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1501.01938
Gilberto Tetlalmatzi-Xolocotzi
Gilberto Tetlalmatzi-Xolocotzi
New physics in $\Delta \Gamma_d$
Proceedings of the workshop "Flavorful Ways to New Physics", October 28-31 2014, Freudenstadt, Germany
null
null
IPPP/15/02 DCPT/15/04
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the possibility of having new physics effects in the decay rate difference, $\Delta \Gamma_d$, of neutral $B_d$ mesons. Three different sources of enhancement are considered, CKM unitarity violations, beyond standard model effects in the tree-level dimension six operators $(\bar{d}p)(\bar{p}'b)$ with $p,p'=u,c$; and large enhancements of the almost unconstrained operators $(\bar{d}b)(\bar{\tau}\tau)$. We find that deviations of several hundred per cent from the standard model prediction of $\Delta \Gamma_d$ are not excluded by current experimental data.
[ { "created": "Thu, 8 Jan 2015 19:47:36 GMT", "version": "v1" } ]
2015-01-09
[ [ "Tetlalmatzi-Xolocotzi", "Gilberto", "" ] ]
We analyze the possibility of having new physics effects in the decay rate difference, $\Delta \Gamma_d$, of neutral $B_d$ mesons. Three different sources of enhancement are considered, CKM unitarity violations, beyond standard model effects in the tree-level dimension six operators $(\bar{d}p)(\bar{p}'b)$ with $p,p'=u,c$; and large enhancements of the almost unconstrained operators $(\bar{d}b)(\bar{\tau}\tau)$. We find that deviations of several hundred per cent from the standard model prediction of $\Delta \Gamma_d$ are not excluded by current experimental data.
1910.14586
Digesh Raut
Nobuchika Okada, Digesh Raut, and Qaisar Shafi
Inflection-Point Inflation with Axion Dark Matter in light of Trans-Planckian Censorship Conjecture
6 pages, 2 figures, revised Section V
null
10.1016/j.physletb.2020.136001
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the recently proposed Trans-Planckian Censorship Conjecture (TCC), we propose a gauged $B-L$ model of inflection-point inflation with axion dark matter. The Hubble scale during inflation ($H_{\rm inf}$) satisfies the TCC bound of $H_{\rm inf} \lesssim 1$ GeV, the axion dark matter scenario is free from the axion domain wall and isocurvature problems, and the axion decay constant can be larger than $10^{12}$ GeV. The seesaw mechanism is automatically incorporated in the model and the observed baryon asymmetry of the universe can be reproduced via resonant leptogenesis.
[ { "created": "Thu, 31 Oct 2019 16:40:36 GMT", "version": "v1" }, { "created": "Wed, 6 Nov 2019 15:00:08 GMT", "version": "v2" }, { "created": "Wed, 3 Jun 2020 12:31:03 GMT", "version": "v3" } ]
2020-12-09
[ [ "Okada", "Nobuchika", "" ], [ "Raut", "Digesh", "" ], [ "Shafi", "Qaisar", "" ] ]
Motivated by the recently proposed Trans-Planckian Censorship Conjecture (TCC), we propose a gauged $B-L$ model of inflection-point inflation with axion dark matter. The Hubble scale during inflation ($H_{\rm inf}$) satisfies the TCC bound of $H_{\rm inf} \lesssim 1$ GeV, the axion dark matter scenario is free from the axion domain wall and isocurvature problems, and the axion decay constant can be larger than $10^{12}$ GeV. The seesaw mechanism is automatically incorporated in the model and the observed baryon asymmetry of the universe can be reproduced via resonant leptogenesis.
1906.08035
Marta Moscati
Marta Moscati
New Physics in $b\to c \tau \nu$: Impact of Polarisation Observables and $B_c\to\tau\nu$
8 pages, 4 figures, Proceedings for FPCP 2019, 6-10 May 2019, Victoria BC Canada. v2: references added
null
null
TTP19-015
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The experimental values of the lepton-flavour-universality tests ${\cal R}(D)$ and ${\cal R}(D^*)$ show a tension of about $3.1\sigma$ with their Standard Model prediction. Motivated by this tension, we perform a fit of the $b\to c\tau\nu$ data. We consider one-particle scenarios imposing consecutive limits on $\text{BR}(B_c\to \tau\nu_\tau)$, and analyse how these limits affect the fits. We include the polarisation observables available to date and predict those that are still to be measured, and conclude that they have a high model-resolving power. For each scenario we also predict ${\cal R}(\Lambda_c)$, observing that an enhancement of ${\cal R}(D^{(*)})$ implies an enhancement of ${\cal R}(\Lambda_c)$ in any scenario. We trace back this enhancement to a sum-rule valid irrespective of the scenario used to fit ${\cal R}(D^{(*)})$.
[ { "created": "Wed, 19 Jun 2019 12:10:31 GMT", "version": "v1" }, { "created": "Tue, 9 Jul 2019 05:16:35 GMT", "version": "v2" } ]
2019-07-10
[ [ "Moscati", "Marta", "" ] ]
The experimental values of the lepton-flavour-universality tests ${\cal R}(D)$ and ${\cal R}(D^*)$ show a tension of about $3.1\sigma$ with their Standard Model prediction. Motivated by this tension, we perform a fit of the $b\to c\tau\nu$ data. We consider one-particle scenarios imposing consecutive limits on $\text{BR}(B_c\to \tau\nu_\tau)$, and analyse how these limits affect the fits. We include the polarisation observables available to date and predict those that are still to be measured, and conclude that they have a high model-resolving power. For each scenario we also predict ${\cal R}(\Lambda_c)$, observing that an enhancement of ${\cal R}(D^{(*)})$ implies an enhancement of ${\cal R}(\Lambda_c)$ in any scenario. We trace back this enhancement to a sum-rule valid irrespective of the scenario used to fit ${\cal R}(D^{(*)})$.
hep-ph/9302310
Rajesh Ramchand Parwani
Rajesh R. Parwani
Dimensionality of spacetime as a gauge-invariance parameter in Yang-Mills calculations
Latex, 23 pages; preprint number SPhT/93-004 (Revised)
Phys.Rev. D48 (1993) 3852-3859
10.1103/PhysRevD.48.3852
null
hep-ph
null
This is the revised version of an earlier paper with the same title.
[ { "created": "Thu, 25 Feb 1993 17:15:37 GMT", "version": "v1" }, { "created": "Thu, 12 Aug 1993 19:29:10 GMT", "version": "v2" } ]
2009-10-22
[ [ "Parwani", "Rajesh R.", "" ] ]
This is the revised version of an earlier paper with the same title.
hep-ph/0203094
Sergej Slabospitsky
S.R. Slabospitsky (IHEP, Protvino, Russia)
Study of s-channel Charged Higgs Production in CMS
15 pages, Latex, 12 figures, minor changes
null
null
CMS NOTE 2002/010
hep-ph
null
CMS potential for study of the s-channel $H^{\pm}$-boson production via light quark annihilation is investigated for large values of $\tan\beta$ ($=20\div 50$) and relatively light charge Higgs boson ($M_H = 200 \div 400$ GeV). An appropriate parameterisation for $M_{\top}(j, \ETM)$-distributions of the signal and background events is proposed, which provides the determination of the charged Higgs mass and $\tan\beta$ parameter.
[ { "created": "Sat, 9 Mar 2002 12:18:00 GMT", "version": "v1" }, { "created": "Wed, 13 Mar 2002 17:10:44 GMT", "version": "v2" }, { "created": "Tue, 19 Mar 2002 10:21:42 GMT", "version": "v3" } ]
2007-05-23
[ [ "Slabospitsky", "S. R.", "", "IHEP, Protvino, Russia" ] ]
CMS potential for study of the s-channel $H^{\pm}$-boson production via light quark annihilation is investigated for large values of $\tan\beta$ ($=20\div 50$) and relatively light charge Higgs boson ($M_H = 200 \div 400$ GeV). An appropriate parameterisation for $M_{\top}(j, \ETM)$-distributions of the signal and background events is proposed, which provides the determination of the charged Higgs mass and $\tan\beta$ parameter.
2102.01554
Celio Adrega de Moura Jr
Omar G. Miranda, Guadalupe Moreno-Granados, Celio A. Moura
Sensitivity of accelerator-based neutrino experiments to neutrino-electron scattering radiative corrections
23 pages, 8 figures, new references added, version accepted for publication
Phys. Rev. D 104, 013007 (2021)
10.1103/PhysRevD.104.013007
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Future long-baseline neutrino experiments will measure neutrino oscillation properties with unprecedented precision and will search for clear signatures of CP violation in the leptonic sector. Near detectors can measure the neutrino-electron scattering with high statistics, giving the chance for its precise measurement. We study, in this work, the expectations for the measurement of radiative corrections in this process. We focus on the determination of contributions that are exclusive to the neutrino channels, particularly on the neutrino charge radius. We illustrate how the perspectives in a first clear measurement of this effective quantity are encouraging.
[ { "created": "Tue, 2 Feb 2021 15:27:30 GMT", "version": "v1" }, { "created": "Fri, 30 Jul 2021 19:21:12 GMT", "version": "v2" } ]
2021-08-03
[ [ "Miranda", "Omar G.", "" ], [ "Moreno-Granados", "Guadalupe", "" ], [ "Moura", "Celio A.", "" ] ]
Future long-baseline neutrino experiments will measure neutrino oscillation properties with unprecedented precision and will search for clear signatures of CP violation in the leptonic sector. Near detectors can measure the neutrino-electron scattering with high statistics, giving the chance for its precise measurement. We study, in this work, the expectations for the measurement of radiative corrections in this process. We focus on the determination of contributions that are exclusive to the neutrino channels, particularly on the neutrino charge radius. We illustrate how the perspectives in a first clear measurement of this effective quantity are encouraging.
hep-ph/0108191
Carlo Giunti
M.V. Garzelli, C. Giunti
Bayesian View Of Solar Neutrino Oscillations
31 pages, 8 figures. Final version to be published in JHEP
JHEP 0112:017,2001
10.1088/1126-6708/2001/12/017
null
hep-ph astro-ph hep-ex physics.data-an
null
We present the results of a Bayesian analysis of solar neutrino data in terms of nu_e->nu_{mu,tau} and nu_e->nu_s oscillations, where nu_s is a sterile neutrino. We perform a Rates Analysis of the rates of solar neutrino experiments, including the first SNO CC result, and spectral data of the CHOOZ experiment, and a Global Analysis that takes into account also the Super-Kamiokande day and night electron energy spectra. We show that the Bayesian analysis does not suffer any problem from the inclusion of the numerous bins of the CHOOZ and Super-Kamiokande energy spectra and allows to reach the same conclusions on the favored type of neutrino transitions and on the determination of the most favored values of the oscillation parameters in both the Rates and Global Analysis. Our Bayesian analysis shows that nu_e->nu_s transitions are strongly disfavored with respect to nu_e->nu_{mu,tau} transitions. In the case of nu_e->nu_{mu,tau} oscillations, the LMA region is favored by the data (86% probability), the LOW region has some small chance (13% probability), the VO region is almost excluded (1% probability) and the SMA region is practically excluded (0.01% probability). We calculate also the marginal posterior probability distributions for tan^2 theta and Delta m^2 and we show that the data imply large mixing almost with certainty and large values of Delta m^2 are favored. We present also the results of a standard least-squares analysis and we show that the standard goodness of fit test is not able to rejects pure nu_e->nu_s transitions. The likelihood ratio test allows to reject pure nu_e->nu_s transitions in favor of nu_e->nu_{mu,tau} transitions only in the Global Analysis.
[ { "created": "Thu, 23 Aug 2001 12:56:00 GMT", "version": "v1" }, { "created": "Mon, 17 Sep 2001 16:46:24 GMT", "version": "v2" }, { "created": "Tue, 18 Dec 2001 14:12:18 GMT", "version": "v3" } ]
2015-06-25
[ [ "Garzelli", "M. V.", "" ], [ "Giunti", "C.", "" ] ]
We present the results of a Bayesian analysis of solar neutrino data in terms of nu_e->nu_{mu,tau} and nu_e->nu_s oscillations, where nu_s is a sterile neutrino. We perform a Rates Analysis of the rates of solar neutrino experiments, including the first SNO CC result, and spectral data of the CHOOZ experiment, and a Global Analysis that takes into account also the Super-Kamiokande day and night electron energy spectra. We show that the Bayesian analysis does not suffer any problem from the inclusion of the numerous bins of the CHOOZ and Super-Kamiokande energy spectra and allows to reach the same conclusions on the favored type of neutrino transitions and on the determination of the most favored values of the oscillation parameters in both the Rates and Global Analysis. Our Bayesian analysis shows that nu_e->nu_s transitions are strongly disfavored with respect to nu_e->nu_{mu,tau} transitions. In the case of nu_e->nu_{mu,tau} oscillations, the LMA region is favored by the data (86% probability), the LOW region has some small chance (13% probability), the VO region is almost excluded (1% probability) and the SMA region is practically excluded (0.01% probability). We calculate also the marginal posterior probability distributions for tan^2 theta and Delta m^2 and we show that the data imply large mixing almost with certainty and large values of Delta m^2 are favored. We present also the results of a standard least-squares analysis and we show that the standard goodness of fit test is not able to rejects pure nu_e->nu_s transitions. The likelihood ratio test allows to reject pure nu_e->nu_s transitions in favor of nu_e->nu_{mu,tau} transitions only in the Global Analysis.
hep-ph/9603335
Robert Mann
J.R. Mureika and R.B. Mann
Three Flavour Gravitationally Induced Neutrino Oscillations and the Solar Neutrino Problem
50 pages, 3 macros (included), 22 figures
Phys.Rev. D54 (1996) 2761-2778
10.1103/PhysRevD.54.2761
WATPHYS TH-96/02
hep-ph gr-qc
null
Some implications of the proposal that flavor nondiagonal couplings of neutrinos to gravity might resolve the solar neutrino problem are considered in the context of three neutrino flavors. The two--flavor model is discussed as a limiting case of the full three-generation mechanism, and the behavior of the $\nue$ survival probability for various values of the three--flavor parameters is studied. Overlapping allowed SNU regions are obtained for the neutrinos which most likely contribute to the observed solar neutrino deficiency, and the effects of the addition of a third flavor are discussed. The extension to a three--generation framework is found to yield a greater allowed region of parameter space, suggesting that gravitationally--induced neutrino oscillations remain a viable explanation of the Solar Neutrino Problem.
[ { "created": "Mon, 18 Mar 1996 19:29:03 GMT", "version": "v1" } ]
2009-10-28
[ [ "Mureika", "J. R.", "" ], [ "Mann", "R. B.", "" ] ]
Some implications of the proposal that flavor nondiagonal couplings of neutrinos to gravity might resolve the solar neutrino problem are considered in the context of three neutrino flavors. The two--flavor model is discussed as a limiting case of the full three-generation mechanism, and the behavior of the $\nue$ survival probability for various values of the three--flavor parameters is studied. Overlapping allowed SNU regions are obtained for the neutrinos which most likely contribute to the observed solar neutrino deficiency, and the effects of the addition of a third flavor are discussed. The extension to a three--generation framework is found to yield a greater allowed region of parameter space, suggesting that gravitationally--induced neutrino oscillations remain a viable explanation of the Solar Neutrino Problem.
2105.08745
Thomas Flacke
Aldo Deandrea, Thomas Flacke, Benjamin Fuks, Luca Panizzi and Hua-Sheng Shao
Single production of vector-like quarks: the effects of large width, interference and NLO corrections
55 pages, 27 figures, v3:typo in normalization factors Eq.(3.13) fixed, Fig. 4 replaced
JHEP 08 (2021) 107; JHEP 11 (2022) 028 (erratum)
10.1007/JHEP08(2021)107; 10.1007/JHEP11(2022)028
CTPU-PTC-21-18
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We provide a comprehensive discussion, together with a complete setup for simulations, relevant for the production of a single vector-like quark at hadron colliders. Our predictions include finite width effects, signal-background interference effects and next-to-leading order QCD corrections. We explicitly apply the framework to study the single production of a vector-like quark $T$ with charge 2/3, but the same procedure can be used to analyse the single production of vector-like quarks with charge $-4/3$, $-1/3$, $2/3$ and $5/3$, when the vector-like quark interacts with the Standard Model quarks and electroweak bosons. Moreover, this procedure can be straightforwardly extended to include additional interactions with exotic particles. We provide quantitative results for representative benchmark scenarios characterised by the $T$ mass and width, and we determine the role of the interference terms for a range of masses and widths of phenomenological significance. We additionally describe in detail, both analytically and numerically, a striking feature in the invariant mass distribution appearing only in the $T \to th$ channel.
[ { "created": "Tue, 18 May 2021 18:02:36 GMT", "version": "v1" }, { "created": "Wed, 18 Aug 2021 14:45:42 GMT", "version": "v2" }, { "created": "Tue, 20 Sep 2022 05:07:27 GMT", "version": "v3" } ]
2022-12-15
[ [ "Deandrea", "Aldo", "" ], [ "Flacke", "Thomas", "" ], [ "Fuks", "Benjamin", "" ], [ "Panizzi", "Luca", "" ], [ "Shao", "Hua-Sheng", "" ] ]
We provide a comprehensive discussion, together with a complete setup for simulations, relevant for the production of a single vector-like quark at hadron colliders. Our predictions include finite width effects, signal-background interference effects and next-to-leading order QCD corrections. We explicitly apply the framework to study the single production of a vector-like quark $T$ with charge 2/3, but the same procedure can be used to analyse the single production of vector-like quarks with charge $-4/3$, $-1/3$, $2/3$ and $5/3$, when the vector-like quark interacts with the Standard Model quarks and electroweak bosons. Moreover, this procedure can be straightforwardly extended to include additional interactions with exotic particles. We provide quantitative results for representative benchmark scenarios characterised by the $T$ mass and width, and we determine the role of the interference terms for a range of masses and widths of phenomenological significance. We additionally describe in detail, both analytically and numerically, a striking feature in the invariant mass distribution appearing only in the $T \to th$ channel.
hep-ph/9705447
Stefan Groote
S. Groote, J.G. K\"orner, O.I. Yakovlev
An Analysis of Diagonal and Non-diagonal QCD Sum Rules for Heavy Baryons at Next-to-Leading Order in \alpha_S
17 pages, LaTeX, 8 figures are included in PostScript format
Phys. Rev. D 56, 3943 (1997)
10.1103/PhysRevD.56.3943
MZ-TH/97-19
hep-ph
null
We consider diagonal and non-diagonal QCD sum rules for the ground state heavy baryons to leading order in $1/m_Q$ and at next-to-leading order in $\alpha_S$. In the non-diagonal case we evaluate the eight different two-loop diagrams which determine the perturbative $\alpha_S$-corrections to the Wilson coefficient of the quark condensate in the Operator Product Expansion. The QCD corrections to the non-diagonal sum rules are moderate compared to the QCD corrections in the diagonal case. We also consider constituent type sum rules using constituent type interpolating currents. The obtained results are in reasonable agreement with the corresponding results obtained in the diagonal case. As central values for the bound state energies we find $m(\Lambda_Q)-m_Q = 760 MeV$ and $m(\Sigma_Q)-m_Q = 940 MeV$. The central values for the residues are given by $F(\Lambda_Q) = 0.030 GeV^3$ and $F(\Sigma_Q) = 0.038 GeV^3$.
[ { "created": "Wed, 28 May 1997 14:37:51 GMT", "version": "v1" } ]
2016-08-25
[ [ "Groote", "S.", "" ], [ "Körner", "J. G.", "" ], [ "Yakovlev", "O. I.", "" ] ]
We consider diagonal and non-diagonal QCD sum rules for the ground state heavy baryons to leading order in $1/m_Q$ and at next-to-leading order in $\alpha_S$. In the non-diagonal case we evaluate the eight different two-loop diagrams which determine the perturbative $\alpha_S$-corrections to the Wilson coefficient of the quark condensate in the Operator Product Expansion. The QCD corrections to the non-diagonal sum rules are moderate compared to the QCD corrections in the diagonal case. We also consider constituent type sum rules using constituent type interpolating currents. The obtained results are in reasonable agreement with the corresponding results obtained in the diagonal case. As central values for the bound state energies we find $m(\Lambda_Q)-m_Q = 760 MeV$ and $m(\Sigma_Q)-m_Q = 940 MeV$. The central values for the residues are given by $F(\Lambda_Q) = 0.030 GeV^3$ and $F(\Sigma_Q) = 0.038 GeV^3$.
1711.04880
Johannes Bl\"umlein
J. Ablinger, A. Behring, J. Bl\"umlein, G. Falcioni, A. De Freitas, P. Marquard, N. Rana, and C. Schneider
Heavy quark form factors at two loops in perturbative QCD
13 pages Latex, Proceedings of XLI International Conference of Theoretical Physics "Matter to the Deepest", Podlesice, Poland, September 3-8, 2017 and RADCOR 2017, St.~Gilgen Austria, Sept 24-29, 2017
null
10.5506/APhysPolB.48.2155
DESY 17--188, DO-TH 17/31, TTK-17-36, NIKHEF 2017-059
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present the results for heavy quark form factors at two-loop order in perturbative QCD for different currents, namely vector, axial-vector, scalar and pseudo-scalar currents, up to second order in the dimensional regularization parameter. We outline the necessary computational details, ultraviolet renormalization and corresponding universal infrared structure.
[ { "created": "Mon, 13 Nov 2017 22:47:51 GMT", "version": "v1" } ]
2018-05-09
[ [ "Ablinger", "J.", "" ], [ "Behring", "A.", "" ], [ "Blümlein", "J.", "" ], [ "Falcioni", "G.", "" ], [ "De Freitas", "A.", "" ], [ "Marquard", "P.", "" ], [ "Rana", "N.", "" ], [ "Schneider", "C.", "" ] ]
We present the results for heavy quark form factors at two-loop order in perturbative QCD for different currents, namely vector, axial-vector, scalar and pseudo-scalar currents, up to second order in the dimensional regularization parameter. We outline the necessary computational details, ultraviolet renormalization and corresponding universal infrared structure.
hep-ph/0508096
Mrinal Dasgupta
A.Banfi, G.Corcella, M.Dasgupta, Y.Delenda, G.P. Salam and G.Zanderighi
Resummation
15 pages, 6 figures. Submitted to the HERA-LHC workshop proceedings
null
null
null
hep-ph
null
We review the work discussed and developed under the topic ``Resummation'' at Working Group 2 ``Multijet final states and energy flow'', of the HERA-LHC Workshop. We emphasise the role played by HERA observables in the development of resummation tools via, for instance, the discovery and resummation of non-global logarithms. We describe the event-shapes subsequently developed for hadron colliders and present resummed predictions for the same using the automated resummation program CAESAR. We also point to ongoing studies at HERA which can be of benefit for future measurements at hadron colliders such as the LHC, specifically dijet $E_t$ and angular spectra and the transverse momentum of the Breit current hemisphere.
[ { "created": "Tue, 9 Aug 2005 16:06:03 GMT", "version": "v1" } ]
2016-09-06
[ [ "Banfi", "A.", "" ], [ "Corcella", "G.", "" ], [ "Dasgupta", "M.", "" ], [ "Delenda", "Y.", "" ], [ "Salam", "G. P.", "" ], [ "Zanderighi", "G.", "" ] ]
We review the work discussed and developed under the topic ``Resummation'' at Working Group 2 ``Multijet final states and energy flow'', of the HERA-LHC Workshop. We emphasise the role played by HERA observables in the development of resummation tools via, for instance, the discovery and resummation of non-global logarithms. We describe the event-shapes subsequently developed for hadron colliders and present resummed predictions for the same using the automated resummation program CAESAR. We also point to ongoing studies at HERA which can be of benefit for future measurements at hadron colliders such as the LHC, specifically dijet $E_t$ and angular spectra and the transverse momentum of the Breit current hemisphere.
1608.08858
Dmitry Karlovets
Dmitry V. Karlovets
Probing phase of a scattering amplitude beyond the plane-wave approximation
7 pages, 1 figure; the effect persists for relativistic energies
EPL, 116 (2016) 31001
10.1209/0295-5075/116/31001
null
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Within a plane-wave approach, a number of scattering events in a collision is insensitive to a general phase of a transition amplitude, although this phase is extremely important for a number of problems, especially in hadronic physics. In reality the particles are better described as wave packets, and here we show that the observables grow dependent upon this phase if one lays aside the simplified plane-wave model. We discuss two methods for probing how the Coulomb- and hadronic phases change with a transferred momentum $t$, either by colliding two beams at a non-vanishing impact-parameter or by employing such novel states as the vortex particles carrying orbital angular momentum or the Airy beams. For electron-electron collision, the phase contribution to a cross section can reach the values higher than $10^{-4} -- 10^{-3}$ for well-focused beams with energies of hundreds of keV.
[ { "created": "Wed, 31 Aug 2016 13:58:52 GMT", "version": "v1" }, { "created": "Wed, 14 Sep 2016 19:33:50 GMT", "version": "v2" }, { "created": "Fri, 2 Dec 2016 17:02:09 GMT", "version": "v3" } ]
2016-12-05
[ [ "Karlovets", "Dmitry V.", "" ] ]
Within a plane-wave approach, a number of scattering events in a collision is insensitive to a general phase of a transition amplitude, although this phase is extremely important for a number of problems, especially in hadronic physics. In reality the particles are better described as wave packets, and here we show that the observables grow dependent upon this phase if one lays aside the simplified plane-wave model. We discuss two methods for probing how the Coulomb- and hadronic phases change with a transferred momentum $t$, either by colliding two beams at a non-vanishing impact-parameter or by employing such novel states as the vortex particles carrying orbital angular momentum or the Airy beams. For electron-electron collision, the phase contribution to a cross section can reach the values higher than $10^{-4} -- 10^{-3}$ for well-focused beams with energies of hundreds of keV.
hep-ph/9407400
Yong Yeon Keum
M. Gourdin, A. N. Kamal, Y.Y. Keum and X. Y. Pham
Implications of factorization for the determination of hadronic form factors in $D_s^+ \ra \phi $ transition
Latex 10 pages( 4 figures), PAR/LPTHE/94-30
Phys.Lett. B339 (1994) 173-180
10.1016/0370-2693(94)91151-7
null
hep-ph
null
Using factorization we determine the allowed domains of the ratios of form factors, $x = A_2(0)/A_1(0)$ and $y = V(0)/A_1(0)$, from the experimentally measured ratio $R_h \equiv \Gamma(D_s^+ \ra \phi \rho^+)/\Gamma(D_s^+ \ra \phi \pi^+)$ assuming three different scenarios for the $q^2$-dependence of the form factors. We find that the allowed domains overlap with those obtained by using the experimentally measured ratio $R_{s\ell} = \Gamma(D^+_s \ra \phi \ell^+ \nu_{\ell})/\Gamma(D^+_s \ra \phi \pi^+)$ provided that the phenomenological parameter $a_1$ is $1.23$. Such a comparison presents a genuine test of factorization. We calculate the longitudinal polarization fraction, $\Gamma_L/\Gamma \equiv \Gamma(D_s^+ \ra \phi_L \rho^+_L)/\Gamma(D_s^+ \ra \phi \rho^+)$, in the three scenarios for the $q^2$-dependence of the form factors and emphasize the importance of measuring $\Gamma_L/\Gamma $. Finally we discuss the $q^2$-distribution of the semileptonic decay and find that it is rather insensitive to the scenarios for the $q^2$-dependence of the form factors, and unless very accurate data can be obtained it is unlikely to discriminate between the different scenarios. Useful information on the value of $x$ might be obtained by the magnitude of the $q^2$-distribution near $q^2 = 0$. However the most precise information on $x$ and $y$ would come from the knowledge of the longitudinal and left-right transverse polarizations of the final vector mesons in hadronic and/or semileptonic decays.
[ { "created": "Fri, 29 Jul 1994 14:12:54 GMT", "version": "v1" } ]
2009-10-28
[ [ "Gourdin", "M.", "" ], [ "Kamal", "A. N.", "" ], [ "Keum", "Y. Y.", "" ], [ "Pham", "X. Y.", "" ] ]
Using factorization we determine the allowed domains of the ratios of form factors, $x = A_2(0)/A_1(0)$ and $y = V(0)/A_1(0)$, from the experimentally measured ratio $R_h \equiv \Gamma(D_s^+ \ra \phi \rho^+)/\Gamma(D_s^+ \ra \phi \pi^+)$ assuming three different scenarios for the $q^2$-dependence of the form factors. We find that the allowed domains overlap with those obtained by using the experimentally measured ratio $R_{s\ell} = \Gamma(D^+_s \ra \phi \ell^+ \nu_{\ell})/\Gamma(D^+_s \ra \phi \pi^+)$ provided that the phenomenological parameter $a_1$ is $1.23$. Such a comparison presents a genuine test of factorization. We calculate the longitudinal polarization fraction, $\Gamma_L/\Gamma \equiv \Gamma(D_s^+ \ra \phi_L \rho^+_L)/\Gamma(D_s^+ \ra \phi \rho^+)$, in the three scenarios for the $q^2$-dependence of the form factors and emphasize the importance of measuring $\Gamma_L/\Gamma $. Finally we discuss the $q^2$-distribution of the semileptonic decay and find that it is rather insensitive to the scenarios for the $q^2$-dependence of the form factors, and unless very accurate data can be obtained it is unlikely to discriminate between the different scenarios. Useful information on the value of $x$ might be obtained by the magnitude of the $q^2$-distribution near $q^2 = 0$. However the most precise information on $x$ and $y$ would come from the knowledge of the longitudinal and left-right transverse polarizations of the final vector mesons in hadronic and/or semileptonic decays.
0912.2466
Gorazd Cvetic
Gorazd Cvetic, Reinhart Koegerler, and Cristian Valenzuela
Analytic QCD coupling with no power terms in UV regime
12 pages, 5 figures, revised version (short changes in the text, Refs.[21,22,23] are new), version as it appears in J.Phys.G37,075001
J.Phys.G37:075001,2010
10.1088/0954-3899/37/7/075001
USM-TH-253
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We construct models of analytic QCD (i.e.,with the running coupling parameter free of Landau singularities) which address several problems encountered in previous analytic QCD models, among them their incompatibility with the ITEP-OPE philosophy (due to UV power terms) and too low values of the semihadronic tau decay ratio. The starting point of the approach is the construction of appropriate nonperturbative beta functions.
[ { "created": "Sun, 13 Dec 2009 01:18:11 GMT", "version": "v1" }, { "created": "Tue, 22 Jun 2010 01:58:04 GMT", "version": "v2" } ]
2010-06-23
[ [ "Cvetic", "Gorazd", "" ], [ "Koegerler", "Reinhart", "" ], [ "Valenzuela", "Cristian", "" ] ]
We construct models of analytic QCD (i.e.,with the running coupling parameter free of Landau singularities) which address several problems encountered in previous analytic QCD models, among them their incompatibility with the ITEP-OPE philosophy (due to UV power terms) and too low values of the semihadronic tau decay ratio. The starting point of the approach is the construction of appropriate nonperturbative beta functions.
2106.02027
Wen-long Sang
Feng Feng (China University of Mining and Technology), Yu Jia (Institute of High Energy Physics, Chinese Academy of Sciences), Wen-Long Sang (Southwest University)
Next-to-leading-order QCD corrections to heavy quark fragmentation into ${}^1S^{(1,8)}_0$ quarkonia
11 pages, 2 figures
null
10.1140/epjc/s10052-021-09390-4
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Within NRQCD factorization framework, in this work we compute, at the lowest order in velocity expansion, the next-to-leading-order (NLO) perturbative corrections to the short-distance coefficients associated with heavy quark fragmentation into the ${}^1S_0^{(1,8)}$ components of a heavy quarkonium. Starting from the Collins and Soper's operator definition of the quark fragmentation function, we apply the sector decomposition method to facilitate the numerical manipulation. It is found that the NLO QCD corrections have a significant impact.
[ { "created": "Thu, 3 Jun 2021 17:52:17 GMT", "version": "v1" } ]
2021-07-28
[ [ "Feng", "Feng", "", "China University of Mining and Technology" ], [ "Jia", "Yu", "", "Institute of High Energy Physics, Chinese Academy of Sciences" ], [ "Sang", "Wen-Long", "", "Southwest University" ] ]
Within NRQCD factorization framework, in this work we compute, at the lowest order in velocity expansion, the next-to-leading-order (NLO) perturbative corrections to the short-distance coefficients associated with heavy quark fragmentation into the ${}^1S_0^{(1,8)}$ components of a heavy quarkonium. Starting from the Collins and Soper's operator definition of the quark fragmentation function, we apply the sector decomposition method to facilitate the numerical manipulation. It is found that the NLO QCD corrections have a significant impact.
hep-ph/9310232
Beatriz de Carlos
B. de Carlos and J.A. Casas
The Fine-Tuning Problem of the Electroweak Symmetry Breaking Mechanism in Minimal SUSY Models
talk given at the XVI Kazimierz Meeting on Elementary Particle Physics, Kazimierz (Poland) 24-28 May 1993, 4 pages in standard LATEX + 2 figures (not included but available upon request), CERN-TH.7024/93
null
null
null
hep-ph
null
We calculate the region of the MSSM parameter space (i.e. $M_{1/2}$, $m_{0}$, $\mu$, \ldots) compatible with a correct electroweak breaking and a realistic top-quark mass. To do so we have included {\em all} the one-loop corrections to the effective potential $V_{1}$ and checked their importance in order to obtain consistent results. We also consider the fine-tuning problem due to the enormous dependence of $M_{Z}$ on $h_{t}$ (the top Yukawa coupling), which is substantially reduced when the one-loop effects are taken into account. We also explore the reliability of the so-called "standard" criterion to estimate the degree of fine-tuning. As a consequence, we obtain a new set of upper bounds on the MSSM parameters or, equivalently, on the supersymmetric masses perfectly consistent with the present experimental bounds.
[ { "created": "Wed, 6 Oct 1993 10:08:57 GMT", "version": "v1" } ]
2007-05-23
[ [ "de Carlos", "B.", "" ], [ "Casas", "J. A.", "" ] ]
We calculate the region of the MSSM parameter space (i.e. $M_{1/2}$, $m_{0}$, $\mu$, \ldots) compatible with a correct electroweak breaking and a realistic top-quark mass. To do so we have included {\em all} the one-loop corrections to the effective potential $V_{1}$ and checked their importance in order to obtain consistent results. We also consider the fine-tuning problem due to the enormous dependence of $M_{Z}$ on $h_{t}$ (the top Yukawa coupling), which is substantially reduced when the one-loop effects are taken into account. We also explore the reliability of the so-called "standard" criterion to estimate the degree of fine-tuning. As a consequence, we obtain a new set of upper bounds on the MSSM parameters or, equivalently, on the supersymmetric masses perfectly consistent with the present experimental bounds.
0805.4368
Nicolas Matagne SE
N. Matagne, Fl. Stancu
Group Theoretical Analysis of the Wave Function of the $[{\bf 70},1^-]$ Nonstrange Baryons in the $1/N_c$ Expansion
14 pages, 12 tables, talk given by N. Matagne at the workshop "Three Days of Strong Interactions and Astrophysics", joint meeting Heidelberg-Liege-Paris-Wroclaw, March 6-8, 2008, Sol Cress, Spa, Belgium,to be published in AIP Proceedings
AIPConf.Proc.1038:278-291,2008
10.1063/1.2987181
null
hep-ph
http://creativecommons.org/licenses/publicdomain/
Using standard group theoretical techniques we construct the exact wave function of the $[{\bf 70},1^-]$ multiplet in the orbital, spin and flavor space. This symmetric wave function is compared to that customarily used in the $1/N_c$ expansion, which is asymmetric. The comparison is made by analyzing the matrix elements of various operators entering the mass formula. These matrix elements are calculated by the help of isoscalar factors of the permutation group, specially derived for this purpose as a function of $N_c$. We also compare two distinct methods used in the study of the $[{\bf 70},1^-]$ multiplet. In the first method the generators are divided into two parts, one part acting on a subsystem of $N_c-1$ quarks called core and another on the separated quark. In the second method the system is treated as a whole. We show that the latter is simpler and allows to clearly reveal the physically important operators in the mass formula.
[ { "created": "Wed, 28 May 2008 14:55:29 GMT", "version": "v1" } ]
2008-11-26
[ [ "Matagne", "N.", "" ], [ "Stancu", "Fl.", "" ] ]
Using standard group theoretical techniques we construct the exact wave function of the $[{\bf 70},1^-]$ multiplet in the orbital, spin and flavor space. This symmetric wave function is compared to that customarily used in the $1/N_c$ expansion, which is asymmetric. The comparison is made by analyzing the matrix elements of various operators entering the mass formula. These matrix elements are calculated by the help of isoscalar factors of the permutation group, specially derived for this purpose as a function of $N_c$. We also compare two distinct methods used in the study of the $[{\bf 70},1^-]$ multiplet. In the first method the generators are divided into two parts, one part acting on a subsystem of $N_c-1$ quarks called core and another on the separated quark. In the second method the system is treated as a whole. We show that the latter is simpler and allows to clearly reveal the physically important operators in the mass formula.
hep-ph/0703195
Kin-ya Oda
Yoshiharu Kawamura, Teppei Kinami, and Kin-ya Oda
Orbifold Family Unification
Comments added, version to appear in Physical Review D (v3); References added (v2); 19 pages (v1)
Phys.Rev.D76:035001,2007
10.1103/PhysRevD.76.035001
RIKEN-TH-94
hep-ph
null
We study the possibility of complete family unification in higher-dimensional space-time. Three families of matters in SU(5) grand unified theory are derived from a single bulk multiplet of SU(N) gauge group (N >= 9) in the framework of S^1/Z_2 orbifold models. In the case of the direct orbifold breaking down to the standard model gauge group, there are models in which bulk fields from a single multiplet and a few brane fields compose three families of quarks and leptons.
[ { "created": "Mon, 19 Mar 2007 05:59:44 GMT", "version": "v1" }, { "created": "Sat, 24 Mar 2007 08:52:30 GMT", "version": "v2" }, { "created": "Sat, 9 Jun 2007 10:11:16 GMT", "version": "v3" } ]
2008-11-26
[ [ "Kawamura", "Yoshiharu", "" ], [ "Kinami", "Teppei", "" ], [ "Oda", "Kin-ya", "" ] ]
We study the possibility of complete family unification in higher-dimensional space-time. Three families of matters in SU(5) grand unified theory are derived from a single bulk multiplet of SU(N) gauge group (N >= 9) in the framework of S^1/Z_2 orbifold models. In the case of the direct orbifold breaking down to the standard model gauge group, there are models in which bulk fields from a single multiplet and a few brane fields compose three families of quarks and leptons.
0904.1644
Yoshio Koide
Yoshio Koide
Yukawaon Model in the Quark Sector and Nearly Tribimaximal Neutrino Mixing
10 pages, no figure, version accepted by Phys.Lett.B
null
10.1016/j.physletb.2009.08.038
OU-HET 633/2009
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
For the purpose of deriving the observed nearly tribimaximal neutrino mixing, a possible yukawaon model in the quark sector is investigated. Five observable quantities (2 up-quark mass ratios and 3 neutrino mixing parameters \sin^2 2\theta_{atm}, \tan^2\theta_{solar} and |U_{13}|) are excellently fitted by two parameters (one in the up-quark sector and another one in the right-handed Majorana neutrino sector).
[ { "created": "Fri, 10 Apr 2009 06:27:52 GMT", "version": "v1" }, { "created": "Tue, 14 Apr 2009 11:24:08 GMT", "version": "v2" }, { "created": "Thu, 11 Jun 2009 07:29:30 GMT", "version": "v3" }, { "created": "Tue, 14 Jul 2009 01:02:59 GMT", "version": "v4" }, { "created": "Tue, 25 Aug 2009 07:05:11 GMT", "version": "v5" } ]
2009-08-25
[ [ "Koide", "Yoshio", "" ] ]
For the purpose of deriving the observed nearly tribimaximal neutrino mixing, a possible yukawaon model in the quark sector is investigated. Five observable quantities (2 up-quark mass ratios and 3 neutrino mixing parameters \sin^2 2\theta_{atm}, \tan^2\theta_{solar} and |U_{13}|) are excellently fitted by two parameters (one in the up-quark sector and another one in the right-handed Majorana neutrino sector).
1507.06732
Shu-Min Zhao
Shu-Min Zhao, Tai-Fu Feng, Hai-Bin Zhang, Xi-Jie Zhan, Yin-Jie Zhang, Ben Yan
Lepton flavor violation in the BLMSSM
27 pages,18 figures
Phys. Rev. D 92, 115016 (2015)
10.1103/PhysRevD.92.115016
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a supersymmetric extension of the standard model with local gauged baryon and lepton numbers (BLMSSM), there are new sources for lepton flavor violation, because the right-handed neutrinos and new gauginos are introduced. In BLMSSM, we study the charged lepton flavor violating processes $l_j\rightarrow l_i+\gamma$ and $l_j\rightarrow 3l_i$ in detail. The numerical results show that in some parameter space the branching ratios for charged lepton flavor violating processes can be large enough to be detected in the near future.
[ { "created": "Fri, 24 Jul 2015 02:46:38 GMT", "version": "v1" }, { "created": "Sat, 14 Nov 2015 10:08:20 GMT", "version": "v2" } ]
2015-12-23
[ [ "Zhao", "Shu-Min", "" ], [ "Feng", "Tai-Fu", "" ], [ "Zhang", "Hai-Bin", "" ], [ "Zhan", "Xi-Jie", "" ], [ "Zhang", "Yin-Jie", "" ], [ "Yan", "Ben", "" ] ]
In a supersymmetric extension of the standard model with local gauged baryon and lepton numbers (BLMSSM), there are new sources for lepton flavor violation, because the right-handed neutrinos and new gauginos are introduced. In BLMSSM, we study the charged lepton flavor violating processes $l_j\rightarrow l_i+\gamma$ and $l_j\rightarrow 3l_i$ in detail. The numerical results show that in some parameter space the branching ratios for charged lepton flavor violating processes can be large enough to be detected in the near future.
hep-ph/9310377
Arturo De Pace
V.V. Burov, A. De Pace, S.M. Dorkin and P. Saracco
Hadron and Quark Form Factors in the Relativistic Harmonic Oscillator Model
9 pages, Latex, 3 postscript figures, DFTT 8/93
Europhys.Lett.24:443-448,1993
10.1209/0295-5075/24/6/003
null
hep-ph
null
Nucleon, pion and quark form factors are studied within the relativistic harmonic oscillator model including the quark spin. It is shown that the nucleon charge, magnetic and axial form factors and the pion charge form factor can be explained with one oscillator parameter if one accounts for the scaling rule and the size of the constituent quarks.
[ { "created": "Fri, 29 Oct 1993 23:12:26 GMT", "version": "v1" } ]
2010-12-17
[ [ "Burov", "V. V.", "" ], [ "De Pace", "A.", "" ], [ "Dorkin", "S. M.", "" ], [ "Saracco", "P.", "" ] ]
Nucleon, pion and quark form factors are studied within the relativistic harmonic oscillator model including the quark spin. It is shown that the nucleon charge, magnetic and axial form factors and the pion charge form factor can be explained with one oscillator parameter if one accounts for the scaling rule and the size of the constituent quarks.
hep-ph/0409330
Kenji Kadota
Kenji Kadota, Ewan D. Stewart
Inflation model building in moduli space
5 pages, to appear in PASCOS04 proceedings
null
10.1142/9789812701756_0007
FERMILAB-PUB-04-240-A
hep-ph astro-ph hep-th
null
A self-consistent modular cosmology scenario and its testability in view of future CMB experiments are discussed. Particular attention is drawn to the enhanced symmetric points in moduli space which play crucial roles in our scenario. The running and moreover the running of running for the cosmic perturbation spectrum are also analyzed.
[ { "created": "Wed, 29 Sep 2004 06:06:32 GMT", "version": "v1" } ]
2015-06-25
[ [ "Kadota", "Kenji", "" ], [ "Stewart", "Ewan D.", "" ] ]
A self-consistent modular cosmology scenario and its testability in view of future CMB experiments are discussed. Particular attention is drawn to the enhanced symmetric points in moduli space which play crucial roles in our scenario. The running and moreover the running of running for the cosmic perturbation spectrum are also analyzed.
1203.6341
Kristian McDonald
Kristian L. McDonald
Sommerfeld Enhancement from Multiple Mediators
17p, 2 figures; v2 JHEP version (inconsequential typo fixed, references added)
null
10.1007/JHEP07(2012)145
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the Sommerfeld enhancement experienced by a scattering object that couples to a tower of mediators. This can occur in, e.g., models of secluded dark matter when the mediator scale is generated naturally by hidden-sector confinement. Specializing to the case of a confining CFT, we show that off-resonant values of the enhancement can be increased by ~ 20% for cases of interest when (i) the (strongly-coupled) CFT admits a weakly-coupled dual description and (ii) the conformal symmetry holds up to the Planck scale. Larger enhancements are possible for lower UV scales due to an increase in the coupling strength of the tower.
[ { "created": "Wed, 28 Mar 2012 19:08:05 GMT", "version": "v1" }, { "created": "Sat, 30 Mar 2013 11:19:55 GMT", "version": "v2" } ]
2017-08-23
[ [ "McDonald", "Kristian L.", "" ] ]
We study the Sommerfeld enhancement experienced by a scattering object that couples to a tower of mediators. This can occur in, e.g., models of secluded dark matter when the mediator scale is generated naturally by hidden-sector confinement. Specializing to the case of a confining CFT, we show that off-resonant values of the enhancement can be increased by ~ 20% for cases of interest when (i) the (strongly-coupled) CFT admits a weakly-coupled dual description and (ii) the conformal symmetry holds up to the Planck scale. Larger enhancements are possible for lower UV scales due to an increase in the coupling strength of the tower.
1702.05733
Kapil Saraswat
Kapil Saraswat, Prashant Shukla, Vineet Kumar, Venktesh Singh
Energy loss of heavy quarks and $B$ and $D$ meson spectra in PbPb collisions at LHC energies
null
null
10.1016/j.nuclphysa.2017.02.013
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the production and evolution of charm and bottom quarks in hot partonic medium produced in heavy ion collisions. The heavy quarks loose energy in the medium which is reflected in the transverse momentum spectra of heavy mesons. The collisional energy loss of heavy quarks has been calculated using QCD calculations. The radiative energy loss is obtained using two models namely reaction operator formalism and generalized dead cone approach. The nuclear modification factors, $R_{AA}$ as a function of transverse momentum by including shadowing and energy loss are calculated for $D^{0}$ and $B^{+}$ mesons in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV and for $D^{0}$ mesons at $\sqrt{s_{NN}}$ = 2.76 TeV and are compared with the recent measurements. The radiative energy loss from generalized dead cone approach alone is sufficient to produce measured $D^{0}$ meson $R_{AA}$ at both the LHC energies. The radiative energy loss from reaction operator formalism plus collisional energy loss gives good description of $D^{0}$ meson $R_{AA}$. For the case of $B^{+}$ meson, the radiative energy loss from generalized dead cone approach plus collisional energy loss gives good description of the CMS data. The radiative process is dominant for charm quarks while for the bottom, both the radiative process and the elastic collisions are important.
[ { "created": "Sun, 19 Feb 2017 10:17:25 GMT", "version": "v1" } ]
2017-04-05
[ [ "Saraswat", "Kapil", "" ], [ "Shukla", "Prashant", "" ], [ "Kumar", "Vineet", "" ], [ "Singh", "Venktesh", "" ] ]
We study the production and evolution of charm and bottom quarks in hot partonic medium produced in heavy ion collisions. The heavy quarks loose energy in the medium which is reflected in the transverse momentum spectra of heavy mesons. The collisional energy loss of heavy quarks has been calculated using QCD calculations. The radiative energy loss is obtained using two models namely reaction operator formalism and generalized dead cone approach. The nuclear modification factors, $R_{AA}$ as a function of transverse momentum by including shadowing and energy loss are calculated for $D^{0}$ and $B^{+}$ mesons in PbPb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV and for $D^{0}$ mesons at $\sqrt{s_{NN}}$ = 2.76 TeV and are compared with the recent measurements. The radiative energy loss from generalized dead cone approach alone is sufficient to produce measured $D^{0}$ meson $R_{AA}$ at both the LHC energies. The radiative energy loss from reaction operator formalism plus collisional energy loss gives good description of $D^{0}$ meson $R_{AA}$. For the case of $B^{+}$ meson, the radiative energy loss from generalized dead cone approach plus collisional energy loss gives good description of the CMS data. The radiative process is dominant for charm quarks while for the bottom, both the radiative process and the elastic collisions are important.
hep-ph/0606210
Tord Riemann
J. Fleischer, J. Gluza, A. Lorca, T. Riemann
First order radiative corrections to Bhabha scattering in $d$ dimensions
35 pages, 3 figures, 2 tables, uses feynmp.sty, references updated
Eur.J.Phys.48:35-52,2006
10.1140/epjc/s10052-006-0008-6
DESY 06-045, BI-TP 2006/21, Freiburg-THEP 06/07, SFB/CPP-06-27
hep-ph
null
The luminosity measurement at the projected International Linear $e^+e^-$ Collider ILC is planned to be performed with forward Bhabha scattering with an accuracy of the order of $10^{-4}$. A theoretical prediction of the differential cross-section has to include one-loop weak corrections, with leading higher order terms, and the complete two-loop QED corrections. Here, we present the weak part and the virtual one-loop photonic corrections. For the photonic corrections, the expansions in $\epsilon = (4-d)/2$ are derived with inclusion of the terms of order $\epsilon$ in order to match the two-loop accuracy. For the photonic box master integral in $d$ dimensions we compare several different methods of evaluation.
[ { "created": "Tue, 20 Jun 2006 12:30:03 GMT", "version": "v1" }, { "created": "Thu, 22 Jun 2006 11:24:02 GMT", "version": "v2" } ]
2009-11-11
[ [ "Fleischer", "J.", "" ], [ "Gluza", "J.", "" ], [ "Lorca", "A.", "" ], [ "Riemann", "T.", "" ] ]
The luminosity measurement at the projected International Linear $e^+e^-$ Collider ILC is planned to be performed with forward Bhabha scattering with an accuracy of the order of $10^{-4}$. A theoretical prediction of the differential cross-section has to include one-loop weak corrections, with leading higher order terms, and the complete two-loop QED corrections. Here, we present the weak part and the virtual one-loop photonic corrections. For the photonic corrections, the expansions in $\epsilon = (4-d)/2$ are derived with inclusion of the terms of order $\epsilon$ in order to match the two-loop accuracy. For the photonic box master integral in $d$ dimensions we compare several different methods of evaluation.
0811.1779
Mridupawan Deka
M. Deka, T. Streuer, T. Doi, S. J. Dong, T. Draper, K. F. Liu, N. Mathur, A. W. Thomas
Moments of Nucleon's Parton Distribution for the Sea and Valence Quarks from Lattice QCD
50 Pages 58 Figures
Phys.Rev.D79:094502,2009
10.1103/PhysRevD.79.094502
null
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We extend the study of lowest moments, $<x>$ and $<x^2>$, of the parton distribution function of the nucleon to include those of the sea quarks; this entails a disconnected insertion calculation in lattice QCD. This is carried out on a $16^3 \times 24$ quenched lattice with Wilson fermion. The quark loops are calculated with $Z_2$ noise vectors and unbiased subtractions, and multiple nucleon sources are employed to reduce the statistical errors. We obtain 5$\sigma$ signals for $<x>$ for the $u,d,$ and $s$ quarks, but $<x^2>$ is consistent with zero within errors. We provide results for both the connected and disconnected insertions. The perturbatively renormalized $<x>$ for the strange quark at $\mu = 2$ GeV is $<x>_{s+\bar{s}} = 0.027 \pm 0.006$ which is consistent with the experimental result. The ratio of $<x>$ for $s$ vs. $u/d$ in the disconnected insertion with quark loops is calculated to be $0.88 \pm 0.07$. This is about twice as large as the phenomenologically fitted $\displaystyle\frac{< x>_{s+\bar{s}}}{< x>_{\bar{u}}+< x>_{\bar{d}}}$ from experiments where $\bar{u}$ and $\bar{d}$ include both the connected and disconnected insertion parts. We discuss the source and implication of this difference.
[ { "created": "Tue, 11 Nov 2008 21:08:04 GMT", "version": "v1" } ]
2010-04-21
[ [ "Deka", "M.", "" ], [ "Streuer", "T.", "" ], [ "Doi", "T.", "" ], [ "Dong", "S. J.", "" ], [ "Draper", "T.", "" ], [ "Liu", "K. F.", "" ], [ "Mathur", "N.", "" ], [ "Thomas", "A. W.", "" ] ]
We extend the study of lowest moments, $<x>$ and $<x^2>$, of the parton distribution function of the nucleon to include those of the sea quarks; this entails a disconnected insertion calculation in lattice QCD. This is carried out on a $16^3 \times 24$ quenched lattice with Wilson fermion. The quark loops are calculated with $Z_2$ noise vectors and unbiased subtractions, and multiple nucleon sources are employed to reduce the statistical errors. We obtain 5$\sigma$ signals for $<x>$ for the $u,d,$ and $s$ quarks, but $<x^2>$ is consistent with zero within errors. We provide results for both the connected and disconnected insertions. The perturbatively renormalized $<x>$ for the strange quark at $\mu = 2$ GeV is $<x>_{s+\bar{s}} = 0.027 \pm 0.006$ which is consistent with the experimental result. The ratio of $<x>$ for $s$ vs. $u/d$ in the disconnected insertion with quark loops is calculated to be $0.88 \pm 0.07$. This is about twice as large as the phenomenologically fitted $\displaystyle\frac{< x>_{s+\bar{s}}}{< x>_{\bar{u}}+< x>_{\bar{d}}}$ from experiments where $\bar{u}$ and $\bar{d}$ include both the connected and disconnected insertion parts. We discuss the source and implication of this difference.
2001.07032
Neil Barrie Dr.
Neil D. Barrie, Akio Sugamoto, Tatsu Takeuchi, and Kimiko Yamashita
Higgs Inflation, Vacuum Stability, and Leptogenesis
40 pages, 6 figures, minor revisions for consistency with published version
JHEP 08 (2020) 072
10.1007/JHEP08(2020)072
IPMU19-0175, OCHA-PP-359
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider the introduction of a complex scalar field carrying a global lepton number charge to the Standard Model and the Higgs inflation framework. The conditions are investigated under which this model can simultaneously ensure Higgs vacuum stability up to the Planck scale, successful inflation, non-thermal Leptogenesis via the pendulum mechanism, and light neutrino masses. These can be simultaneously achieved when the scalar lepton is minimally coupled to gravity, that is, when standard Higgs inflation and reheating proceed without the interference of the additional scalar degrees of freedom. If the scalar lepton also has a non-minimal coupling to gravity, a multi-field inflation scenario is induced, with interesting interplay between the successful inflation constraints and those from vacuum stability and Leptogenesis. The parameter region that can simultaneously achieve the above goals is explored.
[ { "created": "Mon, 20 Jan 2020 09:45:10 GMT", "version": "v1" }, { "created": "Sun, 8 Nov 2020 07:35:14 GMT", "version": "v2" } ]
2020-11-10
[ [ "Barrie", "Neil D.", "" ], [ "Sugamoto", "Akio", "" ], [ "Takeuchi", "Tatsu", "" ], [ "Yamashita", "Kimiko", "" ] ]
We consider the introduction of a complex scalar field carrying a global lepton number charge to the Standard Model and the Higgs inflation framework. The conditions are investigated under which this model can simultaneously ensure Higgs vacuum stability up to the Planck scale, successful inflation, non-thermal Leptogenesis via the pendulum mechanism, and light neutrino masses. These can be simultaneously achieved when the scalar lepton is minimally coupled to gravity, that is, when standard Higgs inflation and reheating proceed without the interference of the additional scalar degrees of freedom. If the scalar lepton also has a non-minimal coupling to gravity, a multi-field inflation scenario is induced, with interesting interplay between the successful inflation constraints and those from vacuum stability and Leptogenesis. The parameter region that can simultaneously achieve the above goals is explored.
2404.06905
Hannes Jung
H. Jung
The non-perturbative Sudakov Form Factor and the role of soft gluons
Presented at Cracow Epiphany Conference 2024, (typos corrected)
null
null
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The role of soft gluons in inclusive collinear parton densities as well as in Transverse Momentum Dependent (TMD) parton densities is discussed. Applying the Parton-Branching (PBM) method, the so-called non-perturbative Sudakov form factor could be identified with the integration range $z \to 1$, which is neglected in collinear parton shower approaches. The importance of soft gluons could be shown by investigating the transverse momentum spectrum of Drell-Yan lepton pairs, leading to a width of the intrinsic-$k_T$ distribution which is independent on $\sqrt{s}$ , in contrast to what is observed in parton shower approaches. The reason for this behavior is traced back to the non-perturbative Sudakov form factor. The role of soft gluons for observable hadron spectra is discussed and shown to be negligible. This talk is dedicated to the memory of S. Jadach.
[ { "created": "Wed, 10 Apr 2024 10:51:37 GMT", "version": "v1" }, { "created": "Thu, 23 May 2024 16:04:14 GMT", "version": "v2" } ]
2024-05-24
[ [ "Jung", "H.", "" ] ]
The role of soft gluons in inclusive collinear parton densities as well as in Transverse Momentum Dependent (TMD) parton densities is discussed. Applying the Parton-Branching (PBM) method, the so-called non-perturbative Sudakov form factor could be identified with the integration range $z \to 1$, which is neglected in collinear parton shower approaches. The importance of soft gluons could be shown by investigating the transverse momentum spectrum of Drell-Yan lepton pairs, leading to a width of the intrinsic-$k_T$ distribution which is independent on $\sqrt{s}$ , in contrast to what is observed in parton shower approaches. The reason for this behavior is traced back to the non-perturbative Sudakov form factor. The role of soft gluons for observable hadron spectra is discussed and shown to be negligible. This talk is dedicated to the memory of S. Jadach.
1011.0348
Florian Staub
J. N. Esteves, M. Hirsch, W. Porod, J. C. Romao, F. Staub, A. Vicente
LHC and lepton flavour violation phenomenology of a left-right extension of the MSSM
43 pages, 17 figures
JHEP 1012:077,2010
10.1007/JHEP12(2010)077
CFTP/10-014, IFIC/10-43
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the phenomenology of a supersymmetric left-right model, assuming minimal supergravity boundary conditions. Both left-right and (B-L) symmetries are broken at an energy scale close to, but significantly below the GUT scale. Neutrino data is explained via a seesaw mechanism. We calculate the RGEs for superpotential and soft parameters complete at 2-loop order. At low energies lepton flavour violation (LFV) and small, but potentially measurable mass splittings in the charged scalar lepton sector appear, due to the RGE running. Different from the supersymmetric 'pure seesaw' models, both, LFV and slepton mass splittings, occur not only in the left- but also in the right slepton sector. Especially, ratios of LFV slepton decays, such as Br(${\tilde\tau}_R \to \mu \chi^0_1$)/Br(${\tilde\tau}_L \to \mu \chi^0_1$) are sensitive to the ratio of (B-L) and left-right symmetry breaking scales. Also the model predicts a polarization asymmetry of the outgoing positrons in the decay $\mu^+ \to e^+ \gamma$, A ~ [0,1], which differs from the pure seesaw 'prediction' A=1$. Observation of any of these signals allows to distinguish this model from any of the three standard, pure (mSugra) seesaw setups.
[ { "created": "Mon, 1 Nov 2010 15:38:20 GMT", "version": "v1" } ]
2011-01-27
[ [ "Esteves", "J. N.", "" ], [ "Hirsch", "M.", "" ], [ "Porod", "W.", "" ], [ "Romao", "J. C.", "" ], [ "Staub", "F.", "" ], [ "Vicente", "A.", "" ] ]
We study the phenomenology of a supersymmetric left-right model, assuming minimal supergravity boundary conditions. Both left-right and (B-L) symmetries are broken at an energy scale close to, but significantly below the GUT scale. Neutrino data is explained via a seesaw mechanism. We calculate the RGEs for superpotential and soft parameters complete at 2-loop order. At low energies lepton flavour violation (LFV) and small, but potentially measurable mass splittings in the charged scalar lepton sector appear, due to the RGE running. Different from the supersymmetric 'pure seesaw' models, both, LFV and slepton mass splittings, occur not only in the left- but also in the right slepton sector. Especially, ratios of LFV slepton decays, such as Br(${\tilde\tau}_R \to \mu \chi^0_1$)/Br(${\tilde\tau}_L \to \mu \chi^0_1$) are sensitive to the ratio of (B-L) and left-right symmetry breaking scales. Also the model predicts a polarization asymmetry of the outgoing positrons in the decay $\mu^+ \to e^+ \gamma$, A ~ [0,1], which differs from the pure seesaw 'prediction' A=1$. Observation of any of these signals allows to distinguish this model from any of the three standard, pure (mSugra) seesaw setups.
hep-ph/0010003
David Garcia
M. Carena, D. Garcia, U. Nierste and C.E.M. Wagner
b -> s \gamma and supersymmetry with large tan\beta
"Note added" changed, 2 references and 2 footnotes added
Phys.Lett.B499:141-146,2001
10.1016/S0370-2693(01)00009-0
CERN-TH/2000-295
hep-ph
null
We discuss the constraints on the supersymmetric parameter space from the decay mode b -> s \gamma for large values of tan\beta. We improve the theoretical prediction for the decay rate by summing very large radiative corrections to all orders in perturbation theory. This extends the validity of the perturbative calculation to the large tan\beta regime. This resummation of terms of order alpha_s^n tan^{n+1}\beta uses a recently proposed effective lagrangian for the Yukawa interaction of bottom quarks. Moreover, we identify an additional source of tan\beta-enhanced terms, which are of order alpha_s tan\beta and involve the charged Higgs boson, and analyze their behaviour in higher orders of perturbation theory. After correcting the current expressions for this rare decay branching ratio at next-to-leading order, we obtain that, contrary to recent claims, the presently measured branching ratio of b -> s \gamma constrains the supersymmetric parameter space in a relevant way, even if tan\beta is large.
[ { "created": "Mon, 2 Oct 2000 22:21:22 GMT", "version": "v1" }, { "created": "Wed, 11 Oct 2000 16:28:35 GMT", "version": "v2" } ]
2008-11-26
[ [ "Carena", "M.", "" ], [ "Garcia", "D.", "" ], [ "Nierste", "U.", "" ], [ "Wagner", "C. E. M.", "" ] ]
We discuss the constraints on the supersymmetric parameter space from the decay mode b -> s \gamma for large values of tan\beta. We improve the theoretical prediction for the decay rate by summing very large radiative corrections to all orders in perturbation theory. This extends the validity of the perturbative calculation to the large tan\beta regime. This resummation of terms of order alpha_s^n tan^{n+1}\beta uses a recently proposed effective lagrangian for the Yukawa interaction of bottom quarks. Moreover, we identify an additional source of tan\beta-enhanced terms, which are of order alpha_s tan\beta and involve the charged Higgs boson, and analyze their behaviour in higher orders of perturbation theory. After correcting the current expressions for this rare decay branching ratio at next-to-leading order, we obtain that, contrary to recent claims, the presently measured branching ratio of b -> s \gamma constrains the supersymmetric parameter space in a relevant way, even if tan\beta is large.
1007.5439
Philipp Kant
Philipp Kant
Three-loop corrections to the mass of the light Higgs boson in the MSSM
4 pages, 3 figures, contribution to the proceedings of the European Physical Society Europhysics Conference on High Energy Physics 2009, Krakow, Poland
PoS EPS-HEP2009:236,2009
null
SFB/CPP-10-70
hep-ph
http://creativecommons.org/licenses/by-nc-sa/3.0/
The Minimal Supersymmetric extension of the Standard Model (MSSM) predicts the existence of a light neutral Higgs boson. Once found at the LHC, its mass will immediately become a precision observable. The theoretical value of the Higgs mass Mh is subject to large radiative corrections. Due to the large top Yukawa coupling, loops of top quarks and their superpartners provide the dominant contribution to the radiative corrections. We present a calculation of the SUSY-QCD corrections to these diagrams, up to the three-loop order. We find that our three-loop results can be in the range of one GeV, and are thus relevant when compared with the expected experimental accuracy at the LHC. We also find a significantly reduced dependency on the renormalisation prescription, thus decreasing the theoretical uncertainty of the prediction of Mh.
[ { "created": "Fri, 30 Jul 2010 13:21:29 GMT", "version": "v1" } ]
2014-11-21
[ [ "Kant", "Philipp", "" ] ]
The Minimal Supersymmetric extension of the Standard Model (MSSM) predicts the existence of a light neutral Higgs boson. Once found at the LHC, its mass will immediately become a precision observable. The theoretical value of the Higgs mass Mh is subject to large radiative corrections. Due to the large top Yukawa coupling, loops of top quarks and their superpartners provide the dominant contribution to the radiative corrections. We present a calculation of the SUSY-QCD corrections to these diagrams, up to the three-loop order. We find that our three-loop results can be in the range of one GeV, and are thus relevant when compared with the expected experimental accuracy at the LHC. We also find a significantly reduced dependency on the renormalisation prescription, thus decreasing the theoretical uncertainty of the prediction of Mh.
hep-ph/9411420
Johan Bijnens
Johan Bijnens
Effective Lagrangians for Light Quarks
LaTeX, 16 pages, 4 figures (included, uses epsf.sty, talk presented at Perspectives in Particle Physics 94, Brijuni, Croatia, Sept. 94
null
null
NORDITA - 94/65 N,P
hep-ph
null
The class of phenomenological Lagrangians used for light constituent quarks is discussed. The Nambu-Jona-Lasinio model is then argued to be a good phenomenological choice and the quality of its prediction in the purely hadronic sector including several relations between parameters illustrated. Then we use these models to calculate nonleptonic matrix elements. The $\pi^+-\pi^0$ mass difference and the $B_K$ parameter, relevant in $K^0-\overline{K}^0$ mixing, are treated in more detail.
[ { "created": "Tue, 29 Nov 1994 11:16:44 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bijnens", "Johan", "" ] ]
The class of phenomenological Lagrangians used for light constituent quarks is discussed. The Nambu-Jona-Lasinio model is then argued to be a good phenomenological choice and the quality of its prediction in the purely hadronic sector including several relations between parameters illustrated. Then we use these models to calculate nonleptonic matrix elements. The $\pi^+-\pi^0$ mass difference and the $B_K$ parameter, relevant in $K^0-\overline{K}^0$ mixing, are treated in more detail.
hep-ph/0409304
Ilya Narodetskii
I.M. Narodetskii, C. Semay, B. Silvestre-Brac, and Yu.A. Simonov
Pentaquarks in string dynamics
5 pages. Based on talk by I.M.Narodetskii at BEACH 2004, 6th International Conference on Hyperons, Charm and Beauty Hadrons, Illionois Institute of Technology, Chicago, June. 27 - July 3, 2004. Typos corrected
null
10.1016/j.nuclphysbps.2005.01.064
null
hep-ph
null
The masses of $uudd\bar s $, $uudd\bar d$, and $uuss\bar d$ pentaquarks are evaluated in a framework of both the Effective Hamiltonian approach to QCD and spinless Salpeter using the Jaffe-Wilczek diquark approximation and the string interaction for the diquark-diquark-antiquark system. The masses of the light pentaquarks are found to be in the region above 2 GeV. The similar calculations yield the mass of $[ud]^2\bar c$ pentaquark $\sim$ 3250 MeV and $[ud]^2\bar b$ pentaquark $\sim$ 6509 MeV.
[ { "created": "Mon, 27 Sep 2004 12:40:55 GMT", "version": "v1" }, { "created": "Thu, 30 Dec 2004 16:57:38 GMT", "version": "v2" } ]
2009-11-10
[ [ "Narodetskii", "I. M.", "" ], [ "Semay", "C.", "" ], [ "Silvestre-Brac", "B.", "" ], [ "Simonov", "Yu. A.", "" ] ]
The masses of $uudd\bar s $, $uudd\bar d$, and $uuss\bar d$ pentaquarks are evaluated in a framework of both the Effective Hamiltonian approach to QCD and spinless Salpeter using the Jaffe-Wilczek diquark approximation and the string interaction for the diquark-diquark-antiquark system. The masses of the light pentaquarks are found to be in the region above 2 GeV. The similar calculations yield the mass of $[ud]^2\bar c$ pentaquark $\sim$ 3250 MeV and $[ud]^2\bar b$ pentaquark $\sim$ 6509 MeV.
1404.6270
Yachao Qian
Yachao Qian and Ismail Zahed
Double Spin Asymmetries through QCD Instantons
7 pages, 9 figures
Phys. Rev. D 90, 114012 (2014)
10.1103/PhysRevD.90.114012
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We revisit the large instanton contribution to the gluon Pauli form factor of the constituent quark noted by Kochelev. We check that it contributes sizably to the single spin asymmetry in polarized $p_\uparrow p \rightarrow \pi X$. We use it to predict a large double spin asymmetry in doubly polarized $p_\uparrow p_\uparrow\rightarrow \pi \pi X$.
[ { "created": "Thu, 24 Apr 2014 21:19:55 GMT", "version": "v1" } ]
2014-12-17
[ [ "Qian", "Yachao", "" ], [ "Zahed", "Ismail", "" ] ]
We revisit the large instanton contribution to the gluon Pauli form factor of the constituent quark noted by Kochelev. We check that it contributes sizably to the single spin asymmetry in polarized $p_\uparrow p \rightarrow \pi X$. We use it to predict a large double spin asymmetry in doubly polarized $p_\uparrow p_\uparrow\rightarrow \pi \pi X$.
0806.4172
David Mateos
Jorge Casalderrey-Solana and David Mateos
Prediction of a Photon Peak in Heavy Ion Collisions
4 pages, 5 figures. Minor corrections; references added
Phys.Rev.Lett.102:192302,2009
10.1103/PhysRevLett.102.192302
null
hep-ph hep-ex hep-th nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that if a flavour-less vector meson remains bound after deconfinement, and if its limiting velocity in the quark-gluon plasma is subluminal, then this meson produces a distinct peak in the spectrum of thermal photons emitted by the plasma. We also demonstrate that this effect is a universal property of all strongly coupled, large-Nc plasmas with a gravity dual. For the J/psi the corresponding peak lies between 3 and 5 GeV and could be observed at LHC.
[ { "created": "Wed, 25 Jun 2008 18:41:35 GMT", "version": "v1" }, { "created": "Wed, 16 Jul 2008 21:46:51 GMT", "version": "v2" } ]
2009-06-30
[ [ "Casalderrey-Solana", "Jorge", "" ], [ "Mateos", "David", "" ] ]
We show that if a flavour-less vector meson remains bound after deconfinement, and if its limiting velocity in the quark-gluon plasma is subluminal, then this meson produces a distinct peak in the spectrum of thermal photons emitted by the plasma. We also demonstrate that this effect is a universal property of all strongly coupled, large-Nc plasmas with a gravity dual. For the J/psi the corresponding peak lies between 3 and 5 GeV and could be observed at LHC.
0808.3965
Brian C. Tiburzi
Brian C. Tiburzi
Hadrons in Strong Electric and Magnetic Fields
37 pages, 11 figures. Version to be published, a few clarifications and references added
Nucl.Phys.A814:74-108,2008
10.1016/j.nuclphysa.2008.10.010
UMD-40762-426
hep-ph hep-lat nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We use chiral perturbation theory to investigate hadronic properties in strong electric and magnetic fields. A strong-field power counting is employed, and results for pions and nucleons are obtained using Schwinger's proper-time method. In the limit of weak fields, we accordingly recover the well known one-loop chiral perturbation theory results for the electric and magnetic polarizabilities of pions and nucleons. In strong constant fields, we extend the Gell-Mann-Oakes-Renner relation. For the case of electric fields, we find that non-perturbative effects result in hadron decay. For sufficiently strong magnetic fields, the chiral analysis confirms that the nucleon hierarchy becomes inverted giving rise to proton beta-decay. Properties of asymptotic expansions are explored by considering weak field limits. In the regime where the perturbative expansion breaks down, the first-order term gives the best agreement with the non perturbative result.
[ { "created": "Thu, 28 Aug 2008 18:16:46 GMT", "version": "v1" }, { "created": "Tue, 4 Nov 2008 21:12:38 GMT", "version": "v2" } ]
2008-12-18
[ [ "Tiburzi", "Brian C.", "" ] ]
We use chiral perturbation theory to investigate hadronic properties in strong electric and magnetic fields. A strong-field power counting is employed, and results for pions and nucleons are obtained using Schwinger's proper-time method. In the limit of weak fields, we accordingly recover the well known one-loop chiral perturbation theory results for the electric and magnetic polarizabilities of pions and nucleons. In strong constant fields, we extend the Gell-Mann-Oakes-Renner relation. For the case of electric fields, we find that non-perturbative effects result in hadron decay. For sufficiently strong magnetic fields, the chiral analysis confirms that the nucleon hierarchy becomes inverted giving rise to proton beta-decay. Properties of asymptotic expansions are explored by considering weak field limits. In the regime where the perturbative expansion breaks down, the first-order term gives the best agreement with the non perturbative result.
0802.2470
Jonathan Butterworth
Jonathan M. Butterworth, Adam R. Davison, Mathieu Rubin, Gavin P. Salam
Jet substructure as a new Higgs search channel at the LHC
4 pages, 3 figures
Phys.Rev.Lett.100:242001,2008
10.1103/PhysRevLett.100.242001
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is widely considered that, for Higgs boson searches at the Large Hadron Collider, WH and ZH production where the Higgs boson decays to b anti-b are poor search channels due to large backgrounds. We show that at high transverse momenta, employing state-of-the-art jet reconstruction and decomposition techniques, these processes can be recovered as promising search channels for the standard model Higgs boson around 120 GeV in mass.
[ { "created": "Mon, 18 Feb 2008 19:57:19 GMT", "version": "v1" }, { "created": "Thu, 19 Jun 2008 09:05:18 GMT", "version": "v2" } ]
2008-11-26
[ [ "Butterworth", "Jonathan M.", "" ], [ "Davison", "Adam R.", "" ], [ "Rubin", "Mathieu", "" ], [ "Salam", "Gavin P.", "" ] ]
It is widely considered that, for Higgs boson searches at the Large Hadron Collider, WH and ZH production where the Higgs boson decays to b anti-b are poor search channels due to large backgrounds. We show that at high transverse momenta, employing state-of-the-art jet reconstruction and decomposition techniques, these processes can be recovered as promising search channels for the standard model Higgs boson around 120 GeV in mass.
hep-ph/0407128
M. Benjamin Portheault
Benjamin Portheault
High Q**2 Structure Functions and Parton Distributions
null
null
10.1142/9789812702722_0001
null
hep-ph
null
This contribution reviews the main achievements in inclusive measurements made by the H1 and ZEUS collaborations during the first phase of HERA data taking. The QCD analysis of these data by both collaborations are described. The case for a common QCD analysis is briefly discussed, with an emphasis on the possible $W$ mass extraction.
[ { "created": "Sat, 10 Jul 2004 21:11:11 GMT", "version": "v1" } ]
2017-08-23
[ [ "Portheault", "Benjamin", "" ] ]
This contribution reviews the main achievements in inclusive measurements made by the H1 and ZEUS collaborations during the first phase of HERA data taking. The QCD analysis of these data by both collaborations are described. The case for a common QCD analysis is briefly discussed, with an emphasis on the possible $W$ mass extraction.
1401.3278
Bjorn Garbrecht
Bjorn Garbrecht
More Viable Parameter Space for Leptogenesis
20 pages, journal version, explanations added
Phys. Rev. D 90, 063522 (2014)
10.1103/PhysRevD.90.063522
TUM-HEP-926-14
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Lepton flavour asymmetries generated at the onset of the oscillations of sterile neutrinos with masses above the electroweak scale can be large enough to partly survive washout and to explain the baryon asymmetry of the Universe. This opens up new regions of parameter space, where Leptogenesis is viable within the type-I seesaw framework. In particular, we find it possible that the sterile neutrinos masses are substantially below 10^9 GeV, while not being degenerate. However, the required reheat temperature that is determined by the begin of the oscillations lies some orders of magnitude above the sterile neutrino mass-scale.
[ { "created": "Tue, 14 Jan 2014 18:47:09 GMT", "version": "v1" }, { "created": "Thu, 25 Sep 2014 21:15:36 GMT", "version": "v2" } ]
2014-10-01
[ [ "Garbrecht", "Bjorn", "" ] ]
Lepton flavour asymmetries generated at the onset of the oscillations of sterile neutrinos with masses above the electroweak scale can be large enough to partly survive washout and to explain the baryon asymmetry of the Universe. This opens up new regions of parameter space, where Leptogenesis is viable within the type-I seesaw framework. In particular, we find it possible that the sterile neutrinos masses are substantially below 10^9 GeV, while not being degenerate. However, the required reheat temperature that is determined by the begin of the oscillations lies some orders of magnitude above the sterile neutrino mass-scale.
hep-ph/0312273
Maarten Boonekamp
Maarten Boonekamp and Tibor Kucs
DPEMC : A Monte-Carlo for Double Diffraction
Revised version
Comput.Phys.Commun. 167 (2005) 217
10.1016/j.cpc.2005.01.002
null
hep-ph
null
We extend the POMWIG Monte Carlo generator developed by B.Cox and J.Forshaw, to include new models of central production through inclusive and exclusive Double Pomeron Exchange in proton-proton collisions. Double photon Exchange processes are described as well, both in proton-proton and heavy-ion collisions. In all contexts, various models have been implemented, allowing for comparisons and uncertainty evaluation and enabling detailed experimental simulations.
[ { "created": "Fri, 19 Dec 2003 00:00:12 GMT", "version": "v1" }, { "created": "Thu, 6 May 2004 10:42:07 GMT", "version": "v2" }, { "created": "Thu, 29 Jul 2004 18:56:50 GMT", "version": "v3" } ]
2009-11-10
[ [ "Boonekamp", "Maarten", "" ], [ "Kucs", "Tibor", "" ] ]
We extend the POMWIG Monte Carlo generator developed by B.Cox and J.Forshaw, to include new models of central production through inclusive and exclusive Double Pomeron Exchange in proton-proton collisions. Double photon Exchange processes are described as well, both in proton-proton and heavy-ion collisions. In all contexts, various models have been implemented, allowing for comparisons and uncertainty evaluation and enabling detailed experimental simulations.
2105.11114
Motohiko Yoshimura
H. Hara, A. Yoshimi, and M. Yoshimura
Parity violating magnetization at neutrino pair emission using trivalent lanthanoid ions
20 pages, 12 figures. Simulation bug corrected. Manuscript adapted to publication
null
10.1103/PhysRevD.104.115006
null
hep-ph cond-mat.mtrl-sci cond-mat.supr-con hep-ex physics.atom-ph
http://creativecommons.org/licenses/by/4.0/
A new detection method using magnetization generated at triggered radiative emission of neutrino pairs (RENP), $ |e \rangle \rightarrow | g \rangle + \gamma + \sum_{ij}\nu_i \bar{\nu}_j $ (atomic de-transition from state $|e \rangle $ to state $|g \rangle$ emitting sum of neutrino pairs $\sum_{ij}\nu_i\bar{\nu}_j$ accompanied by a photon $\gamma$), is investigated in order to determine unknown neutrino properties; absolute neutrino masses of $\nu_i$ and Majorana/Dirac distinction. Magnetization associated with RENP events has parity violating component intrinsic to weak interaction enforced by crystal field effect in solids, and greatly helps background rejection of quantum electrodynamic (QED) origin even when these backgrounds are amplified. In proposed experiments we prepare a coherently excited body of trivalent lanthanoid ions, Er$^{3+}$ (a best candidate ion so far found), doped in a transparent dielectric crystal. The magnetic moment $\mu \langle \vec{S}\cdot\vec{k} \rangle/k $ arising from generated electron spin $\vec{S}$ parallel to trigger photon direction $\vec{k}/k$ is parity odd, and is absent in QED processes. The generated magnetic field of order nano gauss is stored in crystals long after pair emission event till spin relaxation time. An improved calculation method of coherent rate and angular distribution of magnetization is developed in order to incorporate finite size effect of crystal target beyond the infinite size limit in previous calculations.
[ { "created": "Mon, 24 May 2021 06:36:19 GMT", "version": "v1" }, { "created": "Thu, 18 Nov 2021 05:54:57 GMT", "version": "v2" } ]
2021-12-22
[ [ "Hara", "H.", "" ], [ "Yoshimi", "A.", "" ], [ "Yoshimura", "M.", "" ] ]
A new detection method using magnetization generated at triggered radiative emission of neutrino pairs (RENP), $ |e \rangle \rightarrow | g \rangle + \gamma + \sum_{ij}\nu_i \bar{\nu}_j $ (atomic de-transition from state $|e \rangle $ to state $|g \rangle$ emitting sum of neutrino pairs $\sum_{ij}\nu_i\bar{\nu}_j$ accompanied by a photon $\gamma$), is investigated in order to determine unknown neutrino properties; absolute neutrino masses of $\nu_i$ and Majorana/Dirac distinction. Magnetization associated with RENP events has parity violating component intrinsic to weak interaction enforced by crystal field effect in solids, and greatly helps background rejection of quantum electrodynamic (QED) origin even when these backgrounds are amplified. In proposed experiments we prepare a coherently excited body of trivalent lanthanoid ions, Er$^{3+}$ (a best candidate ion so far found), doped in a transparent dielectric crystal. The magnetic moment $\mu \langle \vec{S}\cdot\vec{k} \rangle/k $ arising from generated electron spin $\vec{S}$ parallel to trigger photon direction $\vec{k}/k$ is parity odd, and is absent in QED processes. The generated magnetic field of order nano gauss is stored in crystals long after pair emission event till spin relaxation time. An improved calculation method of coherent rate and angular distribution of magnetization is developed in order to incorporate finite size effect of crystal target beyond the infinite size limit in previous calculations.
hep-ph/0201299
Nikolai Achasov
N.N. Achasov
Radiative decays of \phi-meson and nature of light scalar resonances
12 pages, 5 figures, revtex
null
10.1016/j.nuclphysa.2003.09.002
null
hep-ph hep-ex nucl-th
null
Based on gauge invariance, we show that the new threshold phenomenon is discovered in the \phi radiative decays \phi\to\gamma a0\to\gamma\pi0\eta and \phi\to\gamma f0\to\gamma\pi0\pi0. This enables to conclude that production of the lightest scalar mesons a0(980) and f0(980) in these decays is caused by the four-quark transitions, resulting in strong restrictions on the large Nc expansions of the decay amplitudes. The analysis shows that these constraints give new evidences in favor of the four-quark nature of a0(980) and f0(980) mesons.
[ { "created": "Thu, 31 Jan 2002 03:42:10 GMT", "version": "v1" } ]
2016-09-21
[ [ "Achasov", "N. N.", "" ] ]
Based on gauge invariance, we show that the new threshold phenomenon is discovered in the \phi radiative decays \phi\to\gamma a0\to\gamma\pi0\eta and \phi\to\gamma f0\to\gamma\pi0\pi0. This enables to conclude that production of the lightest scalar mesons a0(980) and f0(980) in these decays is caused by the four-quark transitions, resulting in strong restrictions on the large Nc expansions of the decay amplitudes. The analysis shows that these constraints give new evidences in favor of the four-quark nature of a0(980) and f0(980) mesons.
1805.05219
Elena Petreska
Dani\"el Boer, Tom van Daal, Piet J. Mulders and Elena Petreska
Directed flow from C-odd gluon correlations at small $x$
23 pages, 3 figures. v2: References added; Added plot for A=63 in Fig.3 and a discussion on the A dependence. Version accepted for publication in JHEP
null
10.1007/JHEP07(2018)140
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is shown that odd harmonic azimuthal correlations, including the directed flow $v_1$, in forward two-particle production in peripheral proton-nucleus ($pA$) collisions can arise simply from the radial nuclear profile of a large nucleus. This requires consideration of the C-odd part of the gluonic generalized transverse momentum dependent (GTMD) correlator of nucleons in the nucleus. The gluonic GTMD correlator is the Fourier transform of an off-forward hadronic matrix element containing gluonic field strength tensors that are connected by gauge links. It is parametrized in terms of various gluon GTMD distribution functions (GTMDs). We show (in a gauge invariant way) that for the relevant dipole-type gauge link structure in the small-$x$ limit the GTMD correlator reduces to a generalized Wilson loop correlator. The Wilson loop correlator is parametrized in terms of a single function, implying that in the region of small $x$ there is only one independent dipole-type GTMD, which can have a C-odd part. We show that the odderon Wigner distribution, which is related to this C-odd dipole GTMD by a Fourier transform, generates odd harmonics in the two-particle azimuthal correlations in peripheral $pA$ collisions. We calculate the first odd harmonic $v_1$ for forward production within the color glass condensate framework in the limit of a large number of colors. We find that nonzero odd harmonics are present without breaking the rotational symmetry of the nucleus, arising just from its inhomogeneity in the radial direction. Using a CGC model with a cubic action, we illustrate that percent level $v_1$ can arise from this C-odd mechanism. In contrast, we show that only even harmonics arise in diffractive dijet production in ultra-peripheral $pA$ collisions where this gluon dipole GTMD also appears.
[ { "created": "Mon, 14 May 2018 15:11:54 GMT", "version": "v1" }, { "created": "Wed, 25 Jul 2018 20:23:04 GMT", "version": "v2" } ]
2018-08-15
[ [ "Boer", "Daniël", "" ], [ "van Daal", "Tom", "" ], [ "Mulders", "Piet J.", "" ], [ "Petreska", "Elena", "" ] ]
It is shown that odd harmonic azimuthal correlations, including the directed flow $v_1$, in forward two-particle production in peripheral proton-nucleus ($pA$) collisions can arise simply from the radial nuclear profile of a large nucleus. This requires consideration of the C-odd part of the gluonic generalized transverse momentum dependent (GTMD) correlator of nucleons in the nucleus. The gluonic GTMD correlator is the Fourier transform of an off-forward hadronic matrix element containing gluonic field strength tensors that are connected by gauge links. It is parametrized in terms of various gluon GTMD distribution functions (GTMDs). We show (in a gauge invariant way) that for the relevant dipole-type gauge link structure in the small-$x$ limit the GTMD correlator reduces to a generalized Wilson loop correlator. The Wilson loop correlator is parametrized in terms of a single function, implying that in the region of small $x$ there is only one independent dipole-type GTMD, which can have a C-odd part. We show that the odderon Wigner distribution, which is related to this C-odd dipole GTMD by a Fourier transform, generates odd harmonics in the two-particle azimuthal correlations in peripheral $pA$ collisions. We calculate the first odd harmonic $v_1$ for forward production within the color glass condensate framework in the limit of a large number of colors. We find that nonzero odd harmonics are present without breaking the rotational symmetry of the nucleus, arising just from its inhomogeneity in the radial direction. Using a CGC model with a cubic action, we illustrate that percent level $v_1$ can arise from this C-odd mechanism. In contrast, we show that only even harmonics arise in diffractive dijet production in ultra-peripheral $pA$ collisions where this gluon dipole GTMD also appears.
1404.4281
Nobuhito Maru
Yuki Adachi, Nobuaki Kurahashi and Nobuhito Maru
mu to 3e and mu to e Conversion in Gauge-Higgs Unification
17 pages, 3 figures
null
null
OCU-PHYS 394
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The two dominant processes of lepton flavor violation, mu to 3e and mu to e conversion in atomic nuclei caused by neutral KK gauge boson exchanges at tree level, are studied in the context of five dimensional gauge-Higgs unification scenario. The key point of the flavor violation is a fact that the bulk masses and the brane ones cannot be simultaneously diagonalized. We estimate the branching ratio of each processes and obtain the lower bound of compactification scale around weak scale from the current experimental data. We discuss the reasons why the final result is not so severe although the large mixing in the lepton sector seems to give large lepton flavor violation processes.
[ { "created": "Wed, 16 Apr 2014 15:19:31 GMT", "version": "v1" } ]
2014-04-17
[ [ "Adachi", "Yuki", "" ], [ "Kurahashi", "Nobuaki", "" ], [ "Maru", "Nobuhito", "" ] ]
The two dominant processes of lepton flavor violation, mu to 3e and mu to e conversion in atomic nuclei caused by neutral KK gauge boson exchanges at tree level, are studied in the context of five dimensional gauge-Higgs unification scenario. The key point of the flavor violation is a fact that the bulk masses and the brane ones cannot be simultaneously diagonalized. We estimate the branching ratio of each processes and obtain the lower bound of compactification scale around weak scale from the current experimental data. We discuss the reasons why the final result is not so severe although the large mixing in the lepton sector seems to give large lepton flavor violation processes.
hep-ph/0101121
Gino Isidori
Gino Isidori
Supersymmetric effects in rare semileptonic decays of B and K mesons
15 pages, Latex, invited talk at RADCOR 2000 (Carmel CA, USA, Sept. 2000)
null
null
CERN-TH/2001-003
hep-ph
null
Rare flavour-changing neutral-current transitions of the type $s \to d \ell^+\ell^-(\nu\bar\nu)$ and $b \to s \ell^+\ell^-(\nu\bar\nu)$ are analysed in supersymmetric extensions of the Standard Model with generic flavour couplings. It is shown that these processes are particularly sensitive to the left--right mixing of the squarks and that, in the presence of non-universal $A$ terms, they could lead to unambiguous signatures of new physics in exclusive $K$ and $B$ meson decays.
[ { "created": "Thu, 11 Jan 2001 18:49:13 GMT", "version": "v1" } ]
2007-05-23
[ [ "Isidori", "Gino", "" ] ]
Rare flavour-changing neutral-current transitions of the type $s \to d \ell^+\ell^-(\nu\bar\nu)$ and $b \to s \ell^+\ell^-(\nu\bar\nu)$ are analysed in supersymmetric extensions of the Standard Model with generic flavour couplings. It is shown that these processes are particularly sensitive to the left--right mixing of the squarks and that, in the presence of non-universal $A$ terms, they could lead to unambiguous signatures of new physics in exclusive $K$ and $B$ meson decays.
hep-ph/0202143
Tomoharu Suzuki
Naoyuki Haba and Tomoharu Suzuki
The neutrinoless double $\beta$ decay and the neutrino mass hierarchy
12 pages, 7 figures, LaTeX
Mod.Phys.Lett. A17 (2002) 865-874
10.1142/S0217732302007156
DPNU-02-03
hep-ph
null
Recently the evidence of the neutrinoless double $\beta$ ($0\nu \beta\beta$) decay has been announced. This means that neutrinos are Majorana particles and their mass hierarchy is forced to certain patterns in the diagonal basis of charged lepton mass matrix. We estimate the magnitude of $0\nu \beta\beta$ decay in the classification of the neutrino mass hierarchy patterns as Type A, $m_{1,2} \ll m_{3}$, Type B, $m_1 \sim m_2 \gg m_3$, and Type C, $m_1 \sim m_2 \sim m_3$, where $m_{i}$ is the $i$-th generation neutrino absolute mass. The data of $0\nu \beta\beta$ decay experiment suggests the neutrino mass hierarchy pattern should be Type B or C. Type B predicts a small magnitude of $0\nu \beta\beta$ decay which is just edge of the allowed region of experimental value in $95% \mathrm{c.l.}$, where Majorana CP phases should be in a certain parameter region. Type C can induce the suitably large amount of $0\nu \beta\beta$ decay which is consistent with the experimental data, where overall scale of degenerate neutrino mass plays a crucial role, and its large value can induce the large $0\nu \beta\beta$ decay in any parameter regions of Majorana CP phases.
[ { "created": "Fri, 15 Feb 2002 06:54:33 GMT", "version": "v1" } ]
2016-12-21
[ [ "Haba", "Naoyuki", "" ], [ "Suzuki", "Tomoharu", "" ] ]
Recently the evidence of the neutrinoless double $\beta$ ($0\nu \beta\beta$) decay has been announced. This means that neutrinos are Majorana particles and their mass hierarchy is forced to certain patterns in the diagonal basis of charged lepton mass matrix. We estimate the magnitude of $0\nu \beta\beta$ decay in the classification of the neutrino mass hierarchy patterns as Type A, $m_{1,2} \ll m_{3}$, Type B, $m_1 \sim m_2 \gg m_3$, and Type C, $m_1 \sim m_2 \sim m_3$, where $m_{i}$ is the $i$-th generation neutrino absolute mass. The data of $0\nu \beta\beta$ decay experiment suggests the neutrino mass hierarchy pattern should be Type B or C. Type B predicts a small magnitude of $0\nu \beta\beta$ decay which is just edge of the allowed region of experimental value in $95% \mathrm{c.l.}$, where Majorana CP phases should be in a certain parameter region. Type C can induce the suitably large amount of $0\nu \beta\beta$ decay which is consistent with the experimental data, where overall scale of degenerate neutrino mass plays a crucial role, and its large value can induce the large $0\nu \beta\beta$ decay in any parameter regions of Majorana CP phases.
hep-ph/9411430
Karl Westerberg
Karl M. Westerberg
Kaon Condensation in the Bound-State Approach to the Skyrme Model
LaTeX format, 15 pages. 3 Postscript figures, compressed and uuencoded
Phys. Rev. D 51, 5030 (1995)
10.1103/PhysRevD.51.5030
PUPT-1521
hep-ph
null
We explore kaon condensation using the bound-state approach to the Skyrme model on a 3-sphere. The condensation occurs when the energy required to produce a $K^-$ falls below the electron fermi level. This happens at the baryon number density on the order of 3--4 times nuclear density.
[ { "created": "Wed, 30 Nov 1994 00:52:01 GMT", "version": "v1" } ]
2016-08-24
[ [ "Westerberg", "Karl M.", "" ] ]
We explore kaon condensation using the bound-state approach to the Skyrme model on a 3-sphere. The condensation occurs when the energy required to produce a $K^-$ falls below the electron fermi level. This happens at the baryon number density on the order of 3--4 times nuclear density.
0907.1944
C. A. Dominguez
C.A. Dominguez, H. Falomir, M. Ipinza, S. Kohler, M. Loewe, J.C. Rojas
QED vacuum fluctuations and induced electric dipole moment of the neutron
A misprint has been corrected, and three new references have been added
Phys.Rev.D80:033008,2009
10.1103/PhysRevD.80.033008
UCT-TP-276/09
hep-ph hep-ex hep-lat hep-th nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Quantum fluctuations in the QED vacuum generate non-linear effects, such as peculiar induced electromagnetic fields. In particular, we show here that an electrically neutral particle, possessing a magnetic dipole moment, develops an induced electric dipole-type moment with unusual angular dependence, when immersed in a quasistatic, constant external electric field. The calculation of this effect is done in the framework of the Euler-Heisenberg effective QED Lagrangian, corresponding to the weak field asymptotic expansion of the effective action to one-loop order. It is argued that the neutron might be a good candidate to probe this signal of non-linearity in QED.
[ { "created": "Mon, 13 Jul 2009 11:54:23 GMT", "version": "v1" }, { "created": "Wed, 5 Aug 2009 14:35:32 GMT", "version": "v2" } ]
2009-09-01
[ [ "Dominguez", "C. A.", "" ], [ "Falomir", "H.", "" ], [ "Ipinza", "M.", "" ], [ "Kohler", "S.", "" ], [ "Loewe", "M.", "" ], [ "Rojas", "J. C.", "" ] ]
Quantum fluctuations in the QED vacuum generate non-linear effects, such as peculiar induced electromagnetic fields. In particular, we show here that an electrically neutral particle, possessing a magnetic dipole moment, develops an induced electric dipole-type moment with unusual angular dependence, when immersed in a quasistatic, constant external electric field. The calculation of this effect is done in the framework of the Euler-Heisenberg effective QED Lagrangian, corresponding to the weak field asymptotic expansion of the effective action to one-loop order. It is argued that the neutron might be a good candidate to probe this signal of non-linearity in QED.
0811.2671
Kazem Azizi
K. Azizi, R. Khosravi, F. Falahati
Analysis of the $B_q\to D_q(D_q^*) P$ and $B_q\to D_q(D_q^*) V$ decays within the factorization approach in QCD
18 Pages and 9 Tables
Int.J.Mod.Phys.A24:5845-5860,2009
10.1142/S0217751X0904751X
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Using the factorization approach and considering the contributions of the current-current, QCD penguin and electroweak penguin operators at the leading approximation, the decay amplitudes and decay widths of $B_q\to D_q(D_q^*) P$ and $B_q\to D_q(D_q^*) V$ transitions, where $q=u,d,s$ and P and V are pseudoscalar and vector mesons, are calculated in terms of the transition form factors of the $B_q\to D_{q}$ and $B_q\to D^{*}_{q}$. Having computed those form factors in three-point QCD sum rules, the branching fraction for these decays are also evaluated. A comparison of our results with the predictions of the perturbative QCD as well as the existing experimental data is presented.
[ { "created": "Mon, 17 Nov 2008 11:09:01 GMT", "version": "v1" }, { "created": "Tue, 18 Aug 2009 15:02:04 GMT", "version": "v2" }, { "created": "Thu, 17 Dec 2009 14:16:29 GMT", "version": "v3" } ]
2010-02-01
[ [ "Azizi", "K.", "" ], [ "Khosravi", "R.", "" ], [ "Falahati", "F.", "" ] ]
Using the factorization approach and considering the contributions of the current-current, QCD penguin and electroweak penguin operators at the leading approximation, the decay amplitudes and decay widths of $B_q\to D_q(D_q^*) P$ and $B_q\to D_q(D_q^*) V$ transitions, where $q=u,d,s$ and P and V are pseudoscalar and vector mesons, are calculated in terms of the transition form factors of the $B_q\to D_{q}$ and $B_q\to D^{*}_{q}$. Having computed those form factors in three-point QCD sum rules, the branching fraction for these decays are also evaluated. A comparison of our results with the predictions of the perturbative QCD as well as the existing experimental data is presented.
2003.10833
Qin Chang
Qin Chang, Xiao-Lin Wang and Li-Ting Wang
Tensor form factors of $P\to P,\,S,\,V$ and $A$ transitions within the standard and the covariant light-front approaches
34 pages, 9 figures and 7 tables. arXiv admin note: text overlap with arXiv:1908.04677
Chin.Phys. C44 (2019) no.8, 083105
10.1088/1674-1137/44/8/083105
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper, we investigate the tensor form factors of $P\to P,\,S,\,V$ and $A$ transitions within the standard light-front (SLF) and the covariant light-front (CLF) quark models (QMs). The self-consistency and Lorentz covariance of CLF QM are analyzed via these quantities, and the effects of zero-mode are discussed. For the $P\to V$ and $A$ transitions, besides the inconsistence between the results extracted via longitudinal and transverse polarization states, which is caused by the residual $\omega$-dependent spurious contributions, we find and analyze a "new" self-consistence problem of the traditional CLF QM, which is caused by the different strategies for dealing deal with the trace term in CLF matrix element. A possible solution to the problems of traditional CLF QM is discussed and confirmed numerically. Finally, the theoretical predictions for the tensor form factors of some $c\to q,\,s$ and $b\to q,\,s\,,c$ ($q=u,d$) induced $P\to P,\,S,\,V$ and $A$ transitions are updated within the CLF QM with a self-consistent scheme.
[ { "created": "Sat, 21 Mar 2020 03:49:57 GMT", "version": "v1" } ]
2020-07-27
[ [ "Chang", "Qin", "" ], [ "Wang", "Xiao-Lin", "" ], [ "Wang", "Li-Ting", "" ] ]
In this paper, we investigate the tensor form factors of $P\to P,\,S,\,V$ and $A$ transitions within the standard light-front (SLF) and the covariant light-front (CLF) quark models (QMs). The self-consistency and Lorentz covariance of CLF QM are analyzed via these quantities, and the effects of zero-mode are discussed. For the $P\to V$ and $A$ transitions, besides the inconsistence between the results extracted via longitudinal and transverse polarization states, which is caused by the residual $\omega$-dependent spurious contributions, we find and analyze a "new" self-consistence problem of the traditional CLF QM, which is caused by the different strategies for dealing deal with the trace term in CLF matrix element. A possible solution to the problems of traditional CLF QM is discussed and confirmed numerically. Finally, the theoretical predictions for the tensor form factors of some $c\to q,\,s$ and $b\to q,\,s\,,c$ ($q=u,d$) induced $P\to P,\,S,\,V$ and $A$ transitions are updated within the CLF QM with a self-consistent scheme.
0909.3957
Jusak Tandean
Jusak Tandean
Probing New Physics in Charm Couplings with Kaon and Other Hadron Processes
6 pages, 1 figure; talk given at 2009 KAON International Conference, 9-12 June 2009, Tsukuba, Japan
PoS KAON2009:011,2009
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is possible that the low-energy effects of physics beyond the standard model can be parametrized mainly by anomalous couplings of quarks to the W boson. Such couplings can generate potentially significant contributions to various transitions that can be probed by current and future experiments. This work explores constraints on anomalous charm-W couplings from a number of CP-conserving and -violating processes involving the kaon and other flavored hadrons.
[ { "created": "Tue, 22 Sep 2009 11:00:58 GMT", "version": "v1" } ]
2010-04-23
[ [ "Tandean", "Jusak", "" ] ]
It is possible that the low-energy effects of physics beyond the standard model can be parametrized mainly by anomalous couplings of quarks to the W boson. Such couplings can generate potentially significant contributions to various transitions that can be probed by current and future experiments. This work explores constraints on anomalous charm-W couplings from a number of CP-conserving and -violating processes involving the kaon and other flavored hadrons.
2303.14192
Takuya Hirose
Takuya Hirose, Hiroto Shibuya
Relation between higher-dimensional gauge theories and gravitational waves from first-order phase transitions
17 pages, 6 figures, 1 table
null
null
KANAZAWA-23-05, NITEP 169
hep-ph gr-qc
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work, we investigate the relation between higher-dimensional gauge theories and stochastic gravitational wave (GW) spectrums caused by their potential. It is known that the higher-dimensional gauge theories can induce the spontaneous symmetry breaking of the gauge symmetry. If the spontaneous symmetry breaking induces the first-order phase transition, the stochastic GW can be observed in future interferometers. Through our numerical calculations, we reveal that distinctive parameters in the theories, like the compact scale, can change the GW spectrums dynamically. We also discuss the verifiability of the theories through the GW observations.
[ { "created": "Thu, 23 Mar 2023 10:15:50 GMT", "version": "v1" }, { "created": "Mon, 11 Dec 2023 11:08:22 GMT", "version": "v2" } ]
2023-12-12
[ [ "Hirose", "Takuya", "" ], [ "Shibuya", "Hiroto", "" ] ]
In this work, we investigate the relation between higher-dimensional gauge theories and stochastic gravitational wave (GW) spectrums caused by their potential. It is known that the higher-dimensional gauge theories can induce the spontaneous symmetry breaking of the gauge symmetry. If the spontaneous symmetry breaking induces the first-order phase transition, the stochastic GW can be observed in future interferometers. Through our numerical calculations, we reveal that distinctive parameters in the theories, like the compact scale, can change the GW spectrums dynamically. We also discuss the verifiability of the theories through the GW observations.
1508.02891
Eibun Senaha
Cheng-Wei Chiang, Eibun Senaha
Electroweak interacting dark matter with a singlet scalar portal
17 pages, 6 figures. v2: references added; v3: references added, version to appear in Phys.Lett.B
null
10.1016/j.physletb.2015.09.011
IPMU15-0134
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate an electroweak interacting dark matter (DM) model in which the DM is the neutral component of the SU$(2)_L$ triplet fermion that couples to the standard model (SM) Higgs sector via an SM singlet Higgs boson. In this setup, the DM can have a CP-violating coupling to the singlet Higgs boson at the renormalizable level. As long as the nonzero Higgs portal coupling (singlet-doublet Higgs boson mixing) exists, we can probe CP violation of the DM via the electric dipole moment of the electron. Assuming the $\mathcal{O}(1)$ CP-violating phase in magnitude, we investigate the relationship between the electron EDM and the singlet-like Higgs boson mass and coupling. It is found that for moderate values of the Higgs portal couplings, current experimental EDM bound is not able to exclude the wide parameter space due to a cancellation mechanism at work. We also study the spin-independent cross section of the DM in this model. It is found that although a similar cancellation mechanism may diminish the leading-order correction, as often occurs in the ordinary Higgs portal DM scenarios, the residual higher-order effects leave an $\mathcal{O}(10^{-47})~{\rm cm}^2$ correction in the cancellation region. It is shown that our benchmark scenarios would be fully tested by combining all future experiments of the electron EDM, DM direct detection and Higgs physics.
[ { "created": "Wed, 12 Aug 2015 12:27:03 GMT", "version": "v1" }, { "created": "Thu, 20 Aug 2015 17:43:14 GMT", "version": "v2" }, { "created": "Fri, 4 Sep 2015 02:45:32 GMT", "version": "v3" } ]
2015-09-16
[ [ "Chiang", "Cheng-Wei", "" ], [ "Senaha", "Eibun", "" ] ]
We investigate an electroweak interacting dark matter (DM) model in which the DM is the neutral component of the SU$(2)_L$ triplet fermion that couples to the standard model (SM) Higgs sector via an SM singlet Higgs boson. In this setup, the DM can have a CP-violating coupling to the singlet Higgs boson at the renormalizable level. As long as the nonzero Higgs portal coupling (singlet-doublet Higgs boson mixing) exists, we can probe CP violation of the DM via the electric dipole moment of the electron. Assuming the $\mathcal{O}(1)$ CP-violating phase in magnitude, we investigate the relationship between the electron EDM and the singlet-like Higgs boson mass and coupling. It is found that for moderate values of the Higgs portal couplings, current experimental EDM bound is not able to exclude the wide parameter space due to a cancellation mechanism at work. We also study the spin-independent cross section of the DM in this model. It is found that although a similar cancellation mechanism may diminish the leading-order correction, as often occurs in the ordinary Higgs portal DM scenarios, the residual higher-order effects leave an $\mathcal{O}(10^{-47})~{\rm cm}^2$ correction in the cancellation region. It is shown that our benchmark scenarios would be fully tested by combining all future experiments of the electron EDM, DM direct detection and Higgs physics.
1102.3258
Andrei Leonidov
M.Yu. Azarkin, I.M. Dremin, A.V. Leonidov
Soft ridge in proton-proton collisions
null
Mod.Phys.Lett.A26:963-966,2011; Erratum-ibid.A26:1309,2011
10.1142/S0217732311035468 10.1142/S0217732311036012
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
It is shown that the soft mechanism of multiparticle production by Lund hadronic strings formed by colliding constituent degrees of freedom generates a shape of angular correlations similar to the ridge structure observed in the pp collisions at 7 TeV at the LHC.
[ { "created": "Wed, 16 Feb 2011 07:52:39 GMT", "version": "v1" } ]
2011-06-28
[ [ "Azarkin", "M. Yu.", "" ], [ "Dremin", "I. M.", "" ], [ "Leonidov", "A. V.", "" ] ]
It is shown that the soft mechanism of multiparticle production by Lund hadronic strings formed by colliding constituent degrees of freedom generates a shape of angular correlations similar to the ridge structure observed in the pp collisions at 7 TeV at the LHC.
2104.13442
Miguel G. Folgado
Miguel G. Folgado
Dark Matter Phenomenology: Sterile Neutrino Portal and Gravitational Portal in Extra-Dimensions
208 pages. Thesis defended on March 31st, 2021. Full academic version can be found in the following repository: https://roderic.uv.es/handle/10550/78343
null
null
null
hep-ph astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The Standard Model of Fundamental Interactions (SM) represents one of the most precise theories in physics. Among the predictions of the SM we find, for instance, the anomalous magnetic moment of the electron $a_e = 0.001159652181643(764)$. This prediction agrees with the experimental results to more than ten significant digits, the most accurate prediction in the history of physics. However, nowadays we have several evidences that the SM only explains $5 \%$ of the matter content of the Universe. The other $95 \%$ are composed by the so-called Dark Energy and Dark Matter. As their names suggest, the nature of these two components of the energy/matter content of the Universe is still unclear and represents one of the most important challenges for the particle physicists. In this Thesis we have focused in the study of the phenomenology of one of these mysterious components of the Universe, the Dark Matter. Although we have many evidences of its existence, this new type of matter has not been detected yet. As a consequence, the landscape of the models that can explain the Dark Matter properties is huge. In the present work we propose and study several Dark Matter models, setting limits by using experimental results.
[ { "created": "Tue, 27 Apr 2021 19:34:05 GMT", "version": "v1" } ]
2021-04-29
[ [ "Folgado", "Miguel G.", "" ] ]
The Standard Model of Fundamental Interactions (SM) represents one of the most precise theories in physics. Among the predictions of the SM we find, for instance, the anomalous magnetic moment of the electron $a_e = 0.001159652181643(764)$. This prediction agrees with the experimental results to more than ten significant digits, the most accurate prediction in the history of physics. However, nowadays we have several evidences that the SM only explains $5 \%$ of the matter content of the Universe. The other $95 \%$ are composed by the so-called Dark Energy and Dark Matter. As their names suggest, the nature of these two components of the energy/matter content of the Universe is still unclear and represents one of the most important challenges for the particle physicists. In this Thesis we have focused in the study of the phenomenology of one of these mysterious components of the Universe, the Dark Matter. Although we have many evidences of its existence, this new type of matter has not been detected yet. As a consequence, the landscape of the models that can explain the Dark Matter properties is huge. In the present work we propose and study several Dark Matter models, setting limits by using experimental results.
1810.07659
Qing-Hong Cao
Qing-Hong Cao, Gang Li, Ke-Pan Xie, Jue Zhang
Searching for weak singlet charged scalar at lepton colliders
null
Phys. Rev. D 99, 015027 (2019)
10.1103/PhysRevD.99.015027
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A weak singlet charged scalar exists in many new physics models beyond the Standard Model. The discovery potential of the singlet charged scalar is explored at future lepton colliders, e.g. the CEPC, ILC-350 and ILC-500. We demonstrate that one can discover the singlet charged scalar up to 118 GeV at the CEPC with an integrated luminosity of $5~\mathrm{ab}^{-1}$. At the ILC-350 and the ILC-500 with an integrated luminosity of $1~\mathrm{ab}^{-1}$ such a discovery limit can be further improved to 136 GeV and 160 GeV, respectively.
[ { "created": "Wed, 17 Oct 2018 16:43:49 GMT", "version": "v1" } ]
2019-02-06
[ [ "Cao", "Qing-Hong", "" ], [ "Li", "Gang", "" ], [ "Xie", "Ke-Pan", "" ], [ "Zhang", "Jue", "" ] ]
A weak singlet charged scalar exists in many new physics models beyond the Standard Model. The discovery potential of the singlet charged scalar is explored at future lepton colliders, e.g. the CEPC, ILC-350 and ILC-500. We demonstrate that one can discover the singlet charged scalar up to 118 GeV at the CEPC with an integrated luminosity of $5~\mathrm{ab}^{-1}$. At the ILC-350 and the ILC-500 with an integrated luminosity of $1~\mathrm{ab}^{-1}$ such a discovery limit can be further improved to 136 GeV and 160 GeV, respectively.
hep-ph/0407340
Oliver Brein
Oliver Brein
Adaptive scanning - a proposal how to scan theoretical predictions over a multi-dimensional parameter space efficiently
8 pages, 4 figures
Comput.Phys.Commun. 170 (2005) 42-48
10.1016/j.cpc.2005.03.104
PITHA-04-12
hep-ph
null
A method is presented to exploit adaptive integration algorithms using importance sampling, like VEGAS, for the task of scanning theoretical predictions depending on a multi-dimensional parameter space. Usually, a parameter scan is performed with emphasis on certain features of a theoretical prediction. Adaptive integration algorithms are well-suited to perform this task very efficiently. Predictions which depend on parameter spaces with many dimensions call for such an adaptive scanning algorithm.
[ { "created": "Thu, 29 Jul 2004 13:09:56 GMT", "version": "v1" } ]
2010-04-05
[ [ "Brein", "Oliver", "" ] ]
A method is presented to exploit adaptive integration algorithms using importance sampling, like VEGAS, for the task of scanning theoretical predictions depending on a multi-dimensional parameter space. Usually, a parameter scan is performed with emphasis on certain features of a theoretical prediction. Adaptive integration algorithms are well-suited to perform this task very efficiently. Predictions which depend on parameter spaces with many dimensions call for such an adaptive scanning algorithm.
hep-ph/9504266
null
T.S.Evans
Thermal Green Functions at Zero Energy
16 pages, LaTeX (no figures), available through anonymous ftp as LaTeX from ftp://euclid.tp.ph.ic.ac.uk/papers/94-5_26.tex or as LaTeX or postscript at http://euclid.tp.ph.ic.ac.uk/Papers/index.html
Nucl.Phys. B496 (1997) 486-502
10.1016/S0550-3213(97)00272-1
Imperial/TP/94-95/26
hep-ph
null
The thermal expectation values of all possible bosonic generalised retarded functions evaluated at zero energy are studied. The relationship of such functions to calculational schemes, technical problems and physical applications is outlined. It is then shown that all generalised retarded functions constructed from any one set of bosonic fields are equal at zero energy. This is done completely generally and is not limited to any approximation scheme such as perturbation theory.
[ { "created": "Mon, 10 Apr 1995 11:37:13 GMT", "version": "v1" } ]
2009-10-28
[ [ "Evans", "T. S.", "" ] ]
The thermal expectation values of all possible bosonic generalised retarded functions evaluated at zero energy are studied. The relationship of such functions to calculational schemes, technical problems and physical applications is outlined. It is then shown that all generalised retarded functions constructed from any one set of bosonic fields are equal at zero energy. This is done completely generally and is not limited to any approximation scheme such as perturbation theory.
hep-ph/0312385
Seong Chan Park
Daisuke Ida (Tokyo Inst. Tech.), Kin-ya Oda (Munich, Tech. U.) and Seong Chan Park (Korea Inst. Advanced Study)
Rotating Black Holes at Future Colliders
4 pages, Talk presented at the 6th RESCEU International Symposium, Fontier in Astroparticle Physics and Cosmology, 4 - 7 November 2003, The University of Tokyo, Tokyo, Japan. To appear in the proceeding
null
null
null
hep-ph
null
We consider the production and decay of TeV-scale black holes. Evaluation of the production cross section of higher dimensional rotating black holes is made. The master field equation for general spin-$s$ fields confined on brane world is derived. For five-dimensional (Randall-Sundrum) black holes, we obtain analytic formulae for the greybody factors in low frequency expansion.
[ { "created": "Wed, 31 Dec 2003 14:03:03 GMT", "version": "v1" }, { "created": "Mon, 5 Jan 2004 00:59:42 GMT", "version": "v2" } ]
2007-05-23
[ [ "Ida", "Daisuke", "", "Tokyo Inst. Tech." ], [ "Oda", "Kin-ya", "", "Munich, Tech. U." ], [ "Park", "Seong Chan", "", "Korea Inst. Advanced Study" ] ]
We consider the production and decay of TeV-scale black holes. Evaluation of the production cross section of higher dimensional rotating black holes is made. The master field equation for general spin-$s$ fields confined on brane world is derived. For five-dimensional (Randall-Sundrum) black holes, we obtain analytic formulae for the greybody factors in low frequency expansion.
0809.3883
Arkadii Kozhevnikov
N.N.Achasov, A.A.Kozhevnikov
Hidden local symmetry and the reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- at energies \sqrt{s}\leq 1 GeV
9 pages, 3 figures, 2 tables; accepted for publication in European Phys. Journal A
Eur.Phys.J.A38:61-69,2008
10.1140/epja/i2008-10654-x
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Based on the generalized hidden local symmetry as the chiral model of pseudoscalar, vector, and axial vector mesons, the excitation curve of the reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- is calculated for energies in the interval 0.65\leq \sqrt{s}\leq1 GeV. The theoretical predictions are compared to available data of CMD-2 and BaBaR. It is shown that the inclusion of heavy isovector resonances \rho(1450) and \rho(1700) is necessary for reconciling calculations with the data. It is found that at \sqrt{s}\approx1 GeV the contributions of the above resonances are much larger, by the factor of 30, than the \rho(770) one, and are amount to a considerable fraction \sim0.3-0.6 of the latter at \sqrt{s}\sim m_\rho.
[ { "created": "Tue, 23 Sep 2008 10:41:20 GMT", "version": "v1" } ]
2009-01-06
[ [ "Achasov", "N. N.", "" ], [ "Kozhevnikov", "A. A.", "" ] ]
Based on the generalized hidden local symmetry as the chiral model of pseudoscalar, vector, and axial vector mesons, the excitation curve of the reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- is calculated for energies in the interval 0.65\leq \sqrt{s}\leq1 GeV. The theoretical predictions are compared to available data of CMD-2 and BaBaR. It is shown that the inclusion of heavy isovector resonances \rho(1450) and \rho(1700) is necessary for reconciling calculations with the data. It is found that at \sqrt{s}\approx1 GeV the contributions of the above resonances are much larger, by the factor of 30, than the \rho(770) one, and are amount to a considerable fraction \sim0.3-0.6 of the latter at \sqrt{s}\sim m_\rho.
1106.6208
Martin Spinrath
Maurizio Monaco and Martin Spinrath
b-tau Yukawa (Non-)Unification in the CMSSM
4 pages, 1 figure
Phys.Rev.D84:055009,2011
10.1103/PhysRevD.84.055009
SISSA 33/2011/EP
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Supersymmetric Grand Unification usually provides unification of the bottom quark and the tau lepton Yukawa couplings at the GUT scale. In the CMSSM this can be realised only for a very particular choice of parameters. In this letter we study the GUT scale ratio y_tau/y_b for less peculiar parameters in the large tan beta regime and identify one parameter region preferred by current experimental data. In this region, which is well within the reach of the LHC, the ratio is very close to the recently proposed value of 3/2.
[ { "created": "Thu, 30 Jun 2011 12:46:59 GMT", "version": "v1" } ]
2011-09-13
[ [ "Monaco", "Maurizio", "" ], [ "Spinrath", "Martin", "" ] ]
Supersymmetric Grand Unification usually provides unification of the bottom quark and the tau lepton Yukawa couplings at the GUT scale. In the CMSSM this can be realised only for a very particular choice of parameters. In this letter we study the GUT scale ratio y_tau/y_b for less peculiar parameters in the large tan beta regime and identify one parameter region preferred by current experimental data. In this region, which is well within the reach of the LHC, the ratio is very close to the recently proposed value of 3/2.
hep-ph/9705256
Vladimir A. Saleev
V.A.Saleev
The bottom baryon pair production in the e^+e^- annihilation
LaTeX, 8 pages, 3 figures using psfig.sty
null
null
SSU-HEP-97/2
hep-ph
null
In the framework of the nonrelativistic diquark model of the heavy baryons and the perturbative approach of QCD we predict the value and energy dependence for the total cross section of the Lambda_b- and Sigma_b^* -baryons pair production at the energy range of the KEKB and PEP-II e^+e^- colliders.
[ { "created": "Wed, 7 May 1997 12:00:28 GMT", "version": "v1" } ]
2007-05-23
[ [ "Saleev", "V. A.", "" ] ]
In the framework of the nonrelativistic diquark model of the heavy baryons and the perturbative approach of QCD we predict the value and energy dependence for the total cross section of the Lambda_b- and Sigma_b^* -baryons pair production at the energy range of the KEKB and PEP-II e^+e^- colliders.
hep-ph/0003144
Holger Gies
Holger Gies and Rashid Shaisultanov (Tubingen U.)
Axial vector current in an electromagnetic field and low-energy neutrino-photon interactions
6 pages, references updated, final version to appear in Phys. Rev. D
Phys.Rev. D62 (2000) 073003
10.1103/PhysRevD.62.073003
null
hep-ph hep-th
null
An expression for the axial vector current in a strong, slowly varying electromagnetic field is obtained. We apply this expression to the construction of the effective action for low-energy neutrino-photon interactions.
[ { "created": "Wed, 15 Mar 2000 10:01:38 GMT", "version": "v1" }, { "created": "Wed, 19 Jul 2000 16:07:55 GMT", "version": "v2" } ]
2009-10-31
[ [ "Gies", "Holger", "", "Tubingen U." ], [ "Shaisultanov", "Rashid", "", "Tubingen U." ] ]
An expression for the axial vector current in a strong, slowly varying electromagnetic field is obtained. We apply this expression to the construction of the effective action for low-energy neutrino-photon interactions.
hep-ph/0106055
Francesco Murgia
M. Anselmino (1), M. Boglione (2), U. D'Alesio (3), F. Murgia (3) ((1) University and INFN, Torino, Italy, (2) Durham University, UK, (3) University and INFN, Cagliari, Italy)
Weak interactions in polarized semi-inclusive DIS
LaTeX, 33+1 pages, 12 ps figures, uses epsfig.sty
Eur.Phys.J.C21:501-512,2001
10.1007/s100520100741
DFTT 16/2001, INFNCA-TH0105, IPPP/01/25, DCPT/01/50
hep-ph
null
We calculate, within pQCD parton model at leading orders, the expression of the polarization P of spin 1/2 hadrons (typically Lambda baryons), produced in polarized semi-inclusive DIS in all possible cases in which weak interactions are involved. We discuss how to gather new information on fragmentation and distribution functions and give numerical estimates in the cases for which data are or will soon be available.
[ { "created": "Tue, 5 Jun 2001 17:08:20 GMT", "version": "v1" } ]
2009-01-07
[ [ "Anselmino", "M.", "" ], [ "Boglione", "M.", "" ], [ "D'Alesio", "U.", "" ], [ "Murgia", "F.", "" ] ]
We calculate, within pQCD parton model at leading orders, the expression of the polarization P of spin 1/2 hadrons (typically Lambda baryons), produced in polarized semi-inclusive DIS in all possible cases in which weak interactions are involved. We discuss how to gather new information on fragmentation and distribution functions and give numerical estimates in the cases for which data are or will soon be available.
2305.08095
Yuxuan He
Yuxuan He, Jia Liu, Xiaolin Ma, Xiao-Ping Wang
Exploring Ultralight Scalar Assistance in Sterile Neutrino Dark Matter: Cold Spectrum and Unusual X/Gamma-ray Signatures
20 pages, 5 figures, 1 table; v2: matched to journal version
JCAP 09 (2023) 047
10.1088/1475-7516/2023/09/047
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present a scalar-driven sterile neutrino production model where the interaction with the ultralight scalar field modifies the oscillation production of sterile neutrinos in the early universe. The model effectively suppresses the production of sterile neutrinos at low temperatures due to the heavy scalar mass, resulting in a colder matter power spectrum that avoids constraints from small-scale structure observations. In this model, the dominant dark matter relic is from sterile neutrinos, with only a small fraction originating from the ultralight scalar. Furthermore, the model predicts a detectable X/gamma-ray flux proportional to the cubic density of local sterile neutrinos for a light scalar mass due to the light scalar coupling to sterile neutrinos. This distinguishes our model from normal decaying dark matter, which has a linear dependence on the density. In addition, the model predicts a potential low-energy monochromatic neutrino signal that can be detectable by future neutrino telescopes.
[ { "created": "Sun, 14 May 2023 08:20:14 GMT", "version": "v1" }, { "created": "Tue, 12 Sep 2023 02:06:20 GMT", "version": "v2" } ]
2023-09-28
[ [ "He", "Yuxuan", "" ], [ "Liu", "Jia", "" ], [ "Ma", "Xiaolin", "" ], [ "Wang", "Xiao-Ping", "" ] ]
We present a scalar-driven sterile neutrino production model where the interaction with the ultralight scalar field modifies the oscillation production of sterile neutrinos in the early universe. The model effectively suppresses the production of sterile neutrinos at low temperatures due to the heavy scalar mass, resulting in a colder matter power spectrum that avoids constraints from small-scale structure observations. In this model, the dominant dark matter relic is from sterile neutrinos, with only a small fraction originating from the ultralight scalar. Furthermore, the model predicts a detectable X/gamma-ray flux proportional to the cubic density of local sterile neutrinos for a light scalar mass due to the light scalar coupling to sterile neutrinos. This distinguishes our model from normal decaying dark matter, which has a linear dependence on the density. In addition, the model predicts a potential low-energy monochromatic neutrino signal that can be detectable by future neutrino telescopes.
1309.4219
S Dev Sharma
S. Dev, Radha Raman Gautam, Lal Singh
Charged Lepton Corrections to Scaling Neutrino Mixing
12 pages, 2 figures
Phys.Rev.D89:013006,2014
10.1103/PhysRevD.89.013006
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Assuming Majorana nature of neutrinos, a general expression for the charged lepton corrections to scaling neutrino mixing has been obtained in the context of three flavor neutrino oscillations. Non-zero value of the reactor mixing angle is nicely accommodated. It is noted that scaling in the effective neutrino mass matrix is equivalent to the presence of two vanishing minors corresponding to first row elements of the effective neutrino mass matrix. A value of reactor mixing angle which is fairly close to the currently measured best fit is predicted for charged lepton corrections of the order of the Cabbibo angle. We, also, present symmetry realization of such texture structures in the framework of type-I seesaw mechanism with non-diagonal charged lepton mass matrix using discrete Abelian flavor symmetry.
[ { "created": "Tue, 17 Sep 2013 08:11:40 GMT", "version": "v1" }, { "created": "Mon, 20 Jan 2014 09:46:41 GMT", "version": "v2" } ]
2014-01-21
[ [ "Dev", "S.", "" ], [ "Gautam", "Radha Raman", "" ], [ "Singh", "Lal", "" ] ]
Assuming Majorana nature of neutrinos, a general expression for the charged lepton corrections to scaling neutrino mixing has been obtained in the context of three flavor neutrino oscillations. Non-zero value of the reactor mixing angle is nicely accommodated. It is noted that scaling in the effective neutrino mass matrix is equivalent to the presence of two vanishing minors corresponding to first row elements of the effective neutrino mass matrix. A value of reactor mixing angle which is fairly close to the currently measured best fit is predicted for charged lepton corrections of the order of the Cabbibo angle. We, also, present symmetry realization of such texture structures in the framework of type-I seesaw mechanism with non-diagonal charged lepton mass matrix using discrete Abelian flavor symmetry.
1204.1547
Ichiro Oda
Ichiro Oda
Velocity of Light in Dark Matter with Charge
10 pages
null
10.1142/S0217732312501167
DPUR/TH/30
hep-ph gr-qc hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose an interesting mechanism to reconcile the recent experiments of the Michelson-Morley type and slowdown of the velocity of light in dark matter with a fractional electric charge when the index of refraction of dark matter depends on the frequency of a photon. After deriving the formula for the velocity of light in a medium with the index of refraction $n(\omega)$ in a relativistic regime, it is shown that the local anisotropy of the light speed is proportional to the second order in $n(\omega) - 1$. This result implies that the experiments of the Michelson-Morley type do not give rise to a stringent constraint on the slowdown of the velocity of light in dark matter with electric charge.
[ { "created": "Fri, 6 Apr 2012 19:56:20 GMT", "version": "v1" } ]
2015-06-04
[ [ "Oda", "Ichiro", "" ] ]
We propose an interesting mechanism to reconcile the recent experiments of the Michelson-Morley type and slowdown of the velocity of light in dark matter with a fractional electric charge when the index of refraction of dark matter depends on the frequency of a photon. After deriving the formula for the velocity of light in a medium with the index of refraction $n(\omega)$ in a relativistic regime, it is shown that the local anisotropy of the light speed is proportional to the second order in $n(\omega) - 1$. This result implies that the experiments of the Michelson-Morley type do not give rise to a stringent constraint on the slowdown of the velocity of light in dark matter with electric charge.
hep-ph/0109175
Nina Shevchenko
B.N. Kalinkin and Yu.F. Gagarin
New Indications of Changing the Regime of Multiple Production at Superhigh Energies
latex, 12 pages, 2 figures
null
null
null
hep-ph
null
The effect of alignment of secondary particles (products of hadron interactions at superhigh energies $E^\mathrm{{in}}\geq5\cdot10^{6}$ GeV) as a "fan", which has been observed in cosmic rays, is analysed. It is shown that its main specific features are well described within the model that we proposed twenty years ago to explain sharp anomalies in the process of multiple production, which are observed in the same energy range. This model assumes that quarks have internal massive degrees of freedom. Some consequences of the used approach are discussed, which may be important for the multiple process in the above-mentioned region.
[ { "created": "Thu, 20 Sep 2001 02:56:53 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kalinkin", "B. N.", "" ], [ "Gagarin", "Yu. F.", "" ] ]
The effect of alignment of secondary particles (products of hadron interactions at superhigh energies $E^\mathrm{{in}}\geq5\cdot10^{6}$ GeV) as a "fan", which has been observed in cosmic rays, is analysed. It is shown that its main specific features are well described within the model that we proposed twenty years ago to explain sharp anomalies in the process of multiple production, which are observed in the same energy range. This model assumes that quarks have internal massive degrees of freedom. Some consequences of the used approach are discussed, which may be important for the multiple process in the above-mentioned region.
hep-ph/9607205
Gilberto Colangelo
Gilberto Colangelo
Comparison of Lattice and Chiral Perturbation Theory calculations of pion scattering lengths
Plain Latex, 7 pages, 2 figures
Phys.Lett. B395 (1997) 289-292
10.1016/S0370-2693(97)00057-9
BUTP--96/15
hep-ph hep-lat
null
I compare the lattice calculation of Fukugita et al. for the pion S-wave scattering lengths to the predictions of Chiral Perturbation Theory to two loop accuracy. I find good agreement, despite the use of the quenched approximation in the lattice calculation.
[ { "created": "Mon, 1 Jul 1996 15:01:13 GMT", "version": "v1" } ]
2009-10-28
[ [ "Colangelo", "Gilberto", "" ] ]
I compare the lattice calculation of Fukugita et al. for the pion S-wave scattering lengths to the predictions of Chiral Perturbation Theory to two loop accuracy. I find good agreement, despite the use of the quenched approximation in the lattice calculation.
2405.08110
Ryan Plestid
Ryan Plestid
The effective field theory of extended Wilson lines
null
null
null
CALT-TH-019
hep-ph hep-th nucl-th
http://creativecommons.org/licenses/by/4.0/
We construct the effective theory of electrically charged, spatially extended, infinitely heavy objects at leading power. The theory may be viewed as a generalization of NRQED for particles with a finite charge distribution where the charge radius and higher moments of the charge distribution are counted as $O(1)$ rather than $O(1/M)$. We show this is equivalent to a Wilson line traced by the worldline of an extended charge distribution. Our canonical use case is atomic nuclei with large charge $Z\gg 1$. The theory allows for the insertion of external operators and is sufficiently general to allow a treatment of both electromagnetic and weak mediated lepton-nucleus scattering including charged-current processes. This provides a first step towards the factorization of Coulomb regions, including structure dependence arising from a finite charge distribution, for scattering with nuclei.
[ { "created": "Mon, 13 May 2024 18:45:17 GMT", "version": "v1" } ]
2024-05-15
[ [ "Plestid", "Ryan", "" ] ]
We construct the effective theory of electrically charged, spatially extended, infinitely heavy objects at leading power. The theory may be viewed as a generalization of NRQED for particles with a finite charge distribution where the charge radius and higher moments of the charge distribution are counted as $O(1)$ rather than $O(1/M)$. We show this is equivalent to a Wilson line traced by the worldline of an extended charge distribution. Our canonical use case is atomic nuclei with large charge $Z\gg 1$. The theory allows for the insertion of external operators and is sufficiently general to allow a treatment of both electromagnetic and weak mediated lepton-nucleus scattering including charged-current processes. This provides a first step towards the factorization of Coulomb regions, including structure dependence arising from a finite charge distribution, for scattering with nuclei.
hep-ph/9803341
Krishna Rajagopal
Krishna Rajagopal (MIT)
QCD at Finite Baryon Density: Chiral Symmetry Restoration and Color Superconductivity
12 pages; latex with ptptex; Contribution to appear in the proceedings of the YKIS 97 Worshop, Kyoto
Prog.Theor.Phys.Suppl.131:619-631,1998
10.1143/PTPS.131.619
MIT-CTP-2718
hep-ph
null
We use a variational procedure to study finite density QCD in an approximation in which the interaction between quarks is modelled by that induced by instantons. We find that uniform states with conventional chiral symmetry breaking have negative pressure with respect to empty space at all but the lowest densities, and are therefore unstable. This is a precisely defined phenomenon which motivates the basic picture of hadrons assumed in the MIT bag model, with nucleons as droplets of chiral symmetry restored phase. This suggests that the phase transition to a chirally symmetric phase occurs by percolation of preexisting droplets of the symmetric phase, and in these proceedings we expand upon our previous presentation of this observation. At all densities high enough that the chirally symmetric phase fills space, color symmetry is broken by the formation of a <qq> condensate of quark Cooper pairs. A plausible ordering scheme leads to a substantial gap in a Lorentz scalar channel involving quarks of two colors.
[ { "created": "Fri, 13 Mar 1998 14:08:03 GMT", "version": "v1" } ]
2008-11-26
[ [ "Rajagopal", "Krishna", "", "MIT" ] ]
We use a variational procedure to study finite density QCD in an approximation in which the interaction between quarks is modelled by that induced by instantons. We find that uniform states with conventional chiral symmetry breaking have negative pressure with respect to empty space at all but the lowest densities, and are therefore unstable. This is a precisely defined phenomenon which motivates the basic picture of hadrons assumed in the MIT bag model, with nucleons as droplets of chiral symmetry restored phase. This suggests that the phase transition to a chirally symmetric phase occurs by percolation of preexisting droplets of the symmetric phase, and in these proceedings we expand upon our previous presentation of this observation. At all densities high enough that the chirally symmetric phase fills space, color symmetry is broken by the formation of a <qq> condensate of quark Cooper pairs. A plausible ordering scheme leads to a substantial gap in a Lorentz scalar channel involving quarks of two colors.
1511.03969
Fa Peng Huang
Fa Peng Huang, Pei-Hong Gu, Peng-Fei Yin, Zhao-Huan Yu and Xinmin Zhang
Testing the electroweak phase transition and electroweak baryogenesis at the LHC and a circular electron-positron collider
18 pages, 14 figures;version published in Phys.Rev.D
Phys. Rev. D 93, 103515 (2016)
10.1103/PhysRevD.93.103515
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the collider phenomenology of the electroweak phase transition and electroweak baryogenesis in the framework of the effective field theory. Our study shows that the effective theory using the dimension-6 operators can enforce strong first order phase transition and provide sizable CP violation to realize a successful electroweak baryogenesis. Such dimension-6 operators can induce interesting Higgs phenomenology that can be verified at colliders such as the LHC and the planning CEPC. We then demonstrate that this effective theory can originate from vector-like quarks and the triplet Higgs.
[ { "created": "Thu, 12 Nov 2015 17:02:04 GMT", "version": "v1" }, { "created": "Sun, 6 Dec 2015 07:07:20 GMT", "version": "v2" }, { "created": "Tue, 17 May 2016 14:47:27 GMT", "version": "v3" } ]
2016-05-25
[ [ "Huang", "Fa Peng", "" ], [ "Gu", "Pei-Hong", "" ], [ "Yin", "Peng-Fei", "" ], [ "Yu", "Zhao-Huan", "" ], [ "Zhang", "Xinmin", "" ] ]
We study the collider phenomenology of the electroweak phase transition and electroweak baryogenesis in the framework of the effective field theory. Our study shows that the effective theory using the dimension-6 operators can enforce strong first order phase transition and provide sizable CP violation to realize a successful electroweak baryogenesis. Such dimension-6 operators can induce interesting Higgs phenomenology that can be verified at colliders such as the LHC and the planning CEPC. We then demonstrate that this effective theory can originate from vector-like quarks and the triplet Higgs.
hep-ph/9401260
null
Enrico Nardi and Thomas G. Rizzo
Identifying Unconventional E$_{\bf 6}$ Models at $e^+ e^-$ Colliders
Plain Tex, 15 pages, + 9 figure available upon request (nardi@umiphys.bitnet or rizzo@scs.slac.stanford.edu), UM-TH 93--14
Phys.Rev. D50 (1994) 203-209
10.1103/PhysRevD.50.203
null
hep-ph
null
Recently it was shown that, in the framework of superstring inspired $\E$ models, the presence of generation dependent discrete symmetries allows us to construct a phenomenologically viable class of models in which the three generations of fermions do not have the same embedding within the fundamental {\bf 27} dimensional representation of E$_6$. In this scenario, these different embeddings of the conventional fermions imply that the left-handed charged leptons and the right-handed $d$-type quarks are coupled in a non--universal way to the new neutral gauge bosons $(Z_\theta)$ present in these models. It was also shown that a unique signature for this scenario, would be a deviation from unity for the ratio of cross sections for the production of two different lepton species in $e^+e^-$ annihilation. However, several different scenarios are possible, depending on the particular assignment chosen for $e_L$, $\mu_L$ and $\tau_L$ and for the right-handed $d$-type quarks, as well as on the type of $Z_\theta$ boson. Such scenarios can not be disentangled from one another by means of cross section measurements alone. In this paper we examine the possibility of identifying the pattern of embeddings through measurements of polarized and unpolarized asymmetries for fermion pair-production at the 500 GeV $e^+e^-$ Next Linear Collider (NLC). We show that it will be possible to identify the different patterns of unconventional assignments for the left-handed leptons and for the $b_R$ quark, for $Z_\theta$ masses as large as $\sim 1.5$ TeV.
[ { "created": "Sat, 15 Jan 1994 02:21:48 GMT", "version": "v1" } ]
2009-10-28
[ [ "Nardi", "Enrico", "" ], [ "Rizzo", "Thomas G.", "" ] ]
Recently it was shown that, in the framework of superstring inspired $\E$ models, the presence of generation dependent discrete symmetries allows us to construct a phenomenologically viable class of models in which the three generations of fermions do not have the same embedding within the fundamental {\bf 27} dimensional representation of E$_6$. In this scenario, these different embeddings of the conventional fermions imply that the left-handed charged leptons and the right-handed $d$-type quarks are coupled in a non--universal way to the new neutral gauge bosons $(Z_\theta)$ present in these models. It was also shown that a unique signature for this scenario, would be a deviation from unity for the ratio of cross sections for the production of two different lepton species in $e^+e^-$ annihilation. However, several different scenarios are possible, depending on the particular assignment chosen for $e_L$, $\mu_L$ and $\tau_L$ and for the right-handed $d$-type quarks, as well as on the type of $Z_\theta$ boson. Such scenarios can not be disentangled from one another by means of cross section measurements alone. In this paper we examine the possibility of identifying the pattern of embeddings through measurements of polarized and unpolarized asymmetries for fermion pair-production at the 500 GeV $e^+e^-$ Next Linear Collider (NLC). We show that it will be possible to identify the different patterns of unconventional assignments for the left-handed leptons and for the $b_R$ quark, for $Z_\theta$ masses as large as $\sim 1.5$ TeV.
hep-ph/0102130
Jungil Lee
Eric Braaten (OSU), Jungil Lee (DESY)
Fragmentation Functions for Lepton Pairs
13 pages, 4 figures, normalization corrected, text abbreviated
Phys.Rev. D65 (2002) 034005
10.1103/PhysRevD.65.034005
IPPP/01/04,DCPT/01/08
hep-ph
null
We calculate the fragmentation function for a light quark to decay into a lepton pair to leading order in the QCD coupling constant. In the formal definition of the fragmentation function, a QED phase must be included in the eikonal factor to guarantee QED gauge invariance. We find that the longitudinal polarization fraction is a decreasing function of the factorization scale, in accord with the intuitive expectation that the virtual photon should behave more and more like a real photon as the transverse momomentum of the fragmenting quark increases.
[ { "created": "Sun, 11 Feb 2001 01:56:18 GMT", "version": "v1" }, { "created": "Sat, 17 Feb 2001 01:17:53 GMT", "version": "v2" } ]
2009-11-07
[ [ "Braaten", "Eric", "", "OSU" ], [ "Lee", "Jungil", "", "DESY" ] ]
We calculate the fragmentation function for a light quark to decay into a lepton pair to leading order in the QCD coupling constant. In the formal definition of the fragmentation function, a QED phase must be included in the eikonal factor to guarantee QED gauge invariance. We find that the longitudinal polarization fraction is a decreasing function of the factorization scale, in accord with the intuitive expectation that the virtual photon should behave more and more like a real photon as the transverse momomentum of the fragmenting quark increases.
hep-ph/9411308
Hnli
Hsiang-nan Li and Hoi-Lai Yu
Perturbative QCD Analysis of $B$ Meson Decays
26 pages in latex, figures are available for request
Phys.Rev.D53:2480-2490,1996
10.1103/PhysRevD.53.2480
CCUTH-94-04, IP-ASTP-12-94
hep-ph
null
Resummation of large QCD radiative corrections, including leading and next-to-leading logarithms, in pion electromagnetic form factor is reviewed. Similar formalism is applied to exclusive processes involving heavy mesons, and leads to Sudakov suppression for the semi-leptonic decay $B\to\pi l\nu$. It is found that, with the inclusion of Sudakov effects, perturbative QCD analysis of this decay is possible for the energy fraction of the pion above 0.3. By combining predictions from the soft pion theorems, we estimate that the upper limit of the KM matrix element $|V_{ub}|$ is roughly 0.003.
[ { "created": "Wed, 16 Nov 1994 21:17:06 GMT", "version": "v1" } ]
2009-09-25
[ [ "Li", "Hsiang-nan", "" ], [ "Yu", "Hoi-Lai", "" ] ]
Resummation of large QCD radiative corrections, including leading and next-to-leading logarithms, in pion electromagnetic form factor is reviewed. Similar formalism is applied to exclusive processes involving heavy mesons, and leads to Sudakov suppression for the semi-leptonic decay $B\to\pi l\nu$. It is found that, with the inclusion of Sudakov effects, perturbative QCD analysis of this decay is possible for the energy fraction of the pion above 0.3. By combining predictions from the soft pion theorems, we estimate that the upper limit of the KM matrix element $|V_{ub}|$ is roughly 0.003.
hep-ph/9906336
Jan Kalinowski
Jan Kalinowski
Finding CP-violating Higgses
1+4 pages, 1 figure, uses moriond.sty (included), talk given at 34th Rencontres de Moriond: Electroweak Interactions and Unified Theories, Les Arcs, France, 13-20 March 1999
null
null
IFT/99-11
hep-ph
null
In a general two-Higgs-doublet model with CP violation in the Higgs sector, the three neutral physical Higgs bosons have no definite CP properties. A new sum rule relating Yukawa and Higgs-Z couplings implies that a neutral Higgs boson cannot escape detection at an e^+e^- collider if it is kinematically accessible in Z+Higgs, $b\bar b+$Higgs and $t\bar t+$Higgs production, irrespective of the mixing angles and the masses of the other neutral Higgs bosons. The implications of the sum rules for Higgs discovery at the Tevatron and LHC are briefly mentioned.
[ { "created": "Fri, 11 Jun 1999 13:53:03 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kalinowski", "Jan", "" ] ]
In a general two-Higgs-doublet model with CP violation in the Higgs sector, the three neutral physical Higgs bosons have no definite CP properties. A new sum rule relating Yukawa and Higgs-Z couplings implies that a neutral Higgs boson cannot escape detection at an e^+e^- collider if it is kinematically accessible in Z+Higgs, $b\bar b+$Higgs and $t\bar t+$Higgs production, irrespective of the mixing angles and the masses of the other neutral Higgs bosons. The implications of the sum rules for Higgs discovery at the Tevatron and LHC are briefly mentioned.
2012.06582
Yue-Shi Lai
Yue Shi Lai, Duff Neill, Mateusz P{\l}osko\'n, Felix Ringer
Explainable machine learning of the underlying physics of high-energy particle collisions
11 pages, 4 figures
null
10.1016/j.physletb.2022.137055
null
hep-ph nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We present an implementation of an explainable and physics-aware machine learning model capable of inferring the underlying physics of high-energy particle collisions using the information encoded in the energy-momentum four-vectors of the final state particles. We demonstrate the proof-of-concept of our White Box AI approach using a Generative Adversarial Network (GAN) which learns from a DGLAP-based parton shower Monte Carlo event generator. We show, for the first time, that our approach leads to a network that is able to learn not only the final distribution of particles, but also the underlying parton branching mechanism, i.e. the Altarelli-Parisi splitting function, the ordering variable of the shower, and the scaling behavior. While the current work is focused on perturbative physics of the parton shower, we foresee a broad range of applications of our framework to areas that are currently difficult to address from first principles in QCD. Examples include nonperturbative and collective effects, factorization breaking and the modification of the parton shower in heavy-ion, and electron-nucleus collisions.
[ { "created": "Fri, 11 Dec 2020 19:00:01 GMT", "version": "v1" } ]
2022-04-20
[ [ "Lai", "Yue Shi", "" ], [ "Neill", "Duff", "" ], [ "Płoskoń", "Mateusz", "" ], [ "Ringer", "Felix", "" ] ]
We present an implementation of an explainable and physics-aware machine learning model capable of inferring the underlying physics of high-energy particle collisions using the information encoded in the energy-momentum four-vectors of the final state particles. We demonstrate the proof-of-concept of our White Box AI approach using a Generative Adversarial Network (GAN) which learns from a DGLAP-based parton shower Monte Carlo event generator. We show, for the first time, that our approach leads to a network that is able to learn not only the final distribution of particles, but also the underlying parton branching mechanism, i.e. the Altarelli-Parisi splitting function, the ordering variable of the shower, and the scaling behavior. While the current work is focused on perturbative physics of the parton shower, we foresee a broad range of applications of our framework to areas that are currently difficult to address from first principles in QCD. Examples include nonperturbative and collective effects, factorization breaking and the modification of the parton shower in heavy-ion, and electron-nucleus collisions.
2202.01443
Shivam Gola
Arindam Das, Shivam Gola, Sanjoy Mandal and Nita Sinha
Two-component scalar and fermionic dark matter candidates in a generic U$(1)_X$ model
One Table changed
null
10.1016/j.physletb.2022.137117
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
We consider a $U(1)_X\otimes \mathbb{Z}_2\otimes \mathbb{Z}'_2$ extension of the Standard Model (SM), where the $U(1)_X$ charge of an SM field is given by a linear combination of its hypercharge and B$-$L number. Apart from the SM particle content, the model contains three right-handed neutrinos (RHNs) $N_R^i$ and two scalars $\Phi$, $\chi$, all singlets under the SM gauge group but charged under $U(1)_X$ gauge group. Two of these additional fields, fermion $N_R^3$ is odd under $\mathbb{Z}_2$ and scalar $\chi$ is odd under $\mathbb{Z}'_2$ symmetry. Thus both $\chi$ and $N_R^3$ contribute to the observed dark matter relic density, leading to two-component dark matter candidates. We study in detail its dark matter properties such as relic density and direct detection taking into account the constraints coming from collider studies. We find that in our model, there can be possible annihilation of one Dark Matter (DM) into the other, which may potentially alter the relic density in a significant way.
[ { "created": "Thu, 3 Feb 2022 07:23:56 GMT", "version": "v1" }, { "created": "Tue, 15 Feb 2022 14:04:47 GMT", "version": "v2" }, { "created": "Wed, 27 Apr 2022 09:03:13 GMT", "version": "v3" } ]
2022-05-04
[ [ "Das", "Arindam", "" ], [ "Gola", "Shivam", "" ], [ "Mandal", "Sanjoy", "" ], [ "Sinha", "Nita", "" ] ]
We consider a $U(1)_X\otimes \mathbb{Z}_2\otimes \mathbb{Z}'_2$ extension of the Standard Model (SM), where the $U(1)_X$ charge of an SM field is given by a linear combination of its hypercharge and B$-$L number. Apart from the SM particle content, the model contains three right-handed neutrinos (RHNs) $N_R^i$ and two scalars $\Phi$, $\chi$, all singlets under the SM gauge group but charged under $U(1)_X$ gauge group. Two of these additional fields, fermion $N_R^3$ is odd under $\mathbb{Z}_2$ and scalar $\chi$ is odd under $\mathbb{Z}'_2$ symmetry. Thus both $\chi$ and $N_R^3$ contribute to the observed dark matter relic density, leading to two-component dark matter candidates. We study in detail its dark matter properties such as relic density and direct detection taking into account the constraints coming from collider studies. We find that in our model, there can be possible annihilation of one Dark Matter (DM) into the other, which may potentially alter the relic density in a significant way.
1805.11172
Rohoollah Mohammadi
S. Mahmoudi, M. Haghighat, S. Modares Vamegh and R. Mohammadi
Dipolar dark matter and CMB B-mode polarization
null
null
null
null
hep-ph astro-ph.CO astro-ph.HE
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider dark matter as singlet fermionic particles which carrying magnetic dipole moment to explore its contribution on the polarization of cosmic microwave background (CMB) photons. We show that Dirac fermionic dark matter has no contribution on the CMB polarization. However, in the case of Majorana dark matter this type of interaction leads to the B-mode polarization in presence of primordial scalar perturbations which is in contrast with standard scenario for the CMB polarization. We numerically calculate the B-mode power spectra and plot $C_l^{BB}$ for different dark matter masses and the $r$-parameter. We show that the dark matter with masses less than 100MeV have valuable contribution on $C_l^{BB}$. Meanwhile, the dark matters with mass $m_d\leq50MeV$ for $r=0.07$ ( $m_d\leq80MeV$ for $r=0.09$) can be excluded experimentally. Furthermore, our results put a bound on the magnetic dipole moment about $M\leq 10^{-16} e\,\,cm$ in agreement with the other reported constraints.
[ { "created": "Mon, 28 May 2018 20:56:42 GMT", "version": "v1" }, { "created": "Mon, 29 Oct 2018 19:18:02 GMT", "version": "v2" } ]
2018-10-31
[ [ "Mahmoudi", "S.", "" ], [ "Haghighat", "M.", "" ], [ "Vamegh", "S. Modares", "" ], [ "Mohammadi", "R.", "" ] ]
We consider dark matter as singlet fermionic particles which carrying magnetic dipole moment to explore its contribution on the polarization of cosmic microwave background (CMB) photons. We show that Dirac fermionic dark matter has no contribution on the CMB polarization. However, in the case of Majorana dark matter this type of interaction leads to the B-mode polarization in presence of primordial scalar perturbations which is in contrast with standard scenario for the CMB polarization. We numerically calculate the B-mode power spectra and plot $C_l^{BB}$ for different dark matter masses and the $r$-parameter. We show that the dark matter with masses less than 100MeV have valuable contribution on $C_l^{BB}$. Meanwhile, the dark matters with mass $m_d\leq50MeV$ for $r=0.07$ ( $m_d\leq80MeV$ for $r=0.09$) can be excluded experimentally. Furthermore, our results put a bound on the magnetic dipole moment about $M\leq 10^{-16} e\,\,cm$ in agreement with the other reported constraints.
1302.5667
Hiroaki Kohyama
T. Inagaki, D. Kimura, H. Kohyama, A. Kvinikhidze
Regularization parameter independent analysis in Nambu-Jona-Lasinio model
9 pages, 6 figures
null
10.1142/S0217751X13501649
HUPD-1212
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Nambu-Jona-Lasinio model used to investigate low energy phenomena is nonrenormalizable, therefore the results depend on the regularization parameter in general. A possibility of the finite in four-dimensional limit and even the regularization parameter (this is dimension in the dimensional regularization scheme) independent analysis is shown in the leading order of the 1/Nc expansion.
[ { "created": "Fri, 22 Feb 2013 18:09:40 GMT", "version": "v1" } ]
2015-06-15
[ [ "Inagaki", "T.", "" ], [ "Kimura", "D.", "" ], [ "Kohyama", "H.", "" ], [ "Kvinikhidze", "A.", "" ] ]
Nambu-Jona-Lasinio model used to investigate low energy phenomena is nonrenormalizable, therefore the results depend on the regularization parameter in general. A possibility of the finite in four-dimensional limit and even the regularization parameter (this is dimension in the dimensional regularization scheme) independent analysis is shown in the leading order of the 1/Nc expansion.
1005.1607
Sergey Kovalenko
Juan Carlos Helo, Sergey Kovalenko, Ivan Schmidt
Sterile neutrinos in lepton number and lepton flavor violating decays
13 pages, 4 figures. Published version
Nucl.Phys.B853:80-104,2011
10.1016/j.nuclphysb.2011.07.020
null
hep-ph astro-ph.HE hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study the contribution of massive dominantly sterile neutrinos, $N$, to the Lepton Number and Lepton Flavor Violating semileptonic decays of $\tau$ and $B, D, K$-mesons. We focus on special domains of sterile neutrino masses $m_{N}$ where it is close to its mass-shell. This leads to an enormous resonant enhancement of the decay rates of these processes. This allows us to derive stringent limits on the sterile neutrino mass $m_{N}$ and its mixing $U_{\alpha N}$ with active flavors. We apply a joint analysis of the existing experimental bounds on the decay rates of the studied processes. In contrast to other approaches in the literature our limits are free from ad hoc assumptions on the relative size of the sterile neutrino mixing parameters. We analyze the impact of this sort of assumptions on the extraction of the limits on $m_{N}$ and $U_{\alpha N}$, and discuss the effect of finite detector size. Special attention was paid to the limits on meson decays with $e^{\pm}e^{\pm}$ in final state, derived from non-observation of $0\nu\beta\beta$-decay. We point out that observation of these decays may, in particular, shed light on the Majorana phases of the neutrino mixing matrix.
[ { "created": "Mon, 10 May 2010 16:42:25 GMT", "version": "v1" }, { "created": "Mon, 26 Aug 2013 03:29:44 GMT", "version": "v2" } ]
2013-08-27
[ [ "Helo", "Juan Carlos", "" ], [ "Kovalenko", "Sergey", "" ], [ "Schmidt", "Ivan", "" ] ]
We study the contribution of massive dominantly sterile neutrinos, $N$, to the Lepton Number and Lepton Flavor Violating semileptonic decays of $\tau$ and $B, D, K$-mesons. We focus on special domains of sterile neutrino masses $m_{N}$ where it is close to its mass-shell. This leads to an enormous resonant enhancement of the decay rates of these processes. This allows us to derive stringent limits on the sterile neutrino mass $m_{N}$ and its mixing $U_{\alpha N}$ with active flavors. We apply a joint analysis of the existing experimental bounds on the decay rates of the studied processes. In contrast to other approaches in the literature our limits are free from ad hoc assumptions on the relative size of the sterile neutrino mixing parameters. We analyze the impact of this sort of assumptions on the extraction of the limits on $m_{N}$ and $U_{\alpha N}$, and discuss the effect of finite detector size. Special attention was paid to the limits on meson decays with $e^{\pm}e^{\pm}$ in final state, derived from non-observation of $0\nu\beta\beta$-decay. We point out that observation of these decays may, in particular, shed light on the Majorana phases of the neutrino mixing matrix.
hep-ph/0606261
Alexander V. Kuznetsov
A.V. Kuznetsov and N.V. Mikheev (Yaroslavl State (P.G. Demidov) University, Russia)
Neutrino chirality flip in a supernova and the bound on the neutrino magnetic moment
7 pages, LaTeX, 5 EPS figures, based on the talk presented by N.V. Mikheev at the XIV International Seminar Quarks'2006, St.-Petersburg, Repino, Russia, May 19-25, 2006, to appear in the Proceedings
null
null
YARU-HE-06/04
hep-ph astro-ph
null
The neutrino chirality-flip process under the conditions of the supernova core is investigated in detail with the plasma polarization effects in the photon propagator taken into account. It is shown that the contribution of the proton fraction of plasma is essential. New upper bounds on the neutrino magnetic moment are obtained: mu_nu < (0.5 - 1.1) 10^{-12} mu_B from the limit on the supernova core luminosity for nu_R emission, and mu_nu < (0.4 - 0.6) 10^{-12} mu_B from the limit on the averaged time of the neutrino spin-flip. The best astrophysical upper bound on the neutrino magnetic moment is improved by the factor of 3 to 7.
[ { "created": "Sun, 25 Jun 2006 06:37:27 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kuznetsov", "A. V.", "", "Yaroslavl State" ], [ "Mikheev", "N. V.", "", "Yaroslavl State" ] ]
The neutrino chirality-flip process under the conditions of the supernova core is investigated in detail with the plasma polarization effects in the photon propagator taken into account. It is shown that the contribution of the proton fraction of plasma is essential. New upper bounds on the neutrino magnetic moment are obtained: mu_nu < (0.5 - 1.1) 10^{-12} mu_B from the limit on the supernova core luminosity for nu_R emission, and mu_nu < (0.4 - 0.6) 10^{-12} mu_B from the limit on the averaged time of the neutrino spin-flip. The best astrophysical upper bound on the neutrino magnetic moment is improved by the factor of 3 to 7.
1311.0848
Thomas A. Ryttov
Thomas A. Ryttov
Infrared Fixed Points in the minimal MOM Scheme
Published version. Several changes to text. arXiv admin note: text overlap with arXiv:1309.3867
Phys.Rev. D89 (2014) 056001
10.1103/PhysRevD.89.056001
CP3-Origins-2013-043 DNRF 90, DIAS-2013-43
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We analyze the behavior of several renormalization group functions at infrared fixed points for $SU(N)$ gauge theories with fermions in the fundamental and two-indexed representations. This includes the beta function of the gauge coupling, the anomalous dimension of the gauge parameter and the anomalous dimension of the mass. The scheme in which the analysis is performed is the minimal momentum subtraction scheme through third loop order. Due to the fact that scheme dependence is inevitable once the perturbation theory is truncated we compare to previous identical studies done in the minimal subtraction scheme and the modified regularization invariant scheme. We find only mild to moderate scheme dependence.
[ { "created": "Mon, 4 Nov 2013 20:51:24 GMT", "version": "v1" }, { "created": "Mon, 17 Mar 2014 13:14:22 GMT", "version": "v2" } ]
2014-03-18
[ [ "Ryttov", "Thomas A.", "" ] ]
We analyze the behavior of several renormalization group functions at infrared fixed points for $SU(N)$ gauge theories with fermions in the fundamental and two-indexed representations. This includes the beta function of the gauge coupling, the anomalous dimension of the gauge parameter and the anomalous dimension of the mass. The scheme in which the analysis is performed is the minimal momentum subtraction scheme through third loop order. Due to the fact that scheme dependence is inevitable once the perturbation theory is truncated we compare to previous identical studies done in the minimal subtraction scheme and the modified regularization invariant scheme. We find only mild to moderate scheme dependence.
1909.13818
Tianbo Liu
Tianbo Liu, Raza Sabbir Sufian, Guy F. de T\'eramond, Hans G\"unter Dosch, Stanley J. Brodsky, Alexandre Deur
Unified Description of Polarized and Unpolarized Quark Distributions in the Proton
7 pages, 3 figures, version to appear in Physical Review Letters
Phys. Rev. Lett. 124, 082003 (2020)
10.1103/PhysRevLett.124.082003
JLAB-THY-19-3057, SLAC-PUB-17477
hep-ph hep-ex nucl-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose a unified new approach to describe polarized and unpolarized quark distributions in the proton based on the gauge-gravity correspondence, light-front holography, and the generalized Veneziano model. We find that the spin-dependent quark distributions are uniquely determined in terms of the unpolarized distributions by chirality separation without the introduction of additional free parameters. The predictions are consistent with existing experimental data and agree with perturbative QCD constraints at large longitudinal momentum $x$. In particular, we predict the sign reversal of the polarized down-quark distribution in the proton at $x=0.8\pm0.03$, a key property of nucleon substructure which will be tested very soon in upcoming experiments.
[ { "created": "Mon, 30 Sep 2019 16:11:19 GMT", "version": "v1" }, { "created": "Fri, 21 Feb 2020 01:19:52 GMT", "version": "v2" } ]
2020-03-02
[ [ "Liu", "Tianbo", "" ], [ "Sufian", "Raza Sabbir", "" ], [ "de Téramond", "Guy F.", "" ], [ "Dosch", "Hans Günter", "" ], [ "Brodsky", "Stanley J.", "" ], [ "Deur", "Alexandre", "" ] ]
We propose a unified new approach to describe polarized and unpolarized quark distributions in the proton based on the gauge-gravity correspondence, light-front holography, and the generalized Veneziano model. We find that the spin-dependent quark distributions are uniquely determined in terms of the unpolarized distributions by chirality separation without the introduction of additional free parameters. The predictions are consistent with existing experimental data and agree with perturbative QCD constraints at large longitudinal momentum $x$. In particular, we predict the sign reversal of the polarized down-quark distribution in the proton at $x=0.8\pm0.03$, a key property of nucleon substructure which will be tested very soon in upcoming experiments.
hep-ph/0110030
V. I. Kopeikin
V. I. Kopeikin
On Search for New Physics in Nonequilibrium Reactor Antineutrino Energy Spectrum
4 pages in pdf file with figures. Talk presented at International Conference NANP-2001, Dubna, Russia, Jun-2001
Phys.Atom.Nucl. 66 (2003) 472-475; Yad.Fiz. 66 (2003) 500-503
10.1134/1.1563708
null
hep-ph
null
The calculations of the time-dependent reactor antineutrino energy spectrum are presented. Some problems associated with sensitive searches for neutrino magnetic moment and neutrino oscillations in reactor antineutrino flux are considered.
[ { "created": "Tue, 2 Oct 2001 07:31:04 GMT", "version": "v1" } ]
2015-06-25
[ [ "Kopeikin", "V. I.", "" ] ]
The calculations of the time-dependent reactor antineutrino energy spectrum are presented. Some problems associated with sensitive searches for neutrino magnetic moment and neutrino oscillations in reactor antineutrino flux are considered.
hep-ph/9903485
Huang Mei
Mei Huang, Pengfei Zhuang, and Weiqin Chao
$\pi - \pi$ Scattering Lengths and Chiral Condensate in NJL Model
1 RevTeX file, 9 pages with two tables
null
null
null
hep-ph nucl-th
null
Within the general framework of SU(2) Nambu-Jona-Lasinio model beyond mean-field approximation, the S-wave $\pi - \pi$ scattering lengths $a_0^0$ and $a_0^2$ are calculated. The numerical results are in agreement with that analyzed from recent experiment $\pi N \to \pi \pi N$ data by using Chew-Low-Goebel technique, and the corresponding chiral condensate $<{\bar q}q>$ is around $-(250 {\rm MeV})^3$, which is close to the ones obtained from lattice and sum rules.
[ { "created": "Thu, 25 Mar 1999 09:34:07 GMT", "version": "v1" } ]
2007-05-23
[ [ "Huang", "Mei", "" ], [ "Zhuang", "Pengfei", "" ], [ "Chao", "Weiqin", "" ] ]
Within the general framework of SU(2) Nambu-Jona-Lasinio model beyond mean-field approximation, the S-wave $\pi - \pi$ scattering lengths $a_0^0$ and $a_0^2$ are calculated. The numerical results are in agreement with that analyzed from recent experiment $\pi N \to \pi \pi N$ data by using Chew-Low-Goebel technique, and the corresponding chiral condensate $<{\bar q}q>$ is around $-(250 {\rm MeV})^3$, which is close to the ones obtained from lattice and sum rules.
2108.04478
Alexandre Kisselev
S.C. \.Inan and A.V. Kisselev
Probing anomalous $\gamma\gamma\gamma Z$ couplings through $\gamma Z$ production in $\gamma\gamma$ collisions at the CLIC
29 pages, 7 figures, 3 tables; minor corrections to the text, 4 references added
null
10.1007/JHEP10(2021)121
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We have estimated the sensitivity to the anomalous couplings of the $\gamma\gamma\gamma Z$ vertex in the $\gamma\gamma\rightarrow\gamma Z$ scattering of the Compton backscattered photons at the CLIC. Both polarized and unpolarized collisions at the $e^+e^-$ energies 1500 GeV and 3000 GeV are addressed, and anomalous contributions to helicity amplitudes are derived. The differential and total cross sections are calculated. We have obtained 95\% C.L. exclusion limits on the anomalous quartic gauge couplings (QGCs). They are compared with corresponding bounds derived for the $\gamma\gamma\gamma Z$ couplings via $\gamma Z$ production at the LHC. The constraints on the anomalous QGCs are one to two orders of magnitude more stringent that at the HL-LHC. The partial-wave unitarity constraints on the anomalous couplings are examined. It is shown that the unitarity is not violated in the region of the anomalous QGCs studied in the paper.
[ { "created": "Tue, 10 Aug 2021 06:56:18 GMT", "version": "v1" }, { "created": "Thu, 14 Oct 2021 06:49:40 GMT", "version": "v2" } ]
2021-11-03
[ [ "İnan", "S. C.", "" ], [ "Kisselev", "A. V.", "" ] ]
We have estimated the sensitivity to the anomalous couplings of the $\gamma\gamma\gamma Z$ vertex in the $\gamma\gamma\rightarrow\gamma Z$ scattering of the Compton backscattered photons at the CLIC. Both polarized and unpolarized collisions at the $e^+e^-$ energies 1500 GeV and 3000 GeV are addressed, and anomalous contributions to helicity amplitudes are derived. The differential and total cross sections are calculated. We have obtained 95\% C.L. exclusion limits on the anomalous quartic gauge couplings (QGCs). They are compared with corresponding bounds derived for the $\gamma\gamma\gamma Z$ couplings via $\gamma Z$ production at the LHC. The constraints on the anomalous QGCs are one to two orders of magnitude more stringent that at the HL-LHC. The partial-wave unitarity constraints on the anomalous couplings are examined. It is shown that the unitarity is not violated in the region of the anomalous QGCs studied in the paper.
1710.02544
Evan Johnson
Evan Johnson, Hong Zhang, Eric Braaten
Effective field theory for resonant wino dark matter
11 pages, 9 figures. Presented at the APS Division of Particles and Fields Meeting (DPF 2017), July 31-August 4, 2017, Fermilab. C170731
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Enhancements in WIMP annihilation rates have been identified with a nonperturbative "Sommerfeld enhancement" arising from the exchange of light mediators. At certain critical values of the WIMP mass, the enhancement is increased dramatically due to a zero-energy resonance at the WIMP-pair threshold. For masses near these critical values, WIMP scattering processes are accurately described by an effective field theory where WIMPs have nonperturbative zero-range contact interactions. The effective field theory is controlled by a renormalization-group fixed point at which the WIMPs are degenerate in mass and their scattering length is infinite. If the WIMPs can exchange massless mediators, the resulting long-range interaction must also be treated nonperturbatively. We develop an effective field theory for SU(2)-triplet dark matter, which have short-range weak and long-range electromagnetic interactions. We refer to these dark matter particles as winos. The long-range Coulomb interaction between charged winos is resummed to all orders. The parameters of the effective field theory can be determined by matching wino-wino scattering amplitudes calculated by solving the Schr\"odinger equation with a potential describing exchange of electroweak gauge bosons. With Coulomb resummation, the effective field theory at leading order gives a good description of the low-energy two-body observables for winos.
[ { "created": "Fri, 6 Oct 2017 18:31:20 GMT", "version": "v1" } ]
2017-10-10
[ [ "Johnson", "Evan", "" ], [ "Zhang", "Hong", "" ], [ "Braaten", "Eric", "" ] ]
Enhancements in WIMP annihilation rates have been identified with a nonperturbative "Sommerfeld enhancement" arising from the exchange of light mediators. At certain critical values of the WIMP mass, the enhancement is increased dramatically due to a zero-energy resonance at the WIMP-pair threshold. For masses near these critical values, WIMP scattering processes are accurately described by an effective field theory where WIMPs have nonperturbative zero-range contact interactions. The effective field theory is controlled by a renormalization-group fixed point at which the WIMPs are degenerate in mass and their scattering length is infinite. If the WIMPs can exchange massless mediators, the resulting long-range interaction must also be treated nonperturbatively. We develop an effective field theory for SU(2)-triplet dark matter, which have short-range weak and long-range electromagnetic interactions. We refer to these dark matter particles as winos. The long-range Coulomb interaction between charged winos is resummed to all orders. The parameters of the effective field theory can be determined by matching wino-wino scattering amplitudes calculated by solving the Schr\"odinger equation with a potential describing exchange of electroweak gauge bosons. With Coulomb resummation, the effective field theory at leading order gives a good description of the low-energy two-body observables for winos.
1405.0498
Arsham Farzinnia
Arsham Farzinnia, Jing Ren
Higgs Partner Searches and Dark Matter Phenomenology in a Classically Scale Invariant Higgs Boson Sector
Published version with a slight adjustment of the title per journal's suggestion
Phys. Rev. D 90, 015019 (2014)
10.1103/PhysRevD.90.015019
CTPU-14-03
hep-ph astro-ph.CO hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In a previous work, a classically scale invariant extension of the standard model was proposed, as a potential candidate for resolving the hierarchy problem, by minimally introducing a complex gauge singlet scalar, and generating radiative electroweak symmetry breaking by means of the Coleman- Weinberg Mechanism. Postulating the singlet sector to respect the CP-symmetry, the existence of a stable pseudoscalar dark matter candidate with a mass in the TeV range was demonstrated. More- over, the model predicted the presence of another physical CP-even Higgs boson (with suppressed tree-level couplings), in addition to the 125 GeV scalar discovered by the LHC. The viable region of the parameter space was determined by various theoretical and experimental considerations. In this work, we continue to examine the phenomenological implications of the proposed minimal sce- nario by considering the constraints from the dark matter relic density, as determined by the Planck collaboration, as well as the direct detection bounds from the LUX experiment. Furthermore, we investigate the implications of the collider Higgs searches for the additional Higgs boson. Our results are comprehensively demonstrated in unified exclusion plots, which analyze the viable region of the parameter space from all relevant angles, demonstrating the testability of the proposed scenario.
[ { "created": "Fri, 2 May 2014 20:08:56 GMT", "version": "v1" }, { "created": "Thu, 15 May 2014 19:52:29 GMT", "version": "v2" }, { "created": "Wed, 30 Jul 2014 18:16:45 GMT", "version": "v3" } ]
2014-07-31
[ [ "Farzinnia", "Arsham", "" ], [ "Ren", "Jing", "" ] ]
In a previous work, a classically scale invariant extension of the standard model was proposed, as a potential candidate for resolving the hierarchy problem, by minimally introducing a complex gauge singlet scalar, and generating radiative electroweak symmetry breaking by means of the Coleman- Weinberg Mechanism. Postulating the singlet sector to respect the CP-symmetry, the existence of a stable pseudoscalar dark matter candidate with a mass in the TeV range was demonstrated. More- over, the model predicted the presence of another physical CP-even Higgs boson (with suppressed tree-level couplings), in addition to the 125 GeV scalar discovered by the LHC. The viable region of the parameter space was determined by various theoretical and experimental considerations. In this work, we continue to examine the phenomenological implications of the proposed minimal sce- nario by considering the constraints from the dark matter relic density, as determined by the Planck collaboration, as well as the direct detection bounds from the LUX experiment. Furthermore, we investigate the implications of the collider Higgs searches for the additional Higgs boson. Our results are comprehensively demonstrated in unified exclusion plots, which analyze the viable region of the parameter space from all relevant angles, demonstrating the testability of the proposed scenario.
2102.02823
Samuel Homiller
Sally Dawson, Pier Paolo Giardino, Samuel Homiller
Uncovering the High Scale Higgs Singlet Model
24 pages, 8 figures
Phys. Rev. D 103, 075016 (2021)
10.1103/PhysRevD.103.075016
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The scalar singlet model extends the Standard Model with the addition of a new gauge singlet scalar. We re-examine the limits on the new scalar from oblique parameter fits and from a global fit to precision electroweak observables and present analytic expressions for our results. For the case when the new scalar is much heavier than the weak scale, we map the model onto the dimension-six Standard Model effective field theory (SMEFT) and review the allowed parameter space from unitarity considerations and from the requirement that the electroweak minimum be stable. A global fit to precision electroweak data, along with LHC observables, is used to constrain the parameters of the high scale singlet model and we determine the numerical effects of performing the matching at both tree level and 1-loop.
[ { "created": "Thu, 4 Feb 2021 19:00:00 GMT", "version": "v1" } ]
2021-04-28
[ [ "Dawson", "Sally", "" ], [ "Giardino", "Pier Paolo", "" ], [ "Homiller", "Samuel", "" ] ]
The scalar singlet model extends the Standard Model with the addition of a new gauge singlet scalar. We re-examine the limits on the new scalar from oblique parameter fits and from a global fit to precision electroweak observables and present analytic expressions for our results. For the case when the new scalar is much heavier than the weak scale, we map the model onto the dimension-six Standard Model effective field theory (SMEFT) and review the allowed parameter space from unitarity considerations and from the requirement that the electroweak minimum be stable. A global fit to precision electroweak data, along with LHC observables, is used to constrain the parameters of the high scale singlet model and we determine the numerical effects of performing the matching at both tree level and 1-loop.
1304.7647
Peihong Gu
Pei-Hong Gu
Parity: from strong CP problem to dark matter, neutrino masses and baryon asymmetry
6 pages
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that in an SU(3)_c\times [SU(2)_L\times U(1)_Y]\times [SU(2)'_R\times U(1)'_Y] framework, the parity symmetry motivated by solving the strong CP problem without resorting to an axion can predict a dark matter particle with a mass around 302 GeV. This dark matter candidate can be directly detected in the presence of a U(1)_Y\times U(1)'_Y kinetic mixing. Furthermore, our model can accommodate a natural way to simultaneously realize an inverse-linear seesaw for neutrino masses and a resonant leptogenesis for baryon asymmetry.
[ { "created": "Mon, 29 Apr 2013 12:47:59 GMT", "version": "v1" } ]
2013-04-30
[ [ "Gu", "Pei-Hong", "" ] ]
We show that in an SU(3)_c\times [SU(2)_L\times U(1)_Y]\times [SU(2)'_R\times U(1)'_Y] framework, the parity symmetry motivated by solving the strong CP problem without resorting to an axion can predict a dark matter particle with a mass around 302 GeV. This dark matter candidate can be directly detected in the presence of a U(1)_Y\times U(1)'_Y kinetic mixing. Furthermore, our model can accommodate a natural way to simultaneously realize an inverse-linear seesaw for neutrino masses and a resonant leptogenesis for baryon asymmetry.
hep-ph/0411098
Mihail Chizhov
M. V. Chizhov
On V_ud determination from neutron decay
8 pages, 1 figure included
null
null
CERN-PH-TH/2004-113
hep-ph hep-ex nucl-ex nucl-th
null
The recent results of the PIBETA experiment strongly suggest the presence of a non-(V-A) anomalous interaction in the radiative pion decay. The same interaction should inevitably contribute to the neutron decay and in particular it should affect the V_ud determination. This paper is dedicated to the prediction of the eventual discrepancy in V_ud extracted from the super-allowed Fermi transitions and from the polarized neutron decay.
[ { "created": "Sun, 7 Nov 2004 11:51:04 GMT", "version": "v1" } ]
2007-05-23
[ [ "Chizhov", "M. V.", "" ] ]
The recent results of the PIBETA experiment strongly suggest the presence of a non-(V-A) anomalous interaction in the radiative pion decay. The same interaction should inevitably contribute to the neutron decay and in particular it should affect the V_ud determination. This paper is dedicated to the prediction of the eventual discrepancy in V_ud extracted from the super-allowed Fermi transitions and from the polarized neutron decay.
hep-ph/0007095
Hubert Spiesberger
P.Post and K.Schilcher
K0 form factor at order p^6 of chiral perturbation theory
22 pages Latex with 8 figures, Typos corrected, one reference added
Nucl.Phys. B599 (2001) 30-54
10.1016/S0550-3213(00)00769-0
Mainz MZ-TH/00-31
hep-ph
null
This paper describes the calculation of the electromagnetic form factor of the K0 meson at order p^6 of chiral perturbation theory which is the next-to-leading order correction to the well-known p^4 result achieved by Gasser and Leutwyler. On the one hand, at order p^6 the chiral expansion contains 1- and 2-loop diagrams which are discussed in detail. Especially, a numerical procedure for calculating the irreducible 2-loop graphs of the sunset topology is presented. On the other hand, the chiral Lagrangian L^6 produces a direct coupling of the K0 current with the electromagnetic field tensor. Due to this coupling one of the unknown parameters of L^6 occurs in the contribution to the K0 charge radius.
[ { "created": "Tue, 11 Jul 2000 10:08:14 GMT", "version": "v1" }, { "created": "Wed, 11 Oct 2000 12:23:31 GMT", "version": "v2" } ]
2009-10-31
[ [ "Post", "P.", "" ], [ "Schilcher", "K.", "" ] ]
This paper describes the calculation of the electromagnetic form factor of the K0 meson at order p^6 of chiral perturbation theory which is the next-to-leading order correction to the well-known p^4 result achieved by Gasser and Leutwyler. On the one hand, at order p^6 the chiral expansion contains 1- and 2-loop diagrams which are discussed in detail. Especially, a numerical procedure for calculating the irreducible 2-loop graphs of the sunset topology is presented. On the other hand, the chiral Lagrangian L^6 produces a direct coupling of the K0 current with the electromagnetic field tensor. Due to this coupling one of the unknown parameters of L^6 occurs in the contribution to the K0 charge radius.
hep-ph/9802262
Oleg Veretin
J. Fleischer (Bielefeld University), M.Yu. Kalmykov (JINR, Dubna) and O.L. Veretin (Bielefeld University)
Large Mass Expansion versus Small Momentum Expansion of Feynman Diagrams
LaTeX, 8 pages including 5 eps figures, uses epsf.sty
Phys.Lett. B427 (1998) 141-146
10.1016/S0370-2693(98)00312-8
BI-TP-97/43
hep-ph
null
The method of the large mass expansion (LME) has the technical advantage that two-loop integrals occur only as bubbles with large masses. In many cases only one large mass occurs. In such cases these integrals are expressible in terms of $\Gamma$-functions, i.e. they can be handled completely analytically avoiding even recursions and therefore this approach may find a wide field of application. We consider it necessary to investigate the precision of this method and test it for several two-loop vertex functions ocurring in the $Z \to b\bar{b}$ decay by comparing it with the small momentum expansion. It turns out that in general high order approximants have to be taken into account for a sufficient accuracy.
[ { "created": "Fri, 6 Feb 1998 13:01:40 GMT", "version": "v1" } ]
2009-10-31
[ [ "Fleischer", "J.", "", "Bielefeld University" ], [ "Kalmykov", "M. Yu.", "", "JINR, Dubna" ], [ "Veretin", "O. L.", "", "Bielefeld University" ] ]
The method of the large mass expansion (LME) has the technical advantage that two-loop integrals occur only as bubbles with large masses. In many cases only one large mass occurs. In such cases these integrals are expressible in terms of $\Gamma$-functions, i.e. they can be handled completely analytically avoiding even recursions and therefore this approach may find a wide field of application. We consider it necessary to investigate the precision of this method and test it for several two-loop vertex functions ocurring in the $Z \to b\bar{b}$ decay by comparing it with the small momentum expansion. It turns out that in general high order approximants have to be taken into account for a sufficient accuracy.
1403.6830
Matthew McCullough
Patrick J. Fox, Yonatan Kahn, and Matthew McCullough
Taking Halo-Independent Dark Matter Methods Out of the Bin
18 pages, 3 figures. v2 updated to match published version
null
10.1088/1475-7516/2014/10/076
FERMILAB-PUB-14-004-T, MIT-CTP-4528
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We develop a new halo-independent strategy for analyzing emerging DM hints, utilizing the method of extended maximum likelihood. This approach does not require the binning of events, making it uniquely suited to the analysis of emerging DM direct detection hints. It determines a preferred envelope, at a given confidence level, for the DM velocity integral which best fits the data using all available information and can be used even in the case of a single anomalous scattering event. All of the halo-independent information from a direct detection result may then be presented in a single plot, allowing simple comparisons between multiple experiments. This results in the halo-independent analogue of the usual mass and cross-section plots found in typical direct detection analyses, where limit curves may be compared with best-fit regions in halo-space. The method is straightforward to implement, using already-established techniques, and its utility is demonstrated through the first unbinned halo-independent comparison of the three anomalous events observed in the CDMS-Si detector with recent limits from the LUX experiment.
[ { "created": "Wed, 26 Mar 2014 20:00:01 GMT", "version": "v1" }, { "created": "Thu, 11 Jun 2015 18:46:15 GMT", "version": "v2" } ]
2015-06-19
[ [ "Fox", "Patrick J.", "" ], [ "Kahn", "Yonatan", "" ], [ "McCullough", "Matthew", "" ] ]
We develop a new halo-independent strategy for analyzing emerging DM hints, utilizing the method of extended maximum likelihood. This approach does not require the binning of events, making it uniquely suited to the analysis of emerging DM direct detection hints. It determines a preferred envelope, at a given confidence level, for the DM velocity integral which best fits the data using all available information and can be used even in the case of a single anomalous scattering event. All of the halo-independent information from a direct detection result may then be presented in a single plot, allowing simple comparisons between multiple experiments. This results in the halo-independent analogue of the usual mass and cross-section plots found in typical direct detection analyses, where limit curves may be compared with best-fit regions in halo-space. The method is straightforward to implement, using already-established techniques, and its utility is demonstrated through the first unbinned halo-independent comparison of the three anomalous events observed in the CDMS-Si detector with recent limits from the LUX experiment.
hep-ph/0305200
Noriyuki Oshimo
Noriyuki Oshimo
Masses and mixing of neutrinos in grand unified SO(10) model
2 pages, To be published in the Proceedings of the 1st International Symposium on New Developments of Integrated Sciences, Tokyo, Japan, 11,13,14 March, 2003
null
null
OCHA-PP-205
hep-ph
null
A grand unified model based on SO(10) and supersymmetry is presented to account for the masses and mixing of the neutrinos observed in experiments.
[ { "created": "Sun, 18 May 2003 14:44:40 GMT", "version": "v1" } ]
2007-05-23
[ [ "Oshimo", "Noriyuki", "" ] ]
A grand unified model based on SO(10) and supersymmetry is presented to account for the masses and mixing of the neutrinos observed in experiments.
hep-ph/0207146
null
D. Metaxas (Athens, Tech. U.)
Hard thermal loops with a background plasma velocity
11 pages, no figures
Europhys.Lett.61:599-605,2003
10.1209/epl/i2003-00113-x
null
hep-ph
null
I consider the calculation of the two and three-point functions for QED at finite temperature in the presence of a background plasma velocity. The final expressions are consistent with Lorentz invariance, gauge invariance and current conservation, pointing to a straightforward generalization of the hard thermal loop formalism to this physical situation. I also give the resulting expression for the effective action and identify the various terms.
[ { "created": "Thu, 11 Jul 2002 13:12:39 GMT", "version": "v1" } ]
2010-12-17
[ [ "Metaxas", "D.", "", "Athens, Tech. U." ] ]
I consider the calculation of the two and three-point functions for QED at finite temperature in the presence of a background plasma velocity. The final expressions are consistent with Lorentz invariance, gauge invariance and current conservation, pointing to a straightforward generalization of the hard thermal loop formalism to this physical situation. I also give the resulting expression for the effective action and identify the various terms.
1304.4193
David Eby
David A. Eby
Binary Tetrahedral Flavor Symmetry
PhD thesis, University of North Carolina at Chapel Hill, April 2013
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A study of the T' Model and its variants utilizing Binary Tetrahedral Flavor Symmetry. We begin with a description of the historical context and motivations for this theory, together with some conceptual background for added clarity, and an account of our theory's inception in previous works. Our model endeavors to bridge two categories of particles, leptons and quarks, a unification made possible by the inclusion of additional Higgs particles, shared between the two fermion sectors and creating a single coherent system. This is achieved through the use of the Binary Tetrahedral symmetry group and an investigation of the Tribimaximal symmetry evidenced by neutrinos. Our work details perturbations and extensions of this T' Model as we apply our framework to neutrino mixing, quark mixing, unification, and dark matter. Where possible, we evaluate model predictions against experimental results and find excellent matching with the atmospheric and reactor neutrino mixing angles, an accurate prediction of the Cabibbo angle, and a dark matter candidate that remains outside the limits of current tests. Additionally, we include mention of a number of unanswered questions and remaining areas of interest for future study. Taken together, we believe these results speak to the promising potential of finite groups and flavor symmetries to act as an approximation of nature.
[ { "created": "Mon, 15 Apr 2013 18:17:31 GMT", "version": "v1" } ]
2013-04-16
[ [ "Eby", "David A.", "" ] ]
A study of the T' Model and its variants utilizing Binary Tetrahedral Flavor Symmetry. We begin with a description of the historical context and motivations for this theory, together with some conceptual background for added clarity, and an account of our theory's inception in previous works. Our model endeavors to bridge two categories of particles, leptons and quarks, a unification made possible by the inclusion of additional Higgs particles, shared between the two fermion sectors and creating a single coherent system. This is achieved through the use of the Binary Tetrahedral symmetry group and an investigation of the Tribimaximal symmetry evidenced by neutrinos. Our work details perturbations and extensions of this T' Model as we apply our framework to neutrino mixing, quark mixing, unification, and dark matter. Where possible, we evaluate model predictions against experimental results and find excellent matching with the atmospheric and reactor neutrino mixing angles, an accurate prediction of the Cabibbo angle, and a dark matter candidate that remains outside the limits of current tests. Additionally, we include mention of a number of unanswered questions and remaining areas of interest for future study. Taken together, we believe these results speak to the promising potential of finite groups and flavor symmetries to act as an approximation of nature.
1511.06898
Andrei Kataev
A.L. Kataev and V.S. Molokoedov
On the flavour dependence of the $\mathcal{O}(\alpha_s^4)$ correction to the relation between running and pole heavy quark masses
Text a bit modified. Additioinal discusions in favor of the results obtained are added in Note Added; extra references added; Modified INR-TH-2015-014 preprint, accepted for publication in Euro Phys. J. Plus
null
null
null
hep-ph hep-ex hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Recently the four-loop perturbative QCD contributions to the relations between pole and running masses of charm, bottom and top quarks were evaluated in the $\rm{\overline{MS}}$-scheme with identical numerical error bars. In this work the flavour dependence of the $\mathcal{O}(\alpha_s^4)$ correction to these asymptotic series is obtained in the semi-analytical form with the help of the least squares method. The numerical structure of the corresponding asymptotic perturbative relations between pole and running $c$, $b$ and $t$-quark masses is considered and the theoretical errors of the $\mathcal{O}(\alpha_s^4)$-contributions are discussed. The explicit dependence for these relations on the renormalization scale $\mu^2$ and the flavour number $n_l$ is presented.
[ { "created": "Sat, 21 Nov 2015 16:59:13 GMT", "version": "v1" }, { "created": "Fri, 11 Mar 2016 15:44:52 GMT", "version": "v2" }, { "created": "Tue, 10 May 2016 15:38:11 GMT", "version": "v3" }, { "created": "Mon, 11 Jul 2016 18:44:29 GMT", "version": "v4" } ]
2016-07-18
[ [ "Kataev", "A. L.", "" ], [ "Molokoedov", "V. S.", "" ] ]
Recently the four-loop perturbative QCD contributions to the relations between pole and running masses of charm, bottom and top quarks were evaluated in the $\rm{\overline{MS}}$-scheme with identical numerical error bars. In this work the flavour dependence of the $\mathcal{O}(\alpha_s^4)$ correction to these asymptotic series is obtained in the semi-analytical form with the help of the least squares method. The numerical structure of the corresponding asymptotic perturbative relations between pole and running $c$, $b$ and $t$-quark masses is considered and the theoretical errors of the $\mathcal{O}(\alpha_s^4)$-contributions are discussed. The explicit dependence for these relations on the renormalization scale $\mu^2$ and the flavour number $n_l$ is presented.