon structure and includes the effects of kinematic terms which mix transverse and longitudinal spin components. We find small corrections to the nucleon structure functions, however these are significant for the neutron.
1601.00939
Hamzeh Khanpour
Hamzeh Khanpour and S. Atashbar Tehrani
Global analysis of nuclear parton distribution functions and their uncertainties at next-to-next-to-leading order
19 Pages, 24 Figures, 3 Tables
Phys. Rev. D 93, 014026 (2016)
10.1103/PhysRevD.93.014026
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform a next-to-next-to-leading order (NNLO) analysis of nuclear parton distribution functions (nPDFs) using neutral current charged-lepton ($\ell ^\pm$ + nucleus) deeply inelastic scattering (DIS) data and Drell-Yan (DY) cross-section ratios $\sigma_{DY}^{A}/\sigma_{DY}^{A^\prime}$ for several nuclear targets. We study in detail the parametrizations and the atomic mass (A) dependence of the nuclear PDFs at this order. The present nuclear PDFs global analysis provides us a complete set of nuclear PDFs, $f_i^{(A,Z)}(x,Q^2)$, with a full functional dependence on $x$, A, Q$^2$. The uncertainties of the obtained nuclear modification factors for each parton flavour are estimated using the well-known Hessian method. The nuclear charm quark distributions are also added into the analysis. We compare the parametrization results with the available data and the results of other nuclear PDFs groups. We found our nuclear PDFs to be in reasonably good agreement with them. The estimates of errors provided by our global analysis are rather smaller than those of other groups. In general, a very good agreement is achieved. We also briefly review the recent heavy-ion collisions data including the first experimental data from the LHC proton+lead and lead+lead run which can be used in the global fits of nuclear PDFs. We highlight different aspects of the high luminosity Pb--Pb and p--Pb data which have been recorded by the CMS Collaboration.
[ { "created": "Tue, 5 Jan 2016 19:01:24 GMT", "version": "v1" }, { "created": "Wed, 27 Jan 2016 21:12:41 GMT", "version": "v2" } ]
2016-01-29
[ [ "Khanpour", "Hamzeh", "" ], [ "Tehrani", "S. Atashbar", "" ] ]
We perform a next-to-next-to-leading order (NNLO) analysis of nuclear parton distribution functions (nPDFs) using neutral current charged-lepton ($\ell ^\pm$ + nucleus) deeply inelastic scattering (DIS) data and Drell-Yan (DY) cross-section ratios $\sigma_{DY}^{A}/\sigma_{DY}^{A^\prime}$ for several nuclear targets. We study in detail the parametrizations and the atomic mass (A) dependence of the nuclear PDFs at this order. The present nuclear PDFs global analysis provides us a complete set of nuclear PDFs, $f_i^{(A,Z)}(x,Q^2)$, with a full functional dependence on $x$, A, Q$^2$. The uncertainties of the obtained nuclear modification factors for each parton flavour are estimated using the well-known Hessian method. The nuclear charm quark distributions are also added into the analysis. We compare the parametrization results with the available data and the results of other nuclear PDFs groups. We found our nuclear PDFs to be in reasonably good agreement with them. The estimates of errors provided by our global analysis are rather smaller than those of other groups. In general, a very good agreement is achieved. We also briefly review the recent heavy-ion collisions data including the first experimental data from the LHC proton+lead and lead+lead run which can be used in the global fits of nuclear PDFs. We highlight different aspects of the high luminosity Pb--Pb and p--Pb data which have been recorded by the CMS Collaboration.
2211.01040
Yannick Ulrich
P. Banerjee, A. M. Coutinho, T. Engel, A. Gurgone, A. Signer, Y. Ulrich
High-precision muon decay predictions for ALP searches
37 pages, 14 figures, published version
SciPost Phys. 15, 021 (2023)
10.21468/SciPostPhys.15.1.021
FR-PHENO-2022-10, IFIC/22-32, IPPP/22/75, PSI-PR-22-32, ZU-TH 50/22
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an improved theoretical prediction of the positron energy spectrum for the polarised Michel decay $\mu^+\to e^+ \nu_e\bar{\nu}_\mu$. In addition to the full next-to-next-to-leading order correction of order $\alpha^2$ in the electromagnetic coupling, we include logarithmically enhanced terms at even higher orders. Logarithms due to collinear emission are included at next-to-leading accuracy up to order $\alpha^4$. At the endpoint of the Michel spectrum, soft photon emission results in large logarithms that are resummed up to next-to-next-to-leading logarithmic accuracy. We apply our results in the context of the MEG II and Mu3e experiments to estimate the impact of the theory error on the branching ratio sensitivity for the lepton-flavour-violating decay $\mu^+\to e^+ X$ of a muon into an axion-like particle $X$.
[ { "created": "Wed, 2 Nov 2022 11:14:07 GMT", "version": "v1" }, { "created": "Sun, 23 Jul 2023 14:03:00 GMT", "version": "v2" } ]
2023-07-25
[ [ "Banerjee", "P.", "" ], [ "Coutinho", "A. M.", "" ], [ "Engel", "T.", "" ], [ "Gurgone", "A.", "" ], [ "Signer", "A.", "" ], [ "Ulrich", "Y.", "" ] ]
We present an improved theoretical prediction of the positron energy spectrum for the polarised Michel decay $\mu^+\to e^+ \nu_e\bar{\nu}_\mu$. In addition to the full next-to-next-to-leading order correction of order $\alpha^2$ in the electromagnetic coupling, we include logarithmically enhanced terms at even higher orders. Logarithms due to collinear emission are included at next-to-leading accuracy up to order $\alpha^4$. At the endpoint of the Michel spectrum, soft photon emission results in large logarithms that are resummed up to next-to-next-to-leading logarithmic accuracy. We apply our results in the context of the MEG II and Mu3e experiments to estimate the impact of the theory error on the branching ratio sensitivity for the lepton-flavour-violating decay $\mu^+\to e^+ X$ of a muon into an axion-like particle $X$.
2402.17534
Nahuel Barrios
Nahuel Barrios, Marcelo S. Guimaraes, Bruno W. Mintz, Let\'icia F. Palhares and Marcela Pel\'aez
Ghost-gluon vertex in the presence of the Gribov horizon: General kinematics
24 pages, 12 figures
Phys. Rev. D 109, 094039 (2024)
10.1103/PhysRevD.109.094039
null
hep-ph hep-lat hep-th
http://creativecommons.org/licenses/by/4.0/
Correlation functions are important probes for the behavior of quantum field theories. Already at tree-level, the Refined Gribov Zwanziger (RGZ) effective action for Yang-Mills theories provides a good approximation for the gluon propagator, as compared to that calculated by nonperturbative methods such as Lattice Field Theory and Dyson-Schwinger Equations. However, the study of higher correlation functions of the RGZ theory is still at its beginning. In this work we evaluate the ghost-antighost-gluon vertex function in Landau gauge at one-loop level, in $d=4$ space-time dimensions for the gauge groups SU(2) and SU(3). More precisely, we extend the analysis conducted in [1] for the soft-gluon limit to an arbitrary kinematic configuration. We introduce renormalization group effects by means of a toy model for the running coupling and investigate the impact of such a model in the ultraviolet tails of our results. We find that RGZ results match fairly closely those from lattice simulations, Schwinger-Dyson equations and the Curci-Ferrari model for three different kinematic configurations. This is compatible with RGZ being a feasible theory for the strong interaction in the infrared regime.
[ { "created": "Tue, 27 Feb 2024 14:21:32 GMT", "version": "v1" }, { "created": "Sat, 25 May 2024 22:41:14 GMT", "version": "v2" } ]
2024-05-28
[ [ "Barrios", "Nahuel", "" ], [ "Guimaraes", "Marcelo S.", "" ], [ "Mintz", "Bruno W.", "" ], [ "Palhares", "Letícia F.", "" ], [ "Peláez", "Marcela", "" ] ]
Correlation functions are important probes for the behavior of quantum field theories. Already at tree-level, the Refined Gribov Zwanziger (RGZ) effective action for Yang-Mills theories provides a good approximation for the gluon propagator, as compared to that calculated by nonperturbative methods such as Lattice Field Theory and Dyson-Schwinger Equations. However, the study of higher correlation functions of the RGZ theory is still at its beginning. In this work we evaluate the ghost-antighost-gluon vertex function in Landau gauge at one-loop level, in $d=4$ space-time dimensions for the gauge groups SU(2) and SU(3). More precisely, we extend the analysis conducted in [1] for the soft-gluon limit to an arbitrary kinematic configuration. We introduce renormalization group effects by means of a toy model for the running coupling and investigate the impact of such a model in the ultraviolet tails of our results. We find that RGZ results match fairly closely those from lattice simulations, Schwinger-Dyson equations and the Curci-Ferrari model for three different kinematic configurations. This is compatible with RGZ being a feasible theory for the strong interaction in the infrared regime.
hep-ph/9610333
Ahmed Ali
A. Ali (DESY, Hamburg)
Rare B Decays in the Standard Model
Latex2e, 25 pages, 4 figures (require epsf.sty, rotate). Invited talk. To be published in Proceedings of the 4th International Workshop 'Beauty-96', Roma, June 17 - 21, 1996
Nucl.Instrum.Meth. A384 (1996) 8-16
10.1016/S0168-9002(96)00908-4
null
hep-ph
null
We discuss the electromagnetic-penguin-dominated radiative B decays $B \to X_s + \gamma, ~B^{\pm (0)} \to K^{*\pm (0)} + \gamma$, and $B_s \to \phi + \gamma$ in the context of the standard model (SM) and their Cabibbo-Kobayashi-Maskawa (CKM)-suppressed counterparts, $B \to X_d + \gamma$, $B^\pm \to \rho^\pm + \gamma, ~B^{0} \to (\rho^{0}, \omega) + \gamma$, and $B_s \to K^{* 0} + \gamma$, using QCD sum rules for the exclusive decays. The importance of these decays in determining the parameters of the CKM matrix is emphasized. The semileptonic decays $B \to X_s \ell^+ \ell^-$ are also discussed in the context of the SM and their role in determining the Wilson coefficients of the effective theory is stressed. Comparison with the existing measurements are made and SM-based predictions for a large number of rare B decays are presented.
[ { "created": "Fri, 11 Oct 1996 15:44:33 GMT", "version": "v1" } ]
2009-10-28
[ [ "Ali", "A.", "", "DESY, Hamburg" ] ]
We discuss the electromagnetic-penguin-dominated radiative B decays $B \to X_s + \gamma, ~B^{\pm (0)} \to K^{*\pm (0)} + \gamma$, and $B_s \to \phi + \gamma$ in the context of the standard model (SM) and their Cabibbo-Kobayashi-Maskawa (CKM)-suppressed counterparts, $B \to X_d + \gamma$, $B^\pm \to \rho^\pm + \gamma, ~B^{0} \to (\rho^{0}, \omega) + \gamma$, and $B_s \to K^{* 0} + \gamma$, using QCD sum rules for the exclusive decays. The importance of these decays in determining the parameters of the CKM matrix is emphasized. The semileptonic decays $B \to X_s \ell^+ \ell^-$ are also discussed in the context of the SM and their role in determining the Wilson coefficients of the effective theory is stressed. Comparison with the existing measurements are made and SM-based predictions for a large number of rare B decays are presented.
hep-ph/0501162
Gilberto Tavares-Velasco
U. Cotti, M. Pineda, G. Tavares-Velasco
Lepton flavor violating Higgs boson decay H --> mu tau at muon colliders
10 pages, 6 figures
null
null
null
hep-ph
null
We consider an effective nondiagonal coupling $H\bar{\mu}\tau$ and present the analysis of the Higgs boson mediated lepton-flavor violating (LFV) reaction $\mu^-\mu^+ --> \mu \tau$. For a Higgs boson mass around 115 GeV and convenient values of the strength of the coupling $H\bar{\mu}\tau$, which are within the bounds obtained from the experimental limits on the LFV decays $\tau-->\eta\mu$ and $\tau-->\mu\gamma$, we found that there would be up to a few hundreds of $\mu \tau$ events per year at a muon collider running with an integrated luminosity of $1 fb^{-1}$. We paid special attention on the background for this LFV reaction, which arises from the standard model process $\mu^-\mu^+ --> \mu\tau\bar{\nu}_{\mu}\nu_{\tau}$, and discuss how it can be separated from the main signal.
[ { "created": "Tue, 18 Jan 2005 08:04:04 GMT", "version": "v1" } ]
2007-05-23
[ [ "Cotti", "U.", "" ], [ "Pineda", "M.", "" ], [ "Tavares-Velasco", "G.", "" ] ]
We consider an effective nondiagonal coupling $H\bar{\mu}\tau$ and present the analysis of the Higgs boson mediated lepton-flavor violating (LFV) reaction $\mu^-\mu^+ --> \mu \tau$. For a Higgs boson mass around 115 GeV and convenient values of the strength of the coupling $H\bar{\mu}\tau$, which are within the bounds obtained from the experimental limits on the LFV decays $\tau-->\eta\mu$ and $\tau-->\mu\gamma$, we found that there would be up to a few hundreds of $\mu \tau$ events per year at a muon collider running with an integrated luminosity of $1 fb^{-1}$. We paid special attention on the background for this LFV reaction, which arises from the standard model process $\mu^-\mu^+ --> \mu\tau\bar{\nu}_{\mu}\nu_{\tau}$, and discuss how it can be separated from the main signal.
hep-ph/0303044
Fabian Franke
H. Fraas, F. Franke, G. Moortgat-Pick, F. von der Pahlen, A. Wagner
Precision measurements of Higgs-chargino couplings in chargino pair production at a muon collider
14 pages, 5 figures
Eur.Phys.J.C29:587-595,2003
10.1140/epjc/s2003-01249-6
WUE-ITP-2003-003 IPPP-03-03 DCPT-03-06
hep-ph
null
We study chargino pair production on the heavy Higgs resonances at a muon collider in the MSSM. At $\sqrt{s} \approx 350$ GeV cross sections up to 2 pb are reached depending on the supersymmetric scenario and the beam energy spread. The resonances of the scalar and pseudoscalar Higgs bosons may be separated for $\tan\beta <8$. Our aim is to determine the ratio of the chargino couplings to the heavy scalar and pseudoscalar Higgs boson independently of the specific chargino decay characteristics. The precision of the measurement depends on the energy resolution of the muon collider and on the error in the measurement of the cross sections of the non-Higgs channels including an irreducible standard model background. With a high energy resolution the systematic error can be reduced to the order of a few percent.
[ { "created": "Wed, 5 Mar 2003 20:45:40 GMT", "version": "v1" }, { "created": "Wed, 9 Jul 2003 19:28:57 GMT", "version": "v2" } ]
2011-09-13
[ [ "Fraas", "H.", "" ], [ "Franke", "F.", "" ], [ "Moortgat-Pick", "G.", "" ], [ "von der Pahlen", "F.", "" ], [ "Wagner", "A.", "" ] ]
We study chargino pair production on the heavy Higgs resonances at a muon collider in the MSSM. At $\sqrt{s} \approx 350$ GeV cross sections up to 2 pb are reached depending on the supersymmetric scenario and the beam energy spread. The resonances of the scalar and pseudoscalar Higgs bosons may be separated for $\tan\beta <8$. Our aim is to determine the ratio of the chargino couplings to the heavy scalar and pseudoscalar Higgs boson independently of the specific chargino decay characteristics. The precision of the measurement depends on the energy resolution of the muon collider and on the error in the measurement of the cross sections of the non-Higgs channels including an irreducible standard model background. With a high energy resolution the systematic error can be reduced to the order of a few percent.
2311.12158
Gabriele Levati
Luca Di Luzio, Gabriele Levati and Paride Paradisi
The Chiral Lagrangian of CP-Violating Axion-Like Particles
Matches published version. 28 pages, 1 figure, 3 tables. FeynRules models for both the 2-flavours and the 3-flavours case are provided in the ancillary files
J. High Energ. Phys. 2024, 20 (2024)
10.1007/JHEP02(2024)020
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We discuss the construction of the most general CP-violating chiral Lagrangian for an axion-like particle (ALP). Starting with an effective Lagrangian containing light quarks and gluons, we provide its matching onto a chiral effective Lagrangian at $\mathcal{O}(p^2)$ described in terms of mesons and baryons, identifying the correspondence between the Jarlskog invariants of the two theories. After deriving the ALP interactions with mesons and baryons, we analyse a few relevant phenomenological implications such as the permanent electric dipole moments of nucleons and the CP-violating ALP and kaon decays.This work provides the necessary tools for further phenomenological analyses connecting low-energy observables with the couplings of the underlying ultraviolet complete theory.
[ { "created": "Mon, 20 Nov 2023 20:24:11 GMT", "version": "v1" }, { "created": "Sat, 3 Feb 2024 11:19:16 GMT", "version": "v2" } ]
2024-02-06
[ [ "Di Luzio", "Luca", "" ], [ "Levati", "Gabriele", "" ], [ "Paradisi", "Paride", "" ] ]
We discuss the construction of the most general CP-violating chiral Lagrangian for an axion-like particle (ALP). Starting with an effective Lagrangian containing light quarks and gluons, we provide its matching onto a chiral effective Lagrangian at $\mathcal{O}(p^2)$ described in terms of mesons and baryons, identifying the correspondence between the Jarlskog invariants of the two theories. After deriving the ALP interactions with mesons and baryons, we analyse a few relevant phenomenological implications such as the permanent electric dipole moments of nucleons and the CP-violating ALP and kaon decays.This work provides the necessary tools for further phenomenological analyses connecting low-energy observables with the couplings of the underlying ultraviolet complete theory.
1702.04440
Duojie Jia
Ming-Zhu Liu, Duo-Jie Jia and Dian-Yong Chen
Possible hadronic molecular states composed of $S$-wave heavy-light mesons
11 pages, 1 eps figure. Accepted in "Chin. Phys. C"
Chins. Phys. C, Vol. 41, No. 5 (2017) 053105
10.1088/1674-1137/41/5/053105
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We perform a systematical study of possible molecular states composed of the $S$ wave heavy light mesons, where the $S-D$ mixing and {$\eta-\eta^{\prime}$ mixing} are explicitly included. Our calculation indicates that the observed $X(3872)$ could be a loosely shallow molecular state composed of $D\bar{D}^\ast +h.c$, while neither $Z_c(3900)/Z_c(4020)$ nor $Z_b(10610)/Z_b(10650)$ is supported to be a molecule. Some observed possible molecular states are predicted, which could be searched for by further experimental measurements.
[ { "created": "Wed, 15 Feb 2017 01:52:18 GMT", "version": "v1" } ]
2024-06-14
[ [ "Liu", "Ming-Zhu", "" ], [ "Jia", "Duo-Jie", "" ], [ "Chen", "Dian-Yong", "" ] ]
We perform a systematical study of possible molecular states composed of the $S$ wave heavy light mesons, where the $S-D$ mixing and {$\eta-\eta^{\prime}$ mixing} are explicitly included. Our calculation indicates that the observed $X(3872)$ could be a loosely shallow molecular state composed of $D\bar{D}^\ast +h.c$, while neither $Z_c(3900)/Z_c(4020)$ nor $Z_b(10610)/Z_b(10650)$ is supported to be a molecule. Some observed possible molecular states are predicted, which could be searched for by further experimental measurements.
hep-ph/0411056
Stanley J. Brodsky
S. J. Brodsky (SLAC)
New Results in Light-Front Phenomenology
Presented at LightCone 2004, Amsterdam, The Netherlands, 16-20 August 2004
Few Body Syst.36:35-52,2005
10.1007/s00601-004-0077-8
SLAC-PUB-10812
hep-ph
null
The light-front quantization of gauge theories such as QCD in light-cone gauge provides a frame-independent wavefunction representation of relativistic bound states, simple forms for current matrix elements, explicit unitarity, and a trivial vacuum. The freedom to choose the light-like quantization four-vector provides an explicitly covariant formulation of light-front quantization and can be used to determine the analytic structure of light-front wave functions and to define a kinematical definition of angular momentum. The AdS/CFT correspondence of large $N_C$ supergravity theory in higher-dimensional anti-de Sitter space with supersymmetric QCD in 4-dimensional space-time has interesting implications for hadron phenomenology in the conformal limit, including an all-orders demonstration of counting rules for exclusive processes. String/gauge duality also predicts the QCD power-law behavior of light-front Fock-state hadronic wavefunctions with arbitrary orbital angular momentum at high momentum transfer. The form of these near-conformal wavefunctions can be used as an initial ansatz for a variational treatment of the light-front QCD Hamiltonian. I also briefly review recent analyses which shows that some leading-twist phenomena such as the diffractive component of deep inelastic scattering, single-spin asymmetries, nuclear shadowing and antishadowing cannot be computed from the LFWFs of hadrons in isolation.
[ { "created": "Thu, 4 Nov 2004 04:50:45 GMT", "version": "v1" } ]
2009-09-11
[ [ "Brodsky", "S. J.", "", "SLAC" ] ]
The light-front quantization of gauge theories such as QCD in light-cone gauge provides a frame-independent wavefunction representation of relativistic bound states, simple forms for current matrix elements, explicit unitarity, and a trivial vacuum. The freedom to choose the light-like quantization four-vector provides an explicitly covariant formulation of light-front quantization and can be used to determine the analytic structure of light-front wave functions and to define a kinematical definition of angular momentum. The AdS/CFT correspondence of large $N_C$ supergravity theory in higher-dimensional anti-de Sitter space with supersymmetric QCD in 4-dimensional space-time has interesting implications for hadron phenomenology in the conformal limit, including an all-orders demonstration of counting rules for exclusive processes. String/gauge duality also predicts the QCD power-law behavior of light-front Fock-state hadronic wavefunctions with arbitrary orbital angular momentum at high momentum transfer. The form of these near-conformal wavefunctions can be used as an initial ansatz for a variational treatment of the light-front QCD Hamiltonian. I also briefly review recent analyses which shows that some leading-twist phenomena such as the diffractive component of deep inelastic scattering, single-spin asymmetries, nuclear shadowing and antishadowing cannot be computed from the LFWFs of hadrons in isolation.
2309.02715
Qing Chen
Qing Chen, Gui-Jun Ding, Richard J. Hill
General Heavy WIMP Nucleon Elastic Scattering
22 pages, 8 figures
null
null
USTC-ICTS/PCFT-23-26; FERMILAB-PUB-23-423-T
hep-ph astro-ph.CO hep-ex
http://creativecommons.org/licenses/by/4.0/
Heavy WIMP (weakly-interacting-massive-particle) effective field theory is used to compute the WIMP-nucleon scattering rate for general heavy electroweak multiplets through order $m_W/M$, where $m_W$ and $M$ denote the electroweak and WIMP mass scales. The lightest neutral component of such an electroweak multiplet is a candidate dark matter particle, either elementary or composite. Existing computations for certain representations of electroweak $\mathrm{SU(2)}_W\times \mathrm{U(1)}_Y$ reveal a cancellation of amplitudes from different effective operators at leading and subleading orders in $1/M$, yielding small cross sections that are below current dark matter direct detection experimental sensitivities. We extend those computations and consider all low-spin (spin-0, spin-1/2, spin-1, spin-3/2) heavy electroweak multiplets with arbitrary $\mathrm{SU(2)}_W\times \mathrm{U(1)}_Y$ representations and provide benchmark cross section results for dark matter direct detection experiments. For most self-conjugate TeV WIMPs with isospin $\le 3$, the cross sections are below current experimental limits but within reach of next-generation experiments. An exception is the case of pure electroweak doublet, where WIMPs are hidden below the neutrino floor.
[ { "created": "Wed, 6 Sep 2023 04:58:06 GMT", "version": "v1" } ]
2023-09-07
[ [ "Chen", "Qing", "" ], [ "Ding", "Gui-Jun", "" ], [ "Hill", "Richard J.", "" ] ]
Heavy WIMP (weakly-interacting-massive-particle) effective field theory is used to compute the WIMP-nucleon scattering rate for general heavy electroweak multiplets through order $m_W/M$, where $m_W$ and $M$ denote the electroweak and WIMP mass scales. The lightest neutral component of such an electroweak multiplet is a candidate dark matter particle, either elementary or composite. Existing computations for certain representations of electroweak $\mathrm{SU(2)}_W\times \mathrm{U(1)}_Y$ reveal a cancellation of amplitudes from different effective operators at leading and subleading orders in $1/M$, yielding small cross sections that are below current dark matter direct detection experimental sensitivities. We extend those computations and consider all low-spin (spin-0, spin-1/2, spin-1, spin-3/2) heavy electroweak multiplets with arbitrary $\mathrm{SU(2)}_W\times \mathrm{U(1)}_Y$ representations and provide benchmark cross section results for dark matter direct detection experiments. For most self-conjugate TeV WIMPs with isospin $\le 3$, the cross sections are below current experimental limits but within reach of next-generation experiments. An exception is the case of pure electroweak doublet, where WIMPs are hidden below the neutrino floor.
1907.08662
Wim Cosyn
W. Cosyn, B. Pire, L. Szymanowski
Probing quark transversity GPDs in diffractive photo- and electroproduction on the deuteron
Proceedings of DIS2019, 6 pages, 3 figures
null
null
CPHT-PC049.072019
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Transversity generalized parton distributions (GPDs) can be probed in diffractive electro- and photoproduction of two vector mesons on a hadron in kinematics where the two vector mesons are separated by a large rapidity gap. We report on calculations for this process in the case of coherent $\rho^0-\omega$ meson production on a deuteron target. Our cross section results show that an electron-ion collider with deuteron beams and forward detectors could probe deuteron transversity GPDs.
[ { "created": "Fri, 19 Jul 2019 19:47:13 GMT", "version": "v1" } ]
2019-07-23
[ [ "Cosyn", "W.", "" ], [ "Pire", "B.", "" ], [ "Szymanowski", "L.", "" ] ]
Transversity generalized parton distributions (GPDs) can be probed in diffractive electro- and photoproduction of two vector mesons on a hadron in kinematics where the two vector mesons are separated by a large rapidity gap. We report on calculations for this process in the case of coherent $\rho^0-\omega$ meson production on a deuteron target. Our cross section results show that an electron-ion collider with deuteron beams and forward detectors could probe deuteron transversity GPDs.
hep-ph/0612115
Masashi Wakamatsu
M. Wakamatsu
Generalized Form Factors, Generalized Parton Distributions and Spin Contents of the Nucleon
4 pages, 2 figures. Talk presented at SPIN2006, October 2-7, 2006, Kyoto, Japan
AIP Conf.Proc.915:630-633,2007
10.1063/1.2750859
OU-HET-571
hep-ph
null
A model independent prediction is given for the nucleon spin contents, based only upon a reasonable theoretical postulate on the isosinglet anomalous gravitomagnetic moment of the nucleon.
[ { "created": "Mon, 11 Dec 2006 01:52:40 GMT", "version": "v1" } ]
2011-04-11
[ [ "Wakamatsu", "M.", "" ] ]
A model independent prediction is given for the nucleon spin contents, based only upon a reasonable theoretical postulate on the isosinglet anomalous gravitomagnetic moment of the nucleon.
hep-ph/0312083
Atsushi Hosaka
A.W. Thomas, K. Hicks and A. Hosaka
A Method to Unambiguously Determine the Parity of the Theta+ Pentaquark
3 pages
Prog.Theor.Phys.111:291-293,2004
10.1143/PTP.111.291
null
hep-ph
null
With the recent discovery of the $\Theta(1540)$ pentaquark, the question of its parity is paramount since this will constrain the correct description of its internal structure. We show that the measurement of the spin singlet and triplet cross sections for the reaction $\vec{p}\vec{p} \to \Sigma^+ \Theta^+$ will unambiguously determine the parity of the $\Theta^+$.
[ { "created": "Fri, 5 Dec 2003 13:29:30 GMT", "version": "v1" }, { "created": "Sun, 7 Dec 2003 06:28:18 GMT", "version": "v2" } ]
2010-02-17
[ [ "Thomas", "A. W.", "" ], [ "Hicks", "K.", "" ], [ "Hosaka", "A.", "" ] ]
With the recent discovery of the $\Theta(1540)$ pentaquark, the question of its parity is paramount since this will constrain the correct description of its internal structure. We show that the measurement of the spin singlet and triplet cross sections for the reaction $\vec{p}\vec{p} \to \Sigma^+ \Theta^+$ will unambiguously determine the parity of the $\Theta^+$.
1602.01322
C. J. A. P. Martins
C. J. A. P. Martins, I. Yu. Rybak, A. Avgoustidis, E. P. S. Shellard
Extending the velocity-dependent one-scale model for domain walls
10 pages, 7 figures; Phys. Rev. D (in press); v2: minor changes, matches published version
Phys. Rev. D 93, 043534 (2016)
10.1103/PhysRevD.93.043534
null
hep-ph astro-ph.CO gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We report on an extensive study of the evolution of domain wall networks in Friedmann-Lema\^{\i}tre-Robertson-Walker universes by means of the largest currently available field-theory simulations. These simulations were done in $4096^3$ boxes and for a range of different fixed expansion rates, as well as for the transition between the radiation and matter eras. A detailed comparison with the velocity-dependent one-scale (VOS) model shows that this cannot accurately reproduce the results of the entire range of simulated regimes if one assumes that the phenomenological energy loss and momentum parameters are constants. We therefore discuss how a more accurate modeling of these parameters can be done, specifically by introducing an additional mechanism of energy loss (scalar radiation, which is particularly relevant for regimes with relatively little damping) and a modified momentum parameter which is a function of velocity (in analogy to what was previously done for cosmic strings). We finally show that this extended model, appropriately calibrated, provides an accurate fit to our simulations.
[ { "created": "Wed, 3 Feb 2016 14:48:34 GMT", "version": "v1" }, { "created": "Wed, 17 Feb 2016 18:32:31 GMT", "version": "v2" } ]
2016-03-09
[ [ "Martins", "C. J. A. P.", "" ], [ "Rybak", "I. Yu.", "" ], [ "Avgoustidis", "A.", "" ], [ "Shellard", "E. P. S.", "" ] ]
We report on an extensive study of the evolution of domain wall networks in Friedmann-Lema\^{\i}tre-Robertson-Walker universes by means of the largest currently available field-theory simulations. These simulations were done in $4096^3$ boxes and for a range of different fixed expansion rates, as well as for the transition between the radiation and matter eras. A detailed comparison with the velocity-dependent one-scale (VOS) model shows that this cannot accurately reproduce the results of the entire range of simulated regimes if one assumes that the phenomenological energy loss and momentum parameters are constants. We therefore discuss how a more accurate modeling of these parameters can be done, specifically by introducing an additional mechanism of energy loss (scalar radiation, which is particularly relevant for regimes with relatively little damping) and a modified momentum parameter which is a function of velocity (in analogy to what was previously done for cosmic strings). We finally show that this extended model, appropriately calibrated, provides an accurate fit to our simulations.
hep-ph/0011275
Saebyok Bae
Saebyok Bae, Hong Seok Lee
Bounds on the Mass and Coupling Constant of Radion in the Randall-Sundrum Theory
11 pages, 3 figures, a minor change, to appear in Phys. Lett. B
Phys.Lett. B506 (2001) 147-154
10.1016/S0370-2693(01)00415-4
null
hep-ph
null
Assuming the Goldberger-Wise mechanism, we investigated the effective potential at the one-loop level in the Randall-Sundrum theory. We found the lower and upper bounds of the radion mass m_\phi and the radion-SM coupling constant, 0.8 GeV \lesssim m_\phi \lesssim 260 GeV and 1400 GeV \lesssim \Lambda_\phi \lesssim 1500 GeV for the one-loop level potential. These bounds were determined from two constraints of warp factor = O(M_W/M_{Pl}) and Higgs vev \simeq 246 GeV, which can produce strong bounds of m_\phi and \Lambda_\phi. It is phenomenologically important that the one-loop allowed upper bound of the radion mass is about five times larger than the tree-level one, but the radion is still lighter than the Kaluza-Klein modes.
[ { "created": "Wed, 22 Nov 2000 07:06:46 GMT", "version": "v1" }, { "created": "Wed, 3 Jan 2001 06:26:25 GMT", "version": "v2" }, { "created": "Tue, 27 Mar 2001 13:10:58 GMT", "version": "v3" }, { "created": "Tue, 17 Apr 2001 08:20:31 GMT", "version": "v4" } ]
2009-10-31
[ [ "Bae", "Saebyok", "" ], [ "Lee", "Hong Seok", "" ] ]
Assuming the Goldberger-Wise mechanism, we investigated the effective potential at the one-loop level in the Randall-Sundrum theory. We found the lower and upper bounds of the radion mass m_\phi and the radion-SM coupling constant, 0.8 GeV \lesssim m_\phi \lesssim 260 GeV and 1400 GeV \lesssim \Lambda_\phi \lesssim 1500 GeV for the one-loop level potential. These bounds were determined from two constraints of warp factor = O(M_W/M_{Pl}) and Higgs vev \simeq 246 GeV, which can produce strong bounds of m_\phi and \Lambda_\phi. It is phenomenologically important that the one-loop allowed upper bound of the radion mass is about five times larger than the tree-level one, but the radion is still lighter than the Kaluza-Klein modes.
1208.3562
Joseph Conlon
Michele Cicoli, Joseph P. Conlon, Fernando Quevedo
Dark Radiation in LARGE Volume Models
6 pages; v2. refs updated
null
10.1103/PhysRevD.87.043520
DAMTP-2012-59
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider reheating driven by volume modulus decays in the LARGE Volume Scenario. Such reheating always generates non-zero dark radiation through the decays to the axion partner, while the only competitive visible sector decays are Higgs pairs via the Giudice-Masiero term. In the framework of sequestered models where the cosmological moduli problem is absent, the simplest model with a shift-symmetric Higgs sector generates 1.56 < N_{eff} - N_{eff,SM} < 1.74. For more general cases, the known experimental bounds on N_{eff} strongly constrain the parameters and matter content of the models.
[ { "created": "Fri, 17 Aug 2012 10:00:00 GMT", "version": "v1" }, { "created": "Fri, 21 Sep 2012 16:10:38 GMT", "version": "v2" } ]
2013-03-14
[ [ "Cicoli", "Michele", "" ], [ "Conlon", "Joseph P.", "" ], [ "Quevedo", "Fernando", "" ] ]
We consider reheating driven by volume modulus decays in the LARGE Volume Scenario. Such reheating always generates non-zero dark radiation through the decays to the axion partner, while the only competitive visible sector decays are Higgs pairs via the Giudice-Masiero term. In the framework of sequestered models where the cosmological moduli problem is absent, the simplest model with a shift-symmetric Higgs sector generates 1.56 < N_{eff} - N_{eff,SM} < 1.74. For more general cases, the known experimental bounds on N_{eff} strongly constrain the parameters and matter content of the models.