id
stringlengths
9
14
submitter
stringlengths
1
56
authors
stringlengths
5
7.68k
title
stringlengths
3
299
comments
stringlengths
1
1.15k
journal-ref
stringlengths
9
298
doi
stringlengths
12
97
report-no
stringlengths
3
341
categories
stringclasses
869 values
license
stringclasses
9 values
orig_abstract
stringlengths
16
2.44k
versions
listlengths
1
39
update_date
stringlengths
10
10
authors_parsed
listlengths
1
565
abstract
stringlengths
13
2.44k
2007.12132
Ming Li
Alex Kovner, Eugene Levin, Ming Li and Michael Lublinsky
Reggeon Field Theory and Self Duality: Making Ends Meet
42 pages, 7 figures; revised version responding to referee report
null
10.1007/JHEP10(2020)185
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the question of unitarity of Reggeon Field Theory, we use the effective field theory philosophy to find possible Reggeon Field Theory Hamiltonians $H_{RFT}$. We require that $H_{RFT}$ is self dual, reproduce all known limits (dilute-dense and dilute-dilute) and exhibits all the symmetries of the JIMWLK Hamiltonian. We find a family of Hamiltonians which satisfy all the above requirements. One of these is identical in form to the so called "diamond action" discussed in \cite{diamond,Balitsky05}. However we show by explicit calculation that the so called "diamond condition" is not satisfied beyond leading perturbative order.
[ { "created": "Thu, 23 Jul 2020 17:03:46 GMT", "version": "v1" }, { "created": "Wed, 9 Sep 2020 15:49:22 GMT", "version": "v2" } ]
2020-12-02
[ [ "Kovner", "Alex", "" ], [ "Levin", "Eugene", "" ], [ "Li", "Ming", "" ], [ "Lublinsky", "Michael", "" ] ]
Motivated by the question of unitarity of Reggeon Field Theory, we use the effective field theory philosophy to find possible Reggeon Field Theory Hamiltonians $H_{RFT}$. We require that $H_{RFT}$ is self dual, reproduce all known limits (dilute-dense and dilute-dilute) and exhibits all the symmetries of the JIMWLK Hamiltonian. We find a family of Hamiltonians which satisfy all the above requirements. One of these is identical in form to the so called "diamond action" discussed in \cite{diamond,Balitsky05}. However we show by explicit calculation that the so called "diamond condition" is not satisfied beyond leading perturbative order.
2009.12970
Maien Binjonaid
Marwa Telba, Maien Binjonaid
Impact of LHC Higgs couplings measurements on bosonic decays of the neutral Higgs sector in the scNMSSM
MPLA accepted version
null
10.1142/S0217732321500358
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the Next-to-minimal supersymmetric standard model with Grand unification boundary conditions under current theoretical and experimental constraints. We compute the mass spectrum of the model and focus on the three lightest particles in the Higgs sector (two CP-even scalars, $h_1, h_2$, and one CP-odd, $a_1$). The reduced couplings of such particles, singlet-doublet components, their branching ratios to bosons, and reduced cross-section to photons and massive gauge bosons via gluon fusion are thoroughly and systematically scrutinized. Our analysis is focused on the parameter space where the singlet-doublet coupling $\lambda$ is as large as possible (keeping the perturbativity bound intact) and the ratio between the vacuum expectation values of the up-type and down-type Higgses ($\tan{\beta}$) is as small as possible, which is the region representing the most natural case of the NMSSM. We show the impact of recent constraints from the LHC on the SM-Higgs couplings to bosons and fermions on the parameter space of the model and the consequent implications on the Higgs sector. The results show that while the model is still able to account for current data and provide an opportunity for discovery of extended Higgs sectors, recent LHC Higgs couplings constraints rule-out parts of the parameter space where $h_2$ (non-SM-like) and $a_1$ are non-singlet with masses below ~400 GeV.
[ { "created": "Sun, 27 Sep 2020 22:22:02 GMT", "version": "v1" }, { "created": "Wed, 30 Sep 2020 05:02:08 GMT", "version": "v2" }, { "created": "Thu, 7 Jan 2021 20:08:14 GMT", "version": "v3" } ]
2021-01-11
[ [ "Telba", "Marwa", "" ], [ "Binjonaid", "Maien", "" ] ]
We analyze the Next-to-minimal supersymmetric standard model with Grand unification boundary conditions under current theoretical and experimental constraints. We compute the mass spectrum of the model and focus on the three lightest particles in the Higgs sector (two CP-even scalars, $h_1, h_2$, and one CP-odd, $a_1$). The reduced couplings of such particles, singlet-doublet components, their branching ratios to bosons, and reduced cross-section to photons and massive gauge bosons via gluon fusion are thoroughly and systematically scrutinized. Our analysis is focused on the parameter space where the singlet-doublet coupling $\lambda$ is as large as possible (keeping the perturbativity bound intact) and the ratio between the vacuum expectation values of the up-type and down-type Higgses ($\tan{\beta}$) is as small as possible, which is the region representing the most natural case of the NMSSM. We show the impact of recent constraints from the LHC on the SM-Higgs couplings to bosons and fermions on the parameter space of the model and the consequent implications on the Higgs sector. The results show that while the model is still able to account for current data and provide an opportunity for discovery of extended Higgs sectors, recent LHC Higgs couplings constraints rule-out parts of the parameter space where $h_2$ (non-SM-like) and $a_1$ are non-singlet with masses below ~400 GeV.
2010.04471
Mathew Thomas Mr.
Giancarlo D'Ambrosio, Mathew Thomas Arun, Ashwani Kushwaha and Sudhir K. Vempati
Taming the $\epsilon_K$ in Little Randall Sundrum Models
22 pages, 6 figures, Accepted to be published in Physical Review D
Phys. Rev. D 104, 055012 (2021)
10.1103/PhysRevD.104.055012
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Randall Sundrum (RS) models receive significant constraints from the neutral Kaon system. The CP violating observable $\epsilon_K$, in Randall Sundrum scenario, requires the lightest KK gluon to be heavier than $\sim$ 24 TeV. The constraint is even stronger in the Little Randall Sundrum models (LRS), $\gtrsim$ 32 TeV. The LRS models are motivated for their possible visibility at the Large Hardon Collider (LHC). We show that the stringent constraints from K-physics can be relaxed in the LRS models, in the presence of the Brane Localised Kinetic Terms (BLKT). In particular, for a range of values, a UV BLKT could significantly modify the lightest KK gluon wave function such that the limit can reduces to 5 TeV. We also show that such a relaxation of the constraints can also be achieved by imposing flavour symmetries {\`a la } Minimal Flavour Protection.
[ { "created": "Fri, 9 Oct 2020 09:53:38 GMT", "version": "v1" }, { "created": "Fri, 6 Aug 2021 10:50:23 GMT", "version": "v2" } ]
2021-09-15
[ [ "D'Ambrosio", "Giancarlo", "" ], [ "Arun", "Mathew Thomas", "" ], [ "Kushwaha", "Ashwani", "" ], [ "Vempati", "Sudhir K.", "" ] ]
The Randall Sundrum (RS) models receive significant constraints from the neutral Kaon system. The CP violating observable $\epsilon_K$, in Randall Sundrum scenario, requires the lightest KK gluon to be heavier than $\sim$ 24 TeV. The constraint is even stronger in the Little Randall Sundrum models (LRS), $\gtrsim$ 32 TeV. The LRS models are motivated for their possible visibility at the Large Hardon Collider (LHC). We show that the stringent constraints from K-physics can be relaxed in the LRS models, in the presence of the Brane Localised Kinetic Terms (BLKT). In particular, for a range of values, a UV BLKT could significantly modify the lightest KK gluon wave function such that the limit can reduces to 5 TeV. We also show that such a relaxation of the constraints can also be achieved by imposing flavour symmetries {\`a la } Minimal Flavour Protection.
hep-ph/9906436
Asher Gotsman
E. Gotsman (Tel Aviv U.)
What can we learn from the Caldwell plot?
3 pages, 4 figures in eps files
null
null
TAUP 2515-99
hep-ph
null
We show that when screening corrections are included $ \frac{\partial F_{2}(x,Q^{2})}{\partial \ln Q^{2}}$ is consistent with the behaviour that one expects in pQCD. Screening corrections explain the enigma of the Caldwell plot.
[ { "created": "Mon, 21 Jun 1999 12:43:59 GMT", "version": "v1" } ]
2007-05-23
[ [ "Gotsman", "E.", "", "Tel Aviv U." ] ]
We show that when screening corrections are included $ \frac{\partial F_{2}(x,Q^{2})}{\partial \ln Q^{2}}$ is consistent with the behaviour that one expects in pQCD. Screening corrections explain the enigma of the Caldwell plot.
hep-ph/9510403
Pietro Santorelli
P. Colangelo, F. De Fazio, P. Santorelli and E. Scrimieri
QCD Sum Rule Analysis of the Decays $B \to K \ell^+ \ell^-$ and $B \to K^* \ell^+ \ell^-$
26 pages REVTEX + 7 figures. Some typos corrected, figure 5 and 7 modified. This version will appear on Physical Review D
Phys.Rev.D53:3672-3686,1996; Erratum-ibid.D57:3186,1998
10.1103/PhysRevD.53.3672 10.1103/PhysRevD.57.3186
BARI-TH/95-206, DSF-T-95/42
hep-ph
null
We use QCD sum rules to calculate the hadronic matrix elements governing the rare decays $B \to K \ell^+ \ell^-$ and $B \to K^* \ell^+ \ell^-$ induced by the flavour changing neutral current $b \to s$ transition. We also study relations among semileptonic and rare $B \to K^{(*)}$ decay form factors. The analysis of the invariant mass distribution of the lepton pair in $B \to K^{(*)} \ell^+ \ell^-$ and of the angular asymmetry in $B \to K^* \ell^+ \ell^-$ provides us with interesting tests of the Standard Model and its extensions.
[ { "created": "Wed, 25 Oct 1995 12:47:11 GMT", "version": "v1" }, { "created": "Thu, 11 Jan 1996 18:37:29 GMT", "version": "v2" } ]
2014-11-17
[ [ "Colangelo", "P.", "" ], [ "De Fazio", "F.", "" ], [ "Santorelli", "P.", "" ], [ "Scrimieri", "E.", "" ] ]
We use QCD sum rules to calculate the hadronic matrix elements governing the rare decays $B \to K \ell^+ \ell^-$ and $B \to K^* \ell^+ \ell^-$ induced by the flavour changing neutral current $b \to s$ transition. We also study relations among semileptonic and rare $B \to K^{(*)}$ decay form factors. The analysis of the invariant mass distribution of the lepton pair in $B \to K^{(*)} \ell^+ \ell^-$ and of the angular asymmetry in $B \to K^* \ell^+ \ell^-$ provides us with interesting tests of the Standard Model and its extensions.
1503.00735
Tobias Huber
Tobias Huber, Susanne Krankl (Siegen U.)
Two-loop master integrals for non-leptonic heavy-to-heavy decays
31 pages, 3 figures. v2: Minor modifications (typos etc.), matches published version
JHEP 1504 (2015) 140
10.1007/JHEP04(2015)140
SI-HEP-2015-09, QFET-2015-10
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the two-loop master integrals for non-leptonic heavy-to-heavy decays analytically in a recently-proposed canonical basis. For this genuine two-loop, two-scale problem we first derive a basis for the master integrals that disentangles the kinematics from the space-time dimension in the differential equations, and subsequently solve the latter in terms of iterated integrals up to weight four. The solution constitutes another valuable example of the finding of a canonical basis for two-loop master integrals that have two different internal masses, and assumes a form that is ideally suited for a subsequent convolution with the light-cone distribution amplitude in the framework of QCD factorisation.
[ { "created": "Mon, 2 Mar 2015 21:00:57 GMT", "version": "v1" }, { "created": "Tue, 28 Apr 2015 09:19:05 GMT", "version": "v2" } ]
2015-05-20
[ [ "Huber", "Tobias", "", "Siegen U." ], [ "Krankl", "Susanne", "", "Siegen U." ] ]
We compute the two-loop master integrals for non-leptonic heavy-to-heavy decays analytically in a recently-proposed canonical basis. For this genuine two-loop, two-scale problem we first derive a basis for the master integrals that disentangles the kinematics from the space-time dimension in the differential equations, and subsequently solve the latter in terms of iterated integrals up to weight four. The solution constitutes another valuable example of the finding of a canonical basis for two-loop master integrals that have two different internal masses, and assumes a form that is ideally suited for a subsequent convolution with the light-cone distribution amplitude in the framework of QCD factorisation.
hep-ph/0601062
Gudrun Heinrich
G. Heinrich
Towards e+e- --> 3 jets at NNLO by sector decomposition
14 pages, 4 figures
Eur.Phys.J.C48:25-33,2006
10.1140/epjc/s2006-02612-9
ZU-TH 02/06
hep-ph
null
A method based on sector decomposition has been developed to calculate the double real radiation part of the process e+e- to 3 jets at next-to-next-to-leading order. It is shown in an example that the numerical cancellation of soft and collinear poles works well. The method is flexible to include an arbitrary measurement function in the final Monte Carlo program, such that it allows to obtain differential distributions for different kinds of observables. This is demonstrated by showing 3-, 4- and 5-jet rates at order alpha_s^3 for a subpart of the process.
[ { "created": "Mon, 9 Jan 2006 18:27:35 GMT", "version": "v1" }, { "created": "Mon, 9 Jan 2006 22:21:03 GMT", "version": "v2" } ]
2009-01-07
[ [ "Heinrich", "G.", "" ] ]
A method based on sector decomposition has been developed to calculate the double real radiation part of the process e+e- to 3 jets at next-to-next-to-leading order. It is shown in an example that the numerical cancellation of soft and collinear poles works well. The method is flexible to include an arbitrary measurement function in the final Monte Carlo program, such that it allows to obtain differential distributions for different kinds of observables. This is demonstrated by showing 3-, 4- and 5-jet rates at order alpha_s^3 for a subpart of the process.
1107.5438
Debasish Borah
Debasish Borah, Urjit A. Yajnik
Spontaneous parity breaking and supersymmetry breaking in metastable vacua with consistent cosmology
14 pages, Journal version
JHEP 1112:072,2011
10.1007/JHEP12(2011)072
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the compatibility of spontaneous breaking of parity and successful cosmology in a left-right symmetric model where supersymmetry breaking is achieved in metastable vacua. We show that domain walls formed due to this breaking can be removed due to Planck scale suppressed terms, provided the parity breaking scale $M_R$ is constrained to remain smaller than $10^{10}-10^{11}$ GeV. Ensuring metastability is achieved naturally even if the entire mechanism operates at low scales, within a few orders of magnitude of the TeV scale. Taking $M_R$ as high as permitted, close to the acceptable reheat temperature after inflation, would require the magnetic phase of the Supersymmetric Quantum Chromodynamics (SQCD) to have set in before the end of inflation.
[ { "created": "Wed, 27 Jul 2011 11:02:38 GMT", "version": "v1" }, { "created": "Fri, 6 Jan 2012 08:19:21 GMT", "version": "v2" } ]
2012-01-09
[ [ "Borah", "Debasish", "" ], [ "Yajnik", "Urjit A.", "" ] ]
We study the compatibility of spontaneous breaking of parity and successful cosmology in a left-right symmetric model where supersymmetry breaking is achieved in metastable vacua. We show that domain walls formed due to this breaking can be removed due to Planck scale suppressed terms, provided the parity breaking scale $M_R$ is constrained to remain smaller than $10^{10}-10^{11}$ GeV. Ensuring metastability is achieved naturally even if the entire mechanism operates at low scales, within a few orders of magnitude of the TeV scale. Taking $M_R$ as high as permitted, close to the acceptable reheat temperature after inflation, would require the magnetic phase of the Supersymmetric Quantum Chromodynamics (SQCD) to have set in before the end of inflation.
1702.01527
Yoshihiro Shigekami
Nobuhiro Maekawa, Yu Muramatsu and Yoshihiro Shigekami
Constraints of chromoelectric dipole moments to natural SUSY type sfermion spectrum
22 pages, 9 figures, v3: texts are improved, comments are added, v4: texts are improved
Phys. Rev. D 95, 115021 (2017)
10.1103/PhysRevD.95.115021
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the lower bounds of sfermion masses from the constraints of chromoelectric dipole moments (CEDMs) in the natural SUSY-type sfermion mass spectrum, in which stop mass $m_{\tilde t}$ is much smaller than the other sfermion masses $m_0$. The natural SUSY-type sfermion mass spectrum has been studied since the supersymmetric (SUSY) flavor-changing neutral currents (FCNC) are suppressed because of large sfermion masses of the first two generations, and the weak scale is stabilized because of the light stop. However, this type of sfermion mass spectrum is severely constrained by CEDM, because the light stop contributions to the up quark CEDM are not decoupled in the limit $m_0\rightarrow\infty$, while the down quark CEDM is decoupled in the limit. It is important that the constraints are severe even if SUSY-breaking parameters (and Higgsino mass) are taken to be real because complex diagonalizing matrices of Yukawa matrices, which are from complex Yukawa couplings, generate nonvanishing CP phases in off-diagonal elements of sfermion mass matrices. We calculate the CEDM of up and down quarks numerically in the minimal SUSY standard model, and give the lower bounds for stop mass and the other sfermion masses. We show that the lower bound of stop mass becomes 7 TeV to satisfy the CEDM constraints from Hg EDM. The result is not acceptable if the weak scale stability is considered seriously. We show that if the up-type Yukawa couplings are taken to be real at the grand unification scale, the CEDM constraints are satisfied even if $m_{\tilde t}\sim 1$ TeV.
[ { "created": "Mon, 6 Feb 2017 08:20:50 GMT", "version": "v1" }, { "created": "Thu, 23 Feb 2017 08:17:55 GMT", "version": "v2" }, { "created": "Fri, 14 Apr 2017 02:55:06 GMT", "version": "v3" }, { "created": "Mon, 19 Jun 2017 09:26:19 GMT", "version": "v4" } ]
2017-06-20
[ [ "Maekawa", "Nobuhiro", "" ], [ "Muramatsu", "Yu", "" ], [ "Shigekami", "Yoshihiro", "" ] ]
We investigate the lower bounds of sfermion masses from the constraints of chromoelectric dipole moments (CEDMs) in the natural SUSY-type sfermion mass spectrum, in which stop mass $m_{\tilde t}$ is much smaller than the other sfermion masses $m_0$. The natural SUSY-type sfermion mass spectrum has been studied since the supersymmetric (SUSY) flavor-changing neutral currents (FCNC) are suppressed because of large sfermion masses of the first two generations, and the weak scale is stabilized because of the light stop. However, this type of sfermion mass spectrum is severely constrained by CEDM, because the light stop contributions to the up quark CEDM are not decoupled in the limit $m_0\rightarrow\infty$, while the down quark CEDM is decoupled in the limit. It is important that the constraints are severe even if SUSY-breaking parameters (and Higgsino mass) are taken to be real because complex diagonalizing matrices of Yukawa matrices, which are from complex Yukawa couplings, generate nonvanishing CP phases in off-diagonal elements of sfermion mass matrices. We calculate the CEDM of up and down quarks numerically in the minimal SUSY standard model, and give the lower bounds for stop mass and the other sfermion masses. We show that the lower bound of stop mass becomes 7 TeV to satisfy the CEDM constraints from Hg EDM. The result is not acceptable if the weak scale stability is considered seriously. We show that if the up-type Yukawa couplings are taken to be real at the grand unification scale, the CEDM constraints are satisfied even if $m_{\tilde t}\sim 1$ TeV.
1809.09624
Mikael Chala
Mikael Chala, Jose Santiago and Michael Spannowsky
Constraining four-fermion operators using rare top decays
28 pages, 4 figures. V2: matches published version
null
10.1007/JHEP04(2019)014
IPPP/18/82
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
New physics can manifest itself by an appreciable increase of the decay rate of top quarks in rare flavour-changing final states. Exploiting the large top quark production rate at the LHC, we bound four-fermion operators contributing to non-resonant $t\rightarrow \ell^+\ell^- j$ using different signal regions of the latest LHC searches for $t\rightarrow Zj$. We also provide prospects for the high-luminosity LHC to test these as well as four-fermion operators contributing to $t\rightarrow b\overline{b}j$, based on improved analysis strategies of existing searches. We single out all weakly-coupled ultraviolet completions inducing such contact interactions at tree level and translate the previous bounds to the parameter space of specific complete models. Being above the TeV, LHC bounds from rare top decays improve over those from flavour physics, electroweak precision data and other LHC searches in several cases.
[ { "created": "Tue, 25 Sep 2018 18:00:00 GMT", "version": "v1" }, { "created": "Thu, 4 Apr 2019 13:19:27 GMT", "version": "v2" } ]
2019-05-01
[ [ "Chala", "Mikael", "" ], [ "Santiago", "Jose", "" ], [ "Spannowsky", "Michael", "" ] ]
New physics can manifest itself by an appreciable increase of the decay rate of top quarks in rare flavour-changing final states. Exploiting the large top quark production rate at the LHC, we bound four-fermion operators contributing to non-resonant $t\rightarrow \ell^+\ell^- j$ using different signal regions of the latest LHC searches for $t\rightarrow Zj$. We also provide prospects for the high-luminosity LHC to test these as well as four-fermion operators contributing to $t\rightarrow b\overline{b}j$, based on improved analysis strategies of existing searches. We single out all weakly-coupled ultraviolet completions inducing such contact interactions at tree level and translate the previous bounds to the parameter space of specific complete models. Being above the TeV, LHC bounds from rare top decays improve over those from flavour physics, electroweak precision data and other LHC searches in several cases.
1008.2984
Joshua Spitz
Janet Conrad, Andre de Gouvea, Shashank Shalgar and Joshua Spitz
Atmospheric Tau Neutrinos in a Multi-kiloton Liquid Argon Detector
14 pages, 11 figures
Phys.Rev.D82:093012,2010
10.1103/PhysRevD.82.093012
NUHEP-TH/10-11
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An ultra-large Liquid Argon Time Projection Chamber-based neutrino detector will have the uncommon ability to detect atmospheric tau neutrino events. This paper discusses the most promising modes for identifying charged current tau neutrino interactions, and shows that, with simple kinematic cuts, ~30 tau neutrinos can be isolated in a 100 kt*yr exposure, with greater than 4 sigma significance. This sample is sufficient to perform flux-averaged total cross-section and cross-section shape parameterization measurements -- the first steps toward using tau neutrinos to search for physics beyond the Standard Model.
[ { "created": "Tue, 17 Aug 2010 23:02:14 GMT", "version": "v1" }, { "created": "Tue, 24 Aug 2010 17:52:56 GMT", "version": "v2" } ]
2010-12-09
[ [ "Conrad", "Janet", "" ], [ "de Gouvea", "Andre", "" ], [ "Shalgar", "Shashank", "" ], [ "Spitz", "Joshua", "" ] ]
An ultra-large Liquid Argon Time Projection Chamber-based neutrino detector will have the uncommon ability to detect atmospheric tau neutrino events. This paper discusses the most promising modes for identifying charged current tau neutrino interactions, and shows that, with simple kinematic cuts, ~30 tau neutrinos can be isolated in a 100 kt*yr exposure, with greater than 4 sigma significance. This sample is sufficient to perform flux-averaged total cross-section and cross-section shape parameterization measurements -- the first steps toward using tau neutrinos to search for physics beyond the Standard Model.
0803.4405
Solveig Skadhauge
F. de Campos, M.A. Diaz, O.J.P. Eboli, M.B. Magro, W. Porod, S. Skadhauge
LHC signals for neutrino mass model in bilinear R-parity violating mAMSB
27 pages
Phys.Rev.D77:115025,2008
10.1103/PhysRevD.77.115025
Nordita-2008-13
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate a neutrino mass model in which the neutrino data is accounted for by bilinear R-parity violating supersymmetry with anomaly mediated supersymmetry breaking. We focus on the CERN Large Hadron Collider (LHC) phenomenology, studying the reach of generic supersymmetry search channels with leptons, missing energy and jets. A special feature of this model is the existence of long lived neutralinos and charginos which decay inside the detector leading to detached vertices. We demonstrate that the largest reach is obtained in the displaced vertices channel and that practically all of the reasonable parameter space will be covered with an integrated luminosity of 10 fb-1. We also compare the displaced vertex reaches of the LHC and Tevatron.
[ { "created": "Mon, 31 Mar 2008 09:06:27 GMT", "version": "v1" } ]
2008-11-26
[ [ "de Campos", "F.", "" ], [ "Diaz", "M. A.", "" ], [ "Eboli", "O. J. P.", "" ], [ "Magro", "M. B.", "" ], [ "Porod", "W.", "" ], [ "Skadhauge", "S.", "" ] ]
We investigate a neutrino mass model in which the neutrino data is accounted for by bilinear R-parity violating supersymmetry with anomaly mediated supersymmetry breaking. We focus on the CERN Large Hadron Collider (LHC) phenomenology, studying the reach of generic supersymmetry search channels with leptons, missing energy and jets. A special feature of this model is the existence of long lived neutralinos and charginos which decay inside the detector leading to detached vertices. We demonstrate that the largest reach is obtained in the displaced vertices channel and that practically all of the reasonable parameter space will be covered with an integrated luminosity of 10 fb-1. We also compare the displaced vertex reaches of the LHC and Tevatron.
1902.10746
Carlos Maldonado Salazar
Carlos Maldonado and James Unwin
Establishing the Dark Matter Relic Density in an Era of Particle Decays
v2. matches published version
null
10.1088/1475-7516/2019/06/037
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
If the early universe is dominated by an energy density which evolves other than radiation-like the normal Hubble-temperature relation $H\propto T^2$ is broken and dark matter relic density calculations in this era can be significantly different. We first highlight that for a population of states $\phi$ sourcing an initial expansion rate of the form $H\propto T^{2+n/2}$ for $n\geq-4$, during the period of appreciable $\phi$ decays the evolution transitions to $H\propto T^4$. The decays of $\phi$ imply a source of entropy production in the thermal bath which alters the Boltzmann equations and impacts the dark matter relic abundance. We show that the form of the initial expansion rate leaves a lasting imprint on relic densities established while $H\propto T^4$ since the value of the exponent $n$ changes the temperature evolution of the thermal bath. In particular, a dark matter relic density set via freeze-in or non-thermal production is highly sensitive to the temperature dependance of the initial expansion rate. This work generalises earlier studies which assumed initial expansion rates due to matter or kination domination.
[ { "created": "Wed, 27 Feb 2019 19:31:12 GMT", "version": "v1" }, { "created": "Tue, 4 Jun 2019 18:30:09 GMT", "version": "v2" } ]
2019-06-26
[ [ "Maldonado", "Carlos", "" ], [ "Unwin", "James", "" ] ]
If the early universe is dominated by an energy density which evolves other than radiation-like the normal Hubble-temperature relation $H\propto T^2$ is broken and dark matter relic density calculations in this era can be significantly different. We first highlight that for a population of states $\phi$ sourcing an initial expansion rate of the form $H\propto T^{2+n/2}$ for $n\geq-4$, during the period of appreciable $\phi$ decays the evolution transitions to $H\propto T^4$. The decays of $\phi$ imply a source of entropy production in the thermal bath which alters the Boltzmann equations and impacts the dark matter relic abundance. We show that the form of the initial expansion rate leaves a lasting imprint on relic densities established while $H\propto T^4$ since the value of the exponent $n$ changes the temperature evolution of the thermal bath. In particular, a dark matter relic density set via freeze-in or non-thermal production is highly sensitive to the temperature dependance of the initial expansion rate. This work generalises earlier studies which assumed initial expansion rates due to matter or kination domination.
hep-ph/9410288
null
Zenr\=o Hioki
Studying Structure of Electroweak Corrections
18 pages
Int.J.Mod.Phys. A10 (1995) 3803-3816
10.1142/S0217751X95001790
TUM-T31-80/94
hep-ph
null
Several different effects in electroweak quantum corrections are explored separately through the latest data on the weak-boson masses. The leading-log approximation, the improved-Born approximation and the non-decoupling top-quark effects are studied without depending on the recent CDF data of $m_t$, and the results are given in a form independent of the Higgs mass. On the other hand, the bosonic- and the non-decoupling Higgs effects are examined by fully taking account of those CDF data. It is emphasized that future precision measurements of $M_W$ and $m_t$ are considerably significant not only for further studies of the electroweak theory at higher confidence level but also for new physics searches beyond it.
[ { "created": "Fri, 14 Oct 1994 14:52:55 GMT", "version": "v1" } ]
2015-06-25
[ [ "Hioki", "Zenrō", "" ] ]
Several different effects in electroweak quantum corrections are explored separately through the latest data on the weak-boson masses. The leading-log approximation, the improved-Born approximation and the non-decoupling top-quark effects are studied without depending on the recent CDF data of $m_t$, and the results are given in a form independent of the Higgs mass. On the other hand, the bosonic- and the non-decoupling Higgs effects are examined by fully taking account of those CDF data. It is emphasized that future precision measurements of $M_W$ and $m_t$ are considerably significant not only for further studies of the electroweak theory at higher confidence level but also for new physics searches beyond it.
2405.07066
Halil Mutuk
Halil Mutuk, Xian-Wei Kang
Unveiling the Structure of Hidden-Bottom Strange Pentaquarks via Magnetic Moments
8 pages, III tables, Accepted in PLB
null
null
null
hep-ph hep-ex hep-lat nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
Motivated by the discovery of hidden-charm strange pentaquarks, we conduct a systematic study of the magnetic moments of the hidden-bottom strange pentaquarks in molecular picture. We calculate magnetic moments of hidden-bottom strange pentaquarks with strangeness-1 and 2. Magnetic moment gives valuable information about the inner structure and shape of the hadron. The obtained results may be helpful to determine the inner structure of these new yet hypothetical states.
[ { "created": "Sat, 11 May 2024 18:23:06 GMT", "version": "v1" }, { "created": "Wed, 5 Jun 2024 20:37:25 GMT", "version": "v2" } ]
2024-06-07
[ [ "Mutuk", "Halil", "" ], [ "Kang", "Xian-Wei", "" ] ]
Motivated by the discovery of hidden-charm strange pentaquarks, we conduct a systematic study of the magnetic moments of the hidden-bottom strange pentaquarks in molecular picture. We calculate magnetic moments of hidden-bottom strange pentaquarks with strangeness-1 and 2. Magnetic moment gives valuable information about the inner structure and shape of the hadron. The obtained results may be helpful to determine the inner structure of these new yet hypothetical states.
1104.0616
Carlos Falquez
Carlos Falquez
Investigation of Thermal Ground-State Effects in SU(2) Yang-Mills Thermodynamics
125 pages, 28 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate experimental consequences of the postulate that fundamentally photon propagation is governed by an SU(2) rather than a U(1) gauge principle. In the context of thermodynamics the SU(2) Yang-Mills theory is assumed to be in its deconfining phase. In addition to the results already available, we compute the dispersion law for the longitudinal mode, which does not thermalize with matter, at one-loop accuracy. We analyze radiometric and bolometric methods to detect a gap in the black-body radiation spectra for low frequencies and at low temperatures. We simulate the expected experimental results for total-power and Dicke-switch radiometry. These simulations indicate that the predicted SU(2) signature is measurable with presently available detector technology appealing to both radiometric methods. We also investigate non-homogeneous thermodynamics (thermomagnetic effect) in the adiabatic approximation.
[ { "created": "Mon, 4 Apr 2011 16:34:07 GMT", "version": "v1" } ]
2011-04-05
[ [ "Falquez", "Carlos", "" ] ]
We investigate experimental consequences of the postulate that fundamentally photon propagation is governed by an SU(2) rather than a U(1) gauge principle. In the context of thermodynamics the SU(2) Yang-Mills theory is assumed to be in its deconfining phase. In addition to the results already available, we compute the dispersion law for the longitudinal mode, which does not thermalize with matter, at one-loop accuracy. We analyze radiometric and bolometric methods to detect a gap in the black-body radiation spectra for low frequencies and at low temperatures. We simulate the expected experimental results for total-power and Dicke-switch radiometry. These simulations indicate that the predicted SU(2) signature is measurable with presently available detector technology appealing to both radiometric methods. We also investigate non-homogeneous thermodynamics (thermomagnetic effect) in the adiabatic approximation.
2308.05638
Edward Shuryak
Nicholas Miesch, Edward Shuryak, Ismail Zahed
Baryons and tetraquarks using instanton-induced interactions
null
null
null
null
hep-ph hep-lat
http://creativecommons.org/licenses/by/4.0/
We analyze some aspects of the perturbative and non-perturbative interactions in the composition of heavy quarkonia, heavy and light baryons ($ccc$ and $uuu$ ones), as well as all charm tetraquarks ($cc\bar c\bar c$). Using the hyper-spherical approximation and effective radial potentials (in 6 and 9 dimensions, respectively) we derive their spectra and wave functions. In all of the cases, we focus on the splittings between the s-shell levels, which are remarkably insensitive to the quark masses, but proportional to the effective interaction potentials. We use the traditional Cornell-like potentials, and the non-perturbative instanton-induced static potentials, from correlators of two, three and four Wilson lines, and find rather satisfactory description of spectra in all cases.
[ { "created": "Thu, 10 Aug 2023 15:29:03 GMT", "version": "v1" } ]
2023-08-11
[ [ "Miesch", "Nicholas", "" ], [ "Shuryak", "Edward", "" ], [ "Zahed", "Ismail", "" ] ]
We analyze some aspects of the perturbative and non-perturbative interactions in the composition of heavy quarkonia, heavy and light baryons ($ccc$ and $uuu$ ones), as well as all charm tetraquarks ($cc\bar c\bar c$). Using the hyper-spherical approximation and effective radial potentials (in 6 and 9 dimensions, respectively) we derive their spectra and wave functions. In all of the cases, we focus on the splittings between the s-shell levels, which are remarkably insensitive to the quark masses, but proportional to the effective interaction potentials. We use the traditional Cornell-like potentials, and the non-perturbative instanton-induced static potentials, from correlators of two, three and four Wilson lines, and find rather satisfactory description of spectra in all cases.
1711.01472
Kenji Fukushima
Kenji Fukushima, Yoshimasa Hidaka
Electric conductivity of hot and dense quark matter in a magnetic field with Landau level resummation via kinetic equations
5 pages, 5 figures
Phys. Rev. Lett. 120, 162301 (2018)
10.1103/PhysRevLett.120.162301
RIKEN-QHP-334, RIKEN-STAMP-37, RIKEN-iTHEMS-Report-17
hep-ph cond-mat.str-el
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the electric conductivity of quark matter at finite temperature $T$ and quark chemical potential $\mu$ under a magnetic field $B$ beyond the Lowest Landau level approximation. The electric conductivity transverse to $B$ is dominated by the Hall conductivity $\sigma_H$. For the longitudinal conductivity $\sigma_\parallel$, we need to solve kinetic equations. Then, we numerically find that $\sigma_\parallel$ has only mild dependence on $\mu$ and the quark mass $m_q$. Moreover, $\sigma_\parallel$ first decreases and then linearly increases as a function of $B$, leading to an intermediate $B$ region which looks consistent with the experimental signature for the chiral magnetic effect. We also point out that $\sigma_\parallel$ at nonzero $B$ remains within the range of the lattice-QCD estimate at $B=0$.
[ { "created": "Sat, 4 Nov 2017 18:24:15 GMT", "version": "v1" } ]
2018-04-25
[ [ "Fukushima", "Kenji", "" ], [ "Hidaka", "Yoshimasa", "" ] ]
We compute the electric conductivity of quark matter at finite temperature $T$ and quark chemical potential $\mu$ under a magnetic field $B$ beyond the Lowest Landau level approximation. The electric conductivity transverse to $B$ is dominated by the Hall conductivity $\sigma_H$. For the longitudinal conductivity $\sigma_\parallel$, we need to solve kinetic equations. Then, we numerically find that $\sigma_\parallel$ has only mild dependence on $\mu$ and the quark mass $m_q$. Moreover, $\sigma_\parallel$ first decreases and then linearly increases as a function of $B$, leading to an intermediate $B$ region which looks consistent with the experimental signature for the chiral magnetic effect. We also point out that $\sigma_\parallel$ at nonzero $B$ remains within the range of the lattice-QCD estimate at $B=0$.
hep-ph/0305038
Hai-Yang Cheng
Hai-Yang Cheng and Wei-Shu Hou
B Decays as Spectroscope for Charmed Four-quark States
6 pages and 2 figures
Phys.Lett.B566:193-200,2003
10.1016/S0370-2693(03)00834-7
null
hep-ph
null
The $D_s(2320)$ state recently observed by BaBar in the $D_s^+\pi^0$ channel may be the first of a host of $cq\bar q\bar q$ four-quark states. We give a phenomenological account of the masses and decay modes. The isosinglet $D_s(2320)$ state is the only narrow one, dominated by the observed isospin violating decay and less than $\sim$ 100 keV in width. All other states are expected to decay hadronically. Notable resonances are in doubly charged $D_s^+\pi^+$, $D^+K^+$, wrong pairing $D^+K^-$, and also $D_s^+K^-$, $D\eta$ channels. We propose B decays as searching ground for such 4-quark states, which recoil against $\bar D^{(*)}$ meson from B decay, or $\pi^+$ $\bar D^{(*)}$, $\bar K$ mesons from $\bar B$ decay. Exotic $qc\bar c\bar q$ charmonia could also be produced, and may be behind the slow $J/\psi$ bump in inclusive $B\to J/\psi+X$ decay.
[ { "created": "Mon, 5 May 2003 12:51:51 GMT", "version": "v1" } ]
2008-11-26
[ [ "Cheng", "Hai-Yang", "" ], [ "Hou", "Wei-Shu", "" ] ]
The $D_s(2320)$ state recently observed by BaBar in the $D_s^+\pi^0$ channel may be the first of a host of $cq\bar q\bar q$ four-quark states. We give a phenomenological account of the masses and decay modes. The isosinglet $D_s(2320)$ state is the only narrow one, dominated by the observed isospin violating decay and less than $\sim$ 100 keV in width. All other states are expected to decay hadronically. Notable resonances are in doubly charged $D_s^+\pi^+$, $D^+K^+$, wrong pairing $D^+K^-$, and also $D_s^+K^-$, $D\eta$ channels. We propose B decays as searching ground for such 4-quark states, which recoil against $\bar D^{(*)}$ meson from B decay, or $\pi^+$ $\bar D^{(*)}$, $\bar K$ mesons from $\bar B$ decay. Exotic $qc\bar c\bar q$ charmonia could also be produced, and may be behind the slow $J/\psi$ bump in inclusive $B\to J/\psi+X$ decay.
2210.01730
Anupam Ray
Anupam Ray
Mergers as a Probe of Particle Dark Matter
v2: 8 pages, 2 figures. Published in SciPost Physics Proceedings: 14th International Conference on Identification of Dark Matter (IDM) 2022
SciPost Phys. Proc. 12, 056 (2023)
10.21468/SciPostPhysProc.12.056
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Black holes below Chandrasekhar mass limit (1.4 $M_{\odot}$) can not be produced via any standard stellar evolution. Recently, gravitational wave experiments have also discovered unusually low mass black holes whose origin is yet to be known. We propose a simple yet novel formation mechanism of such low mass black holes. Non-annihilating particle dark matter, owing to their interaction with stellar nuclei, can gradually accumulate inside compact stars, and eventually swallows them to low mass black holes, ordinarily impermissible by the Chandrasekhar limit. We point out several avenues to test this proposal, concentrating on the cosmic evolution of the binary merger rates.
[ { "created": "Tue, 4 Oct 2022 16:42:09 GMT", "version": "v1" }, { "created": "Wed, 5 Jul 2023 15:55:37 GMT", "version": "v2" } ]
2023-07-06
[ [ "Ray", "Anupam", "" ] ]
Black holes below Chandrasekhar mass limit (1.4 $M_{\odot}$) can not be produced via any standard stellar evolution. Recently, gravitational wave experiments have also discovered unusually low mass black holes whose origin is yet to be known. We propose a simple yet novel formation mechanism of such low mass black holes. Non-annihilating particle dark matter, owing to their interaction with stellar nuclei, can gradually accumulate inside compact stars, and eventually swallows them to low mass black holes, ordinarily impermissible by the Chandrasekhar limit. We point out several avenues to test this proposal, concentrating on the cosmic evolution of the binary merger rates.
1904.07039
Kazuki Enomoto
Kazuki Enomoto, Shinya Kanemura, Kodai Sakurai, Hiroaki Sugiyama
New model for radiatively generated Dirac neutrino masses and lepton flavor violating decays of the Higgs boson
26 pages, 9 eps files
Phys. Rev. D 100, 015044 (2019)
10.1103/PhysRevD.100.015044
OU-HET 993, UT-HET 130
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a new mechanism to explain neutrino masses with lepton number conservation, in which the Dirac neutrino masses are generated at the two-loop level involving a dark matter candidate. In this model, branching ratios of lepton flavor violating decays of the Higgs boson can be much larger than those of lepton flavor violating decays of charged leptons. If lepton flavor violating decays of the Higgs boson are observed at future collider experiments without detecting lepton flavor violating decays of charged leptons, most of the models previously proposed for tiny neutrino masses are excluded while our model can still survive. We show that the model can be viable under constraints from current data for neutrino experiments, searches for lepton flavor violating decays of charged leptons and dark matter experiments.
[ { "created": "Mon, 15 Apr 2019 13:40:59 GMT", "version": "v1" } ]
2019-08-07
[ [ "Enomoto", "Kazuki", "" ], [ "Kanemura", "Shinya", "" ], [ "Sakurai", "Kodai", "" ], [ "Sugiyama", "Hiroaki", "" ] ]
We propose a new mechanism to explain neutrino masses with lepton number conservation, in which the Dirac neutrino masses are generated at the two-loop level involving a dark matter candidate. In this model, branching ratios of lepton flavor violating decays of the Higgs boson can be much larger than those of lepton flavor violating decays of charged leptons. If lepton flavor violating decays of the Higgs boson are observed at future collider experiments without detecting lepton flavor violating decays of charged leptons, most of the models previously proposed for tiny neutrino masses are excluded while our model can still survive. We show that the model can be viable under constraints from current data for neutrino experiments, searches for lepton flavor violating decays of charged leptons and dark matter experiments.
2203.04284
Tuomas Tenkanen
Philipp Schicho, Tuomas V. I. Tenkanen and Graham White
Combining thermal resummation and gauge invariance for electroweak phase transition
38 pages, 5 figures, no gauge dependence
null
10.1007/JHEP11(2022)047
HIP-2022-2/TH, NORDITA 2022-009
hep-ph
http://creativecommons.org/licenses/by/4.0/
For computing thermodynamics of the electroweak phase transition, we discuss a minimal approach that reconciles both gauge invariance and thermal resummation. Such a minimal setup consists of a two-loop dimensional reduction to three-dimensional effective theory, a one-loop computation of the effective potential and its expansion around the leading-order minima within the effective theory. This approach is tractable and provides formulae for resummation that are arguably no more complicated than those that appear in standard techniques ubiquitous in the literature. In particular, we implement renormalisation group improvement related to the hard thermal scale. Despite its generic nature, we present this approach for the complex singlet extension of the Standard Model which has interesting prospects for high energy collider phenomenology and dark matter predictions. The presented expressions can be used in future studies of phase transition thermodynamics and gravitational wave production.
[ { "created": "Tue, 8 Mar 2022 18:57:33 GMT", "version": "v1" } ]
2022-11-30
[ [ "Schicho", "Philipp", "" ], [ "Tenkanen", "Tuomas V. I.", "" ], [ "White", "Graham", "" ] ]
For computing thermodynamics of the electroweak phase transition, we discuss a minimal approach that reconciles both gauge invariance and thermal resummation. Such a minimal setup consists of a two-loop dimensional reduction to three-dimensional effective theory, a one-loop computation of the effective potential and its expansion around the leading-order minima within the effective theory. This approach is tractable and provides formulae for resummation that are arguably no more complicated than those that appear in standard techniques ubiquitous in the literature. In particular, we implement renormalisation group improvement related to the hard thermal scale. Despite its generic nature, we present this approach for the complex singlet extension of the Standard Model which has interesting prospects for high energy collider phenomenology and dark matter predictions. The presented expressions can be used in future studies of phase transition thermodynamics and gravitational wave production.
1306.2722
Dong Wang
Dong Wang and Yong Ban and Gang Li
$\rho - \omega$ Mixing in $J/\psi\to VP$ Decays
Submitted to Chinese Physics C (CPC). 8 pages, 3 figures (one of them with 5 subfigures), 3 tables
null
10.1088/1674-1137/38/6/063101
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study on $\rho-\omega$ mixing is mainly focused on vector mesons decay with isospin I=1, namely $\rho(\omega)\to\pi^+\pi^-$ process. In this paper, we present the study of $\rho-\omega$ mixing in $\rho(\omega)\to\pi^+\pi^-\pi^0$ (I=0) using a flavor parameterization model for $J/\psi\to VP$ process. By fitting theoretical frame to PDG data, we obtain the SU(3)-breaking effect parameters $s_V=0.03\pm 0.12,\ s_P=0.17\pm 0.17$ and the $\rho-\omega$ mixing polarization operator $\Pi_{\rho \omega}=0.006\pm 0.011\text{\text{GeV}}^2$. The branching ratios are also renewed when mixing effect is incorporated: $Br(J/\psi\to \omega\pi^0) = (3.64 \pm 0.37)\times 10^{-4}$, $Br(J/\psi\to \omega\eta) = (1.48 \pm 0.17)\times 10^{-3}$, $Br(J/\psi\to \omega\eta^{\prime}) = (1.55\pm 0.56)\times 10^{-4}$; they are different from the corresponding PDG2012 values by 19%, 15% and 15%, respectively.
[ { "created": "Wed, 12 Jun 2013 06:10:47 GMT", "version": "v1" } ]
2015-06-16
[ [ "Wang", "Dong", "" ], [ "Ban", "Yong", "" ], [ "Li", "Gang", "" ] ]
The study on $\rho-\omega$ mixing is mainly focused on vector mesons decay with isospin I=1, namely $\rho(\omega)\to\pi^+\pi^-$ process. In this paper, we present the study of $\rho-\omega$ mixing in $\rho(\omega)\to\pi^+\pi^-\pi^0$ (I=0) using a flavor parameterization model for $J/\psi\to VP$ process. By fitting theoretical frame to PDG data, we obtain the SU(3)-breaking effect parameters $s_V=0.03\pm 0.12,\ s_P=0.17\pm 0.17$ and the $\rho-\omega$ mixing polarization operator $\Pi_{\rho \omega}=0.006\pm 0.011\text{\text{GeV}}^2$. The branching ratios are also renewed when mixing effect is incorporated: $Br(J/\psi\to \omega\pi^0) = (3.64 \pm 0.37)\times 10^{-4}$, $Br(J/\psi\to \omega\eta) = (1.48 \pm 0.17)\times 10^{-3}$, $Br(J/\psi\to \omega\eta^{\prime}) = (1.55\pm 0.56)\times 10^{-4}$; they are different from the corresponding PDG2012 values by 19%, 15% and 15%, respectively.
1905.10384
Philip Waite
Andrew Blance, Michael Spannowsky, Philip Waite
Adversarially-trained autoencoders for robust unsupervised new physics searches
19 pages, 7 figures. V2: Some discussions extended, agrees with version published in JHEP
J. High Energ. Phys. (2019) 2019: 47
10.1007/JHEP10(2019)047
IPPP/19/41
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Machine learning techniques in particle physics are most powerful when they are trained directly on data, to avoid sensitivity to theoretical uncertainties or an underlying bias on the expected signal. To be able to train on data in searches for new physics, anomaly detection methods are imperative, which can be realised by an autoencoder acting as an unsupervised classifier. The last source of uncertainties affecting the classifier are then experimental uncertainties in the reconstruction of the final-state objects. To mitigate their effect on the classifier and to allow for a realistic assessment of the method, we propose to combine the autoencoder with an adversarial neural network to remove its sensitivity to the smearing of the final-state objects. We quantify its effect and show that one can achieve a robust anomaly detection in resonance-induced $t\bar{t}$ final states.
[ { "created": "Fri, 24 May 2019 18:00:14 GMT", "version": "v1" }, { "created": "Fri, 18 Oct 2019 10:37:30 GMT", "version": "v2" } ]
2019-10-21
[ [ "Blance", "Andrew", "" ], [ "Spannowsky", "Michael", "" ], [ "Waite", "Philip", "" ] ]
Machine learning techniques in particle physics are most powerful when they are trained directly on data, to avoid sensitivity to theoretical uncertainties or an underlying bias on the expected signal. To be able to train on data in searches for new physics, anomaly detection methods are imperative, which can be realised by an autoencoder acting as an unsupervised classifier. The last source of uncertainties affecting the classifier are then experimental uncertainties in the reconstruction of the final-state objects. To mitigate their effect on the classifier and to allow for a realistic assessment of the method, we propose to combine the autoencoder with an adversarial neural network to remove its sensitivity to the smearing of the final-state objects. We quantify its effect and show that one can achieve a robust anomaly detection in resonance-induced $t\bar{t}$ final states.
1712.08199
Fredrick Olness
D. B. Clark, E. Godat, T. Jezo, C. Keppel, K. Kovarik, A. Kusina, F. Lyonnet, J.G. Morfin, F. I. Olness, J.F. Owens, I. Schienbein, J. Y. Yu
LHC data and its impact on nCTEQ15 PDFs
6 pages, 6 figures. 25th International Workshop on Deep-Inelastic Scattering and Related Topics (DIS 2017). PoS(DIS2017)204
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The LHC heavy ion data for W/Z production can provide new incisive information on the PDFs. This data is sensitive to the heavier quark flavors (strange and charm) in a high energy kinematic region; this can facilitate the determination of PDFs in the small x region where previous data was limited. At present, the flavor separation of the proton PDFs is dependent on DIS data from nuclear targets. Therefore, improved nuclear corrections can also yield enhanced flavor determination of both the proton and nuclear PDFs.
[ { "created": "Thu, 21 Dec 2017 20:27:48 GMT", "version": "v1" } ]
2017-12-25
[ [ "Clark", "D. B.", "" ], [ "Godat", "E.", "" ], [ "Jezo", "T.", "" ], [ "Keppel", "C.", "" ], [ "Kovarik", "K.", "" ], [ "Kusina", "A.", "" ], [ "Lyonnet", "F.", "" ], [ "Morfin", "J. G.", ""...
The LHC heavy ion data for W/Z production can provide new incisive information on the PDFs. This data is sensitive to the heavier quark flavors (strange and charm) in a high energy kinematic region; this can facilitate the determination of PDFs in the small x region where previous data was limited. At present, the flavor separation of the proton PDFs is dependent on DIS data from nuclear targets. Therefore, improved nuclear corrections can also yield enhanced flavor determination of both the proton and nuclear PDFs.
hep-ph/0203017
Manmohan Gupta
Harleen Dahiya and Manmohan Gupta
Octet magnetic moments and the violation of CGSR in $\chi$QM with configuration mixing
5 pages, 1 Table, RevTeX
null
null
null
hep-ph
null
Octet baryon magnetic moments are calculated within \chiQM, respecting color spin spin forces (Szczepaniak et al., PRL 87, 072001(2001)), incorporating the orbital angular momentum as well as the quark sea contribution through the Cheng and Li mechanism (PRL 80, 2789(1998)). Using configuration mixing generated by color spin spin forces as well as the concept of ``effective'' quark mass to include the effects of confinement, we are able to get an excellent fit to the octet magnetic moments as well as the violation of Coleman Glashow Sum Rule (CGSR) without any further input except for the ones already used in \chiQM as well as in NRQM. Specifically, in the case of p, \Sigma^+, \Xi^o, and violation of CGSR we get a perfect fit whereas in almost all the other cases the results are within 5% of the data.
[ { "created": "Sat, 2 Mar 2002 04:45:09 GMT", "version": "v1" } ]
2007-05-23
[ [ "Dahiya", "Harleen", "" ], [ "Gupta", "Manmohan", "" ] ]
Octet baryon magnetic moments are calculated within \chiQM, respecting color spin spin forces (Szczepaniak et al., PRL 87, 072001(2001)), incorporating the orbital angular momentum as well as the quark sea contribution through the Cheng and Li mechanism (PRL 80, 2789(1998)). Using configuration mixing generated by color spin spin forces as well as the concept of ``effective'' quark mass to include the effects of confinement, we are able to get an excellent fit to the octet magnetic moments as well as the violation of Coleman Glashow Sum Rule (CGSR) without any further input except for the ones already used in \chiQM as well as in NRQM. Specifically, in the case of p, \Sigma^+, \Xi^o, and violation of CGSR we get a perfect fit whereas in almost all the other cases the results are within 5% of the data.
hep-ph/0303155
J. T. Londergan
J.T. Londergan and A.W. Thomas
Charge Symmetry Violation Corrections to Determination of the Weinberg Angle in Neutrino Reactions
7 pages, no figures; expanded discussion of N.ne.Z corrections
Phys.Rev.D67:111901,2003
10.1103/PhysRevD.67.111901
null
hep-ph
null
We show that the correction to the Paschos-Wolfenstein relation associated with charge symmetry violation in the valence quark distributions is essentially model independent. It is proportional to a ratio of quark momenta that is independent of Q^2. This result provides a natural explanation of the surprisingly good agreement found between our earlier estimates within several different models. When applied to the recent NuTeV measurement, this effect significantly reduces the discrepancy with other determinations of the Weinberg angle.
[ { "created": "Tue, 18 Mar 2003 19:43:29 GMT", "version": "v1" }, { "created": "Fri, 30 May 2003 19:11:35 GMT", "version": "v2" } ]
2010-02-17
[ [ "Londergan", "J. T.", "" ], [ "Thomas", "A. W.", "" ] ]
We show that the correction to the Paschos-Wolfenstein relation associated with charge symmetry violation in the valence quark distributions is essentially model independent. It is proportional to a ratio of quark momenta that is independent of Q^2. This result provides a natural explanation of the surprisingly good agreement found between our earlier estimates within several different models. When applied to the recent NuTeV measurement, this effect significantly reduces the discrepancy with other determinations of the Weinberg angle.
hep-ph/0210379
Enrico Lunghi
E. Lunghi
Improved Model-Independent Analysis of Semileptonic and Radiative Rare Decays
7 pages, 6 figures, talk given at the 10th International Conference on Supersymmetry and Unification of Fundamental Interactions, June 17-23, 2002, DESY Hamburg
null
null
null
hep-ph
null
We study the impact of recent B-factories measurements and upper limit of radiative and semileptonic rare B-decays. We present model independent constraints on the relevant Wilson coefficients and show the impact on the parameter space of some concrete realizations of the Minimal Supersymmetric Standard Model.
[ { "created": "Mon, 28 Oct 2002 14:13:43 GMT", "version": "v1" } ]
2007-05-23
[ [ "Lunghi", "E.", "" ] ]
We study the impact of recent B-factories measurements and upper limit of radiative and semileptonic rare B-decays. We present model independent constraints on the relevant Wilson coefficients and show the impact on the parameter space of some concrete realizations of the Minimal Supersymmetric Standard Model.
hep-ph/9605403
Matthias Heyssler
Matthias Heyssler (Department of Physics, Durham)
A leptophobic massive vector boson at the Tevatron and the LHC
25 pages, LaTeX source code, 9 postscript figures, uses epsf.sty and epsfig.sty, encoded via 'uufiles'
Phys.Rev. D54 (1996) 5845-5854
10.1103/PhysRevD.54.5845
DTP/96/42
hep-ph
null
Recent measurements of the single inclusive jet cross section at the Tevatron by the CDF Collaboration maybe suggest a modified picture of QCD in the large $E_T$ range. One possible explanation of the measured jet excess is the introduction of a neutral heavy vector boson $Z'$. A parameter fit of this new model to the CDF data, in leading order perturbation theory, is performed, and the question of how the corresponding single inclusive jet cross sections and the dijet angular distributions at the LHC are affected by this additional $Z'$ is discussed. We conclude that the $Z'$ will play a pivotal role for typical LHC centre-of-mass energies, thus providing a direct test of this theory.
[ { "created": "Sun, 26 May 1996 18:29:37 GMT", "version": "v1" }, { "created": "Mon, 27 May 1996 15:25:22 GMT", "version": "v2" } ]
2009-10-28
[ [ "Heyssler", "Matthias", "", "Department of Physics, Durham" ] ]
Recent measurements of the single inclusive jet cross section at the Tevatron by the CDF Collaboration maybe suggest a modified picture of QCD in the large $E_T$ range. One possible explanation of the measured jet excess is the introduction of a neutral heavy vector boson $Z'$. A parameter fit of this new model to the CDF data, in leading order perturbation theory, is performed, and the question of how the corresponding single inclusive jet cross sections and the dijet angular distributions at the LHC are affected by this additional $Z'$ is discussed. We conclude that the $Z'$ will play a pivotal role for typical LHC centre-of-mass energies, thus providing a direct test of this theory.
hep-ph/9511379
K. J. Barnes
K.J.Barnes, O.J.Senior, N.D.Virgo
Reconstructed CKM Matrices
15 pages,LaTeX,no macros
J.Phys.A29:4957-4966,1996
10.1088/0305-4470/29/16/017
SHEP 95-33
hep-ph
null
We construct quark mixing matrices within a group theoretic framework which is easily applicable to any number of generations. Familiar cases are retrieved and related, and it is hoped that our viewpoint may have advantages both phenomenologically and for constructing underlying mass matrix schemes.
[ { "created": "Mon, 20 Nov 1995 17:03:48 GMT", "version": "v1" } ]
2019-08-17
[ [ "Barnes", "K. J.", "" ], [ "Senior", "O. J.", "" ], [ "Virgo", "N. D.", "" ] ]
We construct quark mixing matrices within a group theoretic framework which is easily applicable to any number of generations. Familiar cases are retrieved and related, and it is hoped that our viewpoint may have advantages both phenomenologically and for constructing underlying mass matrix schemes.
2004.04036
Vladimir Tello
Goran Senjanovic and Vladimir Tello
Strong CP violation: problem or blessing?
some clarifications made, references added, 9 pages, 1 figure
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We readdress the issue of strong CP violation both in the Standard Model and in the Minimal Left-Right Symmetric Model and try to clear the confusion that seems to still pervade the field. We argue that the smallness of strong CP violation, while harmless and basically decoupled from the rest of physics in the SM, in the context of LR symmetry provides a blessing by helping to narrow down the parameter space of the theory and connecting apparently uncorrelated physical quantities. In particular, in the context of left-right symmetry being parity, it either points to the suppression of leptonic CP violation noticed before, or it leads to relatively light right-handed neutrinos, potentially accessible at the next hadron collider. The latter, more natural in view of complex quark Yukawa couplings, goes hand in hand with the smallness of lepton flavor violation and enhances the possibility of observing neutrinoless double beta decay.
[ { "created": "Wed, 8 Apr 2020 15:05:02 GMT", "version": "v1" }, { "created": "Thu, 11 Jun 2020 19:11:42 GMT", "version": "v2" } ]
2020-06-15
[ [ "Senjanovic", "Goran", "" ], [ "Tello", "Vladimir", "" ] ]
We readdress the issue of strong CP violation both in the Standard Model and in the Minimal Left-Right Symmetric Model and try to clear the confusion that seems to still pervade the field. We argue that the smallness of strong CP violation, while harmless and basically decoupled from the rest of physics in the SM, in the context of LR symmetry provides a blessing by helping to narrow down the parameter space of the theory and connecting apparently uncorrelated physical quantities. In particular, in the context of left-right symmetry being parity, it either points to the suppression of leptonic CP violation noticed before, or it leads to relatively light right-handed neutrinos, potentially accessible at the next hadron collider. The latter, more natural in view of complex quark Yukawa couplings, goes hand in hand with the smallness of lepton flavor violation and enhances the possibility of observing neutrinoless double beta decay.
1307.4755
Stefano Di Chiara
Matti Antola, Stefano Di Chiara, Kimmo Tuominen
Ultraviolet Complete Technicolor and Higgs Physics at LHC
31 pages, 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We construct a Technicolor model which provides masses for the electroweak gauge bosons and for all the Standard Model matter fields. Starting from an ultraviolet complete supersymmetric technicolor, we propose a scenario where all elementary scalars, gauginos, and higgsinos are decoupled at an energy scale substantially higher than the electroweak scale, therefore avoiding the little hierarchy problem of the minimal supersymmetric standard model. The resulting low energy theory has an SU(3) global symmetry whose breaking to SO(3) leads to electroweak symmetry breaking. We study in detail the phenomenology of this theory and demonstrate that it reproduces the present LHC data at the same level of precision as the Standard Model itself.
[ { "created": "Wed, 17 Jul 2013 20:00:01 GMT", "version": "v1" } ]
2013-07-19
[ [ "Antola", "Matti", "" ], [ "Di Chiara", "Stefano", "" ], [ "Tuominen", "Kimmo", "" ] ]
We construct a Technicolor model which provides masses for the electroweak gauge bosons and for all the Standard Model matter fields. Starting from an ultraviolet complete supersymmetric technicolor, we propose a scenario where all elementary scalars, gauginos, and higgsinos are decoupled at an energy scale substantially higher than the electroweak scale, therefore avoiding the little hierarchy problem of the minimal supersymmetric standard model. The resulting low energy theory has an SU(3) global symmetry whose breaking to SO(3) leads to electroweak symmetry breaking. We study in detail the phenomenology of this theory and demonstrate that it reproduces the present LHC data at the same level of precision as the Standard Model itself.
1304.4631
Matin Mojaza
Stanley J. Brodsky, Matin Mojaza and Xing-Gang Wu
Systematic Scale-Setting to All Orders: The Principle of Maximum Conformality and Commensurate Scale Relations
20 pages; Appendix added. This version matches the published paper
Phys. Rev. D 89 (2014) 014027
10.1103/PhysRevD.89.014027
SLAC-PUB-15430, CP3-Origins-2013-9 DNRF90, DIAS-2013-9
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present in detail a new systematic method which can be used to automatically eliminate the renormalization scheme and scale ambiguities in perturbative QCD predictions at all orders. We show that all of the nonconformal \beta-dependent terms in a QCD perturbative series can be readily identified by generalizing the conventional renormalization schemes based on dimensional regularization. We then demonstrate that the nonconformal series of pQCD at any order can be resummed systematically into the scale of the QCD coupling in a unique and unambiguous way due to a special degeneracy of the \beta-terms in the series. The resummation follows from the principal of maximum conformality (PMC) and assigns a unique scale for the running coupling at each perturbative order. The final result is independent of the initial choices of renormalization scheme and scale, in accordance with the principles of the renormalization group, and thus eliminates an unnecessary source of systematic error in physical predictions. We exhibit several examples known to order \alpha_s^4; i.e. i) the electron-positron annihilation into hadrons, ii) the tau-lepton decay to hadrons, iii) the Bjorken and Gross-Llewellyn Smith (GLS) sum rules, and iv) the static quark potential. We show that the final series of the first three cases are all given in terms of the anomalous dimension of the gluon field, in accordance with conformality, and with all non-conformal properties encoded in the running coupling. The final expressions for the Bjorken and GLS sum rules directly lead to the generalized Crewther relations, exposing another relevant feature of conformality. The static quark potential shows that PMC scale setting in the Abelian limit is to all orders consistent with QED scale setting. Finally, we demonstrate that the method applies to any renormalization scheme and [...]
[ { "created": "Tue, 16 Apr 2013 22:05:29 GMT", "version": "v1" }, { "created": "Sun, 28 Apr 2013 06:32:02 GMT", "version": "v2" }, { "created": "Sun, 19 Jan 2014 23:53:49 GMT", "version": "v3" } ]
2014-04-11
[ [ "Brodsky", "Stanley J.", "" ], [ "Mojaza", "Matin", "" ], [ "Wu", "Xing-Gang", "" ] ]
We present in detail a new systematic method which can be used to automatically eliminate the renormalization scheme and scale ambiguities in perturbative QCD predictions at all orders. We show that all of the nonconformal \beta-dependent terms in a QCD perturbative series can be readily identified by generalizing the conventional renormalization schemes based on dimensional regularization. We then demonstrate that the nonconformal series of pQCD at any order can be resummed systematically into the scale of the QCD coupling in a unique and unambiguous way due to a special degeneracy of the \beta-terms in the series. The resummation follows from the principal of maximum conformality (PMC) and assigns a unique scale for the running coupling at each perturbative order. The final result is independent of the initial choices of renormalization scheme and scale, in accordance with the principles of the renormalization group, and thus eliminates an unnecessary source of systematic error in physical predictions. We exhibit several examples known to order \alpha_s^4; i.e. i) the electron-positron annihilation into hadrons, ii) the tau-lepton decay to hadrons, iii) the Bjorken and Gross-Llewellyn Smith (GLS) sum rules, and iv) the static quark potential. We show that the final series of the first three cases are all given in terms of the anomalous dimension of the gluon field, in accordance with conformality, and with all non-conformal properties encoded in the running coupling. The final expressions for the Bjorken and GLS sum rules directly lead to the generalized Crewther relations, exposing another relevant feature of conformality. The static quark potential shows that PMC scale setting in the Abelian limit is to all orders consistent with QED scale setting. Finally, we demonstrate that the method applies to any renormalization scheme and [...]
1506.04517
Andreas Vogt
S. Moch (Hamburg U., Inst. Theor. Phys. II), J.A.M. Vermaseren (NIKHEF, Amsterdam), A. Vogt (Liverpool U., Dept. Math.)
On gamma_5 in higher-order QCD calculations and the NNLO evolution of the polarized valence distribution
11 pages, Latex, 2 figures. FORM and Fortran files of the main results available with the source
null
null
DESY 15-061, NIKHEF 15-018, LTH 1042
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We discuss the prescription for the Dirac matrix gamma_5 in dimensional regularization used in most second- and third-order QCD calculations of collider cross sections. We provide an alternative implementation of this approach that avoids the use of an explicit form of gamma_5 and of its (anti-) commutation relations in the most important case of no more than one gamma_5 in each fermion trace. This treatment is checked by computing the third-order corrections to the structure functions F_2 and g_1 in charged-current deep-inelastic scattering with axial-vector couplings to the W-bosons. We derive the so far unknown third-order helicity-difference splitting function Delta P_ns^(2)s that contributes to the next-to-next-to-leading order (NNLO) evolution of the polarized valence quark distribution of the nucleon. This function is negligible at momentum fractions x >~ 0.3 but relevant at x << 1.
[ { "created": "Mon, 15 Jun 2015 08:47:47 GMT", "version": "v1" } ]
2015-06-16
[ [ "Moch", "S.", "", "Hamburg U., Inst. Theor. Phys. II" ], [ "Vermaseren", "J. A. M.", "", "NIKHEF, Amsterdam" ], [ "Vogt", "A.", "", "Liverpool U., Dept. Math." ] ]
We discuss the prescription for the Dirac matrix gamma_5 in dimensional regularization used in most second- and third-order QCD calculations of collider cross sections. We provide an alternative implementation of this approach that avoids the use of an explicit form of gamma_5 and of its (anti-) commutation relations in the most important case of no more than one gamma_5 in each fermion trace. This treatment is checked by computing the third-order corrections to the structure functions F_2 and g_1 in charged-current deep-inelastic scattering with axial-vector couplings to the W-bosons. We derive the so far unknown third-order helicity-difference splitting function Delta P_ns^(2)s that contributes to the next-to-next-to-leading order (NNLO) evolution of the polarized valence quark distribution of the nucleon. This function is negligible at momentum fractions x >~ 0.3 but relevant at x << 1.
1504.05893
Sergey Troshin
S.M. Troshin, N.E. Tyurin
Implications of the LHC results for the cosmic data interpretations
7 pages, 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Absence of the signals of the physics beyond the Standard Model at the available LHC energies means that the several of cosmic data peculiarities could be associated with an emergency of the new scattering mode. This reflective scattering mode can be used for explanations of the measurements performed under the study of extensive air showers (EAS).
[ { "created": "Wed, 22 Apr 2015 17:31:40 GMT", "version": "v1" } ]
2015-04-23
[ [ "Troshin", "S. M.", "" ], [ "Tyurin", "N. E.", "" ] ]
Absence of the signals of the physics beyond the Standard Model at the available LHC energies means that the several of cosmic data peculiarities could be associated with an emergency of the new scattering mode. This reflective scattering mode can be used for explanations of the measurements performed under the study of extensive air showers (EAS).
2010.14748
Martin Hentschinski
Martin Hentschinski
Lipatov's QCD high energy effective action: past and future
25 pages, 39 figures; a chapter for the memorial volume "From the past to the future - the legacy of Lev Lipatov"
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this contribution we briefly review some aspects of Lipatov's gauge invariant QCD high energy effective action. The high energy effective provides a field theory framework to systematically factorize QCD scattering amplitudes and related theories in the limit of high center of mass energies. After a short review of the underlying concepts, we address the question how the high energy effective action can be used for actual calculations. As an explicit example we review the derivation of the gluon Regge trajectory up to 2 loop. We then review two topics of current interest: automatic amplitude generation of high energy effective action amplitudes and a discussion of the relation between the so-called Color-Glass-Condensate framework and the high energy effective action.
[ { "created": "Wed, 28 Oct 2020 04:53:41 GMT", "version": "v1" } ]
2020-10-29
[ [ "Hentschinski", "Martin", "" ] ]
In this contribution we briefly review some aspects of Lipatov's gauge invariant QCD high energy effective action. The high energy effective provides a field theory framework to systematically factorize QCD scattering amplitudes and related theories in the limit of high center of mass energies. After a short review of the underlying concepts, we address the question how the high energy effective action can be used for actual calculations. As an explicit example we review the derivation of the gluon Regge trajectory up to 2 loop. We then review two topics of current interest: automatic amplitude generation of high energy effective action amplitudes and a discussion of the relation between the so-called Color-Glass-Condensate framework and the high energy effective action.
1102.0917
Flavia Dias
Flavia A. Dias, Emily Nurse, Gavin Hesketh
LO vs NLO comparisons for Z + jets: MC as a tool for background determination for NP searches at LHC
20 pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The leptonic decays of the heavy gauge bosons W and/or Z provide a clear experimental signature at hadron colliders. The production of accompanying jets is an excellent signal to probe QCD, while also being the main background to many searches for new physics. Describing the complex final state of W or Z + jets is a theoretical challenge with most existing calculations combining matrix elements for high energy jet production with a parton shower for lower energy jet production. We focus on two models: SHERPA, which uses Leading Order matrix elements for boson and jet production; and POWHEG with HERWIG++, which uses a Next-To-Leading Order Matrix element for Z production. In order to isolate the impact of the matrix elements for jet production, it is first essential to constrain the differences in the rest of the calculation in each case: specifically, the Multiple Parton Interaction models, and the tuning of the parton shower interfaced to the matrix elements. We test all three aspects of these models against data from the Tevatron, and perform a study of some basic kinematic variables at the LHC energy.
[ { "created": "Fri, 4 Feb 2011 14:01:31 GMT", "version": "v1" } ]
2015-03-18
[ [ "Dias", "Flavia A.", "" ], [ "Nurse", "Emily", "" ], [ "Hesketh", "Gavin", "" ] ]
The leptonic decays of the heavy gauge bosons W and/or Z provide a clear experimental signature at hadron colliders. The production of accompanying jets is an excellent signal to probe QCD, while also being the main background to many searches for new physics. Describing the complex final state of W or Z + jets is a theoretical challenge with most existing calculations combining matrix elements for high energy jet production with a parton shower for lower energy jet production. We focus on two models: SHERPA, which uses Leading Order matrix elements for boson and jet production; and POWHEG with HERWIG++, which uses a Next-To-Leading Order Matrix element for Z production. In order to isolate the impact of the matrix elements for jet production, it is first essential to constrain the differences in the rest of the calculation in each case: specifically, the Multiple Parton Interaction models, and the tuning of the parton shower interfaced to the matrix elements. We test all three aspects of these models against data from the Tevatron, and perform a study of some basic kinematic variables at the LHC energy.
1510.02180
Claude Bernard
C. Bernard
Effective Field Theories and Lattice QCD
Talk given at the 8th International Workshop on Chiral Dynamics, June 29--July 3, 2015, Pisa, Italy. 23 pages, 14 figures
null
null
null
hep-ph hep-lat
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I describe some of the many connections between lattice QCD and effective field theories, focusing in particular on chiral effective theory, and, to a lesser extent, Symanzik effective theory. I first discuss the ways in which effective theories have enabled and supported lattice QCD calculations. Particular attention is paid to the inclusion of discretization errors, for a variety of lattice QCD actions, into chiral effective theory. Several other examples of the usefulness of chiral perturbation theory, including the encoding of partial quenching and of twisted boundary conditions, are also described. In the second part of the talk, I turn to results from lattice QCD for the low energy constants of the two- and three-flavor chiral theories. I concentrate here on mesonic quantities, but the dependence of the nucleon mass on the pion mass is also discussed. Finally I describe some recent preliminary lattice QCD calculations by the MILC Collaboration relating to the three-flavor chiral limit.
[ { "created": "Thu, 8 Oct 2015 02:02:44 GMT", "version": "v1" } ]
2015-10-09
[ [ "Bernard", "C.", "" ] ]
I describe some of the many connections between lattice QCD and effective field theories, focusing in particular on chiral effective theory, and, to a lesser extent, Symanzik effective theory. I first discuss the ways in which effective theories have enabled and supported lattice QCD calculations. Particular attention is paid to the inclusion of discretization errors, for a variety of lattice QCD actions, into chiral effective theory. Several other examples of the usefulness of chiral perturbation theory, including the encoding of partial quenching and of twisted boundary conditions, are also described. In the second part of the talk, I turn to results from lattice QCD for the low energy constants of the two- and three-flavor chiral theories. I concentrate here on mesonic quantities, but the dependence of the nucleon mass on the pion mass is also discussed. Finally I describe some recent preliminary lattice QCD calculations by the MILC Collaboration relating to the three-flavor chiral limit.
2101.04525
Bob Stienen
The DarkMachines High Dimensional Sampling Group: Csaba Bal\'azs, Melissa van Beekveld, Sascha Caron, Barry M. Dillon, Ben Farmer, Andrew Fowlie, Eduardo C. Garrido-Merch\'an, Will Handley, Luc Hendriks, Gu{\dh}laugur J\'ohannesson, Adam Leinweber, Judita Mamu\v{z}i\'c, Gregory D. Martinez, Sydney Otten, Pat Scott, Roberto Ruiz de Austri, Zachary Searle, Bob Stienen, Joaquin Vanschoren, Martin White
A comparison of optimisation algorithms for high-dimensional particle and astrophysics applications
Experimental framework publicly available at http://www.github.com/darkmachines/high-dimensional-sampling
null
10.1007/JHEP05(2021)108
null
hep-ph physics.comp-ph
http://creativecommons.org/licenses/by/4.0/
Optimisation problems are ubiquitous in particle and astrophysics, and involve locating the optimum of a complicated function of many parameters that may be computationally expensive to evaluate. We describe a number of global optimisation algorithms that are not yet widely used in particle astrophysics, benchmark them against random sampling and existing techniques, and perform a detailed comparison of their performance on a range of test functions. These include four analytic test functions of varying dimensionality, and a realistic example derived from a recent global fit of weak-scale supersymmetry. Although the best algorithm to use depends on the function being investigated, we are able to present general conclusions about the relative merits of random sampling, Differential Evolution, Particle Swarm Optimisation, the Covariance Matrix Adaptation Evolution Strategy, Bayesian Optimisation, Grey Wolf Optimisation, and the PyGMO Artificial Bee Colony, Gaussian Particle Filter and Adaptive Memory Programming for Global Optimisation algorithms.
[ { "created": "Tue, 12 Jan 2021 14:48:58 GMT", "version": "v1" }, { "created": "Thu, 1 Apr 2021 09:06:11 GMT", "version": "v2" } ]
2021-11-03
[ [ "The DarkMachines High Dimensional Sampling Group", "", "" ], [ "Balázs", "Csaba", "" ], [ "van Beekveld", "Melissa", "" ], [ "Caron", "Sascha", "" ], [ "Dillon", "Barry M.", "" ], [ "Farmer", "Ben", "" ], [ "Fowli...
Optimisation problems are ubiquitous in particle and astrophysics, and involve locating the optimum of a complicated function of many parameters that may be computationally expensive to evaluate. We describe a number of global optimisation algorithms that are not yet widely used in particle astrophysics, benchmark them against random sampling and existing techniques, and perform a detailed comparison of their performance on a range of test functions. These include four analytic test functions of varying dimensionality, and a realistic example derived from a recent global fit of weak-scale supersymmetry. Although the best algorithm to use depends on the function being investigated, we are able to present general conclusions about the relative merits of random sampling, Differential Evolution, Particle Swarm Optimisation, the Covariance Matrix Adaptation Evolution Strategy, Bayesian Optimisation, Grey Wolf Optimisation, and the PyGMO Artificial Bee Colony, Gaussian Particle Filter and Adaptive Memory Programming for Global Optimisation algorithms.
2209.13475
Jiaxing Zhao
Jiaxing Zhao and Pengfei Zhuang
$B_c$ enhancement with non-thermalized bottom quarks in nuclear collisions at Large Hadron Collider
6 pages, 4 figures
null
null
null
hep-ph nucl-th
http://creativecommons.org/publicdomain/zero/1.0/
We study $B_c$ production in high-energy nuclear collisions in a transport approach with dissociation and regeneration at finite temperatures. Due to the rare production in p+p collisions and the strong combination of uncorrelated $c$ and $\bar b$ quarks in the quark-gluon plasma, the $B_c$ yield is clearly enhanced in the nuclear collisions at the Large Hadron Collider. Besides, the centrality and momentum-dependent yield of $B_c$ sensitively reflect the thermalization degree of bottom quarks. And the newly observed experimental data favors a far from the thermal bottom quark distribution in the quark-gluon plasma.
[ { "created": "Tue, 27 Sep 2022 15:50:21 GMT", "version": "v1" } ]
2022-09-28
[ [ "Zhao", "Jiaxing", "" ], [ "Zhuang", "Pengfei", "" ] ]
We study $B_c$ production in high-energy nuclear collisions in a transport approach with dissociation and regeneration at finite temperatures. Due to the rare production in p+p collisions and the strong combination of uncorrelated $c$ and $\bar b$ quarks in the quark-gluon plasma, the $B_c$ yield is clearly enhanced in the nuclear collisions at the Large Hadron Collider. Besides, the centrality and momentum-dependent yield of $B_c$ sensitively reflect the thermalization degree of bottom quarks. And the newly observed experimental data favors a far from the thermal bottom quark distribution in the quark-gluon plasma.
2112.11465
Jan Sch\"utte-Engel
Asher Berlin, Diego Blas, Raffaele Tito D'Agnolo, Sebastian A. R. Ellis, Roni Harnik, Yonatan Kahn, Jan Sch\"utte-Engel
Detecting High-Frequency Gravitational Waves with Microwave Cavities
20 pages + appendix, 7 figures, matches journal version
null
10.1103/PhysRevD.105.116011
null
hep-ph astro-ph.HE astro-ph.IM hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We give a detailed treatment of electromagnetic signals generated by gravitational waves (GWs) in resonant cavity experiments. Our investigation corrects and builds upon previous studies by carefully accounting for the gauge dependence of relevant quantities. We work in a preferred frame for the laboratory, the proper detector frame, and show how to resum short-wavelength effects to provide analytic results that are exact for GWs of arbitrary wavelength. This formalism allows us to firmly establish that, contrary to previous claims, cavity experiments designed for the detection of axion dark matter only need to reanalyze existing data to search for high-frequency GWs with strains as small as $h\sim 10^{-22}-10^{-21}$. We also argue that directional detection is possible in principle using readout of multiple cavity modes. Further improvements in sensitivity are expected with cutting-edge advances in superconducting cavity technology.
[ { "created": "Tue, 21 Dec 2021 19:00:01 GMT", "version": "v1" }, { "created": "Mon, 24 Apr 2023 17:39:07 GMT", "version": "v2" } ]
2023-04-25
[ [ "Berlin", "Asher", "" ], [ "Blas", "Diego", "" ], [ "D'Agnolo", "Raffaele Tito", "" ], [ "Ellis", "Sebastian A. R.", "" ], [ "Harnik", "Roni", "" ], [ "Kahn", "Yonatan", "" ], [ "Schütte-Engel", "Jan", "" ...
We give a detailed treatment of electromagnetic signals generated by gravitational waves (GWs) in resonant cavity experiments. Our investigation corrects and builds upon previous studies by carefully accounting for the gauge dependence of relevant quantities. We work in a preferred frame for the laboratory, the proper detector frame, and show how to resum short-wavelength effects to provide analytic results that are exact for GWs of arbitrary wavelength. This formalism allows us to firmly establish that, contrary to previous claims, cavity experiments designed for the detection of axion dark matter only need to reanalyze existing data to search for high-frequency GWs with strains as small as $h\sim 10^{-22}-10^{-21}$. We also argue that directional detection is possible in principle using readout of multiple cavity modes. Further improvements in sensitivity are expected with cutting-edge advances in superconducting cavity technology.
hep-ph/9510332
C. S. Kim
C.S. Kim (KEK, Japan and Yonsei Univ, Korea) and J.H. Lin
Axial Anomaly and the Nucleon Spin
(1) A few changes and corrections made following Referee. (2) The difference between quark content of the proton (\Delta\Sigma_p) and that of the neutron (\Delta\Sigma_n) is evaluated. Neglecting the higher-order isospin corrections, this formula can reduce to Efremov's results in the large N_c limit
Mod.Phys.Lett. A11 (1996) 931-938
10.1142/S0217732396000941
null
hep-ph hep-lat nucl-th
null
In this letter, we have taken a particular Lagrangian, which was introduced to resolve U(1) problem, as an effective QCD Lagrangian, and have derived a formula of the quark content of the nucleon spin. The difference between quark content of the proton (\Delta\Sigma_p) and that of the neutron (\Delta\Sigma_n) is evaluated by this formula. Neglecting the higher-order isospin corrections, this formula can reduce to Efremov's results in the large N_c limit.
[ { "created": "Wed, 18 Oct 1995 03:02:43 GMT", "version": "v1" }, { "created": "Sat, 20 Jul 1996 08:12:56 GMT", "version": "v2" } ]
2009-10-28
[ [ "Kim", "C. S.", "", "KEK, Japan and Yonsei Univ, Korea" ], [ "Lin", "J. H.", "" ] ]
In this letter, we have taken a particular Lagrangian, which was introduced to resolve U(1) problem, as an effective QCD Lagrangian, and have derived a formula of the quark content of the nucleon spin. The difference between quark content of the proton (\Delta\Sigma_p) and that of the neutron (\Delta\Sigma_n) is evaluated by this formula. Neglecting the higher-order isospin corrections, this formula can reduce to Efremov's results in the large N_c limit.
hep-ph/0009261
Enrico Meggiolaro
Enrico Meggiolaro
Eikonal propagators and high-energy parton-parton scattering in gauge theories
36 pages, LaTeX file, + 1 PS figure
Nucl.Phys. B602 (2001) 261-288
10.1016/S0550-3213(01)00115-8
IFUP-TH/2000-27
hep-ph
null
In this paper we consider soft high-energy parton-parton scattering processes in gauge theories, i.e., elastic scattering processes involving partons at very high squared energies in the center of mass and small squared transferred momentum. By a direct resummation of perturbation theory in the limit we are considering, we derive expressions for the truncated-connected quark (antiquark) propagator in an external gluon field, as well as for the residue at the pole of the full unrenormalized propagator, both for scalar and fermion gauge theories. These are the basic ingredients to derive high-energy parton-parton scattering amplitudes, using the LSZ reduction formulae and a functional integral approach. The above procedure is also extended to include the case in which at least one of the partons is a gluon. The meaning and the validity of the results are discussed.
[ { "created": "Thu, 21 Sep 2000 22:57:53 GMT", "version": "v1" } ]
2009-10-31
[ [ "Meggiolaro", "Enrico", "" ] ]
In this paper we consider soft high-energy parton-parton scattering processes in gauge theories, i.e., elastic scattering processes involving partons at very high squared energies in the center of mass and small squared transferred momentum. By a direct resummation of perturbation theory in the limit we are considering, we derive expressions for the truncated-connected quark (antiquark) propagator in an external gluon field, as well as for the residue at the pole of the full unrenormalized propagator, both for scalar and fermion gauge theories. These are the basic ingredients to derive high-energy parton-parton scattering amplitudes, using the LSZ reduction formulae and a functional integral approach. The above procedure is also extended to include the case in which at least one of the partons is a gluon. The meaning and the validity of the results are discussed.
2306.12721
Victor Goncalves
Victor P. Goncalves, Michael Klasen, Bruno D. Moreira
Exclusive $J/\Psi$ plus jet associated production in ultraperipheral $PbPb$ collisions
9 pages, 4 figures, 2 tables
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of exclusive processes in ultraperipheral collisions at the Large Hadron Collider (LHC) has allowed us to test several aspects of the Standard Model and to search for New Physics. In this letter, we investigate the possibility of using these processes to improve our understanding of the quarkonium production mechanism through the study of the exclusive $J/\Psi$ plus jet associate production in ultraperipheral $PbPb$ collisions. We estimate the transverse - momentum and rapidity distributions considering that the $\gamma \gamma \rightarrow J/\Psi + X$ ($X = \gamma, \, g$) subprocess is described by the Non - Relativistic QCD (NRQCD) formalism and present predictions for the rapidity ranges covered by central and forward detectors. The experimental separation of these events is discussed and the results indicate that a future experimental analysis is, in principle, feasible in future runs of the LHC and the Future Circular Collider (FCC).
[ { "created": "Thu, 22 Jun 2023 07:53:26 GMT", "version": "v1" } ]
2023-06-23
[ [ "Goncalves", "Victor P.", "" ], [ "Klasen", "Michael", "" ], [ "Moreira", "Bruno D.", "" ] ]
The study of exclusive processes in ultraperipheral collisions at the Large Hadron Collider (LHC) has allowed us to test several aspects of the Standard Model and to search for New Physics. In this letter, we investigate the possibility of using these processes to improve our understanding of the quarkonium production mechanism through the study of the exclusive $J/\Psi$ plus jet associate production in ultraperipheral $PbPb$ collisions. We estimate the transverse - momentum and rapidity distributions considering that the $\gamma \gamma \rightarrow J/\Psi + X$ ($X = \gamma, \, g$) subprocess is described by the Non - Relativistic QCD (NRQCD) formalism and present predictions for the rapidity ranges covered by central and forward detectors. The experimental separation of these events is discussed and the results indicate that a future experimental analysis is, in principle, feasible in future runs of the LHC and the Future Circular Collider (FCC).
hep-ph/0004092
Gorbunov
D.S.Gorbunov and V.A.Ilyin
Stoponium Search at Photon Linear Collider
11 pages, 2 figures added, corrections taken into account result in increasing of signal significance
JHEP 0011:011,2000
10.1088/1126-6708/2000/11/011
null
hep-ph
null
In some supersymmetric extensions of the Standard Model fairly light superpartner of t-quark is predicted, which may form bound states ({\it stoponiums}) under certain conditions. We study prospects of search for stoponium at the future Photon Linear Collider. It is found that this machine could be the best machine for discovery and study of these resonances at some scenarios of supersymmetric extension of the Standard Model. In particular, if the $hh$ decay channel is dominant stoponium could be observed at the beginning of PLC run with collision energy tuned at the stoponium mass. If this channel is kinematically closed stoponium could be discovered in $gg$, $\gamma\gamma$ and $ZZ$ decay channels but higher statistics are needed. Effects of the stoponium-Higgs mixing and degeneracy are briefly discussed.
[ { "created": "Mon, 10 Apr 2000 16:40:25 GMT", "version": "v1" }, { "created": "Wed, 13 Dec 2000 18:22:35 GMT", "version": "v2" } ]
2011-05-18
[ [ "Gorbunov", "D. S.", "" ], [ "Ilyin", "V. A.", "" ] ]
In some supersymmetric extensions of the Standard Model fairly light superpartner of t-quark is predicted, which may form bound states ({\it stoponiums}) under certain conditions. We study prospects of search for stoponium at the future Photon Linear Collider. It is found that this machine could be the best machine for discovery and study of these resonances at some scenarios of supersymmetric extension of the Standard Model. In particular, if the $hh$ decay channel is dominant stoponium could be observed at the beginning of PLC run with collision energy tuned at the stoponium mass. If this channel is kinematically closed stoponium could be discovered in $gg$, $\gamma\gamma$ and $ZZ$ decay channels but higher statistics are needed. Effects of the stoponium-Higgs mixing and degeneracy are briefly discussed.
hep-ph/0308014
Karol Kolodziej
Karol Kolodziej (Univ. of Silesia), Fred Jegerlehner (DESY Zeuthen)
ee4fgamma, A program for e+e- -> 4f, 4fgamma with nonzero fermion masses
20 pages; version published in Computer Physics Communications
Comput.Phys.Commun.159:106-120,2004
10.1016/j.cpc.2004.03.001
DESY-03-099, SFB/CPP-03-16
hep-ph
null
A computer program ee4fgamma for calculating cross sections of any four fermion final state of e+e--annihilation at high energy and the corresponding bremsstrahlung reaction that is possible in the framework of the Standard Model is presented. As the fermion masses are arbitrary, the cross sections can be computed without any collinear cut, the on-shell top quark production can be studied and the Higgs boson exchange can be incorporated in a consistent way. The program can be used as a Monte Carlo generator of unweighted events as well.
[ { "created": "Fri, 1 Aug 2003 15:12:56 GMT", "version": "v1" }, { "created": "Wed, 21 Apr 2004 16:06:04 GMT", "version": "v2" } ]
2008-12-18
[ [ "Kolodziej", "Karol", "", "Univ. of Silesia" ], [ "Jegerlehner", "Fred", "", "DESY Zeuthen" ] ]
A computer program ee4fgamma for calculating cross sections of any four fermion final state of e+e--annihilation at high energy and the corresponding bremsstrahlung reaction that is possible in the framework of the Standard Model is presented. As the fermion masses are arbitrary, the cross sections can be computed without any collinear cut, the on-shell top quark production can be studied and the Higgs boson exchange can be incorporated in a consistent way. The program can be used as a Monte Carlo generator of unweighted events as well.
1011.0416
Michael Strickland
Michael Strickland, Jens O. Andersen, Lars E. Leganger, and Nan Su
Hard-thermal-loop QCD Thermodynamics
8 pages, 2 figures; Talk given at the Symposium on "High Energy Strong Interactions", Aug. 9-13, 2010, Yukawa Institute for Theoretical Physics, Kyoto, Japan; submitted to Prog. Theor. Phys. Suppl
Prog.Theor.Phys.Suppl.187:106-114,2011
10.1143/PTPS.187.106
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Naively resummed perturbative approximations to the thermodynamic functions of QCD do not converge at phenomenologically relevant temperatures. Here we review recent results of a three-loop hard-thermal-loop perturbation theory calculation of the thermodynamic functions of a quark-gluon plasma for general N_c and N_f. We show comparisons of our recent results with lattice data from both the hotQCD and Wuppertal-Budapest groups. We demonstrate that the three-loop hard-thermal-loop perturbation result for QCD thermodynamics agrees with lattice data down to temperatures T ~ 2 T_c.
[ { "created": "Mon, 1 Nov 2010 19:16:49 GMT", "version": "v1" } ]
2011-05-27
[ [ "Strickland", "Michael", "" ], [ "Andersen", "Jens O.", "" ], [ "Leganger", "Lars E.", "" ], [ "Su", "Nan", "" ] ]
Naively resummed perturbative approximations to the thermodynamic functions of QCD do not converge at phenomenologically relevant temperatures. Here we review recent results of a three-loop hard-thermal-loop perturbation theory calculation of the thermodynamic functions of a quark-gluon plasma for general N_c and N_f. We show comparisons of our recent results with lattice data from both the hotQCD and Wuppertal-Budapest groups. We demonstrate that the three-loop hard-thermal-loop perturbation result for QCD thermodynamics agrees with lattice data down to temperatures T ~ 2 T_c.
2212.08086
Peter Arnold
Peter Arnold, Omar Elgedawy, Shahin Iqbal
Are gluon showers inside a quark-gluon plasma strongly coupled? a theorist's test
6 pages, 3 figures. Main change for v3: minor clarifications added
null
null
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study whether in-medium showers of high-energy gluons can be treated as a sequence of individual splitting processes $g{\to}gg$, or whether there is significant quantum overlap between where one splitting ends and the next begins. Accounting for the Landau-Pomeranchuk-Migdal (LPM) effect, we calculate such overlap effects to leading order in high-energy $\alpha_{\rm s}(\mu)$ for the simplest theoretical situation. We investigate a measure of overlap effects that is independent of physics that can be absorbed into an effective value $\hat q_{\rm eff}$ of the jet-quenching parameter $\hat q$.
[ { "created": "Thu, 15 Dec 2022 19:00:03 GMT", "version": "v1" }, { "created": "Thu, 23 Feb 2023 23:19:10 GMT", "version": "v2" }, { "created": "Thu, 27 Jul 2023 19:41:36 GMT", "version": "v3" } ]
2023-07-31
[ [ "Arnold", "Peter", "" ], [ "Elgedawy", "Omar", "" ], [ "Iqbal", "Shahin", "" ] ]
We study whether in-medium showers of high-energy gluons can be treated as a sequence of individual splitting processes $g{\to}gg$, or whether there is significant quantum overlap between where one splitting ends and the next begins. Accounting for the Landau-Pomeranchuk-Migdal (LPM) effect, we calculate such overlap effects to leading order in high-energy $\alpha_{\rm s}(\mu)$ for the simplest theoretical situation. We investigate a measure of overlap effects that is independent of physics that can be absorbed into an effective value $\hat q_{\rm eff}$ of the jet-quenching parameter $\hat q$.
hep-ph/9504377
Sergei Kulagin
S.A.Kulagin, W.Melnitchouk, G.Piller and W.Weise
SPIN-DEPENDENT NUCLEAR STRUCTURE FUNCTIONS: GENERAL APPROACH WITH APPLICATION TO THE DEUTERON
26 pages RevTeX, 9 figures available upon request
Phys.Rev.C52:932-946,1995
10.1103/PhysRevC.52.932
TPR--94--34; ADP--94--22/T162
hep-ph nucl-th
null
We study deep-inelastic scattering from polarized nuclei within a covariant framework. A clear connection is established between relativistic and non-relativistic limits, which enables a rigorous derivation of convolution formulae for the spin-dependent nuclear structure functions g_1^A and g_2^A in terms of off-mass-shell extrapolations of polarized nucleon structure functions, g_1^N and g_2^N. Approximate expressions for g_{1,2}^A are obtained by expanding the off-shell g_{1,2}^N about their on-shell limits. As an application of the formalism we consider nuclear effects in the deuteron, knowledge of which is necessary to obtain accurate information on the spin-dependent structure functions of the neutron.
[ { "created": "Mon, 24 Apr 1995 14:56:21 GMT", "version": "v1" } ]
2009-09-25
[ [ "Kulagin", "S. A.", "" ], [ "Melnitchouk", "W.", "" ], [ "Piller", "G.", "" ], [ "Weise", "W.", "" ] ]
We study deep-inelastic scattering from polarized nuclei within a covariant framework. A clear connection is established between relativistic and non-relativistic limits, which enables a rigorous derivation of convolution formulae for the spin-dependent nuclear structure functions g_1^A and g_2^A in terms of off-mass-shell extrapolations of polarized nucleon structure functions, g_1^N and g_2^N. Approximate expressions for g_{1,2}^A are obtained by expanding the off-shell g_{1,2}^N about their on-shell limits. As an application of the formalism we consider nuclear effects in the deuteron, knowledge of which is necessary to obtain accurate information on the spin-dependent structure functions of the neutron.
hep-ph/0405167
Rohini Godbole Professor
Thomas Gajdosik, Rohini M. Godbole and Sabine Kraml
Fermion polarization in sfermion decays as a probe of CP phases in the MSSM
19 pages,8 figures, LaTeX, References added Vesion to appear in JHEP. A discussion on two loop contribution to the dipole moments added. Rest of the discussion and conclusions are unaltered. Revised acknowledgement section
JHEP0409:051,2004
10.1088/1126-6708/2004/09/051
CERN-PH-TH/2004-086
hep-ph
null
The longitudinal polarization of fermions (tops and taus) produced in sfermion decays to neutralinos or charginos can be a useful tool for the determination of SUSY parameters. We discuss this fermion polarization in the context of the MSSM with complex parameters. We show that the dependence on CP-violating phases can be large and that the fermion polarization may hence be used as a sensitive probe of CP phases in the MSSM.
[ { "created": "Tue, 18 May 2004 13:13:07 GMT", "version": "v1" }, { "created": "Thu, 27 May 2004 11:30:02 GMT", "version": "v2" }, { "created": "Mon, 27 Sep 2004 13:30:21 GMT", "version": "v3" } ]
2008-11-26
[ [ "Gajdosik", "Thomas", "" ], [ "Godbole", "Rohini M.", "" ], [ "Kraml", "Sabine", "" ] ]
The longitudinal polarization of fermions (tops and taus) produced in sfermion decays to neutralinos or charginos can be a useful tool for the determination of SUSY parameters. We discuss this fermion polarization in the context of the MSSM with complex parameters. We show that the dependence on CP-violating phases can be large and that the fermion polarization may hence be used as a sensitive probe of CP phases in the MSSM.
hep-ph/9907258
Chung-I. Tan
R. C. Brower, J. McGreevy, and C-I Tan
Stringy Model for QCD at Finite Density and Generalized Hagedorn Temperature
12 pages, Latex, 2 eps-files, uses sprocl.sty
null
null
Brown-HET-1188
hep-ph hep-lat hep-th
null
Using generic properties of string theories, we show how interesting non-perturbative features of QCD can be exploited in heavy ion collisions. In particular, a generalized "semi-circle" law for the phase diagram in the temperature-chemical potential plane is derived.
[ { "created": "Tue, 6 Jul 1999 19:10:32 GMT", "version": "v1" } ]
2007-05-23
[ [ "Brower", "R. C.", "" ], [ "McGreevy", "J.", "" ], [ "Tan", "C-I", "" ] ]
Using generic properties of string theories, we show how interesting non-perturbative features of QCD can be exploited in heavy ion collisions. In particular, a generalized "semi-circle" law for the phase diagram in the temperature-chemical potential plane is derived.
hep-ph/0107024
Roberto Casalbuoni
R. Casalbuoni, R. Gatto, M. Mannarelli and G. Nardulli
Effective gluon interactions in the Colour Superconductive Phase of two flavor QCD
LaTeX, p 17, 4 figures. Final version to be published in Phys. Lett. B. Several corrections have been done and some point clarified
Phys.Lett. B524 (2002) 144-152
10.1016/S0370-2693(01)01370-3
null
hep-ph astro-ph hep-th nucl-th
null
The gluon self-energies and dispersion laws in the color superconducting phase of QCD with two massless flavors are calculated using the effective theory near the Fermi surface. These quantities are calculated at zero temperature for all the eight gluons, those of the remaining SU(2) color group and those corresponding to the broken generators. The construction of the effective interaction is completed with the one loop calculation of the three- and four-point gluon interactions.
[ { "created": "Tue, 3 Jul 2001 15:51:00 GMT", "version": "v1" }, { "created": "Tue, 20 Nov 2001 17:30:13 GMT", "version": "v2" } ]
2009-11-07
[ [ "Casalbuoni", "R.", "" ], [ "Gatto", "R.", "" ], [ "Mannarelli", "M.", "" ], [ "Nardulli", "G.", "" ] ]
The gluon self-energies and dispersion laws in the color superconducting phase of QCD with two massless flavors are calculated using the effective theory near the Fermi surface. These quantities are calculated at zero temperature for all the eight gluons, those of the remaining SU(2) color group and those corresponding to the broken generators. The construction of the effective interaction is completed with the one loop calculation of the three- and four-point gluon interactions.
1608.07145
Yue Jiang
Si-chen Li, Yue Jiang, Tian-hong Wang, Qiang Li, Zhi-hui Wang, Guo-Li Wang
Semi-leptonic Production of $D_{sJ}(3040)$ and $D_J(3000)$ in $B_s$ and $B$ Decays
17 pages, 4 figures
null
10.1142/S0217732317500134
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we study the productions of the newly detected states $D_{sJ}(3040)$ and $D_J(3000)$ observed by BABAR Collaboration and LHCb Collaboration. We assume these states to be the $D_s(2P)$ and $D(2P)$ states with the quantum number $J^P=1^+$ in our work. The results of improved Bethe-Salpeter method indicate that the semi-leptonic decays via $B_s$ and $B$ into $D_{sJ}(3040)$ and $D_J(3000)$ have considerable branching ratios, for example, Br($\bar{B}_s^0 \rightarrow D{_{sJ}^+}(3040)e^-\bar{\nu}{_e}$)=$5.79\times10^{-4}$, Br($\bar{B}^0\rightarrow D_{J}^+(3000)e^-\bar{\nu}{_e}$)=$2.63\times10^{-4}$, which shows that these semi-leptonic decays can be accessible in experiments.
[ { "created": "Thu, 25 Aug 2016 13:49:23 GMT", "version": "v1" }, { "created": "Tue, 30 Aug 2016 14:09:36 GMT", "version": "v2" } ]
2017-02-01
[ [ "Li", "Si-chen", "" ], [ "Jiang", "Yue", "" ], [ "Wang", "Tian-hong", "" ], [ "Li", "Qiang", "" ], [ "Wang", "Zhi-hui", "" ], [ "Wang", "Guo-Li", "" ] ]
In this paper, we study the productions of the newly detected states $D_{sJ}(3040)$ and $D_J(3000)$ observed by BABAR Collaboration and LHCb Collaboration. We assume these states to be the $D_s(2P)$ and $D(2P)$ states with the quantum number $J^P=1^+$ in our work. The results of improved Bethe-Salpeter method indicate that the semi-leptonic decays via $B_s$ and $B$ into $D_{sJ}(3040)$ and $D_J(3000)$ have considerable branching ratios, for example, Br($\bar{B}_s^0 \rightarrow D{_{sJ}^+}(3040)e^-\bar{\nu}{_e}$)=$5.79\times10^{-4}$, Br($\bar{B}^0\rightarrow D_{J}^+(3000)e^-\bar{\nu}{_e}$)=$2.63\times10^{-4}$, which shows that these semi-leptonic decays can be accessible in experiments.
hep-ph/0412006
Dariusz Prorok
Dariusz Prorok
The transverse energy per charged particle estimates in the framework of a statistical model
1 figure (included), 4 pages, To appear in the proceedings of 18th Nuclear Physics Division Conference: Phase Transitions in Strongly Interacting Matter, Prague, Czech Republic, 23-29 Aug 2004
Nucl.Phys. A749 (2005) 194
10.1016/j.nuclphysa.2004.12.033
null
hep-ph
null
The transverse energies and the charged particle multiplicities at midrapidity as well as their ratio, $dE_{T}/d\eta\mid_{mid} / dN_{ch}/d\eta|_{mid}$, are evaluated in a statistical model with expansion for the wide range of heavy-ion collisions, from AGS to RHIC at $\sqrt{s_{NN}}=200$ GeV. Full description of decays of hadron resonances is applied in calculations of both $dE_{T}/d\eta|_{mid}$ and $dN_{ch}/d\eta|_{mid}$. The predictions of the model at the freeze-out parameters, established independently from observed particle yields and $p_{T}$ spectra, agree well with the experimental data.
[ { "created": "Wed, 1 Dec 2004 11:03:22 GMT", "version": "v1" } ]
2009-11-10
[ [ "Prorok", "Dariusz", "" ] ]
The transverse energies and the charged particle multiplicities at midrapidity as well as their ratio, $dE_{T}/d\eta\mid_{mid} / dN_{ch}/d\eta|_{mid}$, are evaluated in a statistical model with expansion for the wide range of heavy-ion collisions, from AGS to RHIC at $\sqrt{s_{NN}}=200$ GeV. Full description of decays of hadron resonances is applied in calculations of both $dE_{T}/d\eta|_{mid}$ and $dN_{ch}/d\eta|_{mid}$. The predictions of the model at the freeze-out parameters, established independently from observed particle yields and $p_{T}$ spectra, agree well with the experimental data.
1003.2309
Matteo Giordano
Matteo Giordano and Robi Peschanski
High Energy Bounds on Soft N=4 SYM Amplitudes from AdS/CFT
25 pages, 3 eps figures
JHEP 1005:037,2010
10.1007/JHEP05(2010)037
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the AdS/CFT correspondence, we study the high-energy behavior of colorless dipole elastic scattering amplitudes in N=4 SYM gauge theory through the Wilson loop correlator formalism and Euclidean to Minkowskian analytic continuation. The purely elastic behavior obtained at large impact-parameter L, through duality from disconnected AdS_5 minimal surfaces beyond the Gross-Ooguri transition point, is combined with unitarity and analyticity constraints in the central region. In this way we obtain an absolute bound on the high-energy behavior of the forward scattering amplitude due to the graviton interaction between minimal surfaces in the bulk. The dominant "Pomeron" intercept is bounded by alpha less than or equal to 11/7 using the AdS/CFT constraint of a weak gravitational field in the bulk. Assuming the elastic eikonal approximation in a larger impact-parameter range gives alpha between 4/3 and 11/7. The actual intercept becomes 4/3 if one assumes the elastic eikonal approximation within its maximally allowed range L larger than exp{Y/3}, where Y is the total rapidity. Subleading AdS/CFT contributions at large impact-parameter due to the other d=10 supergravity fields are obtained. A divergence in the real part of the tachyonic KK scalar is cured by analyticity but signals the need for a theoretical completion of the AdS/CFT scheme.
[ { "created": "Thu, 11 Mar 2010 11:35:16 GMT", "version": "v1" }, { "created": "Wed, 15 Sep 2010 16:39:16 GMT", "version": "v2" } ]
2010-09-16
[ [ "Giordano", "Matteo", "" ], [ "Peschanski", "Robi", "" ] ]
Using the AdS/CFT correspondence, we study the high-energy behavior of colorless dipole elastic scattering amplitudes in N=4 SYM gauge theory through the Wilson loop correlator formalism and Euclidean to Minkowskian analytic continuation. The purely elastic behavior obtained at large impact-parameter L, through duality from disconnected AdS_5 minimal surfaces beyond the Gross-Ooguri transition point, is combined with unitarity and analyticity constraints in the central region. In this way we obtain an absolute bound on the high-energy behavior of the forward scattering amplitude due to the graviton interaction between minimal surfaces in the bulk. The dominant "Pomeron" intercept is bounded by alpha less than or equal to 11/7 using the AdS/CFT constraint of a weak gravitational field in the bulk. Assuming the elastic eikonal approximation in a larger impact-parameter range gives alpha between 4/3 and 11/7. The actual intercept becomes 4/3 if one assumes the elastic eikonal approximation within its maximally allowed range L larger than exp{Y/3}, where Y is the total rapidity. Subleading AdS/CFT contributions at large impact-parameter due to the other d=10 supergravity fields are obtained. A divergence in the real part of the tachyonic KK scalar is cured by analyticity but signals the need for a theoretical completion of the AdS/CFT scheme.
1409.7317
Chuan-Ren Chen
Qing-Hong Cao, Chuan-Ren Chen and Ti Gong
Leptophilic Dark Matter and AMS-02 Cosmic-ray Positron Flux
11 pages, 5 figures
Chin. J. Phys. 55 (2016) 10
10.1016/j.cjph.2016.11.006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
With the measurement of positron flux published recently by AMS-02 collaboration, we show how the leptophilic dark matter fits the observation. We obtain the percentages of different products of dark matter annihilation that can best describe the flux of high energy positrons observed by AMS. We show that dark matter annihilates predominantly into $\tau\tau$ pair, while both $ee$ and $\mu\mu$ final states should be less than $20\%$. When gauge boson final states are included, the best branching ratio of needed $\tau\tau$ mode reduces.
[ { "created": "Thu, 25 Sep 2014 16:25:41 GMT", "version": "v1" } ]
2017-03-16
[ [ "Cao", "Qing-Hong", "" ], [ "Chen", "Chuan-Ren", "" ], [ "Gong", "Ti", "" ] ]
With the measurement of positron flux published recently by AMS-02 collaboration, we show how the leptophilic dark matter fits the observation. We obtain the percentages of different products of dark matter annihilation that can best describe the flux of high energy positrons observed by AMS. We show that dark matter annihilates predominantly into $\tau\tau$ pair, while both $ee$ and $\mu\mu$ final states should be less than $20\%$. When gauge boson final states are included, the best branching ratio of needed $\tau\tau$ mode reduces.
1702.07716
Wei Xue
James M. Cline, Hongwan Liu, Tracy R. Slatyer and Wei Xue
Enabling Forbidden Dark Matter
12 pages, 8 figures. Updated to match version to be published in PRD. Minor corrections to the cross sections and the Boltzmann equations have been made. More detailed discussions of the secluded case, the Boltzmann equations and the computation of the cross sections have been included
Phys. Rev. D 96, 083521 (2017)
10.1103/PhysRevD.96.083521
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The thermal relic density of dark matter is conventionally set by two-body annihilations. We point out that in many simple models, $3 \to 2$ annihilations can play an important role in determining the relic density over a broad range of model parameters. This occurs when the two-body annihilation is kinematically forbidden, but the $3\to 2$ process is allowed; we call this scenario "Not-Forbidden Dark Matter". We illustrate this mechanism for a vector portal dark matter model, showing that for a dark matter mass of $m_\chi \sim \text{MeV - 10 GeV}$, $3 \to 2$ processes not only lead to the observed relic density, but also imply a self-interaction cross section that can solve the cusp/core problem. This can be accomplished while remaining consistent with stringent CMB constraints on light dark matter, and can potentially be discovered at future direct detection experiments.
[ { "created": "Fri, 24 Feb 2017 19:00:00 GMT", "version": "v1" }, { "created": "Fri, 13 Oct 2017 17:13:16 GMT", "version": "v2" } ]
2017-10-25
[ [ "Cline", "James M.", "" ], [ "Liu", "Hongwan", "" ], [ "Slatyer", "Tracy R.", "" ], [ "Xue", "Wei", "" ] ]
The thermal relic density of dark matter is conventionally set by two-body annihilations. We point out that in many simple models, $3 \to 2$ annihilations can play an important role in determining the relic density over a broad range of model parameters. This occurs when the two-body annihilation is kinematically forbidden, but the $3\to 2$ process is allowed; we call this scenario "Not-Forbidden Dark Matter". We illustrate this mechanism for a vector portal dark matter model, showing that for a dark matter mass of $m_\chi \sim \text{MeV - 10 GeV}$, $3 \to 2$ processes not only lead to the observed relic density, but also imply a self-interaction cross section that can solve the cusp/core problem. This can be accomplished while remaining consistent with stringent CMB constraints on light dark matter, and can potentially be discovered at future direct detection experiments.
hep-ph/0301067
Fritz W. Bopp
Fritz W. Bopp and Johannes Ranft
Charge Fluctuation in Heavy Ion Collisions
6 pages, 5 figures, Talk given at the Symposium on Multiparticle Dynamics, Alushta, Ukraine, Sept. 2002
null
10.1142/9789812704962_0007
SI-2002-05
hep-ph
null
Charge fluctuations observed in early fixed-target proton-proton experiments are consistent with string models. In central heavy ion events the picture can change in two ways: strings can interact and find new ways to hadronize or they can be effectively inactivated to lose their dynamical role as ordering mechanism. Widely different charge fluctuations can be expected. The dispersion of the charges in a central rapidity box is an advantageous measure. In an explicit Dual-Parton-Model calculation using the DPMJET code and a randomized modification to simulated charge equilibrium, various energies and different nuclear sizes were considered. Local fluctuations were found to be a serious problem. However, for large enough detection regions charged particle fluctuations can provide a clear signal reflecting the basic dynamics of central heavy ion processes.
[ { "created": "Fri, 10 Jan 2003 17:30:19 GMT", "version": "v1" } ]
2017-08-23
[ [ "Bopp", "Fritz W.", "" ], [ "Ranft", "Johannes", "" ] ]
Charge fluctuations observed in early fixed-target proton-proton experiments are consistent with string models. In central heavy ion events the picture can change in two ways: strings can interact and find new ways to hadronize or they can be effectively inactivated to lose their dynamical role as ordering mechanism. Widely different charge fluctuations can be expected. The dispersion of the charges in a central rapidity box is an advantageous measure. In an explicit Dual-Parton-Model calculation using the DPMJET code and a randomized modification to simulated charge equilibrium, various energies and different nuclear sizes were considered. Local fluctuations were found to be a serious problem. However, for large enough detection regions charged particle fluctuations can provide a clear signal reflecting the basic dynamics of central heavy ion processes.
2205.04824
Rinku Maji
George Lazarides, Rinku Maji, Rishav Roshan, Qaisar Shafi
Heavier $W$ boson, dark matter and gravitational waves from strings in an $SO(10)$ axion model
20 pages, 6 figures, published version
Phys. Rev. D 106 (2022) 5, 055009
10.1103/PhysRevD.106.055009
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inspired by the recent determination of the $W$-boson mass by the CDF collaboration, we revisit an $SO(10)$ axion model in which a scalar $SU(2)_L$ triplet field with zero hypercharge is known to acquire a non-zero VEV through its mixing with the Standard Model Higgs doublet. The triplet VEV provides a sizable contribution to the $W$ mass, which helps in significantly lowering the $7\sigma$ discrepancy between the Standard Model prediction and the higher CDF value for $m_W$. We show that the relatively light triplet mass ($\sim (1-50)$ TeV) is compatible with gauge coupling unification and observable proton decay. An unbroken $Z_2$ gauge symmetry, coupled with the presence of two fermionic $10$-plets required to resolve the axion domain wall problem, means that both axions and a stable intermediate mass ($\sim 10^9-10^{10}$ GeV) fermion are plausible dark matter candidates. We also display the gravitational wave spectrum from the intermediate scale topologically stable cosmic strings predicted by the model.
[ { "created": "Tue, 10 May 2022 11:54:17 GMT", "version": "v1" }, { "created": "Wed, 7 Sep 2022 08:36:50 GMT", "version": "v2" } ]
2022-09-08
[ [ "Lazarides", "George", "" ], [ "Maji", "Rinku", "" ], [ "Roshan", "Rishav", "" ], [ "Shafi", "Qaisar", "" ] ]
Inspired by the recent determination of the $W$-boson mass by the CDF collaboration, we revisit an $SO(10)$ axion model in which a scalar $SU(2)_L$ triplet field with zero hypercharge is known to acquire a non-zero VEV through its mixing with the Standard Model Higgs doublet. The triplet VEV provides a sizable contribution to the $W$ mass, which helps in significantly lowering the $7\sigma$ discrepancy between the Standard Model prediction and the higher CDF value for $m_W$. We show that the relatively light triplet mass ($\sim (1-50)$ TeV) is compatible with gauge coupling unification and observable proton decay. An unbroken $Z_2$ gauge symmetry, coupled with the presence of two fermionic $10$-plets required to resolve the axion domain wall problem, means that both axions and a stable intermediate mass ($\sim 10^9-10^{10}$ GeV) fermion are plausible dark matter candidates. We also display the gravitational wave spectrum from the intermediate scale topologically stable cosmic strings predicted by the model.
1412.4677
Andreas Papaefstathiou
Andreas Papaefstathiou
How-to: Write a parton-level Monte Carlo event generator
Matches published version. Exercises and solutions at https://apapaefs.web.cern.ch/apapaefs/mchowto.html. Given as part of the "Advanced Scientific Computing Workshop" at ETH Z\"urich in July 2014
Eur.Phys.J.Plus 135 (2020) 6, 497
10.1140/epjp/s13360-020-00499-1
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
This article provides an introduction to the principles of particle physics event generators that are based on the Monte Carlo method. Following some preliminaries, instructions on how to build a basic parton-level Monte Carlo event generator for the hard interaction are given through exercises. Indications on how to proceed to full event simulations are given.
[ { "created": "Mon, 15 Dec 2014 17:07:06 GMT", "version": "v1" }, { "created": "Wed, 15 Jul 2020 16:37:16 GMT", "version": "v2" } ]
2020-07-16
[ [ "Papaefstathiou", "Andreas", "" ] ]
This article provides an introduction to the principles of particle physics event generators that are based on the Monte Carlo method. Following some preliminaries, instructions on how to build a basic parton-level Monte Carlo event generator for the hard interaction are given through exercises. Indications on how to proceed to full event simulations are given.
1202.2866
Reinard Primulando
Wolfgang Altmannshofer, Reinard Primulando, Chiu-Tien Yu, and Felix Yu
New Physics Models of Direct CP Violation in Charm Decays
24 pages, 13 figures. v2: typos corrected, reference added, published version
null
10.1007/JHEP04(2012)049
FERMILAB-PUB-12-034-T
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In view of the recent LHCb measurement of Delta A_CP, the difference between the time-integrated CP asymmetries in D --> K+K- and D --> pi+pi- decays, we perform a comparative study of the possible impact of New Physics degrees of freedom on the direct CP asymmetries in singly Cabibbo suppressed D meson decays. We systematically discuss scenarios with a minimal set of new degrees of freedom that have renormalizable couplings to the SM particles and that are heavy enough such that their effects on the D meson decays can be described by local operators. We take into account both constraints from low energy flavor observables, in particular D0-D0bar mixing, and from direct searches. While models that explain the large measured value for Delta A_CP with chirally enhanced chromomagnetic penguins are least constrained, we identify a few viable models that contribute to the D meson decays at tree level or through loop induced QCD penguins. We emphasize that such models motivate direct searches at the LHC.
[ { "created": "Mon, 13 Feb 2012 21:04:03 GMT", "version": "v1" }, { "created": "Fri, 30 Mar 2012 16:46:38 GMT", "version": "v2" } ]
2015-06-04
[ [ "Altmannshofer", "Wolfgang", "" ], [ "Primulando", "Reinard", "" ], [ "Yu", "Chiu-Tien", "" ], [ "Yu", "Felix", "" ] ]
In view of the recent LHCb measurement of Delta A_CP, the difference between the time-integrated CP asymmetries in D --> K+K- and D --> pi+pi- decays, we perform a comparative study of the possible impact of New Physics degrees of freedom on the direct CP asymmetries in singly Cabibbo suppressed D meson decays. We systematically discuss scenarios with a minimal set of new degrees of freedom that have renormalizable couplings to the SM particles and that are heavy enough such that their effects on the D meson decays can be described by local operators. We take into account both constraints from low energy flavor observables, in particular D0-D0bar mixing, and from direct searches. While models that explain the large measured value for Delta A_CP with chirally enhanced chromomagnetic penguins are least constrained, we identify a few viable models that contribute to the D meson decays at tree level or through loop induced QCD penguins. We emphasize that such models motivate direct searches at the LHC.
1704.08879
Jilberto Zamora-Sa\'a
Felipe Rojas Abatte, Jilberto Zamora-Saa, Oscar Castillo-Felisola, Bastian Diaz and Alfonso R. Zerwekh
Corrections to (pseudo)scalars decay into a fermion pair from gravitational torsion
Accepted for publication in APPB
ACTA PHYSICA POLONICA B, Vol. 49 (2018) , No 1
10.5506/APhysPolB.49.41
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the contribution of the torsion-descendent four-fermion contact interaction to the decay width of a neutral (pseudo)scalar field into a fermion pair. This new interaction comes from the existence of gravitational torsion in models with extra dimensions. Additionally, we exemplify the formalism with two examples: first, the variation of the considered branching ratio of the Higgs in the context of the standard model, and second the proper variations of the scalar and pseudo scalar fields of the type II-1 two Higgs doublets model.
[ { "created": "Fri, 28 Apr 2017 11:23:48 GMT", "version": "v1" }, { "created": "Tue, 6 Jun 2017 08:45:13 GMT", "version": "v2" }, { "created": "Thu, 23 Nov 2017 16:32:47 GMT", "version": "v3" } ]
2018-02-01
[ [ "Abatte", "Felipe Rojas", "" ], [ "Zamora-Saa", "Jilberto", "" ], [ "Castillo-Felisola", "Oscar", "" ], [ "Diaz", "Bastian", "" ], [ "Zerwekh", "Alfonso R.", "" ] ]
We study the contribution of the torsion-descendent four-fermion contact interaction to the decay width of a neutral (pseudo)scalar field into a fermion pair. This new interaction comes from the existence of gravitational torsion in models with extra dimensions. Additionally, we exemplify the formalism with two examples: first, the variation of the considered branching ratio of the Higgs in the context of the standard model, and second the proper variations of the scalar and pseudo scalar fields of the type II-1 two Higgs doublets model.
hep-ph/0012042
Pierre Marage
P. Marage
Diffraction at HERA and Prospects with H1
Talk given at the DIFFRACTION 2000 Workshop, Cetraro, Italy, Sept. 2000; 5 pages, 5 figures, 26 ref
Nucl.Phys.Proc.Suppl. 99A (2001) 139-143
10.1016/S0920-5632(01)01322-6
null
hep-ph
null
In the context of the tremendous progress achieved at HERA in diffraction and the need for a new level of statistical and systematic precision, the new very large acceptance forward spectrometer planned by H1 (VFPS) is presented and the physics issues are stressed.
[ { "created": "Tue, 5 Dec 2000 08:09:17 GMT", "version": "v1" } ]
2009-10-31
[ [ "Marage", "P.", "" ] ]
In the context of the tremendous progress achieved at HERA in diffraction and the need for a new level of statistical and systematic precision, the new very large acceptance forward spectrometer planned by H1 (VFPS) is presented and the physics issues are stressed.
hep-ph/0104223
Marco Radici
S. Boffi, M. Radici, L. Glozman, R.F. Wagenbrunn, W. Plessas and W. Klink
Electroweak properties of baryons in a covariant chiral quark model
Proceedings of the Conference N*2001, Mainz; 4 pages, 3 figures included in eps format; World Scientific style file included
null
10.1142/9789812810878_0031
null
hep-ph
null
The proton and neutron electromagnetic form factors and the nucleon axial form factor have been calculated in the Goldstone-boson exchange constituent-quark model within the point-form approach to relativistic quantum mechanics. The results, obtained without any adjustable parameter nor quark form factors, are, due to the dramatic effects of the boost required by the covariant treatment, in striking agreement with the data.
[ { "created": "Mon, 23 Apr 2001 10:40:54 GMT", "version": "v1" }, { "created": "Thu, 26 Apr 2001 06:36:40 GMT", "version": "v2" } ]
2017-08-23
[ [ "Boffi", "S.", "" ], [ "Radici", "M.", "" ], [ "Glozman", "L.", "" ], [ "Wagenbrunn", "R. F.", "" ], [ "Plessas", "W.", "" ], [ "Klink", "W.", "" ] ]
The proton and neutron electromagnetic form factors and the nucleon axial form factor have been calculated in the Goldstone-boson exchange constituent-quark model within the point-form approach to relativistic quantum mechanics. The results, obtained without any adjustable parameter nor quark form factors, are, due to the dramatic effects of the boost required by the covariant treatment, in striking agreement with the data.
2110.15026
Mahmoud Nassar Hanafy
D. M. Habashy, Mahmoud Y. El-Bakry, Werner Scheinast and Mahmoud Hanafy
Entropy per rapidity in Pb-Pb central collisions using Thermal and Artificial neural network(ANN) models at LHC energies
null
null
10.1088/1674-1137/ac5f9d
null
hep-ph
http://creativecommons.org/licenses/by-nc-sa/4.0/
The entropy per rapidity $d S/d y$ produced in central Pb-Pb ultra-relativistic nuclear collisions at LHC energies is calculated using experimentally observed identified particle spectra and source radii estimated from Hanbury Brown-Twiss (HBT) for particles, $\pi$, $k$, $p$, $\Lambda$, $\Omega$, and $\bar{\Sigma}$, and $\pi$, $k$, $p$, $\Lambda$ and $K_s^0$ at $ \sqrt{s}$ $=2.76$ and $5.02$ TeV, respectively. Artificial neural network (ANN) simulation model is used to estimate the entropy per rapidity $d S/d y$ at the considered energies. The simulation results are compared with equivalent experimental data, and good agreement is achieved. A mathematical equation describes experimental data is obtained. Extrapolating the transverse momentum spectra at $p_T$ $=0$ is required to calculate $d S/d y$ thus we use two different fitting functions, Tsallis distribution and the Hadron Resonance Gas (HRG) model. The success of ANN model to describe the experimental measurements will imply further prediction for the entropy per rapidity in the absence of the experiment.
[ { "created": "Thu, 28 Oct 2021 11:20:19 GMT", "version": "v1" } ]
2022-07-13
[ [ "Habashy", "D. M.", "" ], [ "El-Bakry", "Mahmoud Y.", "" ], [ "Scheinast", "Werner", "" ], [ "Hanafy", "Mahmoud", "" ] ]
The entropy per rapidity $d S/d y$ produced in central Pb-Pb ultra-relativistic nuclear collisions at LHC energies is calculated using experimentally observed identified particle spectra and source radii estimated from Hanbury Brown-Twiss (HBT) for particles, $\pi$, $k$, $p$, $\Lambda$, $\Omega$, and $\bar{\Sigma}$, and $\pi$, $k$, $p$, $\Lambda$ and $K_s^0$ at $ \sqrt{s}$ $=2.76$ and $5.02$ TeV, respectively. Artificial neural network (ANN) simulation model is used to estimate the entropy per rapidity $d S/d y$ at the considered energies. The simulation results are compared with equivalent experimental data, and good agreement is achieved. A mathematical equation describes experimental data is obtained. Extrapolating the transverse momentum spectra at $p_T$ $=0$ is required to calculate $d S/d y$ thus we use two different fitting functions, Tsallis distribution and the Hadron Resonance Gas (HRG) model. The success of ANN model to describe the experimental measurements will imply further prediction for the entropy per rapidity in the absence of the experiment.
1907.02490
Brett D. Altschul
Brett Altschul and Matthias R. Schindler
The Lorentz- and CPT-Violating Standard Model Extension in Chiral Perturbation Theory
33 pages
Phys. Rev. D 100, 075031 (2019)
10.1103/PhysRevD.100.075031
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Lorentz and CPT violation in hadronic physics must be tied to symmetry violations at the underlying quark and gluon level. Chiral perturbation theory provides a method for translating novel operators that may appear in the Lagrange density for color-charged parton fields into equivalent forms for effective theories at the meson and baryon levels. We extend the application of this technique to the study of Lorentz-violating and potentially CPT-violating operators from the minimal standard model extension. For dimension-4 operators, there are nontrivial relations between the coefficients of baryon-level operators related to underlying quark and gluon operators with the same Lorentz structures. Moreover, in the mapping of the dimension-3 operators from the quark and gluon level to the hadron level (considered here for the first time), many of the hadronic observables contain no new low-energy coupling constants at all, which makes it possible to make direct translations of bounds derived using experiments on one kind of hadron into bounds in a completely different corner of the hadronic sector. A notable consequence of this is bounds (at $10^{-15}$-$10^{-20}$ GeV levels) on differences $a^{\mu}_{B}-a^{\mu}_{B'}$ of Lorentz and CPT violation coefficients for $SU(3)_{f}$ octet baryons that differ in their structure by the replacement of a single valance $d$ quark by a $s$ quark. Never before has there been any proposal for how these kinds of differences could be constrained.
[ { "created": "Thu, 4 Jul 2019 17:00:30 GMT", "version": "v1" }, { "created": "Wed, 23 Oct 2019 15:07:33 GMT", "version": "v2" } ]
2019-10-24
[ [ "Altschul", "Brett", "" ], [ "Schindler", "Matthias R.", "" ] ]
Lorentz and CPT violation in hadronic physics must be tied to symmetry violations at the underlying quark and gluon level. Chiral perturbation theory provides a method for translating novel operators that may appear in the Lagrange density for color-charged parton fields into equivalent forms for effective theories at the meson and baryon levels. We extend the application of this technique to the study of Lorentz-violating and potentially CPT-violating operators from the minimal standard model extension. For dimension-4 operators, there are nontrivial relations between the coefficients of baryon-level operators related to underlying quark and gluon operators with the same Lorentz structures. Moreover, in the mapping of the dimension-3 operators from the quark and gluon level to the hadron level (considered here for the first time), many of the hadronic observables contain no new low-energy coupling constants at all, which makes it possible to make direct translations of bounds derived using experiments on one kind of hadron into bounds in a completely different corner of the hadronic sector. A notable consequence of this is bounds (at $10^{-15}$-$10^{-20}$ GeV levels) on differences $a^{\mu}_{B}-a^{\mu}_{B'}$ of Lorentz and CPT violation coefficients for $SU(3)_{f}$ octet baryons that differ in their structure by the replacement of a single valance $d$ quark by a $s$ quark. Never before has there been any proposal for how these kinds of differences could be constrained.
hep-ph/0508301
Yoshio Koide
Yoshio Koide
Seesaw Mass Matrix Model of Quarks and Leptons with Flavor-Triplet Higgs Scalars
version accepted by EPJC
Eur.Phys.J.C48:223-228,2006
10.1140/epjc/s10052-006-0009-5
US-05-04R
hep-ph
null
In a seesaw mass matrix model M_f = m_L M_F^{-1} m_R^\dagger with a universal structure of m_L \propto m_R, as the origin of m_L (m_R) for quarks and eptons, flavor-triplet Higgs scalars whose vacuum expectation values v_i are proportional to the square roots of the charged lepton masses m_{ei}, i.e. v_i \propto \sqrt{m_{ei}}, are assumed. Then, it is investigated whether such a model can explain the observed neutrino masses and mixings (and also quark masses and mixings) or not.
[ { "created": "Tue, 30 Aug 2005 08:12:20 GMT", "version": "v1" }, { "created": "Fri, 16 Sep 2005 09:27:51 GMT", "version": "v2" }, { "created": "Thu, 22 Sep 2005 06:18:10 GMT", "version": "v3" }, { "created": "Sat, 29 Jul 2006 08:38:54 GMT", "version": "v4" } ]
2009-01-07
[ [ "Koide", "Yoshio", "" ] ]
In a seesaw mass matrix model M_f = m_L M_F^{-1} m_R^\dagger with a universal structure of m_L \propto m_R, as the origin of m_L (m_R) for quarks and eptons, flavor-triplet Higgs scalars whose vacuum expectation values v_i are proportional to the square roots of the charged lepton masses m_{ei}, i.e. v_i \propto \sqrt{m_{ei}}, are assumed. Then, it is investigated whether such a model can explain the observed neutrino masses and mixings (and also quark masses and mixings) or not.
1705.08443
Zhong-Bo Kang
Zhong-Bo Kang, Xiaohui Liu, Felix Ringer, Hongxi Xing
The transverse momentum distribution of hadrons within jets
28 pages, 3 figures, published version
JHEP 1711 (2017) 068
10.1007/JHEP11(2017)068
null
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the transverse momentum distribution of hadrons within jets, where the transverse momentum is defined with respect to the standard jet axis. We consider the case where the jet substructure measurement is performed for an inclusive jet sample $pp\to\text{jet}+X$. We demonstrate that this observable provides new opportunities to study transverse momentum dependent fragmentation functions (TMDFFs) which are currently poorly constrained from data, especially for gluons. The factorization of the cross section is obtained within Soft Collinear Effective Theory (SCET), and we show that the relevant TMDFFs are the same as for the more traditional processes semi-inclusive deep inelastic scattering (SIDIS) and electron-positron annihilation. Different than in SIDIS, the observable for the in-jet fragmentation does not depend on TMD parton distribution functions which allows for a cleaner and more direct probe of TMDFFs. We present numerical results and compare to available data from the LHC.
[ { "created": "Tue, 23 May 2017 17:57:46 GMT", "version": "v1" }, { "created": "Tue, 14 Nov 2017 22:22:27 GMT", "version": "v2" } ]
2017-11-16
[ [ "Kang", "Zhong-Bo", "" ], [ "Liu", "Xiaohui", "" ], [ "Ringer", "Felix", "" ], [ "Xing", "Hongxi", "" ] ]
We study the transverse momentum distribution of hadrons within jets, where the transverse momentum is defined with respect to the standard jet axis. We consider the case where the jet substructure measurement is performed for an inclusive jet sample $pp\to\text{jet}+X$. We demonstrate that this observable provides new opportunities to study transverse momentum dependent fragmentation functions (TMDFFs) which are currently poorly constrained from data, especially for gluons. The factorization of the cross section is obtained within Soft Collinear Effective Theory (SCET), and we show that the relevant TMDFFs are the same as for the more traditional processes semi-inclusive deep inelastic scattering (SIDIS) and electron-positron annihilation. Different than in SIDIS, the observable for the in-jet fragmentation does not depend on TMD parton distribution functions which allows for a cleaner and more direct probe of TMDFFs. We present numerical results and compare to available data from the LHC.
2312.17568
Zhi-Peng Xing
Zhi-Peng Xing, Yu Ji Shi, Jin Sun and Zhen-Xing Zhao
Light baryon in three quark picture light front approach and its application: hyperon weak radiative decays
15 pages, 2 figures, 5 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by recent experimental data on $\Sigma^+\to p\gamma$ at BESIII, we investigate a class of hyperon weak radiative decays. To estimate these processes, in our research, we employ a new type of light-front quark model with a three-quark picture for octet baryons. In the three-quark picture, with the use of $SU(3)_f$ and spin symmetries, we present a general form of the light front wave function for each octet baryon. By including contributions from the penguin diagram and W exchange diagram, we perform a complete calculation on the branching ratios ($Br$) and the asymmetry parameter ($\alpha$) for hyperon weak radiative decay processes. Our results are helpful for discovering additional hyperon weak radiative decay processes in experimental facilities, and our research will promote the theoretical study of baryons.
[ { "created": "Fri, 29 Dec 2023 11:38:45 GMT", "version": "v1" }, { "created": "Mon, 8 Jan 2024 05:52:12 GMT", "version": "v2" } ]
2024-01-09
[ [ "Xing", "Zhi-Peng", "" ], [ "Shi", "Yu Ji", "" ], [ "Sun", "Jin", "" ], [ "Zhao", "Zhen-Xing", "" ] ]
Motivated by recent experimental data on $\Sigma^+\to p\gamma$ at BESIII, we investigate a class of hyperon weak radiative decays. To estimate these processes, in our research, we employ a new type of light-front quark model with a three-quark picture for octet baryons. In the three-quark picture, with the use of $SU(3)_f$ and spin symmetries, we present a general form of the light front wave function for each octet baryon. By including contributions from the penguin diagram and W exchange diagram, we perform a complete calculation on the branching ratios ($Br$) and the asymmetry parameter ($\alpha$) for hyperon weak radiative decay processes. Our results are helpful for discovering additional hyperon weak radiative decay processes in experimental facilities, and our research will promote the theoretical study of baryons.
1107.1808
Wenhan Zhu Wenhan Zhu
Wenhan Zhu
Application of Jet Trimming in Boosted Higgs Search
5 pages,4 figures, presented in Pheno 2011
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the study of the $WH$ and $ZH$ search with the Higgs Boson decayed to $b\bar{b}$ at the Large Hadron Collider. The Higgs Boson and the Vector Boson are required to be boosted, and the Higgs Boson is reconstructed with Jet Trimming Technique. The statistical significance for 30$fb^{-1}$ data is 4.5 $\sigma$, which is comparable to the previous result.
[ { "created": "Sat, 9 Jul 2011 18:52:27 GMT", "version": "v1" } ]
2011-07-12
[ [ "Zhu", "Wenhan", "" ] ]
We present the study of the $WH$ and $ZH$ search with the Higgs Boson decayed to $b\bar{b}$ at the Large Hadron Collider. The Higgs Boson and the Vector Boson are required to be boosted, and the Higgs Boson is reconstructed with Jet Trimming Technique. The statistical significance for 30$fb^{-1}$ data is 4.5 $\sigma$, which is comparable to the previous result.
hep-ph/0509264
Marco Ruggieri
M. Ruggieri
Smeared gap equations in crystalline color superconductivity
10 pages; contribution to QCD@Workshop
null
10.1063/1.2163778
BA-TH 519/05
hep-ph
null
In the framework of HDET, we discuss an averaging procedure of the NJL quark-quark interaction lagrangian, treated in the mean field approximation, for the two flavor LOFF phase of QCD. This procedure gives results which are valid in domains where Ginzburg-Landau results may be questionable. We compute and compare the free energy for different LOFF crystalline structures.
[ { "created": "Fri, 23 Sep 2005 14:45:54 GMT", "version": "v1" } ]
2015-06-25
[ [ "Ruggieri", "M.", "" ] ]
In the framework of HDET, we discuss an averaging procedure of the NJL quark-quark interaction lagrangian, treated in the mean field approximation, for the two flavor LOFF phase of QCD. This procedure gives results which are valid in domains where Ginzburg-Landau results may be questionable. We compute and compare the free energy for different LOFF crystalline structures.
hep-ph/9903361
William Kilgore
William B. Kilgore (BNL), Walter T. Giele (FNAL)
Hadronic Three Jet Production at Next-to-Leading Order
6 pages, REVTeX, epsf, 3 figures, talk presented at DPF'99, UCLA, January 5-9, 1999
null
null
null
hep-ph
null
We report preliminary results for a next-to-leading order event generator for hadronic three jet production. We demonstrate the stability of the calculation and present preliminary results for the jet transverse energy spectra. This is the first calculation of three jet production at this order to include all parton sub-processes.
[ { "created": "Mon, 15 Mar 1999 22:20:49 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kilgore", "William B.", "", "BNL" ], [ "Giele", "Walter T.", "", "FNAL" ] ]
We report preliminary results for a next-to-leading order event generator for hadronic three jet production. We demonstrate the stability of the calculation and present preliminary results for the jet transverse energy spectra. This is the first calculation of three jet production at this order to include all parton sub-processes.
hep-ph/9604379
Giulio Mignola
A. Bottino, G. Mignola, M. Olechowski and S. Scopel
Relic neutralinos in a best-fitted MSSM
11 pages, LaTeX, 4 postscript figures appended as uuencode, gzipped, tarred files
Phys.Lett. B380 (1996) 308-316
10.1016/0370-2693(96)00531-X
CERN-TH/96-103, DFTT 17/96, GEF-Th-5/96
hep-ph astro-ph
null
We examine the properties of relic neutralinos in the regions of the parameter space selected by recent fits to all the electroweak observables within the Minimal Supersymmetric Standard Model. We discuss the relic neutralino cosmic abundance and the direct detection rates for these most likely supersymmetric configurations. We employ the relevant experimental bounds to constrain the set of the best-fit configurations and discuss the discovery potential of the direct search for relic neutralinos.
[ { "created": "Mon, 22 Apr 1996 09:47:23 GMT", "version": "v1" } ]
2009-10-28
[ [ "Bottino", "A.", "" ], [ "Mignola", "G.", "" ], [ "Olechowski", "M.", "" ], [ "Scopel", "S.", "" ] ]
We examine the properties of relic neutralinos in the regions of the parameter space selected by recent fits to all the electroweak observables within the Minimal Supersymmetric Standard Model. We discuss the relic neutralino cosmic abundance and the direct detection rates for these most likely supersymmetric configurations. We employ the relevant experimental bounds to constrain the set of the best-fit configurations and discuss the discovery potential of the direct search for relic neutralinos.
hep-ph/0602225
Hans-Werner Hammer
E. Epelbaum, H.-W. Hammer, Ulf-G. Mei{\ss}ner, and A. Nogga
More on the infrared renormalization group limit cycle in QCD
17 pages, 7 figures, discussion improved, results unchanged, version to appear in EPJC
Eur.Phys.J.C48:169-178,2006
10.1140/epjc/s10052-006-0004-x
HISKP-TH-06-06
hep-ph nucl-th
null
We present a detailed study of the recently conjectured infrared renormalization group limit cycle in QCD using chiral effective field theory. It was conjectured that small increases in the up and down quark masses can move QCD to the critical trajectory for an infrared limit cycle in the three-nucleon system. At the critical quark masses, the binding energies of the deuteron and its spin-singlet partner are tuned to zero and the triton has infinitely many excited states with an accumulation point at the three-nucleon threshold. We exemplify three parameter sets where this effect occurs at next-to-leading order in the chiral counting. For one of them, we study the structure of the three-nucleon system in detail using both chiral and contact effective field theories. Furthermore, we investigate the matching of the chiral and contact theories in the critical region and calculate the influence of the limit cycle on three-nucleon scattering observables.
[ { "created": "Fri, 24 Feb 2006 12:04:27 GMT", "version": "v1" }, { "created": "Wed, 5 Jul 2006 07:23:10 GMT", "version": "v2" } ]
2009-01-07
[ [ "Epelbaum", "E.", "" ], [ "Hammer", "H. -W.", "" ], [ "Meißner", "Ulf-G.", "" ], [ "Nogga", "A.", "" ] ]
We present a detailed study of the recently conjectured infrared renormalization group limit cycle in QCD using chiral effective field theory. It was conjectured that small increases in the up and down quark masses can move QCD to the critical trajectory for an infrared limit cycle in the three-nucleon system. At the critical quark masses, the binding energies of the deuteron and its spin-singlet partner are tuned to zero and the triton has infinitely many excited states with an accumulation point at the three-nucleon threshold. We exemplify three parameter sets where this effect occurs at next-to-leading order in the chiral counting. For one of them, we study the structure of the three-nucleon system in detail using both chiral and contact effective field theories. Furthermore, we investigate the matching of the chiral and contact theories in the critical region and calculate the influence of the limit cycle on three-nucleon scattering observables.
hep-ph/0502071
Michael Lublinsky
Alex Kovner and Michael Lublinsky
Remarks on High Energy Evolution
8 pages, references added. Version to appear in JHEP
JHEP 0503:001,2005
10.1088/1126-6708/2005/03/001
null
hep-ph
null
We make several remarks on the B-JIMWLK hierarchy. First, we present a simple and instructive derivation of this equation by considering an arbitrary projectile wave function with small number of valence gluons. We also generalize the equation by including corrections which incorporate effects of high density in the projectile wave function. Second, we systematically derive the dipole model approximation to the hierarchy. We show that in the dipole approximation the hierarchy has a simplifying property that allows its solution by solving the classical equation followed by averaging over the ensemble of initial conditions.
[ { "created": "Tue, 8 Feb 2005 01:02:59 GMT", "version": "v1" }, { "created": "Wed, 2 Mar 2005 18:43:08 GMT", "version": "v2" } ]
2010-02-03
[ [ "Kovner", "Alex", "" ], [ "Lublinsky", "Michael", "" ] ]
We make several remarks on the B-JIMWLK hierarchy. First, we present a simple and instructive derivation of this equation by considering an arbitrary projectile wave function with small number of valence gluons. We also generalize the equation by including corrections which incorporate effects of high density in the projectile wave function. Second, we systematically derive the dipole model approximation to the hierarchy. We show that in the dipole approximation the hierarchy has a simplifying property that allows its solution by solving the classical equation followed by averaging over the ensemble of initial conditions.
1303.7055
Xue Chang
Xue Chang, Chun Liu, Yi-Lei Tang
Phenomenological Aspects of R-parity Violating Supersymmetry with A Vector-like Extra Generation
30 pages, 1 table, 7 figures. Accepted for publication in Phys. Rev. D
Phys. Rev. D 87, 075012 (2013)
10.1103/PhysRevD.87.075012
null
hep-ph
http://creativecommons.org/licenses/by/3.0/
Phenomenological analysis to the R-parity violating supersymmetry with a vector-like extra generation is performed in detail. It is found that, via the trilinear couplings, the correct neutrino spectrum can be obtained. The Higgs mass rises to 125 GeV by new up-type Yukawa couplings of vector-like quarks with no need of very heavy superpartners. Phenomena of new heavy fermions at LHC are predicted.
[ { "created": "Thu, 28 Mar 2013 07:18:16 GMT", "version": "v1" }, { "created": "Sun, 31 Mar 2013 08:14:56 GMT", "version": "v2" } ]
2013-10-14
[ [ "Chang", "Xue", "" ], [ "Liu", "Chun", "" ], [ "Tang", "Yi-Lei", "" ] ]
Phenomenological analysis to the R-parity violating supersymmetry with a vector-like extra generation is performed in detail. It is found that, via the trilinear couplings, the correct neutrino spectrum can be obtained. The Higgs mass rises to 125 GeV by new up-type Yukawa couplings of vector-like quarks with no need of very heavy superpartners. Phenomena of new heavy fermions at LHC are predicted.
2407.00732
Albertus Hariwangsa Panuluh
Takuya Morozumi and Albertus Hariwangsa Panuluh
The third family quark mass hierarchy and FCNC in the universal seesaw model
45 pages, 2 figures, add references, correct typos; add subsubsection 6.1.1; to be published in PTEP
null
null
HUPD-2405
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We present the study of the quark sector of the universal seesaw model with $\mathrm{SU(2)_L \times SU(2)_R \times U(1)_{Y'}}$ gauge symmetry in the massless case of the two lightest quark families. This model aims to explain the mass hierarchy of the third family quark by introducing a vector-like quark (VLQ) partner for each quark. In this model, we introduce $\mathrm{SU(2)_L}$ and $\mathrm{SU(2)_R}$ Higgs doublets. We derive explicitly the Lagrangian for the quark sector, Higgs sector, and kinetic terms of the gauge fields, starting from the Lagrangian, which is invariant under $\mathrm{SU(2)_L \times SU(2)_R \times U(1)_{Y'}}$ gauge symmetry. At each stage of the symmetry breaking, we present the Lagrangian with the remaining gauge symmetry. Additionally, we investigate the flavor-changing neutral currents (FCNC) of Higgs ($h$) and $Z$-boson in the interaction with the top, heavy top, bottom, and heavy bottom quark.
[ { "created": "Sun, 30 Jun 2024 15:39:09 GMT", "version": "v1" }, { "created": "Fri, 5 Jul 2024 05:23:21 GMT", "version": "v2" }, { "created": "Fri, 9 Aug 2024 06:44:22 GMT", "version": "v3" } ]
2024-08-12
[ [ "Morozumi", "Takuya", "" ], [ "Panuluh", "Albertus Hariwangsa", "" ] ]
We present the study of the quark sector of the universal seesaw model with $\mathrm{SU(2)_L \times SU(2)_R \times U(1)_{Y'}}$ gauge symmetry in the massless case of the two lightest quark families. This model aims to explain the mass hierarchy of the third family quark by introducing a vector-like quark (VLQ) partner for each quark. In this model, we introduce $\mathrm{SU(2)_L}$ and $\mathrm{SU(2)_R}$ Higgs doublets. We derive explicitly the Lagrangian for the quark sector, Higgs sector, and kinetic terms of the gauge fields, starting from the Lagrangian, which is invariant under $\mathrm{SU(2)_L \times SU(2)_R \times U(1)_{Y'}}$ gauge symmetry. At each stage of the symmetry breaking, we present the Lagrangian with the remaining gauge symmetry. Additionally, we investigate the flavor-changing neutral currents (FCNC) of Higgs ($h$) and $Z$-boson in the interaction with the top, heavy top, bottom, and heavy bottom quark.
hep-ph/0103246
Yasuhiko Tsue
Y.Tsue (1), A.Koike (1), N.Ikezi (2) ((1)Kochi Univ. Japan (2)Nagoya Univ. Japan)
Time-Evolution of a Collective Meson Field by the Use of a Squeezed State
18 pages, 22 postscript figures, uses PTPTeX.sty
Prog.Theor.Phys. 106 (2001) 807-822
10.1143/PTP.106.807
null
hep-ph
null
A time-evolution of quantum meson fields is investigated in a linear sigma model by means of the time-dependent variational approach with a squeezed state. The chiral condensate, which is a mean field of the quantum meson fields, and quantum fluctuations around it are treated self-consistently in this approach. The attention is payed to the description of the relaxation process of the chiral condensate, where the energy stored in the mean field configuration flows to the fluctuation modes. It is shown that the quantum fluctuations play an important role to describe this relaxation process.
[ { "created": "Fri, 23 Mar 2001 01:05:06 GMT", "version": "v1" } ]
2009-11-07
[ [ "Tsue", "Y.", "" ], [ "Koike", "A.", "" ], [ "Ikezi", "N.", "" ] ]
A time-evolution of quantum meson fields is investigated in a linear sigma model by means of the time-dependent variational approach with a squeezed state. The chiral condensate, which is a mean field of the quantum meson fields, and quantum fluctuations around it are treated self-consistently in this approach. The attention is payed to the description of the relaxation process of the chiral condensate, where the energy stored in the mean field configuration flows to the fluctuation modes. It is shown that the quantum fluctuations play an important role to describe this relaxation process.
hep-ph/9809305
Colin Morningstar
C. Morningstar
News from the lattice
9 pages, LaTeX (4 figures), uses worldsci.sty. Summary talk given at the Third International Conference on Quark Confinement and the Hadron Spectrum, Jefferson Lab, USA, June 7-12, 1998
null
null
UCSD/PTH 98-27
hep-ph
null
A summary of some recent results from lattice simulations is presented. These include first calculations of the strangeness magnetic moment of the nucleon, three new studies of the gluon propagator, flux tube attraction in U(1) gauge theory, and the static-quark potential and its gluonic excitations.
[ { "created": "Tue, 8 Sep 1998 19:23:35 GMT", "version": "v1" } ]
2007-05-23
[ [ "Morningstar", "C.", "" ] ]
A summary of some recent results from lattice simulations is presented. These include first calculations of the strangeness magnetic moment of the nucleon, three new studies of the gluon propagator, flux tube attraction in U(1) gauge theory, and the static-quark potential and its gluonic excitations.
hep-ph/0701229
Yudi Santoso
J. L. Diaz-Cruz, John Ellis, Keith A. Olive, Yudi Santoso
On the Feasibility of a Stop NLSP in Gravitino Dark Matter Scenarios
31 pages, 14 figures
JHEP 0705:003,2007
10.1088/1126-6708/2007/05/003
CERN-PH-TH/2007-003, UMN-TH-2536/07, FTPI-MINN-07/03
hep-ph astro-ph hep-ex
null
We analyze the possibility that the lighter stop {\tilde t_1} could be the next-to-lightest supersymmetric particle (NLSP) in models where the gravitino is the lightest supersymmetric particle (LSP). We do not find any possibility for a stop NLSP in the constrained MSSM with universal input soft supersymmetry-breaking masses at the GUT scale (CMSSM), but do find small allowed regions in models with non-universal Higgs masses (NUHM). We discuss the cosmological evolution of stop hadrons. Most {\tilde t_1}qq `sbaryons' and the corresponding `antisbaryons' annihilate with conventional antibaryons and baryons into {\tilde t_1}{\bar q} `mesinos' and the corresponding `antimesinos', respectively, shortly after the quark-hadron transition in the early Universe, and most mesinos and antimesinos subsequently annihilate. As a result, insufficient metastable charged stop hadrons survive to alter Big Bang nucleosynthesis.
[ { "created": "Fri, 26 Jan 2007 21:55:38 GMT", "version": "v1" } ]
2009-11-13
[ [ "Diaz-Cruz", "J. L.", "" ], [ "Ellis", "John", "" ], [ "Olive", "Keith A.", "" ], [ "Santoso", "Yudi", "" ] ]
We analyze the possibility that the lighter stop {\tilde t_1} could be the next-to-lightest supersymmetric particle (NLSP) in models where the gravitino is the lightest supersymmetric particle (LSP). We do not find any possibility for a stop NLSP in the constrained MSSM with universal input soft supersymmetry-breaking masses at the GUT scale (CMSSM), but do find small allowed regions in models with non-universal Higgs masses (NUHM). We discuss the cosmological evolution of stop hadrons. Most {\tilde t_1}qq `sbaryons' and the corresponding `antisbaryons' annihilate with conventional antibaryons and baryons into {\tilde t_1}{\bar q} `mesinos' and the corresponding `antimesinos', respectively, shortly after the quark-hadron transition in the early Universe, and most mesinos and antimesinos subsequently annihilate. As a result, insufficient metastable charged stop hadrons survive to alter Big Bang nucleosynthesis.
1511.04474
Joshua Eby
Joshua Eby, Chris Kouvaris, Niklas Gr{\o}nlund Nielsen, L.C.R. Wijewardhana
Boson Stars from Self-Interacting Dark Matter
12 pages, 6 figures; references added
null
10.1007/JHEP02(2016)028
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the possibility that self-interacting bosonic dark matter forms star-like objects. We study both the case of attractive and repulsive self-interactions, and we focus particularly in the parameter phase space where self-interactions can solve well standing problems of the collisionless dark matter paradigm. We find the mass radius relations for these dark matter bosonic stars, their density profile as well as the maximum mass they can support.
[ { "created": "Fri, 13 Nov 2015 22:43:08 GMT", "version": "v1" }, { "created": "Fri, 11 Dec 2015 19:31:22 GMT", "version": "v2" } ]
2016-03-23
[ [ "Eby", "Joshua", "" ], [ "Kouvaris", "Chris", "" ], [ "Nielsen", "Niklas Grønlund", "" ], [ "Wijewardhana", "L. C. R.", "" ] ]
We study the possibility that self-interacting bosonic dark matter forms star-like objects. We study both the case of attractive and repulsive self-interactions, and we focus particularly in the parameter phase space where self-interactions can solve well standing problems of the collisionless dark matter paradigm. We find the mass radius relations for these dark matter bosonic stars, their density profile as well as the maximum mass they can support.
hep-ph/0107242
Sannino Francesco
Francesco Sannino (NORDITA)
Color Superconductivity: Symmetries and Effective Lagrangians
6 pages, AIP format. Talk given at QCD@work conference, Martina Franca, Italy, 16-20 Jun 2001
AIP Conf.Proc. 602 (2001) 352-357
10.1063/1.1435946
null
hep-ph
null
I briefly review the symmetries and the associated low energy effective Lagrangian for two light flavor Color Superconductivity (2SC).
[ { "created": "Tue, 24 Jul 2001 00:38:48 GMT", "version": "v1" } ]
2009-11-07
[ [ "Sannino", "Francesco", "", "NORDITA" ] ]
I briefly review the symmetries and the associated low energy effective Lagrangian for two light flavor Color Superconductivity (2SC).
1507.04530
Vladimir Galkin
R. N. Faustov, V. O. Galkin
Strange baryon spectroscopy in the relativistic quark model
21 pages, 3 figures
Phys. Rev. D 92, 054005 (2015)
10.1103/PhysRevD.92.054005
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Mass spectra of strange baryons are calculated in the framework of the relativistic quark model based on the quasipotential approach. Baryons are treated as the relativistic quark-diquark bound systems. It is assumed that two quarks with equal constituent masses form a diquark. The diquark excitations and its internal structure are consistently taken into account. Calculations are performed up to rather high orbital and radial excitations of strange baryons. On this basis the Regge trajectories are constructed. The obtained results are compared with available experimental data and previous predictions. It is found that all masses of the 4- and 3-star, as well as most of the 2- and 1-star states of strange baryons with established quantum numbers are well reproduced. The developed relativistic quark-diquark model predicts less excited states than three-quark models of strange baryons.
[ { "created": "Thu, 16 Jul 2015 11:37:41 GMT", "version": "v1" } ]
2016-10-28
[ [ "Faustov", "R. N.", "" ], [ "Galkin", "V. O.", "" ] ]
Mass spectra of strange baryons are calculated in the framework of the relativistic quark model based on the quasipotential approach. Baryons are treated as the relativistic quark-diquark bound systems. It is assumed that two quarks with equal constituent masses form a diquark. The diquark excitations and its internal structure are consistently taken into account. Calculations are performed up to rather high orbital and radial excitations of strange baryons. On this basis the Regge trajectories are constructed. The obtained results are compared with available experimental data and previous predictions. It is found that all masses of the 4- and 3-star, as well as most of the 2- and 1-star states of strange baryons with established quantum numbers are well reproduced. The developed relativistic quark-diquark model predicts less excited states than three-quark models of strange baryons.
2206.02961
Bao-Xi Sun
Bao-Xi Sun, Ying-Ying Fan and Qin-Qin Cao
The $\phi p$ bound state in the unitary coupled-channel approximation
9 pages, 2 figures and 4 tables. To be published in Communications in Theoretical Physics
Commun. Theor. Phys. 75 (2023) 055301
10.1088/1572-9494/acc31d
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The strong attractive interaction of the $\phi$ meson and the proton is reported by ALICE collaboration recently. The corresponding scattering length $f_0$ is given as $Re(f_0)=0.85\pm0.34(stat)\pm0.14(syst)$fm and $Im(f_0)=0.16\pm0.10(stat)\pm0.09(syst)$fm. The fact that the real part is significant in contrast to the imaginary part indicates a dominate role of the elastic scattering, whereas the inelastic process is less important. In this work, such scattering processes are inspected based on a unitary coupled-channel approach inspired by Bethe-Salpeter equation. The $\phi p$ scattering length is calculated based on this approach, and it is found that the experimental value of the $\phi p$ scattering length can be obtained only if the attractive interaction of the $\phi$ meson and the proton is taken into account. A significant outcome of such attractive interaction is a two-pole structure in the $\phi p$ scattering amplitude. One of the pole, locating at $(1969-i283)$~MeV might correspond to $N(1895)1/2^-$ or $N(1875)3/2^-$ listed in the review of the Particle Data Group(PDG). The other one, locating at ${1949-i3}$~MeV should be a $\phi N$ bound state, which has no counterpart in the PDG data.
[ { "created": "Tue, 7 Jun 2022 01:41:57 GMT", "version": "v1" }, { "created": "Sun, 12 Mar 2023 07:49:33 GMT", "version": "v2" } ]
2023-05-24
[ [ "Sun", "Bao-Xi", "" ], [ "Fan", "Ying-Ying", "" ], [ "Cao", "Qin-Qin", "" ] ]
The strong attractive interaction of the $\phi$ meson and the proton is reported by ALICE collaboration recently. The corresponding scattering length $f_0$ is given as $Re(f_0)=0.85\pm0.34(stat)\pm0.14(syst)$fm and $Im(f_0)=0.16\pm0.10(stat)\pm0.09(syst)$fm. The fact that the real part is significant in contrast to the imaginary part indicates a dominate role of the elastic scattering, whereas the inelastic process is less important. In this work, such scattering processes are inspected based on a unitary coupled-channel approach inspired by Bethe-Salpeter equation. The $\phi p$ scattering length is calculated based on this approach, and it is found that the experimental value of the $\phi p$ scattering length can be obtained only if the attractive interaction of the $\phi$ meson and the proton is taken into account. A significant outcome of such attractive interaction is a two-pole structure in the $\phi p$ scattering amplitude. One of the pole, locating at $(1969-i283)$~MeV might correspond to $N(1895)1/2^-$ or $N(1875)3/2^-$ listed in the review of the Particle Data Group(PDG). The other one, locating at ${1949-i3}$~MeV should be a $\phi N$ bound state, which has no counterpart in the PDG data.
2203.06380
Nicholas Rodd
Kimberly K. Boddy, Mariangela Lisanti, Samuel D. McDermott, Nicholas L. Rodd, Christoph Weniger, Yacine Ali-Ha\"imoud, Malte Buschmann, Ilias Cholis, Djuna Croon, Adrienne L. Erickcek, Vera Gluscevic, Rebecca K. Leane, Siddharth Mishra-Sharma, Julian B. Mu\~noz, Ethan O. Nadler, Priyamvada Natarajan, Adrian Price-Whelan, Simona Vegetti, Samuel J. Witte
Astrophysical and Cosmological Probes of Dark Matter
Contribution to Snowmass 2021, 24 pages, 4 figures, comments welcome
null
null
null
hep-ph astro-ph.CO astro-ph.GA astro-ph.HE
http://creativecommons.org/licenses/by/4.0/
While astrophysical and cosmological probes provide a remarkably precise and consistent picture of the quantity and general properties of dark matter, its fundamental nature remains one of the most significant open questions in physics. Obtaining a more comprehensive understanding of dark matter within the next decade will require overcoming a number of theoretical challenges: the groundwork for these strides is being laid now, yet much remains to be done. Chief among the upcoming challenges is establishing the theoretical foundation needed to harness the full potential of new observables in the astrophysical and cosmological domains, spanning the early Universe to the inner portions of galaxies and the stars therein. Identifying the nature of dark matter will also entail repurposing and implementing a wide range of theoretical techniques from outside the typical toolkit of astrophysics, ranging from effective field theory to the dramatically evolving world of machine learning and artificial-intelligence-based statistical inference. Through this work, the theory frontier will be at the heart of dark matter discoveries in the upcoming decade.
[ { "created": "Sat, 12 Mar 2022 08:58:01 GMT", "version": "v1" } ]
2022-03-15
[ [ "Boddy", "Kimberly K.", "" ], [ "Lisanti", "Mariangela", "" ], [ "McDermott", "Samuel D.", "" ], [ "Rodd", "Nicholas L.", "" ], [ "Weniger", "Christoph", "" ], [ "Ali-Haïmoud", "Yacine", "" ], [ "Buschmann", "M...
While astrophysical and cosmological probes provide a remarkably precise and consistent picture of the quantity and general properties of dark matter, its fundamental nature remains one of the most significant open questions in physics. Obtaining a more comprehensive understanding of dark matter within the next decade will require overcoming a number of theoretical challenges: the groundwork for these strides is being laid now, yet much remains to be done. Chief among the upcoming challenges is establishing the theoretical foundation needed to harness the full potential of new observables in the astrophysical and cosmological domains, spanning the early Universe to the inner portions of galaxies and the stars therein. Identifying the nature of dark matter will also entail repurposing and implementing a wide range of theoretical techniques from outside the typical toolkit of astrophysics, ranging from effective field theory to the dramatically evolving world of machine learning and artificial-intelligence-based statistical inference. Through this work, the theory frontier will be at the heart of dark matter discoveries in the upcoming decade.
hep-ph/0110019
Dubravko Klabucar
Dalibor Kekez (Institute Rudjer Boskovic) and Dubravko Klabucar (Zagreb University)
eta and eta' in a coupled Schwinger-Dyson and Bethe-Salpeter approach. II. The gamma^* gamma transition form factors
Some typos, syntax and the title corrected in accord with the published version
Phys.Rev. D65 (2002) 057901
10.1103/PhysRevD.65.057901
ZTF-01/05
hep-ph nucl-th
null
The applications of the consistently coupled Schwinger-Dyson and Bethe-Salpeter approach to the eta-eta' complex are extended to the two-photon transition form factors of eta and eta' for spacelike transferred momenta. We compare our predictions with experiment and some other theoretical approaches.
[ { "created": "Mon, 1 Oct 2001 15:24:59 GMT", "version": "v1" }, { "created": "Thu, 11 Apr 2002 14:48:46 GMT", "version": "v2" } ]
2009-11-07
[ [ "Kekez", "Dalibor", "", "Institute Rudjer Boskovic" ], [ "Klabucar", "Dubravko", "", "Zagreb University" ] ]
The applications of the consistently coupled Schwinger-Dyson and Bethe-Salpeter approach to the eta-eta' complex are extended to the two-photon transition form factors of eta and eta' for spacelike transferred momenta. We compare our predictions with experiment and some other theoretical approaches.
hep-ph/0404102
Vadim Bednyakov
V.A.Bednyakov (JINR, Dubna) and H.V.Klapdor-Kleingrothaus (MPI-K, Heidelberg)
On dark matter search after DAMA with Ge-73
29 pages, 12 figures, 124 references
Phys.Rev. D70 (2004) 096006
10.1103/PhysRevD.70.096006
null
hep-ph
null
The Weakly Interacting Massive Particle (WIMP) is one of the main candidates for the relic dark matter (DM).In the effective low-energy minimal supersymmetric standard model (effMSSM) the neutralino-nucleon spin and scalar cross sections in the low-mass regime were calculated. The calculated cross sections are compared with almost all experimental currently available exclusion curves for spin-dependent WIMP-proton and WIMP-neutron cross sections. It is demonstrated that in general about two-orders-of-magnitude improvement of the current DM experiment sensitivities is needed to reach the (effMSSM) SUSY predictions. At the current level of accuracy it looks reasonable to safely neglect sub-dominant spin WIMP-nucleon contributions analyzing the data from spin-non-zero targets. To avoid misleading discrepancies between data and SUSY calculations it is, however, preferable to use a mixed spin-scalar coupling approach.This approach is applied to estimate future prospects of experiments with the odd-neutron high-spin isotope Ge-73. It is noticed that the DAMA evidence favors the light Higgs sector in the effMSSM, a high event rate in a Ge-73 detector and relatively high upgoing muon fluxes from relic neutralino annihilations in the Earth and the Sun.
[ { "created": "Mon, 12 Apr 2004 10:18:08 GMT", "version": "v1" } ]
2009-11-10
[ [ "Bednyakov", "V. A.", "", "JINR, Dubna" ], [ "Klapdor-Kleingrothaus", "H. V.", "", "MPI-K,\n Heidelberg" ] ]
The Weakly Interacting Massive Particle (WIMP) is one of the main candidates for the relic dark matter (DM).In the effective low-energy minimal supersymmetric standard model (effMSSM) the neutralino-nucleon spin and scalar cross sections in the low-mass regime were calculated. The calculated cross sections are compared with almost all experimental currently available exclusion curves for spin-dependent WIMP-proton and WIMP-neutron cross sections. It is demonstrated that in general about two-orders-of-magnitude improvement of the current DM experiment sensitivities is needed to reach the (effMSSM) SUSY predictions. At the current level of accuracy it looks reasonable to safely neglect sub-dominant spin WIMP-nucleon contributions analyzing the data from spin-non-zero targets. To avoid misleading discrepancies between data and SUSY calculations it is, however, preferable to use a mixed spin-scalar coupling approach.This approach is applied to estimate future prospects of experiments with the odd-neutron high-spin isotope Ge-73. It is noticed that the DAMA evidence favors the light Higgs sector in the effMSSM, a high event rate in a Ge-73 detector and relatively high upgoing muon fluxes from relic neutralino annihilations in the Earth and the Sun.
hep-ph/0101300
Peter Schweitzer
P. Schweitzer (1), D. Urbano (2), M. V. Polyakov (1 and 3), C. Weiss (4), P. V. Pobylitsa (1 and 3), K. Goeke (1) ((1) Ruhr U., Bochum, (2) Porto U., (3) St. Petersburg, INP, (4) Regensburg U.)
Transversity distributions in the nucleon in the large-N_c limit
45 pages, 16 figures
Phys.Rev.D64:034013,2001
10.1103/PhysRevD.64.034013
RUB-TPII-15/00
hep-ph
null
We compute the quark and antiquark transversity distributions in the nucleon at a low normalization point of 600 MeV in the large-$N_c$ limit, where the nucleon can be described as a soliton of an effective chiral theory (chiral quark-soliton model). The flavor-nonsinglet distributions, $\delta u(x) - \delta d(x)$ and $\delta\bar u(x) - \delta\bar d(x)$, appear in leading order of the $1/N_c$-expansion, while the flavor-singlet distributions, $\delta u(x) + \delta d(x)$ and $\delta\bar u(x) + \delta\bar d(x)$, are non-zero only in next-to-leading order. The transversity quark and antiquark distributions are found to be significantly different from the longitudinally polarized distributions $\Delta u (x) \pm \Delta d (x)$ and $\Delta\bar u (x) \pm \Delta\bar d (x)$, respectively, in contrast to the prediction of the naive non-relativistic quark model. We show that this affects the predictions for the spin asymmetries in Drell-Yan pair production in transversely polarized pp and ppbar collisions.
[ { "created": "Fri, 26 Jan 2001 15:45:33 GMT", "version": "v1" } ]
2014-11-17
[ [ "Schweitzer", "P.", "", "1 and 3" ], [ "Urbano", "D.", "", "1 and 3" ], [ "Polyakov", "M. V.", "", "1 and 3" ], [ "Weiss", "C.", "", "1 and 3" ], [ "Pobylitsa", "P. V.", "", "1 and 3" ], [ "Goeke", "K.", ...
We compute the quark and antiquark transversity distributions in the nucleon at a low normalization point of 600 MeV in the large-$N_c$ limit, where the nucleon can be described as a soliton of an effective chiral theory (chiral quark-soliton model). The flavor-nonsinglet distributions, $\delta u(x) - \delta d(x)$ and $\delta\bar u(x) - \delta\bar d(x)$, appear in leading order of the $1/N_c$-expansion, while the flavor-singlet distributions, $\delta u(x) + \delta d(x)$ and $\delta\bar u(x) + \delta\bar d(x)$, are non-zero only in next-to-leading order. The transversity quark and antiquark distributions are found to be significantly different from the longitudinally polarized distributions $\Delta u (x) \pm \Delta d (x)$ and $\Delta\bar u (x) \pm \Delta\bar d (x)$, respectively, in contrast to the prediction of the naive non-relativistic quark model. We show that this affects the predictions for the spin asymmetries in Drell-Yan pair production in transversely polarized pp and ppbar collisions.
2302.00668
Anish Ghoshal
Anish Ghoshal and Abhishek Naskar
Generalising Axion-like particle as the curvaton: sourcing primordial density perturbation and non-Gaussianities
18 pages (without references), 5 figures. Comments and requests are earnestly welcome
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the non-perturbatively generated axion-like particle (ALP) potential, involving fermions in the dark sector that couple to the ALP, in an early cosmological inflationary stage with the ALP being a spectator field. The potential here deviates from the standard cosine nature due to the presence of the two fermion masses $m_u$ and $m_d$ which couple to the ALP. The ALP is a spectator field during inflation but it starts to oscillate and dominates the energy density of the universe after inflation ends, thereby sourcing isocurvature perturbations, while standard curvature fluctuations form the inflaton are assumed to be sub-dominant. Subsequently the ALP decays converting the isocurvature perturbations to adiabatic perturbations thereby acting as the origin of the primordial density perturbations. We identify the parameter space involving the axion decay constant $f_a$, scale of confinement $\Lambda$, ALP mass $m$ and the masses of the fermions, $m_u$ and $m_d$ where it can satisfactorily behave as the curvaton and source the observed primordial density perturbation. We also predict local non-Gaussianity signals for bi-spectrum and tri-spectrum $f_{NL}$ and $g_{NL}$, as a function of the ratio $m_u/m_d$, which are within the allowed range in the latest Planck observations and are detectable with future observations. Particularly we observed that the value of $f_{NL}$ and $g_{NL}$ are dependent on the ratio of $m_u$ and $m_d$: $f_{NL}$ is more or less positive for all scenarios except $m_u = m_d$ and $g_{NL}$ is always positive irrespective of the ratio between $m_u$ and $m_d$. The results of our analysis in the limit $m_u = m_d$ resembles vanilla curvaton scenario while in the limit $m_u \gg m_d$ resembles pure axion cosine potential.
[ { "created": "Wed, 1 Feb 2023 18:55:34 GMT", "version": "v1" } ]
2023-02-02
[ [ "Ghoshal", "Anish", "" ], [ "Naskar", "Abhishek", "" ] ]
We investigate the non-perturbatively generated axion-like particle (ALP) potential, involving fermions in the dark sector that couple to the ALP, in an early cosmological inflationary stage with the ALP being a spectator field. The potential here deviates from the standard cosine nature due to the presence of the two fermion masses $m_u$ and $m_d$ which couple to the ALP. The ALP is a spectator field during inflation but it starts to oscillate and dominates the energy density of the universe after inflation ends, thereby sourcing isocurvature perturbations, while standard curvature fluctuations form the inflaton are assumed to be sub-dominant. Subsequently the ALP decays converting the isocurvature perturbations to adiabatic perturbations thereby acting as the origin of the primordial density perturbations. We identify the parameter space involving the axion decay constant $f_a$, scale of confinement $\Lambda$, ALP mass $m$ and the masses of the fermions, $m_u$ and $m_d$ where it can satisfactorily behave as the curvaton and source the observed primordial density perturbation. We also predict local non-Gaussianity signals for bi-spectrum and tri-spectrum $f_{NL}$ and $g_{NL}$, as a function of the ratio $m_u/m_d$, which are within the allowed range in the latest Planck observations and are detectable with future observations. Particularly we observed that the value of $f_{NL}$ and $g_{NL}$ are dependent on the ratio of $m_u$ and $m_d$: $f_{NL}$ is more or less positive for all scenarios except $m_u = m_d$ and $g_{NL}$ is always positive irrespective of the ratio between $m_u$ and $m_d$. The results of our analysis in the limit $m_u = m_d$ resembles vanilla curvaton scenario while in the limit $m_u \gg m_d$ resembles pure axion cosine potential.
hep-ph/9307223
Cliff Burgess
C.P. Burgess, Stephen Godfrey, Heinz K\"onig, David London and Ivan Maksymyk
Bounding Anomalous Gauge-Boson Couplings
32 pages
Phys.Rev.D50:7011-7024,1994
10.1103/PhysRevD.50.7011
McGill-93/14, UdeM-LPN-TH-93-154, OCIP/C-93-7
hep-ph
null
In this version we have corrected some minor errors in the tables, corrected typos, and added a reference. We have also updated our comparison with earlier workers. Figures are now included as uuencoded compressed tar files.
[ { "created": "Tue, 6 Jul 1993 03:11:28 GMT", "version": "v1" }, { "created": "Wed, 14 Jul 1993 16:20:56 GMT", "version": "v2" } ]
2010-11-01
[ [ "Burgess", "C. P.", "" ], [ "Godfrey", "Stephen", "" ], [ "König", "Heinz", "" ], [ "London", "David", "" ], [ "Maksymyk", "Ivan", "" ] ]
In this version we have corrected some minor errors in the tables, corrected typos, and added a reference. We have also updated our comparison with earlier workers. Figures are now included as uuencoded compressed tar files.
0903.0455
Ho-Meoyng Choi
Ho-Meoyng Choi (Kyungpook Nat'l Univ.) and Chueng-Ryong Ji (North Carolina State Univ.)
Semileptonic and radiative decays of the B_c meson in light-front quark model
20 pages, 12figures; extensively revised the version including discussion of the light-front zero-mode contribution to the weak form factor
Phys.Rev.D80:054016,2009
10.1103/PhysRevD.80.054016
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate the exclusive semileptonic $B_c\to (D,\eta_c,B,B_s)\ell\nu_\ell$, $\eta_b\to B_c\ell\nu_\ell$($\ell=e,\mu,\tau$) decays using the light-front quark model constrained by the variational principle for the QCD motivated effective Hamiltonian. The form factors $f_+(q^2)$ and $f_-(q^2)$ are obtained from the analytic continuation method in the $q^+=0$ frame. While the form factor $f_+(q^2)$ is free from the zero-mode, the form factor $f_-(q^2)$ is not free from the zero-mode in the $q^+=0$ frame. We quantify the zero-mode contributions to $f_-(q^2)$ for various semileptonic $B_c$ decays. Using our effective method to relate the non-wave function vertex to the light-front valence wave function, we incorporate the zero-mode contribution as a convolution of zero-mode operator with the initial and final state wave functions. Our results are then compared to the available experimental data and the results from other theoretical approaches. Since the prediction on the magnetic dipole $B^*_c\to B_c+\gamma$ decay turns out to be very sensitive to the mass difference between $B^*_c$ and $B_c$ mesons, the decay width $\Gamma(B^*_c \to B_c \gamma)$ may help in determining the mass of $B^*_c$ experimentally. Furthermore, we compare the results from the harmonic oscillator potential and the linear potential and identify the decay processes that are sensitive to the choice of confining potential. From the future experimental data on these sensitive processes, one may obtain more realistic information on the potential between quark and antiquark in the heavy meson system.
[ { "created": "Tue, 3 Mar 2009 08:32:16 GMT", "version": "v1" }, { "created": "Thu, 6 Aug 2009 05:44:20 GMT", "version": "v2" } ]
2009-10-20
[ [ "Choi", "Ho-Meoyng", "", "Kyungpook Nat'l Univ." ], [ "Ji", "Chueng-Ryong", "", "North\n Carolina State Univ." ] ]
We investigate the exclusive semileptonic $B_c\to (D,\eta_c,B,B_s)\ell\nu_\ell$, $\eta_b\to B_c\ell\nu_\ell$($\ell=e,\mu,\tau$) decays using the light-front quark model constrained by the variational principle for the QCD motivated effective Hamiltonian. The form factors $f_+(q^2)$ and $f_-(q^2)$ are obtained from the analytic continuation method in the $q^+=0$ frame. While the form factor $f_+(q^2)$ is free from the zero-mode, the form factor $f_-(q^2)$ is not free from the zero-mode in the $q^+=0$ frame. We quantify the zero-mode contributions to $f_-(q^2)$ for various semileptonic $B_c$ decays. Using our effective method to relate the non-wave function vertex to the light-front valence wave function, we incorporate the zero-mode contribution as a convolution of zero-mode operator with the initial and final state wave functions. Our results are then compared to the available experimental data and the results from other theoretical approaches. Since the prediction on the magnetic dipole $B^*_c\to B_c+\gamma$ decay turns out to be very sensitive to the mass difference between $B^*_c$ and $B_c$ mesons, the decay width $\Gamma(B^*_c \to B_c \gamma)$ may help in determining the mass of $B^*_c$ experimentally. Furthermore, we compare the results from the harmonic oscillator potential and the linear potential and identify the decay processes that are sensitive to the choice of confining potential. From the future experimental data on these sensitive processes, one may obtain more realistic information on the potential between quark and antiquark in the heavy meson system.
hep-ph/0308026
Dmitri Antonov
Dmitri Antonov (Pisa U. & INFN, Pisa)
Heavy-quark condensate at zero- and nonzero temperatures for various forms of the short-distance potential
11 pages, no figures
JHEP 0310:030,2003
10.1088/1126-6708/2003/10/030
IFUP-TH 2003/25
hep-ph hep-lat
null
With the use of the world-line formalism, the heavy-quark condensate in the SU(N)-QCD is evaluated for the cases when the next-to-1/r term in the quark-antiquark potential at short distances is either quadratic, or linear. In the former case, the standard QCD-sum-rules result is reproduced, while the latter result is a novel one. Explicitly, it is UV-finite only in less than four dimensions. This fact excludes a possibility to have, in four dimensions, very short strings (whose length has the scale of the lattice spacing), and consequently the short-range linear potential (if it exists) cannot violate the OPE. In any number of dimensions, the obtained novel expression for the quark condensate depends on the string tension at short distances, rather than on the gluon condensate, and grows linearly with the number of colors in the same way as the standard QCD-sum-rules expression. The use of the world-line formalism enables one to generalize further both results to the case of finite temperatures. A generalization of the QCD-sum-rules expression to the case of an arbitrary number of space-time dimensions is also obtained and is shown to be UV-finite, provided this number is smaller than six.
[ { "created": "Mon, 4 Aug 2003 15:49:36 GMT", "version": "v1" } ]
2010-02-23
[ [ "Antonov", "Dmitri", "", "Pisa U. & INFN, Pisa" ] ]
With the use of the world-line formalism, the heavy-quark condensate in the SU(N)-QCD is evaluated for the cases when the next-to-1/r term in the quark-antiquark potential at short distances is either quadratic, or linear. In the former case, the standard QCD-sum-rules result is reproduced, while the latter result is a novel one. Explicitly, it is UV-finite only in less than four dimensions. This fact excludes a possibility to have, in four dimensions, very short strings (whose length has the scale of the lattice spacing), and consequently the short-range linear potential (if it exists) cannot violate the OPE. In any number of dimensions, the obtained novel expression for the quark condensate depends on the string tension at short distances, rather than on the gluon condensate, and grows linearly with the number of colors in the same way as the standard QCD-sum-rules expression. The use of the world-line formalism enables one to generalize further both results to the case of finite temperatures. A generalization of the QCD-sum-rules expression to the case of an arbitrary number of space-time dimensions is also obtained and is shown to be UV-finite, provided this number is smaller than six.
hep-ph/9702371
Frank Wilczek
Frank Wilczek
The Future of Particle Physics as a Natural Science
Corrected Reference 1. LaTeX, 25 Pages, 6 figures
Int.J.Mod.Phys.A13:863-886,1998
10.1142/S0217751X9800038X
IASSNS-HEP 97-11
hep-ph hep-th
null
In the first part of the talk, I give a low-resolution overview of the current state of particle physics - the triumph of the Standard Model and its discontents. I review and re-endorse the remarkably direct and (to me) compelling argument that existing data, properly interpreted, point toward a unified theory of fundamental particle interactions and toward low-energy supersymmetry as the near-term future of high energy physics as a natural science. I then attempt, as requested, some more `visionary' - i.e. even lower resolution - comments about the farther future. In that spirit, I emphasize the continuing importance of condensed matter physics as a source of inspiration and potential application, in particular for expansion of symmetry concepts, and of cosmology as a source of problems, applications, and perhaps ultimately limitations.
[ { "created": "Wed, 19 Feb 1997 19:19:58 GMT", "version": "v1" }, { "created": "Thu, 20 Feb 1997 14:57:25 GMT", "version": "v2" } ]
2011-04-20
[ [ "Wilczek", "Frank", "" ] ]
In the first part of the talk, I give a low-resolution overview of the current state of particle physics - the triumph of the Standard Model and its discontents. I review and re-endorse the remarkably direct and (to me) compelling argument that existing data, properly interpreted, point toward a unified theory of fundamental particle interactions and toward low-energy supersymmetry as the near-term future of high energy physics as a natural science. I then attempt, as requested, some more `visionary' - i.e. even lower resolution - comments about the farther future. In that spirit, I emphasize the continuing importance of condensed matter physics as a source of inspiration and potential application, in particular for expansion of symmetry concepts, and of cosmology as a source of problems, applications, and perhaps ultimately limitations.
0804.2111
Andre Rubbia
A.Badertscher, T.Hasegawa, T.Kobayashi, A.Marchionni, A.Meregaglia, T.Maruyama, K.Nishikawa, A.Rubbia
A Possible Future Long Baseline Neutrino and Nucleon Decay Experiment with a 100 kton Liquid Argon TPC at Okinoshima using the J-PARC Neutrino Facility
26 pages, 15 figures, Based on invited talks at 4th International Workshop on Nuclear and Particle Physics at J-PARC (NP08)
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we consider the physics performance of a single far detector composed of a 100 kton next generation Liquid Argon Time Projection Chamber (LAr TPC) possibly located at shallow depth, coupled to the J-PARC neutrino beam facility with a realistic 1.66 MW operation of the Main Ring. The new far detector could be located in the region of Okinoshima islands (baseline $L\sim 658$ km). Our emphasis is based on the measurement of the $\theta_{13}$ and $\delta_{CP}$ parameters, possibly following indications for a non-vanishing $\theta_{13}$ in T2K, and relies on the opportunity offered by the LAr TPC to reconstruct the incoming neutrino energy with high precision compared to other large detector technologies. We mention other possible baselines like for example J-PARC-Kamioka (baseline $L\sim 295$ km), or J-PARC-Eastern Korean coast (baseline $L\sim 1025$ km). Such a detector would also further explore the existence of proton decays.
[ { "created": "Mon, 14 Apr 2008 08:52:04 GMT", "version": "v1" } ]
2008-04-15
[ [ "Badertscher", "A.", "" ], [ "Hasegawa", "T.", "" ], [ "Kobayashi", "T.", "" ], [ "Marchionni", "A.", "" ], [ "Meregaglia", "A.", "" ], [ "Maruyama", "T.", "" ], [ "Nishikawa", "K.", "" ], [ "Rubbia...
In this paper, we consider the physics performance of a single far detector composed of a 100 kton next generation Liquid Argon Time Projection Chamber (LAr TPC) possibly located at shallow depth, coupled to the J-PARC neutrino beam facility with a realistic 1.66 MW operation of the Main Ring. The new far detector could be located in the region of Okinoshima islands (baseline $L\sim 658$ km). Our emphasis is based on the measurement of the $\theta_{13}$ and $\delta_{CP}$ parameters, possibly following indications for a non-vanishing $\theta_{13}$ in T2K, and relies on the opportunity offered by the LAr TPC to reconstruct the incoming neutrino energy with high precision compared to other large detector technologies. We mention other possible baselines like for example J-PARC-Kamioka (baseline $L\sim 295$ km), or J-PARC-Eastern Korean coast (baseline $L\sim 1025$ km). Such a detector would also further explore the existence of proton decays.
1501.04379
Zhun Lu
Zhun Lu and Ivan Schmidt
Twist-3 fragmentation functions in a spectator model with gluon rescattering
typo corrected, version published in PLB
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the twist-3 fragmentation functions $H$ and $\tilde{H}$, by applying a spectator model. In the calculation we consider the effect of the gluon rescattering at one loop level. We find that in this case the hard-vertex diagram, which gives zero contribution to the Collins function, does contribute to the fragmentation function $H$. The calculation shows that the twist-3 T-odd fragmentation functions are free of light-cone divergences. The parameters of the model are fitted from the known parametrization of the unpolarized fragmentation $D_1$ and the Collins function $H_1^\perp$. We find our result for the favored fragmentation function is consistent with the recent extraction on $H$ and $\tilde{H}$ from pp data. We also check numerically the equation of motion relation for $H$, $\tilde{H}$ and find that relation holds fairly well in the spectator model.
[ { "created": "Mon, 19 Jan 2015 03:47:37 GMT", "version": "v1" }, { "created": "Thu, 14 Jan 2016 16:12:10 GMT", "version": "v2" } ]
2016-01-15
[ [ "Lu", "Zhun", "" ], [ "Schmidt", "Ivan", "" ] ]
We study the twist-3 fragmentation functions $H$ and $\tilde{H}$, by applying a spectator model. In the calculation we consider the effect of the gluon rescattering at one loop level. We find that in this case the hard-vertex diagram, which gives zero contribution to the Collins function, does contribute to the fragmentation function $H$. The calculation shows that the twist-3 T-odd fragmentation functions are free of light-cone divergences. The parameters of the model are fitted from the known parametrization of the unpolarized fragmentation $D_1$ and the Collins function $H_1^\perp$. We find our result for the favored fragmentation function is consistent with the recent extraction on $H$ and $\tilde{H}$ from pp data. We also check numerically the equation of motion relation for $H$, $\tilde{H}$ and find that relation holds fairly well in the spectator model.
2003.12053
Kimberley Keri Vos
Thomas Mannel, Kevin Olschewsky and K. Keri Vos
CP Violation in Three-body $B$ Decays: A Model Ansatz
TUM-HEP-1259/20, SI-HEP-2020-06
null
10.1007/JHEP06(2020)073
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The mechanism of CP violation remains one of the puzzles in particle physics. Key to understanding this phenomenon are nonleptonic $B$ decays, especially multibody decays which exhibit large CP asymmetries in various regions of phase space. A full QCD-based theoretical description of these decays is still missing, requiring the use of models to fit the data. In this paper, we suggest a model ansatz which reflects the underlying physics and the known mechanism of CP violation via the CKM matrix. In addition, since CP violation is driven by the interference between amplitudes with and without valence charm quarks, we argue that the opening of the open-charm threshold may play an important role in generating CP violation in the high invariant mass region. We present a natural extension of the isobar model to incorporate these effects. We suggest an analysis of nonleptonic three-body $B$ decay data including this extension, which would be interesting as it may give new hints to the sources of CP violation both at low and high invariant mass.
[ { "created": "Thu, 26 Mar 2020 17:44:36 GMT", "version": "v1" } ]
2020-07-15
[ [ "Mannel", "Thomas", "" ], [ "Olschewsky", "Kevin", "" ], [ "Vos", "K. Keri", "" ] ]
The mechanism of CP violation remains one of the puzzles in particle physics. Key to understanding this phenomenon are nonleptonic $B$ decays, especially multibody decays which exhibit large CP asymmetries in various regions of phase space. A full QCD-based theoretical description of these decays is still missing, requiring the use of models to fit the data. In this paper, we suggest a model ansatz which reflects the underlying physics and the known mechanism of CP violation via the CKM matrix. In addition, since CP violation is driven by the interference between amplitudes with and without valence charm quarks, we argue that the opening of the open-charm threshold may play an important role in generating CP violation in the high invariant mass region. We present a natural extension of the isobar model to incorporate these effects. We suggest an analysis of nonleptonic three-body $B$ decay data including this extension, which would be interesting as it may give new hints to the sources of CP violation both at low and high invariant mass.
2002.01239
Mar\'ia Teresa N\'u\~nez Pardo De Vera
Mar\'ia Teresa N\'u\~nez Pardo de Vera, Mikael Berggren, Jenny List
Chargino production at the ILC
Talk presented at the International Workshop on Future Linear Colliders (LCWS2019), Sendai, Japan, 28 October-1 November, 2019. C19-10-28
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The lighter chargino, $\widetilde{\chi}_1^{\pm}$, is a prime candidate to be the next-to-lightest SUSY particle (the NLSP). Several analyses of $\widetilde{\chi}_1^{\pm}$ pair-production at the ILC, at specific model-points, have been performed, showing that detection and property-determination is possible, even for very difficult cases. However, no recent studies have evaluated the reach of the ILC to detect $\widetilde{\chi}_1^{\pm}$ pair production in general. In this study, cross sections for $\widetilde{\chi}_1^{\pm}$ pair production at the ILC were evaluated within a wide range of parameters. The aim was to determine the conditions for the lowest cross sections and compare these worst-case values with an estimation of the cross section limit for the observation of the lightest charginos at the ILC. The estimated limits were extrapolated from the studies performed at LEP, which can also be regarded as a worst-case scenario, since the tremendous advances in detector and accelerator technologies are disregarded
[ { "created": "Tue, 4 Feb 2020 11:54:58 GMT", "version": "v1" } ]
2020-02-05
[ [ "de Vera", "María Teresa Núñez Pardo", "" ], [ "Berggren", "Mikael", "" ], [ "List", "Jenny", "" ] ]
The lighter chargino, $\widetilde{\chi}_1^{\pm}$, is a prime candidate to be the next-to-lightest SUSY particle (the NLSP). Several analyses of $\widetilde{\chi}_1^{\pm}$ pair-production at the ILC, at specific model-points, have been performed, showing that detection and property-determination is possible, even for very difficult cases. However, no recent studies have evaluated the reach of the ILC to detect $\widetilde{\chi}_1^{\pm}$ pair production in general. In this study, cross sections for $\widetilde{\chi}_1^{\pm}$ pair production at the ILC were evaluated within a wide range of parameters. The aim was to determine the conditions for the lowest cross sections and compare these worst-case values with an estimation of the cross section limit for the observation of the lightest charginos at the ILC. The estimated limits were extrapolated from the studies performed at LEP, which can also be regarded as a worst-case scenario, since the tremendous advances in detector and accelerator technologies are disregarded
1103.5930
Christoph Luhn
Stefan Antusch, Stephen F. King, Christoph Luhn, Martin Spinrath
Right unitarity triangles and tri-bimaximal mixing from discrete symmetries and unification
29 pages, 4 figures, version to be published in NPB
null
10.1016/j.nuclphysb.2011.05.005
MPP-2011-38, SHEP-11-04, SISSA 15/2011/EP
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose new classes of models which predict both tri-bimaximal lepton mixing and a right-angled Cabibbo-Kobayashi-Maskawa (CKM) unitarity triangle, alpha approximately 90 degrees. The ingredients of the models include a supersymmetric (SUSY) unified gauge group such as SU(5), a discrete family symmetry such as A4 or S4, a shaping symmetry including products of Z2 and Z4 groups as well as spontaneous CP violation. We show how the vacuum alignment in such models allows a simple explanation of alpha approximately 90 degrees by a combination of purely real or purely imaginary vacuum expectation values (vevs) of the flavons responsible for family symmetry breaking. This leads to quark mass matrices with 1-3 texture zeros that satisfy the phase sum rule and lepton mass matrices that satisfy the lepton mixing sum rule together with a new prediction that the leptonic CP violating oscillation phase is close to either 0, 90, 180, or 270 degrees depending on the model, with neutrino masses being purely real (no complex Majorana phases). This leads to the possibility of having right-angled unitarity triangles in both the quark and lepton sectors.
[ { "created": "Wed, 30 Mar 2011 13:54:48 GMT", "version": "v1" }, { "created": "Sun, 15 May 2011 15:55:38 GMT", "version": "v2" } ]
2015-05-27
[ [ "Antusch", "Stefan", "" ], [ "King", "Stephen F.", "" ], [ "Luhn", "Christoph", "" ], [ "Spinrath", "Martin", "" ] ]
We propose new classes of models which predict both tri-bimaximal lepton mixing and a right-angled Cabibbo-Kobayashi-Maskawa (CKM) unitarity triangle, alpha approximately 90 degrees. The ingredients of the models include a supersymmetric (SUSY) unified gauge group such as SU(5), a discrete family symmetry such as A4 or S4, a shaping symmetry including products of Z2 and Z4 groups as well as spontaneous CP violation. We show how the vacuum alignment in such models allows a simple explanation of alpha approximately 90 degrees by a combination of purely real or purely imaginary vacuum expectation values (vevs) of the flavons responsible for family symmetry breaking. This leads to quark mass matrices with 1-3 texture zeros that satisfy the phase sum rule and lepton mass matrices that satisfy the lepton mixing sum rule together with a new prediction that the leptonic CP violating oscillation phase is close to either 0, 90, 180, or 270 degrees depending on the model, with neutrino masses being purely real (no complex Majorana phases). This leads to the possibility of having right-angled unitarity triangles in both the quark and lepton sectors.
hep-ph/0308095
Kwei-Chou Yang
Kwei-Chou Yang
Higher Twist Effects in Hadronic B Decays
9 pages, 6 figures, presented at the Czech-Taiwanese Workshop on Intermediate- and High-Energy Physics, March 3-5, 2003 (to appear in Czech J. Phys)
Czech.J.Phys. 53 (2003) 707-715
10.1023/A:1025367614678
null
hep-ph
null
Within the framework of QCD factorization, we discuss various important corrections arising from higher twist distribution amplitudes of mesons in the hadronic B decays.
[ { "created": "Fri, 8 Aug 2003 09:05:11 GMT", "version": "v1" } ]
2009-11-10
[ [ "Yang", "Kwei-Chou", "" ] ]
Within the framework of QCD factorization, we discuss various important corrections arising from higher twist distribution amplitudes of mesons in the hadronic B decays.
1405.1095
Adam Falkowski
Adam Falkowski and Roberto Vega-Morales
Exotic Higgs decays in the golden channel
16 pages; v2: minor corrections, references added
null
10.1007/JHEP12(2014)037
LPT Orsay 14-23
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Higgs boson may have decay channels that are not predicted by the Standard Model. We discuss the prospects of probing exotic Higgs decays at the LHC using the 4-lepton final state. We study two specific scenarios, with new particles appearing in the intermediate state of the 4-lepton Higgs decay. In one, Higgs decays to a Z boson and a new massive gauge boson, the so-called hidden photon. In the other, Higgs decays to an electron or a muon and a new vector-like fermion. We argue that the upcoming LHC run will be able to explore a new parameter space of these models that is allowed by current precision constraints. Employing matrix element methods, we use the full information contained in the differential distribution of the 4-lepton final state to extract the signal of exotic decays. We find that, in some cases, the LHC can be sensitive to new physics even when the correction to the total 4-lepton Higgs rate is of the order of a percent. In particular, for the simplest realization of the hidden photon with the mass between 15 and 65 GeV, new parameter space can be explored in the LHC run-II.
[ { "created": "Mon, 5 May 2014 22:13:55 GMT", "version": "v1" }, { "created": "Tue, 27 May 2014 19:31:27 GMT", "version": "v2" } ]
2015-06-19
[ [ "Falkowski", "Adam", "" ], [ "Vega-Morales", "Roberto", "" ] ]
The Higgs boson may have decay channels that are not predicted by the Standard Model. We discuss the prospects of probing exotic Higgs decays at the LHC using the 4-lepton final state. We study two specific scenarios, with new particles appearing in the intermediate state of the 4-lepton Higgs decay. In one, Higgs decays to a Z boson and a new massive gauge boson, the so-called hidden photon. In the other, Higgs decays to an electron or a muon and a new vector-like fermion. We argue that the upcoming LHC run will be able to explore a new parameter space of these models that is allowed by current precision constraints. Employing matrix element methods, we use the full information contained in the differential distribution of the 4-lepton final state to extract the signal of exotic decays. We find that, in some cases, the LHC can be sensitive to new physics even when the correction to the total 4-lepton Higgs rate is of the order of a percent. In particular, for the simplest realization of the hidden photon with the mass between 15 and 65 GeV, new parameter space can be explored in the LHC run-II.