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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2202.08809 | George Rupp | Eef van Beveren and George Rupp | Comment on "Scrutinizing pion-pion scattering in light of recent lattice
phase shifts" | 1 page, 1 figure. v3: Considerably expanded, with an additional
figure and several extra references; version accepted for publication in
Phys. Rev. D as a Comment. v4: confusing typo corrected in final paragraph,
viz. "chiral-symmetry constraints" should read "crossing-symmetry
constraints" | Phys. Rev. D 107 (2023) 058501 | 10.1103/PhysRevD.107.058501 | null | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a recent paper by Xiu-Li Gao, Zhi-Hui Guo, Zhiguang Xiao, and Zhi-Yong
Zhou, Phys. Rev. D 105, 094002 (2022), here referred to as I, $S$-wave $\pi\pi$
scattering phase shifts obtained in a lattice-QCD calculation are analyzed
using dispersive $S$-matrix methods. We question the reliability of the
conclusion from this analysis that, for a pion mass of 391 MeV, the lattice
phases favor the presence of both a $\sigma$-meson bound state and a nearby
virtual state. Our main criticism concerns the neglect of the $S$-wave
$K\bar{K}$ channel, which was considered alongside additional $s\bar{s}$
interpolating fields in the lattice computation used by the authors of I and
also in typical coupled-channel models. As an illustration, some results from
such a recent model are presented as well. Concluding remarks concern possible
improvements of the analysis in I as well as further model tests.
| [
{
"created": "Thu, 17 Feb 2022 18:23:50 GMT",
"version": "v1"
},
{
"created": "Fri, 18 Feb 2022 02:54:04 GMT",
"version": "v2"
},
{
"created": "Thu, 16 Feb 2023 15:00:37 GMT",
"version": "v3"
},
{
"created": "Sat, 25 Feb 2023 14:17:56 GMT",
"version": "v4"
}
] | 2023-03-10 | [
[
"van Beveren",
"Eef",
""
],
[
"Rupp",
"George",
""
]
] | In a recent paper by Xiu-Li Gao, Zhi-Hui Guo, Zhiguang Xiao, and Zhi-Yong Zhou, Phys. Rev. D 105, 094002 (2022), here referred to as I, $S$-wave $\pi\pi$ scattering phase shifts obtained in a lattice-QCD calculation are analyzed using dispersive $S$-matrix methods. We question the reliability of the conclusion from this analysis that, for a pion mass of 391 MeV, the lattice phases favor the presence of both a $\sigma$-meson bound state and a nearby virtual state. Our main criticism concerns the neglect of the $S$-wave $K\bar{K}$ channel, which was considered alongside additional $s\bar{s}$ interpolating fields in the lattice computation used by the authors of I and also in typical coupled-channel models. As an illustration, some results from such a recent model are presented as well. Concluding remarks concern possible improvements of the analysis in I as well as further model tests. |
0809.0303 | Torbjorn Sjostrand | Torbj\"orn Sj\"ostrand | PYTHIA 8 Status Report | 5 pages, to appear in the proceedings of the HERA and the LHC
workshop, 26--30 May 2008, CERN | null | null | LU TP 08-17, MCnet/08/09 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Pythia 8, the C++ rewrite of the commonly-used Pythia event generator, is now
available in a first full-fledged version 8.1. The older Pythia 6.4 generator
in Fortran 77 is still maintained, for now, but users are strongly recommended
to try out and move to the new version as soon as feasible.
| [
{
"created": "Mon, 1 Sep 2008 19:31:43 GMT",
"version": "v1"
}
] | 2008-09-02 | [
[
"Sjöstrand",
"Torbjörn",
""
]
] | Pythia 8, the C++ rewrite of the commonly-used Pythia event generator, is now available in a first full-fledged version 8.1. The older Pythia 6.4 generator in Fortran 77 is still maintained, for now, but users are strongly recommended to try out and move to the new version as soon as feasible. |
2203.07579 | Aiichi Iwazaki | Aiichi Iwazaki | Radiation Burst by Axion Star Collision with Star in the Andromeda
Galaxy | 7 pages, to be published in Physics Letters B | null | 10.1016/j.physletb.2022.137089 | Nisho-1-2022 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Axion is a promising candidate of dark matter in the universe. A fraction of
dark matter axion may forms axion star with radius $\sim 10^2$km. We show that
the axion star emits radiation burst by the collision with K and M types main
sequence star in the Andromeda Galaxy. The emission arises in the atmosphere of
the star, in which electrons coherently oscillate due to oscillating electric
field of the axion star. The electric field is produced under magnetic field
$B$ of the star. We estimate the flux density of the radiation $\sim 1.6\times
10^{-3}\mbox{Jy}
(10^{-12}M_{\odot}/M_a)^2(10^{-5}\mbox{eV}/m_a)^3(B/10^2\mbox{G})^2\sqrt{3\times10^3\mbox{K}/T}$
and the rate of the collision per hour $\sim
0.06/\mbox{hour}\,(10^{-12}M_{\odot}/M_a)$ in the galaxy, where $M_a$ ( $m_a$ )
denotes the mass of axion star ( axion ) and $T$ does temperature of the
electrons. We assume the number $10^{11}$ of the stars with $B\sim 10^{2}$G and
radius $\sim 3.5\times10^{5}$km in the galaxy. We also assume that a half of
the dark matter is composed of axion star. We show that the emission of the
radiation burst only arises in the atmosphere in which the plasma frequency
$m_p\simeq m_a$. The duration of the burst lasts for the period which it takes
the axion star to pass the region with $m_p\simeq m_a$. It would be longer than
$1$ second.
| [
{
"created": "Tue, 15 Mar 2022 01:07:47 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Apr 2022 00:19:19 GMT",
"version": "v2"
}
] | 2022-04-20 | [
[
"Iwazaki",
"Aiichi",
""
]
] | Axion is a promising candidate of dark matter in the universe. A fraction of dark matter axion may forms axion star with radius $\sim 10^2$km. We show that the axion star emits radiation burst by the collision with K and M types main sequence star in the Andromeda Galaxy. The emission arises in the atmosphere of the star, in which electrons coherently oscillate due to oscillating electric field of the axion star. The electric field is produced under magnetic field $B$ of the star. We estimate the flux density of the radiation $\sim 1.6\times 10^{-3}\mbox{Jy} (10^{-12}M_{\odot}/M_a)^2(10^{-5}\mbox{eV}/m_a)^3(B/10^2\mbox{G})^2\sqrt{3\times10^3\mbox{K}/T}$ and the rate of the collision per hour $\sim 0.06/\mbox{hour}\,(10^{-12}M_{\odot}/M_a)$ in the galaxy, where $M_a$ ( $m_a$ ) denotes the mass of axion star ( axion ) and $T$ does temperature of the electrons. We assume the number $10^{11}$ of the stars with $B\sim 10^{2}$G and radius $\sim 3.5\times10^{5}$km in the galaxy. We also assume that a half of the dark matter is composed of axion star. We show that the emission of the radiation burst only arises in the atmosphere in which the plasma frequency $m_p\simeq m_a$. The duration of the burst lasts for the period which it takes the axion star to pass the region with $m_p\simeq m_a$. It would be longer than $1$ second. |
hep-ph/0608282 | Pedro Miguel Martins Ferreira | A. Barroso, P. M. Ferreira, R. Santos and Joao P. Silva | Stability of the normal vacuum in multi-Higgs-doublet models | 21 pages | Phys.Rev.D74:085016,2006 | 10.1103/PhysRevD.74.085016 | null | hep-ph | null | We show that the vacuum structure of a generic multi-Higgs-doublet model
shares several important features with the vacuum structure of the two and
three Higgs-doublet model. In particular, one can still define the usual charge
breaking, spontaneous CP breaking and normal (charge and CP preserving)
stationary points. We analyse the possibility of charge or spontaneous CP
breaking, by studying the relative depth of the potential in each of the
possible stationary points.
| [
{
"created": "Fri, 25 Aug 2006 15:29:03 GMT",
"version": "v1"
},
{
"created": "Tue, 19 Sep 2006 09:38:42 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Barroso",
"A.",
""
],
[
"Ferreira",
"P. M.",
""
],
[
"Santos",
"R.",
""
],
[
"Silva",
"Joao P.",
""
]
] | We show that the vacuum structure of a generic multi-Higgs-doublet model shares several important features with the vacuum structure of the two and three Higgs-doublet model. In particular, one can still define the usual charge breaking, spontaneous CP breaking and normal (charge and CP preserving) stationary points. We analyse the possibility of charge or spontaneous CP breaking, by studying the relative depth of the potential in each of the possible stationary points. |
1604.03315 | Yuya Kaneta | Yuya Kaneta, Yusuke Shimizu, Morimitsu Tanimoto, Tsutomu T. Yanagida | Occam's Razor in Lepton Mass Matrices - The Sign of Universe's Baryon
Asymmetry - | Minor modification. 3 references are added | null | 10.1093/ptep/ptw079 | HUPD1603, IPMU16-0046 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the neutrino mass matrix based on the Occam's Razor approach in
the framework of the seesaw mechanism. We impose four zeros in the Dirac
neutrino mass matrix, which give the minimum number of parameters needed for
the observed neutrino masses and lepton mixing angles, while the charged lepton
mass matrix and the right-handed Majorana neutrino mass matrix are taken to be
real diagonal ones. The low-energy neutrino mass matrix has only seven physical
parameters. We show successful predictions for the mixing angle $\theta_{13}$
and the CP violating phase $\delta_{CP}$ with the normal mass hierarchy of
neutrinos by using the experimental data on the neutrino mass squared
differences, the mixing angles $\theta_{12}$ and $\theta_{23}$. The most
favored region of $\sin\theta_{13}$ is around $0.13\sim 0.15$, which is
completely consistent with the observed value. The CP violating phase
$\delta_{CP}$ is favored to be close to $\pm \pi/2$. We also discuss the
Majorana phases as well as the effective neutrino mass for the neutrinoless
double-beta decay $m_{ee}$, which is around $7\sim 8$ meV. It is extremely
remarkable that we can perform a "complete experiment" to determine the
low-energy neutrino mass matrix, since we have only seven physical parameters
in the neutrino mass matrix. In particular, two CP violating phases in the
neutrino mass matrix are directly given by two CP violating phases at high
energy. Thus, assuming the leptogenesis we can determine the sign of the cosmic
baryon in the universe from the low-energy experiments for the neutrino mass
matrix.
| [
{
"created": "Tue, 12 Apr 2016 09:20:54 GMT",
"version": "v1"
},
{
"created": "Sun, 17 Apr 2016 06:46:57 GMT",
"version": "v2"
}
] | 2016-07-06 | [
[
"Kaneta",
"Yuya",
""
],
[
"Shimizu",
"Yusuke",
""
],
[
"Tanimoto",
"Morimitsu",
""
],
[
"Yanagida",
"Tsutomu T.",
""
]
] | We discuss the neutrino mass matrix based on the Occam's Razor approach in the framework of the seesaw mechanism. We impose four zeros in the Dirac neutrino mass matrix, which give the minimum number of parameters needed for the observed neutrino masses and lepton mixing angles, while the charged lepton mass matrix and the right-handed Majorana neutrino mass matrix are taken to be real diagonal ones. The low-energy neutrino mass matrix has only seven physical parameters. We show successful predictions for the mixing angle $\theta_{13}$ and the CP violating phase $\delta_{CP}$ with the normal mass hierarchy of neutrinos by using the experimental data on the neutrino mass squared differences, the mixing angles $\theta_{12}$ and $\theta_{23}$. The most favored region of $\sin\theta_{13}$ is around $0.13\sim 0.15$, which is completely consistent with the observed value. The CP violating phase $\delta_{CP}$ is favored to be close to $\pm \pi/2$. We also discuss the Majorana phases as well as the effective neutrino mass for the neutrinoless double-beta decay $m_{ee}$, which is around $7\sim 8$ meV. It is extremely remarkable that we can perform a "complete experiment" to determine the low-energy neutrino mass matrix, since we have only seven physical parameters in the neutrino mass matrix. In particular, two CP violating phases in the neutrino mass matrix are directly given by two CP violating phases at high energy. Thus, assuming the leptogenesis we can determine the sign of the cosmic baryon in the universe from the low-energy experiments for the neutrino mass matrix. |
hep-ph/9708316 | Theory Group Member | Chao-shang Huang and C. S. Kim(Yonsei Univ & I.C.T.P.) | A Few Notes on Non-perturbative Parameters in Heavy Quark Expansion | 8 pages(LaTeX), 1 eps figure | J.Korean Phys.Soc.34:397-400,1999 | null | null | hep-ph | null | Non-perturbative parameters to the order ${\cal O}({1 \over m_Q})$ in HQET
expansion, $\bar{ \Lambda}$, $\lambda_1$ and $\lambda_2$, as well as the
masses, $m_b$ and $m_c$, are estimated phenomenologically from $B$ and $D$
meson system spectroscopy. We found relatively large value of $m_b$ and quite
small value of $\bar{ \Lambda}$ compared to previous estimates.
| [
{
"created": "Tue, 12 Aug 1997 07:00:37 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Aug 1997 05:34:19 GMT",
"version": "v2"
}
] | 2011-01-27 | [
[
"Huang",
"Chao-shang",
"",
"Yonsei Univ & I.C.T.P."
],
[
"Kim",
"C. S.",
"",
"Yonsei Univ & I.C.T.P."
]
] | Non-perturbative parameters to the order ${\cal O}({1 \over m_Q})$ in HQET expansion, $\bar{ \Lambda}$, $\lambda_1$ and $\lambda_2$, as well as the masses, $m_b$ and $m_c$, are estimated phenomenologically from $B$ and $D$ meson system spectroscopy. We found relatively large value of $m_b$ and quite small value of $\bar{ \Lambda}$ compared to previous estimates. |
1310.6178 | Luminita Mihaila | Luminita Mihaila | Precision Calculations in Supersymmetric Theories | 106 pages, 36 figures | Adv. High Energy Phys. 2013 (2013) 607807 | 10.1155/2013/607807 | TTP13-001, SFB/CPP-13-02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this review article we report on the newest developments in precision
calculations in supersymmetric theories. An important issue related to this
topic is the construction of a regularization scheme preserving simultaneously
gauge invariance and supersymmetry. In this context, we discuss in detail
dimensional reduction in component field formalism as it is currently the
preferred framework employed in the literature. Furthermore, we set special
emphasis on the application of multi-loop calculations to the analysis of gauge
coupling unification, the prediction of thelightest Higgs boson mass and the
computation of the hadronic Higgs production and decay rates in supersymmetric
models. Such precise theoretical calculations up to the fourth order in
perturbation theory are required in order to cope with the expected
experimental accuracy on the one hand, and to enable us to distinguish between
the predictions of the Standard Model and those of supersymmetric theories on
the other hand.
| [
{
"created": "Wed, 23 Oct 2013 10:49:20 GMT",
"version": "v1"
}
] | 2013-10-24 | [
[
"Mihaila",
"Luminita",
""
]
] | In this review article we report on the newest developments in precision calculations in supersymmetric theories. An important issue related to this topic is the construction of a regularization scheme preserving simultaneously gauge invariance and supersymmetry. In this context, we discuss in detail dimensional reduction in component field formalism as it is currently the preferred framework employed in the literature. Furthermore, we set special emphasis on the application of multi-loop calculations to the analysis of gauge coupling unification, the prediction of thelightest Higgs boson mass and the computation of the hadronic Higgs production and decay rates in supersymmetric models. Such precise theoretical calculations up to the fourth order in perturbation theory are required in order to cope with the expected experimental accuracy on the one hand, and to enable us to distinguish between the predictions of the Standard Model and those of supersymmetric theories on the other hand. |
1401.4765 | Ren-You Zhang | Chen Chong, Guo Lei, Ma Wen-Gan, Zhang Ren-You, Li Xiao-Zhou, and
Zhang Yu | Possible effects of the large extra dimensions on $ZZW$ production at
the LHC | 17 pages, 6 figures | Mod. Phys. Lett. A, Vol. 29, No. 31 (2014) 1450153 | 10.1142/S0217732314501533 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the possible large extra dimensions (LED) effects induced by
the Kaluza-Klein gravitons up to the QCD next-to-leading order (NLO) on $ZZW$
production at the large hadron collider (LHC). The integrated cross sections
and some kinematic distributions are presented in both the standard model (SM)
and the LED model. The numerical results demonstrate that the NLO QCD
corrections are sizeable and remarkably reduce the leading order (LO) LED
effect depending strongly on the phase space. The NLO LED relative
discrepancies of the total cross section could become sizable for the $ZZW$
production, if we apply proper event selection criteria. We find that the LO
result overestimates the LED effect and is insufficient to provide a believable
theoretical prediction.
| [
{
"created": "Mon, 20 Jan 2014 01:34:21 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Jul 2014 01:38:07 GMT",
"version": "v2"
},
{
"created": "Thu, 17 Jul 2014 07:37:32 GMT",
"version": "v3"
},
{
"created": "Wed, 22 Oct 2014 03:02:35 GMT",
"version": "v4"
},
{
"c... | 2014-10-24 | [
[
"Chong",
"Chen",
""
],
[
"Lei",
"Guo",
""
],
[
"Wen-Gan",
"Ma",
""
],
[
"Ren-You",
"Zhang",
""
],
[
"Xiao-Zhou",
"Li",
""
],
[
"Yu",
"Zhang",
""
]
] | We investigate the possible large extra dimensions (LED) effects induced by the Kaluza-Klein gravitons up to the QCD next-to-leading order (NLO) on $ZZW$ production at the large hadron collider (LHC). The integrated cross sections and some kinematic distributions are presented in both the standard model (SM) and the LED model. The numerical results demonstrate that the NLO QCD corrections are sizeable and remarkably reduce the leading order (LO) LED effect depending strongly on the phase space. The NLO LED relative discrepancies of the total cross section could become sizable for the $ZZW$ production, if we apply proper event selection criteria. We find that the LO result overestimates the LED effect and is insufficient to provide a believable theoretical prediction. |
1311.5132 | Jean-Baptiste Flament | Giacomo Cacciapaglia, Aldo Deandrea, Guillaume Drieu La Rochelle,
Jean-Baptiste Flament | Searching for a lighter Higgs: parametrisation and sample tests | 15 p, v2: References added. Addition of the LEP analysis
hep-ex/0107034 (absent in HiggsBounds): the NMSSM plots from Fig1 (top row)
and Fig2 (top row) are slightly altered at light h1 masses. Other plots and
the overall conclusions stay the same. Small corrections to the text | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The structure of the Higgs sector is a major issue in the quest of a detailed
description of the electroweak interactions. Most of the effort is devoted to
the study of the standard model--like Higgs boson at 126 GeV, however the
experimental collaborations at the LHC are also searching for extra scalar
particles whose presence may hint to an extended Higgs sector, typical of many
extensions of the standard model. We study a model independent parametrisation
of a scalar particle lighter than the 126 GeV Higgs boson, which may be easily
implemented in the ongoing searches by ATLAS and CMS. Indeed many effective
Lagrangians/parametrisations used at present for the description of the Higgs
sector implicitly assume that no light particles other than the standard model
ones are present in the spectrum. We therefore introduce a parametrisation of a
two scalars model, one corresponding to the 126 GeV Higgs boson and the other
to a lighter scalar. After the introduction of such a tool, we consider two
typical examples falling in this category, in order to illustrate the use of
our formalism: the two Higgs doublet model and the next to minimal
supersymmetric standard model. Our results agree with the specific studies
performed for these models. Furthermore, employing such a generic
parametrisation allows us to translate the bounds to any model beyond the
standard model falling into this class.
| [
{
"created": "Wed, 20 Nov 2013 16:48:34 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Dec 2013 17:42:49 GMT",
"version": "v2"
}
] | 2013-12-18 | [
[
"Cacciapaglia",
"Giacomo",
""
],
[
"Deandrea",
"Aldo",
""
],
[
"La Rochelle",
"Guillaume Drieu",
""
],
[
"Flament",
"Jean-Baptiste",
""
]
] | The structure of the Higgs sector is a major issue in the quest of a detailed description of the electroweak interactions. Most of the effort is devoted to the study of the standard model--like Higgs boson at 126 GeV, however the experimental collaborations at the LHC are also searching for extra scalar particles whose presence may hint to an extended Higgs sector, typical of many extensions of the standard model. We study a model independent parametrisation of a scalar particle lighter than the 126 GeV Higgs boson, which may be easily implemented in the ongoing searches by ATLAS and CMS. Indeed many effective Lagrangians/parametrisations used at present for the description of the Higgs sector implicitly assume that no light particles other than the standard model ones are present in the spectrum. We therefore introduce a parametrisation of a two scalars model, one corresponding to the 126 GeV Higgs boson and the other to a lighter scalar. After the introduction of such a tool, we consider two typical examples falling in this category, in order to illustrate the use of our formalism: the two Higgs doublet model and the next to minimal supersymmetric standard model. Our results agree with the specific studies performed for these models. Furthermore, employing such a generic parametrisation allows us to translate the bounds to any model beyond the standard model falling into this class. |
0810.1247 | Krzysztof M. Graczyk | Krzysztof M. Graczyk | Resonance contribution to single pion production in neutrino-nucleon
scattering | 10 pages, 3 figures, talk given at Twenty Seventh International
Workshop on Nuclear Theory, June 23 - 28, 2008, Rila mountains, Bulgaria | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Single pion production in neutrino-nucleon scattering is discussed. The
neutrino energies characteristic for T2K project are considered. Two new
parameterizations of $C_5^A$ axial form factor are proposed. Both of them are
obtained in simultaneous fit to ANL and BNL data. One of them (which fits
better to BNL data) leads to $d\sigma/dQ^2$ differential cross section which is
significantly reduced at low $Q^2$.
| [
{
"created": "Tue, 7 Oct 2008 17:39:41 GMT",
"version": "v1"
}
] | 2008-10-08 | [
[
"Graczyk",
"Krzysztof M.",
""
]
] | Single pion production in neutrino-nucleon scattering is discussed. The neutrino energies characteristic for T2K project are considered. Two new parameterizations of $C_5^A$ axial form factor are proposed. Both of them are obtained in simultaneous fit to ANL and BNL data. One of them (which fits better to BNL data) leads to $d\sigma/dQ^2$ differential cross section which is significantly reduced at low $Q^2$. |
hep-ph/9502251 | null | R. Roncaglia, D. B. Lichtenberg, and E. Predazzi | PREDICTING THE MASSES OF BARYONS CONTAINING ONE OR TWO HEAVY QUARKS | 11 pages, Plain TeX, 2 figures (not included, available on request
from lichten@photon.physics.indiana.edu) | Phys.Rev.D52:1722-1725,1995 | 10.1103/PhysRevD.52.1722 | IUHET 293, IU/NTC 95-03, DFTT--95/7. | hep-ph | null | The Feynman-Hellmann theorem and semiempirical mass formulas are used to
predict the masses of baryons containing one or two heavy quarks. In
particular, the mass of the $\Lambda_b$ is predicted to be $5620 \pm 40$ MeV, a
value consistent with measurements.
| [
{
"created": "Wed, 8 Feb 1995 05:00:44 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Roncaglia",
"R.",
""
],
[
"Lichtenberg",
"D. B.",
""
],
[
"Predazzi",
"E.",
""
]
] | The Feynman-Hellmann theorem and semiempirical mass formulas are used to predict the masses of baryons containing one or two heavy quarks. In particular, the mass of the $\Lambda_b$ is predicted to be $5620 \pm 40$ MeV, a value consistent with measurements. |
hep-ph/9805216 | Michael Melles | Michael Melles | Massive Fermionic Corrections to the Heavy Quark Potential Through Two
Loops | 37 pages, Latex2e, uses bibtex for references and eps-figure
environment epsfig | Phys.Rev.D58:114004,1998 | 10.1103/PhysRevD.58.114004 | SLAC-PUB 7652, DTP-98-18 | hep-ph | null | A physically defined effective charge can incorporate quark masses
analytically at the flavor thresholds. Therefore, no matching conditions are
required for the evolution of the strong coupling constant through these
thresholds. In this paper, we calculate the massive fermionic corrections to
the heavy quark potential through two loops. The calculation uses a mixed
approach of analytical, computer-algebraic and numerical tools including Monte
Carlo integration of finite terms. Strong consistency checks are performed by
ensuring the proper cancellation of all non-local divergences by the
appropriate counterterms and by comparing with the massless limit. The size of
the effect for the (gauge invariant) fermionic part of $\alpha_V (q^2,m^2) $
relative to the massless case at the charm and bottom flavor thresholds is
found to be of order 33%.
| [
{
"created": "Mon, 4 May 1998 17:09:10 GMT",
"version": "v1"
}
] | 2011-01-25 | [
[
"Melles",
"Michael",
""
]
] | A physically defined effective charge can incorporate quark masses analytically at the flavor thresholds. Therefore, no matching conditions are required for the evolution of the strong coupling constant through these thresholds. In this paper, we calculate the massive fermionic corrections to the heavy quark potential through two loops. The calculation uses a mixed approach of analytical, computer-algebraic and numerical tools including Monte Carlo integration of finite terms. Strong consistency checks are performed by ensuring the proper cancellation of all non-local divergences by the appropriate counterterms and by comparing with the massless limit. The size of the effect for the (gauge invariant) fermionic part of $\alpha_V (q^2,m^2) $ relative to the massless case at the charm and bottom flavor thresholds is found to be of order 33%. |
1611.02387 | Marek Lewicki | Marek Lewicki | EW baryogenesis via DM | to appear in the Proceedings of "Rencontres de Blois 2016" | null | null | ADP-16-41/T997 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the impact of a swifter cosmological expansion induced by modified
cosmological history of the universe on scenarios realising electroweak
baryogenesis. We detail the possible experimental bounds one can place on such
cosmological modification and show how the detection capabilities of particle
models are modified within these bounds. On the particle physics side we focus
on the Standard Model supplemented by a dimension six operator which directly
modifies the Higgs potential. We show that due to the cosmological
modification, electroweak baryogenesis in this model can be realized, with the
modification of the triple Higgs coupling below HL-LHC sensitivity.
| [
{
"created": "Tue, 8 Nov 2016 04:51:35 GMT",
"version": "v1"
}
] | 2016-11-09 | [
[
"Lewicki",
"Marek",
""
]
] | We discuss the impact of a swifter cosmological expansion induced by modified cosmological history of the universe on scenarios realising electroweak baryogenesis. We detail the possible experimental bounds one can place on such cosmological modification and show how the detection capabilities of particle models are modified within these bounds. On the particle physics side we focus on the Standard Model supplemented by a dimension six operator which directly modifies the Higgs potential. We show that due to the cosmological modification, electroweak baryogenesis in this model can be realized, with the modification of the triple Higgs coupling below HL-LHC sensitivity. |
1604.04299 | Christoph Englert | Philippe Brax, Clare Burrage, Christoph Englert, Michael Spannowsky | LHC Signatures Of Scalar Dark Energy | 10 pages, 8 figures | Phys. Rev. D 94, 084054 (2016) | 10.1103/PhysRevD.94.084054 | IPPP/16/31, DCPT/16/62 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Scalar dark energy fields that couple to the Standard Model can give rise to
observable signatures at the LHC. In this work we show that $t\bar t+$missing
energy and mono-jet searches are suitable probes in the limit where the dark
energy scalar is stable on collider distances. We discuss the prospects of
distinguishing the dark energy character of new physics signals from dark
matter signatures and the possibility of probing the self-interactions of the
dark energy sector.
| [
{
"created": "Thu, 14 Apr 2016 20:28:01 GMT",
"version": "v1"
}
] | 2016-11-09 | [
[
"Brax",
"Philippe",
""
],
[
"Burrage",
"Clare",
""
],
[
"Englert",
"Christoph",
""
],
[
"Spannowsky",
"Michael",
""
]
] | Scalar dark energy fields that couple to the Standard Model can give rise to observable signatures at the LHC. In this work we show that $t\bar t+$missing energy and mono-jet searches are suitable probes in the limit where the dark energy scalar is stable on collider distances. We discuss the prospects of distinguishing the dark energy character of new physics signals from dark matter signatures and the possibility of probing the self-interactions of the dark energy sector. |
0910.3710 | Mart\'in Gonz\'alez-Alonso | Martin Gonzalez-Alonso | New Physics bounds from the combination of CKM-universality and high
energy data | Talk given at the FLAVIAnet topical workshop 'Low energy constraints
on extensions of the Standard Model' (Kazimierz, Poland), July 2009. 6 pages | Acta Phys.Polon.Supp.3:159-164,2010 | null | IFIC/09-51, FTUV/09-1019 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Through an effective field theory approach, we analyze the new physics
corrections to muon and beta decays and their effects on the extractions of
V_ud and V_us. Assuming nearly flavor blind NP interactions, we find that the
only quantity sensitive to NP is Delta_CKM = |V_ud|^2 + |V_us|^2 + |V_ub|^2 -
1, that receives contributions from four short distance operators. The
phenomenological bound Delta_CKM = (-1 \pm 6) 10^-4 provides strong constraints
on all four operators, corresponding to an effective scale Lambda > 11 TeV (90%
CL). Depending on the operator, this constraint is at the same level or better
than that generated by the Z pole observables.
| [
{
"created": "Mon, 19 Oct 2009 21:43:21 GMT",
"version": "v1"
}
] | 2010-11-02 | [
[
"Gonzalez-Alonso",
"Martin",
""
]
] | Through an effective field theory approach, we analyze the new physics corrections to muon and beta decays and their effects on the extractions of V_ud and V_us. Assuming nearly flavor blind NP interactions, we find that the only quantity sensitive to NP is Delta_CKM = |V_ud|^2 + |V_us|^2 + |V_ub|^2 - 1, that receives contributions from four short distance operators. The phenomenological bound Delta_CKM = (-1 \pm 6) 10^-4 provides strong constraints on all four operators, corresponding to an effective scale Lambda > 11 TeV (90% CL). Depending on the operator, this constraint is at the same level or better than that generated by the Z pole observables. |
hep-ph/9610340 | Mar Bastero Gil | M. Bastero-Gil | Perturbative Unification and Low Energy Precision Data | 27 pages, Revtex-3.0 | null | null | null | hep-ph | null | More precise unification predictions require going beyond the lowest order,
including 2-loop running of the couplings and a correct treatment of threshold
effects. Here we revised two different approaches to deal with light
thresholds, based on different choices of the renormalization scheme, \bar{MS}
and effective couplings. We show the equivalence of both approaches in making
predictions when thresholds are taking properly into account.
| [
{
"created": "Sun, 13 Oct 1996 18:29:41 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bastero-Gil",
"M.",
""
]
] | More precise unification predictions require going beyond the lowest order, including 2-loop running of the couplings and a correct treatment of threshold effects. Here we revised two different approaches to deal with light thresholds, based on different choices of the renormalization scheme, \bar{MS} and effective couplings. We show the equivalence of both approaches in making predictions when thresholds are taking properly into account. |
1405.2925 | Junwu Huang | Asimina Arvanitaki, Junwu Huang, Ken Van Tilburg | Searching for dilaton dark matter with atomic clocks | 17 pages, 10 figures | PhysRevD.91.015015,2015 | 10.1103/PhysRevD.91.015015 | null | hep-ph hep-ex physics.atom-ph physics.optics | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose an experiment to search for ultralight scalar dark matter (DM)
with dilatonic interactions. Such couplings can arise for the dilaton as well
as for moduli and axion-like particles in the presence of CP violation.
Ultralight dilaton DM acts as a background field that can cause tiny but
coherent oscillations in Standard Model parameters such as the fine structure
constant and the proton-electron mass ratio. These minute variations can be
detected through precise frequency comparisons of atomic clocks. Our experiment
extends current searches for drifts in fundamental constants to the
well-motivated high-frequency regime. Our proposed setups can probe scalars
lighter than 10^-15 eV with discovery potential of dilatonic couplings as weak
as 10^-11 times the strength of gravity, improving current equivalence
principle bounds by up to 8 orders of magnitude. We point out potential 10^4
sensitivity enhancements with future optical and nuclear clocks, as well as
possible signatures in gravitational wave detectors. Finally, we discuss
cosmological constraints and astrophysical hints of ultralight scalar DM, and
show they are complimentary to and compatible with the parameter range
accessible to our proposed laboratory experiments.
| [
{
"created": "Mon, 12 May 2014 20:00:03 GMT",
"version": "v1"
},
{
"created": "Fri, 30 Jan 2015 23:22:40 GMT",
"version": "v2"
}
] | 2015-02-03 | [
[
"Arvanitaki",
"Asimina",
""
],
[
"Huang",
"Junwu",
""
],
[
"Van Tilburg",
"Ken",
""
]
] | We propose an experiment to search for ultralight scalar dark matter (DM) with dilatonic interactions. Such couplings can arise for the dilaton as well as for moduli and axion-like particles in the presence of CP violation. Ultralight dilaton DM acts as a background field that can cause tiny but coherent oscillations in Standard Model parameters such as the fine structure constant and the proton-electron mass ratio. These minute variations can be detected through precise frequency comparisons of atomic clocks. Our experiment extends current searches for drifts in fundamental constants to the well-motivated high-frequency regime. Our proposed setups can probe scalars lighter than 10^-15 eV with discovery potential of dilatonic couplings as weak as 10^-11 times the strength of gravity, improving current equivalence principle bounds by up to 8 orders of magnitude. We point out potential 10^4 sensitivity enhancements with future optical and nuclear clocks, as well as possible signatures in gravitational wave detectors. Finally, we discuss cosmological constraints and astrophysical hints of ultralight scalar DM, and show they are complimentary to and compatible with the parameter range accessible to our proposed laboratory experiments. |
hep-ph/9610417 | J. Gunion | J.F. Gunion and P.C. Martin (U.C. Davis) | Measuring the Higgs to Photon-Photon Branching Ratio at the Next Linear
$e^+e^-$ Collider | 5 pages, full postscript file also available via anonymous ftp at
ftp://ucdhep.ucdavis.edu/gunion/htogamgam_sm96.ps To appear in ``Proceedings
of the 1996 DPF/DPB Summer Study on New Directions for High Energy Physics'' | ECONF C960625:LTH104,1996 | null | UCD-96-34 | hep-ph hep-ex | null | We examine the prospects for measuring the photon-photon branching ratio of a
Standard-Model-like Higgs boson ($h$) at the Next Linear $e^+e^-$ Collider when
the Higgs boson is produced via $W^+W^-$--fusion: $e^+e^-\to\nu_e \bar\nu_e h$.
In particular, we study the accuracy of such a measurement and the statistical
significance of the associated signal as a function of the electromagnetic
calorimeter resolution and the Higgs boson mass. We compare results for the
$W^+W^-$--fusion production/measurement mode with the results obtained for the
$e^+e^-\rightarrow Z^*\rightarrow Z h$ production/measurement mode in a
parallel earlier study.
| [
{
"created": "Fri, 18 Oct 1996 20:00:22 GMT",
"version": "v1"
}
] | 2011-04-15 | [
[
"Gunion",
"J. F.",
"",
"U.C. Davis"
],
[
"Martin",
"P. C.",
"",
"U.C. Davis"
]
] | We examine the prospects for measuring the photon-photon branching ratio of a Standard-Model-like Higgs boson ($h$) at the Next Linear $e^+e^-$ Collider when the Higgs boson is produced via $W^+W^-$--fusion: $e^+e^-\to\nu_e \bar\nu_e h$. In particular, we study the accuracy of such a measurement and the statistical significance of the associated signal as a function of the electromagnetic calorimeter resolution and the Higgs boson mass. We compare results for the $W^+W^-$--fusion production/measurement mode with the results obtained for the $e^+e^-\rightarrow Z^*\rightarrow Z h$ production/measurement mode in a parallel earlier study. |
1706.04037 | Natascia Vignaroli | Emiliano Molinaro, Francesco Sannino, Anders Eller Thomsen, Natascia
Vignaroli | Uncovering new strong dynamics via topological interactions at the 100
TeV collider | 24 pages, 5 figures. Matches published version | Phys. Rev. D 96, 075040 (2017) | 10.1103/PhysRevD.96.075040 | CP3-ORIGINS-2017-021-DNRF90, CERN-TH-2017-127 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In models of composite Higgs dynamics new composite pseudoscalars can
interact with the Higgs and electroweak gauge bosons via anomalous
interactions, stemming from the topological sector of the underlying theory. We
show that a future 100 TeV proton-proton collider (FCC-pp) will be able to test
this important sector and thus shed light on the strong dynamics which
generates the Higgs and other composite states. To elucidate our results we
focus on the topological interactions of a minimal composite Higgs model with a
fermionic ultraviolet completion, based on the coset
$\text{SU}(4)/\text{Sp}(4)$. We suggest the strategy to test these interactions
at the FCC-pp and analyse the expected reach.
| [
{
"created": "Tue, 13 Jun 2017 13:09:28 GMT",
"version": "v1"
},
{
"created": "Sun, 29 Oct 2017 14:47:32 GMT",
"version": "v2"
}
] | 2017-10-31 | [
[
"Molinaro",
"Emiliano",
""
],
[
"Sannino",
"Francesco",
""
],
[
"Thomsen",
"Anders Eller",
""
],
[
"Vignaroli",
"Natascia",
""
]
] | In models of composite Higgs dynamics new composite pseudoscalars can interact with the Higgs and electroweak gauge bosons via anomalous interactions, stemming from the topological sector of the underlying theory. We show that a future 100 TeV proton-proton collider (FCC-pp) will be able to test this important sector and thus shed light on the strong dynamics which generates the Higgs and other composite states. To elucidate our results we focus on the topological interactions of a minimal composite Higgs model with a fermionic ultraviolet completion, based on the coset $\text{SU}(4)/\text{Sp}(4)$. We suggest the strategy to test these interactions at the FCC-pp and analyse the expected reach. |
1805.08176 | Maarten F. L. Golterman | Diogo Boito, Maarten Golterman, Alexander Keshavarzi, Kim Maltman,
Daisuke Nomura, Santiago Peris, Thomas Teubner | The strong coupling from $e^+e^-\to$ hadrons below charm | 31 pages, 9 figures | Phys. Rev. D 98, 074030 (2018) | 10.1103/PhysRevD.98.074030 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use a new compilation of the hadronic $R$-ratio from available data for
the process $e^+e^-\to\mbox{hadrons}$ to determine the strong coupling,
$\alpha_s$. We make use of all data for the $R$-ratio from threshold to a
center-of-mass energy of 2 GeV by employing finite-energy sum rules. Data above
2 GeV, for which at present far fewer high-precision experimental data are
available, do not provide much additional constraint but are fully consistent
with the values for $\alpha_s$ we obtain. Quoting our results at the $\tau$
mass to facilitate comparison to the results obtained from analogous analyses
of hadronic $\tau$-decay data, we find $\alpha_s(m_\tau^2)=0.298\pm 0.016\pm
0.006$ in fixed-order perturbation theory, and $\alpha_s(m_\tau^2)=0.304\pm
0.018\pm 0.006$ in contour-improved perturbation theory, where the first error
is statistical, and the second error reflects our estimate of various
systematic effects. These values are in good agreement with a recent
determination from the OPAL and ALEPH data for hadronic $\tau$ decays.
| [
{
"created": "Mon, 21 May 2018 16:59:10 GMT",
"version": "v1"
}
] | 2018-11-07 | [
[
"Boito",
"Diogo",
""
],
[
"Golterman",
"Maarten",
""
],
[
"Keshavarzi",
"Alexander",
""
],
[
"Maltman",
"Kim",
""
],
[
"Nomura",
"Daisuke",
""
],
[
"Peris",
"Santiago",
""
],
[
"Teubner",
"Thomas",
""
]
] | We use a new compilation of the hadronic $R$-ratio from available data for the process $e^+e^-\to\mbox{hadrons}$ to determine the strong coupling, $\alpha_s$. We make use of all data for the $R$-ratio from threshold to a center-of-mass energy of 2 GeV by employing finite-energy sum rules. Data above 2 GeV, for which at present far fewer high-precision experimental data are available, do not provide much additional constraint but are fully consistent with the values for $\alpha_s$ we obtain. Quoting our results at the $\tau$ mass to facilitate comparison to the results obtained from analogous analyses of hadronic $\tau$-decay data, we find $\alpha_s(m_\tau^2)=0.298\pm 0.016\pm 0.006$ in fixed-order perturbation theory, and $\alpha_s(m_\tau^2)=0.304\pm 0.018\pm 0.006$ in contour-improved perturbation theory, where the first error is statistical, and the second error reflects our estimate of various systematic effects. These values are in good agreement with a recent determination from the OPAL and ALEPH data for hadronic $\tau$ decays. |
hep-ph/0510073 | Chang-Hwan Lee | G.E. Brown, C.-H. Lee, H.-J. Park, M. Rho | Study of Strangeness Condensation by Expanding About the Fixed Point of
the Harada-Yamawaki Vector Manifestation | 4 pages | Phys.Rev.Lett. 96 (2006) 062303 | 10.1103/PhysRevLett.96.062303 | null | hep-ph nucl-th | null | Building on, and extending, the result of a higher-order in-medium chiral
perturbation theory combined with renormalization group arguments and a variety
of observations of the vector manifestation of Harada-Yamawaki hidden local
symmetry theory, we obtain a surprisingly simple description of kaon
condensation by fluctuating around the "vector manifestation (VM)" fixed point
identified to be the chiral restoration point. Our development establishes that
strangeness condensation takes place at about 3 n_0 where n_0 is nuclear matter
density. This result depends only on the renoramlization-group (RG) behavior of
the vector interactions, other effects involved in fluctuating about the bare
vacuum in so many previous calculations being "irrelevant" in the RG about the
fixed point. Our results have major effects on the collapse of neutron stars
into black holes.
| [
{
"created": "Thu, 6 Oct 2005 11:16:56 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Brown",
"G. E.",
""
],
[
"Lee",
"C. -H.",
""
],
[
"Park",
"H. -J.",
""
],
[
"Rho",
"M.",
""
]
] | Building on, and extending, the result of a higher-order in-medium chiral perturbation theory combined with renormalization group arguments and a variety of observations of the vector manifestation of Harada-Yamawaki hidden local symmetry theory, we obtain a surprisingly simple description of kaon condensation by fluctuating around the "vector manifestation (VM)" fixed point identified to be the chiral restoration point. Our development establishes that strangeness condensation takes place at about 3 n_0 where n_0 is nuclear matter density. This result depends only on the renoramlization-group (RG) behavior of the vector interactions, other effects involved in fluctuating about the bare vacuum in so many previous calculations being "irrelevant" in the RG about the fixed point. Our results have major effects on the collapse of neutron stars into black holes. |
1304.0846 | Ping Wang | P. Wang and X. G. Wang | Study on X(3872) from effective field theory with pion exchange
interaction | 5 pages, 4 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study $D\bar{D}^*$ ($D^*\bar{D}$) scattering in the framework of
unitarized heavy meson chiral perturbation theory with pion exchange and a
contact interaction. $^3S_1-$$^3D_1$ mixing effects are taken into account. A
loosely bound state X(3872), with the pole position being
$M_{pole}=(3871.70-i0.39)\mathrm{MeV}$, is found. The result is not sensitive
to the strength of the contact interaction. Our calculation provides a
theoretical confirmation of the existence of the $1^{++}$ state X(3872). The
light quark mass dependence of the pole position indicates it has a
predominately $D\bar{D}^*$ ($D^*\bar{D}$) molecular nature. When the $\pi$ mass
is larger than 142 MeV, the pole disappears which makes impossible the lattice
simulation of this state at large quark mass.
| [
{
"created": "Wed, 3 Apr 2013 05:41:29 GMT",
"version": "v1"
}
] | 2013-04-04 | [
[
"Wang",
"P.",
""
],
[
"Wang",
"X. G.",
""
]
] | We study $D\bar{D}^*$ ($D^*\bar{D}$) scattering in the framework of unitarized heavy meson chiral perturbation theory with pion exchange and a contact interaction. $^3S_1-$$^3D_1$ mixing effects are taken into account. A loosely bound state X(3872), with the pole position being $M_{pole}=(3871.70-i0.39)\mathrm{MeV}$, is found. The result is not sensitive to the strength of the contact interaction. Our calculation provides a theoretical confirmation of the existence of the $1^{++}$ state X(3872). The light quark mass dependence of the pole position indicates it has a predominately $D\bar{D}^*$ ($D^*\bar{D}$) molecular nature. When the $\pi$ mass is larger than 142 MeV, the pole disappears which makes impossible the lattice simulation of this state at large quark mass. |
1905.13318 | Kyohei Mukaida | Valerie Domcke, Benedict von Harling, Enrico Morgante, Kyohei Mukaida | Baryogenesis from axion inflation | 19 pages, 6 figures; v2: published version | JCAP10(2019)032 | 10.1088/1475-7516/2019/10/032 | DESY 19-084 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The coupling of an axion-like particle driving inflation to the Standard
Model particle content through a Chern-Simons term generically sources a dual
production of massless helical gauge fields and chiral fermions. We demonstrate
that the interplay of these two components results in a highly predictive
baryogenesis model, which requires no further ingredients beyond the Standard
Model. If the helicity stored in the hyper magnetic field and the effective
chemical potential induced by the chiral fermion production are large enough to
avoid magnetic diffusion from the thermal plasma but small enough to
sufficiently delay the chiral plasma instability, then the non-vanishing
helicity survives until the electroweak phase transition and sources a net
baryon asymmetry which is in excellent agreement with the observed value. If
any of these two conditions is violated, the final baryon asymmetry vanishes.
The observed baryon asymmetry can be reproduced if the energy scale of
inflation is around $H_\text{inf} \sim 10^{10}$ - $10^{12}$ GeV with a moderate
dependence on inflation model parameters.
| [
{
"created": "Thu, 30 May 2019 21:25:13 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Oct 2019 00:07:06 GMT",
"version": "v2"
}
] | 2019-10-16 | [
[
"Domcke",
"Valerie",
""
],
[
"von Harling",
"Benedict",
""
],
[
"Morgante",
"Enrico",
""
],
[
"Mukaida",
"Kyohei",
""
]
] | The coupling of an axion-like particle driving inflation to the Standard Model particle content through a Chern-Simons term generically sources a dual production of massless helical gauge fields and chiral fermions. We demonstrate that the interplay of these two components results in a highly predictive baryogenesis model, which requires no further ingredients beyond the Standard Model. If the helicity stored in the hyper magnetic field and the effective chemical potential induced by the chiral fermion production are large enough to avoid magnetic diffusion from the thermal plasma but small enough to sufficiently delay the chiral plasma instability, then the non-vanishing helicity survives until the electroweak phase transition and sources a net baryon asymmetry which is in excellent agreement with the observed value. If any of these two conditions is violated, the final baryon asymmetry vanishes. The observed baryon asymmetry can be reproduced if the energy scale of inflation is around $H_\text{inf} \sim 10^{10}$ - $10^{12}$ GeV with a moderate dependence on inflation model parameters. |
2206.06911 | Priyank Kaushik | Priyank Kaushik, Vatsalya Vaibhav, Tejinder P. Singh | An $E_8 \otimes E_8$ Unification of the Standard Model with
Pre-Gravitation, on an Exceptional Lie algebra - Valued Space | v3: 31 pages, significantly revised to include Section 1, Section
6.3, and Section 7 | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose an $E_8 \otimes E_8$ unification of the standard model with
pre-gravitation, on an exceptional Lie algebra-valued space. Each of the $E_8$
has in its branching an $SU(3)$ for space-time and an $SU(3)$ for three fermion
generations. The first $E_8$ further branches to the standard model $SU(3)_c
\otimes SU(2)_L \otimes U(1)_Y$ and describes the gauge bosons, Higgs and the
left chiral fermions of the standard model. The second $E_8$ further branches
into a right-handed counterpart (pre-gravitation) $SU(3)_{grav}\otimes SU(2)_R
\otimes U(1)_g$ of the standard model, and describes right chiral fermions, a
Higgs, and twelve gauge bosons associated with pre-gravitation, from which
general relativity is emergent. We account for 208 out of the 496 degrees of
freedom of $E_8 \otimes E_8$ and propose an interpretation for the remaining
288, motivated by the trace dynamics Lagrangian of our theory. We explain how
the two copies of $SU(3)_{spacetime}$ together give rise to a 6D spacetime with
signature $(3,3)$ which upon symmetry breaking gives rise to our 4D spacetime
and to a second 4D anti-spacetime with flipped signature.
| [
{
"created": "Tue, 14 Jun 2022 15:15:58 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Nov 2022 15:42:14 GMT",
"version": "v2"
},
{
"created": "Sat, 6 Jul 2024 19:56:59 GMT",
"version": "v3"
}
] | 2024-07-09 | [
[
"Kaushik",
"Priyank",
""
],
[
"Vaibhav",
"Vatsalya",
""
],
[
"Singh",
"Tejinder P.",
""
]
] | We propose an $E_8 \otimes E_8$ unification of the standard model with pre-gravitation, on an exceptional Lie algebra-valued space. Each of the $E_8$ has in its branching an $SU(3)$ for space-time and an $SU(3)$ for three fermion generations. The first $E_8$ further branches to the standard model $SU(3)_c \otimes SU(2)_L \otimes U(1)_Y$ and describes the gauge bosons, Higgs and the left chiral fermions of the standard model. The second $E_8$ further branches into a right-handed counterpart (pre-gravitation) $SU(3)_{grav}\otimes SU(2)_R \otimes U(1)_g$ of the standard model, and describes right chiral fermions, a Higgs, and twelve gauge bosons associated with pre-gravitation, from which general relativity is emergent. We account for 208 out of the 496 degrees of freedom of $E_8 \otimes E_8$ and propose an interpretation for the remaining 288, motivated by the trace dynamics Lagrangian of our theory. We explain how the two copies of $SU(3)_{spacetime}$ together give rise to a 6D spacetime with signature $(3,3)$ which upon symmetry breaking gives rise to our 4D spacetime and to a second 4D anti-spacetime with flipped signature. |
hep-ph/9312239 | Santiago Peris | S. Peris | Higher-Order Corrections to the Large-$N_c$ Bound on
$M_{\eta}/M_{\eta'}$ | 8 pages, uses phyzzx, CERN-TH.7109/93 | Phys.Lett. B324 (1994) 442-445 | 10.1016/0370-2693(94)90220-8 | null | hep-ph | null | Next-to-leading $1/\N$ corrections to the upper bound on $M_{\eta}/M_{\eta
'}$ recently obtained by Georgi are considered. These corrections are just what
is needed to reconcile the bound with the observed $\eta$ and $\eta'$ masses.
| [
{
"created": "Tue, 7 Dec 1993 16:24:17 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Peris",
"S.",
""
]
] | Next-to-leading $1/\N$ corrections to the upper bound on $M_{\eta}/M_{\eta '}$ recently obtained by Georgi are considered. These corrections are just what is needed to reconcile the bound with the observed $\eta$ and $\eta'$ masses. |
hep-ph/9909531 | A. A. Arkhipov | A.A. Arkhipov | What Can We Learn from the Study of Single Diffractive Dissociation at
High Energies? | LaTex2e,35 pages,11 figures,The talk presented at the VIIIth Blois
Workshop on Elastic and Diffractive Scattering, Protvino, Russia, June
28-July 2,1999 | null | 10.1142/9789812817624_0012 | null | hep-ph | null | The fundamental relations in the dynamics of single diffraction dissociation
and elastic scattering at high energies are discussed.
| [
{
"created": "Tue, 28 Sep 1999 14:13:32 GMT",
"version": "v1"
}
] | 2016-11-23 | [
[
"Arkhipov",
"A. A.",
""
]
] | The fundamental relations in the dynamics of single diffraction dissociation and elastic scattering at high energies are discussed. |
hep-ph/9902425 | null | David H Lyth (Lancaster) | Models of inflation and their predictions | Latex 5 pages. To appear in Particle Physics and the Early Universe
(COSMO99), AIP (1999) | null | 10.1063/1.59442 | LANCS-TH/9903 | hep-ph | null | Taking field theory seriously, inflation model-building is difficult but not
impossible. The observed value of the spectral index of the adiabatic density
perturbation is starting to discriminate between models, and may well pick out
a unique one in the forseeable future.
| [
{
"created": "Mon, 22 Feb 1999 17:26:46 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Lyth",
"David H",
"",
"Lancaster"
]
] | Taking field theory seriously, inflation model-building is difficult but not impossible. The observed value of the spectral index of the adiabatic density perturbation is starting to discriminate between models, and may well pick out a unique one in the forseeable future. |
1012.3167 | Gil Paz | Michael Benzke (Mainz U.), Seung J. Lee (Weizmann Institute), Matthias
Neubert (Mainz U.), and Gil Paz (U. Chicago) | Long-Distance Dominance of the CP Asymmetry in B->X_{s,d}+gamma Decays | 4 pages | Phys.Rev.Lett.106:141801,2011 | 10.1103/PhysRevLett.106.141801 | MZ-TH/10-45, EFI Preprint 10-30 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that in the Standard Model the parametrically leading (by a factor
1/alpha_s) contribution to the inclusive CP asymmetry in B->X_{s,d}+gamma
decays arises from a long-distance effect in the interference of the
electromagnetic dipole amplitude with the amplitude for an up-quark penguin
transition accompanied by soft gluon emission. This contribution is governed by
a single hadronic parameter Lambda_{17}^u related to a matrix elements of a
non-local operator. In view of current experimental data, a future precision
measurement of the flavor-averaged CP asymmetry in B->X_s+gamma will signal the
presence of new physics only if a value below -2% is found. A cleaner probe of
new physics is offered by the difference of the CP asymmetries in charged
versus neutral B-meson decays.
| [
{
"created": "Tue, 14 Dec 2010 21:00:11 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Apr 2011 21:27:22 GMT",
"version": "v2"
}
] | 2011-04-29 | [
[
"Benzke",
"Michael",
"",
"Mainz U."
],
[
"Lee",
"Seung J.",
"",
"Weizmann Institute"
],
[
"Neubert",
"Matthias",
"",
"Mainz U."
],
[
"Paz",
"Gil",
"",
"U. Chicago"
]
] | We show that in the Standard Model the parametrically leading (by a factor 1/alpha_s) contribution to the inclusive CP asymmetry in B->X_{s,d}+gamma decays arises from a long-distance effect in the interference of the electromagnetic dipole amplitude with the amplitude for an up-quark penguin transition accompanied by soft gluon emission. This contribution is governed by a single hadronic parameter Lambda_{17}^u related to a matrix elements of a non-local operator. In view of current experimental data, a future precision measurement of the flavor-averaged CP asymmetry in B->X_s+gamma will signal the presence of new physics only if a value below -2% is found. A cleaner probe of new physics is offered by the difference of the CP asymmetries in charged versus neutral B-meson decays. |
hep-ph/0412125 | Balasubramanian Ananthanarayan | B. Ananthanarayan, P. N. Pandita | Probing SO(10) symmetry breaking patterns through sfermion mass
relations | 13 pages, latex using revtex4, contains 2 figures, replaced with
version accepted for publication | Int.J.Mod.Phys. A20 (2005) 4241 | 10.1142/S0217751X05022445 | IISc-CHEP-4/04 | hep-ph | null | We consider supersymmetric SO(10) grand unification where the unified gauge
group can break to the Standard Model gauge group through different chains. The
breaking of SO(10) necessarily involves the reduction of the rank, and
consequent generation of non-universal supersymmetry breaking scalar mass
terms. We derive squark and slepton mass relations, taking into account these
non-universal contributions to the sfermion masses, which can help distinguish
between the different chains through which the SO(10) gauge group breaks to the
Standard Model gauge group. We then study some implications of these
non-universal supersymmetry breaking scalar masses for the low energy
phenomenology.
| [
{
"created": "Thu, 9 Dec 2004 03:53:45 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Feb 2005 11:13:25 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Ananthanarayan",
"B.",
""
],
[
"Pandita",
"P. N.",
""
]
] | We consider supersymmetric SO(10) grand unification where the unified gauge group can break to the Standard Model gauge group through different chains. The breaking of SO(10) necessarily involves the reduction of the rank, and consequent generation of non-universal supersymmetry breaking scalar mass terms. We derive squark and slepton mass relations, taking into account these non-universal contributions to the sfermion masses, which can help distinguish between the different chains through which the SO(10) gauge group breaks to the Standard Model gauge group. We then study some implications of these non-universal supersymmetry breaking scalar masses for the low energy phenomenology. |
hep-ph/0306216 | Sergei Fedorov | S.M. Fedorov, Yu.A. Simonov | Pseudoscalar mesons and their radial excitations from the Effective
Chiral Lagrangian | 6 pages; v3: minor corrections, references added | JETP Lett. 78 (2003) 57-62; Pisma Zh.Eksp.Teor.Fiz. 78 (2003)
67-72 | 10.1134/1.1615529 | null | hep-ph | null | Effective Chiral Lagrangian is derived from QCD in the framework of Field
Correlator Method. It contains the effects of both confinement and chiral
symmetry breaking due to a special structure of the resulting quark mass
operator. It is shown that this Lagrangian describes light pseudoscalar mesons,
and Gell-Mann-Oakes-Renner relations for pions, eta and K mesons are
reproduced. Spectrum of radial excitations of pions and K mesons is found and
compared to experimentally known masses.
| [
{
"created": "Mon, 23 Jun 2003 15:39:28 GMT",
"version": "v1"
},
{
"created": "Tue, 24 Jun 2003 15:41:46 GMT",
"version": "v2"
},
{
"created": "Thu, 3 Jul 2003 17:22:36 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Fedorov",
"S. M.",
""
],
[
"Simonov",
"Yu. A.",
""
]
] | Effective Chiral Lagrangian is derived from QCD in the framework of Field Correlator Method. It contains the effects of both confinement and chiral symmetry breaking due to a special structure of the resulting quark mass operator. It is shown that this Lagrangian describes light pseudoscalar mesons, and Gell-Mann-Oakes-Renner relations for pions, eta and K mesons are reproduced. Spectrum of radial excitations of pions and K mesons is found and compared to experimentally known masses. |
1105.1041 | Helmut Eberl Dr. | H. Eberl, A. Bartl, B. Herrmann, K. Hidaka, W. Majerotto, W. Porod | Flavour violating up-squark decays at LHC | 4 pages, 4 figures, contribution to the proceedings of "School and
Workshops on the Standard Model and Beyond - Cosmology", Corfu, August 29 -
September 5, 2010. To appear in FdP | null | 10.1002/prop.201100061 | DESY 11-071, HEPHY-PUB 901/11 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the effect of squark generation mixing on squark production and
decays at the LHC in the Minimal Supersymmetric Standard Model (MSSM). We show
that the effect can be very large despite the very strong constraints on quark
flavour violation (QFV) from experimental data on B mesons. We find that the
two lightest up-type squarks ${\tilde u}_{1,2}$ can have large branching ratios
for the decays into $c {\tilde\chi_1^0}$ and $t {\tilde\chi_1^0}$ at the same
time, leading to QFV signals '$p p \to c \bar t\, (t \bar c)$ + missing-$E_T$ +
$X$' with a significant rate. The observation of this remarkable signature
would provide a powerful test of supersymmetric QFV at LHC. This could have a
significant impact on the search for squarks and the determination of the
underlying MSSM parameters.
| [
{
"created": "Thu, 5 May 2011 11:36:31 GMT",
"version": "v1"
}
] | 2015-05-28 | [
[
"Eberl",
"H.",
""
],
[
"Bartl",
"A.",
""
],
[
"Herrmann",
"B.",
""
],
[
"Hidaka",
"K.",
""
],
[
"Majerotto",
"W.",
""
],
[
"Porod",
"W.",
""
]
] | We study the effect of squark generation mixing on squark production and decays at the LHC in the Minimal Supersymmetric Standard Model (MSSM). We show that the effect can be very large despite the very strong constraints on quark flavour violation (QFV) from experimental data on B mesons. We find that the two lightest up-type squarks ${\tilde u}_{1,2}$ can have large branching ratios for the decays into $c {\tilde\chi_1^0}$ and $t {\tilde\chi_1^0}$ at the same time, leading to QFV signals '$p p \to c \bar t\, (t \bar c)$ + missing-$E_T$ + $X$' with a significant rate. The observation of this remarkable signature would provide a powerful test of supersymmetric QFV at LHC. This could have a significant impact on the search for squarks and the determination of the underlying MSSM parameters. |
2209.14600 | Helena Kolesova | Helena Kolesova | Attenuation of Cosmic-Ray Up-Scattered Dark Matter | Submission to SciPost Physics Proceedings: 14th International
Conference on Identification of Dark Matter | null | null | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by-nc-nd/4.0/ | GeV-scale dark matter particles with strong coupling to baryons evade the
standard direct detection limits as they are efficiently stopped in the
overburden and, consequently, are not able to reach the underground detectors.
On the other hand, it has been shown that it is possible to probe this
parameter space taking into account the flux of dark matter particles boosted
by interactions with cosmic rays. We revisit these bounds paying particular
attention to interactions of the relativistic dark matter particles in the
Earth's crust. The effects of nuclear form factors, inelastic scattering and
extra dependence of the cross section on transferred momentum (e.g., due to
presence of light mediators) are studied and are found to be crucial for
answering the question as to whether the window for GeV-scale strongly
interacting dark matter is closed or not.
| [
{
"created": "Thu, 29 Sep 2022 07:41:51 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Nov 2022 14:52:07 GMT",
"version": "v2"
}
] | 2022-11-15 | [
[
"Kolesova",
"Helena",
""
]
] | GeV-scale dark matter particles with strong coupling to baryons evade the standard direct detection limits as they are efficiently stopped in the overburden and, consequently, are not able to reach the underground detectors. On the other hand, it has been shown that it is possible to probe this parameter space taking into account the flux of dark matter particles boosted by interactions with cosmic rays. We revisit these bounds paying particular attention to interactions of the relativistic dark matter particles in the Earth's crust. The effects of nuclear form factors, inelastic scattering and extra dependence of the cross section on transferred momentum (e.g., due to presence of light mediators) are studied and are found to be crucial for answering the question as to whether the window for GeV-scale strongly interacting dark matter is closed or not. |
1607.04577 | David Latimer | Audrey K. Kvam and David C. Latimer | Optical dispersion of composite particles consisting of millicharged
constituents | arXiv admin note: text overlap with arXiv:1412.0708 | J. Phys. G: Nucl. Part. Phys. 43, 085002 (2016) | 10.1088/0954-3899/43/8/085002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Composite dark matter (DM) comprised of electrically charged constituents can
interact with the electromagnetic field via the particle's dipole moment. This
interaction results in a dispersive optical index of refraction for the DM
medium. We compute this refractive index for atomic dark matter and more
strongly bound systems, modeled via a harmonic oscillator potential. The
dispersive nature of the index will result in a time lag between high and low
energy photons simultaneously emitted from a distant astrophysical observable.
This time lag, due to matter dispersion, could confound potential claims of
Lorentz invariance violation (LIV) which can also result in such time lags. We
compare the relative size of the two effects and determine that the dispersion
due to DM is dwarfed by potential LIV effects for energies below the Planck
scale.
| [
{
"created": "Fri, 15 Jul 2016 16:51:57 GMT",
"version": "v1"
}
] | 2016-07-18 | [
[
"Kvam",
"Audrey K.",
""
],
[
"Latimer",
"David C.",
""
]
] | Composite dark matter (DM) comprised of electrically charged constituents can interact with the electromagnetic field via the particle's dipole moment. This interaction results in a dispersive optical index of refraction for the DM medium. We compute this refractive index for atomic dark matter and more strongly bound systems, modeled via a harmonic oscillator potential. The dispersive nature of the index will result in a time lag between high and low energy photons simultaneously emitted from a distant astrophysical observable. This time lag, due to matter dispersion, could confound potential claims of Lorentz invariance violation (LIV) which can also result in such time lags. We compare the relative size of the two effects and determine that the dispersion due to DM is dwarfed by potential LIV effects for energies below the Planck scale. |
1101.2936 | Jose Illana | F. del Aguila, J.I. Illana, M.D. Jenkins | Lepton flavor violation in the Simplest Little Higgs model | 41 pages, 8 figures; minor changes and one reference added, version
to appear in JHEP | JHEP 1103:080,2011 | 10.1007/JHEP03(2011)080 | CAFPE-144/10, UG-FT-274/10 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The flavor sector of Little Higgs models based on product groups, notably the
Littlest Higgs with T parity (LHT), has been extensively studied and some
amount of fine tuning was found to be required to meet the experimental
constraints. However, no such attention has been paid to other classes of
models. Here we analyze the phenomenology of flavor mixing in the lepton sector
of a simple group model, the Simplest Little Higgs (SLH). We obtain the Feynman
rules of the SLH in the 't Hooft-Feynman gauge up to the necessary order and
calculate the leading contributions to the rare processes mu -> e gamma, mu ->
eee and mu-e conversion in nuclei. We find results comparable to those of the
LHT model, because in both cases they arise at the one-loop level. These
require the flavor alignment of the Yukawa couplings of light and heavy leptons
at the per cent level or an effective scale of around 10 TeV.
| [
{
"created": "Sat, 15 Jan 2011 01:10:23 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Mar 2011 09:27:18 GMT",
"version": "v2"
}
] | 2011-03-22 | [
[
"del Aguila",
"F.",
""
],
[
"Illana",
"J. I.",
""
],
[
"Jenkins",
"M. D.",
""
]
] | The flavor sector of Little Higgs models based on product groups, notably the Littlest Higgs with T parity (LHT), has been extensively studied and some amount of fine tuning was found to be required to meet the experimental constraints. However, no such attention has been paid to other classes of models. Here we analyze the phenomenology of flavor mixing in the lepton sector of a simple group model, the Simplest Little Higgs (SLH). We obtain the Feynman rules of the SLH in the 't Hooft-Feynman gauge up to the necessary order and calculate the leading contributions to the rare processes mu -> e gamma, mu -> eee and mu-e conversion in nuclei. We find results comparable to those of the LHT model, because in both cases they arise at the one-loop level. These require the flavor alignment of the Yukawa couplings of light and heavy leptons at the per cent level or an effective scale of around 10 TeV. |
1007.4208 | Maria Elena Tejeda-Yeomans | Jorge Navarro (1,2), Angel Sanchez (3), Maria Elena Tejeda-Yeomans
(4), Alejandro Ayala (1) and Gabriella Piccinelli (5) ((1) ICN-UNAM, Mexico
D.F., (2) DF-UniAtlantico, Barranquilla, (3) IFM-UMSNH, Michoacan, (4)
DF-USON, Sonora, (5) C. Tec. Aragon UNAM, Mexico D.F.) | Symmetry restoration at finite temperature with weak magnetic fields | 29 pages, 13 figures, to appear in Phys. Rev. D. [v2]: replaced
figures 7-13 and minor corrections to typos, matches Phys. Rev. D version | Phys.Rev.D82:123007,2010 | 10.1103/PhysRevD.82.123007 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study symmetry restoration at finite temperature in the standard model
during the electroweak phase transition in the presence of a weak magnetic
field. We compute the finite temperature effective potential up to the
contribution of ring diagrams, using the broken phase degrees of freedom, and
keep track of the gauge parameter dependence of the results. We show that under
these conditions, the phase transition becomes stronger first order.
| [
{
"created": "Fri, 23 Jul 2010 20:14:42 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Dec 2010 19:20:20 GMT",
"version": "v2"
}
] | 2011-01-17 | [
[
"Navarro",
"Jorge",
""
],
[
"Sanchez",
"Angel",
""
],
[
"Tejeda-Yeomans",
"Maria Elena",
""
],
[
"Ayala",
"Alejandro",
""
],
[
"Piccinelli",
"Gabriella",
""
]
] | We study symmetry restoration at finite temperature in the standard model during the electroweak phase transition in the presence of a weak magnetic field. We compute the finite temperature effective potential up to the contribution of ring diagrams, using the broken phase degrees of freedom, and keep track of the gauge parameter dependence of the results. We show that under these conditions, the phase transition becomes stronger first order. |
1606.04053 | Norimi Yokozaki | Takeo Moroi, Tsutomu T. Yanagida and Norimi Yokozaki | Upper Bound on the Gluino Mass in Supersymmetric Models with Extra
Matters | 16 pages, 6 figures; references added | Phys.Lett. B760 (2016) 681-688 | 10.1016/j.physletb.2016.07.061 | TU-1024, UT-16-24, IPMU16-0082 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the upper bound on the gluino mass in supersymmetric models with
vector-like extra matters. In order to realize the observed Higgs mass of 125
GeV, the gluino mass is bounded from above in supersymmetric models. With the
existence of the vector-like extra matters at around TeV, we show that such an
upper bound on the gluino mass is significantly reduced compared to the case of
minimal supersymmetric standard model. This is due to the fact that radiatively
generated stop masses as well the stop trilinear coupling are enhanced in the
presence of the vector-like multiplets. In a wide range of parameter space of
the model with extra matters, the gluino is required to be lighter than $\sim
3$ TeV, which is likely to be within the reach of forthcoming LHC experiment.
| [
{
"created": "Mon, 13 Jun 2016 18:14:01 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Aug 2016 02:49:17 GMT",
"version": "v2"
}
] | 2016-08-24 | [
[
"Moroi",
"Takeo",
""
],
[
"Yanagida",
"Tsutomu T.",
""
],
[
"Yokozaki",
"Norimi",
""
]
] | We discuss the upper bound on the gluino mass in supersymmetric models with vector-like extra matters. In order to realize the observed Higgs mass of 125 GeV, the gluino mass is bounded from above in supersymmetric models. With the existence of the vector-like extra matters at around TeV, we show that such an upper bound on the gluino mass is significantly reduced compared to the case of minimal supersymmetric standard model. This is due to the fact that radiatively generated stop masses as well the stop trilinear coupling are enhanced in the presence of the vector-like multiplets. In a wide range of parameter space of the model with extra matters, the gluino is required to be lighter than $\sim 3$ TeV, which is likely to be within the reach of forthcoming LHC experiment. |
hep-ph/0403233 | Ge-Liang Song | Ge-Liang Song, Cai-Dian L\"u | Branching ratios of $B^+ \to D^{(*)+}K^{(*)0}$ decays in perturbative
QCD approach | 18 pages, 1 figure, Revtex | Phys.Rev. D70 (2004) 034006 | 10.1103/PhysRevD.70.034006 | BIHEP-TH-2004-2 | hep-ph hep-ex | null | We study the rare decays $B^+ \to D^{(*)+}K^{(*)0}$, which can occur only via
annihilation type diagrams in the standard model. We calculate all of the four
modes, $B \to PP, VP, PV, VV$, in the framework of perturbative QCD approach
and give the branching ratios of the order about $10^{-6}$.
| [
{
"created": "Mon, 22 Mar 2004 08:55:43 GMT",
"version": "v1"
},
{
"created": "Sun, 4 Apr 2004 13:12:20 GMT",
"version": "v2"
},
{
"created": "Wed, 5 May 2004 11:53:38 GMT",
"version": "v3"
},
{
"created": "Sun, 30 May 2004 13:51:51 GMT",
"version": "v4"
}
] | 2016-08-16 | [
[
"Song",
"Ge-Liang",
""
],
[
"Lü",
"Cai-Dian",
""
]
] | We study the rare decays $B^+ \to D^{(*)+}K^{(*)0}$, which can occur only via annihilation type diagrams in the standard model. We calculate all of the four modes, $B \to PP, VP, PV, VV$, in the framework of perturbative QCD approach and give the branching ratios of the order about $10^{-6}$. |
hep-ph/0201018 | Edward Witten | Edward Witten | Deconstruction, G_2 Holonomy, and Doublet-Triplet Splitting | 21 pp, additional references | null | null | null | hep-ph hep-th | null | We describe a mechanism for using discrete symmetries to solve the
doublet-triplet splitting problem of four-dimensional supersymmetric GUT's. We
present two versions of the mechanism, one via ``deconstruction,'' and one in
terms of M-theory compactification to four dimensions on a manifold of G_2
holonomy.
| [
{
"created": "Fri, 4 Jan 2002 18:14:28 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Jan 2002 00:08:04 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Witten",
"Edward",
""
]
] | We describe a mechanism for using discrete symmetries to solve the doublet-triplet splitting problem of four-dimensional supersymmetric GUT's. We present two versions of the mechanism, one via ``deconstruction,'' and one in terms of M-theory compactification to four dimensions on a manifold of G_2 holonomy. |
hep-ph/0211351 | Andrey Grozin | A. G. Grozin | Progress in multiloop calculations | Section summary talk at ACAT'2002 (Moscow) | Nucl.Instrum.Meth. A502 (2003) 815-817 | 10.1016/S0168-9002(03)00608-9 | null | hep-ph | null | I briefly summarize the talks on calculation of multiloop Feynman diagrams
presented at ACAT'2002 (Moscow University).
| [
{
"created": "Fri, 22 Nov 2002 10:38:58 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Grozin",
"A. G.",
""
]
] | I briefly summarize the talks on calculation of multiloop Feynman diagrams presented at ACAT'2002 (Moscow University). |
0807.4114 | Asim Ali Malik | A.A. Malik and I.S. Satsunkevich | Production of $(\tau^+\tau^-)_b$ in electron positron collisions | 5 pages, submitted to Int. Jour. Mod. Phys. A | null | 10.1142/S0217751X09046813 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | $(\tau^+\tau^-)_b$ is an atom of simple hydrogenlike structure similar to
positronium $(e^+e^-)_b$ and $(\mu^+\mu^-)_b$. In this paper energy levels and
decay widths of different decay channels of $(\tau^+\tau^-)_b$ are given. Cross
section of production of this atomic system in $e^+e^-$ annihilation taking
into account radiative corrections is calculated. According to our estimates
886 $(\tau^+\tau^-)_b$ atoms may be produced at BEPCII and 29
$(\tau^+\tau^-)_b$ atoms are produced at VEPP-4M under the present experimental
conditions.
| [
{
"created": "Fri, 25 Jul 2008 15:17:09 GMT",
"version": "v1"
}
] | 2015-05-13 | [
[
"Malik",
"A. A.",
""
],
[
"Satsunkevich",
"I. S.",
""
]
] | $(\tau^+\tau^-)_b$ is an atom of simple hydrogenlike structure similar to positronium $(e^+e^-)_b$ and $(\mu^+\mu^-)_b$. In this paper energy levels and decay widths of different decay channels of $(\tau^+\tau^-)_b$ are given. Cross section of production of this atomic system in $e^+e^-$ annihilation taking into account radiative corrections is calculated. According to our estimates 886 $(\tau^+\tau^-)_b$ atoms may be produced at BEPCII and 29 $(\tau^+\tau^-)_b$ atoms are produced at VEPP-4M under the present experimental conditions. |
hep-ph/0107115 | Bojan Golli | Bojan Golli | Soliton Formation in Chiral Quark Models | 11 pages, 6 Postscript figures, plain LaTeX, talk presented at the
Mini-Workshop on ``Hadrons as Solitons'', Bled, Slovenia, 6-17 July 1999 | null | null | null | hep-ph | null | We describe how the non-local regularization can be implemented in the
calculation of solitons in the Nambu Jona-Lasinio model as well as in the
equivalent linear sigma-model. We investigate different forms of regulators and
show that the 3-momentum cut-off leads to serious conceptual difficulties.
| [
{
"created": "Tue, 10 Jul 2001 19:26:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Golli",
"Bojan",
""
]
] | We describe how the non-local regularization can be implemented in the calculation of solitons in the Nambu Jona-Lasinio model as well as in the equivalent linear sigma-model. We investigate different forms of regulators and show that the 3-momentum cut-off leads to serious conceptual difficulties. |
1505.05638 | Thomas D. Cohen | Thomas D. Cohen, Brian Mc Peak and Bendeguz Offertaler | Nucleon-Antinucleon Annhiliation at Large Nc | Minor typos fixed in new version | Phys. Rev. C 92, 015204 (2015) | 10.1103/PhysRevC.92.015204 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by-nc-sa/3.0/ | Nucleon-antinucleon annihilation in the large $N_c$ limit of QCD in the
Witten regime of fixed velocity is considered with a focus on the spin and
isospin dependence of the annihilation cross-section. In general, time-reversal
and isospin invariance restricts the annihilation cross-section to depend on 6
independent energy-dependent terms. At large $N_c$, a spin-flavor symmetry
emerges in the theory that acts to further restrict the dependence of the
annihilation cross-section to three of these terms; the other terms amount to
$1/N_c$ corrections. Assuming dominance of the leading order terms, several
identities are derived that relate annihilation in different spin-isospin
channels. A key prediction is that for unpolarized nucleons in Witten
kinematics, the proton-antiproton annihilation cross-section should be equal to
the proton-antineutron annihilation cross-section up to corrections of relative
order $1/N_c$. Unpolarized nucleon-antinucleon annihilation data appears to be
consistent with this expectation.
| [
{
"created": "Thu, 21 May 2015 08:04:03 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Jun 2015 14:32:36 GMT",
"version": "v2"
}
] | 2015-07-22 | [
[
"Cohen",
"Thomas D.",
""
],
[
"Peak",
"Brian Mc",
""
],
[
"Offertaler",
"Bendeguz",
""
]
] | Nucleon-antinucleon annihilation in the large $N_c$ limit of QCD in the Witten regime of fixed velocity is considered with a focus on the spin and isospin dependence of the annihilation cross-section. In general, time-reversal and isospin invariance restricts the annihilation cross-section to depend on 6 independent energy-dependent terms. At large $N_c$, a spin-flavor symmetry emerges in the theory that acts to further restrict the dependence of the annihilation cross-section to three of these terms; the other terms amount to $1/N_c$ corrections. Assuming dominance of the leading order terms, several identities are derived that relate annihilation in different spin-isospin channels. A key prediction is that for unpolarized nucleons in Witten kinematics, the proton-antiproton annihilation cross-section should be equal to the proton-antineutron annihilation cross-section up to corrections of relative order $1/N_c$. Unpolarized nucleon-antinucleon annihilation data appears to be consistent with this expectation. |
1804.02656 | Kazem Azizi | T. M. Aliev, K. Azizi, H. Sundu | Analysis of the structure of $\Xi(1690)$ through its decays | 9 Pages, 5 Figures and 3 Tables. Some typos have been corrected and
some new references have been added | null | 10.1140/epjc/s10052-018-5888-8 | null | hep-ph hep-ex hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The mass and pole residue of the first orbitally and radially excited $ \Xi$
state as well as the ground state residue are calculated by means of the
two-point QCD sum rules. Using the obtained results for the spectroscopic
parameters, the strong coupling constants relevant to the decays
$\Xi(1690)\rightarrow \Sigma K$ and $\Xi(1690) \rightarrow \Lambda K$ are
calculated within the light-cone QCD sum rules and width of these decay
channels are estimated. The obtained results for the mass of $ \widetilde{\Xi}
$ and ratio of the $Br\Big(\widetilde{\Xi}\rightarrow \Sigma
K\Big)/Br\Big(\widetilde{\Xi}\rightarrow \Lambda K\Big)$, with $
\widetilde{\Xi} $ representing the orbitally excited state in $ \Xi $ channel,
are in nice agreement with the experimental data of the Belle Collaboration.
This allows us to conclude that the $\Xi(1690)$ state, most probably, has
negative parity.
| [
{
"created": "Sun, 8 Apr 2018 09:03:53 GMT",
"version": "v1"
},
{
"created": "Sun, 22 Apr 2018 11:17:25 GMT",
"version": "v2"
}
] | 2018-06-13 | [
[
"Aliev",
"T. M.",
""
],
[
"Azizi",
"K.",
""
],
[
"Sundu",
"H.",
""
]
] | The mass and pole residue of the first orbitally and radially excited $ \Xi$ state as well as the ground state residue are calculated by means of the two-point QCD sum rules. Using the obtained results for the spectroscopic parameters, the strong coupling constants relevant to the decays $\Xi(1690)\rightarrow \Sigma K$ and $\Xi(1690) \rightarrow \Lambda K$ are calculated within the light-cone QCD sum rules and width of these decay channels are estimated. The obtained results for the mass of $ \widetilde{\Xi} $ and ratio of the $Br\Big(\widetilde{\Xi}\rightarrow \Sigma K\Big)/Br\Big(\widetilde{\Xi}\rightarrow \Lambda K\Big)$, with $ \widetilde{\Xi} $ representing the orbitally excited state in $ \Xi $ channel, are in nice agreement with the experimental data of the Belle Collaboration. This allows us to conclude that the $\Xi(1690)$ state, most probably, has negative parity. |
hep-ph/0510004 | Hiroyuki Kawamura | H.Kawamura, J.Kodaira, H.Shimizu and K.Tanaka | Q_T Resummation in Transversely Polarized Drell-Yan Process | 4 pages, 1 figure, contribution to proceedings of International
Conference on QCD and Hadronic Physics, Beijing, June 16-20, 2005 | Int.J.Mod.Phys. A21 (2006) 918-922 | 10.1016/j.nuclphysbps.2006.03.047 | null | hep-ph | null | We calculate QCD corrections to transversely polarized Drell-Yan process at a
measured $Q_T$ of the produced lepton pair in the dimensional regularization
scheme. The $Q_T$ distribution is discussed resumming soft gluon effects
relevant for small $Q_T$.
| [
{
"created": "Sat, 1 Oct 2005 09:30:24 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Kawamura",
"H.",
""
],
[
"Kodaira",
"J.",
""
],
[
"Shimizu",
"H.",
""
],
[
"Tanaka",
"K.",
""
]
] | We calculate QCD corrections to transversely polarized Drell-Yan process at a measured $Q_T$ of the produced lepton pair in the dimensional regularization scheme. The $Q_T$ distribution is discussed resumming soft gluon effects relevant for small $Q_T$. |
hep-ph/9705276 | John Collins | J.C. Collins | QCD and Hadronic Interactions: Summary talk for Moriond 97 | 8 pages LaTeX. To appear in Proceedings of 32nd Rencontre de Moriond,
QCD and High-Energy Hadronic Interaction, March 1997 | null | null | null | hep-ph | null | This talk covers a selection of topics that were discussed at this meeting in
the non-heavy-ion sessions: (a) The high $Q^{2}$ events at HERA and their
theoretical interpretation. (b) The issues of how well we know the predictions
of QCD, with a particular emphasis on resummation. (c) Anomalies in jet
production in association with $W$ bosons at the Tevatron and in dijet
production in deep-inelastic scattering. (d) Diffractive hard scattering.
| [
{
"created": "Fri, 9 May 1997 11:59:14 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Collins",
"J. C.",
""
]
] | This talk covers a selection of topics that were discussed at this meeting in the non-heavy-ion sessions: (a) The high $Q^{2}$ events at HERA and their theoretical interpretation. (b) The issues of how well we know the predictions of QCD, with a particular emphasis on resummation. (c) Anomalies in jet production in association with $W$ bosons at the Tevatron and in dijet production in deep-inelastic scattering. (d) Diffractive hard scattering. |
1707.01885 | Ismail Zahed | Edward Shuryak and Ismail Zahed | Regimes of the Pomeron and its Intrinsic Entropy | 14 pages, 6 figures | null | 10.1016/j.aop.2018.06.008 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We suggest that the perturbative and non-perturbative descriptions of the
Pomeron can be viewed as complementary descriptions of different phases in the
Pomeron phase diagram, with a phase boundary where the proper description of
the produced systems are "string balls". Their intrinsic entropy is calculated
and turned out to be the same, as the recently reported perturbative
entanglement entropy. The distribution of large multiplicities stemming from
the string balls is also wide, with its moments close to those reported for
hadrons in $pp$ collisions at the LHC. At low-x, the quantum string is so
entangled that sufficiently weak string self-attraction can cause it to turn to
a string ball dual to a black hole. We suggest that low-x saturation occurs
when the density of wee-strings reaches the Bekenstein bound, with a proton
size that freezes with increasing rapidity. Some of these observations maybe
checked at the future eIC.
| [
{
"created": "Thu, 6 Jul 2017 17:41:05 GMT",
"version": "v1"
}
] | 2018-08-01 | [
[
"Shuryak",
"Edward",
""
],
[
"Zahed",
"Ismail",
""
]
] | We suggest that the perturbative and non-perturbative descriptions of the Pomeron can be viewed as complementary descriptions of different phases in the Pomeron phase diagram, with a phase boundary where the proper description of the produced systems are "string balls". Their intrinsic entropy is calculated and turned out to be the same, as the recently reported perturbative entanglement entropy. The distribution of large multiplicities stemming from the string balls is also wide, with its moments close to those reported for hadrons in $pp$ collisions at the LHC. At low-x, the quantum string is so entangled that sufficiently weak string self-attraction can cause it to turn to a string ball dual to a black hole. We suggest that low-x saturation occurs when the density of wee-strings reaches the Bekenstein bound, with a proton size that freezes with increasing rapidity. Some of these observations maybe checked at the future eIC. |
hep-ph/9710285 | L. Maharana | A. K. Giri, L. Maharana and R. Mohanta | Two body non-leptonic $\Lambda_b$ decays in the large $N_c$ limit | null | Pramana 49 (1997) 645-651 | 10.1007/BF02848338 | null | hep-ph | null | The two body non-leptonic $\Lambda_b$ decays are analyzed in the HQET with
factorization approximation and large $N_c$ limit. In this limit, $\Lambda_b$
and $\Lambda_c$ baryons can be treated as the bound states of chiral soliton
and heavy meson, and consequently the Isgur-Wise function comes out in a
straight forward manner. The results obtained remain well below their
previously predicted upper limit.
| [
{
"created": "Wed, 8 Oct 1997 13:18:52 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Giri",
"A. K.",
""
],
[
"Maharana",
"L.",
""
],
[
"Mohanta",
"R.",
""
]
] | The two body non-leptonic $\Lambda_b$ decays are analyzed in the HQET with factorization approximation and large $N_c$ limit. In this limit, $\Lambda_b$ and $\Lambda_c$ baryons can be treated as the bound states of chiral soliton and heavy meson, and consequently the Isgur-Wise function comes out in a straight forward manner. The results obtained remain well below their previously predicted upper limit. |
hep-ph/0701104 | Alessandro Strumia | Vyacheslav S. Rychkov, Alessandro Strumia | Thermal production of gravitinos | 33 pages (long appendices), 12 figures. Final version to appear on
PRD | Phys.Rev.D75:075011,2007 | 10.1103/PhysRevD.75.075011 | IFUP-TH/07-1 | hep-ph hep-th | null | We reconsider thermal production of gravitinos in the early universe, adding
to previously considered 2 -> 2 gauge scatterings: a) production via 1 -> 2
decays, allowed by thermal masses; b) the effect of the top Yukawa coupling; c)
a proper treatment of the reheating process. Our final result behaves
physically (larger couplings give a larger rate) and is twice larger than
previous results, implying e.g. a twice stronger constraint on the reheating
temperature. Accessory results about (supersymmetric) theories at finite
temperature and gravitino couplings might have some interest.
| [
{
"created": "Sun, 14 Jan 2007 11:28:09 GMT",
"version": "v1"
},
{
"created": "Thu, 12 Apr 2007 18:06:25 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Rychkov",
"Vyacheslav S.",
""
],
[
"Strumia",
"Alessandro",
""
]
] | We reconsider thermal production of gravitinos in the early universe, adding to previously considered 2 -> 2 gauge scatterings: a) production via 1 -> 2 decays, allowed by thermal masses; b) the effect of the top Yukawa coupling; c) a proper treatment of the reheating process. Our final result behaves physically (larger couplings give a larger rate) and is twice larger than previous results, implying e.g. a twice stronger constraint on the reheating temperature. Accessory results about (supersymmetric) theories at finite temperature and gravitino couplings might have some interest. |
1508.06844 | Yu-Feng Zhou | Hong-Bo Jin, Yue-Liang Wu, Yu-Feng Zhou | Implications of the first AMS-02 antiproton data for dark matter | Talk given at the International Conference on Gravitation and
Cosmology, May 5-8, 2015, Beijing, to appear in the proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The implications of the first AMS-02 $\bar p/p$ data for the propagation of
cosmic rays and the properties of dark matter (DM) are discussed. Using various
diffusive re-acceleration (DR) propagation models, one can derive very
conservative upper limits on the DM annihilation cross sections. The limits
turned out to be compatible with that from the Ferm-LAT gamma-ray data on the
dwarf spheroidal satellite galaxies. The flattening of the $\bar p/p$ spectrum
above $\sim 100$~GeV in the current data still leaves some room for TeV scale
DM particles. More antiproton data at high kinetic energies are needed to
constrain the properties of the DM particles.
| [
{
"created": "Thu, 27 Aug 2015 13:05:44 GMT",
"version": "v1"
}
] | 2015-08-28 | [
[
"Jin",
"Hong-Bo",
""
],
[
"Wu",
"Yue-Liang",
""
],
[
"Zhou",
"Yu-Feng",
""
]
] | The implications of the first AMS-02 $\bar p/p$ data for the propagation of cosmic rays and the properties of dark matter (DM) are discussed. Using various diffusive re-acceleration (DR) propagation models, one can derive very conservative upper limits on the DM annihilation cross sections. The limits turned out to be compatible with that from the Ferm-LAT gamma-ray data on the dwarf spheroidal satellite galaxies. The flattening of the $\bar p/p$ spectrum above $\sim 100$~GeV in the current data still leaves some room for TeV scale DM particles. More antiproton data at high kinetic energies are needed to constrain the properties of the DM particles. |
0806.4065 | Tomohiro Matsuda | Tomohiro Matsuda | Modulated Inflation (@SUSY08) | talk given at susy08 | AIP Conf.Proc.1078:521-523,2009 | 10.1063/1.3052015 | null | hep-ph astro-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider cosmological perturbations caused by modulated inflaton velocity.
During inflation, the inflaton motion is damped and the velocity is determined
by the parameters such as couplings or masses that may depend on light
fields(moduli). The number of e-foldings is different in different patches if
there are spatial fluctuations of such parameters. Based on this simple idea,
we consider ``modulated inflation'' in which the curvature perturbation is
generated by the fluctuation of the inflaton velocity. This talk is based on
our recent papers.
| [
{
"created": "Wed, 25 Jun 2008 10:47:26 GMT",
"version": "v1"
}
] | 2009-02-02 | [
[
"Matsuda",
"Tomohiro",
""
]
] | We consider cosmological perturbations caused by modulated inflaton velocity. During inflation, the inflaton motion is damped and the velocity is determined by the parameters such as couplings or masses that may depend on light fields(moduli). The number of e-foldings is different in different patches if there are spatial fluctuations of such parameters. Based on this simple idea, we consider ``modulated inflation'' in which the curvature perturbation is generated by the fluctuation of the inflaton velocity. This talk is based on our recent papers. |
1104.3996 | HongWei Ke | Hong-Wei Ke and Xue-Qian Li | Vertex functions for d-wave mesons in the light-front approach | 12 pages, 2 figures, some typos corrected and more discussions added.
Accepted by EPJC | Eur. Phys. J. C (2011) 71:1776 | 10.1140/epjc/s10052-011-1776-1 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | While the light-front quark model (LFQM) is employed to calculate hadronic
transition matrix elements, the vertex functions must be pre-determined. In
this work we derive the vertex functions for all d-wave states in this model.
Especially, since both of $^3D_1$ and $^3S_1$ are $1^{--}$ mesons, the Lorentz
structures of their vertex functions are the same. Thus when one needs to study
the processes where $^3D_1$ is involved, all the corresponding formulas for
$^3S_1$ states can be directly applied, only the coefficient of the vertex
function should be replaced by that for $^3D_1$. The results would be useful
for studying the newly observed resonances which are supposed to be d-wave
mesons and furthermore the possible 2S-1D mixing in $\psi'$ with the LFQM.
| [
{
"created": "Wed, 20 Apr 2011 11:05:58 GMT",
"version": "v1"
},
{
"created": "Fri, 19 Aug 2011 13:27:50 GMT",
"version": "v2"
},
{
"created": "Tue, 4 Oct 2011 05:16:23 GMT",
"version": "v3"
}
] | 2011-10-14 | [
[
"Ke",
"Hong-Wei",
""
],
[
"Li",
"Xue-Qian",
""
]
] | While the light-front quark model (LFQM) is employed to calculate hadronic transition matrix elements, the vertex functions must be pre-determined. In this work we derive the vertex functions for all d-wave states in this model. Especially, since both of $^3D_1$ and $^3S_1$ are $1^{--}$ mesons, the Lorentz structures of their vertex functions are the same. Thus when one needs to study the processes where $^3D_1$ is involved, all the corresponding formulas for $^3S_1$ states can be directly applied, only the coefficient of the vertex function should be replaced by that for $^3D_1$. The results would be useful for studying the newly observed resonances which are supposed to be d-wave mesons and furthermore the possible 2S-1D mixing in $\psi'$ with the LFQM. |
1102.0691 | Amy Connolly | Amy Connolly, Robert S. Thorne, David Waters | Calculation of High Energy Neutrino-Nucleon Cross Sections and
Uncertainties Using the MSTW Parton Distribution Functions and Implications
for Future Experiments | 20 pages, 13 figures, 5 tables, published in Phys.Rev.D. This version
fixes a typo in Equation 16 of the publication. Also since version v1, the
following changes are in v2 and also in the published version: tables with cs
values, parametrization of the y distribution at low-y improved, the
discussions on likelihood and also earth absorption are expanded, added a
needed minus sign in Eq. 17 of v1 | Phys.Rev.D83:113009,2011 | 10.1103/PhysRevD.83.113009 | null | hep-ph astro-ph.IM | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a new calculation of the cross sections for charged current (CC)
and neutral current (NC) $\nu N$ and $\bar{\nu} N$ interactions in the neutrino
energy range $10^{4}<E_{\nu}<10^{12}$ GeV using the most recent MSTW parton
distribution functions (PDFs), MSTW 2008. We also present the associated
uncertainties propagated from the PDFs, as well as parametrizations of the
cross section central values, their uncertainty bounds, and the inelasticity
distributions for ease of use in Monte Carlo simulations. For the latter we
only provide parametrizations for energies above $10^7$ GeV. Finally, we assess
the feasibility of future neutrino experiments to constrain the $\nu N$ cross
section in the ultra-high energy (UHE) regime using a technique that is
independent of the flux spectrum of incident neutrinos. A significant deviation
from the predicted Standard Model cross sections could be an indication of new
physics, such as extra space-time dimensions, and we present expected
constraints on such models as a function of the number of events observed in a
future subterranean neutrino detector.
| [
{
"created": "Thu, 3 Feb 2011 14:16:48 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Aug 2011 03:40:44 GMT",
"version": "v2"
}
] | 2011-08-17 | [
[
"Connolly",
"Amy",
""
],
[
"Thorne",
"Robert S.",
""
],
[
"Waters",
"David",
""
]
] | We present a new calculation of the cross sections for charged current (CC) and neutral current (NC) $\nu N$ and $\bar{\nu} N$ interactions in the neutrino energy range $10^{4}<E_{\nu}<10^{12}$ GeV using the most recent MSTW parton distribution functions (PDFs), MSTW 2008. We also present the associated uncertainties propagated from the PDFs, as well as parametrizations of the cross section central values, their uncertainty bounds, and the inelasticity distributions for ease of use in Monte Carlo simulations. For the latter we only provide parametrizations for energies above $10^7$ GeV. Finally, we assess the feasibility of future neutrino experiments to constrain the $\nu N$ cross section in the ultra-high energy (UHE) regime using a technique that is independent of the flux spectrum of incident neutrinos. A significant deviation from the predicted Standard Model cross sections could be an indication of new physics, such as extra space-time dimensions, and we present expected constraints on such models as a function of the number of events observed in a future subterranean neutrino detector. |
0805.2289 | Kazuhiro Tanaka | Yuji Koike (1), Kazuhiro Tanaka (2), Shinsuke Yoshida (1) ((1) Niigata
Univ., (2) Juntendo Univ.) | Drell-Yan double-spin asymmetry A_{LT} in polarized p\bar{p} collisions:
Wandzura-Wilczek contribution | 12 pages, 4 figures, minor modifications, typos corrected; version to
appear in PLB | Phys.Lett.B668:286-292,2008 | 10.1016/j.physletb.2008.08.049 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The longitudinal-transverse spin asymmetry A_{LT} in the polarized Drell-Yan
process depends on the twist-3 spin-dependent distributions of nucleon. In
addition to the contributions expressed as matrix element of the twist-3
operators, these distributions contain the so-called Wandzura-Wilczek part,
which is completely determined by a certain integral of the twist-2
spin-dependent parton distributions. We demonstrate that the recently obtained
empirical information on the transversity distribution allows a realistic
estimate of the Wandzura-Wilczek contribution to A_{LT} for the case of
polarized proton-antiproton collisions. In particular, our results in the
Wandzura-Wilczek approximation indicate that rather large A_{LT} can be
observed in the proposed spin experiments at GSI, and its behavior as a
function of dilepton mass obeys novel pattern, compared with the other
double-spin asymmetries A_{TT} and A_{LL}. Our results provide a guide for
testing a signal of effects originating from the twist-3 operators associated
with quark-gluon correlation.
| [
{
"created": "Thu, 15 May 2008 12:51:39 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Aug 2008 11:55:46 GMT",
"version": "v2"
},
{
"created": "Fri, 5 Sep 2008 13:15:06 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Koike",
"Yuji",
""
],
[
"Tanaka",
"Kazuhiro",
""
],
[
"Yoshida",
"Shinsuke",
""
]
] | The longitudinal-transverse spin asymmetry A_{LT} in the polarized Drell-Yan process depends on the twist-3 spin-dependent distributions of nucleon. In addition to the contributions expressed as matrix element of the twist-3 operators, these distributions contain the so-called Wandzura-Wilczek part, which is completely determined by a certain integral of the twist-2 spin-dependent parton distributions. We demonstrate that the recently obtained empirical information on the transversity distribution allows a realistic estimate of the Wandzura-Wilczek contribution to A_{LT} for the case of polarized proton-antiproton collisions. In particular, our results in the Wandzura-Wilczek approximation indicate that rather large A_{LT} can be observed in the proposed spin experiments at GSI, and its behavior as a function of dilepton mass obeys novel pattern, compared with the other double-spin asymmetries A_{TT} and A_{LL}. Our results provide a guide for testing a signal of effects originating from the twist-3 operators associated with quark-gluon correlation. |
0806.4126 | Andre Utermann | Andre Utermann | About Geometric Scaling and Small-x Evolution at RHIC and LHC | 4 pages, 2 figures, contributed to the Proceedings of DIS2008 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that the whole range of RHIC data for hadron production in d-Au
collisions is compatible with geometric scaling. To establish the scaling
violations expected from small-x evolution a larger kinematic range in
transverse momentum and rapidity would be needed. We point out that the
fall-off of the p_t distribution of produced hadrons at large p_t is a
sensitive probe of small-x evolution especially at the LHC.
| [
{
"created": "Wed, 25 Jun 2008 15:21:42 GMT",
"version": "v1"
}
] | 2008-06-26 | [
[
"Utermann",
"Andre",
""
]
] | We show that the whole range of RHIC data for hadron production in d-Au collisions is compatible with geometric scaling. To establish the scaling violations expected from small-x evolution a larger kinematic range in transverse momentum and rapidity would be needed. We point out that the fall-off of the p_t distribution of produced hadrons at large p_t is a sensitive probe of small-x evolution especially at the LHC. |
0812.0716 | Fulvia De Fazio | Fulvia De Fazio | Radiative transitions of heavy quarkonium states | RevTex, 9 pages, 5 figures. Eqs. (2.11) and (4.3) corrected | Phys.Rev.D79:054015,2009; Erratum-ibid.D83:099901,2011 | 10.1103/PhysRevD.79.054015 10.1103/PhysRevD.83.099901 | BARI-TH/08-600 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study radiative decays of heavy $Q{\bar Q}$ states, both for $Q=c$ and
$Q=b$, using an effective Lagrangian approach which exploits spin symmetry for
such states. We use existing data on radiative quarkonium transitions to
predict some unmeasured decay rates. We also discuss how these modes can be
useful to understand the structure of X(3872).
| [
{
"created": "Wed, 3 Dec 2008 13:45:32 GMT",
"version": "v1"
},
{
"created": "Mon, 2 May 2011 09:59:24 GMT",
"version": "v2"
}
] | 2011-05-19 | [
[
"De Fazio",
"Fulvia",
""
]
] | We study radiative decays of heavy $Q{\bar Q}$ states, both for $Q=c$ and $Q=b$, using an effective Lagrangian approach which exploits spin symmetry for such states. We use existing data on radiative quarkonium transitions to predict some unmeasured decay rates. We also discuss how these modes can be useful to understand the structure of X(3872). |
hep-ph/0405122 | Ulrich Haisch | U. Haisch | Recent Theoretical Developments in B -> X_s l^+ l^- Decays | 7 pages, 1 figure; Talk given at XXIXth Rencontres de Moriond
Electroweak Interactions and Unified Theories, La Thuile, Aosta Valley,
Italy, March 21-28, 2004 | null | null | FERMILAB-Conf-04/063-T | hep-ph | null | We present a concise review of the theoretical status of the rare
semileptonic B -> X_s l^+ l^- decays in the standard model. Particular
attention is thereby devoted to the recent theoretical progress concerning, on
the one hand the next-to-next-to-leading order QCD calculation and, on the
other hand the analysis of phenomenological important subleading electroweak
effects.
| [
{
"created": "Thu, 13 May 2004 15:41:50 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Haisch",
"U.",
""
]
] | We present a concise review of the theoretical status of the rare semileptonic B -> X_s l^+ l^- decays in the standard model. Particular attention is thereby devoted to the recent theoretical progress concerning, on the one hand the next-to-next-to-leading order QCD calculation and, on the other hand the analysis of phenomenological important subleading electroweak effects. |
0801.0095 | Stanislaw Tatur | Stanislaw Tatur and Jan Bartelski | Mass matrices for quarks and leptons in triangular form | Latex, 20 pages, no figures, extended and modified version to be
published in Acta Phys. Pol. B | Acta Phys.Polon.B39:2903-2920,2008 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We assume that all quark and lepton mass matrices have upper triangular form.
Using all available experimental data on quark and lepton masses and mixing
angles we make a fit in which we determine mass matrices elements. There are
too many free parameters and our solutions are not uniqe. We look for solutions
with small non diagonal mixing matrix elements. In order to reduce the number
of free parameters we assume that the matrix element $(M)_{13}$ vanishes in
\underline{all} mass matrices. Such universal assumption was drown from
considering different numerical solutions. The lepton sector, due to large
mixing angles and very small errors for charged lepton masses, is more
restrictive then quark sector. We present the solution in this case. The
absolute values of neutrino masses are not fixed. The another possibility of
reducing number of free parameters was considered by us before. With the
additional assumption motivated by SU(5) symmetry which connects mixing in
right handed down quarks with left handed charged leptons we get a solution in
which observed Cabibbo-Kobayashi-Maskawa mixing for quarks comes mainly from
non diagonal terms in up quark mass matrix. From the fit we get also
predictions for neutrino masses.
| [
{
"created": "Sat, 29 Dec 2007 22:09:54 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Feb 2008 16:18:51 GMT",
"version": "v2"
},
{
"created": "Thu, 4 Sep 2008 14:10:16 GMT",
"version": "v3"
}
] | 2008-12-19 | [
[
"Tatur",
"Stanislaw",
""
],
[
"Bartelski",
"Jan",
""
]
] | We assume that all quark and lepton mass matrices have upper triangular form. Using all available experimental data on quark and lepton masses and mixing angles we make a fit in which we determine mass matrices elements. There are too many free parameters and our solutions are not uniqe. We look for solutions with small non diagonal mixing matrix elements. In order to reduce the number of free parameters we assume that the matrix element $(M)_{13}$ vanishes in \underline{all} mass matrices. Such universal assumption was drown from considering different numerical solutions. The lepton sector, due to large mixing angles and very small errors for charged lepton masses, is more restrictive then quark sector. We present the solution in this case. The absolute values of neutrino masses are not fixed. The another possibility of reducing number of free parameters was considered by us before. With the additional assumption motivated by SU(5) symmetry which connects mixing in right handed down quarks with left handed charged leptons we get a solution in which observed Cabibbo-Kobayashi-Maskawa mixing for quarks comes mainly from non diagonal terms in up quark mass matrix. From the fit we get also predictions for neutrino masses. |
0911.2662 | Martin Hentschinski | G. Chachamis, M. Hentschinski, A. Sabio Vera, C. Salas | Exclusive central production of heavy quarks at the LHC | 10 pages, 1 figure | null | null | IFT-UAM/CSIC-09-56 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the exclusive production of heavy flavors at central rapidities in
hadron-hadron collisions within the kT factorisation formalism. Since this
involves regions of small Bjorken x in the unintegrated gluon densities, we
include the next-to-leading order BFKL contributions working directly in
transverse momentum representation. Our results are presented in a form
suitable for Monte Carlo implementation.
| [
{
"created": "Fri, 13 Nov 2009 17:43:57 GMT",
"version": "v1"
}
] | 2009-11-16 | [
[
"Chachamis",
"G.",
""
],
[
"Hentschinski",
"M.",
""
],
[
"Vera",
"A. Sabio",
""
],
[
"Salas",
"C.",
""
]
] | We study the exclusive production of heavy flavors at central rapidities in hadron-hadron collisions within the kT factorisation formalism. Since this involves regions of small Bjorken x in the unintegrated gluon densities, we include the next-to-leading order BFKL contributions working directly in transverse momentum representation. Our results are presented in a form suitable for Monte Carlo implementation. |
hep-ph/9606301 | Johan Bijnens | J. Bijnens and U.-G. Mei{\ss}ner | The Standard Model at Low Energies | 53 pages, LaTeX, miniproceedings (see abstract) | null | null | ECT*-96-010, TK 96 18, NORDITA 96/35 N,P | hep-ph nucl-th | null | These are short proceedings of the workshop on ``The Standard Model at Low
Energies'' held at ECT* in Trento, Italy, from April 29 to May 10, 1996. The
workshop concentrated on Chiral Perturbation Theory in its various settings.
Included are a one page contribution with references per speaker and a listing
of some review papers of relevance to the field.
| [
{
"created": "Tue, 11 Jun 1996 12:30:08 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bijnens",
"J.",
""
],
[
"Meißner",
"U. -G.",
""
]
] | These are short proceedings of the workshop on ``The Standard Model at Low Energies'' held at ECT* in Trento, Italy, from April 29 to May 10, 1996. The workshop concentrated on Chiral Perturbation Theory in its various settings. Included are a one page contribution with references per speaker and a listing of some review papers of relevance to the field. |
1308.0413 | Hsiang-nan Li | Hsiang-nan Li | Resummation with Wilson lines off the light cone | 18 pages, 13 figures; invited review article to be published by
Physics of Elementary Particles and Atomic Nuclei | null | 10.1134/S106377961404011X | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I review the resummation formalism for organizing large logarithms in
perturbative expansion of collinear subprocesses through the variation of
Wilson lines off the light cone. A master equation is derived, which involves
the evolution kernel resulting from this variation. It is then demonstrated
that all the known single- and double-logarithm summations for a parton
distribution function or a transverse-momentum-dependentparton distribution can
be reproduced from the master equation by applying appropriate soft-gluon
approximations to the evolution kernel. Moreover, jet substructures,
information which is crucial for particle identification at the Large Hadron
Collider and usually acquired from event generators, can also be calculated in
this formalism.
| [
{
"created": "Fri, 2 Aug 2013 05:42:43 GMT",
"version": "v1"
}
] | 2015-06-16 | [
[
"Li",
"Hsiang-nan",
""
]
] | I review the resummation formalism for organizing large logarithms in perturbative expansion of collinear subprocesses through the variation of Wilson lines off the light cone. A master equation is derived, which involves the evolution kernel resulting from this variation. It is then demonstrated that all the known single- and double-logarithm summations for a parton distribution function or a transverse-momentum-dependentparton distribution can be reproduced from the master equation by applying appropriate soft-gluon approximations to the evolution kernel. Moreover, jet substructures, information which is crucial for particle identification at the Large Hadron Collider and usually acquired from event generators, can also be calculated in this formalism. |
hep-ph/0607126 | Yoshitaka Hatta | Yoshitaka Hatta | CGC formalism with two sources | Improved derivation of light-cone gauge source terms, version to
appear in Nucl. Phys. A | Nucl.Phys.A781:104-121,2007 | 10.1016/j.nuclphysa.2006.10.076 | RBRC-605 | hep-ph | null | In this work we extend the JIMWLK formalism to the two-source problem. The
S-matrix for the forward scattering can be written in a double functional
integral representation which involves the usual functional integral for the
gluon field and the spin path integral for the external color sources.
Modifications needed in the light-cone gauge are discussed. Using our source
term we compute the produced gluon field and discuss the duality of the high
energy evolution kernel in the pA collision.
| [
{
"created": "Tue, 11 Jul 2006 18:32:40 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Sep 2006 17:44:33 GMT",
"version": "v2"
},
{
"created": "Tue, 24 Oct 2006 08:55:34 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Hatta",
"Yoshitaka",
""
]
] | In this work we extend the JIMWLK formalism to the two-source problem. The S-matrix for the forward scattering can be written in a double functional integral representation which involves the usual functional integral for the gluon field and the spin path integral for the external color sources. Modifications needed in the light-cone gauge are discussed. Using our source term we compute the produced gluon field and discuss the duality of the high energy evolution kernel in the pA collision. |
hep-ph/0304269 | Burkhard Kaempfer | B. Kampfer, J. Cleymans, P. Steinberg, S. Wheaton | Strangeness Saturation: Dependence on System-Size, Centrality and Energy | contribution for Proc. 19th Winter Workshop on Nuclear Dynamics,
Breckenridge, February 8-15, 2003 | HeavyIonPhys.21:207-213,2004 | 10.1556/APH.21.2004.2-4.17 | null | hep-ph | null | The dependence of the strangeness saturation factor on the system size,
centrality and energy is studied in relativistic heavy-ion collisions.
| [
{
"created": "Tue, 29 Apr 2003 11:38:21 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Kampfer",
"B.",
""
],
[
"Cleymans",
"J.",
""
],
[
"Steinberg",
"P.",
""
],
[
"Wheaton",
"S.",
""
]
] | The dependence of the strangeness saturation factor on the system size, centrality and energy is studied in relativistic heavy-ion collisions. |
2202.10736 | Hongrong Qi | Hao Chen and Hong-Rong Qi | The pole counting rule and XYZ states | 9 pages, 3 figures, contribution to 10th International Workshop on
Chiral Dynamics, Nov. 15-19 , 2021 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The pole counting rule is a powerful and model-independent method to
distinguish a confining state from a hadronic molecule. It has been applied to
the explorations of $X(6900)$, $X_1(2900)$ as well as $Z_c(3900)$, $X(3872)$,
$X(4660)$, etc.. For $X(6900)$, both a confining state and a molecular state
are not excluded, because lacking of enough data. For $X_1(2900)$, the analysis
shows that it should be a $\bar{D}_1 K$ molecule, with $J^P=1^-$ and an
iso-singlet interpretation is much more favorable. Finally, it is noted that
almost all XYZ particles with exotic quantum numbers can be interpreted as
hadronic molecules. The $X(3872)$ is, however, more like a charmonium.
| [
{
"created": "Tue, 22 Feb 2022 08:51:25 GMT",
"version": "v1"
}
] | 2022-02-23 | [
[
"Chen",
"Hao",
""
],
[
"Qi",
"Hong-Rong",
""
]
] | The pole counting rule is a powerful and model-independent method to distinguish a confining state from a hadronic molecule. It has been applied to the explorations of $X(6900)$, $X_1(2900)$ as well as $Z_c(3900)$, $X(3872)$, $X(4660)$, etc.. For $X(6900)$, both a confining state and a molecular state are not excluded, because lacking of enough data. For $X_1(2900)$, the analysis shows that it should be a $\bar{D}_1 K$ molecule, with $J^P=1^-$ and an iso-singlet interpretation is much more favorable. Finally, it is noted that almost all XYZ particles with exotic quantum numbers can be interpreted as hadronic molecules. The $X(3872)$ is, however, more like a charmonium. |
1807.03806 | Oscar Garcia-Montero | Sanjin Beni\'c, Kenji Fukushima, Oscar Garcia-Montero, Raju
Venugopalan | Constraining unintegrated gluon distributions from inclusive photon
production in proton-proton collisions at the LHC | 9 pages, 5 figures | null | 10.1016/j.physletb.2019.02.007 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the leading order (LO) $qg\to q \gamma$ and next-to-leading order
(NLO) $gg\to q{\bar q} \gamma$ contributions to inclusive photon production in
proton-proton (p+p) collisions at the LHC. These channels provide the dominant
contribution at LO and NLO for photon transverse momenta $k_{\gamma\perp}$
corresponding to momentum fractions of $x\leq 0.01$ in the colliding protons.
Our computations, performed in the dilute-dense framework of the Color Glass
Condensate effective field theory (CGC EFT), show that the NLO contribution
dominates at small-$x$ because it is sensitive to $k_\perp$-dependent
unintegrated gluon distributions in both of the protons. We predict a maximal
$10\%$ modification of the cross section at low $k_{\gamma\perp}$ as a direct
consequence of the violation of $k_\perp$-factorization. The coherence effects
responsible for this modification are enhanced in nuclei and can be identified
from inclusive photon measurements in proton-nucleus collisions. We provide
numerical results for the isolated inclusive photon cross section for
$k_{\gamma\perp}\leq 20$ GeV in p+p collisions that can be tested in the future
at the LHC.
| [
{
"created": "Tue, 10 Jul 2018 18:12:49 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Feb 2019 10:12:23 GMT",
"version": "v2"
}
] | 2019-02-27 | [
[
"Benić",
"Sanjin",
""
],
[
"Fukushima",
"Kenji",
""
],
[
"Garcia-Montero",
"Oscar",
""
],
[
"Venugopalan",
"Raju",
""
]
] | We compute the leading order (LO) $qg\to q \gamma$ and next-to-leading order (NLO) $gg\to q{\bar q} \gamma$ contributions to inclusive photon production in proton-proton (p+p) collisions at the LHC. These channels provide the dominant contribution at LO and NLO for photon transverse momenta $k_{\gamma\perp}$ corresponding to momentum fractions of $x\leq 0.01$ in the colliding protons. Our computations, performed in the dilute-dense framework of the Color Glass Condensate effective field theory (CGC EFT), show that the NLO contribution dominates at small-$x$ because it is sensitive to $k_\perp$-dependent unintegrated gluon distributions in both of the protons. We predict a maximal $10\%$ modification of the cross section at low $k_{\gamma\perp}$ as a direct consequence of the violation of $k_\perp$-factorization. The coherence effects responsible for this modification are enhanced in nuclei and can be identified from inclusive photon measurements in proton-nucleus collisions. We provide numerical results for the isolated inclusive photon cross section for $k_{\gamma\perp}\leq 20$ GeV in p+p collisions that can be tested in the future at the LHC. |
0811.2695 | Melahat Bayar | K. Azizi, M. Bayar, A. Ozpineci | ${\Sigma_{Q}\Lambda_{Q}\pi}$ Coupling Constant in Light Cone QCD Sum
Rules | 19 Pages, 4 Figures and one Table | Phys.Rev.D79:056002,2009 | 10.1103/PhysRevD.79.056002 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The strong coupling constants $g_{{\Sigma_{Q}\Lambda_{Q}\pi}}$ ($Q=b$ and
$c$) are studied in the framework of the light cone QCD sum rules using the
most general form of the baryonic currents. The predicted coupling constants
are used to estimate the decay widths for the
$\Sigma_{Q}\longrightarrow\Lambda_{Q}\pi$ decays which are compared with the
predictions of the other approaches and existing experimental data.
| [
{
"created": "Mon, 17 Nov 2008 13:05:27 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Jan 2009 14:12:11 GMT",
"version": "v2"
}
] | 2009-11-06 | [
[
"Azizi",
"K.",
""
],
[
"Bayar",
"M.",
""
],
[
"Ozpineci",
"A.",
""
]
] | The strong coupling constants $g_{{\Sigma_{Q}\Lambda_{Q}\pi}}$ ($Q=b$ and $c$) are studied in the framework of the light cone QCD sum rules using the most general form of the baryonic currents. The predicted coupling constants are used to estimate the decay widths for the $\Sigma_{Q}\longrightarrow\Lambda_{Q}\pi$ decays which are compared with the predictions of the other approaches and existing experimental data. |
1010.3708 | Ivan Vitev | R. B. Neufeld, I. Vitev, B. W. Zhang | A possible determination of the quark radiation length in cold nuclear
matter | 8 pages, 4 figures | Physics Letters B, Vol. 704, Iss. 5, 2011, Pp. 590-595 | 10.1016/j.physletb.2011.09.045 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the differential Drell-Yan production cross section in
proton-nucleus collisions by including both next-to-leading order perturbative
effects and effects of the nuclear medium. We demonstrate that dilepton
production in fixed target experiments is an excellent tool to study
initial-state parton energy loss in large nuclei and to accurately determine
the stopping power of cold nuclear matter. We provide theoretical predictions
for the attenuation of the Drell-Yan cross section at large values of Feynman
$x_F$ and show that for low proton beam energies experimental measurements at
Fermilab's E906 can clearly distinguish between nuclear shadowing and energy
loss effects. If confirmed by data, our results may help determine the quark
radiation length in cold nuclear matter $X_0 \sim 10^{-13}$ m.
| [
{
"created": "Mon, 18 Oct 2010 20:01:13 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Oct 2011 17:05:59 GMT",
"version": "v2"
}
] | 2015-05-20 | [
[
"Neufeld",
"R. B.",
""
],
[
"Vitev",
"I.",
""
],
[
"Zhang",
"B. W.",
""
]
] | We calculate the differential Drell-Yan production cross section in proton-nucleus collisions by including both next-to-leading order perturbative effects and effects of the nuclear medium. We demonstrate that dilepton production in fixed target experiments is an excellent tool to study initial-state parton energy loss in large nuclei and to accurately determine the stopping power of cold nuclear matter. We provide theoretical predictions for the attenuation of the Drell-Yan cross section at large values of Feynman $x_F$ and show that for low proton beam energies experimental measurements at Fermilab's E906 can clearly distinguish between nuclear shadowing and energy loss effects. If confirmed by data, our results may help determine the quark radiation length in cold nuclear matter $X_0 \sim 10^{-13}$ m. |
1901.09016 | Eric Moffat | E. Moffat, T. C. Rogers, W. Melnitchouk, N. Sato, F. Steffens | What does kinematical target mass sensitivity in DIS reveal about hadron
structure? | 25 pages, 2 figures | Phys. Rev. D 99, 096008 (2019) | 10.1103/PhysRevD.99.096008 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the role of purely external kinematical approximations in inclusive
deep-inelastic lepton--hadron scattering within QCD factorization, and consider
factorization with an exact treatment of the target hadron mass. We discuss how
an observed phenomenological improvement obtained by accounting for target mass
kinematics could be interpreted in terms of general properties of target
structure, and argue that such an improvement implies a hierarchy of
nonperturbative scales within the hadron.
| [
{
"created": "Fri, 25 Jan 2019 18:36:20 GMT",
"version": "v1"
}
] | 2019-05-15 | [
[
"Moffat",
"E.",
""
],
[
"Rogers",
"T. C.",
""
],
[
"Melnitchouk",
"W.",
""
],
[
"Sato",
"N.",
""
],
[
"Steffens",
"F.",
""
]
] | We study the role of purely external kinematical approximations in inclusive deep-inelastic lepton--hadron scattering within QCD factorization, and consider factorization with an exact treatment of the target hadron mass. We discuss how an observed phenomenological improvement obtained by accounting for target mass kinematics could be interpreted in terms of general properties of target structure, and argue that such an improvement implies a hierarchy of nonperturbative scales within the hadron. |
hep-ph/9911249 | Arnd Brandenburg | A. Brandenburg, M. Flesch, P. Uwer | Polarization and spin correlations of top quarks at a future e+ e-
linear collider | 11 pages (LaTeX), 16 Postscript figure. Contribution to the
International Workshop on "Symmetry and Spin", PRAHA-SPIN99, Prague, Czech
Republic, September 5 -12, 1999 | Czech.J.Phys. 50S1 (2000) 51-58 | 10.1007/s10582-000-0006-0 | Saclay/SPhT-T99/132 | hep-ph | null | We discuss the polarization and spin correlations of top quarks produced
above threshold at a future linear collider, including QCD radiative
corrections.
| [
{
"created": "Fri, 5 Nov 1999 10:42:00 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Brandenburg",
"A.",
""
],
[
"Flesch",
"M.",
""
],
[
"Uwer",
"P.",
""
]
] | We discuss the polarization and spin correlations of top quarks produced above threshold at a future linear collider, including QCD radiative corrections. |
hep-ph/0405198 | Silvia Pascoli | Alexander Kusenko, Silvia Pascoli and Dmitry Semikoz | Bounds on heavy sterile neutrinos revisited | 14 pages, 6 figures; a detailed and expanded version | JHEP 0511:028,2005 | 10.1088/1126-6708/2005/11/028 | UCLA/04/TEP/04 | hep-ph | null | We revise the bounds on heavy sterile neutrinos, especially in the case of
their mixing with muon neutrinos in the charged current. We summarize the
present experimental limits, and we reanalyze the existing data from the
accelerator neutrino experiments and from Super-Kamiokande to set new bounds on
a heavy sterile neutrino in the range of masses from 8 MeV to 390 MeV. We also
discuss how the future accelerator neutrino experiments can improve the present
limits.
| [
{
"created": "Thu, 20 May 2004 20:48:12 GMT",
"version": "v1"
},
{
"created": "Wed, 2 Nov 2005 23:10:46 GMT",
"version": "v2"
}
] | 2010-02-03 | [
[
"Kusenko",
"Alexander",
""
],
[
"Pascoli",
"Silvia",
""
],
[
"Semikoz",
"Dmitry",
""
]
] | We revise the bounds on heavy sterile neutrinos, especially in the case of their mixing with muon neutrinos in the charged current. We summarize the present experimental limits, and we reanalyze the existing data from the accelerator neutrino experiments and from Super-Kamiokande to set new bounds on a heavy sterile neutrino in the range of masses from 8 MeV to 390 MeV. We also discuss how the future accelerator neutrino experiments can improve the present limits. |
1802.08296 | Zahra Tabrizi | Adam Falkowski, Giovanni Grilli di Cortona, Zahra Tabrizi | Future DUNE constraints on EFT | 23 pages, 4 figures; v2, agrees the version published in JHEP | JHEP04(2018)101 | 10.1007/JHEP04(2018)101 | LPT-Orsay-18-19, | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the near future, fundamental interactions at high-energy scales may be
most efficiently studied via precision measurements at low energies. A
universal language to assemble and interpret precision measurements is the
so-called SMEFT, which is an effective field theory (EFT) where the Standard
Model (SM) Lagrangian is extended by higher-dimensional operators. In this
paper we investigate the possible impact of the DUNE neutrino experiment on
constraining the SMEFT. The unprecedented neutrino flux offers an opportunity
to greatly improve the current limits via precision measurements of the trident
production and neutrino scattering off electrons and nuclei in the DUNE near
detector. We quantify the DUNE sensitivity to dimension-6 operators in the
SMEFT Lagrangian, and find that in some cases operators suppressed by an O(30)
TeV scale can be probed. We also compare the DUNE reach to that of future
experiments involving atomic parity violation and polarization asymmetry in
electron scattering, which are sensitive to an overlapping set of SMEFT
parameters.
| [
{
"created": "Thu, 22 Feb 2018 20:44:23 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Apr 2018 14:27:44 GMT",
"version": "v2"
}
] | 2018-05-10 | [
[
"Falkowski",
"Adam",
""
],
[
"di Cortona",
"Giovanni Grilli",
""
],
[
"Tabrizi",
"Zahra",
""
]
] | In the near future, fundamental interactions at high-energy scales may be most efficiently studied via precision measurements at low energies. A universal language to assemble and interpret precision measurements is the so-called SMEFT, which is an effective field theory (EFT) where the Standard Model (SM) Lagrangian is extended by higher-dimensional operators. In this paper we investigate the possible impact of the DUNE neutrino experiment on constraining the SMEFT. The unprecedented neutrino flux offers an opportunity to greatly improve the current limits via precision measurements of the trident production and neutrino scattering off electrons and nuclei in the DUNE near detector. We quantify the DUNE sensitivity to dimension-6 operators in the SMEFT Lagrangian, and find that in some cases operators suppressed by an O(30) TeV scale can be probed. We also compare the DUNE reach to that of future experiments involving atomic parity violation and polarization asymmetry in electron scattering, which are sensitive to an overlapping set of SMEFT parameters. |
1312.4688 | Matthias Steinhauser | Matthias Steinhauser | Towards analytic $(g-2)_\mu$ at four loops | 5 pages, contribution to the proceedings of the international
workshop on e+ e- collisions from Phi to Psi 2013; v2: references added | null | 10.1142/S2010194514604177 | TTP13-042, SFB/CPP-13-102 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this contribution we present recent four-loop results for the muon
anomalous magnetic moment based on analytic methods. In particular, fermionic
corrections involving two or more closed electron loops or at least one tau
lepton loop are discussed.
| [
{
"created": "Tue, 17 Dec 2013 08:44:47 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Dec 2013 08:06:05 GMT",
"version": "v2"
}
] | 2015-06-18 | [
[
"Steinhauser",
"Matthias",
""
]
] | In this contribution we present recent four-loop results for the muon anomalous magnetic moment based on analytic methods. In particular, fermionic corrections involving two or more closed electron loops or at least one tau lepton loop are discussed. |
0903.1875 | Yukihiro Mimura | Yukihiro Mimura | Flavor Symmetry in Gauge-Higgs-Matter Unified Orbifold GUTs | 17 pages | null | null | MIFP-09-11 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct an orbifold model in which all the standard model particles are
unified in a gauge multiplet in higher dimensional supersymmetric gauge theory.
We find that a flavor symmetry has to remain in four dimensions due to the
discrete charge conservation for orbifold conditions if the colored Higgs
components in the gauge multiplet are projected out. When the flavor symmetry
originates from the E_8 bulk gauge symmetry, the successful unification model
can be constructed. In the model, all the Dirac Yukawa couplings for quarks and
leptons are generated by the higher dimensional gauge interaction.
| [
{
"created": "Tue, 10 Mar 2009 22:27:57 GMT",
"version": "v1"
}
] | 2009-03-12 | [
[
"Mimura",
"Yukihiro",
""
]
] | We construct an orbifold model in which all the standard model particles are unified in a gauge multiplet in higher dimensional supersymmetric gauge theory. We find that a flavor symmetry has to remain in four dimensions due to the discrete charge conservation for orbifold conditions if the colored Higgs components in the gauge multiplet are projected out. When the flavor symmetry originates from the E_8 bulk gauge symmetry, the successful unification model can be constructed. In the model, all the Dirac Yukawa couplings for quarks and leptons are generated by the higher dimensional gauge interaction. |
1003.1912 | Prateek Agrawal | Prateek Agrawal, Zackaria Chacko, Can Kilic, Rashmish K. Mishra | A Classification of Dark Matter Candidates with Primarily Spin-Dependent
Interactions with Matter | 46 pages, 13 figures, pdflatex. Results extended to the case of
complex vector dark matter. References added | null | null | UMD-PP-10-004, RUNHETC-2010-07 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We perform a model-independent classification of Weakly Interacting Massive
Particle (WIMP) dark matter candidates that have the property that their
scattering off nucleons is dominated by spin-dependent interactions. We study
renormalizable theories where the scattering of dark matter is elastic and
arises at tree-level. We show that if the WIMP-nucleon cross section is
dominated by spin-dependent interactions the natural dark matter candidates are
either Majorana fermions or real vector bosons, so that the dark matter
particle is its own anti-particle. In such a scenario, scalar dark matter is
disfavored. Dirac fermion and complex vector boson dark matter are also
disfavored, except for very specific choices of quantum numbers. We further
establish that any such theory must contain either new particles close to the
weak scale with Standard Model quantum numbers, or alternatively, a $Z'$ gauge
boson with mass at or below the TeV scale. In the region of parameter space
that is of interest to current direct detection experiments, these particles
naturally lie in a mass range that is kinematically accessible to the Large
Hadron Collider (LHC).
| [
{
"created": "Tue, 9 Mar 2010 16:10:33 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Jun 2010 19:49:11 GMT",
"version": "v2"
}
] | 2010-07-01 | [
[
"Agrawal",
"Prateek",
""
],
[
"Chacko",
"Zackaria",
""
],
[
"Kilic",
"Can",
""
],
[
"Mishra",
"Rashmish K.",
""
]
] | We perform a model-independent classification of Weakly Interacting Massive Particle (WIMP) dark matter candidates that have the property that their scattering off nucleons is dominated by spin-dependent interactions. We study renormalizable theories where the scattering of dark matter is elastic and arises at tree-level. We show that if the WIMP-nucleon cross section is dominated by spin-dependent interactions the natural dark matter candidates are either Majorana fermions or real vector bosons, so that the dark matter particle is its own anti-particle. In such a scenario, scalar dark matter is disfavored. Dirac fermion and complex vector boson dark matter are also disfavored, except for very specific choices of quantum numbers. We further establish that any such theory must contain either new particles close to the weak scale with Standard Model quantum numbers, or alternatively, a $Z'$ gauge boson with mass at or below the TeV scale. In the region of parameter space that is of interest to current direct detection experiments, these particles naturally lie in a mass range that is kinematically accessible to the Large Hadron Collider (LHC). |
hep-ph/0609056 | Teiji Kunihiro | K. Tsumura, T. Kunihiro and K. Ohnishi | Derivation of Covariant Dissipative Fluid Dynamics in the
Renormalization-group Method | Serious typos and a minor one are corrected in p.6 and 7, and in p.1,
respectively | Erratum-ibid.B656:274,2007 | 10.1016/j.physletb.2007.10.003 | YITP-06-46 | hep-ph cond-mat.stat-mech hep-th nucl-th physics.flu-dyn | null | We derive generic relativistic hydrodynamical equations with dissipative
effects from the underlying Boltzmann equation in a mechanical and systematic
way on the basis of so called the renormalization-group (RG) method. A
macroscopic frame vector is introduced to specify the frame on which the
macroscopic dynamics is described. Our method is so mechanical with only few
ansatz that our method give a microscopic foundation of the available
hydrodynamical equations, and also can be applied to make a reduction of the
kinetic equations other than the simple Boltzmann equation.
| [
{
"created": "Wed, 6 Sep 2006 05:10:43 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Dec 2006 04:41:15 GMT",
"version": "v2"
},
{
"created": "Fri, 29 Dec 2006 01:38:01 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Tsumura",
"K.",
""
],
[
"Kunihiro",
"T.",
""
],
[
"Ohnishi",
"K.",
""
]
] | We derive generic relativistic hydrodynamical equations with dissipative effects from the underlying Boltzmann equation in a mechanical and systematic way on the basis of so called the renormalization-group (RG) method. A macroscopic frame vector is introduced to specify the frame on which the macroscopic dynamics is described. Our method is so mechanical with only few ansatz that our method give a microscopic foundation of the available hydrodynamical equations, and also can be applied to make a reduction of the kinetic equations other than the simple Boltzmann equation. |
hep-ph/9805240 | Christopher Kolda | Christopher Kolda and Nir Polonsky | Supergravity Resolution of the Unification to Planck Scale Hierarchy | 6 pages, LaTeX | Phys.Lett. B433 (1998) 323-327 | 10.1016/S0370-2693(98)00711-4 | IASSNS-HEP-98-40, RU-98-15 | hep-ph | null | It is demonstrated how the hierarchy between the gauge coupling unification
scale of minimal supersymmetry and the Planck (or string) scale, which
resembles in order of magnitude a loop factor, can actually be explained as
such in supergravity-coupled supersymmetry. A gauge and global singlet field
acquires a linear potential term due to its one-loop supergravity interactions
and slides to the desired scale. The singlet field can then provide the seed
for the breaking of the unified theory at the appropriate scale via its
couplings to fields in the adjoint representation.
| [
{
"created": "Wed, 6 May 1998 20:45:41 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Kolda",
"Christopher",
""
],
[
"Polonsky",
"Nir",
""
]
] | It is demonstrated how the hierarchy between the gauge coupling unification scale of minimal supersymmetry and the Planck (or string) scale, which resembles in order of magnitude a loop factor, can actually be explained as such in supergravity-coupled supersymmetry. A gauge and global singlet field acquires a linear potential term due to its one-loop supergravity interactions and slides to the desired scale. The singlet field can then provide the seed for the breaking of the unified theory at the appropriate scale via its couplings to fields in the adjoint representation. |
1807.07578 | Patrick Meade | Patrick Meade and Harikrishnan Ramani | Unrestored Electroweak Symmetry | 7 pages, 4 figures | Phys. Rev. Lett. 122, 041802 (2019) | 10.1103/PhysRevLett.122.041802 | YITP-SB-18-19 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The commonly assumed cosmological history of our universe is that at
early-times and high-temperatures the universe went through an ElectroWeak
Phase Transition (EWPT). Assuming an EWPT, and depending on its strength, there
are many implications for baryogenesis, gravitational waves, and the evolution
of the universe in general. However, it is not true that all spontaneously
broken symmetries at zero-temperature are restored at high-temperature. In
particular the idea of "inverse symmetry breaking" has long been established in
scalar theories with evidence from both perturbative and lattice calculations.
In this letter we demonstrate that with a simple extension of the SM it is
possible that the ElectroWeak (EW) symmetry was always broken or only
temporarily passed through a symmetry restored phase. These novel phase
histories have many cosmological and collider implications that we discuss. The
model presented here serves as a useful benchmark comparison for future
attempts to discern the phase of our universe at $T\gtrsim$ a few GeV.
| [
{
"created": "Thu, 19 Jul 2018 18:00:03 GMT",
"version": "v1"
}
] | 2019-02-06 | [
[
"Meade",
"Patrick",
""
],
[
"Ramani",
"Harikrishnan",
""
]
] | The commonly assumed cosmological history of our universe is that at early-times and high-temperatures the universe went through an ElectroWeak Phase Transition (EWPT). Assuming an EWPT, and depending on its strength, there are many implications for baryogenesis, gravitational waves, and the evolution of the universe in general. However, it is not true that all spontaneously broken symmetries at zero-temperature are restored at high-temperature. In particular the idea of "inverse symmetry breaking" has long been established in scalar theories with evidence from both perturbative and lattice calculations. In this letter we demonstrate that with a simple extension of the SM it is possible that the ElectroWeak (EW) symmetry was always broken or only temporarily passed through a symmetry restored phase. These novel phase histories have many cosmological and collider implications that we discuss. The model presented here serves as a useful benchmark comparison for future attempts to discern the phase of our universe at $T\gtrsim$ a few GeV. |
2309.15992 | Di An | Di An | $N^* (1520)$ transition form factors from dispersion theory | Conference Proceedings for meson 23. The conference proceedings will
be published as a special issue of EPJ Web of Conferences | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The electromagnetic transition form factors (TFFs) of the nucleon provide
important information on the internal structure of hadrons. A model-independent
dispersive calculation of the electromagnetic TFFs $N^{*}(1520)\to N$ at low
energies is presented. Taking pion rescattering into consideration, we derived
dispersive relations for the $N^{*}(1520)\to N$ TFFs that relate space-like and
time-like regions from the first principles. Based on the space-like data from
JLab and hadronic data measured by HADES, we make predictions for TFFs in the
time-like region. Our predictions can be tested in future experiments (e.g.
HADES).
| [
{
"created": "Wed, 27 Sep 2023 20:14:48 GMT",
"version": "v1"
}
] | 2023-09-29 | [
[
"An",
"Di",
""
]
] | The electromagnetic transition form factors (TFFs) of the nucleon provide important information on the internal structure of hadrons. A model-independent dispersive calculation of the electromagnetic TFFs $N^{*}(1520)\to N$ at low energies is presented. Taking pion rescattering into consideration, we derived dispersive relations for the $N^{*}(1520)\to N$ TFFs that relate space-like and time-like regions from the first principles. Based on the space-like data from JLab and hadronic data measured by HADES, we make predictions for TFFs in the time-like region. Our predictions can be tested in future experiments (e.g. HADES). |
0811.1598 | Arjun Menon | Thomas Flacke, A. Menon, and Daniel J. Phalen | Non-minimal universal extra dimensions | 38 pages, 8 figures, added references, accepted by PRD | null | 10.1103/PhysRevD.79.056009 | MCTP-08-64 | hep-ph astro-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we investigate the phenomenological implications of boundary
localized terms (BLTs) in the model of Universal Extra Dimensions (UED). In
particular, we study the electroweak Kaluza-Klein mass spectrum resulting from
BLTs and their effect on electroweak symmetry breaking via the five dimensional
Higgs mechanism. We find that the addition of BLTs to massive five dimensional
fields induces a non-trivial extra dimensional profile for the zero and
non-zero Kaluza-Klein (KK) modes. Hence BLTs generically lead to a modification
of Standard Model parameters and are therefore experimentally constrained, even
at tree level. We study Standard Model constraints on three representative
non-minimal UED models in detail and find that the constraints on BLTs are
weak. On the contrary, non-zero BLTs have a major impact on the spectrum and
couplings of non-zero KK modes. For example, there are regions of parameter
space where the Lightest Kaluza-Klein particle (LKP) is either the Kaluza-Klein
Higgs boson or the first KK mode of the W^3.
| [
{
"created": "Mon, 10 Nov 2008 22:29:15 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Mar 2009 20:19:11 GMT",
"version": "v2"
}
] | 2009-11-13 | [
[
"Flacke",
"Thomas",
""
],
[
"Menon",
"A.",
""
],
[
"Phalen",
"Daniel J.",
""
]
] | In this paper we investigate the phenomenological implications of boundary localized terms (BLTs) in the model of Universal Extra Dimensions (UED). In particular, we study the electroweak Kaluza-Klein mass spectrum resulting from BLTs and their effect on electroweak symmetry breaking via the five dimensional Higgs mechanism. We find that the addition of BLTs to massive five dimensional fields induces a non-trivial extra dimensional profile for the zero and non-zero Kaluza-Klein (KK) modes. Hence BLTs generically lead to a modification of Standard Model parameters and are therefore experimentally constrained, even at tree level. We study Standard Model constraints on three representative non-minimal UED models in detail and find that the constraints on BLTs are weak. On the contrary, non-zero BLTs have a major impact on the spectrum and couplings of non-zero KK modes. For example, there are regions of parameter space where the Lightest Kaluza-Klein particle (LKP) is either the Kaluza-Klein Higgs boson or the first KK mode of the W^3. |
1211.1959 | Roberto Vega-Morales | Yi Chen, Nhan Tran, Roberto Vega-Morales | Scrutinizing the Higgs Signal and Background in the $2e2\mu$ Golden
Channel | References added | null | 10.1007/JHEP01(2013)182 | FERMILAB-PUB-12-588-E-PPD-T, NUHEP-th/12-13, CALT-68-2894 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Kinematic distributions in the decays of the newly discovered resonance to
four leptons are a powerful test of the tensor structure of its couplings to
electroweak gauge bosons. We present an analytic calculation for both signal
and background of the fully differential cross section for the `Golden Channel'
$e^+e^-\mu^+\mu^-$ final state. We include all interference effects between
intermediate gauge bosons and allow them to be on- or off-shell. For the signal
we compute the fully differential cross section for general scalar couplings to
$ZZ$, $\gamma\gamma$, and $Z\gamma$. For the background we compute the leading
order fully differential cross section for the dominant contribution coming
from $q\bar{q}$ annihilation into $Z$ and $\gamma$ gauge bosons, including the
contribution from the resonant $Z\rightarrow 2e2\mu$ process. We also present
singly and doubly differential projections and study the interference effects
on the differential spectra. These expressions can be used in a variety of ways
to uncover the nature of the newly discovered resonance or any new scalars
decaying to neutral gauge bosons which might be discovered in the future.
| [
{
"created": "Thu, 8 Nov 2012 20:03:18 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Nov 2012 20:08:57 GMT",
"version": "v2"
},
{
"created": "Mon, 24 Dec 2012 00:38:16 GMT",
"version": "v3"
},
{
"created": "Fri, 1 Mar 2013 17:15:28 GMT",
"version": "v4"
},
{
"cre... | 2013-11-26 | [
[
"Chen",
"Yi",
""
],
[
"Tran",
"Nhan",
""
],
[
"Vega-Morales",
"Roberto",
""
]
] | Kinematic distributions in the decays of the newly discovered resonance to four leptons are a powerful test of the tensor structure of its couplings to electroweak gauge bosons. We present an analytic calculation for both signal and background of the fully differential cross section for the `Golden Channel' $e^+e^-\mu^+\mu^-$ final state. We include all interference effects between intermediate gauge bosons and allow them to be on- or off-shell. For the signal we compute the fully differential cross section for general scalar couplings to $ZZ$, $\gamma\gamma$, and $Z\gamma$. For the background we compute the leading order fully differential cross section for the dominant contribution coming from $q\bar{q}$ annihilation into $Z$ and $\gamma$ gauge bosons, including the contribution from the resonant $Z\rightarrow 2e2\mu$ process. We also present singly and doubly differential projections and study the interference effects on the differential spectra. These expressions can be used in a variety of ways to uncover the nature of the newly discovered resonance or any new scalars decaying to neutral gauge bosons which might be discovered in the future. |
2011.12386 | Marco Frasca | Marco Frasca | Confinement studies in QCD with Dyson-Schwinger equations | 5 pages, 2 figures. Talk given at 23th International Conference in
Quantum Chromodynamics (QCD 20, 35th anniversary), 27-30 October 2020,
Montpellier - FR | Nuclear and Particle Physics Proceedings 312-317, 161-165 (2021) | 10.1016/j.nuclphysbps.2021.05.044 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We provide a study of quantum chromodynamics with the technique of
Dyson-Schwinger equations in differential form. In this way, we are able to
approach the non-perturbative limit and recover, with some approximations, the
't Hooft limit of the theory. Quark mass in the propagator term goes off-shell
at low-energies signaling confinement. A condition for such occurrence in the
theory is provided.
| [
{
"created": "Tue, 24 Nov 2020 21:05:10 GMT",
"version": "v1"
}
] | 2022-11-22 | [
[
"Frasca",
"Marco",
""
]
] | We provide a study of quantum chromodynamics with the technique of Dyson-Schwinger equations in differential form. In this way, we are able to approach the non-perturbative limit and recover, with some approximations, the 't Hooft limit of the theory. Quark mass in the propagator term goes off-shell at low-energies signaling confinement. A condition for such occurrence in the theory is provided. |
1606.06907 | Prashant Shukla | Prashant Shukla and Sundaresh Sankrith | Energy and angular distributions of atmospheric muons at the Earth | 13 pages, 9 figures | null | null | null | hep-ph astro-ph.HE hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A fair knowledge of the atmospheric muon distributions at Earth is a
prerequisite for the simulations of cosmic ray setups and rare event search
detectors. A modified power law is proposed for atmospheric muon energy
distribution which gives a good description of the cosmic muon data in low as
well as high energy regime. Using this distribution, analytical forms for
zenith angle ($\theta$) distribution are obtained. Assuming a flat Earth, it
leads to the $\cos^{n-1}\theta$ form where it is shown that the parameter $n$
is nothing but the power of the energy distribution. Exact analytical function
is obtained for inclined trajectory of muon. A new closed form for zenith angle
distribution is obtained without assuming a flat Earth and which gives an
improved description of the data at all angles even above $70^o$. These
distributions are tested with the available atmospheric muon data of energy and
angular distributions. The parameters of these distributions can be used to
characterize the cosmic muon data as a function of energy, angle and altitude.
| [
{
"created": "Wed, 22 Jun 2016 11:42:56 GMT",
"version": "v1"
},
{
"created": "Thu, 23 Jun 2016 04:57:48 GMT",
"version": "v2"
},
{
"created": "Thu, 27 Sep 2018 19:02:30 GMT",
"version": "v3"
}
] | 2018-10-01 | [
[
"Shukla",
"Prashant",
""
],
[
"Sankrith",
"Sundaresh",
""
]
] | A fair knowledge of the atmospheric muon distributions at Earth is a prerequisite for the simulations of cosmic ray setups and rare event search detectors. A modified power law is proposed for atmospheric muon energy distribution which gives a good description of the cosmic muon data in low as well as high energy regime. Using this distribution, analytical forms for zenith angle ($\theta$) distribution are obtained. Assuming a flat Earth, it leads to the $\cos^{n-1}\theta$ form where it is shown that the parameter $n$ is nothing but the power of the energy distribution. Exact analytical function is obtained for inclined trajectory of muon. A new closed form for zenith angle distribution is obtained without assuming a flat Earth and which gives an improved description of the data at all angles even above $70^o$. These distributions are tested with the available atmospheric muon data of energy and angular distributions. The parameters of these distributions can be used to characterize the cosmic muon data as a function of energy, angle and altitude. |
1708.01655 | Yu-Sheng Liu | Yu-Sheng Liu | Possible Beyond the Standard Model Physics Motivated by Muonic Puzzles | 90 pages, 32 figures, PhD thesis, Univ Wash (2017) | null | null | null | hep-ph hep-ex nucl-th physics.atom-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent measurements of the proton radius using the Lamb shift in muonic
hydrogen are troublingly discrepant with values extracted from hydrogen
spectroscopy and electron-proton scattering experiments. This discrepancy,
which differs by more than five standard deviations, may be a signal of new
physics caused by a violation of lepton universality. Another candidate for a
new physics signal is the muon anomalous magnetic moment. The measurement at
BNL differs from the standard model prediction by at least three standard
deviations. Motivated by these two puzzles, first we use polarized
lepton-nucleon elastic scattering to search for a new scalar boson, and
furthermore we suggest new measurements of the nucleon form factors. Next, we
display a method to analyze the beam dump experiments without using
approximation on phase space, and we use it to constrain all possible new
spin-0 and spin-1 particles, and a variety of other measurements to study the
possibility of the new physics. Finally, assuming a new scalar boson can solve
the two puzzles simultaneously, we present a general model-independent analysis
and constrain the existence of the new physics.
| [
{
"created": "Fri, 4 Aug 2017 20:23:40 GMT",
"version": "v1"
}
] | 2017-08-08 | [
[
"Liu",
"Yu-Sheng",
""
]
] | Recent measurements of the proton radius using the Lamb shift in muonic hydrogen are troublingly discrepant with values extracted from hydrogen spectroscopy and electron-proton scattering experiments. This discrepancy, which differs by more than five standard deviations, may be a signal of new physics caused by a violation of lepton universality. Another candidate for a new physics signal is the muon anomalous magnetic moment. The measurement at BNL differs from the standard model prediction by at least three standard deviations. Motivated by these two puzzles, first we use polarized lepton-nucleon elastic scattering to search for a new scalar boson, and furthermore we suggest new measurements of the nucleon form factors. Next, we display a method to analyze the beam dump experiments without using approximation on phase space, and we use it to constrain all possible new spin-0 and spin-1 particles, and a variety of other measurements to study the possibility of the new physics. Finally, assuming a new scalar boson can solve the two puzzles simultaneously, we present a general model-independent analysis and constrain the existence of the new physics. |
1412.7045 | Jean Cleymans | J. Cleymans | Status of the Thermal Model and Chemical Freeze-Out | 5 pages, 6 figures presented at 3rd International Conference on New
Frontiers in Physics, Crete, Greece | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A brief review is presented of the status of the thermal model and chemical
freeze-out in relativistic heavy-ion collisions. Some interewsting aspects at
lower energies are emphasized.
| [
{
"created": "Mon, 22 Dec 2014 16:37:21 GMT",
"version": "v1"
}
] | 2014-12-23 | [
[
"Cleymans",
"J.",
""
]
] | A brief review is presented of the status of the thermal model and chemical freeze-out in relativistic heavy-ion collisions. Some interewsting aspects at lower energies are emphasized. |
hep-ph/0001193 | Dmitri Antonov | Dmitri Antonov (INFN, Pisa) | Testing Nonperturbative Ansaetze for the QCD Field Strength Correlator | 10 pages, LaTeX2e, 1 table, no figures | Phys.Lett. B479 (2000) 387-394 | 10.1016/S0370-2693(00)00337-3 | null | hep-ph | null | A test for the Gaussian and exponential Ansaetze for the nonperturbative
parts of the coefficient functions, D^{nonpert.} and D_1^{nonpert.}, which
parametrize the gauge-invariant bilocal correlator of the field strength
tensors in the stochastic vacuum model of QCD, is proposed. It is based on the
evaluation of the heavy-quark condensate within this model by making use of the
world-line formalism and equating the obtained result to the one following
directly from the QCD Lagrangian. This yields a certain relation between
D^{nonpert.}(0) and D_1^{nonpert.}(0), which is further compared with an
analogous relation between these quantities known from the existing lattice
data. Such a comparison leads to the conclusion that at the distances smaller
than the correlation length of the vacuum, Gaussian Ansatz is more suitable
than the exponential one.
| [
{
"created": "Wed, 19 Jan 2000 12:14:12 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Antonov",
"Dmitri",
"",
"INFN, Pisa"
]
] | A test for the Gaussian and exponential Ansaetze for the nonperturbative parts of the coefficient functions, D^{nonpert.} and D_1^{nonpert.}, which parametrize the gauge-invariant bilocal correlator of the field strength tensors in the stochastic vacuum model of QCD, is proposed. It is based on the evaluation of the heavy-quark condensate within this model by making use of the world-line formalism and equating the obtained result to the one following directly from the QCD Lagrangian. This yields a certain relation between D^{nonpert.}(0) and D_1^{nonpert.}(0), which is further compared with an analogous relation between these quantities known from the existing lattice data. Such a comparison leads to the conclusion that at the distances smaller than the correlation length of the vacuum, Gaussian Ansatz is more suitable than the exponential one. |
1707.09303 | Alfred Stadler | Sofia Leit\~ao, Alfred Stadler, M. T. Pe\~na, Elmar P. Biernat | Covariant spectator theory of quark-antiquark bound states: Mass spectra
and vertex functions of heavy and heavy-light mesons | 23 pages, 10 figures. Minor corrections of previous version. To be
published in Phys. Rev. D | null | 10.1103/PhysRevD.96.074007 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the covariant spectator theory with an effective quark-antiquark
interaction, containing Lorentz scalar, pseudoscalar, and vector contributions,
to calculate the masses and vertex functions of, simultaneously, heavy and
heavy-light mesons. We perform least-square fits of the model parameters,
including the quark masses, to the meson spectrum and systematically study the
sensitivity of the parameters with respect to different sets of fitted data. We
investigate the influence of the vector confining interaction by using a
continuous parameter controlling its weight. We find that vector contributions
to the confining interaction between 0% and about 30% lead to essentially the
same agreement with the data. Similarly, the light quark masses are not very
tightly constrained. In all cases, the meson mass spectra calculated with our
fitted models agree very well with the experimental data. We also calculate the
mesons wave functions in a partial wave representation and show how they are
related to the meson vertex functions in covariant form.
| [
{
"created": "Fri, 28 Jul 2017 16:13:19 GMT",
"version": "v1"
},
{
"created": "Tue, 26 Sep 2017 17:26:04 GMT",
"version": "v2"
}
] | 2017-10-25 | [
[
"Leitão",
"Sofia",
""
],
[
"Stadler",
"Alfred",
""
],
[
"Peña",
"M. T.",
""
],
[
"Biernat",
"Elmar P.",
""
]
] | We use the covariant spectator theory with an effective quark-antiquark interaction, containing Lorentz scalar, pseudoscalar, and vector contributions, to calculate the masses and vertex functions of, simultaneously, heavy and heavy-light mesons. We perform least-square fits of the model parameters, including the quark masses, to the meson spectrum and systematically study the sensitivity of the parameters with respect to different sets of fitted data. We investigate the influence of the vector confining interaction by using a continuous parameter controlling its weight. We find that vector contributions to the confining interaction between 0% and about 30% lead to essentially the same agreement with the data. Similarly, the light quark masses are not very tightly constrained. In all cases, the meson mass spectra calculated with our fitted models agree very well with the experimental data. We also calculate the mesons wave functions in a partial wave representation and show how they are related to the meson vertex functions in covariant form. |
hep-ph/0212283 | Aleksi Vuorinen | A. Vuorinen | Quark number susceptibilities of hot QCD up to g^6ln(g) | 11 pages, 3 figures Typos corrected, references added, figures
modified | Phys.Rev. D67 (2003) 074032 | 10.1103/PhysRevD.67.074032 | HIP-2002-66/TH | hep-ph | null | The pressure of hot QCD has recently been determined to the last
perturbatively computable order g^6 ln(g) by Kajantie et al. using
three-dimensional effective theories. A similar method is applied here to the
pressure in the presence of small but non-vanishing quark chemical potentials,
and the result is used to derive the quark number susceptibilities in the limit
mu = 0. The diagonal quark number susceptibility of QCD with n_f flavours of
massless quarks is evaluated to order g^6ln(g) and compared with recent lattice
simulations. It is observed that the results qualitatively resemble the lattice
ones, and that when combined with the fully perturbative but yet undetermined
g^6 term they may well explain the behaviour of the lattice data for a wide
range of temperatures.
| [
{
"created": "Thu, 19 Dec 2002 11:19:01 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Mar 2003 14:15:11 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Vuorinen",
"A.",
""
]
] | The pressure of hot QCD has recently been determined to the last perturbatively computable order g^6 ln(g) by Kajantie et al. using three-dimensional effective theories. A similar method is applied here to the pressure in the presence of small but non-vanishing quark chemical potentials, and the result is used to derive the quark number susceptibilities in the limit mu = 0. The diagonal quark number susceptibility of QCD with n_f flavours of massless quarks is evaluated to order g^6ln(g) and compared with recent lattice simulations. It is observed that the results qualitatively resemble the lattice ones, and that when combined with the fully perturbative but yet undetermined g^6 term they may well explain the behaviour of the lattice data for a wide range of temperatures. |
hep-ph/0209202 | Arnd Brandenburg | W. Bernreuther, A. Brandenburg, Z.G. Si, P. Uwer | Top quark pair production and decay at hadron colliders: Predictions at
NLO QCD including spin correlations | 4 pages, 1 figure. Contribution to the Proceedings of the 31st
International Conference on High Energy Physics (ICHEP 2002) | null | 10.1016/S0920-5632(03)90550-0 | DESY 02-144, PITHA 02/15, TTP02-24 | hep-ph | null | We present results at NLO QCD for hadronic production and decay of top quark
pairs, taking into account t tbar spin correlations.
| [
{
"created": "Wed, 18 Sep 2002 13:16:54 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Bernreuther",
"W.",
""
],
[
"Brandenburg",
"A.",
""
],
[
"Si",
"Z. G.",
""
],
[
"Uwer",
"P.",
""
]
] | We present results at NLO QCD for hadronic production and decay of top quark pairs, taking into account t tbar spin correlations. |
1603.05304 | Christoph Englert | Christoph Englert, Rogerio Rosenfeld, Michael Spannowsky, Alberto
Tonero | New physics and signal-background interference in associated $pp\to HZ$
production | 6 pages, 5 figures, references added, published version | null | 10.1209/0295-5075/114/31001 | IPPP/16/21, DCPT/16/42 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We re-investigate electroweak signal-background interference in associated
Higgs production via gluon fusion in the presence of new physics in the
top-Higgs sector. Considering the full final state $pp \to b \bar b
\ell^+\ell^-$ ($\ell=e,\mu$), we discuss how new physics in the top-Higgs
sector that enhances the $ZZ$ component can leave footprints in the $HZ$ limit
setting. In passing we investigate the phenomenology of a class of new physics
interactions that can be genuinely studied in this process.
| [
{
"created": "Wed, 16 Mar 2016 22:34:55 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Jun 2016 14:31:29 GMT",
"version": "v2"
}
] | 2016-06-22 | [
[
"Englert",
"Christoph",
""
],
[
"Rosenfeld",
"Rogerio",
""
],
[
"Spannowsky",
"Michael",
""
],
[
"Tonero",
"Alberto",
""
]
] | We re-investigate electroweak signal-background interference in associated Higgs production via gluon fusion in the presence of new physics in the top-Higgs sector. Considering the full final state $pp \to b \bar b \ell^+\ell^-$ ($\ell=e,\mu$), we discuss how new physics in the top-Higgs sector that enhances the $ZZ$ component can leave footprints in the $HZ$ limit setting. In passing we investigate the phenomenology of a class of new physics interactions that can be genuinely studied in this process. |
1605.04308 | Bryan Ostdiek | Timothy Cohen, Graham D. Kribs, Ann E. Nelson, and Bryan Ostdiek | 750 GeV Diphotons from Supersymmetry with Dirac Gauginos | v2: Published version. Minor updates and added references. v1: 34
pages, 5 figures | Phys. Rev. D 94, 015031 (2016) | 10.1103/PhysRevD.94.015031 | NSF-KITP-16-058 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the recent excess in the diphoton invariant mass near 750 GeV,
we explore a supersymmetric extension of the Standard Model that includes the
minimal set of superpartners as well as additional Dirac partner chiral
superfields in the adjoint representation for each gauge group. The bino
partner pseudoscalar is identified as the 750 GeV resonance, while
superpotential interactions between it and the gluino (wino) partners yield
production via gluon fusion (decay to photon pairs) at one-loop. The gauginos
and these additional adjoint superpartners are married by a Dirac mass and must
also have Majorana masses. While a large wino partner Majorana mass is
necessary to explain the excess, the gluino can be approximately Dirac-like,
providing benefits consistent with being both "supersoft" (loop corrections to
the scalar masses from Dirac gauginos are free of logarithmic enhancements) and
"supersafe" (the experimental limits on the squark/gluino masses can be relaxed
due to the reduced production rate). Consistency with the measured Standard
Model-like Higgs boson mass is imposed, and a numerical exploration of the
parameter space is provided. Models that can account for the diphoton excess
are additionally characterized by having couplings that can remain perturbative
up to very high scales, while remaining consistent with experimental
constraints, the Higgs boson mass, and an electroweak scale which is not
excessively fine tuned.
| [
{
"created": "Fri, 13 May 2016 20:00:00 GMT",
"version": "v1"
},
{
"created": "Fri, 29 Jul 2016 17:39:01 GMT",
"version": "v2"
}
] | 2016-08-03 | [
[
"Cohen",
"Timothy",
""
],
[
"Kribs",
"Graham D.",
""
],
[
"Nelson",
"Ann E.",
""
],
[
"Ostdiek",
"Bryan",
""
]
] | Motivated by the recent excess in the diphoton invariant mass near 750 GeV, we explore a supersymmetric extension of the Standard Model that includes the minimal set of superpartners as well as additional Dirac partner chiral superfields in the adjoint representation for each gauge group. The bino partner pseudoscalar is identified as the 750 GeV resonance, while superpotential interactions between it and the gluino (wino) partners yield production via gluon fusion (decay to photon pairs) at one-loop. The gauginos and these additional adjoint superpartners are married by a Dirac mass and must also have Majorana masses. While a large wino partner Majorana mass is necessary to explain the excess, the gluino can be approximately Dirac-like, providing benefits consistent with being both "supersoft" (loop corrections to the scalar masses from Dirac gauginos are free of logarithmic enhancements) and "supersafe" (the experimental limits on the squark/gluino masses can be relaxed due to the reduced production rate). Consistency with the measured Standard Model-like Higgs boson mass is imposed, and a numerical exploration of the parameter space is provided. Models that can account for the diphoton excess are additionally characterized by having couplings that can remain perturbative up to very high scales, while remaining consistent with experimental constraints, the Higgs boson mass, and an electroweak scale which is not excessively fine tuned. |
hep-ph/9908307 | Mike Seymour | J.R. Forshaw (CERN/Manchester) and M.H. Seymour (RAL) | Subjet Rates in Hadron Collider Jets | 23 pages, 22 figures | JHEP 9909:009,1999 | 10.1088/1126-6708/1999/09/009 | CERN-TH/99-239, RAL-TR-1999-049, MC-TH-99/10 | hep-ph | null | We calculate the subjet rates for jets produced in hadron collisions. The kt
algorithm is used to define the jets and allows the theoretical calculation to
sum both the leading and next-to-leading logarithms in the resolution variable,
ycut. We also ensure that our calculation matches exactly the leading order in
alpha_s result and has sensible behaviour near thresholds.
| [
{
"created": "Mon, 9 Aug 1999 18:01:29 GMT",
"version": "v1"
}
] | 2010-02-03 | [
[
"Forshaw",
"J. R.",
"",
"CERN/Manchester"
],
[
"Seymour",
"M. H.",
"",
"RAL"
]
] | We calculate the subjet rates for jets produced in hadron collisions. The kt algorithm is used to define the jets and allows the theoretical calculation to sum both the leading and next-to-leading logarithms in the resolution variable, ycut. We also ensure that our calculation matches exactly the leading order in alpha_s result and has sensible behaviour near thresholds. |
hep-ph/0303018 | Rohini M. Godbole | R.M. Godbole, A. Grau, G. Pancheri and A. De Roeck | Predictions for the $\gamma \gamma$ total cross-section in the TeV
region: an update | Talk presented by A. De Roeck at the International Linear Collider
Workshop, Jeju Island, Aug. 26-30,2002. To appear in the proceedings. 10
pages, LaTeX file, requires A4.sty, four figures | null | null | CERN-TH/2002-338 | hep-ph | null | In this talk we present an update of model predictions for the $\gamma
\gamma$ total cross-section in the TeV region. The update includes preliminary
results for $\gamma \gamma $ cross-sections using the Bloch-Nordsieck model for
the overlap function of the partons in the transverse space, use of the CJLK
parametrisation of the photonic parton densities that has recently become
available and extension to the higher $\gamma \gamma$ energies relevant to the
planned CLIC collider.
| [
{
"created": "Tue, 4 Mar 2003 13:55:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Godbole",
"R. M.",
""
],
[
"Grau",
"A.",
""
],
[
"Pancheri",
"G.",
""
],
[
"De Roeck",
"A.",
""
]
] | In this talk we present an update of model predictions for the $\gamma \gamma$ total cross-section in the TeV region. The update includes preliminary results for $\gamma \gamma $ cross-sections using the Bloch-Nordsieck model for the overlap function of the partons in the transverse space, use of the CJLK parametrisation of the photonic parton densities that has recently become available and extension to the higher $\gamma \gamma$ energies relevant to the planned CLIC collider. |
0804.4543 | Mikko Laine | M. Laine, M. Shaposhnikov | Sterile neutrino dark matter as a consequence of nuMSM-induced lepton
asymmetry | 25 pages. v2: many clarifications and references added; published
version | JCAP 0806:031,2008 | 10.1088/1475-7516/2008/06/031 | null | hep-ph astro-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has been pointed out in ref.[1] that in the nuMSM (Standard Model extended
by three right-handed neutrinos with masses smaller than the electroweak
scale), there is a corner in the parameter space where CP-violating resonant
oscillations among the two heaviest right-handed neutrinos continue to operate
below the freeze-out temperature of sphaleron transitions, leading to a lepton
asymmetry which is considerably larger than the baryon asymmetry. Consequently,
the lightest right-handed (``sterile'') neutrinos, which may serve as dark
matter, are generated through an efficient resonant mechanism proposed by Shi
and Fuller [2]. We re-compute the dark matter relic density and non-equilibrium
momentum distribution function in this situation with quantum field theoretic
methods and, confronting the results with existing astrophysical data, derive
bounds on the properties of the lightest right-handed neutrinos. Our spectra
can be used as an input for structure formation simulations in warm dark matter
cosmologies, for a Lyman-alpha analysis of the dark matter distribution on
small scales, and for studying the properties of haloes of dwarf spheroidal
galaxies.
| [
{
"created": "Tue, 29 Apr 2008 07:47:45 GMT",
"version": "v1"
},
{
"created": "Sun, 29 Jun 2008 11:01:40 GMT",
"version": "v2"
}
] | 2009-01-06 | [
[
"Laine",
"M.",
""
],
[
"Shaposhnikov",
"M.",
""
]
] | It has been pointed out in ref.[1] that in the nuMSM (Standard Model extended by three right-handed neutrinos with masses smaller than the electroweak scale), there is a corner in the parameter space where CP-violating resonant oscillations among the two heaviest right-handed neutrinos continue to operate below the freeze-out temperature of sphaleron transitions, leading to a lepton asymmetry which is considerably larger than the baryon asymmetry. Consequently, the lightest right-handed (``sterile'') neutrinos, which may serve as dark matter, are generated through an efficient resonant mechanism proposed by Shi and Fuller [2]. We re-compute the dark matter relic density and non-equilibrium momentum distribution function in this situation with quantum field theoretic methods and, confronting the results with existing astrophysical data, derive bounds on the properties of the lightest right-handed neutrinos. Our spectra can be used as an input for structure formation simulations in warm dark matter cosmologies, for a Lyman-alpha analysis of the dark matter distribution on small scales, and for studying the properties of haloes of dwarf spheroidal galaxies. |
1811.12350 | Tom\'a\v{s} Husek | Tom\'a\v{s} Husek | Radiative corrections in Dalitz decays of $\pi^0$, $\eta$ and
$\eta^\prime$ mesons | 9 pages, 3 figures; contribution to the proceedings of the following
conferences: XIIIth Quark Confinement and the Hadron Spectrum, 15th
International Workshop on Meson Physics and 9th International Workshop on
Chiral Dynamics | null | 10.1051/epjconf/201919902015 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We briefly summarize current experimental and theoretical results on the two
important processes of the low-energy hadron physics involving neutral pions,
the rare decay $\pi^0\to e^+e^-$ and the Dalitz decay of $\pi^0$, and provide a
new value for the ratio $R={\Gamma(\pi^0\to
e^+e^-\gamma(\gamma))}/{\Gamma(\pi^0\to\gamma\gamma)}=11.978(6)\times10^{-3}$,
which is by two orders of magnitude more precise than the current PDG average.
This value is obtained using the complete set of the next-to-leading-order
radiative corrections in the QED sector, and incorporates up-to-date values of
the $\pi^0$-transition-form-factor slope. The ratio $R$ translates into the
branching ratios of the two main $\pi^0$ decay modes:
$\mathcal{B}(\pi^0\to\gamma\gamma)=98.8131(6)\,\%$ and $\mathcal{B}(\pi^0\to
e^+e^-\gamma(\gamma))=1.1836(6)\,\%$. Furthermore, we present the complete set
of radiative corrections to the Dalitz decays
$\eta^{(\prime)}\to\ell^+\ell^-\gamma$ beyond the soft-photon approximation,
i.e. over the whole range of the Dalitz plot and with no restrictions on the
energy of a radiative photon. The corrections inevitably depend on the
$\eta^{(\prime)}\to\gamma^*\gamma^{(*)}$ transition form factors. For the
singly-virtual transition form factor appearing e.g. in the bremsstrahlung
correction, recent dispersive calculations are used. For the
one-photon-irreducible contribution at the one-loop level (for the
doubly-virtual form factor), we use a vector-meson-dominance-inspired model
while taking into account the $\eta$-$\eta^{\prime}$ mixing.
| [
{
"created": "Thu, 29 Nov 2018 17:56:09 GMT",
"version": "v1"
}
] | 2019-02-20 | [
[
"Husek",
"Tomáš",
""
]
] | We briefly summarize current experimental and theoretical results on the two important processes of the low-energy hadron physics involving neutral pions, the rare decay $\pi^0\to e^+e^-$ and the Dalitz decay of $\pi^0$, and provide a new value for the ratio $R={\Gamma(\pi^0\to e^+e^-\gamma(\gamma))}/{\Gamma(\pi^0\to\gamma\gamma)}=11.978(6)\times10^{-3}$, which is by two orders of magnitude more precise than the current PDG average. This value is obtained using the complete set of the next-to-leading-order radiative corrections in the QED sector, and incorporates up-to-date values of the $\pi^0$-transition-form-factor slope. The ratio $R$ translates into the branching ratios of the two main $\pi^0$ decay modes: $\mathcal{B}(\pi^0\to\gamma\gamma)=98.8131(6)\,\%$ and $\mathcal{B}(\pi^0\to e^+e^-\gamma(\gamma))=1.1836(6)\,\%$. Furthermore, we present the complete set of radiative corrections to the Dalitz decays $\eta^{(\prime)}\to\ell^+\ell^-\gamma$ beyond the soft-photon approximation, i.e. over the whole range of the Dalitz plot and with no restrictions on the energy of a radiative photon. The corrections inevitably depend on the $\eta^{(\prime)}\to\gamma^*\gamma^{(*)}$ transition form factors. For the singly-virtual transition form factor appearing e.g. in the bremsstrahlung correction, recent dispersive calculations are used. For the one-photon-irreducible contribution at the one-loop level (for the doubly-virtual form factor), we use a vector-meson-dominance-inspired model while taking into account the $\eta$-$\eta^{\prime}$ mixing. |
1305.4020 | Utpal Chattopadhyay | Biplob Bhattacherjee (Kavli IPMU, Japan), Manimala Chakraborti (IACS,
India), Amit Chakraborty (IACS, India), Utpal Chattopadhyay (IACS, India),
Debottam Das (Wurzburg, Germany), Dilip Kumar Ghosh (IACS, India) | Implications of 98 GeV and 125 GeV Higgs scenario in non-decoupling SUSY
with updated ATLAS, CMS and PLANCK data | 34 pages, 9 Figures, pdfLaTex | null | 10.1103/PhysRevD.88.035011 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss both MSSM and NMSSM scenarios in which the lightest Higgs boson
with $m_h=98$~GeV is consistent with the small excess ($\sim 2.3 \sigma$)
observed at the LEP in $e^+ e^-\rightarrow Zh$, with $h \rightarrow b {\bar b}$
process and the heavier Higgs boson of mass close to 125~GeV as the observed
candidate of the SM Higgs like particle at the LHC. We show the allowed regions
in the non-decoupling Higgs zone of MSSM parameter space which are consistent
with several low energy constraints coming from heavy flavour physics, latest
experimental data on Higgs signals and lower limit on superparticle masses from
7~TeV and 8~TeV LHC run. We also implement the constraints from the relic
density of the cold dark matter as obtained from the recent PLANCK data.
Additionally, we discuss the possibility of observing the light Higgs boson of
mass 98~GeV at the 14~TeV LHC run via $pp \rightarrow V h$, with $h \rightarrow
b \bar b$ using the technique of jet substructure. Our analysis shows that at
14~TeV LHC run with 300 ${\rm fb}^{-1}$ luminosity the signal efficiency of
such a light Higgs boson is at most 2.5$\sigma$. Finally, we make a comment on
the prospect of proposed $e^+ e^-$ ILC to discover/exclude this light Higgs
boson.
| [
{
"created": "Fri, 17 May 2013 09:19:37 GMT",
"version": "v1"
}
] | 2013-08-14 | [
[
"Bhattacherjee",
"Biplob",
"",
"Kavli IPMU, Japan"
],
[
"Chakraborti",
"Manimala",
"",
"IACS,\n India"
],
[
"Chakraborty",
"Amit",
"",
"IACS, India"
],
[
"Chattopadhyay",
"Utpal",
"",
"IACS, India"
],
[
"Das",
"Debottam",
... | We discuss both MSSM and NMSSM scenarios in which the lightest Higgs boson with $m_h=98$~GeV is consistent with the small excess ($\sim 2.3 \sigma$) observed at the LEP in $e^+ e^-\rightarrow Zh$, with $h \rightarrow b {\bar b}$ process and the heavier Higgs boson of mass close to 125~GeV as the observed candidate of the SM Higgs like particle at the LHC. We show the allowed regions in the non-decoupling Higgs zone of MSSM parameter space which are consistent with several low energy constraints coming from heavy flavour physics, latest experimental data on Higgs signals and lower limit on superparticle masses from 7~TeV and 8~TeV LHC run. We also implement the constraints from the relic density of the cold dark matter as obtained from the recent PLANCK data. Additionally, we discuss the possibility of observing the light Higgs boson of mass 98~GeV at the 14~TeV LHC run via $pp \rightarrow V h$, with $h \rightarrow b \bar b$ using the technique of jet substructure. Our analysis shows that at 14~TeV LHC run with 300 ${\rm fb}^{-1}$ luminosity the signal efficiency of such a light Higgs boson is at most 2.5$\sigma$. Finally, we make a comment on the prospect of proposed $e^+ e^-$ ILC to discover/exclude this light Higgs boson. |
hep-ph/9302232 | Evan Reidell | M. Burkardt and R. L. Jaffe | Polarized $q\to\Lambda$ Fragmentation Functions from
$e^+e^-\to\Lambda+X^*$ | 10 pages, MIT PREPRINT CTP#2186 | Phys.Rev.Lett. 70 (1993) 2537-2540 | 10.1103/PhysRevLett.70.2537 | null | hep-ph | null | Measurement of the helicity asymmetric cross section for semi-inclusive
production of $\Lambda$-hyperons in $e^+e^-$ annihilation near the $Z^0$
resonance allows a complete determination of the spin-dependent fragmentation
functions for the different quark flavors into the $\Lambda$. The parity
violating, self analyzing, decay of the final state $\Lambda$ makes the
experimental analysis of the helicity asymmetry possible. This experiment
should be practical with present day technology at the LEP collider at CERN or
at SLC at SLAC.
| [
{
"created": "Mon, 8 Feb 1993 14:07:44 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Burkardt",
"M.",
""
],
[
"Jaffe",
"R. L.",
""
]
] | Measurement of the helicity asymmetric cross section for semi-inclusive production of $\Lambda$-hyperons in $e^+e^-$ annihilation near the $Z^0$ resonance allows a complete determination of the spin-dependent fragmentation functions for the different quark flavors into the $\Lambda$. The parity violating, self analyzing, decay of the final state $\Lambda$ makes the experimental analysis of the helicity asymmetry possible. This experiment should be practical with present day technology at the LEP collider at CERN or at SLC at SLAC. |
1612.05170 | Anatoly Radyushkin | Anatoly Radyushkin | Nonperturbative Evolution of Parton Quasi-Distributions | Version to appear in Physics Letters B | null | 10.1016/j.physletb.2017.02.019 | JLAB-THY-16-2406 | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using our formalism of parton virtuality distribution functions (VDFs) we
establish a connection between the transverse momentum dependent distributions
(TMDs) ${\cal F} (x, k_\perp^2)$ and quasi-distributions $Q(y,P_z)$ introduced
recently by X. Ji for lattice QCD extraction of parton distributions $f(x)$. We
build models for PQDs from the VDF-based models for soft TMDs, and analyze the
$P_z$ dependence of the resulting PQDs. We observe a strong nonperturbative
evolution of PQDs for small and moderately large values of $P_z$ reflecting the
transverse momentum dependence of TMDs. Thus, the study of PQDs on the lattice
in the domain of strong nonperturbative effects opens a new perspective for
investigation of the 3-dimensional hadron structure.
| [
{
"created": "Thu, 15 Dec 2016 18:01:47 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Dec 2016 17:52:18 GMT",
"version": "v2"
},
{
"created": "Wed, 8 Feb 2017 15:30:37 GMT",
"version": "v3"
}
] | 2017-02-15 | [
[
"Radyushkin",
"Anatoly",
""
]
] | Using our formalism of parton virtuality distribution functions (VDFs) we establish a connection between the transverse momentum dependent distributions (TMDs) ${\cal F} (x, k_\perp^2)$ and quasi-distributions $Q(y,P_z)$ introduced recently by X. Ji for lattice QCD extraction of parton distributions $f(x)$. We build models for PQDs from the VDF-based models for soft TMDs, and analyze the $P_z$ dependence of the resulting PQDs. We observe a strong nonperturbative evolution of PQDs for small and moderately large values of $P_z$ reflecting the transverse momentum dependence of TMDs. Thus, the study of PQDs on the lattice in the domain of strong nonperturbative effects opens a new perspective for investigation of the 3-dimensional hadron structure. |
1905.13198 | Peter Stoffer | Martin Hoferichter, Peter Stoffer | Dispersion relations for $\gamma^*\gamma^*\to\pi\pi$: helicity
amplitudes, subtractions, and anomalous thresholds | 32 pages, 5 figures; version published in JHEP | JHEP 1907 (2019) 073 | 10.1007/JHEP07(2019)073 | INT-PUB-19-023 | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a comprehensive analysis of the dispersion relations for the
doubly-virtual process $\gamma^*\gamma^*\to\pi\pi$. Starting from the
Bardeen-Tung-Tarrach amplitudes, we first derive the kernel functions that
define the system of Roy-Steiner equations for the partial-wave helicity
amplitudes. We then formulate the solution of these partial-wave dispersion
relations in terms of Omn\`es functions, with special attention paid to the
role of subtraction constants as critical for the application to hadronic
light-by-light scattering. In particular, we explain for the first time why for
some amplitudes the standard Muskhelishvili-Omn\`es solution applies, while for
others a modified approach based on their left-hand cut is required unless
subtractions are introduced. In the doubly-virtual case, the analytic structure
of the vector-resonance partial waves then gives rise to anomalous thresholds,
even for space-like virtualities. We develop a strategy to account for these
effects in the numerical solution, illustrated in terms of the $D$-waves in
$\gamma^*\gamma^*\to\pi\pi$, which allows us to predict the doubly-virtual
responses of the $f_2(1270)$ resonance. In general, our results form the basis
for the incorporation of two-meson intermediate states into hadronic
light-by-light scattering beyond the $S$-wave contribution.
| [
{
"created": "Thu, 30 May 2019 17:37:58 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Jul 2019 17:39:29 GMT",
"version": "v2"
}
] | 2019-07-17 | [
[
"Hoferichter",
"Martin",
""
],
[
"Stoffer",
"Peter",
""
]
] | We present a comprehensive analysis of the dispersion relations for the doubly-virtual process $\gamma^*\gamma^*\to\pi\pi$. Starting from the Bardeen-Tung-Tarrach amplitudes, we first derive the kernel functions that define the system of Roy-Steiner equations for the partial-wave helicity amplitudes. We then formulate the solution of these partial-wave dispersion relations in terms of Omn\`es functions, with special attention paid to the role of subtraction constants as critical for the application to hadronic light-by-light scattering. In particular, we explain for the first time why for some amplitudes the standard Muskhelishvili-Omn\`es solution applies, while for others a modified approach based on their left-hand cut is required unless subtractions are introduced. In the doubly-virtual case, the analytic structure of the vector-resonance partial waves then gives rise to anomalous thresholds, even for space-like virtualities. We develop a strategy to account for these effects in the numerical solution, illustrated in terms of the $D$-waves in $\gamma^*\gamma^*\to\pi\pi$, which allows us to predict the doubly-virtual responses of the $f_2(1270)$ resonance. In general, our results form the basis for the incorporation of two-meson intermediate states into hadronic light-by-light scattering beyond the $S$-wave contribution. |
hep-ph/9603344 | Michael Tung | Michael M. Tung (Dept. de Fisica Teorica, Universidad de Valencia,
Spain) | Dynamical O(alpha_s) Effects in Forward-Backward Asymmetries of Heavy
Quarks | 13 pages (LaTeX), 7 figures + 4 tables (PostScript) | null | null | FTUV/9567, IFIC/95-70, March 1996 | hep-ph | null | We examine the O(alpha_s) forward-backward asymmetries for the production
process e+ e- --> gamma,Z --> q qbar (g), tagging the outgoing heavy-quark jet
at center-of-momentum energies off the Z-peak. The complicated analytic results
are reduced to simple polynomial forms that provide excellent approximations.
For charm and bottom quark, a full dynamical cancellation gives O(alpha_s)
zeros in the forward-backward asymmetry close to the Z-peak. We conclude with a
detailed numerical analysis of our results.
| [
{
"created": "Tue, 19 Mar 1996 15:42:34 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Tung",
"Michael M.",
"",
"Dept. de Fisica Teorica, Universidad de Valencia,\n Spain"
]
] | We examine the O(alpha_s) forward-backward asymmetries for the production process e+ e- --> gamma,Z --> q qbar (g), tagging the outgoing heavy-quark jet at center-of-momentum energies off the Z-peak. The complicated analytic results are reduced to simple polynomial forms that provide excellent approximations. For charm and bottom quark, a full dynamical cancellation gives O(alpha_s) zeros in the forward-backward asymmetry close to the Z-peak. We conclude with a detailed numerical analysis of our results. |
hep-ph/0311354 | Sergio Palomares-Ruiz | Jose Bernabeu (U. Valencia) and Sergio Palomares-Ruiz (U. Valencia,
UCLA & Vanderbilt U.) | An Appearance-Like Reactor Experiment To Measure Ue3 | 18 pp., 6 figs | JHEP 0402 (2004) 068 | 10.1088/1126-6708/2004/02/068 | FTUV-03-1111, IFIC-03-51 | hep-ph | null | Conventional reactor neutrino experiments are dissapearance experiments, and
thus have less sensitivity to small mixing angles than appearance experiments
do. It has been recently shown that future reactor neutrino experiments
consisiting of a near and far detector are competitive with first-generation
superbeams in order to determine sin^2{2 theta_{13}} down to 10^{-2}. We show
that by using the antineutrino-electron elastic scattering at the near detector
around the configuration where dsigma^{bar{\nu}_e}/dT presents a dynamical
zero, an appearance-like experiment can be simulated, with a sensitivity
comparable to the one achieved with the inverse beta-decay reaction in the far
detector. Thus, the near detector could also be used to look for oscillations.
We present how antineutrino-electron elastic scattering could be properly used
for this purpose allowing that the combination of the measurements in the far
detector and in the near detector would push the sensitivity of the experiment
to a lower value of theta_{13}.
| [
{
"created": "Thu, 27 Nov 2003 02:19:48 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Bernabeu",
"Jose",
"",
"U. Valencia"
],
[
"Palomares-Ruiz",
"Sergio",
"",
"U. Valencia,\n UCLA & Vanderbilt U."
]
] | Conventional reactor neutrino experiments are dissapearance experiments, and thus have less sensitivity to small mixing angles than appearance experiments do. It has been recently shown that future reactor neutrino experiments consisiting of a near and far detector are competitive with first-generation superbeams in order to determine sin^2{2 theta_{13}} down to 10^{-2}. We show that by using the antineutrino-electron elastic scattering at the near detector around the configuration where dsigma^{bar{\nu}_e}/dT presents a dynamical zero, an appearance-like experiment can be simulated, with a sensitivity comparable to the one achieved with the inverse beta-decay reaction in the far detector. Thus, the near detector could also be used to look for oscillations. We present how antineutrino-electron elastic scattering could be properly used for this purpose allowing that the combination of the measurements in the far detector and in the near detector would push the sensitivity of the experiment to a lower value of theta_{13}. |
2009.13213 | Giuseppe Bevilacqua | Giuseppe Bevilacqua | Off-shell effects in $t\bar{t}+\gamma/Z$ production at the LHC | 6 pages, 2 figures. Prepared for the Proceedings of the Eighth Annual
Conference on Large Hadron Collider Physics (LHCP2020), 25-30 May 2020 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present state-of-the-art predictions for $t\bar{t}\gamma$ and $t\bar{t}Z(Z
\to \nu_\ell\bar{\nu}_\ell)$ production in the fully leptonic channel at the
LHC. The first process can provide key information on the strength and
structure of the top-quark coupling to the photon. The invisible-decay channel
$t\bar{t}Z(Z \to \nu_\ell\bar{\nu}_\ell)$ is an important SM background for
Dark Matter searches in $t\bar{t}+E_{T}^{miss}$ final states. Our results are
accurate to NLO in QCD and include all resonant and non-resonant diagrams,
interferences and off-shell effects for top quarks and $W/Z$ bosons. As such,
they represent the most complete description of these processes from the
viewpoint of a fixed-order calculation. We show selected results for the LHC
Run II energy of 13 TeV, focusing on the impact of choosing well motivated
scales and on the effect of using different approaches for the modeling of top
quark decays.
| [
{
"created": "Mon, 28 Sep 2020 10:59:14 GMT",
"version": "v1"
}
] | 2020-09-29 | [
[
"Bevilacqua",
"Giuseppe",
""
]
] | We present state-of-the-art predictions for $t\bar{t}\gamma$ and $t\bar{t}Z(Z \to \nu_\ell\bar{\nu}_\ell)$ production in the fully leptonic channel at the LHC. The first process can provide key information on the strength and structure of the top-quark coupling to the photon. The invisible-decay channel $t\bar{t}Z(Z \to \nu_\ell\bar{\nu}_\ell)$ is an important SM background for Dark Matter searches in $t\bar{t}+E_{T}^{miss}$ final states. Our results are accurate to NLO in QCD and include all resonant and non-resonant diagrams, interferences and off-shell effects for top quarks and $W/Z$ bosons. As such, they represent the most complete description of these processes from the viewpoint of a fixed-order calculation. We show selected results for the LHC Run II energy of 13 TeV, focusing on the impact of choosing well motivated scales and on the effect of using different approaches for the modeling of top quark decays. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.