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0909.0947
Aneesh Manohar
Jui-yu Chiu, Andreas Fuhrer, Randall Kelley, and Aneesh V. Manohar
Soft and Collinear Functions for the Standard Model
23 pages, 12 figures. Typos fixed. Lepton collinear function plot included
Phys.Rev.D81:014023,2010
10.1103/PhysRevD.81.014023
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Radiative corrections to high energy scattering processes were given previously in terms of universal soft and collinear functions. This paper gives the collinear functions for all standard model particles, the general form of the soft function, and explicit expressions for the soft functions for fermion-fermion scattering, longitudinal and transverse gauge boson production, single W/Z production, and associated Higgs production. An interesting subtlety in the use of the Goldstone boson equivalence theorem for longitudinal W+ production is discussed.
[ { "created": "Mon, 7 Sep 2009 15:53:45 GMT", "version": "v1" }, { "created": "Tue, 22 Sep 2009 15:43:06 GMT", "version": "v2" } ]
2010-04-06
[ [ "Chiu", "Jui-yu", "" ], [ "Fuhrer", "Andreas", "" ], [ "Kelley", "Randall", "" ], [ "Manohar", "Aneesh V.", "" ] ]
Radiative corrections to high energy scattering processes were given previously in terms of universal soft and collinear functions. This paper gives the collinear functions for all standard model particles, the general form of the soft function, and explicit expressions for the soft functions for fermion-fermion scattering, longitudinal and transverse gauge boson production, single W/Z production, and associated Higgs production. An interesting subtlety in the use of the Goldstone boson equivalence theorem for longitudinal W+ production is discussed.
hep-ph/0004053
K. Sridhar
K. Sridhar (TIFR)
Large Extra Dimensions at Linear Colliders
Talk given at the Third International Workshop on Electron-Electron Interactions at TeV Energies (e- e- 99), Santa Cruz, California, 10-12 Dec 1999. 7 pages, LaTeX, style files attached
Int.J.Mod.Phys.A15:2397-2404,2000
10.1142/S0217751X00002469
TIFR/TH/16
hep-ph
null
In this talk, I first present the motivation for theories wherein extra spacetime dimensions can be compactified to have large magnitudes. In particular, I discuss the Arkani-Hamed, Dimopoulos, Dvali (ADD) scenario. I present the constraints that have been derived on these models from current experiments and the expectations from future colliders. I concentrate particularly on the possibilities of probing these extra dimensions at future linear colliders.
[ { "created": "Thu, 6 Apr 2000 12:04:39 GMT", "version": "v1" } ]
2015-06-25
[ [ "Sridhar", "K.", "", "TIFR" ] ]
In this talk, I first present the motivation for theories wherein extra spacetime dimensions can be compactified to have large magnitudes. In particular, I discuss the Arkani-Hamed, Dimopoulos, Dvali (ADD) scenario. I present the constraints that have been derived on these models from current experiments and the expectations from future colliders. I concentrate particularly on the possibilities of probing these extra dimensions at future linear colliders.
1506.04481
Su-Kyeong Lee
Jeong Hun Yang, Su Kyeong Lee, Eun-Joo Kim and Jong Bum Choi
Analysis of $X$ Particle Spectra in Quarkonium Model
16 pages, 3 figures, 7 tables
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Three more $X$ particles are established in the 2014 Particle Data compared with the 2012 ones. There are now five established $X$ particles named as $X(3872)$, $X(3900)$, $X(4260)$, $X(4360)$, and $X(4660)$. Since the first $X$ particle $X(3872)$ was discovered during the search for the remaining P charmonium states, it is valuable to check whether the established $X$ particles can be explained by quarkonium model. In this paper, we try to calculate the mass spectra of charmonium system by considering spin-dependent forces deduced from one gluon exchange diagrams. The confining potential form is taken to be linear and the free parameters are determined by least squares method comparing the theoretical and the observed masses of charmonium states.
[ { "created": "Mon, 15 Jun 2015 05:33:33 GMT", "version": "v1" } ]
2015-06-16
[ [ "Yang", "Jeong Hun", "" ], [ "Lee", "Su Kyeong", "" ], [ "Kim", "Eun-Joo", "" ], [ "Choi", "Jong Bum", "" ] ]
Three more $X$ particles are established in the 2014 Particle Data compared with the 2012 ones. There are now five established $X$ particles named as $X(3872)$, $X(3900)$, $X(4260)$, $X(4360)$, and $X(4660)$. Since the first $X$ particle $X(3872)$ was discovered during the search for the remaining P charmonium states, it is valuable to check whether the established $X$ particles can be explained by quarkonium model. In this paper, we try to calculate the mass spectra of charmonium system by considering spin-dependent forces deduced from one gluon exchange diagrams. The confining potential form is taken to be linear and the free parameters are determined by least squares method comparing the theoretical and the observed masses of charmonium states.
hep-ph/0102048
Massimo Blasone
Massimo Blasone, Antonio Capolupo, Oreste Romei, Giuseppe Vitiello
Quantum Field Theory of boson mixing
13 pages, 6 figures, RevTeX
Phys.Rev. D63 (2001) 125015
10.1103/PhysRevD.63.125015
null
hep-ph
null
We consider the quantum field theoretical formulation of boson field mixing and obtain the exact oscillation formula. This formula does not depend on arbitrary mass parameters. We show that the space for the mixed field states is unitarily inequivalent to the state space where the unmixed field operators are defined. We also study the structure of the currents and charges for the mixed fields.
[ { "created": "Mon, 5 Feb 2001 18:13:33 GMT", "version": "v1" } ]
2009-11-07
[ [ "Blasone", "Massimo", "" ], [ "Capolupo", "Antonio", "" ], [ "Romei", "Oreste", "" ], [ "Vitiello", "Giuseppe", "" ] ]
We consider the quantum field theoretical formulation of boson field mixing and obtain the exact oscillation formula. This formula does not depend on arbitrary mass parameters. We show that the space for the mixed field states is unitarily inequivalent to the state space where the unmixed field operators are defined. We also study the structure of the currents and charges for the mixed fields.
1205.0757
Elvio Di Salvo
Z. J. Ajaltouni and E. Di Salvo
Interference Effects, Time Reversal Violation and Search for New Physics in Hadronic Weak Decays
35 pages
International Journal of Modern Physics A 27 (2012) 1250086
10.1142/S0217751X12500868
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose some methods for studying hadronic sequential two-body decays involving more spinning particles. It relies on the analysis of T-odd and T-even asymmetries, which are related to interference terms. The latter asymmetries turn out to be as useful as the former ones in inferring time reversal violating observables; these in turn may be sensitive, under some particular conditions, to possible contributions beyond the standard model. Our main result is that one can extract such observables even after integrating the differential decay width over almost all of the available angles. Moreover we find that the correlations based exclusively on momenta are quite general, since they provide as much information as those involving one or more spins. We generalize some methods already proposed in the literature for particular decay channels, but we also pick out a new kind of time reversal violating observables. Our analysis could be applied, for example, to data of LHCb experiment.
[ { "created": "Thu, 3 May 2012 16:27:40 GMT", "version": "v1" } ]
2012-06-20
[ [ "Ajaltouni", "Z. J.", "" ], [ "Di Salvo", "E.", "" ] ]
We propose some methods for studying hadronic sequential two-body decays involving more spinning particles. It relies on the analysis of T-odd and T-even asymmetries, which are related to interference terms. The latter asymmetries turn out to be as useful as the former ones in inferring time reversal violating observables; these in turn may be sensitive, under some particular conditions, to possible contributions beyond the standard model. Our main result is that one can extract such observables even after integrating the differential decay width over almost all of the available angles. Moreover we find that the correlations based exclusively on momenta are quite general, since they provide as much information as those involving one or more spins. We generalize some methods already proposed in the literature for particular decay channels, but we also pick out a new kind of time reversal violating observables. Our analysis could be applied, for example, to data of LHCb experiment.
hep-ph/9711515
David Ward
David Ward (Cavendish Laboratory, University of Cambridge)
Tests of the Standard Model: W mass and WWZ Couplings
14 Pages. 12 figures. Review talk at the International Europhysics Conference on High Energy Physics, Jerusalem, 19-26 August 1997
null
null
null
hep-ph
null
Recent tests of the electroweak Standard Model are reviewed, covering the precise measurements of Z decays at LEP I and SLC and measurements of fermion pair production at higher energies at LEP II. Special emphasis is given to new results on W physics from LEP and FNAL.
[ { "created": "Fri, 28 Nov 1997 16:56:15 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ward", "David", "", "Cavendish Laboratory, University of Cambridge" ] ]
Recent tests of the electroweak Standard Model are reviewed, covering the precise measurements of Z decays at LEP I and SLC and measurements of fermion pair production at higher energies at LEP II. Special emphasis is given to new results on W physics from LEP and FNAL.
1001.5398
Pasquini Barbara
B. Pasquini (Pavia U. & INFN, Pavia) and F. Yuan (LBL, Berkeley & Riken BNL)
Sivers and Boer-Mulders functions in Light-Cone Quark Models
references and explanations added; version to appear in Phys. Rev. D
Phys.Rev.D81:114013,2010
10.1103/PhysRevD.81.114013
null
hep-ph hep-ex hep-th nucl-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Results for the naive-time-reversal-odd quark distributions in a light-cone quark model are presented. The final-state interaction effects are generated via single-gluon exchange mechanism. The formalism of light-cone wave functions is used to derive general expressions in terms of overlap of wave-function amplitudes describing the different orbital angular momentum components of the nucleon. In particular, the model predictions show a dominant contribution from S- and P-wave interference in the Sivers function and a significant contribution also from the interference of P and D waves in the Boer-Mulders function. The favourable comparison with existing phenomenological parametrizations motivates further applications to describe azimuthal asymmetries in hadronic reactions.
[ { "created": "Fri, 29 Jan 2010 13:06:57 GMT", "version": "v1" }, { "created": "Fri, 4 Jun 2010 07:16:53 GMT", "version": "v2" } ]
2014-11-20
[ [ "Pasquini", "B.", "", "Pavia U. & INFN, Pavia" ], [ "Yuan", "F.", "", "LBL, Berkeley &\n Riken BNL" ] ]
Results for the naive-time-reversal-odd quark distributions in a light-cone quark model are presented. The final-state interaction effects are generated via single-gluon exchange mechanism. The formalism of light-cone wave functions is used to derive general expressions in terms of overlap of wave-function amplitudes describing the different orbital angular momentum components of the nucleon. In particular, the model predictions show a dominant contribution from S- and P-wave interference in the Sivers function and a significant contribution also from the interference of P and D waves in the Boer-Mulders function. The favourable comparison with existing phenomenological parametrizations motivates further applications to describe azimuthal asymmetries in hadronic reactions.
1101.3886
Igor Dyatlov Tichonovitch
I. T. Dyatlov
Nonstandard Origin of the Standard Electroweak Currents
20 pages, no figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Implications are considered of the hypothesis that the symplectic group $Sp(n/2)$ is the spontaneously violated gauge group of n lepton flavors. Invariant Majorana masses are impossible in $Sp(n/2)$. For the local gauge symmetry $Sp(n/2)$ the dynamical spontaneous violation is only achievable for the number of flavors $n=6$ with simultaneous parity ($R,L-$symmetry) violation. The see-saw mechanism produces here three light and three heavy Dirac neutrinos. Majorana states are unavailable here. Neglecting heavy particles in the $R,L-$symmetric system of weak and electromagnetic interactions ($R,L-$independent values of isospins Tw and hypercharges $Y$ for leptons or quarks) leads to a theory with parity nonconservation and axial anomalies. Only weak left $(L)$ and full $(R+L)$ electromagnetic currents do not have anomalies and remain independent of the physics of heavy masses. These currents are the ones of the Standard Model. The absence of anomalies merely in the combination of currents forming the electromagnetic one presents essential difference with the SM case, where the both, left $T_W$ and $Y$, currents are deprived of anomalies independently.
[ { "created": "Thu, 20 Jan 2011 12:49:06 GMT", "version": "v1" }, { "created": "Sat, 5 Mar 2011 09:18:45 GMT", "version": "v2" } ]
2011-03-08
[ [ "Dyatlov", "I. T.", "" ] ]
Implications are considered of the hypothesis that the symplectic group $Sp(n/2)$ is the spontaneously violated gauge group of n lepton flavors. Invariant Majorana masses are impossible in $Sp(n/2)$. For the local gauge symmetry $Sp(n/2)$ the dynamical spontaneous violation is only achievable for the number of flavors $n=6$ with simultaneous parity ($R,L-$symmetry) violation. The see-saw mechanism produces here three light and three heavy Dirac neutrinos. Majorana states are unavailable here. Neglecting heavy particles in the $R,L-$symmetric system of weak and electromagnetic interactions ($R,L-$independent values of isospins Tw and hypercharges $Y$ for leptons or quarks) leads to a theory with parity nonconservation and axial anomalies. Only weak left $(L)$ and full $(R+L)$ electromagnetic currents do not have anomalies and remain independent of the physics of heavy masses. These currents are the ones of the Standard Model. The absence of anomalies merely in the combination of currents forming the electromagnetic one presents essential difference with the SM case, where the both, left $T_W$ and $Y$, currents are deprived of anomalies independently.
hep-ph/0606300
Tom\'a\v{s} Brauner
Tomas Brauner
Spontaneous symmetry breaking in strong and electroweak interactions
57 pages, PhD thesis
null
null
null
hep-ph
null
This is the introduction to the PhD thesis, defended in June 2006. In the original form it was appended with the reprints of the author's published papers, and is to be regarded as their summary. Full details may be found in the quoted papers.
[ { "created": "Thu, 29 Jun 2006 11:25:15 GMT", "version": "v1" } ]
2007-05-23
[ [ "Brauner", "Tomas", "" ] ]
This is the introduction to the PhD thesis, defended in June 2006. In the original form it was appended with the reprints of the author's published papers, and is to be regarded as their summary. Full details may be found in the quoted papers.
hep-ph/0202014
Masahiro Kawasaki
Masahiro Kawasaki
Moduli problem and Q-ball baryogenesis in gauge-mediated SUSY breaking models
12pages, 3 figures, Proceedings of COSMO-01 Rovaniemi
null
null
null
hep-ph
null
We investigate whether the Affleck-Dine mechanism can produce sufficient baryon number of the universe in the gauge-mediated SUSY breaking models, while evading the cosmological moduli problem by late-time entropy production. We find that the Q-ball formation makes the scenario difficult, irrespective of the detail mechanism of the entropy production.
[ { "created": "Mon, 4 Feb 2002 06:12:58 GMT", "version": "v1" } ]
2007-05-23
[ [ "Kawasaki", "Masahiro", "" ] ]
We investigate whether the Affleck-Dine mechanism can produce sufficient baryon number of the universe in the gauge-mediated SUSY breaking models, while evading the cosmological moduli problem by late-time entropy production. We find that the Q-ball formation makes the scenario difficult, irrespective of the detail mechanism of the entropy production.
1511.02477
Alexei P. Martynenko
A.V. Eskin, R.N. Faustov, A.P. Martynenko, F.A. Martynenko
Hadronic deuteron polarizability contribution to the Lamb shift in muonic deuterium
12 pages, 2 figures
Mod. Phys. Lett. A, Vol. 31, No. 18 (2016) 1650104
10.1142/S0217732316501042
SSU-HEP-15/11
hep-ph quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Hadronic deuteron polarizability correction to the Lamb shift of muonic deuterium is calculated on the basis of unitary isobar model and modern experimental data on the structure functions of deep inelastic lepton-deuteron scattering and their parameterizations in the resonance and nonresonance regions.
[ { "created": "Sun, 8 Nov 2015 12:43:46 GMT", "version": "v1" }, { "created": "Sun, 3 Jan 2016 18:41:38 GMT", "version": "v2" }, { "created": "Sun, 28 Feb 2016 19:22:11 GMT", "version": "v3" } ]
2016-06-14
[ [ "Eskin", "A. V.", "" ], [ "Faustov", "R. N.", "" ], [ "Martynenko", "A. P.", "" ], [ "Martynenko", "F. A.", "" ] ]
Hadronic deuteron polarizability correction to the Lamb shift of muonic deuterium is calculated on the basis of unitary isobar model and modern experimental data on the structure functions of deep inelastic lepton-deuteron scattering and their parameterizations in the resonance and nonresonance regions.
hep-ph/0409176
Nikolaos Stefanis
N. G. Stefanis, A. P. Bakulev, S. V. Mikhailov, K. Passek-Kumeri\v{c}ki, W. Schroers
Pion structure: from nonlocal condensates to NLO analytic perturbation theory
9 pages, 4 figures consisting of 6 eps files. Needs hsqcd.cls. Invited plenary talk presented by the first author at Hadron Structure and QCD: from Low to High Energies, St. Petersburg, Repino, Russia, 18-22 May 2004
null
null
RUB-TPII-04/04
hep-ph
null
A pion distribution amplitude, derived from nonlocal QCD sum rules, has been employed to calculate $F_{\gamma^*\gamma\to\pi}(Q^2)$ using light-cone sum rules, and $F_{\pi}(Q^2)$ in NLO QCD perturbation theory. Predictions are presented for both observables and found to be in good agreement with the corresponding data. Calculating the hard pion form factor by Analytic Perturbation Theory to two-loop order, it is shown that the renormalization-scheme and scale-setting dependencies are diminished.
[ { "created": "Wed, 15 Sep 2004 17:41:43 GMT", "version": "v1" } ]
2007-05-23
[ [ "Stefanis", "N. G.", "" ], [ "Bakulev", "A. P.", "" ], [ "Mikhailov", "S. V.", "" ], [ "Passek-Kumerički", "K.", "" ], [ "Schroers", "W.", "" ] ]
A pion distribution amplitude, derived from nonlocal QCD sum rules, has been employed to calculate $F_{\gamma^*\gamma\to\pi}(Q^2)$ using light-cone sum rules, and $F_{\pi}(Q^2)$ in NLO QCD perturbation theory. Predictions are presented for both observables and found to be in good agreement with the corresponding data. Calculating the hard pion form factor by Analytic Perturbation Theory to two-loop order, it is shown that the renormalization-scheme and scale-setting dependencies are diminished.
hep-ph/9711280
Mikolaj Misiak
Konstantin Chetyrkin, Mikolaj Misiak and Manfred Muenz
|Delta F| = 1 Nonleptonic Effective Hamiltonian in a Simpler Scheme
21 pages, 7 figures, uses epsf.sty
Nucl.Phys.B520:279-297,1998
10.1016/S0550-3213(98)00131-X
MPI/PhT/97-51, TTP97-44, ZU-TH-17/97, TUM-HEP-285/97, IFT-12/97
hep-ph
null
We consider |\Delta F| = 1 (F = S,C or B) nonleptonic effective hamiltonian in a renormalization scheme which allows to consistently use fully anticommuting gamma_5 at any number of loops, but at the leading order in the Fermi coupling G_F. We calculate two-loop anomalous dimensions and one-loop matching conditions for the effective operators in this scheme. Finally, we transform our results to one of the previously used renormalization schemes, and find agreement with the original calculations.
[ { "created": "Mon, 10 Nov 1997 21:52:33 GMT", "version": "v1" } ]
2011-01-27
[ [ "Chetyrkin", "Konstantin", "" ], [ "Misiak", "Mikolaj", "" ], [ "Muenz", "Manfred", "" ] ]
We consider |\Delta F| = 1 (F = S,C or B) nonleptonic effective hamiltonian in a renormalization scheme which allows to consistently use fully anticommuting gamma_5 at any number of loops, but at the leading order in the Fermi coupling G_F. We calculate two-loop anomalous dimensions and one-loop matching conditions for the effective operators in this scheme. Finally, we transform our results to one of the previously used renormalization schemes, and find agreement with the original calculations.
hep-ph/0402023
Maxim Pospelov
Oleg Lebedev, Keith A. Olive, Maxim Pospelov and Adam Ritz
Probing CP Violation with the Deuteron Electric Dipole Moment
5 pages, 4 figures; precision estimates clarified, to appear in Phys. Rev. D
Phys.Rev.D70:016003,2004
10.1103/PhysRevD.70.016003
UVIC-TH-03-10, DESY 04-020, CERN-PH-TH/2004-017, UMN-TH-2229/04
hep-ph nucl-th
null
We present an analysis of the electric dipole moment (EDM) of the deuteron as induced by CP-violating operators of dimension 4, 5 and 6 including theta QCD, the EDMs and color EDMs of quarks, four-quark interactions and the Weinberg operator. We demonstrate that the precision goal of the EDM Collaboration's proposal to search for the deuteron EDM, (1-3)\times 10^{-27} e cm, will provide an improvement in sensitivity to these sources of one-two orders of magnitude relative to the existing bounds. We consider in detail the level to which CP-odd phases can be probed within the MSSM.
[ { "created": "Mon, 2 Feb 2004 19:04:42 GMT", "version": "v1" }, { "created": "Tue, 4 May 2004 08:46:18 GMT", "version": "v2" } ]
2008-11-26
[ [ "Lebedev", "Oleg", "" ], [ "Olive", "Keith A.", "" ], [ "Pospelov", "Maxim", "" ], [ "Ritz", "Adam", "" ] ]
We present an analysis of the electric dipole moment (EDM) of the deuteron as induced by CP-violating operators of dimension 4, 5 and 6 including theta QCD, the EDMs and color EDMs of quarks, four-quark interactions and the Weinberg operator. We demonstrate that the precision goal of the EDM Collaboration's proposal to search for the deuteron EDM, (1-3)\times 10^{-27} e cm, will provide an improvement in sensitivity to these sources of one-two orders of magnitude relative to the existing bounds. We consider in detail the level to which CP-odd phases can be probed within the MSSM.
hep-ph/0003063
Ryuichiro Kitano
Ryuichiro Kitano and Katsuji Yamamoto
Lepton flavor violation in the supersymmetric standard model with vectorlike leptons
25 pages, 5 figures, comments about K0-K0bar mixing added
Phys.Rev. D62 (2000) 073007
10.1103/PhysRevD.62.073007
KEK-TH-681
hep-ph
null
Lepton flavor violating processes are obtained from the mixing between ordinary leptons and vectorlike SU(2)_L doublet leptons which may originate in E_6. The effects of this lepton mixing are, however, suppressed naturally by the hierarchy of the charged lepton masses. In the supersymmetric model, significant effects of lepton flavor violation may appear rather through slepton mixing, which is in the present case generated by radiative corrections with ordinary-exotic lepton couplings. We are especially interested in the mu -> e gamma decay. In the model without the bare mass term of vectorlike leptons, the supersymmetric contributions are rather suppressed due to the approximate U(1)_e X U(1)_mu. It is, however, remarkable that they are substantially enhanced by tan^6 beta. Then, B(mu -> e gamma) might be comparable to the experimental bound for large tan beta. In the model with the bare mass term, much larger contributions are obtained through slepton mixing. These investigations show that the supersymmetric effects on lepton flavor violation due to the vectorlike leptons can be observed in the near future experiments.
[ { "created": "Wed, 8 Mar 2000 11:03:12 GMT", "version": "v1" }, { "created": "Mon, 28 Aug 2000 05:47:29 GMT", "version": "v2" } ]
2009-10-31
[ [ "Kitano", "Ryuichiro", "" ], [ "Yamamoto", "Katsuji", "" ] ]
Lepton flavor violating processes are obtained from the mixing between ordinary leptons and vectorlike SU(2)_L doublet leptons which may originate in E_6. The effects of this lepton mixing are, however, suppressed naturally by the hierarchy of the charged lepton masses. In the supersymmetric model, significant effects of lepton flavor violation may appear rather through slepton mixing, which is in the present case generated by radiative corrections with ordinary-exotic lepton couplings. We are especially interested in the mu -> e gamma decay. In the model without the bare mass term of vectorlike leptons, the supersymmetric contributions are rather suppressed due to the approximate U(1)_e X U(1)_mu. It is, however, remarkable that they are substantially enhanced by tan^6 beta. Then, B(mu -> e gamma) might be comparable to the experimental bound for large tan beta. In the model with the bare mass term, much larger contributions are obtained through slepton mixing. These investigations show that the supersymmetric effects on lepton flavor violation due to the vectorlike leptons can be observed in the near future experiments.
2011.06599
Cari Cesarotti
Cari Cesarotti, Matthew Reece, Matthew J. Strassler
The Efficacy of Event Isotropy as an Event Shape Observable
31 pages, 19 figures
null
10.1007/JHEP07(2021)215
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Event isotropy $\mathcal{I}^\text{sph}$, an event shape observable that measures the distance of a final state from a spherically symmetric state, is designed for new physics signals that are far from QCD-like. Using a new technique for producing a wide variety of signals that can range from near-spherical to jetty, we compare event isotropy to other observables. We show that thrust $T$ and the $C$ parameter (and $\lambda_\text{max}$, the largest eigenvalue of the sphericity matrix) are strongly correlated and thus redundant, to a good approximation. By contrast, event isotropy adds considerable information, often serving to break degeneracies between signals that would have almost identical $T$ and $C$ distributions. Signals with broad distributions in $T$ (or $\lambda_\text{max}$) and in $\mathcal{I}^\text{sph}$ separately often have much narrower distributions, and are more easily distinguished, in the $({\mathcal{I}^\text{sph}},\lambda_\text{max})$ plane. An intuitive, semi-analytic estimation technique clarifies why this is the case and assists with the interpretation of the distributions.
[ { "created": "Thu, 12 Nov 2020 19:00:00 GMT", "version": "v1" } ]
2021-08-18
[ [ "Cesarotti", "Cari", "" ], [ "Reece", "Matthew", "" ], [ "Strassler", "Matthew J.", "" ] ]
Event isotropy $\mathcal{I}^\text{sph}$, an event shape observable that measures the distance of a final state from a spherically symmetric state, is designed for new physics signals that are far from QCD-like. Using a new technique for producing a wide variety of signals that can range from near-spherical to jetty, we compare event isotropy to other observables. We show that thrust $T$ and the $C$ parameter (and $\lambda_\text{max}$, the largest eigenvalue of the sphericity matrix) are strongly correlated and thus redundant, to a good approximation. By contrast, event isotropy adds considerable information, often serving to break degeneracies between signals that would have almost identical $T$ and $C$ distributions. Signals with broad distributions in $T$ (or $\lambda_\text{max}$) and in $\mathcal{I}^\text{sph}$ separately often have much narrower distributions, and are more easily distinguished, in the $({\mathcal{I}^\text{sph}},\lambda_\text{max})$ plane. An intuitive, semi-analytic estimation technique clarifies why this is the case and assists with the interpretation of the distributions.
0910.3704
Eric S. Swanson
E.S. Swanson
Hadron Spectroscopy -- Theory
To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C090726. Additional references added
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A brief review of theoretical progress in hadron spectroscopy and nonperturbative QCD is presented. Attention is focussed on recent lattice gauge theory, the Dyson-Schwinger formalism, effective field theory, unquenching constituent models, and some beyond the Standard Model physics.
[ { "created": "Mon, 19 Oct 2009 21:21:04 GMT", "version": "v1" }, { "created": "Fri, 30 Oct 2009 17:57:04 GMT", "version": "v2" } ]
2009-10-30
[ [ "Swanson", "E. S.", "" ] ]
A brief review of theoretical progress in hadron spectroscopy and nonperturbative QCD is presented. Attention is focussed on recent lattice gauge theory, the Dyson-Schwinger formalism, effective field theory, unquenching constituent models, and some beyond the Standard Model physics.
hep-ph/9704440
Leonid Burakovsky
L. Burakovsky, T. Goldman and L.P. Horwitz
New Mass Relations for Heavy Quarkonia
10 pages, LaTeX
Phys.Rev.D56:7119-7123,1997
10.1103/PhysRevD.56.7119
LA-UR-97-1494
hep-ph
null
By assuming the existence of (quasi)-linear Regge trajectories for heavy quarkonia in the low energy region, we derive a new, sixth power, meson mass relation which shows good agreement with experiment for both charmed and beauty mesons. This relation may be reduced to a quadratic Gell-Mann-Okubo type formula by fitting the values of the Regge slopes of these (quasi)-linear trajectories. For charmed mesons, such a formula holds with an accuracy of $\sim 1$%, and is in qualitative agreement with the relation obtained previously by the application of the linear spectrum to a meson hexadecuplet.
[ { "created": "Tue, 29 Apr 1997 18:21:45 GMT", "version": "v1" } ]
2008-11-26
[ [ "Burakovsky", "L.", "" ], [ "Goldman", "T.", "" ], [ "Horwitz", "L. P.", "" ] ]
By assuming the existence of (quasi)-linear Regge trajectories for heavy quarkonia in the low energy region, we derive a new, sixth power, meson mass relation which shows good agreement with experiment for both charmed and beauty mesons. This relation may be reduced to a quadratic Gell-Mann-Okubo type formula by fitting the values of the Regge slopes of these (quasi)-linear trajectories. For charmed mesons, such a formula holds with an accuracy of $\sim 1$%, and is in qualitative agreement with the relation obtained previously by the application of the linear spectrum to a meson hexadecuplet.
hep-ph/9912340
Sharon Jensen
Stanley J. Brodsky
New Directions in Quantum Chromodynamics
Invited talk at International Summer School on Particle Production Spanning MeV and TeV Energies (Nijmegen 99), August 1999
null
null
SLAC-PUB-8315
hep-ph
null
Several topics in QCD are reviewed, including: the light-cone Fock state representation, which encodes the flavor, spin and other quark and gluon correlations of hadrons in the form of universal process-independent amplitudes; the light-cone factorization scheme for inclusive and exclusive processes; the application of the light-cone formalism to semi-leptonic B decay amplitudes; self-resolving diffractive interactions as a tool for measuring light-cone wavefunctions; and the use of conformal symmetry as a template for QCD predictions, such as commensurate scale relations, which relate observable to observable at fixed relative scale without renormalization scale or scheme ambiguities.
[ { "created": "Tue, 14 Dec 1999 16:45:07 GMT", "version": "v1" } ]
2007-05-23
[ [ "Brodsky", "Stanley J.", "" ] ]
Several topics in QCD are reviewed, including: the light-cone Fock state representation, which encodes the flavor, spin and other quark and gluon correlations of hadrons in the form of universal process-independent amplitudes; the light-cone factorization scheme for inclusive and exclusive processes; the application of the light-cone formalism to semi-leptonic B decay amplitudes; self-resolving diffractive interactions as a tool for measuring light-cone wavefunctions; and the use of conformal symmetry as a template for QCD predictions, such as commensurate scale relations, which relate observable to observable at fixed relative scale without renormalization scale or scheme ambiguities.
2302.05719
Rui Zhu
Lei Wang, Jin Min Yang, Yang Zhang, Pengxuan Zhu, Rui Zhu
A concise review on some Higgs-related new physics models in light of current experiments
25 pages, 11 figures, 1 table, an invited review for Universe, published version
null
10.3390/universe9040178
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Higgs boson may serve as a portal to new physics beyond the standard model (BSM) which is implied by theoretical naturalness or experimental anomalies. In this note we briefly survey some Higgs-related BSM physics models, including the low energy SUSY (focusing on the minimal SUSY model), the little Higgs models, the two-Higgs-doublet models and the simplest singlet extensions of the Higgs sector. For each illustrated BSM model, we emphatically elucidate its phenomenological power in explaining current measurements of the muon g-2, the W-boson mass and the dark matter. For the singlet extensions like the xSM and 2HDM+S, we discuss the induced cosmic phase transition and the dark matter relic density as well as the vacuum stability. Finally, we give an outlook.
[ { "created": "Sat, 11 Feb 2023 15:24:31 GMT", "version": "v1" }, { "created": "Thu, 13 Apr 2023 14:05:13 GMT", "version": "v2" } ]
2023-04-14
[ [ "Wang", "Lei", "" ], [ "Yang", "Jin Min", "" ], [ "Zhang", "Yang", "" ], [ "Zhu", "Pengxuan", "" ], [ "Zhu", "Rui", "" ] ]
Higgs boson may serve as a portal to new physics beyond the standard model (BSM) which is implied by theoretical naturalness or experimental anomalies. In this note we briefly survey some Higgs-related BSM physics models, including the low energy SUSY (focusing on the minimal SUSY model), the little Higgs models, the two-Higgs-doublet models and the simplest singlet extensions of the Higgs sector. For each illustrated BSM model, we emphatically elucidate its phenomenological power in explaining current measurements of the muon g-2, the W-boson mass and the dark matter. For the singlet extensions like the xSM and 2HDM+S, we discuss the induced cosmic phase transition and the dark matter relic density as well as the vacuum stability. Finally, we give an outlook.
1708.03528
Markus Diehl
Maarten G. A. Buffing, Markus Diehl and Tomas Kasemets
Transverse momentum in double parton scattering: factorisation, evolution and matching
125 pages, 14 figures. v2: additional discussion, especially in sections 6.2 and 8. v3: added erratum (main body of paper unchanged). v4: corrected mistake in text before equation (I.23)
null
10.1007/JHEP01(2018)044
NIKHEF 2016-028, DESY 17-014
hep-ph
http://creativecommons.org/licenses/by/4.0/
We give a description of double parton scattering with measured transverse momenta in the final state, extending the formalism for factorisation and resummation developed by Collins, Soper and Sterman for the production of colourless particles. After a detailed analysis of their colour structure, we derive and solve evolution equations in rapidity and renormalisation scale for the relevant soft factors and double parton distributions. We show how in the perturbative regime, transverse momentum dependent double parton distributions can be expressed in terms of simpler nonperturbative quantities and compute several of the corresponding perturbative kernels at one-loop accuracy. We then show how the coherent sum of single and double parton scattering can be simplified for perturbatively large transverse momenta, and we discuss to which order resummation can be performed with presently available results. As an auxiliary result, we derive a simple form for the square root factor in the Collins construction of transverse momentum dependent parton distributions.
[ { "created": "Fri, 11 Aug 2017 13:00:25 GMT", "version": "v1" }, { "created": "Wed, 10 Jan 2018 19:36:55 GMT", "version": "v2" }, { "created": "Fri, 7 May 2021 11:52:26 GMT", "version": "v3" }, { "created": "Mon, 14 Jun 2021 08:21:08 GMT", "version": "v4" } ]
2021-06-15
[ [ "Buffing", "Maarten G. A.", "" ], [ "Diehl", "Markus", "" ], [ "Kasemets", "Tomas", "" ] ]
We give a description of double parton scattering with measured transverse momenta in the final state, extending the formalism for factorisation and resummation developed by Collins, Soper and Sterman for the production of colourless particles. After a detailed analysis of their colour structure, we derive and solve evolution equations in rapidity and renormalisation scale for the relevant soft factors and double parton distributions. We show how in the perturbative regime, transverse momentum dependent double parton distributions can be expressed in terms of simpler nonperturbative quantities and compute several of the corresponding perturbative kernels at one-loop accuracy. We then show how the coherent sum of single and double parton scattering can be simplified for perturbatively large transverse momenta, and we discuss to which order resummation can be performed with presently available results. As an auxiliary result, we derive a simple form for the square root factor in the Collins construction of transverse momentum dependent parton distributions.
hep-ph/9704216
Ying Shuqian
S. Ying
Quasiparticles and the quantum fluctuations of local observables
4 pages, RevTex, 1 figures in postscript
null
null
null
hep-ph hep-lat hep-th
null
The role that quasiparticles play in a strong interaction system with spontaneous symmetry breaking is examined. We find, using a non- perturbative cluster decomposition method, that the quasiparticles do not saturate the physical local observables at small distances. The fermion number density serves as a clearcut example. A component due to localized random quantum fluctuations of the order parameter(s) in the vacuum state and the contributions of ``quasiparticles'' corresponding to other local minima of the effective potential is needed. At large distances, the ordinary quasiparticle picture emerges in the response of the system to classical background fields but the above mentioned component acts as a source for them.
[ { "created": "Wed, 2 Apr 1997 03:13:26 GMT", "version": "v1" } ]
2007-05-23
[ [ "Ying", "S.", "" ] ]
The role that quasiparticles play in a strong interaction system with spontaneous symmetry breaking is examined. We find, using a non- perturbative cluster decomposition method, that the quasiparticles do not saturate the physical local observables at small distances. The fermion number density serves as a clearcut example. A component due to localized random quantum fluctuations of the order parameter(s) in the vacuum state and the contributions of ``quasiparticles'' corresponding to other local minima of the effective potential is needed. At large distances, the ordinary quasiparticle picture emerges in the response of the system to classical background fields but the above mentioned component acts as a source for them.
1310.0426
Joao Pulido
Joao Pulido and C.R.Das
Sterile neutrinos in the 3+s scenario and solar data
7 pages, 4 figures, contribution to EPS Conference on High Energy Physics-EPS-HEP2013, 18-24 July 2013, Stockholm, Sweden
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The flatness of the SuperKamiokande neutrino electron scattering spectrum and the apparent downturn of the charged current spectrum in the SNO data which the Large Mixing Angle solution (LMA) to the solar neutrino problem fails to predict are analysed in the context of an extension to the standard electroweak model with light sterile neutrinos. It is found that a sterile neutrino which is quasi degenerate with the active ones with $\Delta m^2_{41}=10^{-5}eV^2$ and mixing $sin\theta_{14}=0.04$ provides a suitable improvement to the LMA data fits.
[ { "created": "Tue, 1 Oct 2013 18:55:44 GMT", "version": "v1" } ]
2013-10-02
[ [ "Pulido", "Joao", "" ], [ "Das", "C. R.", "" ] ]
The flatness of the SuperKamiokande neutrino electron scattering spectrum and the apparent downturn of the charged current spectrum in the SNO data which the Large Mixing Angle solution (LMA) to the solar neutrino problem fails to predict are analysed in the context of an extension to the standard electroweak model with light sterile neutrinos. It is found that a sterile neutrino which is quasi degenerate with the active ones with $\Delta m^2_{41}=10^{-5}eV^2$ and mixing $sin\theta_{14}=0.04$ provides a suitable improvement to the LMA data fits.
hep-ph/9511446
Kaladi Babu
K.S. Babu (IAS) and S.M. Barr (Bartol)
Large neutrino mixing angles in unified theories
16 pages, Plain LaTeX, no figures
Phys.Lett.B381:202-208,1996
10.1016/0370-2693(96)00552-7
IASSNS-HEP 95/100, BA-95-56
hep-ph
null
Typically in unified theories the neutrino mixing angles, like the Cabibbo-Kobayashi-Maskawa (CKM) angles of the quarks, are related to the small mass ratios between fermions of different generations and are therefore quite small. A new approach for explaining the intergenerational mass hierarchies is proposed here which, while giving small CKM angles, naturally leads to neutrino angles of order unity. Such large mixing angles may be required for a resolution of the atmospheric neutrino anomaly and may also be relevant for the solar neutrino puzzle. The mechanism presented here provides a framework in which novel approaches to the fermion mass question can arise. In particular, within this framework a variant of the texture idea allows highly predictive models to be constructed, an illustrative example of which is given. It is shown how the neutrino mixing angles may be completely determined in such schemes.
[ { "created": "Wed, 29 Nov 1995 06:02:33 GMT", "version": "v1" } ]
2011-05-12
[ [ "Babu", "K. S.", "", "IAS" ], [ "Barr", "S. M.", "", "Bartol" ] ]
Typically in unified theories the neutrino mixing angles, like the Cabibbo-Kobayashi-Maskawa (CKM) angles of the quarks, are related to the small mass ratios between fermions of different generations and are therefore quite small. A new approach for explaining the intergenerational mass hierarchies is proposed here which, while giving small CKM angles, naturally leads to neutrino angles of order unity. Such large mixing angles may be required for a resolution of the atmospheric neutrino anomaly and may also be relevant for the solar neutrino puzzle. The mechanism presented here provides a framework in which novel approaches to the fermion mass question can arise. In particular, within this framework a variant of the texture idea allows highly predictive models to be constructed, an illustrative example of which is given. It is shown how the neutrino mixing angles may be completely determined in such schemes.
1112.1559
Jan Uphoff
Jan Uphoff, Oliver Fochler, Zhe Xu, Carsten Greiner
Open heavy flavor at RHIC and LHC in a partonic transport model
6 pages, 6 figures, talk given at the conference Strangeness in Quark Matter 2011, Cracow, Poland
Acta Physica Polonica B Proceedings Supplement vol. 5 (2012) page 555
10.5506/APhysPolBSupp.5.555
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Heavy quarks are a unique probe to study the medium produced in ultra-relativistic heavy ion collisions. Within the partonic transport model Boltzmann approach to multi-parton scatterings (BAMPS) the production, energy loss and elliptic flow of heavy quarks are investigated in 3+1 dimensional simulations of the quark gluon plasma evolution. With only binary interactions between heavy quarks and particles from the medium calculated within perturbative QCD, the results on elliptic flow and the nuclear modification factor are not compatible with experimental data from RHIC and LHC. However, if the binary cross section is multiplied with K=4 both the elliptic flow and the nuclear modification factor are simultaneously described at RHIC and also LHC. Furthermore, preliminary results are presented that the implementation of radiative processes leads to a stronger suppression which agrees well with the measured nuclear modification factor at RHIC without the need of any K factor.
[ { "created": "Wed, 7 Dec 2011 13:51:27 GMT", "version": "v1" } ]
2012-04-20
[ [ "Uphoff", "Jan", "" ], [ "Fochler", "Oliver", "" ], [ "Xu", "Zhe", "" ], [ "Greiner", "Carsten", "" ] ]
Heavy quarks are a unique probe to study the medium produced in ultra-relativistic heavy ion collisions. Within the partonic transport model Boltzmann approach to multi-parton scatterings (BAMPS) the production, energy loss and elliptic flow of heavy quarks are investigated in 3+1 dimensional simulations of the quark gluon plasma evolution. With only binary interactions between heavy quarks and particles from the medium calculated within perturbative QCD, the results on elliptic flow and the nuclear modification factor are not compatible with experimental data from RHIC and LHC. However, if the binary cross section is multiplied with K=4 both the elliptic flow and the nuclear modification factor are simultaneously described at RHIC and also LHC. Furthermore, preliminary results are presented that the implementation of radiative processes leads to a stronger suppression which agrees well with the measured nuclear modification factor at RHIC without the need of any K factor.
2203.09002
Motoo Suzuki
Sudhakantha Girmohanta, Seung J. Lee, Yuichiro Nakai, Motoo Suzuki
A Natural Model of Spontaneous CP Violation
9 pages, 5 figures, model updated, published version
null
10.1007/JHEP12(2022)024
YITP-SB-2022-10
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We examine the possibility of building a natural non-supersymmetric model of spontaneous CP violation equipped with the Nelson-Barr (NB) mechanism to address the strong CP problem. Our approach is to utilize a doubly composite dynamics where the first confinement of the CFT occurs at the scale of spontaneous CP violation (SCPV) and the second confinement at the TeV scale. A holographic dual description of this 4D set-up via a warped extra dimension with three 3-branes provides an explicit realization of this idea.In this model, radiative corrections to the strong CP phase are well under control, and the coincidence of mass scales, which we generally encounter in NB models, is addressed. Our model also provides an explanation to the quark Yukawa hierarchies, and a solution to the gauge hierarchy problem just as in the usual Randall-Sundrum model with the Higgs being localized on the TeV brane.
[ { "created": "Thu, 17 Mar 2022 00:47:05 GMT", "version": "v1" }, { "created": "Fri, 1 Apr 2022 08:43:49 GMT", "version": "v2" }, { "created": "Thu, 24 Nov 2022 00:13:19 GMT", "version": "v3" } ]
2022-12-28
[ [ "Girmohanta", "Sudhakantha", "" ], [ "Lee", "Seung J.", "" ], [ "Nakai", "Yuichiro", "" ], [ "Suzuki", "Motoo", "" ] ]
We examine the possibility of building a natural non-supersymmetric model of spontaneous CP violation equipped with the Nelson-Barr (NB) mechanism to address the strong CP problem. Our approach is to utilize a doubly composite dynamics where the first confinement of the CFT occurs at the scale of spontaneous CP violation (SCPV) and the second confinement at the TeV scale. A holographic dual description of this 4D set-up via a warped extra dimension with three 3-branes provides an explicit realization of this idea.In this model, radiative corrections to the strong CP phase are well under control, and the coincidence of mass scales, which we generally encounter in NB models, is addressed. Our model also provides an explanation to the quark Yukawa hierarchies, and a solution to the gauge hierarchy problem just as in the usual Randall-Sundrum model with the Higgs being localized on the TeV brane.
2012.07925
Ananya Mukherjee
Monojit Ghosh, Srubabati Goswami, and Ananya Mukherjee
Implications of the Dark-LMA solution for neutrino mass matrices
18 pages, 5 figures. To appear in Nucl. Phys. B
null
10.1016/j.nuclphysb.2021.115460
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this work we have re-investigated two different kinds of texture zero ansatz of the low energy neutrino mass matrix in view of the Dark-Large-Mixing-Angle (DLMA) solution of the solar neutrino problem which can arise in the presence of non-standard interactions. In particular we revisit the cases of (i) one zero mass matrices when the lowest neutrino mass is zero and (ii) one zero texture with a vanishing minor. In our study we find that for most of the cases, the texture zero conditions which are allowed for the LMA solution, are also allowed for the DLMA solution. However, we found two textures belonging to the case of one zero texture with a vanishing minor where LMA solution does not give a viable solution whereas DLMA solution does. We analyze all the possible texture zero cases belonging to these two kinds of texture zero structures in detail and present correlations between different parameters. We also present the predictions for the effective neutrino mass governing neutrino-less double beta decay for the allowed textures.
[ { "created": "Mon, 14 Dec 2020 20:26:56 GMT", "version": "v1" }, { "created": "Mon, 7 Jun 2021 10:21:37 GMT", "version": "v2" } ]
2021-07-07
[ [ "Ghosh", "Monojit", "" ], [ "Goswami", "Srubabati", "" ], [ "Mukherjee", "Ananya", "" ] ]
In this work we have re-investigated two different kinds of texture zero ansatz of the low energy neutrino mass matrix in view of the Dark-Large-Mixing-Angle (DLMA) solution of the solar neutrino problem which can arise in the presence of non-standard interactions. In particular we revisit the cases of (i) one zero mass matrices when the lowest neutrino mass is zero and (ii) one zero texture with a vanishing minor. In our study we find that for most of the cases, the texture zero conditions which are allowed for the LMA solution, are also allowed for the DLMA solution. However, we found two textures belonging to the case of one zero texture with a vanishing minor where LMA solution does not give a viable solution whereas DLMA solution does. We analyze all the possible texture zero cases belonging to these two kinds of texture zero structures in detail and present correlations between different parameters. We also present the predictions for the effective neutrino mass governing neutrino-less double beta decay for the allowed textures.
hep-ph/9907316
John Vergados
J.D. Vergados (Institute for Theoretical Physics, University of Tuebingen, Tuebingen, Germany)
Neutrinoless Double Beta Decay in Gauge Theories
Latex, 24 pages, 1 postscript figure, uses iopconf.sty
Phys.Atom.Nucl.63:1137-1150,2000; Yad.Fiz.63N7:1213-1226,2000
10.1134/1.855759
null
hep-ph nucl-th
null
Neutrinoless double beta decay is a very important process both from the particle and nuclear physics point of view. Its observation will severely constrain the existing models and signal that the neutrinos are massive Majorana particles. From the elementary particle point of view it pops up in almost every model. In addition to the traditional mechanisms, like the neutrino mass, the admixture of right handed currents etc, it may occur due to the R-parity violating supersymmetric (SUSY) interactions. From the nuclear physics point of view it is challenging, because: 1) The relevant nuclei have complicated nuclear structure. 2) The energetically allowed transitions are exhaust a small part of all the strength. 3) One must cope with the short distance behavior of the transition operators, especially when the intermediate particles are heavy (eg in SUSY models). Thus novel effects, like the double beta decay of pions in flight between nucleons, have to be considered. 4) The intermediate momenta involved are about 100 MeV. Thus one has to take into account possible momentum dependent terms in the nucleon current. We find that, for the mass mechanism, such modifications of the nucleon current for light neutrinos reduce the nuclear matrix elements by about 25 per cent, almost regardless of the nuclear model. In the case of heavy neutrinos the effect is much larger and model dependent. Taking the above effects into account, the available nuclear matrix elements for the experimentally interesting nuclei A = 76, 82, 96, 100, 116, 128, 130, 136 and 150 and the experimental limits on the life times we have extracted new stringent limits on the average neutrino mass and on the R-parity violating coupling for various SUSY models.
[ { "created": "Mon, 12 Jul 1999 19:30:46 GMT", "version": "v1" } ]
2011-04-15
[ [ "Vergados", "J. D.", "", "Institute for Theoretical Physics, University of\n Tuebingen, Tuebingen, Germany" ] ]
Neutrinoless double beta decay is a very important process both from the particle and nuclear physics point of view. Its observation will severely constrain the existing models and signal that the neutrinos are massive Majorana particles. From the elementary particle point of view it pops up in almost every model. In addition to the traditional mechanisms, like the neutrino mass, the admixture of right handed currents etc, it may occur due to the R-parity violating supersymmetric (SUSY) interactions. From the nuclear physics point of view it is challenging, because: 1) The relevant nuclei have complicated nuclear structure. 2) The energetically allowed transitions are exhaust a small part of all the strength. 3) One must cope with the short distance behavior of the transition operators, especially when the intermediate particles are heavy (eg in SUSY models). Thus novel effects, like the double beta decay of pions in flight between nucleons, have to be considered. 4) The intermediate momenta involved are about 100 MeV. Thus one has to take into account possible momentum dependent terms in the nucleon current. We find that, for the mass mechanism, such modifications of the nucleon current for light neutrinos reduce the nuclear matrix elements by about 25 per cent, almost regardless of the nuclear model. In the case of heavy neutrinos the effect is much larger and model dependent. Taking the above effects into account, the available nuclear matrix elements for the experimentally interesting nuclei A = 76, 82, 96, 100, 116, 128, 130, 136 and 150 and the experimental limits on the life times we have extracted new stringent limits on the average neutrino mass and on the R-parity violating coupling for various SUSY models.
1410.6478
Stephane Munier
Stephane Munier
Lecture notes on "Quantum chromodynamics and statistical physics"
58 pages, 32 figures. Lectures given at the Huada school on QCD, Central China Normal University, Wuhan, China, June 2-13, 2014
Science China Physics, Mechanics & Astronomy Vol. 58 No. 8: 081001 (2015)
10.1007/s11433-015-5666-7
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The concepts and methods used for the study of disordered systems have proven useful in the analysis of the evolution equations of quantum chromodynamics in the high-energy regime: Indeed, parton branching in the semi-classical approximation relevant at high energies is a peculiar branching-diffusion process, and parton branching supplemented by saturation effects (such as gluon recombination) is a reaction-diffusion process. In these lectures, we first introduce the basic concepts in the context of simple toy models, we study the properties of the latter, and show how the results obtained for the simple models may be taken over to quantum chromodynamics.
[ { "created": "Thu, 23 Oct 2014 20:00:01 GMT", "version": "v1" } ]
2015-07-06
[ [ "Munier", "Stephane", "" ] ]
The concepts and methods used for the study of disordered systems have proven useful in the analysis of the evolution equations of quantum chromodynamics in the high-energy regime: Indeed, parton branching in the semi-classical approximation relevant at high energies is a peculiar branching-diffusion process, and parton branching supplemented by saturation effects (such as gluon recombination) is a reaction-diffusion process. In these lectures, we first introduce the basic concepts in the context of simple toy models, we study the properties of the latter, and show how the results obtained for the simple models may be taken over to quantum chromodynamics.
hep-ph/0504066
Utpal Sarkar
Bipin R. Desai, G. Rajasekaran and U. Sarkar
Large neutrino mixing angles for type-I see-saw mechanism in SO(10) GUT
8 pages
null
null
IMSc/2005/03/06, PRL-TH-05/02
hep-ph
null
We consider the neutrino mixing angles in an SO(10) GUT with the usual Higgs structure in which neutrino masses are explained by the type-I see-saw mechanism. The Dirac-neutrino Yukawa matrix then has a structure similar to that of the $u$-quark. We determine the light neutrino mass matrix through type-I see-saw mechanism using the experimentally consistent $u$-quark Yukawa matrix. We find that large neutrino mixing-angles emerge naturally in this model.
[ { "created": "Fri, 8 Apr 2005 11:28:11 GMT", "version": "v1" } ]
2007-05-23
[ [ "Desai", "Bipin R.", "" ], [ "Rajasekaran", "G.", "" ], [ "Sarkar", "U.", "" ] ]
We consider the neutrino mixing angles in an SO(10) GUT with the usual Higgs structure in which neutrino masses are explained by the type-I see-saw mechanism. The Dirac-neutrino Yukawa matrix then has a structure similar to that of the $u$-quark. We determine the light neutrino mass matrix through type-I see-saw mechanism using the experimentally consistent $u$-quark Yukawa matrix. We find that large neutrino mixing-angles emerge naturally in this model.
2202.08354
Fidele Twagirayezu
Fidele J. Twagirayezu
Effect of minimal length uncertainty on neutrino oscillation
10 pages
null
10.1515/zna-2022-0225
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
In this paper, we study the effect of the minimal length on neutrino oscillation in a static magnetic field. In the framework of the generalized uncertainty principle, we reformulate the Hamiltonian for a relativistic neutrino moving in a magnetic field oriented along the z-direction of Cartesian coordinates. Using the modified energy spectrum, we obtain the oscillation probability for different neutrino flavors. In addition, we obtain the energy differences for the neutrino-mass eigenstates. We find that the energy and energy difference depend on the minimal length parameter {\alpha}, and the energy difference becomes independent of {\alpha} when the magnetic field is not present. In addition, we find that the modified probability of oscillation differs from the usual probability of oscillation if a magnetic field is present. Using the current experimental result, we estimate the upper bound on the deformation parameter and the minimal length, and find that the upper bound on the minimal length scale is less than the electroweak scale. If the minimal length is at Planck scale, the minimal length formalism leads to the same result as a quantum theory of gravity with an $SU(2)_{L} \times U(1)$ effective invariant dimension-5 Lagrangian including neutrino and Higgs fields.
[ { "created": "Tue, 15 Feb 2022 08:17:38 GMT", "version": "v1" }, { "created": "Thu, 9 Mar 2023 17:54:01 GMT", "version": "v2" } ]
2023-05-31
[ [ "Twagirayezu", "Fidele J.", "" ] ]
In this paper, we study the effect of the minimal length on neutrino oscillation in a static magnetic field. In the framework of the generalized uncertainty principle, we reformulate the Hamiltonian for a relativistic neutrino moving in a magnetic field oriented along the z-direction of Cartesian coordinates. Using the modified energy spectrum, we obtain the oscillation probability for different neutrino flavors. In addition, we obtain the energy differences for the neutrino-mass eigenstates. We find that the energy and energy difference depend on the minimal length parameter {\alpha}, and the energy difference becomes independent of {\alpha} when the magnetic field is not present. In addition, we find that the modified probability of oscillation differs from the usual probability of oscillation if a magnetic field is present. Using the current experimental result, we estimate the upper bound on the deformation parameter and the minimal length, and find that the upper bound on the minimal length scale is less than the electroweak scale. If the minimal length is at Planck scale, the minimal length formalism leads to the same result as a quantum theory of gravity with an $SU(2)_{L} \times U(1)$ effective invariant dimension-5 Lagrangian including neutrino and Higgs fields.
0712.0095
Anibal Medina
Marcela Carena, Anibal D. Medina, Boris Panes, Nausheen R. Shah and Carlos E.M. Wagner
Collider Phenomenology of Gauge-Higgs Unification Scenarios in Warped Extra Dimensions
40 pages, 20 figures
Phys.Rev.D77:076003,2008
10.1103/PhysRevD.77.076003
ANL-HEP-PR-07-101, EFI-07-35, FERMILAB-PUB-07-630-T
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We compute the couplings of the zero modes and first excited states of gluons, $W$'s, $Z$ gauge bosons, as well as the Higgs, to the zero modes and first excited states of the third generation quarks, in an RS Gauge-Higgs unification scenario based on a bulk $SO(5)\times U(1)_X$ gauge symmetry, with gauge and fermion fields propagating in the bulk. Using the parameter space consistent with electroweak precision tests and radiative electroweak symmetry breaking, we study numerically the dependence of these couplings on the parameters of our model. Furthermore, after emphasizing the presence of light excited states of the top quark, which couple strongly to the Kaluza Klein gauge bosons, the associated collider phenomenology is analyzed. In particular, we concentrate on the possible detection of the first excited state of the top, $t^1$, which tends to have a higher mass than the ones accessible via regular QCD production processes. We stress that the detection of these particles is still possible due to an increase in the pair production of $t^1$ induced by the first excited state of the gluon, $G^1$.
[ { "created": "Sat, 1 Dec 2007 17:19:57 GMT", "version": "v1" }, { "created": "Wed, 9 Jul 2008 17:44:14 GMT", "version": "v2" } ]
2008-11-26
[ [ "Carena", "Marcela", "" ], [ "Medina", "Anibal D.", "" ], [ "Panes", "Boris", "" ], [ "Shah", "Nausheen R.", "" ], [ "Wagner", "Carlos E. M.", "" ] ]
We compute the couplings of the zero modes and first excited states of gluons, $W$'s, $Z$ gauge bosons, as well as the Higgs, to the zero modes and first excited states of the third generation quarks, in an RS Gauge-Higgs unification scenario based on a bulk $SO(5)\times U(1)_X$ gauge symmetry, with gauge and fermion fields propagating in the bulk. Using the parameter space consistent with electroweak precision tests and radiative electroweak symmetry breaking, we study numerically the dependence of these couplings on the parameters of our model. Furthermore, after emphasizing the presence of light excited states of the top quark, which couple strongly to the Kaluza Klein gauge bosons, the associated collider phenomenology is analyzed. In particular, we concentrate on the possible detection of the first excited state of the top, $t^1$, which tends to have a higher mass than the ones accessible via regular QCD production processes. We stress that the detection of these particles is still possible due to an increase in the pair production of $t^1$ induced by the first excited state of the gluon, $G^1$.
hep-ph/9605378
Tomohiro Matsuda
Tomohiro Matsuda
Alternative Approach to Gaugino Condensation
References and review are slightly changed, 12 pages, latex
Phys.Rev. D54 (1996) 7650-7655
10.1103/PhysRevD.54.7650
UT-746
hep-ph hep-th
null
We examine the mechanism of gaugino condensation in supersymmetric theories within a Nambu-Jona-Lasinio type approach. We investigate the effective Lagrangian description of higher energy theories that include some moduli fields in the gauge coupling constant. First we consider supersymmetric QCD with and without a mass term. We can find a phase transition in massless theory, but when we add a mass term, such a phase transition disappears. We also examine a model with a dilaton dependent coupling constant and find that it is very similar to supersymmetric QCD. Application of our method to supergravity is also examined.
[ { "created": "Thu, 23 May 1996 08:04:04 GMT", "version": "v1" }, { "created": "Wed, 14 Aug 1996 06:51:48 GMT", "version": "v2" } ]
2009-10-28
[ [ "Matsuda", "Tomohiro", "" ] ]
We examine the mechanism of gaugino condensation in supersymmetric theories within a Nambu-Jona-Lasinio type approach. We investigate the effective Lagrangian description of higher energy theories that include some moduli fields in the gauge coupling constant. First we consider supersymmetric QCD with and without a mass term. We can find a phase transition in massless theory, but when we add a mass term, such a phase transition disappears. We also examine a model with a dilaton dependent coupling constant and find that it is very similar to supersymmetric QCD. Application of our method to supergravity is also examined.
1501.04964
Peter Arnold
Peter Arnold and Shahin Iqbal
The LPM effect in sequential bremsstrahlung
85 pages, 30 figures [only change from v5: fixed trivial typo of a missing bar in eq. (2.20a). The authors are obsessive.]
null
10.1007/JHEP04(2015)070
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The splitting processes of bremsstrahlung and pair production in a medium are coherent over large distances in the very high energy limit, which leads to a suppression known as the Landau-Pomeranchuk-Migdal (LPM) effect. We analyze the case when the coherence lengths of two consecutive splitting processes overlap, which is important for understanding corrections to standard treatments of the LPM effect in QCD. Previous authors have analyzed this problem in the case of overlapping double bremsstrahlung where at least one of the bremsstrahlung gluons is soft. Here we show how to generalize to include the case where both splittings are hard. A number of techniques must be developed, and so in this paper we simplify by (i) restricting attention to a subset of the interference effects, which we call the "crossed" diagrams, and (ii) working in the large-$N_c$ limit. We first develop some general formulas that could in principle be implemented numerically (with substantial difficulty). To make more analytic progress, we then focus on the case of a thick, homogeneous medium and make the multiple scattering approximation (also known as the $\hat q$ or harmonic approximation) appropriate at high energy. We show that the differential rate $d\Gamma/dx\,dy$ for overlapping double bremsstrahlung of gluons with momentum fractions $x$ and $y$ can then be reduced to the calculation of a 1-dimensional integral, which we perform numerically. [Though this paper is unfortunately long, our introduction is enough for getting the gist of the method.]
[ { "created": "Tue, 20 Jan 2015 21:00:10 GMT", "version": "v1" }, { "created": "Fri, 27 Feb 2015 20:05:15 GMT", "version": "v2" }, { "created": "Mon, 13 Apr 2015 22:11:08 GMT", "version": "v3" }, { "created": "Tue, 9 Jun 2015 20:05:07 GMT", "version": "v4" }, { "cr...
2016-10-20
[ [ "Arnold", "Peter", "" ], [ "Iqbal", "Shahin", "" ] ]
The splitting processes of bremsstrahlung and pair production in a medium are coherent over large distances in the very high energy limit, which leads to a suppression known as the Landau-Pomeranchuk-Migdal (LPM) effect. We analyze the case when the coherence lengths of two consecutive splitting processes overlap, which is important for understanding corrections to standard treatments of the LPM effect in QCD. Previous authors have analyzed this problem in the case of overlapping double bremsstrahlung where at least one of the bremsstrahlung gluons is soft. Here we show how to generalize to include the case where both splittings are hard. A number of techniques must be developed, and so in this paper we simplify by (i) restricting attention to a subset of the interference effects, which we call the "crossed" diagrams, and (ii) working in the large-$N_c$ limit. We first develop some general formulas that could in principle be implemented numerically (with substantial difficulty). To make more analytic progress, we then focus on the case of a thick, homogeneous medium and make the multiple scattering approximation (also known as the $\hat q$ or harmonic approximation) appropriate at high energy. We show that the differential rate $d\Gamma/dx\,dy$ for overlapping double bremsstrahlung of gluons with momentum fractions $x$ and $y$ can then be reduced to the calculation of a 1-dimensional integral, which we perform numerically. [Though this paper is unfortunately long, our introduction is enough for getting the gist of the method.]
2402.16344
Xin-Shuai Yan
Xin-Shuai Yan, Liang-Hui Zhang, Qin Chang, and Ya-Dong Yang
Probing new physics with polarization components of the tau lepton in quasielastic $e^- p \to \Lambda_c \tau^-$ scattering process
20 pages, 4 figures, 5 tables
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Kinematics restrict the ability of rare charm decays to explore the charged Lepton Flavor Violation processes mediated by the quark-level $c\to u \ell \tau$ transition. To fill the gap, we propose exploring new physics (NP) through the quasielastic scattering process $e^-p\to \tau^-\Lambda_c$ and the polarization of the $\tau$ lepton. As analyzing modes for the $\tau$ polarization, we consider the decays $\tau^-\to \pi^-\nu_{\tau}$, $\tau^-\to \rho^-\nu_{\tau}$, and $\tau^- \to \ell^-\bar{\nu}_{\ell}\nu_{\tau}$, and show that the $\tau$ polarization components can be extracted from analyzing the kinematics of the $\tau$ visible decay products. In the framework of a general low-energy effective Lagrangian, we then perform a detailed analysis of the polarization components in various aspects and scrutinize possible NP signals. With one upcoming experimental setup, we finally demonstrate promising event rate can be expected for the cascade process and, even in the worst-case scenario -- no signals is observed at all -- it can still provide a competitive potential for constraining the NP, compared with those from the high-$p_T$ dilepton invariant mass tails at high-energy colliders.
[ { "created": "Mon, 26 Feb 2024 06:58:47 GMT", "version": "v1" }, { "created": "Sun, 7 Apr 2024 00:48:05 GMT", "version": "v2" } ]
2024-04-09
[ [ "Yan", "Xin-Shuai", "" ], [ "Zhang", "Liang-Hui", "" ], [ "Chang", "Qin", "" ], [ "Yang", "Ya-Dong", "" ] ]
Kinematics restrict the ability of rare charm decays to explore the charged Lepton Flavor Violation processes mediated by the quark-level $c\to u \ell \tau$ transition. To fill the gap, we propose exploring new physics (NP) through the quasielastic scattering process $e^-p\to \tau^-\Lambda_c$ and the polarization of the $\tau$ lepton. As analyzing modes for the $\tau$ polarization, we consider the decays $\tau^-\to \pi^-\nu_{\tau}$, $\tau^-\to \rho^-\nu_{\tau}$, and $\tau^- \to \ell^-\bar{\nu}_{\ell}\nu_{\tau}$, and show that the $\tau$ polarization components can be extracted from analyzing the kinematics of the $\tau$ visible decay products. In the framework of a general low-energy effective Lagrangian, we then perform a detailed analysis of the polarization components in various aspects and scrutinize possible NP signals. With one upcoming experimental setup, we finally demonstrate promising event rate can be expected for the cascade process and, even in the worst-case scenario -- no signals is observed at all -- it can still provide a competitive potential for constraining the NP, compared with those from the high-$p_T$ dilepton invariant mass tails at high-energy colliders.
1106.5499
Andreas Crivellin
Andreas Crivellin and Lorenzo Mercolli
B -> X_d gamma and constraints on new physics
5 pages, 3 figures, experimental value for b->d+gamma corrected, version accepted for publication in PRD
null
10.1103/PhysRevD.84.114005
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We combine recent progress in measuring the branching ratio of the decay B->X_d gamma$ with the discovery that hadronic uncertainties in the CP-averaged branching ratio drop out to a large extent. Implications of these improvements on the size of possible new physics effects are investigated. We find the updated SM prediction for the CP-averaged branching ratio to be Br[B->X_d gamma]^SM_E_gamma>1.6 GeV = 1.54^+0.26-0.31*10^-5, which should be compared with the experimental value of Br[B->X_d gamma]^exp_E_gamma>1.6GeV = (1.41+-0.57) 10^-5. After performing a model independent analysis, we consider different new physics models: the MSSM with generic sources of flavor violation, the two Higgs doublet model of type III and a model with right-handed charged currents. It is found that the constraints on the SUSY parameters delta^d_13 have improved and that the absolute value of the right-handed quark mixing matrix element |V^R_td| must be smaller than 1.5*10^-4.
[ { "created": "Mon, 27 Jun 2011 20:00:03 GMT", "version": "v1" }, { "created": "Wed, 29 Jun 2011 10:43:56 GMT", "version": "v2" }, { "created": "Fri, 12 Aug 2011 00:30:38 GMT", "version": "v3" }, { "created": "Thu, 10 Nov 2011 17:44:48 GMT", "version": "v4" } ]
2015-03-19
[ [ "Crivellin", "Andreas", "" ], [ "Mercolli", "Lorenzo", "" ] ]
We combine recent progress in measuring the branching ratio of the decay B->X_d gamma$ with the discovery that hadronic uncertainties in the CP-averaged branching ratio drop out to a large extent. Implications of these improvements on the size of possible new physics effects are investigated. We find the updated SM prediction for the CP-averaged branching ratio to be Br[B->X_d gamma]^SM_E_gamma>1.6 GeV = 1.54^+0.26-0.31*10^-5, which should be compared with the experimental value of Br[B->X_d gamma]^exp_E_gamma>1.6GeV = (1.41+-0.57) 10^-5. After performing a model independent analysis, we consider different new physics models: the MSSM with generic sources of flavor violation, the two Higgs doublet model of type III and a model with right-handed charged currents. It is found that the constraints on the SUSY parameters delta^d_13 have improved and that the absolute value of the right-handed quark mixing matrix element |V^R_td| must be smaller than 1.5*10^-4.
0912.4221
Masahiro Ibe
Masahiro Ibe, Tsutomu T. Yanagida
Neutralino Dark Matter in Gauge Mediation in Light of CDMS-II
4 pages; an appendix added; several references added
Phys.Rev.D81:035017,2010
10.1103/PhysRevD.81.035017
IPMU09-0161
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A recent observation of the two candidate events of the dark matter recoiling at CDMS-II is suggestive of dark matter with a mass not far above 100GeV. We propose a model of gauge mediated supersymmetry breaking where the lightest neutralino is identified as dark matter which may provide the observed signals.
[ { "created": "Mon, 21 Dec 2009 17:52:43 GMT", "version": "v1" }, { "created": "Thu, 24 Dec 2009 19:38:37 GMT", "version": "v2" } ]
2010-04-06
[ [ "Ibe", "Masahiro", "" ], [ "Yanagida", "Tsutomu T.", "" ] ]
A recent observation of the two candidate events of the dark matter recoiling at CDMS-II is suggestive of dark matter with a mass not far above 100GeV. We propose a model of gauge mediated supersymmetry breaking where the lightest neutralino is identified as dark matter which may provide the observed signals.
1107.4683
Fred Jegerlehner
Fred Jegerlehner
Electroweak effective couplings for future precision experiments
10 pages, 3 figures
null
10.1393/ncc/i2011-11011-0
HU-EP-11/33, DESY 11-117
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The leading hadronic effects in electroweak theory derive from vacuum polarization which are non-perturbative hadronic contributions to the running of the gauge couplings, the electromagnetic alpha_{em}(s) and the SU(2)_L coupling alpha_2(s). I will report on my recent package "alphaQED", which besides the effective fine structure constant alpha_{em}(s) also allows for a fairly precise calculation of the SU(2)_L gauge coupling alpha_2(s). I will briefly review the role, future requirements and possibilities. Applied together with the "Rhad" package by Harlander and Steinhauser, the package allows to calculate all SM running couplings as well as running sin^2 Theta versions with state-of-the-art accuracy.
[ { "created": "Sat, 23 Jul 2011 11:35:06 GMT", "version": "v1" } ]
2022-03-02
[ [ "Jegerlehner", "Fred", "" ] ]
The leading hadronic effects in electroweak theory derive from vacuum polarization which are non-perturbative hadronic contributions to the running of the gauge couplings, the electromagnetic alpha_{em}(s) and the SU(2)_L coupling alpha_2(s). I will report on my recent package "alphaQED", which besides the effective fine structure constant alpha_{em}(s) also allows for a fairly precise calculation of the SU(2)_L gauge coupling alpha_2(s). I will briefly review the role, future requirements and possibilities. Applied together with the "Rhad" package by Harlander and Steinhauser, the package allows to calculate all SM running couplings as well as running sin^2 Theta versions with state-of-the-art accuracy.
hep-ph/0702063
Hiroto Nakajima
H. Nakajima and Y. Shinbara
Solutions to large B and L breaking in the Randall-Sundrum model
12 pages, No figures, Added references
Phys.Lett.B648:294-300,2007
10.1016/j.physletb.2007.03.033
UT-07-06
hep-ph
null
The stability of proton and neutrino masses are discussed in the Randall-Sundrum model. We show that relevant operators should be suppressed, if the hierarchical Yukawa matrices are explained only by configurations of wavefunctions for fermions and the Higgs field along the extra dimension. We assume a $Z_N$ discrete gauge symmetry to suppress those operators. In the Dirac neutrino case, there is an infinite number of symmetries which may forbid the dangerous operators. In the Majorana neutrino case, the discrete gauge symmetries should originate from $U(1)_X$ gauge symmetries which are broken on the Planck brane. We also comment on the $n-\bar{n}$ oscillation as a phenomenon which can distinguish those discrete gauge symmetries.
[ { "created": "Tue, 6 Feb 2007 08:53:37 GMT", "version": "v1" }, { "created": "Fri, 25 May 2007 07:06:04 GMT", "version": "v2" } ]
2008-11-26
[ [ "Nakajima", "H.", "" ], [ "Shinbara", "Y.", "" ] ]
The stability of proton and neutrino masses are discussed in the Randall-Sundrum model. We show that relevant operators should be suppressed, if the hierarchical Yukawa matrices are explained only by configurations of wavefunctions for fermions and the Higgs field along the extra dimension. We assume a $Z_N$ discrete gauge symmetry to suppress those operators. In the Dirac neutrino case, there is an infinite number of symmetries which may forbid the dangerous operators. In the Majorana neutrino case, the discrete gauge symmetries should originate from $U(1)_X$ gauge symmetries which are broken on the Planck brane. We also comment on the $n-\bar{n}$ oscillation as a phenomenon which can distinguish those discrete gauge symmetries.
hep-ph/0103189
Qsyan
Qi-Shu Yan
Radiative electroweak symmetry breaking in the extra dimensions scenarios
References added and the figure redrawn
null
null
null
hep-ph
null
We study the radiative spontaneous electroweak symmetry breaking in the extra dimensions scenarios of the standard model extension proposed by Antoniadis {\it et al}, Dienes {\it et al.} and Pomarol {\it et al.}. In the framework of multi-scale effective theory when viewing from the ultraviolet cutoff scale down to the low energy scale, we find that the effects of Kaluza-Klein excitations of bosons can change the sign of the Higgs mass term of the standard model from positive to negative and therefore trigger the electroweak symmetry breaking at 1.6 (2) TeV or so when the compactification scale is assumed to be 0.8 (1.5) TeV or so. New particle contents beyond the SM or supersymmetry are not necessary for this mechanism. We conclude that in the extra dimension scenarios, the radiative correction can naturally induce the desired electroweak symmetry breaking.
[ { "created": "Sun, 18 Mar 2001 04:41:51 GMT", "version": "v1" }, { "created": "Tue, 20 Mar 2001 02:24:13 GMT", "version": "v2" }, { "created": "Thu, 22 Mar 2001 12:57:29 GMT", "version": "v3" } ]
2016-09-06
[ [ "Yan", "Qi-Shu", "" ] ]
We study the radiative spontaneous electroweak symmetry breaking in the extra dimensions scenarios of the standard model extension proposed by Antoniadis {\it et al}, Dienes {\it et al.} and Pomarol {\it et al.}. In the framework of multi-scale effective theory when viewing from the ultraviolet cutoff scale down to the low energy scale, we find that the effects of Kaluza-Klein excitations of bosons can change the sign of the Higgs mass term of the standard model from positive to negative and therefore trigger the electroweak symmetry breaking at 1.6 (2) TeV or so when the compactification scale is assumed to be 0.8 (1.5) TeV or so. New particle contents beyond the SM or supersymmetry are not necessary for this mechanism. We conclude that in the extra dimension scenarios, the radiative correction can naturally induce the desired electroweak symmetry breaking.
hep-ph/0405224
Hirotaka Sugawara
Hirotaka Sugawara
M-Theory Phenomenology and See-Saw Mechanisms
19 pages, 16 figures, Talk given at Neutrino Mass and See-Saw Mechanism, Fujihara Seminar
null
10.1016/j.nuclphysbps.2004.10.074
KEK-TH-958
hep-ph
null
A version of M-theory phenomenology is proposed in which the symmetry is based on the group $SO(10) \times SO(10) \times SO(10) \times U(1) \times U(1)$. Each SO(10) group acts on a single generation. The $U(1) \times U(1)$ is regarded as the hidden sector symmetry group. The supersymmetry is broken in the hidden sector by the Fayet-Iliopoulos $D$-term for each group. The $D$-term is needed also to circumvent the powerful non-renormalization theorem since the $SO(10) \times SO(10) \times SO(10)$ is broken down to the usual SO(10) by the pair condensation of certain messenger sector multiplets. The exchange of U(1) gauge bosons gives an attractive force for the pair to be created and condensed. The off-diagonal mass matrix elements among the generations in these messenger sector multiplets are the source of the flavor dynamics including the CP violation. The pair condensation of another multiplet in the messenger sector leads to the doublet-triplet splitting. The SO(10) decuplet Higgs couples only to one of the generations. The other couplings should, therefore, be calculated as higher order corrections. We present our preliminary results on the calculation of the mass matrices and the mixing angles for leptons and quarks in this model.
[ { "created": "Sun, 23 May 2004 19:39:32 GMT", "version": "v1" } ]
2009-11-10
[ [ "Sugawara", "Hirotaka", "" ] ]
A version of M-theory phenomenology is proposed in which the symmetry is based on the group $SO(10) \times SO(10) \times SO(10) \times U(1) \times U(1)$. Each SO(10) group acts on a single generation. The $U(1) \times U(1)$ is regarded as the hidden sector symmetry group. The supersymmetry is broken in the hidden sector by the Fayet-Iliopoulos $D$-term for each group. The $D$-term is needed also to circumvent the powerful non-renormalization theorem since the $SO(10) \times SO(10) \times SO(10)$ is broken down to the usual SO(10) by the pair condensation of certain messenger sector multiplets. The exchange of U(1) gauge bosons gives an attractive force for the pair to be created and condensed. The off-diagonal mass matrix elements among the generations in these messenger sector multiplets are the source of the flavor dynamics including the CP violation. The pair condensation of another multiplet in the messenger sector leads to the doublet-triplet splitting. The SO(10) decuplet Higgs couples only to one of the generations. The other couplings should, therefore, be calculated as higher order corrections. We present our preliminary results on the calculation of the mass matrices and the mixing angles for leptons and quarks in this model.
hep-ph/9705340
Will Loinaz
D. Boyanovsky, Will Loinaz, R.S. Willey (U. of Pittsburgh)
Gauge Invariant Higgs mass bounds from the Physical Effective Potential
23 pages, 2 figures, REVTEX
Phys.Rev. D57 (1998) 100-111
10.1103/PhysRevD.57.100
null
hep-ph
null
We study a simplified version of the Standard Electroweak Model and introduce the concept of the physical gauge invariant effective potential in terms of matrix elements of the Hamiltonian in physical states. This procedure allows an unambiguous identification of the symmetry breaking order parameter and the resulting effective potential as the energy in a constrained state. We explicitly compute the physical effective potential at one loop order and improve it using the RG. This construction allows us to extract a reliable, gauge invariant bound on the Higgs mass by unambiguously obtaining the scale at which new physics should emerge to preclude vacuum instability. Comparison is made with popular gauge fixing procedures and an ``error'' estimate is provided between the Landau gauge fixed and the gauge invariant results.
[ { "created": "Fri, 16 May 1997 16:02:37 GMT", "version": "v1" } ]
2009-10-30
[ [ "Boyanovsky", "D.", "", "U. of Pittsburgh" ], [ "Loinaz", "Will", "", "U. of Pittsburgh" ], [ "Willey", "R. S.", "", "U. of Pittsburgh" ] ]
We study a simplified version of the Standard Electroweak Model and introduce the concept of the physical gauge invariant effective potential in terms of matrix elements of the Hamiltonian in physical states. This procedure allows an unambiguous identification of the symmetry breaking order parameter and the resulting effective potential as the energy in a constrained state. We explicitly compute the physical effective potential at one loop order and improve it using the RG. This construction allows us to extract a reliable, gauge invariant bound on the Higgs mass by unambiguously obtaining the scale at which new physics should emerge to preclude vacuum instability. Comparison is made with popular gauge fixing procedures and an ``error'' estimate is provided between the Landau gauge fixed and the gauge invariant results.
hep-ph/9504223
Dirk Graudenz
DIRK GRAUDENZ (CERN)
THE PHYSICS OF THE STANDARD MODEL HIGGS BOSON AT THE LHC
6 pages (LaTeX); figures are included via epsfig; the corresponding postscript files are uuencoded
null
null
CERN-TH/95-77
hep-ph
null
Some topics related to Standard Model Higgs boson physics at the Large Hadron Collider are reviewed. Emphasis is put on an overview of QCD corrections to Higgs boson decay and production processes. (Invited talk presented at the XXXth Rencontres de Moriond, Les Arcs 1800, March 19-26, 1995; to appear in the proceedings of the conference.)
[ { "created": "Wed, 5 Apr 1995 07:38:43 GMT", "version": "v1" } ]
2007-05-23
[ [ "GRAUDENZ", "DIRK", "", "CERN" ] ]
Some topics related to Standard Model Higgs boson physics at the Large Hadron Collider are reviewed. Emphasis is put on an overview of QCD corrections to Higgs boson decay and production processes. (Invited talk presented at the XXXth Rencontres de Moriond, Les Arcs 1800, March 19-26, 1995; to appear in the proceedings of the conference.)
2308.05210
Emre Gurkanli
A. Guti\'errez-Rodr\'iguez, E. Gurkanli, M. K\"oksal, V. Ari, M. A. Hern\'andez-Ru\'iz
Expected sensitivity on the anomalous quartic neutral gauge couplings in $\gamma\gamma$ collisions at the CLIC
21 pages, 6 figures
null
10.1140/epjp/s13360-023-04779-4
null
hep-ph
http://creativecommons.org/licenses/by/4.0/
The presence of multi-boson self-interactions is implied by the non-Abelian gauge structure of the Standard Model (SM). Precise measurements of these interactions allow not only testing the nature of the SM but also new physics contribution arising from the beyond SM. The investigation of these interactions can be approached in a model-independent manner using an effective theory approach, which forms the main motivation of this study. In this paper, we examine the anomalous neutral quartic gauge couplings through the process $\gamma \gamma \rightarrow Z Z$ at the Compact Linear Collider (CLIC) with the center-of-mass energy of $\sqrt{s}=3$ TeV, integrated luminosities of ${\cal L}=5$ $\rm ab^{-1}$. The anomalous neutral quartic gauge couplings is implemented into FeynRules to generate a UFO module inserted into Madgraph to generate both background and signal events. These events are then passed through Pythia 8 for parton showering and Delphes to include realistic detector effects. We obtain that the sensitivities on the anomalous quartic neutral gauge couplings with $95\%$ Confidence Level are given as: $f_{T0}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$, $f_{T1}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$,$f_{T2}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$,$f_{T0}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$, $f_{T5}/\Lambda^{4}=[-4.08; 4.08]\times 10^{-4}$ ${\rm TeV^{-4}}$ and $f_{T8}/\Lambda^{4}=[-1.10; 1.10]\times10^{-4}$ ${\rm TeV^{-4}}$. Our results on the anomalous quartic neutral gauge couplings are set more stringent sensitivity with respect to the recent experimental limits.
[ { "created": "Wed, 9 Aug 2023 20:22:59 GMT", "version": "v1" }, { "created": "Tue, 19 Dec 2023 11:28:08 GMT", "version": "v2" } ]
2023-12-20
[ [ "Gutiérrez-Rodríguez", "A.", "" ], [ "Gurkanli", "E.", "" ], [ "Köksal", "M.", "" ], [ "Ari", "V.", "" ], [ "Hernández-Ruíz", "M. A.", "" ] ]
The presence of multi-boson self-interactions is implied by the non-Abelian gauge structure of the Standard Model (SM). Precise measurements of these interactions allow not only testing the nature of the SM but also new physics contribution arising from the beyond SM. The investigation of these interactions can be approached in a model-independent manner using an effective theory approach, which forms the main motivation of this study. In this paper, we examine the anomalous neutral quartic gauge couplings through the process $\gamma \gamma \rightarrow Z Z$ at the Compact Linear Collider (CLIC) with the center-of-mass energy of $\sqrt{s}=3$ TeV, integrated luminosities of ${\cal L}=5$ $\rm ab^{-1}$. The anomalous neutral quartic gauge couplings is implemented into FeynRules to generate a UFO module inserted into Madgraph to generate both background and signal events. These events are then passed through Pythia 8 for parton showering and Delphes to include realistic detector effects. We obtain that the sensitivities on the anomalous quartic neutral gauge couplings with $95\%$ Confidence Level are given as: $f_{T0}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$, $f_{T1}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$,$f_{T2}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$,$f_{T0}/\Lambda^{4}=[-1.06; 1.08]\times 10^{-3}$ ${\rm TeV^{-4}}$, $f_{T5}/\Lambda^{4}=[-4.08; 4.08]\times 10^{-4}$ ${\rm TeV^{-4}}$ and $f_{T8}/\Lambda^{4}=[-1.10; 1.10]\times10^{-4}$ ${\rm TeV^{-4}}$. Our results on the anomalous quartic neutral gauge couplings are set more stringent sensitivity with respect to the recent experimental limits.
2106.15228
Keisho Hidaka
H. Eberl (1), K. Hidaka (2), E. Ginina (1, 3) and A. Ishikawa (4, 5,6) ((1) HEPHY, Vienna, (2) Tokyo Gakugei U., (3) VRV, Vienna, (4) KEK, Tsukuba, (5) SOKENDAI, Hayama, (6) ICEPP, Tokyo)
Imprint of SUSY in radiative B-meson decays
34 pages, 13 figures, a few comments added, final result unchanged
Phys. Rev. D104 (2021) 075025
10.1103/PhysRevD.104.075025
HEPHY-PUB 1024/21, KEK Preprint 2021-7
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We study supersymmetric (SUSY) effects on $C_7(\mu_b)$ and $C'_7(\mu_b)$ which are the Wilson coefficients (WCs) for $b \to s \gamma$ at b-quark mass scale $\mu_b$ and are closely related to radiative $B$-meson decays. The SUSY-loop contributions to $C_7(\mu_b)$ and $C'_7(\mu_b)$ are calculated at leading order (LO) in the Minimal Supersymmetric Standard Model (MSSM) with general quark-flavour violation (QFV). For the first time we perform a systematic MSSM parameter scan for the WCs $C_7(\mu_b)$ and $C'_7(\mu_b)$ respecting all the relevant constraints, i.e. the theoretical constraints from vacuum stability conditions and the experimental constraints, such as those from $K$- and $B$-meson data and electroweak precision data, as well as recent limits on SUSY particle masses and the 125 GeV Higgs boson data from LHC experiments. From the parameter scan we find the following: (1) The MSSM contribution to Re($C_7(\mu_b)$) can be as large as $\sim \pm 0.05$, which could correspond to about 3$\sigma$ significance of New Physics (NP) signal in the future LHCb and Belle II experiments. (2) The MSSM contribution to Re($C'_7(\mu_b)$) can be as large as $\sim -0.08$, which could correspond to about 4$\sigma$ significance of NP signal in the future LHCb and Belle II experiments. (3) These large MSSM contributions to the WCs are mainly due to (i) large scharm-stop mixing and large scharm/stop involved trilinear couplings, (ii) large sstrange-sbottom mixing and large sstrange-sbottom involved trilinear couplings and (iii) large bottom Yukawa coupling $Y_b$ for large $\tan\beta$ and large top Yukawa coupling $Y_t$. In case such large NP contributions to the WCs are really observed in the future experiments at Belle II and LHCb Upgrade, this could be the imprint of QFV SUSY (the MSSM with general QFV).
[ { "created": "Tue, 29 Jun 2021 10:25:59 GMT", "version": "v1" }, { "created": "Thu, 4 Nov 2021 15:32:24 GMT", "version": "v2" } ]
2021-11-05
[ [ "Eberl", "H.", "" ], [ "Hidaka", "K.", "" ], [ "Ginina", "E.", "" ], [ "Ishikawa", "A.", "" ] ]
We study supersymmetric (SUSY) effects on $C_7(\mu_b)$ and $C'_7(\mu_b)$ which are the Wilson coefficients (WCs) for $b \to s \gamma$ at b-quark mass scale $\mu_b$ and are closely related to radiative $B$-meson decays. The SUSY-loop contributions to $C_7(\mu_b)$ and $C'_7(\mu_b)$ are calculated at leading order (LO) in the Minimal Supersymmetric Standard Model (MSSM) with general quark-flavour violation (QFV). For the first time we perform a systematic MSSM parameter scan for the WCs $C_7(\mu_b)$ and $C'_7(\mu_b)$ respecting all the relevant constraints, i.e. the theoretical constraints from vacuum stability conditions and the experimental constraints, such as those from $K$- and $B$-meson data and electroweak precision data, as well as recent limits on SUSY particle masses and the 125 GeV Higgs boson data from LHC experiments. From the parameter scan we find the following: (1) The MSSM contribution to Re($C_7(\mu_b)$) can be as large as $\sim \pm 0.05$, which could correspond to about 3$\sigma$ significance of New Physics (NP) signal in the future LHCb and Belle II experiments. (2) The MSSM contribution to Re($C'_7(\mu_b)$) can be as large as $\sim -0.08$, which could correspond to about 4$\sigma$ significance of NP signal in the future LHCb and Belle II experiments. (3) These large MSSM contributions to the WCs are mainly due to (i) large scharm-stop mixing and large scharm/stop involved trilinear couplings, (ii) large sstrange-sbottom mixing and large sstrange-sbottom involved trilinear couplings and (iii) large bottom Yukawa coupling $Y_b$ for large $\tan\beta$ and large top Yukawa coupling $Y_t$. In case such large NP contributions to the WCs are really observed in the future experiments at Belle II and LHCb Upgrade, this could be the imprint of QFV SUSY (the MSSM with general QFV).
hep-ph/9409205
Ed Stoeffhaas
D. Zeppenfeld
Gluon Radiation Patterns in Pomeron Exchange Events
Talk given at the XXVII International Conference on High Energy Physics, Glasgow, Scotland, July 21--27, 1994. Latex file, uses ichep.sty, appended after "\end{document}". Three uufiled postscript figures included. Hardcopies available upon request. MAD/PH/846
null
null
null
hep-ph
null
Color singlet two gluon exchange provides a perturbative model for the pomeron. This mechanism is thought to explain the production of rapidity gaps in hard dijet events at the Tevatron. It is shown that in $qQ$ scattering via two gluon color singlet exchange the emission of soft gluons follows closely the pattern found for $t$-channel photon exchange. Gluon emission is strongly suppressed between the two quark jets. After hadronization this leads to a depressed level of hadronic activity between the jets and thus allows the formation of rapidity gaps.
[ { "created": "Thu, 1 Sep 1994 16:26:30 GMT", "version": "v1" } ]
2009-09-25
[ [ "Zeppenfeld", "D.", "" ] ]
Color singlet two gluon exchange provides a perturbative model for the pomeron. This mechanism is thought to explain the production of rapidity gaps in hard dijet events at the Tevatron. It is shown that in $qQ$ scattering via two gluon color singlet exchange the emission of soft gluons follows closely the pattern found for $t$-channel photon exchange. Gluon emission is strongly suppressed between the two quark jets. After hadronization this leads to a depressed level of hadronic activity between the jets and thus allows the formation of rapidity gaps.
2309.00547
Andre Hoang
Bahman Dehnadi, Andr\'e H. Hoang, Oliver L. Jin, and Vicent Mateu
Top Quark Mass Calibration for Monte Carlo Event Generators -- An Update
70 pages, 15 figures; minor improvements, results unchanged, version published in JHEP
null
null
UWThPh-2023-16, DESY-23-127
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
We generalize and update our former top quark mass calibration framework for Monte Carlo (MC) event generators based on the $e^+e^-$ hadron-level 2-jettiness $\tau_2$ distribution in the resonance region for boosted $t\bar t$ production, that was used to relate the PYTHIA 8.205 top mass parameter $m_t^{\rm MC}$ to the MSR mass $m_t^{\rm MSR}(R)$ and the pole mass $m_t^{\rm pole}$. The current most precise direct top mass measurements specifically determine $m_t^{\rm MC}$. The updated framework includes the addition of the shape variables sum of jet masses $\tau_s$ and modified jet mass $\tau_m$, and the treatment of two more gap subtraction schemes to remove the ${\cal O}(\Lambda_{\rm QCD})$ renormalon related to large-angle soft radiation. These generalizations entail implementing a more versatile shape-function fit procedure and accounting for a certain type of $(m_t/Q)^2$ power corrections to achieve gap-scheme and observable independent results. The theoretical description employs boosted heavy-quark effective theory (bHQET) at next-to-next-to-logarithmic order (N$^2$LL), matched to soft-collinear effective theory (SCET) at N$^2$LL and full QCD at next-to-leading order (NLO), and includes the dominant top width effects. Furthermore, the software framework has been modernized to use standard file and event record formats. We update the top mass calibration results by applying the new framework to PYTHIA 8.205, HERWIG 7.2 and SHERPA 2.2.11. Even though the hadron-level resonance positions produced by the three generators differ significantly for the same top mass parameter $m_t^{\rm MC}$ value, the calibration shows that these differences arise from the hadronization modeling. Indeed, we find that $m_t^{\rm MC}$ agrees with $m_t^{\rm MSR}(1\,\mbox{GeV})$ within $200$ MeV for the three generators and differs from the pole mass by $350$ to $600$ MeV.
[ { "created": "Fri, 1 Sep 2023 15:56:09 GMT", "version": "v1" }, { "created": "Sat, 9 Dec 2023 18:32:48 GMT", "version": "v2" } ]
2023-12-12
[ [ "Dehnadi", "Bahman", "" ], [ "Hoang", "André H.", "" ], [ "Jin", "Oliver L.", "" ], [ "Mateu", "Vicent", "" ] ]
We generalize and update our former top quark mass calibration framework for Monte Carlo (MC) event generators based on the $e^+e^-$ hadron-level 2-jettiness $\tau_2$ distribution in the resonance region for boosted $t\bar t$ production, that was used to relate the PYTHIA 8.205 top mass parameter $m_t^{\rm MC}$ to the MSR mass $m_t^{\rm MSR}(R)$ and the pole mass $m_t^{\rm pole}$. The current most precise direct top mass measurements specifically determine $m_t^{\rm MC}$. The updated framework includes the addition of the shape variables sum of jet masses $\tau_s$ and modified jet mass $\tau_m$, and the treatment of two more gap subtraction schemes to remove the ${\cal O}(\Lambda_{\rm QCD})$ renormalon related to large-angle soft radiation. These generalizations entail implementing a more versatile shape-function fit procedure and accounting for a certain type of $(m_t/Q)^2$ power corrections to achieve gap-scheme and observable independent results. The theoretical description employs boosted heavy-quark effective theory (bHQET) at next-to-next-to-logarithmic order (N$^2$LL), matched to soft-collinear effective theory (SCET) at N$^2$LL and full QCD at next-to-leading order (NLO), and includes the dominant top width effects. Furthermore, the software framework has been modernized to use standard file and event record formats. We update the top mass calibration results by applying the new framework to PYTHIA 8.205, HERWIG 7.2 and SHERPA 2.2.11. Even though the hadron-level resonance positions produced by the three generators differ significantly for the same top mass parameter $m_t^{\rm MC}$ value, the calibration shows that these differences arise from the hadronization modeling. Indeed, we find that $m_t^{\rm MC}$ agrees with $m_t^{\rm MSR}(1\,\mbox{GeV})$ within $200$ MeV for the three generators and differs from the pole mass by $350$ to $600$ MeV.
1110.4491
Yue-Liang Wu
Da Huang, Yue-Liang Wu
Chiral Thermodynamic Model of QCD and its Critical Behavior in the Closed-Time-Path Green Function Approach
29 pages, 5 figures, references and appendix added
null
null
null
hep-ph hep-th nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
By applying the closed-time-path Green function formalism to the chiral dynamical model based on an effective Lagrangian of chiral quarks with the nonlinear-realized meson fields as bosonized auxiliary fields, we then arrive at a chiral thermodynamic model for the meson fields with finite temperature. Particular attention is paid to the spontaneous chiral symmetry breaking and restoration from the dynamically generated effective composite Higgs potential of meson fields at finite temperature. It is shown that the minimal condition of the effective composite Higgs potential of meson fields leads to the thermodynamic gap equation at finite temperature, which enables us to investigate the critical behavior of the effective chiral thermodynamical model and to explore the QCD phase transition. After fixing the free parameters in the effective chiral Lagrangian at low energies with zero temperature, we determine the critical temperature of the chiral symmetry restoration and present a consistent prediction for the thermodynamical behavior of several physically interesting quantities, which include the vacuum expectation value $v_o(T)$, quark condensate $<\bar{q}q>(T)$, pion decay constant $f_\pi(T)$ and pion meson mass $m_{\pi}(T)$. In particular, it is also shown that the thermodynamic scaling behavior of these quantities becomes the same near the critical point of phase transition.
[ { "created": "Thu, 20 Oct 2011 11:01:24 GMT", "version": "v1" }, { "created": "Wed, 29 Feb 2012 00:44:44 GMT", "version": "v2" } ]
2012-03-02
[ [ "Huang", "Da", "" ], [ "Wu", "Yue-Liang", "" ] ]
By applying the closed-time-path Green function formalism to the chiral dynamical model based on an effective Lagrangian of chiral quarks with the nonlinear-realized meson fields as bosonized auxiliary fields, we then arrive at a chiral thermodynamic model for the meson fields with finite temperature. Particular attention is paid to the spontaneous chiral symmetry breaking and restoration from the dynamically generated effective composite Higgs potential of meson fields at finite temperature. It is shown that the minimal condition of the effective composite Higgs potential of meson fields leads to the thermodynamic gap equation at finite temperature, which enables us to investigate the critical behavior of the effective chiral thermodynamical model and to explore the QCD phase transition. After fixing the free parameters in the effective chiral Lagrangian at low energies with zero temperature, we determine the critical temperature of the chiral symmetry restoration and present a consistent prediction for the thermodynamical behavior of several physically interesting quantities, which include the vacuum expectation value $v_o(T)$, quark condensate $<\bar{q}q>(T)$, pion decay constant $f_\pi(T)$ and pion meson mass $m_{\pi}(T)$. In particular, it is also shown that the thermodynamic scaling behavior of these quantities becomes the same near the critical point of phase transition.
2008.12598
Jongkuk Kim
Yongsoo Jho, Jongkuk Kim, Pyungwon Ko, Seong Chan Park
Search for sterile neutrino with light gauge interactions: recasting collider, beam-dump, and neutrino telescope searches
9 pages, 4 figures, and 3 tables
null
null
KIAS-P20046, LDU-2020-07
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We investigate features of the sterile neutrinos in the presence of a light gauge boson $X^\mu$ that couples to the neutrino sector. The novel bounds on the active-sterile neutrino mixings $| U_{\ell 4} |^2$, especially for tau flavor ($l = \tau$), from various collider and fixed target experiments are explored. Also, taking into account the additional decay channel of the sterile neutrino into a light gauge boson ($\nu_4 \to \nu_\ell e^+ e^-$), we explore and constrain a parameter space for low energy excess in neutrino oscillation experiments.
[ { "created": "Fri, 28 Aug 2020 12:00:12 GMT", "version": "v1" } ]
2020-08-31
[ [ "Jho", "Yongsoo", "" ], [ "Kim", "Jongkuk", "" ], [ "Ko", "Pyungwon", "" ], [ "Park", "Seong Chan", "" ] ]
We investigate features of the sterile neutrinos in the presence of a light gauge boson $X^\mu$ that couples to the neutrino sector. The novel bounds on the active-sterile neutrino mixings $| U_{\ell 4} |^2$, especially for tau flavor ($l = \tau$), from various collider and fixed target experiments are explored. Also, taking into account the additional decay channel of the sterile neutrino into a light gauge boson ($\nu_4 \to \nu_\ell e^+ e^-$), we explore and constrain a parameter space for low energy excess in neutrino oscillation experiments.
hep-ph/0312162
Bo-Qiang Ma
Bo-Wen Xiao, Bo-Qiang Ma
Pion-photon and photon-pion transition form factors in light-cone formalism
20 pages, 2 figures
Phys.Rev.D68:034020,2003
10.1103/PhysRevD.68.034020
null
hep-ph hep-ex nucl-th
null
We derive the minimal Fock-state expansions of the pion and the photon wave functions in light-cone formalism, then we calculate the pion-photon and the photon-pion transition form factors of $\gamma ^{\ast}\pi ^{0}\to \gamma $ and $\gamma ^{\ast}\gamma \to \pi ^{0}$ processes by employing these quark-antiquark wave functions of the pion and the photon. We find that our calculation for the $\gamma ^{\ast}\gamma \to \pi ^{0}$ transition form factor agrees with the experimental data at low and moderately high energy scale. Moreover, the physical differences and inherent connections between the transition form factors of $\gamma ^{\ast}\pi ^{0}\to \gamma $ and $ \gamma ^{\ast}\gamma \to \pi ^{0}$ have been illustrated, which indicate that these two physical processes are intrinsically related. In addition, we also discuss the $\pi ^{0}\to \gamma \gamma $ form factor and the decay width $ \mathit{\Gamma}(\pi \to \gamma \gamma)$ at $Q^{2}=0$.
[ { "created": "Thu, 11 Dec 2003 21:59:26 GMT", "version": "v1" } ]
2010-01-18
[ [ "Xiao", "Bo-Wen", "" ], [ "Ma", "Bo-Qiang", "" ] ]
We derive the minimal Fock-state expansions of the pion and the photon wave functions in light-cone formalism, then we calculate the pion-photon and the photon-pion transition form factors of $\gamma ^{\ast}\pi ^{0}\to \gamma $ and $\gamma ^{\ast}\gamma \to \pi ^{0}$ processes by employing these quark-antiquark wave functions of the pion and the photon. We find that our calculation for the $\gamma ^{\ast}\gamma \to \pi ^{0}$ transition form factor agrees with the experimental data at low and moderately high energy scale. Moreover, the physical differences and inherent connections between the transition form factors of $\gamma ^{\ast}\pi ^{0}\to \gamma $ and $ \gamma ^{\ast}\gamma \to \pi ^{0}$ have been illustrated, which indicate that these two physical processes are intrinsically related. In addition, we also discuss the $\pi ^{0}\to \gamma \gamma $ form factor and the decay width $ \mathit{\Gamma}(\pi \to \gamma \gamma)$ at $Q^{2}=0$.
hep-ph/0602074
Marcos Rodriguez Cardoso
C.M. Maekawa and M. C. Rodriguez
Masses of Fermions in Supersymmetric Models
24 pages, 2 figures and 3 tables
JHEP 0604 (2006) 031
10.1088/1126-6708/2006/04/031
null
hep-ph
null
We consider the mass generation for the usual quarks and leptons in some supersymmetric models. The masses of the top, the bottom, the charm, the tau and the muon are given at the tree level. All the other quarks and the electron get their masses at the one loop level in the Minimal Supersymmetric Standard Model (MSSM) and in two Supersymmetric Left-Right Models, one model uses triplets (SUSYLRT) to break $SU(2)_{R}$-symmetry and the other use doublets(SUSYLRD).
[ { "created": "Wed, 8 Feb 2006 17:11:54 GMT", "version": "v1" } ]
2009-11-11
[ [ "Maekawa", "C. M.", "" ], [ "Rodriguez", "M. C.", "" ] ]
We consider the mass generation for the usual quarks and leptons in some supersymmetric models. The masses of the top, the bottom, the charm, the tau and the muon are given at the tree level. All the other quarks and the electron get their masses at the one loop level in the Minimal Supersymmetric Standard Model (MSSM) and in two Supersymmetric Left-Right Models, one model uses triplets (SUSYLRT) to break $SU(2)_{R}$-symmetry and the other use doublets(SUSYLRD).
hep-ph/9609240
Jim Cline
James M. Cline and Pierre-Anthony Lemieux
Electroweak Phase Transition in Two Higgs Doublet Models
18 pp., 5 figures, uses epsf.tex. Corrected matching conditions for analytic approximation to thermal effective potential, eq. (10), and typos in eq. (5)
Phys.Rev. D55 (1997) 3873-3881
10.1103/PhysRevD.55.3873
McGill 96-16
hep-ph
null
We reexamine the strength of the first order phase transition in the electroweak theory supplemented by an extra Higgs doublet. The finite-temperature effective potential, $V_{eff}$, is computed to one-loop order, including the summation of ring diagrams, to study the ratio $\phi_c/T_c$ of the Higgs field VEV to the critical temperature. We make a number of improvements over previous treatments, including a consistent treatment of Goldstone bosons in $V_{eff}$, an accurate analytic approximation to $V_{eff}$ valid for any mass-to-temperature ratios, and use of the experimentally measured top quark mass. For two-Higgs doublet models, we identify a significant region of parameter space where $\phi_c/T_c$ is large enough for electroweak baryogenesis, and we argue that this identification should persist even at higher orders in perturbation theory. In the case of the minimal supersymmetric standard model, our results indicate that the extra Higgs bosons have little effect on the strength of the phase transition.
[ { "created": "Tue, 3 Sep 1996 21:39:03 GMT", "version": "v1" }, { "created": "Fri, 27 Jul 2007 13:04:44 GMT", "version": "v2" }, { "created": "Thu, 23 Aug 2007 19:47:10 GMT", "version": "v3" } ]
2009-10-28
[ [ "Cline", "James M.", "" ], [ "Lemieux", "Pierre-Anthony", "" ] ]
We reexamine the strength of the first order phase transition in the electroweak theory supplemented by an extra Higgs doublet. The finite-temperature effective potential, $V_{eff}$, is computed to one-loop order, including the summation of ring diagrams, to study the ratio $\phi_c/T_c$ of the Higgs field VEV to the critical temperature. We make a number of improvements over previous treatments, including a consistent treatment of Goldstone bosons in $V_{eff}$, an accurate analytic approximation to $V_{eff}$ valid for any mass-to-temperature ratios, and use of the experimentally measured top quark mass. For two-Higgs doublet models, we identify a significant region of parameter space where $\phi_c/T_c$ is large enough for electroweak baryogenesis, and we argue that this identification should persist even at higher orders in perturbation theory. In the case of the minimal supersymmetric standard model, our results indicate that the extra Higgs bosons have little effect on the strength of the phase transition.
1608.08501
Olcyr Sumensari
Damir Be\v{c}irevi\'c, Svjetlana Fajfer, Nejc Ko\v{s}nik, Olcyr Sumensari
Leptoquark model to explain the $B$-physics anomalies, $R_K$ and $R_D$
6 pages, 4 figures
Phys. Rev. D 94, 115021 (2016)
10.1103/PhysRevD.94.115021
LPT-Orsay-16-51
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that a model with a scalar leptoquark of hypercharge $Y=1/6$ which includes the light right-handed neutrinos, can successfully describe both of the $B$-physics anomalies, $R_K^{\rm exp} < R_K^{\rm SM}$ and $R_D^{\rm exp} > R_D^{\rm SM}$. We discuss the corresponding low energy effective theory and, after using the known experimental data as constraints, we show that the model is viable and that it offers several predictions which can be tested experimentally.
[ { "created": "Tue, 30 Aug 2016 15:30:51 GMT", "version": "v1" } ]
2016-12-28
[ [ "Bečirević", "Damir", "" ], [ "Fajfer", "Svjetlana", "" ], [ "Košnik", "Nejc", "" ], [ "Sumensari", "Olcyr", "" ] ]
We show that a model with a scalar leptoquark of hypercharge $Y=1/6$ which includes the light right-handed neutrinos, can successfully describe both of the $B$-physics anomalies, $R_K^{\rm exp} < R_K^{\rm SM}$ and $R_D^{\rm exp} > R_D^{\rm SM}$. We discuss the corresponding low energy effective theory and, after using the known experimental data as constraints, we show that the model is viable and that it offers several predictions which can be tested experimentally.
hep-ph/9810254
Randy Lewis
Randy Lewis and Nader Mobed
Isospin violation and the proton's neutral weak magnetic form factor
26 pages including 9 figures
Phys.Rev.D59:073002,1999
10.1103/PhysRevD.59.073002
JLAB-THY-98-39
hep-ph nucl-th
null
The effects of isospin violation on the neutral weak magnetic form factor of the proton are studied using two-flavour chiral perturbation theory. The first nonzero contributions appear at O(p^4) in the small-momentum expansion, and the O(p^5) corrections are also calculated. The leading contributions from an explicit Delta(1232) isomultiplet are included as well. At such a high order in the chiral expansion, one might have expected a large number of unknown parameters to contribute. However, it is found that no unknown parameters can appear within loop diagrams, and a single tree-level counterterm at O(p^4) is sufficient to absorb all divergences. The momentum dependence of the neutral weak magnetic form factor is not affected by this counterterm.
[ { "created": "Mon, 5 Oct 1998 21:24:17 GMT", "version": "v1" } ]
2009-12-30
[ [ "Lewis", "Randy", "" ], [ "Mobed", "Nader", "" ] ]
The effects of isospin violation on the neutral weak magnetic form factor of the proton are studied using two-flavour chiral perturbation theory. The first nonzero contributions appear at O(p^4) in the small-momentum expansion, and the O(p^5) corrections are also calculated. The leading contributions from an explicit Delta(1232) isomultiplet are included as well. At such a high order in the chiral expansion, one might have expected a large number of unknown parameters to contribute. However, it is found that no unknown parameters can appear within loop diagrams, and a single tree-level counterterm at O(p^4) is sufficient to absorb all divergences. The momentum dependence of the neutral weak magnetic form factor is not affected by this counterterm.
2405.18226
Song Li
Song Li, Jin Min Yang, Mengchao Zhang, Rui Zhu
Theoretical bounds on dark Higgs mass in a self-interacting dark matter model with $U(1)'$
45 pages, 7 figures
null
null
null
hep-ph astro-ph.CO hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Motivated by the null results of current dark matter searches and the small-scale problems, we study a dark sector charged by a spontaneous broken gauge $U(1)'$. To explore the parameter space of this model, in addition to the consideration of the small-scale data, we also consider the theoretical bounds on the dark Higgs mass, with the upper bound coming from the tree-level perturbative unitarity and the lower bound from the one-loop Linde-Weinberg bound. We deeply examine the dependence of the Linde-Weinberg bound on gauge choice and energy scale, and present a Linde-Weinberg bound that is gauge and scale independent. Combining the theoretical and observational constraints, we obtain the following ranges for the parameter space: the dark matter mass is 10-500 GeV, the mediator (dark photon) mass is 0.5-5 MeV, the dark Higgs mass is 0.05-50 MeV, and the dark fine-structure constant is 0.001-0.4. We conclude that the dark Higgs in this model cannot be ignored in the phenomenological study of the dark sector.
[ { "created": "Tue, 28 May 2024 14:37:22 GMT", "version": "v1" }, { "created": "Mon, 29 Jul 2024 06:39:54 GMT", "version": "v2" } ]
2024-07-30
[ [ "Li", "Song", "" ], [ "Yang", "Jin Min", "" ], [ "Zhang", "Mengchao", "" ], [ "Zhu", "Rui", "" ] ]
Motivated by the null results of current dark matter searches and the small-scale problems, we study a dark sector charged by a spontaneous broken gauge $U(1)'$. To explore the parameter space of this model, in addition to the consideration of the small-scale data, we also consider the theoretical bounds on the dark Higgs mass, with the upper bound coming from the tree-level perturbative unitarity and the lower bound from the one-loop Linde-Weinberg bound. We deeply examine the dependence of the Linde-Weinberg bound on gauge choice and energy scale, and present a Linde-Weinberg bound that is gauge and scale independent. Combining the theoretical and observational constraints, we obtain the following ranges for the parameter space: the dark matter mass is 10-500 GeV, the mediator (dark photon) mass is 0.5-5 MeV, the dark Higgs mass is 0.05-50 MeV, and the dark fine-structure constant is 0.001-0.4. We conclude that the dark Higgs in this model cannot be ignored in the phenomenological study of the dark sector.
hep-ph/0110119
Liu Chun
Chun Liu and Jeonghyeon Song
A Phenomenological Study on Lepton Mass Matrix Textures
6 pages, revtex, no figures, confusing points corrected, clarification and refernces added
Phys.Rev.D65:057303,2002
10.1103/PhysRevD.65.057303
AS-ITP-2001-017
hep-ph
null
The three active light neutrinos are used to explain the neutrino oscillations. The inherently bi-large mixing neutrino mass matrix and the Fritzsch type, bi-small mixing charged lepton mass matrix are assumed. By requiring the maximal \nu_\mu-\nu_\tau mixing for the atmospheric neutrino problem and the mass-squared difference approperiate for the almost maximal mixing solution to the solar neutrino problem, the following quantities are predicted: the \nu_e-\nu_\mu mixing, V_{e3}, CP violation in neutrino oscillations, and the effective electron-neutrino mass relevant to neutrinoless double beta decays.
[ { "created": "Tue, 9 Oct 2001 10:51:44 GMT", "version": "v1" }, { "created": "Sat, 10 Nov 2001 14:14:35 GMT", "version": "v2" } ]
2014-11-17
[ [ "Liu", "Chun", "" ], [ "Song", "Jeonghyeon", "" ] ]
The three active light neutrinos are used to explain the neutrino oscillations. The inherently bi-large mixing neutrino mass matrix and the Fritzsch type, bi-small mixing charged lepton mass matrix are assumed. By requiring the maximal \nu_\mu-\nu_\tau mixing for the atmospheric neutrino problem and the mass-squared difference approperiate for the almost maximal mixing solution to the solar neutrino problem, the following quantities are predicted: the \nu_e-\nu_\mu mixing, V_{e3}, CP violation in neutrino oscillations, and the effective electron-neutrino mass relevant to neutrinoless double beta decays.
1605.06550
Monika Richter
Bartosz Dziewit, Jacek Holeczek, Monika Richter, Sebastian Zaj\k{a}c, Marek Zra{\l}ek
The flavour problem and family symmetry beyond the Standard Model
6 pages, topic presented at XXXIX International Conference of Theoretical Physics "Matter to the deepest" (Ustron, Poland, September 2015)
Acta Phys.Polon. B46 (2015) no.11, 2399 (2015)
10.5506/APhysPolB.46.2399
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the frame of two Higgs doublet model we try to explain the lepton masses and mixing matrix elements assuming that neutrinos are Dirac particles. Discrete family symmetry groups, which are subgroups of U(3) up to the 1025 order are considered. Like in the one Higgs Standard Model, we found that discrete family symmetries do not give satisfactory answer for this basic questions in the flavour problem.
[ { "created": "Fri, 20 May 2016 22:12:04 GMT", "version": "v1" }, { "created": "Sat, 18 Jun 2016 14:05:00 GMT", "version": "v2" } ]
2016-06-21
[ [ "Dziewit", "Bartosz", "" ], [ "Holeczek", "Jacek", "" ], [ "Richter", "Monika", "" ], [ "Zając", "Sebastian", "" ], [ "Zrałek", "Marek", "" ] ]
In the frame of two Higgs doublet model we try to explain the lepton masses and mixing matrix elements assuming that neutrinos are Dirac particles. Discrete family symmetry groups, which are subgroups of U(3) up to the 1025 order are considered. Like in the one Higgs Standard Model, we found that discrete family symmetries do not give satisfactory answer for this basic questions in the flavour problem.
hep-ph/9504375
null
C.H. Jin and E.A. Paschos
Inclusive Semileptonic Decays and the Structure of B Mesons
24 pages, LaTex file, 5 figures added as .EPS files
null
null
DO-TH 95/07
hep-ph
null
A field theoretic description for inclusive semileptonic B meson decays is formulated. We argue that large regions of the phase spaces for the decays are dominated by distances near the light cone. The light-cone dominance allows to incorporate nonperturbative QCD effects in a distribution function. A one-to-one correspondence with the heavy quark effective theory is developed, which can estimate the first two moments of the distribution function. These conditions are useful but not restrictive enough to specify the distribution function, which must still be determined from experiment. Several model-independent predictions, such as scaling, sum rules of the hadronic structure functions and relations among them, are made. General formulas for the differential decay rates on several variables are presented, which are used for calculating the electron energy spectra with an Ansatz for the light-cone distribution function.
[ { "created": "Mon, 24 Apr 1995 14:41:37 GMT", "version": "v1" } ]
2007-05-23
[ [ "Jin", "C. H.", "" ], [ "Paschos", "E. A.", "" ] ]
A field theoretic description for inclusive semileptonic B meson decays is formulated. We argue that large regions of the phase spaces for the decays are dominated by distances near the light cone. The light-cone dominance allows to incorporate nonperturbative QCD effects in a distribution function. A one-to-one correspondence with the heavy quark effective theory is developed, which can estimate the first two moments of the distribution function. These conditions are useful but not restrictive enough to specify the distribution function, which must still be determined from experiment. Several model-independent predictions, such as scaling, sum rules of the hadronic structure functions and relations among them, are made. General formulas for the differential decay rates on several variables are presented, which are used for calculating the electron energy spectra with an Ansatz for the light-cone distribution function.
2006.08490
David Arturo Amor Quiroz
David Arturo Amor-Quiroz, Matthias Burkardt, William Focillon and C\'edric Lorc\'e
Study of the potential transverse momentum and potential angular momentum within the scalar diquark model
Presented at the Workshop of QCD and Forward Physics at the EIC, the LHC, and Cosmic Ray Physics in Guanajuato, Mexico, November 18-21 2019
null
null
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We make use of a simple scalar diquark model to study the potential transverse momentum and potential angular momentum, defined as the difference between the Jaffe-Manohar and Ji notions of transverse momentum and orbital angular momentum, respectively. A non-vanishing potential angular momentum has been previously found in lattice calculations and is believed to appear due to the effects of initial/final state interactions between the spectator system and the struck quark in high energy scattering processes. Such re-scattering phenomena are similar in nature to those who are responsible for generating the Sivers shift. This motivates us to search for an estimate of the potential angular momentum in terms of the expectation value of the transverse momentum of the struck quark.
[ { "created": "Mon, 15 Jun 2020 15:48:45 GMT", "version": "v1" } ]
2020-06-16
[ [ "Amor-Quiroz", "David Arturo", "" ], [ "Burkardt", "Matthias", "" ], [ "Focillon", "William", "" ], [ "Lorcé", "Cédric", "" ] ]
We make use of a simple scalar diquark model to study the potential transverse momentum and potential angular momentum, defined as the difference between the Jaffe-Manohar and Ji notions of transverse momentum and orbital angular momentum, respectively. A non-vanishing potential angular momentum has been previously found in lattice calculations and is believed to appear due to the effects of initial/final state interactions between the spectator system and the struck quark in high energy scattering processes. Such re-scattering phenomena are similar in nature to those who are responsible for generating the Sivers shift. This motivates us to search for an estimate of the potential angular momentum in terms of the expectation value of the transverse momentum of the struck quark.
2404.07822
Benjamin Lieberman B
Benjamin Lieberman, Salah-Eddine Dahbi, Andreas Crivellin, Finn Stevenson, Nidhi Tripathi, Mukesh Kumar and Bruce Mellado
Trials Factor for Semi-Supervised NN Classifiers in Searches for Narrow Resonances at the LHC
21 pages, 14 figures, with few minor corrections
null
null
ICPP-80
hep-ph
http://creativecommons.org/publicdomain/zero/1.0/
To mitigate the model dependencies of searches for new narrow resonances at the Large Hadron Collider (LHC), semi-supervised Neural Networks (NNs) can be used. Unlike fully supervised classifiers these models introduce an additional look-elsewhere effect in the process of optimising thresholds on the response distribution. We perform a frequentist study to quantify this effect, in the form of a trials factor. As an example, we consider simulated $Z\gamma$ data to perform narrow resonance searches using semi-supervised NN classifiers. The results from this analysis provide substantiation that the look-elsewhere effect induced by the semi-supervised NN is under control.
[ { "created": "Thu, 11 Apr 2024 15:06:15 GMT", "version": "v1" }, { "created": "Thu, 27 Jun 2024 10:21:48 GMT", "version": "v2" }, { "created": "Thu, 8 Aug 2024 09:07:24 GMT", "version": "v3" } ]
2024-08-09
[ [ "Lieberman", "Benjamin", "" ], [ "Dahbi", "Salah-Eddine", "" ], [ "Crivellin", "Andreas", "" ], [ "Stevenson", "Finn", "" ], [ "Tripathi", "Nidhi", "" ], [ "Kumar", "Mukesh", "" ], [ "Mellado", "Bruce", "" ...
To mitigate the model dependencies of searches for new narrow resonances at the Large Hadron Collider (LHC), semi-supervised Neural Networks (NNs) can be used. Unlike fully supervised classifiers these models introduce an additional look-elsewhere effect in the process of optimising thresholds on the response distribution. We perform a frequentist study to quantify this effect, in the form of a trials factor. As an example, we consider simulated $Z\gamma$ data to perform narrow resonance searches using semi-supervised NN classifiers. The results from this analysis provide substantiation that the look-elsewhere effect induced by the semi-supervised NN is under control.
1210.0580
Thomas Becher
Thomas Becher and Guido Bell
NNLL Resummation for Jet Broadening
44 pages, 9 figures
null
10.1007/JHEP11(2012)126
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The resummation for the event-shape variable jet broadening is extended to next-to-next-to-leading logarithmic accuracy by computing the relevant jet and soft functions at one-loop order and the collinear anomaly to two-loop accuracy. The anomaly coefficient is extracted from the soft function and expressed in terms of polylogarithmic as well as elliptic functions. With our results, the uncertainty on jet-broadening distributions is reduced significantly, which should allow for a precise determination of the strong coupling constant from the existing experimental data and provide a consistency check on the extraction of alpha_s from higher-log resummations of thrust.
[ { "created": "Mon, 1 Oct 2012 21:10:53 GMT", "version": "v1" } ]
2015-06-11
[ [ "Becher", "Thomas", "" ], [ "Bell", "Guido", "" ] ]
The resummation for the event-shape variable jet broadening is extended to next-to-next-to-leading logarithmic accuracy by computing the relevant jet and soft functions at one-loop order and the collinear anomaly to two-loop accuracy. The anomaly coefficient is extracted from the soft function and expressed in terms of polylogarithmic as well as elliptic functions. With our results, the uncertainty on jet-broadening distributions is reduced significantly, which should allow for a precise determination of the strong coupling constant from the existing experimental data and provide a consistency check on the extraction of alpha_s from higher-log resummations of thrust.
2203.08039
Ian Shoemaker
Asli M. Abdullahi, Pablo Barham Alzas, Brian Batell, Alexey Boyarsky, Saneli Carbajal, Animesh Chatterjee, Jose I. Crespo-Anadon, Frank F. Deppisch, Albert De Roeck, Marco Drewes, Alberto Martin Gago, Rebeca Gonzalez Suarez, Evgueni Goudzovski, Athanasios Hatzikoutelis, Marco Hufnagel, Philip Ilten, Alexander Izmaylov, Kevin J. Kelly, Juraj Klaric, Joachim Kopp, Suchita Kulkarni, Mathieu Lamoureux, Gaia Lanfranchi, Jacobo Lopez-Pavon, Oleksii Mikulenko, Michael Mooney, Miha Nemevsek, Maksym Ovchynnikov, Silvia Pascoli, Ryan Plestid, Mohamed Rashad Darwish, Federico Leo Redi, Oleg Ruchayskiy, Richard Ruiz, Mikhail Shaposhnikov, Ian M. Shoemaker, Robert Shrock, Alex Sousa, Nick Van Remortel, Vsevolod Syvolap, Volodymyr Takhistov, Jean-Loup Tastet, Inar Timiryasov, Aaron C. Vincent, Jaehoon Yu
The Present and Future Status of Heavy Neutral Leptons
82 pages, 34 figures. Contribution to Snowmass 2021
null
10.1088/1361-6471/ac98f9
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
The existence of non-zero neutrino masses points to the likely existence of multiple SM neutral fermions. When such states are heavy enough that they cannot be produced in oscillations, they are referred to as Heavy Neutral Leptons (HNLs). In this white paper we discuss the present experimental status of HNLs including colliders, beta decay, accelerators, as well as astrophysical and cosmological impacts. We discuss the importance of continuing to search for HNLs, and its potential impact on our understanding on key fundamental questions, and additionally we outline the future prospects for next-generation future experiments or upcoming accelerator run scenarios.
[ { "created": "Tue, 15 Mar 2022 16:21:35 GMT", "version": "v1" } ]
2023-02-01
[ [ "Abdullahi", "Asli M.", "" ], [ "Alzas", "Pablo Barham", "" ], [ "Batell", "Brian", "" ], [ "Boyarsky", "Alexey", "" ], [ "Carbajal", "Saneli", "" ], [ "Chatterjee", "Animesh", "" ], [ "Crespo-Anadon", "Jose I....
The existence of non-zero neutrino masses points to the likely existence of multiple SM neutral fermions. When such states are heavy enough that they cannot be produced in oscillations, they are referred to as Heavy Neutral Leptons (HNLs). In this white paper we discuss the present experimental status of HNLs including colliders, beta decay, accelerators, as well as astrophysical and cosmological impacts. We discuss the importance of continuing to search for HNLs, and its potential impact on our understanding on key fundamental questions, and additionally we outline the future prospects for next-generation future experiments or upcoming accelerator run scenarios.
2401.15651
Yanbing Cai
Yanbing Cai, Xiaopeng Wang, Xurong Chen
New exact analytical solution of the nonlinear Gribov-Levin-Ryskin-Mueller-Qiu equation
13 pages, 3 figures
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The GLR-MQ equation is a nonlinear evolution equation that takes into account the shadowing effect, which tames the growth of the gluon at small-$x$. In this study, we analytically solve for the first time the nonlinear GLR-MQ equation using the homogeneous balance method. The definite solution of the GLR-MQ equation is obtained by fitting the MSTW2008LO gluon distribution data. We find that the geometric scaling is an intrinsic property of our analytical solution and the gluon distribution functions from our solution are able to reproduce the MSTW2008LO data. These results indicate that our analytical solution from the homogeneous balance method is valid to describe the gluon behavior at small-$x$. Moreover, the saturation scale $Q_s$ has been extracted from our analytical solution, we find that the energy-dependent saturation scale obeys the exponential law $Q_s^2\,\propto\,Q_0^2 e^{\lambda Y}$.
[ { "created": "Sun, 28 Jan 2024 13:00:30 GMT", "version": "v1" } ]
2024-01-30
[ [ "Cai", "Yanbing", "" ], [ "Wang", "Xiaopeng", "" ], [ "Chen", "Xurong", "" ] ]
The GLR-MQ equation is a nonlinear evolution equation that takes into account the shadowing effect, which tames the growth of the gluon at small-$x$. In this study, we analytically solve for the first time the nonlinear GLR-MQ equation using the homogeneous balance method. The definite solution of the GLR-MQ equation is obtained by fitting the MSTW2008LO gluon distribution data. We find that the geometric scaling is an intrinsic property of our analytical solution and the gluon distribution functions from our solution are able to reproduce the MSTW2008LO data. These results indicate that our analytical solution from the homogeneous balance method is valid to describe the gluon behavior at small-$x$. Moreover, the saturation scale $Q_s$ has been extracted from our analytical solution, we find that the energy-dependent saturation scale obeys the exponential law $Q_s^2\,\propto\,Q_0^2 e^{\lambda Y}$.
1605.08579
A. Cooper-Sarkar
A.M.Cooper-Sarkar (for the LHeC study group)
Improved measurement of parton distribution functions and $\alpha_s(M_Z)$ with the LHeC
6 pages, 8 figures, proceedings of the XXIV International Workshop on Deep-Inelastic Scattering and Related Subjects. arXiv admin note: substantial text overlap with arXiv:1310.0662
null
null
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The potential of the LHeC, a future electron-proton collider, for precision Deep Inelastic Scattering measurements is reviewed with particular emphasis on the reduction of uncertainties on the parton distribution functions (PDFs) of the proton and on the measurement of $\alpha_s(M_Z)$. The interpretation of possible Beyond Standard Model (BSM) signals at the LHC is crucially dependent on precise knowledge of the predictions of the Standard Model (SM) and the uncertainties on PDFs and $\alpha_s(M_Z) $are a limiting factor. The LHeC project, running in parallel with later stages of LHC running, would provide much improved precision on the PDFs as compared to the precision expected from LHC data alone.
[ { "created": "Fri, 27 May 2016 11:00:55 GMT", "version": "v1" } ]
2019-08-14
[ [ "Cooper-Sarkar", "A. M.", "", "for the LHeC study group" ] ]
The potential of the LHeC, a future electron-proton collider, for precision Deep Inelastic Scattering measurements is reviewed with particular emphasis on the reduction of uncertainties on the parton distribution functions (PDFs) of the proton and on the measurement of $\alpha_s(M_Z)$. The interpretation of possible Beyond Standard Model (BSM) signals at the LHC is crucially dependent on precise knowledge of the predictions of the Standard Model (SM) and the uncertainties on PDFs and $\alpha_s(M_Z) $are a limiting factor. The LHeC project, running in parallel with later stages of LHC running, would provide much improved precision on the PDFs as compared to the precision expected from LHC data alone.
hep-ph/0210199
Karol Kolodziej
Karol Kolodziej
eett6f v. 1.0, A program for top quark pair production and decay into 6 fermions at linear colliders
19 pages, submitted to Comput. Phys. Commun
Comput.Phys.Commun. 151 (2003) 339-353
10.1016/S0010-4655(02)00738-5
null
hep-ph
null
The first version of a computer program "eett6f" for calculating cross sections of e+e- -> 6 fermions processes relevant for a t\bar{t}-pair production and decay at centre of mass energies typical for linear colliders is presented. "eett6f v.~1.0" allows for calculating both the total and differential cross sections at tree level of the Standard Model. The program can be used as the Monte Carlo generator of unweighted events as well.
[ { "created": "Mon, 14 Oct 2002 08:49:44 GMT", "version": "v1" } ]
2009-11-07
[ [ "Kolodziej", "Karol", "" ] ]
The first version of a computer program "eett6f" for calculating cross sections of e+e- -> 6 fermions processes relevant for a t\bar{t}-pair production and decay at centre of mass energies typical for linear colliders is presented. "eett6f v.~1.0" allows for calculating both the total and differential cross sections at tree level of the Standard Model. The program can be used as the Monte Carlo generator of unweighted events as well.
0802.2954
Kirill Tuchin
Yang Li, Kirill Tuchin
Gluon multiplicity in coherent diffraction of onium on a heavy nucleus
21 pages, 5 figures
Phys.Rev.D77:114012,2008
10.1103/PhysRevD.77.114012
RBRC-729
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We derive the cross section for the diffractive gluon production in high energy onium-nucleus collisions that includes the low-x evolution effects in the rapidity interval between the onium and the produced gluon and in the rapidity interval between the gluon and the target nucleus. We analyze our result in two limiting cases: when the onium size is much smaller than the saturation scale and when its size is much larger than the saturation scale. In the later case the gluon multiplicity is very small in the quasi-classical case and increases when the low-x evolution effects in onium become significant. We discuss the implications of our result for the RHIC, LHC and EIC phenomenology.
[ { "created": "Wed, 20 Feb 2008 22:21:36 GMT", "version": "v1" }, { "created": "Wed, 23 Apr 2008 15:46:09 GMT", "version": "v2" } ]
2008-11-26
[ [ "Li", "Yang", "" ], [ "Tuchin", "Kirill", "" ] ]
We derive the cross section for the diffractive gluon production in high energy onium-nucleus collisions that includes the low-x evolution effects in the rapidity interval between the onium and the produced gluon and in the rapidity interval between the gluon and the target nucleus. We analyze our result in two limiting cases: when the onium size is much smaller than the saturation scale and when its size is much larger than the saturation scale. In the later case the gluon multiplicity is very small in the quasi-classical case and increases when the low-x evolution effects in onium become significant. We discuss the implications of our result for the RHIC, LHC and EIC phenomenology.
1101.5158
Moritz McGarrie
Moritz McGarrie
Hybrid Gauge Mediation
20 pages, 10 figures. Version accepted by JHEP
null
10.1007/JHEP09(2011)138
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Inspired by four dimensional (de)constructions, we use the framework of "General gauge mediation in five dimensions" to interpolate between gaugino and ordinary gauge mediation. In particular we emphasise that an intermediate hybrid regime of mediation may be obtained in these higher dimensional models as has been obtained in the quiver gauge models.
[ { "created": "Wed, 26 Jan 2011 21:00:10 GMT", "version": "v1" }, { "created": "Mon, 19 Sep 2011 15:53:08 GMT", "version": "v2" } ]
2015-05-27
[ [ "McGarrie", "Moritz", "" ] ]
Inspired by four dimensional (de)constructions, we use the framework of "General gauge mediation in five dimensions" to interpolate between gaugino and ordinary gauge mediation. In particular we emphasise that an intermediate hybrid regime of mediation may be obtained in these higher dimensional models as has been obtained in the quiver gauge models.
2202.09358
Stanley Deser
S.Deser
The Anthropic (and Mis-) Principle revisited, Steven Weinberg in Memoriam
published version
EPL 139, 6902(2022)
10.1209/0295-5075/ac8e29
BRX-TH-6702; CALT-TH-2022-008
hep-ph gr-qc
http://creativecommons.org/licenses/by/4.0/
I review the role and meaning of the Anthropic Principle, particularly in its relevance to particle physics.
[ { "created": "Fri, 18 Feb 2022 21:30:14 GMT", "version": "v1" }, { "created": "Thu, 8 Dec 2022 00:36:19 GMT", "version": "v2" } ]
2022-12-12
[ [ "Deser", "S.", "" ] ]
I review the role and meaning of the Anthropic Principle, particularly in its relevance to particle physics.
hep-ph/0604043
Johan Bijnens
Johan Bijnens (Lund)
Chiral Perturbation Theory Beyond One Loop
66 pages, review article, some references added plus a few discussions extended
Prog.Part.Nucl.Phys.58:521-586,2007
10.1016/j.ppnp.2006.08.002
LU TP 06-16
hep-ph
null
The existing Chiral Perturbation Theory (ChPT) calculations at order $p^6$ are reviewed. The principles of ChPT and how they are used are introduced. The main part is a review of the two- and three-flavour full two-loop calculations and their comparison with experiment. We restrict the discussion to the mesonic purely strong and semileptonic sector. The review concludes by mentioning the existing results in finite volume, finite temperature and partially quenched ChPT.
[ { "created": "Wed, 5 Apr 2006 12:10:46 GMT", "version": "v1" }, { "created": "Tue, 1 Aug 2006 09:12:10 GMT", "version": "v2" } ]
2008-11-26
[ [ "Bijnens", "Johan", "", "Lund" ] ]
The existing Chiral Perturbation Theory (ChPT) calculations at order $p^6$ are reviewed. The principles of ChPT and how they are used are introduced. The main part is a review of the two- and three-flavour full two-loop calculations and their comparison with experiment. We restrict the discussion to the mesonic purely strong and semileptonic sector. The review concludes by mentioning the existing results in finite volume, finite temperature and partially quenched ChPT.
1811.01948
Graham White Dr
Anupam Mazumdar and Graham White
Cosmic phase transitions: their applications and experimental signatures
87 pages, 35 figures, review. Converted to JHEP format for compatibility and convenience with lower quality figures to keep file size manageable. Accepted version. Added citations, fixed a few typos and added a well deserved acknowledgement
null
10.1088/1361-6633/ab1f55
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The study of cosmic phase transitions are of central interest in modern cosmology. In the standard model of cosmology the Universe begins in a very hot state, right after at the end of inflation via the process of reheating/preheating, and cools to its present temperature as the Universe expands. Both new and existing physics at any scale can be responsible for catalyzing either first, second or cross over phase transition, which could be either thermal or non-thermal with a potential observable imprints. Thus this field prompts a rich dialogue between gravity, particle physics and cosmology. It is all but certain that at least two cosmic phase transitions have occurred - the electroweak and the QCD phase transitions. The focus of this review will be primarily on phase transitions above such scales, We review different types of phase transitions that can appear in our cosmic history, and their applications and experimental signatures in particular in the context of exciting gravitational waves, which could be potentially be constrained by LIGO/VIRGO, Kagra, and eLISA.
[ { "created": "Mon, 5 Nov 2018 19:00:00 GMT", "version": "v1" }, { "created": "Mon, 6 May 2019 19:10:34 GMT", "version": "v2" }, { "created": "Wed, 18 Dec 2019 20:09:18 GMT", "version": "v3" } ]
2019-12-20
[ [ "Mazumdar", "Anupam", "" ], [ "White", "Graham", "" ] ]
The study of cosmic phase transitions are of central interest in modern cosmology. In the standard model of cosmology the Universe begins in a very hot state, right after at the end of inflation via the process of reheating/preheating, and cools to its present temperature as the Universe expands. Both new and existing physics at any scale can be responsible for catalyzing either first, second or cross over phase transition, which could be either thermal or non-thermal with a potential observable imprints. Thus this field prompts a rich dialogue between gravity, particle physics and cosmology. It is all but certain that at least two cosmic phase transitions have occurred - the electroweak and the QCD phase transitions. The focus of this review will be primarily on phase transitions above such scales, We review different types of phase transitions that can appear in our cosmic history, and their applications and experimental signatures in particular in the context of exciting gravitational waves, which could be potentially be constrained by LIGO/VIRGO, Kagra, and eLISA.
1510.05797
Luca Silvestrini
Luca Silvestrini
CHARM-2015 Theory Summary
To be published in the proceedings of CHARM-2015, Detroit, MI, 18-22 May 2015
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I present a brief theory overview of the CHARM-2015 conference.
[ { "created": "Tue, 20 Oct 2015 08:57:47 GMT", "version": "v1" } ]
2015-10-21
[ [ "Silvestrini", "Luca", "" ] ]
I present a brief theory overview of the CHARM-2015 conference.
hep-ph/0512009
Ferruccio Feruglio
Ferruccio Feruglio
Maximal Neutrino Mixing from Discrete Symmetry in Extra Dimensions
3 pages, 1 figure, contribution to proc. of the Int. Europhysics Conf. on High Energy Physics (HEP2005) July 21th-27th 2005, Lisboa, Portugal
null
null
PoS(HEP2005)185
hep-ph
null
I review the construction of a model for lepton masses based on the flavour symmetry group A4 x U(1) reproducing the so-called tri-bimaximal lepton mixing scheme, in eccelent agreement with current data. The model predicts a neutrino spectrum of normal hierarchy type, not far from degenerate. A testable relation between neutrino masses is obtained. I shortly discuss also general requirements for models based on spontaneously broken flavour symmetries, in order to get a maximal atmospheric mixing angle.
[ { "created": "Thu, 1 Dec 2005 10:41:16 GMT", "version": "v1" } ]
2009-04-25
[ [ "Feruglio", "Ferruccio", "" ] ]
I review the construction of a model for lepton masses based on the flavour symmetry group A4 x U(1) reproducing the so-called tri-bimaximal lepton mixing scheme, in eccelent agreement with current data. The model predicts a neutrino spectrum of normal hierarchy type, not far from degenerate. A testable relation between neutrino masses is obtained. I shortly discuss also general requirements for models based on spontaneously broken flavour symmetries, in order to get a maximal atmospheric mixing angle.
1707.06906
Jun Song
Xing-rui Gou, Feng-lan Shao, Rui-qin Wang, Hai-hong Li, and Jun Song
New insights into hadron production mechanism from $p_{T}$ spectra in $pp$ collisions at $\sqrt{s}=7$ TeV
11 pages, 10 figures
Phys. Rev. D 96, 094010 (2017)
10.1103/PhysRevD.96.094010
null
hep-ph nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We show that the experimental data of mid-rapidity $p_{T}$ spectra for proton, $\Lambda$, $\Xi$ , $\Omega^{-}$, $\text{K(892)}^{*0}$ and $\Xi(1530)^{*0}$ in minimum-bias $pp$ collisions at $\sqrt{s}=7$ TeV can be systemically explained by the quark combination mechanism of hadronization. The averaged transverse momentum $\langle p_{T}\rangle$ and spectra ratios such as $\Xi/\Lambda$ and $\Omega/\phi$ calculated from quark combination reproduce the data much better than those from traditional string and/or cluster fragmentation. The available data of hadronic $p_{T}$ spectra released by ALICE collaboration in the first three high-multiplicity classes of $pp$ collisions at $\sqrt{s}=7$ TeV are also well explained. We make predictions for other hadrons, and propose two scaling behaviors among decuplet baryons and vector mesons as the effective probe of hadron production mechanism at such high collision energy.
[ { "created": "Fri, 21 Jul 2017 14:05:00 GMT", "version": "v1" }, { "created": "Sat, 19 Aug 2017 02:56:56 GMT", "version": "v2" } ]
2017-11-22
[ [ "Gou", "Xing-rui", "" ], [ "Shao", "Feng-lan", "" ], [ "Wang", "Rui-qin", "" ], [ "Li", "Hai-hong", "" ], [ "Song", "Jun", "" ] ]
We show that the experimental data of mid-rapidity $p_{T}$ spectra for proton, $\Lambda$, $\Xi$ , $\Omega^{-}$, $\text{K(892)}^{*0}$ and $\Xi(1530)^{*0}$ in minimum-bias $pp$ collisions at $\sqrt{s}=7$ TeV can be systemically explained by the quark combination mechanism of hadronization. The averaged transverse momentum $\langle p_{T}\rangle$ and spectra ratios such as $\Xi/\Lambda$ and $\Omega/\phi$ calculated from quark combination reproduce the data much better than those from traditional string and/or cluster fragmentation. The available data of hadronic $p_{T}$ spectra released by ALICE collaboration in the first three high-multiplicity classes of $pp$ collisions at $\sqrt{s}=7$ TeV are also well explained. We make predictions for other hadrons, and propose two scaling behaviors among decuplet baryons and vector mesons as the effective probe of hadron production mechanism at such high collision energy.
0811.0394
Puneet Batra
Puneet Batra, Z. Chacko
A Composite Twin Higgs Model
6 pages, 1 figure
Phys.Rev.D79:095012,2009
10.1103/PhysRevD.79.095012
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Twin Higgs models are economical extensions of the Standard Model that stabilize the electroweak scale. In these theories the Higgs field is a pseudo Nambu-Goldstone boson that is protected against radiative corrections up to scales of order 5 TeV by a discrete parity symmetry. We construct, for the first time, a class of composite twin Higgs models based on confining QCD-like dynamics. These theories naturally incoporate a custodial isospin symmetry and predict a rich spectrum of particles with masses of order a TeV that will be accessible at the LHC.
[ { "created": "Mon, 3 Nov 2008 21:07:51 GMT", "version": "v1" } ]
2009-07-30
[ [ "Batra", "Puneet", "" ], [ "Chacko", "Z.", "" ] ]
Twin Higgs models are economical extensions of the Standard Model that stabilize the electroweak scale. In these theories the Higgs field is a pseudo Nambu-Goldstone boson that is protected against radiative corrections up to scales of order 5 TeV by a discrete parity symmetry. We construct, for the first time, a class of composite twin Higgs models based on confining QCD-like dynamics. These theories naturally incoporate a custodial isospin symmetry and predict a rich spectrum of particles with masses of order a TeV that will be accessible at the LHC.
2307.05176
David Alonso-Gonz\'alez
David Alonso-Gonz\'alez, Dorian W. P. Amaral, Adriana Bariego-Quintana, David Cerdeno and Mart\'in de los Rios
Measuring the Sterile Neutrino Mass in Spallation Source and Direct Detection Experiments
22 pages, 10 figures. Minor changes
null
null
IFT-UAM/CSIC-23-89
hep-ph astro-ph.CO
http://creativecommons.org/licenses/by/4.0/
We explore the complementarity of direct detection (DD) and spallation source (SS) experiments for the study of sterile neutrino physics. We focus on the sterile baryonic neutrino model: an extension of the Standard Model that introduces a massive sterile neutrino with couplings to the quark sector via a new gauge boson. In this scenario, the inelastic scattering of an active neutrino with the target material in both DD and SS experiments gives rise to a characteristic nuclear recoil energy spectrum that can allow for the reconstruction of the neutrino mass in the event of a positive detection. We first derive new bounds on this model based on the data from the COHERENT collaboration on CsI and LAr targets, which we find do not yet probe new areas of the parameter space. We then assess how well future SS experiments will be able to measure the sterile neutrino mass and mixings, showing that masses in the range 15-50 MeV can be reconstructed. We show that there is a degeneracy in the measurement of the sterile neutrino mixing that substantially affects the reconstruction of parameters for masses of the order of 40 MeV. Thanks to their lower energy threshold and sensitivity to the solar tau neutrino flux, DD experiments allow us to partially lift the degeneracy in the sterile neutrino mixings and considerably improve its mass reconstruction down to 9 MeV. Our results demonstrate the excellent complementarity between DD and SS experiments in measuring the sterile neutrino mass and highlight the power of DD experiments in searching for new physics in the neutrino sector.
[ { "created": "Tue, 11 Jul 2023 11:14:39 GMT", "version": "v1" }, { "created": "Wed, 2 Aug 2023 10:58:18 GMT", "version": "v2" } ]
2023-08-03
[ [ "Alonso-González", "David", "" ], [ "Amaral", "Dorian W. P.", "" ], [ "Bariego-Quintana", "Adriana", "" ], [ "Cerdeno", "David", "" ], [ "Rios", "Martín de los", "" ] ]
We explore the complementarity of direct detection (DD) and spallation source (SS) experiments for the study of sterile neutrino physics. We focus on the sterile baryonic neutrino model: an extension of the Standard Model that introduces a massive sterile neutrino with couplings to the quark sector via a new gauge boson. In this scenario, the inelastic scattering of an active neutrino with the target material in both DD and SS experiments gives rise to a characteristic nuclear recoil energy spectrum that can allow for the reconstruction of the neutrino mass in the event of a positive detection. We first derive new bounds on this model based on the data from the COHERENT collaboration on CsI and LAr targets, which we find do not yet probe new areas of the parameter space. We then assess how well future SS experiments will be able to measure the sterile neutrino mass and mixings, showing that masses in the range 15-50 MeV can be reconstructed. We show that there is a degeneracy in the measurement of the sterile neutrino mixing that substantially affects the reconstruction of parameters for masses of the order of 40 MeV. Thanks to their lower energy threshold and sensitivity to the solar tau neutrino flux, DD experiments allow us to partially lift the degeneracy in the sterile neutrino mixings and considerably improve its mass reconstruction down to 9 MeV. Our results demonstrate the excellent complementarity between DD and SS experiments in measuring the sterile neutrino mass and highlight the power of DD experiments in searching for new physics in the neutrino sector.
hep-ph/0610116
Paul Frampton
P.H. frampton
Proton Decay in Teravolt Unification
4 pages latex
Mod.Phys.Lett.A22:347-350,2007
10.1142/S0217732307022761
null
hep-ph astro-ph hep-th
null
Model building based on abelian quiver gauge theories gives models which resemble trinification, originally proposed with yottavolt unification. However, unification occurs in the teravolt range so proton decay must be completely excluded in the scalar sector. It is straightforward to accomplish this by a discrete symmetry which is a generalized baryon number B. Unlike in trinification, this is possible because quarks and leptons acquire masses from relevant operators which appear in four-dimensional conformal symmetry breaking.
[ { "created": "Tue, 10 Oct 2006 19:50:29 GMT", "version": "v1" } ]
2008-11-26
[ [ "frampton", "P. H.", "" ] ]
Model building based on abelian quiver gauge theories gives models which resemble trinification, originally proposed with yottavolt unification. However, unification occurs in the teravolt range so proton decay must be completely excluded in the scalar sector. It is straightforward to accomplish this by a discrete symmetry which is a generalized baryon number B. Unlike in trinification, this is possible because quarks and leptons acquire masses from relevant operators which appear in four-dimensional conformal symmetry breaking.
hep-ph/9807508
Cao Jun
Jun Cao, Fu-Guang Cao, Tao Huang, and Bo-Qiang Ma
Electromagnetic Transition Form Factor of Pseudoscalar Meson and $\eta-\eta'$ Mixing
13 pages, RevTeX, 4 ps figures, to appear in Phys. Rev. D
Phys.Rev. D58 (1998) 113006
10.1103/PhysRevD.58.113006
BIHEP-TH-97-21
hep-ph
null
The electromagnetic transition form factors of $\eta$ and $\eta'$ are calculated in the light-cone perturbation theory. We show that it is unreliable to determine the \eta-\etap'$ mixing angle without any additional normalization conditions other than their decay widthes to two photons. The possible intrinsic $c\bar{c}$ component in the flavor singlet is investigated. The heavy quark pair has distinct properties from the light ones in electromagnetic transition processes of pseudoscalar mesons. It is possible to explore the size of $c\bar{c}$ component and our numerical results disfavor a large portion of $c\bar{c}$ component.
[ { "created": "Mon, 27 Jul 1998 11:17:21 GMT", "version": "v1" } ]
2009-10-31
[ [ "Cao", "Jun", "" ], [ "Cao", "Fu-Guang", "" ], [ "Huang", "Tao", "" ], [ "Ma", "Bo-Qiang", "" ] ]
The electromagnetic transition form factors of $\eta$ and $\eta'$ are calculated in the light-cone perturbation theory. We show that it is unreliable to determine the \eta-\etap'$ mixing angle without any additional normalization conditions other than their decay widthes to two photons. The possible intrinsic $c\bar{c}$ component in the flavor singlet is investigated. The heavy quark pair has distinct properties from the light ones in electromagnetic transition processes of pseudoscalar mesons. It is possible to explore the size of $c\bar{c}$ component and our numerical results disfavor a large portion of $c\bar{c}$ component.
1609.03403
Jihn E. Kim
Jihn E. Kim
Type-II Leptogenesis
5 pages with 5 figures. Talk presented at ICHEP 2016, Chicago, August 6, 2016
null
null
null
hep-ph astro-ph.CO
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
I will talk on our new theory on baryogenesis through type-II leptogenesis which is different from the well-known type-I leptogenesis. I will comment on the Jarlskog phases, $\delta_{\rm CKM}$ and $\delta_{\rm PMNS}$, in the CKM and PMNS matrices. In the type-II leptogenesis, the PMNS phase is used for Sakharov's condition on the global quantum number generation in the Universe. For this to be effective, the SU(2)$\times$U(1) gauge symmetry must be broken during the leptogenesis epoch.
[ { "created": "Mon, 12 Sep 2016 13:55:39 GMT", "version": "v1" }, { "created": "Sun, 18 Sep 2016 21:14:11 GMT", "version": "v2" } ]
2016-09-20
[ [ "Kim", "Jihn E.", "" ] ]
I will talk on our new theory on baryogenesis through type-II leptogenesis which is different from the well-known type-I leptogenesis. I will comment on the Jarlskog phases, $\delta_{\rm CKM}$ and $\delta_{\rm PMNS}$, in the CKM and PMNS matrices. In the type-II leptogenesis, the PMNS phase is used for Sakharov's condition on the global quantum number generation in the Universe. For this to be effective, the SU(2)$\times$U(1) gauge symmetry must be broken during the leptogenesis epoch.
1304.7885
Yoshiharu Kawamura
Yoshiharu Kawamura
Tera Scale Remnants of Unification and Supersymmetry at Planck Scale
6 pages; minor changes, reference added, typos corrected
null
10.1093/ptep/ptt055
null
hep-ph hep-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We predict new particles at the Tera scale based on the assumptions that the standard model gauge interactions are unified around the gravitational scale with a big desert and new particles originate from hypermultiplets as remnants of supersymmetry, and propose a theoretical framework at the Tera scale and beyond, that has predictability.
[ { "created": "Tue, 30 Apr 2013 05:33:23 GMT", "version": "v1" }, { "created": "Mon, 6 May 2013 00:47:31 GMT", "version": "v2" } ]
2016-06-21
[ [ "Kawamura", "Yoshiharu", "" ] ]
We predict new particles at the Tera scale based on the assumptions that the standard model gauge interactions are unified around the gravitational scale with a big desert and new particles originate from hypermultiplets as remnants of supersymmetry, and propose a theoretical framework at the Tera scale and beyond, that has predictability.
hep-ph/0609068
Gabriel Shaughnessy
Vernon Barger, Paul Langacker, and Gabe Shaughnessy
Neutralino Signatures of the Singlet Extended MSSM
v1: 19 pages, 6 figures. v2: PLB version
Phys.Lett.B644:361-369,2007
10.1016/j.physletb.2006.11.043
MADPH-1471, UPR-1160-T
hep-ph
null
Extending the Higgs sector of the MSSM by the addition of a gauge singlet scalar field can remedy the mu problem. We explore the implications of extended models for both the spectrum of the neutralinos and the cascade decays of the neutralinos and charginos. Extra steps due to light decoupled neutralinos in the cascade decays of both neutralinos and charginos allow an excess of trilepton events compared to the MSSM and the existence of events with higher lepton multiplicity. Additionally, displaced vertices of the chi_2^0 due to small decay widths in some models may be observable.
[ { "created": "Wed, 6 Sep 2006 23:31:45 GMT", "version": "v1" }, { "created": "Thu, 9 Nov 2006 06:19:45 GMT", "version": "v2" } ]
2008-11-26
[ [ "Barger", "Vernon", "" ], [ "Langacker", "Paul", "" ], [ "Shaughnessy", "Gabe", "" ] ]
Extending the Higgs sector of the MSSM by the addition of a gauge singlet scalar field can remedy the mu problem. We explore the implications of extended models for both the spectrum of the neutralinos and the cascade decays of the neutralinos and charginos. Extra steps due to light decoupled neutralinos in the cascade decays of both neutralinos and charginos allow an excess of trilepton events compared to the MSSM and the existence of events with higher lepton multiplicity. Additionally, displaced vertices of the chi_2^0 due to small decay widths in some models may be observable.
1001.3554
Andreas Vogt
A. Vogt (Liverpool Univ.), S. Moch (DESY, Zeuthen), G. Soar (Liverpool Univ.) and J.A.M. Vermaseren (NIKHEF, Amsterdam)
Higher-order predictions for splitting functions and coefficient functions from physical evolution kernels
7 pages, LaTeX (PoS style). Presented by A.V. at RADCOR 2009, Ascona (Switzerland), October 2009. Too appear in the proceedings
null
null
LTH 862, DESY 10-007
hep-ph
http://creativecommons.org/licenses/by-nc-sa/3.0/
We have studied the physical evolution kernels for nine non-singlet observables in deep-inelastic scattering (DIS), semi-inclusive e^+e^-annihilation and the Drell-Yan (DY) process, and for the flavour-singlet case of the photon- and heavy-top Higgs-exchange structure functions (F_2, F_phi) in DIS. All known contributions to these kernels show an only single-logarithmic large-x enhancement at all powers of 1-x. Conjecturing that this behaviour persists to (all) higher orders, we have predicted the highest three (DY: two) double logarithms of the higher-order non-singlet coefficient functions and of the four-loop singlet splitting functions. The coefficient-function predictions canbe written as exponentiations of 1/N-suppressed contributions in Mellin-N space which, however, are less predictive than the well-known exponentiation of the ln^k N terms.
[ { "created": "Wed, 20 Jan 2010 14:09:26 GMT", "version": "v1" } ]
2010-01-21
[ [ "Vogt", "A.", "", "Liverpool Univ." ], [ "Moch", "S.", "", "DESY, Zeuthen" ], [ "Soar", "G.", "", "Liverpool\n Univ." ], [ "Vermaseren", "J. A. M.", "", "NIKHEF, Amsterdam" ] ]
We have studied the physical evolution kernels for nine non-singlet observables in deep-inelastic scattering (DIS), semi-inclusive e^+e^-annihilation and the Drell-Yan (DY) process, and for the flavour-singlet case of the photon- and heavy-top Higgs-exchange structure functions (F_2, F_phi) in DIS. All known contributions to these kernels show an only single-logarithmic large-x enhancement at all powers of 1-x. Conjecturing that this behaviour persists to (all) higher orders, we have predicted the highest three (DY: two) double logarithms of the higher-order non-singlet coefficient functions and of the four-loop singlet splitting functions. The coefficient-function predictions canbe written as exponentiations of 1/N-suppressed contributions in Mellin-N space which, however, are less predictive than the well-known exponentiation of the ln^k N terms.
0903.1794
Gilad Perez
Alexander L. Kagan, Gilad Perez, Tomer Volansky and Jure Zupan
General Minimal Flavor Violation
5 pages and no figures
Phys.Rev.D80:076002,2009
10.1103/PhysRevD.80.076002
WIS/03/09-MARCH-DPP
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
A model independent study of the minimal flavor violation (MFV) framework is presented, where the only sources of flavor breaking at low energy are the up and down Yukawa matrices. Two limits are identified for the Yukawa coupling expansion: linear MFV, where it is truncated at the leading terms, and nonlinear MFV, where such a truncation is not possible due to large third generation Yukawa couplings. These are then resummed to all orders using non-linear sigma-model techniques familiar from models of collective breaking. Generically, flavor diagonal CP violating (CPV) sources in the UV can induce O(1) CPV in processes involving third generation quarks. Due to a residual U(2) symmetry, the extra CPV in B_d-\bar B_d mixing is bounded by CPV in B_s-\bar B_s mixing. If operators with right-handed light quarks are subdominant, the extra CPV is equal in the two systems, and is negligible in processes involving only the first two generations. We find large enhancements in the up type sector, both in CPV in D-\bar D mixing and in top flavor violation.
[ { "created": "Tue, 10 Mar 2009 15:17:08 GMT", "version": "v1" } ]
2009-10-29
[ [ "Kagan", "Alexander L.", "" ], [ "Perez", "Gilad", "" ], [ "Volansky", "Tomer", "" ], [ "Zupan", "Jure", "" ] ]
A model independent study of the minimal flavor violation (MFV) framework is presented, where the only sources of flavor breaking at low energy are the up and down Yukawa matrices. Two limits are identified for the Yukawa coupling expansion: linear MFV, where it is truncated at the leading terms, and nonlinear MFV, where such a truncation is not possible due to large third generation Yukawa couplings. These are then resummed to all orders using non-linear sigma-model techniques familiar from models of collective breaking. Generically, flavor diagonal CP violating (CPV) sources in the UV can induce O(1) CPV in processes involving third generation quarks. Due to a residual U(2) symmetry, the extra CPV in B_d-\bar B_d mixing is bounded by CPV in B_s-\bar B_s mixing. If operators with right-handed light quarks are subdominant, the extra CPV is equal in the two systems, and is negligible in processes involving only the first two generations. We find large enhancements in the up type sector, both in CPV in D-\bar D mixing and in top flavor violation.
hep-ph/0207139
Luis Anchordoqui
Luis A. Anchordoqui, Jonathan L. Feng, Haim Goldberg, Alfred D. Shapere
Neutrino Bounds on Astrophysical Sources and New Physics
18 pages, 5 figures, added new figure comparing cosmic ray and LHC black hole rates, to be published in Phys. Rev. D
Phys.Rev.D66:103002,2002
10.1103/PhysRevD.66.103002
NUB-3229-Th-02, UCI-TR-2002-22, UK/02-09
hep-ph astro-ph hep-ex
null
Ultra-high energy cosmic neutrinos are incisive probes of both astrophysical sources and new TeV-scale physics. Such neutrinos would create extensive air showers deep in the atmosphere. The absence of such showers implies upper limits on incoming neutrino fluxes and cross sections. Combining the exposures of AGASA, the largest existing ground array, with the exposure of the Fly's Eye fluorescence detector integrated over all its operating epochs, we derive 95% CL bounds that substantially improve existing limits. We begin with model-independent bounds on astrophysical fluxes, assuming standard model cross sections, and model-independent bounds on new physics cross sections, assuming a conservative cosmogenic flux. We then derive model-dependent constraints on new components of neutrino flux for several assumed power spectra, and we update bounds on the fundamental Planck scale M_D in extra dimension scenarios from black hole production. For large numbers of extra dimensions, we find M_D > 2.0 (1.1) TeV for \mbhmin = M_D (5 M_D), comparable to or exceeding the most stringent constraints to date.
[ { "created": "Thu, 11 Jul 2002 17:38:47 GMT", "version": "v1" }, { "created": "Fri, 27 Sep 2002 12:00:57 GMT", "version": "v2" } ]
2008-11-26
[ [ "Anchordoqui", "Luis A.", "" ], [ "Feng", "Jonathan L.", "" ], [ "Goldberg", "Haim", "" ], [ "Shapere", "Alfred D.", "" ] ]
Ultra-high energy cosmic neutrinos are incisive probes of both astrophysical sources and new TeV-scale physics. Such neutrinos would create extensive air showers deep in the atmosphere. The absence of such showers implies upper limits on incoming neutrino fluxes and cross sections. Combining the exposures of AGASA, the largest existing ground array, with the exposure of the Fly's Eye fluorescence detector integrated over all its operating epochs, we derive 95% CL bounds that substantially improve existing limits. We begin with model-independent bounds on astrophysical fluxes, assuming standard model cross sections, and model-independent bounds on new physics cross sections, assuming a conservative cosmogenic flux. We then derive model-dependent constraints on new components of neutrino flux for several assumed power spectra, and we update bounds on the fundamental Planck scale M_D in extra dimension scenarios from black hole production. For large numbers of extra dimensions, we find M_D > 2.0 (1.1) TeV for \mbhmin = M_D (5 M_D), comparable to or exceeding the most stringent constraints to date.
hep-ph/0308206
Carlo Giunti
Carlo Giunti
Double Beta Decay and the Absolute Neutrino Mass Scale
6 pages, Proceedings of NuFact 03, 5th International Workshop on Neutrino Factories & Superbeams, 5-11 June 2003, Columbia University, New York
null
10.1063/1.1818390
null
hep-ph astro-ph hep-ex
null
After a short review of the current status of three-neutrino mixing, the implications for the values of neutrino masses are discussed. The bounds on the absolute scale of neutrino masses from Tritium beta-decay and cosmological data are reviewed. Finally, we discuss the implications of three-neutrino mixing for neutrinoless double-beta decay.
[ { "created": "Wed, 20 Aug 2003 13:38:50 GMT", "version": "v1" } ]
2009-11-10
[ [ "Giunti", "Carlo", "" ] ]
After a short review of the current status of three-neutrino mixing, the implications for the values of neutrino masses are discussed. The bounds on the absolute scale of neutrino masses from Tritium beta-decay and cosmological data are reviewed. Finally, we discuss the implications of three-neutrino mixing for neutrinoless double-beta decay.
hep-ph/0401068
Igor Marfin
I. Marfin, V. Mossolov, T. Shishkina
Contribution of the main radiative corrections to anomalous quartic constants in process gamma-gamma-->WW
9 pages, 7 figures, talk given at Int. School-Seminar "The actual Problems of Microworld Physics", Gomel, 2003
null
null
null
hep-ph
null
Evaluation of anomalous couplings in the $\gamma\gamma\to W^+W^-$ process needs to calculate the cross section $\sigma(W^+W^-)$ with a high precision. Therefore one has to consider the main contribution of high order effects. In this paper contributions of anomalous quartic boson interaction given by ${\cal L}_0$, ${\cal L}_c$, $\tilde{{\cal L}}_0$ are analyzed in high-energy region. Influence of high order effects is studed in dependences of $\sigma(W^+W^-)$ on anomalous constants and contour plots with statistical error $2\delta$.
[ { "created": "Sun, 11 Jan 2004 12:41:47 GMT", "version": "v1" } ]
2007-05-23
[ [ "Marfin", "I.", "" ], [ "Mossolov", "V.", "" ], [ "Shishkina", "T.", "" ] ]
Evaluation of anomalous couplings in the $\gamma\gamma\to W^+W^-$ process needs to calculate the cross section $\sigma(W^+W^-)$ with a high precision. Therefore one has to consider the main contribution of high order effects. In this paper contributions of anomalous quartic boson interaction given by ${\cal L}_0$, ${\cal L}_c$, $\tilde{{\cal L}}_0$ are analyzed in high-energy region. Influence of high order effects is studed in dependences of $\sigma(W^+W^-)$ on anomalous constants and contour plots with statistical error $2\delta$.
hep-ph/0002300
Elena Gonzalez Ferreiro
A. Capella, E. G. Ferreiro and A. B. Kaidalov
Non-saturation of the J/psi suppression at large transverse energy in the comovers approach
12 pages, latex, 2 postscript figures
Phys.Rev.Lett. 85 (2000) 2080-2083
10.1103/PhysRevLett.85.2080
LPTHE Orsay 00-21
hep-ph
null
We show that, contrary to recent claims, the $J/\psi$ suppression resulting from its interaction with comovers does not saturate at large transverse energy $E_T$. On the contrary, it shows a characteristic structure - change of curvature near the knee of the $E_T$ distribution - which is due to the $E_T$ (or multiplicity) fluctuation, and agrees with recent experimental results.
[ { "created": "Tue, 29 Feb 2000 15:02:48 GMT", "version": "v1" } ]
2009-10-31
[ [ "Capella", "A.", "" ], [ "Ferreiro", "E. G.", "" ], [ "Kaidalov", "A. B.", "" ] ]
We show that, contrary to recent claims, the $J/\psi$ suppression resulting from its interaction with comovers does not saturate at large transverse energy $E_T$. On the contrary, it shows a characteristic structure - change of curvature near the knee of the $E_T$ distribution - which is due to the $E_T$ (or multiplicity) fluctuation, and agrees with recent experimental results.
2401.04948
Georgii Shestakov
N. N. Achasov and G. N. Shestakov
Toward an estimate of the amplitude $X(3872)\to\pi^0\chi_{c1}(1P)$
12 pages, 7 figures, v2, published version, clarifications and references added
Phys. Rev. D 109, 036028 (2024)
null
null
hep-ph hep-ex nucl-th
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
The well-known model of the triangle diagrams with $D^*\bar DD^*$ and $\bar D^*D\bar D^*$ mesons in the loops is compared with the modern data on the amplitude of the $X(3872)\to\pi^0\chi_{c1}(1P)$ decay. Considering the $X(3872)$ object as a $\chi_{c1}(2P)$ charmonium state, we introduce a parameter $\xi$ characterizing the scale of the isotopic symmetry violation in this decay and find a lower limit of $\xi\simeq0.0916$. The model incorporates the only fitted parameter associated with the form factor. We analyze in detail the influence of the form factor on the amplitude $X(3872)\to\pi^0 \chi_{c1}(1P)$ and on the parameter $\xi$. As the suppression of the amplitude by the form factor increases, $\xi$ increases. Due to the fact that the $X(3872)$ resonance is located practically at the threshold of the $D^0\bar D^{*0}$ channel, the amplitude of $X(3872) \to\pi^0\chi_{c1}(1P)$ turns out to be proportional to $\sqrt{m_d -m_u}$. Using the estimating values for the coupling constants $g_{XD\bar D^*}$, $g_{\chi_{ c1}D\bar D^*}$, and $g_{D^{*0}D^{*0}\pi^0}$, we show that the model of the triangle loop diagrams is in reasonable agreement with the available data. Apart from the difference in the masses of neutral and charged charmed mesons, any additional exotic sources of isospin violation in $X(3872)\to\pi^0\chi_{c1}(1P)$ (such as a significant difference between the coupling constants $g_{XD^0\bar D^{*0}}$ and $g_{XD^+ D^{*-}}$) are not required to interpret the data. This indirectly confirms the isotopic neutrality of the $X(3872)$, which is naturally realized for the $c\bar c$ state $\chi_{c1}(2P)$.
[ { "created": "Wed, 10 Jan 2024 06:06:43 GMT", "version": "v1" }, { "created": "Tue, 27 Feb 2024 04:13:14 GMT", "version": "v2" } ]
2024-02-28
[ [ "Achasov", "N. N.", "" ], [ "Shestakov", "G. N.", "" ] ]
The well-known model of the triangle diagrams with $D^*\bar DD^*$ and $\bar D^*D\bar D^*$ mesons in the loops is compared with the modern data on the amplitude of the $X(3872)\to\pi^0\chi_{c1}(1P)$ decay. Considering the $X(3872)$ object as a $\chi_{c1}(2P)$ charmonium state, we introduce a parameter $\xi$ characterizing the scale of the isotopic symmetry violation in this decay and find a lower limit of $\xi\simeq0.0916$. The model incorporates the only fitted parameter associated with the form factor. We analyze in detail the influence of the form factor on the amplitude $X(3872)\to\pi^0 \chi_{c1}(1P)$ and on the parameter $\xi$. As the suppression of the amplitude by the form factor increases, $\xi$ increases. Due to the fact that the $X(3872)$ resonance is located practically at the threshold of the $D^0\bar D^{*0}$ channel, the amplitude of $X(3872) \to\pi^0\chi_{c1}(1P)$ turns out to be proportional to $\sqrt{m_d -m_u}$. Using the estimating values for the coupling constants $g_{XD\bar D^*}$, $g_{\chi_{ c1}D\bar D^*}$, and $g_{D^{*0}D^{*0}\pi^0}$, we show that the model of the triangle loop diagrams is in reasonable agreement with the available data. Apart from the difference in the masses of neutral and charged charmed mesons, any additional exotic sources of isospin violation in $X(3872)\to\pi^0\chi_{c1}(1P)$ (such as a significant difference between the coupling constants $g_{XD^0\bar D^{*0}}$ and $g_{XD^+ D^{*-}}$) are not required to interpret the data. This indirectly confirms the isotopic neutrality of the $X(3872)$, which is naturally realized for the $c\bar c$ state $\chi_{c1}(2P)$.
2109.07597
Yunhua Ding
Yunhua Ding, Teague D. Olewiler, and Mohammad Farhan Rawnak
Penning-Trap Searches for Lorentz and CPT Violation
20 pages, accepted for publication in Symmetry
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
An overview of recent progress on testing Lorentz and CPT symmetry using Penning traps is presented. The theory of quantum electrodynamics with Lorentz-violating operators of mass dimensions up to six is summarized. Dominant shifts in the cyclotron and anomaly frequencies of the confined particles and antiparticles due to Lorentz and CPT violation are derived. Existing results of the comparisons of charge-to-mass ratios and magnetic moments involving protons, antiprotons, electrons, and positrons are used to constrain various coefficients for Lorentz violation.
[ { "created": "Wed, 15 Sep 2021 22:17:07 GMT", "version": "v1" } ]
2021-09-17
[ [ "Ding", "Yunhua", "" ], [ "Olewiler", "Teague D.", "" ], [ "Rawnak", "Mohammad Farhan", "" ] ]
An overview of recent progress on testing Lorentz and CPT symmetry using Penning traps is presented. The theory of quantum electrodynamics with Lorentz-violating operators of mass dimensions up to six is summarized. Dominant shifts in the cyclotron and anomaly frequencies of the confined particles and antiparticles due to Lorentz and CPT violation are derived. Existing results of the comparisons of charge-to-mass ratios and magnetic moments involving protons, antiprotons, electrons, and positrons are used to constrain various coefficients for Lorentz violation.
hep-ph/9805387
Carlo Giunti
S.M. Bilenky, C. Giunti, W. Grimus
Four-neutrino mixing and long-baseline neutrino oscillation experiments
5 pages, including 2 figures. Talk presented by C. Giunti at the XXXIIInd Rencontres de Moriond: Electroweak Interactions and Unified Theories, Les Arcs 1800 (France), March 14-21 1998
null
null
DFTT 24/98, UWThPh-1998-23
hep-ph
null
We consider the two schemes with four massive neutrinos which are compatible with the results of all neutrino oscillation experiments. We show that in these two schemes the probabilities of nu_e disappearance and nu_mu->nu_e appearance in long-baseline experiments are strongly suppressed.
[ { "created": "Wed, 20 May 1998 09:37:35 GMT", "version": "v1" } ]
2007-05-23
[ [ "Bilenky", "S. M.", "" ], [ "Giunti", "C.", "" ], [ "Grimus", "W.", "" ] ]
We consider the two schemes with four massive neutrinos which are compatible with the results of all neutrino oscillation experiments. We show that in these two schemes the probabilities of nu_e disappearance and nu_mu->nu_e appearance in long-baseline experiments are strongly suppressed.
hep-ph/0702281
R. Sekhar Chivukula
R. Sekhar Chivukula, Neil D. Christensen, Baradhwaj Coleppa, and Elizabeth H. Simmons
Unitarity and Bounds on the Scale of Fermion Mass Generation
12 pages, 11 eps figures included, revtex. Refrences added; wording modified slightly to emphasize focus on top-quark
Phys.Rev.D75:073018,2007
10.1103/PhysRevD.75.073018
MSUHEP-070227
hep-ph hep-lat hep-th
null
The scale of fermion mass generation can, as shown by Appelquist and Chanowitz, be bounded from above by relating it to the scale of unitarity violation in the helicity nonconserving amplitude for fermion-anti-fermion pairs to scatter into pairs of longitudinally polarized electroweak gauge bosons. In this paper, we examine the process t tbar -> W_L W_L in a family of phenomenologically-viable deconstructed Higgsless models and we show that scale of unitarity violation depends on the mass of the additional vector-like fermion states that occur in these theories (the states that are the deconstructed analogs of Kaluza-Klein partners of the ordinary fermions in a five-dimensional theory). For sufficiently light vector fermions, and for a deconstructed theory with sufficiently many lattice sites (that is, sufficiently close to the continuum limit), the Appelquist-Chanowitz bound can be substantially weakened. More precisely, we find that, as one varies the mass of the vector-like fermion for fixed top-quark and gauge-boson masses, the bound on the scale of top-quark mass generation interpolates smoothly between the Appelquist-Chanowitz bound and one that can, potentially, be much higher. In these theories, therefore, the bound on the scale of fermion mass generation is independent of the bound on the scale of gauge-boson mass generation. While our analysis focuses on deconstructed Higgsless models, any theory in which top-quark mass generation proceeds via the mixing of chiral and vector fermions will give similar results.
[ { "created": "Tue, 27 Feb 2007 18:50:15 GMT", "version": "v1" }, { "created": "Thu, 1 Mar 2007 17:55:28 GMT", "version": "v2" } ]
2008-11-26
[ [ "Chivukula", "R. Sekhar", "" ], [ "Christensen", "Neil D.", "" ], [ "Coleppa", "Baradhwaj", "" ], [ "Simmons", "Elizabeth H.", "" ] ]
The scale of fermion mass generation can, as shown by Appelquist and Chanowitz, be bounded from above by relating it to the scale of unitarity violation in the helicity nonconserving amplitude for fermion-anti-fermion pairs to scatter into pairs of longitudinally polarized electroweak gauge bosons. In this paper, we examine the process t tbar -> W_L W_L in a family of phenomenologically-viable deconstructed Higgsless models and we show that scale of unitarity violation depends on the mass of the additional vector-like fermion states that occur in these theories (the states that are the deconstructed analogs of Kaluza-Klein partners of the ordinary fermions in a five-dimensional theory). For sufficiently light vector fermions, and for a deconstructed theory with sufficiently many lattice sites (that is, sufficiently close to the continuum limit), the Appelquist-Chanowitz bound can be substantially weakened. More precisely, we find that, as one varies the mass of the vector-like fermion for fixed top-quark and gauge-boson masses, the bound on the scale of top-quark mass generation interpolates smoothly between the Appelquist-Chanowitz bound and one that can, potentially, be much higher. In these theories, therefore, the bound on the scale of fermion mass generation is independent of the bound on the scale of gauge-boson mass generation. While our analysis focuses on deconstructed Higgsless models, any theory in which top-quark mass generation proceeds via the mixing of chiral and vector fermions will give similar results.
2105.05665
Fayyazuddin Fayyazuddin
Fayyazuddin
W-exchange contributions in hadronic decays of bottom baryon $\Lambda_{b}$
null
null
null
null
hep-ph hep-ex
http://creativecommons.org/licenses/by/4.0/
The nonleptonic decays $\Lambda_{b}\rightarrow\Sigma_{c}^{*-}\pi^{+},\Xi_{c}^{*0}K^{0}$ and $\Lambda_{b}\rightarrow\Delta^{0}D^{0},\Sigma^{*-}D_{0}^{+}$ are studied. In addition, the decays $\Lambda_{b}\rightarrow\Xi_{c}^{0}K^{0},\Sigma^{-}D_{s}^{+}$ are analyzed. For all these decays the dominant contribution comes from $W-$exchange, and for the decay $\Lambda_{b}\rightarrow\Lambda_{c}^{+}\pi^{-}$, in addition to factorization, baryon pole contribution to the $p$-wave (parity conserving) decay amplitude $B$ is discussed.
[ { "created": "Wed, 12 May 2021 13:55:40 GMT", "version": "v1" } ]
2021-05-13
[ [ "Fayyazuddin", "", "" ] ]
The nonleptonic decays $\Lambda_{b}\rightarrow\Sigma_{c}^{*-}\pi^{+},\Xi_{c}^{*0}K^{0}$ and $\Lambda_{b}\rightarrow\Delta^{0}D^{0},\Sigma^{*-}D_{0}^{+}$ are studied. In addition, the decays $\Lambda_{b}\rightarrow\Xi_{c}^{0}K^{0},\Sigma^{-}D_{s}^{+}$ are analyzed. For all these decays the dominant contribution comes from $W-$exchange, and for the decay $\Lambda_{b}\rightarrow\Lambda_{c}^{+}\pi^{-}$, in addition to factorization, baryon pole contribution to the $p$-wave (parity conserving) decay amplitude $B$ is discussed.
1303.3521
Chunhui Chen
Chunhui Chen
Identifying boosted hadronically decaying top quark using jet substructure in its center-of-mass frame
6 pages, 6 figures. Published in Phys. Rev. D 87, 074007 (2013). arXiv admin note: text overlap with arXiv:1112.2567
Phys. Rev. D 87, 074007 (2013)
10.1103/PhysRevD.87.074007
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In this paper we study the identification of boosted hadronically decaying top quarks using jet substructure in the center-of-mass frame of the jet. We demonstrate that the method can greatly reduce the QCD jet background while maintaining high identification efficiency of the boosted top quark even in a very high pileup condition. Applications to searches for heavy resonances that decay to a $t\bar{t}$ final state are also discussed.
[ { "created": "Thu, 14 Mar 2013 17:35:46 GMT", "version": "v1" }, { "created": "Wed, 10 Apr 2013 18:31:41 GMT", "version": "v2" } ]
2013-04-11
[ [ "Chen", "Chunhui", "" ] ]
In this paper we study the identification of boosted hadronically decaying top quarks using jet substructure in the center-of-mass frame of the jet. We demonstrate that the method can greatly reduce the QCD jet background while maintaining high identification efficiency of the boosted top quark even in a very high pileup condition. Applications to searches for heavy resonances that decay to a $t\bar{t}$ final state are also discussed.
2209.01222
Jernej Kamenik
Darius A. Faroughy, Jernej F. Kamenik, Manuel Szewc and Jure Zupan
Accessing CKM suppressed top decays at the LHC
19 pages, 7 figures
SciPost Phys. 16, 131 (2024)
10.21468/SciPostPhys.16.5.131
null
hep-ph hep-ex
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We propose an extension of the existing experimental strategy for measuring branching fractions of top quark decays, targeting specifically $t\to j_q W$, where $j_q$ is a light quark jet. The improved strategy uses orthogonal $b$- and $q$-taggers, and adds a new observable, the number of light-quark-tagged jets, to the already commonly used observable, the fraction of $b$-tagged jets in an event. Careful inclusion of the additional complementary observable significantly increases the expected statistical power of the analysis, with the possibility of excluding $|V_{tb}|=1$ at $95\%$ C.L. at the HL-LHC, and accessing directly the standard model value of $|V_{td}|^2+|V_{ts}|^2$.
[ { "created": "Fri, 2 Sep 2022 18:00:02 GMT", "version": "v1" } ]
2024-05-29
[ [ "Faroughy", "Darius A.", "" ], [ "Kamenik", "Jernej F.", "" ], [ "Szewc", "Manuel", "" ], [ "Zupan", "Jure", "" ] ]
We propose an extension of the existing experimental strategy for measuring branching fractions of top quark decays, targeting specifically $t\to j_q W$, where $j_q$ is a light quark jet. The improved strategy uses orthogonal $b$- and $q$-taggers, and adds a new observable, the number of light-quark-tagged jets, to the already commonly used observable, the fraction of $b$-tagged jets in an event. Careful inclusion of the additional complementary observable significantly increases the expected statistical power of the analysis, with the possibility of excluding $|V_{tb}|=1$ at $95\%$ C.L. at the HL-LHC, and accessing directly the standard model value of $|V_{td}|^2+|V_{ts}|^2$.
1804.07241
Madhurima Pandey
Madhurima Pandey
Unparticle Decay of Neutrinos and its Possible Signatures at a ${\rm Km}^2$ Detector for (3+1) Flavour Framework
20 pages LaTeX, 5 eps figures
null
10.1007/JHEP01(2019)066
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider a scenario where ultra high energy neutrinos undergo unparticle decay during its passage from its cosmological source to Earth. The idea of unparticle had been first proposed by Georgi by considering the possible existence of an unknown scale invariant sector at high energies and the unparticles in this sector manifest itself below a dimensional transmutation scale $\Lambda_{\cal U}$. We then explore the possible signature of such decaying neutrinos to unparticles at a square kilometer detector such as IceCube.
[ { "created": "Thu, 19 Apr 2018 15:48:29 GMT", "version": "v1" } ]
2019-01-30
[ [ "Pandey", "Madhurima", "" ] ]
We consider a scenario where ultra high energy neutrinos undergo unparticle decay during its passage from its cosmological source to Earth. The idea of unparticle had been first proposed by Georgi by considering the possible existence of an unknown scale invariant sector at high energies and the unparticles in this sector manifest itself below a dimensional transmutation scale $\Lambda_{\cal U}$. We then explore the possible signature of such decaying neutrinos to unparticles at a square kilometer detector such as IceCube.
1907.01472
Samoil Bilenky M.
S. Bilenky
Neutrino Masses from the Point of View of Economy and Simplicity
null
null
null
null
hep-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
In the framework of such basic principles as local gauge invariance, unification of the weak and electromagnetic interactions and spontaneous symmetry breaking in the Standard Model the most economical and simplest possibilities are realized. We discuss the problem of neutrino masses from the point of view of economy and simplicity. It is unlikely that neutrino masses are of the same SM origin as masses of leptons and quarks. The Weinberg effective Lagrangian is the simplest and the most economical, beyond the Standard Model mechanism of the generation of small Majorana neutrino masses. The resolution of the sterile neutrino anomaly and observation of the neutrinoless double $\beta$-decay would be crucial tests of this mechanism.
[ { "created": "Tue, 2 Jul 2019 16:02:35 GMT", "version": "v1" }, { "created": "Tue, 9 Jul 2019 04:58:41 GMT", "version": "v2" } ]
2019-07-10
[ [ "Bilenky", "S.", "" ] ]
In the framework of such basic principles as local gauge invariance, unification of the weak and electromagnetic interactions and spontaneous symmetry breaking in the Standard Model the most economical and simplest possibilities are realized. We discuss the problem of neutrino masses from the point of view of economy and simplicity. It is unlikely that neutrino masses are of the same SM origin as masses of leptons and quarks. The Weinberg effective Lagrangian is the simplest and the most economical, beyond the Standard Model mechanism of the generation of small Majorana neutrino masses. The resolution of the sterile neutrino anomaly and observation of the neutrinoless double $\beta$-decay would be crucial tests of this mechanism.
2304.04924
Igor Strakovsky
Igor Strakovsky (GWU), William J. Briscoe (GWU), Eugene Chudakov (JLab), Ilya Larin (UMASS Amherst), Lubomir Pentchev (JLab), Axel Schmidt (GWU), and Ronald L. Workman (GWU)
Is the LHCb $P_c(4312)^+$ plausible in the GlueX $\gamma p\to J/\psi p$ total cross sections ?
4 pages, 3 figures, 2 tables
null
null
null
hep-ph hep-ex nucl-ex nucl-th
http://creativecommons.org/licenses/by/4.0/
New high-statistics total cross section data for $\gamma p\to J/\psi p$ from the GLUonic EXcitation (GlueX) experiment are fitted in a search for the exotic $P_c(4312)^+$ state observed by the Large Hadron Collider beauty (LHCb) collaboration. The integrated luminosity of this GlueX experiment was about $320~\mathrm{pb^{-1}}$. The fits show that destructive interference involving an $S$-wave resonance and associated non-resonance background produces a sharp dip structure about $75~\mathrm{MeV}$ below the LHCb mass, in the same location as a similar structure is seen in the data. Limitations of the employed model and the need for improved statistics are discussed.
[ { "created": "Tue, 11 Apr 2023 01:30:39 GMT", "version": "v1" } ]
2023-04-12
[ [ "Strakovsky", "Igor", "", "GWU" ], [ "Briscoe", "William J.", "", "GWU" ], [ "Chudakov", "Eugene", "", "JLab" ], [ "Larin", "Ilya", "", "UMASS Amherst" ], [ "Pentchev", "Lubomir", "", "JLab" ], [ "Schmidt", ...
New high-statistics total cross section data for $\gamma p\to J/\psi p$ from the GLUonic EXcitation (GlueX) experiment are fitted in a search for the exotic $P_c(4312)^+$ state observed by the Large Hadron Collider beauty (LHCb) collaboration. The integrated luminosity of this GlueX experiment was about $320~\mathrm{pb^{-1}}$. The fits show that destructive interference involving an $S$-wave resonance and associated non-resonance background produces a sharp dip structure about $75~\mathrm{MeV}$ below the LHCb mass, in the same location as a similar structure is seen in the data. Limitations of the employed model and the need for improved statistics are discussed.
1805.06482
Maxim Bezuglov
M.A. Bezuglov and A.I. Onishchenko
Two-loop corrections to false vacuum decay in scalar field theory
20 pages, 3 figures, clarifications added
Physics Letters B Volume 788, 10 January 2019, Pages 122-130
10.1016/j.physletb.2018.11.005
null
hep-ph hep-th quant-ph
http://arxiv.org/licenses/nonexclusive-distrib/1.0/
We consider radiative corrections to false vacuum decay in a four-dimensional scalar field theory with cubic and quartic potential. Using planar thin wall approximation we were able to get analytical expression for the decay rate up to two loop order. The results obtained employ dimensional regularization and $\overline{MS}$ renormalization scheme.
[ { "created": "Wed, 16 May 2018 18:32:35 GMT", "version": "v1" }, { "created": "Tue, 29 May 2018 15:04:07 GMT", "version": "v2" }, { "created": "Sat, 24 Nov 2018 13:42:19 GMT", "version": "v3" } ]
2019-03-28
[ [ "Bezuglov", "M. A.", "" ], [ "Onishchenko", "A. I.", "" ] ]
We consider radiative corrections to false vacuum decay in a four-dimensional scalar field theory with cubic and quartic potential. Using planar thin wall approximation we were able to get analytical expression for the decay rate up to two loop order. The results obtained employ dimensional regularization and $\overline{MS}$ renormalization scheme.
hep-ph/0006099
null
N. Okamura (Theory Group, KEK), M. Tanimoto (Niigata Univ.)
Generic Relations of Flavor Mixings between Leptons and Quarks in SU(5)
16 pages, 2 figures, Some discussions are modified, but results are not changed
Prog.Theor.Phys. 105 (2001) 459-469
10.1143/PTP.105.459
KEK-TH-700, NIIG-DP-00-04
hep-ph
null
We have studied implications of the generic lopsided mass matrix of the charged leptons by taking the SU(5) GUT relation in the nearest-neighbor interaction (NNI) basis. We have found four interesting relations among the lepton mixings and the quark ones, which are independent of details of the model. These relations are discussed by using the experimental data. We have also discussed the relation between U_{e2} and U_{e3} incuding the contribution from the neutrino mass matrix. We have presented the probable value U_{e3}=0.05 \sim 0.16, which is independent of the solar neutrino solutions. The CP violating quantity J_{CP} is also discussed.
[ { "created": "Sat, 10 Jun 2000 07:29:03 GMT", "version": "v1" }, { "created": "Tue, 3 Oct 2000 05:48:09 GMT", "version": "v2" }, { "created": "Sat, 23 Dec 2000 06:33:25 GMT", "version": "v3" } ]
2009-10-31
[ [ "Okamura", "N.", "", "Theory Group, KEK" ], [ "Tanimoto", "M.", "", "Niigata Univ." ] ]
We have studied implications of the generic lopsided mass matrix of the charged leptons by taking the SU(5) GUT relation in the nearest-neighbor interaction (NNI) basis. We have found four interesting relations among the lepton mixings and the quark ones, which are independent of details of the model. These relations are discussed by using the experimental data. We have also discussed the relation between U_{e2} and U_{e3} incuding the contribution from the neutrino mass matrix. We have presented the probable value U_{e3}=0.05 \sim 0.16, which is independent of the solar neutrino solutions. The CP violating quantity J_{CP} is also discussed.
hep-ph/9309264
Papadopoulos
N.G.Antoniou, F.K.Diakonos, I.S.Mistakidis and C.G.Papadopoulos
Criticality, Fractality and Intermittency in Strong Interactions
15 pages + 2 figures (available on request), CERN-TH.6990/93, UA/NPPS-5-93
Phys.Rev. D49 (1994) 5789-5797
10.1103/PhysRevD.49.5789
null
hep-ph
null
Assuming a second-order phase transition for the hadronization process, we attempt to associate intermittency patterns in high-energy hadronic collisions to fractal structures in configuration space and corresponding intermittency indices to the isothermal critical exponent at the transition temperature. In this approach, the most general multidimensional intermittency pattern, associated to a second-order phase transition of the strongly interacting system, is determined, and its relevance to present and future experiments is discussed.
[ { "created": "Wed, 15 Sep 1993 10:38:56 GMT", "version": "v1" } ]
2009-10-22
[ [ "Antoniou", "N. G.", "" ], [ "Diakonos", "F. K.", "" ], [ "Mistakidis", "I. S.", "" ], [ "Papadopoulos", "C. G.", "" ] ]
Assuming a second-order phase transition for the hadronization process, we attempt to associate intermittency patterns in high-energy hadronic collisions to fractal structures in configuration space and corresponding intermittency indices to the isothermal critical exponent at the transition temperature. In this approach, the most general multidimensional intermittency pattern, associated to a second-order phase transition of the strongly interacting system, is determined, and its relevance to present and future experiments is discussed.
hep-ph/9706418
Christoph Hofmann
Christoph P. Hofmann
Effective Analysis of the O(N) Antiferromagnet: Low Temperature Expansion of the Order Parameter
Published version
Phys.Rev. B60 (1999) 406
10.1103/PhysRevB.60.406
BUTP-97/15
hep-ph cond-mat
null
We investigate the low energy properties of Lorentz-invariant theories with a spontaneously broken rotation symmetry O(N) $\to$ O(N--1). The leading coefficients of the low temperature expansion for the partition function are calculated up to and including three loops. Emphasis is put into the special case N=3: it describes the antiferromagnet which has been extensively studied. Our results obtained within the framework of the effective Lagrangian technique are compared with the literature. In particular, we show that, at order $T^7$ for the heat capacity and $T^6$ for the order parameter, respectively, logarithmic terms appear in the low temperature expansion, which have been overlooked so far.
[ { "created": "Thu, 19 Jun 1997 15:48:20 GMT", "version": "v1" }, { "created": "Tue, 26 May 1998 21:17:00 GMT", "version": "v2" }, { "created": "Sun, 19 Nov 2000 00:11:22 GMT", "version": "v3" } ]
2009-10-30
[ [ "Hofmann", "Christoph P.", "" ] ]
We investigate the low energy properties of Lorentz-invariant theories with a spontaneously broken rotation symmetry O(N) $\to$ O(N--1). The leading coefficients of the low temperature expansion for the partition function are calculated up to and including three loops. Emphasis is put into the special case N=3: it describes the antiferromagnet which has been extensively studied. Our results obtained within the framework of the effective Lagrangian technique are compared with the literature. In particular, we show that, at order $T^7$ for the heat capacity and $T^6$ for the order parameter, respectively, logarithmic terms appear in the low temperature expansion, which have been overlooked so far.