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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1603.09619 | Monoranjan Guchait | Rajdeep M Chatterjee, Monoranjan Guchait, Ringaile Placakyte | A QCD analysis of CMS inclusive differential Z production data at
sqrt(s) = 8 TeV | 9 pages, 5 figures | Phys. Rev. D 94, 034035 (2016) | 10.1103/PhysRevD.94.034035 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The parton distribution functions (PDFs) of the proton are one of the
essential ingredients to describe physics processes at hadron colliders. The Z
boson production data at the LHC have a potential to constrain PDFs, especially
the gluon distribution. In this study the CMS measurement of the inclusive
double differential Z boson production cross section in terms of transverse
momentum and rapidity are compared to the next-to-leading order theory
predictions at the center-of-mass energy of sqrt(s)=8 TeV with an integrated
luminosity of 19.71 inverse femtobarns. In addition, the sensitivity of this
measurement to PDFs is studied within the framework of the HERAFitter. A
moderate improvement to the gluon distribution is observed at the Bjorken x ~
0.1 region. However, in order to obtain further improvement to the gluon
distribution in the global fits, the higher-order theory calculations
accessible via fast techniques are necessary.
| [
{
"created": "Thu, 31 Mar 2016 14:58:55 GMT",
"version": "v1"
}
] | 2016-08-31 | [
[
"Chatterjee",
"Rajdeep M",
""
],
[
"Guchait",
"Monoranjan",
""
],
[
"Placakyte",
"Ringaile",
""
]
] | The parton distribution functions (PDFs) of the proton are one of the essential ingredients to describe physics processes at hadron colliders. The Z boson production data at the LHC have a potential to constrain PDFs, especially the gluon distribution. In this study the CMS measurement of the inclusive double differential Z boson production cross section in terms of transverse momentum and rapidity are compared to the next-to-leading order theory predictions at the center-of-mass energy of sqrt(s)=8 TeV with an integrated luminosity of 19.71 inverse femtobarns. In addition, the sensitivity of this measurement to PDFs is studied within the framework of the HERAFitter. A moderate improvement to the gluon distribution is observed at the Bjorken x ~ 0.1 region. However, in order to obtain further improvement to the gluon distribution in the global fits, the higher-order theory calculations accessible via fast techniques are necessary. |
0805.2137 | Marc Schlegel | S. Arnold, A. V. Efremov, K. Goeke, M. Schlegel, P. Schweitzer | Sivers effect at Hermes, Compass and Clas12 | 20 pages, 8 figures. Prepared for the CLAS 12 RICH Detector Workshop,
January 28-29, 2008, Jefferson Lab, Newport News, VA, USA | null | null | JLAB-THY-08-820 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Single spin asymmetries in semi-inclusive deep-inelastic scattering off
transversely polarized targets give information on, among other fascinating
effects, a pseudo time-reversal odd parton distribution function, the 'Sivers
function'. In this proceeding we review the extractions of this function from
HERMES and COMPASS data. In particular, the HERMES pion and kaon data suggest
significant sea-quarks contributions at $x \simeq 0.15$ to the Sivers effect.
We present a new fit that includes all relevant sea quark distributions and
gives a statistically satisfactory overall description of the data, but does
not describe ideally the $K^+$ data from HERMES. We argue that measurements of
the pion- and kaon Sivers effect at CLAS12, and COMPASS, will clarify the
situation.
| [
{
"created": "Wed, 14 May 2008 19:14:39 GMT",
"version": "v1"
}
] | 2009-09-29 | [
[
"Arnold",
"S.",
""
],
[
"Efremov",
"A. V.",
""
],
[
"Goeke",
"K.",
""
],
[
"Schlegel",
"M.",
""
],
[
"Schweitzer",
"P.",
""
]
] | Single spin asymmetries in semi-inclusive deep-inelastic scattering off transversely polarized targets give information on, among other fascinating effects, a pseudo time-reversal odd parton distribution function, the 'Sivers function'. In this proceeding we review the extractions of this function from HERMES and COMPASS data. In particular, the HERMES pion and kaon data suggest significant sea-quarks contributions at $x \simeq 0.15$ to the Sivers effect. We present a new fit that includes all relevant sea quark distributions and gives a statistically satisfactory overall description of the data, but does not describe ideally the $K^+$ data from HERMES. We argue that measurements of the pion- and kaon Sivers effect at CLAS12, and COMPASS, will clarify the situation. |
1305.6352 | Koichi Yamawaki | Koichi Yamawaki | Discovering Walking Technicolor at LHC and Lattice | 8 pages, 4 figures, Talk given at Rencontres de Moriond 2013 EW,
March 2-9, 2013. To appear in the Proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Walking technicolor, having a large anomalous dimension $\gamma_m \simeq 1$
and approximate scale symmetry, predicts Technidilaton, a light composite Higgs
as a pseudo-Nambu-Goldstone boson of the approximate scale symmetry, which can
be identified with the 125 GeV boson discovered at LHC. I will describe how
such a {\it weakly coupled light composite scalar} can be dynamically realized
in the {\it strongly coupled dynamics}, and can be fit to the current data at
LHC, based on the ladder-like computation and the holographic one. I will also
present results of our lattice collaboration (LatKMI Collaboration) searching
for a walking theory and a light flavor-singlet scalar bound state in large
$N_f$ QCD.
| [
{
"created": "Tue, 28 May 2013 02:34:30 GMT",
"version": "v1"
}
] | 2013-05-29 | [
[
"Yamawaki",
"Koichi",
""
]
] | Walking technicolor, having a large anomalous dimension $\gamma_m \simeq 1$ and approximate scale symmetry, predicts Technidilaton, a light composite Higgs as a pseudo-Nambu-Goldstone boson of the approximate scale symmetry, which can be identified with the 125 GeV boson discovered at LHC. I will describe how such a {\it weakly coupled light composite scalar} can be dynamically realized in the {\it strongly coupled dynamics}, and can be fit to the current data at LHC, based on the ladder-like computation and the holographic one. I will also present results of our lattice collaboration (LatKMI Collaboration) searching for a walking theory and a light flavor-singlet scalar bound state in large $N_f$ QCD. |
0805.3865 | Terekidi | Andrei G. Terekidi, Jurij W. Darewych, Marko Horbatsch | Relativistic corrections to the Zeeman splitting of hyperfine structure
levels in two-fermion bound-state systems | 11 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A relativistic theory of the Zeeman splitting of hyperfine levels in
two-fermion systems is presented. The approach is based on the variational
equation for bound states derived from quantum electrodynamics [1].
Relativistic corrections to the g-factor are obtained up to O(alpha^2).
Calculations are provided for all quantum states and for arbitrary fermionic
mass ratio. In the one-body limit our calculations reproduce the formula for
the g-factor (to O((Z*alpha)^2)) obtained from the Dirac equation. The results
will be useful for comparison with high-precision measurements.
| [
{
"created": "Mon, 26 May 2008 03:11:51 GMT",
"version": "v1"
}
] | 2008-05-27 | [
[
"Terekidi",
"Andrei G.",
""
],
[
"Darewych",
"Jurij W.",
""
],
[
"Horbatsch",
"Marko",
""
]
] | A relativistic theory of the Zeeman splitting of hyperfine levels in two-fermion systems is presented. The approach is based on the variational equation for bound states derived from quantum electrodynamics [1]. Relativistic corrections to the g-factor are obtained up to O(alpha^2). Calculations are provided for all quantum states and for arbitrary fermionic mass ratio. In the one-body limit our calculations reproduce the formula for the g-factor (to O((Z*alpha)^2)) obtained from the Dirac equation. The results will be useful for comparison with high-precision measurements. |
hep-ph/9205223 | Jihn E. Kim | Jihn E. Kim | $\theta$ Bag and Quark Confinement | 12 pages (4 figures not included) | Phys.Lett. B283 (1992) 107-112; Erratum-ibid. B285 (1992) 400 | 10.1016/0370-2693(92)91436-D | null | hep-ph | null | We propose $\theta$ bag through the wall separating $\theta=0$ and
$\theta=\pi$. $\theta$ may or may not be a dynamical field generating the wall.
For a massive pseudo scalar $\theta$, we present a two Higgs doublet model. We
also presnt an idea for quark confinement within this $\theta$ bag scheme.
| [
{
"created": "Mon, 18 May 1992 14:36:18 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Kim",
"Jihn E.",
""
]
] | We propose $\theta$ bag through the wall separating $\theta=0$ and $\theta=\pi$. $\theta$ may or may not be a dynamical field generating the wall. For a massive pseudo scalar $\theta$, we present a two Higgs doublet model. We also presnt an idea for quark confinement within this $\theta$ bag scheme. |
hep-ph/9903307 | Francois Gelis | Patrick Aurenche (LAPTH, Annecy), Francois Gelis (LAPTH, Annecy),
Randy Kobes (Winnipeg Univ), Haitham Zaraket (LAPTH, Annecy) | Two-loop Compton and annihilation processes in thermal QCD | Latex, 24 pages, postscript figures included with the package
graphics | Phys.Rev. D60 (1999) 076002 | 10.1103/PhysRevD.60.076002 | LAPTH-719/99, WIN-99/02 | hep-ph | null | We calculate the Compton and annihilation production of a soft static lepton
pair in a quark-gluon plasma in the two-loop approximation. We work in the
context of the effective perturbative expansion based on the resummation of
hard thermal loops. Double counting is avoided by subtracting appropriate
counterterms. It is found that the two-loop diagrams give contributions of the
same order as the one-loop diagram. Furthermore, these contributions are
necessary to obtain agreement with the naive perturbative expansion in the
limit of vanishing thermal masses.
| [
{
"created": "Wed, 10 Mar 1999 10:40:46 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Aurenche",
"Patrick",
"",
"LAPTH, Annecy"
],
[
"Gelis",
"Francois",
"",
"LAPTH, Annecy"
],
[
"Kobes",
"Randy",
"",
"Winnipeg Univ"
],
[
"Zaraket",
"Haitham",
"",
"LAPTH, Annecy"
]
] | We calculate the Compton and annihilation production of a soft static lepton pair in a quark-gluon plasma in the two-loop approximation. We work in the context of the effective perturbative expansion based on the resummation of hard thermal loops. Double counting is avoided by subtracting appropriate counterterms. It is found that the two-loop diagrams give contributions of the same order as the one-loop diagram. Furthermore, these contributions are necessary to obtain agreement with the naive perturbative expansion in the limit of vanishing thermal masses. |
1712.05342 | Philip Ilten | Lucian Harland-Lang, Philip Ilten, and Jan Kretzschmar | WG1: Structure Functions and Parton Densities | 16 pages, 10 figures, to appear in the proceedings of the 25th
International Workshop on Deep Inelastic Scattering and Related Topics (DIS
2017), 3-7 April 2017, University of Birmingham, UK | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This paper gives a summary of selected highlights discussed in the working
group on "Structure Functions and Parton Densities" (WG1) at the DIS 2017
conference. From the many talks presented we extract some general themes
discussed with respect to global PDF fits, new PDF-sensitive measurements from
the LHC experiments and elsewhere, exploitation of new ideas, tools to perform
PDF fits, PDFs of heavy nuclei, and finally progress in basic theory
calculations.
| [
{
"created": "Thu, 14 Dec 2017 17:10:46 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Jan 2018 11:58:24 GMT",
"version": "v2"
}
] | 2018-01-09 | [
[
"Harland-Lang",
"Lucian",
""
],
[
"Ilten",
"Philip",
""
],
[
"Kretzschmar",
"Jan",
""
]
] | This paper gives a summary of selected highlights discussed in the working group on "Structure Functions and Parton Densities" (WG1) at the DIS 2017 conference. From the many talks presented we extract some general themes discussed with respect to global PDF fits, new PDF-sensitive measurements from the LHC experiments and elsewhere, exploitation of new ideas, tools to perform PDF fits, PDFs of heavy nuclei, and finally progress in basic theory calculations. |
hep-ph/9811245 | B. F. L. Ward | B. F. L. Ward (1), S. Jadach (1 and 2), M. Melles (1 and 3) and S. A.
Yost (1) ((1) Department of Physics, University of Tennessee, Knoxville,
Tennessee, (2) Institute of Nuclear Physics, Cracow, Poland, (3) Department
of Theoretical Physics, University of Durham, Durham, England) | New Results on the Theoretical Precision of the LEP/SLC Luminosity | 4 pages, 3 figures, 1 table, 1998 Rochester Conference presentation,
corrected Ref. 12, improved reference to Ref. 10, corrected Ref. 13 | Phys.Lett. B450 (1999) 262-266 | 10.1016/S0370-2693(99)00104-5 | UTHEP-98-0501 | hep-ph | null | We consider the error budget for the calculation of the LEP/SLC luminosity in
the Monte Carlo event generator BHLUMI4.04 from the standpoint of new
calculations of the exact result for the O(alpha) correction to the process e+
e- -> e+ e- + gamma in the low angle luminosity regime at SLC/LEP energies, for
the double bremsstrahlung effect e+ e- -> e+ e- + gamma gamma in this regime,
and for the size of the two-loop virtual correction to e+ e- -> e+ e- in this
regime in context of Yennie-Frautschi-Suura exponentiation. We find that the
error on the O(alpha**2) photonic correction can be reduced from the currently
published value 0.1% to the value 0.027%. This leads to an over-all precision
tag for the currently available program BHLUMI4.04 of 0.061%. This reduction of
the precision of the calculation is important for the final LEP1 EW precision Z
physics tests of the Standard Model.
| [
{
"created": "Wed, 4 Nov 1998 19:48:50 GMT",
"version": "v1"
},
{
"created": "Wed, 18 Nov 1998 19:06:15 GMT",
"version": "v2"
},
{
"created": "Tue, 12 Jan 1999 13:54:30 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Ward",
"B. F. L.",
"",
"1 and 2"
],
[
"Jadach",
"S.",
"",
"1 and 2"
],
[
"Melles",
"M.",
"",
"1 and 3"
],
[
"Yost",
"S. A.",
""
]
] | We consider the error budget for the calculation of the LEP/SLC luminosity in the Monte Carlo event generator BHLUMI4.04 from the standpoint of new calculations of the exact result for the O(alpha) correction to the process e+ e- -> e+ e- + gamma in the low angle luminosity regime at SLC/LEP energies, for the double bremsstrahlung effect e+ e- -> e+ e- + gamma gamma in this regime, and for the size of the two-loop virtual correction to e+ e- -> e+ e- in this regime in context of Yennie-Frautschi-Suura exponentiation. We find that the error on the O(alpha**2) photonic correction can be reduced from the currently published value 0.1% to the value 0.027%. This leads to an over-all precision tag for the currently available program BHLUMI4.04 of 0.061%. This reduction of the precision of the calculation is important for the final LEP1 EW precision Z physics tests of the Standard Model. |
hep-ph/0004054 | Kresimir Kumericki | D. Klabucar, K. Kumericki, B. Melic and I. Picek | Nucleon strangeness as the response to a strangeness-sensitive probe in
a class of hadron models | LaTeX2e, 34 pages, 4 figures (included) | Fizika B8 (1999) 505-534 | null | ZTF-99/09 | hep-ph | null | On top of its valence quarks, the full nucleon ground state may contain
appreciable admixture of s-\bar{s} pairs already at small momentum transfers.
This paper discusses strangeness in the mean-field type of nucleon models, and
exemplifies this by explicit calculations in the MIT bag model enriched by the
presence of instantons.
We calculate the instanton contribution to the strangeness in the MIT bag (on
top of the standard contribution to strangeness found in that model). Although
we do it in an essentially perturbative way, we present a detailed derivation
of the formula expressing nucleon matrix elements of bilinear strange quark
operators, in terms of a model valence nucleon state and interactions producing
quark-antiquark fluctuations on top of that valence state. We do it in detail
to clarify our argument that in the context of the mean-field type of quark
models (where a Fock state expansion exists and where the nucleon state can be
constructed out of single-quark states), the resulting formula acquires a
significance beyond perturbation theory.The derivation combines the usage of
the evolution operator containing a strangeness source, and Feynman-Hellmann
theorem.
| [
{
"created": "Thu, 6 Apr 2000 14:06:54 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Klabucar",
"D.",
""
],
[
"Kumericki",
"K.",
""
],
[
"Melic",
"B.",
""
],
[
"Picek",
"I.",
""
]
] | On top of its valence quarks, the full nucleon ground state may contain appreciable admixture of s-\bar{s} pairs already at small momentum transfers. This paper discusses strangeness in the mean-field type of nucleon models, and exemplifies this by explicit calculations in the MIT bag model enriched by the presence of instantons. We calculate the instanton contribution to the strangeness in the MIT bag (on top of the standard contribution to strangeness found in that model). Although we do it in an essentially perturbative way, we present a detailed derivation of the formula expressing nucleon matrix elements of bilinear strange quark operators, in terms of a model valence nucleon state and interactions producing quark-antiquark fluctuations on top of that valence state. We do it in detail to clarify our argument that in the context of the mean-field type of quark models (where a Fock state expansion exists and where the nucleon state can be constructed out of single-quark states), the resulting formula acquires a significance beyond perturbation theory.The derivation combines the usage of the evolution operator containing a strangeness source, and Feynman-Hellmann theorem. |
1201.0485 | Marek Gazdzicki | M. Gazdzicki | On the history of multi-particle production in high energy collisions | 12 pages, 9 figures, invited talk at Strangeness in Quark Matter
2011, Krakow, Poland | Acta Physica Polonica B vol. 43 (2012) page 791 | 10.5506/APhysPolB.43.791 | null | hep-ph hep-ex nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The 60th birthday of Johann Rafelski was celebrated during the Strangeness in
Quark Matter 2011 in Krakow. Johann was born in Krakow and he initiated the
series of the SQM conferences. This report, which briefly presents my personal
view on a history of multi-particle production in high energy collisions, is
dedicated to Johann.
| [
{
"created": "Mon, 2 Jan 2012 16:18:55 GMT",
"version": "v1"
}
] | 2012-05-09 | [
[
"Gazdzicki",
"M.",
""
]
] | The 60th birthday of Johann Rafelski was celebrated during the Strangeness in Quark Matter 2011 in Krakow. Johann was born in Krakow and he initiated the series of the SQM conferences. This report, which briefly presents my personal view on a history of multi-particle production in high energy collisions, is dedicated to Johann. |
1402.1328 | Enrico Maria Sessolo | Kamila Kowalska, Leszek Roszkowski, Enrico Maria Sessolo, Sebastian
Trojanowski | Low fine tuning in the MSSM with higgsino dark matter and unification
constraints | 35 pages, 8 figures. Figure 2 added, minor changes. Version published
in JHEP | JHEP 1404 (2014) 166 | 10.1007/JHEP04(2014)166 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the issue of fine tuning in the MSSM with GUT-scale boundary
conditions. We identify specific unification patterns and mass relations that
can lead to a significant lowering of the fine tuning due to gauginos, scalars,
and the \mu\ parameter, relative to the simplest unification conditions. We
focus on a phenomenologically interesting region that is favored by the Higgs
mass and the relic density where the dark matter is a nearly pure higgsino with
mass given by \mu~1 TeV while the scalars and gauginos have masses in the
multi-TeV regime. There, we find that the fine tuning can be reduced to the
level of a few percent. Despite the gluino mass in the ballpark of 2 TeV,
resulting mass spectra will be hard to explore at the LHC, but good prospects
for detection come from dark matter direct detection experiments. Finally, we
demonstrate with a specific example how the conditions and mass relations
giving low fine tuning can originate in the context of supergravity and Grand
Unified Theories.
| [
{
"created": "Thu, 6 Feb 2014 11:39:46 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Feb 2014 14:00:16 GMT",
"version": "v2"
},
{
"created": "Thu, 10 Apr 2014 11:15:23 GMT",
"version": "v3"
}
] | 2014-05-05 | [
[
"Kowalska",
"Kamila",
""
],
[
"Roszkowski",
"Leszek",
""
],
[
"Sessolo",
"Enrico Maria",
""
],
[
"Trojanowski",
"Sebastian",
""
]
] | We examine the issue of fine tuning in the MSSM with GUT-scale boundary conditions. We identify specific unification patterns and mass relations that can lead to a significant lowering of the fine tuning due to gauginos, scalars, and the \mu\ parameter, relative to the simplest unification conditions. We focus on a phenomenologically interesting region that is favored by the Higgs mass and the relic density where the dark matter is a nearly pure higgsino with mass given by \mu~1 TeV while the scalars and gauginos have masses in the multi-TeV regime. There, we find that the fine tuning can be reduced to the level of a few percent. Despite the gluino mass in the ballpark of 2 TeV, resulting mass spectra will be hard to explore at the LHC, but good prospects for detection come from dark matter direct detection experiments. Finally, we demonstrate with a specific example how the conditions and mass relations giving low fine tuning can originate in the context of supergravity and Grand Unified Theories. |
1711.05292 | Antonio Onofre | D. Azevedo, A. Onofre, F. Filthaut, R. Gon\c{c}alo | CP tests of Higgs couplings in $t\bar{t}h$ semileptonic events at the
LHC | 12 pages, 5 figures | Phys. Rev. D 98, 033004 (2018) | 10.1103/PhysRevD.98.033004 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The CP nature of the Higgs coupling to top quarks is addressed in this paper,
in single charged lepton final states of $t\bar{t}h$ events produced in
proton-proton collisions at the LHC. Pure scalar ($h=H$) and pseudo-scalar
($h=A$) Higgs boson signal events, generated with MadGraph5_aMC@NLO, are fully
reconstructed using a kinematic fit. Angular distributions of the decay
products, as well as CP-sensitive asymmetries, are exploited to separate and
gain sensitivity to possible pseudo-scalar components of the Higgs boson and
reduce the contribution from the dominant irreducible background
$t\bar{t}b\bar{b}$. Significant differences are found between the pure CP-even
and -odd signal hypotheses as well as with respect to the Standard Model
background, in particular the $t\bar{t} b\bar{b}$ contribution. Such
differences survive the event reconstruction, allowing to define optimal
observables to extract the Higgs couplings parameters from a global fit. A
dedicated analysis is applied to efficiently identify signal events and reject
as much as possible the expected Standard Model background. The results
obtained are compared with a similar analysis in the dilepton channel. We show
that the single lepton channel is more promising overall and can be used in
combination to study the CP nature of the Higgs coupling to top quarks.
| [
{
"created": "Tue, 14 Nov 2017 19:38:33 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jun 2018 21:47:45 GMT",
"version": "v2"
}
] | 2018-08-29 | [
[
"Azevedo",
"D.",
""
],
[
"Onofre",
"A.",
""
],
[
"Filthaut",
"F.",
""
],
[
"Gonçalo",
"R.",
""
]
] | The CP nature of the Higgs coupling to top quarks is addressed in this paper, in single charged lepton final states of $t\bar{t}h$ events produced in proton-proton collisions at the LHC. Pure scalar ($h=H$) and pseudo-scalar ($h=A$) Higgs boson signal events, generated with MadGraph5_aMC@NLO, are fully reconstructed using a kinematic fit. Angular distributions of the decay products, as well as CP-sensitive asymmetries, are exploited to separate and gain sensitivity to possible pseudo-scalar components of the Higgs boson and reduce the contribution from the dominant irreducible background $t\bar{t}b\bar{b}$. Significant differences are found between the pure CP-even and -odd signal hypotheses as well as with respect to the Standard Model background, in particular the $t\bar{t} b\bar{b}$ contribution. Such differences survive the event reconstruction, allowing to define optimal observables to extract the Higgs couplings parameters from a global fit. A dedicated analysis is applied to efficiently identify signal events and reject as much as possible the expected Standard Model background. The results obtained are compared with a similar analysis in the dilepton channel. We show that the single lepton channel is more promising overall and can be used in combination to study the CP nature of the Higgs coupling to top quarks. |
2209.05289 | Francesco Moretti | M. Gorbahn, S. J\"ager, F. Moretti, E. van der Merwe | Semileptonic weak Hamiltonian to $\mathcal{O}(\alpha
\alpha_s(\mu_{\mathrm{Lattice}}))$ in momentum-space subtraction schemes | 1+22 pages | null | 10.1007/JHEP01(2023)159 | null | hep-ph hep-lat | http://creativecommons.org/licenses/by/4.0/ | The CKM unitarity precision test of the Standard Model requires a systematic
treatment of electromagnetic and strong corrections for semi-leptonic decays.
Electromagnetic corrections require the renormalization of a semileptonic
four-fermion operator. In this work we calculate the
$\mathcal{O}(\alpha\alpha_s)$ perturbative scheme conversion between the
$\bar{\rm MS}$ scheme and several momentum-space subtraction schemes, which can
also be implemented on the lattice. We consider schemes defined by MOM and SMOM
kinematics and emphasize the importance of the choice of projector for each
scheme. The conventional projector, that has been used in the literature for
MOM kinematics, generates QCD corrections to the conversion factor that do not
vanish for $\alpha=0$ and which generate an artificial dependence on the
lattice matching scale that would only disappear after summing all orders of
perturbation theory. This can be traced to the violation of a Ward identity
that holds in tha $\alpha =0$ limit. We show how to remedy this by judicious
choices of projector, and prove that the Wilson coefficients in those schemes
are free from pure QCD contributions. The resulting Wilson coefficients (and
operator matrix elements) have greatly reduced scale dependence. Our choice of
the $\bar{\rm MS}$ scheme over the traditional $W$-mass scheme is motivated by
the fact that, besides being more tractable at higher orders, unlike the latter
it allows for a transparent separation of scales. We exploit this to obtain
renormalization-group-improved leading-log and next-to-leading-log strong
corrections to the electromagnetic contributions and study the (QED-induced)
dependence on the lattice matching scale.
| [
{
"created": "Mon, 12 Sep 2022 14:43:44 GMT",
"version": "v1"
},
{
"created": "Fri, 21 Apr 2023 15:30:32 GMT",
"version": "v2"
}
] | 2023-04-24 | [
[
"Gorbahn",
"M.",
""
],
[
"Jäger",
"S.",
""
],
[
"Moretti",
"F.",
""
],
[
"van der Merwe",
"E.",
""
]
] | The CKM unitarity precision test of the Standard Model requires a systematic treatment of electromagnetic and strong corrections for semi-leptonic decays. Electromagnetic corrections require the renormalization of a semileptonic four-fermion operator. In this work we calculate the $\mathcal{O}(\alpha\alpha_s)$ perturbative scheme conversion between the $\bar{\rm MS}$ scheme and several momentum-space subtraction schemes, which can also be implemented on the lattice. We consider schemes defined by MOM and SMOM kinematics and emphasize the importance of the choice of projector for each scheme. The conventional projector, that has been used in the literature for MOM kinematics, generates QCD corrections to the conversion factor that do not vanish for $\alpha=0$ and which generate an artificial dependence on the lattice matching scale that would only disappear after summing all orders of perturbation theory. This can be traced to the violation of a Ward identity that holds in tha $\alpha =0$ limit. We show how to remedy this by judicious choices of projector, and prove that the Wilson coefficients in those schemes are free from pure QCD contributions. The resulting Wilson coefficients (and operator matrix elements) have greatly reduced scale dependence. Our choice of the $\bar{\rm MS}$ scheme over the traditional $W$-mass scheme is motivated by the fact that, besides being more tractable at higher orders, unlike the latter it allows for a transparent separation of scales. We exploit this to obtain renormalization-group-improved leading-log and next-to-leading-log strong corrections to the electromagnetic contributions and study the (QED-induced) dependence on the lattice matching scale. |
hep-ph/0111141 | Alan Kostelecky | Robert Bluhm, Alan Kostelecky, Charles Lane, and Neil Russell | Clock-Comparison Tests of Lorentz and CPT Symmetry in Space | 4 pages | Phys.Rev.Lett.88:090801,2002 | 10.1103/PhysRevLett.88.090801 | IUHET 440, September 2001 | hep-ph hep-th | null | Clock-comparison experiments conducted in space can provide access to many
unmeasured coefficients for Lorentz and CPT violation. The orbital
configuration of a satellite platform and the relatively large velocities
attainable in a deep-space mission would permit a broad range of tests with
Planck-scale sensitivity.
| [
{
"created": "Mon, 12 Nov 2001 18:26:02 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Bluhm",
"Robert",
""
],
[
"Kostelecky",
"Alan",
""
],
[
"Lane",
"Charles",
""
],
[
"Russell",
"Neil",
""
]
] | Clock-comparison experiments conducted in space can provide access to many unmeasured coefficients for Lorentz and CPT violation. The orbital configuration of a satellite platform and the relatively large velocities attainable in a deep-space mission would permit a broad range of tests with Planck-scale sensitivity. |
hep-ph/0110406 | Peter Petreczky | S. Digal, P. Petreczky and H. Satz | Sequential Quarkonium Suppression | Talk presented on the International Workshop on the Physics of the
Quark - Gluon Plasma, September 4-7, 2001, Palaiseau | null | null | null | hep-ph hep-lat | null | We use recent lattice data on the heavy quark potential in order to determine
the dissociation temperatures of different quarkonium states in hot strongly
interacting matter. Our analysis shows in particular that certain quarkonium
states dissociate below the deconfinement point.
| [
{
"created": "Wed, 31 Oct 2001 14:24:34 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Digal",
"S.",
""
],
[
"Petreczky",
"P.",
""
],
[
"Satz",
"H.",
""
]
] | We use recent lattice data on the heavy quark potential in order to determine the dissociation temperatures of different quarkonium states in hot strongly interacting matter. Our analysis shows in particular that certain quarkonium states dissociate below the deconfinement point. |
0802.0762 | Ann E. Nelson | A. E. Nelson and J. Walsh | Chameleon Vector Bosons | 10 pages | Phys.Rev.D77:095006,2008 | 10.1103/PhysRevD.77.095006 | null | hep-ph astro-ph gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that for a force mediated by a vector particle coupled to a conserved
U(1) charge, the apparent range and strength can depend on the size and density
of the source, and the proximity to other sources. This "chameleon" effect is
due to screening from a light charged scalar. Such screening can weaken
astrophysical constraints on new gauge bosons. As an example we consider the
constraints on chameleonic gauged B-L. We show that although Casimir
measurements greatly constrain any B-L force much stronger than gravity with
range longer than 0.1 microns, there remains an experimental window for a long
range chameleonic B-L force. Such a force could be much stronger than gravity,
and long or infinite range in vacuum, but have an effective range near the
surface of the earth which is less than a micron.
| [
{
"created": "Wed, 6 Feb 2008 09:50:44 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Nelson",
"A. E.",
""
],
[
"Walsh",
"J.",
""
]
] | We show that for a force mediated by a vector particle coupled to a conserved U(1) charge, the apparent range and strength can depend on the size and density of the source, and the proximity to other sources. This "chameleon" effect is due to screening from a light charged scalar. Such screening can weaken astrophysical constraints on new gauge bosons. As an example we consider the constraints on chameleonic gauged B-L. We show that although Casimir measurements greatly constrain any B-L force much stronger than gravity with range longer than 0.1 microns, there remains an experimental window for a long range chameleonic B-L force. Such a force could be much stronger than gravity, and long or infinite range in vacuum, but have an effective range near the surface of the earth which is less than a micron. |
2109.08483 | Rong Wang | Gang Xie, Chengdong Han, Rong Wang, Xurong Chen | Tackling the kaon structure function at EicC | 9 pages, 12 figures | null | 10.1088/1674-1137/ac5b0e | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Measuring the kaon structure beyond the proton and pion structures is one of
the hot topics in hadron physics, as it is one way to understand the nature of
Nambu-Goldstone boson of QCD and to see the interplay between the EHM mechanism
and the HB mechanism for hadron mass generation. In this paper, we present a
simulation of the leading $\Lambda$ baryon tagged deep inelastic scattering
experiment at EicC (Electron-ion collider in China), which is engaged to unveil
the internal structure of kaon through Sullivan process. According to our
simulation results, the suggested experiment will cover the kinematical domain
of $0.05\lesssim x_{\rm K} \lesssim 0.85$ and $Q^2$ up to 50 GeV$^2$, with the
acceptable statistical uncertainties. In the relatively low-$Q^2$ region ($<10$
GeV$^2$), the Monte-Carlo simulation shows a good precision of the measurement
($<5$\%) for the kaon structure function $F_2^{\rm K}$. In the high-$Q^2$
region (up to 50 GeV$^2$), the statistical uncertainty of $F_2^{\rm K}$ is also
acceptable ($<10$\%) for the data at $x_{\rm K}<0.8$. To perform such an
experiment at an electron-ion collider, a high-performance zero-degree
calorimeter is required.
| [
{
"created": "Fri, 17 Sep 2021 11:57:26 GMT",
"version": "v1"
}
] | 2022-06-15 | [
[
"Xie",
"Gang",
""
],
[
"Han",
"Chengdong",
""
],
[
"Wang",
"Rong",
""
],
[
"Chen",
"Xurong",
""
]
] | Measuring the kaon structure beyond the proton and pion structures is one of the hot topics in hadron physics, as it is one way to understand the nature of Nambu-Goldstone boson of QCD and to see the interplay between the EHM mechanism and the HB mechanism for hadron mass generation. In this paper, we present a simulation of the leading $\Lambda$ baryon tagged deep inelastic scattering experiment at EicC (Electron-ion collider in China), which is engaged to unveil the internal structure of kaon through Sullivan process. According to our simulation results, the suggested experiment will cover the kinematical domain of $0.05\lesssim x_{\rm K} \lesssim 0.85$ and $Q^2$ up to 50 GeV$^2$, with the acceptable statistical uncertainties. In the relatively low-$Q^2$ region ($<10$ GeV$^2$), the Monte-Carlo simulation shows a good precision of the measurement ($<5$\%) for the kaon structure function $F_2^{\rm K}$. In the high-$Q^2$ region (up to 50 GeV$^2$), the statistical uncertainty of $F_2^{\rm K}$ is also acceptable ($<10$\%) for the data at $x_{\rm K}<0.8$. To perform such an experiment at an electron-ion collider, a high-performance zero-degree calorimeter is required. |
hep-ph/9409294 | null | P. Aurenche, J.-Ph. Guillet M. Fontannaz Y. Shimizu, J. Fujimoto K.
Kato | The production of jets from quasi real photons in \epem collisions | 6 + 8 figures not included available upon request at
(AURENCHE@LAPVAX.IN2P3.FR) , ENSLAPP-A-482/94, KEK CP-019 | null | null | null | hep-ph | null | We consider the production of jets in photon-photon collisions beyond the
leading logarithm approximation. Theoretical uncertainties as well as
uncertainties due to the virtuality of the initial photons are discussed in
detail. The comparison with TOPAZ data is performed and good agreement is found
between experiment and theory. It is expected that future high precision
TRISTAN data will constrain the non-perturbative component of the photon
structure function.
| [
{
"created": "Tue, 13 Sep 1994 09:53:34 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Aurenche",
"P.",
""
],
[
"Shimizu",
"J. -Ph. Guillet M. Fontannaz Y.",
""
],
[
"Kato",
"J. Fujimoto K.",
""
]
] | We consider the production of jets in photon-photon collisions beyond the leading logarithm approximation. Theoretical uncertainties as well as uncertainties due to the virtuality of the initial photons are discussed in detail. The comparison with TOPAZ data is performed and good agreement is found between experiment and theory. It is expected that future high precision TRISTAN data will constrain the non-perturbative component of the photon structure function. |
hep-ph/9307359 | Bob Holdom | B. Holdom | Cosmic balloons | 9 pages, LaTeX, 2 figures in separate file, UPTP-93-18 | Phys.Rev.D49:3844-3846,1994 | 10.1103/PhysRevD.49.3844 | null | hep-ph astro-ph | null | Cosmic balloons, consisting of relativistic particles trapped inside a
spherical domain wall, may be created in the early universe. We calculate the
balloon mass $M$ as a function of the radius $R$ and the energy density
profile, $\rho (r)$, including the effects of gravity. At the maximum balloon
mass $2GM/R\approx 0.52$ for any value of the mass density of the wall.
| [
{
"created": "Wed, 28 Jul 1993 22:59:31 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Dec 1993 22:48:48 GMT",
"version": "v2"
}
] | 2009-12-30 | [
[
"Holdom",
"B.",
""
]
] | Cosmic balloons, consisting of relativistic particles trapped inside a spherical domain wall, may be created in the early universe. We calculate the balloon mass $M$ as a function of the radius $R$ and the energy density profile, $\rho (r)$, including the effects of gravity. At the maximum balloon mass $2GM/R\approx 0.52$ for any value of the mass density of the wall. |
1612.04950 | Xun-Jie Xu | Xun-Jie Xu | Minima of the Scalar Potential in the Type II Seesaw Model: From Local
to Global | 15 pages, 3 figures | Phys.Rev. D94 (2016) no.11, 115025 | 10.1103/PhysRevD.94.115025 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Type II seesaw model requires that its scalar doublet $H$ and triplet
$\Delta$ get specific patterns of VEVs $\langle H\rangle\propto(0,1)^{T}$ and
$\langle\Delta\rangle\propto(0,0,1)^{T}$ to accommodate neutrino masses.
However, other types of minima could also exist in the scalar potential, which
may strongly contradict to experimental observations. This paper studies when
the minimum at $\langle H\rangle\propto(0,1)^{T}$ and
$\langle\Delta\rangle\propto(0,0,1)^{T}$ will be global and finds the necessary
and sufficient condition for that, assuming that the lepton number violating
term $H^{2}\Delta$ in the potential is perturbatively small.
| [
{
"created": "Thu, 15 Dec 2016 07:32:42 GMT",
"version": "v1"
}
] | 2017-01-02 | [
[
"Xu",
"Xun-Jie",
""
]
] | The Type II seesaw model requires that its scalar doublet $H$ and triplet $\Delta$ get specific patterns of VEVs $\langle H\rangle\propto(0,1)^{T}$ and $\langle\Delta\rangle\propto(0,0,1)^{T}$ to accommodate neutrino masses. However, other types of minima could also exist in the scalar potential, which may strongly contradict to experimental observations. This paper studies when the minimum at $\langle H\rangle\propto(0,1)^{T}$ and $\langle\Delta\rangle\propto(0,0,1)^{T}$ will be global and finds the necessary and sufficient condition for that, assuming that the lepton number violating term $H^{2}\Delta$ in the potential is perturbatively small. |
1706.10026 | Suchismita Sahoo | Suchismita Sahoo, Rukmani Mohanta | Study of the rare decays $B_{s,d}^* \to \mu^+ \mu^-$ | 4 Pages, Contribution to the proceedings of XXII DAE-BRNS High Energy
Physics Symposium, University of Delhi, India, Dec. 12-16, 2016 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study rare leptonic decays of vector $B$ mesons in the scalar leptoquark
and family non-universal $Z^\prime$ models. We constrain these new couplings by
using the measured branching fractions of $B_{s,d} \to \mu^+ \mu^-$ processes
and the existing $B_{s,d}^0-\bar B_{s,d}^0$ mixing data. We estimate the
branching fractions of $B_{s,d}^* \to \mu^+ \mu^-$ in both the models, which
are found to be reasonably enhanced from their corresponding standard model
values and within the reach of Run 2-3 of LHC.
| [
{
"created": "Fri, 30 Jun 2017 05:39:20 GMT",
"version": "v1"
}
] | 2017-07-03 | [
[
"Sahoo",
"Suchismita",
""
],
[
"Mohanta",
"Rukmani",
""
]
] | We study rare leptonic decays of vector $B$ mesons in the scalar leptoquark and family non-universal $Z^\prime$ models. We constrain these new couplings by using the measured branching fractions of $B_{s,d} \to \mu^+ \mu^-$ processes and the existing $B_{s,d}^0-\bar B_{s,d}^0$ mixing data. We estimate the branching fractions of $B_{s,d}^* \to \mu^+ \mu^-$ in both the models, which are found to be reasonably enhanced from their corresponding standard model values and within the reach of Run 2-3 of LHC. |
0906.0150 | Sebastian Hollenberg | Sebastian Hollenberg, Octavian Micu, Heinrich P\"as, Thomas J. Weiler | Baseline-dependent neutrino oscillations with extra-dimensional
shortcuts | 20 pages, 5 figures | null | 10.1103/PhysRevD.80.093005 | DO-TH-09/08 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In extra-dimensional scenarios oscillations between active and sterile
neutrinos can be governed by a new resonance in the oscillation amplitude. This
resonance results when cancelation occurs between two phase differences, the
usual kinematic one coming from the neutrino mass-squared difference, and a
geometric one coming from the difference in travel times of the sterile
neutrino through the bulk relative to the active neutrino confined to the
brane. In this work we introduce a specific metric for the brane-bulk system,
from which we explicitly derive extra-dimensional geodesics for the sterile
neutrino, and ultimately the oscillation probability of the active-sterile
two-state system. We find that for an asymmetrically-warped metric, the
resonance condition involves both the neutrino energy E and the travel distance
L on the brane. In other words, the resonant energy may be viewed as
baseline-dependent. We show that to a good approximation, the resonance
condition is not on E or on L, but rather on the product LE. The model is rich
in implications, including the possibility of multiple solutions to the
resonance condition, with ramifications for existing data sets, e.g., LSND and
MiniBooNE. Some phenomenology with these brane-bulk resonances is discussed.
| [
{
"created": "Sun, 31 May 2009 14:29:16 GMT",
"version": "v1"
}
] | 2015-05-13 | [
[
"Hollenberg",
"Sebastian",
""
],
[
"Micu",
"Octavian",
""
],
[
"Päs",
"Heinrich",
""
],
[
"Weiler",
"Thomas J.",
""
]
] | In extra-dimensional scenarios oscillations between active and sterile neutrinos can be governed by a new resonance in the oscillation amplitude. This resonance results when cancelation occurs between two phase differences, the usual kinematic one coming from the neutrino mass-squared difference, and a geometric one coming from the difference in travel times of the sterile neutrino through the bulk relative to the active neutrino confined to the brane. In this work we introduce a specific metric for the brane-bulk system, from which we explicitly derive extra-dimensional geodesics for the sterile neutrino, and ultimately the oscillation probability of the active-sterile two-state system. We find that for an asymmetrically-warped metric, the resonance condition involves both the neutrino energy E and the travel distance L on the brane. In other words, the resonant energy may be viewed as baseline-dependent. We show that to a good approximation, the resonance condition is not on E or on L, but rather on the product LE. The model is rich in implications, including the possibility of multiple solutions to the resonance condition, with ramifications for existing data sets, e.g., LSND and MiniBooNE. Some phenomenology with these brane-bulk resonances is discussed. |
2301.12328 | Xiao Wang | Xiao Wang, Chi Tian, and Fa Peng Huang | Model-dependent analysis method for energy budget of the cosmological
first-order phase transition | Published version in JCAP, 30 pages, 8 figures | JCAP07(2023)006 | 10.1088/1475-7516/2023/07/006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The kinetic energy of the fluid shell in the cosmological first-order phase
transition is crucial for predicting the gravitational wave signals generated
by the sound wave mechanism. We propose a model-dependent method to calculate
the kinetic energy fraction by dividing the bubble-fluid system into three
distinct regions: the symmetric phase, the broken phase, and the bubble wall.
By solving the local equation of motion of the scalar field with a
phenomenological friction term, the bubble wall velocity and the boundary
conditions of the fluid equations of both phases can be derived simultaneously.
Then, for a given particle physics model, the fluid profiles of different
hydrodynamical modes and the corresponding kinetic energy fraction can be
obtained. Our method can also capture the temperature dependency of the sound
speed of the plasma. Compared with the conventional model-independent method,
our approach is based on an accurate equation of state derived directly from
the effective potential and takes into account the contribution of the bubble
wall to the energy-momentum tensor. Therefore, our method in-principle provides
a more consistent and accurate result, which is crucial for high-precision
calculations of the gravitational waves induced by the first-order phase
transition.
| [
{
"created": "Sun, 29 Jan 2023 02:22:50 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jul 2023 08:24:09 GMT",
"version": "v2"
}
] | 2023-07-06 | [
[
"Wang",
"Xiao",
""
],
[
"Tian",
"Chi",
""
],
[
"Huang",
"Fa Peng",
""
]
] | The kinetic energy of the fluid shell in the cosmological first-order phase transition is crucial for predicting the gravitational wave signals generated by the sound wave mechanism. We propose a model-dependent method to calculate the kinetic energy fraction by dividing the bubble-fluid system into three distinct regions: the symmetric phase, the broken phase, and the bubble wall. By solving the local equation of motion of the scalar field with a phenomenological friction term, the bubble wall velocity and the boundary conditions of the fluid equations of both phases can be derived simultaneously. Then, for a given particle physics model, the fluid profiles of different hydrodynamical modes and the corresponding kinetic energy fraction can be obtained. Our method can also capture the temperature dependency of the sound speed of the plasma. Compared with the conventional model-independent method, our approach is based on an accurate equation of state derived directly from the effective potential and takes into account the contribution of the bubble wall to the energy-momentum tensor. Therefore, our method in-principle provides a more consistent and accurate result, which is crucial for high-precision calculations of the gravitational waves induced by the first-order phase transition. |
2004.12520 | Hao Sun | Tichouk, Hao Sun, and Xuan Luo | Inclusive diffractive $\rm \eta_{c}$ production in pp, pA and AA modes
at the LHC | 22figures, 24pages, submit to prd | Phys. Rev. D 101, 094006 (2020) | 10.1103/PhysRevD.101.094006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, the inclusive Pomeron-Pomeron, Reggeon-Reggeon,
Pomeron-Reggeon as well as gluon-Pomeron(-Reggeon) and photon-Pomeron(-Reggeon)
interactions for the $\rm \eta_{c}$ at the LHC energies have been examined in
proton-proton, proton-nucleus and nucleus-nucleus collision modes. The cross
section has been computed based on the NRQCD factorization and Regge theory
formalism. The cross exchange of Pomeron-Reggeon contribution is important in
$\rm pp$ and $\rm pA$ modes. The Pomeron-Pomeron contribution is significant in
$\rm AA$ mode. The Pomeron contribution is considerable for $\rm AA$ and $\rm
pA$ modes in single diffractive process where $\rm A$ undergoes the diffractive
process. Reggeon contribution is sizable in $\rm pp$ and $\rm pA$ modes where
$\rm p$ only undergoes the diffractive process. The Pomeron and Reggeon
contributions in photon-Pomeron and-Reggeon process remain smaller than that of
gluon-Pomeron and-Reggeon processes. Our results show that the experimental
study of Reggeon, Pomeron and their cross exchange can be carried out in
certain kinematic windows with the specific choice of the mode at the LHC. The
investigation can be useful to better constrain the Reggeon and Pomeron parton
content. The inclusive process serves as the background to related exclusive
processes which should be predicted.
| [
{
"created": "Mon, 27 Apr 2020 00:51:41 GMT",
"version": "v1"
}
] | 2020-05-20 | [
[
"Tichouk",
"",
""
],
[
"Sun",
"Hao",
""
],
[
"Luo",
"Xuan",
""
]
] | In this paper, the inclusive Pomeron-Pomeron, Reggeon-Reggeon, Pomeron-Reggeon as well as gluon-Pomeron(-Reggeon) and photon-Pomeron(-Reggeon) interactions for the $\rm \eta_{c}$ at the LHC energies have been examined in proton-proton, proton-nucleus and nucleus-nucleus collision modes. The cross section has been computed based on the NRQCD factorization and Regge theory formalism. The cross exchange of Pomeron-Reggeon contribution is important in $\rm pp$ and $\rm pA$ modes. The Pomeron-Pomeron contribution is significant in $\rm AA$ mode. The Pomeron contribution is considerable for $\rm AA$ and $\rm pA$ modes in single diffractive process where $\rm A$ undergoes the diffractive process. Reggeon contribution is sizable in $\rm pp$ and $\rm pA$ modes where $\rm p$ only undergoes the diffractive process. The Pomeron and Reggeon contributions in photon-Pomeron and-Reggeon process remain smaller than that of gluon-Pomeron and-Reggeon processes. Our results show that the experimental study of Reggeon, Pomeron and their cross exchange can be carried out in certain kinematic windows with the specific choice of the mode at the LHC. The investigation can be useful to better constrain the Reggeon and Pomeron parton content. The inclusive process serves as the background to related exclusive processes which should be predicted. |
2107.10560 | Angels Ramos | Albert Feijoo, Daniel Gazda, Volodymyr Magas and Angels Ramos | The ${\bar K}N$ interaction in higher partial waves | null | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | We present a chiral ${\bar K}N$ interaction model that has been developed and
optimized in order to account for the experimental data of inelastic ${\bar
K}N$ reaction channels that open at higher energies. In particular, we study
the effect of the higher partial waves which originate directly from the chiral
Lagrangian, as they could supersede the role of high-spin resonances employed
in earlier phenomenological models to describe meson-baryon cross sections in
the 2~GeV region. We present a detailed derivation of the partial wave
amplitudes that emerge from the chiral SU(3) meson-baryon Lagrangian up to the
d-waves and next-to-leading order in the chiral expansion. We implement a
nonperturbative unitarization in coupled channels and optimize the model
parameters to a large pool of experimental data in the relevant energy range
where these new contributions are expected to be important. The obtained
results are encouraging. They indicate the ability of the chiral higher partial
waves to extend the description of the scattering data to higher energies and
to account for structures in the reaction cross sections that cannot be
accommodated by theoretical models limited to the s-waves.
| [
{
"created": "Thu, 22 Jul 2021 10:24:56 GMT",
"version": "v1"
}
] | 2021-07-23 | [
[
"Feijoo",
"Albert",
""
],
[
"Gazda",
"Daniel",
""
],
[
"Magas",
"Volodymyr",
""
],
[
"Ramos",
"Angels",
""
]
] | We present a chiral ${\bar K}N$ interaction model that has been developed and optimized in order to account for the experimental data of inelastic ${\bar K}N$ reaction channels that open at higher energies. In particular, we study the effect of the higher partial waves which originate directly from the chiral Lagrangian, as they could supersede the role of high-spin resonances employed in earlier phenomenological models to describe meson-baryon cross sections in the 2~GeV region. We present a detailed derivation of the partial wave amplitudes that emerge from the chiral SU(3) meson-baryon Lagrangian up to the d-waves and next-to-leading order in the chiral expansion. We implement a nonperturbative unitarization in coupled channels and optimize the model parameters to a large pool of experimental data in the relevant energy range where these new contributions are expected to be important. The obtained results are encouraging. They indicate the ability of the chiral higher partial waves to extend the description of the scattering data to higher energies and to account for structures in the reaction cross sections that cannot be accommodated by theoretical models limited to the s-waves. |
2005.02942 | Xiao-Dong Ma | Xiao-Gang He, Xiao-Dong Ma, Jusak Tandean, German Valencia | Evading the Grossman-Nir bound with $\Delta I=3/2$ new physics | 30 pages, 5 figures, slightly expanded, typos corrected, matches
publication | JHEP 08 (2020) 034 | 10.1007/JHEP08(2020)034 | NCTS-PH/2005 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Rare kaon decays with missing energy, $K\to\pi$+$E_{\rm miss}$, have received
considerable attention because their rates can be calculated quite precisely
within the standard model (SM), where the missing energy is carried away by an
undetected neutrino-antineutrino pair. Beyond the SM, clean theoretical
predictions can also be made regarding these processes. One such prediction is
the so-called Grossman-Nir (GN) bound, which states that the branching
fractions of the $K_L$ and $K^+$ modes must satisfy the relation
$\mathcal{B}(K_L\to\pi^0$+$E_{\rm
miss})\lesssim4.3\,\mathcal{B}(K^+\to\pi^+$+$E_{\rm miss})$ and applies within
and beyond the SM, as long as the hadronic transitions change isospin by
$\Delta I=1/2$. In this paper we extend the study of these modes to include
new-physics scenarios where the missing energy is due to unobserved
lepton-number-violating neutrino pairs, invisible light new scalars, or pairs
of such scalars. The new interactions are assumed to arise above the
electroweak scale and described by an effective field theory. We explore the
possibility of violating the GN bound through $\Delta I=3/2$ contributions to
the $K\to\pi$ transitions within these scenarios and find that large violations
are only possible in the case where the missing energy is due to an invisible
light new scalar.
| [
{
"created": "Wed, 6 May 2020 16:25:10 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Aug 2020 07:05:50 GMT",
"version": "v2"
}
] | 2020-08-12 | [
[
"He",
"Xiao-Gang",
""
],
[
"Ma",
"Xiao-Dong",
""
],
[
"Tandean",
"Jusak",
""
],
[
"Valencia",
"German",
""
]
] | Rare kaon decays with missing energy, $K\to\pi$+$E_{\rm miss}$, have received considerable attention because their rates can be calculated quite precisely within the standard model (SM), where the missing energy is carried away by an undetected neutrino-antineutrino pair. Beyond the SM, clean theoretical predictions can also be made regarding these processes. One such prediction is the so-called Grossman-Nir (GN) bound, which states that the branching fractions of the $K_L$ and $K^+$ modes must satisfy the relation $\mathcal{B}(K_L\to\pi^0$+$E_{\rm miss})\lesssim4.3\,\mathcal{B}(K^+\to\pi^+$+$E_{\rm miss})$ and applies within and beyond the SM, as long as the hadronic transitions change isospin by $\Delta I=1/2$. In this paper we extend the study of these modes to include new-physics scenarios where the missing energy is due to unobserved lepton-number-violating neutrino pairs, invisible light new scalars, or pairs of such scalars. The new interactions are assumed to arise above the electroweak scale and described by an effective field theory. We explore the possibility of violating the GN bound through $\Delta I=3/2$ contributions to the $K\to\pi$ transitions within these scenarios and find that large violations are only possible in the case where the missing energy is due to an invisible light new scalar. |
1605.02807 | Vladimir Karmanov | J. Carbonell, V.A. Karmanov | Scattering solutions of Bethe-Salpeter equation in Minkowski and
Euclidean spaces | 7 pages, 2 figures, contribution to the conference Light-Cone 2015,
Frascati, Italy, 21-25 September, 2015. Submitted in Few-Body Systems | null | 10.1007/s00601-016-1105-1 | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We shortly review different methods to obtain the scattering solutions of the
Bethe-Salpeter equation in Minkowski space. We emphasize the possibility to
obtain the zero energy observables in terms of the Euclidean scattering
amplitude.
| [
{
"created": "Mon, 9 May 2016 23:53:54 GMT",
"version": "v1"
}
] | 2016-07-20 | [
[
"Carbonell",
"J.",
""
],
[
"Karmanov",
"V. A.",
""
]
] | We shortly review different methods to obtain the scattering solutions of the Bethe-Salpeter equation in Minkowski space. We emphasize the possibility to obtain the zero energy observables in terms of the Euclidean scattering amplitude. |
2011.14019 | Aliaksei Kachanovich | Aliaksei Kachanovich | Higgs decay into two leptons and a photon revisited | 6 pages, 4 figures, contribution to: ICHEP2020 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | I present new results for the Standard-Model predictions of the differential
decay rates for $H\to \ell^{+} \ell^{-} \gamma$, where $\ell=e, \mu$, and the
forward-backward asymmetries defined in terms of the flight direction of the
photon corresponding to the lepton momenta. The results dependend on the cuts
on energies and invariant masses of the final state particles. For standard
choices of these cuts the branching ratios $B(H\to e \bar e \gamma)=5.8\cdot
10^{-5}$ and $B(H\to \mu \bar \mu \gamma)=6.4\cdot 10^{-5}$ as well as the
forward-backward asymmetries $\mathcal{A}^{(e)}_{\text{FB}}=0.343$ and
$\mathcal{A}^{(\mu)}_{\text{FB}}=0.255$ have been found.
| [
{
"created": "Fri, 27 Nov 2020 22:30:52 GMT",
"version": "v1"
}
] | 2020-12-01 | [
[
"Kachanovich",
"Aliaksei",
""
]
] | I present new results for the Standard-Model predictions of the differential decay rates for $H\to \ell^{+} \ell^{-} \gamma$, where $\ell=e, \mu$, and the forward-backward asymmetries defined in terms of the flight direction of the photon corresponding to the lepton momenta. The results dependend on the cuts on energies and invariant masses of the final state particles. For standard choices of these cuts the branching ratios $B(H\to e \bar e \gamma)=5.8\cdot 10^{-5}$ and $B(H\to \mu \bar \mu \gamma)=6.4\cdot 10^{-5}$ as well as the forward-backward asymmetries $\mathcal{A}^{(e)}_{\text{FB}}=0.343$ and $\mathcal{A}^{(\mu)}_{\text{FB}}=0.255$ have been found. |
hep-ph/9609452 | null | F.A. Lunev and O.V. Pavlovsky | Singular solutions of Yang-Mills equations and bag model | minor grammatical changes; 12 pages, LaTeX | Theor.Math.Phys.117:1241-1250,1998; Teor.Mat.Fiz.117:163-174,1998 | 10.1007/BF02557164 | null | hep-ph | null | A model of quark confinement based on a singular solution of classical YM
equation is proposed. Within the framework of this model we have calculated
hadron masses that correspond to ground state configurations of quarks. Our
results are in agreement with the experiment data with accuracy 3-7 percents
for all hadronic masses except those of light pseudoscalar mesons.
| [
{
"created": "Tue, 24 Sep 1996 14:56:14 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Sep 1996 15:14:10 GMT",
"version": "v2"
},
{
"created": "Mon, 30 Sep 1996 13:09:51 GMT",
"version": "v3"
}
] | 2010-11-19 | [
[
"Lunev",
"F. A.",
""
],
[
"Pavlovsky",
"O. V.",
""
]
] | A model of quark confinement based on a singular solution of classical YM equation is proposed. Within the framework of this model we have calculated hadron masses that correspond to ground state configurations of quarks. Our results are in agreement with the experiment data with accuracy 3-7 percents for all hadronic masses except those of light pseudoscalar mesons. |
1604.01636 | Milena Soltysiak | Milena Soltysiak, Thomas Wolkanowski, and Francesco Giacosa | Large-$N_{c}$ pole trajectories of the vector kaon $K^{\ast}(892) $ and
of the scalar kaons $K_{0}^{\ast}(800)$ and $K_{0}^{\ast}(1430)$ | Presented at XI Workshop on Particle Correlations and Femtoscopy,
3-7/11/2015, Warsaw, Poland. 4 pages, 2 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the spectral functions, the poles and their trajectories for
increasing $N_{c}$ of the vector kaon state $K^{\ast}(892),$ characterized by
$I(J^{P})=\frac{1}{2}(1^{-})$, and of the scalar kaons $K_{0}^{\ast}(800)$ and
$K_{0}^{\ast}(1430),$ characterized by $I(J^{P})=\frac{1}{2}(0^{+})$. To this
end, we use relativistic QFT's Lagrangians with both derivative and
non-derivative terms. In the vector kaonic sector the spectral function is well
approximated by a Breit-Wigner function: there is one single peak and,
correspondingly, a single pole in the complex plane. On the contrary, in the
scalar sector, although the Lagrangian contains only one scalar kaonic field,
we find two poles, one corresponding to a standard quark-antiquark
,,seed\textquotedblright\ state $K_{0}^{\ast}(1430),$ and one to a
\textquotedblleft companion\textquotedblright\ dynamically generate pole
$K_{0}^{\ast}(800)$. The latter does not correspond to any peak in the scalar
kaonic spectral function, but only to an enhancement in the low-energy regime.
| [
{
"created": "Wed, 6 Apr 2016 14:18:40 GMT",
"version": "v1"
},
{
"created": "Tue, 17 May 2016 15:07:04 GMT",
"version": "v2"
}
] | 2016-05-18 | [
[
"Soltysiak",
"Milena",
""
],
[
"Wolkanowski",
"Thomas",
""
],
[
"Giacosa",
"Francesco",
""
]
] | We study the spectral functions, the poles and their trajectories for increasing $N_{c}$ of the vector kaon state $K^{\ast}(892),$ characterized by $I(J^{P})=\frac{1}{2}(1^{-})$, and of the scalar kaons $K_{0}^{\ast}(800)$ and $K_{0}^{\ast}(1430),$ characterized by $I(J^{P})=\frac{1}{2}(0^{+})$. To this end, we use relativistic QFT's Lagrangians with both derivative and non-derivative terms. In the vector kaonic sector the spectral function is well approximated by a Breit-Wigner function: there is one single peak and, correspondingly, a single pole in the complex plane. On the contrary, in the scalar sector, although the Lagrangian contains only one scalar kaonic field, we find two poles, one corresponding to a standard quark-antiquark ,,seed\textquotedblright\ state $K_{0}^{\ast}(1430),$ and one to a \textquotedblleft companion\textquotedblright\ dynamically generate pole $K_{0}^{\ast}(800)$. The latter does not correspond to any peak in the scalar kaonic spectral function, but only to an enhancement in the low-energy regime. |
0903.5200 | Zhi-Gang Wang | Zhi-Gang Wang | Analysis of the Y(4140) with QCD sum rules | 14 pages, 11 figures, 3 revision, correct two writing errors | Eur.Phys.J.C63:115-122,2009 | 10.1140/epjc/s10052-009-1097-9 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we assume that there exists a scalar $D_s^\ast {\bar
D}_s^\ast$ molecular state in the $J/\psi \phi$ invariant mass distribution,
and study its mass using the QCD sum rules. The predictions depend heavily on
the two criteria (pole dominance and convergence of the operator product
expansion) of the QCD sum rules. The value of the mass is about $M_{D_s^\ast
{\bar D}_s^\ast}=(4.43\pm0.16) \rm{GeV}$, which is inconsistent with the
experimental data. The $D_s^\ast {\bar D}_s^\ast$ is probably a virtual state
and not related to the meson Y(4140). Other possibility, such as a hybrid
charmonium is not excluded.
| [
{
"created": "Mon, 30 Mar 2009 11:54:23 GMT",
"version": "v1"
},
{
"created": "Sun, 24 May 2009 04:35:27 GMT",
"version": "v2"
},
{
"created": "Tue, 16 Jun 2009 07:37:52 GMT",
"version": "v3"
},
{
"created": "Thu, 9 Jul 2009 09:11:59 GMT",
"version": "v4"
}
] | 2009-08-29 | [
[
"Wang",
"Zhi-Gang",
""
]
] | In this article, we assume that there exists a scalar $D_s^\ast {\bar D}_s^\ast$ molecular state in the $J/\psi \phi$ invariant mass distribution, and study its mass using the QCD sum rules. The predictions depend heavily on the two criteria (pole dominance and convergence of the operator product expansion) of the QCD sum rules. The value of the mass is about $M_{D_s^\ast {\bar D}_s^\ast}=(4.43\pm0.16) \rm{GeV}$, which is inconsistent with the experimental data. The $D_s^\ast {\bar D}_s^\ast$ is probably a virtual state and not related to the meson Y(4140). Other possibility, such as a hybrid charmonium is not excluded. |
2109.05469 | Valery Nikulin V | Valery V. Nikulin and Sergey G. Rubin | Cosmological baryon/lepton asymmetry in terms of Kaluza-Klein extra
dimensions | 15 pages | International Journal of Modern Physics D (2021): 2140004 | 10.1142/S0218271821400046 | null | hep-ph gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article, we discuss the mechanism for generating the lepton/baryon
number and its subsequent conservation based on extradimensional evolution. The
internal angular momentum of extra space is related to the lepton/baryon
charge. Extra space metric are assumed to be initially asymmetric. Symmetries
appear during inflation due to an increase in entropy. Using the
multidimensional field toy model, we show that internal angular momentum can
accumulate in fermions, which could explain the lepton/baryon asymmetry of the
Universe.
| [
{
"created": "Sun, 12 Sep 2021 09:35:11 GMT",
"version": "v1"
}
] | 2021-09-14 | [
[
"Nikulin",
"Valery V.",
""
],
[
"Rubin",
"Sergey G.",
""
]
] | In this article, we discuss the mechanism for generating the lepton/baryon number and its subsequent conservation based on extradimensional evolution. The internal angular momentum of extra space is related to the lepton/baryon charge. Extra space metric are assumed to be initially asymmetric. Symmetries appear during inflation due to an increase in entropy. Using the multidimensional field toy model, we show that internal angular momentum can accumulate in fermions, which could explain the lepton/baryon asymmetry of the Universe. |
0909.4879 | Oleg Antipin A | Oleg Antipin, Kimmo Tuominen | Resizing the Conformal Window: A beta function Ansatz | Discussion on compatibility with the equivalence theorems; references
added | Phys.Rev.D81:076011,2010 | 10.1103/PhysRevD.81.076011 | null | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose an ansatz for the nonperturbative beta function of a generic
non-supersymmetric Yang-Mills theory with or without fermions in an arbitrary
representation of the gauge group. While our construction is similar to the
recently proposed Ryttov-Sannino all order beta function, the essential
difference is that it allows for the existence of an unstable ultraviolet fixed
point in addition to the predicted Bank-Zaks -like infrared stable fixed point.
Our beta function preserves all of the tested features with respect to the
non-supersymmetric Yang-Mills theories. We predict the conformal window
identifying the lower end of it as a merger of the infrared and ultraviolet
fixed points.
| [
{
"created": "Sat, 26 Sep 2009 18:06:21 GMT",
"version": "v1"
},
{
"created": "Mon, 12 Oct 2009 19:06:58 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Antipin",
"Oleg",
""
],
[
"Tuominen",
"Kimmo",
""
]
] | We propose an ansatz for the nonperturbative beta function of a generic non-supersymmetric Yang-Mills theory with or without fermions in an arbitrary representation of the gauge group. While our construction is similar to the recently proposed Ryttov-Sannino all order beta function, the essential difference is that it allows for the existence of an unstable ultraviolet fixed point in addition to the predicted Bank-Zaks -like infrared stable fixed point. Our beta function preserves all of the tested features with respect to the non-supersymmetric Yang-Mills theories. We predict the conformal window identifying the lower end of it as a merger of the infrared and ultraviolet fixed points. |
1901.02024 | Adriano Lana Cherchiglia | A. L. Cherchiglia and C. C. Nishi | Solving the strong CP problem with non-conventional CP | Comments added, comply with published version | null | 10.1007/JHEP03(2019)040 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A very simple model is presented where all CP violation in Nature is
spontaneous in origin. The CKM phase is generated unsuppressed and the strong
CP problem is solved with only moderately small couplings between the SM and
the CP violation sector or mediator sector because corrections to
$\bar{\theta}$ arise only at two loops. The latter feature follows from an
underlying unconventional CP symmetry of order 4 imposed in the sectors beyond
the SM composed of only two vector-like quarks of charge $-1/3$ and one complex
scalar singlet. No additional symmetry is necessary to implement the
Nelson-Barr mechanism.
| [
{
"created": "Mon, 7 Jan 2019 19:00:09 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Mar 2019 21:28:43 GMT",
"version": "v2"
}
] | 2019-03-29 | [
[
"Cherchiglia",
"A. L.",
""
],
[
"Nishi",
"C. C.",
""
]
] | A very simple model is presented where all CP violation in Nature is spontaneous in origin. The CKM phase is generated unsuppressed and the strong CP problem is solved with only moderately small couplings between the SM and the CP violation sector or mediator sector because corrections to $\bar{\theta}$ arise only at two loops. The latter feature follows from an underlying unconventional CP symmetry of order 4 imposed in the sectors beyond the SM composed of only two vector-like quarks of charge $-1/3$ and one complex scalar singlet. No additional symmetry is necessary to implement the Nelson-Barr mechanism. |
hep-ph/0309210 | Boris A. Gelman | Thomas D. Cohen, Boris A. Gelman, Shmuel Nussinov | New near-threshold mesons | 5 pages | Phys.Lett.B578:359-364,2004 | 10.1016/j.physletb.2003.10.065 | null | hep-ph hep-ex nucl-th | null | We show that under a number of rather plausible assumptions QCD spectrum may
contain a number of mesons which have not been predicted or observed. Such
states will have the quantum numbers of two existing mesons and masses very
close to the dissociation threshold into the two mesons. Moreover, at least one
of the two mesonic constituents itself must be very close to its dissociation
threshold. In particular, one might expect the existence of loosely bound
systems of $D$ and $\D$; similarly, $K$ and $\ff$, $\bar{K}$ and $\ff$, $K$ and
$\aa$ and $\bar{K}$ and $\aa$ can be bound. The mechanism for binding in these
cases is the S-wave kaon exchange. The nearness of one of the constituents to
its decay threshold into a kaon plus a remainder, implies that the range of the
kaon exchange force becomes abnormally long--significantly longer than $1/m_K$
which greatly aids the binding.
| [
{
"created": "Wed, 17 Sep 2003 22:35:05 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Cohen",
"Thomas D.",
""
],
[
"Gelman",
"Boris A.",
""
],
[
"Nussinov",
"Shmuel",
""
]
] | We show that under a number of rather plausible assumptions QCD spectrum may contain a number of mesons which have not been predicted or observed. Such states will have the quantum numbers of two existing mesons and masses very close to the dissociation threshold into the two mesons. Moreover, at least one of the two mesonic constituents itself must be very close to its dissociation threshold. In particular, one might expect the existence of loosely bound systems of $D$ and $\D$; similarly, $K$ and $\ff$, $\bar{K}$ and $\ff$, $K$ and $\aa$ and $\bar{K}$ and $\aa$ can be bound. The mechanism for binding in these cases is the S-wave kaon exchange. The nearness of one of the constituents to its decay threshold into a kaon plus a remainder, implies that the range of the kaon exchange force becomes abnormally long--significantly longer than $1/m_K$ which greatly aids the binding. |
2210.02707 | Mathew Thomas Dr. | Akshay A and Mathew Thomas Arun | Assisted baryon number violation from $4k+2$ dimensions | 32 pages, 2 figures, Accepted for publication in PRD | Phys. Rev. D 109, 095039 (2024) | 10.1103/PhysRevD.109.095039 | PhysRevD.109.095039 | hep-ph astro-ph.CO hep-th | http://creativecommons.org/licenses/by/4.0/ | Proton decay in six dimensions orbifolded on square $T^2/Z_2$ is highly
suppressed at tree-level. This is because baryon number violating (BNV)
operators containing only the zero mode of bulk fermions must satisfy the
selection rule $\frac{3}{2} \Delta B \pm \frac{1}{2}\Delta L = 0 \ mod \ 4$. In
this article, we show that the above relation does not prohibit mass
dimension-6 BNV operators containing Kaluza Klein (KK) partners of the bulk
fermions. Together with `spinless' adjoint scalar partner of hypercharge gauge
boson (the Dark Matter candidate), these novel operators generate Dark Matter
assisted proton decay at mass dimension-8. Here, with explicit examples of
scalar and vector baryon number violating interactions, we discuss the
importance of such $\Delta B=1 =\Delta L$ and $\Delta B=2=\Delta L$ operators
and derive the limit on New Physics.
| [
{
"created": "Thu, 6 Oct 2022 06:42:27 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Apr 2024 09:07:39 GMT",
"version": "v2"
}
] | 2024-05-28 | [
[
"A",
"Akshay",
""
],
[
"Arun",
"Mathew Thomas",
""
]
] | Proton decay in six dimensions orbifolded on square $T^2/Z_2$ is highly suppressed at tree-level. This is because baryon number violating (BNV) operators containing only the zero mode of bulk fermions must satisfy the selection rule $\frac{3}{2} \Delta B \pm \frac{1}{2}\Delta L = 0 \ mod \ 4$. In this article, we show that the above relation does not prohibit mass dimension-6 BNV operators containing Kaluza Klein (KK) partners of the bulk fermions. Together with `spinless' adjoint scalar partner of hypercharge gauge boson (the Dark Matter candidate), these novel operators generate Dark Matter assisted proton decay at mass dimension-8. Here, with explicit examples of scalar and vector baryon number violating interactions, we discuss the importance of such $\Delta B=1 =\Delta L$ and $\Delta B=2=\Delta L$ operators and derive the limit on New Physics. |
hep-ph/9705219 | Martin Savage | Jiunn-Wei Chen, Gautam Rupak and Martin J. Savage | Non-1/m_b^n Power Suppressed Contributions to Inclusive b->s l+ l-
Decays | 8 pages, 3 figures, latex | Phys.Lett.B410:285-289,1997 | 10.1016/S0370-2693(97)00956-8 | DOE/ER/41014-10-N97 | hep-ph | null | We compute non-perturbative contributions to b->s l+ l- that are not
explicitly suppressed by powers of the b-quark mass. They are proportional to
lambda_2 and arise from an interference between the free-quark amplitude and
higher order terms in the matrix element of a four-quark operator. This
correction is found to be small over most of the dalitz plot except near the
charm threshold. Unfortunately, the perturbative computation we have performed
is invalid near charm threshold and we do not except to see the structure found
at lowest order reproduced in the data. We conclude that these non-perturbative
contributions do not significantly modify the previous analysis of b->s l+ l-.
| [
{
"created": "Fri, 2 May 1997 19:53:59 GMT",
"version": "v1"
}
] | 2011-01-27 | [
[
"Chen",
"Jiunn-Wei",
""
],
[
"Rupak",
"Gautam",
""
],
[
"Savage",
"Martin J.",
""
]
] | We compute non-perturbative contributions to b->s l+ l- that are not explicitly suppressed by powers of the b-quark mass. They are proportional to lambda_2 and arise from an interference between the free-quark amplitude and higher order terms in the matrix element of a four-quark operator. This correction is found to be small over most of the dalitz plot except near the charm threshold. Unfortunately, the perturbative computation we have performed is invalid near charm threshold and we do not except to see the structure found at lowest order reproduced in the data. We conclude that these non-perturbative contributions do not significantly modify the previous analysis of b->s l+ l-. |
hep-ph/0109074 | Pelaez | J.R. Pelaez and A. Gomez Nicola (U. Complutense, Madrid) | Unitarization of the complete meson-meson scattering at one loop in
Chiral Perturbation Theory | To appear in the proceedings of QCD@work: International Workshop on
QCD: Theory and Experiment. Martina Franca (Italy) June 16-20. 2001 | AIP Conf.Proc. 602 (2001) 34-39 | 10.1063/1.1435909 | null | hep-ph | null | We report on our one-loop calculation of all the two meson scattering
amplitudes within SU(3) Chiral Perturbation Theory, i.e. with pions, kaons and
etas. Once the amplitudes are unitarized with the coupled channel Inverse
Amplitude Method, they satisfy simultaneously the correct low-energy chiral
constraints and unitarity. We obtain a remarkable description of meson-meson
scattering data up to 1.2 GeV including the scattering lengths and seven light
resonances.
| [
{
"created": "Mon, 10 Sep 2001 07:42:59 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Pelaez",
"J. R.",
"",
"U. Complutense, Madrid"
],
[
"Nicola",
"A. Gomez",
"",
"U. Complutense, Madrid"
]
] | We report on our one-loop calculation of all the two meson scattering amplitudes within SU(3) Chiral Perturbation Theory, i.e. with pions, kaons and etas. Once the amplitudes are unitarized with the coupled channel Inverse Amplitude Method, they satisfy simultaneously the correct low-energy chiral constraints and unitarity. We obtain a remarkable description of meson-meson scattering data up to 1.2 GeV including the scattering lengths and seven light resonances. |
1809.04321 | Ahmed Hammad | Luigi Delle Rose, Oliver Fischer, A. Hammad | Prospects for Heavy Scalar Searches at the LHeC | null | null | 10.1142/S0217751X19501276 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article we study the prospects of the proposed Large Hadron electron
Collider (LHeC) in the search for heavy neutral scalar particles. We consider a
minimal model with one additional complex scalar singlet that interacts with
the Standard Model (SM) via mixing with the Higgs doublet, giving rise to a
SM-like Higgs boson $h_1$ and a heavy scalar particle $h_2$. Both scalar
particles are produced via vector boson fusion and can be tested via their
decays into pairs of SM particles, analogously to the SM Higgs boson. Using
multivariate techniques we show that the LHeC is sensitive to $h_2$ with masses
between 200 and 800 GeV down to scalar mixing of $\sin^2 \alpha \sim 10^{-3}$.
| [
{
"created": "Wed, 12 Sep 2018 09:15:26 GMT",
"version": "v1"
},
{
"created": "Fri, 24 May 2019 13:39:17 GMT",
"version": "v2"
}
] | 2019-08-26 | [
[
"Rose",
"Luigi Delle",
""
],
[
"Fischer",
"Oliver",
""
],
[
"Hammad",
"A.",
""
]
] | In this article we study the prospects of the proposed Large Hadron electron Collider (LHeC) in the search for heavy neutral scalar particles. We consider a minimal model with one additional complex scalar singlet that interacts with the Standard Model (SM) via mixing with the Higgs doublet, giving rise to a SM-like Higgs boson $h_1$ and a heavy scalar particle $h_2$. Both scalar particles are produced via vector boson fusion and can be tested via their decays into pairs of SM particles, analogously to the SM Higgs boson. Using multivariate techniques we show that the LHeC is sensitive to $h_2$ with masses between 200 and 800 GeV down to scalar mixing of $\sin^2 \alpha \sim 10^{-3}$. |
1707.05605 | Paolo Cea | Paolo Cea | The $H_T$ Higgs boson at the LHC Run 2 | 14 pages, 4 figure, revised version. arXiv admin note: substantial
text overlap with arXiv:1609.09612 | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We further elaborate on the proposal that the Higgs boson should be a broad
heavy resonance, referred to as true Higgs $H_T$, with mass around $750 \,
GeV$.
We stress once again that within the Standard Model the true Higgs is the
unique possibility to implement the spontaneous symmetry breaking of the local
gauge symmetry by elementary, relativistic and strictly local scalar fields. We
discuss the most relevant decay modes of the $H_T$ boson and estimate they
partial decay widths and branching ratios. We discuss briefly the experimental
signatures of the $H_T$ Higgs boson and compare with the recent available LHC
data at $\sqrt{s} =13 \,TeV$. We find that the coupling of the $H_T$ Higgs
boson to fermions is strongly suppressed.
We also compare our theoretical expectations in the so-called golden channel
to the data collected by the ATLAS and CMS Collaborations at $\sqrt{s} =13
\,TeV$ with an integrated luminosity of $36.1 \, fb^{-1}$ and $35.9 \, fb^{-1}$
respectively. We find that our theoretical expectations are in fair good
agreement with the experimental observations. Combining the data from both the
LHC Collaborations we obtain an evidence of the heavy Higgs boson in this
channel with an estimated statistical significance of more than three standard
deviations. Finally, we argue that, if the signal is real, by the end of the
Run 2 both the LHC experiments will reach in the golden channel a statistical
significance of about five standard deviations.
| [
{
"created": "Sun, 16 Jul 2017 13:07:20 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Nov 2017 10:02:04 GMT",
"version": "v2"
}
] | 2017-11-17 | [
[
"Cea",
"Paolo",
""
]
] | We further elaborate on the proposal that the Higgs boson should be a broad heavy resonance, referred to as true Higgs $H_T$, with mass around $750 \, GeV$. We stress once again that within the Standard Model the true Higgs is the unique possibility to implement the spontaneous symmetry breaking of the local gauge symmetry by elementary, relativistic and strictly local scalar fields. We discuss the most relevant decay modes of the $H_T$ boson and estimate they partial decay widths and branching ratios. We discuss briefly the experimental signatures of the $H_T$ Higgs boson and compare with the recent available LHC data at $\sqrt{s} =13 \,TeV$. We find that the coupling of the $H_T$ Higgs boson to fermions is strongly suppressed. We also compare our theoretical expectations in the so-called golden channel to the data collected by the ATLAS and CMS Collaborations at $\sqrt{s} =13 \,TeV$ with an integrated luminosity of $36.1 \, fb^{-1}$ and $35.9 \, fb^{-1}$ respectively. We find that our theoretical expectations are in fair good agreement with the experimental observations. Combining the data from both the LHC Collaborations we obtain an evidence of the heavy Higgs boson in this channel with an estimated statistical significance of more than three standard deviations. Finally, we argue that, if the signal is real, by the end of the Run 2 both the LHC experiments will reach in the golden channel a statistical significance of about five standard deviations. |
1006.2314 | Simone Marzani | Simone Marzani | High-energy resummation at the LHC: the case of Drell-Yan processes | 5 pages, Talk given at 10th DESY Workshop on Elementary Particle
Theory: Loops and Legs 2010, Worlitz, Germany 25-30 April 2010 | Nucl.Phys.Proc.Suppl.205-206:25-30,2010 | 10.1016/j.nuclphysbps.2010.08.014 | MAN/HEP/2010/9 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We first review the general framework which enables one to resum high-energy
logarithms in hadronic processes, both in the evolution of parton densities and
in the coefficient functions. We then present an all-order calculation in
perturbative QCD of the inclusive Drell Yan and vector boson production in
hadron-hadron collisions, in the limit where centre of mass energy is much
bigger than the invariant mass of the final state. Our calculation resums
leading non-trivial logarithms in the ratio of these two scales.
We also study the phenomenological relevance of the high-energy corrections
for Drell-Yan processes at the LHC. We find that the resummation corrects the
NNLO result by a few percent, for values of the invariant mass of the lepton
pair below 100 GeV. Corrections to W, Z production are expected to be of the
same order.
| [
{
"created": "Fri, 11 Jun 2010 13:52:26 GMT",
"version": "v1"
}
] | 2010-11-26 | [
[
"Marzani",
"Simone",
""
]
] | We first review the general framework which enables one to resum high-energy logarithms in hadronic processes, both in the evolution of parton densities and in the coefficient functions. We then present an all-order calculation in perturbative QCD of the inclusive Drell Yan and vector boson production in hadron-hadron collisions, in the limit where centre of mass energy is much bigger than the invariant mass of the final state. Our calculation resums leading non-trivial logarithms in the ratio of these two scales. We also study the phenomenological relevance of the high-energy corrections for Drell-Yan processes at the LHC. We find that the resummation corrects the NNLO result by a few percent, for values of the invariant mass of the lepton pair below 100 GeV. Corrections to W, Z production are expected to be of the same order. |
2207.02498 | Ritu Garg | Ritu Garg and Alka Upadhyay | Study of F-wave bottom mesons in HQET | 12 pages, 4 figure. arXiv admin note: text overlap with
arXiv:2201.01936 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We studied $F$-wave bottom mesons in heavy quark effective theory. The
available experimental and theoretical data is used to calculate the masses of
$F$-wave bottom mesons. The decay widths of bottom mesons are analyzed to find
upper bounds of the associated couplings. We also construct Regge trajectories
for our predicted data in planes ($J$, $M^2$ ) and our results nicely fit on
Regge lines. Our results may provide a crucial information for upcoming
experimental studies.
| [
{
"created": "Wed, 6 Jul 2022 08:04:36 GMT",
"version": "v1"
}
] | 2022-07-07 | [
[
"Garg",
"Ritu",
""
],
[
"Upadhyay",
"Alka",
""
]
] | We studied $F$-wave bottom mesons in heavy quark effective theory. The available experimental and theoretical data is used to calculate the masses of $F$-wave bottom mesons. The decay widths of bottom mesons are analyzed to find upper bounds of the associated couplings. We also construct Regge trajectories for our predicted data in planes ($J$, $M^2$ ) and our results nicely fit on Regge lines. Our results may provide a crucial information for upcoming experimental studies. |
hep-ph/9502266 | Zepeda | William A. Ponce and Arnulfo Zepeda | A [SU(6)]$^4$ FLAVOR MODEL WITHOUT MIRROR FERMIONS | Z PHYS. C63, 339 (1994) | Z.Phys. C63 (1994) 339-343 | 10.1007/BF01411026 | null | hep-ph | null | We introduce a three family extension of the Pati-Salam model which is
anomaly-free and contains in a single irreducible representation the known
quarks and leptons without mirror fermions. Assuming that the breaking of the
symmetry admits the implementation of the survival hypothesis, we calculate the
mass scales using the renormalization group equation. Finally we show that the
proton remains perturbatively stable.
| [
{
"created": "Thu, 9 Feb 1995 20:23:09 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Ponce",
"William A.",
""
],
[
"Zepeda",
"Arnulfo",
""
]
] | We introduce a three family extension of the Pati-Salam model which is anomaly-free and contains in a single irreducible representation the known quarks and leptons without mirror fermions. Assuming that the breaking of the symmetry admits the implementation of the survival hypothesis, we calculate the mass scales using the renormalization group equation. Finally we show that the proton remains perturbatively stable. |
hep-ph/9601367 | Thomas | Savas Dimopoulos, Michael Dine, Stuart Raby, Scott Thomas | Experimental Signatures of Low Energy Gauge Mediated Supersymmetry
Breaking | 11 pages, requires phyzzx, published version | Phys.Rev.Lett. 76 (1996) 3494-3497 | 10.1103/PhysRevLett.76.3494 | SLAC-PUB-96-7104 | hep-ph | null | The experimental signatures for gauge mediated supersymmetry breaking are
presented. The phenomenology associated with this class of models is
distinctive since the gravitino is naturally the LSP. The next lightest
supersymmetric particle (NLSP) can be a gaugino, Higgsino, or right handed
slepton. Decay of the NLSP to its partner plus the LSP proceeds through the
Goldstino component of the gravitino. For a significant range of parameters
this decay can take place within the detector, and can be measured as a
displaced vertex or kink in a charged particle track. In the case that the NLSP
is mostly gaugino, we identify the discovery modes as $e^+e^- \rightarrow
\gamma \gamma + \Emiss$, and $p \bar{p} \rightarrow l^+ l^- \gamma \gamma +
\EmissT$. If the NLSP is a right handed slepton the discovery modes are $e^+
e^- \rightarrow l^+ l^- + \Emiss$ and $p \bar{p} \rightarrow l^+ l^- +
\EmissT$. An NLSP which is mostly Higgsino is also considered. Finally, these
theories can contain scalar particles which mediate sub-millimeter range
coherent forces of gravitational strength.
| [
{
"created": "Tue, 30 Jan 1996 07:04:28 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Feb 1996 05:04:08 GMT",
"version": "v2"
},
{
"created": "Tue, 2 Jul 1996 04:47:57 GMT",
"version": "v3"
}
] | 2009-10-28 | [
[
"Dimopoulos",
"Savas",
""
],
[
"Dine",
"Michael",
""
],
[
"Raby",
"Stuart",
""
],
[
"Thomas",
"Scott",
""
]
] | The experimental signatures for gauge mediated supersymmetry breaking are presented. The phenomenology associated with this class of models is distinctive since the gravitino is naturally the LSP. The next lightest supersymmetric particle (NLSP) can be a gaugino, Higgsino, or right handed slepton. Decay of the NLSP to its partner plus the LSP proceeds through the Goldstino component of the gravitino. For a significant range of parameters this decay can take place within the detector, and can be measured as a displaced vertex or kink in a charged particle track. In the case that the NLSP is mostly gaugino, we identify the discovery modes as $e^+e^- \rightarrow \gamma \gamma + \Emiss$, and $p \bar{p} \rightarrow l^+ l^- \gamma \gamma + \EmissT$. If the NLSP is a right handed slepton the discovery modes are $e^+ e^- \rightarrow l^+ l^- + \Emiss$ and $p \bar{p} \rightarrow l^+ l^- + \EmissT$. An NLSP which is mostly Higgsino is also considered. Finally, these theories can contain scalar particles which mediate sub-millimeter range coherent forces of gravitational strength. |
1107.0738 | Wei Chao | Wei Chao and Ya-juan Zheng | Relatively Large Theta13 from Modification to the Tri-bimaximal,
Bimaximal and Democratic Neutrino Mixing Matrices | 18 pages, 17 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inspired by the recent T2K indication of a relatively large theta_{13}, we
provide a systematic study of some general modifications to three mostly
discussed neutrino mixing patterns, i.e., tri-bimaximal, bimaximal and
democratic mixing matrices. The correlation between theta_{13} and two large
mixing angles are provided according to each modifications. The
phenomenological predictions of theta_{12} and theta_{23} are also discussed.
After the exclusion of several minimal modifications, we still have reasonable
predictions of three mixing angles in 3 Sigma level for other scenarios.
| [
{
"created": "Mon, 4 Jul 2011 20:30:29 GMT",
"version": "v1"
}
] | 2011-07-06 | [
[
"Chao",
"Wei",
""
],
[
"Zheng",
"Ya-juan",
""
]
] | Inspired by the recent T2K indication of a relatively large theta_{13}, we provide a systematic study of some general modifications to three mostly discussed neutrino mixing patterns, i.e., tri-bimaximal, bimaximal and democratic mixing matrices. The correlation between theta_{13} and two large mixing angles are provided according to each modifications. The phenomenological predictions of theta_{12} and theta_{23} are also discussed. After the exclusion of several minimal modifications, we still have reasonable predictions of three mixing angles in 3 Sigma level for other scenarios. |
1706.04529 | Masahiro Ibe | Rupert Coy, Michele Frigerio, Masahiro Ibe | Dynamical Clockwork Axions | 41 pages | null | 10.1007/JHEP10(2017)002 | IPMU17-0087 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The clockwork mechanism is a novel method for generating a large separation
between the dynamical scale and interaction scale of a theory. We demonstrate
how the mechanism can arise from a sequence of strongly-coupled sectors. This
framework avoids elementary scalar fields as well as ad hoc continuous global
symmetries, both of which are subject to serious stability issues. The
clockwork factor, $q$, is determined by the consistency of the strong dynamics.
The preserved global $U(1)$ of the clockwork appears as an accidental symmetry,
resulting from discrete or $U(1)$ gauge symmetries, and it is spontaneously
broken by the chiral condensates. We apply such a dynamical clockwork to
construct models with an effectively invisible QCD axion from TeV-scale strong
dynamics. The axion couplings are determined by the localisation of the
Standard Model interactions along the clockwork sequence. The TeV spectrum
includes either coloured hadrons or vector-like quarks. Dark matter can be
accounted for by the axion or the lightest neutral baryons, which are
accidentally stable.
| [
{
"created": "Wed, 14 Jun 2017 15:06:25 GMT",
"version": "v1"
}
] | 2017-10-25 | [
[
"Coy",
"Rupert",
""
],
[
"Frigerio",
"Michele",
""
],
[
"Ibe",
"Masahiro",
""
]
] | The clockwork mechanism is a novel method for generating a large separation between the dynamical scale and interaction scale of a theory. We demonstrate how the mechanism can arise from a sequence of strongly-coupled sectors. This framework avoids elementary scalar fields as well as ad hoc continuous global symmetries, both of which are subject to serious stability issues. The clockwork factor, $q$, is determined by the consistency of the strong dynamics. The preserved global $U(1)$ of the clockwork appears as an accidental symmetry, resulting from discrete or $U(1)$ gauge symmetries, and it is spontaneously broken by the chiral condensates. We apply such a dynamical clockwork to construct models with an effectively invisible QCD axion from TeV-scale strong dynamics. The axion couplings are determined by the localisation of the Standard Model interactions along the clockwork sequence. The TeV spectrum includes either coloured hadrons or vector-like quarks. Dark matter can be accounted for by the axion or the lightest neutral baryons, which are accidentally stable. |
2308.09120 | Victor Goncalves | Celsina N. Azevedo, Victor P. Goncalves, Bruno D. Moreira | Associated vector meson and bound-free electron-positron pair
photoproduction in ultraperipheral $PbPb$ collisions | 5 pages, 2 figures, 1 table. arXiv admin note: substantial text
overlap with arXiv:2306.05519 | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this letter we analyze the associated production of a vector meson with
the bound - free $e^+e^-$ process in ultraperipheral $PbPb$ collisions through
the double scattering mechanism for the energy of the Large Hadron Collider
(LHC). Such process is characterized by the presence of a meson and a positron
in the final state and by a forward hydrogen - like ion with a distinct
electric charge. We present our predictions for the total cross sections and
rapidity distributions considering the rapidity ranges covered by the ALICE and
LHCb detectors, which indicate that a future experimental analysis of the $\phi
+ e^+$ and $J/\Psi + e^+$ final states is feasible.
| [
{
"created": "Thu, 17 Aug 2023 17:56:14 GMT",
"version": "v1"
}
] | 2023-08-21 | [
[
"Azevedo",
"Celsina N.",
""
],
[
"Goncalves",
"Victor P.",
""
],
[
"Moreira",
"Bruno D.",
""
]
] | In this letter we analyze the associated production of a vector meson with the bound - free $e^+e^-$ process in ultraperipheral $PbPb$ collisions through the double scattering mechanism for the energy of the Large Hadron Collider (LHC). Such process is characterized by the presence of a meson and a positron in the final state and by a forward hydrogen - like ion with a distinct electric charge. We present our predictions for the total cross sections and rapidity distributions considering the rapidity ranges covered by the ALICE and LHCb detectors, which indicate that a future experimental analysis of the $\phi + e^+$ and $J/\Psi + e^+$ final states is feasible. |
hep-ph/0104156 | Pyungwon Ko | P. Ko (KAIST) | SUSY CP violations in K and B systems | To appear in the proceeding of CICHEP 2001 | null | 10.1142/9789812777379_0026 | KAIST-TH 2001/09 | hep-ph | null | I report our recent works on the effects of % flavor conserving CP violating
phases in SUSY models on B and K phenomenology.
| [
{
"created": "Tue, 17 Apr 2001 04:22:08 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Ko",
"P.",
"",
"KAIST"
]
] | I report our recent works on the effects of % flavor conserving CP violating phases in SUSY models on B and K phenomenology. |
1701.07866 | Thomas A. Trainor | Thomas A. Trainor | Manifestations of minimum-bias dijets in high-energy nuclear collisions | 25 pages, 28 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dijets observed near midrapidity in high-energy nuclear collisions result
from large-angle scattering of low-$x$ partons (gluons) within projectile
hadrons as a signature manifestation of QCD. Within the same collisions it has
been claimed that hydrodynamic flows (radial, elliptic and "higher harmonic"
flows) carried by a dense QCD medium or quark-gluon plasma (QGP) dominate the
observed hadronic final state. The flow-QGP narrative is imposed {\em a priori}
on primary particle data, and of all possible analysis methods a subset A that
seems to support that narrative is preferred. The present study explores an
alternative minimum-bias (MB) jet narrative -- quantitative correspondence of
MB dijet manifestations in the hadronic final state with measured {\em isolated
jet} properties. The latter incorporates a different set of methods B that
emerge from inductive study of primary particle data without {\em a priori}
assumptions. The resulting system of methods and data manifestations is
represented by a two-component (soft + hard) model (TCM) of hadron production.
A survey of methods reveals that type A tends to discard substantial
information carried by primary particle data whereas type B retains almost all
information in both primary particle data from nuclear collisions and from
isolated jets. The main goal of the present study is a review of MB dijet
contributions to high-energy collisions in small and large systems relative to
measured isolated-jet properties. Representative analysis methods from types A
and B are compared in the context of MB jet manifestations. This study suggests
that at least some data features commonly attributed to flows actually result
from MB dijets and thereby challenges the flow-QGP narrative.
| [
{
"created": "Thu, 26 Jan 2017 20:17:46 GMT",
"version": "v1"
}
] | 2017-01-30 | [
[
"Trainor",
"Thomas A.",
""
]
] | Dijets observed near midrapidity in high-energy nuclear collisions result from large-angle scattering of low-$x$ partons (gluons) within projectile hadrons as a signature manifestation of QCD. Within the same collisions it has been claimed that hydrodynamic flows (radial, elliptic and "higher harmonic" flows) carried by a dense QCD medium or quark-gluon plasma (QGP) dominate the observed hadronic final state. The flow-QGP narrative is imposed {\em a priori} on primary particle data, and of all possible analysis methods a subset A that seems to support that narrative is preferred. The present study explores an alternative minimum-bias (MB) jet narrative -- quantitative correspondence of MB dijet manifestations in the hadronic final state with measured {\em isolated jet} properties. The latter incorporates a different set of methods B that emerge from inductive study of primary particle data without {\em a priori} assumptions. The resulting system of methods and data manifestations is represented by a two-component (soft + hard) model (TCM) of hadron production. A survey of methods reveals that type A tends to discard substantial information carried by primary particle data whereas type B retains almost all information in both primary particle data from nuclear collisions and from isolated jets. The main goal of the present study is a review of MB dijet contributions to high-energy collisions in small and large systems relative to measured isolated-jet properties. Representative analysis methods from types A and B are compared in the context of MB jet manifestations. This study suggests that at least some data features commonly attributed to flows actually result from MB dijets and thereby challenges the flow-QGP narrative. |
1405.2138 | Chaehyun Yu | P. Ko (KIAS), Yuji Omura (Nagoya University), Chaehyun Yu (KIAS) | Dark Matter and Dark Force in the Type-I Inert 2HDM with Local U(1)_H
Gauge Symmetry | 24 pages, 6 figures, version published in JHEP | JHEP 1411, 054 (2014) | 10.1007/JHEP11(2014)054 | KIAS-PREPRINT-P14030 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss dark matter (DM) physics in the Type-I inert two-Higgs-doublet
model (2HDM) with local U(1)_H Higgs gauge symmetry. The local U(1)_H gauge
symmetry is assigned to the extra Higgs doublet in order to avoid the
Higgs-mediated flavor problems, and it spontaneously breaks down to its
discrete subgroup. The lightest neutral scalar component H of the
U(1)_H-charged Higgs doublet, which does not have Yukawa couplings with the
Standard-Model (SM) fermions, is stable because of the remnant discrete
symmetry, and it interacts with the SM particles through the U(1)_H gauge boson
(Z_H) exchange as well as the SM boson exchange. We first investigate the
constraint on the U(1)_H gauge interaction, especially through the kinetic and
mass mixing between the SM gauge bosons and the extra gauge boson. Then we
discuss dark matter physics in our 2HDM: thermal relic density, and
direct/indirect detections of dark matter. The additional U(1)_H gauge
interaction plays a crucial role in reducing the DM thermal relic density. The
most important result within the inert DM model with local U(1)_H symmetry is
that ~ O(10) GeV dark matter scenario, which is strongly disfavored in the
usual Inert Doublet Model (IDM) with Z_2 symmetry, is revived in our model
because of newly open channels, H H -> Z_H Z_H , Z_H Z. Exotic Higgs decays, h
-> Z_H Z_H, Z Z_H, would be distinctive signatures of the inert 2HDM with local
U(1)_H symmetry.
| [
{
"created": "Fri, 9 May 2014 04:34:07 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Nov 2014 08:57:27 GMT",
"version": "v2"
}
] | 2015-06-19 | [
[
"Ko",
"P.",
"",
"KIAS"
],
[
"Omura",
"Yuji",
"",
"Nagoya University"
],
[
"Yu",
"Chaehyun",
"",
"KIAS"
]
] | We discuss dark matter (DM) physics in the Type-I inert two-Higgs-doublet model (2HDM) with local U(1)_H Higgs gauge symmetry. The local U(1)_H gauge symmetry is assigned to the extra Higgs doublet in order to avoid the Higgs-mediated flavor problems, and it spontaneously breaks down to its discrete subgroup. The lightest neutral scalar component H of the U(1)_H-charged Higgs doublet, which does not have Yukawa couplings with the Standard-Model (SM) fermions, is stable because of the remnant discrete symmetry, and it interacts with the SM particles through the U(1)_H gauge boson (Z_H) exchange as well as the SM boson exchange. We first investigate the constraint on the U(1)_H gauge interaction, especially through the kinetic and mass mixing between the SM gauge bosons and the extra gauge boson. Then we discuss dark matter physics in our 2HDM: thermal relic density, and direct/indirect detections of dark matter. The additional U(1)_H gauge interaction plays a crucial role in reducing the DM thermal relic density. The most important result within the inert DM model with local U(1)_H symmetry is that ~ O(10) GeV dark matter scenario, which is strongly disfavored in the usual Inert Doublet Model (IDM) with Z_2 symmetry, is revived in our model because of newly open channels, H H -> Z_H Z_H , Z_H Z. Exotic Higgs decays, h -> Z_H Z_H, Z Z_H, would be distinctive signatures of the inert 2HDM with local U(1)_H symmetry. |
hep-ph/9712215 | Omar Miranda | O. G. Miranda, V. Semikoz, Jose W. F. Valle (U. de Valencia,
IFIC-CSIC) | Neutrino Electron Scattering and Electroweak Gauge Structure: Future
Tests | 22 pages, revtex, 4 figures included, accepted for publication in
Phys. Rev. D | Phys.Rev.D58:013007,1998 | 10.1103/PhysRevD.58.013007 | null | hep-ph astro-ph | null | Low-energy high-resolution neutrino-electron scattering experiments may play
an important role in testing the gauge structure of the electroweak
interaction. We propose the use of radioactive neutrino sources (e.g.
$^{51}$Cr) in underground experiments such as BOREXINO, HELLAZ and LAMA. As an
illustration, we display the sensitivity of these detectors in testing the
possible existence of extra neutral gauge bosons, both in the framework of E_6
models and of models with left-right symmetry.
| [
{
"created": "Mon, 1 Dec 1997 14:44:39 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Dec 1997 20:58:58 GMT",
"version": "v2"
},
{
"created": "Wed, 3 Dec 1997 13:57:10 GMT",
"version": "v3"
},
{
"created": "Thu, 30 Apr 1998 14:32:03 GMT",
"version": "v4"
}
] | 2009-09-17 | [
[
"Miranda",
"O. G.",
"",
"U. de Valencia,\n IFIC-CSIC"
],
[
"Semikoz",
"V.",
"",
"U. de Valencia,\n IFIC-CSIC"
],
[
"Valle",
"Jose W. F.",
"",
"U. de Valencia,\n IFIC-CSIC"
]
] | Low-energy high-resolution neutrino-electron scattering experiments may play an important role in testing the gauge structure of the electroweak interaction. We propose the use of radioactive neutrino sources (e.g. $^{51}$Cr) in underground experiments such as BOREXINO, HELLAZ and LAMA. As an illustration, we display the sensitivity of these detectors in testing the possible existence of extra neutral gauge bosons, both in the framework of E_6 models and of models with left-right symmetry. |
1202.0080 | Lei Guo | Guo Lei, Zhang Ren-You, Ma Wen-Gan, and Han Liang | QCD corrections to the $\gamma\gamma b\bar b$ production at the ILC | 16 pages, 5 figures | Physics Letters B 708 (2012) 138-143 | 10.1016/j.physletb.2012.01.044 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The $e^+e^- \to \gamma\gamma b\bar b$ is an irreducible background process in
measuring the $H^0 \to \gamma\gamma$ decay width, if Higgs boson is produced in
association with a $Z^0$-boson which subsequently decays via $Z^0 \to b\bar b$
at the ILC. In this paper we study the impact of the ${\cal O}(\alpha_s)$ QCD
corrections to the observables of the $e^+e^- \to \gamma\gamma b\bar b$ process
in the standard model. We investigate the dependence of the leading-order and
${\cal O}(\alpha_s)$ QCD corrected cross sections on colliding energy and the
additional jet veto schemes. We also present the results of the LO and ${\cal
O}(\alpha_s)$ QCD corrected distributions of the transverse momenta of final
particles, and the invariant masses of $b\bar b$- and $\gamma\gamma$-pair.
| [
{
"created": "Wed, 1 Feb 2012 02:06:31 GMT",
"version": "v1"
}
] | 2012-02-02 | [
[
"Lei",
"Guo",
""
],
[
"Ren-You",
"Zhang",
""
],
[
"Wen-Gan",
"Ma",
""
],
[
"Liang",
"Han",
""
]
] | The $e^+e^- \to \gamma\gamma b\bar b$ is an irreducible background process in measuring the $H^0 \to \gamma\gamma$ decay width, if Higgs boson is produced in association with a $Z^0$-boson which subsequently decays via $Z^0 \to b\bar b$ at the ILC. In this paper we study the impact of the ${\cal O}(\alpha_s)$ QCD corrections to the observables of the $e^+e^- \to \gamma\gamma b\bar b$ process in the standard model. We investigate the dependence of the leading-order and ${\cal O}(\alpha_s)$ QCD corrected cross sections on colliding energy and the additional jet veto schemes. We also present the results of the LO and ${\cal O}(\alpha_s)$ QCD corrected distributions of the transverse momenta of final particles, and the invariant masses of $b\bar b$- and $\gamma\gamma$-pair. |
hep-ph/0001182 | Ram Brustein | Ram Brustein, Merav Hadad | Production of fermions in models of string cosmology | 12 pages, no figures, additional clarifications and typos corrected | Phys.Lett. B477 (2000) 263-268 | 10.1016/S0370-2693(00)00175-1 | TAUP-2610-2000 | hep-ph gr-qc hep-th | null | Production of spin 1/2 fermions and gravitinos by the standard mechanism of
amplification of quantum fluctuations during the dilaton-driven inflation phase
in models of string cosmology is highly suppressed. Constraints on string
cosmology models from gravitational production of gravitinos, contrary to
expectations, are similar to constraints on other models.
| [
{
"created": "Tue, 18 Jan 2000 13:51:47 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Feb 2000 08:41:15 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Brustein",
"Ram",
""
],
[
"Hadad",
"Merav",
""
]
] | Production of spin 1/2 fermions and gravitinos by the standard mechanism of amplification of quantum fluctuations during the dilaton-driven inflation phase in models of string cosmology is highly suppressed. Constraints on string cosmology models from gravitational production of gravitinos, contrary to expectations, are similar to constraints on other models. |
hep-ph/9504374 | Arthur Hebecker | W. Buchmuller, A. Hebecker | A PARTON MODEL FOR DIFFRACTIVE PROCESSES IN DEEP INELASTIC SCATTERING | 8 pages LaTex, 3 figures appended as uuencoded ps-files, complete
ps-file of the paper available via anonymous ftp at
ftp://x4u2.desy.de/pub/preprints/desy/1995/desy95-077.ps | Phys.Lett.B355:573-578,1995 | 10.1016/0370-2693(95)00721-V | DESY 95-077 | hep-ph | null | We demonstrate that the global properties of the ``rapidity gap'' events,
observed at HERA, can be understood based on electron-gluon scattering as the
underlying partonic process. Using the measured inclusive structure function
$F_2$ to determine the parameters of the parton model, the diffractive
structure function $F_2^D$ is predicted. The ratio of diffractive and inclusive
cross sections, $R_D = \sigma_D/\sigma_{incl}\simeq 1/9$, is determined by the
probability of the produced quark-antiquark pair to evolve into a colour
singlet state. This colour singlet cluster may fragment into hadrons
independently of the proton remnant, yielding the observed gap in rapidity.
| [
{
"created": "Mon, 24 Apr 1995 12:45:46 GMT",
"version": "v1"
}
] | 2009-02-20 | [
[
"Buchmuller",
"W.",
""
],
[
"Hebecker",
"A.",
""
]
] | We demonstrate that the global properties of the ``rapidity gap'' events, observed at HERA, can be understood based on electron-gluon scattering as the underlying partonic process. Using the measured inclusive structure function $F_2$ to determine the parameters of the parton model, the diffractive structure function $F_2^D$ is predicted. The ratio of diffractive and inclusive cross sections, $R_D = \sigma_D/\sigma_{incl}\simeq 1/9$, is determined by the probability of the produced quark-antiquark pair to evolve into a colour singlet state. This colour singlet cluster may fragment into hadrons independently of the proton remnant, yielding the observed gap in rapidity. |
hep-ph/0112192 | Zhongzhi Song | Zhongzhi Song (PKU) and Kuang-Ta Chao | Diffractive D_s production in charged current DIS | 6 pages, 5 eps figures, final version to appear in PLB | Phys.Lett. B529 (2002) 77 | 10.1016/S0370-2693(02)01229-7 | PKU-TP-2001-72 | hep-ph | null | We present a perturbative QCD calculation of diffractive $D_s$ production in
charged current deep inelastic scattering. In the two-gluon exchange model, we
analyze the diffractive process $\nu N \to \mu^- N \Ds$, which may provide
useful information for the gluon structure of nucleons and the diffraction
mechanism in QCD. The cross section of diffractive $D_s$ production with
$\xBj=0.005$-0.05 and $E_\nu=50$ Gev is found to be $2.7\times10^{-5}$ pb. In
spite of this small cross section, the high luminosity available at the
$\nu$-Factory in the future would lead to a sizable number of diffraction
events.
| [
{
"created": "Fri, 14 Dec 2001 01:35:40 GMT",
"version": "v1"
},
{
"created": "Sun, 3 Feb 2002 14:41:27 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Song",
"Zhongzhi",
"",
"PKU"
],
[
"Chao",
"Kuang-Ta",
""
]
] | We present a perturbative QCD calculation of diffractive $D_s$ production in charged current deep inelastic scattering. In the two-gluon exchange model, we analyze the diffractive process $\nu N \to \mu^- N \Ds$, which may provide useful information for the gluon structure of nucleons and the diffraction mechanism in QCD. The cross section of diffractive $D_s$ production with $\xBj=0.005$-0.05 and $E_\nu=50$ Gev is found to be $2.7\times10^{-5}$ pb. In spite of this small cross section, the high luminosity available at the $\nu$-Factory in the future would lead to a sizable number of diffraction events. |
hep-ph/0412351 | Mike Berger | M. S. Berger | Lorentz Violation in Supersymmetric Field Theories | 6 pages, Presented at the 3rd Meeting on CPT and Lorentz Symmetry
(CPT 04), Bloomington, Indiana, 4-7 Aug 2004 | null | 10.1142/9789812702173_0036 | IUHET-480 | hep-ph | null | Broken spacetime symmetries might emerge from a fundamental physical theory.
The effective low-energy theory might be expected to exhibit violations of
supersymmetry and Lorentz invariance. Some illustrative models which combine
supersymmetry and Lorentz violation are described, and a superspace formulation
is given.
| [
{
"created": "Wed, 22 Dec 2004 20:11:12 GMT",
"version": "v1"
}
] | 2016-11-03 | [
[
"Berger",
"M. S.",
""
]
] | Broken spacetime symmetries might emerge from a fundamental physical theory. The effective low-energy theory might be expected to exhibit violations of supersymmetry and Lorentz invariance. Some illustrative models which combine supersymmetry and Lorentz violation are described, and a superspace formulation is given. |
0706.4179 | Benjamin Grinstein | Benjamin Grinstein | Overview: Sides of the Unitarity Triangle | Talk presented at 4th International Workshop on the CKM Unitarity
Triangle, December 12-16, 2006, Nagoya, Japan; latex, 6 pp | null | null | UCSD-PTH-07-06 | hep-ph | null | This is an opening talk for the workshop and is intended to be provocative.
We take a stab at the following questions: How well do we really know the sides
of the unitarity triangle? What else could we do to improve? (I propose several
new measurements). What precision should we ultimately aim at in the
determination of CKM elements? What have we learned so far about flavor
physics? Where do we go from here?
| [
{
"created": "Thu, 28 Jun 2007 10:12:54 GMT",
"version": "v1"
}
] | 2007-06-29 | [
[
"Grinstein",
"Benjamin",
""
]
] | This is an opening talk for the workshop and is intended to be provocative. We take a stab at the following questions: How well do we really know the sides of the unitarity triangle? What else could we do to improve? (I propose several new measurements). What precision should we ultimately aim at in the determination of CKM elements? What have we learned so far about flavor physics? Where do we go from here? |
1503.04196 | Cem Salih Un | Qaisar Shafi, Sukru Hanif Tanyildizi, Cem Salih Un | Neutralino Dark Matter and Other LHC Predictions from Quasi Yukawa
Unification | null | null | 10.1016/j.nuclphysb.2015.09.019 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the dark matter and LHC implications of t-b-tau quasi Yukawa
unification in the framework of supersymmetric models based on the gauge
symmetry G=SU(4)_{c}\times SU(2)_{L}\times SU(2)_{R}. The deviation from exact
Yukawa unification is quantified by a dimensionless parameter C (|C| <~ 0.2),
such that the Yukawa couplings at M_GUT are related by y_t:y_b:y_tau=|1+C| :
|1-C| : |1+3C|. In contrast to earlier studies which focused on universal
gaugino masses, we consider non-universal gaugino masses at M_GUT that are
compatible with the gauge symmetry G. We perform two independent scans of the
fundamental parameter space, one of which employs ISAJET, while the other uses
SoftSusy interfaced with SuperIso. These scans reveal qualitatively similar
allowed regions in the parameter space, and yield a variety of neutralino dark
matter scenarios consistent with the observations. These include stau and
chargino coannihilation scenarios, the A-resonance scenario, as well as
Higgsino dark matter solution which is more readily probed by direct detection
searches. The gluino mass is found to be <~ 4.2 TeV, the stop mass is >~ 2 TeV,
while the first two family squarks and sleptons are of order 4-5 TeV and 3 TeV
respectively.
| [
{
"created": "Fri, 13 Mar 2015 19:59:16 GMT",
"version": "v1"
}
] | 2015-12-09 | [
[
"Shafi",
"Qaisar",
""
],
[
"Tanyildizi",
"Sukru Hanif",
""
],
[
"Un",
"Cem Salih",
""
]
] | We explore the dark matter and LHC implications of t-b-tau quasi Yukawa unification in the framework of supersymmetric models based on the gauge symmetry G=SU(4)_{c}\times SU(2)_{L}\times SU(2)_{R}. The deviation from exact Yukawa unification is quantified by a dimensionless parameter C (|C| <~ 0.2), such that the Yukawa couplings at M_GUT are related by y_t:y_b:y_tau=|1+C| : |1-C| : |1+3C|. In contrast to earlier studies which focused on universal gaugino masses, we consider non-universal gaugino masses at M_GUT that are compatible with the gauge symmetry G. We perform two independent scans of the fundamental parameter space, one of which employs ISAJET, while the other uses SoftSusy interfaced with SuperIso. These scans reveal qualitatively similar allowed regions in the parameter space, and yield a variety of neutralino dark matter scenarios consistent with the observations. These include stau and chargino coannihilation scenarios, the A-resonance scenario, as well as Higgsino dark matter solution which is more readily probed by direct detection searches. The gluino mass is found to be <~ 4.2 TeV, the stop mass is >~ 2 TeV, while the first two family squarks and sleptons are of order 4-5 TeV and 3 TeV respectively. |
hep-ph/0211300 | Patrick Huber | P. Huber, M. Lindner and W. Winter | Synergies between the first-generation JHF-SK and NuMI superbeam
experiments | 29 pages, 10 figures | Nucl.Phys. B654 (2003) 3-29 | 10.1016/S0550-3213(03)00063-4 | null | hep-ph hep-ex | null | We discuss synergies in the combination of the first-generation JHF to
Super-Kamiokande and NuMI off-axis superbeam experiments. With synergies we
mean effects which go beyond simply adding the statistics of the two
experiments. As a first important result, we do not observe interesting synergy
effects in the combination of the two experiments as they are planned right
now. However, we find that with minor modifications, such as a different NuMI
baseline or a partial antineutrino running, one could do much richer physics
with both experiments combined. Specifically, we demonstrate that one could,
depending on the value of the solar mass squared difference, either measure the
sign of the atmospheric mass squared difference or CP violation already with
the initial stage experiments. Our main results are presented in a way that can
be easily interpreted in terms of the forthcoming KamLAND result.
| [
{
"created": "Tue, 19 Nov 2002 13:24:29 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Huber",
"P.",
""
],
[
"Lindner",
"M.",
""
],
[
"Winter",
"W.",
""
]
] | We discuss synergies in the combination of the first-generation JHF to Super-Kamiokande and NuMI off-axis superbeam experiments. With synergies we mean effects which go beyond simply adding the statistics of the two experiments. As a first important result, we do not observe interesting synergy effects in the combination of the two experiments as they are planned right now. However, we find that with minor modifications, such as a different NuMI baseline or a partial antineutrino running, one could do much richer physics with both experiments combined. Specifically, we demonstrate that one could, depending on the value of the solar mass squared difference, either measure the sign of the atmospheric mass squared difference or CP violation already with the initial stage experiments. Our main results are presented in a way that can be easily interpreted in terms of the forthcoming KamLAND result. |
hep-ph/9503347 | Adrian Dumitru | A. Dumitru, U. Katscher, J.A. Maruhn, H. St\"ocker, W. Greiner, D.H.
Rischke | Thermal photons as a measure for the rapidity dependence of the
temperature | 3 Figures | Z.Phys. A353 (1995) 187-190 | 10.1007/BF01295896 | UFTP-381/1995 | hep-ph | null | The rapidity distribution of thermal photons produced in Pb+Pb collisions at
CERN-SPS energies is calculated within scaling and three-fluid hydrodynamics.
It is shown that these scenarios lead to very different rapidity spectra. A
measurement of the rapidity dependence of photon radiation can give cleaner
insight into the reaction dynamics than pion spectra, especially into the
rapidity dependence of the temperature.
| [
{
"created": "Thu, 16 Mar 1995 09:06:27 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Dumitru",
"A.",
""
],
[
"Katscher",
"U.",
""
],
[
"Maruhn",
"J. A.",
""
],
[
"Stöcker",
"H.",
""
],
[
"Greiner",
"W.",
""
],
[
"Rischke",
"D. H.",
""
]
] | The rapidity distribution of thermal photons produced in Pb+Pb collisions at CERN-SPS energies is calculated within scaling and three-fluid hydrodynamics. It is shown that these scenarios lead to very different rapidity spectra. A measurement of the rapidity dependence of photon radiation can give cleaner insight into the reaction dynamics than pion spectra, especially into the rapidity dependence of the temperature. |
hep-ph/0008240 | W. F. Kao | W. F. Kao, Guey-Lin Lin and Jie-Jun Tseng | A new look at the pair-production width in a strong magnetic field | 8 pages, 2 figures, Revtex, Some comments added | Phys.Lett. B495 (2000) 105-113 | 10.1016/S0370-2693(00)01220-X | NCTU-HEP-0003 | hep-ph hep-th | null | We reexamine the process $\gamma\to e^++ e^-$ in a background magnetic field
comparable to $B_c\equiv m_e^2/e$. This process is known to be non-perturbative
in the magnetic-field strength. However, it can be shown that the {\it moments}
of the above pair production width is proportional to the derivatives of photon
polarization function at the zero energy, which is perturbative in $B$. Hence,
the pair-production width can be easily obtained from the latter by the inverse
Mellin transform. The implications of our approach are discussed.
| [
{
"created": "Wed, 23 Aug 2000 06:39:04 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Oct 2000 08:55:31 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kao",
"W. F.",
""
],
[
"Lin",
"Guey-Lin",
""
],
[
"Tseng",
"Jie-Jun",
""
]
] | We reexamine the process $\gamma\to e^++ e^-$ in a background magnetic field comparable to $B_c\equiv m_e^2/e$. This process is known to be non-perturbative in the magnetic-field strength. However, it can be shown that the {\it moments} of the above pair production width is proportional to the derivatives of photon polarization function at the zero energy, which is perturbative in $B$. Hence, the pair-production width can be easily obtained from the latter by the inverse Mellin transform. The implications of our approach are discussed. |
2210.09287 | Keping Xie | Brian Batell, Tathagata Ghosh, Tao Han, and Keping Xie | Heavy Neutral Leptons at the Electron-Ion Collider | 31 pages, 15 figures, and 4 tables | null | 10.1007/JHEP03(2023)020 | HRI-RECAPP-2022-006, PITT-PACC-2107 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The future Electron-Ion Collider (EIC) at Brookhaven National Laboratory,
along with its primary capacity to elucidate the nuclear structure, will offer
new opportunities to probe physics beyond the Standard Model coupled to the
electroweak sector. Among the best motivated examples of such new physics are
new heavy neutral leptons (HNLs), which are likely to play a key role in
neutrino mass generation and lepton number violation. We study the capability
of the EIC to search for HNLs, which can be produced in electron-proton
collisions through charged current interactions as a consequence of their
mixing with light neutrinos. We find that, with the EIC design energy and
integrated luminosity, one is able to probe HNLs in the mass range of 1
GeV$-100$ GeV with mixing angles down to the order of $10^{-4} - 10^{-3}$
through the prompt decay, and $10^{-6} - 10^{-4}$ via the displaced decay
signatures. We also consider the invisible mode where an HNL is undetected or
decaying to dark sector particles. One could potentially probe heavy HNLs for
mixing angles in the window $10^{-3}-10^{-2}$, provided SM background
systematics can be brought under control. These searches are complementary to
other probes of HNLs, such as neutrino-less double-$\beta$ decay, meson decay,
fixed-target, and high-energy collider experiments.
| [
{
"created": "Mon, 17 Oct 2022 17:46:13 GMT",
"version": "v1"
}
] | 2023-03-22 | [
[
"Batell",
"Brian",
""
],
[
"Ghosh",
"Tathagata",
""
],
[
"Han",
"Tao",
""
],
[
"Xie",
"Keping",
""
]
] | The future Electron-Ion Collider (EIC) at Brookhaven National Laboratory, along with its primary capacity to elucidate the nuclear structure, will offer new opportunities to probe physics beyond the Standard Model coupled to the electroweak sector. Among the best motivated examples of such new physics are new heavy neutral leptons (HNLs), which are likely to play a key role in neutrino mass generation and lepton number violation. We study the capability of the EIC to search for HNLs, which can be produced in electron-proton collisions through charged current interactions as a consequence of their mixing with light neutrinos. We find that, with the EIC design energy and integrated luminosity, one is able to probe HNLs in the mass range of 1 GeV$-100$ GeV with mixing angles down to the order of $10^{-4} - 10^{-3}$ through the prompt decay, and $10^{-6} - 10^{-4}$ via the displaced decay signatures. We also consider the invisible mode where an HNL is undetected or decaying to dark sector particles. One could potentially probe heavy HNLs for mixing angles in the window $10^{-3}-10^{-2}$, provided SM background systematics can be brought under control. These searches are complementary to other probes of HNLs, such as neutrino-less double-$\beta$ decay, meson decay, fixed-target, and high-energy collider experiments. |
2308.01482 | Amruta Mishra | Amruta Mishra, Ankit Kumar and S.P. Misra | Production cross-sections and Radiative Decay widths of Heavy Quarkonia
in magnetized matter | 32 pages, 9 figures, version to be published in Int. Jour. Mod. Phys.
E. arXiv admin note: text overlap with arXiv:2210.09192 | null | null | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | We study the production cross-sections and radiative decay widths of heavy
quarkonia (charmonia and bottomonia) in magnetized nuclear matter. The
production cross-sections of the $\psi(3770)$ and $\Upsilon(4S)$, from the
$D\bar D$ and $B\bar B$ scatterings respectively, are studied from the medium
modifications of the masses and partial decay widths to open charm (bottom)
mesons, of these heavy flavor mesons. Within a chiral effective model, the
masses of the vector and pseudoscalar charmonium (bottomonium) states are
calculated from the medium modification of a dilaton field, $\chi$, which
mimics the gluon condensates of QCD. In the presence of a magnetic field, there
is mixing of the pseudoscalar (P) meson and the longitudinal component of the
vector (V) meson (PV mixing), which leads to appreciable modifications of their
masses. The radiative decay widths of the vector (V) heavy quarkonia to the
pseudoscalar (P) mesons ($J/\psi\rightarrow \eta_c(1S) \gamma$,
$\psi(2S)\rightarrow \eta_c(2S) \gamma$ and $\psi(1D)\rightarrow \eta_c(2S)
\gamma$ for the charm sector and $\Upsilon(NS)\rightarrow \eta_b(NS)\gamma$,
$N$=1,2,3,4, for the bottom sector) in the magnetized asymmetric nuclear matter
are also investigated in the present work. The difference in the mass of the
transverse component from the longitudinal component of the vector meson,
arising due to PV mixing, is observed as a double peak structure in the
invariant mass spectrum of the production cross-section of $\psi(3770)$. The
modifications of the production cross-sections as well as the radiative decay
widths of the heavy quarkonia in the magnetized matter should have observable
consequences on the production of these heavy flavour mesons resulting from
ultra-relativistic peripheral heavy ion collision experiments, where the
created magnetic field can be extremely large.
| [
{
"created": "Thu, 3 Aug 2023 00:24:45 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Nov 2023 02:00:39 GMT",
"version": "v2"
}
] | 2023-11-22 | [
[
"Mishra",
"Amruta",
""
],
[
"Kumar",
"Ankit",
""
],
[
"Misra",
"S. P.",
""
]
] | We study the production cross-sections and radiative decay widths of heavy quarkonia (charmonia and bottomonia) in magnetized nuclear matter. The production cross-sections of the $\psi(3770)$ and $\Upsilon(4S)$, from the $D\bar D$ and $B\bar B$ scatterings respectively, are studied from the medium modifications of the masses and partial decay widths to open charm (bottom) mesons, of these heavy flavor mesons. Within a chiral effective model, the masses of the vector and pseudoscalar charmonium (bottomonium) states are calculated from the medium modification of a dilaton field, $\chi$, which mimics the gluon condensates of QCD. In the presence of a magnetic field, there is mixing of the pseudoscalar (P) meson and the longitudinal component of the vector (V) meson (PV mixing), which leads to appreciable modifications of their masses. The radiative decay widths of the vector (V) heavy quarkonia to the pseudoscalar (P) mesons ($J/\psi\rightarrow \eta_c(1S) \gamma$, $\psi(2S)\rightarrow \eta_c(2S) \gamma$ and $\psi(1D)\rightarrow \eta_c(2S) \gamma$ for the charm sector and $\Upsilon(NS)\rightarrow \eta_b(NS)\gamma$, $N$=1,2,3,4, for the bottom sector) in the magnetized asymmetric nuclear matter are also investigated in the present work. The difference in the mass of the transverse component from the longitudinal component of the vector meson, arising due to PV mixing, is observed as a double peak structure in the invariant mass spectrum of the production cross-section of $\psi(3770)$. The modifications of the production cross-sections as well as the radiative decay widths of the heavy quarkonia in the magnetized matter should have observable consequences on the production of these heavy flavour mesons resulting from ultra-relativistic peripheral heavy ion collision experiments, where the created magnetic field can be extremely large. |
hep-ph/9511466 | Debajyoti Choudhury | Debajyoti Choudhury | R-Parity Violation at LEP2 : Virtual Effects | LaTeX; 9 pages, 2 figures (uuencoded compressed postscript files
submitted through figures option) | Phys.Lett. B376 (1996) 201-204 | 10.1016/0370-2693(96)00272-9 | CERN-TH/95--250 | hep-ph | null | We investigate the ability of LEP2 to detect possible $R$-parity violation,
especially for the case where direct production cross-sections are too small
for all superparticles. We demonstrate that for coupling strengths allowed by
present experiments, sfermion-exchange diagrams can contribute significantly to
the $e^+ e^- \rightarrow f \bar{f} $ process. This would be a useful tool in
further constraining the parameter space. Similar arguments hold for
leptoquarks and dileptons as well.
| [
{
"created": "Thu, 30 Nov 1995 14:43:51 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Choudhury",
"Debajyoti",
""
]
] | We investigate the ability of LEP2 to detect possible $R$-parity violation, especially for the case where direct production cross-sections are too small for all superparticles. We demonstrate that for coupling strengths allowed by present experiments, sfermion-exchange diagrams can contribute significantly to the $e^+ e^- \rightarrow f \bar{f} $ process. This would be a useful tool in further constraining the parameter space. Similar arguments hold for leptoquarks and dileptons as well. |
1911.05104 | Gary Kapilevich | Gary Kapilevich | Double inclusive small-x gluon production and their azimuthal
correlations in a biased ensemble | 15 pages. Resubmitted 2/20/20, in line with referee comments for
upcoming publication to Physics Review D. A paragraph was added at the
beginning of the introduction, so to begin the paper with a broader
presentation of using biased ensembles to better understand various
observables in particle collisions | Phys. Rev. D 101, 034035 (2020) | 10.1103/PhysRevD.101.034035 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider double $gg\rightarrow g$ production in the presence of a bias on
the unintegrated gluon distribution of the colliding hadron or nuclei. Such
bias could be due to the selection of configurations with a greater number of
gluons or higher mean transverse momentum squared or, more generally, due to a
modified spectral shape of the gluon distribution in the hadrons. Hence, we
consider reweighted functional averages over the stochastic ensemble of small-x
gluons. We evaluate explicitly the double inclusive gluon transverse momentum
spectrum in high-energy collisions, and their azimuthal correlations, for a few
simple examples of biases.
| [
{
"created": "Tue, 12 Nov 2019 19:14:20 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Feb 2020 18:48:00 GMT",
"version": "v2"
}
] | 2020-03-04 | [
[
"Kapilevich",
"Gary",
""
]
] | We consider double $gg\rightarrow g$ production in the presence of a bias on the unintegrated gluon distribution of the colliding hadron or nuclei. Such bias could be due to the selection of configurations with a greater number of gluons or higher mean transverse momentum squared or, more generally, due to a modified spectral shape of the gluon distribution in the hadrons. Hence, we consider reweighted functional averages over the stochastic ensemble of small-x gluons. We evaluate explicitly the double inclusive gluon transverse momentum spectrum in high-energy collisions, and their azimuthal correlations, for a few simple examples of biases. |
1911.02255 | Subhasmita Mishra | Subhasmita Mishra | Majorana dark matter and neutrino mass with $S_3$ symmetry | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This model includes a minimal extension of the standard model with $S_3$ and
$Z_2$ symmetries to explain neutrino masses and mixing along with the dark
matter phenomenology. Neutrino phenomenology is explored, consistent with the
$3 \sigma$ observation of oscillation parameters and a nonzero reactor mixing
angle ($\theta_{13}$) is obtained. The $S_3$ singlet Majorana neutrino couples
to the third generation of leptons, gives a correct relic density compatible
with the Planck data. This model does not allow tree level direct detection,
therefore we discuss the loop level effective interaction with the nucleus
mediated by gauge boson. Also the constraints from the lepton flavor violating
rare decay mode is commented.
| [
{
"created": "Wed, 6 Nov 2019 08:49:58 GMT",
"version": "v1"
}
] | 2019-11-07 | [
[
"Mishra",
"Subhasmita",
""
]
] | This model includes a minimal extension of the standard model with $S_3$ and $Z_2$ symmetries to explain neutrino masses and mixing along with the dark matter phenomenology. Neutrino phenomenology is explored, consistent with the $3 \sigma$ observation of oscillation parameters and a nonzero reactor mixing angle ($\theta_{13}$) is obtained. The $S_3$ singlet Majorana neutrino couples to the third generation of leptons, gives a correct relic density compatible with the Planck data. This model does not allow tree level direct detection, therefore we discuss the loop level effective interaction with the nucleus mediated by gauge boson. Also the constraints from the lepton flavor violating rare decay mode is commented. |
hep-ph/9505417 | null | M. Thunman, G.Ingelman, P. Gondolo | Charm Production and High Energy Atmospheric Muon and Neutrino Fluxes | 30 pages, 13 postscript figures, available at
http://www3.tsl.uu.se/thep/papers/TSL-ISV-95-0120.ps.gz | Astropart.Phys.5:309-332,1996 | 10.1016/0927-6505(96)00033-3 | TSL/ISV-95-0120 (Revised) | hep-ph | null | Production of muons and neutrinos in cosmic ray interactions with the
atmosphere has been investigated with Monte Carlo models for hadronic
interactions. The resulting conventional muon and neutrino fluxes (from $\pi$
and $K$ decays) agree well with earlier calculations, whereas our prompt fluxes
from charm decays are significantly lower than earlier estimates. Charm
production is mainly considered as a well defined perturbative QCD process, but
we also investigate a hypothetical non-perturbative intrinsic charm component
in the proton. The lower charm rate implies better prospects for detecting very
high energy neutrinos from cosmic sources.
| [
{
"created": "Tue, 30 May 1995 13:24:44 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Feb 1996 09:59:05 GMT",
"version": "v2"
}
] | 2011-05-23 | [
[
"Thunman",
"M.",
""
],
[
"Ingelman",
"G.",
""
],
[
"Gondolo",
"P.",
""
]
] | Production of muons and neutrinos in cosmic ray interactions with the atmosphere has been investigated with Monte Carlo models for hadronic interactions. The resulting conventional muon and neutrino fluxes (from $\pi$ and $K$ decays) agree well with earlier calculations, whereas our prompt fluxes from charm decays are significantly lower than earlier estimates. Charm production is mainly considered as a well defined perturbative QCD process, but we also investigate a hypothetical non-perturbative intrinsic charm component in the proton. The lower charm rate implies better prospects for detecting very high energy neutrinos from cosmic sources. |
1402.0507 | Mu-Chun Chen | Mu-Chun Chen, Maximilian Fallbacher, K.T. Mahanthappa, Michael Ratz,
Andreas Trautner | CP Violation from Finite Groups | 45 pages, 3 figures | Nucl. Phys. B883 (2014) 267 | 10.1016/j.nuclphysb.2014.03.023 | UCI-TR-2014-01, TUM-HEP 929/14, FLAVOR-EU-64, CU-HEP-584 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the origin of CP violation in settings with a discrete (flavor)
symmetry $G$. We show that physical CP transformations always have to be
class-inverting automorphisms of $G$. This allows us to categorize finite
groups into three types: (i) Groups that do not exhibit such an automorphism
and, therefore, in generic settings, explicitly violate CP. In settings based
on such groups, CP violation can have pure group-theoretic origin and can be
related to the complexity of some Clebsch-Gordan coefficients. (ii) Groups for
which one can find a CP basis in which all the Clebsch-Gordan coefficients are
real. For such groups, imposing CP invariance restricts the phases of coupling
coefficients. (iii) Groups that do not admit real Clebsch-Gordan coefficients
but possess a class-inverting automorphism that can be used to define a proper
(generalized) CP transformation. For such groups, imposing CP invariance can
lead to an additional symmetry that forbids certain couplings. We make use of
the so-called twisted Frobenius-Schur indicator to distinguish between the
three types of discrete groups. With $\Delta(27)$, $T^{\prime}$, and
$\Sigma(72)$ we present one explicit example for each type of group, thereby
illustrating the CP properties of models based on them. We also show that
certain operations that have been dubbed generalized CP transformations in the
recent literature do not lead to physical CP conservation.
| [
{
"created": "Mon, 3 Feb 2014 21:00:14 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Chen",
"Mu-Chun",
""
],
[
"Fallbacher",
"Maximilian",
""
],
[
"Mahanthappa",
"K. T.",
""
],
[
"Ratz",
"Michael",
""
],
[
"Trautner",
"Andreas",
""
]
] | We discuss the origin of CP violation in settings with a discrete (flavor) symmetry $G$. We show that physical CP transformations always have to be class-inverting automorphisms of $G$. This allows us to categorize finite groups into three types: (i) Groups that do not exhibit such an automorphism and, therefore, in generic settings, explicitly violate CP. In settings based on such groups, CP violation can have pure group-theoretic origin and can be related to the complexity of some Clebsch-Gordan coefficients. (ii) Groups for which one can find a CP basis in which all the Clebsch-Gordan coefficients are real. For such groups, imposing CP invariance restricts the phases of coupling coefficients. (iii) Groups that do not admit real Clebsch-Gordan coefficients but possess a class-inverting automorphism that can be used to define a proper (generalized) CP transformation. For such groups, imposing CP invariance can lead to an additional symmetry that forbids certain couplings. We make use of the so-called twisted Frobenius-Schur indicator to distinguish between the three types of discrete groups. With $\Delta(27)$, $T^{\prime}$, and $\Sigma(72)$ we present one explicit example for each type of group, thereby illustrating the CP properties of models based on them. We also show that certain operations that have been dubbed generalized CP transformations in the recent literature do not lead to physical CP conservation. |
hep-ph/9707408 | null | B.-Q. Ma and S. J. Brodsky | The Spin and Flavor Content of Intrinsic Sea Quarks | LaTex, 12 pages, SLAC pub number corrected | null | null | SLAC-PUB-7501, BIHEP-TH-97-06 | hep-ph | null | The intrinsic quark-antiquark pairs generated by the minimal energy
nonperturbative meson-baryon fluctuations in the nucleon sea provide a
consistent framework for understanding a number of empirical anomalies observed
in the deep inelastic quark-parton structure of nucleons: the flavor asymmetry
of the nucleon sea implied by the violation of Gottfried sum rule, the proton
spin problem implied by the violation of the Ellis-Jaffe sum rule, and the
outstanding conflict between two different determinations of the strange quark
sea in the nucleon.
| [
{
"created": "Mon, 21 Jul 1997 19:20:57 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Jul 1997 16:28:50 GMT",
"version": "v2"
}
] | 2008-02-03 | [
[
"Ma",
"B. -Q.",
""
],
[
"Brodsky",
"S. J.",
""
]
] | The intrinsic quark-antiquark pairs generated by the minimal energy nonperturbative meson-baryon fluctuations in the nucleon sea provide a consistent framework for understanding a number of empirical anomalies observed in the deep inelastic quark-parton structure of nucleons: the flavor asymmetry of the nucleon sea implied by the violation of Gottfried sum rule, the proton spin problem implied by the violation of the Ellis-Jaffe sum rule, and the outstanding conflict between two different determinations of the strange quark sea in the nucleon. |
2101.01278 | Joshua Martin | Joshua D. Martin, J. Carlson, Vincenzo Cirigliano, and Huaiyu Duan | Fast flavor oscillations in dense neutrino media with collisions | 12 pages, 6 figures | Phys. Rev. D 103, 063001 (2021) | 10.1103/PhysRevD.103.063001 | LA-UR-20-30504 | hep-ph astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the impact of the nonzero neutrino splitting and elastic
neutrino-nucleon collisions on fast neutrino oscillations. Our calculations
confirm that a small neutrino mass splitting and the neutrino mass hierarchy
have very little effect on fast oscillation waves. We also demonstrate
explicitly that fast oscillations remain largely unaffected for the
time/distance scales that are much smaller than the neutrino mean free path but
are damped on larger scales. This damping originates from both the direct
modification of the dispersion relation of the oscillation waves in the
neutrino medium and the flattening of the neutrino angular distributions over
time. Our work suggests that fast neutrino oscillation waves produced near the
neutrino sphere can propagate essentially unimpeded which may have
ramifications in various aspects of the supernova physics.
| [
{
"created": "Mon, 4 Jan 2021 23:23:09 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Mar 2021 18:24:58 GMT",
"version": "v2"
}
] | 2021-03-02 | [
[
"Martin",
"Joshua D.",
""
],
[
"Carlson",
"J.",
""
],
[
"Cirigliano",
"Vincenzo",
""
],
[
"Duan",
"Huaiyu",
""
]
] | We investigate the impact of the nonzero neutrino splitting and elastic neutrino-nucleon collisions on fast neutrino oscillations. Our calculations confirm that a small neutrino mass splitting and the neutrino mass hierarchy have very little effect on fast oscillation waves. We also demonstrate explicitly that fast oscillations remain largely unaffected for the time/distance scales that are much smaller than the neutrino mean free path but are damped on larger scales. This damping originates from both the direct modification of the dispersion relation of the oscillation waves in the neutrino medium and the flattening of the neutrino angular distributions over time. Our work suggests that fast neutrino oscillation waves produced near the neutrino sphere can propagate essentially unimpeded which may have ramifications in various aspects of the supernova physics. |
2207.01717 | Dimitri Colferai Prof | Dimitri Colferai | Triple (and quadruple) soft-gluon radiation in QCD hard scattering | 8 pages, 2 figures, proceedings for Loops and Legs 2022 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the radiation of three soft gluons in a generic process for
multiparton hard scattering in QCD. In the soft limit the corresponding
scattering amplitude has a singular behaviour that is factorized and controlled
by a colorful soft current. We compute the tree-level current for triple
soft-gluon emission from both massless and massive hard partons. The
three-gluon current is expressed in terms of maximally non-abelian irreducible
correlations. We compute the soft behaviour of squared amplitudes and the
colour correlations produced by the squared current. The radiation of one and
two soft gluons leads to colour dipole correlations. Triple soft-gluon
radiation produces in addition colour quadrupole correlations between the hard
partons. We examine the soft and collinear singularities of the squared current
in various energy ordered and angular ordered regions. We discuss some features
of soft radiation to all-loop orders for processes with two and three hard
partons. Considering triple soft-gluon radiation from three hard partons,
colour quadrupole interactions break the Casimir scaling symmetry between
quarks and gluons. We also present some results on the radiation of four soft
gluons from two hard partons, and we discuss the colour monster contribution
and its relation with the violation (and generalization) of Casimir scaling. We
also compute the first correction of $(1/N_c^2)$ to the eikonal formula for
multiple soft-gluon radiation with strong energy ordering from two hard gluons.
| [
{
"created": "Mon, 4 Jul 2022 20:42:14 GMT",
"version": "v1"
}
] | 2022-07-06 | [
[
"Colferai",
"Dimitri",
""
]
] | We consider the radiation of three soft gluons in a generic process for multiparton hard scattering in QCD. In the soft limit the corresponding scattering amplitude has a singular behaviour that is factorized and controlled by a colorful soft current. We compute the tree-level current for triple soft-gluon emission from both massless and massive hard partons. The three-gluon current is expressed in terms of maximally non-abelian irreducible correlations. We compute the soft behaviour of squared amplitudes and the colour correlations produced by the squared current. The radiation of one and two soft gluons leads to colour dipole correlations. Triple soft-gluon radiation produces in addition colour quadrupole correlations between the hard partons. We examine the soft and collinear singularities of the squared current in various energy ordered and angular ordered regions. We discuss some features of soft radiation to all-loop orders for processes with two and three hard partons. Considering triple soft-gluon radiation from three hard partons, colour quadrupole interactions break the Casimir scaling symmetry between quarks and gluons. We also present some results on the radiation of four soft gluons from two hard partons, and we discuss the colour monster contribution and its relation with the violation (and generalization) of Casimir scaling. We also compute the first correction of $(1/N_c^2)$ to the eikonal formula for multiple soft-gluon radiation with strong energy ordering from two hard gluons. |
1811.06019 | Ofri Telem | Csaba Cs\'aki, Gabriel Lee, Seung J. Lee, Salvator Lombardo, and Ofri
Telem | Continuum Naturalness | null | null | 10.1007/JHEP03(2019)142 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a novel class of composite Higgs models in which the top and gauge
partners responsible for cutting off the Higgs quadratic divergences form a
continuum. The continuum states are characterized by their spectral densities,
which should have a finite gap for realistic models. We present a concrete
example based on a warped extra dimension with a linear dilaton, where this
finite gap appears naturally. We derive the spectral densities in this model
and calculate the full Higgs potential for a phenomenologically viable
benchmark point, with percent level tuning. The continuum top and gauge
partners in this model evade all resonance searches at the LHC and yield
qualitatively different collider signals.
| [
{
"created": "Wed, 14 Nov 2018 19:17:35 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Apr 2019 02:13:29 GMT",
"version": "v2"
},
{
"created": "Mon, 27 May 2019 14:47:05 GMT",
"version": "v3"
}
] | 2019-05-28 | [
[
"Csáki",
"Csaba",
""
],
[
"Lee",
"Gabriel",
""
],
[
"Lee",
"Seung J.",
""
],
[
"Lombardo",
"Salvator",
""
],
[
"Telem",
"Ofri",
""
]
] | We present a novel class of composite Higgs models in which the top and gauge partners responsible for cutting off the Higgs quadratic divergences form a continuum. The continuum states are characterized by their spectral densities, which should have a finite gap for realistic models. We present a concrete example based on a warped extra dimension with a linear dilaton, where this finite gap appears naturally. We derive the spectral densities in this model and calculate the full Higgs potential for a phenomenologically viable benchmark point, with percent level tuning. The continuum top and gauge partners in this model evade all resonance searches at the LHC and yield qualitatively different collider signals. |
hep-ph/0408050 | Eugene Levin | Dmitri Kharzeev, Eugene Levin and Marzia Nardi | Color Glass Condensate at the LHC: hadron multiplicities in $pp$, $pA$
and $AA$ collisions | 26 pages, 8 figures | Nucl.Phys.A747:609-629,2005 | 10.1016/j.nuclphysa.2004.10.018 | BNL - NT - 04/26 | hep-ph | null | We make quantitative predictions for the rapidity and centrality dependencies
of hadron multiplicities in $AA$, $pA$ and $pp$ collisions at the LHC energies
basing on the ideas of parton saturation in the Color Glass Condensate.
| [
{
"created": "Tue, 3 Aug 2004 23:59:47 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Kharzeev",
"Dmitri",
""
],
[
"Levin",
"Eugene",
""
],
[
"Nardi",
"Marzia",
""
]
] | We make quantitative predictions for the rapidity and centrality dependencies of hadron multiplicities in $AA$, $pA$ and $pp$ collisions at the LHC energies basing on the ideas of parton saturation in the Color Glass Condensate. |
2011.08031 | Antonino Di Piazza | Tobias N. Wistisen, Christoph H. Keitel and Antonino Di Piazza | Transmutation of protons in a strong electromagnetic field | 22 pages, 2 figures. To appear in the Focus issue "Strong Field
Quantum Electrodynamics with high power lasers and particle beams" of New
Journal of Physics | New J. Phys. vol. 23, 065007 (2021) | 10.1088/1367-2630/abf705 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The process of turning a proton into a neutron, positron and
electron-neutrino in a strong plane-wave electromagnetic field is studied. This
process is forbidden in vacuum and is seen to feature an exponential
suppression factor which is non-perturbative in the field amplitude. The
suppression is alleviated when the proton experiences a field strength of about
ten times the Schwinger critical field in its rest frame or larger. Around this
threshold the lifetime of the proton, in its rest frame, is comparable to the
conventional neutron decay lifetime. As the field strength is increased, the
proton lifetime becomes increasingly short. We investigate possible scenarios
where this process may be observed in the laboratory using an ultra-intense
laser and a high-energy proton beam with the conclusion, however, that it would
be very challenging to observe this effect in the near future.
| [
{
"created": "Mon, 16 Nov 2020 15:30:19 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Jun 2021 06:09:10 GMT",
"version": "v2"
}
] | 2021-06-23 | [
[
"Wistisen",
"Tobias N.",
""
],
[
"Keitel",
"Christoph H.",
""
],
[
"Di Piazza",
"Antonino",
""
]
] | The process of turning a proton into a neutron, positron and electron-neutrino in a strong plane-wave electromagnetic field is studied. This process is forbidden in vacuum and is seen to feature an exponential suppression factor which is non-perturbative in the field amplitude. The suppression is alleviated when the proton experiences a field strength of about ten times the Schwinger critical field in its rest frame or larger. Around this threshold the lifetime of the proton, in its rest frame, is comparable to the conventional neutron decay lifetime. As the field strength is increased, the proton lifetime becomes increasingly short. We investigate possible scenarios where this process may be observed in the laboratory using an ultra-intense laser and a high-energy proton beam with the conclusion, however, that it would be very challenging to observe this effect in the near future. |
1602.05562 | Luis Alvarez-Ruso | L. Alvarez-Ruso, E. Hernandez, J. Nieves and M. J. Vicente Vacas | Present Status of Single Pion Production in Neutrino-Nucleus Reactions | 8 pages, 4 figures, prepared for the Proceedings of the 10th
International Workshop on Neutrino-Nucleus Interactions in the Few-GeV Region
(NuInt15) | null | 10.7566/JPSCP.12.010003 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Some of the recent progress in the physics of pion production induced by
neutrinos on nucleons and nuclei is reviewed from a theoretical perspective.
The importance of Watson's theorem to reconcile ANL and BNL data with the
off-diagonal Goldberger-Treiman relation for the $\Delta(1232)$ is discussed.
The disagreement between MiniBooNE data and theoretical calculations is
presented in the light of the new MINERvA data. The coherent pion production
data on $^{12}$C obtained by MINERvA are also compared to different microscopic
and PCAC models.
| [
{
"created": "Wed, 17 Feb 2016 20:37:03 GMT",
"version": "v1"
}
] | 2016-12-21 | [
[
"Alvarez-Ruso",
"L.",
""
],
[
"Hernandez",
"E.",
""
],
[
"Nieves",
"J.",
""
],
[
"Vacas",
"M. J. Vicente",
""
]
] | Some of the recent progress in the physics of pion production induced by neutrinos on nucleons and nuclei is reviewed from a theoretical perspective. The importance of Watson's theorem to reconcile ANL and BNL data with the off-diagonal Goldberger-Treiman relation for the $\Delta(1232)$ is discussed. The disagreement between MiniBooNE data and theoretical calculations is presented in the light of the new MINERvA data. The coherent pion production data on $^{12}$C obtained by MINERvA are also compared to different microscopic and PCAC models. |
0705.0486 | Christopher Gorham Lester | Benjamin C. Allanach, Christopher G. Lester | Sampling using a `bank' of clues | v1: 18 pages, 7 figures. v2: 22 pages, 9 figures: no changes to the
algorithm, but more example distributions are provided against which the
sampler is tested | Comput.Phys.Commun.179:256-266,2008 | 10.1016/j.cpc.2008.02.020 | DAMTP-2007-18, Cavendish-HEP-2007-02 | hep-ph physics.data-an | null | An easy-to-implement form of the Metropolis Algorithm is described which,
unlike most standard techniques, is well suited to sampling from multi-modal
distributions on spaces with moderate numbers of dimensions (order ten) in
environments typical of investigations into current constraints on
Beyond-the-Standard-Model physics. The sampling technique makes use of
pre-existing information (which can safely be of low or uncertain quality)
relating to the distribution from which it is desired to sample. This
information should come in the form of a ``bank'' or ``cache'' of space points
of which at least some may be expected to be near regions of interest in the
desired distribution. In practical circumstances such ``banks of clues'' are
easy to assemble from earlier work, aborted runs, discarded burn-in samples
from failed sampling attempts, or from prior scouting investigations. The
technique equilibrates between disconnected parts of the distribution without
user input. The algorithm is not lead astray by ``bad'' clues, but there is no
free lunch: performance gains will only be seen where clues are helpful.
| [
{
"created": "Thu, 3 May 2007 15:50:08 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Nov 2007 21:59:48 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Allanach",
"Benjamin C.",
""
],
[
"Lester",
"Christopher G.",
""
]
] | An easy-to-implement form of the Metropolis Algorithm is described which, unlike most standard techniques, is well suited to sampling from multi-modal distributions on spaces with moderate numbers of dimensions (order ten) in environments typical of investigations into current constraints on Beyond-the-Standard-Model physics. The sampling technique makes use of pre-existing information (which can safely be of low or uncertain quality) relating to the distribution from which it is desired to sample. This information should come in the form of a ``bank'' or ``cache'' of space points of which at least some may be expected to be near regions of interest in the desired distribution. In practical circumstances such ``banks of clues'' are easy to assemble from earlier work, aborted runs, discarded burn-in samples from failed sampling attempts, or from prior scouting investigations. The technique equilibrates between disconnected parts of the distribution without user input. The algorithm is not lead astray by ``bad'' clues, but there is no free lunch: performance gains will only be seen where clues are helpful. |
hep-ph/0110363 | Michael Trusov | R. B. Nevzorov and M. A. Trusov | Infrared quasi-fixed solutions in the NMSSM | 32 pages, 8 figures included, LaTeX 2e | Phys.Atom.Nucl. 64 (2001) 1299-1314; Yad.Fiz. 64 (2001) 1375-1390 | 10.1134/1.1389558 | null | hep-ph | null | The considerable part of the parameter space in the MSSM corresponding to the
infrared quasi fixed point scenario is almost excluded by LEP II bounds on the
lightest Higgs boson mass. In the NMSSM the mass of the lightest Higgs boson
reaches its maximum value in the strong Yukawa coupling limit when Yukawa
couplings are essentially larger than gauge ones at the Grand Unification
scale. In this limit the solutions of the renormalisation group equations are
attracted to the infrared and Hill type effective fixed lines or surfaces in
the Yukawa coupling parameter space. They are concentrated in the vicinity of
quasi fixed points for $Y_i(0)\to\infty$. However the solutions are attracted
to such points rather weakly. For this reason when all $Y_i(0)\sim 1$ the
solutions of the renormalisation group equations are gathered near a line in
the Hill type effective surface. In the paper the approximate solutions for the
NMSSM Yukawa couplings are given. The possibility of $b$--quark and
$\tau$--lepton Yukawa coupling unification at the scale $M_{X}$ is also
discussed.
| [
{
"created": "Sun, 28 Oct 2001 12:55:06 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Nevzorov",
"R. B.",
""
],
[
"Trusov",
"M. A.",
""
]
] | The considerable part of the parameter space in the MSSM corresponding to the infrared quasi fixed point scenario is almost excluded by LEP II bounds on the lightest Higgs boson mass. In the NMSSM the mass of the lightest Higgs boson reaches its maximum value in the strong Yukawa coupling limit when Yukawa couplings are essentially larger than gauge ones at the Grand Unification scale. In this limit the solutions of the renormalisation group equations are attracted to the infrared and Hill type effective fixed lines or surfaces in the Yukawa coupling parameter space. They are concentrated in the vicinity of quasi fixed points for $Y_i(0)\to\infty$. However the solutions are attracted to such points rather weakly. For this reason when all $Y_i(0)\sim 1$ the solutions of the renormalisation group equations are gathered near a line in the Hill type effective surface. In the paper the approximate solutions for the NMSSM Yukawa couplings are given. The possibility of $b$--quark and $\tau$--lepton Yukawa coupling unification at the scale $M_{X}$ is also discussed. |
hep-ph/0504034 | Niels R. Walet | Antti J. Niemi and Niels R. Walet | Splitting The Gluon? | Improved discussion of magnetic nature of phases; removed
unsubstantiated speculation about color confinement | Phys.Rev. D72 (2005) 054007 | 10.1103/PhysRevD.72.054007 | null | hep-ph cond-mat.supr-con hep-lat | null | In the strongly correlated environment of high-temperature cuprate
superconductors, the spin and charge degrees of freedom of an electron seem to
separate from each other. A similar phenomenon may be present in the strong
coupling phase of Yang-Mills theories, where a separation between the color
charge and the spin of a gluon could play a role in a mass gap formation. Here
we study the phase structure of a decomposed SU(2) Yang-Mills theory in a mean
field approximation, by inspecting quantum fluctuations in the condensate which
is formed by the color charge component of the gluon field. Our results suggest
that the decomposed theory has an involved phase structure. In particular,
there appears to be a phase which is quite reminiscent of the superconducting
phase in cuprates. We also find evidence that this phase is separated from the
asymptotically free theory by an intermediate pseudogap phase.
| [
{
"created": "Tue, 5 Apr 2005 15:57:51 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Aug 2005 13:11:26 GMT",
"version": "v2"
}
] | 2009-11-11 | [
[
"Niemi",
"Antti J.",
""
],
[
"Walet",
"Niels R.",
""
]
] | In the strongly correlated environment of high-temperature cuprate superconductors, the spin and charge degrees of freedom of an electron seem to separate from each other. A similar phenomenon may be present in the strong coupling phase of Yang-Mills theories, where a separation between the color charge and the spin of a gluon could play a role in a mass gap formation. Here we study the phase structure of a decomposed SU(2) Yang-Mills theory in a mean field approximation, by inspecting quantum fluctuations in the condensate which is formed by the color charge component of the gluon field. Our results suggest that the decomposed theory has an involved phase structure. In particular, there appears to be a phase which is quite reminiscent of the superconducting phase in cuprates. We also find evidence that this phase is separated from the asymptotically free theory by an intermediate pseudogap phase. |
1507.08427 | Altan Cakir | Altan Cakir (for the CMS and ATLAS Collaborations) | Searches for Beyond the Standard Model Physics at the LHC: Run1 Summary
and Run2 Prospects | Plenary talk at Flavor Physics and CP Violation Conference 24-29 May,
2015 Nagoya, Japan | PoS(FPCP2015)024 SISSA, CERN CDS CMS CR-2015/141 | null | CMS CR-2015/141 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The search for new physics is a major goal of the LHC physics program. As
excitement grows for the upcoming start of Run 2, I review the CMS and ATLAS
searches for physics beyond the Standard Model from Run 1 and present recent
analyses. These searches have covered a wide range of new physics scenarios
including Supersymmetry, new resonances, additional Higgs bosons, new hidden
sectors, other Dark Matter, and multi-charged particles. In addition to
reviewing some of the techniques that made the analyses possible, I will
summarize what we have learned from the results and briefly discuss prospects
for Run 2.
| [
{
"created": "Thu, 30 Jul 2015 09:13:27 GMT",
"version": "v1"
}
] | 2019-08-14 | [
[
"Cakir",
"Altan",
"",
"for the CMS and ATLAS Collaborations"
]
] | The search for new physics is a major goal of the LHC physics program. As excitement grows for the upcoming start of Run 2, I review the CMS and ATLAS searches for physics beyond the Standard Model from Run 1 and present recent analyses. These searches have covered a wide range of new physics scenarios including Supersymmetry, new resonances, additional Higgs bosons, new hidden sectors, other Dark Matter, and multi-charged particles. In addition to reviewing some of the techniques that made the analyses possible, I will summarize what we have learned from the results and briefly discuss prospects for Run 2. |
hep-ph/9610209 | null | Markus Peter | The static quark-antiquark potential in QCD to three loops | Latex, 11 pages, 3 figures included. The complete paper, including
figures, is also available via anonymous ftp at
ftp://ttpux2.physik.uni-karlsruhe.de/ , or via www at
http://www-ttp.physik.uni-karlsruhe.de/cgi-bin/preprints/ . Revised version,
essentially identical to the version published in Physical Review Letters | Phys.Rev.Lett. 78 (1997) 602-605 | 10.1103/PhysRevLett.78.602 | TTP96-37 | hep-ph | null | The static potential between an infinitely heavy quark and antiquark is
derived in the framework of perturbative QCD to three loops by performing a
full calculation of the two-loop diagrams and using the renormalization group.
The contribution of massless fermions is included.
| [
{
"created": "Tue, 1 Oct 1996 12:57:28 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Feb 1997 14:29:50 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Peter",
"Markus",
""
]
] | The static potential between an infinitely heavy quark and antiquark is derived in the framework of perturbative QCD to three loops by performing a full calculation of the two-loop diagrams and using the renormalization group. The contribution of massless fermions is included. |
hep-ph/0608076 | Luca Trentadue | Luca Trentadue | Measuring the Running of the Electromagnetic Coupling Alpha in Small
Angle Bhabha Scattering | 4 pages, talk given at the International Conference on Linear
Colliders - LCWS 2004, Paris, Carre' des Sciences, April 19-23, 2004 | null | null | null | hep-ph | null | We propose a method to determine the running of $\alpha_{QED}$ from the
measurement of small-angle Bhabha scattering. The method is suited to high
statistics experiments at $e^{+} e^{-}$ colliders, which are equipped with
luminometers in the appropriate angular region. We present a new simulation
code predicting small-angle Bhabha scattering. A detailed description of this
idea can be found in A.B. Arbuzov, D. Haidt, C. Matteuzzi, M. Paganoni and L.
Trentadue, The running of the electromagnetic coupling alpha in small-angle
Bhabha scattering, Eur. Phys. J. C34, 267 (2004).
| [
{
"created": "Mon, 7 Aug 2006 12:29:27 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Trentadue",
"Luca",
""
]
] | We propose a method to determine the running of $\alpha_{QED}$ from the measurement of small-angle Bhabha scattering. The method is suited to high statistics experiments at $e^{+} e^{-}$ colliders, which are equipped with luminometers in the appropriate angular region. We present a new simulation code predicting small-angle Bhabha scattering. A detailed description of this idea can be found in A.B. Arbuzov, D. Haidt, C. Matteuzzi, M. Paganoni and L. Trentadue, The running of the electromagnetic coupling alpha in small-angle Bhabha scattering, Eur. Phys. J. C34, 267 (2004). |
1008.0800 | Norbert Kaiser | N. Kaiser | Radiative corrections to neutral pion-pair production | 10 pages, 6 figures, submitted to Eur. Phys. J. A | Eur.Phys.J.A46:373-378,2010 | 10.1140/epja/i2010-11050-9 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the one-photon loop radiative corrections to the neutral
pion-pair photoproduction process $\pi^-\gamma \to \pi^-\pi^0\pi^0$. At leading
order this reaction is governed by the chiral pion-pion interaction. Since the
chiral $\pi^+\pi^-\to\pi^0\pi^0$ contact-vertex depends only on the final-state
invariant-mass it factors out of all photon-loop diagrams. We give analytical
expressions for the multiplicative correction factor $R\sim \alpha/2\pi$
arising from eight classes of contributing one-photon loop diagrams. An
electromagnetic counterterm has to be included in order to cancel the
ultraviolet divergences generated by the photon-loops. Infrared finiteness of
the virtual radiative corrections is achieved (in the standard way) by
including soft photon radiation below an energy cut-off $\lambda$. The
radiative corrections to the total cross section vary between $+2\%$ and $-2\%$
for center-of-mass energies from threshold up to $7m_\pi$. The finite part of
the electromagnetic counterterm gives an additional constant contribution of
about $1\%$, however with a large uncertainty.
| [
{
"created": "Wed, 4 Aug 2010 15:08:17 GMT",
"version": "v1"
}
] | 2010-12-06 | [
[
"Kaiser",
"N.",
""
]
] | We calculate the one-photon loop radiative corrections to the neutral pion-pair photoproduction process $\pi^-\gamma \to \pi^-\pi^0\pi^0$. At leading order this reaction is governed by the chiral pion-pion interaction. Since the chiral $\pi^+\pi^-\to\pi^0\pi^0$ contact-vertex depends only on the final-state invariant-mass it factors out of all photon-loop diagrams. We give analytical expressions for the multiplicative correction factor $R\sim \alpha/2\pi$ arising from eight classes of contributing one-photon loop diagrams. An electromagnetic counterterm has to be included in order to cancel the ultraviolet divergences generated by the photon-loops. Infrared finiteness of the virtual radiative corrections is achieved (in the standard way) by including soft photon radiation below an energy cut-off $\lambda$. The radiative corrections to the total cross section vary between $+2\%$ and $-2\%$ for center-of-mass energies from threshold up to $7m_\pi$. The finite part of the electromagnetic counterterm gives an additional constant contribution of about $1\%$, however with a large uncertainty. |
hep-ph/9903440 | Javier Magnin | J. Magnin and H.R. Christiansen | The $bar{d} - \bar{u}$ asymmetry of the proton in a Pion Cloud Model
approach | Final version. To appear in Phys. Rev. D | Phys.Rev. D61 (2000) 054006 | 10.1103/PhysRevD.61.054006 | CBPF-NF-009/99 | hep-ph | null | We study the $bar{d} - \bar{u}$ asymmetry of the proton in a model approach
in which hadronic fluctuations of the nucleon are generated through gluon
splitting and recombination mechanisms. Within this framework, it is shown that
the \ud asymmetry of the proton is consistently described by including only
nucleon fluctuations to $|\pi N>$ and $|\pi \Delta>$ bound states. Predictions
of the model closely agree with the recent experimental data of the E866/NuSea
Collaboration.
| [
{
"created": "Mon, 22 Mar 1999 13:58:26 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Mar 1999 21:14:40 GMT",
"version": "v2"
},
{
"created": "Thu, 4 Nov 1999 00:04:53 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"Magnin",
"J.",
""
],
[
"Christiansen",
"H. R.",
""
]
] | We study the $bar{d} - \bar{u}$ asymmetry of the proton in a model approach in which hadronic fluctuations of the nucleon are generated through gluon splitting and recombination mechanisms. Within this framework, it is shown that the \ud asymmetry of the proton is consistently described by including only nucleon fluctuations to $|\pi N>$ and $|\pi \Delta>$ bound states. Predictions of the model closely agree with the recent experimental data of the E866/NuSea Collaboration. |
1906.00014 | Christopher Verhaaren | John Terning and Christopher B. Verhaaren | Detecting Dark Matter with Aharonov-Bohm | 14 pages, 2 figures; Updated references and expanded discussion
agrees with published version | JHEP 1912 (2019) 152 | 10.1007/JHEP12(2019)152 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | While the evidence for dark matter continues to grow, the nature of the dark
matter remains a mystery. A dark $U(1)_D$ gauge theory can have a small kinetic
mixing with the visible photon which provides a portal to the dark sector.
Magnetic monopoles of the dark $U(1)_D$ can obtain small magnetic couplings to
our photon through this kinetic mixing. This coupling is only manifest below
the mass of the dark photon; at these scales the monopoles are bound together
by tubes of dark magnetic flux. These flux tubes can produce phase shifts in
Aharonov-Bohm type experiments. We outline how this scenario might be realized,
examine the existing constraints, and quantify the experimental sensitivity
required to detect magnetic dipole dark matter in this novel way.
| [
{
"created": "Fri, 31 May 2019 18:00:26 GMT",
"version": "v1"
},
{
"created": "Sat, 28 Dec 2019 22:28:36 GMT",
"version": "v2"
}
] | 2020-01-01 | [
[
"Terning",
"John",
""
],
[
"Verhaaren",
"Christopher B.",
""
]
] | While the evidence for dark matter continues to grow, the nature of the dark matter remains a mystery. A dark $U(1)_D$ gauge theory can have a small kinetic mixing with the visible photon which provides a portal to the dark sector. Magnetic monopoles of the dark $U(1)_D$ can obtain small magnetic couplings to our photon through this kinetic mixing. This coupling is only manifest below the mass of the dark photon; at these scales the monopoles are bound together by tubes of dark magnetic flux. These flux tubes can produce phase shifts in Aharonov-Bohm type experiments. We outline how this scenario might be realized, examine the existing constraints, and quantify the experimental sensitivity required to detect magnetic dipole dark matter in this novel way. |
1607.04053 | Yasuhiro Yamaguchi | Yasuhiro Yamaguchi and Tetsuo Hyodo | Quark mass dependence of H-dibaryon in $\Lambda\Lambda$ scattering | 12 pages, 13 figures, 1 table | Phys. Rev. C 94, 065207 (2016) | 10.1103/PhysRevC.94.065207 | YITP-16-83 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the quark mass dependence of the H-dibaryon in the strangeness
$S=-2$ baryon-baryon scattering. A low-energy effective field theory is used to
describe the coupled-channel scattering, in which the quark mass dependence is
incorporated so as to reproduce the lattice QCD data by the HAL QCD
collaboration in the SU(3) limit. We point out the existence of the
Castillejo-Dalitz-Dyson (CDD) pole in the $\Lambda\Lambda$ scattering amplitude
below the threshold in the SU(3) limit, which may cause the Ramsauer-Townsend
effect near the $N\Xi$ threshold at the physical point. The H-dibaryon is
unbound at the physical point, and a resonance appears just below the $N\Xi$
threshold. As a consequence of the coupled-channel dynamics, the pole
associated with the resonance is not continuously connected to the bound state
in the SU(3) limit. Through the extrapolation in quark masses, we show that the
unitary limit of the $\Lambda\Lambda$ scattering is achieved between the
physical point and the SU(3) limit. We discuss the possible realization of the
"H-matter" in the unphysical quark mass region.
| [
{
"created": "Thu, 14 Jul 2016 09:37:13 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Jan 2017 14:42:42 GMT",
"version": "v2"
}
] | 2017-01-04 | [
[
"Yamaguchi",
"Yasuhiro",
""
],
[
"Hyodo",
"Tetsuo",
""
]
] | We study the quark mass dependence of the H-dibaryon in the strangeness $S=-2$ baryon-baryon scattering. A low-energy effective field theory is used to describe the coupled-channel scattering, in which the quark mass dependence is incorporated so as to reproduce the lattice QCD data by the HAL QCD collaboration in the SU(3) limit. We point out the existence of the Castillejo-Dalitz-Dyson (CDD) pole in the $\Lambda\Lambda$ scattering amplitude below the threshold in the SU(3) limit, which may cause the Ramsauer-Townsend effect near the $N\Xi$ threshold at the physical point. The H-dibaryon is unbound at the physical point, and a resonance appears just below the $N\Xi$ threshold. As a consequence of the coupled-channel dynamics, the pole associated with the resonance is not continuously connected to the bound state in the SU(3) limit. Through the extrapolation in quark masses, we show that the unitary limit of the $\Lambda\Lambda$ scattering is achieved between the physical point and the SU(3) limit. We discuss the possible realization of the "H-matter" in the unphysical quark mass region. |
hep-ph/0301230 | Alejandro Gutierrez | A. Guti\'errez-Rodr\'iguez (Zacatecas University), M. A.
Hern\'andez-Ru\'iz (Zacatecas University), M. Maya (Puebla University) and M.
L. Ortega (Puebla University) | Pair Production and Angular Distribution of Helicity Flipped Neutrinos
in a Left-Right Symmetric Model | 16 pages, 7 figures | null | null | null | hep-ph | null | We assume that a massive Dirac neutrino is characteized by two
phenomenological parameters, a magnetic moment, and a charge radius, and we
calculate the cross-section of the scattering $e^+e^-\to \nu \bar \nu$ in a
left-right symmetric model. We also analyze the angular distribution of the
neutrino (antineutrino) with respect to the original direction of the electron
(positron) to different state of helicity of the neutrino. We find that the
favored directions for the neutrino (antineutrino) with respect to the electron
(positron) is forward $(\theta =0)$ and backward $(\theta= \pi)$, and is not
very probable in the perpendicular direction $(\theta = \frac{\pi}{2})$. The
calculation is for $\phi = -0.005$ and $M_{Z_2}=500$ $GeV$, parameters of the
Left-Right symmetric model.
| [
{
"created": "Mon, 27 Jan 2003 18:56:16 GMT",
"version": "v1"
}
] | 2016-08-16 | [
[
"Gutiérrez-Rodríguez",
"A.",
"",
"Zacatecas University"
],
[
"Hernández-Ruíz",
"M. A.",
"",
"Zacatecas University"
],
[
"Maya",
"M.",
"",
"Puebla University"
],
[
"Ortega",
"M. L.",
"",
"Puebla University"
]
] | We assume that a massive Dirac neutrino is characteized by two phenomenological parameters, a magnetic moment, and a charge radius, and we calculate the cross-section of the scattering $e^+e^-\to \nu \bar \nu$ in a left-right symmetric model. We also analyze the angular distribution of the neutrino (antineutrino) with respect to the original direction of the electron (positron) to different state of helicity of the neutrino. We find that the favored directions for the neutrino (antineutrino) with respect to the electron (positron) is forward $(\theta =0)$ and backward $(\theta= \pi)$, and is not very probable in the perpendicular direction $(\theta = \frac{\pi}{2})$. The calculation is for $\phi = -0.005$ and $M_{Z_2}=500$ $GeV$, parameters of the Left-Right symmetric model. |
2103.03050 | Dao-Neng Gao | Dao-Neng Gao and Xi Gong | Exclusive rare Higgs decays into lepton pair and light mesons | 12 pages, 4 figures | null | 10.1016/j.physletb.2021.136348 | USTC-ICTS/PCFT-21-09 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Exclusive rare Higgs decays into lepton pair plus one light hadron, such as
$h\to \rho^0(\omega)\ell\bar{\ell}$, $h\to \pi^0\ell\bar{\ell}$, $h\to \pi^+
(K^+)\ell^-\bar{\nu}_\ell$, and $h\to \rho^+(K^{*+})\ell^-\bar{\nu}_\ell$, have
been explored in the standard model. Decay amplitudes are dominantly from the
Higgs couplings to gauge bosons and to charged leptons, and their branching
ratios are predicted in the range of $10^{-8}\sim 10^{-5}$. We have also
analyzed the differential dilepton invariant mass and angular distributions of
$h\to \rho^0 \ell^+\ell^-$ decays. It will be challenging to search for these
rare processes. Nevertheless, experimental studies of them, in particular,
$h\to \rho^0\ell^+\ell^-$ with $\ell=e,\mu$, might be interesting both to help
deepen our understanding of the standard model and to probe new physics beyond
the standard model in the future high-precision experiments.
| [
{
"created": "Thu, 4 Mar 2021 14:15:47 GMT",
"version": "v1"
}
] | 2021-05-12 | [
[
"Gao",
"Dao-Neng",
""
],
[
"Gong",
"Xi",
""
]
] | Exclusive rare Higgs decays into lepton pair plus one light hadron, such as $h\to \rho^0(\omega)\ell\bar{\ell}$, $h\to \pi^0\ell\bar{\ell}$, $h\to \pi^+ (K^+)\ell^-\bar{\nu}_\ell$, and $h\to \rho^+(K^{*+})\ell^-\bar{\nu}_\ell$, have been explored in the standard model. Decay amplitudes are dominantly from the Higgs couplings to gauge bosons and to charged leptons, and their branching ratios are predicted in the range of $10^{-8}\sim 10^{-5}$. We have also analyzed the differential dilepton invariant mass and angular distributions of $h\to \rho^0 \ell^+\ell^-$ decays. It will be challenging to search for these rare processes. Nevertheless, experimental studies of them, in particular, $h\to \rho^0\ell^+\ell^-$ with $\ell=e,\mu$, might be interesting both to help deepen our understanding of the standard model and to probe new physics beyond the standard model in the future high-precision experiments. |
hep-ph/9706241 | Sridhar K. | K. Sridhar (TIFR, Bombay, India) | h_c production at the Tevatron | Latex file (4 pages); Talk presented at the XXXII Rencontres de
Moriond, ``QCD and High Energy Interactions'', March 22-29, 1997, Les Arcs,
France | null | null | TIFR/TH/97-27 | hep-ph | null | Non-Relativistic QCD (NRQCD) has provided a consistent framework for the
physics of quarkonia. The colour-octet Fock components predicted by NRQCD have
important implications for the phenomenology of quarkonium production in
experiments. We have considered the consequences of the colour-octet channels
for the production of the $^1P_1$ charmonium state, $h_c$, at large-p_T at the
Tevatron. The colour-octet contributions to this state are found to be dominant
and give a reasonably large rate for the production of $h_c$. This should make
it feasible to look for this resonance in the $J/\psi +\pi$ decay channel. The
observation of $h_c$ is interesting in its own right, since its existence has
yet to be experimentally confirmed. Moreover, this rate is a prediction of
NRQCD, and the observation of the $h_c$ at the Tevatron can, therefore, be used
as a test of NRQCD.
| [
{
"created": "Wed, 4 Jun 1997 11:28:55 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Sridhar",
"K.",
"",
"TIFR, Bombay, India"
]
] | Non-Relativistic QCD (NRQCD) has provided a consistent framework for the physics of quarkonia. The colour-octet Fock components predicted by NRQCD have important implications for the phenomenology of quarkonium production in experiments. We have considered the consequences of the colour-octet channels for the production of the $^1P_1$ charmonium state, $h_c$, at large-p_T at the Tevatron. The colour-octet contributions to this state are found to be dominant and give a reasonably large rate for the production of $h_c$. This should make it feasible to look for this resonance in the $J/\psi +\pi$ decay channel. The observation of $h_c$ is interesting in its own right, since its existence has yet to be experimentally confirmed. Moreover, this rate is a prediction of NRQCD, and the observation of the $h_c$ at the Tevatron can, therefore, be used as a test of NRQCD. |
hep-ph/9309245 | Andrzej Czarnecki | Andrzej Czarnecki and Andrei I. Davydychev | Two-loop renormalization group analysis of hadronic decays of a charged
Higgs boson | 10 pages + 4 figures, PostScript) | Phys.Lett. B325 (1994) 435-440 | 10.1016/0370-2693(94)90037-X | Alberta Thy-38-93 | hep-ph | null | We calculate next-to-leading QCD corrections to the decay $H^+ \to u\bar d$
for generic up and down quarks in the final state. A recently developed
algorithm for evaluation of massive two-loop Feynman diagrams is employed to
calculate renormalization constants of the charged Higgs boson. The origin and
summation of large logarithmic corrections to the decay rate of the top quark
into a lighter charged Higgs boson is also explained.
| [
{
"created": "Wed, 8 Sep 1993 22:08:07 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Czarnecki",
"Andrzej",
""
],
[
"Davydychev",
"Andrei I.",
""
]
] | We calculate next-to-leading QCD corrections to the decay $H^+ \to u\bar d$ for generic up and down quarks in the final state. A recently developed algorithm for evaluation of massive two-loop Feynman diagrams is employed to calculate renormalization constants of the charged Higgs boson. The origin and summation of large logarithmic corrections to the decay rate of the top quark into a lighter charged Higgs boson is also explained. |
2102.08943 | Valery Lyubovitskij | Valery E. Lyubovitskij, Fabian Wunder, Alexey S. Zhevlakov | New ideas for handling of loop and angular integrals in D-dimensions in
QCD | 134 pages, 8 figures | JHEP 06 (2021) 066 | 10.1007/JHEP06(2021)066 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We discuss new ideas for consideration of loop diagrams and angular integrals
in $D$-dimensions in QCD. In case of loop diagrams, we propose the covariant
formalism of expansion of tensorial loop integrals into the orthogonal basis of
linear combinations of external momenta. It gives a very simple presentation
for the final results and is more convenient for calculations on computer
algebra systems. In case of angular integrals we demonstrate how to simplify
the integration of differential cross sections over polar angles. Also we
derive the recursion relations, which allow to reduce all occurring angular
integrals to a short set of basic scalar integrals. All order
$\epsilon$-expansion is given for all angular integrals with up to two
denominators based on the expansion of the basic integrals and using recursion
relations. A geometric picture for partial fractioning is developed which
provides a new rotational invariant algorithm to reduce the number of
denominators.
| [
{
"created": "Wed, 17 Feb 2021 18:56:46 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Jun 2021 10:11:24 GMT",
"version": "v2"
}
] | 2021-06-11 | [
[
"Lyubovitskij",
"Valery E.",
""
],
[
"Wunder",
"Fabian",
""
],
[
"Zhevlakov",
"Alexey S.",
""
]
] | We discuss new ideas for consideration of loop diagrams and angular integrals in $D$-dimensions in QCD. In case of loop diagrams, we propose the covariant formalism of expansion of tensorial loop integrals into the orthogonal basis of linear combinations of external momenta. It gives a very simple presentation for the final results and is more convenient for calculations on computer algebra systems. In case of angular integrals we demonstrate how to simplify the integration of differential cross sections over polar angles. Also we derive the recursion relations, which allow to reduce all occurring angular integrals to a short set of basic scalar integrals. All order $\epsilon$-expansion is given for all angular integrals with up to two denominators based on the expansion of the basic integrals and using recursion relations. A geometric picture for partial fractioning is developed which provides a new rotational invariant algorithm to reduce the number of denominators. |
2111.03357 | Jordi Salvado | Carlos A. Arg\"uelles and Jordi Salvado | Sterile neutrinos with neutrino telescopes | 10 pages, 5 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Searches for light sterile neutrinos are motivated by the unexpected
observation of electron neutrino appearance in short-baseline experiments, such
as the Liquid Scintillator Neutrino Detector (LSND) and the Mini Booster
Neutrino Experiment (MiniBooNE). In light of these unexpected results, a
campaign using natural and anthropogenic sources to find light --
mass-squared-difference around 1 eV$^{2}$ -- sterile neutrinos is underway.
Among the natural sources, atmospheric neutrinos provide a unique gateway to
search for sterile neutrinos due to the broad range of baseline-to-energy
ratios, $L/E$, and the presence of significant matter effects. Since the
atmospheric neutrino flux rapidly falls with energy, studying its highest
energy component requires gigaton-scale neutrino detectors. These detectors --
often known as neutrino telescopes since they are designed to observe tiny
astrophysical neutrino fluxes -- have performed searches for light sterile
neutrinos and have found no significant signal to date. This brief review
summarizes the current status of searches for light sterile neutrinos with
neutrino telescopes deployed in solid and liquid water.
| [
{
"created": "Fri, 5 Nov 2021 09:59:51 GMT",
"version": "v1"
}
] | 2021-11-08 | [
[
"Argüelles",
"Carlos A.",
""
],
[
"Salvado",
"Jordi",
""
]
] | Searches for light sterile neutrinos are motivated by the unexpected observation of electron neutrino appearance in short-baseline experiments, such as the Liquid Scintillator Neutrino Detector (LSND) and the Mini Booster Neutrino Experiment (MiniBooNE). In light of these unexpected results, a campaign using natural and anthropogenic sources to find light -- mass-squared-difference around 1 eV$^{2}$ -- sterile neutrinos is underway. Among the natural sources, atmospheric neutrinos provide a unique gateway to search for sterile neutrinos due to the broad range of baseline-to-energy ratios, $L/E$, and the presence of significant matter effects. Since the atmospheric neutrino flux rapidly falls with energy, studying its highest energy component requires gigaton-scale neutrino detectors. These detectors -- often known as neutrino telescopes since they are designed to observe tiny astrophysical neutrino fluxes -- have performed searches for light sterile neutrinos and have found no significant signal to date. This brief review summarizes the current status of searches for light sterile neutrinos with neutrino telescopes deployed in solid and liquid water. |
1210.7316 | Yakov Azimov | Ya. Azimov | Interference of resonances and observation of the \Theta^{+}-pentaquark | 7 pages, 1 figure, LATEX, uses hsqcd.cls (included); presented at the
International Workshop HSQCD 2012, St.Petersburg, Russia, 4--8 July, 2012; to
appear in the Proceedings | Published in the Proceedings of the International Workshop HSQCD
2012, eds. V.T.Kim and L.N.Lipatov (PNPI, Gatchina, 2012) p.158 | null | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | After brief discussion of how the quantum interference may influence
manifestations of resonances, description is given of the recent experimental
evidence for possible manifestation of the \Theta^{+}-photoproduction in
interference with the \phi-photoproduction.
| [
{
"created": "Sat, 27 Oct 2012 11:56:34 GMT",
"version": "v1"
}
] | 2014-01-03 | [
[
"Azimov",
"Ya.",
""
]
] | After brief discussion of how the quantum interference may influence manifestations of resonances, description is given of the recent experimental evidence for possible manifestation of the \Theta^{+}-photoproduction in interference with the \phi-photoproduction. |
1108.0241 | Qiang Zhao | Ze-kun Guo and Qiang Zhao | Novel insights into the $\gamma\gamma^*\to \pi^0$ transition form factor | Revtex, 6 pages and 4 eps figures; Extended version accepted by Eur.
Phys. J. C | null | 10.1140/epjc/s10052-012-1964-7 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | BaBar's observation of significant deviations of the pion transition form
factor (TFF) from the asymptotic expectation with $Q^2>9$ GeV$^2$ has brought a
serious crisis to a fundamental picture established for such a simplest
$q\bar{q}$ system by perturbative QCD, i.e. the dominance of collinear
factorization at high momentum transfers for the pion TFF. We show that
non-factorizable contributions due to open flavors in $\gamma\gamma^*\to\pi^0$
could be an important source that contaminates the pQCD asymptotic limit and
causes such deviations with $Q^2>9$ GeV$^2$. Within an effective Lagrangian
approach, the non-factorizable amplitudes can be related to intermediate hadron
loops, i.e. $K^{(*)}$ and $D^{(*)}$ etc, and their corrections to the $\pi^0$
and $\eta$ TFFs can be estimated.
| [
{
"created": "Mon, 1 Aug 2011 05:56:33 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Mar 2012 16:34:58 GMT",
"version": "v2"
}
] | 2015-05-30 | [
[
"Guo",
"Ze-kun",
""
],
[
"Zhao",
"Qiang",
""
]
] | BaBar's observation of significant deviations of the pion transition form factor (TFF) from the asymptotic expectation with $Q^2>9$ GeV$^2$ has brought a serious crisis to a fundamental picture established for such a simplest $q\bar{q}$ system by perturbative QCD, i.e. the dominance of collinear factorization at high momentum transfers for the pion TFF. We show that non-factorizable contributions due to open flavors in $\gamma\gamma^*\to\pi^0$ could be an important source that contaminates the pQCD asymptotic limit and causes such deviations with $Q^2>9$ GeV$^2$. Within an effective Lagrangian approach, the non-factorizable amplitudes can be related to intermediate hadron loops, i.e. $K^{(*)}$ and $D^{(*)}$ etc, and their corrections to the $\pi^0$ and $\eta$ TFFs can be estimated. |
2003.01788 | Ivan Ni\v{s}and\v{z}i\'c | Aliaksei Kachanovich, Ulrich Nierste, Ivan Ni\v{s}and\v{z}i\'c | Higgs portal to dark matter and $B\to K^{(*)}$ decays | 9 pages, 4 figures. v.2: minor clarifications, added Table 1, added
references, acknowledgements extended | null | 10.1140/epjc/s10052-020-8240-z | TTP20-010 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider a Higgs portal model in which the 125-GeV Higgs boson mixes with
a light singlet mediator $h_2$ coupling to particles of a Dark Sector and study
potential $b\to s h_2$ decays in the Belle II experiment. Multiplying the
gauge-dependent off-shell Standard-Model $b$-$s$-Higgs vertex with the sine of
the Higgs mixing angle does not give the correct $b$-$s$-$h_2$ vertex. We
clarify this issue by calculating the $b$-$s$-$h_2$ vertex in an arbitrary
$R_\xi$ gauge and demonstrate how the $\xi$ dependence cancels from physical
decay rates involving an on-shell or off-shell $h_2$. Then we revisit the $b\to
s h_2$ phenomenology and point out that a simultaneous study of $B\to K^* h_2$
and $B\to K h_2$ helps to discriminate between the Higgs portal and alternative
models of the Dark Sector. We further advocate for the use of the $h_2$
lifetime information contained in displaced-vertex data with $h_2$ decaying
back to Standard-Model particles to better constrain the $h_2$ mass or to
reveal additional $h_2$ decay modes into long-lived particles.
| [
{
"created": "Tue, 3 Mar 2020 20:51:19 GMT",
"version": "v1"
},
{
"created": "Mon, 23 Mar 2020 13:25:15 GMT",
"version": "v2"
}
] | 2020-08-26 | [
[
"Kachanovich",
"Aliaksei",
""
],
[
"Nierste",
"Ulrich",
""
],
[
"Nišandžić",
"Ivan",
""
]
] | We consider a Higgs portal model in which the 125-GeV Higgs boson mixes with a light singlet mediator $h_2$ coupling to particles of a Dark Sector and study potential $b\to s h_2$ decays in the Belle II experiment. Multiplying the gauge-dependent off-shell Standard-Model $b$-$s$-Higgs vertex with the sine of the Higgs mixing angle does not give the correct $b$-$s$-$h_2$ vertex. We clarify this issue by calculating the $b$-$s$-$h_2$ vertex in an arbitrary $R_\xi$ gauge and demonstrate how the $\xi$ dependence cancels from physical decay rates involving an on-shell or off-shell $h_2$. Then we revisit the $b\to s h_2$ phenomenology and point out that a simultaneous study of $B\to K^* h_2$ and $B\to K h_2$ helps to discriminate between the Higgs portal and alternative models of the Dark Sector. We further advocate for the use of the $h_2$ lifetime information contained in displaced-vertex data with $h_2$ decaying back to Standard-Model particles to better constrain the $h_2$ mass or to reveal additional $h_2$ decay modes into long-lived particles. |
hep-ph/9807486 | null | V. P. Gusynin and A. V. Smilga | Electron Self-Energy in Strong Magnetic Field: Summation of Double
Logarithmic Terms | 9 pages, revtex, 6 eps figures | Phys.Lett.B450:267-274,1999 | 10.1016/S0370-2693(99)00145-8 | NORDITA 98/39-HE | hep-ph | null | We study the electron self--energy in a strong magnetic field when the
parameter \eta\equiv (\alpha/2\pi) \ln^2 (eB/m^2_0) \sim 1 and explore the
transition between the perturbative regime \eta<<1 and the nonperturbative
massless QED regime \eta>>1 where chiral symmetry is broken spontaneously and
electrons acquire the dynamically induced mass.
| [
{
"created": "Fri, 24 Jul 1998 15:08:48 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Gusynin",
"V. P.",
""
],
[
"Smilga",
"A. V.",
""
]
] | We study the electron self--energy in a strong magnetic field when the parameter \eta\equiv (\alpha/2\pi) \ln^2 (eB/m^2_0) \sim 1 and explore the transition between the perturbative regime \eta<<1 and the nonperturbative massless QED regime \eta>>1 where chiral symmetry is broken spontaneously and electrons acquire the dynamically induced mass. |
1812.11372 | Zhi-Qing Zhang | Zhi-Qing Zhang, Hongxia Guo | Three body radiative decay $B_s\to \phi \bar K^0 \gamma$ in the PQCD
approach | 17 pages,6 figures, Accepted for publication in EPJC | Eur.Phys.J.C 79, 59 (2019) | 10.1140/epjc/s10052-019-6554-5 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the three body radiative decay $B_s\to \phi \bar K^0 \gamma$ by
introducing the $\phi K$ pair distribution amplitudes (DAs) in the perturbative
QCD approach. This nonperturbative inputs, the two meson DAs, is very important
to simplify the calculations. Besides the dominant electromagnetic penguin
operator $O_{7\gamma}$, the subleading contributions from chromomagnetic
penguin operator $O_{8g}$, quark-loop corrections and annihilation type
amplitudes are also considered. We find that the branching ratio for the decay
$B_s\to \phi \bar K^0 \gamma$ is about
$(9.26^{+1.79+3.12+0.64}_{-1.61-3.86-0.49})\times10^{-8}$, which is much
smaller compared with that for the decay $B^0\to \phi K^0\gamma$. It is mainly
because that the former decay induces by $b\to d\gamma$ with small CKM matrix
element being proportional to $\lambda^3$. The prediction for the direct CP
asymmetry is $A^{dir}_{CP}(B_s\to \phi \bar K^0
\gamma)=(-4.1^{+0.4+1.7+0.2}_{-0.6-1.2-0.1})\%$, which is well consistent with
the result from the U-spin symmetry approach. we also predict the $B_s \to\phi
\bar K^0\gamma$ decay spectrum, which exhibits a maximu at the $\phi K$
invariant masss around 1.95 GeV.
| [
{
"created": "Sat, 29 Dec 2018 14:46:51 GMT",
"version": "v1"
}
] | 2019-04-23 | [
[
"Zhang",
"Zhi-Qing",
""
],
[
"Guo",
"Hongxia",
""
]
] | We study the three body radiative decay $B_s\to \phi \bar K^0 \gamma$ by introducing the $\phi K$ pair distribution amplitudes (DAs) in the perturbative QCD approach. This nonperturbative inputs, the two meson DAs, is very important to simplify the calculations. Besides the dominant electromagnetic penguin operator $O_{7\gamma}$, the subleading contributions from chromomagnetic penguin operator $O_{8g}$, quark-loop corrections and annihilation type amplitudes are also considered. We find that the branching ratio for the decay $B_s\to \phi \bar K^0 \gamma$ is about $(9.26^{+1.79+3.12+0.64}_{-1.61-3.86-0.49})\times10^{-8}$, which is much smaller compared with that for the decay $B^0\to \phi K^0\gamma$. It is mainly because that the former decay induces by $b\to d\gamma$ with small CKM matrix element being proportional to $\lambda^3$. The prediction for the direct CP asymmetry is $A^{dir}_{CP}(B_s\to \phi \bar K^0 \gamma)=(-4.1^{+0.4+1.7+0.2}_{-0.6-1.2-0.1})\%$, which is well consistent with the result from the U-spin symmetry approach. we also predict the $B_s \to\phi \bar K^0\gamma$ decay spectrum, which exhibits a maximu at the $\phi K$ invariant masss around 1.95 GeV. |
hep-ph/9702275 | null | Eduard Masso and Ramon Toldra | New Constraints on a Light Spinless Particle Coupled to Photons | 7 pages, 1 postscript figure | Phys.Rev. D55 (1997) 7967-7969 | 10.1103/PhysRevD.55.7967 | UAB-FT-409 | hep-ph astro-ph | null | We obtain new stringent constraints on a light spinless particle phi coupled
only to photons at low energies, considering its effects on the extragalactic
photon background, the blackbody spectrum of the CMBR and the cosmological
abundance of deuterium.
| [
{
"created": "Thu, 6 Feb 1997 17:47:31 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Masso",
"Eduard",
""
],
[
"Toldra",
"Ramon",
""
]
] | We obtain new stringent constraints on a light spinless particle phi coupled only to photons at low energies, considering its effects on the extragalactic photon background, the blackbody spectrum of the CMBR and the cosmological abundance of deuterium. |
1001.1596 | Tomohiro Matsuda | Tomohiro Matsuda | Inflation, modulation and baryogenesis with warm directions | 6 pages, 4 figures, problems in figures are fixed | null | null | null | hep-ph astro-ph.CO gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There are many flat directions in SUSY models, which may dissipate their
energy and source the radiation background during inflation. However, the only
possibility that has been studied in this direction is warm inflation, which
uses "warm" (or "dissipative" if we consider more modest situation) direction
as the inflaton. In this talk we discuss other significant possibilities of
such directions which are dissipative and may or may not be "warm".
Affleck-Dine (AD) mechanism and other cosmological scenarios are discussed in
the light of "dissipative field", instead of using the conventional light field
with mass protection. We sometimes consider Morikawa-Sasaki coefficient for the
non-thermal background, which is important because the dissipation calculated
for a naive thermal background with $T\to 0$ is not enough to discuss the
dissipation with the non-thermal background.
| [
{
"created": "Mon, 11 Jan 2010 06:36:07 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Jan 2010 07:19:30 GMT",
"version": "v2"
},
{
"created": "Tue, 26 Jan 2010 09:18:02 GMT",
"version": "v3"
}
] | 2010-01-26 | [
[
"Matsuda",
"Tomohiro",
""
]
] | There are many flat directions in SUSY models, which may dissipate their energy and source the radiation background during inflation. However, the only possibility that has been studied in this direction is warm inflation, which uses "warm" (or "dissipative" if we consider more modest situation) direction as the inflaton. In this talk we discuss other significant possibilities of such directions which are dissipative and may or may not be "warm". Affleck-Dine (AD) mechanism and other cosmological scenarios are discussed in the light of "dissipative field", instead of using the conventional light field with mass protection. We sometimes consider Morikawa-Sasaki coefficient for the non-thermal background, which is important because the dissipation calculated for a naive thermal background with $T\to 0$ is not enough to discuss the dissipation with the non-thermal background. |
hep-ph/0508218 | Boris Blok | B. Blok and L. Frankfurt | On the behaviour of single scale hard small $x$ processes in QCD near
the black disc limit | 24 pages, 1 Figure. References added, and several misprints
eliminated | Phys.Rev.D73:054008,2006 | 10.1103/PhysRevD.73.054008 | null | hep-ph | null | We argue that at sufficiently small Bjorken $x$ where pQCD amplitude rapidly
increases with energy and violates probability conservation the shadowing
effects in the single-scale small $x$ hard QCD processes can be described by an
effective quantum field theory of interacting quasiparticles. The
quasiparticles are the perturbative QCD ladders. We find, within the WKB
approximation, that the smallness of the QCD coupling constant ensures the
hierarchy among many-quasiparticle interactions evaluated within physical
vacuum and in particular, the dominance in the Lagrangian of the triple
quasiparticle interaction. It is explained that the effective field theory
considered near the perturbative QCD vacuum contains a tachyon relevant for the
divergency of the perturbative QCD series at sufficiently small $x$. We solve
the equations of motion of the effective field theory within the WKB
approximation and find the physical vacuum and the transitions between the
false (perturbative) and physical vacua. Classical solutions which dominate
transitions between the false and physical vacua are kinks that cannot be
decomposed into perturbative series over the powers of $\alpha_s$. These kinks
lead to color inflation and the Bose-Einstein condensation of quasiparticles.
The account of the quantum fluctuations around the WKB solution reveals the
appearance of the "massless" particles-- "phonons". It is explained that
"phonons" are relevant for the black disc behaviour of small $x$ processes,
leading to a Froissart rise of the cross-section. The condensation of the
ladders produces a color network occupying a "macroscopic" longitudinal volume.
We discuss briefly the possible detection of new QCD effects.
| [
{
"created": "Fri, 19 Aug 2005 22:51:28 GMT",
"version": "v1"
},
{
"created": "Fri, 26 Aug 2005 11:50:55 GMT",
"version": "v2"
},
{
"created": "Wed, 16 Nov 2005 17:39:58 GMT",
"version": "v3"
},
{
"created": "Wed, 8 Mar 2006 15:50:45 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Blok",
"B.",
""
],
[
"Frankfurt",
"L.",
""
]
] | We argue that at sufficiently small Bjorken $x$ where pQCD amplitude rapidly increases with energy and violates probability conservation the shadowing effects in the single-scale small $x$ hard QCD processes can be described by an effective quantum field theory of interacting quasiparticles. The quasiparticles are the perturbative QCD ladders. We find, within the WKB approximation, that the smallness of the QCD coupling constant ensures the hierarchy among many-quasiparticle interactions evaluated within physical vacuum and in particular, the dominance in the Lagrangian of the triple quasiparticle interaction. It is explained that the effective field theory considered near the perturbative QCD vacuum contains a tachyon relevant for the divergency of the perturbative QCD series at sufficiently small $x$. We solve the equations of motion of the effective field theory within the WKB approximation and find the physical vacuum and the transitions between the false (perturbative) and physical vacua. Classical solutions which dominate transitions between the false and physical vacua are kinks that cannot be decomposed into perturbative series over the powers of $\alpha_s$. These kinks lead to color inflation and the Bose-Einstein condensation of quasiparticles. The account of the quantum fluctuations around the WKB solution reveals the appearance of the "massless" particles-- "phonons". It is explained that "phonons" are relevant for the black disc behaviour of small $x$ processes, leading to a Froissart rise of the cross-section. The condensation of the ladders produces a color network occupying a "macroscopic" longitudinal volume. We discuss briefly the possible detection of new QCD effects. |
2201.05509 | Albi Kerbizi | Xavier Artru and Albi Kerbizi | The String+${}^3P_0$ Model of Hadronization | 5 pages, 3 figures, Contribution to the 24th International Spin
Symposium (SPIN-2021) | null | 10.7566/JPSCP.37.020101 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the main theoretical aspects of the quantum mechanical
string+${}^3P_0$ model of polarized quark fragmentation for pseudoscalar and
vector meson production. The model is an extension of the Lund string
fragmentation model that systematically includes the quark spin degree of
freedom assuming the ${}^3P_0$ mechanism of quark pair production at string
breaking. The recently achieved introduction of vector mesons accounts for the
spin correlations between the latter and the quark of the fragmentation chain.
The string+${}^3P_0$ model reproduces transverse spin effects such as the
Collins effect and the dihadron asymmetry, and longitudinal spin effects such
as the jet handedness.
| [
{
"created": "Fri, 14 Jan 2022 15:28:19 GMT",
"version": "v1"
}
] | 2023-01-18 | [
[
"Artru",
"Xavier",
""
],
[
"Kerbizi",
"Albi",
""
]
] | We present the main theoretical aspects of the quantum mechanical string+${}^3P_0$ model of polarized quark fragmentation for pseudoscalar and vector meson production. The model is an extension of the Lund string fragmentation model that systematically includes the quark spin degree of freedom assuming the ${}^3P_0$ mechanism of quark pair production at string breaking. The recently achieved introduction of vector mesons accounts for the spin correlations between the latter and the quark of the fragmentation chain. The string+${}^3P_0$ model reproduces transverse spin effects such as the Collins effect and the dihadron asymmetry, and longitudinal spin effects such as the jet handedness. |
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