id stringlengths 9 14 | submitter stringlengths 1 56 ⌀ | authors stringlengths 5 7.68k | title stringlengths 3 299 | comments stringlengths 1 1.15k ⌀ | journal-ref stringlengths 9 298 ⌀ | doi stringlengths 12 97 ⌀ | report-no stringlengths 3 341 ⌀ | categories stringclasses 869 values | license stringclasses 9 values | orig_abstract stringlengths 16 2.44k | versions listlengths 1 39 | update_date stringlengths 10 10 | authors_parsed listlengths 1 565 | abstract stringlengths 13 2.44k |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0809.0705 | Jae-hyeon Park | P. Ko and Jae-hyeon Park | Implications of the measurements of B_s - B_s bar mixing on SUSY models | 29 pages | Phys.Rev.D80:035019,2009 | 10.1103/PhysRevD.80.035019 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive constraints on the mass insertion parameters from the recent
measurements of B_s - B_s bar mixing, and discuss their implications on SUSY
breaking mediation mechanisms and SUSY flavor models. Some SUSY flavor models
are already excluded or disfavored by B_s - B_s bar mixing. We also discuss how
to test the SM and SUSY models in the future experiments, by studying other CP
violating observables related to b -> s transition, such as the time-dependent
CP asymmetry in B -> phi K_S and the direct CP asymmetry in B -> X_s gamma.
| [
{
"created": "Wed, 3 Sep 2008 20:39:43 GMT",
"version": "v1"
}
] | 2009-09-01 | [
[
"Ko",
"P.",
""
],
[
"Park",
"Jae-hyeon",
""
]
] | We derive constraints on the mass insertion parameters from the recent measurements of B_s - B_s bar mixing, and discuss their implications on SUSY breaking mediation mechanisms and SUSY flavor models. Some SUSY flavor models are already excluded or disfavored by B_s - B_s bar mixing. We also discuss how to test the SM and SUSY models in the future experiments, by studying other CP violating observables related to b -> s transition, such as the time-dependent CP asymmetry in B -> phi K_S and the direct CP asymmetry in B -> X_s gamma. |
1112.5857 | Jialun Ping | Hongxia Huang, Jialun Ping and Fan Wang | Study of $p\bar{\Lambda}$ and $p\bar{\Sigma}$ systems in constituent
quark models | 7 pages, 3 figures | null | 10.1142/S0217732312500393 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $p\bar{\Lambda}$ systems with J=0 and J=1 are dynamically investigated
within the framework of two constituent quark models: the chiral quark model
and the quark delocalization color screening model. The model parameters are
taken from our previous work, which gave a good description of the
proton-antiproton S-wave elastic scattering cross section experimental data.
The $p\bar{\Lambda}$ elastic scattering processes with coupling to
$p\bar{\Sigma}$ state are studied. The results show that, there is no s-wave
bound state as indicated by an enhancement near the threshold of
$p\bar{\Lambda}$ in $J/\psi$ decay. However, a $IJ = {1/2}0$ $p\bar{\Sigma}$
resonance state is given in the quark delocalization color screening model.
| [
{
"created": "Mon, 26 Dec 2011 13:55:54 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Huang",
"Hongxia",
""
],
[
"Ping",
"Jialun",
""
],
[
"Wang",
"Fan",
""
]
] | The $p\bar{\Lambda}$ systems with J=0 and J=1 are dynamically investigated within the framework of two constituent quark models: the chiral quark model and the quark delocalization color screening model. The model parameters are taken from our previous work, which gave a good description of the proton-antiproton S-wave elastic scattering cross section experimental data. The $p\bar{\Lambda}$ elastic scattering processes with coupling to $p\bar{\Sigma}$ state are studied. The results show that, there is no s-wave bound state as indicated by an enhancement near the threshold of $p\bar{\Lambda}$ in $J/\psi$ decay. However, a $IJ = {1/2}0$ $p\bar{\Sigma}$ resonance state is given in the quark delocalization color screening model. |
1710.01684 | Jean-Philippe Lansberg | Jean-Philippe Lansberg, Cristian Pisano, Florent Scarpa, Marc Schlegel | Pinning down the linearly-polarised gluons inside unpolarised protons
using quarkonium-pair production at the LHC | v2: 8 pages, 7 figures, uses LaTeX with elsarticle. v2 matches the
published version in PLB up to a numerical mistake and mislabellings in Figs.
4 which are the object of a submitted corrigendum | Phys.Lett. B784 (2018) 217-222 | 10.1016/j.physletb.2018.08.004 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that the production of J/psi or Upsilon pairs in unpolarised pp
collisions is currently the best process to measure the momentum-distribution
of linearly-polarised gluons inside unpolarised protons through the study of
azimuthal asymmetries. Not only the short-distance coefficients for such
reactions induce the largest possible cos 4 phi modulations, but analysed data
are already available. Among the various final states previously studied in
unpolarised pp collisions within the TMD factorisation approach, di-J/psi
production exhibits by far the largest asymmetries, up to 50% in the region
studied by the ATLAS and CMS experiments. In addition, we use the very recent
LHCb data at 13 TeV to perform the first fit of the unpolarised
transverse-momentum-dependent gluon distribution.
| [
{
"created": "Wed, 4 Oct 2017 16:37:10 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Jan 2019 17:46:18 GMT",
"version": "v2"
}
] | 2019-01-30 | [
[
"Lansberg",
"Jean-Philippe",
""
],
[
"Pisano",
"Cristian",
""
],
[
"Scarpa",
"Florent",
""
],
[
"Schlegel",
"Marc",
""
]
] | We show that the production of J/psi or Upsilon pairs in unpolarised pp collisions is currently the best process to measure the momentum-distribution of linearly-polarised gluons inside unpolarised protons through the study of azimuthal asymmetries. Not only the short-distance coefficients for such reactions induce the largest possible cos 4 phi modulations, but analysed data are already available. Among the various final states previously studied in unpolarised pp collisions within the TMD factorisation approach, di-J/psi production exhibits by far the largest asymmetries, up to 50% in the region studied by the ATLAS and CMS experiments. In addition, we use the very recent LHCb data at 13 TeV to perform the first fit of the unpolarised transverse-momentum-dependent gluon distribution. |
hep-ph/9807457 | Shinohara Tadatomi | Tadatomi Shinohara (Kyoto Sangyo University), Hajime Tanaka (Kyoto
Sangyo University) and Ikuo S. Sogami (Kyoto Sangyo University and CERN) | Universal Seesaw Mechanism with Universal Strength for Yukawa Couplings | Latex, 16 pages, no figures | Prog.Theor.Phys. 100 (1998) 615-625 | 10.1143/PTP.100.615 | null | hep-ph | null | Hypotheses of the universal seesaw mechanism and the {\it universal strength
for Yukawa couplings} are applied to explain one possible origin of
quasi-democratic mass matrices of a special type in a left-right symmetric
model with the gauge group $SU(3)_c\times SU(2)_L\times SU(2)_R\times U(1)$.
Two kinds of Higgs doublets are postulated to mediate scalar interactions
between the $i$-th generation of light fermion doublets and the $j$-th
generation of heavy fermion singlets with relative Yukawa coupling constants of
the exponential form $e^{i\phi_{ij}}$, where $\phi_{ij}$ are real phase
constants. The lowest seesaw approximation results effectively in self-adjoint
mass matrices which are quasi-democratic and have the same diagonal elements. A
set of values for the parameters $\phi_{ij}$ is found which reproduces the
present experimental data for the absolute values of the CKM matrix elements,
the Jarlskog parameter and the Wolfenstein parameters.
| [
{
"created": "Wed, 22 Jul 1998 08:57:54 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Nov 1998 10:51:11 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Shinohara",
"Tadatomi",
"",
"Kyoto Sangyo University"
],
[
"Tanaka",
"Hajime",
"",
"Kyoto\n Sangyo University"
],
[
"Sogami",
"Ikuo S.",
"",
"Kyoto Sangyo University and CERN"
]
] | Hypotheses of the universal seesaw mechanism and the {\it universal strength for Yukawa couplings} are applied to explain one possible origin of quasi-democratic mass matrices of a special type in a left-right symmetric model with the gauge group $SU(3)_c\times SU(2)_L\times SU(2)_R\times U(1)$. Two kinds of Higgs doublets are postulated to mediate scalar interactions between the $i$-th generation of light fermion doublets and the $j$-th generation of heavy fermion singlets with relative Yukawa coupling constants of the exponential form $e^{i\phi_{ij}}$, where $\phi_{ij}$ are real phase constants. The lowest seesaw approximation results effectively in self-adjoint mass matrices which are quasi-democratic and have the same diagonal elements. A set of values for the parameters $\phi_{ij}$ is found which reproduces the present experimental data for the absolute values of the CKM matrix elements, the Jarlskog parameter and the Wolfenstein parameters. |
hep-ph/9605329 | Subir Mohan | Subir Mohan | GUT's have the ability to defy sphalerons | 13 pages, Latex File | Phys.Lett.B389:551-556,1996 | 10.1016/S0370-2693(96)01301-9 | MRI preprint MRI/PHY-130/96 | hep-ph | null | We show that the baryon asymmetry produced by the out of equilibrium decay of
heavy $GUT$ scalars can be the baryon asymmetry that is observed today. No
restrictions need be imposed on the initial values of $B$, $L$ and $B-L$, nor
on the neutrino masses; no new symmetries need be gauged nor new fermions
introduced. We find two mechanisms that can bring this about for any $GUT$
gauge group. Two illustrative models are discussed that are robust, and need
just two (at most four) more $GUT$ scalar fields than the minimum model. The
additional scalar fields can also help in generating an adequately large value
of the CP violation parameter and in efficiently annihilating the monopoles.
Our work should firmly re-establish heavy $GUT$ scalars as probable progenitors
of today's baryon asymmetry.
| [
{
"created": "Thu, 16 May 1996 10:41:38 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Mohan",
"Subir",
""
]
] | We show that the baryon asymmetry produced by the out of equilibrium decay of heavy $GUT$ scalars can be the baryon asymmetry that is observed today. No restrictions need be imposed on the initial values of $B$, $L$ and $B-L$, nor on the neutrino masses; no new symmetries need be gauged nor new fermions introduced. We find two mechanisms that can bring this about for any $GUT$ gauge group. Two illustrative models are discussed that are robust, and need just two (at most four) more $GUT$ scalar fields than the minimum model. The additional scalar fields can also help in generating an adequately large value of the CP violation parameter and in efficiently annihilating the monopoles. Our work should firmly re-establish heavy $GUT$ scalars as probable progenitors of today's baryon asymmetry. |
0705.2290 | Patricia Ball | Patricia Ball | |V_{ub}| from the Spectrum of B->pi e nu | Proceedings of FPCP07, Bled, Slovenia | ECONFC070512:016,2007 | null | IPPP/07/19 | hep-ph | null | I discuss the results for $|V_{ub}|f_+(0)$ and $|V_{ub}|$ obtained from the
spectrum of $B\to\pi e \nu$ and the form factor $f_+(q^2)$ from QCD sum rules
on the light-cone and unquenched lattice calculations; the shape of $f_+(q^2)$
is fixed from experimental data.
| [
{
"created": "Wed, 16 May 2007 07:49:26 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Ball",
"Patricia",
""
]
] | I discuss the results for $|V_{ub}|f_+(0)$ and $|V_{ub}|$ obtained from the spectrum of $B\to\pi e \nu$ and the form factor $f_+(q^2)$ from QCD sum rules on the light-cone and unquenched lattice calculations; the shape of $f_+(q^2)$ is fixed from experimental data. |
hep-ph/0107106 | Andrei Shuvaev | Yu. M. Shabelski and A. G. Shuvaev (PNPI, Gatchina, Russia) | Heavy quark hadroproduction in k_T-factorization approach and the
experimental data | 13 pages, LaTeX, 12 PostScript figures | null | null | null | hep-ph | null | We compare the numerical predictions of the k_T-factorization approach
(semihard theory) for heavy quark production in high energy nucleon-nucleon and
photon-nucleon collisions with the experimental data from Tevatron-collider and
HERA. Predictions for heavy quark production at Tevatron, LHC and HERA are also
presented.
| [
{
"created": "Tue, 10 Jul 2001 06:20:10 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Shabelski",
"Yu. M.",
"",
"PNPI, Gatchina, Russia"
],
[
"Shuvaev",
"A. G.",
"",
"PNPI, Gatchina, Russia"
]
] | We compare the numerical predictions of the k_T-factorization approach (semihard theory) for heavy quark production in high energy nucleon-nucleon and photon-nucleon collisions with the experimental data from Tevatron-collider and HERA. Predictions for heavy quark production at Tevatron, LHC and HERA are also presented. |
hep-ph/9908520 | Adam Falk | Adam F. Falk | B Decays, the Unitarity Triangle, and the Universe | 25 pages, 3 EPS figures; to appear in the Proceedings of the XIX
International Symposium on Lepton and Photon Interactions at High Energies;
portions of article reformatted to conform to guidelines for published
proceedings | Int.J.Mod.Phys.A15S1:174-198,2000; eConf C990809:174-198,2000 | null | null | hep-ph | null | A review is given of recent developments in the physics of flavor. Current
constraints on the Cabibbo-Kobayashi-Maskawa matrix are discussed and related
to the recent measurements of epsilon'/epsilon, sin(2beta) and K+ -> pi+ nu
nubar. A brief review is given of the connection between CP violation in B
decays and electroweak baryogenesis. Finally, there is an extensive discussion
of how present and proposed experiments in K and B physics can constrain the
pattern of flavor changing processes at low energies and, one hopes, eventually
provide unambiguous evidence of physics beyond the Standard Model.
| [
{
"created": "Tue, 31 Aug 1999 15:58:57 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Sep 1999 16:57:53 GMT",
"version": "v2"
},
{
"created": "Tue, 7 Sep 1999 16:19:49 GMT",
"version": "v3"
},
{
"created": "Mon, 27 Sep 1999 15:58:30 GMT",
"version": "v4"
}
] | 2011-03-23 | [
[
"Falk",
"Adam F.",
""
]
] | A review is given of recent developments in the physics of flavor. Current constraints on the Cabibbo-Kobayashi-Maskawa matrix are discussed and related to the recent measurements of epsilon'/epsilon, sin(2beta) and K+ -> pi+ nu nubar. A brief review is given of the connection between CP violation in B decays and electroweak baryogenesis. Finally, there is an extensive discussion of how present and proposed experiments in K and B physics can constrain the pattern of flavor changing processes at low energies and, one hopes, eventually provide unambiguous evidence of physics beyond the Standard Model. |
1207.2330 | Guillermo R\'ios M\'arquez | Guillermo Rios, Jenifer Nebreda, Jose R. Pelaez | Enhanced non-quark-antiquark and non-gluebal N_c behavior of light
scalar mesons | To appear in the proceedings of the sixth international conference on
Quark and Nuclear Physics QNP2012, April 16 - 20 2012, Palaiseau (France) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We report our results on the nature of the lightest scalar resonances, where
we show that a quark-antiquark or glueball interpretation of the scalars
f_0(600) and K^*_0(800) requires a very unnatural fine tuning to satisfy
1/N_c-expansion predictions for quark-antiquark or glueball states, which is
not needed in the case of the lightest vector mesons \rho(770) and K^*(892).
For this we consider scattering observables whose value is fixed to 1 for
quark-antiquark and glueball states up to corrections suppressed by more than
one power of 1/N_c, thus enhancing contributions of other nature. This allows
us to evaluate these observables and check the 1/N_c predictions at N_c=3
without the need to extrapolate to unphysical N_c values. This is done using
recent and very precise dispersive \pi\pi and \pi K scattering data analyses.
| [
{
"created": "Tue, 10 Jul 2012 12:29:30 GMT",
"version": "v1"
}
] | 2012-07-11 | [
[
"Rios",
"Guillermo",
""
],
[
"Nebreda",
"Jenifer",
""
],
[
"Pelaez",
"Jose R.",
""
]
] | We report our results on the nature of the lightest scalar resonances, where we show that a quark-antiquark or glueball interpretation of the scalars f_0(600) and K^*_0(800) requires a very unnatural fine tuning to satisfy 1/N_c-expansion predictions for quark-antiquark or glueball states, which is not needed in the case of the lightest vector mesons \rho(770) and K^*(892). For this we consider scattering observables whose value is fixed to 1 for quark-antiquark and glueball states up to corrections suppressed by more than one power of 1/N_c, thus enhancing contributions of other nature. This allows us to evaluate these observables and check the 1/N_c predictions at N_c=3 without the need to extrapolate to unphysical N_c values. This is done using recent and very precise dispersive \pi\pi and \pi K scattering data analyses. |
0906.1652 | Aldo Deandrea | Alan S. Cornell, Aldo Deandrea, Naveen Gaur, Hideo Itoh, Michael
Klasen, Yasuhiro Okada | Universality test of the charged Higgs boson couplings at the LHC and at
B factories | 20 pages, 7 figures, LaTeX (style changed to PRD format, text
expanded, references added) | Phys.Rev.D81:115008,2010 | 10.1103/PhysRevD.81.115008 | KEK-TH-1315, LPSC 09-065, LYCEN 2009-06 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Many extensions of the Standard Model (SM) of particle physics predict the
existence of charged Higgs bosons with substantial couplings to SM particles,
which would render them observable both directly at the LHC and indirectly at
B-factories. For example, the charged Higgs boson couplings to fermions in two
doublet Higgs models of type II, are proportional to the ratio of the two Higgs
doublet vacuum expectation values (tan(beta)) and fermionic mass factors and
could thus be substantial at large tan(beta) and/or for heavy fermions. In this
work we perform a model-independent study of the charged Higgs boson couplings
at the LHC and at B-factories for large values of tan(beta). We have shown that
at high luminosity it is possible to measure the couplings of a charged Higgs
boson to the third generation of quarks up to an accuracy of 10%. We further
argue that by combining the possible measurements of the LHC and the
B-factories, it is possible to perform a universality test of charged Higgs
boson couplings to quarks.
| [
{
"created": "Tue, 9 Jun 2009 08:02:48 GMT",
"version": "v1"
},
{
"created": "Fri, 28 May 2010 08:33:29 GMT",
"version": "v2"
}
] | 2015-05-13 | [
[
"Cornell",
"Alan S.",
""
],
[
"Deandrea",
"Aldo",
""
],
[
"Gaur",
"Naveen",
""
],
[
"Itoh",
"Hideo",
""
],
[
"Klasen",
"Michael",
""
],
[
"Okada",
"Yasuhiro",
""
]
] | Many extensions of the Standard Model (SM) of particle physics predict the existence of charged Higgs bosons with substantial couplings to SM particles, which would render them observable both directly at the LHC and indirectly at B-factories. For example, the charged Higgs boson couplings to fermions in two doublet Higgs models of type II, are proportional to the ratio of the two Higgs doublet vacuum expectation values (tan(beta)) and fermionic mass factors and could thus be substantial at large tan(beta) and/or for heavy fermions. In this work we perform a model-independent study of the charged Higgs boson couplings at the LHC and at B-factories for large values of tan(beta). We have shown that at high luminosity it is possible to measure the couplings of a charged Higgs boson to the third generation of quarks up to an accuracy of 10%. We further argue that by combining the possible measurements of the LHC and the B-factories, it is possible to perform a universality test of charged Higgs boson couplings to quarks. |
2407.19782 | Andras Patkos | Andr\'as Patk\'os | Axion halo around a binary system of dwarf stars | Contribution to Procs. of Bolyai-Gauss-Lobachevsky 2024 Conference.
To appear in Ukrainian Journal of Physics vol. 69, No.7 | null | null | null | hep-ph astro-ph.SR | http://creativecommons.org/licenses/by/4.0/ | The gravitational field of a clump of ultralight axion like particles (ALPs)
in its core with a rotating binary system of dwarf stars is computed. It is
established that the induced quadrupole mass moment of the clump is controlled
parametrically by the $M_a/M$ mass ratio of the axion clump and the the binary
core.
| [
{
"created": "Mon, 29 Jul 2024 08:25:38 GMT",
"version": "v1"
}
] | 2024-07-30 | [
[
"Patkós",
"András",
""
]
] | The gravitational field of a clump of ultralight axion like particles (ALPs) in its core with a rotating binary system of dwarf stars is computed. It is established that the induced quadrupole mass moment of the clump is controlled parametrically by the $M_a/M$ mass ratio of the axion clump and the the binary core. |
1602.05068 | Gilberto Ramalho | G. Ramalho | A Relativistic Model for the Electromagnetic Structure of Baryons from
the 3rd Resonance Region | Proceedings of the ECT* Workshop "Nucleon Resonances: From
Photoproduction to High Photon Virtualities", October 12-16, 2015, Trento,
Italy. Final version. 9 pages, 6 figures, 2 tables. arXiv admin note: text
overlap with arXiv:1509.08436 | null | 10.1007/s00601-016-1154-5 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present some predictions for the $\gamma^\ast N \to N^\ast$ transition
amplitudes, where $N$ is the nucleon, and $N^\ast$ is a nucleon excitation from
the third resonance region. First we estimate the transition amplitudes
associated with the second radial excitation of the nucleon, interpreted as the
$N(1710)$ state, using the covariant spectator quark model. After that, we
combine some results from the covariant spectator quark model with the
framework of the single quark transition model, to make predictions for the
$\gamma^\ast N \to N^\ast$ transition amplitudes, where $N^\ast$ is a member of
the $SU(6)$-multiplet $[70,1^-]$. The results for the $\gamma^\ast N \to
N(1520)$ and $\gamma^\ast N \to N(1535)$ transition amplitudes are used as
input to the calculation of the amplitudes $A_{1/2}$, $A_{3/2}$, associated
with the $\gamma^\ast N \to N(1650)$, $\gamma^\ast N \to N(1700)$, $\gamma^\ast
N \to \Delta(1620)$, and $\gamma^\ast N \to \Delta(1700)$ transitions. Our
estimates are compared with the available data. In order to facilitate the
comparison with future experimental data at high $Q^2$, we derived also simple
parametrizations for the amplitudes, compatible with the expected falloff at
high $Q^2$.
| [
{
"created": "Tue, 16 Feb 2016 16:04:19 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Sep 2016 17:13:46 GMT",
"version": "v2"
}
] | 2016-09-27 | [
[
"Ramalho",
"G.",
""
]
] | We present some predictions for the $\gamma^\ast N \to N^\ast$ transition amplitudes, where $N$ is the nucleon, and $N^\ast$ is a nucleon excitation from the third resonance region. First we estimate the transition amplitudes associated with the second radial excitation of the nucleon, interpreted as the $N(1710)$ state, using the covariant spectator quark model. After that, we combine some results from the covariant spectator quark model with the framework of the single quark transition model, to make predictions for the $\gamma^\ast N \to N^\ast$ transition amplitudes, where $N^\ast$ is a member of the $SU(6)$-multiplet $[70,1^-]$. The results for the $\gamma^\ast N \to N(1520)$ and $\gamma^\ast N \to N(1535)$ transition amplitudes are used as input to the calculation of the amplitudes $A_{1/2}$, $A_{3/2}$, associated with the $\gamma^\ast N \to N(1650)$, $\gamma^\ast N \to N(1700)$, $\gamma^\ast N \to \Delta(1620)$, and $\gamma^\ast N \to \Delta(1700)$ transitions. Our estimates are compared with the available data. In order to facilitate the comparison with future experimental data at high $Q^2$, we derived also simple parametrizations for the amplitudes, compatible with the expected falloff at high $Q^2$. |
1711.00676 | Thomas Rauh | Martin Beneke, Andreas Maier, Thomas Rauh and Pedro Ruiz-Femen\'ia | Electroweak and non-resonant corrections to top-pair production near
threshold at NNLO | 8 pages, 4 figures. contribution to the 13th International Symposium
on Radiative Corrections (RADCOR 2017) | null | null | TUM-HEP-1105/17, IPPP/17/81, FTUAM-17-25, IFT-UAM/CSIC-17-106 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The top-quark mass can be determined with very high precision from a scan of
the total $e^+e^-\to b\bar{b}W^+W^-X$ cross section near the top-pair
production threshold. We present the full calculation of electroweak and
non-resonant corrections to this process at NNLO. We discuss the size of the
new contributions and estimate the theory uncertainty on the top-quark mass in
the PS mass scheme.
| [
{
"created": "Thu, 2 Nov 2017 10:20:02 GMT",
"version": "v1"
}
] | 2017-11-03 | [
[
"Beneke",
"Martin",
""
],
[
"Maier",
"Andreas",
""
],
[
"Rauh",
"Thomas",
""
],
[
"Ruiz-Femenía",
"Pedro",
""
]
] | The top-quark mass can be determined with very high precision from a scan of the total $e^+e^-\to b\bar{b}W^+W^-X$ cross section near the top-pair production threshold. We present the full calculation of electroweak and non-resonant corrections to this process at NNLO. We discuss the size of the new contributions and estimate the theory uncertainty on the top-quark mass in the PS mass scheme. |
0704.1247 | Santi Peris | P. Masjuan and S. Peris | A Rational Approach to Resonance Saturation in large-Nc QCD | 23 pages, 2 figures | JHEP 0705:040,2007 | 10.1088/1126-6708/2007/05/040 | null | hep-ph hep-lat hep-th nucl-th | null | We point out that resonance saturation in QCD can be understood in the
large-Nc limit from the mathematical theory of Pade Approximants to meromorphic
functions. These approximants are rational functions which encompass any
saturation with a finite number of resonances as a particular example,
explaining several results which have appeared in the literature. We review the
main properties of Pade Approximants with the help of a toy model for the
<VV-AA> two-point correlator, paying particular attention to the relationship
among the Chiral Expansion, the Operator Product Expansion and the resonance
spectrum. In passing, we also comment on an old proposal made by Migdal in 1977
which has recently attracted much attention in the context of AdS/QCD models.
Finally, we apply the simplest Pade Approximant to the <VV-AA> correlator in
the real case of QCD. The general conclusion is that a rational approximant may
reliably describe a Green's function in the Euclidean, but the same is not true
in the Minkowski regime due to the appearance of unphysical poles and/or
residues.
| [
{
"created": "Tue, 10 Apr 2007 14:27:41 GMT",
"version": "v1"
}
] | 2009-11-13 | [
[
"Masjuan",
"P.",
""
],
[
"Peris",
"S.",
""
]
] | We point out that resonance saturation in QCD can be understood in the large-Nc limit from the mathematical theory of Pade Approximants to meromorphic functions. These approximants are rational functions which encompass any saturation with a finite number of resonances as a particular example, explaining several results which have appeared in the literature. We review the main properties of Pade Approximants with the help of a toy model for the <VV-AA> two-point correlator, paying particular attention to the relationship among the Chiral Expansion, the Operator Product Expansion and the resonance spectrum. In passing, we also comment on an old proposal made by Migdal in 1977 which has recently attracted much attention in the context of AdS/QCD models. Finally, we apply the simplest Pade Approximant to the <VV-AA> correlator in the real case of QCD. The general conclusion is that a rational approximant may reliably describe a Green's function in the Euclidean, but the same is not true in the Minkowski regime due to the appearance of unphysical poles and/or residues. |
hep-ph/0607101 | Nestor Armesto | J. Dias de Deus and C. Pajares | Percolation of color sources and critical temperature | LaTeX, 9 pages | Phys.Lett.B642:455-458,2006 | 10.1016/j.physletb.2006.10.018 | null | hep-ph | null | We argue that clustering of color sources, leading to the percolation
transition, may be the way to achieve deconfinement in heavy ion collisions.
The critical density for percolation is related to the effective critical
temperature of the thermal bath asociated to the presence of strong color
fields inside the percolating cluster. We find that the temperature is
rapidity, centrality and energy dependent. We emphasize the similarities of
percolation of strings with color glass condensate.
| [
{
"created": "Mon, 10 Jul 2006 09:58:09 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"de Deus",
"J. Dias",
""
],
[
"Pajares",
"C.",
""
]
] | We argue that clustering of color sources, leading to the percolation transition, may be the way to achieve deconfinement in heavy ion collisions. The critical density for percolation is related to the effective critical temperature of the thermal bath asociated to the presence of strong color fields inside the percolating cluster. We find that the temperature is rapidity, centrality and energy dependent. We emphasize the similarities of percolation of strings with color glass condensate. |
2312.12519 | Giovanni Stagnitto | Leonardo Bonino, Matteo Cacciari, Giovanni Stagnitto | Heavy Quark Fragmentation in $e^+e^-$ Collisions to NNLO+NNLL Accuracy
in Perturbative QCD | 43 pages, 15 figures, 2 tables; v2 matches the published version | JHEP 06 (2024) 040 | 10.1007/JHEP06(2024)040 | ZU-TH 79/23 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Fragmentation of heavy quarks into heavy-flavoured hadrons receives both
perturbative and non-perturbative contributions. We consider perturbative QCD
corrections to heavy quark production in $e^+e^-$ collisions to
next-to-next-to-leading order accuracy in QCD with
next-to-next-to-leading-logarithmic resummation of quasi-collinear and soft
emissions. We study multiple matching schemes, and multiple regularisations of
the soft resummation, and observe a significant dependence of the perturbative
results on these ingredients, suggesting that NNLO+NNLL perturbative accuracy
may not lead to real gains unless the interface with non-perturbative physics
is properly analysed. We confirm previous evidence that $D^{*+}$ experimental
data from CLEO/BELLE and from LEP are not reconcilable with perturbative
predictions employing standard DGLAP evolution. We extract non-perturbative
contributions from $e^+e^-$ experimental data for both $D$ and $B$ meson
fragmentation. Such contributions can be used to predict heavy-quark
fragmentation in other processes, e.g. DIS and proton-proton collisions.
| [
{
"created": "Tue, 19 Dec 2023 19:00:05 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Jun 2024 08:34:12 GMT",
"version": "v2"
}
] | 2024-06-12 | [
[
"Bonino",
"Leonardo",
""
],
[
"Cacciari",
"Matteo",
""
],
[
"Stagnitto",
"Giovanni",
""
]
] | Fragmentation of heavy quarks into heavy-flavoured hadrons receives both perturbative and non-perturbative contributions. We consider perturbative QCD corrections to heavy quark production in $e^+e^-$ collisions to next-to-next-to-leading order accuracy in QCD with next-to-next-to-leading-logarithmic resummation of quasi-collinear and soft emissions. We study multiple matching schemes, and multiple regularisations of the soft resummation, and observe a significant dependence of the perturbative results on these ingredients, suggesting that NNLO+NNLL perturbative accuracy may not lead to real gains unless the interface with non-perturbative physics is properly analysed. We confirm previous evidence that $D^{*+}$ experimental data from CLEO/BELLE and from LEP are not reconcilable with perturbative predictions employing standard DGLAP evolution. We extract non-perturbative contributions from $e^+e^-$ experimental data for both $D$ and $B$ meson fragmentation. Such contributions can be used to predict heavy-quark fragmentation in other processes, e.g. DIS and proton-proton collisions. |
hep-ph/0012192 | Sandro Ambrosanio | S.Ambrosanio (1), B.Mele (2,3), A.Nisati (2,3), S.Petrarca (3,2),
G.Polesello (4), A.Rimoldi (4,1), G.Salvini (3,2) ((1) CERN, (2) INFN Roma,
(3) U.Roma "La Sapienza", (4) INFN Pavia) | SUSY Long-Lived Massive Particles: Detection and Physics at the LHC | 11 pages, LaTeX, 4 figs (5 eps files) | null | null | CERN-TH/2000-349 | hep-ph hep-ex | null | We draw a possible scenario for the observation of massive long-lived charged
particles at the LHC detector ATLAS. The required flexibility of the detector
triggers and of the identification and reconstruction systems are discussed. As
an example, we focus on the measurement of the mass and lifetime of long-lived
charged sleptons predicted in the framework of supersymmetric models with
gauge-mediated supersymmetry (SUSY) breaking. In this case, the
next-to-lightest SUSY particle can be the light scalar partner of the tau
lepton, possibly decaying slowly into a gravitino. A wide region of the SUSY
parameters space was explored. The accessible range and precision on the
measurement of the SUSY breaking scale parameter sqrt(F) achievable with a
counting method are assessed.
| [
{
"created": "Fri, 15 Dec 2000 15:37:30 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Ambrosanio",
"S.",
""
],
[
"Mele",
"B.",
""
],
[
"Nisati",
"A.",
""
],
[
"Petrarca",
"S.",
""
],
[
"Polesello",
"G.",
""
],
[
"Rimoldi",
"A.",
""
],
[
"Salvini",
"G.",
""
]
] | We draw a possible scenario for the observation of massive long-lived charged particles at the LHC detector ATLAS. The required flexibility of the detector triggers and of the identification and reconstruction systems are discussed. As an example, we focus on the measurement of the mass and lifetime of long-lived charged sleptons predicted in the framework of supersymmetric models with gauge-mediated supersymmetry (SUSY) breaking. In this case, the next-to-lightest SUSY particle can be the light scalar partner of the tau lepton, possibly decaying slowly into a gravitino. A wide region of the SUSY parameters space was explored. The accessible range and precision on the measurement of the SUSY breaking scale parameter sqrt(F) achievable with a counting method are assessed. |
0712.2666 | Andreas Krassnigg | G. Eichmann, A. Krassnigg, M. Schwinzerl, and R. Alkofer | A covariant view on the nucleons' quark core | 62 pages, 23 figures | Annals Phys.323:2505-2553,2008 | 10.1016/j.aop.2008.02.007 | null | hep-ph hep-ex hep-lat nucl-th | null | Established results for the quark propagator in Landau gauge QCD, together
with a detailed comparison to lattice data, are used to formulate a Poincare
covariant Faddeev approach to the nucleon. The resultant three-quark amplitudes
describe the quark core of the nucleon. The nucleon's mass and its
electromagnetic form factors are calculated as functions of the current quark
mass. The corresponding results together with charge radii and magnetic moments
are discussed in connection with the contributions from various ingredients in
a consistent calculation of nucleon properties, as well as the role of the pion
cloud in such an approach.
| [
{
"created": "Mon, 17 Dec 2007 16:56:02 GMT",
"version": "v1"
}
] | 2009-12-15 | [
[
"Eichmann",
"G.",
""
],
[
"Krassnigg",
"A.",
""
],
[
"Schwinzerl",
"M.",
""
],
[
"Alkofer",
"R.",
""
]
] | Established results for the quark propagator in Landau gauge QCD, together with a detailed comparison to lattice data, are used to formulate a Poincare covariant Faddeev approach to the nucleon. The resultant three-quark amplitudes describe the quark core of the nucleon. The nucleon's mass and its electromagnetic form factors are calculated as functions of the current quark mass. The corresponding results together with charge radii and magnetic moments are discussed in connection with the contributions from various ingredients in a consistent calculation of nucleon properties, as well as the role of the pion cloud in such an approach. |
hep-ph/9911394 | Ralph Engel | Ralph Engel, T.K. Gaisser and Todor Stanev (Bartol Research Inst.) | Pion production in proton collisions with light nuclei: implications for
atmospheric neutrinos | latex, 13 pages, 6 figures | Phys.Lett.B472:113-118,2000 | 10.1016/S0370-2693(99)01418-5 | BA-99-73 | hep-ph | null | Differences among calculations of the atmospheric neutrino beam can be traced
in large part to differences in the representation of pion production by
protons interacting with nuclei in the atmosphere. In this paper we review the
existing data with the goal of determining the regions of phase space in which
new measurements could help to improve the input to the calculations.
| [
{
"created": "Wed, 17 Nov 1999 19:20:40 GMT",
"version": "v1"
}
] | 2011-05-12 | [
[
"Engel",
"Ralph",
"",
"Bartol Research Inst."
],
[
"Gaisser",
"T. K.",
"",
"Bartol Research Inst."
],
[
"Stanev",
"Todor",
"",
"Bartol Research Inst."
]
] | Differences among calculations of the atmospheric neutrino beam can be traced in large part to differences in the representation of pion production by protons interacting with nuclei in the atmosphere. In this paper we review the existing data with the goal of determining the regions of phase space in which new measurements could help to improve the input to the calculations. |
1101.0670 | Kang Young Lee | Sanghyeon Chang, Kang Young Lee, Jeonghyeon Song | The second Kaluza-Klein neutral Higgs bosons in the minimal Universal
Extra Dimension model | 22 pages, 7 figures | Phys. Lett. B 708 (2012) 144 | 10.1016/j.physletb.2012.01.047 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Loop-induced decay of a neutral Higgs boson into a pair of gluons or photons
has great implications for the Higgs discovery at the LHC. If the Higgs boson
is heavy with mass above $\sim 500\gev$, however, these radiative branching
ratios are very suppressed in the standard model (SM), as the new decay
channels are kinematically open. We note that these radiative decays can be
sizable for the heavy CP-odd second Kaluza-Klein (KK) mode of the Higgs boson,
$\chi^\tw$, in the minimal universal extra dimension model: highly degenerate
mass spectrum of the theory prohibits kinematically the dominant
KK-number-conserving decays into the first KK modes of the $W$, $Z$ and top
quark. We find that the CP-even decay of $h^{(2)} \to g g$ is absent at
one-loop level since $h^{(2)}$ couples with different mass eigenstates of
$t_{1,2}^\on$ while a gluon does with the same mass eigenstates. The $h^\tw$
production at the LHC is very suppressed. On the contrary, the process $ gg \to
\chi^\tw \to \gamma\gamma$ in an optimal scenario can be observed with
manageable SM backgrounds at the LHC.
| [
{
"created": "Tue, 4 Jan 2011 08:07:10 GMT",
"version": "v1"
},
{
"created": "Tue, 18 Jan 2011 06:02:57 GMT",
"version": "v2"
},
{
"created": "Fri, 10 Jun 2011 08:34:24 GMT",
"version": "v3"
}
] | 2012-03-13 | [
[
"Chang",
"Sanghyeon",
""
],
[
"Lee",
"Kang Young",
""
],
[
"Song",
"Jeonghyeon",
""
]
] | Loop-induced decay of a neutral Higgs boson into a pair of gluons or photons has great implications for the Higgs discovery at the LHC. If the Higgs boson is heavy with mass above $\sim 500\gev$, however, these radiative branching ratios are very suppressed in the standard model (SM), as the new decay channels are kinematically open. We note that these radiative decays can be sizable for the heavy CP-odd second Kaluza-Klein (KK) mode of the Higgs boson, $\chi^\tw$, in the minimal universal extra dimension model: highly degenerate mass spectrum of the theory prohibits kinematically the dominant KK-number-conserving decays into the first KK modes of the $W$, $Z$ and top quark. We find that the CP-even decay of $h^{(2)} \to g g$ is absent at one-loop level since $h^{(2)}$ couples with different mass eigenstates of $t_{1,2}^\on$ while a gluon does with the same mass eigenstates. The $h^\tw$ production at the LHC is very suppressed. On the contrary, the process $ gg \to \chi^\tw \to \gamma\gamma$ in an optimal scenario can be observed with manageable SM backgrounds at the LHC. |
1702.00348 | Elena Ginina | Helmut Eberl, Elena Ginina, Keisho Hidaka | Two-body decays of gluino at full one-loop level in the quark-flavour
violating MSSM | null | null | 10.1140/epjc/s10052-017-4754-4 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the two-body decays of the gluino at full one-loop level in the
Minimal Supersymmetric Standard Model with quark-flavour violation (QFV) in the
squark sector. The renormalization is done in the $\overline{\rm DR}$ scheme.
The gluon and photon radiations are included by adding the corresponding
three-body decay widths. We discuss the dependence of the gluino decay widths
on the QFV parameters. The main dependence stems from the $\tilde c_R - \tilde
t_R$ mixing in the decays to up-type squarks, and from the $\tilde s_R - \tilde
b_R$ mixing in the decays to down-type squarks due to the strong constraints
from B-physics on the other quark-flavour mixing parameters. The full one-loop
corrections to the gluino decay widths are mostly negative and of the order of
about -10\%. The QFV part stays small in the total width but can vary up to
-8\% for the decay width into the lightest squark. For the corresponding
branching ratio the effect is somehow washed out by at least a factor of two.
The electroweak corrections can be as large as 35\% of the SUSY QCD
corrections.
| [
{
"created": "Wed, 1 Feb 2017 16:48:38 GMT",
"version": "v1"
}
] | 2017-04-26 | [
[
"Eberl",
"Helmut",
""
],
[
"Ginina",
"Elena",
""
],
[
"Hidaka",
"Keisho",
""
]
] | We study the two-body decays of the gluino at full one-loop level in the Minimal Supersymmetric Standard Model with quark-flavour violation (QFV) in the squark sector. The renormalization is done in the $\overline{\rm DR}$ scheme. The gluon and photon radiations are included by adding the corresponding three-body decay widths. We discuss the dependence of the gluino decay widths on the QFV parameters. The main dependence stems from the $\tilde c_R - \tilde t_R$ mixing in the decays to up-type squarks, and from the $\tilde s_R - \tilde b_R$ mixing in the decays to down-type squarks due to the strong constraints from B-physics on the other quark-flavour mixing parameters. The full one-loop corrections to the gluino decay widths are mostly negative and of the order of about -10\%. The QFV part stays small in the total width but can vary up to -8\% for the decay width into the lightest squark. For the corresponding branching ratio the effect is somehow washed out by at least a factor of two. The electroweak corrections can be as large as 35\% of the SUSY QCD corrections. |
hep-ph/0407011 | Peschanski | C. Marquet, R. Peschanski, C. Royon | Saturation and forward jets at HERA | 9 pages, 4 figures, version to be published in PLB | Phys.Lett.B599:236-246,2004 | 10.1016/j.physletb.2004.08.052 | null | hep-ph | null | We analyse forward-jet production at HERA in the framework of the
Golec-Biernat and Wusthoff saturation models. We obtain a good description of
the forward jet cross sections measured by the H1 and ZEUS collaborations in
the two-hard-scale region kT ~ Q >> Lambda_QCD with two different
parametrisations with either significant or weak saturation effects. The weak
saturation parametrization gives a scale compatible with the one found for the
proton structure function F_2. We argue that Mueller-Navelet jets at the
Tevatron and the LHC could help distinguishing between both options.
| [
{
"created": "Thu, 1 Jul 2004 15:11:59 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Aug 2004 15:00:34 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Marquet",
"C.",
""
],
[
"Peschanski",
"R.",
""
],
[
"Royon",
"C.",
""
]
] | We analyse forward-jet production at HERA in the framework of the Golec-Biernat and Wusthoff saturation models. We obtain a good description of the forward jet cross sections measured by the H1 and ZEUS collaborations in the two-hard-scale region kT ~ Q >> Lambda_QCD with two different parametrisations with either significant or weak saturation effects. The weak saturation parametrization gives a scale compatible with the one found for the proton structure function F_2. We argue that Mueller-Navelet jets at the Tevatron and the LHC could help distinguishing between both options. |
2211.14230 | Bennie F. L. Ward | B.F.L. Ward (1), S. Jadach (2), W. Placzek (3), M. Skrzypek (2), S.A.
Yost (4) ((1) Baylor University, Waco, TX, USA, (2) Institute of Nuclear
Physics, Polish Academy of Sciences, Krakow, Poland, (3) Institute of Applied
Computer Science, Jagiellonian University, Krakow, Poland, (4) The Citadel,
Charleston, SC, USA) | Overview of theoretical precision of the luminosity at future
electron-positron colliders | 6 pages, 5 tables, talk presented by BFLW at ICHEP2022, Bologna,
Italy, 7/7/2022 | PoS(ICHEP2022)1214 | 10.22323/1.414.1214 | BU-HEPP-22-06 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | For both the FCC-ee and the ILC, to exploit properly the respective precision
physics program, the theoretical precision tag on the respective luminosity
will need to be improved from the analogs of the $ 0.054 \% (0.061\%)$ results
at LEP at $M_Z$, where the former (latter) LEP result has (does not have) the
pairs correction. At the FCC-ee at $M_Z$ one needs improvement to $0.01\%$, for
example. We present an overview of the roads one may take to reach the required
$0.01\%$ precision tag at the FCC-ee and of what the corresponding precision
expectations would be for the FCC-ee$_{350}$, ILC$_{500}$, ILC$_{1000}$, and
CLIC$_{3000}$ setups.
| [
{
"created": "Fri, 25 Nov 2022 16:42:43 GMT",
"version": "v1"
}
] | 2023-02-03 | [
[
"Ward",
"B. F. L.",
""
],
[
"Jadach",
"S.",
""
],
[
"Placzek",
"W.",
""
],
[
"Skrzypek",
"M.",
""
],
[
"Yost",
"S. A.",
""
]
] | For both the FCC-ee and the ILC, to exploit properly the respective precision physics program, the theoretical precision tag on the respective luminosity will need to be improved from the analogs of the $ 0.054 \% (0.061\%)$ results at LEP at $M_Z$, where the former (latter) LEP result has (does not have) the pairs correction. At the FCC-ee at $M_Z$ one needs improvement to $0.01\%$, for example. We present an overview of the roads one may take to reach the required $0.01\%$ precision tag at the FCC-ee and of what the corresponding precision expectations would be for the FCC-ee$_{350}$, ILC$_{500}$, ILC$_{1000}$, and CLIC$_{3000}$ setups. |
2305.14860 | Bogar D\'iaz | J. R. Alvarado Garc\'ia, D. Rosales Herrera, A. Fern\'andez T\'ellez,
Bogar D\'iaz, and J. E. Ram\'irez | Structure of the medium formed in heavy ion collisions | 15 pages, 8 figures | Universe 2023, 9(6), 291 | 10.3390/universe9060291 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the structure of the medium formed in heavy ion collisions
using three different models: the Color String Percolation Model (CSPM), the
Core-Shell-Color String Percolation Model (CSCSPM), and the Color Glass
Condensate (CGC) framework. We analyze the radial distribution function of the
transverse representation of color flux tubes in each model to determine the
medium's structure. Our results indicate that the CSPM behaves as an ideal gas,
while the CSCSPM exhibits a structural phase transition from a gas-like to a
liquid-like structure. Additionally, our analysis of the CGC framework suggests
that it produces systems that behave like interacting gases for AuAu central
collisions at RHIC energies and liquid-like structures for PbPb central
collisions at LHC energies.
| [
{
"created": "Wed, 24 May 2023 08:13:46 GMT",
"version": "v1"
}
] | 2023-06-28 | [
[
"García",
"J. R. Alvarado",
""
],
[
"Herrera",
"D. Rosales",
""
],
[
"Téllez",
"A. Fernández",
""
],
[
"Díaz",
"Bogar",
""
],
[
"Ramírez",
"J. E.",
""
]
] | We investigate the structure of the medium formed in heavy ion collisions using three different models: the Color String Percolation Model (CSPM), the Core-Shell-Color String Percolation Model (CSCSPM), and the Color Glass Condensate (CGC) framework. We analyze the radial distribution function of the transverse representation of color flux tubes in each model to determine the medium's structure. Our results indicate that the CSPM behaves as an ideal gas, while the CSCSPM exhibits a structural phase transition from a gas-like to a liquid-like structure. Additionally, our analysis of the CGC framework suggests that it produces systems that behave like interacting gases for AuAu central collisions at RHIC energies and liquid-like structures for PbPb central collisions at LHC energies. |
2103.12898 | Jorge David Castano-Yepes | Jorge David Casta\~no-Yepes | Effects of Intense Magnetic Fields, High Temperature and Density on
QCD-Related Phenomena | Ph.D. Thesis. 183 pages. Tittle and some typos corrected | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The effects of high-temperature, dense systems, and strong magnetic fields on
Quantum Chromodynamics related phenomena are studied in different perspectives:
in the high-temperature and densities, the QCD-phase diagram from the Linear
Sigma Model point of view is computed. In particular, the CEP location and
transition lines for chiral restoration were found. In the intense magnetic
fields and high-gluon density, the gluon fusion and gluon splitting channels
are proposed as new photon production sources to better explain the
experimental data in the so-called "photon puzzle". Finally, the thermal and
magnetic screening properties for gluons encoded into the polarization tensor
were addressed in terms of the Debye mass.
| [
{
"created": "Wed, 24 Mar 2021 00:13:55 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Jun 2021 16:44:47 GMT",
"version": "v2"
}
] | 2021-06-14 | [
[
"Castaño-Yepes",
"Jorge David",
""
]
] | The effects of high-temperature, dense systems, and strong magnetic fields on Quantum Chromodynamics related phenomena are studied in different perspectives: in the high-temperature and densities, the QCD-phase diagram from the Linear Sigma Model point of view is computed. In particular, the CEP location and transition lines for chiral restoration were found. In the intense magnetic fields and high-gluon density, the gluon fusion and gluon splitting channels are proposed as new photon production sources to better explain the experimental data in the so-called "photon puzzle". Finally, the thermal and magnetic screening properties for gluons encoded into the polarization tensor were addressed in terms of the Debye mass. |
hep-ph/0509366 | Stefano Rigolin | S. Rigolin (Universidad Autonoma de Madrid) | Physics reach of $\beta$-beams and $\nu$-factories: the problem of
degeneracies | 5 pages, 6 epsfig; NUFACT'05, 21-26 June 2005, Frascati | null | 10.1016/j.nuclphysbps.2006.02.006 | null | hep-ph | null | We discuss the physics reach of $\beta$-Beams and $\nu$-Factories from a
theoretical perspective, having as a guideline the problem of degeneracies. The
presence of degenerate solutions in the measure of the neutrino oscillation
parameters $\theta_{13}$ and $\delta$ is, in fact, the main problem that have
to be addressed in planning future neutrino oscillation experiments. If
degeneracies are not (at least partially) solved, it will be almost impossible
to perform, at any future facility, precise measurements of $\theta_{13}$
and/or $\delta$. After a pedagogical introduction on why degenerate solutions
arise and how we can get rid of them, we analyze the physics reach of current
$\beta$-beam and $\nu$-factory configurations. The physics reach of the
"standard" \BB is severely affected by degeneracies while a better result can
be obtained by higher-$\gamma$ setups. At the \NF the combination of Golden and
Silver channels can solve the eightfold degeneracy down to $\sin^2\theta_{13}
\le 10^{-3}$
| [
{
"created": "Fri, 30 Sep 2005 14:32:52 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Rigolin",
"S.",
"",
"Universidad Autonoma de Madrid"
]
] | We discuss the physics reach of $\beta$-Beams and $\nu$-Factories from a theoretical perspective, having as a guideline the problem of degeneracies. The presence of degenerate solutions in the measure of the neutrino oscillation parameters $\theta_{13}$ and $\delta$ is, in fact, the main problem that have to be addressed in planning future neutrino oscillation experiments. If degeneracies are not (at least partially) solved, it will be almost impossible to perform, at any future facility, precise measurements of $\theta_{13}$ and/or $\delta$. After a pedagogical introduction on why degenerate solutions arise and how we can get rid of them, we analyze the physics reach of current $\beta$-beam and $\nu$-factory configurations. The physics reach of the "standard" \BB is severely affected by degeneracies while a better result can be obtained by higher-$\gamma$ setups. At the \NF the combination of Golden and Silver channels can solve the eightfold degeneracy down to $\sin^2\theta_{13} \le 10^{-3}$ |
2009.08919 | Yu Jiao Zhu | Yu Jiao Zhu | Double soft current at one-loop in QCD | Typos in eq.(3.6), eq.(4.8) and eq.(4.9) are corrected | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the soft behavior of QCD amplitudes with multiple hard legs and
present a compact expression for double soft gluons and double soft quarks at
one-loop. The color correlation of the current basically shows a dipole
structure which couples to two hard legs at one time, except for a simple
abelian contribution which factorizes as products of one-loop and tree-level
single soft current which couples up to three hard legs. The kinematic
dependence can be expressed in terms of polylogarithms (at least up to finite
terms in $\epsilon$) and the results were displayed with time-like kinematics.
Analytical continuation to other kinematic configurations is then discussed
where we found non-trivial crossing into ingoing states. The amplitude squared
is always crossing invariant, which leads to the fact that the fully
differential soft function (and the TMD soft function) is universal up to
three-loop.
| [
{
"created": "Fri, 18 Sep 2020 16:30:32 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Sep 2021 06:34:06 GMT",
"version": "v2"
},
{
"created": "Tue, 31 Jan 2023 10:18:16 GMT",
"version": "v3"
}
] | 2023-02-01 | [
[
"Zhu",
"Yu Jiao",
""
]
] | We study the soft behavior of QCD amplitudes with multiple hard legs and present a compact expression for double soft gluons and double soft quarks at one-loop. The color correlation of the current basically shows a dipole structure which couples to two hard legs at one time, except for a simple abelian contribution which factorizes as products of one-loop and tree-level single soft current which couples up to three hard legs. The kinematic dependence can be expressed in terms of polylogarithms (at least up to finite terms in $\epsilon$) and the results were displayed with time-like kinematics. Analytical continuation to other kinematic configurations is then discussed where we found non-trivial crossing into ingoing states. The amplitude squared is always crossing invariant, which leads to the fact that the fully differential soft function (and the TMD soft function) is universal up to three-loop. |
hep-ph/0211066 | Carlos Munoz | C. Munoz | Extra matter at low energy | Talk given at 1st International Conference on String Phenomenology,
Oxford, 6-11 July 2002. 6 pages, 1 figure | null | 10.1142/9789812704917_0040 | FTUAM 02/31, IFT-UAM/CSIC-02-50 | hep-ph hep-th | null | Assuming that the Standard Model arises from the $E_8\times E_8$ Heterotic
Superstring, we try to solve the discrepancy between the unification scale
predicted by this theory ($\approx g_{GUT}\times 5.27\cdot 10^{17}$ GeV) and
the value deduced from LEP experiments ($\approx 2\cdot 10^{16}$ GeV). This
will allow us to predict the presence at low energies of three generations of
supersymmetric Higgses and vector-like colour triplets.
| [
{
"created": "Tue, 5 Nov 2002 18:31:36 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Munoz",
"C.",
""
]
] | Assuming that the Standard Model arises from the $E_8\times E_8$ Heterotic Superstring, we try to solve the discrepancy between the unification scale predicted by this theory ($\approx g_{GUT}\times 5.27\cdot 10^{17}$ GeV) and the value deduced from LEP experiments ($\approx 2\cdot 10^{16}$ GeV). This will allow us to predict the presence at low energies of three generations of supersymmetric Higgses and vector-like colour triplets. |
hep-ph/0509364 | Nicolas Borghini | Nicolas Borghini and Urs Achim Wiedemann | Multiplicity distributions for jet parton showers in a medium | 4 pages, 2 eps-figures. Talk given at Quark Matter 2005, Budapest,
4-9 Aug 2005 | Nucl. Phys. A 774 (2006) 549-552 | 10.1016/j.nuclphysa.2006.06.084 | CERN-PH-TH/2005-182 | hep-ph | null | The "jet-quenching" interpretation of suppressed high-pT hadron production at
RHIC implies that jet multiplicity distributions and jet-like particle
correlations in heavy-ion collisions at RHIC and LHC differ strongly from those
seen at e+e- or pp colliders. Here, we present an approach for describing the
changes induced by the medium, which implements jet quenching as a
probabilistic medium-modified parton shower, treating leading and subleading
parton splittings on an equal footing. We show that the strong suppression of
single inclusive hadron spectra measured in Au-Au collisions at RHIC implies a
characteristic distortion of the single inclusive distribution of soft partons
inside the jet. We determine, as a function of jet energy, to what extent the
soft jet fragments can be measured above some momentum cut.
| [
{
"created": "Fri, 30 Sep 2005 13:53:14 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Borghini",
"Nicolas",
""
],
[
"Wiedemann",
"Urs Achim",
""
]
] | The "jet-quenching" interpretation of suppressed high-pT hadron production at RHIC implies that jet multiplicity distributions and jet-like particle correlations in heavy-ion collisions at RHIC and LHC differ strongly from those seen at e+e- or pp colliders. Here, we present an approach for describing the changes induced by the medium, which implements jet quenching as a probabilistic medium-modified parton shower, treating leading and subleading parton splittings on an equal footing. We show that the strong suppression of single inclusive hadron spectra measured in Au-Au collisions at RHIC implies a characteristic distortion of the single inclusive distribution of soft partons inside the jet. We determine, as a function of jet energy, to what extent the soft jet fragments can be measured above some momentum cut. |
hep-ph/0405259 | Terunuma Sachiko | Masako Bando, Taichiro Kugo, Akio Sugamoto, Sachiko Terunuma | Pentaquark Baryons in String Theory | 38 pages, 7 figures, LaTex;to be published in Prog. Theor. Phys.
Vol.112, No.2, August(2004);in ver2 references are added and Eq.(123) is
modified;in ver3 references are added and English is improved | Prog.Theor.Phys. 112 (2004) 325-355 | 10.1143/PTP.112.325 | OCHA-PP228, YITP-04-28 | hep-ph hep-th nucl-ex nucl-th | null | The recently observed pentaquark baryons $\Theta^{+}$ and $\Xi^{--}$ are
studied in the dual gravity theory of QCD.
By developing a general formulation useful for studying the branched string
web in a curved space, simple mass formulae of the pentaquark baryons are
derived in the Maldacena prototype model for supersymmetric QCD and a more
realistic model for ordinary QCD. Even though the approximations adopted here
in deriving these formulae are extremely naive, the predicted values of the
masses do not differ significantly from their experimental values. We thus
conclude that this approach is promising for the purpose of obtaining a
description of the observed masses of pentaquarks and of their extremely narrow
decay widths. With the aim of constructing more reliable mass formulae, a
preliminary sketch is given of how spin, the hyperfine interaction and parity
are considered in the string picture.
| [
{
"created": "Wed, 26 May 2004 08:01:19 GMT",
"version": "v1"
},
{
"created": "Fri, 2 Jul 2004 10:57:35 GMT",
"version": "v2"
},
{
"created": "Sat, 24 Jul 2004 10:33:28 GMT",
"version": "v3"
}
] | 2016-09-06 | [
[
"Bando",
"Masako",
""
],
[
"Kugo",
"Taichiro",
""
],
[
"Sugamoto",
"Akio",
""
],
[
"Terunuma",
"Sachiko",
""
]
] | The recently observed pentaquark baryons $\Theta^{+}$ and $\Xi^{--}$ are studied in the dual gravity theory of QCD. By developing a general formulation useful for studying the branched string web in a curved space, simple mass formulae of the pentaquark baryons are derived in the Maldacena prototype model for supersymmetric QCD and a more realistic model for ordinary QCD. Even though the approximations adopted here in deriving these formulae are extremely naive, the predicted values of the masses do not differ significantly from their experimental values. We thus conclude that this approach is promising for the purpose of obtaining a description of the observed masses of pentaquarks and of their extremely narrow decay widths. With the aim of constructing more reliable mass formulae, a preliminary sketch is given of how spin, the hyperfine interaction and parity are considered in the string picture. |
1301.1681 | Martin Jung | Martin Jung | A robust limit for the electric dipole moment of the electron | 8 pages, 2 tables, 4 figures. v2: Extended discussion of the EDM of
Tl, corrected value for the nuclear magnetic moment of Hg (implying small
shifts in the obtained numerical values) and further minor changes | null | 10.1007/JHEP05(2013)168 | DO-TH 12/43 | hep-ph physics.atom-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Electric dipole moments constitute a competitive method to search for new
physics, being particularly sensitive to new CP-violating phases. Given the
experimental and theoretical progress in this field and more generally in
particle physics, the necessity for more reliable bounds than the ones usually
employed emerges. We therefore propose an improved extraction of the electric
dipole moment of the electron and the relevant coefficient of the
electron-nucleon coupling, taking into account theoretical uncertainties and
possible cancellations, to be used in model-dependent analyses. Specifically,
we obtain at 95% C.L. |d_e|<=0.14 10^{-26}e cm with present data, which is very
similar to the bound typically quoted from the YbF molecule, but obtained in a
more conservative manner. We examine furthermore in detail the prospects for
improvements and derive upper limits for the dipole moments of several
paramagnetic systems presently under investigation, i.e. Cesium, Rubidium and
Francium.
| [
{
"created": "Tue, 8 Jan 2013 21:00:02 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Jan 2013 19:01:46 GMT",
"version": "v2"
}
] | 2015-06-12 | [
[
"Jung",
"Martin",
""
]
] | Electric dipole moments constitute a competitive method to search for new physics, being particularly sensitive to new CP-violating phases. Given the experimental and theoretical progress in this field and more generally in particle physics, the necessity for more reliable bounds than the ones usually employed emerges. We therefore propose an improved extraction of the electric dipole moment of the electron and the relevant coefficient of the electron-nucleon coupling, taking into account theoretical uncertainties and possible cancellations, to be used in model-dependent analyses. Specifically, we obtain at 95% C.L. |d_e|<=0.14 10^{-26}e cm with present data, which is very similar to the bound typically quoted from the YbF molecule, but obtained in a more conservative manner. We examine furthermore in detail the prospects for improvements and derive upper limits for the dipole moments of several paramagnetic systems presently under investigation, i.e. Cesium, Rubidium and Francium. |
hep-ph/9905321 | Arthur Hebecker | W. Buchmuller, T. Gehrmann and A. Hebecker | Combined analysis of diffractive and inclusive structure functions in
the semiclassical framework | 3 pages LaTeX, 3 figures, talk presented at the 7th International
Workshop on Deep Inelastic Scattering and QCD (DIS99), Zeuthen, Germany,
April 19-23, 1999 | Nucl.Phys.Proc.Suppl.79:263-265,1999 | 10.1016/S0920-5632(99)00693-3 | null | hep-ph | null | Small-x DIS is described as the scattering of a partonic fluctuation of the
photon off a superposition of target color fields. Diffraction occurs if the
emerging partonic state is in a color singlet. Introducing a specific model for
the averaging over all relevant color field configurations, both diffractive
and inclusive parton distributions at some low scale Q_0^2 can be calculated. A
conventional DGLAP analysis results in a good description of diffractive and
inclusive structure functions at higher values of Q^2.
| [
{
"created": "Wed, 12 May 1999 15:34:57 GMT",
"version": "v1"
}
] | 2010-03-25 | [
[
"Buchmuller",
"W.",
""
],
[
"Gehrmann",
"T.",
""
],
[
"Hebecker",
"A.",
""
]
] | Small-x DIS is described as the scattering of a partonic fluctuation of the photon off a superposition of target color fields. Diffraction occurs if the emerging partonic state is in a color singlet. Introducing a specific model for the averaging over all relevant color field configurations, both diffractive and inclusive parton distributions at some low scale Q_0^2 can be calculated. A conventional DGLAP analysis results in a good description of diffractive and inclusive structure functions at higher values of Q^2. |
2405.03396 | Prisco Lo Chiatto | Prisco Lo Chiatto, Felix Yu | Consistent Electroweak Phenomenology of a Nearly Degenerate $Z'$ Boson | 25 pages, 5 figures | null | null | MITP-23-057 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Extracting constraints on kinetic mixing between a new $U(1)'$ gauge boson
hiding under the Standard Model $Z$ boson resonance requires the formalism of
non-Hermitian two-point correlation functions at 1-loop order. We derive
self-consistent collider constraints on $Z'$ bosons with kinetic mixing in a
narrow mass window around the $Z$ boson, considering both model-independent and
model-dependent bounds. Our treatment elucidates the importance of both avoided
level crossing and width suppression due to the quantum Zeno effect in
interpreting the existing constraints. We also discuss the implications for
future measurements on the $Z$-pole.
| [
{
"created": "Mon, 6 May 2024 12:04:12 GMT",
"version": "v1"
}
] | 2024-05-07 | [
[
"Chiatto",
"Prisco Lo",
""
],
[
"Yu",
"Felix",
""
]
] | Extracting constraints on kinetic mixing between a new $U(1)'$ gauge boson hiding under the Standard Model $Z$ boson resonance requires the formalism of non-Hermitian two-point correlation functions at 1-loop order. We derive self-consistent collider constraints on $Z'$ bosons with kinetic mixing in a narrow mass window around the $Z$ boson, considering both model-independent and model-dependent bounds. Our treatment elucidates the importance of both avoided level crossing and width suppression due to the quantum Zeno effect in interpreting the existing constraints. We also discuss the implications for future measurements on the $Z$-pole. |
1902.08426 | Antoni Szczurek | Izabela Babiarz, Wolfgang Sch\"afer and Antoni Szczurek | Associated production of $\chi_c$ pairs with a gluon in the
collinear-factorization approach | 20 pages, 14 figures, 1 table, two references were added | Phys. Rev. D 99, 074014 (2019) | 10.1103/PhysRevD.99.074014 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate cross section for production of $\chi_c$ pairs in proton-proton
collisions. The cross section for the $g g \to \chi_{c J_1} \chi_{c J_2}$ is
considerably smaller (especially for $\chi_{c 1} \chi_{c 1}$ final state) than
that obtained recently in the $k_T$-factorization approach. We calculate
therefore next-to-leading order contributions with $\chi_c$ pair and one extra
associated (mini-)jet. We find these contributions to be much larger than those
for the $2 \to 2$ contribution. Especially the emission of a leading gluon
(carrying a large momentum fraction of one of the incoming gluons) are
important. These emissions in the $k_T$-factorization approach are absorbed
into the initial state unintegrated gluon distributions. A smaller contribution
to the cross section comes from the production of central gluons emitted with
rapidities between the $\chi_c$-mesons. They do lead, however, to an
enhancement of the $\chi_c$-pair production at large rapidity distance between
the mesons. Our present study explains the size of the cross section for the
$\chi_c$ pair production obtained previously in the $k_T$-factorization
approach. Several differential distributions are presented.
| [
{
"created": "Fri, 22 Feb 2019 10:31:17 GMT",
"version": "v1"
},
{
"created": "Tue, 5 Mar 2019 13:24:21 GMT",
"version": "v2"
},
{
"created": "Thu, 7 Mar 2019 10:18:03 GMT",
"version": "v3"
}
] | 2019-04-17 | [
[
"Babiarz",
"Izabela",
""
],
[
"Schäfer",
"Wolfgang",
""
],
[
"Szczurek",
"Antoni",
""
]
] | We calculate cross section for production of $\chi_c$ pairs in proton-proton collisions. The cross section for the $g g \to \chi_{c J_1} \chi_{c J_2}$ is considerably smaller (especially for $\chi_{c 1} \chi_{c 1}$ final state) than that obtained recently in the $k_T$-factorization approach. We calculate therefore next-to-leading order contributions with $\chi_c$ pair and one extra associated (mini-)jet. We find these contributions to be much larger than those for the $2 \to 2$ contribution. Especially the emission of a leading gluon (carrying a large momentum fraction of one of the incoming gluons) are important. These emissions in the $k_T$-factorization approach are absorbed into the initial state unintegrated gluon distributions. A smaller contribution to the cross section comes from the production of central gluons emitted with rapidities between the $\chi_c$-mesons. They do lead, however, to an enhancement of the $\chi_c$-pair production at large rapidity distance between the mesons. Our present study explains the size of the cross section for the $\chi_c$ pair production obtained previously in the $k_T$-factorization approach. Several differential distributions are presented. |
1907.12444 | Amir N. Khan | Amir N. Khan, Werner Rodejohann | New physics from COHERENT data with improved Quenching Factor | 12 pages, 8 figures, Energy dependence of the QF included, Modified
to the published version | Phys. Rev. D 100, 113003 (2019) | 10.1103/PhysRevD.100.113003 | null | hep-ph astro-ph.HE hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A recent new measurement and re-analysis of past measurements suggested an
improved quenching factor value and uncertainty for CsI[Na]. This implies a
measurement of the COHERENT experiment of coherent elastic neutrino-nucleus
scattering that is closer to the Standard Model prediction and has less
uncertainty. We illustrate the impact of this improvement by revisiting fits to
the Weinberg angle, neutrino magnetic moments, neutron rms and neutrino charge
radii, neutrino non-standard interactions (in particular those relevant for
LMA-Dark) and new scalar as well as vector bosons. Significant improvement is
observed, particularly for those scenarios coherently affecting the electroweak
SM process.
| [
{
"created": "Mon, 29 Jul 2019 14:06:29 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Dec 2019 23:25:34 GMT",
"version": "v2"
}
] | 2019-12-18 | [
[
"Khan",
"Amir N.",
""
],
[
"Rodejohann",
"Werner",
""
]
] | A recent new measurement and re-analysis of past measurements suggested an improved quenching factor value and uncertainty for CsI[Na]. This implies a measurement of the COHERENT experiment of coherent elastic neutrino-nucleus scattering that is closer to the Standard Model prediction and has less uncertainty. We illustrate the impact of this improvement by revisiting fits to the Weinberg angle, neutrino magnetic moments, neutron rms and neutrino charge radii, neutrino non-standard interactions (in particular those relevant for LMA-Dark) and new scalar as well as vector bosons. Significant improvement is observed, particularly for those scenarios coherently affecting the electroweak SM process. |
1409.7392 | Mikhail Solon | Martin Bauer, Timothy Cohen, Richard J. Hill, and Mikhail P. Solon | Soft Collinear Effective Theory for Heavy WIMP Annihilation | 49 pages, 12 figures. v2: minor changes, typos fixed | null | 10.1007/JHEP01(2015)099 | EFI 14-32, FERMILAB-PUB-14-359-PPD, SLAC-PUB-16094 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a large class of models for Weakly Interacting Massive Particles (WIMPs),
the WIMP mass $M$ lies far above the weak scale $m_W$. This work identifies
universal Sudakov-type logarithms $\sim \alpha \log^2 (2\,M/m_W)$ that spoil
the naive convergence of perturbation theory for annihilation processes. An
effective field theory (EFT) framework is presented, allowing the systematic
resummation of these logarithms. Another impact of the large separation of
scales is that a long-distance wave-function distortion from electroweak boson
exchange leads to observable modifications of the cross section. Careful
accounting of momentum regions in the EFT allows the rigorously disentanglement
of this so-called Sommerfeld enhancement from the short distance hard
annihilation process. The WIMP is modeled as a heavy-particle field, while the
light, energetic, final-state electroweak gauge bosons are treated as soft and
collinear fields. Hard matching coefficients are computed at renormalization
scale $\mu \sim 2\,M$, then evolved down to $\mu \sim m_W$, where electroweak
symmetry breaking is incorporated and the matching onto the relevant quantum
mechanical Hamiltonian is performed. The example of an $SU(2)_W$ triplet scalar
dark matter candidate annihilating to line photons is used for concreteness,
allowing the numerical exploration of the impact of next-to-leading order
corrections and log resummation. For $M \simeq 3$ TeV, the resummed Sommerfeld
enhanced cross section is reduced by a factor of $\sim 3$ with respect to the
tree-level fixed order result.
| [
{
"created": "Thu, 25 Sep 2014 20:00:04 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Nov 2014 05:26:45 GMT",
"version": "v2"
}
] | 2015-06-23 | [
[
"Bauer",
"Martin",
""
],
[
"Cohen",
"Timothy",
""
],
[
"Hill",
"Richard J.",
""
],
[
"Solon",
"Mikhail P.",
""
]
] | In a large class of models for Weakly Interacting Massive Particles (WIMPs), the WIMP mass $M$ lies far above the weak scale $m_W$. This work identifies universal Sudakov-type logarithms $\sim \alpha \log^2 (2\,M/m_W)$ that spoil the naive convergence of perturbation theory for annihilation processes. An effective field theory (EFT) framework is presented, allowing the systematic resummation of these logarithms. Another impact of the large separation of scales is that a long-distance wave-function distortion from electroweak boson exchange leads to observable modifications of the cross section. Careful accounting of momentum regions in the EFT allows the rigorously disentanglement of this so-called Sommerfeld enhancement from the short distance hard annihilation process. The WIMP is modeled as a heavy-particle field, while the light, energetic, final-state electroweak gauge bosons are treated as soft and collinear fields. Hard matching coefficients are computed at renormalization scale $\mu \sim 2\,M$, then evolved down to $\mu \sim m_W$, where electroweak symmetry breaking is incorporated and the matching onto the relevant quantum mechanical Hamiltonian is performed. The example of an $SU(2)_W$ triplet scalar dark matter candidate annihilating to line photons is used for concreteness, allowing the numerical exploration of the impact of next-to-leading order corrections and log resummation. For $M \simeq 3$ TeV, the resummed Sommerfeld enhanced cross section is reduced by a factor of $\sim 3$ with respect to the tree-level fixed order result. |
2404.11952 | Mamutjan Ababekri | Mamutjan Ababekri, Jun-Lin Zhou, Ren-Tong Guo, Yong-Zheng Ren, Yu-Han
Kou, Qian Zhao, Zhong-Peng Li, Jian-Xing Li | Generation of Ultrarelativistic Vortex Leptons with Large Orbital
Angular Momenta | 5 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Ultrarelativistic vortex leptons with intrinsic orbital angular momenta (OAM)
have important applications in high energy particle physics, nuclear physics,
astrophysics, etc. However, unfortunately, their generation still poses a great
challenge. Here, we put forward a novel method for generating ultrarelativistic
vortex positrons and electrons through nonlinear Breit-Wheeler (NBW) scattering
of vortex $\gamma$ photons. For the first time, a complete angular
momentum-resolved scattering theory has been formulated, introducing the
angular momentum of laser photons and vortex particles into the conventional
NBW scattering framework. We find that vortex positron (electron) can be
produced when the outgoing electron (positron) is generated along the collision
axis. By unveiling the angular momentum transfer mechanism, we clarify that OAM
of the $\gamma$ photon and angular momenta of multiple laser photons are
entirely transferred to the generated pairs, leading to the production of
ultrarelativistic vortex positrons or electrons with large OAM. Furthermore, we
find that the cone opening angle and superposition state of the vortex $\gamma$
photon, distinct characteristics aside from its intrinsic OAM, can be
determined via the angular distribution of created pairs in NBW processes. Our
method paves the way for investigating strong-field quantum electrodynamics
processes concerning the generation and detection of vortex particle beams in
intense lasers.
| [
{
"created": "Thu, 18 Apr 2024 07:13:30 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Apr 2024 10:50:40 GMT",
"version": "v2"
}
] | 2024-04-25 | [
[
"Ababekri",
"Mamutjan",
""
],
[
"Zhou",
"Jun-Lin",
""
],
[
"Guo",
"Ren-Tong",
""
],
[
"Ren",
"Yong-Zheng",
""
],
[
"Kou",
"Yu-Han",
""
],
[
"Zhao",
"Qian",
""
],
[
"Li",
"Zhong-Peng",
""
],
[
"Li",
"Jian-Xing",
""
]
] | Ultrarelativistic vortex leptons with intrinsic orbital angular momenta (OAM) have important applications in high energy particle physics, nuclear physics, astrophysics, etc. However, unfortunately, their generation still poses a great challenge. Here, we put forward a novel method for generating ultrarelativistic vortex positrons and electrons through nonlinear Breit-Wheeler (NBW) scattering of vortex $\gamma$ photons. For the first time, a complete angular momentum-resolved scattering theory has been formulated, introducing the angular momentum of laser photons and vortex particles into the conventional NBW scattering framework. We find that vortex positron (electron) can be produced when the outgoing electron (positron) is generated along the collision axis. By unveiling the angular momentum transfer mechanism, we clarify that OAM of the $\gamma$ photon and angular momenta of multiple laser photons are entirely transferred to the generated pairs, leading to the production of ultrarelativistic vortex positrons or electrons with large OAM. Furthermore, we find that the cone opening angle and superposition state of the vortex $\gamma$ photon, distinct characteristics aside from its intrinsic OAM, can be determined via the angular distribution of created pairs in NBW processes. Our method paves the way for investigating strong-field quantum electrodynamics processes concerning the generation and detection of vortex particle beams in intense lasers. |
hep-ph/0408361 | Srubabati Goswami | Raj Gandhi, Pomita Ghoshal, Srubabati Goswami, Poonam Mehta, S. Uma
Sankar | Large Matter Effects in ${{\nu_\mu \to \nu_\tau}}$ Oscillations | Version to appear in Phys. Rev. Lett | Phys.Rev.Lett. 94 (2005) 051801 | 10.1103/PhysRevLett.94.051801 | null | hep-ph hep-ex | null | We show that matter effects change the ${\rm {\nu_\mu \to \nu_\tau}}$
oscillation probability by as much as 70% for certain ranges of energies and
pathlengths. Consequently, the ${\rm {\nu_\mu \to \nu_\mu}}$ survival
probability also undergoes large changes. A proper understanding of $\nu_\mu$
survival rates must consider matter effects in $P_{\mu \tau}$ as well as
$P_{\mu e}$. We comment on a) how these matter effects may be observed and the
sign of $\Delta_{31}$ determined in atmospheric neutrino measurements and at
neutrino factories and b) how they lead to heightened sensitivity for small
$\theta_{13}$.
| [
{
"created": "Tue, 31 Aug 2004 18:55:23 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Sep 2004 18:56:07 GMT",
"version": "v2"
},
{
"created": "Tue, 21 Dec 2004 17:36:24 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Gandhi",
"Raj",
""
],
[
"Ghoshal",
"Pomita",
""
],
[
"Goswami",
"Srubabati",
""
],
[
"Mehta",
"Poonam",
""
],
[
"Sankar",
"S. Uma",
""
]
] | We show that matter effects change the ${\rm {\nu_\mu \to \nu_\tau}}$ oscillation probability by as much as 70% for certain ranges of energies and pathlengths. Consequently, the ${\rm {\nu_\mu \to \nu_\mu}}$ survival probability also undergoes large changes. A proper understanding of $\nu_\mu$ survival rates must consider matter effects in $P_{\mu \tau}$ as well as $P_{\mu e}$. We comment on a) how these matter effects may be observed and the sign of $\Delta_{31}$ determined in atmospheric neutrino measurements and at neutrino factories and b) how they lead to heightened sensitivity for small $\theta_{13}$. |
1504.01555 | Amitava Raychaudhuri | Soumita Pramanick and Amitava Raychaudhuri (Univ. of Calcutta) | Relating small neutrino masses and mixing | Talk given by A. Raychaudhuri at the International Conference on
Massive Neutrinos, IAS, NTU, Singapore, February 2015; to appear in the
Proceedings; based closely on arXiv:1411:0320, v2: One typo fixed, v3:
Published version, minor typographical changes, references updated | IJMP A Vol 30, 1530036 (2015) | 10.1142/S0217751X15300367 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Experiments on neutrino oscillations have uncovered several small parameters,
$\theta_{13}$ being a prominent one. Others are the solar mass splitting {\em
vis-\`{a}-vis} the atmospheric one and the deviation of $\theta_{23}$ from
maximal mixing. In this talk we elaborate on a neutrino mass model based on the
see-saw mechanism in which the mixing angles to start with are either vanishing
($\theta_{13}$ and $\theta_{12}$) or $\pi/4$ ($\theta_{23}$). The atmospheric
mass splitting is taken as a part of this initial structure but the solar
splitting is absent. A perturbative contribution, originating from a Type-I
see-saw, results in non-zero values of $\theta_{13}$, $\theta_{12}$, $\Delta
m^2_{solar}$, and shifts $\theta_{23}$ slightly from $\pi/4$, interrelating
them all. The model incorporates CP-violation, the phase $\delta$ being close
to 3$\pi$/2 for (a) quasi-degeneracy or (b) inverted mass ordering. It will be
put to test as the neutrino parameters get better determined.
| [
{
"created": "Tue, 7 Apr 2015 11:29:53 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Apr 2015 11:41:47 GMT",
"version": "v2"
},
{
"created": "Tue, 26 May 2015 08:11:08 GMT",
"version": "v3"
}
] | 2015-05-27 | [
[
"Pramanick",
"Soumita",
"",
"Univ. of Calcutta"
],
[
"Raychaudhuri",
"Amitava",
"",
"Univ. of Calcutta"
]
] | Experiments on neutrino oscillations have uncovered several small parameters, $\theta_{13}$ being a prominent one. Others are the solar mass splitting {\em vis-\`{a}-vis} the atmospheric one and the deviation of $\theta_{23}$ from maximal mixing. In this talk we elaborate on a neutrino mass model based on the see-saw mechanism in which the mixing angles to start with are either vanishing ($\theta_{13}$ and $\theta_{12}$) or $\pi/4$ ($\theta_{23}$). The atmospheric mass splitting is taken as a part of this initial structure but the solar splitting is absent. A perturbative contribution, originating from a Type-I see-saw, results in non-zero values of $\theta_{13}$, $\theta_{12}$, $\Delta m^2_{solar}$, and shifts $\theta_{23}$ slightly from $\pi/4$, interrelating them all. The model incorporates CP-violation, the phase $\delta$ being close to 3$\pi$/2 for (a) quasi-degeneracy or (b) inverted mass ordering. It will be put to test as the neutrino parameters get better determined. |
0705.0384 | David Blaschke | D. Blaschke, M. Buballa, A.E. Radzhabov, M.K. Volkov | Effects of mesonic correlations in the QCD phase transition | 11 pages, 4 figures; version accepted for publication in Yad. Fiz.,
text extended, 1 figure added | Yad.Fiz.71:2012-2018,2008; Phys.Atom.Nucl.71:1981-1987,2008 | 10.1134/S1063778808110161 | null | hep-ph nucl-th | null | The finite temperature phase transition of strongly interacting matter is
studied within a nonlocal chiral quark model of the NJL type coupled to a
Polyakov loop. In contrast to previous investigations which were restricted to
the mean-field approximation, mesonic correlations are included by evaluating
the quark-antiquark ring sum. For physical pion masses, we find that the pions
dominate the pressure below the phase transition, whereas above T_c the
pressure is well described by the mean-field approximation result. For large
pion masses, as realized in lattice simulations, the meson effects are
suppressed.
| [
{
"created": "Thu, 3 May 2007 19:13:39 GMT",
"version": "v1"
},
{
"created": "Fri, 11 May 2007 14:54:41 GMT",
"version": "v2"
},
{
"created": "Fri, 14 Mar 2008 11:34:49 GMT",
"version": "v3"
}
] | 2008-12-18 | [
[
"Blaschke",
"D.",
""
],
[
"Buballa",
"M.",
""
],
[
"Radzhabov",
"A. E.",
""
],
[
"Volkov",
"M. K.",
""
]
] | The finite temperature phase transition of strongly interacting matter is studied within a nonlocal chiral quark model of the NJL type coupled to a Polyakov loop. In contrast to previous investigations which were restricted to the mean-field approximation, mesonic correlations are included by evaluating the quark-antiquark ring sum. For physical pion masses, we find that the pions dominate the pressure below the phase transition, whereas above T_c the pressure is well described by the mean-field approximation result. For large pion masses, as realized in lattice simulations, the meson effects are suppressed. |
1211.3745 | Aoife Bharucha | Aoife Bharucha, Jan Kalinowski, Gudrid Moortgat-Pick, Krzysztof
Rolbiecki and Georg Weiglein | One-loop effects on MSSM parameter determination via chargino production
at the LC | 23 pages, 4 figures, v2: typos corrected, minor clarifications,
version submitted to journal | Eur. Phys. J. C (2013) 73: 2446 | 10.1140/epjc/s10052-013-2446-2 | DESY 12-207 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | At a future linear collider, very precise measurements, typically with errors
of <1%, are expected to be achievable. Such an accuracy yields sensitivity to
quantum corrections, which therefore must be incorporated into theoretical
calculations in order to determine the underlying new physics parameters from
linear collider measurements. In the context of the chargino--neutralino sector
of the minimal supersymmetric standard model, this involves fitting one-loop
predictions to prospective measurements of cross sections, forward-backward
asymmetries and the accessible chargino and neutralino masses. Taking recent
results from LHC SUSY and Higgs searches into account, we consider three
phenomenological scenarios, each displaying characteristic features. Our
analysis demonstrates how an accurate determination of the desired parameters
is possible, and could additionally provide access to the stop masses and
mixing angle.
| [
{
"created": "Thu, 15 Nov 2012 21:00:04 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Mar 2013 16:01:28 GMT",
"version": "v2"
}
] | 2013-07-22 | [
[
"Bharucha",
"Aoife",
""
],
[
"Kalinowski",
"Jan",
""
],
[
"Moortgat-Pick",
"Gudrid",
""
],
[
"Rolbiecki",
"Krzysztof",
""
],
[
"Weiglein",
"Georg",
""
]
] | At a future linear collider, very precise measurements, typically with errors of <1%, are expected to be achievable. Such an accuracy yields sensitivity to quantum corrections, which therefore must be incorporated into theoretical calculations in order to determine the underlying new physics parameters from linear collider measurements. In the context of the chargino--neutralino sector of the minimal supersymmetric standard model, this involves fitting one-loop predictions to prospective measurements of cross sections, forward-backward asymmetries and the accessible chargino and neutralino masses. Taking recent results from LHC SUSY and Higgs searches into account, we consider three phenomenological scenarios, each displaying characteristic features. Our analysis demonstrates how an accurate determination of the desired parameters is possible, and could additionally provide access to the stop masses and mixing angle. |
hep-ph/0505087 | Alexandra Gurinovich | V.G. Baryshevsky, A.A. Gurinovich | Spin rotation and oscillations for high energy particles in a crystal
and possibility to measure the quadrupole moments and tensor polarizabilities
of elementary particles and nuclei | reported at RC2005; prepared in the framework of INTAS
Project#03-52-6155 | Nucl.Instrum.Meth.B252:136-141,2006 | 10.1016/j.nimb.2006.06.015 | null | hep-ph | null | It is shown that particle motion in a bent (straight) crystal is accompanied
by particle spin rotation and oscillations that allows to measure the tensor
electric and magnetic polarizabilities of nuclei and elementary particles. It
is shown that channelling of particles in either straight or bent crystal with
the polarized nuclei could be used both to analyze polarization of high energy
particles and polarize them.
| [
{
"created": "Wed, 11 May 2005 07:19:50 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Oct 2005 10:08:07 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Baryshevsky",
"V. G.",
""
],
[
"Gurinovich",
"A. A.",
""
]
] | It is shown that particle motion in a bent (straight) crystal is accompanied by particle spin rotation and oscillations that allows to measure the tensor electric and magnetic polarizabilities of nuclei and elementary particles. It is shown that channelling of particles in either straight or bent crystal with the polarized nuclei could be used both to analyze polarization of high energy particles and polarize them. |
hep-ph/9612306 | Ramesh Anishetty | Ramesh Anishetty, N.D. Hari Dass and H.S. Sharatchandra | Implications of chiral symmetry for scalar isoscalar channel and multi-
nucleon forces | 4 pages, Revtex, 3 figures in .ps files | null | null | IMSc-96/12/31 | hep-ph nucl-th | null | Chiral perturbation theory has to be substantially modified for the problem
of nuclear forces. Loop effects dominate over tree level effects. The dominant
behaviours in the scalar isoscalar channel and multi-nucleon forces are
obtained in the chiral limit and for a small explicit breaking.
| [
{
"created": "Tue, 10 Dec 1996 06:16:30 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Anishetty",
"Ramesh",
""
],
[
"Dass",
"N. D. Hari",
""
],
[
"Sharatchandra",
"H. S.",
""
]
] | Chiral perturbation theory has to be substantially modified for the problem of nuclear forces. Loop effects dominate over tree level effects. The dominant behaviours in the scalar isoscalar channel and multi-nucleon forces are obtained in the chiral limit and for a small explicit breaking. |
hep-ph/0410124 | Dong-Pil Min | Masayasu Harada, Dong-Pil Min, Tae-Sun Park, Chihiro Sasaki and
Chaejun Song | An Effective Field Theory at Finite Density | 39 pages and 7 eps figures | null | null | SNUTP-04-019, DPNU-04-17 | hep-ph | null | An effective theory to treat the dense nuclear medium by the perturbative
expansion method is proposed as a natural extension of the Heavy Baryon Chiral
Perturbation Theory (HBChPT). Treating the Fermi momentum scale as a separate
scale of the system, we get an improved convergence and the conceptually clear
interpretation. We compute the pion decay constant and the pion velocity in the
nuclear medium, and find their characters different from what the usual HBChPT
predicts. We also obtain the Debye screening scale at the normal nuclear matter
density, and the damping scale of the pion wave. Those results indicate that
the present theory, albeit its improvement over the HBChPT, has the limitation
yet to go over to the medium of about 1.3 times of normal matter density due to
the absence of the intrinsic density dependence of the coupling constants. We
discuss how we overcome this limitation in terms of the renormalization method.
| [
{
"created": "Fri, 8 Oct 2004 06:21:59 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Harada",
"Masayasu",
""
],
[
"Min",
"Dong-Pil",
""
],
[
"Park",
"Tae-Sun",
""
],
[
"Sasaki",
"Chihiro",
""
],
[
"Song",
"Chaejun",
""
]
] | An effective theory to treat the dense nuclear medium by the perturbative expansion method is proposed as a natural extension of the Heavy Baryon Chiral Perturbation Theory (HBChPT). Treating the Fermi momentum scale as a separate scale of the system, we get an improved convergence and the conceptually clear interpretation. We compute the pion decay constant and the pion velocity in the nuclear medium, and find their characters different from what the usual HBChPT predicts. We also obtain the Debye screening scale at the normal nuclear matter density, and the damping scale of the pion wave. Those results indicate that the present theory, albeit its improvement over the HBChPT, has the limitation yet to go over to the medium of about 1.3 times of normal matter density due to the absence of the intrinsic density dependence of the coupling constants. We discuss how we overcome this limitation in terms of the renormalization method. |
1007.1641 | Pasquale Di Bari | Enrico Bertuzzo, Pasquale Di Bari, Luca Marzola | The problem of the initial conditions in flavoured leptogenesis and the
tauon N_2-dominated scenario | 36 pages, 6 figures; v2: added 2 Ref.'s, footnotes, 1 sentence in the
abstract; fixed typos and text improved; 5.6 expanded; version to appear in
Nucl. Phys. B | Nucl.Phys.B849:521-548,2011 | 10.1016/j.nuclphysb.2011.03.027 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the conditions to realize a scenario of strong thermal
leptogenesis, where the final asymmetry is fully independent of the initial
conditions, when both heavy and light flavor effects are taken into account. In
particular the contribution to the final asymmetry from a residual initial
pre-existing asymmetry has to be negligible. We show that in the case of a
hierarchical right-handed (RH) neutrino mass spectrum, the only possible way is
a N_2-dominated leptogenesis scenario with a lightest RH neutrino mass M_1 <<
10^9 GeV and with a next-to-lightest RH neutrino mass 10^12 GeV >> M_2 >> 10^9
GeV. This scenario necessarily requires the presence of a heaviest third RH
neutrino specie. Moreover, we show that the final asymmetry has to be
dominantly produced in the tauon flavour while the electron and the muon
asymmetries have to be efficiently washed out by the lightest RH neutrino
inverse processes. Intriguingly, such seemingly special conditions for
successful strong thermal leptogenesis are naturally fulfilled within
SO(10)-inspired models. Besides the tauon N_2-dominated scenario, successful
strong thermal leptogenesis is also achieved in scenarios with quasi-degenerate
RH neutrino masses. We also comment on the supersymmetric case. We also derive
an expression for the final asymmetry produced from leptogenesis taking fully
into account heavy neutrino flavour effects in the specific case $M_1\gg
10^{12}\,{\rm GeV}$ (heavy flavoured scenario), a result that can be extended
to any other mass pattern.
| [
{
"created": "Fri, 9 Jul 2010 18:28:39 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Apr 2011 09:34:07 GMT",
"version": "v2"
}
] | 2011-05-25 | [
[
"Bertuzzo",
"Enrico",
""
],
[
"Di Bari",
"Pasquale",
""
],
[
"Marzola",
"Luca",
""
]
] | We discuss the conditions to realize a scenario of strong thermal leptogenesis, where the final asymmetry is fully independent of the initial conditions, when both heavy and light flavor effects are taken into account. In particular the contribution to the final asymmetry from a residual initial pre-existing asymmetry has to be negligible. We show that in the case of a hierarchical right-handed (RH) neutrino mass spectrum, the only possible way is a N_2-dominated leptogenesis scenario with a lightest RH neutrino mass M_1 << 10^9 GeV and with a next-to-lightest RH neutrino mass 10^12 GeV >> M_2 >> 10^9 GeV. This scenario necessarily requires the presence of a heaviest third RH neutrino specie. Moreover, we show that the final asymmetry has to be dominantly produced in the tauon flavour while the electron and the muon asymmetries have to be efficiently washed out by the lightest RH neutrino inverse processes. Intriguingly, such seemingly special conditions for successful strong thermal leptogenesis are naturally fulfilled within SO(10)-inspired models. Besides the tauon N_2-dominated scenario, successful strong thermal leptogenesis is also achieved in scenarios with quasi-degenerate RH neutrino masses. We also comment on the supersymmetric case. We also derive an expression for the final asymmetry produced from leptogenesis taking fully into account heavy neutrino flavour effects in the specific case $M_1\gg 10^{12}\,{\rm GeV}$ (heavy flavoured scenario), a result that can be extended to any other mass pattern. |
1801.08401 | Alexis Kalogeropoulos | Alexis Kalogeropoulos and Johan Alwall | The SysCalc code: A tool to derive theoretical systematic uncertainties | 17 pages, 5 figures | null | null | null | hep-ph hep-ex physics.comp-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Undisputedly, derivation of theoretical systematic uncertainties is an
inseparable ingredient of any robust analysis dealing with experimental data.
However, it is not uncommon, even for those analyses that use state of the art
methods and tools to suffer from insufficient statistics when it comes to the
simulated datasets used to estimate systematic uncertainties. This practically
limits the power, and sometimes the robustness of the analysis.
In this paper, we present SysCalc, a code which is able to derive weights for
various important theoretical systematic uncertainties, including those related
to the choice of the Parton Distribution Function sets and the various scale
choices. SysCalc utilizes the central sample generated events to estimate the
related systematic uncertainties, thus, omitting the need for generating
dedicated systematics datasets, and with only a minimal added cost in terms of
computing resources. In this paper we discuss the working principles of the
code accompanied by various validation plots. We also discuss the structure of
the code followed by a practical guide for how to use the tool.
| [
{
"created": "Thu, 25 Jan 2018 14:00:19 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Jan 2018 01:21:57 GMT",
"version": "v2"
}
] | 2018-01-29 | [
[
"Kalogeropoulos",
"Alexis",
""
],
[
"Alwall",
"Johan",
""
]
] | Undisputedly, derivation of theoretical systematic uncertainties is an inseparable ingredient of any robust analysis dealing with experimental data. However, it is not uncommon, even for those analyses that use state of the art methods and tools to suffer from insufficient statistics when it comes to the simulated datasets used to estimate systematic uncertainties. This practically limits the power, and sometimes the robustness of the analysis. In this paper, we present SysCalc, a code which is able to derive weights for various important theoretical systematic uncertainties, including those related to the choice of the Parton Distribution Function sets and the various scale choices. SysCalc utilizes the central sample generated events to estimate the related systematic uncertainties, thus, omitting the need for generating dedicated systematics datasets, and with only a minimal added cost in terms of computing resources. In this paper we discuss the working principles of the code accompanied by various validation plots. We also discuss the structure of the code followed by a practical guide for how to use the tool. |
hep-ph/9701412 | Slava Ilyin | P.A. Baikov, E.E. Boos, M.N. Dubinin, V.F. Edneral, V.A. Ilyin, D.V.
Kovalenko, A.P. Kryukov, A.E. Pukhov, V.I. Savrin, A.V. Semenov, S.A.
Shichanin | Physical results by means of CompHEP | 18 pages, standard LaTeX code, uses epsf macros; 13 figures (uses 11
files in PS and EPS formats). Talk presented at the Xth Workshop on High
Energy Physics and Quantum Field Theory (20-26 September 1995, Zvenigorod,
Russia). The code of CompHEP package is available at
http://theory.npi.msu.su/~pukhov/comphep.html | null | null | Proceedings of the X Int. Workshop QFTHEP'95, ed. by B.B.Levtchenko
and V.I.Savrin, Moscow St. University, Moscow, 1996, p.101-116 | hep-ph | null | The CompHEP package was developed for calculations of decay and high energy
collision processes with, correspondingly, up to 5 and 4 final particles in the
lowest order (tree) approximation. The main idea put into CompHEP was to make
available passing from the Lagrangian to final distributions efficiently with
high level automation what is extremely needed in collider physics.
The present talk describes a general structure of the CompHEP facilities and
reports some physical results obtained with its help. The main purpose of the
talk is to attract the attention of high energy physicists to this
user-friendly package which is completely aimed at making easier their routine
and tedious calculations in the TeV region.
| [
{
"created": "Wed, 29 Jan 1997 18:54:03 GMT",
"version": "v1"
},
{
"created": "Fri, 31 Jan 1997 12:51:57 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Baikov",
"P. A.",
""
],
[
"Boos",
"E. E.",
""
],
[
"Dubinin",
"M. N.",
""
],
[
"Edneral",
"V. F.",
""
],
[
"Ilyin",
"V. A.",
""
],
[
"Kovalenko",
"D. V.",
""
],
[
"Kryukov",
"A. P.",
""
],
[
"Pukhov",
"A. E.",
""
],
[
"Savrin",
"V. I.",
""
],
[
"Semenov",
"A. V.",
""
],
[
"Shichanin",
"S. A.",
""
]
] | The CompHEP package was developed for calculations of decay and high energy collision processes with, correspondingly, up to 5 and 4 final particles in the lowest order (tree) approximation. The main idea put into CompHEP was to make available passing from the Lagrangian to final distributions efficiently with high level automation what is extremely needed in collider physics. The present talk describes a general structure of the CompHEP facilities and reports some physical results obtained with its help. The main purpose of the talk is to attract the attention of high energy physicists to this user-friendly package which is completely aimed at making easier their routine and tedious calculations in the TeV region. |
hep-ph/9205227 | null | M. Dine and D. A. MacIntire | Supersymmetry, Naturalness, and Dynamical Supersymmetry Breaking | 20pages, SCIPP 91/16 | Phys.Rev. D46 (1992) 2594-2601 | 10.1103/PhysRevD.46.2594 | null | hep-ph | null | Models with dynamical supersymmetry breaking have the potential to solve many
of the naturalness problems of hidden sector supergravity models. We review the
argument that in a generic supergravity theory in which supersymmetry is {\it
dynamically} broken in the hidden sector, only tiny Majorana masses for
gauginos are generated. This situation is similar to that of theories with
continuous R-symmetries, for which Hall and Randall have suggested that gluino
masses could arise through mixings with an octet of chiral fields. We note that
in hidden sector models, such mixing can only occur if the auxiliary D field of
a $U(1)$ gauge field has an expectation value. This in turn gives rise to a
catastrophically large Fayet-Iliopoulos term for ordinary hypercharge. To solve
this problem it is necessary to unify hypercharge at least partially in a
non-Abelian group. We consider, also, some general issues in models with
continuous or discrete R symmetries, noting that it may be necessary to include
$SU(2)$ triplet fields, and that these are subject to various constraints. In
the course of these discussions, we consider a number of naturalness problems.
We suggest that the so-called ``$\mu$-problem" is not a problem, and point out
that in models in which the axion decay constant is directly related to the
SUSY breaking scale, squarks, sleptons and Higgs particles generically acquire
huge masses.
| [
{
"created": "Wed, 20 May 1992 21:06:00 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Dine",
"M.",
""
],
[
"MacIntire",
"D. A.",
""
]
] | Models with dynamical supersymmetry breaking have the potential to solve many of the naturalness problems of hidden sector supergravity models. We review the argument that in a generic supergravity theory in which supersymmetry is {\it dynamically} broken in the hidden sector, only tiny Majorana masses for gauginos are generated. This situation is similar to that of theories with continuous R-symmetries, for which Hall and Randall have suggested that gluino masses could arise through mixings with an octet of chiral fields. We note that in hidden sector models, such mixing can only occur if the auxiliary D field of a $U(1)$ gauge field has an expectation value. This in turn gives rise to a catastrophically large Fayet-Iliopoulos term for ordinary hypercharge. To solve this problem it is necessary to unify hypercharge at least partially in a non-Abelian group. We consider, also, some general issues in models with continuous or discrete R symmetries, noting that it may be necessary to include $SU(2)$ triplet fields, and that these are subject to various constraints. In the course of these discussions, we consider a number of naturalness problems. We suggest that the so-called ``$\mu$-problem" is not a problem, and point out that in models in which the axion decay constant is directly related to the SUSY breaking scale, squarks, sleptons and Higgs particles generically acquire huge masses. |
hep-ph/0611284 | Utpal Sarkar | C.T. Hill, I. Mocioiu, E.A. Paschos and U. Sarkar | Neutrino Phenomenology, Dark Energy and Leptogenesis from
pseudo-Nambu-Goldstone Bosons | 15 pages, 2 figures | Phys.Lett.B651:188-194,2007 | 10.1016/j.physletb.2007.06.006 | null | hep-ph | null | We consider a model of dynamical neutrino masses via the see-saw mechanism.
Nambu-Goldstone bosons (majorons) arise associated with the formation of the
heavy right-handed majorana masses. These bosons then acquire naturally soft
masses (become pNGB's) at loop level via the Higgs-Yukawa mass terms. These
models, like the original neutrino pNGB quintessence schemes of the 1980's that
proceed through the Dirac masses, are natural, have cosmological implications
through mass varying neutrinos, long range forces, and provide a soft potential
for dark energy. We further argue that these models can explain leptogenesis
naturally through the decays of the right-handed neutrinos.
| [
{
"created": "Wed, 22 Nov 2006 06:25:41 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Hill",
"C. T.",
""
],
[
"Mocioiu",
"I.",
""
],
[
"Paschos",
"E. A.",
""
],
[
"Sarkar",
"U.",
""
]
] | We consider a model of dynamical neutrino masses via the see-saw mechanism. Nambu-Goldstone bosons (majorons) arise associated with the formation of the heavy right-handed majorana masses. These bosons then acquire naturally soft masses (become pNGB's) at loop level via the Higgs-Yukawa mass terms. These models, like the original neutrino pNGB quintessence schemes of the 1980's that proceed through the Dirac masses, are natural, have cosmological implications through mass varying neutrinos, long range forces, and provide a soft potential for dark energy. We further argue that these models can explain leptogenesis naturally through the decays of the right-handed neutrinos. |
hep-ph/0510035 | Konstantin Goulianos | K. Goulianos | Twenty Years of Diffraction at the Tevatron | 6 pages, Presented at EDS-2005, XIth International Conference on
Elastic and Diffractive Scattering, Chateau de Blois, France, 15-20 May 2005 | null | null | null | hep-ph | null | Results on diffractive particle interactions from the Fermilab Tevatron
pbar-p collider are placed in perspective through a QCD inspired
phenomenological approach, which exploits scaling and factorization properties
observed in data. The results discussed are those obtained by the CDF
Collaboration from a comprehensive set of single, double, and multigap soft and
hard diffraction processes studied during the twenty year period since 1985,
when the CDF diffractive program was proposed and the first Blois Workshop was
held.
| [
{
"created": "Mon, 3 Oct 2005 20:47:04 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Goulianos",
"K.",
""
]
] | Results on diffractive particle interactions from the Fermilab Tevatron pbar-p collider are placed in perspective through a QCD inspired phenomenological approach, which exploits scaling and factorization properties observed in data. The results discussed are those obtained by the CDF Collaboration from a comprehensive set of single, double, and multigap soft and hard diffraction processes studied during the twenty year period since 1985, when the CDF diffractive program was proposed and the first Blois Workshop was held. |
1411.5332 | Danning Li | Danning Li, Song He and Mei Huang | Temperature dependent transport coefficients in a dynamical holographic
QCD model | 19 pages, 8 figures, regular paper | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate temperature dependent behavior of various transport
coefficients in a dynamical holographical QCD model. We show the nontrivial
temperature dependent behavior of the transport coefficients, like bulk
viscosity, electric conductivity as well as jet quenching parameter, and it is
found that all these quantities reveal information of the phase transition.
Furthermore, with introducing higher derivative corrections in 5D gravity, the
shear viscosity over entropy density ratio also shows a valley around phase
transition, and it is found that the shear viscosity over entropy density ratio
times the jet quenching over temperature cubic ratio almost remains as a
constant above phase transition, and the value is two times larger than the
perturbative result in Phys.Rev.Lett.99.192301(2007).
| [
{
"created": "Wed, 19 Nov 2014 19:39:15 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Li",
"Danning",
""
],
[
"He",
"Song",
""
],
[
"Huang",
"Mei",
""
]
] | We investigate temperature dependent behavior of various transport coefficients in a dynamical holographical QCD model. We show the nontrivial temperature dependent behavior of the transport coefficients, like bulk viscosity, electric conductivity as well as jet quenching parameter, and it is found that all these quantities reveal information of the phase transition. Furthermore, with introducing higher derivative corrections in 5D gravity, the shear viscosity over entropy density ratio also shows a valley around phase transition, and it is found that the shear viscosity over entropy density ratio times the jet quenching over temperature cubic ratio almost remains as a constant above phase transition, and the value is two times larger than the perturbative result in Phys.Rev.Lett.99.192301(2007). |
1701.06287 | Yoshio Koide | Yoshio Koide and Hiroyuki Nishiura | Flavon VEV Scales in U(3)$\times$U(3)$'$ Model | 23 pages, 1 figure, Introduction revised, Appendix remuved | null | 10.1142/S0217751X17500853 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have already proposed a quark and lepton mass matrix model based on
U(3)$\times$U(3)$'$ family symmetry as the so-called Yukawaon model, in which
the U(3) symmetry is broken by VEVs of flavons $(\Phi_f)_i^{\ \alpha}$ which
are $({\bf 3}, {\bf 3}^*)$ of U(3)$\times$U(3)$'$. The model has successfully
provided the unified description of quark and lepton masses and mixings by
using the observed charged lepton masses as only family-number dependent input
parameters. Our next concern is scales of VEVs of the flavons. In the present
paper, we estimate the magnitudes of the VEV scales of flavons of the model
which is newly reconstructed without changing the previous phenomenological
success of parameter fitting for masses and mixings of quarks and leptons. We
estimate that VEVs of flavons with $({\bf 8+1}, {\bf 1})$, $({\bf 3}, {\bf
3}^*)$, and $({\bf 1}, {\bf 8+1})$ are of 25the orders of $10$ TeV, $10^4$ TeV,
and $10^7$ TeV, respectively.
| [
{
"created": "Mon, 23 Jan 2017 07:54:59 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Feb 2017 07:36:44 GMT",
"version": "v2"
}
] | 2017-06-28 | [
[
"Koide",
"Yoshio",
""
],
[
"Nishiura",
"Hiroyuki",
""
]
] | We have already proposed a quark and lepton mass matrix model based on U(3)$\times$U(3)$'$ family symmetry as the so-called Yukawaon model, in which the U(3) symmetry is broken by VEVs of flavons $(\Phi_f)_i^{\ \alpha}$ which are $({\bf 3}, {\bf 3}^*)$ of U(3)$\times$U(3)$'$. The model has successfully provided the unified description of quark and lepton masses and mixings by using the observed charged lepton masses as only family-number dependent input parameters. Our next concern is scales of VEVs of the flavons. In the present paper, we estimate the magnitudes of the VEV scales of flavons of the model which is newly reconstructed without changing the previous phenomenological success of parameter fitting for masses and mixings of quarks and leptons. We estimate that VEVs of flavons with $({\bf 8+1}, {\bf 1})$, $({\bf 3}, {\bf 3}^*)$, and $({\bf 1}, {\bf 8+1})$ are of 25the orders of $10$ TeV, $10^4$ TeV, and $10^7$ TeV, respectively. |
0712.0490 | Sergey Goloskokov | S.V.Goloskokov | Diffractive vector meson electroproduction at small Bjorken $x$ within
GPD approach | 6 pages, 5 figures, presented at Symmetries and Spin meeting, Prague,
8- 14 July, 2007 | Eur.Phys.J.ST162:25-30,2008 | 10.1140/epjst/e2008-00771-2 | null | hep-ph | null | We study light vector meson electroproduction at small $x$ within the
generalized parton distributions (GPDs) model. The modified perturbative
approach is used, where the quark transverse degrees of freedom in the vector
meson wave function and hard subprocess are considered. Our results on the
cross section and spin observables are in good agreement with experiment
| [
{
"created": "Tue, 4 Dec 2007 11:35:18 GMT",
"version": "v1"
}
] | 2008-12-18 | [
[
"Goloskokov",
"S. V.",
""
]
] | We study light vector meson electroproduction at small $x$ within the generalized parton distributions (GPDs) model. The modified perturbative approach is used, where the quark transverse degrees of freedom in the vector meson wave function and hard subprocess are considered. Our results on the cross section and spin observables are in good agreement with experiment |
2107.14165 | Jo\~ao Pedro Pino Gon\c{c}alves | Cesar Bonilla, A. E. C\'arcamo Hern\'andez, Jo\~ao Gon\c{c}alves,
Felipe F. Freitas, Ant\'onio P. Morais, R. Pasechnik | Collider signatures of vector-like fermions from a flavor symmetric
model | 32 pages,16 figures. Additional references and discussion. Matches
version to be published in JHEP | null | 10.1007/JHEP01(2022)154 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We propose a model with two Higgs doublets and several $SU(2)$ scalar
singlets with a global non-Abelian flavor symmetry
$\mathcal{Q}_6\times\mathcal{Z}_2$. This discrete group accounts for the
observed pattern of fermion masses and mixing angles after spontaneous symmetry
breaking. In this scenario only the third generation of fermions get their
masses as in the Standard Model (SM). The masses of the remaining fermions are
generated through a seesaw-like mechanism. To that end, the matter content of
the model is enlarged by introducing electrically charged vector-like fermions
(VLFs), right handed Majorana neutrinos and several SM scalar singlets. Here we
study the processes involving VLFs that are within the reach of the Large
Hadron Collider (LHC). We perform collider studies for vector-like leptons
(VLLs) and vector-like quarks (VLQs), focusing on double production channels
for both cases, while for VLLs single production topologies are also included.
Utilizing genetic algorithms for neural network optimization, we determine the
statistical significance for a hypothetical discovery at future LHC runs. In
particular, we show that we can not safely exclude VLLs for masses greater than
$200~\mathrm{GeV}$. For VLQ's in our model, we show that we can probe their
masses up to 3.8 TeV, if we take only into account the high-luminosity phase of
the LHC. Considering Run-III luminosities, we can also exclude VLQs for masses
up to $3.4~\mathrm{TeV}$. We also show how the model with predicted VLL masses
accommodates the muon anomalous magnetic moment.
| [
{
"created": "Thu, 29 Jul 2021 16:39:32 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Aug 2021 14:37:59 GMT",
"version": "v2"
},
{
"created": "Thu, 6 Jan 2022 10:20:49 GMT",
"version": "v3"
}
] | 2022-02-16 | [
[
"Bonilla",
"Cesar",
""
],
[
"Hernández",
"A. E. Cárcamo",
""
],
[
"Gonçalves",
"João",
""
],
[
"Freitas",
"Felipe F.",
""
],
[
"Morais",
"António P.",
""
],
[
"Pasechnik",
"R.",
""
]
] | We propose a model with two Higgs doublets and several $SU(2)$ scalar singlets with a global non-Abelian flavor symmetry $\mathcal{Q}_6\times\mathcal{Z}_2$. This discrete group accounts for the observed pattern of fermion masses and mixing angles after spontaneous symmetry breaking. In this scenario only the third generation of fermions get their masses as in the Standard Model (SM). The masses of the remaining fermions are generated through a seesaw-like mechanism. To that end, the matter content of the model is enlarged by introducing electrically charged vector-like fermions (VLFs), right handed Majorana neutrinos and several SM scalar singlets. Here we study the processes involving VLFs that are within the reach of the Large Hadron Collider (LHC). We perform collider studies for vector-like leptons (VLLs) and vector-like quarks (VLQs), focusing on double production channels for both cases, while for VLLs single production topologies are also included. Utilizing genetic algorithms for neural network optimization, we determine the statistical significance for a hypothetical discovery at future LHC runs. In particular, we show that we can not safely exclude VLLs for masses greater than $200~\mathrm{GeV}$. For VLQ's in our model, we show that we can probe their masses up to 3.8 TeV, if we take only into account the high-luminosity phase of the LHC. Considering Run-III luminosities, we can also exclude VLQs for masses up to $3.4~\mathrm{TeV}$. We also show how the model with predicted VLL masses accommodates the muon anomalous magnetic moment. |
2201.12877 | Nikolaos Kidonakis | Nikolaos Kidonakis and Nodoka Yamanaka | QCD corrections in $tq\gamma$ production at hadron colliders | 15 pages, 7 figures, 10 tables; v2 has a lot of additional new
material | Eur. Phys. J. C 82, 670 (2022) | 10.1140/epjc/s10052-022-10643-z | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study QCD corrections for the associated production of a single top quark
and a photon ($tq\gamma$ production) at hadron colliders. We calculate the NLO
cross section at LHC and future collider energies for a variety of kinematical
cuts, and we estimate uncertainties from scale dependence and from parton
distributions. We also calculate differential distributions in top-quark
transverse-momentum and rapidity as well as photon energy. Finally, we study
higher-order corrections from soft-gluon emission for this process, and we
provide approximate NNLO (aNNLO) results for the cross section and top-quark
differential distributions. We also compare our calculations with recent
measurements from CMS and ATLAS at the LHC and find that the aNNLO corrections
improve the comparison between the data and the Standard Model predictions.
| [
{
"created": "Sun, 30 Jan 2022 17:00:53 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Jun 2022 15:01:47 GMT",
"version": "v2"
}
] | 2022-08-08 | [
[
"Kidonakis",
"Nikolaos",
""
],
[
"Yamanaka",
"Nodoka",
""
]
] | We study QCD corrections for the associated production of a single top quark and a photon ($tq\gamma$ production) at hadron colliders. We calculate the NLO cross section at LHC and future collider energies for a variety of kinematical cuts, and we estimate uncertainties from scale dependence and from parton distributions. We also calculate differential distributions in top-quark transverse-momentum and rapidity as well as photon energy. Finally, we study higher-order corrections from soft-gluon emission for this process, and we provide approximate NNLO (aNNLO) results for the cross section and top-quark differential distributions. We also compare our calculations with recent measurements from CMS and ATLAS at the LHC and find that the aNNLO corrections improve the comparison between the data and the Standard Model predictions. |
hep-ph/0607057 | Stefan H\"oche | Claude Duhr and Stefan Hoeche and Fabio Maltoni | Color-dressed recursive relations for multi-parton amplitudes | 31 pages, 4 figures, 6 tables | JHEP 0608:062,2006 | 10.1088/1126-6708/2006/08/062 | CP3-06-02 | hep-ph hep-th | null | Remarkable progress inspired by twistors has lead to very simple analytic
expressions and to new recursive relations for multi-parton color-ordered
amplitudes. We show how such relations can be extended to include color and
present the corresponding color-dressed formulation for the Berends-Giele, BCF
and a new kind of CSW recursive relations. A detailed comparison of the
numerical efficiency of the different approaches to the calculation of
multi-parton cross sections is performed.
| [
{
"created": "Wed, 5 Jul 2006 17:24:11 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Duhr",
"Claude",
""
],
[
"Hoeche",
"Stefan",
""
],
[
"Maltoni",
"Fabio",
""
]
] | Remarkable progress inspired by twistors has lead to very simple analytic expressions and to new recursive relations for multi-parton color-ordered amplitudes. We show how such relations can be extended to include color and present the corresponding color-dressed formulation for the Berends-Giele, BCF and a new kind of CSW recursive relations. A detailed comparison of the numerical efficiency of the different approaches to the calculation of multi-parton cross sections is performed. |
hep-ph/0408329 | Yasunori Nomura | Andreas Birkedal, Z. Chacko, Yasunori Nomura | Relaxing the Upper Bound on the Mass of the Lightest Supersymmetric
Higgs Boson | 20 pages, 2 figures, version to appear in Phys. Rev. D | Phys.Rev.D71:015006,2005 | 10.1103/PhysRevD.71.015006 | UFIFT-HEP-04-4, CLNS 04/1881, UCB-PTH 04/17, LBNL-55247 | hep-ph hep-th | null | We present a class of supersymmetric models in which the lightest Higgs-boson
mass can be as large as a few hundred GeV (200 - 300 GeV) while the successful
MSSM prediction for gauge coupling unification is preserved. The theories are
formulated on a 5D warped space truncated by two branes, and a part of the
Higgs sector is localized on the infrared brane. The structure of the Higgs
sector in the four dimensional effective theory below the Kaluza-Klein mass
scale is essentially that of the next-to-minimal supersymmetric standard model
(NMSSM), or related theories. However, large values of the NMSSM couplings at
the weak scale are now possible as these couplings are required to be
perturbative only up to the infrared cutoff scale, which can in general be much
lower than the unification scale. This allows the possibility of generating a
large quartic coupling in the Higgs potential, and thereby significantly
raising the Higgs-boson mass bound. We present two particularly simple models.
In the first model, the quark and lepton fields are localized on the
ultraviolet brane, where the grand unified symmetry is broken. In the second
model, the quark and lepton fields are localized on the infrared brane, and the
unified symmetry is broken both on the ultraviolet and infrared branes. Our
theories potentially allow the possibility of a significant reduction in the
fine-tuning needed for correct electroweak symmetry breaking, although this is
somewhat model dependent.
| [
{
"created": "Mon, 30 Aug 2004 07:02:21 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Jan 2005 02:00:05 GMT",
"version": "v2"
}
] | 2009-09-29 | [
[
"Birkedal",
"Andreas",
""
],
[
"Chacko",
"Z.",
""
],
[
"Nomura",
"Yasunori",
""
]
] | We present a class of supersymmetric models in which the lightest Higgs-boson mass can be as large as a few hundred GeV (200 - 300 GeV) while the successful MSSM prediction for gauge coupling unification is preserved. The theories are formulated on a 5D warped space truncated by two branes, and a part of the Higgs sector is localized on the infrared brane. The structure of the Higgs sector in the four dimensional effective theory below the Kaluza-Klein mass scale is essentially that of the next-to-minimal supersymmetric standard model (NMSSM), or related theories. However, large values of the NMSSM couplings at the weak scale are now possible as these couplings are required to be perturbative only up to the infrared cutoff scale, which can in general be much lower than the unification scale. This allows the possibility of generating a large quartic coupling in the Higgs potential, and thereby significantly raising the Higgs-boson mass bound. We present two particularly simple models. In the first model, the quark and lepton fields are localized on the ultraviolet brane, where the grand unified symmetry is broken. In the second model, the quark and lepton fields are localized on the infrared brane, and the unified symmetry is broken both on the ultraviolet and infrared branes. Our theories potentially allow the possibility of a significant reduction in the fine-tuning needed for correct electroweak symmetry breaking, although this is somewhat model dependent. |
1402.7065 | Susanne Westhoff | Ayres Freitas, Joseph Lykken, Stefan Kell, Susanne Westhoff | Testing the Muon g-2 Anomaly at the LHC | 35 pages, 7 figures, 7 tables, corrected bounds from electron g-2 on
effects of mixing vector fermions in Section 4 | JHEP 1405 (2014) 145 | 10.1007/JHEP05(2014)145 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The long-standing difference between the experimental measurement and the
standard-model prediction for the muon's anomalous magnetic moment, $a_{\mu} =
(g_{\mu}-2)/2$, may be explained by the presence of new weakly interacting
particles with masses of a few 100 GeV. Particles of this kind can generally be
directly produced at the LHC, and thus they may already be constrained by
existing data. In this work, we investigate this connection between $a_{\mu}$
and the LHC in a model-independent approach, by introducing one or two new
fields beyond the standard model with spin and weak isospin up to one. For each
case, we identify the preferred parameter space for explaining the discrepancy
of a_mu and derive bounds using data from LEP and the 8-TeV LHC run.
Furthermore, we estimate how these limits could be improved with the 14-TeV
LHC. We find that the 8-TeV results already rule out a subset of our simplified
models, while almost all viable scenarios can be tested conclusively with
14-TeV data.
| [
{
"created": "Thu, 27 Feb 2014 20:49:51 GMT",
"version": "v1"
},
{
"created": "Fri, 6 Jun 2014 13:13:19 GMT",
"version": "v2"
},
{
"created": "Fri, 12 Sep 2014 19:54:41 GMT",
"version": "v3"
}
] | 2015-06-18 | [
[
"Freitas",
"Ayres",
""
],
[
"Lykken",
"Joseph",
""
],
[
"Kell",
"Stefan",
""
],
[
"Westhoff",
"Susanne",
""
]
] | The long-standing difference between the experimental measurement and the standard-model prediction for the muon's anomalous magnetic moment, $a_{\mu} = (g_{\mu}-2)/2$, may be explained by the presence of new weakly interacting particles with masses of a few 100 GeV. Particles of this kind can generally be directly produced at the LHC, and thus they may already be constrained by existing data. In this work, we investigate this connection between $a_{\mu}$ and the LHC in a model-independent approach, by introducing one or two new fields beyond the standard model with spin and weak isospin up to one. For each case, we identify the preferred parameter space for explaining the discrepancy of a_mu and derive bounds using data from LEP and the 8-TeV LHC run. Furthermore, we estimate how these limits could be improved with the 14-TeV LHC. We find that the 8-TeV results already rule out a subset of our simplified models, while almost all viable scenarios can be tested conclusively with 14-TeV data. |
hep-ph/0508004 | Max Metlitski A | Max A. Metlitski and Ariel R. Zhitnitsky | $\theta-$ Parameter in 2 Color QCD at Finite Baryon and Isospin Density | null | Nucl.Phys. B731 (2005) 309-334 | 10.1016/j.nuclphysb.2005.09.027 | null | hep-ph hep-lat hep-th | null | We use 2-color QCD as a model to study the effects of simultaneous presence
of the so-called $\theta$ parameter, chemical potentials for baryon number,
$\mu_B$ and for isospin charge, $\mu_I$. We pay special attention to $\theta$,
$\mu_B$, $\mu_I$ dependence of different vacuum condensates, including chiral
and diquark condensates, as well as the gluon condensate, $<G^2>$, and the
topological susceptibility. We find that two phase transitions of the second
order will occur when $\theta$ relaxes from $\theta=2\pi$ to $\theta=0$, if
$\mu$ is of order of the pion mass. We demonstrate that the transition to the
superfluid phase at $\theta = \pi$ occurs at a much lower chemical potential
than at $\theta = 0$. We also show that the strong $\theta$ dependence present
near $\theta = \pi$ in vacuum (Dashen's phenomenon), becomes smoothed out in
the superfluid phase. Finally, we comment on the relevance of this study for
the real world with N_c=3.
| [
{
"created": "Sat, 30 Jul 2005 20:29:46 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Metlitski",
"Max A.",
""
],
[
"Zhitnitsky",
"Ariel R.",
""
]
] | We use 2-color QCD as a model to study the effects of simultaneous presence of the so-called $\theta$ parameter, chemical potentials for baryon number, $\mu_B$ and for isospin charge, $\mu_I$. We pay special attention to $\theta$, $\mu_B$, $\mu_I$ dependence of different vacuum condensates, including chiral and diquark condensates, as well as the gluon condensate, $<G^2>$, and the topological susceptibility. We find that two phase transitions of the second order will occur when $\theta$ relaxes from $\theta=2\pi$ to $\theta=0$, if $\mu$ is of order of the pion mass. We demonstrate that the transition to the superfluid phase at $\theta = \pi$ occurs at a much lower chemical potential than at $\theta = 0$. We also show that the strong $\theta$ dependence present near $\theta = \pi$ in vacuum (Dashen's phenomenon), becomes smoothed out in the superfluid phase. Finally, we comment on the relevance of this study for the real world with N_c=3. |
1807.11508 | Sebastian Ellis | Nikita Blinov, Sebastian A. R. Ellis, Anson Hook | Consequences of Fine-Tuning for Fifth Force Searches | 36 pages, 9 figures -- v3 reflects version published in JHEP | JHEP 1811 (2018) 029 | 10.1007/JHEP11(2018)029 | SLAC-PUB-17311 | hep-ph astro-ph.CO gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Light bosonic fields mediate long range forces between objects. If these
fields have self-interactions, i.e., non-quadratic terms in the potential, the
experimental constraints on such forces can be drastically altered due to a
screening (chameleon) or enhancement effect. We explore how technically natural
values for such self-interaction coupling constants modify the existing
constraints. We point out that assuming the existence of these natural
interactions leads to new constraints, contrary to the usual expectation that
screening leads to gaps in coverage. We discuss how screening can turn
fundamentally equivalence principle (EP)-preserving forces into EP-violating
ones. This means that when natural screening is present, searches for EP
violation can be used to constrain EP-preserving forces. We show how this
effect enables the recently discovered stellar triple system \textit{PSR
J0337$+$1715} to place a powerful constraint on EP-preserving fifth forces.
Finally, we demonstrate that technically natural cubic self-interactions modify
the vacuum structure of the scalar potential, leading to new constraints from
spontaneous and induced vacuum decay.
| [
{
"created": "Mon, 30 Jul 2018 18:03:31 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Aug 2018 16:36:32 GMT",
"version": "v2"
},
{
"created": "Tue, 4 Dec 2018 00:38:39 GMT",
"version": "v3"
}
] | 2018-12-05 | [
[
"Blinov",
"Nikita",
""
],
[
"Ellis",
"Sebastian A. R.",
""
],
[
"Hook",
"Anson",
""
]
] | Light bosonic fields mediate long range forces between objects. If these fields have self-interactions, i.e., non-quadratic terms in the potential, the experimental constraints on such forces can be drastically altered due to a screening (chameleon) or enhancement effect. We explore how technically natural values for such self-interaction coupling constants modify the existing constraints. We point out that assuming the existence of these natural interactions leads to new constraints, contrary to the usual expectation that screening leads to gaps in coverage. We discuss how screening can turn fundamentally equivalence principle (EP)-preserving forces into EP-violating ones. This means that when natural screening is present, searches for EP violation can be used to constrain EP-preserving forces. We show how this effect enables the recently discovered stellar triple system \textit{PSR J0337$+$1715} to place a powerful constraint on EP-preserving fifth forces. Finally, we demonstrate that technically natural cubic self-interactions modify the vacuum structure of the scalar potential, leading to new constraints from spontaneous and induced vacuum decay. |
hep-ph/9912225 | Emilio Torrente Lujan | E. Torrente-Lujan | Influence of solar chaotic magnetic fields on neutrino oscillations | 10pp+2figs. To be published in the proceedings of 2nd ICRA Network
Workshop: The Chaotic Universe: Theory and observations, Rome, Italy, 1-5 Feb
1999 | null | null | IFIC/FTUV-9923 | hep-ph | null | We consider the effect of a random magnetic field in the convective zone of
the Sun on resonant neutrino spin-flavour oscillations. The expected signals in
the different experiments (SK, GALLEX-SAGE,Homestake) are obtained as a
function of the level of noise, regular magnetic field and neutrino mixing
parameters. Previous results obtained for small mixing and ad-hoc regular
magnetic profiles are reobtained. We find that
MSW regions are stable up to very large levels of noise
(P=0.7-0.8) and they are acceptable from the point of view of antineutrino
production. For strong noise any parameter region $(\Delta m^2, \sin^2
2\theta)$ is excluded: this model of noisy magnetic field is not compatible
with particle physics solutions to the SNP. scenario.
| [
{
"created": "Thu, 2 Dec 1999 21:18:35 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Torrente-Lujan",
"E.",
""
]
] | We consider the effect of a random magnetic field in the convective zone of the Sun on resonant neutrino spin-flavour oscillations. The expected signals in the different experiments (SK, GALLEX-SAGE,Homestake) are obtained as a function of the level of noise, regular magnetic field and neutrino mixing parameters. Previous results obtained for small mixing and ad-hoc regular magnetic profiles are reobtained. We find that MSW regions are stable up to very large levels of noise (P=0.7-0.8) and they are acceptable from the point of view of antineutrino production. For strong noise any parameter region $(\Delta m^2, \sin^2 2\theta)$ is excluded: this model of noisy magnetic field is not compatible with particle physics solutions to the SNP. scenario. |
hep-ph/9611355 | Lou Clavelli | L. Clavelli, P.W. Coulter and L.R. Surguladze | Gluino Contribution to the 3-loop QCD beta function in the Minimal
Supersymmetric Standard Model | 11 pages, RevTex, 4 Postscript figure | Phys.Rev. D55 (1997) 4268-4272 | 10.1103/PhysRevD.55.4268 | UAHEP9611 | hep-ph | null | We deduce the gluino contribution to the three-loop QCD \beta function within
the minimal supersymmetric Standard Model (MSSM) from its standard QCD
expression. The result is a first step in the computation of the full MSSM
three-loop \beta function. In addition, in the case of a light gluino it
provides the strong three-loop SUSY correction to the extrapolation of the
strong coupling constant from the low energy regime to the Z region and up to
the squark threshold.
| [
{
"created": "Tue, 19 Nov 1996 01:27:01 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Clavelli",
"L.",
""
],
[
"Coulter",
"P. W.",
""
],
[
"Surguladze",
"L. R.",
""
]
] | We deduce the gluino contribution to the three-loop QCD \beta function within the minimal supersymmetric Standard Model (MSSM) from its standard QCD expression. The result is a first step in the computation of the full MSSM three-loop \beta function. In addition, in the case of a light gluino it provides the strong three-loop SUSY correction to the extrapolation of the strong coupling constant from the low energy regime to the Z region and up to the squark threshold. |
hep-ph/9607340 | Leona Kershaw | R. D. McKeown | Should the Strange Magnetic Moment of the Nucleon be Positive? | 3 pages TEX, text also available at
http://www.krl.caltech.edu/preprints/MAP.html | null | null | MAP-202 | hep-ph | null | The strange magnetic moment of the nucleon ($\mu_s$) is examined as part of
the nucleon's isoscalar anomalous moment. The dominant up and down quark
effects in the anomalous moment may actually tend to favor $\mu_s >0$, which is
contrary to the negative values that generally result from model calculations.
The possible origins of this apparent discrepancy are considered.
| [
{
"created": "Tue, 16 Jul 1996 20:33:11 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Jul 1996 18:27:04 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"McKeown",
"R. D.",
""
]
] | The strange magnetic moment of the nucleon ($\mu_s$) is examined as part of the nucleon's isoscalar anomalous moment. The dominant up and down quark effects in the anomalous moment may actually tend to favor $\mu_s >0$, which is contrary to the negative values that generally result from model calculations. The possible origins of this apparent discrepancy are considered. |
2307.03098 | Ryan Moodie | Simon Badger, Jakub Kry\'s, Ryan Moodie, Simone Zoia | Lepton-pair scattering with an off-shell and an on-shell photon at two
loops in massless QED | 16 + 14 pages, 2 figures, 2 tables, 5 appendices. Ancillary files
also at https://doi.org/10.5281/zenodo.8120540 . v3: minor revision to
address referee report | null | 10.1007/JHEP11(2023)041 | null | hep-ph hep-th | http://creativecommons.org/licenses/by/4.0/ | We compute the two-loop QED helicity amplitudes for the scattering of a
lepton pair with an off-shell and an on-shell photon,
$0\to\ell\bar\ell\gamma\gamma^*$, using the approximation of massless leptons.
We express all master integrals relevant for the scattering of four massless
particles with a single external off-shell leg up to two loops in a basis of
algebraically independent multiple polylogarithms, which guarantees an
efficient numerical evaluation and compact analytic representations of the
amplitudes. Analytic forms of the amplitudes are reconstructed from numerical
evaluations over finite fields. Our results complete the amplitude-level
ingredients contributing to the N$^3$LO predictions of electron-muon scattering
$e\mu\to e\mu$, which are required to meet the precision goal of the future
MUonE experiment.
| [
{
"created": "Thu, 6 Jul 2023 16:14:18 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Jul 2023 08:36:27 GMT",
"version": "v2"
},
{
"created": "Thu, 19 Oct 2023 09:14:29 GMT",
"version": "v3"
}
] | 2023-11-10 | [
[
"Badger",
"Simon",
""
],
[
"Kryś",
"Jakub",
""
],
[
"Moodie",
"Ryan",
""
],
[
"Zoia",
"Simone",
""
]
] | We compute the two-loop QED helicity amplitudes for the scattering of a lepton pair with an off-shell and an on-shell photon, $0\to\ell\bar\ell\gamma\gamma^*$, using the approximation of massless leptons. We express all master integrals relevant for the scattering of four massless particles with a single external off-shell leg up to two loops in a basis of algebraically independent multiple polylogarithms, which guarantees an efficient numerical evaluation and compact analytic representations of the amplitudes. Analytic forms of the amplitudes are reconstructed from numerical evaluations over finite fields. Our results complete the amplitude-level ingredients contributing to the N$^3$LO predictions of electron-muon scattering $e\mu\to e\mu$, which are required to meet the precision goal of the future MUonE experiment. |
hep-ph/9902372 | Csaba Boros | C. Boros and A. W. Thomas | Parton Distributions for the Octet and Decuplet Baryons | 29 pages, 15 figures | Phys.Rev.D60:074017,1999 | 10.1103/PhysRevD.60.074017 | ADP-99-9/T354 | hep-ph | null | We calculate the parton distributions for both polarized and unpolarized
octet and decuplet baryons, using the MIT bag, dressed by mesons. We show that
the hyperfine interaction responsible for the $\Delta - N$ and $\Sigma^0 -
\Lambda$ splittings leads to large deviations from SU(3) and SU(6) predictions.
For the $\Lambda$ we find significant polarized, non-strange parton
distributions which lead to a sizable $\Lambda$ polarization in polarized,
semi-inclusive $ep$ scattering. We also discuss the flavour symmetry violation
arising from the meson-cloud associated with the chiral structure of baryons.
| [
{
"created": "Wed, 17 Feb 1999 05:15:49 GMT",
"version": "v1"
}
] | 2010-02-17 | [
[
"Boros",
"C.",
""
],
[
"Thomas",
"A. W.",
""
]
] | We calculate the parton distributions for both polarized and unpolarized octet and decuplet baryons, using the MIT bag, dressed by mesons. We show that the hyperfine interaction responsible for the $\Delta - N$ and $\Sigma^0 - \Lambda$ splittings leads to large deviations from SU(3) and SU(6) predictions. For the $\Lambda$ we find significant polarized, non-strange parton distributions which lead to a sizable $\Lambda$ polarization in polarized, semi-inclusive $ep$ scattering. We also discuss the flavour symmetry violation arising from the meson-cloud associated with the chiral structure of baryons. |
hep-ph/9401277 | Hubert Simma | A. Ali, V.M. Braun, H. Simma | Exclusive Radiative B-Decays in the Light-Cone QCD Sum Rule Approach | 32 pages, 10 uuencoded figures, LaTeX, preprint CERN-TH 7118/93 | Z.Phys.C63:437-454,1994 | 10.1007/BF01580324 | null | hep-ph | null | We carry out a detailed study of exclusive radiative rare $B$-decays in the
framework of the QCD sum rules on the light cone, which combines the
traditional QCD sum rule technique with the description of final state vector
mesons in terms of the light-cone wave functions of increasing twist. The
decays considered are: $B_{u,d} \to K^* +\gamma, B_{u,d}\to \rho+\gamma, B_d\to
\omega+\gamma$ and the corresponding decays of the $B_s$ mesons, $B_s\to
\phi+\gamma$ and $B_s\to K^*+\gamma$. Based on our estimate of the transition
form factor $F_1^{B \to K^*\pg}(0) =0.32\pm0.05$, we find for the branching
ratio $BR(B \to K^* + \gamma) = (4.8\pm 1.5)\times 10^{-5}$, which is in
agreement with the observed value measured by the CLEO collaboration. We
present detailed estimates for the ratios of the radiative decay form factors,
which are then used to predict the rates for the exclusive radiative B-decays
listed above. This in principle allows the extraction of the CKM matrix element
$|V_{td}|$ from the penguin-dominated CKM-suppressed radiative decays when they
are measured. We give a detailed discussion of the dependence of the form
factors on the $b$-quark mass and on the momentum transfer, as well as their
interrelation with the CKM-suppressed semileptonic decay form factors in $B\to
\rho+\ell+\nu$, which we also calculate in our approach.
| [
{
"created": "Tue, 18 Jan 1994 12:56:53 GMT",
"version": "v1"
}
] | 2010-11-01 | [
[
"Ali",
"A.",
""
],
[
"Braun",
"V. M.",
""
],
[
"Simma",
"H.",
""
]
] | We carry out a detailed study of exclusive radiative rare $B$-decays in the framework of the QCD sum rules on the light cone, which combines the traditional QCD sum rule technique with the description of final state vector mesons in terms of the light-cone wave functions of increasing twist. The decays considered are: $B_{u,d} \to K^* +\gamma, B_{u,d}\to \rho+\gamma, B_d\to \omega+\gamma$ and the corresponding decays of the $B_s$ mesons, $B_s\to \phi+\gamma$ and $B_s\to K^*+\gamma$. Based on our estimate of the transition form factor $F_1^{B \to K^*\pg}(0) =0.32\pm0.05$, we find for the branching ratio $BR(B \to K^* + \gamma) = (4.8\pm 1.5)\times 10^{-5}$, which is in agreement with the observed value measured by the CLEO collaboration. We present detailed estimates for the ratios of the radiative decay form factors, which are then used to predict the rates for the exclusive radiative B-decays listed above. This in principle allows the extraction of the CKM matrix element $|V_{td}|$ from the penguin-dominated CKM-suppressed radiative decays when they are measured. We give a detailed discussion of the dependence of the form factors on the $b$-quark mass and on the momentum transfer, as well as their interrelation with the CKM-suppressed semileptonic decay form factors in $B\to \rho+\ell+\nu$, which we also calculate in our approach. |
0706.3303 | Victor Abramovsky | A.V. Dmitriev, N.V.Radchenko | Soft colour interactions in hadron-hadron hard diffraction | 5 pages, 3 figures | null | null | null | hep-ph | null | SCI model gives a good and natural description of DDIS cross-sections.
Howevere, this model is pure phenomenological, and does not explain the nature
of soft color rearrangment. In this paper we argue, that the most capabilities
of SCI model can be derived from low constituent model and overview
applicability of low constituent model to DDIS processes.
| [
{
"created": "Fri, 22 Jun 2007 10:17:21 GMT",
"version": "v1"
}
] | 2007-06-25 | [
[
"Dmitriev",
"A. V.",
""
],
[
"Radchenko",
"N. V.",
""
]
] | SCI model gives a good and natural description of DDIS cross-sections. Howevere, this model is pure phenomenological, and does not explain the nature of soft color rearrangment. In this paper we argue, that the most capabilities of SCI model can be derived from low constituent model and overview applicability of low constituent model to DDIS processes. |
1410.1081 | Brigitte Hiller | A. A. Osipov, B. Hiller, A. H. Blin | Effective Lagrangian approach to multi-quark interactions | 4 p, prepared for the Workshop Bled 2014: "Quark masses and Hadron
spectra",Bled (Slovenia), July 6-13, 2014 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this workshop we have presented the results obtained in the three-flavour
($N_f=3$) Nambu--Jona-Lasinio model Lagrangian which includes all
non-derivative vertices at NLO in the $1/N_c$ expansion of spin zero
multi-quark interactions. In particular the role played by the explicit chiral
symmetry breaking interactions has been discussed in comparison with previous
model Lagrangians.
| [
{
"created": "Sat, 4 Oct 2014 19:03:10 GMT",
"version": "v1"
}
] | 2014-10-07 | [
[
"Osipov",
"A. A.",
""
],
[
"Hiller",
"B.",
""
],
[
"Blin",
"A. H.",
""
]
] | In this workshop we have presented the results obtained in the three-flavour ($N_f=3$) Nambu--Jona-Lasinio model Lagrangian which includes all non-derivative vertices at NLO in the $1/N_c$ expansion of spin zero multi-quark interactions. In particular the role played by the explicit chiral symmetry breaking interactions has been discussed in comparison with previous model Lagrangians. |
hep-ph/0701029 | Jean Cleymans | F. Becattini and J. Cleymans | Chemical Equilibrium in Heavy Ion Collisions: Rapidity Dependence | 5 pages, 4 figures | J.Phys.G34:S959-964,2007 | 10.1088/0954-3899/34/8/S135 | null | hep-ph | null | Particle yields in heavy ion collisions show an overwhelming evidence for
chemical or relative chemical equilibrium at all beam energies. The rapidity
dependence of the thermal parameters $T$ and $\mu_B$ can now be determined over
a wide range of rapidities and show a systematic behavior towards an increase
in $\mu_B$ away from mid-rapidity.
| [
{
"created": "Thu, 4 Jan 2007 12:58:47 GMT",
"version": "v1"
},
{
"created": "Fri, 5 Jan 2007 13:37:31 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Becattini",
"F.",
""
],
[
"Cleymans",
"J.",
""
]
] | Particle yields in heavy ion collisions show an overwhelming evidence for chemical or relative chemical equilibrium at all beam energies. The rapidity dependence of the thermal parameters $T$ and $\mu_B$ can now be determined over a wide range of rapidities and show a systematic behavior towards an increase in $\mu_B$ away from mid-rapidity. |
hep-ph/0601173 | Yu Jia | Yu Jia | Model-independent Study on Magnetic Dipole Transition in Heavy
Quarkonium | 7 pages and 3 figures. Talk presented at QCD@Work 2005, Conversano,
June 16-20, 2005 and QCD05, Montpellier, July 4-8, 2005 | null | 10.1063/1.2163768 | IFUM-861-FT | hep-ph | null | Some new results on magnetic dipole (M1) transitions in heavy quarkonium from
nonrelativistic effective field theories of QCD are briefly reported. This
model-independent approach not only facilitates a systematic and lucid way to
investigate the relativistic corrections, it also clarifies some inconsistent
treatment in previous potential model approach. The impact of our formalism on
J/Psi -> eta_c gamma, Upsilon(Upsilon') -> eta_b gamma and h_c -> chi_{c0}
gamma are discussed.
| [
{
"created": "Fri, 20 Jan 2006 13:12:09 GMT",
"version": "v1"
},
{
"created": "Sun, 22 Jan 2006 11:14:28 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Jia",
"Yu",
""
]
] | Some new results on magnetic dipole (M1) transitions in heavy quarkonium from nonrelativistic effective field theories of QCD are briefly reported. This model-independent approach not only facilitates a systematic and lucid way to investigate the relativistic corrections, it also clarifies some inconsistent treatment in previous potential model approach. The impact of our formalism on J/Psi -> eta_c gamma, Upsilon(Upsilon') -> eta_b gamma and h_c -> chi_{c0} gamma are discussed. |
2204.04559 | Manuel Gonzalez-Lopez | Mattias Blennow, Pilar Coloma, Enrique Fern\'andez-Mart\'inez, Manuel
Gonz\'alez-L\'opez | Right-handed neutrinos and the CDF II anomaly | 5 pages, 1 figure, REVTeX4 | null | null | IFT-UAM/CSIC-22-42 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We point out that right-handed neutrinos can resolve the tension between the
latest CDF II measurement of the $W$-boson mass, $M_W$, and the standard model.
Integrating out the new states yields a single $d=6$ operator, which induces a
deviation from unitarity in the PMNS matrix. This alters the extraction of the
Fermi constant from muon decay and increases the prediction for $M_W$, in line
with the CDF II result. Non-unitarity of the PMNS matrix would also affect
beta, meson, and tau decays. We find that the CDF II value for $M_W$ can be
explained without conflicting with lepton flavour universality constraints or
the invisible decay width of the $Z$. However, the so-called Cabibbo angle
anomaly is worsened if right-handed neutrinos are the origin of the $d=6$
operator. The situation improves if the operator coefficient is left
unconstrained, implying additional sources of new physics, but a common
explanation of both anomalies is in tension with universality bounds.
| [
{
"created": "Sat, 9 Apr 2022 22:12:03 GMT",
"version": "v1"
},
{
"created": "Tue, 3 May 2022 10:16:03 GMT",
"version": "v2"
}
] | 2022-05-04 | [
[
"Blennow",
"Mattias",
""
],
[
"Coloma",
"Pilar",
""
],
[
"Fernández-Martínez",
"Enrique",
""
],
[
"González-López",
"Manuel",
""
]
] | We point out that right-handed neutrinos can resolve the tension between the latest CDF II measurement of the $W$-boson mass, $M_W$, and the standard model. Integrating out the new states yields a single $d=6$ operator, which induces a deviation from unitarity in the PMNS matrix. This alters the extraction of the Fermi constant from muon decay and increases the prediction for $M_W$, in line with the CDF II result. Non-unitarity of the PMNS matrix would also affect beta, meson, and tau decays. We find that the CDF II value for $M_W$ can be explained without conflicting with lepton flavour universality constraints or the invisible decay width of the $Z$. However, the so-called Cabibbo angle anomaly is worsened if right-handed neutrinos are the origin of the $d=6$ operator. The situation improves if the operator coefficient is left unconstrained, implying additional sources of new physics, but a common explanation of both anomalies is in tension with universality bounds. |
hep-ph/9602410 | Tom Mehen | Thomas Mehen (Johns Hopkins University) | Scale Setting in Top Quark Decays | Uses REVTEX, 9 pages, 4 EPS figures embedded with epsf.sty Some
references and 1 figure added, conclusions slightly modified, numerical
results unchanged. Version accepted for publication in Physics Letters B | Phys.Lett. B382 (1996) 267-272 | 10.1016/0370-2693(96)00681-8 | JHU-TIPAC-96004 | hep-ph | null | We compute the $O(\beta_0 \alpha_s^2)$ QCD corrections to the Standard Model
decay $t\rightarrow W^+ b$ as well as the non standard decay $t\rightarrow H^+
b$. We then use our results to compute the BLM scale for these decays, and
study the dependence of the BLM scale on the mass of the boson in the decay. We
find that the BLM procedure gives extremely small scales when top decays into
heavy bosons. When we try to improve the BLM scale by reexpressing rates as a
functions of the top quark running mass, we find the BLM scale exhibits
unnatural dependence on the boson mass, casting doubts on the applicability of
the BLM procedure to these processes.
| [
{
"created": "Tue, 27 Feb 1996 19:34:53 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Jun 1996 21:13:39 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Mehen",
"Thomas",
"",
"Johns Hopkins University"
]
] | We compute the $O(\beta_0 \alpha_s^2)$ QCD corrections to the Standard Model decay $t\rightarrow W^+ b$ as well as the non standard decay $t\rightarrow H^+ b$. We then use our results to compute the BLM scale for these decays, and study the dependence of the BLM scale on the mass of the boson in the decay. We find that the BLM procedure gives extremely small scales when top decays into heavy bosons. When we try to improve the BLM scale by reexpressing rates as a functions of the top quark running mass, we find the BLM scale exhibits unnatural dependence on the boson mass, casting doubts on the applicability of the BLM procedure to these processes. |
1508.01529 | Stefano Forte | Stefano Forte, Davide Napoletano and Maria Ubiali | Higgs production in bottom-quark fusion in a matched scheme | 15 pages, 4 figures; three typos corrected. Final version, to be
published in Phys. Lett. B | null | 10.1016/j.physletb.2015.10.051 | TIF-UNIMI-2015-12, Cavendish-HEP-15/06 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the total cross-section for Higgs boson production in bottom-quark
fusion using the so-called FONLL method for the matching of a scheme in which
the $b$-quark is treated as a massless parton to that in which it is treated as
a massive final-state particle. We discuss the general framework for the
application of the FONLL method to this process, and then we present explicit
expressions for the case in which the next-to-next-to-leading-log five-flavor
scheme result is combined with the leading-order $\cal O(\alpha_s^2)$
four-flavor scheme computation. We compare our results in this case to the
four-and five-flavor scheme computations, and to the so-called Santander
matching.
| [
{
"created": "Thu, 6 Aug 2015 20:12:02 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Oct 2015 17:23:29 GMT",
"version": "v2"
}
] | 2015-10-28 | [
[
"Forte",
"Stefano",
""
],
[
"Napoletano",
"Davide",
""
],
[
"Ubiali",
"Maria",
""
]
] | We compute the total cross-section for Higgs boson production in bottom-quark fusion using the so-called FONLL method for the matching of a scheme in which the $b$-quark is treated as a massless parton to that in which it is treated as a massive final-state particle. We discuss the general framework for the application of the FONLL method to this process, and then we present explicit expressions for the case in which the next-to-next-to-leading-log five-flavor scheme result is combined with the leading-order $\cal O(\alpha_s^2)$ four-flavor scheme computation. We compare our results in this case to the four-and five-flavor scheme computations, and to the so-called Santander matching. |
hep-ph/9406375 | Nobuhiro Maekawa | Nobuhiro Maekawa | Vector-like Strong Coupling theory with small S and T parameters | null | Prog.Theor.Phys. 93 (1995) 919-926 | 10.1143/ptp/93.5.919 | null | hep-ph | null | We propose a mechanism which can reduce the Peskin and Takeuchi's S, T and U
parameters in dynamical electroweak symmetry breaking models. It is interesting
that not only S but also T parameter can become small even if there exists
large isospin violation in fermion condensation. For example, when we take the
$SU(2)_L\times U(1)_Y$ breaking mass of up-type fermion $m_U=1$ TeV and that of
down-type $m_D=0$, we get S$\sim 0.001 N$ and T$\sim 0.05 N$ for the
$SU(2)_L\times U(1)_Y$ invariant masses $M=10$ TeV. The point is that these
parameters are suppressed by $SU(2)_L\times U(1)_Y$ invariant masses which the
vector-like fermions can have.
| [
{
"created": "Thu, 23 Jun 1994 11:15:49 GMT",
"version": "v1"
}
] | 2017-02-01 | [
[
"Maekawa",
"Nobuhiro",
""
]
] | We propose a mechanism which can reduce the Peskin and Takeuchi's S, T and U parameters in dynamical electroweak symmetry breaking models. It is interesting that not only S but also T parameter can become small even if there exists large isospin violation in fermion condensation. For example, when we take the $SU(2)_L\times U(1)_Y$ breaking mass of up-type fermion $m_U=1$ TeV and that of down-type $m_D=0$, we get S$\sim 0.001 N$ and T$\sim 0.05 N$ for the $SU(2)_L\times U(1)_Y$ invariant masses $M=10$ TeV. The point is that these parameters are suppressed by $SU(2)_L\times U(1)_Y$ invariant masses which the vector-like fermions can have. |
hep-ph/9711405 | Johannes Bluemlein | J. Bl\"umlein, B. Geyer, and D. Robaschik | Twist-2 Light-Ray Operators: Anomalous Dimensions and Evolution
Equations | 14 pages latex, Contribution to the Proceedings of the Int. Workshop
Deep Inelastic Scattering off Polarized Targets : Theory Meets Experiment,
September 1--5, 1997, DESY--Zeuthen, Germany; 3 typos corrected | null | null | DESY 97--209 | hep-ph | null | The non-singlet and singlet anomalous dimensions of the twist--2 light-ray
operators for unpolarized and polarized deep inelastic scattering are
calculated in $O(\alpha_s)$. We apply these results for the derivation of
evolution equations for partition functions, structure functions, and wave
functions which are defined as Fourier transforms of the matrix elements of the
light-ray operators. Special cases are the Altarelli-Parisi and Brodsky-Lepage
kernels. Finally we extend Radyushkin's solution from the non-singlet to the
singlet case.
| [
{
"created": "Thu, 20 Nov 1997 15:59:28 GMT",
"version": "v1"
},
{
"created": "Tue, 25 Nov 1997 08:05:39 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Blümlein",
"J.",
""
],
[
"Geyer",
"B.",
""
],
[
"Robaschik",
"D.",
""
]
] | The non-singlet and singlet anomalous dimensions of the twist--2 light-ray operators for unpolarized and polarized deep inelastic scattering are calculated in $O(\alpha_s)$. We apply these results for the derivation of evolution equations for partition functions, structure functions, and wave functions which are defined as Fourier transforms of the matrix elements of the light-ray operators. Special cases are the Altarelli-Parisi and Brodsky-Lepage kernels. Finally we extend Radyushkin's solution from the non-singlet to the singlet case. |
hep-ph/9708472 | Kari Eskola | K.J. Eskola | Pre-thermalization dynamics: initial conditions for QGP at the LHC and
RHIC from perturbative QCD | 11 pages, including 2 figures. A lecture at the International School
on the Physics of Quark Gluon Plasma, June 3-6, 1997, Hiroshima | Prog.Theor.Phys.Suppl. 129 (1997) 1-10 | 10.1143/PTPS.129.1 | CERN-TH/97-220 | hep-ph nucl-th | null | I discuss how the initial conditions for QGP-production in ultrarelativistic
heavy ion collisions at the LHC and RHIC can be computed from perturbative QCD.
| [
{
"created": "Wed, 27 Aug 1997 13:28:41 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Eskola",
"K. J.",
""
]
] | I discuss how the initial conditions for QGP-production in ultrarelativistic heavy ion collisions at the LHC and RHIC can be computed from perturbative QCD. |
hep-ph/0111298 | Kin-ya Oda | Kin-ya Oda and Nobuchika Okada | Alternative Signature of TeV Strings | a note added; version to appear in Phys. Rev. D; 11 pages, 1 eps
figure, LaTeX2e; BibTeX with utphys style used | Phys.Rev. D66 (2002) 095005 | 10.1103/PhysRevD.66.095005 | KEK-TH-790, UMD-PP-02-022 | hep-ph hep-ex hep-th | null | In string theory, it is well known that any hard scattering amplitude
inevitably suffers exponential suppression. We demonstrate that, if the string
scale is M_s < 2TeV, this intrinsically stringy behavior leads to a dramatic
reduction in the QCD jet production rate with very high transverse momenta p_T
> 2TeV at LHC. This suppression is sufficient to be observed in the first year
of low-luminosity running. Our prediction is based on the universal behavior of
string theory, and therefore is qualitatively model-independent. This signature
is alternative and complementary to conventional ones such as Regge resonance
(or string ball/black hole) production.
| [
{
"created": "Fri, 23 Nov 2001 06:15:49 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Sep 2002 08:00:33 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Oda",
"Kin-ya",
""
],
[
"Okada",
"Nobuchika",
""
]
] | In string theory, it is well known that any hard scattering amplitude inevitably suffers exponential suppression. We demonstrate that, if the string scale is M_s < 2TeV, this intrinsically stringy behavior leads to a dramatic reduction in the QCD jet production rate with very high transverse momenta p_T > 2TeV at LHC. This suppression is sufficient to be observed in the first year of low-luminosity running. Our prediction is based on the universal behavior of string theory, and therefore is qualitatively model-independent. This signature is alternative and complementary to conventional ones such as Regge resonance (or string ball/black hole) production. |
hep-ph/0510185 | Yuya Wakabayashi | Hidekazu Tanaka (Rikkyo University), Tetsuya Sugiura (Waseda High
School), Yuya Wakabayashi (Rikkyo University) | Factorization Algorithm for Parton Showers beyond the Leading
Logarithmic Order of QCD | 9 pages, PTPTeX.sty, 4 Postscript eps figures | Prog.Theor.Phys.114:477,2005 | 10.1143/PTP.114.477 | RUP-05-2 | hep-ph | null | A factorization algorithm for a patron shower model based on the evolution of
momentum distributions proposed in a previous work is studied. The scaling
violation of initial state parton distributions is generated using parton
showers to an accuracy of the next-to-leading logarithmic (NLL) order of
quantum chromodynamics (QCD) using the information from only splitting
functions and initial parton distributions at some fixed low energy. In the
algorithm proposed in this paper, the total momentum of the initial state
partons is conserved in any factorization scheme for mass singularities. As an
example, the scaling violation of the parton distributions and the transverse
momentum distributions due to initial state parton radiation are calculated
with the jet calculs scheme.
| [
{
"created": "Fri, 14 Oct 2005 07:28:16 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Tanaka",
"Hidekazu",
"",
"Rikkyo University"
],
[
"Sugiura",
"Tetsuya",
"",
"Waseda High\n School"
],
[
"Wakabayashi",
"Yuya",
"",
"Rikkyo University"
]
] | A factorization algorithm for a patron shower model based on the evolution of momentum distributions proposed in a previous work is studied. The scaling violation of initial state parton distributions is generated using parton showers to an accuracy of the next-to-leading logarithmic (NLL) order of quantum chromodynamics (QCD) using the information from only splitting functions and initial parton distributions at some fixed low energy. In the algorithm proposed in this paper, the total momentum of the initial state partons is conserved in any factorization scheme for mass singularities. As an example, the scaling violation of the parton distributions and the transverse momentum distributions due to initial state parton radiation are calculated with the jet calculs scheme. |
2104.04399 | Oliver Gould | Oliver Gould and Tuomas V. I. Tenkanen | On the perturbative expansion at high temperature and implications for
cosmological phase transitions | 36 pages, 7 figures | JHEP 06 (2021) 069 | 10.1007/JHEP06(2021)069 | NORDITA 2021-010 | hep-ph astro-ph.CO gr-qc hep-th | http://creativecommons.org/licenses/by/4.0/ | We revisit the perturbative expansion at high temperature and investigate its
convergence by inspecting the renormalisation scale dependence of the effective
potential. Although at zero temperature the renormalisation group improved
effective potential is scale independent at one-loop, we show how this breaks
down at high temperature, due to the misalignment of loop and coupling
expansions. Following this, we show how one can recover renormalisation scale
independence at high temperature, and that it requires computations at two-loop
order. We demonstrate how this resolves some of the huge theoretical
uncertainties in the gravitational wave signal of first-order phase
transitions, though uncertainties remain stemming from the computation of the
bubble nucleation rate.
| [
{
"created": "Fri, 9 Apr 2021 14:36:06 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Jun 2021 19:08:23 GMT",
"version": "v2"
}
] | 2021-06-24 | [
[
"Gould",
"Oliver",
""
],
[
"Tenkanen",
"Tuomas V. I.",
""
]
] | We revisit the perturbative expansion at high temperature and investigate its convergence by inspecting the renormalisation scale dependence of the effective potential. Although at zero temperature the renormalisation group improved effective potential is scale independent at one-loop, we show how this breaks down at high temperature, due to the misalignment of loop and coupling expansions. Following this, we show how one can recover renormalisation scale independence at high temperature, and that it requires computations at two-loop order. We demonstrate how this resolves some of the huge theoretical uncertainties in the gravitational wave signal of first-order phase transitions, though uncertainties remain stemming from the computation of the bubble nucleation rate. |
1309.7772 | Marek Tasevsky | Marek Tasevsky | Exclusive MSSM Higgs production at the LHC after Run I | 21 pages, 10 figures. Changes reflecting the review process in
submission to EPJC: minor textual improvements, plots 1-6 with a more
appropriate range on y-axis, added references | Eur.Phys.J. C73 (2013) 2672 | 10.1140/epjc/s10052-013-2672-7 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the prospects for Central Exclusive Production (CEP) of MSSM
Higgs bosons at the LHC using forward proton detectors proposed to be installed
at 220 m and 420 m distance around ATLAS and / or CMS. We summarize the
situation after the first and very successful data taking period of the LHC.
The discovery of a Higgs boson and results from searches for additional MSSM
Higgs bosons from both the ATLAS and CMS experiments, based on data samples
each corresponding to about 25 fb-1, have recently led to a proposal of new
low-energy MSSM benchmark scenarios. The CEP signal cross section for the
process H/h -> bb and its backgrounds are estimated in these new scenarios. We
also make some comments about the experimental procedure if the proposed
forward proton detectors are to be used to measure the CEP signal.
| [
{
"created": "Mon, 30 Sep 2013 09:37:18 GMT",
"version": "v1"
},
{
"created": "Sat, 30 Nov 2013 10:46:37 GMT",
"version": "v2"
}
] | 2014-01-21 | [
[
"Tasevsky",
"Marek",
""
]
] | We investigate the prospects for Central Exclusive Production (CEP) of MSSM Higgs bosons at the LHC using forward proton detectors proposed to be installed at 220 m and 420 m distance around ATLAS and / or CMS. We summarize the situation after the first and very successful data taking period of the LHC. The discovery of a Higgs boson and results from searches for additional MSSM Higgs bosons from both the ATLAS and CMS experiments, based on data samples each corresponding to about 25 fb-1, have recently led to a proposal of new low-energy MSSM benchmark scenarios. The CEP signal cross section for the process H/h -> bb and its backgrounds are estimated in these new scenarios. We also make some comments about the experimental procedure if the proposed forward proton detectors are to be used to measure the CEP signal. |
2308.10035 | Yi-Lun Du | Yi-Lun Du | Overview: Jet quenching with machine learning | 11 pages, 11th International Conference on Hard and Electromagnetic
Probes of High-Energy Nuclear Collisions (Hard Probes 2023) | null | null | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Jets are suppressed and modified in heavy ion collisions, which serve as
powerful probes to the properties of the quark-gluon plasma (QGP). Attributed
to the abundant information carried by the jet constituents and reconstructed
substructures, plenty of interesting applications of machine learning
techniques have been made on a jet-by-jet basis to study the jet quenching
phenomena. Here we review recent proceedings on this topic including the tasks
of reconstructing jet momentum in heavy ion collisions, classifying quenched
jets and unquenched jets, identifying jet energy loss, locating the jet
creation points as well as distinguishing between quark- and gluon-initiated
jets in the QGP. Such jet-by-jet analyses will allow us to have a better handle
on the jet reconstruction and selections to investigate the effects of jet
modifications and push forward the long-standing goal of jet tomographic probes
of the QGP.
| [
{
"created": "Sat, 19 Aug 2023 14:43:54 GMT",
"version": "v1"
}
] | 2023-08-22 | [
[
"Du",
"Yi-Lun",
""
]
] | Jets are suppressed and modified in heavy ion collisions, which serve as powerful probes to the properties of the quark-gluon plasma (QGP). Attributed to the abundant information carried by the jet constituents and reconstructed substructures, plenty of interesting applications of machine learning techniques have been made on a jet-by-jet basis to study the jet quenching phenomena. Here we review recent proceedings on this topic including the tasks of reconstructing jet momentum in heavy ion collisions, classifying quenched jets and unquenched jets, identifying jet energy loss, locating the jet creation points as well as distinguishing between quark- and gluon-initiated jets in the QGP. Such jet-by-jet analyses will allow us to have a better handle on the jet reconstruction and selections to investigate the effects of jet modifications and push forward the long-standing goal of jet tomographic probes of the QGP. |
0706.2192 | Peter A. Sturrock | P.A. Sturrock and M.S. Wheatland | Analysis and packaging of radiochemical solar neutrino data. 1. Bayesian
approach | 8 pages | SolarPhys.247:217-224,2008 | 10.1007/s11207-007-9112-5 | null | hep-ph astro-ph gr-qc | null | According to current practice, the results of each run of a radiochemical
solar neutrino experiment comprise an estimate of the flux and upper and lower
error estimates. These estimates are derived by a maximum-likelihood procedure
from the times of decay events in the analysis chamber. This procedure has the
following shortcomings: (a) Published results sometimes include negative flux
estimates. (b) Even if the flux estimate is non-negative, the probability
distribution function implied by the flux and error estimates will extend into
negative territory; and (c) The overall flux estimate derived from the results
of a sequence of runs may differ substantially from an estimate made by a
global analysis of all of the timing data taken together. These defects
indicate that the usual packaging of data in radiochemical solar neutrino
experiments provides an inadequate summary of the data, which implies a loss of
information. This article reviews this problem from a Bayesian perspective, and
suggests an alternative scheme for the packaging of radiochemical solar
neutrino data, which is we believe free from the above objections.
| [
{
"created": "Thu, 14 Jun 2007 20:28:26 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Oct 2007 18:19:11 GMT",
"version": "v2"
}
] | 2008-12-18 | [
[
"Sturrock",
"P. A.",
""
],
[
"Wheatland",
"M. S.",
""
]
] | According to current practice, the results of each run of a radiochemical solar neutrino experiment comprise an estimate of the flux and upper and lower error estimates. These estimates are derived by a maximum-likelihood procedure from the times of decay events in the analysis chamber. This procedure has the following shortcomings: (a) Published results sometimes include negative flux estimates. (b) Even if the flux estimate is non-negative, the probability distribution function implied by the flux and error estimates will extend into negative territory; and (c) The overall flux estimate derived from the results of a sequence of runs may differ substantially from an estimate made by a global analysis of all of the timing data taken together. These defects indicate that the usual packaging of data in radiochemical solar neutrino experiments provides an inadequate summary of the data, which implies a loss of information. This article reviews this problem from a Bayesian perspective, and suggests an alternative scheme for the packaging of radiochemical solar neutrino data, which is we believe free from the above objections. |
hep-ph/9411286 | null | F. Buccella, M. Lusignoli, G. Miele, A. Pugliese and P. Santorelli | Nonleptonic weak decays of charmed mesons | 24 pages, plain TeX, uses harvmac.tex and tables.tex | Phys.Rev.D51:3478-3486,1995 | 10.1103/PhysRevD.51.3478 | ROMA Preprint n. 1070-1994, NAPOLI DSF-T-56/94 | hep-ph | null | A previous analysis of two-body Cabibbo allowed nonleptonic decays of $D^0$
mesons and of Cabibbo allowed and first-forbidden decays of $D^+$ and $D_s^+$
has been adjourned using more recent experimental data and extended to the
Cabibbo forbidden decays of $D^0$. Annihilation and W-exchange contributions as
well as final state interaction effects (assumed to be dominated by nearby
resonances) have been included and are in fact crucial to obtain a reasonable
agreement with the experimental data, which show large flavour SU(3)
violations. New fitting parameters are necessary to describe rescattering
effects for Cabibbo forbidden $D^0$ decays, given the lack of experimental
informations on isoscalar resonances. We keep their number to a minimum - three
- using phenomenologically based considerations. We also discuss CP violating
asymmetries.
| [
{
"created": "Mon, 14 Nov 1994 10:50:57 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Buccella",
"F.",
""
],
[
"Lusignoli",
"M.",
""
],
[
"Miele",
"G.",
""
],
[
"Pugliese",
"A.",
""
],
[
"Santorelli",
"P.",
""
]
] | A previous analysis of two-body Cabibbo allowed nonleptonic decays of $D^0$ mesons and of Cabibbo allowed and first-forbidden decays of $D^+$ and $D_s^+$ has been adjourned using more recent experimental data and extended to the Cabibbo forbidden decays of $D^0$. Annihilation and W-exchange contributions as well as final state interaction effects (assumed to be dominated by nearby resonances) have been included and are in fact crucial to obtain a reasonable agreement with the experimental data, which show large flavour SU(3) violations. New fitting parameters are necessary to describe rescattering effects for Cabibbo forbidden $D^0$ decays, given the lack of experimental informations on isoscalar resonances. We keep their number to a minimum - three - using phenomenologically based considerations. We also discuss CP violating asymmetries. |
1203.1100 | Jonathan Cornell | Jonathan M. Cornell and Stefano Profumo | Earthly probes of the smallest dark matter halos | 26 pages, 6 figures, to appear in JCAP | JCAP06(2012)011 | 10.1088/1475-7516/2012/06/011 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dark matter kinetic decoupling involves elastic scattering of dark matter off
of leptons and quarks in the early universe, the same process relevant for
direct detection and for the capture rate of dark matter in celestial bodies;
the resulting size of the smallest dark matter collapsed structures should thus
correlate with quantities connected with direct detection rates and with the
flux of high-energy neutrinos from dark matter annihilation in the Sun or in
the Earth. In this paper we address this general question in the context of two
widely studied and paradigmatic weakly-interacting particle dark matter models:
the lightest neutralino of the minimal supersymmetric extension of the Standard
Model, and the lightest Kaluza-Klein particle of Universal Extra Dimensions
(UED). We argue and show that while the scalar neutralino-nucleon cross section
correlates poorly with the kinetic decoupling temperature, the spin-dependent
cross section exhibits a strong correlation in a wide range of models. In UED
models the correlation is present for both cross sections, and is
extraordinarily tight for the spin-dependent case. A strong correlation is also
found, for both models, for the flux of neutrinos from the Sun, especially for
fluxes large enough to be at potentially detectable levels. We provide analytic
guidance and formulae that illustrate our findings.
| [
{
"created": "Tue, 6 Mar 2012 05:23:43 GMT",
"version": "v1"
},
{
"created": "Mon, 14 May 2012 23:23:19 GMT",
"version": "v2"
}
] | 2012-06-12 | [
[
"Cornell",
"Jonathan M.",
""
],
[
"Profumo",
"Stefano",
""
]
] | Dark matter kinetic decoupling involves elastic scattering of dark matter off of leptons and quarks in the early universe, the same process relevant for direct detection and for the capture rate of dark matter in celestial bodies; the resulting size of the smallest dark matter collapsed structures should thus correlate with quantities connected with direct detection rates and with the flux of high-energy neutrinos from dark matter annihilation in the Sun or in the Earth. In this paper we address this general question in the context of two widely studied and paradigmatic weakly-interacting particle dark matter models: the lightest neutralino of the minimal supersymmetric extension of the Standard Model, and the lightest Kaluza-Klein particle of Universal Extra Dimensions (UED). We argue and show that while the scalar neutralino-nucleon cross section correlates poorly with the kinetic decoupling temperature, the spin-dependent cross section exhibits a strong correlation in a wide range of models. In UED models the correlation is present for both cross sections, and is extraordinarily tight for the spin-dependent case. A strong correlation is also found, for both models, for the flux of neutrinos from the Sun, especially for fluxes large enough to be at potentially detectable levels. We provide analytic guidance and formulae that illustrate our findings. |
1402.3703 | Anatoly Kotikov Vassilievich | A.V. Kotikov, B.G. Shaikhatdenov | Q^2-evolution of parton densities at small x values and H1 and ZEUS
experimental data | 9 pages, 4 figures, talk given at II Russian-Spanish Congress
"Particle and Nuclear Physics at all scales, Astroparticle Physics and
Cosmology", Saint-Petersburg, October 1-4, 2013 | null | 10.1063/1.4891128 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that in the leading twist approximation of the Wilson operator
product expansion with "frozen" and analytic strong coupling constants,
considering the Bessel-inspired behavior of the structure functions F2 and the
derivative d ln F2/(d ln(1/x)) at small x values, obtained for a flat initial
condition in the DGLAP evolution equations,leads to a good agreement with the
deep inelastic scattering H1 and ZEUS experimental data from HERA
| [
{
"created": "Sat, 15 Feb 2014 16:35:07 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Kotikov",
"A. V.",
""
],
[
"Shaikhatdenov",
"B. G.",
""
]
] | It is shown that in the leading twist approximation of the Wilson operator product expansion with "frozen" and analytic strong coupling constants, considering the Bessel-inspired behavior of the structure functions F2 and the derivative d ln F2/(d ln(1/x)) at small x values, obtained for a flat initial condition in the DGLAP evolution equations,leads to a good agreement with the deep inelastic scattering H1 and ZEUS experimental data from HERA |
hep-ph/9411416 | Sang Jin Sin | Hyun Kyu Lee, Mannque Rho and Sang-Jin Sin | Renormalization-Group Flow Analysis of Meson Condensations in Dense
Matter | 12 pages, 2 figures, (latex 36k+90k) | Phys.Lett. B348 (1995) 290-296 | 10.1016/0370-2693(95)00171-G | null | hep-ph nucl-th | null | We present a renormalization-group (RG) flow argument for s-wave kaon
condensation in dense nuclear-star matter predicted in chiral perturbation
theory. It is shown that it is the {\it relevant} mass term together with {\it
any} attractive interaction for the kaon in medium that triggers the
instability. We show that a saddle point of multi-dimensional RG flow can imply
a phase transition. Pion condensation is also analyzed along the same line of
reasoning.
| [
{
"created": "Tue, 29 Nov 1994 15:05:57 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Lee",
"Hyun Kyu",
""
],
[
"Rho",
"Mannque",
""
],
[
"Sin",
"Sang-Jin",
""
]
] | We present a renormalization-group (RG) flow argument for s-wave kaon condensation in dense nuclear-star matter predicted in chiral perturbation theory. It is shown that it is the {\it relevant} mass term together with {\it any} attractive interaction for the kaon in medium that triggers the instability. We show that a saddle point of multi-dimensional RG flow can imply a phase transition. Pion condensation is also analyzed along the same line of reasoning. |
1308.1062 | Anna Stasto | Christian A. Cruz-Santiago and Anna M. Stasto | Recursion relations and scattering amplitudes in the light-front
formalism | 15 pages, 5 figures, LaTeX | null | 10.1016/j.nuclphysb.2013.07.019 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The fragmentation functions and scattering amplitudes are investigated in the
framework of light-front perturbation theory. It is demonstrated that, the
factorization property of the fragmentation functions implies the recursion
relations for the off-shell scattering amplitudes which are light-front analogs
of the Berends-Giele relations. These recursion relations on the light-front
can be solved exactly by induction and it is shown that the expressions for the
off-shell light-front amplitudes are represented as a linear combinations of
the on-shell amplitudes. By putting external particles on-shell we recover the
scattering amplitudes previously derived in the literature.
| [
{
"created": "Mon, 5 Aug 2013 18:38:15 GMT",
"version": "v1"
}
] | 2015-06-16 | [
[
"Cruz-Santiago",
"Christian A.",
""
],
[
"Stasto",
"Anna M.",
""
]
] | The fragmentation functions and scattering amplitudes are investigated in the framework of light-front perturbation theory. It is demonstrated that, the factorization property of the fragmentation functions implies the recursion relations for the off-shell scattering amplitudes which are light-front analogs of the Berends-Giele relations. These recursion relations on the light-front can be solved exactly by induction and it is shown that the expressions for the off-shell light-front amplitudes are represented as a linear combinations of the on-shell amplitudes. By putting external particles on-shell we recover the scattering amplitudes previously derived in the literature. |
1503.04825 | Julia Harz | Frank F. Deppisch, Julia Harz, Martin Hirsch, Wei-Chih Huang and
Heinrich P\"as | Falsifying High-Scale Baryogenesis with Neutrinoless Double Beta Decay
and Lepton Flavor Violation | 5 pages, 2 figures; minor additions, matches published version | Phys. Rev. D 92, 036005 (2015) | 10.1103/PhysRevD.92.036005 | LCTS/2015-05 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Interactions that manifest themselves as lepton number violating processes at
low energies in combination with sphaleron transitions typically erase any
preexisting baryon asymmetry of the Universe. In this article, we discuss the
constraints obtained from an observation of neutrinoless double beta decay in
this context. If a new physics mechanism of neutrinoless double beta decay
other than the standard light neutrino exchange is observed, typical scenarios
of high-scale baryogenesis will be excluded unless the baryon asymmetry is
stabilized via some new mechanism. We also sketch how this conclusion can be
extended beyond the first lepton generation by incorporating lepton flavor
violating processes.
| [
{
"created": "Mon, 16 Mar 2015 20:04:08 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Sep 2015 18:12:31 GMT",
"version": "v2"
}
] | 2015-09-14 | [
[
"Deppisch",
"Frank F.",
""
],
[
"Harz",
"Julia",
""
],
[
"Hirsch",
"Martin",
""
],
[
"Huang",
"Wei-Chih",
""
],
[
"Päs",
"Heinrich",
""
]
] | Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any preexisting baryon asymmetry of the Universe. In this article, we discuss the constraints obtained from an observation of neutrinoless double beta decay in this context. If a new physics mechanism of neutrinoless double beta decay other than the standard light neutrino exchange is observed, typical scenarios of high-scale baryogenesis will be excluded unless the baryon asymmetry is stabilized via some new mechanism. We also sketch how this conclusion can be extended beyond the first lepton generation by incorporating lepton flavor violating processes. |
hep-ph/9610398 | Max Klein | M. Klein | Deep Inelastic Physics with H1 | 20 pages incl. 11 ps figures, Proc. 4th Int.Conf. on Deep Inelastic
Scattering, Rome 1996 | null | null | DESY 96-218 | hep-ph | null | A summary is presented of deep inelastic physics results obtained by the H1
collaboration during its first three years of experimentation at the
electron-proton collider HERA.
| [
{
"created": "Thu, 17 Oct 1996 21:14:24 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Klein",
"M.",
""
]
] | A summary is presented of deep inelastic physics results obtained by the H1 collaboration during its first three years of experimentation at the electron-proton collider HERA. |
hep-ph/0503069 | Christopher D. Carone | Christopher D. Carone (William and Mary) | Tri-N-ification | 21 pages LaTeX, 6 eps figures | Phys.Rev. D71 (2005) 075013 | 10.1103/PhysRevD.71.075013 | WM-05-106 | hep-ph | null | We consider a natural generalization of trinification to theories with 3N
SU(3) gauge groups. These theories have a simple moose representation and a
gauge boson spectrum that can be interpreted via the deconstruction of a 5D
theory with unified symmetry broken on a boundary. Although the matter and
Higgs sectors of the theory have no simple extra-dimensional analog, gauge
unification retains features characteristic of the 5D theory. We determine
possible assignments of the matter and Higgs fields to unified multiplets and
present theories that are viable alternatives to minimal trinified GUTs.
| [
{
"created": "Mon, 7 Mar 2005 21:00:04 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Carone",
"Christopher D.",
"",
"William and Mary"
]
] | We consider a natural generalization of trinification to theories with 3N SU(3) gauge groups. These theories have a simple moose representation and a gauge boson spectrum that can be interpreted via the deconstruction of a 5D theory with unified symmetry broken on a boundary. Although the matter and Higgs sectors of the theory have no simple extra-dimensional analog, gauge unification retains features characteristic of the 5D theory. We determine possible assignments of the matter and Higgs fields to unified multiplets and present theories that are viable alternatives to minimal trinified GUTs. |
hep-ph/0512177 | M Vepsalainen | A. Gynther, M. Vepsalainen | Pressure of the Standard Model Near the Electroweak Phase Transition | 16 pages, 6 figures. v2: published version | JHEP 0603 (2006) 011 | 10.1088/1126-6708/2006/03/011 | HIP-2005-55/TH | hep-ph | null | We extend our previous determination of the thermodynamic pressure of the
Standard Model so that the result can be applied down to temperatures
corresponding to the electroweak crossover. This requires a further resummation
which can be cleanly organised within the effective theory framework. The
result allows for a precise determination of the expansion rate of the Universe
for temperatures around the electroweak crossover.
| [
{
"created": "Wed, 14 Dec 2005 09:46:01 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Mar 2006 10:05:42 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Gynther",
"A.",
""
],
[
"Vepsalainen",
"M.",
""
]
] | We extend our previous determination of the thermodynamic pressure of the Standard Model so that the result can be applied down to temperatures corresponding to the electroweak crossover. This requires a further resummation which can be cleanly organised within the effective theory framework. The result allows for a precise determination of the expansion rate of the Universe for temperatures around the electroweak crossover. |
2109.04195 | Ruben Flores | Ruben Flores-Mendieta, Carlos Isaac Garcia, Johann Hernandez, Maria
Anabel Trejo | Baryon magnetic moment in large-$N_c$ chiral perturbation theory:
Complete analysis for $N_c=3$ | 97 pages, 2 figures, 14 tables | null | 10.1103/PhysRevD.104.114024 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Baryon magnetic moments are computed in baryon chiral perturbation theory in
the large-$N_c$ limit at one-loop order, where $N_c$ is the number of color
charges. Orders $\mathcal{O}(m_q^{1/2})$ and $\mathcal{O}(m_q \ln m_q)$
corrections are both evaluated including all the operator structures that
participate at the physical value $N_c=3$. The complete expressions for octet
and decuplet baryon magnetic moments in addition to decuplet-octet baryon
transition moments are thus compared to their available counterparts obtained
in heavy baryon chiral perturbation theory for degenerate intermediate baryons
in the loops. Theoretical expressions fully agree at the physical values
$N_c=3$ and $N_f=3$ flavors of light quarks. Some numerical evaluations are
produced via a least-squares fit to explore the free parameters in the
analysis. Results point out the necessity of incorporating the effects of
non-degenerate intermediate baryons in the loops for a consistent determination
of these free parameters.
| [
{
"created": "Thu, 9 Sep 2021 12:00:05 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Dec 2021 15:24:38 GMT",
"version": "v2"
}
] | 2022-01-05 | [
[
"Flores-Mendieta",
"Ruben",
""
],
[
"Garcia",
"Carlos Isaac",
""
],
[
"Hernandez",
"Johann",
""
],
[
"Trejo",
"Maria Anabel",
""
]
] | Baryon magnetic moments are computed in baryon chiral perturbation theory in the large-$N_c$ limit at one-loop order, where $N_c$ is the number of color charges. Orders $\mathcal{O}(m_q^{1/2})$ and $\mathcal{O}(m_q \ln m_q)$ corrections are both evaluated including all the operator structures that participate at the physical value $N_c=3$. The complete expressions for octet and decuplet baryon magnetic moments in addition to decuplet-octet baryon transition moments are thus compared to their available counterparts obtained in heavy baryon chiral perturbation theory for degenerate intermediate baryons in the loops. Theoretical expressions fully agree at the physical values $N_c=3$ and $N_f=3$ flavors of light quarks. Some numerical evaluations are produced via a least-squares fit to explore the free parameters in the analysis. Results point out the necessity of incorporating the effects of non-degenerate intermediate baryons in the loops for a consistent determination of these free parameters. |
1409.3049 | Francesco Dighera | Martin Beneke, Francesco Dighera, Andrzej Hryczuk | Relic density computations at NLO: infrared finiteness and thermal
correction | 36 pages, 6 figures, 6 tables; v2: erratum added, substantial change
of the finite part of the thermal correction | null | null | TUM-HEP 1052/16 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There is an increasing interest in accurate dark matter relic density
predictions, which requires next-to-leading order (NLO) calculations. The
method applied up to now uses zero-temperature NLO calculations of annihilation
cross sections in the standard Boltzmann equation for freeze-out, and is
conceptually problematic, since it ignores the finite-temperature infrared (IR)
divergences from soft and collinear radiation and virtual effects. We address
this problem systematically by starting from non-equilibrium quantum field
theory, and demonstrate on a realistic model that soft and collinear
temperature-dependent divergences cancel in the collision term. Our analysis
provides justification for the use of the freeze-out equation in its
conventional form and determines the leading finite-temperature correction to
the annihilation cross section. This turns out to have a remarkably simple
structure.
| [
{
"created": "Wed, 10 Sep 2014 12:59:04 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Jul 2016 20:11:41 GMT",
"version": "v2"
}
] | 2016-07-15 | [
[
"Beneke",
"Martin",
""
],
[
"Dighera",
"Francesco",
""
],
[
"Hryczuk",
"Andrzej",
""
]
] | There is an increasing interest in accurate dark matter relic density predictions, which requires next-to-leading order (NLO) calculations. The method applied up to now uses zero-temperature NLO calculations of annihilation cross sections in the standard Boltzmann equation for freeze-out, and is conceptually problematic, since it ignores the finite-temperature infrared (IR) divergences from soft and collinear radiation and virtual effects. We address this problem systematically by starting from non-equilibrium quantum field theory, and demonstrate on a realistic model that soft and collinear temperature-dependent divergences cancel in the collision term. Our analysis provides justification for the use of the freeze-out equation in its conventional form and determines the leading finite-temperature correction to the annihilation cross section. This turns out to have a remarkably simple structure. |
hep-ph/9706244 | Akaki Rusetsky | V. E. Lyubovitskij (JINR, Dubna and Tomsk University), E. Z. Lipartia
(JINR, Dubna and Tbilisi University), A. G. Rusetsky (JINR, Dubna and Tbilisi
University) | Perturbative framework for the study of the properties of the pi(+)pi(-)
atom | 11 pages, LaTeX-file (elsart.sty) | null | null | QFT-TSU/97-50 | hep-ph | null | The perturbative framework is developed for the calculation of the pi(+)pi(-)
atom characteristics (energy level shift and lifetime) on the basis of the
field-theoretical Bethe-Salpeter approach. A closed expression for the
first-order correction to the pi(+)pi(-) atom lifetime has been obtained.
| [
{
"created": "Wed, 4 Jun 1997 09:01:37 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Lyubovitskij",
"V. E.",
"",
"JINR, Dubna and Tomsk University"
],
[
"Lipartia",
"E. Z.",
"",
"JINR, Dubna and Tbilisi University"
],
[
"Rusetsky",
"A. G.",
"",
"JINR, Dubna and Tbilisi\n University"
]
] | The perturbative framework is developed for the calculation of the pi(+)pi(-) atom characteristics (energy level shift and lifetime) on the basis of the field-theoretical Bethe-Salpeter approach. A closed expression for the first-order correction to the pi(+)pi(-) atom lifetime has been obtained. |
hep-ph/0610268 | Andrej Arbuzov | A. Andonov, A. Arbuzov, S. Bondarenko, P. Christova, V. Kolesnikov, R.
Sadykov | QCD branch in SANC | 15 pages, 5 figures (eps) | null | null | null | hep-ph | null | The QCD sector of the system SANC is presented. QCD theoretical predictions
for several processes of high energy interactions of fundamental particles at
the one-loop precision level for up to some 3- and 4-particle processes are
implemented.
| [
{
"created": "Fri, 20 Oct 2006 12:26:59 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Jun 2007 07:11:34 GMT",
"version": "v2"
}
] | 2007-06-27 | [
[
"Andonov",
"A.",
""
],
[
"Arbuzov",
"A.",
""
],
[
"Bondarenko",
"S.",
""
],
[
"Christova",
"P.",
""
],
[
"Kolesnikov",
"V.",
""
],
[
"Sadykov",
"R.",
""
]
] | The QCD sector of the system SANC is presented. QCD theoretical predictions for several processes of high energy interactions of fundamental particles at the one-loop precision level for up to some 3- and 4-particle processes are implemented. |
hep-ph/9906249 | null | V.E. Markushin and M.P. Locher (Paul Scherrer Institute, Switzerland) | Structure of the Light Scalar Mesons from a Coupled Channel Analysis of
the s-wave pi pi - k kbar Scattering | 8 pages, 6 PostScript figures, Contribution to the Workshop on Hadron
Spectroscopy, Frascati, March 8-12, 1999 | FrascatiPhys.Ser.15:229-236,1999 | null | PSI-PR-99-15 | hep-ph | null | The analysis of the poles of the $\pi\pi$ scattering amplitude is shown to
favour a dynamical origin of the sigma meson: it is created by a strongly
attractive $\pi\pi$ interaction in the $J^{PC}=0^{++}I=0$ channel. In the limit
$N_c\to\infty$, the $\sigma$ meson disappears, contrary to the case of
conventional $q\bar{q}$ states. Implications for the search of the scalar
$q\bar{q}$ and glueball states are discussed.
| [
{
"created": "Fri, 4 Jun 1999 10:59:08 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Markushin",
"V. E.",
"",
"Paul Scherrer Institute, Switzerland"
],
[
"Locher",
"M. P.",
"",
"Paul Scherrer Institute, Switzerland"
]
] | The analysis of the poles of the $\pi\pi$ scattering amplitude is shown to favour a dynamical origin of the sigma meson: it is created by a strongly attractive $\pi\pi$ interaction in the $J^{PC}=0^{++}I=0$ channel. In the limit $N_c\to\infty$, the $\sigma$ meson disappears, contrary to the case of conventional $q\bar{q}$ states. Implications for the search of the scalar $q\bar{q}$ and glueball states are discussed. |
1609.04236 | Debasish Borah | Debasish Borah and Arnab Dasgupta | Observable Lepton Number Violation with Predominantly Dirac Nature of
Active Neutrinos | 33 pages, 16 figures, to appear in JHEP | null | 10.1007/JHEP01(2017)072 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study a specific version of $SU(2)_R \times SU(2)_L \times U(1)_{B-L}$
models extended by discrete symmetries where the new physics sector responsible
for tiny neutrino masses at leading order remains decoupled from the new
physics sector that can give rise to observable signatures of lepton number
violation such as neutrinoless double beta decay. More specifically, the
dominant contribution to light neutrino masses comes from a one-loop Dirac
mass. At higher loop level, a tiny Majorana mass also appears which remains
suppressed by many order of magnitudes in comparison to the Dirac mass. Such a
model where the active neutrinos are predominantly of Dirac type, also predicts
observable charged lepton flavour violation like $\mu \rightarrow 3e, \mu
\rightarrow e \gamma$ and multi-component dark matter.
| [
{
"created": "Wed, 14 Sep 2016 12:25:39 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Jan 2017 12:00:50 GMT",
"version": "v2"
}
] | 2017-03-08 | [
[
"Borah",
"Debasish",
""
],
[
"Dasgupta",
"Arnab",
""
]
] | We study a specific version of $SU(2)_R \times SU(2)_L \times U(1)_{B-L}$ models extended by discrete symmetries where the new physics sector responsible for tiny neutrino masses at leading order remains decoupled from the new physics sector that can give rise to observable signatures of lepton number violation such as neutrinoless double beta decay. More specifically, the dominant contribution to light neutrino masses comes from a one-loop Dirac mass. At higher loop level, a tiny Majorana mass also appears which remains suppressed by many order of magnitudes in comparison to the Dirac mass. Such a model where the active neutrinos are predominantly of Dirac type, also predicts observable charged lepton flavour violation like $\mu \rightarrow 3e, \mu \rightarrow e \gamma$ and multi-component dark matter. |
1703.00246 | Vahid Reza Shajiee | Ali Tofighi, Vahid Reza Shajiee | Mass of the Stabilized Radion in the Limit of Finite Quartic Coupling | 11 pages, 3 figures, Accepted for publication in AHEP | Adv.High Energy Phys. 2017 (2017) 1213670 | 10.1155/2017/1213670 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an exact treatment of the modulus stabilization condition with the
general boundary conditions of the bulk scalar field in the Randall-Sundrum
model. We find analytical expressions for the value of the modulus and the mass
of the radion.
| [
{
"created": "Wed, 1 Mar 2017 11:41:38 GMT",
"version": "v1"
}
] | 2019-02-04 | [
[
"Tofighi",
"Ali",
""
],
[
"Shajiee",
"Vahid Reza",
""
]
] | We present an exact treatment of the modulus stabilization condition with the general boundary conditions of the bulk scalar field in the Randall-Sundrum model. We find analytical expressions for the value of the modulus and the mass of the radion. |
hep-ph/9505429 | Renard Fernand Michel | G.J. Gounaris, F.M. Renard | Anomalous Couplings in Single Higgs Production through $\gamma\gamma$
Collisions | 8 pages + 13 figures in ps file. | Z.Phys. C69 (1996) 513-518 | null | PM/95-20, THES-TP 95/07 | hep-ph | null | We show that single Higgs production in $\gamma\gamma$ collisions through
laser backscattering provides the best way to look for New Physics (NP) effects
inducing anomalous Higgs couplings. Our analysis is based on the four $dim=6$
operators $\O_{UB}$, $\O_{UW}$, $\ol{\O}_{UB}$ and $\ol{\O}_{UW}$ which
describe New Physics effects in this sector. Using the Higgs production rate we
establish observability limits for the couplings of the aforementioned
operators at a level of $10^{-3}$, which means establishing lower bounds on the
scale of NP of the order 30 to 200 TeV. Higgs branching ratios, especially the
ratio $\Gamma(H\to\gamma\gamma)/\Gamma (H\to\gamma Z)$, are shown to provide
powerful ways to disentangle the effects of the various operators.
| [
{
"created": "Wed, 31 May 1995 08:13:17 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Gounaris",
"G. J.",
""
],
[
"Renard",
"F. M.",
""
]
] | We show that single Higgs production in $\gamma\gamma$ collisions through laser backscattering provides the best way to look for New Physics (NP) effects inducing anomalous Higgs couplings. Our analysis is based on the four $dim=6$ operators $\O_{UB}$, $\O_{UW}$, $\ol{\O}_{UB}$ and $\ol{\O}_{UW}$ which describe New Physics effects in this sector. Using the Higgs production rate we establish observability limits for the couplings of the aforementioned operators at a level of $10^{-3}$, which means establishing lower bounds on the scale of NP of the order 30 to 200 TeV. Higgs branching ratios, especially the ratio $\Gamma(H\to\gamma\gamma)/\Gamma (H\to\gamma Z)$, are shown to provide powerful ways to disentangle the effects of the various operators. |
hep-ph/9406331 | Mary Hall Reno | Kevin R. Barger and M. H. Reno | Hadron collider limits on anomalous $WW\gamma$ couplings | Revtex 23 pages + 8 figures, UIOWA-94-10 | Phys.Rev. D51 (1995) 90-98 | 10.1103/PhysRevD.51.90 | null | hep-ph | null | A next-to-leading log calculation of the reactions $pp$ and
$p\overline{p}\rightarrow W^\pm\gamma X$ is presented including a tri-boson
gauge coupling from non-Standard Model contributions. Two approaches are made
for comparison. The first approach considers the tri-boson $WW\gamma$ coupling
as being uniquely fixed by tree level unitarity at high energies to its
Standard Model form and, consequently, suppresses the non-Standard Model
contributions with form factors. The second approach is to ignore such
considerations and calculate the contributions to non-Standard Model tri-boson
gauge couplings without such suppressions. It is found that at Tevatron
energies, the two approaches do not differ much in quantitative results, while
at Large Hadron Collider (LHC) energies the two approaches give significantly
different predictions for production rates. At the Tevatron and LHC, however,
the sensitivity limits on the anomalous coupling of $WW\gamma$ are too weak to
usefully constrain parameters in effective Lagrangian models.
| [
{
"created": "Thu, 16 Jun 1994 16:19:06 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Barger",
"Kevin R.",
""
],
[
"Reno",
"M. H.",
""
]
] | A next-to-leading log calculation of the reactions $pp$ and $p\overline{p}\rightarrow W^\pm\gamma X$ is presented including a tri-boson gauge coupling from non-Standard Model contributions. Two approaches are made for comparison. The first approach considers the tri-boson $WW\gamma$ coupling as being uniquely fixed by tree level unitarity at high energies to its Standard Model form and, consequently, suppresses the non-Standard Model contributions with form factors. The second approach is to ignore such considerations and calculate the contributions to non-Standard Model tri-boson gauge couplings without such suppressions. It is found that at Tevatron energies, the two approaches do not differ much in quantitative results, while at Large Hadron Collider (LHC) energies the two approaches give significantly different predictions for production rates. At the Tevatron and LHC, however, the sensitivity limits on the anomalous coupling of $WW\gamma$ are too weak to usefully constrain parameters in effective Lagrangian models. |
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