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1710.11466
Mariola Klusek-Gawenda
Mariola Klusek-Gawenda and Antoni Szczurek
New theoretical results in ultrarelativistic ultraperipheral lead-lead collisions
6 pages, 2 figures, talk was given by M. Klusek-Gawenda at the 17th conference on Elastic and Diffractive scattering, EDS Blois 2017, Prague, Czech Republic, June 26-30, 2017
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study dilepton, proton-antiproton and diphoton production in ultraperipheral lead-lead collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 and 5.5 TeV. The nuclear calculations are based on equivalent photon approximation in the impact parameter space. For correct description of the $\gamma\gamma \to p\bar{p} $ Belle data we include the proton-exchange, the $f_2(1270)$ and $f_2(1950)$ s-channel exchanges, as well as the handbag mechanism. For four muon production, we take into account electromagnetic (two-photon) double-scattering production and direct $\gamma\gamma$ production of four muons in one scattering. The cross sections for elementary $\gamma\gamma \to \gamma\gamma$ subprocess are calculated including three different mechanisms: box diagrams with leptons and quarks in the loops, a VDM-Regge contribution with virtual intermediate hadronic excitations of the photons and the two-gluon exchange contribution. We find that the cross section for elastic $\gamma\gamma$ scattering could be measured in the lead-lead collisions for the diphoton invariant mass up to $W_{\gamma\gamma} \approx$ 15 - 20 GeV. Our Standard Model predictions are compared with a recent ATLAS experimental result. We discuss results for PbPb$\to$PbPb$\mu^+\mu^-\mu^+\mu^-$, PbPb$\to$PbPb$e^+e^-e^+e^-$, PbPb$\to$PbPb$p\bar{p}$ and PbPb$\to$PbPb$\gamma\gamma$ reactions at LHC energy.
[ { "created": "Tue, 31 Oct 2017 13:42:06 GMT", "version": "v1" } ]
2017-11-01
[ [ "Klusek-Gawenda", "Mariola", "" ], [ "Szczurek", "Antoni", "" ] ]
We study dilepton, proton-antiproton and diphoton production in ultraperipheral lead-lead collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 and 5.5 TeV. The nuclear calculations are based on equivalent photon approximation in the impact parameter space. For correct description of the $\gamma\gamma \to p\bar{p} $ Belle data we include the proton-exchange, the $f_2(1270)$ and $f_2(1950)$ s-channel exchanges, as well as the handbag mechanism. For four muon production, we take into account electromagnetic (two-photon) double-scattering production and direct $\gamma\gamma$ production of four muons in one scattering. The cross sections for elementary $\gamma\gamma \to \gamma\gamma$ subprocess are calculated including three different mechanisms: box diagrams with leptons and quarks in the loops, a VDM-Regge contribution with virtual intermediate hadronic excitations of the photons and the two-gluon exchange contribution. We find that the cross section for elastic $\gamma\gamma$ scattering could be measured in the lead-lead collisions for the diphoton invariant mass up to $W_{\gamma\gamma} \approx$ 15 - 20 GeV. Our Standard Model predictions are compared with a recent ATLAS experimental result. We discuss results for PbPb$\to$PbPb$\mu^+\mu^-\mu^+\mu^-$, PbPb$\to$PbPb$e^+e^-e^+e^-$, PbPb$\to$PbPb$p\bar{p}$ and PbPb$\to$PbPb$\gamma\gamma$ reactions at LHC energy.
2201.03390
Sven Heinemeyer
Manimala Chakraborti, Sven Heinemeyer, Ipsita Saha
SUSY Dark Matter Direct Detection Prospects based on $(g-2)_\mu$
7 pages, 1 figure, invited talk given at the 20th Lomonosov conference, August 2021; based on arXiv:2103.13403, arXiv:2112.01389
null
null
IFT-UAM/CSIC-22-001
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
An electroweak (EW) sector of the Minimal Supersymmetric Standard Model (MSSM) with masses of a few hundred GeV can account for variety of experimental data, assuming the lightest neutralino to be the lightest supersymmetric (SUSY) particle: the non-observation at the LHC searches owing to their small production cross sections, the results for the (upper limit of the) Dark Matter (DM) relic abundance and the DM Direct Detection (DD) limits. Such a light EW sector can in particular explain the reinforced $4.2\,\sigma$ discrepancy between the experimental result for $(g-2)_\mu$, and its Standard Model (SM) prediction. Using the improved limits on $(g-2)_\mu$, we review the predictions for the future prospects of the DD experiments. This analysis is performed for several different realizations of DM in the MSSM: bino, bino/wino, wino and higgsino DM. We find that higgsino, wino and one type of bino scenario can be covered by future DD experiments. Mixed bino/wino and another type of bino DM can reach DD cross sections below the neutrino floor. In these cases future collider experiments must cover the remaining parameter space.
[ { "created": "Mon, 10 Jan 2022 15:14:38 GMT", "version": "v1" } ]
2022-01-11
[ [ "Chakraborti", "Manimala", "" ], [ "Heinemeyer", "Sven", "" ], [ "Saha", "Ipsita", "" ] ]
An electroweak (EW) sector of the Minimal Supersymmetric Standard Model (MSSM) with masses of a few hundred GeV can account for variety of experimental data, assuming the lightest neutralino to be the lightest supersymmetric (SUSY) particle: the non-observation at the LHC searches owing to their small production cross sections, the results for the (upper limit of the) Dark Matter (DM) relic abundance and the DM Direct Detection (DD) limits. Such a light EW sector can in particular explain the reinforced $4.2\,\sigma$ discrepancy between the experimental result for $(g-2)_\mu$, and its Standard Model (SM) prediction. Using the improved limits on $(g-2)_\mu$, we review the predictions for the future prospects of the DD experiments. This analysis is performed for several different realizations of DM in the MSSM: bino, bino/wino, wino and higgsino DM. We find that higgsino, wino and one type of bino scenario can be covered by future DD experiments. Mixed bino/wino and another type of bino DM can reach DD cross sections below the neutrino floor. In these cases future collider experiments must cover the remaining parameter space.
hep-ph/0511219
John F. Donoghue
John F. Donoghue, Koushik Dutta and Andreas Ross
Quark and lepton masses and mixing in the landscape
32 pages, 17 figures, some references added
Phys.Rev.D73:113002,2006
10.1103/PhysRevD.73.113002
null
hep-ph hep-th
null
Even if quark and lepton masses are not uniquely predicted by the fundamental theory, as may be the case in the string theory landscape, nevertheless their pattern may reveal features of the underlying theory. We use statistical techniques to show that the observed masses appear to be representative of a scale invariant distribution, rho(m) ~ 1/m. If we extend this distribution to include all the Yukawa couplings, we show that the resulting CKM matrix elements typically show a hierarchical pattern similar to observations. The Jarlskog invariant measuring the amount of CP violation is also well reproduced in magnitude. We also apply this framework to neutrinos using the seesaw mechanism. The neutrino results are ambiguous, with the observed pattern being statistically allowed even though the framework does not provide a natural explanation for the observed two large mixing angles. Our framework highly favors a normal hierarchy of neutrino masses. We also are able to make statistical predictions in the neutrino sector when we specialize to situations consistent with the known mass differences and two large mixing angles. Within our framework, we show that with 95% confidence the presently unmeasured MNS mixing angle sin theta_{13} is larger than 0.04 and typically of order 0.1. The leptonic Jarlskog invariant is found to be typically of order 10^{-2} and the magnitude of the effective Majorana mass m_{ee} is typically of order 0.001 eV.
[ { "created": "Thu, 17 Nov 2005 21:19:18 GMT", "version": "v1" }, { "created": "Fri, 27 Jan 2006 19:37:59 GMT", "version": "v2" } ]
2014-11-18
[ [ "Donoghue", "John F.", "" ], [ "Dutta", "Koushik", "" ], [ "Ross", "Andreas", "" ] ]
Even if quark and lepton masses are not uniquely predicted by the fundamental theory, as may be the case in the string theory landscape, nevertheless their pattern may reveal features of the underlying theory. We use statistical techniques to show that the observed masses appear to be representative of a scale invariant distribution, rho(m) ~ 1/m. If we extend this distribution to include all the Yukawa couplings, we show that the resulting CKM matrix elements typically show a hierarchical pattern similar to observations. The Jarlskog invariant measuring the amount of CP violation is also well reproduced in magnitude. We also apply this framework to neutrinos using the seesaw mechanism. The neutrino results are ambiguous, with the observed pattern being statistically allowed even though the framework does not provide a natural explanation for the observed two large mixing angles. Our framework highly favors a normal hierarchy of neutrino masses. We also are able to make statistical predictions in the neutrino sector when we specialize to situations consistent with the known mass differences and two large mixing angles. Within our framework, we show that with 95% confidence the presently unmeasured MNS mixing angle sin theta_{13} is larger than 0.04 and typically of order 0.1. The leptonic Jarlskog invariant is found to be typically of order 10^{-2} and the magnitude of the effective Majorana mass m_{ee} is typically of order 0.001 eV.
0706.3496
Makiko Nio
T. Aoyama, M. Hayakawa, T. Kinoshita, and M. Nio
Revised value of the eighth-order electron g-2
4 pages, 1 figure, typo is corrected
Phys.Rev.Lett.99:110406,2007
10.1103/PhysRevLett.99.110406
null
hep-ph
null
The contribution to the eighth-order anomalous magnetic moment (g-2) of the electron from a set of diagrams without closed lepton loops is recalculated using a new FORTRAN code generated by an automatic code generator. Comparing the contributions of individual diagrams of old and new calculations, we found an inconsistency in the old treatment of infrared subtraction terms in two diagrams. Correcting this error leads to the revised value -1.9144 (35) (alpha/pi)^4 for the eighth-order term. This theoretical change induces the shift of the inverse of the fine structure constant by -6.41180(73)x10^{-7}.
[ { "created": "Sun, 24 Jun 2007 08:11:04 GMT", "version": "v1" }, { "created": "Tue, 26 Jun 2007 01:50:47 GMT", "version": "v2" } ]
2008-11-26
[ [ "Aoyama", "T.", "" ], [ "Hayakawa", "M.", "" ], [ "Kinoshita", "T.", "" ], [ "Nio", "M.", "" ] ]
The contribution to the eighth-order anomalous magnetic moment (g-2) of the electron from a set of diagrams without closed lepton loops is recalculated using a new FORTRAN code generated by an automatic code generator. Comparing the contributions of individual diagrams of old and new calculations, we found an inconsistency in the old treatment of infrared subtraction terms in two diagrams. Correcting this error leads to the revised value -1.9144 (35) (alpha/pi)^4 for the eighth-order term. This theoretical change induces the shift of the inverse of the fine structure constant by -6.41180(73)x10^{-7}.
1507.08297
Chandan Hati
Mansi Dhuria, Chandan Hati and Utpal Sarkar
Explaining the CMS excesses, baryogenesis and neutrino masses in $E_{6}$ motivated $U(1)_{N}$ model
10 pages, 6 figures
Phys. Rev. D 93, 015001 (2016)
10.1103/PhysRevD.93.015001
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the superstring inspired $E_{6}$ model motivated $U(1)_{N}$ extension of the supersymmetric standard model to explore the possibility of explaining the recent excess CMS events and the baryon asymmetry of the universe in eight possible variants of the model. In light of the hints from short-baseline neutrino experiments at the existence of one or more light sterile neutrinos, we also study the neutrino mass matrices dictated by the field assignments and the discrete symmetries in these variants. We find that all the variants can explain the excess CMS events via the exotic slepton decay, while for a standard choice of the discrete symmetry four of the variants have the feature of allowing high scale baryogenesis (leptogenesis). For one other variant three body decay induced soft baryogenesis mechanism is possible which can induce baryon number violating neutron-antineutron oscillation. We also point out a new discrete symmetry which has the feature of ensuring proton stability and forbidding tree level flavor changing neutral current processes while allowing for the possibility of high scale leptogenesis for two of the variants. On the other hand, neutrino mass matrix of the $U(1)_{N}$ model variants naturally accommodates three active and two sterile neutrinos which acquire masses through their mixing with extra neutral fermions giving rise to interesting textures for neutrino masses.
[ { "created": "Wed, 29 Jul 2015 20:19:10 GMT", "version": "v1" } ]
2016-01-13
[ [ "Dhuria", "Mansi", "" ], [ "Hati", "Chandan", "" ], [ "Sarkar", "Utpal", "" ] ]
We study the superstring inspired $E_{6}$ model motivated $U(1)_{N}$ extension of the supersymmetric standard model to explore the possibility of explaining the recent excess CMS events and the baryon asymmetry of the universe in eight possible variants of the model. In light of the hints from short-baseline neutrino experiments at the existence of one or more light sterile neutrinos, we also study the neutrino mass matrices dictated by the field assignments and the discrete symmetries in these variants. We find that all the variants can explain the excess CMS events via the exotic slepton decay, while for a standard choice of the discrete symmetry four of the variants have the feature of allowing high scale baryogenesis (leptogenesis). For one other variant three body decay induced soft baryogenesis mechanism is possible which can induce baryon number violating neutron-antineutron oscillation. We also point out a new discrete symmetry which has the feature of ensuring proton stability and forbidding tree level flavor changing neutral current processes while allowing for the possibility of high scale leptogenesis for two of the variants. On the other hand, neutrino mass matrix of the $U(1)_{N}$ model variants naturally accommodates three active and two sterile neutrinos which acquire masses through their mixing with extra neutral fermions giving rise to interesting textures for neutrino masses.
2104.03947
Bhubanjyoti Bhattacharya
Bhubanjyoti Bhattacharya, Alakabha Datta, Danny Marfatia, Soumitra Nandi, and John Waite
Axion-like particles resolve the $B \to \pi K$ and g-2 anomalies
6 pages, 3 tables. Version to appear as a Letter in PRD
Phys. Rev. D 104, L051701 (2021)
10.1103/PhysRevD.104.L051701
UMISS-HEP-2021-02
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We offer a new solution to an old puzzle in the penguin-dominated $B\to\pi K$ decays. The puzzle is the inconsistency among the measurements of the branching ratios and CP asymmetries of the four $B\to\pi K$ decays: $B^+ \to \pi^+ K^0$, $B^+\to \pi^0 K^+$, $B_d^0\to\pi^- K^+$, $B_d^0\to\pi^0 K^0$. We solve the $B\to\pi K$ puzzle by considering the effect of an axion-like particle (ALP) that mixes with the $\pi^0$ and has mass close to the $\pi^0$ mass. We show that the ALP can also explain the anomalies in the electron and muon anomalous magnetic moments.
[ { "created": "Thu, 8 Apr 2021 17:43:56 GMT", "version": "v1" }, { "created": "Mon, 26 Apr 2021 02:01:43 GMT", "version": "v2" }, { "created": "Thu, 12 Aug 2021 16:53:18 GMT", "version": "v3" } ]
2023-08-17
[ [ "Bhattacharya", "Bhubanjyoti", "" ], [ "Datta", "Alakabha", "" ], [ "Marfatia", "Danny", "" ], [ "Nandi", "Soumitra", "" ], [ "Waite", "John", "" ] ]
We offer a new solution to an old puzzle in the penguin-dominated $B\to\pi K$ decays. The puzzle is the inconsistency among the measurements of the branching ratios and CP asymmetries of the four $B\to\pi K$ decays: $B^+ \to \pi^+ K^0$, $B^+\to \pi^0 K^+$, $B_d^0\to\pi^- K^+$, $B_d^0\to\pi^0 K^0$. We solve the $B\to\pi K$ puzzle by considering the effect of an axion-like particle (ALP) that mixes with the $\pi^0$ and has mass close to the $\pi^0$ mass. We show that the ALP can also explain the anomalies in the electron and muon anomalous magnetic moments.
1011.3450
Olaf Kittel
Olaf Kittel
How light can the lightest neutralino be?
6 pages, 3 figures, to appear in the proceedings of the 16th International Symposium on Particles, Strings and Cosmology (PASCOS2010), Valencia (Spain), July 19th - 23rd, 2010
J.Phys.Conf.Ser.259:012058,2010
10.1088/1742-6596/259/1/012058
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this talk we summarize previous work on mass bounds of a light neutralino in the Minimal Supersymmetric Standard Model. We show that without the GUT relation between the gaugino mass parameters M_1 and M_2, the mass of the lightest neutralino is essentially unconstrained by collider bounds and precision observables. We conclude by considering also the astrophysics and cosmology of a light neutralino.
[ { "created": "Mon, 15 Nov 2010 17:06:02 GMT", "version": "v1" } ]
2011-01-27
[ [ "Kittel", "Olaf", "" ] ]
In this talk we summarize previous work on mass bounds of a light neutralino in the Minimal Supersymmetric Standard Model. We show that without the GUT relation between the gaugino mass parameters M_1 and M_2, the mass of the lightest neutralino is essentially unconstrained by collider bounds and precision observables. We conclude by considering also the astrophysics and cosmology of a light neutralino.
1802.06956
Yen-Hsun Lin
Chian-Shu Chen and Yen-Hsun Lin
On the evolution process of two-component dark matter in the Sun
25 pages and 7 figures, minor revision, results unchanged, references added
JHEP 1804 (2018) 074
10.1007/JHEP04(2018)074
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
We introduce dark matter (DM) evolution process in the Sun under a two-component DM (2DM) scenario. Both DM species $\chi$ and $\xi$ with masses heavier than 1 GeV are considered. In this picture, both species could be captured by the Sun through DM-nucleus scattering and DM self-scatterings, e.g. $\chi\chi$ and $\xi\xi$ collisions. In addition, the heterogeneous self-scattering due to $\chi$ and $\xi$ collision is essentially possible in any 2DM models. This new introduced scattering naturally weaves the evolution processes of the two DM species that was assumed to evolve independently. Moreover, the heterogeneous self-scattering enhances the number of DM being captured in the Sun mutually. This effect significantly exists in a broad range of DM mass spectrum. We have studied this phenomena and its implication for the solar-captured DM annihilation rate. It would be crucial to the DM indirect detection when the two masses are close. General formalism of the 2DM evolution in the Sun as well as its kinematics are studied.
[ { "created": "Tue, 20 Feb 2018 04:00:31 GMT", "version": "v1" }, { "created": "Sun, 25 Feb 2018 14:44:19 GMT", "version": "v2" }, { "created": "Wed, 4 Apr 2018 12:48:01 GMT", "version": "v3" } ]
2018-04-18
[ [ "Chen", "Chian-Shu", "" ], [ "Lin", "Yen-Hsun", "" ] ]
We introduce dark matter (DM) evolution process in the Sun under a two-component DM (2DM) scenario. Both DM species $\chi$ and $\xi$ with masses heavier than 1 GeV are considered. In this picture, both species could be captured by the Sun through DM-nucleus scattering and DM self-scatterings, e.g. $\chi\chi$ and $\xi\xi$ collisions. In addition, the heterogeneous self-scattering due to $\chi$ and $\xi$ collision is essentially possible in any 2DM models. This new introduced scattering naturally weaves the evolution processes of the two DM species that was assumed to evolve independently. Moreover, the heterogeneous self-scattering enhances the number of DM being captured in the Sun mutually. This effect significantly exists in a broad range of DM mass spectrum. We have studied this phenomena and its implication for the solar-captured DM annihilation rate. It would be crucial to the DM indirect detection when the two masses are close. General formalism of the 2DM evolution in the Sun as well as its kinematics are studied.
hep-ph/0108115
Keith R. Dienes
Keith R. Dienes
Shape versus Volume: Making Large Flat Extra Dimensions Invisible
9 pages, LaTeX, 5 figures
Phys.Rev.Lett.88:011601,2002
10.1103/PhysRevLett.88.011601
null
hep-ph hep-th
null
Much recent attention has focused on theories with large extra compactified dimensions. However, while the phenomenological implications of the volume moduli associated with such compactifications are well understood, relatively little attention has been devoted to the shape moduli. In this paper, we show that the shape moduli have a dramatic effect on the corresponding Kaluza-Klein spectra: they change the mass gap, induce level crossings, and can even be used to interpolate between theories with different numbers of compactified dimensions. Furthermore, we show that in certain cases it is possible to maintain the ratio between the higher-dimensional and four-dimensional Planck scales while simultaneously increasing the Kaluza-Klein graviton mass gap by an arbitrarily large factor. This mechanism can therefore be used to alleviate (or perhaps even eliminate) many of the experimental bounds on theories with large extra spacetime dimensions.
[ { "created": "Mon, 13 Aug 2001 23:58:15 GMT", "version": "v1" }, { "created": "Wed, 12 Sep 2001 22:32:34 GMT", "version": "v2" }, { "created": "Mon, 19 Nov 2001 01:10:32 GMT", "version": "v3" } ]
2010-11-19
[ [ "Dienes", "Keith R.", "" ] ]
Much recent attention has focused on theories with large extra compactified dimensions. However, while the phenomenological implications of the volume moduli associated with such compactifications are well understood, relatively little attention has been devoted to the shape moduli. In this paper, we show that the shape moduli have a dramatic effect on the corresponding Kaluza-Klein spectra: they change the mass gap, induce level crossings, and can even be used to interpolate between theories with different numbers of compactified dimensions. Furthermore, we show that in certain cases it is possible to maintain the ratio between the higher-dimensional and four-dimensional Planck scales while simultaneously increasing the Kaluza-Klein graviton mass gap by an arbitrarily large factor. This mechanism can therefore be used to alleviate (or perhaps even eliminate) many of the experimental bounds on theories with large extra spacetime dimensions.
2207.08515
Aishwarya Bhatta
Aishwarya Bhatta and Rukmani Mohanta
Delving into new physics in semileptonic $b \to c \tau \bar \nu$ transitions
40 pages, 13 figures, 13 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, several indications of lepton non-universality observables have been perceived in semileptonic $B$ meson decay processes, both in the neutral-current ($b \to s ll $) and charged-current ($b \to c l \bar \nu_l$) transitions. Influenced by these fascinating quotients, we examine the semileptonic decays involving the $b \to c l \bar \nu_l$ quark level transitions. We execute it through a model independent analysis in order to probe the nature of new physics. Taking into consideration the most general effective Hamiltonian, we scrutinize $\Lambda_b \to \Lambda_c \tau \bar \nu_\tau$, $ B_c^+ \to \eta_c \tau^+ \nu_\tau$, and $ B \to D^{**} \tau \bar \nu_\tau$ (where $D^{**} = \{D^*_0, D_1^*, D_1, D_2^*\}$ are the four lightest excited charm mesons) processes, in the presence of new physics. We perform a global fit to different sets of new coefficients, making use of the measurements on $R_{D}$, $R_{D^{*}}$, $R_{J/\psi}$, $P_{\tau}^{D^*}$ and the upper limit on Br($B_c^+ \to \tau^+ \nu_\tau$). We then inspect the effect of constrained new couplings on the branching ratios, forward-backward asymmetry parameters, lepton non-universality ratios (LNU), lepton and hadron polarization asymmetries of these decay modes.
[ { "created": "Mon, 18 Jul 2022 11:17:28 GMT", "version": "v1" }, { "created": "Tue, 15 Aug 2023 10:51:11 GMT", "version": "v2" } ]
2023-08-16
[ [ "Bhatta", "Aishwarya", "" ], [ "Mohanta", "Rukmani", "" ] ]
Recently, several indications of lepton non-universality observables have been perceived in semileptonic $B$ meson decay processes, both in the neutral-current ($b \to s ll $) and charged-current ($b \to c l \bar \nu_l$) transitions. Influenced by these fascinating quotients, we examine the semileptonic decays involving the $b \to c l \bar \nu_l$ quark level transitions. We execute it through a model independent analysis in order to probe the nature of new physics. Taking into consideration the most general effective Hamiltonian, we scrutinize $\Lambda_b \to \Lambda_c \tau \bar \nu_\tau$, $ B_c^+ \to \eta_c \tau^+ \nu_\tau$, and $ B \to D^{**} \tau \bar \nu_\tau$ (where $D^{**} = \{D^*_0, D_1^*, D_1, D_2^*\}$ are the four lightest excited charm mesons) processes, in the presence of new physics. We perform a global fit to different sets of new coefficients, making use of the measurements on $R_{D}$, $R_{D^{*}}$, $R_{J/\psi}$, $P_{\tau}^{D^*}$ and the upper limit on Br($B_c^+ \to \tau^+ \nu_\tau$). We then inspect the effect of constrained new couplings on the branching ratios, forward-backward asymmetry parameters, lepton non-universality ratios (LNU), lepton and hadron polarization asymmetries of these decay modes.
2407.10491
Yossathorn Tawabutr
Yossathorn Tawabutr
Contribution to the Proton Spin Puzzle from Helicity at small Bjorken $x$
7 pages, 0 figures; contribution to DIS2024
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The contribution to proton helicity from the spins of quarks and gluons at small Bjorken $x$ can be conveniently studied through the small-$x$ helicity evolution. Recently, it has been employed in a global analysis that includes polarized inclusive and semi-inclusive deep-inelastic scattering measurements at small $x$. The analysis demonstrates an excellent agreement between the evolution and the data, but its predictions contain large uncertainties owing to the large number of free parameters in the initial conditions. The latest development aims to mitigate this issue by employing the valence quark model in the polarized proton target in order to replace most of the free parameters in the initial conditions by the physical information from the proton model.
[ { "created": "Mon, 15 Jul 2024 07:31:48 GMT", "version": "v1" } ]
2024-07-16
[ [ "Tawabutr", "Yossathorn", "" ] ]
The contribution to proton helicity from the spins of quarks and gluons at small Bjorken $x$ can be conveniently studied through the small-$x$ helicity evolution. Recently, it has been employed in a global analysis that includes polarized inclusive and semi-inclusive deep-inelastic scattering measurements at small $x$. The analysis demonstrates an excellent agreement between the evolution and the data, but its predictions contain large uncertainties owing to the large number of free parameters in the initial conditions. The latest development aims to mitigate this issue by employing the valence quark model in the polarized proton target in order to replace most of the free parameters in the initial conditions by the physical information from the proton model.
2406.01628
Darius Jurciukonis
Darius Jur\v{c}iukonis, Lu\'is Lavoura
On the bounded-from-below conditions for the extension of the SM through a scalar quadruplet
16 pages, 1 figure
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the scalar potential of the extension of the Standard Model through a scalar quadruplet with hypercharge either 1/2 or 3/2. That potential contains a term that had not been previously taken into account. We write down the full unitarity conditions. We use a numerical scan of phase space instead of attempting to derive fully analytical bounded-from-below conditions.
[ { "created": "Sat, 1 Jun 2024 08:46:48 GMT", "version": "v1" } ]
2024-06-05
[ [ "Jurčiukonis", "Darius", "" ], [ "Lavoura", "Luís", "" ] ]
We study the scalar potential of the extension of the Standard Model through a scalar quadruplet with hypercharge either 1/2 or 3/2. That potential contains a term that had not been previously taken into account. We write down the full unitarity conditions. We use a numerical scan of phase space instead of attempting to derive fully analytical bounded-from-below conditions.
1003.1270
Paulo S\'ergio Rodrigues da Silva
C. A. de S. Pires, F. Queiroz, P. S. Rodrigues da Silva
A minimal 3-3-1 model with naturally sub-eV neutrinos
14 pages, no figure, some corrections on the proton decay operators, conclusions unchanged, matches published version in PRD
Phys.Rev.D82:065018,2010
10.1103/PhysRevD.82.065018
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the original version of the minimal SU(3)_C x SU(3)_L x U(1)_N model the masses of all quarks are correctly obtained by introducing three scalar triplets into the model, meanwhile the lepton mass generation requires the introduction of at least one scalar sextet. In this work we show that this scalar sextet is unable to yield the correct neutrino masses and mixing. In order to solve this puzzle in the most economical way, we evoke an additional Z_3 discrete symmetry, without including this sextet in the scalar spectrum, and propose a truly minimal 3-3-1 model capable of generating the correct masses and mixing of all fermions. Moreover, we show that our proposal leads to naturally light neutrinos with masses in the eV range, obtained with three scalar triplets only. Finally, the so called minimal 3-3-1 model is also in danger due to the presence of undesirable effective operators that lead to proton decay unless they are suppressed by extremely small couplings or, as we choose to employ in this work, are eliminated by some discrete symmetry.
[ { "created": "Fri, 5 Mar 2010 14:32:35 GMT", "version": "v1" }, { "created": "Fri, 22 Oct 2010 02:22:43 GMT", "version": "v2" } ]
2012-01-27
[ [ "Pires", "C. A. de S.", "" ], [ "Queiroz", "F.", "" ], [ "da Silva", "P. S. Rodrigues", "" ] ]
In the original version of the minimal SU(3)_C x SU(3)_L x U(1)_N model the masses of all quarks are correctly obtained by introducing three scalar triplets into the model, meanwhile the lepton mass generation requires the introduction of at least one scalar sextet. In this work we show that this scalar sextet is unable to yield the correct neutrino masses and mixing. In order to solve this puzzle in the most economical way, we evoke an additional Z_3 discrete symmetry, without including this sextet in the scalar spectrum, and propose a truly minimal 3-3-1 model capable of generating the correct masses and mixing of all fermions. Moreover, we show that our proposal leads to naturally light neutrinos with masses in the eV range, obtained with three scalar triplets only. Finally, the so called minimal 3-3-1 model is also in danger due to the presence of undesirable effective operators that lead to proton decay unless they are suppressed by extremely small couplings or, as we choose to employ in this work, are eliminated by some discrete symmetry.
2005.05194
Ezequiel Alvarez
Ezequiel Alvarez, Mariel Est\'evez, Rosa Mar\'ia Sand\'a Seoane (ICAS, Argentina)
Z'-explorer: a simple tool to probe Z' models against LHC data
28 pages. Github for Z'-explorer: github.com/ro-sanda/Z--explorer. (Application examples section revised, no changes in software.)
Comput.Phys.Commun. 269 (2021) 108144
10.1016/j.cpc.2021.108144
ICAS-050-20
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
New Physics model building requires a vast number of cross-checks against available experimental results. In particular, new neutral, colorless, spin-1 bosons $Z'$, can be found in many models. We introduce in this work a new easy-to-use software Z'-explorer which probes $Z'$ models to all available decay channels at LHC. This program scrutinizes the parameter space of the model to determine which part is still allowed, which is to be shortly explored, and which channel is the most sensitive in each region of parameter space. User does not need to implement the model nor run any Monte Carlo simulation, but instead just needs to use the $Z'$ mass and its couplings to Standard Model particles. We describe Z'-explorer backend and provide instructions to use it from its frontend, while applying it to a variety of $Z'$ models. In particular we show Z'-explorer application and utility in a sequential Standard Model, a B-L $Z'$ and a simplified two-sector or Warped/Composite model. The output of the program condenses the phenomenology of the model features, the experimental techniques and the search strategies in each channel in an enriching outcome. We find that compelling add-ons to the software would be to include correlation between decay channels, low-energy physics results, and Dark Matter searches. The software is open-source ready to use, and available for modifications, improvements and updates by the community.
[ { "created": "Mon, 11 May 2020 15:37:42 GMT", "version": "v1" }, { "created": "Sun, 27 Sep 2020 14:53:05 GMT", "version": "v2" } ]
2021-12-14
[ [ "Alvarez", "Ezequiel", "", "ICAS,\n Argentina" ], [ "Estévez", "Mariel", "", "ICAS,\n Argentina" ], [ "Seoane", "Rosa María Sandá", "", "ICAS,\n Argentina" ] ]
New Physics model building requires a vast number of cross-checks against available experimental results. In particular, new neutral, colorless, spin-1 bosons $Z'$, can be found in many models. We introduce in this work a new easy-to-use software Z'-explorer which probes $Z'$ models to all available decay channels at LHC. This program scrutinizes the parameter space of the model to determine which part is still allowed, which is to be shortly explored, and which channel is the most sensitive in each region of parameter space. User does not need to implement the model nor run any Monte Carlo simulation, but instead just needs to use the $Z'$ mass and its couplings to Standard Model particles. We describe Z'-explorer backend and provide instructions to use it from its frontend, while applying it to a variety of $Z'$ models. In particular we show Z'-explorer application and utility in a sequential Standard Model, a B-L $Z'$ and a simplified two-sector or Warped/Composite model. The output of the program condenses the phenomenology of the model features, the experimental techniques and the search strategies in each channel in an enriching outcome. We find that compelling add-ons to the software would be to include correlation between decay channels, low-energy physics results, and Dark Matter searches. The software is open-source ready to use, and available for modifications, improvements and updates by the community.
0802.3367
Agnes Grau
R.M. Godbole, A. Grau, G. Pancheri and Y.N. Srivastava
Minijets, soft gluon resummation and photon cross-sections
7 pages, 5 figures. Presented at Photon2007, Paris, July 2007. Requires photon2007.cls
Nucl.Phys.Proc.Suppl.184:85-90,2008
10.1016/j.nuclphysbps.2008.09.143
LNF - 08 / 5(P)
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compare the high energy behaviour of hadronic photon-photon cross-sections in different models. We find that the photon-photon cross-section appears to rise faster than the purely hadronic ones (proton-proton and proton-antiproton).
[ { "created": "Fri, 22 Feb 2008 19:24:13 GMT", "version": "v1" } ]
2008-12-18
[ [ "Godbole", "R. M.", "" ], [ "Grau", "A.", "" ], [ "Pancheri", "G.", "" ], [ "Srivastava", "Y. N.", "" ] ]
We compare the high energy behaviour of hadronic photon-photon cross-sections in different models. We find that the photon-photon cross-section appears to rise faster than the purely hadronic ones (proton-proton and proton-antiproton).
2012.13128
Leonid P Kaptari
Yu.D. Chernichenko, L.P. Kaptari, O. P. Solovtsova
Relativistic Coulomb S-factor of Two Spinor Particles with Arbitrary Masses
23 pages, 5 figures
null
null
null
hep-ph nucl-th
http://creativecommons.org/licenses/by/4.0/
A new resummation of the $S$-factor of a composite system of two relativistic spin-1/2 particles of arbitrary masses interacting via a Coulomb-like chromodynamical potential is presented. The analysis is performed in the framework of a relativistic quasipotential approach based on the Hamiltonian formulation of the covariant quantum field theory in the relativistic configuration representation. The pseudoscalar, vector, and pseudovector systems are considered and the behaviour of the $S$-factor near the threshold and in the relativistic limit is investigated in detail. The spin dependence of the $S$-factors is discussed as well. It is argued that at the threshold the contribution of spins significantly reduces the Sommerfeld effect, while at ultrarelativistic velocities their role diminishes and the $S$-factor becomes basically the same as for the spinless systems. A connection between the new and previously obtained S-factors for spinless particles of arbitrary masses and for relativistic spinor particles of equal masses is established.
[ { "created": "Thu, 24 Dec 2020 06:27:31 GMT", "version": "v1" } ]
2020-12-25
[ [ "Chernichenko", "Yu. D.", "" ], [ "Kaptari", "L. P.", "" ], [ "Solovtsova", "O. P.", "" ] ]
A new resummation of the $S$-factor of a composite system of two relativistic spin-1/2 particles of arbitrary masses interacting via a Coulomb-like chromodynamical potential is presented. The analysis is performed in the framework of a relativistic quasipotential approach based on the Hamiltonian formulation of the covariant quantum field theory in the relativistic configuration representation. The pseudoscalar, vector, and pseudovector systems are considered and the behaviour of the $S$-factor near the threshold and in the relativistic limit is investigated in detail. The spin dependence of the $S$-factors is discussed as well. It is argued that at the threshold the contribution of spins significantly reduces the Sommerfeld effect, while at ultrarelativistic velocities their role diminishes and the $S$-factor becomes basically the same as for the spinless systems. A connection between the new and previously obtained S-factors for spinless particles of arbitrary masses and for relativistic spinor particles of equal masses is established.
hep-ph/0411389
Schoeffel Laurent
E. Perez, L. Schoeffel, L. Favart
MILOU : a Monte-Carlo for Deeply Virtual Compton Scattering
18 pages, 9 figures
null
null
DESY-report 04-228
hep-ph
null
In this note, we present a new generator for Deeply Virtual Compton Scattering processes. This generator is based on formalism of Generalized Partons Distributions evolved at Next Leading Order (NLO). In the following we give a brief description of this formalism and we explain the main features of the generator for the elastic reactions, as well as for proton dissociation.
[ { "created": "Tue, 30 Nov 2004 09:14:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Perez", "E.", "" ], [ "Schoeffel", "L.", "" ], [ "Favart", "L.", "" ] ]
In this note, we present a new generator for Deeply Virtual Compton Scattering processes. This generator is based on formalism of Generalized Partons Distributions evolved at Next Leading Order (NLO). In the following we give a brief description of this formalism and we explain the main features of the generator for the elastic reactions, as well as for proton dissociation.
1609.09513
Francesco Bigazzi
Lorenzo Bartolini, Francesco Bigazzi, Stefano Bolognesi, Aldo L. Cotrone, Andrea Manenti
Neutron electric dipole moment from gauge/string duality
Latex, 4 pages; v2: minor corrections, few comments added
Phys. Rev. Lett. 118, 091601 (2017)
10.1103/PhysRevLett.118.091601
null
hep-ph hep-lat hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the electric dipole moment of nucleons in the large $N_c$ QCD model by Witten, Sakai and Sugimoto with $N_f=2$ degenerate massive flavors. Baryons in the model are instantonic solitons of an effective five-dimensional action describing the whole tower of mesonic fields. We find that the dipole electromagnetic form factor of the nucleons, induced by a finite topological $\theta$ angle, exhibits complete vector meson dominance. We are able to evaluate the contribution of each vector meson to the final result - a small number of modes are relevant to obtain an accurate estimate. Extrapolating the model parameters to real QCD data, the neutron electric dipole moment is evaluated to be $d_n = 1.8 \cdot 10^{-16}\, \theta\;e\cdot \mathrm{cm}$. The electric dipole moment of the proton is exactly the opposite.
[ { "created": "Thu, 29 Sep 2016 20:18:06 GMT", "version": "v1" }, { "created": "Tue, 11 Oct 2016 06:45:05 GMT", "version": "v2" } ]
2017-03-08
[ [ "Bartolini", "Lorenzo", "" ], [ "Bigazzi", "Francesco", "" ], [ "Bolognesi", "Stefano", "" ], [ "Cotrone", "Aldo L.", "" ], [ "Manenti", "Andrea", "" ] ]
We compute the electric dipole moment of nucleons in the large $N_c$ QCD model by Witten, Sakai and Sugimoto with $N_f=2$ degenerate massive flavors. Baryons in the model are instantonic solitons of an effective five-dimensional action describing the whole tower of mesonic fields. We find that the dipole electromagnetic form factor of the nucleons, induced by a finite topological $\theta$ angle, exhibits complete vector meson dominance. We are able to evaluate the contribution of each vector meson to the final result - a small number of modes are relevant to obtain an accurate estimate. Extrapolating the model parameters to real QCD data, the neutron electric dipole moment is evaluated to be $d_n = 1.8 \cdot 10^{-16}\, \theta\;e\cdot \mathrm{cm}$. The electric dipole moment of the proton is exactly the opposite.
0710.5878
Alexander Nesterenko
A.V. Nesterenko
Adler function in the analytic approach to QCD
Talk given at Ninth Workshop on Nonperturbative QCD, 4 - 8 June 2007, Paris, France; 6 pages, 1 figure
ECONFC0706044:25,2007
null
null
hep-ph hep-th
null
The low energy behavior of the Adler function D(Q^2) is studied by employing recently derived integral representation for the latter. This representation embodies the nonperturbative constraints on D(Q^2), in particular, it retains the effects due to the nonvanishing pion mass. The Adler function is calculated within the developed approach by making use of its perturbative approximation as the only additional input. The obtained result agrees with the experimental prediction for the Adler function in the entire energy range and possesses remarkable stability with respect to the higher loop corrections.
[ { "created": "Wed, 31 Oct 2007 15:17:05 GMT", "version": "v1" } ]
2008-11-26
[ [ "Nesterenko", "A. V.", "" ] ]
The low energy behavior of the Adler function D(Q^2) is studied by employing recently derived integral representation for the latter. This representation embodies the nonperturbative constraints on D(Q^2), in particular, it retains the effects due to the nonvanishing pion mass. The Adler function is calculated within the developed approach by making use of its perturbative approximation as the only additional input. The obtained result agrees with the experimental prediction for the Adler function in the entire energy range and possesses remarkable stability with respect to the higher loop corrections.
2403.17501
Florian Herren
Erik J. Gustafson, Florian Herren, Ruth S. Van de Water, Raynette van Tonder, Michael L. Wagman
Model-independent description of $B\rightarrow D \pi \ell \nu$ decays
Presented at the 12th Workshop on the CKM Unitarity Triangle, 18-22 September 2023, Santiago de Compostela
null
null
ZU-TH 17/24
hep-ph hep-ex hep-lat
http://creativecommons.org/licenses/by/4.0/
In this contribution we present a novel, model-independent description of semileptonic $B\rightarrow D \pi \ell \nu$ decays. In addition, we discuss recent developments in the understanding of coupled-channel $D \pi$-$D \eta$-$D_s K$ S-wave scattering and, for the first time, apply them to semileptonic decays. We not only obtain model-independent predictions for kinematic distributions in $B\rightarrow D \pi \ell \nu$ decays, but also rule out the hypothesis that the gap between the inclusive $B\rightarrow X\ell\nu$ branching fraction and the sum over exclusive channels is made up predominantly by $B\rightarrow D^{(\ast)} \eta \ell \nu$ decays.
[ { "created": "Tue, 26 Mar 2024 09:00:32 GMT", "version": "v1" } ]
2024-03-27
[ [ "Gustafson", "Erik J.", "" ], [ "Herren", "Florian", "" ], [ "Van de Water", "Ruth S.", "" ], [ "van Tonder", "Raynette", "" ], [ "Wagman", "Michael L.", "" ] ]
In this contribution we present a novel, model-independent description of semileptonic $B\rightarrow D \pi \ell \nu$ decays. In addition, we discuss recent developments in the understanding of coupled-channel $D \pi$-$D \eta$-$D_s K$ S-wave scattering and, for the first time, apply them to semileptonic decays. We not only obtain model-independent predictions for kinematic distributions in $B\rightarrow D \pi \ell \nu$ decays, but also rule out the hypothesis that the gap between the inclusive $B\rightarrow X\ell\nu$ branching fraction and the sum over exclusive channels is made up predominantly by $B\rightarrow D^{(\ast)} \eta \ell \nu$ decays.
0712.0298
Marcello Lissia
G. Bellini, G. Fiorentini, A. Ianni, M. Lissia, F. Mantovani, and O. Smirnov
Nuclear physics inputs needed for geo-neutrino studies
6 pages, 3 figures. Proceedings of the International Conference on Topics in Astroparticle and Underground Physics (TAUP) 2007, Sendai, Japan, September 11-15, 2007. To appear in Journal of Physics: Conference Series
J.Phys.Conf.Ser.120:052007,2008
10.1088/1742-6596/120/5/052007
null
hep-ph astro-ph nucl-ex physics.geo-ph
null
Geo-neutrino studies are based on theoretical estimates of geo-neutrino spectra. We propose a method for a direct measurement of the energy distribution of antineutrinos from decays of long-lived radioactive isotopes.
[ { "created": "Mon, 3 Dec 2007 14:23:39 GMT", "version": "v1" } ]
2008-11-26
[ [ "Bellini", "G.", "" ], [ "Fiorentini", "G.", "" ], [ "Ianni", "A.", "" ], [ "Lissia", "M.", "" ], [ "Mantovani", "F.", "" ], [ "Smirnov", "O.", "" ] ]
Geo-neutrino studies are based on theoretical estimates of geo-neutrino spectra. We propose a method for a direct measurement of the energy distribution of antineutrinos from decays of long-lived radioactive isotopes.
0910.3528
Thorsten Renk
Thorsten Renk
The Nuclear Suppression Factor for P_T increasing towards the Kinematic Limit
9 pages, 5 figures, typos corrected and more details of the calculation given
Phys.Rev.C81:014906,2010
10.1103/PhysRevC.81.014906
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The suppression of high transverse momentum P_T hadron production in ultrarelativistic heavy-ion (A-A) collisions as compared to the scaled expectation from proton-proton (p-p) collisions expressed as the nuclear modification factor R_AA is experimentally well established and can be traced back to interactions between the hard parton shower and the soft bulk matter. Physical intuition suggests that the medium modification should cease to be important when the hard scale of parton production is much larger than the typical momentum scale in the medium (e.g. the temperature T) and that consequently R_AA(P_T) -> 1 for P_T >> T. However, R_AA is not a 'simple' observable, but rather results from many different mechanisms which influence what happens when P_T increases. In particular, R_AA does not necessarily approch unity even if the hadron momentum is probed at the kinematic limit of the reaction. The aim of this work is to identify and discuss such mechanisms and to present different model expectations of what one would find if one could measure suppression out to the kinematic limit for hard hadron production and give predictions for the P_T dependence at both RHIC and LHC.
[ { "created": "Mon, 19 Oct 2009 11:29:37 GMT", "version": "v1" }, { "created": "Mon, 26 Oct 2009 12:50:07 GMT", "version": "v2" }, { "created": "Tue, 5 Jan 2010 11:27:47 GMT", "version": "v3" } ]
2010-04-06
[ [ "Renk", "Thorsten", "" ] ]
The suppression of high transverse momentum P_T hadron production in ultrarelativistic heavy-ion (A-A) collisions as compared to the scaled expectation from proton-proton (p-p) collisions expressed as the nuclear modification factor R_AA is experimentally well established and can be traced back to interactions between the hard parton shower and the soft bulk matter. Physical intuition suggests that the medium modification should cease to be important when the hard scale of parton production is much larger than the typical momentum scale in the medium (e.g. the temperature T) and that consequently R_AA(P_T) -> 1 for P_T >> T. However, R_AA is not a 'simple' observable, but rather results from many different mechanisms which influence what happens when P_T increases. In particular, R_AA does not necessarily approch unity even if the hadron momentum is probed at the kinematic limit of the reaction. The aim of this work is to identify and discuss such mechanisms and to present different model expectations of what one would find if one could measure suppression out to the kinematic limit for hard hadron production and give predictions for the P_T dependence at both RHIC and LHC.
1609.01694
Stuart Raby
Stuart Raby
Axion star collisions with Neutron stars and Fast Radio Bursts
10 pages, published version without figure
Phys. Rev. D 94, 103004 (2016)
10.1103/PhysRevD.94.103004
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Axions may make a significant contribution to the dark matter of the universe. It has been suggested that these dark matter axions may condense into localized clumps, called "axion stars." In this paper we argue that collisions of dilute axion stars with neutron stars, of the type known as "magnetars," may be the origin of most of the observed fast radio bursts. This idea is a variation of an idea originally proposed by Iwazaki. However, instead of the surface effect of Iwazaki, we propose a perhaps stronger volume effect caused by the induced time dependent electric dipole moment of neutrons.
[ { "created": "Tue, 6 Sep 2016 18:50:04 GMT", "version": "v1" }, { "created": "Thu, 8 Sep 2016 17:21:20 GMT", "version": "v2" }, { "created": "Tue, 18 Oct 2016 17:27:05 GMT", "version": "v3" }, { "created": "Thu, 8 Dec 2016 19:33:52 GMT", "version": "v4" } ]
2016-12-09
[ [ "Raby", "Stuart", "" ] ]
Axions may make a significant contribution to the dark matter of the universe. It has been suggested that these dark matter axions may condense into localized clumps, called "axion stars." In this paper we argue that collisions of dilute axion stars with neutron stars, of the type known as "magnetars," may be the origin of most of the observed fast radio bursts. This idea is a variation of an idea originally proposed by Iwazaki. However, instead of the surface effect of Iwazaki, we propose a perhaps stronger volume effect caused by the induced time dependent electric dipole moment of neutrons.
hep-ph/9708379
Tony Smith
Frank Tony Smith
From Sets to Quarks
Higgs mass revised to 146 GeV, also miscellaneous additions and typo corrections, 164 pages, LaTeX
null
null
TS-TH-97-1
hep-ph
null
From sets and simple operations on sets, a Feynman Checkerboard physics model is constructed that allows computation of force strength constants and constituent mass ratios of elementary particles, with a Lagrangian structure that gives a Higgs scalar particle mass of about 146 GeV and a Higgs scalar field vacuum expectation value of about 252 GeV, giving a tree level constituent Truth Quark (top quark) mass of roughly 130 GeV, which is (in my opinion) supported by dileptonic events and some semileptonic events. See http://galaxy.cau.edu/tsmith/HDFCmodel.html and http://www.innerx.net/personal/tsmith/HDFCmodel.html Chapter 1 - Introduction. Chapter 2 - From Sets to Clifford Algebras. Chapter 3 - Octonions and E8 lattices. Chapter 4 - E8 spacetime and particles. Chapter 5 - HyperDiamond Lattices. Chapter 6 - Internal Symmetry Space. Chapter 7 - Feynman Checkerboards. Chapter 8 - Charge = Amplitude to Emit Gauge Boson. Chapter 9 - Mass = Amplitude to Change Direction. Chapter 10 - Protons, Pions, and Physical Gravitons.
[ { "created": "Sun, 17 Aug 1997 19:26:51 GMT", "version": "v1" }, { "created": "Sun, 14 Jun 1998 09:14:26 GMT", "version": "v2" } ]
2016-09-06
[ [ "Smith", "Frank Tony", "" ] ]
From sets and simple operations on sets, a Feynman Checkerboard physics model is constructed that allows computation of force strength constants and constituent mass ratios of elementary particles, with a Lagrangian structure that gives a Higgs scalar particle mass of about 146 GeV and a Higgs scalar field vacuum expectation value of about 252 GeV, giving a tree level constituent Truth Quark (top quark) mass of roughly 130 GeV, which is (in my opinion) supported by dileptonic events and some semileptonic events. See http://galaxy.cau.edu/tsmith/HDFCmodel.html and http://www.innerx.net/personal/tsmith/HDFCmodel.html Chapter 1 - Introduction. Chapter 2 - From Sets to Clifford Algebras. Chapter 3 - Octonions and E8 lattices. Chapter 4 - E8 spacetime and particles. Chapter 5 - HyperDiamond Lattices. Chapter 6 - Internal Symmetry Space. Chapter 7 - Feynman Checkerboards. Chapter 8 - Charge = Amplitude to Emit Gauge Boson. Chapter 9 - Mass = Amplitude to Change Direction. Chapter 10 - Protons, Pions, and Physical Gravitons.
1112.4402
Stefano Nicotri
Pietro Colangelo, Floriana Giannuzzi, Stefano Nicotri, Vincenzo Tangorra
Temperature and quark density effects on the chiral condensate: an AdS/QCD study
13 pages, 3 figures, published on EPJC
The European Physical Journal C, Volume 72, Issue 8, 2096 (2012)
10.1140/epjc/s10052-012-2096-9
BARI-TH/2011-648
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the dependence of the chiral condensate $<\bar qq>$ on the temperature and quark density using the soft-wall holographic model of QCD, adopting geometries with black holes at finite temperature and quark chemical potential $\mu$. We find that, for $\mu$ below a critical value, increasing the temperature the condensate decreases and vanishes at a temperature $\tilde T\simeq 210$ MeV (at $\mu=0$). An analogous behaviour is observed increasing the chemical potential at fixed temperature. These results agree with the findings obtained by other methods. We also comment on the robustness of the results if geometries not involving black holes are adopted at low temperature, and an Hawking-Page transition is implemented.
[ { "created": "Mon, 19 Dec 2011 16:54:30 GMT", "version": "v1" }, { "created": "Mon, 27 Aug 2012 11:03:27 GMT", "version": "v2" } ]
2012-08-28
[ [ "Colangelo", "Pietro", "" ], [ "Giannuzzi", "Floriana", "" ], [ "Nicotri", "Stefano", "" ], [ "Tangorra", "Vincenzo", "" ] ]
We investigate the dependence of the chiral condensate $<\bar qq>$ on the temperature and quark density using the soft-wall holographic model of QCD, adopting geometries with black holes at finite temperature and quark chemical potential $\mu$. We find that, for $\mu$ below a critical value, increasing the temperature the condensate decreases and vanishes at a temperature $\tilde T\simeq 210$ MeV (at $\mu=0$). An analogous behaviour is observed increasing the chemical potential at fixed temperature. These results agree with the findings obtained by other methods. We also comment on the robustness of the results if geometries not involving black holes are adopted at low temperature, and an Hawking-Page transition is implemented.
1712.08648
Jihn E. Kim
Jihn E. Kim, Soonkeon Nam, Yannis K. Semertzidis
Fate of global symmetries in the Universe: QCD axion, quintessential axion and trans-Planckian inflaton decay-constant
41 pages with 27 figures
null
10.1142/S0217751X18300028
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Pseudoscalars appearing in particle physics are reviewd systematically. From the fundamental point of view at an ultra-violat completed theory, they can be light if they are realized as pseudo-Goldstone bosons of some spontaneously broken global symmetries. The spontaneous breaking scale is parametrized by the decay constant $f$. The global symmetry is defined by the lowest order terms allowed in the effective theory consistent with the gauge symmetry in question. Since any global symmetry is known to be broken at least by quantum gravitational effects, all pseudoscalars should be massive. The mass scale is determined by $f$ and the explicit breaking terms $\Delta V$ in the effective potential and also anomaly terms $\Delta\Lambda^4_G$ for some non-Abelian gauge groups $G$. The well-known example by non-Abelian gauge group breaking is the potential for the "invisible" QCD axion, via the Peccei-Quinn symmetry, which constitutes a major part of this review. Even if there is no breaking terms from gauge anomalies, there can be explicit breaking terms $\Delta V$ in the potential in which case the leading term suppressed by $f$ determines the pseudoscalar mass scale. If the breaking term is extremely small and the decay constant is trans-Planckian, the corresponding pseudoscalar can be a candidate for a `quintessential axion'. In general, $(\Delta V)^{1/4}$ is considered to be smaller than $f$, and hence the pseudo-Goldstone boson mass scales are considered to be smaller than the decay constants. In such a case, the potential of the pseudo-Goldstone boson at the grand unification scale is sufficiently flat near the top of the potential that it can be a good candidate for an inflationary model, which is known as `natural inflation'. We review all these ideas in the bosonic collective motion framework.
[ { "created": "Fri, 22 Dec 2017 20:29:28 GMT", "version": "v1" }, { "created": "Mon, 29 Jan 2018 02:37:28 GMT", "version": "v2" } ]
2018-03-14
[ [ "Kim", "Jihn E.", "" ], [ "Nam", "Soonkeon", "" ], [ "Semertzidis", "Yannis K.", "" ] ]
Pseudoscalars appearing in particle physics are reviewd systematically. From the fundamental point of view at an ultra-violat completed theory, they can be light if they are realized as pseudo-Goldstone bosons of some spontaneously broken global symmetries. The spontaneous breaking scale is parametrized by the decay constant $f$. The global symmetry is defined by the lowest order terms allowed in the effective theory consistent with the gauge symmetry in question. Since any global symmetry is known to be broken at least by quantum gravitational effects, all pseudoscalars should be massive. The mass scale is determined by $f$ and the explicit breaking terms $\Delta V$ in the effective potential and also anomaly terms $\Delta\Lambda^4_G$ for some non-Abelian gauge groups $G$. The well-known example by non-Abelian gauge group breaking is the potential for the "invisible" QCD axion, via the Peccei-Quinn symmetry, which constitutes a major part of this review. Even if there is no breaking terms from gauge anomalies, there can be explicit breaking terms $\Delta V$ in the potential in which case the leading term suppressed by $f$ determines the pseudoscalar mass scale. If the breaking term is extremely small and the decay constant is trans-Planckian, the corresponding pseudoscalar can be a candidate for a `quintessential axion'. In general, $(\Delta V)^{1/4}$ is considered to be smaller than $f$, and hence the pseudo-Goldstone boson mass scales are considered to be smaller than the decay constants. In such a case, the potential of the pseudo-Goldstone boson at the grand unification scale is sufficiently flat near the top of the potential that it can be a good candidate for an inflationary model, which is known as `natural inflation'. We review all these ideas in the bosonic collective motion framework.
2211.06275
Brian Henning
Luk\'a\v{s} Gr\'af, Brian Henning, Xiaochuan Lu, Tom Melia, Hitoshi Murayama
Hilbert Series, the Higgs Mechanism, and HEFT
33 pages + an appendix, 1 ancillary Mathematica file
null
10.1007/JHEP02(2023)064
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We expand Hilbert series technologies in effective field theory for the inclusion of massive particles, enabling, among other things, the enumeration of operator bases for non-linearly realized gauge theories. We find that the Higgs mechanism is manifest at the level of the Hilbert series, as expected for the partition function of an $S$-matrix that is subject to the Goldstone equivalence theorem. In addition to massive vectors, we detail how other massive, spinning particles can be studied with Hilbert series; in particular, we spell out the ingredients for massive gravity in general spacetime dimensions. Further methodology is introduced to enable Hilbert series to capture the effect of spurion fields acquiring vevs. We apply the techniques to the Higgs Effective Field Theory (HEFT), providing a systematic enumeration of its operator basis. This is achieved both from a direct and a custodial symmetry spurion-based approach; we compare and contrast the two approaches, and our results to those appearing in previous literature.
[ { "created": "Fri, 11 Nov 2022 15:32:47 GMT", "version": "v1" } ]
2023-03-01
[ [ "Gráf", "Lukáš", "" ], [ "Henning", "Brian", "" ], [ "Lu", "Xiaochuan", "" ], [ "Melia", "Tom", "" ], [ "Murayama", "Hitoshi", "" ] ]
We expand Hilbert series technologies in effective field theory for the inclusion of massive particles, enabling, among other things, the enumeration of operator bases for non-linearly realized gauge theories. We find that the Higgs mechanism is manifest at the level of the Hilbert series, as expected for the partition function of an $S$-matrix that is subject to the Goldstone equivalence theorem. In addition to massive vectors, we detail how other massive, spinning particles can be studied with Hilbert series; in particular, we spell out the ingredients for massive gravity in general spacetime dimensions. Further methodology is introduced to enable Hilbert series to capture the effect of spurion fields acquiring vevs. We apply the techniques to the Higgs Effective Field Theory (HEFT), providing a systematic enumeration of its operator basis. This is achieved both from a direct and a custodial symmetry spurion-based approach; we compare and contrast the two approaches, and our results to those appearing in previous literature.
1404.5182
Toshifumi Yamada
Cheng-Wei Chiang, Toshifumi Yamada
Electroweak Phase Transition in Georgi-Machacek Model
null
null
10.1016/j.physletb.2014.06.048
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Georgi-Machacek model extends the standard model Higgs sector by adding two isospin triplet scalar fields and imposing global SU(2)$_R$ symmetry on them. A feature of the model is that the triplets can acquire a large vacuum expectation value without conflicting with the current experimental bound on the $\rho$ parameter. We investigate the electroweak phase transition in the Georgi-Machacek model by evaluating the finite-temperature effective potential of the Higgs sector. The electroweak phase transition can be sufficiently strong in a large parameter space when the triplets acquire a vacuum expectation value of $O(10)$ GeV, opening a possibility to realize successful electroweak baryogenesis.
[ { "created": "Mon, 21 Apr 2014 12:51:30 GMT", "version": "v1" } ]
2015-06-19
[ [ "Chiang", "Cheng-Wei", "" ], [ "Yamada", "Toshifumi", "" ] ]
The Georgi-Machacek model extends the standard model Higgs sector by adding two isospin triplet scalar fields and imposing global SU(2)$_R$ symmetry on them. A feature of the model is that the triplets can acquire a large vacuum expectation value without conflicting with the current experimental bound on the $\rho$ parameter. We investigate the electroweak phase transition in the Georgi-Machacek model by evaluating the finite-temperature effective potential of the Higgs sector. The electroweak phase transition can be sufficiently strong in a large parameter space when the triplets acquire a vacuum expectation value of $O(10)$ GeV, opening a possibility to realize successful electroweak baryogenesis.
1711.01930
Zhiguang Xiao
Zhi-Yong Zhou, Zhiguang Xiao
Comprehending Isospin breaking effects of $X(3872)$ in a Friedrichs-model-like scheme
13 pages, 4 figures
Phys. Rev. D 97, 034011 (2018)
10.1103/PhysRevD.97.034011
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently, we have shown that the $X(3872)$ state can be naturally generated as a bound state by incorporating the hadron interactions into the Godfrey-Isgur quark model using the Friedrichs-like model combined with the QPC model, in which the wave function for the $X(3872)$ as a combination of the bare $c\bar c$ state and the continuum states can also be obtained. Under this scheme, we now investigate the isospin breaking effect of $X(3872)$ in its decays to $J/\psi\pi^+\pi^-$ and $J/\psi\pi^+\pi^-\pi^0$. By Considering its dominant continuum parts coupling to $J/\psi\rho$ and $J/\psi\omega$ through the quark rearrangement process, one could obtain the reasonable ratio of $\mathcal{B}(X(3872)\rightarrow J/\psi\pi^+\pi^-\pi^0)/\mathcal{B}(X(3872)\rightarrow J/\psi\pi^+\pi^-)\simeq (0.58\sim 0.92)$. It is also shown that the $\bar D D^*$ invariant mass distributions in the $B\rightarrow \bar D D^* K$ decays could be understood qualitatively at the same time. This scheme may provide more insight to understand the enigmatic nature of the $X(3872)$ state.
[ { "created": "Mon, 6 Nov 2017 15:02:14 GMT", "version": "v1" } ]
2018-02-14
[ [ "Zhou", "Zhi-Yong", "" ], [ "Xiao", "Zhiguang", "" ] ]
Recently, we have shown that the $X(3872)$ state can be naturally generated as a bound state by incorporating the hadron interactions into the Godfrey-Isgur quark model using the Friedrichs-like model combined with the QPC model, in which the wave function for the $X(3872)$ as a combination of the bare $c\bar c$ state and the continuum states can also be obtained. Under this scheme, we now investigate the isospin breaking effect of $X(3872)$ in its decays to $J/\psi\pi^+\pi^-$ and $J/\psi\pi^+\pi^-\pi^0$. By Considering its dominant continuum parts coupling to $J/\psi\rho$ and $J/\psi\omega$ through the quark rearrangement process, one could obtain the reasonable ratio of $\mathcal{B}(X(3872)\rightarrow J/\psi\pi^+\pi^-\pi^0)/\mathcal{B}(X(3872)\rightarrow J/\psi\pi^+\pi^-)\simeq (0.58\sim 0.92)$. It is also shown that the $\bar D D^*$ invariant mass distributions in the $B\rightarrow \bar D D^* K$ decays could be understood qualitatively at the same time. This scheme may provide more insight to understand the enigmatic nature of the $X(3872)$ state.
0905.1637
Daniel Gamermann
D. Gamermann, E. Oset, B. S. Zou
Testing the predicted dynamically generated hidden charm $X$ scalar state through the $D\bar D$ invariant mass spectrum and the radiative decay of the $\psi(3770)$
Proceedings for the International Workshop on Effective Field Theories: from the pion to the upsilon, February 2-6 2009, Valencia, Spain
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we present our model that dynamically generates resonances from charmed and light pseudoscalar and vector mesons. The model generates a rich spectrum of charmed and hidden charm scalar and axial resonances, most of them which can be associated with observed states. Other states are predicted, in particular a hidden charm scalar resonance with mass close to the $D\bar D$ threshold. For this resonance we present calculations which show that an observed enhancement in the $D\bar D$ mass spectrum measured by Belle in reactions producing $D\bar D J/\psi$ in the final state could be originated by this predicted state. We also present theoretical calculations on the radiative decay width of the $\psi(3770)$ into this state. The predicted branching fractions suggest that this predicted state could be observed by BES with statistics of one year run in the $\psi(3770)$ peak.
[ { "created": "Mon, 11 May 2009 15:25:55 GMT", "version": "v1" } ]
2009-05-12
[ [ "Gamermann", "D.", "" ], [ "Oset", "E.", "" ], [ "Zou", "B. S.", "" ] ]
In this work we present our model that dynamically generates resonances from charmed and light pseudoscalar and vector mesons. The model generates a rich spectrum of charmed and hidden charm scalar and axial resonances, most of them which can be associated with observed states. Other states are predicted, in particular a hidden charm scalar resonance with mass close to the $D\bar D$ threshold. For this resonance we present calculations which show that an observed enhancement in the $D\bar D$ mass spectrum measured by Belle in reactions producing $D\bar D J/\psi$ in the final state could be originated by this predicted state. We also present theoretical calculations on the radiative decay width of the $\psi(3770)$ into this state. The predicted branching fractions suggest that this predicted state could be observed by BES with statistics of one year run in the $\psi(3770)$ peak.
hep-ph/9306231
null
Yuji Koike
Octet Baryons at Finite Temperature: QCD Sum Rules vs. Chiral Symmetry
19 pages, MSUNSCL-870, LaTex files, 2 figs. consisting of simple Feynmann diagrams not included, Phys.Rev.D in press
Phys.Rev. D48 (1993) 2313-2323
10.1103/PhysRevD.48.2313
null
hep-ph nucl-th
null
Correlators of the octet baryons in the hot pion gas are studied in the framework of the QCD sum rule. The condensates appearing in the OPE side of the correlators become T-dependent through the interaction with thermal pions. We present an explicit demonstration that the $O(T^2)$-dependence of the condensates is completely compensated by the change of the pole residue and the $\pi + B \rightarrow B'$ scattering effect in the spectral functions. Therefore the baryon masses are constant to this order, although $\langle\bar{u}u\rangle_T\simeq\langle\bar{u}u\rangle_0(1-T^2/8f_\pi^2)$, which is consistent with the chiral symmetry constraint by Leutwyler and Smilga.
[ { "created": "Sat, 5 Jun 1993 23:58:03 GMT", "version": "v1" } ]
2009-10-22
[ [ "Koike", "Yuji", "" ] ]
Correlators of the octet baryons in the hot pion gas are studied in the framework of the QCD sum rule. The condensates appearing in the OPE side of the correlators become T-dependent through the interaction with thermal pions. We present an explicit demonstration that the $O(T^2)$-dependence of the condensates is completely compensated by the change of the pole residue and the $\pi + B \rightarrow B'$ scattering effect in the spectral functions. Therefore the baryon masses are constant to this order, although $\langle\bar{u}u\rangle_T\simeq\langle\bar{u}u\rangle_0(1-T^2/8f_\pi^2)$, which is consistent with the chiral symmetry constraint by Leutwyler and Smilga.
hep-ph/9710294
null
M.Arneodo, S.Maselli, C.Peroni
A Spectrometer to Study Elastic and Diffractive Physics at LHC
26 pages, 13 figures, Latex, submitted in International Journal of Modern Physics A
Int.J.Mod.Phys. A13 (1998) 3993-4010
10.1142/S0217751X98001864
null
hep-ph
null
The possibility to study elastic and diffractive physics in pp collisions at LHC is investigated. For this purpose we have considered detectors close to the beam in conjunction with the magnetic elements of the accelerator to provide a high precision spectrometer for very forward final state protons. The geometrical acceptance is given and momentum resolution is calculated for different spatial resolution detectors.
[ { "created": "Thu, 9 Oct 1997 13:09:20 GMT", "version": "v1" }, { "created": "Thu, 20 Nov 1997 11:15:51 GMT", "version": "v2" }, { "created": "Fri, 21 Nov 1997 15:10:14 GMT", "version": "v3" } ]
2009-10-30
[ [ "Arneodo", "M.", "" ], [ "Maselli", "S.", "" ], [ "Peroni", "C.", "" ] ]
The possibility to study elastic and diffractive physics in pp collisions at LHC is investigated. For this purpose we have considered detectors close to the beam in conjunction with the magnetic elements of the accelerator to provide a high precision spectrometer for very forward final state protons. The geometrical acceptance is given and momentum resolution is calculated for different spatial resolution detectors.
2212.14019
Marat Siddikov Ilfatovich
Marat Siddikov, Ivan Schmidt
Exclusive production of quarkonia pairs in collinear factorization framework
26 pages, 11 figures
null
10.1103/PhysRevD.107.034037
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we analyze the exclusive photoproduction of heavy quarkonia pairs in the collinear factorization framework. We evaluate the amplitude of the process for $J/\psi\,-\eta_{c}$ quarkonia pair in the leading order of the strong coupling $\alpha_{s},$ and express it in terms of generalized parton distributions (GPDs) of gluons in the proton. We made numerical estimates in the kinematics of the Electron Ion Collider, and found that in the photoproduction regime, when the virtuality of the photon is much smaller than the quarkonia mass, the cross-section of the process is sufficiently large for experimental studies. We demonstrate that the study of this channel can complement existing studies of gluon GPDs from other channels.
[ { "created": "Wed, 28 Dec 2022 18:44:53 GMT", "version": "v1" }, { "created": "Tue, 31 Jan 2023 01:24:02 GMT", "version": "v2" } ]
2023-03-15
[ [ "Siddikov", "Marat", "" ], [ "Schmidt", "Ivan", "" ] ]
In this paper we analyze the exclusive photoproduction of heavy quarkonia pairs in the collinear factorization framework. We evaluate the amplitude of the process for $J/\psi\,-\eta_{c}$ quarkonia pair in the leading order of the strong coupling $\alpha_{s},$ and express it in terms of generalized parton distributions (GPDs) of gluons in the proton. We made numerical estimates in the kinematics of the Electron Ion Collider, and found that in the photoproduction regime, when the virtuality of the photon is much smaller than the quarkonia mass, the cross-section of the process is sufficiently large for experimental studies. We demonstrate that the study of this channel can complement existing studies of gluon GPDs from other channels.
1912.13001
Hua-Sheng Shao
Long-Bin Chen, Hai Tao Li, Hua-Sheng Shao and Jian Wang
The gluon-fusion production of Higgs boson pair: N$^3$LO QCD corrections and top-quark mass effects
51 pages, 23 figures, 4 tables. v2: journal version (minor corrections wrt v1)
JHEP 03 (2020) 072
10.1007/JHEP03(2020)072
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Higgs boson pair production via gluon fusion at high-energy hadron colliders, such as the LHC, is vital in deciphering the Higgs potential and in pinning down the electroweak symmetry breaking mechanism. We carry out the next-to-next-to-next-to-leading order (N$^3$LO) QCD calculations in the infinite top-quark mass limit and present predictions for both the inclusive and differential cross sections, albeit the differential distributions other than the invariant mass distribution of the Higgs boson pair are approximated at N$^3$LO. Such corrections are indispensable in stabilising the perturbative expansion of the cross section in the strong coupling $\alpha_s$. At the inclusive level, the scale uncertainties are reduced by a factor of four compared with the next-to-next-to-leading order (NNLO) results. Given that the inclusion of the top-quark mass effects is essential for the phenomenological applications, we use several schemes to incorporate the N$^3$LO results in the infinite top-quark mass limit and the next-to-leading order (NLO) results with full top-quark mass dependence, and present theoretical predictions for the (differential) cross sections in the proton-proton collisions at the centre-of-mass energies $\sqrt{s}=13,14,27$ and $100$ TeV. Our results provide one of the most precise theoretical inputs for the analyses of the Higgs boson pair events.
[ { "created": "Mon, 30 Dec 2019 16:50:36 GMT", "version": "v1" }, { "created": "Fri, 13 Mar 2020 06:44:39 GMT", "version": "v2" } ]
2020-03-16
[ [ "Chen", "Long-Bin", "" ], [ "Li", "Hai Tao", "" ], [ "Shao", "Hua-Sheng", "" ], [ "Wang", "Jian", "" ] ]
The Higgs boson pair production via gluon fusion at high-energy hadron colliders, such as the LHC, is vital in deciphering the Higgs potential and in pinning down the electroweak symmetry breaking mechanism. We carry out the next-to-next-to-next-to-leading order (N$^3$LO) QCD calculations in the infinite top-quark mass limit and present predictions for both the inclusive and differential cross sections, albeit the differential distributions other than the invariant mass distribution of the Higgs boson pair are approximated at N$^3$LO. Such corrections are indispensable in stabilising the perturbative expansion of the cross section in the strong coupling $\alpha_s$. At the inclusive level, the scale uncertainties are reduced by a factor of four compared with the next-to-next-to-leading order (NNLO) results. Given that the inclusion of the top-quark mass effects is essential for the phenomenological applications, we use several schemes to incorporate the N$^3$LO results in the infinite top-quark mass limit and the next-to-leading order (NLO) results with full top-quark mass dependence, and present theoretical predictions for the (differential) cross sections in the proton-proton collisions at the centre-of-mass energies $\sqrt{s}=13,14,27$ and $100$ TeV. Our results provide one of the most precise theoretical inputs for the analyses of the Higgs boson pair events.
0708.2466
Junegone Chay
Junegone Chay, Chul Kim, Adam K. Leibovich and Jure Zupan
Probing electroweak physics using B -> XM decays in the endpoint region
27 pages, 6 figures
Phys.Rev.D76:094031,2007
10.1103/PhysRevD.76.094031
null
hep-ph
null
Using soft-collinear effective theory we describe at leading order in 1/m_b all the semi-inclusive hadronic B -> XM decays near the endpoint, where an energetic light meson M recoils against an inclusive jet X. We also include the decays involving eta, eta' mesons that receive additional contributions from gluonic operators. The predicted branching ratios and CP asymmetries depend on fewer hadronic parameters than the corresponding two-body B decays. This makes semi-inclusive hadronic B -> XM decays a powerful probe of the potential nonperturbative nature of charming penguins as well as a useful probe of new physics effects in electroweak flavor changing transitions. A comparison with B -> KX data from BaBar points to an enhanced charming penguin, albeit with large experimental errors.
[ { "created": "Sat, 18 Aug 2007 06:02:33 GMT", "version": "v1" } ]
2008-11-26
[ [ "Chay", "Junegone", "" ], [ "Kim", "Chul", "" ], [ "Leibovich", "Adam K.", "" ], [ "Zupan", "Jure", "" ] ]
Using soft-collinear effective theory we describe at leading order in 1/m_b all the semi-inclusive hadronic B -> XM decays near the endpoint, where an energetic light meson M recoils against an inclusive jet X. We also include the decays involving eta, eta' mesons that receive additional contributions from gluonic operators. The predicted branching ratios and CP asymmetries depend on fewer hadronic parameters than the corresponding two-body B decays. This makes semi-inclusive hadronic B -> XM decays a powerful probe of the potential nonperturbative nature of charming penguins as well as a useful probe of new physics effects in electroweak flavor changing transitions. A comparison with B -> KX data from BaBar points to an enhanced charming penguin, albeit with large experimental errors.
hep-ph/0110075
John Ralston
John P. Ralston and Bernard Pire
Femto-Photography of Protons to Nuclei with Deeply Virtual Compton Scattering
To be published in Physical Review D. Replaces previous version with minor changes in presentation
Phys.Rev.D66:111501,2002
10.1103/PhysRevD.66.111501
CPHT-S038-0901
hep-ph nucl-th
null
Developments in deeply virtual Compton scattering allow the direct measurements of scattering amplitudes for exchange of a highly virtual photon with fine spatial resolution. Real-space images of the target can be obtained from this information. Spatial resolution is determined by the momentum transfer rather than the wavelength of the detected photon. Quantum photographs of the proton, nuclei, and other elementary particles with resolution on the scale of a fraction of a femtometer is feasible with existing experimental technology.
[ { "created": "Thu, 4 Oct 2001 19:56:02 GMT", "version": "v1" }, { "created": "Wed, 20 Nov 2002 23:48:22 GMT", "version": "v2" } ]
2014-11-17
[ [ "Ralston", "John P.", "" ], [ "Pire", "Bernard", "" ] ]
Developments in deeply virtual Compton scattering allow the direct measurements of scattering amplitudes for exchange of a highly virtual photon with fine spatial resolution. Real-space images of the target can be obtained from this information. Spatial resolution is determined by the momentum transfer rather than the wavelength of the detected photon. Quantum photographs of the proton, nuclei, and other elementary particles with resolution on the scale of a fraction of a femtometer is feasible with existing experimental technology.
hep-ph/9906208
Bob Holdom
B. Holdom and T. Torma
New physics in ttbar spin correlations at the Tevatron
13 pages, 3 figures, two references added and cosmetic changes
Phys.Rev.D60:114010,1999
10.1103/PhysRevD.60.114010
UTPT-99-06
hep-ph
null
We show that the angular distributions of leptons or jets due to ttbar spin correlations allow a determination of the top chromomagnetic moment kappa with an accuracy of order 0.1. The method is quite insensitive to background, event reconstruction, and other experimental uncertainties. The total event number is important, so we suggest the inclusion of all-hadronic events.
[ { "created": "Tue, 1 Jun 1999 16:26:36 GMT", "version": "v1" }, { "created": "Thu, 3 Jun 1999 16:47:34 GMT", "version": "v2" } ]
2011-03-23
[ [ "Holdom", "B.", "" ], [ "Torma", "T.", "" ] ]
We show that the angular distributions of leptons or jets due to ttbar spin correlations allow a determination of the top chromomagnetic moment kappa with an accuracy of order 0.1. The method is quite insensitive to background, event reconstruction, and other experimental uncertainties. The total event number is important, so we suggest the inclusion of all-hadronic events.
0704.3481
Masafumi Kurachi
Masafumi Kurachi, Robert Shrock, Koichi Yamawaki
Z Boson Propagator Correction in Technicolor Theories with ETC Effects Included
15pages, 8 figures
Phys.Rev.D76:035003,2007
10.1103/PhysRevD.76.035003
YITP-SB-07-07
hep-ph
null
We calculate the Z boson propagator correction, as described by the S parameter, in technicolor theories with extended technicolor interactions included. Our method is to solve the Bethe-Salpeter equation for the requisite current-current correlation functions. Our results suggest that the inclusion of extended technicolor interactions has a relatively small effect on S.
[ { "created": "Thu, 26 Apr 2007 07:06:41 GMT", "version": "v1" } ]
2008-11-26
[ [ "Kurachi", "Masafumi", "" ], [ "Shrock", "Robert", "" ], [ "Yamawaki", "Koichi", "" ] ]
We calculate the Z boson propagator correction, as described by the S parameter, in technicolor theories with extended technicolor interactions included. Our method is to solve the Bethe-Salpeter equation for the requisite current-current correlation functions. Our results suggest that the inclusion of extended technicolor interactions has a relatively small effect on S.
hep-ph/0004064
Hans-Peter Nilles
Hans Peter Nilles
On the low-energy limit of string and M-theory
For those that asked for a copy: TASI97 lectures as published in Supersymmetry, Supergravity and Supercolliders, World Scientific, Ed. J. A. Bagger
null
null
null
hep-ph
null
We discuss the possible applications of string theory for the construction of generalizations of the $SU(3)\times SU(2)\times U(1)$ standard model of strong and electroweak interactions. This includes an investigation of effective $d=4$ dimensional supergravity theories that could be derived from higher dimensional string theories ($d=10$) and M-theory ($d=11$).It is shown how the question of unification of gauge and gravitational coupling constants could find a solution within this framework. The mechanism of hidden sector supersymmetry breakdown and its consequences for the pattern for soft supersymmetry breaking terms are discussed in detail.
[ { "created": "Fri, 7 Apr 2000 09:45:59 GMT", "version": "v1" } ]
2007-05-23
[ [ "Nilles", "Hans Peter", "" ] ]
We discuss the possible applications of string theory for the construction of generalizations of the $SU(3)\times SU(2)\times U(1)$ standard model of strong and electroweak interactions. This includes an investigation of effective $d=4$ dimensional supergravity theories that could be derived from higher dimensional string theories ($d=10$) and M-theory ($d=11$).It is shown how the question of unification of gauge and gravitational coupling constants could find a solution within this framework. The mechanism of hidden sector supersymmetry breakdown and its consequences for the pattern for soft supersymmetry breaking terms are discussed in detail.
2205.07224
Hui-Min Yang
Hui-Min Yang, Hua-Xing Chen, Er-Liang Cui, Qiang Mao
Identifying the $\Xi_b(6100)$ as the $P$-wave bottom baryon of $J^P=3/2^-$
13 pages, 2 figures, 4 tables, suggestions and comments welcome. arXiv admin note: text overlap with arXiv:2106.15488
null
10.1103/PhysRevD.106.036018
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We study the $\Xi_b(6100)$ using the methods of QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory. Our results suggest that the $\Xi_b(6100)$ can be well interpreted as the $P$-wave bottom baryon of $J^P=3/2^-$, belonging to the $SU(3)$ flavor $\mathbf{\bar 3}_F$ representation. It has a partner state of $J^P=1/2^-$, labelled as $\Xi_b(1/2^-)$, whose mass and width are predicted to be $m_{\Xi_b(1/2^-)}=6.08^{+0.13}_{-0.11}$~GeV and $\Gamma_{\Xi_b(1/2^-)}=4^{+29}_{-~4}$~MeV, with the mass splitting $\Delta M=m_{\Xi_b(6100)}-m_{\Xi_b(1/2^-)}=9\pm3$~MeV. We propose to search for it in the $\Xi_c({1/2}^-)\to \Xi_b^{\prime}\pi$ decay channel. Our results also suggest that the $\Lambda_b(5912)$ and $\Lambda_b(5920)$ are their partner states with $J^P=1/2^-$ and $3/2^-$ respectively, and moreover, the $\Lambda_c(2595)$, $\Lambda_c(2625)$, $\Xi_c(2790)$, and $\Xi_c(2815)$ are their charmed partner states.
[ { "created": "Sun, 15 May 2022 08:57:58 GMT", "version": "v1" }, { "created": "Fri, 12 Aug 2022 08:54:07 GMT", "version": "v2" } ]
2022-08-31
[ [ "Yang", "Hui-Min", "" ], [ "Chen", "Hua-Xing", "" ], [ "Cui", "Er-Liang", "" ], [ "Mao", "Qiang", "" ] ]
We study the $\Xi_b(6100)$ using the methods of QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory. Our results suggest that the $\Xi_b(6100)$ can be well interpreted as the $P$-wave bottom baryon of $J^P=3/2^-$, belonging to the $SU(3)$ flavor $\mathbf{\bar 3}_F$ representation. It has a partner state of $J^P=1/2^-$, labelled as $\Xi_b(1/2^-)$, whose mass and width are predicted to be $m_{\Xi_b(1/2^-)}=6.08^{+0.13}_{-0.11}$~GeV and $\Gamma_{\Xi_b(1/2^-)}=4^{+29}_{-~4}$~MeV, with the mass splitting $\Delta M=m_{\Xi_b(6100)}-m_{\Xi_b(1/2^-)}=9\pm3$~MeV. We propose to search for it in the $\Xi_c({1/2}^-)\to \Xi_b^{\prime}\pi$ decay channel. Our results also suggest that the $\Lambda_b(5912)$ and $\Lambda_b(5920)$ are their partner states with $J^P=1/2^-$ and $3/2^-$ respectively, and moreover, the $\Lambda_c(2595)$, $\Lambda_c(2625)$, $\Xi_c(2790)$, and $\Xi_c(2815)$ are their charmed partner states.
1207.7236
Martin Spinrath
Stefan Antusch, Lorenzo Calibbi, Vinzenz Maurer, Maurizio Monaco, Martin Spinrath
Naturalness of the Non-Universal MSSM in the light of the recent Higgs results
24 pages, 8 figures; version accepted for publication in JHEP
JHEP 01 (2013) 187
10.1007/JHEP01(2013)187
MPP-2012-120; SISSA 22/2012/EP
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyse the naturalness of the Minimal Supersymmetric Standard Model (MSSM) in the light of recent LHC results from the ATLAS and CMS experiments. We study non-universal boundary conditions for the scalar and the gaugino sector, with fixed relations between some of the soft breaking parameters, and find a significant reduction of fine-tuning for non-universal gaugino masses. For a Higgs mass of about 125 GeV, as observed recently, we find parameter regions with a fine-tuning of O(10), taking into account experimental and theoretical uncertainties. These regions also survive after comparison with simplified model searches in ATLAS and CMS. For a fine-tuning less than 20 the lightest neutralino is expected to be lighter than about 400 GeV and the lighter stop can be as heavy as 3.5 TeV. On the other hand, the gluino mass is required to be above 1.5 TeV. For non-universal gaugino masses, we discuss which fixed GUT scale ratios can lead to a reduced fine-tuning and find that the recent Higgs results have a strong impact on which ratio is favoured. We also discuss the naturalness of GUT scale Yukawa relations, comparing the non-universal MSSM with the CMSSM.
[ { "created": "Tue, 31 Jul 2012 13:31:58 GMT", "version": "v1" }, { "created": "Wed, 30 Jan 2013 13:49:46 GMT", "version": "v2" } ]
2013-02-07
[ [ "Antusch", "Stefan", "" ], [ "Calibbi", "Lorenzo", "" ], [ "Maurer", "Vinzenz", "" ], [ "Monaco", "Maurizio", "" ], [ "Spinrath", "Martin", "" ] ]
We analyse the naturalness of the Minimal Supersymmetric Standard Model (MSSM) in the light of recent LHC results from the ATLAS and CMS experiments. We study non-universal boundary conditions for the scalar and the gaugino sector, with fixed relations between some of the soft breaking parameters, and find a significant reduction of fine-tuning for non-universal gaugino masses. For a Higgs mass of about 125 GeV, as observed recently, we find parameter regions with a fine-tuning of O(10), taking into account experimental and theoretical uncertainties. These regions also survive after comparison with simplified model searches in ATLAS and CMS. For a fine-tuning less than 20 the lightest neutralino is expected to be lighter than about 400 GeV and the lighter stop can be as heavy as 3.5 TeV. On the other hand, the gluino mass is required to be above 1.5 TeV. For non-universal gaugino masses, we discuss which fixed GUT scale ratios can lead to a reduced fine-tuning and find that the recent Higgs results have a strong impact on which ratio is favoured. We also discuss the naturalness of GUT scale Yukawa relations, comparing the non-universal MSSM with the CMSSM.
hep-ph/9408368
Andres Schaale
A.A.Bel'kov, A.V.Lanyov, A.Schaale, S.Scherer
An Effective Chiral Meson Lagrangian at $O(P^6)$ from the NJL Model
20 pages
Acta Phys.Slov. 45 (1995) 121
null
null
hep-ph
null
In this work we present a strong chiral meson Lagrangian up to and including $O(p^6)$ in the momentum expansion. It is derived from the Nambu--Jona-Lasinio (NJL) model using the heat-kernel method. Identities related to the properties of covariant derivatives of the chiral matrix $U$ as well as field transformations have been used to obtain a minimal set of linearly independent terms.
[ { "created": "Thu, 25 Aug 1994 18:57:39 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bel'kov", "A. A.", "" ], [ "Lanyov", "A. V.", "" ], [ "Schaale", "A.", "" ], [ "Scherer", "S.", "" ] ]
In this work we present a strong chiral meson Lagrangian up to and including $O(p^6)$ in the momentum expansion. It is derived from the Nambu--Jona-Lasinio (NJL) model using the heat-kernel method. Identities related to the properties of covariant derivatives of the chiral matrix $U$ as well as field transformations have been used to obtain a minimal set of linearly independent terms.
hep-ph/0212045
Daniel Bartz
D. Bartz
Scalar and Tensor Force Contribution to the Nucleon-Nucleon Interaction Within a Chiral Constituent Quark Model
6 pages (LaTeX with aip-6s.clo, aipproc.cls and aipxfm.sty packages), 2 eps figures. Presented at the II International Workshop on Hadron Physics, 25-29 September, 2002, Coimbra, Portugal
AIP Conf.Proc. 660 (2003) 383-388
10.1063/1.1570588
null
hep-ph
null
The nucleon-nucleon problem is studied as a six-quark system in a nonrelativistic chiral constituent quark model where the Hamiltonian contains a linear confinement and a pseudoscalar meson (Goldstone boson) exchange interaction between the quarks. This hyperfine interaction has a long-range Yukawa-type part, depending on the mass of the exchanged meson and a short-range part, mainly responsible for the good description of the baryon spectra.
[ { "created": "Tue, 3 Dec 2002 13:24:30 GMT", "version": "v1" } ]
2009-11-07
[ [ "Bartz", "D.", "" ] ]
The nucleon-nucleon problem is studied as a six-quark system in a nonrelativistic chiral constituent quark model where the Hamiltonian contains a linear confinement and a pseudoscalar meson (Goldstone boson) exchange interaction between the quarks. This hyperfine interaction has a long-range Yukawa-type part, depending on the mass of the exchanged meson and a short-range part, mainly responsible for the good description of the baryon spectra.
hep-ph/9811477
null
M. Czakon, J. Gluza, M. Zralek (University of Silesia)
Majorana neutrino transition magnetic moments in left-right symmetric models
4 pages. Presented at the ICHEP Conference, Vancouver, 1998. To appear in Proceedings
Phys.Rev. D59 (1999) 013010
10.1103/PhysRevD.59.013010
null
hep-ph
null
Transition magnetic moments of Majorana neutrinos are discussed in the frame of the most natural version of the LR model (with left- and right-handed triplets and a bidoublet in the Higgs sector). We show that their largest values could be at most $6\cdot 10^{-13} \mu_B$ from diagrams with $W_L$ in the loop. This could happen for specific models where (i) neutrino-charged lepton mixing is maximal and (ii) $\kappa_1 \simeq \kappa_2$ (VEVs for neutral Higgs fields in the bidoublet $\phi$ are equal). Contributions from diagrams with charged Higgses in the loop are smaller than those in the SM with right-handed neutrinos.
[ { "created": "Thu, 26 Nov 1998 13:11:04 GMT", "version": "v1" } ]
2009-10-31
[ [ "Czakon", "M.", "", "University of Silesia" ], [ "Gluza", "J.", "", "University of Silesia" ], [ "Zralek", "M.", "", "University of Silesia" ] ]
Transition magnetic moments of Majorana neutrinos are discussed in the frame of the most natural version of the LR model (with left- and right-handed triplets and a bidoublet in the Higgs sector). We show that their largest values could be at most $6\cdot 10^{-13} \mu_B$ from diagrams with $W_L$ in the loop. This could happen for specific models where (i) neutrino-charged lepton mixing is maximal and (ii) $\kappa_1 \simeq \kappa_2$ (VEVs for neutral Higgs fields in the bidoublet $\phi$ are equal). Contributions from diagrams with charged Higgses in the loop are smaller than those in the SM with right-handed neutrinos.
hep-ph/9902368
Tracas Nicholas
G.K. Leontaris and N.D. Tracas
String Unification at Intermediate Energies: Phenomenological Viability and Implications
11 pages, 2 figure included in the ps file, uses psfig.sty
Phys.Lett. B454 (1999) 53-58
10.1016/S0370-2693(99)00384-6
IOA-TH/99-10, NTUA-05/99
hep-ph
null
Motivated by the fact that the string scale can be many orders of magnitude lower than the Planck mass, we investigate the required modifications in the MSSM $\beta$--functions in order to achieve intermediate ($10^{10-13}$GeV) scale unification, keeping the traditional logarithmic running of the gauge couplings. We present examples of string unified models with the required extra matter for such a unification while we also check whether other MSSM properties (such as radiative symmetry breaking) are still applicable.
[ { "created": "Tue, 16 Feb 1999 19:20:52 GMT", "version": "v1" } ]
2009-10-31
[ [ "Leontaris", "G. K.", "" ], [ "Tracas", "N. D.", "" ] ]
Motivated by the fact that the string scale can be many orders of magnitude lower than the Planck mass, we investigate the required modifications in the MSSM $\beta$--functions in order to achieve intermediate ($10^{10-13}$GeV) scale unification, keeping the traditional logarithmic running of the gauge couplings. We present examples of string unified models with the required extra matter for such a unification while we also check whether other MSSM properties (such as radiative symmetry breaking) are still applicable.
hep-ph/0103104
Luigi Pilo
R. Contino, L. Pilo, R. Rattazzi and A. Strumia
Graviton loops and brane observables
9 pages + 4 eps figures, JHEP style latex document. The paper is composed by a theoretical part, followed (after page 21) by a phenomenological part. v2: version published in JHEP, few typos corrected. v3: few additional typos corrected in the Appendix
JHEP 0106:005,2001
10.1088/1126-6708/2001/06/005
CERN-TH/2000-383, IFUP-TH/2000-24, SNS-PH/01-04
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss how to consistently perform effective Lagrangian computations in quantum gravity with branes in compact extra dimensions. A reparametrization invariant and infrared finite result is obtained in a non trivial way. It is crucial to properly account for brane fluctuations and to correctly identify physical observables. Our results correct some confusing claims in the literature. We discuss the implications of graviton loops on electroweak precision observables and on the muon g-2 in models with large extra dimensions. We model the leading effects, not controlled by effective field theory, by introducing a hard momentum cut-off.
[ { "created": "Sat, 10 Mar 2001 10:39:12 GMT", "version": "v1" }, { "created": "Wed, 4 Jul 2001 11:01:36 GMT", "version": "v2" }, { "created": "Fri, 14 Mar 2014 13:48:55 GMT", "version": "v3" } ]
2014-03-17
[ [ "Contino", "R.", "" ], [ "Pilo", "L.", "" ], [ "Rattazzi", "R.", "" ], [ "Strumia", "A.", "" ] ]
We discuss how to consistently perform effective Lagrangian computations in quantum gravity with branes in compact extra dimensions. A reparametrization invariant and infrared finite result is obtained in a non trivial way. It is crucial to properly account for brane fluctuations and to correctly identify physical observables. Our results correct some confusing claims in the literature. We discuss the implications of graviton loops on electroweak precision observables and on the muon g-2 in models with large extra dimensions. We model the leading effects, not controlled by effective field theory, by introducing a hard momentum cut-off.
2108.10625
Chao Shi
Chao Shi, Ming Li, Xurong Chen and Wenbao Jia
Ground state pseudoscalar mesons on the light front: from the light to heavy sector
10 pages, 9 figures
null
10.1103/PhysRevD.104.094016
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extract the leading Fock-state light front wave functions (LF-LFWFs) of both the light and heavy pseudoscalar mesons, e.g., the pion (at masses of 130 MeV, 310 MeV and 690 MeV), $\eta_c$ and $\eta_b$, from their covariant Bethe-Salpeter wave functions within the rainbow-ladder (RL) truncation. It is shown that the LF-LFWFs get narrower in $x$ (the longitudinal momentum fraction of meson carried by the quark) with the increasing current quark mass, and the leading twist parton distribution amplitudes (PDAs) inherit this feature. Meanwhile, we find in the pion the LF-LFWFs only contribute around 30\% to the total Fock-state normalization, indicating the presence of significant higher Fock-states within. In contrast, in the $\eta_c$ and $\eta_b$ the LF-LFWFs contribute more than $90$\%, suggesting the $Q\bar{Q}$ valence Fock-state truncation as a good approximation for heavy mesons. We thus study the 3-dimensional parton distributions of the $\eta_c$ and $\eta_b$ with the unpolarized generalized parton distribution function (GPD) and the transverse momentum dependent parton distribution function (TMD). Through the gravitational form factors in connection with the GPD, the mass radii of the $\eta_c$ and $\eta_b$ in the light-cone frame are determined to be $r_{E,{\rm LC}}^{\eta_c} =0.150$ fm and $r_{E,{\rm LC}}^{\eta_b} =0.089$ fm respectively.
[ { "created": "Tue, 24 Aug 2021 10:24:24 GMT", "version": "v1" } ]
2021-11-24
[ [ "Shi", "Chao", "" ], [ "Li", "Ming", "" ], [ "Chen", "Xurong", "" ], [ "Jia", "Wenbao", "" ] ]
We extract the leading Fock-state light front wave functions (LF-LFWFs) of both the light and heavy pseudoscalar mesons, e.g., the pion (at masses of 130 MeV, 310 MeV and 690 MeV), $\eta_c$ and $\eta_b$, from their covariant Bethe-Salpeter wave functions within the rainbow-ladder (RL) truncation. It is shown that the LF-LFWFs get narrower in $x$ (the longitudinal momentum fraction of meson carried by the quark) with the increasing current quark mass, and the leading twist parton distribution amplitudes (PDAs) inherit this feature. Meanwhile, we find in the pion the LF-LFWFs only contribute around 30\% to the total Fock-state normalization, indicating the presence of significant higher Fock-states within. In contrast, in the $\eta_c$ and $\eta_b$ the LF-LFWFs contribute more than $90$\%, suggesting the $Q\bar{Q}$ valence Fock-state truncation as a good approximation for heavy mesons. We thus study the 3-dimensional parton distributions of the $\eta_c$ and $\eta_b$ with the unpolarized generalized parton distribution function (GPD) and the transverse momentum dependent parton distribution function (TMD). Through the gravitational form factors in connection with the GPD, the mass radii of the $\eta_c$ and $\eta_b$ in the light-cone frame are determined to be $r_{E,{\rm LC}}^{\eta_c} =0.150$ fm and $r_{E,{\rm LC}}^{\eta_b} =0.089$ fm respectively.
hep-ph/9405252
Annemarie Blobel
Ralf Hempfling
On the fine-tuning problem in minimal SO(10) SUSY-GUT
20 pages, 10 figs, uses PHYZZX version to be published in Phys Rev. D
Phys.Rev.D52:4106-4115,1995
10.1103/PhysRevD.52.4106
DESY 94-078 and MPI-PTh 95-53
hep-ph
null
In grand unified theories (GUT) based on SO(10) all fermions of one generation are embedded in a single representation. As a result, the top quark, the bottom quark, and the $\tau$ lepton have a universal Yukawa coupling at the GUT scale. This implies a very large ratio of Higgs vacuum expectation values, $\tanb \simeq m_t/m_b$. We analyze the naturalness of such a scenario quantitatively including all the relevant radiative corrections and find that in minimal unified supergravity models with universal soft supersymmetry breaking parameters at the GUT scale, the necessary amount of fine-tuning needed is excessive. GUT threshold correction to the universal Higgs mass parameter can significantly reduce the fine-tuning required for such large values of $\tanb$. We also point out that the top quark mass can play a crucial role in explaining the hierarchy between the SUSY breaking scale and the electro-weak scale and, hence, the naturalness of large values of $\tanb$.
[ { "created": "Mon, 9 May 1994 12:52:55 GMT", "version": "v1" }, { "created": "Mon, 19 Jun 1995 10:53:36 GMT", "version": "v2" } ]
2011-07-19
[ [ "Hempfling", "Ralf", "" ] ]
In grand unified theories (GUT) based on SO(10) all fermions of one generation are embedded in a single representation. As a result, the top quark, the bottom quark, and the $\tau$ lepton have a universal Yukawa coupling at the GUT scale. This implies a very large ratio of Higgs vacuum expectation values, $\tanb \simeq m_t/m_b$. We analyze the naturalness of such a scenario quantitatively including all the relevant radiative corrections and find that in minimal unified supergravity models with universal soft supersymmetry breaking parameters at the GUT scale, the necessary amount of fine-tuning needed is excessive. GUT threshold correction to the universal Higgs mass parameter can significantly reduce the fine-tuning required for such large values of $\tanb$. We also point out that the top quark mass can play a crucial role in explaining the hierarchy between the SUSY breaking scale and the electro-weak scale and, hence, the naturalness of large values of $\tanb$.
hep-ph/9601353
Leonid Glozman
L.Ya. Glozman, Z. Papp, W. Plessas
Light Baryons in a Constituent Quark Model with Chiral Dynamics
12 pages, submitted to Phys. Lett. B
Phys.Lett. B381 (1996) 311-316
10.1016/0370-2693(96)00610-7
UNIGRAZ-UTP 27-01-96
hep-ph nucl-th
null
It is shown from rigorous three-body Faddeev calculations that the masses of all 14 lowest states in the $N$ and $\Delta$ spectra can be described within a constituent quark model with a Goldstone-boson-exchange interaction plus linear confinement between the constituent quarks.
[ { "created": "Mon, 29 Jan 1996 13:30:51 GMT", "version": "v1" } ]
2009-10-28
[ [ "Glozman", "L. Ya.", "" ], [ "Papp", "Z.", "" ], [ "Plessas", "W.", "" ] ]
It is shown from rigorous three-body Faddeev calculations that the masses of all 14 lowest states in the $N$ and $\Delta$ spectra can be described within a constituent quark model with a Goldstone-boson-exchange interaction plus linear confinement between the constituent quarks.
1909.04887
Khushboo Dixit
Khushboo Dixit, Ashutosh Kumar Alok
New physics effects on quantum coherence in neutrino oscillations
8 pages, 2 figures; Matches published version
Eur. Phys. J. Plus (2021) 136:334
10.1140/epjp/s13360-021-01311-4
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Several measures of quantum correlations such as Leggett-Garg and Bell-type inequalities have been extensively studied in the context of neutrino oscillations. However these analyses are performed under the assumption of standard model (SM) interactions of neutrinos. In this work we study new physics effects on $l_1$-norm based measure of quantum coherence which quantifies the quantumness embedded in the system and is also intrinsically related to various measures of quantum correlations. Moreover, it is considered to be a resource theoretical tool which can be utilized in quantum algorithms and quantum channel discrimination. The new physics effects are incorporated in a model independent way by using the effective Lagrangian for the neutral current non-standard neutrino interactions (NSI). Bounds on the NSI parameters are extracted from a recent global analysis of oscillation experiments including COHERENT (coherent neutrino-nucleus scattering experiment) data. In the context of upcoming DUNE experimental setup, we find that the most favourable combination of LMA-Light sector of $\theta_{12}$ (i.e., $\theta_{12}< 45^o$) with normal mass ordering decreases the coherence in the system in comparison to the SM prediction for all values of neutrino energy E and CP violating phase $\delta$ (except in the narrow region around E ~ 2 GeV). On the other hand, a large enhancement in the value of coherence parameter in the entire $(E-\delta)$ plane is possible for the dark octant of $\theta_{12}$ ($\theta_{12}> 45^o$) with inverted ordering. For almost all values of CP violating phase, the enhancement is more protuberant in the region around E ~ 4 GeV where maximum neutrino flux is expected in the DUNE experiment. Therefore for the normal mass ordering, the SM interaction provides favourable conditions for quantum information tasks while the NSI favours inverted ordering scenario for such tasks.
[ { "created": "Wed, 11 Sep 2019 07:40:31 GMT", "version": "v1" }, { "created": "Thu, 25 Mar 2021 20:18:24 GMT", "version": "v2" } ]
2021-03-29
[ [ "Dixit", "Khushboo", "" ], [ "Alok", "Ashutosh Kumar", "" ] ]
Several measures of quantum correlations such as Leggett-Garg and Bell-type inequalities have been extensively studied in the context of neutrino oscillations. However these analyses are performed under the assumption of standard model (SM) interactions of neutrinos. In this work we study new physics effects on $l_1$-norm based measure of quantum coherence which quantifies the quantumness embedded in the system and is also intrinsically related to various measures of quantum correlations. Moreover, it is considered to be a resource theoretical tool which can be utilized in quantum algorithms and quantum channel discrimination. The new physics effects are incorporated in a model independent way by using the effective Lagrangian for the neutral current non-standard neutrino interactions (NSI). Bounds on the NSI parameters are extracted from a recent global analysis of oscillation experiments including COHERENT (coherent neutrino-nucleus scattering experiment) data. In the context of upcoming DUNE experimental setup, we find that the most favourable combination of LMA-Light sector of $\theta_{12}$ (i.e., $\theta_{12}< 45^o$) with normal mass ordering decreases the coherence in the system in comparison to the SM prediction for all values of neutrino energy E and CP violating phase $\delta$ (except in the narrow region around E ~ 2 GeV). On the other hand, a large enhancement in the value of coherence parameter in the entire $(E-\delta)$ plane is possible for the dark octant of $\theta_{12}$ ($\theta_{12}> 45^o$) with inverted ordering. For almost all values of CP violating phase, the enhancement is more protuberant in the region around E ~ 4 GeV where maximum neutrino flux is expected in the DUNE experiment. Therefore for the normal mass ordering, the SM interaction provides favourable conditions for quantum information tasks while the NSI favours inverted ordering scenario for such tasks.
0912.0940
Yoshimasa Hidaka
Yoshimasa Hidaka and Robert D. Pisarski
Small shear viscosity in the semi quark gluon plasma
45 pages, 8 figures, REVTeX; Abstract and Sec. III.A modified to clarify the physical discussion.
Phys.Rev.D81:076002,2010
10.1103/PhysRevD.81.076002
KUNS-2242, BNL-90640-2009-JA
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
At nonzero temperature in QCD, about the deconfining phase transition there is a "semi" quark gluon plasma (semi-QGP), where the expectation value of the (renormalized) Polyakov loop is less than one. This can be modeled by a semiclassical expansion about a constant field for the vector potential, A_0, which is diagonal in color. We compute the shear viscosity in the semi-QGP by using the Boltzmann equation in the presence of this background field. To leading, logarithmic order in weak coupling, the dominant diagrams are given by the usual scattering processes of 2 -> 2 particles. For simplicity we also assume that both the number of colors and flavors are large. Near the critical temperature T_c, where the expectation value of the Polyakov loop is small, the overall density of colored fields decreases according to their color representation, with the density of quarks vanishes linearly with the loop, and that of gluons, quadratically. This decrease in the overall density dominates changes in the transport cross section. As a result, relative to that in the perturbative QGP, near T_c the shear viscosity in the semi-QGP is suppressed by two powers of the Polyakov loop. In a semiclassical expansion, the suppression of colored fields depends only upon which color representation they lie in, and not upon their mass. That light and heavy quarks are suppressed in a common manner may help to explain the behavior of charm quarks at RHIC.
[ { "created": "Fri, 4 Dec 2009 21:00:59 GMT", "version": "v1" }, { "created": "Sun, 25 Apr 2010 17:23:37 GMT", "version": "v2" } ]
2010-04-28
[ [ "Hidaka", "Yoshimasa", "" ], [ "Pisarski", "Robert D.", "" ] ]
At nonzero temperature in QCD, about the deconfining phase transition there is a "semi" quark gluon plasma (semi-QGP), where the expectation value of the (renormalized) Polyakov loop is less than one. This can be modeled by a semiclassical expansion about a constant field for the vector potential, A_0, which is diagonal in color. We compute the shear viscosity in the semi-QGP by using the Boltzmann equation in the presence of this background field. To leading, logarithmic order in weak coupling, the dominant diagrams are given by the usual scattering processes of 2 -> 2 particles. For simplicity we also assume that both the number of colors and flavors are large. Near the critical temperature T_c, where the expectation value of the Polyakov loop is small, the overall density of colored fields decreases according to their color representation, with the density of quarks vanishes linearly with the loop, and that of gluons, quadratically. This decrease in the overall density dominates changes in the transport cross section. As a result, relative to that in the perturbative QGP, near T_c the shear viscosity in the semi-QGP is suppressed by two powers of the Polyakov loop. In a semiclassical expansion, the suppression of colored fields depends only upon which color representation they lie in, and not upon their mass. That light and heavy quarks are suppressed in a common manner may help to explain the behavior of charm quarks at RHIC.
2108.00459
Avanish Basdew-Sharma
Avanish Basdew-Sharma
Towards DIS at N4LO
Contribution to the proceedings (SciPost) of `DIS 2021', Virtual Event @ Stony Brook University, Stony Brook, NY, April 12-16, 2021
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We will report on an ongoing effort towards calculating the N4LO perturbative QCD corrections to the DIS total inclusive cross-section. We are developing a method based on differential equations and series expansion in the inverse Bjorken parameter. As a byproduct our calculation should also deliver analytic or at least precise numerical approximations for the four-loop splitting functions.
[ { "created": "Sun, 1 Aug 2021 13:52:10 GMT", "version": "v1" } ]
2021-08-03
[ [ "Basdew-Sharma", "Avanish", "" ] ]
We will report on an ongoing effort towards calculating the N4LO perturbative QCD corrections to the DIS total inclusive cross-section. We are developing a method based on differential equations and series expansion in the inverse Bjorken parameter. As a byproduct our calculation should also deliver analytic or at least precise numerical approximations for the four-loop splitting functions.
hep-ph/0702139
Manmohan Gupta
Harleen Dahiya, Manmohan Gupta and J.M.S. Rana
Implications of \eta' Coupling in the Chiral Constituent Quark Model
7 pages, 2 tables. Presented at the 17th International Spin Physics Symposium, Kyoto, Japan, October 2-7, 2006
AIPConf.Proc.915:474-477,2007
10.1063/1.2750823
null
hep-ph
null
Using the latest data pertaining to \bar u-\bar d asymmetry and the spin polarization functions, detailed implications of the possible values of the coupling strength of the singlet Goldstone boson \eta' have been investigated in the \chiCQM with configuration mixing. Using \Delta u, \Delta_3, \bar u-\bar d and \bar u/\bar d, the possible ranges of the coupling parameters a, \alpha^2 a, \beta^2 a and \zeta^2 a, representing respectively the probabilities of fluctuations to pions, K, \eta and \eta^{'}, are found. To further constrain the coupling strength of \eta', detailed fits have been obtained for spin polarization functions, quark distribution functions and baryon octet magnetic moments. The fits clearly establish that a small non-zero value of the coupling of \eta' is preferred over the higher values of $\eta'$ as well as when \zeta=0, the latter implying the absence of \eta' from the dynamics of \chiCQM. Our best fit achieves an overall excellent fit to the data, in particular for \Delta u, \Delta d, \Delta_8 as well as the magnetic moments \mu_{n}, \mu_{\Sigma^-}, \mu_{\Sigma^+} and \mu_{\Xi^-}. The implications of \eta' on the gluon polarization have also been investigated.
[ { "created": "Wed, 14 Feb 2007 05:19:47 GMT", "version": "v1" } ]
2008-11-26
[ [ "Dahiya", "Harleen", "" ], [ "Gupta", "Manmohan", "" ], [ "Rana", "J. M. S.", "" ] ]
Using the latest data pertaining to \bar u-\bar d asymmetry and the spin polarization functions, detailed implications of the possible values of the coupling strength of the singlet Goldstone boson \eta' have been investigated in the \chiCQM with configuration mixing. Using \Delta u, \Delta_3, \bar u-\bar d and \bar u/\bar d, the possible ranges of the coupling parameters a, \alpha^2 a, \beta^2 a and \zeta^2 a, representing respectively the probabilities of fluctuations to pions, K, \eta and \eta^{'}, are found. To further constrain the coupling strength of \eta', detailed fits have been obtained for spin polarization functions, quark distribution functions and baryon octet magnetic moments. The fits clearly establish that a small non-zero value of the coupling of \eta' is preferred over the higher values of $\eta'$ as well as when \zeta=0, the latter implying the absence of \eta' from the dynamics of \chiCQM. Our best fit achieves an overall excellent fit to the data, in particular for \Delta u, \Delta d, \Delta_8 as well as the magnetic moments \mu_{n}, \mu_{\Sigma^-}, \mu_{\Sigma^+} and \mu_{\Xi^-}. The implications of \eta' on the gluon polarization have also been investigated.
1901.03805
Ke-Sheng Sun
Ke-Sheng Sun, Xiu-Yi Yang
The LFV decays $B^0_{d,s}\rightarrow e\mu(e\tau,\mu\tau)$ with one neutral singlet scalar
20 pages,8 figures
Mod.Phys.Lett. A33 (2018) no.36, 1850214
10.1142/S0217732318502140
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Taking account of the constraint from radiative two body decays $l_i\rightarrow l_j\gamma$, we investigate the Lepton Flavor Violation decays $B^0_q\rightarrow\bar{l_l}l_k$ in the framework of the minimal extension of the Standard Model with one neutral singlet scalar. The couplings $C_{e\mu}$, $C_{e\tau}$ and $C_{\mu\tau}$ between the different generation leptons and scalar $S^0$ are constrained by the current bounds of $l_i\rightarrow l_j\gamma$. The numerical results show that the theoretical prediction of $B^0_q\rightarrow\bar{l_l}l_k$ strongly depend on the couplings $C_{qb}$ ($q=d\;or\; s$) between down type quarks and new scalar. The contributions from couplings $C_{uc}$, $C_{ut}$ and $C_{ct}$ between up type quark and new scalar are less dominant.
[ { "created": "Sat, 12 Jan 2019 05:55:04 GMT", "version": "v1" } ]
2019-01-15
[ [ "Sun", "Ke-Sheng", "" ], [ "Yang", "Xiu-Yi", "" ] ]
Taking account of the constraint from radiative two body decays $l_i\rightarrow l_j\gamma$, we investigate the Lepton Flavor Violation decays $B^0_q\rightarrow\bar{l_l}l_k$ in the framework of the minimal extension of the Standard Model with one neutral singlet scalar. The couplings $C_{e\mu}$, $C_{e\tau}$ and $C_{\mu\tau}$ between the different generation leptons and scalar $S^0$ are constrained by the current bounds of $l_i\rightarrow l_j\gamma$. The numerical results show that the theoretical prediction of $B^0_q\rightarrow\bar{l_l}l_k$ strongly depend on the couplings $C_{qb}$ ($q=d\;or\; s$) between down type quarks and new scalar. The contributions from couplings $C_{uc}$, $C_{ut}$ and $C_{ct}$ between up type quark and new scalar are less dominant.
1807.00621
Fernand M Renard
Fernand M Renard
W polarization in $e^+e^-$, gluon-gluon and $\gamma\gamma \to W t\bar b $ for testing the top quark mass structure and the presence of final interactions
17 pages, 12 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the $Wt\bar b$ production processes and especially the rate of longitudinal $W$ polarization sensitive to a possible top quark mass scale dependence and to the presence of strong final state $Wt$ interactions for example generated by a dark matter environment. We give illustrations for the three processes $e^+e^-$, gluon-gluon and $\gamma\gamma \to W t\bar b $.
[ { "created": "Mon, 2 Jul 2018 12:22:26 GMT", "version": "v1" } ]
2018-07-03
[ [ "Renard", "Fernand M", "" ] ]
We analyze the $Wt\bar b$ production processes and especially the rate of longitudinal $W$ polarization sensitive to a possible top quark mass scale dependence and to the presence of strong final state $Wt$ interactions for example generated by a dark matter environment. We give illustrations for the three processes $e^+e^-$, gluon-gluon and $\gamma\gamma \to W t\bar b $.
hep-ph/9902327
Michael Strickland
Jens O. Andersen, Eric Braaten, and Michael Strickland
Hard-thermal-loop Resummation of the Free Energy of a Hot Gluon Plasma
9 pages, 1 figure
Phys.Rev.Lett. 83 (1999) 2139-2142
10.1103/PhysRevLett.83.2139
null
hep-ph nucl-th
null
We calculate the free energy of a hot gluon plasma to leading order in hard-thermal-loop perturbation theory. Effects associated with screening, gluon quasiparticles, and Landau damping are resummed to all orders. The ultraviolet divergences generated by the hard-thermal-loop propagator corrections can be cancelled by a temperature-independent counterterm. The deviation of the hard-thermal-loop free energy from lattice QCD results for T > 2 T_c has the correct sign and roughly the correct magnitude to be accounted for by next-to-leading order corrections.
[ { "created": "Thu, 11 Feb 1999 20:24:16 GMT", "version": "v1" }, { "created": "Fri, 14 May 1999 15:04:42 GMT", "version": "v2" } ]
2009-10-31
[ [ "Andersen", "Jens O.", "" ], [ "Braaten", "Eric", "" ], [ "Strickland", "Michael", "" ] ]
We calculate the free energy of a hot gluon plasma to leading order in hard-thermal-loop perturbation theory. Effects associated with screening, gluon quasiparticles, and Landau damping are resummed to all orders. The ultraviolet divergences generated by the hard-thermal-loop propagator corrections can be cancelled by a temperature-independent counterterm. The deviation of the hard-thermal-loop free energy from lattice QCD results for T > 2 T_c has the correct sign and roughly the correct magnitude to be accounted for by next-to-leading order corrections.
1307.7625
Georg Raffelt
Georg Raffelt, David de Sousa Seixas
Neutrino flavor pendulum in both mass hierarchies
5 pages, 2 figures, very small corrections, matches PRD version
Phys. Rev. D 88, 045031 (2013)
10.1103/PhysRevD.88.045031
MPP-2013-214
hep-ph astro-ph.SR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We construct a simple example for self-induced flavor conversion in dense neutrino gases showing new solutions that violate the symmetries of initial conditions. Our system consists of two opposite momentum modes 1 and 2, each initially occupied with equal densities of nu_e and anti-nu_e. Restricting solutions to symmetry under 1 <-> 2 allows for the usual bimodal instability ("flavor pendulum") in the inverted neutrino mass hierarchy (IH) and stability (no self-induced flavor conversion) in the normal hierarchy (NH). Lifting this symmetry restriction allows for a second pendulum-like solution that occurs in NH where the modes 1 and 2 swing in opposite directions in flavor space. Any small deviation from 1-2 symmetry in the initial condition triggers the new instability in NH. This effect corresponds to the recently identified multi-azimuth angle (MAA) instability of supernova neutrino fluxes. Both cases show explicitly that solutions of the equations of collective flavor oscillations need not inherit the symmetries of initial conditions, although this has been universally assumed.
[ { "created": "Mon, 29 Jul 2013 15:52:03 GMT", "version": "v1" }, { "created": "Fri, 30 Aug 2013 14:46:10 GMT", "version": "v2" } ]
2013-09-02
[ [ "Raffelt", "Georg", "" ], [ "Seixas", "David de Sousa", "" ] ]
We construct a simple example for self-induced flavor conversion in dense neutrino gases showing new solutions that violate the symmetries of initial conditions. Our system consists of two opposite momentum modes 1 and 2, each initially occupied with equal densities of nu_e and anti-nu_e. Restricting solutions to symmetry under 1 <-> 2 allows for the usual bimodal instability ("flavor pendulum") in the inverted neutrino mass hierarchy (IH) and stability (no self-induced flavor conversion) in the normal hierarchy (NH). Lifting this symmetry restriction allows for a second pendulum-like solution that occurs in NH where the modes 1 and 2 swing in opposite directions in flavor space. Any small deviation from 1-2 symmetry in the initial condition triggers the new instability in NH. This effect corresponds to the recently identified multi-azimuth angle (MAA) instability of supernova neutrino fluxes. Both cases show explicitly that solutions of the equations of collective flavor oscillations need not inherit the symmetries of initial conditions, although this has been universally assumed.
2004.09825
Lara Mason
Alan S. Cornell, Aldo Deandrea, Benjamin Fuks, Lara Mason
Future lepton collider prospects for a ubiquitous composite pseudo-scalar
16 pages, 9 figures. To appear in Physical Review D (PRD)
Phys. Rev. D 102, 035030 (2020)
10.1103/PhysRevD.102.035030
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Composite Higgs models feature new strong dynamics leading to the description of the Higgs boson as a bound state arising from the breaking of a global (flavour) symmetry. These models generally include light states generated by the same dynamics, the detection of which may present the first observable signs of compositeness. One such state is a pseudo-scalar boson resulting from the breaking of a $U(1)$ symmetry common to most composite setups, and whose hints are expected to be visible through low-mass resonance searches at present and future hadron and lepton colliders. In this work we study the phenomenology of this pseudo-scalar field. We show that, for a light state, bottom quark loop effects dominantly impact the production cross section and considerably modify the decay pattern. Moreover, we make a case for targeted low-mass analyses at future lepton colliders, with an emphasis on high-luminosity machines aiming to operate at low centre-of-mass energies. We present a simplified outline of a search for this light pseudo-scalar at one such machine, considering electron-positron collisions at the $Z$-pole. We focus on a signature arising from the pseudo-scalar decay into a pair of hadronic taus and a production mode association with a pair of leptons of opposite electric charges, and compare cut and count methods with machine learning methods.
[ { "created": "Tue, 21 Apr 2020 08:42:33 GMT", "version": "v1" }, { "created": "Thu, 27 Aug 2020 10:01:19 GMT", "version": "v2" } ]
2020-09-09
[ [ "Cornell", "Alan S.", "" ], [ "Deandrea", "Aldo", "" ], [ "Fuks", "Benjamin", "" ], [ "Mason", "Lara", "" ] ]
Composite Higgs models feature new strong dynamics leading to the description of the Higgs boson as a bound state arising from the breaking of a global (flavour) symmetry. These models generally include light states generated by the same dynamics, the detection of which may present the first observable signs of compositeness. One such state is a pseudo-scalar boson resulting from the breaking of a $U(1)$ symmetry common to most composite setups, and whose hints are expected to be visible through low-mass resonance searches at present and future hadron and lepton colliders. In this work we study the phenomenology of this pseudo-scalar field. We show that, for a light state, bottom quark loop effects dominantly impact the production cross section and considerably modify the decay pattern. Moreover, we make a case for targeted low-mass analyses at future lepton colliders, with an emphasis on high-luminosity machines aiming to operate at low centre-of-mass energies. We present a simplified outline of a search for this light pseudo-scalar at one such machine, considering electron-positron collisions at the $Z$-pole. We focus on a signature arising from the pseudo-scalar decay into a pair of hadronic taus and a production mode association with a pair of leptons of opposite electric charges, and compare cut and count methods with machine learning methods.
hep-ph/0201198
Bodenm\"uller
H. Fritzsch (TH Division, CERN)
Fundamental Constants at High Energy
8 pages
Fortsch.Phys. 50 (2002) 518-524
10.1002/1521-3978(200205)50:5/7<518::AID-PROP518>3.0.CO;2-F
LMU 01/14
hep-ph
null
The progress of Particle Physics is closely linked to the progress in the understanding of the fundamental constants, like the finestructure constant, the mass of the electron or nucleon, or the electroweak mixing angle. The relation between the 18 fundamental constants of the Standard Model and the elementary units used in other fields like quantum optics or solid state physics is far from trivial and will be discussed. Relations between the various constants might exist, providing signals for the physics beyond the Standard Model. Recent observations in astrophysics indicate a slight time variation of the finestructure constant. If true, it has profound implications for many particle and nuclear physics phenomena. In particular the nuclear mass scale should change in time, a phenomenon which could be observed in the laboratory using advanced methods of quantum optics.
[ { "created": "Tue, 22 Jan 2002 08:52:29 GMT", "version": "v1" } ]
2015-06-25
[ [ "Fritzsch", "H.", "", "TH Division, CERN" ] ]
The progress of Particle Physics is closely linked to the progress in the understanding of the fundamental constants, like the finestructure constant, the mass of the electron or nucleon, or the electroweak mixing angle. The relation between the 18 fundamental constants of the Standard Model and the elementary units used in other fields like quantum optics or solid state physics is far from trivial and will be discussed. Relations between the various constants might exist, providing signals for the physics beyond the Standard Model. Recent observations in astrophysics indicate a slight time variation of the finestructure constant. If true, it has profound implications for many particle and nuclear physics phenomena. In particular the nuclear mass scale should change in time, a phenomenon which could be observed in the laboratory using advanced methods of quantum optics.
2110.14107
Gilberto Ramalho
G. Ramalho, K. Tsushima and J.P.B.C. de Melo
Electromagnetic form factors of baryons in nuclear medium
Proceedings of conference PANIC 2021. 5 pages, 3 figures
null
null
LFTC-21-4/65
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://creativecommons.org/licenses/by-nc-nd/4.0/
The electromagnetic structure of the baryons is modified in the nuclear medium. The modifications can be inferred from the comparison between the electromagnetic form factors in medium with the respective form factor in vacuum. Of particular interest is the ratio between the electric and magnetic form factors in medium ($G_E^*/G_M^*$) and vacuum ($G_E/G_M$) of the octet baryon. The deviation of the double ratios ($G_E^*/G_M^*)/(G_E/G_M)$ from unity measures the impact of the medium modification of the electromagnetic structure in a nuclear medium. Measurements of the double ratios $(G_E^*/G_M^*)/(G_E/G_M)$ for different nuclear densities may become available in a near future using the polarization-transfer method developed at Jefferson Lab. We present estimates of the double ratios of octet baryons based on a covariant constituent quark model, which takes into account pion cloud excitations of the baryon cores,for different nuclear densities. Our results manifest different features, namely, enhancement or quenching depending on the baryon flavor content.
[ { "created": "Wed, 27 Oct 2021 01:09:24 GMT", "version": "v1" } ]
2021-10-28
[ [ "Ramalho", "G.", "" ], [ "Tsushima", "K.", "" ], [ "de Melo", "J. P. B. C.", "" ] ]
The electromagnetic structure of the baryons is modified in the nuclear medium. The modifications can be inferred from the comparison between the electromagnetic form factors in medium with the respective form factor in vacuum. Of particular interest is the ratio between the electric and magnetic form factors in medium ($G_E^*/G_M^*$) and vacuum ($G_E/G_M$) of the octet baryon. The deviation of the double ratios ($G_E^*/G_M^*)/(G_E/G_M)$ from unity measures the impact of the medium modification of the electromagnetic structure in a nuclear medium. Measurements of the double ratios $(G_E^*/G_M^*)/(G_E/G_M)$ for different nuclear densities may become available in a near future using the polarization-transfer method developed at Jefferson Lab. We present estimates of the double ratios of octet baryons based on a covariant constituent quark model, which takes into account pion cloud excitations of the baryon cores,for different nuclear densities. Our results manifest different features, namely, enhancement or quenching depending on the baryon flavor content.
2102.03458
Leendert Hayen
Leendert Hayen
Radiative corrections to nucleon weak charges and Beyond Standard Model impact
null
null
null
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The nucleon axial charge is a central ingredient in nuclear and particle physics, and a key observable in precision tests of the electroweak Standard Model sector and beyond. We report on the first complete calculation of its electroweak quantum corrections up to $\mathcal{O}(\alpha)$, using a combination of current algebra techniques and QCD sum rules. We find a substantial enhancement due to the weak magnetism contribution in the elastic channel, and include higher-twist and target mass corrections at low $Q^2$ to find $\Delta_R^A = 0.02881(22)$. Using analogous methods, we determine a new value for the vector charge renormalization, $\Delta_R^V = 0.02474(27)$, and show how the two most recent calculations can be brought into agreement. This allows us to determine a corrected experimental $g_A^0 = 1.2730(13)$, which is a $>2\sigma$ shift away from the commonly quoted value. We use this new result to set constraints on exotic right-handed currents by comparing to lattice QCD results, and resolve a double-counting issue in the $|V_{ud}|$ extraction from mirror decays.
[ { "created": "Sat, 6 Feb 2021 00:24:06 GMT", "version": "v1" } ]
2021-02-09
[ [ "Hayen", "Leendert", "" ] ]
The nucleon axial charge is a central ingredient in nuclear and particle physics, and a key observable in precision tests of the electroweak Standard Model sector and beyond. We report on the first complete calculation of its electroweak quantum corrections up to $\mathcal{O}(\alpha)$, using a combination of current algebra techniques and QCD sum rules. We find a substantial enhancement due to the weak magnetism contribution in the elastic channel, and include higher-twist and target mass corrections at low $Q^2$ to find $\Delta_R^A = 0.02881(22)$. Using analogous methods, we determine a new value for the vector charge renormalization, $\Delta_R^V = 0.02474(27)$, and show how the two most recent calculations can be brought into agreement. This allows us to determine a corrected experimental $g_A^0 = 1.2730(13)$, which is a $>2\sigma$ shift away from the commonly quoted value. We use this new result to set constraints on exotic right-handed currents by comparing to lattice QCD results, and resolve a double-counting issue in the $|V_{ud}|$ extraction from mirror decays.
hep-ph/9609273
null
P. J. Bussey (University of Glasgow), B. B. Levchenko, A. Shumilin (Moscow State University)
Prompt photon, Drell-Yan and Bethe-Heitler processes in hard photoproduction
6 pages, 3 embedded figures. To appear in the proceedings of the workshop "Future physics at HERA"
null
null
GLAS-PPE/96-06, INP-MSU-96-26/433
hep-ph
null
We present prospects and requirements for the study at HERA of hard photon processes which generate high $p_T$ photons in the final state, and processes which generate Drell-Yan lepton pairs.
[ { "created": "Fri, 6 Sep 1996 20:47:49 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bussey", "P. J.", "", "University of Glasgow" ], [ "Levchenko", "B. B.", "", "Moscow State University" ], [ "Shumilin", "A.", "", "Moscow State University" ] ]
We present prospects and requirements for the study at HERA of hard photon processes which generate high $p_T$ photons in the final state, and processes which generate Drell-Yan lepton pairs.
0904.3600
Mathias Garny
Mathias Garny, Markus Michael Muller
Kadanoff-Baym Equations with Non-Gaussian Initial Conditions: The Equilibrium Limit
24 pages, 8 figures, matches published version
Phys.Rev.D80:085011,2009
10.1103/PhysRevD.80.085011
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The nonequilibrium dynamics of quantum fields is an initial-value problem, which can be described by Kadanoff-Baym equations. Typically, and in particular when numerical solutions are demanded, these Kadanoff-Baym equations are restricted to Gaussian initial states. However, physical initial states are non-Gaussian correlated initial states. In particular, renormalizability requires the initial state to feature n-point correlations that asymptotically agree with the vacuum correlations at short distances. In order to identify physical nonequilibrium initial states, it is therefore a precondition to describe the vacuum correlations of the interacting theory within the nonequilibrium framework. In this paper, Kadanoff-Baym equations for non-Gaussian correlated initial states describing vacuum and thermal equilibrium are derived from the 2PI effective action. A diagrammatic method for the explicit construction of vacuum and thermal initial correlations from the 2PI effective action is provided. We present numerical solutions of Kadanoff-Baym equations for a real scalar Phi^4 quantum field theory which take the thermal initial 4-point correlation as the leading non-Gaussian correction into account. We find that this minimal non-Gaussian initial condition yields an approximation to the complete equilibrium initial state that is quantitatively and qualitatively significantly improved as compared to Gaussian initial states.
[ { "created": "Thu, 23 Apr 2009 14:42:30 GMT", "version": "v1" }, { "created": "Tue, 1 Dec 2009 08:50:13 GMT", "version": "v2" } ]
2009-12-01
[ [ "Garny", "Mathias", "" ], [ "Muller", "Markus Michael", "" ] ]
The nonequilibrium dynamics of quantum fields is an initial-value problem, which can be described by Kadanoff-Baym equations. Typically, and in particular when numerical solutions are demanded, these Kadanoff-Baym equations are restricted to Gaussian initial states. However, physical initial states are non-Gaussian correlated initial states. In particular, renormalizability requires the initial state to feature n-point correlations that asymptotically agree with the vacuum correlations at short distances. In order to identify physical nonequilibrium initial states, it is therefore a precondition to describe the vacuum correlations of the interacting theory within the nonequilibrium framework. In this paper, Kadanoff-Baym equations for non-Gaussian correlated initial states describing vacuum and thermal equilibrium are derived from the 2PI effective action. A diagrammatic method for the explicit construction of vacuum and thermal initial correlations from the 2PI effective action is provided. We present numerical solutions of Kadanoff-Baym equations for a real scalar Phi^4 quantum field theory which take the thermal initial 4-point correlation as the leading non-Gaussian correction into account. We find that this minimal non-Gaussian initial condition yields an approximation to the complete equilibrium initial state that is quantitatively and qualitatively significantly improved as compared to Gaussian initial states.
hep-ph/0307396
Christopher D. Carone
Carl E. Carlson, Christopher D. Carone, Herry J. Kwee, and Vahagn Nazaryan (William and Mary)
Phenomenology of the Pentaquark Antidecuplet
12 pages LaTeX, 1 eps figure
Phys.Lett. B573 (2003) 101-108
10.1016/j.physletb.2003.08.050
WM-03-105
hep-ph nucl-th
null
We consider the mass splittings and strong decays of members of the lowest-lying pentaquark multiplet, which we take to be a parity-odd antidecuplet. We derive useful decompositions of the quark model wave functions that allow for easy computation of color-flavor-spin matrix elements. We compute mass splittings within the antidecuplet including spin-color and spin-isospin interactions between constituents and point out the importance of hidden strangeness in rendering the nucleon-like states heavier than the S=1 state. Using recent experimental data on a possible S=1 pentaquark state, we make decay predictions for other members of the antidecuplet.
[ { "created": "Thu, 31 Jul 2003 19:43:45 GMT", "version": "v1" }, { "created": "Wed, 6 Aug 2003 19:33:06 GMT", "version": "v2" } ]
2015-06-25
[ [ "Carlson", "Carl E.", "", "William and Mary" ], [ "Carone", "Christopher D.", "", "William and Mary" ], [ "Kwee", "Herry J.", "", "William and Mary" ], [ "Nazaryan", "Vahagn", "", "William and Mary" ] ]
We consider the mass splittings and strong decays of members of the lowest-lying pentaquark multiplet, which we take to be a parity-odd antidecuplet. We derive useful decompositions of the quark model wave functions that allow for easy computation of color-flavor-spin matrix elements. We compute mass splittings within the antidecuplet including spin-color and spin-isospin interactions between constituents and point out the importance of hidden strangeness in rendering the nucleon-like states heavier than the S=1 state. Using recent experimental data on a possible S=1 pentaquark state, we make decay predictions for other members of the antidecuplet.
hep-ph/9612434
Jose Wudka
Martin B Einhorn and Jose Wudka
On effective interactions containing $\partial . W^\pm$ and $\partial . Z$ factors
5 pages, no figures, REVTeX
Phys.Rev. D55 (1997) 3219-3220
10.1103/PhysRevD.55.3219
UCRHEP-T171 UM-HEP-96-12
hep-ph
null
The effects of effective interactions containing the factors $\partial \cdot W^\pm$ and $\partial \cdot Z$ is studied within a consistent effective Lagrangian formalism. It is shown that such terms are redundant
[ { "created": "Fri, 20 Dec 1996 18:40:04 GMT", "version": "v1" } ]
2009-10-30
[ [ "Einhorn", "Martin B", "" ], [ "Wudka", "Jose", "" ] ]
The effects of effective interactions containing the factors $\partial \cdot W^\pm$ and $\partial \cdot Z$ is studied within a consistent effective Lagrangian formalism. It is shown that such terms are redundant
hep-ph/0105100
Jonathan Feng
Jonathan L. Feng, Michael E. Peskin
Selectron Studies at e-e- and e+e- Colliders
16 pages, 11 figures
Phys.Rev. D64 (2001) 115002
10.1103/PhysRevD.64.115002
MIT-CTP-3136, SLAC-PUB-8829
hep-ph hep-ex
null
Selectrons may be studied in both e-e- and e+e- collisions at future linear colliders. Relative to e+e-, the e-e- mode benefits from negligible backgrounds and \beta threshold behavior for identical selectron pair production, but suffers from luminosity degradation and increased initial state radiation and beamstrahlung. We include all of these effects and compare the potential for selectron mass measurements in the two modes. The virtues of the e-e- collider far outweigh its disadvantages. In particular, the selectron mass may be measured to 100 MeV with a total integrated luminosity of 1 fb^-1, while more than 100 fb^-1 is required in e+e- collisions for similar precision.
[ { "created": "Fri, 11 May 2001 06:27:22 GMT", "version": "v1" } ]
2009-11-07
[ [ "Feng", "Jonathan L.", "" ], [ "Peskin", "Michael E.", "" ] ]
Selectrons may be studied in both e-e- and e+e- collisions at future linear colliders. Relative to e+e-, the e-e- mode benefits from negligible backgrounds and \beta threshold behavior for identical selectron pair production, but suffers from luminosity degradation and increased initial state radiation and beamstrahlung. We include all of these effects and compare the potential for selectron mass measurements in the two modes. The virtues of the e-e- collider far outweigh its disadvantages. In particular, the selectron mass may be measured to 100 MeV with a total integrated luminosity of 1 fb^-1, while more than 100 fb^-1 is required in e+e- collisions for similar precision.
1303.2129
Alexei Prokudin
Alessandro Bacchetta, Alexei Prokudin
Evolution of the helicity and transversity Transverse-Momentum-Dependent parton distributions
11 pages, 4 figures
null
10.1016/j.nuclphysb.2013.07.013
JLAB-THY-13-1693
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions (TMDs), we describe their dependence on the factorization scale and rapidity cutoff, which is essential for phenomenological applications.
[ { "created": "Fri, 8 Mar 2013 21:31:22 GMT", "version": "v1" } ]
2015-06-15
[ [ "Bacchetta", "Alessandro", "" ], [ "Prokudin", "Alexei", "" ] ]
We examine the QCD evolution of the helicity and transversity parton distribution functions when including also their dependence on transverse momentum. Using an appropriate definition of these polarized transverse momentum distributions (TMDs), we describe their dependence on the factorization scale and rapidity cutoff, which is essential for phenomenological applications.
2201.06393
Xiang Liu
Qin-Song Zhou, Jun-Zhang Wang, Xiang Liu and Takayuki Matsuki
Identifying the contribution of higher $\rho$ mesons around 2 GeV in the $e^+ e^- \to \omega\pi^0$ and $e^+ e^- \to \rho \eta^{\prime}$ processes
8 pages, 4 figures and 3 tables
Phys.Rev. D, 105, 074035 (2022)
10.1103/PhysRevD.105.074035
null
hep-ph hep-ex
http://creativecommons.org/publicdomain/zero/1.0/
The properties of the light vector meson states around 2.0 GeV have been poorly understood for a long time, which has become a barrier to the expansion to higher light vector meson spectrum. Recently, the BESIII collaboration released the measurements of the $e^+ e^- \to \omega\pi^0$ and $e^+ e^- \to \rho\eta^{\prime}$ reactions above 2.0 GeV, both of which are ideal processes to study the isovector $\rho$ meson family. In this work, through carrying out a combined analysis of the Born cross section data for the above two processes with the theoretical support on mass spectrum, and production and strong decay behaviors of the $\rho$ meson family around 2.0 GeV, we identify the enhancement structure near 2034 MeV observed in $e^+e^-\to\omega\pi^0$ to be the interference contribution from two resonances $\rho(1900)$ and $\rho(2150)$, and another enhancement structure at 2111 MeV reported in $e^+e^-\to\rho\eta^{\prime}$ to be the contributions from $\rho(2000)$ and $\rho(2150)$. This conclusion means that the $e^+e^-\to\omega\pi^0$ and $e^+e^-\to\rho \eta^{\prime}$ are the excellent golden channels to establish $\rho(1900)$ and $\rho(2000)$, especially for a $D$-wave state $\rho(2000)$, whose experimental search in the $e^+e^-$ collision should be quite challenging. The relevant cross section measurements with higher precision are expected in the future BESIII and Belle II experiments.
[ { "created": "Mon, 17 Jan 2022 13:15:22 GMT", "version": "v1" }, { "created": "Sat, 30 Apr 2022 03:19:08 GMT", "version": "v2" } ]
2022-05-03
[ [ "Zhou", "Qin-Song", "" ], [ "Wang", "Jun-Zhang", "" ], [ "Liu", "Xiang", "" ], [ "Matsuki", "Takayuki", "" ] ]
The properties of the light vector meson states around 2.0 GeV have been poorly understood for a long time, which has become a barrier to the expansion to higher light vector meson spectrum. Recently, the BESIII collaboration released the measurements of the $e^+ e^- \to \omega\pi^0$ and $e^+ e^- \to \rho\eta^{\prime}$ reactions above 2.0 GeV, both of which are ideal processes to study the isovector $\rho$ meson family. In this work, through carrying out a combined analysis of the Born cross section data for the above two processes with the theoretical support on mass spectrum, and production and strong decay behaviors of the $\rho$ meson family around 2.0 GeV, we identify the enhancement structure near 2034 MeV observed in $e^+e^-\to\omega\pi^0$ to be the interference contribution from two resonances $\rho(1900)$ and $\rho(2150)$, and another enhancement structure at 2111 MeV reported in $e^+e^-\to\rho\eta^{\prime}$ to be the contributions from $\rho(2000)$ and $\rho(2150)$. This conclusion means that the $e^+e^-\to\omega\pi^0$ and $e^+e^-\to\rho \eta^{\prime}$ are the excellent golden channels to establish $\rho(1900)$ and $\rho(2000)$, especially for a $D$-wave state $\rho(2000)$, whose experimental search in the $e^+e^-$ collision should be quite challenging. The relevant cross section measurements with higher precision are expected in the future BESIII and Belle II experiments.
2112.02519
Jinwei Wang
Lin-Qing Gao, Xiao-Jun Bi, Jin-Wei Wang, Qian-Fei Xiang, and Peng-Fei Yin
Exploring Fermionic Multiplet Dark Matter through Precision Measurements at the CEPC
15 pages, 5 figures
null
10.1088/1674-1137/ac7547
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
New physics could be explored through loop effects by the precision measurements at the Circular Electron Positron Collider due to its clean collision environment and high luminosity. In this work, we focus on two dark matter models that involve additional electroweak fermionic multiplets. We calculate their one-loop corrections to five processes, i.e. $e^+e^- \to \mu^+\mu^-, ~Zh, ~ZZ, ~W^+W^-$, and $Z\gamma$, and investigate the corresponding signatures at CEPC with the projected sensitivity. We find that the detectable parameter regions of these processes are complementary. The combined analysis shows that the mass of dark matter $m_{\chi^0_1}$ in these two models can be probed up to $ \sim 150~\mathrm{GeV}$ and $\sim 450$ GeV at a 95\% confidence level, respectively.
[ { "created": "Sun, 5 Dec 2021 09:04:58 GMT", "version": "v1" } ]
2022-09-14
[ [ "Gao", "Lin-Qing", "" ], [ "Bi", "Xiao-Jun", "" ], [ "Wang", "Jin-Wei", "" ], [ "Xiang", "Qian-Fei", "" ], [ "Yin", "Peng-Fei", "" ] ]
New physics could be explored through loop effects by the precision measurements at the Circular Electron Positron Collider due to its clean collision environment and high luminosity. In this work, we focus on two dark matter models that involve additional electroweak fermionic multiplets. We calculate their one-loop corrections to five processes, i.e. $e^+e^- \to \mu^+\mu^-, ~Zh, ~ZZ, ~W^+W^-$, and $Z\gamma$, and investigate the corresponding signatures at CEPC with the projected sensitivity. We find that the detectable parameter regions of these processes are complementary. The combined analysis shows that the mass of dark matter $m_{\chi^0_1}$ in these two models can be probed up to $ \sim 150~\mathrm{GeV}$ and $\sim 450$ GeV at a 95\% confidence level, respectively.
1210.0116
Kirtiman Ghosh
Lusaka Bhattacharya, Kirtiman Ghosh and Katri Huitu
Top anti-top pairs at the LHC heavy ion collision: a new interesting probe of quark gluon plasma
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate top anti-top quark pair production in lead-lead collisions at the Large Hadron Collider with nucleon-nucleon center of mass energy of 5.5 TeV. Due to the very high temperature and energy density created in heavy ion collision, a new state of QCD matter known as Quark-Gluon Plasma (QGP) is expected to be produced. Top decay products loose energy inside the QGP medium. Therefore, we also study the medium modifications of different kinematic distributions. We observe significant modification in the dijets and trijets invariant mass distributions.We also found that the peak position and shape of the distributions could be used to characterize the nature of jet energy loss in the QGP.
[ { "created": "Sat, 29 Sep 2012 15:24:43 GMT", "version": "v1" } ]
2012-10-02
[ [ "Bhattacharya", "Lusaka", "" ], [ "Ghosh", "Kirtiman", "" ], [ "Huitu", "Katri", "" ] ]
We investigate top anti-top quark pair production in lead-lead collisions at the Large Hadron Collider with nucleon-nucleon center of mass energy of 5.5 TeV. Due to the very high temperature and energy density created in heavy ion collision, a new state of QCD matter known as Quark-Gluon Plasma (QGP) is expected to be produced. Top decay products loose energy inside the QGP medium. Therefore, we also study the medium modifications of different kinematic distributions. We observe significant modification in the dijets and trijets invariant mass distributions.We also found that the peak position and shape of the distributions could be used to characterize the nature of jet energy loss in the QGP.
0812.1144
Florian Marhauser
Florian Marhauser, Jan M. Pawlowski
Confinement in Polyakov Gauge
12 pages, 8 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We approach the non-perturbative regime in finite temperature QCD within a formulation in Polyakov gauge. The construction is based on a complete gauge fixing. Correlation functions are then computed from Wilsonian renormalisation group flows. First results for the confinement-deconfinement phase transition for SU(2) are presented. Within a simple approximation we obtain a second order phase transition within the Ising universality class. The critical temperature is computed as T_c = 305 MeV.
[ { "created": "Fri, 5 Dec 2008 19:31:43 GMT", "version": "v1" } ]
2008-12-08
[ [ "Marhauser", "Florian", "" ], [ "Pawlowski", "Jan M.", "" ] ]
We approach the non-perturbative regime in finite temperature QCD within a formulation in Polyakov gauge. The construction is based on a complete gauge fixing. Correlation functions are then computed from Wilsonian renormalisation group flows. First results for the confinement-deconfinement phase transition for SU(2) are presented. Within a simple approximation we obtain a second order phase transition within the Ising universality class. The critical temperature is computed as T_c = 305 MeV.
hep-ph/0506094
Tommy Ohlsson
Tommy Ohlsson
Bimaximal fermion mixing from the quark and leptonic mixing matrices
5 pages, RevTeX4. Final version published in Phys. Lett. B
Phys.Lett. B622 (2005) 159-164
10.1016/j.physletb.2005.07.003
null
hep-ph
null
In this paper, we show how the mixing angles of the standard parameterization add when multiplying the quark and leptonic mixing matrices, i.e., we derive explicit sum rules for the quark and leptonic mixing angles. In this connection, we also discuss other recently proposed sum rules for the mixing angles assuming bimaximal fermion mixing. In addition, we find that the present experimental and phenomenological data of the mixing angles naturally fulfill our sum rules, and thus, give rise to bilarge or bimaximal fermion mixing.
[ { "created": "Thu, 9 Jun 2005 14:34:49 GMT", "version": "v1" }, { "created": "Wed, 17 Aug 2005 10:52:41 GMT", "version": "v2" } ]
2009-11-11
[ [ "Ohlsson", "Tommy", "" ] ]
In this paper, we show how the mixing angles of the standard parameterization add when multiplying the quark and leptonic mixing matrices, i.e., we derive explicit sum rules for the quark and leptonic mixing angles. In this connection, we also discuss other recently proposed sum rules for the mixing angles assuming bimaximal fermion mixing. In addition, we find that the present experimental and phenomenological data of the mixing angles naturally fulfill our sum rules, and thus, give rise to bilarge or bimaximal fermion mixing.
1111.3175
Melin Huang
Melin Huang, S. D. Reitzner, Wei-Chun Tsai, Huitzu Tu
Global Neutrino Data Analysis and the Quest to Pin Down $\sin\theta_{13}$ in Different Mixing Matrix Parametrizations
14 pages, 10 figures, 3 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Hints for sizable $\sin^2 \theta_{13}$ have been reported in earlier global neutrino oscillation data analyses as well as will be reported in this work, and quite recently by the Double Chooz experiment. However, as we enter the era of precision neutrino oscillation experiments, terms linear in $\sin\theta_{13}$ will no longer be negligible, and its sign would affect the extraction of other oscillation parameters. The sign of $\sin\theta_{13}$ also plays a crucial role in the determination of the CP-violating phase. In this work we show that by adopting an alternative parametrization for the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix, one already has a chance to infer the sign of each mixing angle in the conventional parametrization using existing global neutrino data. A weak preference for negative $\sin \theta_{13}$ is found. In particular, the solar data suggest that $\sin\theta_{13} > 0$ while all other data the opposite. This leads to the speculation on whether the Mikheyev-Smirnov-Wolfenstein (MSW) effect is responsible. In this work we found that in the new mixing matrix parametrization, the 68% CL constraints on the three mixing angles are comparable to those estimated in the conventional parametrization adopted in the literature. Owing to the strong correlations among the three mixing angles in the new parametrization, the advantages of doing the global neutrino oscillation analysis using data from past, current, and near future neutrino oscillation experiments shall become manifest.
[ { "created": "Mon, 14 Nov 2011 10:58:15 GMT", "version": "v1" } ]
2011-11-15
[ [ "Huang", "Melin", "" ], [ "Reitzner", "S. D.", "" ], [ "Tsai", "Wei-Chun", "" ], [ "Tu", "Huitzu", "" ] ]
Hints for sizable $\sin^2 \theta_{13}$ have been reported in earlier global neutrino oscillation data analyses as well as will be reported in this work, and quite recently by the Double Chooz experiment. However, as we enter the era of precision neutrino oscillation experiments, terms linear in $\sin\theta_{13}$ will no longer be negligible, and its sign would affect the extraction of other oscillation parameters. The sign of $\sin\theta_{13}$ also plays a crucial role in the determination of the CP-violating phase. In this work we show that by adopting an alternative parametrization for the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) mixing matrix, one already has a chance to infer the sign of each mixing angle in the conventional parametrization using existing global neutrino data. A weak preference for negative $\sin \theta_{13}$ is found. In particular, the solar data suggest that $\sin\theta_{13} > 0$ while all other data the opposite. This leads to the speculation on whether the Mikheyev-Smirnov-Wolfenstein (MSW) effect is responsible. In this work we found that in the new mixing matrix parametrization, the 68% CL constraints on the three mixing angles are comparable to those estimated in the conventional parametrization adopted in the literature. Owing to the strong correlations among the three mixing angles in the new parametrization, the advantages of doing the global neutrino oscillation analysis using data from past, current, and near future neutrino oscillation experiments shall become manifest.
2004.01621
Bradley James Kavanagh
Bradley J. Kavanagh, Timon Emken, Riccardo Catena
Measuring the local Dark Matter density in the laboratory
6 pages, 3 figures. Monte Carlo and likelihood codes available at https://github.com/temken/DaMaSCUS/tree/v1.1 and https://github.com/bradkav/EarthScatterLikelihood respectively. v2: Updated with new benchmarks and improved analysis of detector resolution (widening uncertainties on the local density). Matches version published in PRD
Phys. Rev. D 104, 083023 (2021)
10.1103/PhysRevD.104.083023
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Despite strong evidence for the existence of large amounts of dark matter (DM) in our Universe, there is no direct indication of its presence in our own solar system. All estimates of the local DM density rely on extrapolating results on much larger scales. We demonstrate for the first time the possibility of simultaneously measuring the local DM density and interaction cross-section with a direct detection experiment. It relies on the assumption that incoming DM particles frequently scatter on terrestrial nuclei prior to detection, inducing an additional time-dependence of the signal. We show that for sub-GeV DM, with a large spin-independent DM-proton cross section, future direct detection experiments should be able to reconstruct the local DM density with smaller than 50% uncertainty.
[ { "created": "Fri, 3 Apr 2020 15:24:57 GMT", "version": "v1" }, { "created": "Wed, 22 Dec 2021 14:03:34 GMT", "version": "v2" } ]
2021-12-23
[ [ "Kavanagh", "Bradley J.", "" ], [ "Emken", "Timon", "" ], [ "Catena", "Riccardo", "" ] ]
Despite strong evidence for the existence of large amounts of dark matter (DM) in our Universe, there is no direct indication of its presence in our own solar system. All estimates of the local DM density rely on extrapolating results on much larger scales. We demonstrate for the first time the possibility of simultaneously measuring the local DM density and interaction cross-section with a direct detection experiment. It relies on the assumption that incoming DM particles frequently scatter on terrestrial nuclei prior to detection, inducing an additional time-dependence of the signal. We show that for sub-GeV DM, with a large spin-independent DM-proton cross section, future direct detection experiments should be able to reconstruct the local DM density with smaller than 50% uncertainty.
1302.3825
James P. Kneller
James P. Kneller, Alex W. Mauney
The consequences of large \theta_13 for the turbulence signatures in supernova neutrinos
null
null
10.1103/PhysRevD.88.025004
null
hep-ph astro-ph.SR
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The set of transition probabilities for a single neutrino emitted from a point source after passage through a turbulent supernova density profile have been found to be random variates drawn from parent distributions whose properties depend upon the stage of the explosion, the neutrino energy and mixing parameters, the observed channel, and the properties of the turbulence such as the amplitude C*. In this paper we examine the consequences of the recently measured mixing angle \theta_13 upon the neutrino flavor transformation in supernova when passing through turbulence. We find the measurements of a relatively large value of \theta_13 means the neutrinos are relatively immune to small, C* < 1%, amplitude turbulence but as C* increases the turbulence effects grow rapidly and spread to all mixing channels. For C* > 10% the turbulence effects in the high (H) density resonance mixing channels are independent of \theta_13 but non-resonant mixing channels are more sensitive to turbulence when \theta_13 is large.
[ { "created": "Fri, 15 Feb 2013 18:05:15 GMT", "version": "v1" } ]
2015-06-15
[ [ "Kneller", "James P.", "" ], [ "Mauney", "Alex W.", "" ] ]
The set of transition probabilities for a single neutrino emitted from a point source after passage through a turbulent supernova density profile have been found to be random variates drawn from parent distributions whose properties depend upon the stage of the explosion, the neutrino energy and mixing parameters, the observed channel, and the properties of the turbulence such as the amplitude C*. In this paper we examine the consequences of the recently measured mixing angle \theta_13 upon the neutrino flavor transformation in supernova when passing through turbulence. We find the measurements of a relatively large value of \theta_13 means the neutrinos are relatively immune to small, C* < 1%, amplitude turbulence but as C* increases the turbulence effects grow rapidly and spread to all mixing channels. For C* > 10% the turbulence effects in the high (H) density resonance mixing channels are independent of \theta_13 but non-resonant mixing channels are more sensitive to turbulence when \theta_13 is large.
hep-ph/0507089
Boris Blok
B. Blok and L. Frankfurt
On the increase with relative distances of light cone operator product of currents and related phenomena
10 pages, several misprints eliminated, detailed explanation is added on the change of dipole size, wave function and coherence length near the unitarity limit
Phys.Lett.B630:49-57,2005
10.1016/j.physletb.2005.09.058
null
hep-ph
null
We show that in QCD in the leading twist approximation flavor singlet light cone current-current correlators increase with distances rapidly similar to the correlator of velocities in turbulence and argue that this property is precursor of phase transitions in high energy processes . It is shown that absence of spatial oscillations of current-current correlators follows from asymptotic freedom in QCD. We discuss also influence of this new long-range interaction on the wave function of dipole in high energy DIS processes near the black disc limit.
[ { "created": "Thu, 7 Jul 2005 14:14:36 GMT", "version": "v1" }, { "created": "Sun, 16 Oct 2005 13:14:41 GMT", "version": "v2" } ]
2014-11-18
[ [ "Blok", "B.", "" ], [ "Frankfurt", "L.", "" ] ]
We show that in QCD in the leading twist approximation flavor singlet light cone current-current correlators increase with distances rapidly similar to the correlator of velocities in turbulence and argue that this property is precursor of phase transitions in high energy processes . It is shown that absence of spatial oscillations of current-current correlators follows from asymptotic freedom in QCD. We discuss also influence of this new long-range interaction on the wave function of dipole in high energy DIS processes near the black disc limit.
1411.0741
Yang-Ting Chien
Yang-Ting Chien
Resummation of Jet Shapes and Extracting Properties of the Quark-Gluon Plasma
8 pages, 3 figures, to appear in the Proceedings of the QCD Evolution Workshop 2014, Santa Fe, NM, May 12-16, 2014
null
10.1142/S2010194515600472
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Understanding the properties of the quark-gluon plasma (QGP) that is produced in ultra-relativistic nucleus-nucleus collisions has been one of the top priorities of the heavy ion program at the LHC. Energetic jets are produced and subsequently quenched in the collisions. Such jet quenching phenomena provide promising tools to probe the medium properties by studying the modification of jets due to the medium interactions. Significant modifications of jet shapes have been measured. In this talk we focus on the calculation of jet shapes in both proton-proton and lead-lead collisions using soft-collinear effective theory (SCET), with Glauber gluon interactions in the medium. Large logarithms in jet shapes are resummed at next-to-leading logarithmic (NLL) accuracy by the renormalization-group evolution between hierarchical jet scales. The medium interactions contribute as power corrections, and we calculate the modification of jet shapes at leading order in opacity with the static QGP model. Preliminary results are presented with good agreement with the recent CMS jet shape measurements.
[ { "created": "Tue, 4 Nov 2014 00:12:50 GMT", "version": "v1" } ]
2015-06-23
[ [ "Chien", "Yang-Ting", "" ] ]
Understanding the properties of the quark-gluon plasma (QGP) that is produced in ultra-relativistic nucleus-nucleus collisions has been one of the top priorities of the heavy ion program at the LHC. Energetic jets are produced and subsequently quenched in the collisions. Such jet quenching phenomena provide promising tools to probe the medium properties by studying the modification of jets due to the medium interactions. Significant modifications of jet shapes have been measured. In this talk we focus on the calculation of jet shapes in both proton-proton and lead-lead collisions using soft-collinear effective theory (SCET), with Glauber gluon interactions in the medium. Large logarithms in jet shapes are resummed at next-to-leading logarithmic (NLL) accuracy by the renormalization-group evolution between hierarchical jet scales. The medium interactions contribute as power corrections, and we calculate the modification of jet shapes at leading order in opacity with the static QGP model. Preliminary results are presented with good agreement with the recent CMS jet shape measurements.
1510.09134
Luis Hernandez
Alejandro Ayala, C. A. Dominguez, L. A. Hernandez, M. Loewe, R. Zamora
Inverse magnetic catalysis from the properties of the QCD coupling in a magnetic field
Expanded discussion, references added. Version to appear in Phys. Lett. B
null
10.1016/j.physletb.2016.05.058
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the vacuum one-loop quark-gluon vertex correction at zero temperature in the presence of a magnetic field. From the vertex function we extract the effective quark-gluon coupling and show that it grows with increasing magnetic field strength. The effect is due to a subtle competition between the color charge associated to gluons and the color charge associated to quarks, the former being larger than the latter. In contrast, at high temperature the effective thermo-magnetic coupling results exclusively from the contribution of the color charge associated to quarks. This produces a decrease of the coupling with increasing field strength. We interpret the results in terms of a geometrical effect whereby the magnetic field induces, on average, a closer distance between the (electrically charged) quarks and antiquarks. At high temperature, since the effective coupling is proportional only to the color charge associated to quarks, such proximity with increasing field strength makes the effective coupling decrease due to asymptotic freedom. In turn, this leads to a decreasing quark condensate. In contrast, at zero temperature both the effective strong coupling and the quark condensate increase with increasing magnetic field. This is due to the color charge associated to gluons dominating over that associated to quarks, with both having the opposite sign. Thus, the gluons induce a kind of screening of the quark color charge, in spite of the quark-antiquark proximity. The implications of these results for the inverse magnetic catalysis phenomenon are discussed.
[ { "created": "Fri, 30 Oct 2015 15:45:12 GMT", "version": "v1" }, { "created": "Mon, 23 May 2016 10:16:19 GMT", "version": "v2" } ]
2016-06-01
[ [ "Ayala", "Alejandro", "" ], [ "Dominguez", "C. A.", "" ], [ "Hernandez", "L. A.", "" ], [ "Loewe", "M.", "" ], [ "Zamora", "R.", "" ] ]
We compute the vacuum one-loop quark-gluon vertex correction at zero temperature in the presence of a magnetic field. From the vertex function we extract the effective quark-gluon coupling and show that it grows with increasing magnetic field strength. The effect is due to a subtle competition between the color charge associated to gluons and the color charge associated to quarks, the former being larger than the latter. In contrast, at high temperature the effective thermo-magnetic coupling results exclusively from the contribution of the color charge associated to quarks. This produces a decrease of the coupling with increasing field strength. We interpret the results in terms of a geometrical effect whereby the magnetic field induces, on average, a closer distance between the (electrically charged) quarks and antiquarks. At high temperature, since the effective coupling is proportional only to the color charge associated to quarks, such proximity with increasing field strength makes the effective coupling decrease due to asymptotic freedom. In turn, this leads to a decreasing quark condensate. In contrast, at zero temperature both the effective strong coupling and the quark condensate increase with increasing magnetic field. This is due to the color charge associated to gluons dominating over that associated to quarks, with both having the opposite sign. Thus, the gluons induce a kind of screening of the quark color charge, in spite of the quark-antiquark proximity. The implications of these results for the inverse magnetic catalysis phenomenon are discussed.
2104.00140
Tom Tong
Wouter Dekens, Jordy de Vries, Tom Tong
Sterile neutrinos with non-standard interactions in $\beta$- and $0\nu\beta\beta$-decay experiments
27 pages, 5 figures
null
10.1007/JHEP08(2021)128
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Charged currents are probed in low-energy precision $\beta$-decay experiments and at high-energy colliders, both of which aim to measure or constrain signals of beyond-the-Standard-Model physics. In light of future $\beta$-decay and LHC measurements that will further explore these non-standard interactions, we investigate what neutrinoless double-$\beta$ decay ($0\nu\beta\beta$) experiments can tell us if a nonzero signal were to be found. Using a recently developed effective-field-theory framework, we consider the effects that interactions with right-handed neutrinos have on $0\nu\beta\beta$ and discuss the range of neutrino masses that current and future $0\nu\beta\beta$ measurements can probe, assuming neutrinos are Majorana particles. For non-standard interactions at the level suggested by recently observed hints in $\beta$ decays, we show that next-generation $0\nu\beta\beta$ experiments can determine the Dirac or Majorana nature of neutrinos, for sterile neutrino masses larger than $\mathcal O(10)$ eV.
[ { "created": "Wed, 31 Mar 2021 22:21:04 GMT", "version": "v1" }, { "created": "Mon, 3 May 2021 12:36:33 GMT", "version": "v2" }, { "created": "Sat, 4 Dec 2021 23:25:31 GMT", "version": "v3" } ]
2021-12-07
[ [ "Dekens", "Wouter", "" ], [ "de Vries", "Jordy", "" ], [ "Tong", "Tom", "" ] ]
Charged currents are probed in low-energy precision $\beta$-decay experiments and at high-energy colliders, both of which aim to measure or constrain signals of beyond-the-Standard-Model physics. In light of future $\beta$-decay and LHC measurements that will further explore these non-standard interactions, we investigate what neutrinoless double-$\beta$ decay ($0\nu\beta\beta$) experiments can tell us if a nonzero signal were to be found. Using a recently developed effective-field-theory framework, we consider the effects that interactions with right-handed neutrinos have on $0\nu\beta\beta$ and discuss the range of neutrino masses that current and future $0\nu\beta\beta$ measurements can probe, assuming neutrinos are Majorana particles. For non-standard interactions at the level suggested by recently observed hints in $\beta$ decays, we show that next-generation $0\nu\beta\beta$ experiments can determine the Dirac or Majorana nature of neutrinos, for sterile neutrino masses larger than $\mathcal O(10)$ eV.
hep-ph/0507205
Pedro Bicudo
Felipe J. Llanes-Estrada, Pedro Bicudo, Stephen R. Cotanch
Oddballs and a Low Odderon Intercept
4 pages, 2 figures, 1 table
Phys.Rev.Lett. 96 (2006) 081601
10.1103/PhysRevLett.96.081601
SLAC-PUB-11312
hep-ph
null
We report an odderon Regge trajectory emerging from a field theoretical Coulomb gauge QCD model for the odd signature JPC (P=C= -1) glueball states (oddballs). The trajectory intercept is clearly smaller than the pomeron and even the omega trajectory's intercept which provides an explanation for the nonobservation of the odderon in high energy scattering data. To further support this result we compare to glueball lattice data and also perform calculations with an alternative model based upon an exact Hamiltonian diagonalization for three constituent gluons.
[ { "created": "Sun, 17 Jul 2005 19:44:57 GMT", "version": "v1" } ]
2009-11-11
[ [ "Llanes-Estrada", "Felipe J.", "" ], [ "Bicudo", "Pedro", "" ], [ "Cotanch", "Stephen R.", "" ] ]
We report an odderon Regge trajectory emerging from a field theoretical Coulomb gauge QCD model for the odd signature JPC (P=C= -1) glueball states (oddballs). The trajectory intercept is clearly smaller than the pomeron and even the omega trajectory's intercept which provides an explanation for the nonobservation of the odderon in high energy scattering data. To further support this result we compare to glueball lattice data and also perform calculations with an alternative model based upon an exact Hamiltonian diagonalization for three constituent gluons.
hep-ph/9705294
Ingolf Kuss
M. Kuroda (Meiji Gakuin University), I. Kuss and D. Schildknecht (Bielefeld University)
A Simple Approximation of the One-Loop Corrected Cross Section for $e^+e^-\to W^+W^-$ at LEP 2
12 pages, LaTeX including 1 postscript figure, submitted to Phys. Lett. B
Phys.Lett. B409 (1997) 405-411
10.1016/S0370-2693(97)00868-X
BI-TP 97/15
hep-ph
null
Using the SU(2) gauge coupling, $g_{W^\pm} (M^2_{W^\pm})$, at the high-energy scale of $M_{W^\pm}$, defined by the (theoretical value of the) leptonic W-width, rather than using the low-energy value, defined via the Fermi coupling, $G_\mu$, in the Born approximation, and supplementing with Coulomb corrections and initial state radiation, errors with respect to the exact one-loop results for the differential cross section of $e^+e^-\to W^+W^-$ are below 1% at LEP 2 energies at all $W^+W^-$ production angles. A similar procedure is suggested to incorporate leading bosonic loop effects into four-fermion production in the fermion-loop scheme. The resulting accuracy below 1% is sufficient for LEP 2 experiments.
[ { "created": "Mon, 12 May 1997 12:53:08 GMT", "version": "v1" } ]
2016-09-06
[ [ "Kuroda", "M.", "", "Meiji Gakuin University" ], [ "Kuss", "I.", "", "Bielefeld University" ], [ "Schildknecht", "D.", "", "Bielefeld University" ] ]
Using the SU(2) gauge coupling, $g_{W^\pm} (M^2_{W^\pm})$, at the high-energy scale of $M_{W^\pm}$, defined by the (theoretical value of the) leptonic W-width, rather than using the low-energy value, defined via the Fermi coupling, $G_\mu$, in the Born approximation, and supplementing with Coulomb corrections and initial state radiation, errors with respect to the exact one-loop results for the differential cross section of $e^+e^-\to W^+W^-$ are below 1% at LEP 2 energies at all $W^+W^-$ production angles. A similar procedure is suggested to incorporate leading bosonic loop effects into four-fermion production in the fermion-loop scheme. The resulting accuracy below 1% is sufficient for LEP 2 experiments.
hep-ph/0508195
Mikko Laine
M. Laine
Real-time Chern-Simons term for hypermagnetic fields
13 pages
JHEP 0510:056,2005
10.1088/1126-6708/2005/10/056
null
hep-ph
null
If non-vanishing chemical potentials are assigned to chiral fermions, then a Chern-Simons term is induced for the corresponding gauge fields. In thermal equilibrium anomalous processes adjust the chemical potentials such that the coefficient of the Chern-Simons term vanishes, but it has been argued that there are non-equilibrium epochs in cosmology where this is not the case and that, consequently, certain fermionic number densities and large-scale (hypermagnetic) field strengths get coupled to each other. We generalise the Chern-Simons term to a real-time situation relevant for dynamical considerations, by deriving the anomalous Hard Thermal Loop effective action for the hypermagnetic fields, write down the corresponding equations of motion, and discuss some exponentially growing solutions thereof.
[ { "created": "Thu, 18 Aug 2005 16:20:17 GMT", "version": "v1" } ]
2010-02-03
[ [ "Laine", "M.", "" ] ]
If non-vanishing chemical potentials are assigned to chiral fermions, then a Chern-Simons term is induced for the corresponding gauge fields. In thermal equilibrium anomalous processes adjust the chemical potentials such that the coefficient of the Chern-Simons term vanishes, but it has been argued that there are non-equilibrium epochs in cosmology where this is not the case and that, consequently, certain fermionic number densities and large-scale (hypermagnetic) field strengths get coupled to each other. We generalise the Chern-Simons term to a real-time situation relevant for dynamical considerations, by deriving the anomalous Hard Thermal Loop effective action for the hypermagnetic fields, write down the corresponding equations of motion, and discuss some exponentially growing solutions thereof.
2105.08296
Hoang Bao Tran Tan
H. B. Tran Tan, A. Derevianko, V. A. Dzuba, and V. V. Flambaum
Atomic ionization by scalar dark matter and solar scalars
7 pages, 5 figures. 2nd version: appendix added, citations added, data files included. 3rd version: new results for CaOW_4 added
Phys. Rev. Lett. 127, 081301 (2021)
10.1103/PhysRevLett.127.081301
null
hep-ph physics.atom-ph
http://creativecommons.org/licenses/by/4.0/
We calculate the cross-sections of atomic ionization by absorption of scalar particles in the energy range from a few eV to 100 keV. We consider both nonrelativistic particles (dark matter candidates) and relativistic particles which may be produced inside Sun. We provide numerical results for atoms relevant for direct dark matter searches (O, Na, Ar, Ca, Ge, I, Xe, W and Tl). We identify a crucial flaw in previous calculations and show that they overestimated the ionization cross sections by several orders of magnitude due to violation of the orthogonality of the bound and continuum electron wave functions. Using our computed cross-sections, we interpret the recent data from the Xenon1T experiment, establishing the first direct bounds on coupling of scalars to electrons. We argue that the Xenon1T excess can be explained by the emission of scalars from the Sun. While our finding is in a similar tension with astrophysical bounds as the solar axion hypothesis, we establish direct limits on scalar DM for the $\sim 1-10\,\mathrm{keV}$ mass range. We also update axio-ionization cross-sections. Numerical data files are provided.
[ { "created": "Tue, 18 May 2021 06:03:55 GMT", "version": "v1" }, { "created": "Fri, 21 May 2021 16:26:54 GMT", "version": "v2" }, { "created": "Sun, 8 Aug 2021 22:52:21 GMT", "version": "v3" } ]
2021-08-25
[ [ "Tan", "H. B. Tran", "" ], [ "Derevianko", "A.", "" ], [ "Dzuba", "V. A.", "" ], [ "Flambaum", "V. V.", "" ] ]
We calculate the cross-sections of atomic ionization by absorption of scalar particles in the energy range from a few eV to 100 keV. We consider both nonrelativistic particles (dark matter candidates) and relativistic particles which may be produced inside Sun. We provide numerical results for atoms relevant for direct dark matter searches (O, Na, Ar, Ca, Ge, I, Xe, W and Tl). We identify a crucial flaw in previous calculations and show that they overestimated the ionization cross sections by several orders of magnitude due to violation of the orthogonality of the bound and continuum electron wave functions. Using our computed cross-sections, we interpret the recent data from the Xenon1T experiment, establishing the first direct bounds on coupling of scalars to electrons. We argue that the Xenon1T excess can be explained by the emission of scalars from the Sun. While our finding is in a similar tension with astrophysical bounds as the solar axion hypothesis, we establish direct limits on scalar DM for the $\sim 1-10\,\mathrm{keV}$ mass range. We also update axio-ionization cross-sections. Numerical data files are provided.
hep-ph/0110127
Steven B. Giddings
Steven B. Giddings
Black hole production in TeV-scale gravity, and the future of high energy physics
To appear in the proceedings of "Snowmass 2001;" 9 pages, revtex4. v2: minor corrections/changes to wording v3: changes to cosmic ray neutrino event rates
eConf C010630 (2001) P328
null
null
hep-ph gr-qc hep-th
null
If the Planck scale is near a TeV, black hole production should be possible at colliders, as well as by cosmic rays. I begin with a review of the two approaches to TeV-scale gravity, large extra dimensions and warped compactification, presented in a unified framework. Then properties of such black holes and estimates of their production rates are given, and consequences for the future of high-energy experimental physics are discussed.
[ { "created": "Wed, 10 Oct 2001 15:12:05 GMT", "version": "v1" }, { "created": "Sat, 13 Oct 2001 19:18:29 GMT", "version": "v2" }, { "created": "Thu, 1 Nov 2001 19:55:37 GMT", "version": "v3" } ]
2009-09-25
[ [ "Giddings", "Steven B.", "" ] ]
If the Planck scale is near a TeV, black hole production should be possible at colliders, as well as by cosmic rays. I begin with a review of the two approaches to TeV-scale gravity, large extra dimensions and warped compactification, presented in a unified framework. Then properties of such black holes and estimates of their production rates are given, and consequences for the future of high-energy experimental physics are discussed.
hep-ph/9809498
Steven Abel
Steven Abel and Carlos Savoy
Charge and Colour Breaking Constraints in the MSSM With Non-Universal SUSY Breaking
12 Pages plain latex; includes 1 postscript figure. Final version to appear in PLB
Phys.Lett.B444:119-126,1998
10.1016/S0370-2693(98)01362-8
CERN-TH 98/315
hep-ph
null
We examine charge/colour breaking along directions in supersymmetric field space which are F and D-flat. We catalogue the dangerous directions and include some new ones which have not previously been considered. Analytic expressions for the resulting constraints are provided which are valid for all patterns of supersymmetry breaking. As an example we consider a recently proposed pattern of supersymmetry breaking derived in Horava-Witten M-theory, and show that there is no choice of parameters for which the physical vacuum is a global minimum.
[ { "created": "Wed, 23 Sep 1998 13:08:53 GMT", "version": "v1" }, { "created": "Fri, 16 Oct 1998 10:19:27 GMT", "version": "v2" } ]
2008-11-26
[ [ "Abel", "Steven", "" ], [ "Savoy", "Carlos", "" ] ]
We examine charge/colour breaking along directions in supersymmetric field space which are F and D-flat. We catalogue the dangerous directions and include some new ones which have not previously been considered. Analytic expressions for the resulting constraints are provided which are valid for all patterns of supersymmetry breaking. As an example we consider a recently proposed pattern of supersymmetry breaking derived in Horava-Witten M-theory, and show that there is no choice of parameters for which the physical vacuum is a global minimum.
2105.08744
Arman Esmaili
Arman Esmaili
Violation of Equivalence Principle in Neutrino Sector: Probing the Extended Parameter Space
19 pages, 8 figures; v2: minor clarifications added, matches the version published in JCAP
JCAP07(2021)018
10.1088/1475-7516/2021/07/018
null
hep-ph astro-ph.HE
http://creativecommons.org/licenses/by-nc-nd/4.0/
The oscillation of neutrino flavors, due to its interferometry nature, is extremely sensitive to the phase differences developing during the propagation of neutrinos. In this paper we investigate the effect of the Violation of Equivalence Principle (VEP) on the flavor oscillation probabilities of atmospheric and cosmic neutrinos observed at neutrino telescopes such as IceCube. Assuming a general parameterization of VEP, dubbed extended parameter space, we show that the synergy between the collected data of high energy atmospheric and cosmic neutrinos severely constrains the VEP parameters. Also, the projected sensitivity of IceCube-Gen2 to VEP parameters is discussed.
[ { "created": "Tue, 18 May 2021 18:01:05 GMT", "version": "v1" }, { "created": "Wed, 14 Jul 2021 04:10:15 GMT", "version": "v2" } ]
2021-07-15
[ [ "Esmaili", "Arman", "" ] ]
The oscillation of neutrino flavors, due to its interferometry nature, is extremely sensitive to the phase differences developing during the propagation of neutrinos. In this paper we investigate the effect of the Violation of Equivalence Principle (VEP) on the flavor oscillation probabilities of atmospheric and cosmic neutrinos observed at neutrino telescopes such as IceCube. Assuming a general parameterization of VEP, dubbed extended parameter space, we show that the synergy between the collected data of high energy atmospheric and cosmic neutrinos severely constrains the VEP parameters. Also, the projected sensitivity of IceCube-Gen2 to VEP parameters is discussed.
hep-ph/0604001
Yue Chongxing
Chong-Xing Yue, Li Zhou, Shuo Yang
Little Higgs models and single top production at the LHC
17pages, 5 figures, discussions and references added, typos corrected
Eur.Phys.J.C48:243-249,2006
10.1140/epjc/s2006-02624-5
null
hep-ph
null
We investigate the corrections of the littlest Higgs(LH) model and the SU(3) simple group model to single top production at the CERN Large Hardon Collider(LHC). We find that the new gauge bosons $W_{H}^{\pm}$ predicted by the LH model can generate significant contributions to single top production via the s-channel process. The correction terms for the tree-level $Wqq'$ couplings coming from the SU(3) simple group model can give large contributions to the cross sections of the t-channel single top production process. We expect that the effects of the LH model and the SU(3) simple group model on single top production can be detected at the LHC experiments.
[ { "created": "Sat, 1 Apr 2006 08:49:45 GMT", "version": "v1" }, { "created": "Thu, 22 Jun 2006 11:58:03 GMT", "version": "v2" } ]
2009-01-07
[ [ "Yue", "Chong-Xing", "" ], [ "Zhou", "Li", "" ], [ "Yang", "Shuo", "" ] ]
We investigate the corrections of the littlest Higgs(LH) model and the SU(3) simple group model to single top production at the CERN Large Hardon Collider(LHC). We find that the new gauge bosons $W_{H}^{\pm}$ predicted by the LH model can generate significant contributions to single top production via the s-channel process. The correction terms for the tree-level $Wqq'$ couplings coming from the SU(3) simple group model can give large contributions to the cross sections of the t-channel single top production process. We expect that the effects of the LH model and the SU(3) simple group model on single top production can be detected at the LHC experiments.
1809.01143
Seodong Shin
Yeong Gyun Kim, Chan Beom Park, Seodong Shin
Collider probes of singlet fermionic dark matter scenarios for the Fermi gamma-ray excess
14 pages, 1 figure, 1 table
null
10.1007/JHEP12(2018)036
CTPU-PTC-18-28, EFI-18-13
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the collider signatures of the three benchmark points in the singlet fermionic dark matter model. The benchmark points, which were introduced previously to explain the Fermi gamma-ray excess by dark matter (DM) pair annihilation at the Galactic center, have definite predictions for future collider experiments such as the International Linear Collider and the High-Luminosity LHC. We consider four collider observables: (1) Higgs signal strength (essentially $hZZ$ coupling), (2) triple Higgs coupling, (3) exotic Higgs decay, and (4) direct production of a new scalar particle. The benchmark points are classified by the final states of the DM annihilation process: a pair of $b$ quarks, SM-like Higgs bosons, and new scalar particles. Each benchmark scenario has detectable new physics signals for the above collider observables that can be well tested in the future lepton and hadron colliders.
[ { "created": "Tue, 4 Sep 2018 18:00:00 GMT", "version": "v1" } ]
2018-12-26
[ [ "Kim", "Yeong Gyun", "" ], [ "Park", "Chan Beom", "" ], [ "Shin", "Seodong", "" ] ]
We investigate the collider signatures of the three benchmark points in the singlet fermionic dark matter model. The benchmark points, which were introduced previously to explain the Fermi gamma-ray excess by dark matter (DM) pair annihilation at the Galactic center, have definite predictions for future collider experiments such as the International Linear Collider and the High-Luminosity LHC. We consider four collider observables: (1) Higgs signal strength (essentially $hZZ$ coupling), (2) triple Higgs coupling, (3) exotic Higgs decay, and (4) direct production of a new scalar particle. The benchmark points are classified by the final states of the DM annihilation process: a pair of $b$ quarks, SM-like Higgs bosons, and new scalar particles. Each benchmark scenario has detectable new physics signals for the above collider observables that can be well tested in the future lepton and hadron colliders.
hep-ph/9911499
Luis E. Ibanez
L.E. Ibanez
The second string (phenomenology) revolution
15 pages, Latex file, no figures. Contribution to the proceedings of Strings 99, Potsdam (Germany), July 1999
Class.Quant.Grav.17:1117-1128,2000
10.1088/0264-9381/17/5/321
FTUAM-99/37; IFT-UAM/CSIC-99-44
hep-ph hep-th
null
In the past three years our views on how the standard model of particle physics could be embedded into string theory have dramatically changed. The heterotic string is no longer the only possibility for such an embedding and other perturbative (or non-perturbative) corners of M-theory, like Type I or Type II strings seem now possible. It has also been realized that the string scale $M_s$ is not necessary close to the Planck scale and could be much smaller, of order the intermediate scale $\sqrt{M_WM_p}$ or even close to the weak scale. In addition, semi-realistic three generation models have recently been constructed starting with Type IIB compact orientifolds. I briefly discuss some of these developements which represent a revolution in our understanding of string phenomenology.
[ { "created": "Fri, 26 Nov 1999 09:06:20 GMT", "version": "v1" } ]
2011-04-15
[ [ "Ibanez", "L. E.", "" ] ]
In the past three years our views on how the standard model of particle physics could be embedded into string theory have dramatically changed. The heterotic string is no longer the only possibility for such an embedding and other perturbative (or non-perturbative) corners of M-theory, like Type I or Type II strings seem now possible. It has also been realized that the string scale $M_s$ is not necessary close to the Planck scale and could be much smaller, of order the intermediate scale $\sqrt{M_WM_p}$ or even close to the weak scale. In addition, semi-realistic three generation models have recently been constructed starting with Type IIB compact orientifolds. I briefly discuss some of these developements which represent a revolution in our understanding of string phenomenology.
1303.0082
Tie-Jun Gao
Tie-Jun Gao, Tai-Fu Feng, Jian-Bin Chen
t-c gamma and t-cg in warped extra dimensions
arXiv admin note: text overlap with arXiv:0903.2415 by other authors
null
10.1007/JHEP02(2013)029
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we calculate the top quark rare decays t-cgamma and t-cg in the framework where the standard model is embedded in a warped extra dimension with the custodial symmetry SU(3)c*SU(2)L*SU(2)R*U(1)x*PLR. Adopting reasonable assumptions on the parameter space,we numerically find the branching ratios of t-cgamma exceeding 10^-6 and that of t-cg exceeding 10^-5 respectively, which can be detected in near future.
[ { "created": "Fri, 1 Mar 2013 04:29:25 GMT", "version": "v1" } ]
2013-03-04
[ [ "Gao", "Tie-Jun", "" ], [ "Feng", "Tai-Fu", "" ], [ "Chen", "Jian-Bin", "" ] ]
In this work, we calculate the top quark rare decays t-cgamma and t-cg in the framework where the standard model is embedded in a warped extra dimension with the custodial symmetry SU(3)c*SU(2)L*SU(2)R*U(1)x*PLR. Adopting reasonable assumptions on the parameter space,we numerically find the branching ratios of t-cgamma exceeding 10^-6 and that of t-cg exceeding 10^-5 respectively, which can be detected in near future.
1112.1261
Matti Jarvinen
Matti Jarvinen and Elias Kiritsis
Holographic Models for QCD in the Veneziano Limit
55+32 pages, 16 figures. v2: several comments, references, and a new figure added
null
10.1007/JHEP03(2012)002
CCTP-2011-30
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We construct a class of bottom-up holographic models with physics comparable to the one expected from QCD in the Veneziano limit of large N_f and N_c with fixed x = N_f/N_c. The models capture the holographic dynamics of the dilaton (dual to the YM coupling) and a tachyon (dual to the chiral condensate), and are parametrized by the real parameter x, which can take values within the range 0 <= x < 11/2. We analyze the saddle point solutions, and draw the phase diagram at zero temperature and density. The backreaction of flavor on the glue is fully included. We find the conformal window for x >= x_c, and the QCD-like phase with chiral symmetry breaking at x < x_c, where the critical value x_c lies close to four. We also find Miransky scaling as x -> x_c as well as Efimov-like saddle points. By calculating the holographic beta-functions, we demonstrate the "walking" behavior of the coupling in the region near and below x_c.
[ { "created": "Tue, 6 Dec 2011 13:00:27 GMT", "version": "v1" }, { "created": "Fri, 23 Dec 2011 15:31:16 GMT", "version": "v2" } ]
2015-06-03
[ [ "Jarvinen", "Matti", "" ], [ "Kiritsis", "Elias", "" ] ]
We construct a class of bottom-up holographic models with physics comparable to the one expected from QCD in the Veneziano limit of large N_f and N_c with fixed x = N_f/N_c. The models capture the holographic dynamics of the dilaton (dual to the YM coupling) and a tachyon (dual to the chiral condensate), and are parametrized by the real parameter x, which can take values within the range 0 <= x < 11/2. We analyze the saddle point solutions, and draw the phase diagram at zero temperature and density. The backreaction of flavor on the glue is fully included. We find the conformal window for x >= x_c, and the QCD-like phase with chiral symmetry breaking at x < x_c, where the critical value x_c lies close to four. We also find Miransky scaling as x -> x_c as well as Efimov-like saddle points. By calculating the holographic beta-functions, we demonstrate the "walking" behavior of the coupling in the region near and below x_c.
1607.03773
Ulrich Haisch
Martin Gorbahn and Ulrich Haisch
Indirect probes of the trilinear Higgs coupling: $gg \to h$ and $h \to \gamma \gamma$
17 pages, 5 figures
null
10.1007/JHEP10(2016)094
LTH 1092, CERN-TH-2016-161
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the framework of the Standard Model effective field theory, we examine the indirect constraints on the trilinear Higgs coupling $\lambda$ that arise from Higgs production in gluon-gluon-fusion and diphoton Higgs decays. We calculate 2-loop contributions to the $gg \to h$ and $h \to \gamma \gamma$ amplitudes that are affected by modifications of the trilinear Higgs-boson vertex. This calculation involves both the computation of anomalous dimensions and finite matching corrections. Based on our new results, we analyse the sensitivity of present and future measurements of the $hgg$ and $h \gamma \gamma$ couplings to shifts in $\lambda$. Under the assumption that $O_6 = - \lambda \left (H^\dagger H \right )^3$ is the only dimension-6 operator that alters the trilinear Higgs interactions, we find that at present the considered loop-level probes provide stronger constraints than $pp \to 2h$. At future high-energy colliders indirect ${\cal O} (5)$ determinations of the trilinear Higgs coupling may be possible, making precision measurements of $gg \to h$ and $h \to \gamma \gamma$ a useful addition to direct extractions of $\lambda$ through double-Higgs production.
[ { "created": "Wed, 13 Jul 2016 14:39:20 GMT", "version": "v1" } ]
2016-11-23
[ [ "Gorbahn", "Martin", "" ], [ "Haisch", "Ulrich", "" ] ]
In the framework of the Standard Model effective field theory, we examine the indirect constraints on the trilinear Higgs coupling $\lambda$ that arise from Higgs production in gluon-gluon-fusion and diphoton Higgs decays. We calculate 2-loop contributions to the $gg \to h$ and $h \to \gamma \gamma$ amplitudes that are affected by modifications of the trilinear Higgs-boson vertex. This calculation involves both the computation of anomalous dimensions and finite matching corrections. Based on our new results, we analyse the sensitivity of present and future measurements of the $hgg$ and $h \gamma \gamma$ couplings to shifts in $\lambda$. Under the assumption that $O_6 = - \lambda \left (H^\dagger H \right )^3$ is the only dimension-6 operator that alters the trilinear Higgs interactions, we find that at present the considered loop-level probes provide stronger constraints than $pp \to 2h$. At future high-energy colliders indirect ${\cal O} (5)$ determinations of the trilinear Higgs coupling may be possible, making precision measurements of $gg \to h$ and $h \to \gamma \gamma$ a useful addition to direct extractions of $\lambda$ through double-Higgs production.
0710.1540
Dmitri Antonov
D. Antonov, H.-J. Pirner
Jet quenching parameter \hat q in the stochastic QCD vacuum with Landau damping
20 pages, 6 figures, discussions and references added; final version to appear in Eur. Phys. J. C
Eur.Phys.J.C55:439-447,2008
10.1140/epjc/s10052-008-0599-1
null
hep-ph
null
We argue that the radiative energy loss of a parton traversing the quark-gluon plasma is determined by Landau damping of soft modes in the plasma. Using this idea, we calculate the jet quenching parameter of a gluon. The calculation is done in SU(3) quenched QCD within the stochastic vacuum model. At the LHC-relevant temperatures, the result depends on the gluon condensate, the vacuum correlation length, and the gluon Debye mass. Numerically, when the temperature varies from T=T_c to T=900 MeV, the jet quenching parameter rises from \hat q=0 to approximately 1.8 GeV^2/fm. We compare our results with the predictions of perturbative QCD and other calculations.
[ { "created": "Mon, 8 Oct 2007 14:54:56 GMT", "version": "v1" }, { "created": "Tue, 1 Apr 2008 08:58:26 GMT", "version": "v2" } ]
2008-11-26
[ [ "Antonov", "D.", "" ], [ "Pirner", "H. -J.", "" ] ]
We argue that the radiative energy loss of a parton traversing the quark-gluon plasma is determined by Landau damping of soft modes in the plasma. Using this idea, we calculate the jet quenching parameter of a gluon. The calculation is done in SU(3) quenched QCD within the stochastic vacuum model. At the LHC-relevant temperatures, the result depends on the gluon condensate, the vacuum correlation length, and the gluon Debye mass. Numerically, when the temperature varies from T=T_c to T=900 MeV, the jet quenching parameter rises from \hat q=0 to approximately 1.8 GeV^2/fm. We compare our results with the predictions of perturbative QCD and other calculations.
1003.2436
Berndt Muller
Masayuki Asakawa, Abhijit Majumder, and Berndt M\"uller
Electric Charge Separation in Strong Transient Magnetic Fields
null
Phys.Rev.C81:064912,2010
10.1103/PhysRevC.81.064912
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss various mechanisms for the creation of an asymmetric charge fluctuation with respect to the reaction plane among hadrons emitted in relativistic heavy-ion collisions. We show that such mechanisms exist in both, the hadronic gas and the partonic phases of QCD. The mechanisms considered here all require the presence of a strong magnetic field (the ``chiral magnetic effect''), but they do not involve parity or charge-parity violations. We analyze how a transient local electric current fluctuation generated by the chiral magnetic effect can dynamically evolve into an asymmetric charge distribution among the final-state hadrons in momentum space. We estimate the magnitude of the event-by-event fluctuations of the final-state charge asymmetry due to the partonic and hadronic mechanisms.
[ { "created": "Thu, 11 Mar 2010 22:11:04 GMT", "version": "v1" }, { "created": "Fri, 19 Mar 2010 02:41:22 GMT", "version": "v2" }, { "created": "Thu, 10 Jun 2010 00:19:04 GMT", "version": "v3" } ]
2015-03-13
[ [ "Asakawa", "Masayuki", "" ], [ "Majumder", "Abhijit", "" ], [ "Müller", "Berndt", "" ] ]
We discuss various mechanisms for the creation of an asymmetric charge fluctuation with respect to the reaction plane among hadrons emitted in relativistic heavy-ion collisions. We show that such mechanisms exist in both, the hadronic gas and the partonic phases of QCD. The mechanisms considered here all require the presence of a strong magnetic field (the ``chiral magnetic effect''), but they do not involve parity or charge-parity violations. We analyze how a transient local electric current fluctuation generated by the chiral magnetic effect can dynamically evolve into an asymmetric charge distribution among the final-state hadrons in momentum space. We estimate the magnitude of the event-by-event fluctuations of the final-state charge asymmetry due to the partonic and hadronic mechanisms.
hep-ph/9503258
Ed Stoeffhaas
V. Barger, M.S. Berger, K. Fujii, J.F. Gunion, T. Han, C. Heusch, W. Hong, S.K. Oh, Z. Parsa, S. Rajpoot, R. Thun, and B. Willis
Physics Goals of a $\mu^+\mu^-$ Collider
Report of Physics Goals Working Group presented by V. Barger at the 2nd Workshop on Physics Potential and Development of $\mu^+\mu^-$ Colliders, Sausalito, California, Nov.~1994. Latex file, 15 pages, uses epsf.sty to place 11 postscript figures. Compressed postscript version at ftp://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-873.ps.Z or at http://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-873.ps.Z
AIP Conf.Proc.352:55-69,1996
null
MADPH-95-873
hep-ph
null
This working group report focuses on the physics potential of $\mu^+\mu^-$ colliders beyond what can be accomplished at linear $e^+e^-$ colliders and the LHC. Particularly interesting possibilities include (i)~$s$-channel resonance production to discover and study heavy Higgs bosons with $ZZ$ and $WW$ couplings that are suppressed or absent at tree-level (such as the $H$ and $A$ Higgs bosons of supersymmetric models), (ii)~study of the strongly interacting electroweak sector, where higher energies give larger signals, and (iii)~measurements of the masses and properties of heavy supersymmetric particles.
[ { "created": "Tue, 7 Mar 1995 17:45:00 GMT", "version": "v1" } ]
2016-09-01
[ [ "Barger", "V.", "" ], [ "Berger", "M. S.", "" ], [ "Fujii", "K.", "" ], [ "Gunion", "J. F.", "" ], [ "Han", "T.", "" ], [ "Heusch", "C.", "" ], [ "Hong", "W.", "" ], [ "Oh", "S. K.", "" ], [ "Parsa", "Z.", "" ], [ "Rajpoot", "S.", "" ], [ "Thun", "R.", "" ], [ "Willis", "B.", "" ] ]
This working group report focuses on the physics potential of $\mu^+\mu^-$ colliders beyond what can be accomplished at linear $e^+e^-$ colliders and the LHC. Particularly interesting possibilities include (i)~$s$-channel resonance production to discover and study heavy Higgs bosons with $ZZ$ and $WW$ couplings that are suppressed or absent at tree-level (such as the $H$ and $A$ Higgs bosons of supersymmetric models), (ii)~study of the strongly interacting electroweak sector, where higher energies give larger signals, and (iii)~measurements of the masses and properties of heavy supersymmetric particles.
1812.07585
Adam Ritz
Anthony Fradette, Maxim Pospelov, Josef Pradler, Adam Ritz
Cosmological beam dump: constraints on dark scalars mixed with the Higgs boson
23 pages, 14 figures
Phys. Rev. D 99, 075004 (2019)
10.1103/PhysRevD.99.075004
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Precision cosmology provides a sensitive probe of extremely weakly coupled states due to thermal freeze-in production, with subsequent decays impacting physics during well-tested cosmological epochs. We explore the cosmological implications of the freeze-in production of a new scalar $S$ via the super-renormalizable Higgs portal. If the mass of $S$ is at or below the electroweak scale, peak freeze-in production occurs during the electroweak epoch. We improve the calculation of the freeze-in abundance by including all relevant QCD and electroweak production channels. The resulting abundance and subsequent decay of $S$ is constrained by a combination of X-ray data, cosmic microwave background anisotropies and spectral distortions, $N_{\rm eff}$, and the consistency of BBN with observations. These probes constrain technically natural couplings for such scalars from $m_S \sim$ keV all the way to $m_S \sim 100$ GeV. The ensuing constraints are similar in spirit to typical beam bump limits, but extend to much smaller couplings, down to mixing angles as small as $\theta_{Sh} \sim 10^{-16}$, and to masses all the way to the electroweak scale.
[ { "created": "Tue, 18 Dec 2018 19:00:06 GMT", "version": "v1" } ]
2019-04-10
[ [ "Fradette", "Anthony", "" ], [ "Pospelov", "Maxim", "" ], [ "Pradler", "Josef", "" ], [ "Ritz", "Adam", "" ] ]
Precision cosmology provides a sensitive probe of extremely weakly coupled states due to thermal freeze-in production, with subsequent decays impacting physics during well-tested cosmological epochs. We explore the cosmological implications of the freeze-in production of a new scalar $S$ via the super-renormalizable Higgs portal. If the mass of $S$ is at or below the electroweak scale, peak freeze-in production occurs during the electroweak epoch. We improve the calculation of the freeze-in abundance by including all relevant QCD and electroweak production channels. The resulting abundance and subsequent decay of $S$ is constrained by a combination of X-ray data, cosmic microwave background anisotropies and spectral distortions, $N_{\rm eff}$, and the consistency of BBN with observations. These probes constrain technically natural couplings for such scalars from $m_S \sim$ keV all the way to $m_S \sim 100$ GeV. The ensuing constraints are similar in spirit to typical beam bump limits, but extend to much smaller couplings, down to mixing angles as small as $\theta_{Sh} \sim 10^{-16}$, and to masses all the way to the electroweak scale.
0805.1989
Taewon Kim
Hee Sok Chung, Taewon Kim, and Jungil Lee (Korea U.)
Invariant-mass distribution of cc-bar in Upsilon(1S) -> cc-bar + X
15 pages, 1 figure
Phys.Rev.D78:114027,2008
10.1103/PhysRevD.78.114027
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We calculate the invariant-mass distribution for the cc-bar pair produced in the inclusive Upsilon(1S) decay based on the color-singlet mechanism of the nonrelativistic quantum chromodynamics factorization approach at leading order in the bottom-quark velocity v_b in the meson rest frame. As the short-distance processes, we consider bb-bar -> g^*gg followed by g^* -> cc-bar and bb-bar -> gamma^* -> cc-bar at leading order in the strong coupling. The invariant-mass distribution of the bb-bar -> cc-bar gg contribution has a sharp peak just above the threshold and that of the bb-bar -> gamma^* -> cc-bar channel is concentrated at the maximally allowed kinematic end point. We predict that Gamma[Upsilon(1S) -> cc-bar+X]/Gamma[Upsilon(1S)->light hadrons] = 0.065 alpha_s, which is smaller than a previous result by about 20%.
[ { "created": "Wed, 14 May 2008 07:40:32 GMT", "version": "v1" } ]
2009-01-08
[ [ "Chung", "Hee Sok", "", "Korea U." ], [ "Kim", "Taewon", "", "Korea U." ], [ "Lee", "Jungil", "", "Korea U." ] ]
We calculate the invariant-mass distribution for the cc-bar pair produced in the inclusive Upsilon(1S) decay based on the color-singlet mechanism of the nonrelativistic quantum chromodynamics factorization approach at leading order in the bottom-quark velocity v_b in the meson rest frame. As the short-distance processes, we consider bb-bar -> g^*gg followed by g^* -> cc-bar and bb-bar -> gamma^* -> cc-bar at leading order in the strong coupling. The invariant-mass distribution of the bb-bar -> cc-bar gg contribution has a sharp peak just above the threshold and that of the bb-bar -> gamma^* -> cc-bar channel is concentrated at the maximally allowed kinematic end point. We predict that Gamma[Upsilon(1S) -> cc-bar+X]/Gamma[Upsilon(1S)->light hadrons] = 0.065 alpha_s, which is smaller than a previous result by about 20%.
0706.0781
Robert Sch\"ofbeck
R. Schofbeck, H. Eberl
Two-loop SUSY QCD corrections to the chargino masses in the MSSM
12 pages, 11 figures, references modified, clarifications added
Eur.Phys.J.C53:621-626,2008
10.1140/epjc/s10052-007-0477-2
null
hep-ph
null
We have calculated the two-loop strong interaction corrections to the chargino pole masses in the DRbar'-scheme in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters. We have performed a detailed numerical analysis for a particular point in the parameter space and found corrections of a few tenths of a percent. We provide a computer program which calculates chargino and neutralino masses with complex parameters including the one-loop corrections and all two-loop SQCD effects.
[ { "created": "Wed, 6 Jun 2007 08:58:03 GMT", "version": "v1" }, { "created": "Fri, 13 Jul 2007 09:00:19 GMT", "version": "v2" } ]
2008-11-26
[ [ "Schofbeck", "R.", "" ], [ "Eberl", "H.", "" ] ]
We have calculated the two-loop strong interaction corrections to the chargino pole masses in the DRbar'-scheme in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters. We have performed a detailed numerical analysis for a particular point in the parameter space and found corrections of a few tenths of a percent. We provide a computer program which calculates chargino and neutralino masses with complex parameters including the one-loop corrections and all two-loop SQCD effects.
1808.01931
Xinyang Wang
Xinyang Wang, Minghua Wei, Zhibin Li, Mei Huang
Quark matter under rotation in the NJL model with vector interaction
null
Phys. Rev. D 99, 016018 (2019)
10.1103/PhysRevD.99.016018
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the chiral phase transition of quark matter under rotation in two-flavor Nambu--Jona-Lasinio (NJL) model. It is found that, in the rotating frame, the angular velocity plays the similar role as the baryon chemical potential and suppresses the chiral condensate, thus the chiral phase transition shows a critical end point not only in the temperature-chemical potential $T-\mu$ plane, but also in the temperature-angular momentum $T-\omega$ plane. One interesting observation is that in the $T-\mu$ plane, the presence of the angular momentum only shifts down the critical temperature $T^E$ of the CEP and does not shift the critical chemical potential $\mu^E$, and in the $T-\omega$ plane, the increase of the chemical potential only shift down the critical temperature $T^E$ and does not change the critical angular momentum $\omega^E$. The phase structure in the $T-\mu$ plane is sensitive to the coupling strength in the vector channel, while the phase structure in $T-\omega$ plane is not. It is also observed that the rotating angular velocity suppresses the kurtosis of the baryon number fluctuations, while it enhances the pressure density, energy density, the specific heat and the sound velocity.
[ { "created": "Mon, 6 Aug 2018 14:36:34 GMT", "version": "v1" }, { "created": "Sat, 12 Jan 2019 01:11:39 GMT", "version": "v2" } ]
2019-02-06
[ [ "Wang", "Xinyang", "" ], [ "Wei", "Minghua", "" ], [ "Li", "Zhibin", "" ], [ "Huang", "Mei", "" ] ]
We study the chiral phase transition of quark matter under rotation in two-flavor Nambu--Jona-Lasinio (NJL) model. It is found that, in the rotating frame, the angular velocity plays the similar role as the baryon chemical potential and suppresses the chiral condensate, thus the chiral phase transition shows a critical end point not only in the temperature-chemical potential $T-\mu$ plane, but also in the temperature-angular momentum $T-\omega$ plane. One interesting observation is that in the $T-\mu$ plane, the presence of the angular momentum only shifts down the critical temperature $T^E$ of the CEP and does not shift the critical chemical potential $\mu^E$, and in the $T-\omega$ plane, the increase of the chemical potential only shift down the critical temperature $T^E$ and does not change the critical angular momentum $\omega^E$. The phase structure in the $T-\mu$ plane is sensitive to the coupling strength in the vector channel, while the phase structure in $T-\omega$ plane is not. It is also observed that the rotating angular velocity suppresses the kurtosis of the baryon number fluctuations, while it enhances the pressure density, energy density, the specific heat and the sound velocity.
1310.0018
Benjamin Fuks
Jorgen D'Hondt, Karen De Causmaecker, Benjamin Fuks, Alberto Mariotti, Kentarou Mawatari, Christoffer Petersson and Diego Redigolo
Multilepton signals of gauge mediated supersymmetry breaking at the LHC
7 pages, 6 figures, 1 table; version accepted by PLB
Phys.Lett. B731 (2014) 7
10.1016/j.physletb.2014.02.016
CERN-PH-TH/2013-229, DCPT/13/154, IPPP/13/77
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate multilepton LHC signals arising from electroweak processes involving sleptons. We consider the framework of general gauge mediated supersymmetry breaking, focusing on models where the low mass region of the superpartner spectrum consists of the three generations of charged sleptons and the nearly massless gravitino. We demonstrate how such models can provide an explanation for the anomalous four lepton events recently observed by the CMS collaboration, while satisfying other existing experimental constraints. The best fit to the CMS data is obtained for a selectron/smuon mass of around 145 GeV and a stau mass of around 90 GeV. These models also give rise to final states with more than four leptons, offering alternative channels in which they can be probed and we estimate the corresponding production rates at the LHC.
[ { "created": "Mon, 30 Sep 2013 20:00:03 GMT", "version": "v1" }, { "created": "Mon, 10 Feb 2014 08:16:54 GMT", "version": "v2" } ]
2014-02-25
[ [ "D'Hondt", "Jorgen", "" ], [ "De Causmaecker", "Karen", "" ], [ "Fuks", "Benjamin", "" ], [ "Mariotti", "Alberto", "" ], [ "Mawatari", "Kentarou", "" ], [ "Petersson", "Christoffer", "" ], [ "Redigolo", "Diego", "" ] ]
We investigate multilepton LHC signals arising from electroweak processes involving sleptons. We consider the framework of general gauge mediated supersymmetry breaking, focusing on models where the low mass region of the superpartner spectrum consists of the three generations of charged sleptons and the nearly massless gravitino. We demonstrate how such models can provide an explanation for the anomalous four lepton events recently observed by the CMS collaboration, while satisfying other existing experimental constraints. The best fit to the CMS data is obtained for a selectron/smuon mass of around 145 GeV and a stau mass of around 90 GeV. These models also give rise to final states with more than four leptons, offering alternative channels in which they can be probed and we estimate the corresponding production rates at the LHC.