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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/9209279 | null | M. Gronau | Large Penguin effects in the CP Asymmetry of B0d ->pi+pi- | (14 pages, PHYZZX, 1 figure, available upon request), SLAC-PUB-5911 | Phys.Lett.B300:163-168,1993 | 10.1016/0370-2693(93)90765-A | null | hep-ph | null | Penguin effects in the CP asymmetries of $B^0_d\rightarrow \pi^+\pi^-$ ,
$\bd\rightarrow\rho^{\pm}\pi^{\mp}$ and $\bd\rightarrow a^{\pm}_1 \pi^{\mp}$
are studied as function of the CKM unitarity triangle $\alpha$. Despite a
fairly small penguin amplitude, it leads to quite sizable uncertainties in the
determination of $\sin(2\alpha)$ from all but very large asymmetries. This
effect is maximal for vanishing final state interaction phases, for which it
can cause, for instance, an asymmetry of 40\%\ if $\alpha=\pi/2$.
| [
{
"created": "Thu, 24 Sep 1992 21:48:00 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Gronau",
"M.",
""
]
] | Penguin effects in the CP asymmetries of $B^0_d\rightarrow \pi^+\pi^-$ , $\bd\rightarrow\rho^{\pm}\pi^{\mp}$ and $\bd\rightarrow a^{\pm}_1 \pi^{\mp}$ are studied as function of the CKM unitarity triangle $\alpha$. Despite a fairly small penguin amplitude, it leads to quite sizable uncertainties in the determination of $\sin(2\alpha)$ from all but very large asymmetries. This effect is maximal for vanishing final state interaction phases, for which it can cause, for instance, an asymmetry of 40\%\ if $\alpha=\pi/2$. |
hep-ph/9406418 | null | Oscar F. Hernandez and David London | Triangles, Triangles, Triangles: CP Violation in the B System and the
Measurement of Strong and Weak Phases | (Based on two talks presented at the
Montreal-Rochester-Syracuse-Toronto Conference, McGill University, May 1994,
and to appear in the proceedings published World Scientific.), 15 pages and 8
figures in one simple Postscript file, UdeM-LPN-TH-198 | null | null | null | hep-ph | null | We present the current wisdom regarding the measurement of the CP-violating
phases of the CKM unitarity triangle in $B$-meson decays. After an introduction
to the SM picture of CP violation, we review direct and indirect CP violation,
the role of penguins and isospin analysis, and $B\to DK$ decays. We also
discuss recent work on how to use SU(3) flavor symmetry, along with some
dynamical approximations, to get at the CKM weak phases. Through
time-independent $B$-decay measurements alone, we show that it is possible to
extract all information: the weak phases, the incalculable strong phase shifts,
and the sizes of the tree, color-suppressed, and penguin contributions to these
decays.
| [
{
"created": "Wed, 29 Jun 1994 03:16:52 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Hernandez",
"Oscar F.",
""
],
[
"London",
"David",
""
]
] | We present the current wisdom regarding the measurement of the CP-violating phases of the CKM unitarity triangle in $B$-meson decays. After an introduction to the SM picture of CP violation, we review direct and indirect CP violation, the role of penguins and isospin analysis, and $B\to DK$ decays. We also discuss recent work on how to use SU(3) flavor symmetry, along with some dynamical approximations, to get at the CKM weak phases. Through time-independent $B$-decay measurements alone, we show that it is possible to extract all information: the weak phases, the incalculable strong phase shifts, and the sizes of the tree, color-suppressed, and penguin contributions to these decays. |
hep-ph/0409168 | Robert L. Jaffe | Frank Wilczek | Diquarks as Inspiration and as Objects | 15 pages, 1 figure. Solicited contribution to the Ian Kogan memorial
volume, ed. M. Shifman. v2: several typos corrected | null | 10.1142/9789812775344_0007 | MIT-CTP-3529 | hep-ph nucl-th | null | It is plausible that several of the most profound aspects of low-energy QCD
dynamics are connected to diquark correlations, including: paucity of exotics
(which is the foundation of the quark model and of traditional nuclear
physics), similarity of mesons and baryons, color superconductivity at high
density, hyperfine splittings, $\Delta I = 1/2$ rule, and some striking
features of structure and fragmentation functions. After a brief overview of
these issues, I discuss how diquarks can be studied in isolation, both
phenomenologically and numerically, and present approximate mass differences
for diquarks with different quantum numbers. The mass-loaded generalization of
the Chew-Frautschi formula provides an essential tool.
| [
{
"created": "Tue, 14 Sep 2004 22:02:43 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Sep 2004 11:05:19 GMT",
"version": "v2"
}
] | 2016-11-23 | [
[
"Wilczek",
"Frank",
""
]
] | It is plausible that several of the most profound aspects of low-energy QCD dynamics are connected to diquark correlations, including: paucity of exotics (which is the foundation of the quark model and of traditional nuclear physics), similarity of mesons and baryons, color superconductivity at high density, hyperfine splittings, $\Delta I = 1/2$ rule, and some striking features of structure and fragmentation functions. After a brief overview of these issues, I discuss how diquarks can be studied in isolation, both phenomenologically and numerically, and present approximate mass differences for diquarks with different quantum numbers. The mass-loaded generalization of the Chew-Frautschi formula provides an essential tool. |
2306.00564 | Akira Watanabe | Zhibo Liu, Akira Watanabe | Elastic pion-proton and pion-pion scattering via the holographic Pomeron
and Reggeon exchange | 21 pages, 9 figures, typos corrected | null | 10.1103/PhysRevD.108.034010 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The elastic pion-proton and pion-pion scattering are studied in a holographic
QCD model, focusing on the Regge regime. Taking into account the Pomeron and
Reggeon exchange, which are described by the Reggeized $2^{++}$ glueball and
vector meson propagator respectively, the total and differential cross sections
are calculated. The adjustable parameters involved in the model are determined
with the experimental data of the pion-proton total cross sections. The
differential cross sections can be predicted without any additional parameters,
and it is shown that our predictions are consistent with the data. The energy
dependence of the Pomeron and Reggeon contribution is also discussed.
| [
{
"created": "Thu, 1 Jun 2023 11:25:26 GMT",
"version": "v1"
},
{
"created": "Mon, 31 Jul 2023 16:18:15 GMT",
"version": "v2"
},
{
"created": "Wed, 27 Mar 2024 13:09:05 GMT",
"version": "v3"
}
] | 2024-03-28 | [
[
"Liu",
"Zhibo",
""
],
[
"Watanabe",
"Akira",
""
]
] | The elastic pion-proton and pion-pion scattering are studied in a holographic QCD model, focusing on the Regge regime. Taking into account the Pomeron and Reggeon exchange, which are described by the Reggeized $2^{++}$ glueball and vector meson propagator respectively, the total and differential cross sections are calculated. The adjustable parameters involved in the model are determined with the experimental data of the pion-proton total cross sections. The differential cross sections can be predicted without any additional parameters, and it is shown that our predictions are consistent with the data. The energy dependence of the Pomeron and Reggeon contribution is also discussed. |
hep-ph/0610062 | Conrado Albertus-Torres | C. Albertus, J. M. Flynn, E. Hernandez, J. Nieves, J. M. Verde-Velasco | Study of the semileptonic decays B->pi, D->pi and D->K | 3 pages, 5 figures. Talk given at the IV International Conference on
Quarks and Nuclear Physics (QNP06), Madrid, June 5th - 10th 2006 | Eur.Phys.J.A31:725-727,2007 | 10.1140/epja/i2006-10247-9 | SHEP 0631 | hep-ph | null | The semileptonic decay B->pi is studied starting from a simple quark model
that takes into account the effect of the B* resonance. A novel, multiply
subtracted, Omnes dispersion relation has been implemented to extend the
predictions of the quark model to all q^2 values accesible in the physical
decay. By comparison to the experimental data, we extract |V_ub|=0.0034 +/-
0.0003(exp.) +/- 0.0007(theory). As a further test of the model, we have also
studied D->pi and D->K decays for which we get good agreement with experiment.
| [
{
"created": "Thu, 5 Oct 2006 13:34:36 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Albertus",
"C.",
""
],
[
"Flynn",
"J. M.",
""
],
[
"Hernandez",
"E.",
""
],
[
"Nieves",
"J.",
""
],
[
"Verde-Velasco",
"J. M.",
""
]
] | The semileptonic decay B->pi is studied starting from a simple quark model that takes into account the effect of the B* resonance. A novel, multiply subtracted, Omnes dispersion relation has been implemented to extend the predictions of the quark model to all q^2 values accesible in the physical decay. By comparison to the experimental data, we extract |V_ub|=0.0034 +/- 0.0003(exp.) +/- 0.0007(theory). As a further test of the model, we have also studied D->pi and D->K decays for which we get good agreement with experiment. |
0710.2578 | Stefano Scopel | Jae Sik Lee (Seoul Natl. U.), Stefano Scopel (Korea Inst. Advanced
Study, Seoul) | The Lightest Higgs Boson and Relic Neutralino in the MSSM with CP
Violation | Submitted for the SUSY07 proceedings, 4 pages, LaTeX, 2 figures | null | null | null | hep-ph | null | In a minimal supersymmetric extension of the standard model (MSSM) with
explicit CP violation a mass of the lightest Higgs boson H_1 in the range 7
GeV} < M_{H_1} < 10 GeV is experimentally allowed by present accelerator
limits. In the same scenario a lightest neutralino as light as 2.9 GeV can be a
viable dark matter candidate, provided that a departure from the usual GUT
relation among gaugino masses is assumed.
| [
{
"created": "Sat, 13 Oct 2007 03:28:57 GMT",
"version": "v1"
}
] | 2007-10-16 | [
[
"Lee",
"Jae Sik",
"",
"Seoul Natl. U."
],
[
"Scopel",
"Stefano",
"",
"Korea Inst. Advanced\n Study, Seoul"
]
] | In a minimal supersymmetric extension of the standard model (MSSM) with explicit CP violation a mass of the lightest Higgs boson H_1 in the range 7 GeV} < M_{H_1} < 10 GeV is experimentally allowed by present accelerator limits. In the same scenario a lightest neutralino as light as 2.9 GeV can be a viable dark matter candidate, provided that a departure from the usual GUT relation among gaugino masses is assumed. |
1501.07890 | Andrea Tesi | Matthew Low, Andrea Tesi, Lian-Tao Wang | The Twin Higgs mechanism and Composite Higgs | 28 pages, 4 figures, 3 tables; v2: added references and comments,
fixed typos, published in PRD | Phys. Rev. D 91, 095012 (2015) | 10.1103/PhysRevD.91.095012 | EFI-15-2 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We combine the Twin Higgs mechanism with the paradigm of Composite Higgs
models. In this class of models the Higgs is a pseudo-Nambu-Goldstone boson
from a strongly coupled sector near the TeV scale, and it is additionally
protected by a discrete symmetry due to the twin mechanism. We discuss the
model building issues associated with this setup and quantify the tuning needed
to achieve the correct electroweak vacuum and the Higgs mass. In contrast to
standard Composite Higgs models, the lightest resonance associated with the top
sector is the uncolored mirror top, while the colored top partners can be made
parameterically heavier without extra tuning. In some cases, the vector
resonances are predicted to lie in the multi-TeV range. We present models where
the resonances - both fermions and vectors - being heavier alleviates the
pressure on naturalness coming from direct searches demonstrating that theories
with low tuning may survive constraints from the Large Hadron Collider.
| [
{
"created": "Fri, 30 Jan 2015 19:52:29 GMT",
"version": "v1"
},
{
"created": "Fri, 22 May 2015 06:17:32 GMT",
"version": "v2"
}
] | 2015-05-25 | [
[
"Low",
"Matthew",
""
],
[
"Tesi",
"Andrea",
""
],
[
"Wang",
"Lian-Tao",
""
]
] | We combine the Twin Higgs mechanism with the paradigm of Composite Higgs models. In this class of models the Higgs is a pseudo-Nambu-Goldstone boson from a strongly coupled sector near the TeV scale, and it is additionally protected by a discrete symmetry due to the twin mechanism. We discuss the model building issues associated with this setup and quantify the tuning needed to achieve the correct electroweak vacuum and the Higgs mass. In contrast to standard Composite Higgs models, the lightest resonance associated with the top sector is the uncolored mirror top, while the colored top partners can be made parameterically heavier without extra tuning. In some cases, the vector resonances are predicted to lie in the multi-TeV range. We present models where the resonances - both fermions and vectors - being heavier alleviates the pressure on naturalness coming from direct searches demonstrating that theories with low tuning may survive constraints from the Large Hadron Collider. |
hep-ph/0302239 | Peter Watson | P. J. S. Watson | Bouncing Neutrons and the Neutron Centrifuge | 7 pages, 7 figures | J.Phys.G29:1451,2003 | 10.1088/0954-3899/29/7/311 | null | hep-ph | null | The recent observation of the quantum state of the neutron bouncing freely
under gravity allows some novel experiments. A method of purifying the ground
state is given, and possible applications to the measurement of the electric
dipole moment of the neutron and the short distance behaviour of gravity are
discussed.
| [
{
"created": "Wed, 26 Feb 2003 12:32:03 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Watson",
"P. J. S.",
""
]
] | The recent observation of the quantum state of the neutron bouncing freely under gravity allows some novel experiments. A method of purifying the ground state is given, and possible applications to the measurement of the electric dipole moment of the neutron and the short distance behaviour of gravity are discussed. |
2401.00848 | Javier M. Lizana | Bernat Capdevila, Andreas Crivellin, Javier M. Lizana, Stefan Pokorski | $SU(2)_L$ deconstruction and flavour (non)-universality | 14 pages + 8 appendices, 3 figures, version accepted for publication
in JHEP | null | null | ZU-TH 02/24, IFT-UAM/CSIC-23-162 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study two-site deconstructions of the $SU(2)_L$ gauge group factor of the
SM. Models based on this approach can explain the hierarchies of the quark
masses and CKM mixing between third and light families if these fields are
localised on different sites by the presence of hierarchical new physics
scales. The model leads to an accidental global $U(2)_q\times U(3)_u\times
U(3)_d$ flavour symmetry which prevents dangerously large effects in flavour
observables, making a TeV extension of the SM possible. Given the structure of
the PMNS matrix in the neutrino sector, we explore different possibilities for
the arrangement of the leptons on the two sites, and consider different models
with $U(2)_{\ell}$ or $U(3)_{\ell}$ flavour symmetries. The phenomenology of
the models is mostly governed by a massive vector triplet of $SU(2)_L$. We
study the interesting interplay between LHC searches and precision observables.
In particular, one of the models can give a sizeable lepton flavour universal
effect in the Wilson coefficient $C_9$ while naturally suppressing
contributions to $C_{10}$, as suggested by current $b\to s\ell^+\ell^-$ data,
predicting simultaneously a mild positive shift in the $W$ boson mass.
| [
{
"created": "Mon, 1 Jan 2024 18:57:44 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Feb 2024 16:44:38 GMT",
"version": "v2"
},
{
"created": "Fri, 9 Aug 2024 13:14:57 GMT",
"version": "v3"
}
] | 2024-08-12 | [
[
"Capdevila",
"Bernat",
""
],
[
"Crivellin",
"Andreas",
""
],
[
"Lizana",
"Javier M.",
""
],
[
"Pokorski",
"Stefan",
""
]
] | We study two-site deconstructions of the $SU(2)_L$ gauge group factor of the SM. Models based on this approach can explain the hierarchies of the quark masses and CKM mixing between third and light families if these fields are localised on different sites by the presence of hierarchical new physics scales. The model leads to an accidental global $U(2)_q\times U(3)_u\times U(3)_d$ flavour symmetry which prevents dangerously large effects in flavour observables, making a TeV extension of the SM possible. Given the structure of the PMNS matrix in the neutrino sector, we explore different possibilities for the arrangement of the leptons on the two sites, and consider different models with $U(2)_{\ell}$ or $U(3)_{\ell}$ flavour symmetries. The phenomenology of the models is mostly governed by a massive vector triplet of $SU(2)_L$. We study the interesting interplay between LHC searches and precision observables. In particular, one of the models can give a sizeable lepton flavour universal effect in the Wilson coefficient $C_9$ while naturally suppressing contributions to $C_{10}$, as suggested by current $b\to s\ell^+\ell^-$ data, predicting simultaneously a mild positive shift in the $W$ boson mass. |
hep-ph/0604149 | Michael Strickland | Adrian Dumitru, Yasushi Nara and Michael Strickland | Ultraviolet avalanche in anisotropic non-Abelian plasmas | 22 pages, 10 figures; v3: small textual changes; updated to
correspond with version to appear in publication | Phys.Rev.D75:025016,2007 | 10.1103/PhysRevD.75.025016 | null | hep-ph | null | We present solutions of coupled particle-field evolution in classical U(1)
and SU(2) gauge theories in real time on three-dimensional lattices. For
strongly anisotropic particle momentum distributions, we find qualitatively
different behavior for the two theories when the field strength is high enough
that non-Abelian self-interactions matter for SU(2). It appears that the energy
drained by a Weibel-like plasma instability from the particles does not build
up exponentially in transverse magnetic fields but instead returns,
isotropically, to the hard scale via a rapid avalanche into the ultraviolet.
| [
{
"created": "Tue, 18 Apr 2006 12:18:19 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jul 2006 14:00:53 GMT",
"version": "v2"
},
{
"created": "Fri, 12 Jan 2007 11:29:25 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Dumitru",
"Adrian",
""
],
[
"Nara",
"Yasushi",
""
],
[
"Strickland",
"Michael",
""
]
] | We present solutions of coupled particle-field evolution in classical U(1) and SU(2) gauge theories in real time on three-dimensional lattices. For strongly anisotropic particle momentum distributions, we find qualitatively different behavior for the two theories when the field strength is high enough that non-Abelian self-interactions matter for SU(2). It appears that the energy drained by a Weibel-like plasma instability from the particles does not build up exponentially in transverse magnetic fields but instead returns, isotropically, to the hard scale via a rapid avalanche into the ultraviolet. |
hep-ph/0701213 | Wan-Il Park | Wan-Il Park and Ewan D. Stewart | Couplings and spectra in modular inflation | 11 pages, format changed, some corrections of formulas | Phys.Rev.D77:023535,2008 | 10.1103/PhysRevD.77.023535 | KAIST-TH 2007/01 | hep-ph | null | We analyze how the spectrum of perturbations produced in a multi-component
modular inflation model proposed by Kadota and Stewart depends on couplings
between the two moduli. Although some simple direct couplings give essentially
the same results as the original model, $dn/d\ln k \propto n-1$, simple
indirect couplings produce a power law spectrum, $n-1 = \textrm{constant}$,
which can naturally be close to scale invariant.
| [
{
"created": "Thu, 25 Jan 2007 08:19:30 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Jun 2007 14:02:37 GMT",
"version": "v2"
}
] | 2008-02-12 | [
[
"Park",
"Wan-Il",
""
],
[
"Stewart",
"Ewan D.",
""
]
] | We analyze how the spectrum of perturbations produced in a multi-component modular inflation model proposed by Kadota and Stewart depends on couplings between the two moduli. Although some simple direct couplings give essentially the same results as the original model, $dn/d\ln k \propto n-1$, simple indirect couplings produce a power law spectrum, $n-1 = \textrm{constant}$, which can naturally be close to scale invariant. |
2403.17039 | Piotr Lebiedowicz | Piotr Lebiedowicz, Antoni Szczurek, Otto Nachtmann | Exclusive Bremsstrahlung of One and Two Photons in Proton-Proton
Collisions | 10 pages, 6 figures, presented by A. Szczurek at XXX Cracow EPIPHANY
Conference on Precision Physics at High Energy Colliders, Krakow, Poland,
January 8-12, 2024 | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We discuss the diffractive bremsstrahlung of a single photon in the $pp \to
pp \gamma$ reaction at LHC energies and at forward photon rapidities. We
compare the results for our standard approach, based on QFT and the
tensor-Pomeron model, with two versions of soft-photon approximations, SPA1 and
SPA2, where the radiative amplitudes contain only the leading terms
proportional to $\omega^{-1}$ (the inverse of the photon energy). SPA1, which
does not have the correct energy-momentum relations, performs surprisingly well
in the kinematic range considered, namely at very forward photon rapidities and
$0.02 < \xi_{1,2} < 0.1$, the relative energy loss of the protons,
corresponding to small values of the photon transverse momentum. Azimuthal
correlations between outgoing particles are presented. We discuss also the role
of the $p p \to p p \pi^0$ background for single photon production. We discuss
also the possibility of a measurement of the $pp \to pp \gamma \gamma$
reaction. Our predictions can be verified by ATLAS-LHCf combined experiments.
| [
{
"created": "Mon, 25 Mar 2024 11:41:10 GMT",
"version": "v1"
}
] | 2024-03-27 | [
[
"Lebiedowicz",
"Piotr",
""
],
[
"Szczurek",
"Antoni",
""
],
[
"Nachtmann",
"Otto",
""
]
] | We discuss the diffractive bremsstrahlung of a single photon in the $pp \to pp \gamma$ reaction at LHC energies and at forward photon rapidities. We compare the results for our standard approach, based on QFT and the tensor-Pomeron model, with two versions of soft-photon approximations, SPA1 and SPA2, where the radiative amplitudes contain only the leading terms proportional to $\omega^{-1}$ (the inverse of the photon energy). SPA1, which does not have the correct energy-momentum relations, performs surprisingly well in the kinematic range considered, namely at very forward photon rapidities and $0.02 < \xi_{1,2} < 0.1$, the relative energy loss of the protons, corresponding to small values of the photon transverse momentum. Azimuthal correlations between outgoing particles are presented. We discuss also the role of the $p p \to p p \pi^0$ background for single photon production. We discuss also the possibility of a measurement of the $pp \to pp \gamma \gamma$ reaction. Our predictions can be verified by ATLAS-LHCf combined experiments. |
hep-ph/0211441 | Pscar J. P. Eboli | A. Alves, O. Eboli, and T. Plehn | Stop Lepton Associated Production at Hadron Colliders | 10 pages and 4 figures | Phys.Lett.B558:165-172,2003 | 10.1016/S0370-2693(03)00266-1 | CERN-TH/2002-344; IFT-P.093/2002; MADPH-02-1309 | hep-ph | null | At hadron colliders, the search for R-parity violating supersymmetry can
probe scalar masses beyond what is covered by pair production processes. We
evaluate the next-to-leading order SUSY-QCD corrections to the associated stop
or sbottom production with a lepton through R-parity violating interactions. We
show that higher order corrections render the theoretical predictions more
stable with respect to variations of the renormalization and factorization
scales and that the total cross section is enhanced by a factor up to 70% at
the Tevatron and 50% at the LHC. We investigate in detail how the heavy
supersymmetric states decouple from the next-to-leading order process, which
gives rise to a theory with an additional scalar leptoquark. In this scenario
the inclusion of higher order QCD corrections increases the Tevatron reach on
leptoquark masses by up to 40 GeV and the LHC reach by up to 200 GeV.
| [
{
"created": "Thu, 28 Nov 2002 13:54:40 GMT",
"version": "v1"
}
] | 2011-01-27 | [
[
"Alves",
"A.",
""
],
[
"Eboli",
"O.",
""
],
[
"Plehn",
"T.",
""
]
] | At hadron colliders, the search for R-parity violating supersymmetry can probe scalar masses beyond what is covered by pair production processes. We evaluate the next-to-leading order SUSY-QCD corrections to the associated stop or sbottom production with a lepton through R-parity violating interactions. We show that higher order corrections render the theoretical predictions more stable with respect to variations of the renormalization and factorization scales and that the total cross section is enhanced by a factor up to 70% at the Tevatron and 50% at the LHC. We investigate in detail how the heavy supersymmetric states decouple from the next-to-leading order process, which gives rise to a theory with an additional scalar leptoquark. In this scenario the inclusion of higher order QCD corrections increases the Tevatron reach on leptoquark masses by up to 40 GeV and the LHC reach by up to 200 GeV. |
2202.13648 | Shuai Zhao | Ji Xu, Xi-Ruo Zhang, Shuai Zhao | Inverse moment of the $B$-meson quasi distribution amplitude | 7 pages, 1 figure. Discussions extended. References updated. Accepted
for publication in Physical Review D | Phys. Rev. D 106, L011503 (2022) | 10.1103/PhysRevD.106.L011503 | JLAB-THY-22-3569 | hep-ph hep-lat | http://creativecommons.org/licenses/by/4.0/ | We perform a study on the structure of inverse moment (IM) of quasi
distributions, by taking $B$-meson quasi distribution amplitude (quasi-DA) as
an example. Based on a one-loop calculation, we derive the renormalization
group equation and velocity evolution equation for the first IM of quasi-DA. We
find that, in the large velocity limit, the first IM of $B$-meson quasi-DA can
be factorized into IM as well as logarithmic moments of light-cone distribution
amplitude (LCDA), accompanied by short distance coefficients. Our results can
be useful either in understanding the patterns of perturbative matching in
Large Momentum Effective Theory or evaluating inverse moment of $B$-meson LCDA
on the lattice.
| [
{
"created": "Mon, 28 Feb 2022 09:44:32 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Jul 2022 20:59:59 GMT",
"version": "v2"
}
] | 2022-07-29 | [
[
"Xu",
"Ji",
""
],
[
"Zhang",
"Xi-Ruo",
""
],
[
"Zhao",
"Shuai",
""
]
] | We perform a study on the structure of inverse moment (IM) of quasi distributions, by taking $B$-meson quasi distribution amplitude (quasi-DA) as an example. Based on a one-loop calculation, we derive the renormalization group equation and velocity evolution equation for the first IM of quasi-DA. We find that, in the large velocity limit, the first IM of $B$-meson quasi-DA can be factorized into IM as well as logarithmic moments of light-cone distribution amplitude (LCDA), accompanied by short distance coefficients. Our results can be useful either in understanding the patterns of perturbative matching in Large Momentum Effective Theory or evaluating inverse moment of $B$-meson LCDA on the lattice. |
hep-ph/0312164 | Grzegorz Wilk | O.V.Utyuzh, G.Wilk and Z.Wlodarczyk | How to model BEC numrically? | Contribution to Second Warsaw Meeting on Particle Correlations and
Resonances in Heavy Ion Collisions, Warsaw, 15-18 October, 2003, Poland | Nukleonika 49 (2004) S35 | null | null | hep-ph nucl-th | null | The new method of numerical modelling of Bose-Einstein correlations observed
in all kinds of multiparticle production processes is proposed.
| [
{
"created": "Fri, 12 Dec 2003 11:28:41 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Utyuzh",
"O. V.",
""
],
[
"Wilk",
"G.",
""
],
[
"Wlodarczyk",
"Z.",
""
]
] | The new method of numerical modelling of Bose-Einstein correlations observed in all kinds of multiparticle production processes is proposed. |
1607.05291 | Marco Zaro | Celine Degrande, Rikkert Frederix, Valentin Hirschi, Maria Ubiali,
Marius Wiesemann, Marco Zaro | Accurate predictions for charged Higgs production: closing the
$m_{H^{\pm}}\sim m_t$ window | 10 pages including references, version accepted for publication on
Phys. Lett. B | Phys.Lett. B772 (2017) 87-92 | 10.1016/j.physletb.2017.06.037 | Cavendish-HEP-16/12, IPPP/16/62, SLAC-PUB-16769, TUM-HEP-1055/16,
ZH-TH-25/16 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present predictions for the total cross section for the production of a
charged Higgs boson in the intermediate-mass range ($m_{H^{\pm}}\sim m_t$) at
the LHC, focusing on a type-II two-Higgs-doublet model. Results are obtained at
next-to-leading order (NLO) accuracy in QCD perturbation theory, by studying
the full process $pp\to H^\pm W^\mp b \bar b$ in the complex-(top)-mass scheme
with massive bottom quarks. Compared to lowest-order predictions, NLO
corrections have a sizeable impact: they increase the cross section by roughly
50\% and reduce uncertainties due to scale variations by more than a factor of
two. Our computation reliably interpolates between the low- and high-mass
regime. Our results provide the first NLO prediction for charged Higgs
production in the intermediate-mass range and therefore allow to have NLO
accurate predictions in the full $m_{H^{\pm}}$ range. The extension of our
results to different realisations of the two-Higgs-doublet model or to the
supersymmetric case is also discussed.
| [
{
"created": "Mon, 18 Jul 2016 20:00:11 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Jun 2017 13:04:43 GMT",
"version": "v2"
}
] | 2017-06-29 | [
[
"Degrande",
"Celine",
""
],
[
"Frederix",
"Rikkert",
""
],
[
"Hirschi",
"Valentin",
""
],
[
"Ubiali",
"Maria",
""
],
[
"Wiesemann",
"Marius",
""
],
[
"Zaro",
"Marco",
""
]
] | We present predictions for the total cross section for the production of a charged Higgs boson in the intermediate-mass range ($m_{H^{\pm}}\sim m_t$) at the LHC, focusing on a type-II two-Higgs-doublet model. Results are obtained at next-to-leading order (NLO) accuracy in QCD perturbation theory, by studying the full process $pp\to H^\pm W^\mp b \bar b$ in the complex-(top)-mass scheme with massive bottom quarks. Compared to lowest-order predictions, NLO corrections have a sizeable impact: they increase the cross section by roughly 50\% and reduce uncertainties due to scale variations by more than a factor of two. Our computation reliably interpolates between the low- and high-mass regime. Our results provide the first NLO prediction for charged Higgs production in the intermediate-mass range and therefore allow to have NLO accurate predictions in the full $m_{H^{\pm}}$ range. The extension of our results to different realisations of the two-Higgs-doublet model or to the supersymmetric case is also discussed. |
hep-ph/9309206 | Andrei Johansen | Minos Axenides, A. Johansen and H.B. Nielsen | The $SU(2)$ Global Anomaly Through Level Circling | 14 pages, NBI-HE-93-51 | Mod.Phys.Lett. A9 (1994) 501-514 | 10.1142/S0217732394003737 | null | hep-ph | null | We discuss a novel manifestation of the $SU(2)$ global anomaly in an $SU(2)$
gauge theory with an odd number of chiral quark doublets and arbitrary Yukawa
couplings. We argue that the massive 4-dim.($D=4$) Euclidean Dirac operator is
nonhermitean with its spectrum of eigenvalues $(\lambda,-\lambda)$ lying in
pairs in the complex plane. Consequently the existence of an odd number of
normalizable zero modes of the 5-dim.($D=5$) massive Dirac operator is
equivalent to a fermionic level exchange phenomenon, level ``circling'', under
continuous topologically nontrivial deformations of the external gauge field.
More generally global anomalies are a manifestation of fermionic level
``circling'' in any $SP(2n)$ gauge theory with an odd number of massive
fermions in the spinor representation and arbitrary Yukawa couplings.
| [
{
"created": "Wed, 1 Sep 1993 21:27:52 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Axenides",
"Minos",
""
],
[
"Johansen",
"A.",
""
],
[
"Nielsen",
"H. B.",
""
]
] | We discuss a novel manifestation of the $SU(2)$ global anomaly in an $SU(2)$ gauge theory with an odd number of chiral quark doublets and arbitrary Yukawa couplings. We argue that the massive 4-dim.($D=4$) Euclidean Dirac operator is nonhermitean with its spectrum of eigenvalues $(\lambda,-\lambda)$ lying in pairs in the complex plane. Consequently the existence of an odd number of normalizable zero modes of the 5-dim.($D=5$) massive Dirac operator is equivalent to a fermionic level exchange phenomenon, level ``circling'', under continuous topologically nontrivial deformations of the external gauge field. More generally global anomalies are a manifestation of fermionic level ``circling'' in any $SP(2n)$ gauge theory with an odd number of massive fermions in the spinor representation and arbitrary Yukawa couplings. |
hep-ph/0208212 | Michael Klasen | Stefan Berge, Michael Klasen (Hamburg University) | Gluino Pair Production at Linear e^+e^- Colliders | 22 pages, 9 figures | Phys.Rev.D66:115014,2002 | 10.1103/PhysRevD.66.115014 | DESY 02-119 | hep-ph hep-ex | null | We study the potential of high-energy linear $e^+e^-$ colliders for the
production of gluino pairs within the Minimal Supersymmetric Standard Model
(MSSM). In this model, the process $e^+e^-\to\tilde{g}\tilde{g}$ is mediated by
quark/squark loops, dominantly of the third generation, where the mixing of
left- and right-handed states can become large. Taking into account realistic
beam polarization effects, photon and $Z^0$-boson exchange, and current mass
exclusion limits, we scan the MSSM parameter space for various $e^+e^-$
center-of-mass energies to determine the regions, where gluino production
should be visible.
| [
{
"created": "Fri, 23 Aug 2002 09:58:24 GMT",
"version": "v1"
}
] | 2011-03-23 | [
[
"Berge",
"Stefan",
"",
"Hamburg University"
],
[
"Klasen",
"Michael",
"",
"Hamburg University"
]
] | We study the potential of high-energy linear $e^+e^-$ colliders for the production of gluino pairs within the Minimal Supersymmetric Standard Model (MSSM). In this model, the process $e^+e^-\to\tilde{g}\tilde{g}$ is mediated by quark/squark loops, dominantly of the third generation, where the mixing of left- and right-handed states can become large. Taking into account realistic beam polarization effects, photon and $Z^0$-boson exchange, and current mass exclusion limits, we scan the MSSM parameter space for various $e^+e^-$ center-of-mass energies to determine the regions, where gluino production should be visible. |
hep-ph/0207024 | Nicolas Cosme | N.Cosme, J.-M. Frere, L. Lopez Honorez | CP Violation from Dimensional Reduction: Examples in 4+1 Dimensions | 6 pages, typos corrected, 1 reference added | Phys.Rev.D68:096001,2003 | 10.1103/PhysRevD.68.096001 | null | hep-ph | null | We provide simple examples of the generation of complex mass terms and hence
CP violation through dimensional reduction.
| [
{
"created": "Mon, 1 Jul 2002 15:01:00 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Jul 2002 12:03:12 GMT",
"version": "v2"
},
{
"created": "Fri, 29 Nov 2002 12:00:09 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Cosme",
"N.",
""
],
[
"Frere",
"J. -M.",
""
],
[
"Honorez",
"L. Lopez",
""
]
] | We provide simple examples of the generation of complex mass terms and hence CP violation through dimensional reduction. |
hep-ph/0210188 | Yoshio Koide | Yoshio Koide and Joe Sato | An SU(5) SUSY Model with R-Parity Violation and Radiatively Induced
Neutrino Masses | 6 pages, Revtex, no figure | null | null | CERN-TH/2002-274; US-02-11; STUPP-02-171 | hep-ph | null | The radiatively induced neutrino mass matrix is investigated on the basis of
an SU(5) SUSY model. In order to evade the proton decay, an ansatz based on a
discrete symmetry $Z_2$ is assumed: although, at the unification scale, we have
two types of superfields $\Psi_{L(\pm)}=\bar{5}_{L(\pm)}+10_{L(\pm)}$, which
are transformed as $\Psi_{L(\pm)} \to \pm \Psi_{L(\pm)}$ under the discrete
symmetry Z$_2$, the particles $\Psi_{L(+)}$ are decoupled after the SU(5)
symmetry is broken, so that our quarks and leptons belong to \Psi_{L(-)}. The
R-parity-violating terms for our quarks and leptons \Psi_{L(-)} are basically
forbidden under the symmetry Z_2. However, we assume that mixings between
members of \Psi_{L(+)} and those of \Psi_{L(-)} are in part caused after SU(5)
is broken. As a result, the R-parity-violating interactions are in part
allowed, so that the neutrino masses are radiatively generated, while the
proton decay due to the R-parity violating terms is still forbidden because the
term d_R^c d_R^c u_R^c has z=-1.
| [
{
"created": "Sat, 12 Oct 2002 04:45:18 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Koide",
"Yoshio",
""
],
[
"Sato",
"Joe",
""
]
] | The radiatively induced neutrino mass matrix is investigated on the basis of an SU(5) SUSY model. In order to evade the proton decay, an ansatz based on a discrete symmetry $Z_2$ is assumed: although, at the unification scale, we have two types of superfields $\Psi_{L(\pm)}=\bar{5}_{L(\pm)}+10_{L(\pm)}$, which are transformed as $\Psi_{L(\pm)} \to \pm \Psi_{L(\pm)}$ under the discrete symmetry Z$_2$, the particles $\Psi_{L(+)}$ are decoupled after the SU(5) symmetry is broken, so that our quarks and leptons belong to \Psi_{L(-)}. The R-parity-violating terms for our quarks and leptons \Psi_{L(-)} are basically forbidden under the symmetry Z_2. However, we assume that mixings between members of \Psi_{L(+)} and those of \Psi_{L(-)} are in part caused after SU(5) is broken. As a result, the R-parity-violating interactions are in part allowed, so that the neutrino masses are radiatively generated, while the proton decay due to the R-parity violating terms is still forbidden because the term d_R^c d_R^c u_R^c has z=-1. |
hep-ph/9404273 | Hoi-Kwong Lo | Hoi-Kwong LO | Scattering from Electroweak Strings | Replaced with revised version "Tex with phyzzx, 18 pages,
CALT-68-1921 Non-trivial changes made: discussion on axion strings corrected.
Overlap with a recently revised version of hep-ph/9311202 noted | Phys.Rev. D51 (1995) 802-809 | 10.1103/PhysRevD.51.802 | null | hep-ph hep-th | null | The scattering of a charged fermion from an electroweak string is studied.
Owing to an amplification of the wave function at the core radius, the cross
sections for helicity flip processes can be largely enhanced. For $0 <\sin^2
\theta_w < 1/2 $ (where $\theta_w$ is the Weinberg angle), $\omega \sim k \sim
m_e$ and $kR \ll 1$, we show that the helicity flip differential cross section
for electrons is of the order $m_e^{-1}$ and is independent of angle. We
compare our results with those obtained in calculations of rates for baryon
number violating processes in the core of a cosmic string. In that case, while
the enhancement is a general phenomenon, its actual magnitude is extremely
sensitive to the fractional flux carried by the string core. Apart from showing
the existence of a similar enhancement effect for non-topological strings, our
results indicate that in some models the magnitude of enhancement can be
rendered much less sensitive to the value of the parameters in the theories.
Scattering of particles off semi-local strings and axion strings are also
considered.
| [
{
"created": "Fri, 15 Apr 1994 23:21:29 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Apr 1994 23:26:30 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"LO",
"Hoi-Kwong",
""
]
] | The scattering of a charged fermion from an electroweak string is studied. Owing to an amplification of the wave function at the core radius, the cross sections for helicity flip processes can be largely enhanced. For $0 <\sin^2 \theta_w < 1/2 $ (where $\theta_w$ is the Weinberg angle), $\omega \sim k \sim m_e$ and $kR \ll 1$, we show that the helicity flip differential cross section for electrons is of the order $m_e^{-1}$ and is independent of angle. We compare our results with those obtained in calculations of rates for baryon number violating processes in the core of a cosmic string. In that case, while the enhancement is a general phenomenon, its actual magnitude is extremely sensitive to the fractional flux carried by the string core. Apart from showing the existence of a similar enhancement effect for non-topological strings, our results indicate that in some models the magnitude of enhancement can be rendered much less sensitive to the value of the parameters in the theories. Scattering of particles off semi-local strings and axion strings are also considered. |
hep-ph/0509071 | Carl R. Schmidt | Roshan Foadi and Carl Schmidt | An Effective Higgsless Theory: Satisfying Electroweak Constraints and a
Heavy Top Quark | 26 pages, JHEP format | Phys.Rev. D73 (2006) 075011 | 10.1103/PhysRevD.73.075011 | MSUHEP-050824 | hep-ph | null | The main challenge faced by Higgsless models of electroweak symmetry breaking
is to reconcile the experimental constraints imposed by the precision
electroweak data and the top quark phenomenology with the unitarity constraints
imposed by longitudinal gauge boson scattering amplitudes. In this paper we
expand on previous work, giving details of how delocalized fermions can be used
to adjust the $S$ parameter to zero, while keeping the $T$ and $U$ parameters
naturally suppressed. We also show that it is possible to obtain the top quark
mass, without affecting the delay of unitarity violation of the $W^+ W^-\to
W^+W^-$ scattering amplitude, by separating the mass scales of the fermion
sector ($1/R_f$) from that of the gauge sector ($1/R_g$). The fermion sector
scale $1/R_f$ is only weakly constrained by unitarity of the $t\bar{t}\to W^+
W^-$ scattering amplitude; thus the ratio $R_g/R_f$ can be quite large, and the
top mass can be easily achieved. Anomalous right-handed couplings involving the
third generation quarks also avoid constraints from experimental data if
$1/R_f$ is sufficiently large.
| [
{
"created": "Thu, 8 Sep 2005 13:54:29 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Foadi",
"Roshan",
""
],
[
"Schmidt",
"Carl",
""
]
] | The main challenge faced by Higgsless models of electroweak symmetry breaking is to reconcile the experimental constraints imposed by the precision electroweak data and the top quark phenomenology with the unitarity constraints imposed by longitudinal gauge boson scattering amplitudes. In this paper we expand on previous work, giving details of how delocalized fermions can be used to adjust the $S$ parameter to zero, while keeping the $T$ and $U$ parameters naturally suppressed. We also show that it is possible to obtain the top quark mass, without affecting the delay of unitarity violation of the $W^+ W^-\to W^+W^-$ scattering amplitude, by separating the mass scales of the fermion sector ($1/R_f$) from that of the gauge sector ($1/R_g$). The fermion sector scale $1/R_f$ is only weakly constrained by unitarity of the $t\bar{t}\to W^+ W^-$ scattering amplitude; thus the ratio $R_g/R_f$ can be quite large, and the top mass can be easily achieved. Anomalous right-handed couplings involving the third generation quarks also avoid constraints from experimental data if $1/R_f$ is sufficiently large. |
hep-ph/0204162 | Muneyuki Ishida | Keiji Igi (Kanagawa univ.) and Muneyuki Ishida (Tokyo Institute of
Tech) | Do the pi N Total Cross Sections Increase Like log nu or log2 nu at High
Energies ? | Talk presented at Moriond conf. 2002. 4 pages, 1 eps figure, uses
moriond.sty | null | null | null | hep-ph | null | We propose to use rich informations on pi p total cross sections below N=10
GeV in order to investigate whether these cross sections increase like log nu
or log2 nu at high energies. A finite-energy sum rule (FESR) which is derived
in the spirit of the P' sum rule as well as the n=1 moment FESR have been
required to constrain the high-energy parameters. We then searched for the best
fit of pi p total cross sections above 70 GeV in terms of high-energy
parameters constrained by these two FESR. We can conclude that our analysis
strongly favours the log2 nu behaviors satisfying the Froissart unitarity
bound.
| [
{
"created": "Mon, 15 Apr 2002 03:19:33 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Igi",
"Keiji",
"",
"Kanagawa univ."
],
[
"Ishida",
"Muneyuki",
"",
"Tokyo Institute of\n Tech"
]
] | We propose to use rich informations on pi p total cross sections below N=10 GeV in order to investigate whether these cross sections increase like log nu or log2 nu at high energies. A finite-energy sum rule (FESR) which is derived in the spirit of the P' sum rule as well as the n=1 moment FESR have been required to constrain the high-energy parameters. We then searched for the best fit of pi p total cross sections above 70 GeV in terms of high-energy parameters constrained by these two FESR. We can conclude that our analysis strongly favours the log2 nu behaviors satisfying the Froissart unitarity bound. |
1808.09456 | Sacha Davidson | Adrien Auriol, Sacha Davidson and Georg Raffelt | Axion absorption and the spin temperature of primordial hydrogen | 7 pages, version accepted for publication | null | null | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An absorption dip in the spectrum of the cosmic microwave background observed
by the EDGES experiment suggests an unexplained reduction of the hydrogen spin
temperature at cosmic redshift z ~ 17. The mass of dark-matter axions could
correspond to the hyperfine splitting of 5.9 micro-eV, between the triplet (H1)
and singlet (H0) state. We calculate the rate for a+ H0 <-> H1 in two ways, and
find that it is orders of magnitude smaller than the CMB-mediated transition
rate, so irrelevant. As a result, this process cannot be used to rule in or out
dark matter axions of mass = hyperfine splitting. The axion rate nonetheless
has interesting features, for example, on balance it heats the spin
temperature, and the axion couplings to protons and electrons contribute on
equal footing.
| [
{
"created": "Tue, 28 Aug 2018 18:00:02 GMT",
"version": "v1"
},
{
"created": "Sun, 20 Jan 2019 10:31:03 GMT",
"version": "v2"
}
] | 2019-01-23 | [
[
"Auriol",
"Adrien",
""
],
[
"Davidson",
"Sacha",
""
],
[
"Raffelt",
"Georg",
""
]
] | An absorption dip in the spectrum of the cosmic microwave background observed by the EDGES experiment suggests an unexplained reduction of the hydrogen spin temperature at cosmic redshift z ~ 17. The mass of dark-matter axions could correspond to the hyperfine splitting of 5.9 micro-eV, between the triplet (H1) and singlet (H0) state. We calculate the rate for a+ H0 <-> H1 in two ways, and find that it is orders of magnitude smaller than the CMB-mediated transition rate, so irrelevant. As a result, this process cannot be used to rule in or out dark matter axions of mass = hyperfine splitting. The axion rate nonetheless has interesting features, for example, on balance it heats the spin temperature, and the axion couplings to protons and electrons contribute on equal footing. |
hep-ph/0502188 | Simon Albino | S. Albino, B.A. Kniehl and G. Kramer | Fragmentation Functions for Light Charged Hadrons with Complete Quark
Flavour Separation | null | Nucl.Phys.B725:181-206,2005 | 10.1016/j.nuclphysb.2005.07.010 | null | hep-ph | null | We present new sets of next-to-leading order fragmentation functions
describing the production of charged pions, kaons and protons from the gluon
and from each of the quarks, obtained by fitting to all relevant data sets from
e+ e- annihilation. The individual light quark flavour fragmentation functions
are obtained phenomenologically for the first time by including in the data the
light quark tagging probabilities obtained by the OPAL Collaboration.
| [
{
"created": "Mon, 21 Feb 2005 13:57:04 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Sep 2005 13:57:05 GMT",
"version": "v2"
}
] | 2010-04-06 | [
[
"Albino",
"S.",
""
],
[
"Kniehl",
"B. A.",
""
],
[
"Kramer",
"G.",
""
]
] | We present new sets of next-to-leading order fragmentation functions describing the production of charged pions, kaons and protons from the gluon and from each of the quarks, obtained by fitting to all relevant data sets from e+ e- annihilation. The individual light quark flavour fragmentation functions are obtained phenomenologically for the first time by including in the data the light quark tagging probabilities obtained by the OPAL Collaboration. |
1512.00068 | Aniket Joglekar | Peisi Huang, Aniket Joglekar, Bing Li, Carlos E.M. Wagner | Probing the Electroweak Phase Transition at the LHC | 43 pages, 4 figures | Phys. Rev. D 93, 055049 (2016) | 10.1103/PhysRevD.93.055049 | EFI-15-37 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the correlation between the value of the triple Higgs coupling and
the nature of the electroweak phase transition. We use an effective potential
approach, including higher order, non-renormalizable terms coming from
integrating out new physics. We show that if only the dimension six operators
are considered, large positive deviations of the triple Higgs coupling from its
Standard Model (SM) value are predicted in the regions of parameter space
consistent with a strong first order electroweak phase transition (SFOEPT). We
also show that at higher orders sizable and negative deviations of the triple
Higgs coupling may be obtained, and the sign of the corrections tends to be
correlated with the order of the phase transition. We also consider a singlet
extension of the SM, which allows us to establish the connection with the
effective field theory (EFT) approach and analyze the limits of its validity.
Furthermore, we study how to probe the triple Higgs coupling from the double
Higgs production at the LHC. We show that selective cuts in the invariant mass
of the two Higgs bosons should be used, to maximize the sensitivity for values
of the triple Higgs coupling significantly different from the Standard Model
one.
| [
{
"created": "Mon, 30 Nov 2015 22:18:29 GMT",
"version": "v1"
}
] | 2016-04-06 | [
[
"Huang",
"Peisi",
""
],
[
"Joglekar",
"Aniket",
""
],
[
"Li",
"Bing",
""
],
[
"Wagner",
"Carlos E. M.",
""
]
] | We study the correlation between the value of the triple Higgs coupling and the nature of the electroweak phase transition. We use an effective potential approach, including higher order, non-renormalizable terms coming from integrating out new physics. We show that if only the dimension six operators are considered, large positive deviations of the triple Higgs coupling from its Standard Model (SM) value are predicted in the regions of parameter space consistent with a strong first order electroweak phase transition (SFOEPT). We also show that at higher orders sizable and negative deviations of the triple Higgs coupling may be obtained, and the sign of the corrections tends to be correlated with the order of the phase transition. We also consider a singlet extension of the SM, which allows us to establish the connection with the effective field theory (EFT) approach and analyze the limits of its validity. Furthermore, we study how to probe the triple Higgs coupling from the double Higgs production at the LHC. We show that selective cuts in the invariant mass of the two Higgs bosons should be used, to maximize the sensitivity for values of the triple Higgs coupling significantly different from the Standard Model one. |
1903.12192 | Alberto Tonero Dr. | Kevin Earl, Chee Sheng Fong, Thomas Gregoire and Alberto Tonero | Mirror Dirac leptogenesis | 24 pages, 3 figures; abstract and introduction modified, reference to
an earlier work on the subject added, section and detailed discussion about
flavor enhancement effects added; JCAP version | null | 10.1088/1475-7516/2020/03/036 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a mirror world scenario, in which light Dirac neutrinos are
generated from a seesaw mechanism and leptogenesis occurs at high scale without
violating lepton number. After leptogenesis, the conservation laws of the
theory imply the visible baryon-minus-lepton asymmetry to be equal to the
mirror baryon-minus-lepton asymmetry. We extend previous work by presenting a
detailed study of this Dirac leptogenesis mechanism by constructing the full
set of Boltzmann Equations for both cases of unflavored and flavored regimes.
We show that $Z_2$ breaking and lepton/mirror lepton flavor effects can be
exploited to enhance the final baryon-minus-lepton asymmetry in our world by
several orders of magnitude.
| [
{
"created": "Thu, 28 Mar 2019 18:00:31 GMT",
"version": "v1"
},
{
"created": "Tue, 7 May 2019 21:57:03 GMT",
"version": "v2"
},
{
"created": "Sat, 21 Mar 2020 20:13:39 GMT",
"version": "v3"
}
] | 2020-03-24 | [
[
"Earl",
"Kevin",
""
],
[
"Fong",
"Chee Sheng",
""
],
[
"Gregoire",
"Thomas",
""
],
[
"Tonero",
"Alberto",
""
]
] | We consider a mirror world scenario, in which light Dirac neutrinos are generated from a seesaw mechanism and leptogenesis occurs at high scale without violating lepton number. After leptogenesis, the conservation laws of the theory imply the visible baryon-minus-lepton asymmetry to be equal to the mirror baryon-minus-lepton asymmetry. We extend previous work by presenting a detailed study of this Dirac leptogenesis mechanism by constructing the full set of Boltzmann Equations for both cases of unflavored and flavored regimes. We show that $Z_2$ breaking and lepton/mirror lepton flavor effects can be exploited to enhance the final baryon-minus-lepton asymmetry in our world by several orders of magnitude. |
hep-ph/0612203 | Sergei Gninenko | S.N. Gninenko, N.V. Krasnikov, A. Rubbia | Search for millicharged particles in reactor neutrino experiments: a
probe of the PVLAS anomaly | 4 pages, version to appear in PRD | Phys.Rev.D75:075014,2007 | 10.1103/PhysRevD.75.075014 | null | hep-ph | null | It has been recently suggested that the vacuum magnetic dichroism observed by
the PVLAS experiment could be explained by the pair production of a new light,
m ~0.1 eV, millicharged, q ~ 3 10^{-6} e, fermions. In addition, it has been
pointed out that millicharged particles with q > 10^{-9} e appear naturally in
models based on the string theory. We show that low energy reactor neutrino
experiments provide a sensitive probe of millicharged particles. Considering,
as an example, recent results of the TEXONO experiment searching for neutrino
magnetic moment, a new upper bound q < 10^{-5} e for the mass region m < 1 keV
is derived. These results enhance motivations for a more sensitive search for
such particles in near future experiments. Furthemore, a direct experimental
limit on the electric charge of the electron antineutrino q < 3.7 10^{-12} e is
obtained.
| [
{
"created": "Sun, 17 Dec 2006 08:55:20 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Dec 2006 10:29:35 GMT",
"version": "v2"
},
{
"created": "Thu, 29 Mar 2007 16:13:19 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Gninenko",
"S. N.",
""
],
[
"Krasnikov",
"N. V.",
""
],
[
"Rubbia",
"A.",
""
]
] | It has been recently suggested that the vacuum magnetic dichroism observed by the PVLAS experiment could be explained by the pair production of a new light, m ~0.1 eV, millicharged, q ~ 3 10^{-6} e, fermions. In addition, it has been pointed out that millicharged particles with q > 10^{-9} e appear naturally in models based on the string theory. We show that low energy reactor neutrino experiments provide a sensitive probe of millicharged particles. Considering, as an example, recent results of the TEXONO experiment searching for neutrino magnetic moment, a new upper bound q < 10^{-5} e for the mass region m < 1 keV is derived. These results enhance motivations for a more sensitive search for such particles in near future experiments. Furthemore, a direct experimental limit on the electric charge of the electron antineutrino q < 3.7 10^{-12} e is obtained. |
hep-ph/0111007 | Jonathan Thomas Lenaghan | J.T. Lenaghan | The $\theta$-Vacua and the Leutwyler--Smilga Scaling Regime | 2 pages, contribution to the International Conference on Statistical
QCD, Bielefeld, Germany, 26-30 Aug 2001 | null | null | null | hep-ph | null | The partition function of QCD is studied in the Leutwyler--Smilga scaling
regime for an arbitrary number of quark flavors and masses including the
contributions from all winding numbers. For $N_f=2$ and degenerate quark
masses, the partition function becomes independent of the quark masses at
$\theta=\pi$ and subsequently the scalar chiral condensate vanishes. There is a
discontinuity at $\theta=\pi$ in the first derivative of the energy density
with respect to $\theta$ corresponding to the first--order phase transition in
which CP is spontaneously broken, known as Dashen's phenomena. These properties
are found to be insensitive to both the pattern of chiral symmetry breaking and
the representation of the quark fields.
| [
{
"created": "Thu, 1 Nov 2001 10:39:45 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lenaghan",
"J. T.",
""
]
] | The partition function of QCD is studied in the Leutwyler--Smilga scaling regime for an arbitrary number of quark flavors and masses including the contributions from all winding numbers. For $N_f=2$ and degenerate quark masses, the partition function becomes independent of the quark masses at $\theta=\pi$ and subsequently the scalar chiral condensate vanishes. There is a discontinuity at $\theta=\pi$ in the first derivative of the energy density with respect to $\theta$ corresponding to the first--order phase transition in which CP is spontaneously broken, known as Dashen's phenomena. These properties are found to be insensitive to both the pattern of chiral symmetry breaking and the representation of the quark fields. |
1809.01198 | Iason Baldes | Iason Baldes, Camilo Garcia-Cely | Strong gravitational radiation from a simple dark matter model | 30 pages, 12 figures | JHEP 1905 (2019) 190 | 10.1007/JHEP05(2019)190 | DESY 18-155 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A rather minimal possibility is that dark matter consists of the gauge bosons
of a spontaneously broken symmetry. Here we explore the possibility of
detecting the gravitational waves produced by the phase transition associated
with such breaking. Concretely, we focus on the scenario based on an $SU(2)_D$
group and argue that it is a case study for the sensitivity of future
gravitational wave observatories to phase transitions associated with dark
matter. This is because there are few parameters and those fixing the relic
density also determine the effective potential establishing the strength of the
phase transition. Particularly promising for LISA and even the Einstein
Telescope is the super-cool dark matter regime, with DM masses above
$\mathcal{O}$(100) TeV, for which we find that the gravitational wave signal is
notably strong. In our analysis, we include the effect of astrophysical
foregrounds, which are often ignored in the context of phase transitions.
| [
{
"created": "Tue, 4 Sep 2018 18:57:44 GMT",
"version": "v1"
},
{
"created": "Wed, 29 May 2019 09:54:42 GMT",
"version": "v2"
}
] | 2019-05-30 | [
[
"Baldes",
"Iason",
""
],
[
"Garcia-Cely",
"Camilo",
""
]
] | A rather minimal possibility is that dark matter consists of the gauge bosons of a spontaneously broken symmetry. Here we explore the possibility of detecting the gravitational waves produced by the phase transition associated with such breaking. Concretely, we focus on the scenario based on an $SU(2)_D$ group and argue that it is a case study for the sensitivity of future gravitational wave observatories to phase transitions associated with dark matter. This is because there are few parameters and those fixing the relic density also determine the effective potential establishing the strength of the phase transition. Particularly promising for LISA and even the Einstein Telescope is the super-cool dark matter regime, with DM masses above $\mathcal{O}$(100) TeV, for which we find that the gravitational wave signal is notably strong. In our analysis, we include the effect of astrophysical foregrounds, which are often ignored in the context of phase transitions. |
hep-ph/0310321 | Alexander Kalloniatis | A.C. Kalloniatis (CSSM, Adelaide), S.N. Nedelko (JINR, Dubna and
ITPIII, Erlangen) | Axial U(1) and spontaneous chiral symmetry breaking within a confining
model of the QCD vacuum | Contribution to the Workshop on Lattice Hadron Physics II, LHP2003,
Cairns, Australia July 22-July 30, 2003 | null | 10.1016/S0920-5632(03)02463-0 | null | hep-ph | null | A model for the QCD vacuum based on domain-like background gluon fields has
previously been developed and demonstrated to exhibit confinement of quarks and
strong correlation of the local chirality of quark modes and duality of the
background gluon field. On the boundary of the j-th domain, quark fluctuations
satisfy chirality violating boundary conditions parametrized by a chiral angle
$\alpha_j$ which is treated as a collective variable. The dependence of the
free energy of an ensemble of $N\to\infty$ domains on $\{\alpha_j, j=1... N\}$
is studied. For one massless flavour there are only two degenerate minima
($\alpha_j=0,\pi$ $\forall j$) due to the contribution of the anomaly to the
free energy, which suppresses the continuous U(1) degeneracy. The residual
discrete symmetry is spontaneously broken with a quark condensate of $-(238
{\rm{MeV}})^3.$ For $N_f$ massless flavours a continuous $SU(N_f)_L\times
SU(N_f)_R$ degeneracy appears, while the $U_A(1)$ direction remains suppressed.
| [
{
"created": "Wed, 29 Oct 2003 01:12:05 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Kalloniatis",
"A. C.",
"",
"CSSM, Adelaide"
],
[
"Nedelko",
"S. N.",
"",
"JINR, Dubna and\n ITPIII, Erlangen"
]
] | A model for the QCD vacuum based on domain-like background gluon fields has previously been developed and demonstrated to exhibit confinement of quarks and strong correlation of the local chirality of quark modes and duality of the background gluon field. On the boundary of the j-th domain, quark fluctuations satisfy chirality violating boundary conditions parametrized by a chiral angle $\alpha_j$ which is treated as a collective variable. The dependence of the free energy of an ensemble of $N\to\infty$ domains on $\{\alpha_j, j=1... N\}$ is studied. For one massless flavour there are only two degenerate minima ($\alpha_j=0,\pi$ $\forall j$) due to the contribution of the anomaly to the free energy, which suppresses the continuous U(1) degeneracy. The residual discrete symmetry is spontaneously broken with a quark condensate of $-(238 {\rm{MeV}})^3.$ For $N_f$ massless flavours a continuous $SU(N_f)_L\times SU(N_f)_R$ degeneracy appears, while the $U_A(1)$ direction remains suppressed. |
hep-ph/0306005 | Chihiro Sasaki | Chihiro Sasaki | Non-renormalization Theorem Originating in a New Fixed Point of the
Vector Manifestation | 9 pages, 2 figures; Title is changed to make the result clearer.
Conclusion does not change. Misleading use of terminology is clarified. This
is the final version accepted in Nucl. Phys. A | null | 10.1016/j.nuclphysa.2004.03.121 | DPNU-03-15 | hep-ph nucl-th | null | We study the pion velocity at the critical temperature of chiral symmetry
restoration in QCD. Starting from the premise that the bare effective field
theory is to be defined from the underlying QCD, we incorporate the effects of
Lorentz non-invariance into the bare theory by matching an effective field
theory to QCD at a suitable matching scale, and investigate how the Lorentz
non-invariance existing in the bare theory influences physical quantities.
Using the hidden local symmetry model as the effective field theory, where the
chiral symmetry restoration is realized as the vector manifestation (VM), we
find that the pion velocity at the critical temperature receives neither
quantum nor (thermal) hadronic corrections at the critical temperature even
when we start from the bare theory with Lorentz symmetry breaking. This is
likely the manifestation of a new fixed point in the Lorentz non-invariant
formulation of the VM.
| [
{
"created": "Sat, 31 May 2003 13:27:12 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Nov 2003 19:47:44 GMT",
"version": "v2"
},
{
"created": "Fri, 2 Apr 2004 14:36:53 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Sasaki",
"Chihiro",
""
]
] | We study the pion velocity at the critical temperature of chiral symmetry restoration in QCD. Starting from the premise that the bare effective field theory is to be defined from the underlying QCD, we incorporate the effects of Lorentz non-invariance into the bare theory by matching an effective field theory to QCD at a suitable matching scale, and investigate how the Lorentz non-invariance existing in the bare theory influences physical quantities. Using the hidden local symmetry model as the effective field theory, where the chiral symmetry restoration is realized as the vector manifestation (VM), we find that the pion velocity at the critical temperature receives neither quantum nor (thermal) hadronic corrections at the critical temperature even when we start from the bare theory with Lorentz symmetry breaking. This is likely the manifestation of a new fixed point in the Lorentz non-invariant formulation of the VM. |
hep-ph/0507108 | Cyrille Marquet | Cyrille Marquet | Small-x effects in forward-jet production at HERA | 4 pages, 2 figures, Proceedings of the XIIIth International Workshop
on Deep Inelastic Scattering (DIS05), Madison, Wisconsin, USA, April 27-May 1
2005 | null | 10.1063/1.2122148 | null | hep-ph | null | We investigate small-x effects in forward-jet production at HERA in the
two-hard-scale region kT ~ Q>>Lambda_QCD. We show that, despite describing
different energy regimes, both a BFKL parametrization and saturation
parametrizations describe well the H1 and ZEUS data for dsigma/dx published a
few years ago. This is confirmed when comparing the predictions to the latest
data.
| [
{
"created": "Fri, 8 Jul 2005 12:56:52 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Marquet",
"Cyrille",
""
]
] | We investigate small-x effects in forward-jet production at HERA in the two-hard-scale region kT ~ Q>>Lambda_QCD. We show that, despite describing different energy regimes, both a BFKL parametrization and saturation parametrizations describe well the H1 and ZEUS data for dsigma/dx published a few years ago. This is confirmed when comparing the predictions to the latest data. |
hep-ph/9502413 | null | G.H.Arakelyan, P.E.Volkovitsky | Charmed particle production in hadron-hadron collision | Latex,19 pages, 12figs. can be received by request | Z.Phys. A353 (1995) 87-101 | 10.1007/BF01297731 | YERPHI-1435(5)-95 | hep-ph | null | In the framework of Quark--Gluon--String Model developed recently in ITEP we
calculate spectra of charmed particles $D$, $D_s$, $\Lambda_c$, $\Xi_c$,
$\Omega_c$ in hadron--hadron collisions taking into account the decays of
$S$--wave resonances like $D^*$, $D^*_s$, $\Sigma_c$, $\Sigma^*_c$, $\Xi^*_c$,
$\Xi'_c$, and $\Omega^*_c$. We describe the bulk of the existing data on $D$,
$D^*$, and $\Lambda_c$ production in $\pi p$ and $pp$ collisions and predict
the yield of charmed particles in $\Sigma^-p$ and $\Xi^-p$ reactions at hyperon
beam energies of $340\;GeV/c$ and $600\;GeV/c$. Because of significant
production of baryon resonances our predictions for unfavored fragmentation
differ from predictions of other models which do not take resonance production
into account.
| [
{
"created": "Tue, 28 Feb 1995 15:56:15 GMT",
"version": "v1"
}
] | 2019-08-17 | [
[
"Arakelyan",
"G. H.",
""
],
[
"Volkovitsky",
"P. E.",
""
]
] | In the framework of Quark--Gluon--String Model developed recently in ITEP we calculate spectra of charmed particles $D$, $D_s$, $\Lambda_c$, $\Xi_c$, $\Omega_c$ in hadron--hadron collisions taking into account the decays of $S$--wave resonances like $D^*$, $D^*_s$, $\Sigma_c$, $\Sigma^*_c$, $\Xi^*_c$, $\Xi'_c$, and $\Omega^*_c$. We describe the bulk of the existing data on $D$, $D^*$, and $\Lambda_c$ production in $\pi p$ and $pp$ collisions and predict the yield of charmed particles in $\Sigma^-p$ and $\Xi^-p$ reactions at hyperon beam energies of $340\;GeV/c$ and $600\;GeV/c$. Because of significant production of baryon resonances our predictions for unfavored fragmentation differ from predictions of other models which do not take resonance production into account. |
2204.01998 | Sourendu Gupta | Sourendu Gupta and Rishi Sharma | Parton energy loss at LHC tests for a strongly coupled medium | null | null | null | TIFR/TH/22-16 | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a measure of transverse momentum loss of jets in nuclear
collisions at LHC directly using measurements of jet cross sections in PbPb and
pp collisions. The proposal is shown to be equivalent to R_AA and is equally
straightforward to construct. Using data from the ATLAS collaboration at two
different collision energies, we show that the proposed measure has small
statistical uncertainties. We argue that systematic errors can be easily
improved over our estimates by the experimental collaboration to such an extent
that it directly probes whether the jet-medium interaction is due to a strongly
interacting medium or a weakly interacting plasma. We argue that the current
data may marginally favour a strongly interacting medium. On the other hand,
assuming that the medium is weakly interacting, we are able to provide
estimates of the jet quenching parameter qhat which are in rough agreement with
previously reported estimates.
| [
{
"created": "Tue, 5 Apr 2022 05:42:27 GMT",
"version": "v1"
},
{
"created": "Sun, 10 Apr 2022 12:50:27 GMT",
"version": "v2"
}
] | 2022-04-13 | [
[
"Gupta",
"Sourendu",
""
],
[
"Sharma",
"Rishi",
""
]
] | We construct a measure of transverse momentum loss of jets in nuclear collisions at LHC directly using measurements of jet cross sections in PbPb and pp collisions. The proposal is shown to be equivalent to R_AA and is equally straightforward to construct. Using data from the ATLAS collaboration at two different collision energies, we show that the proposed measure has small statistical uncertainties. We argue that systematic errors can be easily improved over our estimates by the experimental collaboration to such an extent that it directly probes whether the jet-medium interaction is due to a strongly interacting medium or a weakly interacting plasma. We argue that the current data may marginally favour a strongly interacting medium. On the other hand, assuming that the medium is weakly interacting, we are able to provide estimates of the jet quenching parameter qhat which are in rough agreement with previously reported estimates. |
1012.3325 | Zhi-Gang Wang | Zhi-Gang Wang | Analysis of the X(1835) and related baryonium states with Bethe-Salpeter
equation | 13 pages, 2 figures, revise a number | Eur.Phys.J.A47:71,2011 | 10.1140/epja/i2011-11071-x | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we study the mass spectrum of the baryon-antibaryon bound
states $p\bar{p}$, $\Sigma\bar{\Sigma}$, $\Xi\bar{\Xi}$,
$\Lambda\bar{\Lambda}$, $p\bar{N}(1440)$, $\Sigma\bar{\Sigma}(1660)$,
$\Xi\bar{\Xi}^\prime$ and $\Lambda\bar{\Lambda}(1600)$ with the Bethe-Salpeter
equation. The numerical results indicate that the $p\bar{p}$,
$\Sigma\bar{\Sigma}$, $\Xi\bar{\Xi}$, $p\bar{N}(1440)$,
$\Sigma\bar{\Sigma}(1660)$, $\Xi\bar{\Xi}^\prime$ bound states maybe exist, and
the new resonances X(1835) and X(2370) can be tentatively identified as the
$p\bar{p}$ and $p\bar{N}(1440)$ (or $N(1400)\bar{p}$) bound states respectively
with some gluon constituents, and the new resonance X(2120) may be a
pseudoscalar glueball. On the other hand, the Regge trajectory favors
identifying the X(1835), X(2120) and X(2370) as the excited $\eta^\prime(958)$
mesons with the radial quantum numbers $n=3$, 4 and 5, respectively.
| [
{
"created": "Wed, 15 Dec 2010 13:23:01 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Dec 2010 07:45:28 GMT",
"version": "v2"
},
{
"created": "Fri, 11 Feb 2011 13:34:52 GMT",
"version": "v3"
},
{
"created": "Thu, 14 Apr 2011 02:45:47 GMT",
"version": "v4"
},
{
"c... | 2015-03-17 | [
[
"Wang",
"Zhi-Gang",
""
]
] | In this article, we study the mass spectrum of the baryon-antibaryon bound states $p\bar{p}$, $\Sigma\bar{\Sigma}$, $\Xi\bar{\Xi}$, $\Lambda\bar{\Lambda}$, $p\bar{N}(1440)$, $\Sigma\bar{\Sigma}(1660)$, $\Xi\bar{\Xi}^\prime$ and $\Lambda\bar{\Lambda}(1600)$ with the Bethe-Salpeter equation. The numerical results indicate that the $p\bar{p}$, $\Sigma\bar{\Sigma}$, $\Xi\bar{\Xi}$, $p\bar{N}(1440)$, $\Sigma\bar{\Sigma}(1660)$, $\Xi\bar{\Xi}^\prime$ bound states maybe exist, and the new resonances X(1835) and X(2370) can be tentatively identified as the $p\bar{p}$ and $p\bar{N}(1440)$ (or $N(1400)\bar{p}$) bound states respectively with some gluon constituents, and the new resonance X(2120) may be a pseudoscalar glueball. On the other hand, the Regge trajectory favors identifying the X(1835), X(2120) and X(2370) as the excited $\eta^\prime(958)$ mesons with the radial quantum numbers $n=3$, 4 and 5, respectively. |
hep-ph/0005112 | Fredrick Olness | R. Demina, S. Keller, M. Kr\"amer, S. Kretzer, R. Martin, F.I. Olness,
R.J. Scalise, D.E. Soper, W.-K. Tung, N. Varelas, U.K. Yang | Heavy Quark Production and PDF's Subgroup Report | Latex. 8 pages, 7 eps figures. Contribution to the Physics at Run II
Workshops: QCD and Weak Boson Physics | null | null | null | hep-ph | null | We present a status report of a variety of projects related to heavy quark
production and parton distributions for the Tevatron Run II.
| [
{
"created": "Thu, 11 May 2000 19:10:18 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Demina",
"R.",
""
],
[
"Keller",
"S.",
""
],
[
"Krämer",
"M.",
""
],
[
"Kretzer",
"S.",
""
],
[
"Martin",
"R.",
""
],
[
"Olness",
"F. I.",
""
],
[
"Scalise",
"R. J.",
""
],
[
"Soper",
"D. E.",
... | We present a status report of a variety of projects related to heavy quark production and parton distributions for the Tevatron Run II. |
hep-ph/0306114 | Mariusz Sadzikowski | M. Sadzikowski (INP, Cracow) | Superconducting phase transition in the Nambu - Jona-Lasinio model | 7 pages, 3 figures | Mod.Phys.Lett. A16 (2001) 1129-1138 | 10.1142/S0217732301004339 | null | hep-ph | null | The Nambu - Bogoliubov - de Gennes method is applied to the problem of
superconducting QCD. The effective quark-quark interaction is described within
the framework of the Nambu - Jona-Lasinio model. The details of the phase
diagram are given as a function of the strength of the quark-quark coupling
constant $G^{\prime}$. It is find that there is no superconducting phase
transition when one uses the relation between the coupling constants
$G^{\prime}$ and $G$ of the Nambu - Jona-Lasinio model which follows from the
Fierz transformation. However, for other values of $G^{\prime}$ one can find a
rich phase structure containing both the chiral and the superconducting phase
transitions.
| [
{
"created": "Fri, 13 Jun 2003 08:35:06 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Sadzikowski",
"M.",
"",
"INP, Cracow"
]
] | The Nambu - Bogoliubov - de Gennes method is applied to the problem of superconducting QCD. The effective quark-quark interaction is described within the framework of the Nambu - Jona-Lasinio model. The details of the phase diagram are given as a function of the strength of the quark-quark coupling constant $G^{\prime}$. It is find that there is no superconducting phase transition when one uses the relation between the coupling constants $G^{\prime}$ and $G$ of the Nambu - Jona-Lasinio model which follows from the Fierz transformation. However, for other values of $G^{\prime}$ one can find a rich phase structure containing both the chiral and the superconducting phase transitions. |
0805.1905 | Howard Baer | Howard Baer and Xerxes Tata | Dark matter and the LHC | 25 two-column pages with 11 EPS figures. Invited book chapter for
volume on LHC physics to celebrate the Platinum Jubilee of the Indian
National Science Academy, edited by Amitava Datta, Biswarup Mukhopadhyaya and
Amitava Raychaudhuri. Latex file needs style file insa.sty | null | 10.1007/978-81-8489-295-6_12 | null | hep-ph astro-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An abundance of astrophysical evidence indicates that the bulk of matter in
the universe is made up of massive, electrically neutral particles that form
the dark matter (DM). While the density of DM has been precisely measured, the
identity of the DM particle (or particles) is a complete mystery. In fact,
within the laws of physics as we know them (the Standard Model, or SM), none of
the particles have the right properties to make up DM. Remarkably, many new
physics extensions of the SM -- designed to address theoretical issues with the
electroweak symmetry breaking sector -- require the introduction of new
particles, some of which are excellent DM candidates. As the LHC era begins,
there are high hopes that DM particles, along with their associated new matter
states, will be produced in pp collisions. We discuss how LHC experiments,
along with other DM searches, may serve to determine the identity of DM
particles and elucidate the associated physics. Most of our discussion centers
around theories with weak-scale supersymmetry, and allows for several different
DM candidate particles.
| [
{
"created": "Tue, 13 May 2008 18:52:41 GMT",
"version": "v1"
},
{
"created": "Thu, 29 May 2008 17:48:40 GMT",
"version": "v2"
}
] | 2015-05-13 | [
[
"Baer",
"Howard",
""
],
[
"Tata",
"Xerxes",
""
]
] | An abundance of astrophysical evidence indicates that the bulk of matter in the universe is made up of massive, electrically neutral particles that form the dark matter (DM). While the density of DM has been precisely measured, the identity of the DM particle (or particles) is a complete mystery. In fact, within the laws of physics as we know them (the Standard Model, or SM), none of the particles have the right properties to make up DM. Remarkably, many new physics extensions of the SM -- designed to address theoretical issues with the electroweak symmetry breaking sector -- require the introduction of new particles, some of which are excellent DM candidates. As the LHC era begins, there are high hopes that DM particles, along with their associated new matter states, will be produced in pp collisions. We discuss how LHC experiments, along with other DM searches, may serve to determine the identity of DM particles and elucidate the associated physics. Most of our discussion centers around theories with weak-scale supersymmetry, and allows for several different DM candidate particles. |
hep-ph/9310276 | "V. A." Khoze | Torbj\"orn Sj\"ostrand, Valery A. Khoze | Does the W Mass Reconstruction Survive QCD Effects? | 6 pages, CERN Preprint CERN-TH.9043/93, Durham preprint DTP/93/84 | Phys.Rev.Lett.72:28-31,1994 | 10.1103/PhysRevLett.72.28 | null | hep-ph | null | In the hadronic decay mode of a pair of W bosons, $\text{e}~+\text{e}~- \to
\text{W}~+ \text{W}~- \to \text{q}_1 \overline{\text{q}}_2 \text{q}_3
\overline{\text{q}}_4$, QCD interference effects can mix up the two colour
singlets $\text{q}_1 \overline{\text{q}}_2$ and $\text{q}_3
\overline{\text{q}}_4$, i.e. produce hadrons that cannot be uniquely assigned
to either of W$~+$ and W$~-$. We show that interference is negligible for
energetic perturbative gluon emission, and develop models to help us to
estimate the non-perturbative effects. The total contribution to the systematic
error on the W mass reconstruction may be as large as 40 MeV.
| [
{
"created": "Wed, 13 Oct 1993 09:58:00 GMT",
"version": "v1"
}
] | 2011-02-15 | [
[
"Sjöstrand",
"Torbjörn",
""
],
[
"Khoze",
"Valery A.",
""
]
] | In the hadronic decay mode of a pair of W bosons, $\text{e}~+\text{e}~- \to \text{W}~+ \text{W}~- \to \text{q}_1 \overline{\text{q}}_2 \text{q}_3 \overline{\text{q}}_4$, QCD interference effects can mix up the two colour singlets $\text{q}_1 \overline{\text{q}}_2$ and $\text{q}_3 \overline{\text{q}}_4$, i.e. produce hadrons that cannot be uniquely assigned to either of W$~+$ and W$~-$. We show that interference is negligible for energetic perturbative gluon emission, and develop models to help us to estimate the non-perturbative effects. The total contribution to the systematic error on the W mass reconstruction may be as large as 40 MeV. |
1908.05695 | Olga Guadalupe F\'elix-Beltr\'an Dr. | C. Arellano-Celiz, A. Avilez-L\'opez, J. E. Barradas-Guevara, A.
Carrillo-Monteverde, J. L. D\'iaz-Cruz, and O. F\'elix-Beltr\'an | Signatures of Dipolar Dark Matter on Indirect Detection | 20 pages, 6 figures | J. Phys. G: Nucl. Part. Phys. 50 (2023) 015005 (16pp) | 10.1088/1361-6471/aca03d | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we study the annihilation of fermionic dark matter, considering
it as a neutral particle with non-vanishing magnetic ($M$) and electric ($D$)
dipole moments. Effective cross section of the process $\chi \overline{\chi}
\rightarrow \gamma \gamma$ is computed starting from a general form of the
coupling $\chi \overline{\chi} \gamma$ in the framework of an extension of the
Standard Model. By taking into account the annihilation of dark matter pairs
into mono-energetic photons, we found that for masses of $O(10^2)$ GeV, an
electric dipole moment $\sim 10^{-16}\, \textrm{e cm}$ is required to satisfy
the current relic density inferences. Additionally, in order to pin down models
viable to describe the physics of dark matter in the early Universe, we also
constrain our model according to recent measurements of the temperature
anisotropies of the cosmic microwave background radiation, and report
constraints to the electric and magnetic dipole moments for a range of masses
within our model.
| [
{
"created": "Thu, 15 Aug 2019 18:11:07 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Sep 2021 22:55:57 GMT",
"version": "v2"
},
{
"created": "Thu, 13 Apr 2023 14:00:13 GMT",
"version": "v3"
}
] | 2023-04-14 | [
[
"Arellano-Celiz",
"C.",
""
],
[
"Avilez-López",
"A.",
""
],
[
"Barradas-Guevara",
"J. E.",
""
],
[
"Carrillo-Monteverde",
"A.",
""
],
[
"Díaz-Cruz",
"J. L.",
""
],
[
"Félix-Beltrán",
"O.",
""
]
] | In this work we study the annihilation of fermionic dark matter, considering it as a neutral particle with non-vanishing magnetic ($M$) and electric ($D$) dipole moments. Effective cross section of the process $\chi \overline{\chi} \rightarrow \gamma \gamma$ is computed starting from a general form of the coupling $\chi \overline{\chi} \gamma$ in the framework of an extension of the Standard Model. By taking into account the annihilation of dark matter pairs into mono-energetic photons, we found that for masses of $O(10^2)$ GeV, an electric dipole moment $\sim 10^{-16}\, \textrm{e cm}$ is required to satisfy the current relic density inferences. Additionally, in order to pin down models viable to describe the physics of dark matter in the early Universe, we also constrain our model according to recent measurements of the temperature anisotropies of the cosmic microwave background radiation, and report constraints to the electric and magnetic dipole moments for a range of masses within our model. |
1903.00890 | Azad Inshalla oglu Ahmadov | A.I. Ahmadov, C. Aydin, O. Uzun | The inclusive production of charged pion pairs in proton-antiproton
collisions | 26 pages, 16 figures. arXiv admin note: text overlap with
arXiv:hep-ph/9808229 by other authors | Phys. Rev. C 99, 035204 (2019) | 10.1103/PhysRevC.99.035204 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this study, we have considered the contribution of the higher-twist (HT)
effects of the subprocesses to inclusive pion pair production cross section in
the high energy proton-antiproton collisions by using various pion distribution
amplitudes (DAs) within the frozen coupling constant approach and compared them
with the leading-twist contributions. The feature of the HT effects may help
the theoretical interpretation of the future PANDA experiment. The dependencies
of the HT contribution on the transverse momentum $p_T$, the center of mass
energy $\sqrt s$, and the variable $x_T$ are discussed numerically with special
emphasis put on DAs. Moreover, the obtained analytical and numerical results
for the differential cross section of the pion pair production are compared
with the elastic backward scattering of the pion on the proton. We show that
the main contribution to the inclusive cross section comes from the HT direct
production process via gluon-gluon fusion. Also, it is strongly dependent on
the pion DAs, momentum cut-off parameter $\triangle p$ and $<{q_{T}^2}>$ which
is the mean square of the intrinsic momentum of either initial parton.
| [
{
"created": "Sun, 3 Mar 2019 12:33:23 GMT",
"version": "v1"
}
] | 2019-03-27 | [
[
"Ahmadov",
"A. I.",
""
],
[
"Aydin",
"C.",
""
],
[
"Uzun",
"O.",
""
]
] | In this study, we have considered the contribution of the higher-twist (HT) effects of the subprocesses to inclusive pion pair production cross section in the high energy proton-antiproton collisions by using various pion distribution amplitudes (DAs) within the frozen coupling constant approach and compared them with the leading-twist contributions. The feature of the HT effects may help the theoretical interpretation of the future PANDA experiment. The dependencies of the HT contribution on the transverse momentum $p_T$, the center of mass energy $\sqrt s$, and the variable $x_T$ are discussed numerically with special emphasis put on DAs. Moreover, the obtained analytical and numerical results for the differential cross section of the pion pair production are compared with the elastic backward scattering of the pion on the proton. We show that the main contribution to the inclusive cross section comes from the HT direct production process via gluon-gluon fusion. Also, it is strongly dependent on the pion DAs, momentum cut-off parameter $\triangle p$ and $<{q_{T}^2}>$ which is the mean square of the intrinsic momentum of either initial parton. |
hep-ph/9704390 | Dave Sutter | Dave Sutter | The Supersymmetric Flavor Problem and Mu to E Plus Gamma | 52 Pages, Latex; Copy of old thesis submitted to archive | null | null | null | hep-ph | null | The supersymmetric $SU(3)\times SU(2)\times U(1)$ theory with minimal
particle content and general soft supersymmetry breaking terms has 110 physical
parameters in its flavor sector: 30 masses, 39 mixing angles, and 41 phases.
These parameters contain many new measurable sources of flavor violations
unless either the sparticle mass splittings and mixing angles are small or the
sparticle masses are large.
In chapter 1 of this report, we discuss the origins of sparticle mass
splittings and mixing angles in a theory explaining flavor, and we review the
upper limits of sparticle masses that arise from naturalness among the
electroweak breaking parameters. By examining the flavor changing processes
$\mu \to e + \gamma$ and $K^0 - \bar{K}^0$ mixing, we show it is not possible
to simultaneously satisfy the requirements of flavor differentiation among
sparticles and naturalness in electroweak breaking. This indicates that a
crucial ingredient is missing from our understanding of the theory. We discuss
one possible solution in which the messengers that transmit supersymmetry
breaking to ordinary particles are much lighter than $M_{Planck}$.
In our analysis, we found the most important constraint was the process $\mu
\to e + \gamma$. Furthermore, this process is currently being experimentally
investigated. In spite of its importance, the complete branching ratio
calculation has not yet been done. In chapter 2 we present the full one-loop
calculation for $\mu \to e + \gamma$.
| [
{
"created": "Thu, 24 Apr 1997 00:08:01 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Sutter",
"Dave",
""
]
] | The supersymmetric $SU(3)\times SU(2)\times U(1)$ theory with minimal particle content and general soft supersymmetry breaking terms has 110 physical parameters in its flavor sector: 30 masses, 39 mixing angles, and 41 phases. These parameters contain many new measurable sources of flavor violations unless either the sparticle mass splittings and mixing angles are small or the sparticle masses are large. In chapter 1 of this report, we discuss the origins of sparticle mass splittings and mixing angles in a theory explaining flavor, and we review the upper limits of sparticle masses that arise from naturalness among the electroweak breaking parameters. By examining the flavor changing processes $\mu \to e + \gamma$ and $K^0 - \bar{K}^0$ mixing, we show it is not possible to simultaneously satisfy the requirements of flavor differentiation among sparticles and naturalness in electroweak breaking. This indicates that a crucial ingredient is missing from our understanding of the theory. We discuss one possible solution in which the messengers that transmit supersymmetry breaking to ordinary particles are much lighter than $M_{Planck}$. In our analysis, we found the most important constraint was the process $\mu \to e + \gamma$. Furthermore, this process is currently being experimentally investigated. In spite of its importance, the complete branching ratio calculation has not yet been done. In chapter 2 we present the full one-loop calculation for $\mu \to e + \gamma$. |
1710.00184 | Zhi-Long Han | Bin Li, Zhi-Long Han, Yi Liao | Higgs production at future $e^+e^-$ colliders in the Georgi-Machacek
model | 31 pages, 17 figures, published in JHEP | JHEP02(2018)007 | 10.1007/JHEP02(2018)007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study how the dominant single and double SM-like Higgs ($h$) production at
future $e^+e^-$ colliders is modified in the Georgi-Machacek (GM) model. On
imposing theoretical, indirect and direct constraints, significant deviations
of $h$-couplings from their SM values are still possible; for instance, the
Higgs-gauge coupling coupling can be corrected by a factor
$\kappa_{hVV}\in[0.93,1.15]$ in the allowed parameter space. For the
Higgs-strahlung $e^+e^-\to hZ$ and vector boson fusion processes $e^+e^-\to
h\nu\bar{\nu},~he^+e^-$, the cross section could increase by $32\%$ or decrease
by $13\%$. In the case of associated production with a top quark pair
$e^+e^-\to ht\bar{t}$, the cross section can be enhanced up to several times
when the custodial triplet scalar $H_3^0$ is resonantly produced. In the
meanwhile, the double Higgs production $e^+e^-\to hhZ~(hh\nu\bar{\nu})$ can be
maximally enhanced by one order of magnitude at the resonant $H_{1,3}^0$
production. We also include exclusion limits expected from future LHC runs at
higher energy and luminosity and discuss their further constraints on the
relevant model parameters. We find that the GM model can result in likely
measurable deviations of Higgs production from the SM at future $e^+e^-$
colliders.
| [
{
"created": "Sat, 30 Sep 2017 11:49:44 GMT",
"version": "v1"
},
{
"created": "Fri, 2 Feb 2018 01:51:36 GMT",
"version": "v2"
}
] | 2018-03-14 | [
[
"Li",
"Bin",
""
],
[
"Han",
"Zhi-Long",
""
],
[
"Liao",
"Yi",
""
]
] | We study how the dominant single and double SM-like Higgs ($h$) production at future $e^+e^-$ colliders is modified in the Georgi-Machacek (GM) model. On imposing theoretical, indirect and direct constraints, significant deviations of $h$-couplings from their SM values are still possible; for instance, the Higgs-gauge coupling coupling can be corrected by a factor $\kappa_{hVV}\in[0.93,1.15]$ in the allowed parameter space. For the Higgs-strahlung $e^+e^-\to hZ$ and vector boson fusion processes $e^+e^-\to h\nu\bar{\nu},~he^+e^-$, the cross section could increase by $32\%$ or decrease by $13\%$. In the case of associated production with a top quark pair $e^+e^-\to ht\bar{t}$, the cross section can be enhanced up to several times when the custodial triplet scalar $H_3^0$ is resonantly produced. In the meanwhile, the double Higgs production $e^+e^-\to hhZ~(hh\nu\bar{\nu})$ can be maximally enhanced by one order of magnitude at the resonant $H_{1,3}^0$ production. We also include exclusion limits expected from future LHC runs at higher energy and luminosity and discuss their further constraints on the relevant model parameters. We find that the GM model can result in likely measurable deviations of Higgs production from the SM at future $e^+e^-$ colliders. |
0811.0729 | Guy D. Moore | Mark Abraao York, Guy D. Moore | Second order hydrodynamic coefficients from kinetic theory | 31 pages including 3 figures. Corrected for algebraic error which
affected the coefficient lambda_1, which turns out to be positive and about
twice the magnitude previously found | Phys.Rev.D79:054011,2009 | 10.1103/PhysRevD.79.054011 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a relativistic setting, hydrodynamic calculations which include shear
viscosity (which is first order in an expansion in gradients of the flow
velocity) are unstable and acausal unless they also include terms to second
order in gradients. To date such terms have only been computed in
supersymmetric N=4 Super-Yang-Mills theory at infinite coupling. Here we
compute these second-order hydrodynamic coefficients in weakly coupled QCD,
perturbatively to leading order in the QCD coupling, using kinetic theory. We
also compute them in QED and scalar lambda phi^4 theory.
| [
{
"created": "Wed, 5 Nov 2008 13:57:01 GMT",
"version": "v1"
},
{
"created": "Fri, 6 Feb 2009 13:25:20 GMT",
"version": "v2"
}
] | 2009-07-29 | [
[
"York",
"Mark Abraao",
""
],
[
"Moore",
"Guy D.",
""
]
] | In a relativistic setting, hydrodynamic calculations which include shear viscosity (which is first order in an expansion in gradients of the flow velocity) are unstable and acausal unless they also include terms to second order in gradients. To date such terms have only been computed in supersymmetric N=4 Super-Yang-Mills theory at infinite coupling. Here we compute these second-order hydrodynamic coefficients in weakly coupled QCD, perturbatively to leading order in the QCD coupling, using kinetic theory. We also compute them in QED and scalar lambda phi^4 theory. |
1109.3513 | Randy Lewis | Randy Lewis, Claudio Pica, Francesco Sannino | Light Asymmetric Dark Matter on the Lattice: SU(2) Technicolor with Two
Fundamental Flavors | 22 pages, 8 figures, published version | Phys.Rev.D85:014504,2012 | 10.1103/PhysRevD.85.014504 | CP3-Origins-2011-28, DIAS-2011-15 | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The SU(2) gauge theory with two massless Dirac flavors constitutes the
building block of several models of Technicolor. Furthermore it has also been
used as a template for the construction of a natural light asymmetric, or mixed
type, dark matter candidate. We use explicit lattice simulations to confirm the
pattern of chiral symmetry breaking by determining the Goldstone spectrum and
therefore show that the dark matter candidate can, de facto, be constituted by
a complex Goldstone boson. We also determine the phenomenologically relevant
spin-one and spin-zero isovector spectrum and demonstrate that it is well
separated from the Goldstone spectrum.
| [
{
"created": "Fri, 16 Sep 2011 01:45:56 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Jan 2012 19:07:36 GMT",
"version": "v2"
}
] | 2013-05-30 | [
[
"Lewis",
"Randy",
""
],
[
"Pica",
"Claudio",
""
],
[
"Sannino",
"Francesco",
""
]
] | The SU(2) gauge theory with two massless Dirac flavors constitutes the building block of several models of Technicolor. Furthermore it has also been used as a template for the construction of a natural light asymmetric, or mixed type, dark matter candidate. We use explicit lattice simulations to confirm the pattern of chiral symmetry breaking by determining the Goldstone spectrum and therefore show that the dark matter candidate can, de facto, be constituted by a complex Goldstone boson. We also determine the phenomenologically relevant spin-one and spin-zero isovector spectrum and demonstrate that it is well separated from the Goldstone spectrum. |
1609.08994 | Dimitri Bourilkov | Dimitri Bourilkov | Exploring the LHC Landscape with Dileptons | 25 pages, 2 tables, 13 figures, LaTeX; expanded the results with the
new LUXqed_plus_PDF4LHC15 photon PDF set to include the dielectron channel | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The dilepton decay channels provide clean signatures and are an ideal hunting
ground for high mass resonant, like Z', or non-resonant, like contact
interactions or extra dimensions, searches at the LHC. The production of high
invariant mass opposite sign lepton pairs in proton-proton collisions in the
Standard Model is dominated by the Drell-Yan process. In addition to this
photon or Z exchange mediated mechanism, photons radiated by the incoming
protons can collide and produce lepton pairs. In this paper detailed
calculations of the Drell-Yan process at next-to-next-to-leading order in QCD
and next-to-leading order in the electroweak corrections, augmented with the
photon-induced effects, are presented in the typical acceptance of a
multi-purpose LHC detector at center of mass energy 13 TeV. Estimates of the
expected backgrounds for new physics searches are provided for dilepton
invariant masses up to the LHC kinematic limit.
| [
{
"created": "Wed, 28 Sep 2016 16:29:55 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Oct 2016 15:19:19 GMT",
"version": "v2"
},
{
"created": "Fri, 20 Jan 2017 23:56:55 GMT",
"version": "v3"
}
] | 2017-01-24 | [
[
"Bourilkov",
"Dimitri",
""
]
] | The dilepton decay channels provide clean signatures and are an ideal hunting ground for high mass resonant, like Z', or non-resonant, like contact interactions or extra dimensions, searches at the LHC. The production of high invariant mass opposite sign lepton pairs in proton-proton collisions in the Standard Model is dominated by the Drell-Yan process. In addition to this photon or Z exchange mediated mechanism, photons radiated by the incoming protons can collide and produce lepton pairs. In this paper detailed calculations of the Drell-Yan process at next-to-next-to-leading order in QCD and next-to-leading order in the electroweak corrections, augmented with the photon-induced effects, are presented in the typical acceptance of a multi-purpose LHC detector at center of mass energy 13 TeV. Estimates of the expected backgrounds for new physics searches are provided for dilepton invariant masses up to the LHC kinematic limit. |
1110.1119 | Kazuki Sakurai | B. C. Allanach, T. J. Khoo, K. Sakurai | Interpreting a 1 fb^-1 ATLAS Search in the Minimal Anomaly Mediated
Supersymmetry Breaking Model | 18 pages, 11 figures | null | 10.1007/JHEP11(2011)132 | DAMTP-2011-83 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent LHC data significantly extend the exclusion limits for supersymmetric
particles, particularly in the jets plus missing transverse momentum channels.
The most recent such data have so far been interpreted by the experiment in
only two different supersymmetry breaking models: the constrained minimal
supersymmetric standard model (CMSSM) and a simplified model with only squarks
and gluinos and massless neutralinos. We compare kinematical distributions of
supersymmetric signal events predicted by the CMSSM and anomaly mediated
supersymmetry breaking (mAMSB) before calculating exclusion limits in mAMSB. We
obtain a lower limit of 900 GeV on squark and gluino masses at the 95%
confidence level for the equal mass limit, tan(beta)=10 and mu>0.
| [
{
"created": "Wed, 5 Oct 2011 23:41:08 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Oct 2011 23:44:36 GMT",
"version": "v2"
},
{
"created": "Wed, 30 Nov 2011 10:34:38 GMT",
"version": "v3"
}
] | 2015-05-30 | [
[
"Allanach",
"B. C.",
""
],
[
"Khoo",
"T. J.",
""
],
[
"Sakurai",
"K.",
""
]
] | Recent LHC data significantly extend the exclusion limits for supersymmetric particles, particularly in the jets plus missing transverse momentum channels. The most recent such data have so far been interpreted by the experiment in only two different supersymmetry breaking models: the constrained minimal supersymmetric standard model (CMSSM) and a simplified model with only squarks and gluinos and massless neutralinos. We compare kinematical distributions of supersymmetric signal events predicted by the CMSSM and anomaly mediated supersymmetry breaking (mAMSB) before calculating exclusion limits in mAMSB. We obtain a lower limit of 900 GeV on squark and gluino masses at the 95% confidence level for the equal mass limit, tan(beta)=10 and mu>0. |
0705.3049 | Misha Stephanov | M.A. Stephanov | Deconstruction of Unparticles | 5 pages | Phys.Rev.D76:035008,2007 | 10.1103/PhysRevD.76.035008 | null | hep-ph | null | We discuss properties of hypothetical scale invariant (unparticle) matter by
viewing it as a tower of massive particles. We show how peculiar properties of
unparticles emerge in the limit when the mass spacing parameter Delta vanishes.
We explain why unparticle cannot decay in this limit and how, for finite Delta,
the decays manifest themselves in a relation between the reconstructed
invariant mass and vertex displacement. We describe a model field theory in
AdS5 which explicitly implements the deconstruction procedure by truncating the
extra dimension to size of order 1/Delta.
| [
{
"created": "Tue, 22 May 2007 19:52:48 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Stephanov",
"M. A.",
""
]
] | We discuss properties of hypothetical scale invariant (unparticle) matter by viewing it as a tower of massive particles. We show how peculiar properties of unparticles emerge in the limit when the mass spacing parameter Delta vanishes. We explain why unparticle cannot decay in this limit and how, for finite Delta, the decays manifest themselves in a relation between the reconstructed invariant mass and vertex displacement. We describe a model field theory in AdS5 which explicitly implements the deconstruction procedure by truncating the extra dimension to size of order 1/Delta. |
1405.5204 | Sam McDermott | Asher Berlin, Pierre Gratia, Dan Hooper, Samuel D. McDermott | Hidden Sector Dark Matter Models for the Galactic Center Gamma-Ray
Excess | 11 pages, 8 figures; v2: added discussion of AMS positron
constraints; v3: matches journal version | Phys. Rev. D 90, 015032 (2014) | 10.1103/PhysRevD.90.015032 | FERMILAB-PUB-14-134-A, MCTP-14-12 | hep-ph astro-ph.CO astro-ph.GA astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The gamma-ray excess observed from the Galactic Center can be interpreted as
dark matter particles annihilating into Standard Model fermions with a cross
section near that expected for a thermal relic. Although many particle physics
models have been shown to be able to account for this signal, the fact that
this particle has not yet been observed in direct detection experiments
somewhat restricts the nature of its interactions. One way to suppress the dark
matter's elastic scattering cross section with nuclei is to consider models in
which the dark matter is part of a hidden sector. In such models, the dark
matter can annihilate into other hidden sector particles, which then decay into
Standard Model fermions through a small degree of mixing with the photon, Z, or
Higgs bosons. After discussing the gamma-ray signal from hidden sector dark
matter in general terms, we consider two concrete realizations: a hidden photon
model in which the dark matter annihilates into a pair of vector gauge bosons
that decay through kinetic mixing with the photon, and a scenario within the
generalized NMSSM in which the dark matter is a singlino-like neutralino that
annihilates into a pair of singlet Higgs bosons, which decay through their
mixing with the Higgs bosons of the MSSM.
| [
{
"created": "Tue, 20 May 2014 19:49:45 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Jun 2014 21:25:19 GMT",
"version": "v2"
},
{
"created": "Mon, 18 Aug 2014 15:19:31 GMT",
"version": "v3"
}
] | 2014-08-19 | [
[
"Berlin",
"Asher",
""
],
[
"Gratia",
"Pierre",
""
],
[
"Hooper",
"Dan",
""
],
[
"McDermott",
"Samuel D.",
""
]
] | The gamma-ray excess observed from the Galactic Center can be interpreted as dark matter particles annihilating into Standard Model fermions with a cross section near that expected for a thermal relic. Although many particle physics models have been shown to be able to account for this signal, the fact that this particle has not yet been observed in direct detection experiments somewhat restricts the nature of its interactions. One way to suppress the dark matter's elastic scattering cross section with nuclei is to consider models in which the dark matter is part of a hidden sector. In such models, the dark matter can annihilate into other hidden sector particles, which then decay into Standard Model fermions through a small degree of mixing with the photon, Z, or Higgs bosons. After discussing the gamma-ray signal from hidden sector dark matter in general terms, we consider two concrete realizations: a hidden photon model in which the dark matter annihilates into a pair of vector gauge bosons that decay through kinetic mixing with the photon, and a scenario within the generalized NMSSM in which the dark matter is a singlino-like neutralino that annihilates into a pair of singlet Higgs bosons, which decay through their mixing with the Higgs bosons of the MSSM. |
1708.01061 | Lisa Olbrich | Lisa Olbrich, Mikl\'os Z\'et\'enyi, Francesco Giacosa, and Dirk H.
Rischke | Influence of the axial anomaly on the decay $N(1535) \rightarrow N\eta $ | 14 pages, 4 figures, to appear in Phys. Rev. D | Phys. Rev. D 97, 014007 (2018) | 10.1103/PhysRevD.97.014007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The decay width of $N(1535)\rightarrow N\eta$ is as large as that of
$N(1535)\rightarrow N\pi$. This is in evident conflict with simple expectations
based on flavor symmetry and phase space. Similarly, the decay width of
$\Lambda(1670) \rightarrow \Lambda(1116) \eta $ is larger than predicted by
flavor symmetry. In this work, we propose that the axial $U(1)_{A}$ anomaly is
responsible for an enhanced coupling of (some) excited baryons to the $\eta$
meson. We test this idea by including a new, chirally symmetric but $U(1)_{A}$
anomalous, term in an effective hadronic model decribing baryons and their
chiral partners in the mirror assignment. This term enhances the decay of the
chiral partners into baryons and an $\eta$ meson, such as $N(1535)\rightarrow
N\eta$. Moreover, a strong coupling of $N(1535)$ to $N \eta^\prime $ emerges
(this is important for studies of $\eta^\prime$ production processes). Our
approach shows that $N(1535)$ is predominantly the chiral partner of $N(939)$,
and $\Lambda(1670)$ the chiral partner of $\Lambda(1116)$. Finally, our
formalism can be used to couple the pseudoscalar glueball $\tilde{G}$ to
baryons. We expect a large cross section for the reaction $\bar{p}p \rightarrow
\tilde{G} \rightarrow \bar{p}p(1535)$, which can be experimentally tested in
the future PANDA experiment.
| [
{
"created": "Thu, 3 Aug 2017 09:09:03 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Dec 2017 08:02:50 GMT",
"version": "v2"
}
] | 2018-01-24 | [
[
"Olbrich",
"Lisa",
""
],
[
"Zétényi",
"Miklós",
""
],
[
"Giacosa",
"Francesco",
""
],
[
"Rischke",
"Dirk H.",
""
]
] | The decay width of $N(1535)\rightarrow N\eta$ is as large as that of $N(1535)\rightarrow N\pi$. This is in evident conflict with simple expectations based on flavor symmetry and phase space. Similarly, the decay width of $\Lambda(1670) \rightarrow \Lambda(1116) \eta $ is larger than predicted by flavor symmetry. In this work, we propose that the axial $U(1)_{A}$ anomaly is responsible for an enhanced coupling of (some) excited baryons to the $\eta$ meson. We test this idea by including a new, chirally symmetric but $U(1)_{A}$ anomalous, term in an effective hadronic model decribing baryons and their chiral partners in the mirror assignment. This term enhances the decay of the chiral partners into baryons and an $\eta$ meson, such as $N(1535)\rightarrow N\eta$. Moreover, a strong coupling of $N(1535)$ to $N \eta^\prime $ emerges (this is important for studies of $\eta^\prime$ production processes). Our approach shows that $N(1535)$ is predominantly the chiral partner of $N(939)$, and $\Lambda(1670)$ the chiral partner of $\Lambda(1116)$. Finally, our formalism can be used to couple the pseudoscalar glueball $\tilde{G}$ to baryons. We expect a large cross section for the reaction $\bar{p}p \rightarrow \tilde{G} \rightarrow \bar{p}p(1535)$, which can be experimentally tested in the future PANDA experiment. |
0912.3427 | Filipe Joaquim | F. R. Joaquim | Running effects on neutrino parameters and l_i -> l_j gamma predictions
in the triplet-extended MSSM | 36 pages, 8 figures. References added and structure modified. Results
unchanged. Final version to appear in JHEP | JHEP 1006:079,2010 | 10.1007/JHEP06(2010)079 | CERN-PH-TH/2009-244 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the renormalisation group effects induced on neutrino mass and
mixing parameters in a triplet-extended minimal supersymmetric standard model
where a vector-like pair of hypercharge $\pm 1$ triplet superfields is added.
We first rederive the one-loop renormalisation group equation for the effective
neutrino mass operator and, for the case in which this operator originates
solely from the decoupling of the triplets, the corresponding equations for
neutrino masses, mixing parameters and CP-violating phases. We compare our
results with the ones obtained previously, and quantify the importance of the
RG induced corrections to neutrino observables by means of numerical examples.
In the second part of the paper, we study the correlation of the model's
predictions for the lepton flavour violating processes $\ell_i \rightarrow
\ell_j \gamma$ with the measured neutrino mass squared differences and mixing
angles. We also emphasize the r\^ole played by the unknown reactor neutrino
mixing angle $\theta_{13}$ and the Dirac CP-violating phase $\delta$. We point
out that, if $\tan\beta$ is large, the results obtained in the commonly made
approximations may deviate significantly from the ones following from solving
numerically the relevant set of renormalisation group equations and using the
exact one-loop formulae for the decay rates.
| [
{
"created": "Thu, 17 Dec 2009 15:09:13 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Jun 2010 13:49:59 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Joaquim",
"F. R.",
""
]
] | We investigate the renormalisation group effects induced on neutrino mass and mixing parameters in a triplet-extended minimal supersymmetric standard model where a vector-like pair of hypercharge $\pm 1$ triplet superfields is added. We first rederive the one-loop renormalisation group equation for the effective neutrino mass operator and, for the case in which this operator originates solely from the decoupling of the triplets, the corresponding equations for neutrino masses, mixing parameters and CP-violating phases. We compare our results with the ones obtained previously, and quantify the importance of the RG induced corrections to neutrino observables by means of numerical examples. In the second part of the paper, we study the correlation of the model's predictions for the lepton flavour violating processes $\ell_i \rightarrow \ell_j \gamma$ with the measured neutrino mass squared differences and mixing angles. We also emphasize the r\^ole played by the unknown reactor neutrino mixing angle $\theta_{13}$ and the Dirac CP-violating phase $\delta$. We point out that, if $\tan\beta$ is large, the results obtained in the commonly made approximations may deviate significantly from the ones following from solving numerically the relevant set of renormalisation group equations and using the exact one-loop formulae for the decay rates. |
1007.3923 | Junko Yamagata-Sekihara | J. Yamagata-Sekihara, J. Nieves and E. Oset | Couplings in coupled channels versus wave functions in the case of
resonances: application to the two $\Lambda(1405)$ states | 23 pages, 3 figures. v2: Added a section to calculate form factors | Phys.Rev.D83:014003,2011 | 10.1103/PhysRevD.83.014003 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we develop a formalism to evaluate wave functions in momentum
and coordinate space for the resonant states dynamically generated in a unitary
coupled channel approach. The on shell approach for the scattering matrix,
commonly used, is also obtained in Quantum Mechanics with a separable
potential, which allows one to write wave functions in a trivial way. We
develop useful relationships among the couplings of the dynamically generated
resonances to the different channels and the wave functions at the origin. The
formalism provides an intuitive picture of the resonances in the coupled
channel approach, as bound states of one bound channel, which decays into open
ones. It also provides an insight and practical rules for evaluating couplings
of the resonances to external sources and how to deal with final state
interaction in production processes. As an application of the formalism we
evaluate the wave functions of the two $\Lambda(1405)$ states in the $\pi
\Sigma$, $\bar{K} N$ and other coupled channels.
| [
{
"created": "Thu, 22 Jul 2010 15:57:13 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Jan 2011 12:46:00 GMT",
"version": "v2"
}
] | 2011-01-28 | [
[
"Yamagata-Sekihara",
"J.",
""
],
[
"Nieves",
"J.",
""
],
[
"Oset",
"E.",
""
]
] | In this paper we develop a formalism to evaluate wave functions in momentum and coordinate space for the resonant states dynamically generated in a unitary coupled channel approach. The on shell approach for the scattering matrix, commonly used, is also obtained in Quantum Mechanics with a separable potential, which allows one to write wave functions in a trivial way. We develop useful relationships among the couplings of the dynamically generated resonances to the different channels and the wave functions at the origin. The formalism provides an intuitive picture of the resonances in the coupled channel approach, as bound states of one bound channel, which decays into open ones. It also provides an insight and practical rules for evaluating couplings of the resonances to external sources and how to deal with final state interaction in production processes. As an application of the formalism we evaluate the wave functions of the two $\Lambda(1405)$ states in the $\pi \Sigma$, $\bar{K} N$ and other coupled channels. |
hep-ph/0607110 | Nilmani Mathur | Nilmani Mathur, A. Alexandru, Y. Chen, S.J. Dong, T. Draper,
I.Horvath, F.X. Lee, K.F. Liu, S. Tamhankar, and J.B. Zhang | Scalar Mesons a0(1450) and sigma(600) from Lattice QCD | 11 pages, 9 figures, accepted for publication in Phys. Rev. D | Phys.Rev.D76:114505,2007 | 10.1103/PhysRevD.76.114505 | JLAB-THY-06-511, UK/06-06 | hep-ph hep-lat nucl-th | null | We study the a0 and sigma mesons with the overlap fermion in the chiral
regime with the pion mass as low as 182 MeV in the quenched approximation.
After the eta'pi ghost states are separated, we find that the a0 mass with
q\bar{q} interpolation field to be almost independent of the quark mass in the
region below the strange quark mass. The chirally extrapolated results are
consistent with a0(1450) being the u\bar{d} meson and K0*(1430) being the
u\bar{s} meson with calculated masses at 1.42+_0.13 GeV and 1.41+_ 0.12 GeV
respectively. We also calculate the scalar mesonium with a tetraquark
interpolation field. In addition to the two pion scattering states, we find a
state at around 550 MeV. Through the study of volume dependence, we confirm
that this state is a one-particle state, in contrast to the two-pion scattering
states. This suggests that the observed state is a tetraquark mesonium which is
quite possibly the sigma(600) meson.
| [
{
"created": "Mon, 10 Jul 2006 20:04:31 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Oct 2007 13:29:34 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Mathur",
"Nilmani",
""
],
[
"Alexandru",
"A.",
""
],
[
"Chen",
"Y.",
""
],
[
"Dong",
"S. J.",
""
],
[
"Draper",
"T.",
""
],
[
"Horvath",
"I.",
""
],
[
"Lee",
"F. X.",
""
],
[
"Liu",
"K. F.",
... | We study the a0 and sigma mesons with the overlap fermion in the chiral regime with the pion mass as low as 182 MeV in the quenched approximation. After the eta'pi ghost states are separated, we find that the a0 mass with q\bar{q} interpolation field to be almost independent of the quark mass in the region below the strange quark mass. The chirally extrapolated results are consistent with a0(1450) being the u\bar{d} meson and K0*(1430) being the u\bar{s} meson with calculated masses at 1.42+_0.13 GeV and 1.41+_ 0.12 GeV respectively. We also calculate the scalar mesonium with a tetraquark interpolation field. In addition to the two pion scattering states, we find a state at around 550 MeV. Through the study of volume dependence, we confirm that this state is a one-particle state, in contrast to the two-pion scattering states. This suggests that the observed state is a tetraquark mesonium which is quite possibly the sigma(600) meson. |
hep-ph/0510105 | Bumseok Kyae | Bumseok Kyae, and Qaisar Shafi | Flipped SU(5) Predicts $\delta T/T$ | 1+15 pages, 6 figures, version to appear in Phys. Lett. B | Phys.Lett.B635:247-252,2006 | 10.1016/j.physletb.2006.03.007 | BA-05-102, KIAS-P05054 | hep-ph astro-ph | null | We discuss hybrid inflation in supersymmetric flipped SU(5) model such that
the cosmic microwave anisotropy $\delta T/T$ is essentially proportional to $(M
/M_{P})^2$, where $M$ denotes the symmetry breaking scale and $M_{P}$
($=2.4\times 10^{18}$ GeV) is the reduced Planck mass. The magnitude of $M$
determined from $\delta T/T$ measurements can be consistent with the value
inferred from the evolution of SU(3) and SU(2) gauge couplings. In other words,
one could state that flipped SU(5) predicts (more precisely `postdicts')
$\delta T/T$. The scalar spectral index $n_s = 0.993\pm 0.007$, the scalar to
tensor ratio satisfies $r \lapproxeq 10^{-6}$, while $dn_s/d{\rm ln}k
\lapproxeq 4\times 10^{-4}$.
| [
{
"created": "Sat, 8 Oct 2005 07:09:05 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Mar 2006 15:38:00 GMT",
"version": "v2"
}
] | 2011-05-12 | [
[
"Kyae",
"Bumseok",
""
],
[
"Shafi",
"Qaisar",
""
]
] | We discuss hybrid inflation in supersymmetric flipped SU(5) model such that the cosmic microwave anisotropy $\delta T/T$ is essentially proportional to $(M /M_{P})^2$, where $M$ denotes the symmetry breaking scale and $M_{P}$ ($=2.4\times 10^{18}$ GeV) is the reduced Planck mass. The magnitude of $M$ determined from $\delta T/T$ measurements can be consistent with the value inferred from the evolution of SU(3) and SU(2) gauge couplings. In other words, one could state that flipped SU(5) predicts (more precisely `postdicts') $\delta T/T$. The scalar spectral index $n_s = 0.993\pm 0.007$, the scalar to tensor ratio satisfies $r \lapproxeq 10^{-6}$, while $dn_s/d{\rm ln}k \lapproxeq 4\times 10^{-4}$. |
0805.2469 | Bin Gong | Bin Gong and Jian-Xiong Wang | QCD corrections to polarization of J/\psi and \Upsilon at Fermilab
Tevatron and CERN LHC | 12 pages, 12 figures, two columns, use revtex4; to appear in PRD | Phys.Rev.D78:074011,2008 | 10.1103/PhysRevD.78.074011 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we present more detail of the calculation on the NLO QCD
corrections to polarization of direct J/psi production via color singlet at
Tevatron and LHC, as well as the results for Upsilon for the first time. Our
results show that the J/psi polarization status drastically changes from
transverse polarization dominant at LO into longitudinal polarization dominant
in the whole range of the transverse momentum $p_t$ of J/psi when the NLO
corrections are counted. For Upsilon production, the p_t distribution of the
polarization status behaves almost the same as that for J/psi except that the
NLO result is transverse polarization at small p_t range. Although the
theoretical evaluation predicts a larger longitudinal polarization than the
measured value at Tevatron, it may provide a solution towards the previous
large discrepancy for J/psi and Upsilon polarization between theoretical
predication and experimental measurement, and suggests that the next important
step is to calculate the NLO corrections to hadronproduction of color octet
state J/psi^(8) and Upsilon^(8). Our calculations are performed in two ways,
namely we do and do not analytically sum over the polarizations, and then check
them with each other.
| [
{
"created": "Fri, 16 May 2008 09:21:26 GMT",
"version": "v1"
},
{
"created": "Tue, 20 May 2008 02:40:29 GMT",
"version": "v2"
},
{
"created": "Wed, 21 May 2008 08:08:41 GMT",
"version": "v3"
},
{
"created": "Mon, 29 Sep 2008 06:12:19 GMT",
"version": "v4"
}
] | 2009-01-14 | [
[
"Gong",
"Bin",
""
],
[
"Wang",
"Jian-Xiong",
""
]
] | In this work, we present more detail of the calculation on the NLO QCD corrections to polarization of direct J/psi production via color singlet at Tevatron and LHC, as well as the results for Upsilon for the first time. Our results show that the J/psi polarization status drastically changes from transverse polarization dominant at LO into longitudinal polarization dominant in the whole range of the transverse momentum $p_t$ of J/psi when the NLO corrections are counted. For Upsilon production, the p_t distribution of the polarization status behaves almost the same as that for J/psi except that the NLO result is transverse polarization at small p_t range. Although the theoretical evaluation predicts a larger longitudinal polarization than the measured value at Tevatron, it may provide a solution towards the previous large discrepancy for J/psi and Upsilon polarization between theoretical predication and experimental measurement, and suggests that the next important step is to calculate the NLO corrections to hadronproduction of color octet state J/psi^(8) and Upsilon^(8). Our calculations are performed in two ways, namely we do and do not analytically sum over the polarizations, and then check them with each other. |
2105.04345 | Michael Klasen | V. Guzey, M. Klasen | Prospects for diffractive dijet photoproduction at the EIC | 5 pages, 4 figures | null | null | MS-TP-21-20 | hep-ph hep-ex nucl-ex | http://creativecommons.org/licenses/by/4.0/ | We discuss the prospects of diffractive dijet photoproduction at the EIC to
distinguish different fits of diffractive proton PDFs, different schemes of
factorization breaking, to determine diffractive nuclear PDFs and pion PDFs
from leading neutron production.
| [
{
"created": "Mon, 10 May 2021 13:23:35 GMT",
"version": "v1"
}
] | 2021-05-11 | [
[
"Guzey",
"V.",
""
],
[
"Klasen",
"M.",
""
]
] | We discuss the prospects of diffractive dijet photoproduction at the EIC to distinguish different fits of diffractive proton PDFs, different schemes of factorization breaking, to determine diffractive nuclear PDFs and pion PDFs from leading neutron production. |
hep-ph/9709373 | Piotr Chankowski | Wojciech Krolikowski (Inst. of. Theor. Phys., Warsaw University) | Texture dynamics for neutrinos | 22 pages, TeX, no special macros needed | Acta Phys.Polon. B29 (1998) 629-650 | null | IFT-UW/97-15 | hep-ph | null | An ansatz for mass matrix was recently proposed for charged leptons,
predicting (in its diagonal approximation) $m_\tau\simeq1776.80$ MeV from the
experimental values of $m_e$ and $m_\mu$, in agreement with $m_\tau^{exp}=
1777.00^{+0.30}_{-0.27}$ MeV. Now it is applied to neutrinos. If the amplitude
of neutrino oscillations $\nu_\mu\to\nu_\tau$ is $\sim 1/2$ and
$|m^2_{\nu_\tau}-m^2_{\nu_\mu}|\sim(0.0003 to 0.01) eV^2$, as seems to follow
from atmospheric-neutrino experiments, this ansatz predicts $m_{\nu_e}\ll
m_{\nu_\mu}\sim(0.2 to 1)\times 10^{-2} $ eV and $m_{\nu_\tau}\sim(0.2 to
1)\times 10^{-1} eV$, and also the amplitude of neutrino oscillations $\nu_e
\to \nu_\mu \sim 2^{+4}_{-2}\times 10^{-4}$ (in the vacuum). Such a very small
amplitude for $\nu_e \to \nu_\mu $ is implied by the value of $ m_\tau^{exp} -
1776.80 $ MeV used to determine the deviation of the diagonalizing matrix
$\hat{U}^{(e)}$ from $\hat{1}$ in the lepton Cabibbo-Kobayashi- Maskawa matrix
$\hat{V} = \hat{U}^{(\nu) \dagger}\hat{U}^{(e)}$. Here, $\hat{U}^{(\nu)}$ by
itself gives practically no oscillations $\nu_e \to\nu_\mu$, while it provides
the large oscillations $\nu_\mu \to\nu_\tau$.
| [
{
"created": "Wed, 17 Sep 1997 10:22:41 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Krolikowski",
"Wojciech",
"",
"Inst. of. Theor. Phys., Warsaw University"
]
] | An ansatz for mass matrix was recently proposed for charged leptons, predicting (in its diagonal approximation) $m_\tau\simeq1776.80$ MeV from the experimental values of $m_e$ and $m_\mu$, in agreement with $m_\tau^{exp}= 1777.00^{+0.30}_{-0.27}$ MeV. Now it is applied to neutrinos. If the amplitude of neutrino oscillations $\nu_\mu\to\nu_\tau$ is $\sim 1/2$ and $|m^2_{\nu_\tau}-m^2_{\nu_\mu}|\sim(0.0003 to 0.01) eV^2$, as seems to follow from atmospheric-neutrino experiments, this ansatz predicts $m_{\nu_e}\ll m_{\nu_\mu}\sim(0.2 to 1)\times 10^{-2} $ eV and $m_{\nu_\tau}\sim(0.2 to 1)\times 10^{-1} eV$, and also the amplitude of neutrino oscillations $\nu_e \to \nu_\mu \sim 2^{+4}_{-2}\times 10^{-4}$ (in the vacuum). Such a very small amplitude for $\nu_e \to \nu_\mu $ is implied by the value of $ m_\tau^{exp} - 1776.80 $ MeV used to determine the deviation of the diagonalizing matrix $\hat{U}^{(e)}$ from $\hat{1}$ in the lepton Cabibbo-Kobayashi- Maskawa matrix $\hat{V} = \hat{U}^{(\nu) \dagger}\hat{U}^{(e)}$. Here, $\hat{U}^{(\nu)}$ by itself gives practically no oscillations $\nu_e \to\nu_\mu$, while it provides the large oscillations $\nu_\mu \to\nu_\tau$. |
hep-ph/9501286 | Markus Finkemeier | Markus Finkemeier (Harvard University) | Radiative Corrections to $\pi_{l2}$ and $K_{l2}$ Decays | 8 pages, Latex, uses epsfig. Revised version: Major changes in the
presentaion, but no changes in the results. To appear in Phys. Lett. B | null | null | HUTP-96/A027 | hep-ph | null | We reexamine radiative corrections to $\pi_{l2}$ and $K_{l2}$ decays. We
perform a matching calculation, including vector and axial vector resonances as
explicit degrees of freedom in the long distance part. By considering the
dependence on the matching scale and on the hadronic parameters, and by
comparing with model independent estimates, we scrutinize the model dependence
of the results. For the pseudoscalar meson decay constants, we extract the
values f_pi = (92.1 \pm 0.3) MeV and f_K = (112.4 \pm 0.9) MeV. For the ratios
R_pi and R_K of the electronic and muonic decay modes, we predict R_pi =
(1.2354 \pm 0.0002) 10^{-4} and R_K = (2.472 \pm 0.001) 10^{-5}.
| [
{
"created": "Thu, 12 Jan 1995 15:19:32 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Sep 1996 20:29:53 GMT",
"version": "v2"
}
] | 2016-09-01 | [
[
"Finkemeier",
"Markus",
"",
"Harvard University"
]
] | We reexamine radiative corrections to $\pi_{l2}$ and $K_{l2}$ decays. We perform a matching calculation, including vector and axial vector resonances as explicit degrees of freedom in the long distance part. By considering the dependence on the matching scale and on the hadronic parameters, and by comparing with model independent estimates, we scrutinize the model dependence of the results. For the pseudoscalar meson decay constants, we extract the values f_pi = (92.1 \pm 0.3) MeV and f_K = (112.4 \pm 0.9) MeV. For the ratios R_pi and R_K of the electronic and muonic decay modes, we predict R_pi = (1.2354 \pm 0.0002) 10^{-4} and R_K = (2.472 \pm 0.001) 10^{-5}. |
1401.3739 | Moira Gresham | Moira I. Gresham and Kathryn M. Zurek | On the Effect of Nuclear Response Functions in Dark Matter Direct
Detection | 42 pages, 12 figures, 5 tables | Phys. Rev. D 89, 123521 (2014) | 10.1103/PhysRevD.89.123521 | MCTP-14-01 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the effect of nuclear response functions, as laid out in
[Fitzpatrick et al, arXiv:1203.3542], on dark matter (DM) direct detection in
the context of well-motivated UV completions, including electric and magnetic
dipoles, anapole, spin-orbit, and pseudoscalar-mediated DM. Together, these
encompass five of the six nuclear responses extracted from the non-relativistic
effective theory of [Fitzpatrick et al, arXiv:1203.3542] (with the sixth
difficult to UV complete), with two of the six combinations corresponding to
standard spin-independent and -dependent responses. For constraints from
existing direct detection experiments, we find that only the COUPP constraint,
due to its heavy iodine target with large angular momentum and an unpaired
spin, and its large energy range sensitivity, is substantially modified by the
new responses compared to what would be inferred using the standard form
factors to model the energy dependence of the response. For heavy targets such
as xenon and germanium, the behavior of the new nuclear responses as recoil
energy increases can be substantially different than that of the standard
responses, but this has almost no impact on the constraints derived from
experiments such as LUX, XENON100 and CDMS since the maximum nuclear recoil
energy detected in these experiments is relatively low. We simulate mock data
for 80 and 250 GeV DM candidates utilizing the new nuclear responses to
highlight how they might affect a putative signal, and find the new responses
are most important for momentum-suppressed interactions such as the magnetic
dipole or pseudoscalar-mediated interaction when the target is relatively heavy
(such as xenon and iodine).
| [
{
"created": "Wed, 15 Jan 2014 20:59:04 GMT",
"version": "v1"
}
] | 2014-07-02 | [
[
"Gresham",
"Moira I.",
""
],
[
"Zurek",
"Kathryn M.",
""
]
] | We examine the effect of nuclear response functions, as laid out in [Fitzpatrick et al, arXiv:1203.3542], on dark matter (DM) direct detection in the context of well-motivated UV completions, including electric and magnetic dipoles, anapole, spin-orbit, and pseudoscalar-mediated DM. Together, these encompass five of the six nuclear responses extracted from the non-relativistic effective theory of [Fitzpatrick et al, arXiv:1203.3542] (with the sixth difficult to UV complete), with two of the six combinations corresponding to standard spin-independent and -dependent responses. For constraints from existing direct detection experiments, we find that only the COUPP constraint, due to its heavy iodine target with large angular momentum and an unpaired spin, and its large energy range sensitivity, is substantially modified by the new responses compared to what would be inferred using the standard form factors to model the energy dependence of the response. For heavy targets such as xenon and germanium, the behavior of the new nuclear responses as recoil energy increases can be substantially different than that of the standard responses, but this has almost no impact on the constraints derived from experiments such as LUX, XENON100 and CDMS since the maximum nuclear recoil energy detected in these experiments is relatively low. We simulate mock data for 80 and 250 GeV DM candidates utilizing the new nuclear responses to highlight how they might affect a putative signal, and find the new responses are most important for momentum-suppressed interactions such as the magnetic dipole or pseudoscalar-mediated interaction when the target is relatively heavy (such as xenon and iodine). |
1304.5362 | P\'eter Kov\'acs Dr. | Peter Kovacs, Gyorgy Wolf | Meson vacuum phenomenology in a three-flavor linear sigma model with
(axial-)vector mesons: investigation of the U(1)_A anomaly term | Presented at Excited QCD 2013, 3-9 February 2013, Bjelasnica
Mountain, Sarajevo | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Zero temperature properties of an (axial-) vector meson extended linear sigma
model are discussed, concerning on the possible different realizations of the
axial anomaly term. The different anomaly terms are compared with each other on
the basis of a chi^2 minimalization process. It is found that there is no
essential difference among the different realizations. This means that any of
them can be equally used from phenomenological point of view.
| [
{
"created": "Fri, 19 Apr 2013 10:03:48 GMT",
"version": "v1"
}
] | 2013-04-22 | [
[
"Kovacs",
"Peter",
""
],
[
"Wolf",
"Gyorgy",
""
]
] | Zero temperature properties of an (axial-) vector meson extended linear sigma model are discussed, concerning on the possible different realizations of the axial anomaly term. The different anomaly terms are compared with each other on the basis of a chi^2 minimalization process. It is found that there is no essential difference among the different realizations. This means that any of them can be equally used from phenomenological point of view. |
hep-ph/9212262 | John N. Bahcall | John Bahcall | Summary Talk: International Symposium on Neutrino Astrophysics,
Takayama/Kamioka (10/'92) | 11 pages (figures not included). For a hard copy with the figures,
write: BEST@IASSNS.BITNET. Institute for | null | null | Advanced Study number AST 92/59. | hep-ph astro-ph | null | Contents:
1. The Conference
2. Solar Neutrinos
-A. Operating Experiments
-B. New Funded Experiments
-C. Are Solar Neutrino Fluxes Time Dependent?
-D. Have $pp$ Neutrinos Been Detected?
-E. Is Directionality Required for Astronomical Observations?
-F. Is There a Solar Neutrino Problem?
-G. What Have We Learned?
3. Supernova Neutrinos
4. Atmospheric Neutrinos
5. High-Energy Neutrinos
6. Our Field Is Flourishing
| [
{
"created": "Mon, 14 Dec 1992 18:52:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bahcall",
"John",
""
]
] | Contents: 1. The Conference 2. Solar Neutrinos -A. Operating Experiments -B. New Funded Experiments -C. Are Solar Neutrino Fluxes Time Dependent? -D. Have $pp$ Neutrinos Been Detected? -E. Is Directionality Required for Astronomical Observations? -F. Is There a Solar Neutrino Problem? -G. What Have We Learned? 3. Supernova Neutrinos 4. Atmospheric Neutrinos 5. High-Energy Neutrinos 6. Our Field Is Flourishing |
1905.11778 | Syuhei Iguro | Syuhei Iguro and Yuji Omura | The direct CP violation in a general two Higgs doublet model | 20 pages, 5 figures, typo corrected | null | 10.1007/JHEP08(2019)098 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we study the CP violating processes in a general
two-Higgs-doublet model (2HDM) with tree-level flavor changing neutral
currents. In this model, sizable Yukawa couplings involving top and charm
quarks are still allowed by the collider and flavor experiments, while the
other couplings are strongly constrained experimentally. The sizable couplings,
in general, have imaginary parts and could largely contribute to the CP
violating observables concerned with the $B$ and $K$ mesons. In particular, the
contribution may be so large that it affects the direct CP violating $K$ meson
decay, where the discrepancy between the experimental result and the Standard
Model prediction is reported. We discuss how well the anomaly is resolved in
the 2HDM, based on study of the other flavor observables. We also propose the
way to test our 2HDM at the LHC.
| [
{
"created": "Tue, 28 May 2019 12:46:55 GMT",
"version": "v1"
},
{
"created": "Sun, 8 Sep 2019 23:03:14 GMT",
"version": "v2"
},
{
"created": "Mon, 21 Nov 2022 09:48:26 GMT",
"version": "v3"
}
] | 2022-11-22 | [
[
"Iguro",
"Syuhei",
""
],
[
"Omura",
"Yuji",
""
]
] | In this paper, we study the CP violating processes in a general two-Higgs-doublet model (2HDM) with tree-level flavor changing neutral currents. In this model, sizable Yukawa couplings involving top and charm quarks are still allowed by the collider and flavor experiments, while the other couplings are strongly constrained experimentally. The sizable couplings, in general, have imaginary parts and could largely contribute to the CP violating observables concerned with the $B$ and $K$ mesons. In particular, the contribution may be so large that it affects the direct CP violating $K$ meson decay, where the discrepancy between the experimental result and the Standard Model prediction is reported. We discuss how well the anomaly is resolved in the 2HDM, based on study of the other flavor observables. We also propose the way to test our 2HDM at the LHC. |
1510.03112 | Matthias Burkardt | Matthias Burkardt (New Mexico State University) | Transverse Force on Quarks in DIS | 6 pages, invited talk at DIS2015 | Phys. Rev. D 94, 094016 (2016) | 10.1103/PhysRevD.94.094016 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Generalized Parton Distributions (GPDs) provide information on the
distribution of quarks in impact paarmeter space. For transversely polarized
nucleons, these impact parameter distributions are transversely distorted and
this deviation from axial symmetry leads on average to a net transverse force
from the spectators on the active quark in a DIS experiment. %The strength of
that force can be related to twist-3 PDFs. This force when acting along the
whole trajectory of the active quark leads to a transverse single-spin
asymmetries. For a longitudinally polarized nucleon target, the transverse
force implies a torque acting on the quark Orbital Angular Momentum (OAM). The
resulting change in OAM as the quark leaves the target equals the difference
between the Jaffe-Manohar and Ji OAMs.
| [
{
"created": "Sun, 11 Oct 2015 23:38:41 GMT",
"version": "v1"
}
] | 2016-11-23 | [
[
"Burkardt",
"Matthias",
"",
"New Mexico State University"
]
] | Generalized Parton Distributions (GPDs) provide information on the distribution of quarks in impact paarmeter space. For transversely polarized nucleons, these impact parameter distributions are transversely distorted and this deviation from axial symmetry leads on average to a net transverse force from the spectators on the active quark in a DIS experiment. %The strength of that force can be related to twist-3 PDFs. This force when acting along the whole trajectory of the active quark leads to a transverse single-spin asymmetries. For a longitudinally polarized nucleon target, the transverse force implies a torque acting on the quark Orbital Angular Momentum (OAM). The resulting change in OAM as the quark leaves the target equals the difference between the Jaffe-Manohar and Ji OAMs. |
hep-ph/9911263 | Sechul Oh | B. Dutta and Sechul Oh | Charmless hadronic B decays and the recent CLEO data | 24 pages, 11 figures, LaTex; Version to appear in Phys. Rev. D | Phys.Rev. D63 (2001) 054016 | 10.1103/PhysRevD.63.054016 | CTP-TAMU-43-99, COLO-HEP-439 | hep-ph | null | In the light of recent experimental data from the CLEO Collaboration we
study, the decays of B mesons to a pair of pseudoscalar (P) mesons, and a
vector (V) meson and a pseudoscalar meson, in the framework of factorization.
In order to obtain the best fit for the recent CLEO data, we critically examine
the values of several input parameters to which the predictions are sensitive.
These input parameters are the form factors, the strange quark mass, $\xi
\equiv 1/ N_c$ (N_c is the effective number of color), the CKM matrix elements
and in particular, the weak phase $\gamma$. It is possible to give a
satisfactory account of the recent experimental results in $B \to PP$ and VP
decays, with constrained values of a \emph{single} $\xi$. We identify the decay
modes in which CP asymmetries are expected to be large.
| [
{
"created": "Fri, 5 Nov 1999 23:46:22 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Jan 2001 07:55:01 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Dutta",
"B.",
""
],
[
"Oh",
"Sechul",
""
]
] | In the light of recent experimental data from the CLEO Collaboration we study, the decays of B mesons to a pair of pseudoscalar (P) mesons, and a vector (V) meson and a pseudoscalar meson, in the framework of factorization. In order to obtain the best fit for the recent CLEO data, we critically examine the values of several input parameters to which the predictions are sensitive. These input parameters are the form factors, the strange quark mass, $\xi \equiv 1/ N_c$ (N_c is the effective number of color), the CKM matrix elements and in particular, the weak phase $\gamma$. It is possible to give a satisfactory account of the recent experimental results in $B \to PP$ and VP decays, with constrained values of a \emph{single} $\xi$. We identify the decay modes in which CP asymmetries are expected to be large. |
hep-ph/0112170 | Ephraim Fischbach | E. Fischbach, A.W. Overhauser, and B. Woodahl | Corrections to Fermi's Golden Rule in $\phi \to K\bar{K}$ Decays | null | Phys.Lett.B526:355-359,2002 | 10.1016/S0370-2693(01)01520-9 | null | hep-ph | null | We analyze the decays $\phi \to K\bar{K}$ utilizing a formulation of
transition rates which explicitly exhibits corrections to Fermi's Golden Rule.
These corrections arise in systems in which the phase space and/or matrix
element varies rapidly with energy, as happens in $\phi \to K\bar{K}$, which is
just above threshold. We show that the theoretical corrections resolve a
puzzling $5\sigma$ discrepancy between theory and experiment for the branching
ratio $R = \Gamma (\phi \to K^+K^-)/\Gamma(\phi \to K^0\bar{K}^0)$.
| [
{
"created": "Wed, 12 Dec 2001 20:24:47 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Fischbach",
"E.",
""
],
[
"Overhauser",
"A. W.",
""
],
[
"Woodahl",
"B.",
""
]
] | We analyze the decays $\phi \to K\bar{K}$ utilizing a formulation of transition rates which explicitly exhibits corrections to Fermi's Golden Rule. These corrections arise in systems in which the phase space and/or matrix element varies rapidly with energy, as happens in $\phi \to K\bar{K}$, which is just above threshold. We show that the theoretical corrections resolve a puzzling $5\sigma$ discrepancy between theory and experiment for the branching ratio $R = \Gamma (\phi \to K^+K^-)/\Gamma(\phi \to K^0\bar{K}^0)$. |
2309.01060 | Arslan Sikandar | Arslan Sikandar, M. Jamil Aslam, Ishtiaq Ahmed, Saba Shafaq | Radiative $B$ to axial-vector meson decays at NLO in Soft-Collinear
Effective Theory | null | J.Phys.G 48 (2021) 4, 045005 | 10.1088/1361-6471/abdadd | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The rare decay $B\rightarrow A\gamma$, with $A$ representing axial-vector
mesons such as $K_1 (1270),\; K_1 (1400),\; b_1(1300),\; a_1(1260)$, is studied
at next-to-leading order (NLO) in soft collinear effective theory (SCET). The
large outgoing meson energy encourages the study of the decay with an
appropriate factorization scheme that separates the factorizable and
non-factorizable parts systematically. We have analyzed the leading-power and
$\mathcal{O}(\alpha_s)$ diagrams that contribute to matching to SCET$_I$. The
new intermediate theory is matched onto SCET$_{II}$ and the running of SCET$_I$
operators is performed to sum large perturbative logarithms. The values of
soft-overlap function $\zeta_{\perp}$ for $K_1 (1270,\;1400), a_{1}$ and
$b_{1}$ mesons are estimated from the light cone-sum-rules (LCSR), and later
using it the corresponding branching fractions for $B \to \left(K_{1}(1270,\;
1400),\; a_{1},\; b_{1}\right)\gamma$ decays are calculated. We find that in
case of $B \to K_{1}(1270,\; 1400)\gamma$ decays the results are in good
agreement with their experimental measurements. Also the estimated values of
the branching ratios of the $B \to (b_{1},\; a_1)\gamma$ decays are potentially
large to be measured at the LHCb and future B-factories.
| [
{
"created": "Sun, 3 Sep 2023 03:03:01 GMT",
"version": "v1"
}
] | 2023-09-06 | [
[
"Sikandar",
"Arslan",
""
],
[
"Aslam",
"M. Jamil",
""
],
[
"Ahmed",
"Ishtiaq",
""
],
[
"Shafaq",
"Saba",
""
]
] | The rare decay $B\rightarrow A\gamma$, with $A$ representing axial-vector mesons such as $K_1 (1270),\; K_1 (1400),\; b_1(1300),\; a_1(1260)$, is studied at next-to-leading order (NLO) in soft collinear effective theory (SCET). The large outgoing meson energy encourages the study of the decay with an appropriate factorization scheme that separates the factorizable and non-factorizable parts systematically. We have analyzed the leading-power and $\mathcal{O}(\alpha_s)$ diagrams that contribute to matching to SCET$_I$. The new intermediate theory is matched onto SCET$_{II}$ and the running of SCET$_I$ operators is performed to sum large perturbative logarithms. The values of soft-overlap function $\zeta_{\perp}$ for $K_1 (1270,\;1400), a_{1}$ and $b_{1}$ mesons are estimated from the light cone-sum-rules (LCSR), and later using it the corresponding branching fractions for $B \to \left(K_{1}(1270,\; 1400),\; a_{1},\; b_{1}\right)\gamma$ decays are calculated. We find that in case of $B \to K_{1}(1270,\; 1400)\gamma$ decays the results are in good agreement with their experimental measurements. Also the estimated values of the branching ratios of the $B \to (b_{1},\; a_1)\gamma$ decays are potentially large to be measured at the LHCb and future B-factories. |
hep-ph/9403208 | Jean-Marc Richard | E.Bagan, H.G.Dosch, P.Gosdzinsky, S.Narison and J.M.Richard | Hadrons with Charm and Beauty | 32 pages, LaTeX, no changes in the 1994 paper, latex errors corrected
in 2014 | Z.Phys.C64:57-72,1994 | 10.1007/BF01557235 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By combining potential models and QCD spectral sum rules (QSSR), we discuss
the spectroscopy of the $(b\bar c)$ mesons and of the $(bcq)$, $(ccq)$ and
$(bbq)$ baryons (${q}\equiv {d}$ or $s$), the decay constant and the
(semi)leptonic decay modes of the $B_c$ meson. For the masses, the best
predictions come from potential models and read: $M_{B_c} = (6255 \pm 20)$~MeV,
$M_{B^*_c} = (6330 \pm 20)$~MeV, $M_{\Lambda(bcu)} = (6.93\pm 0.05)$~GeV,
$M_{\Omega(bcs)} = (7.00\pm 0.05)$~GeV, $M_{\Xi^*(ccu)} =(3.63\pm 0.05)$~GeV
and $M_{\Xi^*(bbu)} = (10.21\pm 0.05)$~GeV. The decay constant $f_{B_c} = (2.94
\pm 0.21) f_\pi $ is well determined from QSSR and leads to: $\Gamma(B_c
\rightarrow \nu_\tau \tau) = (3.0 \pm 0.4)( V_{cb}/0.037 )^2$ $\times 10^{10}$
s$^{-1}$.The uses of the vertex sum rules for the semileptonic decays of the
$B_c$ show that the $t$-dependence of the form factors is much stronger than
predicted by vector meson dominance. It also predicts the almost equal strength
of about 0.30 $\times 10^{10}$ sec$^{-1}$ for the semileptonic rates $B_c$ into
$B_s, B^*_s,\eta_c$ and J/$\psi$. Besides these phenomenological results, we
also show explicitly how the Wilson coefficients of the $\langle\alpha_s
G^2\rangle$ and $\langle G^3\rangle$ gluon condensates already contain the full
heavy quark- ($\langle\bar QQ\rangle$) and mixed- ($\langle\bar QGQ\rangle$)
condensate contributions in the OPE.}
| [
{
"created": "Wed, 2 Mar 1994 11:00:27 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Sep 2014 15:06:23 GMT",
"version": "v2"
}
] | 2014-09-17 | [
[
"Bagan",
"E.",
""
],
[
"Dosch",
"H. G.",
""
],
[
"Gosdzinsky",
"P.",
""
],
[
"Narison",
"S.",
""
],
[
"Richard",
"J. M.",
""
]
] | By combining potential models and QCD spectral sum rules (QSSR), we discuss the spectroscopy of the $(b\bar c)$ mesons and of the $(bcq)$, $(ccq)$ and $(bbq)$ baryons (${q}\equiv {d}$ or $s$), the decay constant and the (semi)leptonic decay modes of the $B_c$ meson. For the masses, the best predictions come from potential models and read: $M_{B_c} = (6255 \pm 20)$~MeV, $M_{B^*_c} = (6330 \pm 20)$~MeV, $M_{\Lambda(bcu)} = (6.93\pm 0.05)$~GeV, $M_{\Omega(bcs)} = (7.00\pm 0.05)$~GeV, $M_{\Xi^*(ccu)} =(3.63\pm 0.05)$~GeV and $M_{\Xi^*(bbu)} = (10.21\pm 0.05)$~GeV. The decay constant $f_{B_c} = (2.94 \pm 0.21) f_\pi $ is well determined from QSSR and leads to: $\Gamma(B_c \rightarrow \nu_\tau \tau) = (3.0 \pm 0.4)( V_{cb}/0.037 )^2$ $\times 10^{10}$ s$^{-1}$.The uses of the vertex sum rules for the semileptonic decays of the $B_c$ show that the $t$-dependence of the form factors is much stronger than predicted by vector meson dominance. It also predicts the almost equal strength of about 0.30 $\times 10^{10}$ sec$^{-1}$ for the semileptonic rates $B_c$ into $B_s, B^*_s,\eta_c$ and J/$\psi$. Besides these phenomenological results, we also show explicitly how the Wilson coefficients of the $\langle\alpha_s G^2\rangle$ and $\langle G^3\rangle$ gluon condensates already contain the full heavy quark- ($\langle\bar QQ\rangle$) and mixed- ($\langle\bar QGQ\rangle$) condensate contributions in the OPE.} |
1610.05497 | Marco Bonetti | Marco Bonetti, Kirill Melnikov, Lorenzo Tancredi | Two-loop electroweak corrections to Higgs-gluon couplings to higher
orders in the dimensional regularization parameter | 18 pages, 2 figures, 1 table, Mathematica readable file with results | null | 10.1016/j.nuclphysb.2017.01.020 | TTP16-045 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the two-loop electroweak correction to the production of the Higgs
boson in gluon fusion to higher orders in the dimensional-regularization
parameter $\epsilon = (d-4)/2$. We employ the method of differential equations
to compute the relevant integrals and express them in terms of Goncharov
polylogarithms. Our result provides one of the necessary inputs for the
computation of mixed three-loop QCD-electroweak corrections to $gg \to H$.
| [
{
"created": "Tue, 18 Oct 2016 09:22:57 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Feb 2017 09:50:48 GMT",
"version": "v2"
}
] | 2017-03-08 | [
[
"Bonetti",
"Marco",
""
],
[
"Melnikov",
"Kirill",
""
],
[
"Tancredi",
"Lorenzo",
""
]
] | We compute the two-loop electroweak correction to the production of the Higgs boson in gluon fusion to higher orders in the dimensional-regularization parameter $\epsilon = (d-4)/2$. We employ the method of differential equations to compute the relevant integrals and express them in terms of Goncharov polylogarithms. Our result provides one of the necessary inputs for the computation of mixed three-loop QCD-electroweak corrections to $gg \to H$. |
1308.4379 | Christian Hambrock | Christian Hambrock, Gudrun Hiller, Stefan Schacht, Roman Zwicky | B -> K^* Form Factors from Flavor Data to QCD and Back | 25 pages. References and clarifications added. Conclusions unchanged | Phys. Rev. D 89, 074014 2014 | 10.1103/PhysRevD.89.074014 | DO-TH 13/13, QFET-2013-04, Edinburgh /13/17, CP^3-Origins-2013-025,
DIAS-2013-25 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Sufficient control of transition form factors is a vital ingredient for the
precision flavor programs including the nearer term searches at the Large
Hadron Collider (LHC) and the forthcoming Belle II experiment. We improve on
existing methods to extract B -> K^* form factor ratios at low hadronic recoil
from B -> K^* l^+ l^- data on the angular observables F_L, A_T^(2) and P'_4 by
adding heavy quark symmetry-based constraints and by investigating the cross
talk between low and large recoil. The data-extracted form factor ratios i)
provide benchmarks for the lattice and light cone sum rule predictions, the
latter of which have been updated including improved uncertainty estimations
and ii) allow to improve the predictions for benchmark observables. We find
that present data on the forward-backward asymmetry A_FB and the angular
observable P'_5 at low recoil are in good agreement with the Standard Model.
| [
{
"created": "Tue, 20 Aug 2013 19:01:56 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Mar 2014 15:55:40 GMT",
"version": "v2"
}
] | 2014-06-03 | [
[
"Hambrock",
"Christian",
""
],
[
"Hiller",
"Gudrun",
""
],
[
"Schacht",
"Stefan",
""
],
[
"Zwicky",
"Roman",
""
]
] | Sufficient control of transition form factors is a vital ingredient for the precision flavor programs including the nearer term searches at the Large Hadron Collider (LHC) and the forthcoming Belle II experiment. We improve on existing methods to extract B -> K^* form factor ratios at low hadronic recoil from B -> K^* l^+ l^- data on the angular observables F_L, A_T^(2) and P'_4 by adding heavy quark symmetry-based constraints and by investigating the cross talk between low and large recoil. The data-extracted form factor ratios i) provide benchmarks for the lattice and light cone sum rule predictions, the latter of which have been updated including improved uncertainty estimations and ii) allow to improve the predictions for benchmark observables. We find that present data on the forward-backward asymmetry A_FB and the angular observable P'_5 at low recoil are in good agreement with the Standard Model. |
0812.1854 | Hye-Sung Lee | Hye-Sung Lee | Dileptons and four leptons at Z' resonance in the early stage of the LHC | Version to appear in PLB | Phys.Lett.B674:87-91,2009 | 10.1016/j.physletb.2009.02.058 | UCRHEP-T460 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The LHC era just began. The first discovery at the LHC experiment would be
arguably a new resonance pole at TeV scale, if it exists. While the discovery
of the Z' would be exciting by itself, it may also suggest what other new
physics signals should be looked for while the LHC experiment is still at its
early stage. We argue that the four lepton resonance at the Z' pole is a
well-motivated and promising signal especially in supersymmetry framework,
which can serve as a supersymmetry search scheme even in the early stage of the
LHC experiment.
| [
{
"created": "Wed, 10 Dec 2008 20:36:17 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Mar 2009 22:26:29 GMT",
"version": "v2"
}
] | 2009-04-02 | [
[
"Lee",
"Hye-Sung",
""
]
] | The LHC era just began. The first discovery at the LHC experiment would be arguably a new resonance pole at TeV scale, if it exists. While the discovery of the Z' would be exciting by itself, it may also suggest what other new physics signals should be looked for while the LHC experiment is still at its early stage. We argue that the four lepton resonance at the Z' pole is a well-motivated and promising signal especially in supersymmetry framework, which can serve as a supersymmetry search scheme even in the early stage of the LHC experiment. |
1209.1675 | John Collins | Emil Avsar and John C. Collins | Inability to find justification of a $k_T$-factorization formula by
following chains of citations | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Fundamental to much work in small-x QCD is a k_T-factorization formula.
Normal expectations in theoretical physics are that when such a result is used,
citations should be given to where the formula is justified. We demonstrate by
examining the chains of citations back from current work that violations of
this expectation are widespread, to the extent that following the citation
chains, we do not find a proof or other justification of the formula. This
shows a substantial deficit in the reproducibility of a phenomenologically
important area of research. Since the published formulae differ in
normalization, we test them by making a derivation in a simple model that obeys
the assumptions that are stated in the literature to be the basis of
k_T-factorization in the small-$x$ regime. We find that we disagree with two of
the standard normalizations.
| [
{
"created": "Sat, 8 Sep 2012 00:51:24 GMT",
"version": "v1"
}
] | 2012-09-11 | [
[
"Avsar",
"Emil",
""
],
[
"Collins",
"John C.",
""
]
] | Fundamental to much work in small-x QCD is a k_T-factorization formula. Normal expectations in theoretical physics are that when such a result is used, citations should be given to where the formula is justified. We demonstrate by examining the chains of citations back from current work that violations of this expectation are widespread, to the extent that following the citation chains, we do not find a proof or other justification of the formula. This shows a substantial deficit in the reproducibility of a phenomenologically important area of research. Since the published formulae differ in normalization, we test them by making a derivation in a simple model that obeys the assumptions that are stated in the literature to be the basis of k_T-factorization in the small-$x$ regime. We find that we disagree with two of the standard normalizations. |
hep-ph/0605017 | Wei-Qin Zhao | T. D. Lee | New Insights to Old Problems | 16 pages, 3 figures | null | null | null | hep-ph | null | From the history of the $\theta$-$\tau$ puzzle and the discovery of parity
non-conservation in 1956, we review the current status of discrete symmetry
violations in the weak interaction. Possible origin of these symmetry
violations are discussed.
| [
{
"created": "Mon, 1 May 2006 02:49:46 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lee",
"T. D.",
""
]
] | From the history of the $\theta$-$\tau$ puzzle and the discovery of parity non-conservation in 1956, we review the current status of discrete symmetry violations in the weak interaction. Possible origin of these symmetry violations are discussed. |
hep-ph/0507292 | Christopher D. Carone | Christopher D. Carone and Justin M. Conroy (William and Mary) | Five-dimensional Trinification Improved | 13 pages LaTeX. v2: reference added | Phys.Lett. B626 (2005) 195-201 | 10.1016/j.physletb.2005.08.111 | WM-05-114 | hep-ph | null | We present improved models of trinification in five dimensions. Unified
symmetry is broken by a combination of orbifold projections and a boundary
Higgs sector. The latter can be decoupled from the theory, realizing a
Higgsless limit in which the scale of exotic massive gauge fields is set by the
compactification radius. Electroweak Higgs doublets are identified with the
fifth components of gauge fields and Yukawa interactions arise via Wilson
loops. The result is a simple low-energy effective theory that is consistent
with the constraints from proton decay and gauge unification.
| [
{
"created": "Mon, 25 Jul 2005 20:45:48 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jul 2005 19:03:20 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Carone",
"Christopher D.",
"",
"William and Mary"
],
[
"Conroy",
"Justin M.",
"",
"William and Mary"
]
] | We present improved models of trinification in five dimensions. Unified symmetry is broken by a combination of orbifold projections and a boundary Higgs sector. The latter can be decoupled from the theory, realizing a Higgsless limit in which the scale of exotic massive gauge fields is set by the compactification radius. Electroweak Higgs doublets are identified with the fifth components of gauge fields and Yukawa interactions arise via Wilson loops. The result is a simple low-energy effective theory that is consistent with the constraints from proton decay and gauge unification. |
1103.2042 | Andrey Radzhabov E | A.E. Dorokhov, A.E. Radzhabov and A.S. Zhevlakov | The pseudoscalar hadronic channel contribution of the light-by-light
process to the muon (g-2) within the nonlocal chiral quark model | 11 pages, 7 figures; version for journal, minor corrections are made | Eur.Phys.J.C71:1702,2011 | 10.1140/epjc/s10052-011-1702-6 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The light-by-light contribution to the anomalous magnetic moment of muon
(g-2)_{\mu} from the hadronic exchanges in the neutral pseudoscalar meson
channel is calculated in the nonlocal chiral quark model. The full kinematic
dependence of the meson-two-photon vertices on the virtualities of the mesons
and photons is taken into account. The status of various phenomenological and
QCD short-distance constraints is discussed and the comparison with the
predictions of other models is performed. It is demonstrated that the effect of
the full kinematic dependence in the meson-photon vertices is to reduce the
contribution of pseudoscalar exchages to a_\mu ^{PS,LbL} by approximately
factor 1.5 in comparison with the most of previous estimates.
| [
{
"created": "Thu, 10 Mar 2011 14:17:05 GMT",
"version": "v1"
},
{
"created": "Thu, 17 Mar 2011 12:33:44 GMT",
"version": "v2"
}
] | 2011-07-21 | [
[
"Dorokhov",
"A. E.",
""
],
[
"Radzhabov",
"A. E.",
""
],
[
"Zhevlakov",
"A. S.",
""
]
] | The light-by-light contribution to the anomalous magnetic moment of muon (g-2)_{\mu} from the hadronic exchanges in the neutral pseudoscalar meson channel is calculated in the nonlocal chiral quark model. The full kinematic dependence of the meson-two-photon vertices on the virtualities of the mesons and photons is taken into account. The status of various phenomenological and QCD short-distance constraints is discussed and the comparison with the predictions of other models is performed. It is demonstrated that the effect of the full kinematic dependence in the meson-photon vertices is to reduce the contribution of pseudoscalar exchages to a_\mu ^{PS,LbL} by approximately factor 1.5 in comparison with the most of previous estimates. |
hep-ph/9907394 | Jonathan Butterworth | J.M.Butterworth and R.J.Taylor | A Global Study of Photon-Induced Jet Production | 6 Pages, 5 figures, To appear in proceedings of Photon99, Freiburg.
Further results are available at http://www.hep.ucl.ac.uk/~jmb/HZTOOL/ | Nucl.Phys.Proc.Suppl. 82 (2000) 112-117 | 10.1016/S0920-5632(00)00140-7 | UCL/HEP 99-05 | hep-ph | null | We present results of a global tuning of general purpose Monte Carlo models
to published measurements of photon-proton -> jets at HERA and photon-photon ->
jets at LEP and TRISTAN. The principle free parameters in the tuning are the
simulation of the underlying event and the choice of photon structure. Several
combinations of models are ruled out by the data. Some consequences of the
tuned models at a future linear collider are discussed.
| [
{
"created": "Fri, 16 Jul 1999 17:08:48 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Butterworth",
"J. M.",
""
],
[
"Taylor",
"R. J.",
""
]
] | We present results of a global tuning of general purpose Monte Carlo models to published measurements of photon-proton -> jets at HERA and photon-photon -> jets at LEP and TRISTAN. The principle free parameters in the tuning are the simulation of the underlying event and the choice of photon structure. Several combinations of models are ruled out by the data. Some consequences of the tuned models at a future linear collider are discussed. |
hep-ph/9606472 | Per Ernstroem | Per Ernstrom, Leif Lonnblad (NORDITA) | Generating heavy quarkonia in a perturbative QCD cascade | 20 pages, LaTeX, uses the cite and graphics packages. Version 2,
accepted for publication in Z. Phys. C, contains a new paragraph in the
beginning of section 2 as well as in the conclusions. The references have
been modified slightly | Z.Phys. C75 (1997) 51-56 | null | NORDITA-96/40 P | hep-ph | null | We present an implementation of heavy quarkonium production within a
perturbative QCD cascade based on the Colour Dipole Cascade model. We consider
the processes most relevant in the context of the psi' surplus at the Tevatron;
g -> psi' and c -> psi' in the colour-singlet model and g -> psi' through the
colour-octet mechanism. Our implementation is, however, easily extendible to
other quarkonia and other production mechanisms. Where comparison is possible
we find good agreement with analytical calculations. We present some
suggestions for measurements at the Tevatron that would be sensitive to the
shape of the fragmentation functions. Our calculations indicate that such
measurements could be used to test the colour-octet mechanism solution to the
psi' surplus at the Tevatron.
| [
{
"created": "Fri, 28 Jun 1996 13:29:50 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Aug 1996 14:23:41 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Ernstrom",
"Per",
"",
"NORDITA"
],
[
"Lonnblad",
"Leif",
"",
"NORDITA"
]
] | We present an implementation of heavy quarkonium production within a perturbative QCD cascade based on the Colour Dipole Cascade model. We consider the processes most relevant in the context of the psi' surplus at the Tevatron; g -> psi' and c -> psi' in the colour-singlet model and g -> psi' through the colour-octet mechanism. Our implementation is, however, easily extendible to other quarkonia and other production mechanisms. Where comparison is possible we find good agreement with analytical calculations. We present some suggestions for measurements at the Tevatron that would be sensitive to the shape of the fragmentation functions. Our calculations indicate that such measurements could be used to test the colour-octet mechanism solution to the psi' surplus at the Tevatron. |
2407.14585 | Claudio Andrea Manzari | Lawrence Hall, Claudio Andrea Manzari, Bea Noether | Strong CP and Flavor in Multi-Higgs Theories | 29 pages, 3 figures, 5 tables | null | null | null | hep-ph hep-ex hep-th | http://creativecommons.org/licenses/by/4.0/ | We introduce a class of multi-Higgs doublet extensions of the Standard Model
that solves the strong CP problem with profound consequences for the flavor
sector. The Yukawa matrices are constrained to have many zero entries by a
"Higgs-Flavor" symmetry, $G_{\rm HF}$, that acts on Higgs and quark fields. The
violation of both CP and $G_{\rm HF}$ occurs in the Higgs mass matrix so that,
for certain choices of $G_{\rm HF}$ charges, the strong CP parameter
$\bar{\theta}$ is zero at tree-level. Radiative corrections to $\bar{\theta}$
are computed in this class of theories. They vanish in realistic two-Higgs
doublet models with $G_{\rm HF} = \mathbb{Z}_3$. We also construct realistic
three-Higgs models with $G_{\rm HF} = \rm U(1)$, where the one-loop results for
$\bar{\theta}$ are model-dependent. Requiring $\bar{\theta}< 10^{-10}$ has
important implications for the flavor problem by constraining the Yukawa
coupling and Higgs mass matrices. Contributions to $\bar{\theta}$ from
higher-dimension operators are computed at 1-loop and can also be sufficiently
small, although the hierarchy problem of this class of theories is worse than
in the Standard Model.
| [
{
"created": "Fri, 19 Jul 2024 18:00:00 GMT",
"version": "v1"
}
] | 2024-07-23 | [
[
"Hall",
"Lawrence",
""
],
[
"Manzari",
"Claudio Andrea",
""
],
[
"Noether",
"Bea",
""
]
] | We introduce a class of multi-Higgs doublet extensions of the Standard Model that solves the strong CP problem with profound consequences for the flavor sector. The Yukawa matrices are constrained to have many zero entries by a "Higgs-Flavor" symmetry, $G_{\rm HF}$, that acts on Higgs and quark fields. The violation of both CP and $G_{\rm HF}$ occurs in the Higgs mass matrix so that, for certain choices of $G_{\rm HF}$ charges, the strong CP parameter $\bar{\theta}$ is zero at tree-level. Radiative corrections to $\bar{\theta}$ are computed in this class of theories. They vanish in realistic two-Higgs doublet models with $G_{\rm HF} = \mathbb{Z}_3$. We also construct realistic three-Higgs models with $G_{\rm HF} = \rm U(1)$, where the one-loop results for $\bar{\theta}$ are model-dependent. Requiring $\bar{\theta}< 10^{-10}$ has important implications for the flavor problem by constraining the Yukawa coupling and Higgs mass matrices. Contributions to $\bar{\theta}$ from higher-dimension operators are computed at 1-loop and can also be sufficiently small, although the hierarchy problem of this class of theories is worse than in the Standard Model. |
1007.1614 | Mads Toudal Frandsen | Mads T. Frandsen, Thomas Pickup and Michael Teper (Oxford U.) | Delineating the conformal window | 8 pages, 4 figures | Phys.Lett.B695:231-237,2011 | 10.1016/j.physletb.2010.10.064 | null | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We identify and characterise the conformal window in gauge theories relevant
for beyond the standard model building, e.g. Technicolour, using the criteria
of metric confinement and causal analytic couplings, which are known to be
consistent with the phase diagram of supersymmetric QCD from Seiberg duality.
Using these criteria we find perturbation theory to be consistent throughout
the predicted conformal window for several of these gauge theories and we
discuss recent lattice results in the light of our findings.
| [
{
"created": "Fri, 9 Jul 2010 15:43:22 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Jul 2010 13:40:47 GMT",
"version": "v2"
}
] | 2011-06-27 | [
[
"Frandsen",
"Mads T.",
"",
"Oxford U."
],
[
"Pickup",
"Thomas",
"",
"Oxford U."
],
[
"Teper",
"Michael",
"",
"Oxford U."
]
] | We identify and characterise the conformal window in gauge theories relevant for beyond the standard model building, e.g. Technicolour, using the criteria of metric confinement and causal analytic couplings, which are known to be consistent with the phase diagram of supersymmetric QCD from Seiberg duality. Using these criteria we find perturbation theory to be consistent throughout the predicted conformal window for several of these gauge theories and we discuss recent lattice results in the light of our findings. |
1309.5957 | Eric Kuflik | Csaba Csaki, Eric Kuflik, Tomer Volansky | Dynamical R-Parity Violation | 6 pages, 3 figures | Phys. Rev. Lett. 112, 131801 (2014) | 10.1103/PhysRevLett.112.131801 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a new paradigm for supersymmetric theories with R-parity violation
(RPV). At high scale, R-parity is conserved in the visible sector but
spontaneously broken in the SUSY-breaking sector. The breaking is then
dynamically mediated to the visible sector and is manifested via
non-renormalizable operators at low energy. Consequently, RPV operators
originate from the Kahler potential rather than the superpotential, and are
naturally suppressed by the SUSY-breaking scale, explaining their small
magnitudes. A new set of non-holomorphic RPV operators are identified and found
to often dominate over the standard RPV ones. We study the relevant low-energy
constraints arising from baryon-number violating processes, proton decay and
flavor changing neutral currents, which may all be satisfied if a solution to
the Standard Model flavor puzzle is incorporated. The chiral structure of the
RPV operators imply new and distinct collider signatures, indicating the need
to alter current techniques in searching for RPV at the LHC.
| [
{
"created": "Mon, 23 Sep 2013 20:00:02 GMT",
"version": "v1"
}
] | 2014-04-23 | [
[
"Csaki",
"Csaba",
""
],
[
"Kuflik",
"Eric",
""
],
[
"Volansky",
"Tomer",
""
]
] | We present a new paradigm for supersymmetric theories with R-parity violation (RPV). At high scale, R-parity is conserved in the visible sector but spontaneously broken in the SUSY-breaking sector. The breaking is then dynamically mediated to the visible sector and is manifested via non-renormalizable operators at low energy. Consequently, RPV operators originate from the Kahler potential rather than the superpotential, and are naturally suppressed by the SUSY-breaking scale, explaining their small magnitudes. A new set of non-holomorphic RPV operators are identified and found to often dominate over the standard RPV ones. We study the relevant low-energy constraints arising from baryon-number violating processes, proton decay and flavor changing neutral currents, which may all be satisfied if a solution to the Standard Model flavor puzzle is incorporated. The chiral structure of the RPV operators imply new and distinct collider signatures, indicating the need to alter current techniques in searching for RPV at the LHC. |
1904.04043 | Jusak Tandean | Xiao-Gang He, Jusak Tandean, German Valencia | Lepton-flavor-violating semileptonic $\tau$ decay and
$K\to\pi\nu\bar\nu$ | 16 pages, no figure, slightly expanded, references added, matches
journal version | Phys. Lett. B 797 (2019) 134842 | 10.1016/j.physletb.2019.134842 | NCTS-PH/1904 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider lepton-flavor violation in strangeness changing ($|\Delta S|=1$)
semileptonic $\tau$-lepton decays arising from new physics encoded in a
standard model effective Lagrangian. Its invariance under the standard model
gauge group entails the relevance of other processes which can serve as
complementary probes of the new physics operators. We show in particular that
for some of them the bounds implied by current data on the rare kaon decays
involving a neutrino pair, $K\to \pi\nu\bar\nu$, are stronger than the existing
limits from direct searches for lepton-flavor-violating semileptonic $\tau$
decays. We discuss additional processes affected by the same operators and find
that certain leptonic charged-meson decays also provide stricter constraints on
a few more of them. Upcoming results of ongoing experiments such as Belle II
and NA62 will further test the new physics parameter space.
| [
{
"created": "Mon, 8 Apr 2019 13:17:26 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Sep 2019 14:52:32 GMT",
"version": "v2"
}
] | 2019-09-11 | [
[
"He",
"Xiao-Gang",
""
],
[
"Tandean",
"Jusak",
""
],
[
"Valencia",
"German",
""
]
] | We consider lepton-flavor violation in strangeness changing ($|\Delta S|=1$) semileptonic $\tau$-lepton decays arising from new physics encoded in a standard model effective Lagrangian. Its invariance under the standard model gauge group entails the relevance of other processes which can serve as complementary probes of the new physics operators. We show in particular that for some of them the bounds implied by current data on the rare kaon decays involving a neutrino pair, $K\to \pi\nu\bar\nu$, are stronger than the existing limits from direct searches for lepton-flavor-violating semileptonic $\tau$ decays. We discuss additional processes affected by the same operators and find that certain leptonic charged-meson decays also provide stricter constraints on a few more of them. Upcoming results of ongoing experiments such as Belle II and NA62 will further test the new physics parameter space. |
2301.00329 | Waqas Ahmed | Waqas Ahmed, Athanasios Karozas, George K. Leontaris, Ilias Tavellaris | Hybrid Inflation, Reheating and Dark Radiation in a IIB perturbative
moduli stabilization scenario | Update version, Minor corrections and References added | Volume 2024, article number 282, (2024) | 10.1007/JHEP07(2024)282 | null | hep-ph hep-th | http://creativecommons.org/licenses/by-nc-sa/4.0/ | We study the cosmological implications of an effective field theory model
derived within a configuration of D7 brane stacks in the framework of type-IIB
string theory. We consider a suitable geometric setup where the K\"ahler moduli
fields are stabilized and the parametric space is constrained so that a de
Sitter vacuum is ensured. In addition to the moduli fields we also take into
account the usual Higgs and matter fields included in the effective field
theory. In this background, we implement the standard hybrid inflation scenario
with a singlet scalar field acting as the inflaton and the Higgs states serving
as waterfall fields. Radiative corrections and soft supersymmetry breaking
terms play an essential role in the realization of a successful inflationary
scenario consistent with the present cosmological data. Small tensor-to-scalar
ratio values are predicted, which can be probed in future planned experiments.
Further constraints on the model's parameters are derived from bounds on dark
radiation which is measured as a contribution to the effective number of
neutrino species $N_{\rm eff}$. In particular, we find an excess of $\Delta
N_{\rm eff}\leq{0.95}$ at $2\sigma$ confidence level with natural values of the
involved couplings.
| [
{
"created": "Sun, 1 Jan 2023 02:20:41 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Mar 2023 15:20:29 GMT",
"version": "v2"
},
{
"created": "Wed, 14 Feb 2024 04:03:16 GMT",
"version": "v3"
},
{
"created": "Fri, 2 Aug 2024 15:13:37 GMT",
"version": "v4"
}
] | 2024-08-05 | [
[
"Ahmed",
"Waqas",
""
],
[
"Karozas",
"Athanasios",
""
],
[
"Leontaris",
"George K.",
""
],
[
"Tavellaris",
"Ilias",
""
]
] | We study the cosmological implications of an effective field theory model derived within a configuration of D7 brane stacks in the framework of type-IIB string theory. We consider a suitable geometric setup where the K\"ahler moduli fields are stabilized and the parametric space is constrained so that a de Sitter vacuum is ensured. In addition to the moduli fields we also take into account the usual Higgs and matter fields included in the effective field theory. In this background, we implement the standard hybrid inflation scenario with a singlet scalar field acting as the inflaton and the Higgs states serving as waterfall fields. Radiative corrections and soft supersymmetry breaking terms play an essential role in the realization of a successful inflationary scenario consistent with the present cosmological data. Small tensor-to-scalar ratio values are predicted, which can be probed in future planned experiments. Further constraints on the model's parameters are derived from bounds on dark radiation which is measured as a contribution to the effective number of neutrino species $N_{\rm eff}$. In particular, we find an excess of $\Delta N_{\rm eff}\leq{0.95}$ at $2\sigma$ confidence level with natural values of the involved couplings. |
1308.2993 | Bowen Xiao | A. H. Mueller, Bo-Wen Xiao and Feng Yuan | Sudakov Double Logarithms Resummation in Hard Processes in Small-x
Saturation Formalism | 61 pages, 25 figures | Phys. Rev. D 88, 114010 (2013) | 10.1103/PhysRevD.88.114010 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this manuscript, we present a complete study of the Sudakov double
logarithms resummation for various hard processes in eA and pA collisions in
the small-x saturation formalism. We first employ a couple of slightly
different formalisms to perform the one-loop analysis of the Higgs boson
production process in pA collisions, and demonstrate that Sudakov-type
logarithms arise as the leading correction and that they can be systematically
resummed in addition to the usual small-x resummation. We further study the
Sudakov double logarithms for other processes such as heavy quark pair
production and back-to-back dijet production in eA and pA collisions through
detailed calculation of the corresponding one-loop diagrams. As the most
important contribution from the one-loop correction, the Sudakov factor should
play an important role in the phenomenological study of saturation physics in
the pA programs at RHIC and the LHC.
| [
{
"created": "Tue, 13 Aug 2013 23:12:44 GMT",
"version": "v1"
}
] | 2013-12-16 | [
[
"Mueller",
"A. H.",
""
],
[
"Xiao",
"Bo-Wen",
""
],
[
"Yuan",
"Feng",
""
]
] | In this manuscript, we present a complete study of the Sudakov double logarithms resummation for various hard processes in eA and pA collisions in the small-x saturation formalism. We first employ a couple of slightly different formalisms to perform the one-loop analysis of the Higgs boson production process in pA collisions, and demonstrate that Sudakov-type logarithms arise as the leading correction and that they can be systematically resummed in addition to the usual small-x resummation. We further study the Sudakov double logarithms for other processes such as heavy quark pair production and back-to-back dijet production in eA and pA collisions through detailed calculation of the corresponding one-loop diagrams. As the most important contribution from the one-loop correction, the Sudakov factor should play an important role in the phenomenological study of saturation physics in the pA programs at RHIC and the LHC. |
0809.1859 | C. Pallis | M.E. Gomez, S. Lola, C. Pallis and J. Rodriguez-Quintero | Quintessential Kination and Thermal Production of Gravitinos and Axinos | Published Version | JCAP 0901:027,2009 | 10.1088/1475-7516/2009/01/027 | null | hep-ph astro-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The impact of a kination-dominated phase generated by a quintessential
exponential model on the thermal abundance of gravitinos and axinos is
investigated. We find that their abundances become proportional to the
transition temperature from the kination to the radiation era; since this
temperature is significantly lower than the initial ("reheating") temperature,
the abundances decrease with respect to their values in the standard cosmology.
For values of the quintessential energy-density parameter close to its upper
bound, at the eve of nucleosynthesis, we find the following: (i) for unstable
gravitinos, the gravitino constraint is totally evaded; (ii) If the gravitino
is stable, its thermal abundance is not sufficient to account for the cold dark
matter of the universe; (iii) the thermal abundance of axinos can satisfy the
cold dark matter constraint for values of the initial temperature well above
those required in the standard cosmology. A novel calculation of the axino
production rate by scatterings at low temperature is also presented.
| [
{
"created": "Wed, 10 Sep 2008 19:35:26 GMT",
"version": "v1"
},
{
"created": "Sun, 7 Dec 2008 18:31:26 GMT",
"version": "v2"
},
{
"created": "Mon, 20 Jul 2009 18:48:22 GMT",
"version": "v3"
}
] | 2009-07-20 | [
[
"Gomez",
"M. E.",
""
],
[
"Lola",
"S.",
""
],
[
"Pallis",
"C.",
""
],
[
"Rodriguez-Quintero",
"J.",
""
]
] | The impact of a kination-dominated phase generated by a quintessential exponential model on the thermal abundance of gravitinos and axinos is investigated. We find that their abundances become proportional to the transition temperature from the kination to the radiation era; since this temperature is significantly lower than the initial ("reheating") temperature, the abundances decrease with respect to their values in the standard cosmology. For values of the quintessential energy-density parameter close to its upper bound, at the eve of nucleosynthesis, we find the following: (i) for unstable gravitinos, the gravitino constraint is totally evaded; (ii) If the gravitino is stable, its thermal abundance is not sufficient to account for the cold dark matter of the universe; (iii) the thermal abundance of axinos can satisfy the cold dark matter constraint for values of the initial temperature well above those required in the standard cosmology. A novel calculation of the axino production rate by scatterings at low temperature is also presented. |
hep-ph/0411069 | Wolfgang Lucha | Wolfgang Lucha, F. F. Schoberl | Spinless Salpeter Equation: Some (Semi-) Analytical Approaches | null | null | 10.1063/1.1921030 | null | hep-ph | null | Several techniques for deriving semianalytical bounds on the energy
eigenvalues of the spinless Salpeter equation and for estimating the quality of
the corresponding approximate eigenstates are reviewed.
| [
{
"created": "Thu, 4 Nov 2004 17:36:58 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Lucha",
"Wolfgang",
""
],
[
"Schoberl",
"F. F.",
""
]
] | Several techniques for deriving semianalytical bounds on the energy eigenvalues of the spinless Salpeter equation and for estimating the quality of the corresponding approximate eigenstates are reviewed. |
hep-ph/0205333 | Slava Yukalov | V.I. Yukalov and E.P. Yukalova | Do We Understand What Is Deconfinement? | Latex file, 18 pages | in Relativistic Nuclear Physics and Quantum Chromodynamics, edited
by A.M. Baldin, V.V. Burov, and A.I. Malakhov (Joint Inst. Nucl. Res., Dubna
2001), Vol. 1, p.109-126 | null | null | hep-ph cond-mat | null | An overview is given of different approaches to describing the process of
deconfinement in quantum chromodynamics. The analysis of the known approaches
demonstrates that the detailed picture of how deconfinement really occurs has
not yet been understood. Therefore, one has to be rather cautious when
interpreting experimental signals as attributed to deconfinement.
| [
{
"created": "Thu, 30 May 2002 08:23:39 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Yukalov",
"V. I.",
""
],
[
"Yukalova",
"E. P.",
""
]
] | An overview is given of different approaches to describing the process of deconfinement in quantum chromodynamics. The analysis of the known approaches demonstrates that the detailed picture of how deconfinement really occurs has not yet been understood. Therefore, one has to be rather cautious when interpreting experimental signals as attributed to deconfinement. |
hep-ph/9812241 | Yurii Surovtsev | T.D. Blokhintseva, M. Nagy and Yu.S.Surovtsev | Nucleon structure from the quasithreshold inverse pion electroproduction | 15 pages, LaTex; An extended version of the talk given at the
International Conference HADRON STRUCTURE'98 (Stara Lesna, High Tatra
Mountains, Slovak Republic; September 7-13, 1998) | null | null | null | hep-ph | null | The process $\pi N\to e^+e^- N$ (IPE), being a natural and unique laboratory
for studying the hadron electromagnetic structure in the
sub-$N\bar{N}$-threshold time-like region of the virtual-photon ``mass''
$\lambda^2$, turns out to be also very useful for investigating the nucleon
weak structure. A theoretical basis of the methods for extracting practically
model-independent values of the electromagnetic hadron form factors in the
time-like region and for determining the weak structure of the nucleon in the
space-like region from experimental data on IPE at low energies is outlined.
The results of extracting, by those methods, the electromagnetic
$F_1^v(\lambda^2)$ and pseudoscalar $G_P(t)$ form-factors of a nucleon are
presented, where an indication of the existence of the state $\pi^\p$ in the
range 500-800 MeV (possibly the first radial excitation of pion) is obtained,
and the coupling constant of this new state with the nucleon is estimated.
| [
{
"created": "Thu, 3 Dec 1998 16:22:44 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Blokhintseva",
"T. D.",
""
],
[
"Nagy",
"M.",
""
],
[
"Surovtsev",
"Yu. S.",
""
]
] | The process $\pi N\to e^+e^- N$ (IPE), being a natural and unique laboratory for studying the hadron electromagnetic structure in the sub-$N\bar{N}$-threshold time-like region of the virtual-photon ``mass'' $\lambda^2$, turns out to be also very useful for investigating the nucleon weak structure. A theoretical basis of the methods for extracting practically model-independent values of the electromagnetic hadron form factors in the time-like region and for determining the weak structure of the nucleon in the space-like region from experimental data on IPE at low energies is outlined. The results of extracting, by those methods, the electromagnetic $F_1^v(\lambda^2)$ and pseudoscalar $G_P(t)$ form-factors of a nucleon are presented, where an indication of the existence of the state $\pi^\p$ in the range 500-800 MeV (possibly the first radial excitation of pion) is obtained, and the coupling constant of this new state with the nucleon is estimated. |
0905.4079 | Matthias Burkardt | Matthias Burkardt (NMSU/Jefferson Lab) | The $g_2$ Structure Function | 9 pages, invited talk at `Spin Structure at Low $Q^2$', Jefferson
Lab, March 2009 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Polarized structure functions at low $Q^2$ have the physical interpretation
of (generalized) spin polarizabilities. At high $Q^2$, the polarized parton
distribution $g_2(x)$ provides access to quark-gluon correlations in the
nucleon. We discuss the interpretation of the $x^2$ moment of $\bar{g}_2(x)$ as
an average transverse force on quarks in deep-inelastic scattering from a
transversely polarized target. Qualitative connections with generalized parton
distributions are emphasized. The $x^2$ moment of the chirally-odd twist-3
parton distribution $e(x)$ provides information on the dependence of the
average transverse force on the transversity of the quark.
| [
{
"created": "Mon, 25 May 2009 20:18:38 GMT",
"version": "v1"
}
] | 2009-05-27 | [
[
"Burkardt",
"Matthias",
"",
"NMSU/Jefferson Lab"
]
] | Polarized structure functions at low $Q^2$ have the physical interpretation of (generalized) spin polarizabilities. At high $Q^2$, the polarized parton distribution $g_2(x)$ provides access to quark-gluon correlations in the nucleon. We discuss the interpretation of the $x^2$ moment of $\bar{g}_2(x)$ as an average transverse force on quarks in deep-inelastic scattering from a transversely polarized target. Qualitative connections with generalized parton distributions are emphasized. The $x^2$ moment of the chirally-odd twist-3 parton distribution $e(x)$ provides information on the dependence of the average transverse force on the transversity of the quark. |
1311.2541 | Michal Czakon | M. Czakon and P. Fiedler | The soft function for color octet production at threshold | 18 pages, 5 figures, references added, matches published version | Nuclear Physics B 879 (2014) 236 | 10.1016/j.nuclphysb.2013.12.008 | TTK-13-24 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We evaluate the next-to-next-to-leading order soft function for the
production of a massive color octet state at rest in the collision of two
massless colored partons in either the fundamental or the adjoint
representation. The main application of our result is the determination of the
threshold expansion of the heavy-quark pair-production cross sections in the
quark annihilation and gluon fusion channels. We discuss the factorization
necessary for this purpose and explain the relationship between hard functions
and virtual amplitudes.
| [
{
"created": "Mon, 11 Nov 2013 19:22:25 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Jan 2014 14:08:57 GMT",
"version": "v2"
}
] | 2015-06-17 | [
[
"Czakon",
"M.",
""
],
[
"Fiedler",
"P.",
""
]
] | We evaluate the next-to-next-to-leading order soft function for the production of a massive color octet state at rest in the collision of two massless colored partons in either the fundamental or the adjoint representation. The main application of our result is the determination of the threshold expansion of the heavy-quark pair-production cross sections in the quark annihilation and gluon fusion channels. We discuss the factorization necessary for this purpose and explain the relationship between hard functions and virtual amplitudes. |
2211.11697 | Lorenzo Bartolini | Lorenzo Bartolini, Sven Bjarke Gudnason, Josef Leutgeb and Anton
Rebhan | Neutron stars and phase diagram from a double hard-wall | 8 pages, 4 figures. Contribution to the proceedings of the XVth Quark
Confinement and the Hadron Spectrum, 1 to 6 August 2022, Stavanger, Norway.
Based on arXiv:2202.12845 | null | 10.1051/epjconf/202227407007 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Description of nuclear matter in the core of neutron stars eludes the main
tools of investigation of QCD, such as perturbation theory and the lattice
formulation of the theory. Recently, the application of the holographic
paradigm (both via top-down and bottom-up models) to this task has led to many
encouraging results, both qualitatively and quantitatively. We present our
approach to the description of neutron star cores, relying on a simple model of
the (double) hard-wall type: we discuss results concerning the nature of
homogeneous nuclear matter at high density emerging from the model including a
quarkyonic phase, the mass-radius relation for neutron stars, as well as the
rather stiff equation of state we have found. We show how, despite the very
simple model employed, for an appropriate calibration we are able to obtain
neutron stars that only slightly fall short of the observational bounds on
radius and tidal deformability.
| [
{
"created": "Mon, 21 Nov 2022 18:19:04 GMT",
"version": "v1"
}
] | 2023-01-11 | [
[
"Bartolini",
"Lorenzo",
""
],
[
"Gudnason",
"Sven Bjarke",
""
],
[
"Leutgeb",
"Josef",
""
],
[
"Rebhan",
"Anton",
""
]
] | Description of nuclear matter in the core of neutron stars eludes the main tools of investigation of QCD, such as perturbation theory and the lattice formulation of the theory. Recently, the application of the holographic paradigm (both via top-down and bottom-up models) to this task has led to many encouraging results, both qualitatively and quantitatively. We present our approach to the description of neutron star cores, relying on a simple model of the (double) hard-wall type: we discuss results concerning the nature of homogeneous nuclear matter at high density emerging from the model including a quarkyonic phase, the mass-radius relation for neutron stars, as well as the rather stiff equation of state we have found. We show how, despite the very simple model employed, for an appropriate calibration we are able to obtain neutron stars that only slightly fall short of the observational bounds on radius and tidal deformability. |
2208.01651 | Kazuki Sakurai | I\~naki Lara, Trygve Buanes, Rafa{\l} Mase{\l}ek, Mihoko M. Nojiri,
Krzysztof Rolbiecki and Kazuki Sakurai | Monojet signatures from gluino and squark decays | 20 pages, 10 figures. Version published in JHEP | null | 10.1007/JHEP10(2022)150 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the monojet and dijet channels at the LHC as a tool for searching
for squarks and gluinos. We consider two separate R-parity conserving
supersymmetric scenarios. In the first scenario we postulate a large mass
hierarchy between squarks ($\tilde q$) and winos ($\widetilde W$), and
wino-like neutralino is assumed to be the lightest supersymmetric particle
(LSP). The associated squark-wino production, $pp \to \tilde q \widetilde W$,
then leads to a monojet-like signature, where the high $p_T$ jet is originated
from the squark decay, $\tilde q \to q + \widetilde W$. We demonstrate that
this associated production, as well as the $pp \to \widetilde W \widetilde W +
{\rm jets}$ production, have a significant impact on the exclusion limit in the
squark-neutralino mass plane. The second scenario postulates that the lighter
of the squark and gluino is only a few GeV heavier than the LSP neutralino. The
associated squark-gluino production, $pp \to \tilde q \tilde g$, then leads to
a distinctive monojet signature, where the high $p_T$ jet is produced from the
decay of the heavier coloured particle into the lighter one ($\tilde q \to q +
\tilde g$ for $m_{\tilde q} > m_{\tilde g}$ and $\tilde g \to q + \tilde q$ for
$m_{\tilde g} > m_{\tilde q}$). The lighter coloured particle is effectively
regarded as an invisible particle since the decay products are soft due to the
approximate mass degeneracy. We recast existing monojet and dijet analyses and
find a non-trivial exclusion limit in the squark-gluino mass plane in this
scenario.
| [
{
"created": "Tue, 2 Aug 2022 18:00:00 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Oct 2022 07:15:21 GMT",
"version": "v2"
}
] | 2022-11-09 | [
[
"Lara",
"Iñaki",
""
],
[
"Buanes",
"Trygve",
""
],
[
"Masełek",
"Rafał",
""
],
[
"Nojiri",
"Mihoko M.",
""
],
[
"Rolbiecki",
"Krzysztof",
""
],
[
"Sakurai",
"Kazuki",
""
]
] | We study the monojet and dijet channels at the LHC as a tool for searching for squarks and gluinos. We consider two separate R-parity conserving supersymmetric scenarios. In the first scenario we postulate a large mass hierarchy between squarks ($\tilde q$) and winos ($\widetilde W$), and wino-like neutralino is assumed to be the lightest supersymmetric particle (LSP). The associated squark-wino production, $pp \to \tilde q \widetilde W$, then leads to a monojet-like signature, where the high $p_T$ jet is originated from the squark decay, $\tilde q \to q + \widetilde W$. We demonstrate that this associated production, as well as the $pp \to \widetilde W \widetilde W + {\rm jets}$ production, have a significant impact on the exclusion limit in the squark-neutralino mass plane. The second scenario postulates that the lighter of the squark and gluino is only a few GeV heavier than the LSP neutralino. The associated squark-gluino production, $pp \to \tilde q \tilde g$, then leads to a distinctive monojet signature, where the high $p_T$ jet is produced from the decay of the heavier coloured particle into the lighter one ($\tilde q \to q + \tilde g$ for $m_{\tilde q} > m_{\tilde g}$ and $\tilde g \to q + \tilde q$ for $m_{\tilde g} > m_{\tilde q}$). The lighter coloured particle is effectively regarded as an invisible particle since the decay products are soft due to the approximate mass degeneracy. We recast existing monojet and dijet analyses and find a non-trivial exclusion limit in the squark-gluino mass plane in this scenario. |
1704.06763 | Guo-Liang Yu | Guo Liang Yu, Zhi Gang Wang, Zhen Yu Li | The analysis of the charmonium-like states $X^{*}(3860)$,$X(3872)$,
$X(3915)$, $X(3930)$ and $X(3940)$ according to its strong decay behaviors | null | Chin.Phys.C 42 (2018) 4, 043107 | 10.1088/1674-1137/42/4/043107 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inspired by the newly observed state $X^{*}(3860)$, we analyze the strong
decay behaviors of some charmonium-like states $X^{*}(3860)$,$X(3872)$,
$X(3915)$, $X(3930)$ and $X(3940)$ by the $^{3}P_{0}$ model. We carry out our
work based on the hypothesis that these states are all being the charmonium
systems. Our analysis indicates that $0^{++}$ charmonium state can be a good
candidate for $X^{*}(3860)$ and $1^{++}$ state is the possible assignment for
$X(3872)$. Considering as the $3^{1}S_{0}$ state, the decay behavior of
$X(3940)$ is inconsistent with the experimental data. So, we can not assign
$X(3940)$ as the $3^{1}S_{0}$ charmonium state by present work. Besides, our
analysis imply that it is reasonable to assign $X(3915)$ and $X(3930)$ to be
the same state, $2^{++}$. However, combining our analysis with that of
Zhou~\cite{ZhouZY}, we speculate that $X(3915)$/$X(3930)$ might not be a pure
$c\overline{c}$ systems.
| [
{
"created": "Sat, 22 Apr 2017 08:11:21 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Apr 2017 04:08:47 GMT",
"version": "v2"
},
{
"created": "Tue, 9 May 2017 08:42:37 GMT",
"version": "v3"
}
] | 2023-04-14 | [
[
"Yu",
"Guo Liang",
""
],
[
"Wang",
"Zhi Gang",
""
],
[
"Li",
"Zhen Yu",
""
]
] | Inspired by the newly observed state $X^{*}(3860)$, we analyze the strong decay behaviors of some charmonium-like states $X^{*}(3860)$,$X(3872)$, $X(3915)$, $X(3930)$ and $X(3940)$ by the $^{3}P_{0}$ model. We carry out our work based on the hypothesis that these states are all being the charmonium systems. Our analysis indicates that $0^{++}$ charmonium state can be a good candidate for $X^{*}(3860)$ and $1^{++}$ state is the possible assignment for $X(3872)$. Considering as the $3^{1}S_{0}$ state, the decay behavior of $X(3940)$ is inconsistent with the experimental data. So, we can not assign $X(3940)$ as the $3^{1}S_{0}$ charmonium state by present work. Besides, our analysis imply that it is reasonable to assign $X(3915)$ and $X(3930)$ to be the same state, $2^{++}$. However, combining our analysis with that of Zhou~\cite{ZhouZY}, we speculate that $X(3915)$/$X(3930)$ might not be a pure $c\overline{c}$ systems. |
hep-ph/0105207 | John Collins | J.C. Collins and J. Pumplin | Tests of goodness of fit to multiple data sets | 22 pages, 8 figures | null | null | DESY-01-014 | hep-ph | null | We propose a new and rather stringent criterion for testing the goodness of
fit between a theory and experiment. It is motivated by the paradox that the
criterion on \chi^2 for testing a theory is much weaker than the criterion for
finding the best fit value of a parameter in the theory. We present a method by
which the stronger parameter-fitting criterion can be applied to subsets of
data in a global fit.
| [
{
"created": "Mon, 21 May 2001 13:13:58 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Collins",
"J. C.",
""
],
[
"Pumplin",
"J.",
""
]
] | We propose a new and rather stringent criterion for testing the goodness of fit between a theory and experiment. It is motivated by the paradox that the criterion on \chi^2 for testing a theory is much weaker than the criterion for finding the best fit value of a parameter in the theory. We present a method by which the stronger parameter-fitting criterion can be applied to subsets of data in a global fit. |
2308.10885 | Federico Coro | Matteo Becchetti, Roberto Bonciani, Leandro Cieri, Federico Coro,
Federico Ripani | Full top-quark mass dependence in diphoton production at NNLO in QCD | 8 pages and 6 figures | null | null | IFIC/23-33, FTUV-23-0808.1917 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we consider the diphoton production in hadronic collisions at
the next-to-next-to-leading order (NNLO) in perturbative QCD, taking into
account for the first time the full top quark mass dependence up to two loops
(full NNLO). We show selected numerical distributions, highlighting the
kinematic regions where the massive corrections are more significant. We make
use of the recently computed two-loop massive amplitudes for diphoton
production in the quark annihilation channel. The remaining massive
contributions at NNLO are also considered, and we comment on the weight of the
different types of contributions to the full and complete result.
| [
{
"created": "Mon, 21 Aug 2023 17:34:40 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Nov 2023 17:24:32 GMT",
"version": "v2"
}
] | 2023-12-01 | [
[
"Becchetti",
"Matteo",
""
],
[
"Bonciani",
"Roberto",
""
],
[
"Cieri",
"Leandro",
""
],
[
"Coro",
"Federico",
""
],
[
"Ripani",
"Federico",
""
]
] | In this paper we consider the diphoton production in hadronic collisions at the next-to-next-to-leading order (NNLO) in perturbative QCD, taking into account for the first time the full top quark mass dependence up to two loops (full NNLO). We show selected numerical distributions, highlighting the kinematic regions where the massive corrections are more significant. We make use of the recently computed two-loop massive amplitudes for diphoton production in the quark annihilation channel. The remaining massive contributions at NNLO are also considered, and we comment on the weight of the different types of contributions to the full and complete result. |
1302.5152 | Masashi Wakamatsu | Masashi Wakamatsu | Are there infinitely many decompositions of the nucleon spin ? | 37 pages, 5 figures, Version to appear in Physical Review D. The
logic of the whole argument in the paper was drastically changed. The
delicacy of the gauge-invariant but the path-dependent formulation of gauge
theories is discussed in some detail | null | 10.1103/PhysRevD.87.094035 | OU-HET-777 | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the uniqueness or non-uniqueness problem of the decomposition of
the gluon field into the physical and pure-gauge components, which is the basis
of the recently proposed two physically inequivalent gauge-invariant
decompositions of the nucleon spin. It is crucialy important to recognize the
fact that the standard gauge fixing procedure is essentially a process of
projecting out the physical components of the massless gauge field. A
complexity of the nonabelian gauge theory as compared with the abelian case is
that a closed expression for the physical component can be given only with use
of the non-local Wilson line, which is generally path-dependent. It is known
that, by choosing an infinitely long straight-line path in space and time, the
direction of which is characterized by a constant 4-vector $n^\mu$, one can
cover a class of gauge called the general axial gauge, containing three popular
gauges, i.e. the temporal, the light-cone, and the spatial axial gauge. Within
this general axial gauge, we have calculated the 1-loop evolution matrix for
the quark and gluon longitudinal spins in the nucleon. We found that the final
answer is exactly the same independently of the choices of $n^\mu$, which
amounts to proving the gauge-independence and path-independence simultaneously,
although within a restricted class of gauges and paths. By drawing on all of
these findings together with well-established knowledge from gauge theories, we
argue against the rapidly spreading view in the community that there are
infinitely many decompositions of the nucleon spin.
| [
{
"created": "Thu, 21 Feb 2013 00:39:46 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Mar 2013 01:16:33 GMT",
"version": "v2"
},
{
"created": "Fri, 24 May 2013 00:53:17 GMT",
"version": "v3"
}
] | 2015-06-15 | [
[
"Wakamatsu",
"Masashi",
""
]
] | We discuss the uniqueness or non-uniqueness problem of the decomposition of the gluon field into the physical and pure-gauge components, which is the basis of the recently proposed two physically inequivalent gauge-invariant decompositions of the nucleon spin. It is crucialy important to recognize the fact that the standard gauge fixing procedure is essentially a process of projecting out the physical components of the massless gauge field. A complexity of the nonabelian gauge theory as compared with the abelian case is that a closed expression for the physical component can be given only with use of the non-local Wilson line, which is generally path-dependent. It is known that, by choosing an infinitely long straight-line path in space and time, the direction of which is characterized by a constant 4-vector $n^\mu$, one can cover a class of gauge called the general axial gauge, containing three popular gauges, i.e. the temporal, the light-cone, and the spatial axial gauge. Within this general axial gauge, we have calculated the 1-loop evolution matrix for the quark and gluon longitudinal spins in the nucleon. We found that the final answer is exactly the same independently of the choices of $n^\mu$, which amounts to proving the gauge-independence and path-independence simultaneously, although within a restricted class of gauges and paths. By drawing on all of these findings together with well-established knowledge from gauge theories, we argue against the rapidly spreading view in the community that there are infinitely many decompositions of the nucleon spin. |
0807.0612 | Rafael Porto | Rafael A. Porto and A. Zee | Neutrino Mixing and the Private Higgs | 24 pages. 4 figures | Phys.Rev.D79:013003,2009 | 10.1103/PhysRevD.79.013003 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We extend the Private Higgs scenario to account for charged lepton and
neutrino masses by introducing a private Higgs field for each lepton family. We
analyze a model in which neutrino Majorana masses are radiatively induced.
Contrary to previous models the neutrino mass scale ~ 10^{-2} eV is naturally
obtained without excessive fine tunings. The model requires the introduction of
SU(2) singlet scalar fields, two charged and one neutral. We discuss a possible
realization giving a normal neutrino mass hierarchy. Our model fits data and
predicts a non-zero V_{e3}.
| [
{
"created": "Thu, 3 Jul 2008 18:48:25 GMT",
"version": "v1"
}
] | 2009-01-21 | [
[
"Porto",
"Rafael A.",
""
],
[
"Zee",
"A.",
""
]
] | We extend the Private Higgs scenario to account for charged lepton and neutrino masses by introducing a private Higgs field for each lepton family. We analyze a model in which neutrino Majorana masses are radiatively induced. Contrary to previous models the neutrino mass scale ~ 10^{-2} eV is naturally obtained without excessive fine tunings. The model requires the introduction of SU(2) singlet scalar fields, two charged and one neutral. We discuss a possible realization giving a normal neutrino mass hierarchy. Our model fits data and predicts a non-zero V_{e3}. |
1604.02382 | Lauren Pearce | Alexander Kusenko, Lauren Pearce, and Louis Yang | Leptogenesis via the 750 GeV pseudoscalar | 9 pages, 4 figures | Phys. Rev. D 93, 115005 (2016) | 10.1103/PhysRevD.93.115005 | FTPI-MINN-16/12 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently the ATLAS and CMS collaborations have reported evidence of a
diphoton excess which may be interpreted as a pseudoscalar boson S with a mass
around 750 GeV. To explain the diphoton excess, such a boson is coupled to the
Standard Model gauge fields via SFF-dual operators. In this work, we consider
the implications of this state for early universe cosmology; in particular, the
S field can acquire a large vacuum expectation value due to quantum
fluctuations during inflation. During reheating, it then relaxes to its
equilibrium value, during which time the same operators introduced to explain
the diphoton excess induce a nonzero chemical potential for baryon and lepton
number. Interactions such as those involving right-handed neutrinos allow the
system to develop a non-zero lepton number, and therefore, this state may also
be responsible for the observed cosmological matter-antimatter asymmetry.
| [
{
"created": "Fri, 8 Apr 2016 15:50:15 GMT",
"version": "v1"
},
{
"created": "Thu, 19 May 2016 22:00:17 GMT",
"version": "v2"
}
] | 2016-06-15 | [
[
"Kusenko",
"Alexander",
""
],
[
"Pearce",
"Lauren",
""
],
[
"Yang",
"Louis",
""
]
] | Recently the ATLAS and CMS collaborations have reported evidence of a diphoton excess which may be interpreted as a pseudoscalar boson S with a mass around 750 GeV. To explain the diphoton excess, such a boson is coupled to the Standard Model gauge fields via SFF-dual operators. In this work, we consider the implications of this state for early universe cosmology; in particular, the S field can acquire a large vacuum expectation value due to quantum fluctuations during inflation. During reheating, it then relaxes to its equilibrium value, during which time the same operators introduced to explain the diphoton excess induce a nonzero chemical potential for baryon and lepton number. Interactions such as those involving right-handed neutrinos allow the system to develop a non-zero lepton number, and therefore, this state may also be responsible for the observed cosmological matter-antimatter asymmetry. |
hep-ph/0702222 | Dmitry Naumov | John Ellis, Aram Kotzinian, Dmitry Naumov and Mikhail Sapozhnikov | Longitudinal Polarization of Lambda and anti-Lambda Hyperons in
Lepton-Nucleon Deep-Inelastic Scattering | minor changes after accepted to EPJC | Eur.Phys.J.C52:283-294,2007 | 10.1140/epjc/s10052-007-0381-9 | null | hep-ph | null | We consider models for the spin transfers to $\Lambda$ and $\bar{\Lambda}$
hyperons produced in lepton-nucleon deep-inelastic scattering. We make
predictions for longitudinal $\Lambda$ and $\bar{\Lambda}$ spin transfers for
the COMPASS experiment and for HERA, and for the spin transfer to $\Lambda$
hyperons produced at JLAB. We demonstrate that accurate measurements of the
spin transfers to $\Lambda$ and $\bar{\Lambda}$ hyperons with COMPASS
kinematics have the potential to probe the intrinsic strangeness in the
nucleon. We show that a measurement of $\bar{\Lambda}$ polarisation could
provide a clean probe of the spin transfer from $\bar{s}$ quarks and provides a
new possibility to measure the antistrange quark distribution function. COMPASS
data in a domain of x that has not been studied previously will provide
valuable extra information to fix models for the nucleon spin structure. The
spin transfer to $\bar{\Lambda}$ hyperons, which could be measured by the
COMPASS experiment, would provide a new tool to distinguish between the SU(6)
and Burkardt-Jaffe (BJ) models for baryon spin structure. In the case of the
HERA electron-proton collider experiments with longitudinally-polarised
electrons, the separation between the target and current fragmentation
mechanisms is more clear. It provides a complementary probe of the strange
quark distribution and helps distinguish between the SU(6) and BJ models for
the $\Lambda$ and $\bar{\Lambda}$ spin structure. Finally, we show that the
spin transfer to $\Lambda$ hyperons measured in a JLAB experiment would be
dominated by the spin transfer of the intrinsic polarised-strangeness in the
remnant nucleon, providing an independent way to check our model predictions.
| [
{
"created": "Wed, 21 Feb 2007 18:45:59 GMT",
"version": "v1"
},
{
"created": "Wed, 10 Oct 2007 08:23:09 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Ellis",
"John",
""
],
[
"Kotzinian",
"Aram",
""
],
[
"Naumov",
"Dmitry",
""
],
[
"Sapozhnikov",
"Mikhail",
""
]
] | We consider models for the spin transfers to $\Lambda$ and $\bar{\Lambda}$ hyperons produced in lepton-nucleon deep-inelastic scattering. We make predictions for longitudinal $\Lambda$ and $\bar{\Lambda}$ spin transfers for the COMPASS experiment and for HERA, and for the spin transfer to $\Lambda$ hyperons produced at JLAB. We demonstrate that accurate measurements of the spin transfers to $\Lambda$ and $\bar{\Lambda}$ hyperons with COMPASS kinematics have the potential to probe the intrinsic strangeness in the nucleon. We show that a measurement of $\bar{\Lambda}$ polarisation could provide a clean probe of the spin transfer from $\bar{s}$ quarks and provides a new possibility to measure the antistrange quark distribution function. COMPASS data in a domain of x that has not been studied previously will provide valuable extra information to fix models for the nucleon spin structure. The spin transfer to $\bar{\Lambda}$ hyperons, which could be measured by the COMPASS experiment, would provide a new tool to distinguish between the SU(6) and Burkardt-Jaffe (BJ) models for baryon spin structure. In the case of the HERA electron-proton collider experiments with longitudinally-polarised electrons, the separation between the target and current fragmentation mechanisms is more clear. It provides a complementary probe of the strange quark distribution and helps distinguish between the SU(6) and BJ models for the $\Lambda$ and $\bar{\Lambda}$ spin structure. Finally, we show that the spin transfer to $\Lambda$ hyperons measured in a JLAB experiment would be dominated by the spin transfer of the intrinsic polarised-strangeness in the remnant nucleon, providing an independent way to check our model predictions. |
2311.10139 | Oleksii Matsedonskyi | Oleksii Matsedonskyi | Hierarchies from Landscape Probability Gradients and Critical Boundaries | 38 pages, 9 figures | null | null | TUM-HEP 1482/23 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | If the gradient of a probability distribution on a landscape of vacua aligns
with the variation of some fundamental parameter, the parameter may be likely
to take some non-generic value. Such non-generic values can be associated to
critical boundaries, where qualitative changes of the landscape properties
happen, or an anthropic bound is located. Assuming the standard volume-weighted
and the local probability measures, we discuss ordered landscapes which can
produce several types of the aligned probability gradients. The resulting
values of the gradients are defined by the "closeness" of a given vacuum to the
highest- or the lowest-energy vacuum. Using these ingredients we construct a
landscape scanning independently the Higgs mass and the cosmological constant
(CC). The probability gradient pushes the Higgs mass to its observed value,
where a structural change of the landscape takes place, while the CC is chosen
anthropically.
| [
{
"created": "Thu, 16 Nov 2023 19:00:02 GMT",
"version": "v1"
}
] | 2023-11-20 | [
[
"Matsedonskyi",
"Oleksii",
""
]
] | If the gradient of a probability distribution on a landscape of vacua aligns with the variation of some fundamental parameter, the parameter may be likely to take some non-generic value. Such non-generic values can be associated to critical boundaries, where qualitative changes of the landscape properties happen, or an anthropic bound is located. Assuming the standard volume-weighted and the local probability measures, we discuss ordered landscapes which can produce several types of the aligned probability gradients. The resulting values of the gradients are defined by the "closeness" of a given vacuum to the highest- or the lowest-energy vacuum. Using these ingredients we construct a landscape scanning independently the Higgs mass and the cosmological constant (CC). The probability gradient pushes the Higgs mass to its observed value, where a structural change of the landscape takes place, while the CC is chosen anthropically. |
hep-ph/9401208 | Jim Cline | James M. Cline, Kimmo Kainulainen and Keith A. Olive | Protecting the Primordial Baryon Asymmetry From Erasure by Sphalerons | 41 pp., 4 latex figures included and 3 uuencoded or postscript
figures available by request, UMN-TH-1213-93 | Phys.Rev.D49:6394-6409,1994 | 10.1103/PhysRevD.49.6394 | null | hep-ph | null | If the baryon asymmetry of the universe was created at the GUT scale,
sphalerons together with exotic sources of $(B-L)$-violation could have erased
it, unless the latter satisfy stringent bounds. We elaborate on how the small
Yukawa coupling of the electron drastically weakens previous estimates of these
bounds.
| [
{
"created": "Wed, 5 Jan 1994 19:56:40 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Cline",
"James M.",
""
],
[
"Kainulainen",
"Kimmo",
""
],
[
"Olive",
"Keith A.",
""
]
] | If the baryon asymmetry of the universe was created at the GUT scale, sphalerons together with exotic sources of $(B-L)$-violation could have erased it, unless the latter satisfy stringent bounds. We elaborate on how the small Yukawa coupling of the electron drastically weakens previous estimates of these bounds. |
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