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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2307.14413 | Martin Hoferichter | Martin Hoferichter, Bastian Kubis, Marvin Zanke | Axial-vector transition form factors and $e^+ e^- \to f_1 \pi^+ \pi^-$ | 28 pages, 4 figures; journal version | JHEP 08 (2023) 209 | 10.1007/JHEP08(2023)209 | null | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the transition form factors (TFFs) of axial-vector mesons in the
context of currently available experimental data, including new constraints
from $e^+ e^- \to f_1(1285) \pi^+ \pi^-$ that imply stringent limits on the
high-energy behavior and, for the first time, allow us to provide an
unambiguous determination of the couplings corresponding to the two
antisymmetric TFFs. We discuss how these constraints can be implemented in a
vector-meson-dominance picture, and, in combination with contributions from the
light-cone expansion, construct TFFs as input for the evaluation of
axial-vector contributions to hadronic light-by-light scattering in the
anomalous magnetic moment of the muon.
| [
{
"created": "Wed, 26 Jul 2023 18:00:00 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Aug 2023 11:19:33 GMT",
"version": "v2"
}
] | 2023-08-31 | [
[
"Hoferichter",
"Martin",
""
],
[
"Kubis",
"Bastian",
""
],
[
"Zanke",
"Marvin",
""
]
] | We study the transition form factors (TFFs) of axial-vector mesons in the context of currently available experimental data, including new constraints from $e^+ e^- \to f_1(1285) \pi^+ \pi^-$ that imply stringent limits on the high-energy behavior and, for the first time, allow us to provide an unambiguous determination of the couplings corresponding to the two antisymmetric TFFs. We discuss how these constraints can be implemented in a vector-meson-dominance picture, and, in combination with contributions from the light-cone expansion, construct TFFs as input for the evaluation of axial-vector contributions to hadronic light-by-light scattering in the anomalous magnetic moment of the muon. |
2212.11242 | Sven Heinemeyer | F. Arco, S. Heinemeyer, M. M\"uhlleitner, K. Radchenko | Sensitivity to Triple Higgs Couplings via Di-Higgs Production in the
2HDM at the (HL-)LHC | 43 pages, 26 figures | null | null | DESY-22-203, IFT-UAM/CSIC-22-073, KA-TP-30-2022 | hep-ph | http://creativecommons.org/licenses/by-nc-sa/4.0/ | An important task of the LHC is the investigation of the Higgs-boson sector.
Of particular interest is the reconstruction of the Higgs potential, i.e. the
measurement of the Higgs self-couplings. Based on previous analyses, within the
2HDMs type~I and~II, we analyze several two-dimensional benchmark planes that
are over large parts in agreement with all theoretical and experimental
constraints. For these planes we evaluate di-Higgs production cross sections at
the (HL-)LHC with a center-of-mass energy of 13 TeV at NLO in the heavy
top-quark limit with the code HPAIR. We investige in particular the process $gg
\to hh$, with $h$ being the Higgs boson discovered at the LHC with a mass of
about 125 GeV. The top box diagram of the loop-mediated gluon fusion process
into Higgs pairs interferes with the $s$-channel exchange of the two CP-even
2HDM Higgs bosons $h$ and $H$ involving the trilinear couplings $\lambda_{hhh}$
and $\lambda_{hhH}$, respectively. Depending on the size of the involved
top-Yukawa and triple Higgs couplings as well as on the mass of $H$, the
contribution of the $s$-channel $H$~diagram can be dominating or be highly
suppressed. We find regions of the allowed parameter space in which the
di-Higgs production cross section can differ by many standard deviations from
its SM prediction, indicating possible access to deviations in $\lambda_{hhh}$
from the SM value $\lambda_{\rm SM}$ and/or contributions involving
$\lambda_{hhH}$. The sensitivity to $\lambda_{hhH}$ is further analyzed
employing the $m_{hh}$ distributions. We demonstrate how a possible measurement
of $\lambda_{hhH}$ depends on the various experimenal uncertainties. Depending
on the underlying parameter space, the HL-LHC may have the option not only to
detect beyond-the-Standard-Model triple Higgs couplings, but also to provide a
first rough measurement of their sizes.
| [
{
"created": "Wed, 21 Dec 2022 18:13:26 GMT",
"version": "v1"
}
] | 2022-12-22 | [
[
"Arco",
"F.",
""
],
[
"Heinemeyer",
"S.",
""
],
[
"Mühlleitner",
"M.",
""
],
[
"Radchenko",
"K.",
""
]
] | An important task of the LHC is the investigation of the Higgs-boson sector. Of particular interest is the reconstruction of the Higgs potential, i.e. the measurement of the Higgs self-couplings. Based on previous analyses, within the 2HDMs type~I and~II, we analyze several two-dimensional benchmark planes that are over large parts in agreement with all theoretical and experimental constraints. For these planes we evaluate di-Higgs production cross sections at the (HL-)LHC with a center-of-mass energy of 13 TeV at NLO in the heavy top-quark limit with the code HPAIR. We investige in particular the process $gg \to hh$, with $h$ being the Higgs boson discovered at the LHC with a mass of about 125 GeV. The top box diagram of the loop-mediated gluon fusion process into Higgs pairs interferes with the $s$-channel exchange of the two CP-even 2HDM Higgs bosons $h$ and $H$ involving the trilinear couplings $\lambda_{hhh}$ and $\lambda_{hhH}$, respectively. Depending on the size of the involved top-Yukawa and triple Higgs couplings as well as on the mass of $H$, the contribution of the $s$-channel $H$~diagram can be dominating or be highly suppressed. We find regions of the allowed parameter space in which the di-Higgs production cross section can differ by many standard deviations from its SM prediction, indicating possible access to deviations in $\lambda_{hhh}$ from the SM value $\lambda_{\rm SM}$ and/or contributions involving $\lambda_{hhH}$. The sensitivity to $\lambda_{hhH}$ is further analyzed employing the $m_{hh}$ distributions. We demonstrate how a possible measurement of $\lambda_{hhH}$ depends on the various experimenal uncertainties. Depending on the underlying parameter space, the HL-LHC may have the option not only to detect beyond-the-Standard-Model triple Higgs couplings, but also to provide a first rough measurement of their sizes. |
hep-ph/0604201 | Sheldon Stone | Radia Sia and Sheldon Stone | Model Independent Methods for Determining B(Y(5S)->Bs^{(*)}
anti-B}_s^{(*)})$ | Updated version #4 includes corrections that are documented in an
erratum to be published in PRD. (V3 is the published version.) Four pages, 2
figures. Four pages, 2 figures | Phys.Rev.D74:031501,2006; Erratum-ibid.D80:039901,2009 | 10.1103/PhysRevD.74.031501 10.1103/PhysRevD.80.039901 | SUHEP-06-2006 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We describe a method that provides a model independent measurement of the Bs
fraction in Y(5S) resonance decays, fs, using the relative rates of like-sign
versus opposite sign dileptons; the like-sign leptons result from B^0 and Bs
mixing. In addition, we show that determining the rates of single, double and
triple Ds mesons provides an alternative way of finding fs.
| [
{
"created": "Mon, 24 Apr 2006 14:34:34 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Jun 2006 12:55:41 GMT",
"version": "v2"
},
{
"created": "Mon, 21 Aug 2006 16:26:23 GMT",
"version": "v3"
},
{
"created": "Wed, 12 Aug 2009 20:09:48 GMT",
"version": "v4"
}
] | 2014-11-18 | [
[
"Sia",
"Radia",
""
],
[
"Stone",
"Sheldon",
""
]
] | We describe a method that provides a model independent measurement of the Bs fraction in Y(5S) resonance decays, fs, using the relative rates of like-sign versus opposite sign dileptons; the like-sign leptons result from B^0 and Bs mixing. In addition, we show that determining the rates of single, double and triple Ds mesons provides an alternative way of finding fs. |
0709.4461 | Carlos Merino | N. Armesto, C. Merino, G. Parente, and E. Zas | Charged Current Neutrino Cross Section and Tau Energy Loss at Ultra-High
Energies | 20 pages and 11 figures | Phys.Rev.D77:013001,2008 | 10.1103/PhysRevD.77.013001 | null | hep-ph | null | We evaluate both the tau lepton energy loss produced by photonuclear
interactions and the neutrino charged current cross section at ultra-high
energies, relevant to neutrino bounds with Earth-skimming tau neutrinos, using
different theoretical and phenomenological models for nucleon and nucleus
structure functions. The theoretical uncertainty is estimated by taking
different extrapolations of the structure function F2 to very low values of x,
in the low and moderate Q2 range for the tau lepton interaction and at high Q2
for the neutrino-nucleus inelastic cross section. It is at these extremely low
values of x where nuclear shadowing and parton saturation effects are unknown
and could be stronger than usually considered. For tau and neutrino energies
E=10^9 GeV we find uncertainties of a factor 4 for the tau energy loss and of a
factor 2 for the charged current neutrino-nucleus cross section.
| [
{
"created": "Thu, 27 Sep 2007 17:52:19 GMT",
"version": "v1"
},
{
"created": "Tue, 2 Oct 2007 10:02:13 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Armesto",
"N.",
""
],
[
"Merino",
"C.",
""
],
[
"Parente",
"G.",
""
],
[
"Zas",
"E.",
""
]
] | We evaluate both the tau lepton energy loss produced by photonuclear interactions and the neutrino charged current cross section at ultra-high energies, relevant to neutrino bounds with Earth-skimming tau neutrinos, using different theoretical and phenomenological models for nucleon and nucleus structure functions. The theoretical uncertainty is estimated by taking different extrapolations of the structure function F2 to very low values of x, in the low and moderate Q2 range for the tau lepton interaction and at high Q2 for the neutrino-nucleus inelastic cross section. It is at these extremely low values of x where nuclear shadowing and parton saturation effects are unknown and could be stronger than usually considered. For tau and neutrino energies E=10^9 GeV we find uncertainties of a factor 4 for the tau energy loss and of a factor 2 for the charged current neutrino-nucleus cross section. |
hep-ph/9308340 | null | G. Azuelos and A. Djouadi | New Fermions at e$^+$e$^-$ Colliders: II.~Signals and Backgrounds | 22 pages + 9 figures (not included: available by mail from A.
Djouadi), Preprint UdeM-LPN-TH-93-158 | Z. Phys. C63 (1994) 327-338 | 10.1007/BF01411025 | null | hep-ph | null | We discuss the production, at high--energy e$^+$e$^-$ linear colliders, of
new heavy fermions predicted by extensions of the Standard Model. We analyze in
great details the various signals and the corresponding backgrounds for both
pair production and single production in association with ordinary fermions.
Concentrating on new leptons, we use a model detector for e$^+$e$^-$ collisions
at a center of mass energy of 500 GeV, to illustrate the discovery potential of
the Next Linear Colliders.
| [
{
"created": "Wed, 25 Aug 1993 20:21:46 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Azuelos",
"G.",
""
],
[
"Djouadi",
"A.",
""
]
] | We discuss the production, at high--energy e$^+$e$^-$ linear colliders, of new heavy fermions predicted by extensions of the Standard Model. We analyze in great details the various signals and the corresponding backgrounds for both pair production and single production in association with ordinary fermions. Concentrating on new leptons, we use a model detector for e$^+$e$^-$ collisions at a center of mass energy of 500 GeV, to illustrate the discovery potential of the Next Linear Colliders. |
hep-ph/0301154 | Chuan Hung Chen | Chuan-Hung Chen | What can we learn from $B^{+}\to D^{(*)-}_{s} K^{+} \pi^{+}$, $B_{d}\to
D_{s}^{(*)-} K^{0} \pi^{+}$ and $B_{d}\to D_{s}^{(*)-} K^{*+}$ decays? | 14 pages, 4 figures, Revtex4, version to appear in PLB | Phys.Lett. B560 (2003) 178-187 | 10.1016/S0370-2693(03)00398-8 | null | hep-ph hep-ex | null | We study the nonresonant three-body decays of $B^{+}\to D^{(*)-}_{s} K^{+}
\pi^{+}$ and $B_{d}\to D_{s}^{(*)-} K^{0} \pi^{+}$. We find that these decays
can provide the information on the time-like form factors of $D^{(*)}_{s} K$.
We also explicitly investigate $B_{d}\to D_{s}^{(*)-} K^{*+}$ decays by
discriminating the nonresonant contributions with the unknown $D^{(*)}_{s}$
wave functions being fixed by the measured mode of $B_{d}\to D_{s}^{-} K^{+}$.
| [
{
"created": "Mon, 20 Jan 2003 04:05:25 GMT",
"version": "v1"
},
{
"created": "Wed, 29 Jan 2003 08:14:01 GMT",
"version": "v2"
},
{
"created": "Mon, 17 Mar 2003 09:36:34 GMT",
"version": "v3"
}
] | 2009-11-10 | [
[
"Chen",
"Chuan-Hung",
""
]
] | We study the nonresonant three-body decays of $B^{+}\to D^{(*)-}_{s} K^{+} \pi^{+}$ and $B_{d}\to D_{s}^{(*)-} K^{0} \pi^{+}$. We find that these decays can provide the information on the time-like form factors of $D^{(*)}_{s} K$. We also explicitly investigate $B_{d}\to D_{s}^{(*)-} K^{*+}$ decays by discriminating the nonresonant contributions with the unknown $D^{(*)}_{s}$ wave functions being fixed by the measured mode of $B_{d}\to D_{s}^{-} K^{+}$. |
hep-ph/0412374 | Xiao-Gang He | Xiao-Gang He, Xue-Qian Li, Bruce H. J. McKellar, and Yue Zhang | Berry Phase in Neutrino Oscillations | RevTex 16 pages, no figures, new discussions about sterile neutrino
added,typos corrected and errors in references corrected | Phys.Rev. D72 (2005) 053012 | 10.1103/PhysRevD.72.053012 | null | hep-ph astro-ph hep-ex hep-th quant-ph | null | We study the Berry phase in neutrino oscillations for both Dirac and Majorana
neutrinos. In order to have a Berry phase, the neutrino oscillations must occur
in a varying medium, the neutrino-background interactions must depend on at
least two independent densities, and also there must be CP violation if the
neutrino interactions with matter are mediated only by the standard model W and
Z boson exchanges which implies that there must be at least three generations
of neutrinos. The CP violating Majorana phases do not play a role in generating
a Berry phase. We show that a natural way to satisfy the conditions for the
generation of a Berry phase is to have sterile neutrinos with active-sterile
neutrino mixing, in which case at least two active and one sterile neutrinos
are required. If there are additional new CP violating flavor changing
interactions, it is also possible to have a non-zero Berry phase with just two
generations.
| [
{
"created": "Fri, 24 Dec 2004 03:26:23 GMT",
"version": "v1"
},
{
"created": "Sun, 2 Jan 2005 19:04:17 GMT",
"version": "v2"
},
{
"created": "Fri, 7 Jan 2005 02:42:13 GMT",
"version": "v3"
},
{
"created": "Wed, 18 May 2005 04:16:32 GMT",
"version": "v4"
}
] | 2009-11-10 | [
[
"He",
"Xiao-Gang",
""
],
[
"Li",
"Xue-Qian",
""
],
[
"McKellar",
"Bruce H. J.",
""
],
[
"Zhang",
"Yue",
""
]
] | We study the Berry phase in neutrino oscillations for both Dirac and Majorana neutrinos. In order to have a Berry phase, the neutrino oscillations must occur in a varying medium, the neutrino-background interactions must depend on at least two independent densities, and also there must be CP violation if the neutrino interactions with matter are mediated only by the standard model W and Z boson exchanges which implies that there must be at least three generations of neutrinos. The CP violating Majorana phases do not play a role in generating a Berry phase. We show that a natural way to satisfy the conditions for the generation of a Berry phase is to have sterile neutrinos with active-sterile neutrino mixing, in which case at least two active and one sterile neutrinos are required. If there are additional new CP violating flavor changing interactions, it is also possible to have a non-zero Berry phase with just two generations. |
2108.03240 | Dave Sutherland | Timothy Cohen, Nathaniel Craig, Xiaochuan Lu, Dave Sutherland | Unitarity Violation and the Geometry of Higgs EFTs | 42+12 pages, 6 figures. v2: Added references. v3: Journal version | null | 10.1007/JHEP12(2021)003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the scale of unitarity violation from the geometry of Effective
Field Theory (EFT) extensions of the Standard Model Higgs sector. The
high-energy behavior of amplitudes with more than four scalar legs depends on
derivatives of geometric invariants with respect to the physical Higgs field
$h$, such that higher-point amplitudes begin to reconstruct the scalar manifold
away from our vacuum. In theories whose low-energy limit can be described by
the Higgs EFT (HEFT) but not the Standard Model EFT (SMEFT), non-analyticities
in the vicinity of our vacuum limit the radius of convergence of geometric
invariants, leading to unitarity violation at energies below $4\pi v$. Our
results unify approaches to the HEFT/SMEFT dichotomy based on unitarity,
analyticity, and geometry, and more broadly illustrate the sense in which
observables probe the geometry of an EFT. Along the way, we provide novel
basis-independent results for Goldstone/Higgs boson scattering amplitudes
expressed in terms of geometric covariant quantities.
| [
{
"created": "Fri, 6 Aug 2021 18:00:00 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Aug 2021 14:41:41 GMT",
"version": "v2"
},
{
"created": "Wed, 1 Dec 2021 16:36:52 GMT",
"version": "v3"
}
] | 2021-12-22 | [
[
"Cohen",
"Timothy",
""
],
[
"Craig",
"Nathaniel",
""
],
[
"Lu",
"Xiaochuan",
""
],
[
"Sutherland",
"Dave",
""
]
] | We derive the scale of unitarity violation from the geometry of Effective Field Theory (EFT) extensions of the Standard Model Higgs sector. The high-energy behavior of amplitudes with more than four scalar legs depends on derivatives of geometric invariants with respect to the physical Higgs field $h$, such that higher-point amplitudes begin to reconstruct the scalar manifold away from our vacuum. In theories whose low-energy limit can be described by the Higgs EFT (HEFT) but not the Standard Model EFT (SMEFT), non-analyticities in the vicinity of our vacuum limit the radius of convergence of geometric invariants, leading to unitarity violation at energies below $4\pi v$. Our results unify approaches to the HEFT/SMEFT dichotomy based on unitarity, analyticity, and geometry, and more broadly illustrate the sense in which observables probe the geometry of an EFT. Along the way, we provide novel basis-independent results for Goldstone/Higgs boson scattering amplitudes expressed in terms of geometric covariant quantities. |
hep-ph/0601184 | N. Nikolaev | N.N. Nikolaev (Forshcungszentrum Juelich and Landau Institute) and
F.F. Pavlov (Forshcungszentrum Juelich) | Polarization Buildup of Stored Protons and Antiprotons: Filtex Result
and Implications for Pax at Fair | 11 pages, Plenary talk at 11th International Workshop On High Energy
Spin Physics (DUBNA-SPIN-05) 27 Sep - 1 Oct 2005, Dubna, Russia, typos
corrected | null | null | FZJ-IKP-TH-2005-45 | hep-ph | null | The spin filtering by a multiple passage of a stored beam through a polarized
internal gas target is a unique possibility of polarizing high luminosity beam
of antiprotons to a high degree of polarization. Apart from the polarization by
the spin-dependent transmission, a unique geometrical feature of spin filtering
in storage rings is a scattering of stored particles within the ring
\cite{Meyer}. A rotation of the spin in the scattering process affects the
polarization buildup. We report here a fully quantum-mechanical evolution
equation for the spin-density matrix of a stored beam which incorporates the
scattering within the ring. We show how dramatically the interplay of the
transmission and scattering within the ring changes from polarized electrons to
polarized protons in the atomic target. After discussions of the FILTEX results
on filtering of stored protons \cite{FILTEX}, we comment on the strategy of
spin filtering of antiprotons for the PAX experiment at GSI FAIR \cite{PAX-TP}.
| [
{
"created": "Sun, 22 Jan 2006 15:48:56 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Jun 2006 11:47:03 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Nikolaev",
"N. N.",
"",
"Forshcungszentrum Juelich and Landau Institute"
],
[
"Pavlov",
"F. F.",
"",
"Forshcungszentrum Juelich"
]
] | The spin filtering by a multiple passage of a stored beam through a polarized internal gas target is a unique possibility of polarizing high luminosity beam of antiprotons to a high degree of polarization. Apart from the polarization by the spin-dependent transmission, a unique geometrical feature of spin filtering in storage rings is a scattering of stored particles within the ring \cite{Meyer}. A rotation of the spin in the scattering process affects the polarization buildup. We report here a fully quantum-mechanical evolution equation for the spin-density matrix of a stored beam which incorporates the scattering within the ring. We show how dramatically the interplay of the transmission and scattering within the ring changes from polarized electrons to polarized protons in the atomic target. After discussions of the FILTEX results on filtering of stored protons \cite{FILTEX}, we comment on the strategy of spin filtering of antiprotons for the PAX experiment at GSI FAIR \cite{PAX-TP}. |
2211.09065 | Girish Kumar | Diganta Das, Jaydeb Das, Girish Kumar and Niladribihari Sahoo | $\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^-$ as probe of
CP-violating New Physics | 28 pages, 4 captioned figures; updated NP benchmarks following the
latest RK(*) measurements; matches journal version | Phys.Rev.D 108 (2023) 1, 015001 | 10.1103/PhysRevD.108.015001 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We investigate the possible sizes of all the CP-violating asymmetries offered
by the angular distribution of rare decay $\Lambda_b\rightarrow \Lambda(\to p
\pi^-) \ell^+\ell^-$ in the Standard Model and new physics scenarios motivated
by the recent $b\to s \ell^+\ell^-$ anomalies. We work in a model-independent
effective theory framework and discuss the sensitivity of CP asymmetries to new
${O}_{9,10}$ operators and their chirality flipped counterparts. We find that
the size of many of the CP asymmetries can be at the level of a few percent in
new physics scenarios consistent with current $b\to s\ell^+\ell^-$ data at a
level of $1\sigma$. We emphasize that measurements of these CP asymmetries can
be used to discriminate different new physics scenarios in $b\to s
\ell^+\ell^-$.
| [
{
"created": "Wed, 16 Nov 2022 17:28:55 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Nov 2022 10:17:38 GMT",
"version": "v2"
},
{
"created": "Thu, 20 Jul 2023 11:21:33 GMT",
"version": "v3"
}
] | 2023-07-21 | [
[
"Das",
"Diganta",
""
],
[
"Das",
"Jaydeb",
""
],
[
"Kumar",
"Girish",
""
],
[
"Sahoo",
"Niladribihari",
""
]
] | We investigate the possible sizes of all the CP-violating asymmetries offered by the angular distribution of rare decay $\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^-$ in the Standard Model and new physics scenarios motivated by the recent $b\to s \ell^+\ell^-$ anomalies. We work in a model-independent effective theory framework and discuss the sensitivity of CP asymmetries to new ${O}_{9,10}$ operators and their chirality flipped counterparts. We find that the size of many of the CP asymmetries can be at the level of a few percent in new physics scenarios consistent with current $b\to s\ell^+\ell^-$ data at a level of $1\sigma$. We emphasize that measurements of these CP asymmetries can be used to discriminate different new physics scenarios in $b\to s \ell^+\ell^-$. |
2111.02713 | Keisho Hidaka | Keisho Hidaka (1), Helmut Eberl (2), Elena Ginina (2) ((1) Tokyo
Gakugei U., (2) HEPHY, Vienna) | The h(125) decays to c cbar, b bbar, b sbar, photon photon and gluon
gluon in the light of the MSSM with quark flavor violation | 6 pages, 3 figures, Contribution to the proceedings of the European
Physical Society Conference on High Energy Physics (EPS-HEP2021), 26-30 July
2021 | PoS EPS-HEP2021 (2022) 594 | null | HEPHY-PUB 1029/21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Higgs boson decays $h^0 \to c \bar{c}, b \bar{b}, b \bar{s},
\gamma \gamma, g g$ in the Minimal Supersymmetric Standard Model (MSSM) with
general quark flavor violation (QFV), identifying the $h^0$ as the Higgs boson
with a mass of 125 GeV. We compute the widths of the $h^0$ decays to $c \bar c,
b \bar b, b \bar s (s \bar b)$ at full one-loop level. For the $h^0$ decays to
photon photon and gluon gluon we compute the widths at NLO QCD level. We
perform a systematic MSSM parameter scan respecting all the relevant
constraints, i.e. theoretical constraints from vacuum stability conditions and
experimental constraints, such as those from K- and B-meson data and
electroweak precision data, as well as recent limits on Supersymmetric (SUSY)
particle masses and the 125 GeV Higgs boson data from LHC experiments. From the
parameter scan, we find that the deviations of these MSSM widths from the
Standard Model (SM) values can be quite sizable. All of these large deviations
in the $h^0$ decays are due to large scharm-stop mixing, large scharm/stop
involved trilinear couplings $T_{U23}, T_{U32}, T_{U33}$, large
sstrange-sbottom mixing, and large sstrange/sbottom involved trilinear
couplings $T_{D23}, T_{D32}, T_{D33}$. International Linear Collider (ILC) can
observe such large deviations from the SM at high signal significance. In case
the deviation pattern shown here is really observed at ILC, then it would
strongly suggest the discovery of QFV SUSY (the MSSM with QFV).
| [
{
"created": "Thu, 4 Nov 2021 09:50:11 GMT",
"version": "v1"
}
] | 2022-08-10 | [
[
"Hidaka",
"Keisho",
""
],
[
"Eberl",
"Helmut",
""
],
[
"Ginina",
"Elena",
""
]
] | We study the Higgs boson decays $h^0 \to c \bar{c}, b \bar{b}, b \bar{s}, \gamma \gamma, g g$ in the Minimal Supersymmetric Standard Model (MSSM) with general quark flavor violation (QFV), identifying the $h^0$ as the Higgs boson with a mass of 125 GeV. We compute the widths of the $h^0$ decays to $c \bar c, b \bar b, b \bar s (s \bar b)$ at full one-loop level. For the $h^0$ decays to photon photon and gluon gluon we compute the widths at NLO QCD level. We perform a systematic MSSM parameter scan respecting all the relevant constraints, i.e. theoretical constraints from vacuum stability conditions and experimental constraints, such as those from K- and B-meson data and electroweak precision data, as well as recent limits on Supersymmetric (SUSY) particle masses and the 125 GeV Higgs boson data from LHC experiments. From the parameter scan, we find that the deviations of these MSSM widths from the Standard Model (SM) values can be quite sizable. All of these large deviations in the $h^0$ decays are due to large scharm-stop mixing, large scharm/stop involved trilinear couplings $T_{U23}, T_{U32}, T_{U33}$, large sstrange-sbottom mixing, and large sstrange/sbottom involved trilinear couplings $T_{D23}, T_{D32}, T_{D33}$. International Linear Collider (ILC) can observe such large deviations from the SM at high signal significance. In case the deviation pattern shown here is really observed at ILC, then it would strongly suggest the discovery of QFV SUSY (the MSSM with QFV). |
hep-ph/0309271 | Takumi Doi | Jun Sugiyama, Takumi Doi and Makoto Oka (Tokyo Inst. Tech) | Penta-quark baryon from the QCD Sum Rule | 7 pages, 3 figures, To be published in Phys.Lett.B | Phys.Lett. B581 (2004) 167-174 | 10.1016/j.physletb.2003.12.018 | null | hep-ph hep-ex nucl-th | null | Exotic penta-quark baryon with strangeness +1, \Theta^+, is studied in the
QCD sum rule approach. We derive sum rules for the positive and negative parity
baryon states with J=1/2 and I=0. It is found that the standard values of the
QCD condensates predict a negative parity \Theta^+ of mass \simeq 1.5 GeV,
while no positive parity state is found. We stress the roles of chiral-odd
condensates in determining the parity and mass of \Theta^+.
| [
{
"created": "Wed, 24 Sep 2003 10:19:53 GMT",
"version": "v1"
},
{
"created": "Tue, 9 Dec 2003 03:59:58 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Sugiyama",
"Jun",
"",
"Tokyo Inst. Tech"
],
[
"Doi",
"Takumi",
"",
"Tokyo Inst. Tech"
],
[
"Oka",
"Makoto",
"",
"Tokyo Inst. Tech"
]
] | Exotic penta-quark baryon with strangeness +1, \Theta^+, is studied in the QCD sum rule approach. We derive sum rules for the positive and negative parity baryon states with J=1/2 and I=0. It is found that the standard values of the QCD condensates predict a negative parity \Theta^+ of mass \simeq 1.5 GeV, while no positive parity state is found. We stress the roles of chiral-odd condensates in determining the parity and mass of \Theta^+. |
1305.0017 | Michael Trott | Elizabeth E. Jenkins, Aneesh V. Manohar and Michael Trott | On Gauge Invariance and Minimal Coupling | 25 pp, 2 figures v2: refs added, JHEP version, conclusions unchanged | JHEP 1309 (2013) 063 | 10.1007/JHEP09(2013)063 | CERN-PH-TH-160 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The principle of minimal coupling has been used in the study of Higgs boson
interactions to argue that certain higher dimensional operators in the
low-energy effective theory generalization of the Standard Model are suppressed
by loop factors, and thus smaller than others. It also has been extensively
used to analyze beyond-the-standard-model theories. We show that in field
theory, and even in quantum mechanics, the concept of minimal coupling is
ill-defined and inapplicable as a general principle, and give many pedagogical
examples which illustrate this fact. We also clarify some related
misconceptions about the dynamics of strongly coupled gauge theories. Many
arguments in the literature on Higgs boson interactions that use minimal
coupling, particularly in pseudo-Goldstone Higgs theories, are inherently
flawed.
| [
{
"created": "Tue, 30 Apr 2013 20:14:35 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Sep 2013 10:54:41 GMT",
"version": "v2"
}
] | 2015-06-15 | [
[
"Jenkins",
"Elizabeth E.",
""
],
[
"Manohar",
"Aneesh V.",
""
],
[
"Trott",
"Michael",
""
]
] | The principle of minimal coupling has been used in the study of Higgs boson interactions to argue that certain higher dimensional operators in the low-energy effective theory generalization of the Standard Model are suppressed by loop factors, and thus smaller than others. It also has been extensively used to analyze beyond-the-standard-model theories. We show that in field theory, and even in quantum mechanics, the concept of minimal coupling is ill-defined and inapplicable as a general principle, and give many pedagogical examples which illustrate this fact. We also clarify some related misconceptions about the dynamics of strongly coupled gauge theories. Many arguments in the literature on Higgs boson interactions that use minimal coupling, particularly in pseudo-Goldstone Higgs theories, are inherently flawed. |
hep-ph/0512304 | Eduardo Pont\'on | Eduardo Ponton and Lin Wang | Radiative Effects on the Chiral Square | 70 pages, 15 figures | JHEP 0611 (2006) 018 | 10.1088/1126-6708/2006/11/018 | null | hep-ph hep-th | null | We consider general field theories in six dimensions, with two of the
dimensions compactified on a T_{2}/Z_{4} orbifold. Six-dimensional Weyl
fermions propagating on this background give rise to a chiral zero-mode, which
makes them interesting for phenomenological applications. The compact
two-dimensional space is flat and has three conical singularities. We consider
the one-loop structure of these theories, and show that the presence of
logarithmic divergences requires the introduction of counterterms precisely at
these three singular points. We also show that the corresponding localized
operators are rotationally symmetric in the plane of the two extra dimensions,
as expected from the geometry about the singularities. We derive the
propagators for spin-0, spin-1/2 and spin-1 fields in momentum space, in such a
way that the appropriate boundary conditions are satisfied. This allows us to
efficiently calculate loop diagrams in any given model. We give general
expressions for the mass splittings among Kaluza-Klein modes within a given
level. Our results can also be used to obtain interesting KK-parity preserving
interactions among Kaluza-Klein modes. We pay special attention to the
components of six-dimensional gauge fields that transform as scalars under the
four-dimensional Lorentz group. These states provide a characteristic signature
for these scenarios. In particular, we find that they can easily be the
lightest particles in the Kaluza-Klein spectrum.
| [
{
"created": "Thu, 22 Dec 2005 18:08:56 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Ponton",
"Eduardo",
""
],
[
"Wang",
"Lin",
""
]
] | We consider general field theories in six dimensions, with two of the dimensions compactified on a T_{2}/Z_{4} orbifold. Six-dimensional Weyl fermions propagating on this background give rise to a chiral zero-mode, which makes them interesting for phenomenological applications. The compact two-dimensional space is flat and has three conical singularities. We consider the one-loop structure of these theories, and show that the presence of logarithmic divergences requires the introduction of counterterms precisely at these three singular points. We also show that the corresponding localized operators are rotationally symmetric in the plane of the two extra dimensions, as expected from the geometry about the singularities. We derive the propagators for spin-0, spin-1/2 and spin-1 fields in momentum space, in such a way that the appropriate boundary conditions are satisfied. This allows us to efficiently calculate loop diagrams in any given model. We give general expressions for the mass splittings among Kaluza-Klein modes within a given level. Our results can also be used to obtain interesting KK-parity preserving interactions among Kaluza-Klein modes. We pay special attention to the components of six-dimensional gauge fields that transform as scalars under the four-dimensional Lorentz group. These states provide a characteristic signature for these scenarios. In particular, we find that they can easily be the lightest particles in the Kaluza-Klein spectrum. |
2012.09298 | Scott A. Yost | Scott A. Yost, Matthew Dittrich, Stanislaw Jadach, B.F.L. Ward,
Zbigniew W\k{a}s | KKMC-hh for Precision Electroweak Phenomenology at the LHC | 6 pages, 8 figures. Presented by S.A. Yost at ICHEP2020, Prague
(virtual conference). Version 2 has minor wording changes | PoS(ICHEP2020)349 | null | BU-HEPP-20-08 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We describe the program KKMC-hh, which calculates Z boson processes in
hadronic collisions using coherent exclusive exponentiation (CEEX) with exact
second-order photonic corrections at next-to-leading log and first-order weak
vertex corrections, including initial and final state photonic radiation and
initial-final interference. We describe current applications to precision
forward-backward asymmetry calculations for the measurement of the electroweak
mixing angle at the LHC.
| [
{
"created": "Wed, 16 Dec 2020 22:31:15 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Dec 2020 15:23:16 GMT",
"version": "v2"
}
] | 2021-01-27 | [
[
"Yost",
"Scott A.",
""
],
[
"Dittrich",
"Matthew",
""
],
[
"Jadach",
"Stanislaw",
""
],
[
"Ward",
"B. F. L.",
""
],
[
"Wąs",
"Zbigniew",
""
]
] | We describe the program KKMC-hh, which calculates Z boson processes in hadronic collisions using coherent exclusive exponentiation (CEEX) with exact second-order photonic corrections at next-to-leading log and first-order weak vertex corrections, including initial and final state photonic radiation and initial-final interference. We describe current applications to precision forward-backward asymmetry calculations for the measurement of the electroweak mixing angle at the LHC. |
1810.10776 | Jong-Hyun Yoon | Sunghyun Kang, Stefano Scopel, Gaurav Tomar, Jong-Hyun Yoon | Effective models of WIMP Direct Detection in DAMA/LIBRA-phase2 | 4 pages, 2 figures, Contribution to the Proceedings of the 39th
International Conference on High Energy Physics, ICHEP 2018, Seoul, Korea | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Since the DAMA/LIBRA collaboration released updated results from their search
for the annual modulation signal expected from Dark Matter (DM) scattering in
their NaI detectors, we have fitted the updated DAMA result for the modulation
amplitudes for a Weakly Interacting Massive Particle (WIMP) signal,
parameterizing the interaction with nuclei in terms of the most general
effective Lagrangian for a WIMP particle spin 1/2, systematically assuming
dominance of one of the 14 possible interaction terms and a standard Maxwellian
for the WIMP velocity distribution. We find that most of the couplings of the
non-relativistic effective Hamiltonian can provide a better fit compared to the
standard Spin Independent interaction case, and with a reduced fine-tuning of
the three parameters (WIMP mass, WIMP-nucleon effective cross-section and ratio
between the WIMP-neutron and the WIMP-proton couplings). In addition, effective
models for which the cross section depends explicitly on the WIMP incoming
velocity can provide a better fit of the DAMA data at large values of
$m_{\chi}$ compared to the standard velocity-independent cross-section due to a
different phase of the modulation amplitudes. All the best fit solutions are in
tension with exclusion plots of both XENON1T and PICO60.
| [
{
"created": "Thu, 25 Oct 2018 08:48:45 GMT",
"version": "v1"
}
] | 2018-10-26 | [
[
"Kang",
"Sunghyun",
""
],
[
"Scopel",
"Stefano",
""
],
[
"Tomar",
"Gaurav",
""
],
[
"Yoon",
"Jong-Hyun",
""
]
] | Since the DAMA/LIBRA collaboration released updated results from their search for the annual modulation signal expected from Dark Matter (DM) scattering in their NaI detectors, we have fitted the updated DAMA result for the modulation amplitudes for a Weakly Interacting Massive Particle (WIMP) signal, parameterizing the interaction with nuclei in terms of the most general effective Lagrangian for a WIMP particle spin 1/2, systematically assuming dominance of one of the 14 possible interaction terms and a standard Maxwellian for the WIMP velocity distribution. We find that most of the couplings of the non-relativistic effective Hamiltonian can provide a better fit compared to the standard Spin Independent interaction case, and with a reduced fine-tuning of the three parameters (WIMP mass, WIMP-nucleon effective cross-section and ratio between the WIMP-neutron and the WIMP-proton couplings). In addition, effective models for which the cross section depends explicitly on the WIMP incoming velocity can provide a better fit of the DAMA data at large values of $m_{\chi}$ compared to the standard velocity-independent cross-section due to a different phase of the modulation amplitudes. All the best fit solutions are in tension with exclusion plots of both XENON1T and PICO60. |
1711.02272 | Gaoli Chen | Gaoli Chen | Clebsch-Gordan coefficients of discrete groups in subgroup bases | 14+24 pages, update introduction, journal reference, and DOI | Int. J. Mod. Phys. A, 33, 1850055 (2018) | 10.1142/S0217751X18500550 | null | hep-ph hep-th math-ph math.MP | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We express each Clebsch-Gordan (CG) coefficient of a discrete group as a
product of a CG coefficient of its subgroup and a factor, which we call an
embedding factor. With an appropriate definition, such factors are fixed up to
phase ambiguities. Particularly, they are invariant under basis transformations
of irreducible representations of both the group and its subgroup. We then
impose on the embedding factors constraints, which relate them to their
counterparts under complex conjugate and therefore restrict the phases of
embedding factors. In some cases, the phase ambiguities are reduced to sign
ambiguities. We describe the procedure of obtaining embedding factors and then
calculate CG coefficients of the group \mathcal{PSL}_{2}\left(7\right) in terms
of embedding factors of its subgroups S_{4} and \mathcal{T}_{7}.
| [
{
"created": "Tue, 7 Nov 2017 03:41:35 GMT",
"version": "v1"
},
{
"created": "Sun, 22 Apr 2018 16:01:50 GMT",
"version": "v2"
}
] | 2018-04-24 | [
[
"Chen",
"Gaoli",
""
]
] | We express each Clebsch-Gordan (CG) coefficient of a discrete group as a product of a CG coefficient of its subgroup and a factor, which we call an embedding factor. With an appropriate definition, such factors are fixed up to phase ambiguities. Particularly, they are invariant under basis transformations of irreducible representations of both the group and its subgroup. We then impose on the embedding factors constraints, which relate them to their counterparts under complex conjugate and therefore restrict the phases of embedding factors. In some cases, the phase ambiguities are reduced to sign ambiguities. We describe the procedure of obtaining embedding factors and then calculate CG coefficients of the group \mathcal{PSL}_{2}\left(7\right) in terms of embedding factors of its subgroups S_{4} and \mathcal{T}_{7}. |
1710.10617 | Arindam Chatterjee | Arindam Chatterjee, Juhi Dutta, Santosh Kumar Rai | Natural SUSY at LHC with Right-Sneutrino LSP | matches published version | null | 10.1007/JHEP06(2018)042 | HRI-RECAPP-2017-13 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study an extension of the minimal supersymmetric standard model (MSSM)
with additional right-handed singlet neutrino superfields. While such an
extension incorporates a mechanism for the neutrino mass, it also opens up the
possibility of having the right-sneutrinos ($\widetilde{\nu}$) as the lightest
supersymmetric particle (LSP). In this work, we focus on the the viability of
rather small ($\lesssim 500$ GeV) higgsino mass parameter ($\mu$), an important
ingredient for "naturalness", in the presence of such a LSP. For simplicity, we
assume that the bino and wino mass parameters are much heavier, thus we only
consider (almost) pure and compressed higgsino-like states, with small
$\mathcal{O}(10^{-2})$ gaugino admixture. Considering only prompt decays of the
higgino-like states, especially the lightest chargino, we discuss the
importance of leptonic channels consisting of up to two leptons with large
missing transverse energy to probe this scenario at the Large Hadron Collider
(LHC). Further, we emphasize on how the gaugino mass parameters, although very
heavy, affects the decay of the low-lying higgsino-like states, thus
significantly affecting the proposed signatures at LHC.
| [
{
"created": "Sun, 29 Oct 2017 13:52:19 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Jul 2018 07:46:17 GMT",
"version": "v2"
}
] | 2018-07-20 | [
[
"Chatterjee",
"Arindam",
""
],
[
"Dutta",
"Juhi",
""
],
[
"Rai",
"Santosh Kumar",
""
]
] | We study an extension of the minimal supersymmetric standard model (MSSM) with additional right-handed singlet neutrino superfields. While such an extension incorporates a mechanism for the neutrino mass, it also opens up the possibility of having the right-sneutrinos ($\widetilde{\nu}$) as the lightest supersymmetric particle (LSP). In this work, we focus on the the viability of rather small ($\lesssim 500$ GeV) higgsino mass parameter ($\mu$), an important ingredient for "naturalness", in the presence of such a LSP. For simplicity, we assume that the bino and wino mass parameters are much heavier, thus we only consider (almost) pure and compressed higgsino-like states, with small $\mathcal{O}(10^{-2})$ gaugino admixture. Considering only prompt decays of the higgino-like states, especially the lightest chargino, we discuss the importance of leptonic channels consisting of up to two leptons with large missing transverse energy to probe this scenario at the Large Hadron Collider (LHC). Further, we emphasize on how the gaugino mass parameters, although very heavy, affects the decay of the low-lying higgsino-like states, thus significantly affecting the proposed signatures at LHC. |
2008.04430 | Ke-Pan Xie | Jeong-Pyong Hong, Sunghoon Jung and Ke-Pan Xie | Fermi-ball dark matter from a first-order phase transition | 11 pages, 5 figures. Accepted version for PRD | Phys. Rev. D 102, 075028 (2020) | 10.1103/PhysRevD.102.075028 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel dark matter (DM) scenario based on a first-order phase
transition in the early universe. If dark fermions acquire a huge mass gap
between true and false vacua, they can barely penetrate into the new phase.
Instead, they get trapped in the old phase and accumulate to form macroscopic
objects, dubbed Fermi-balls. We show that Fermi-balls can explain the DM
abundance in a wide range of models and parameter space, depending most
crucially on the dark-fermion asymmetry and the phase transition energy scale
(possible up to the Planck scale). They are stable by the balance between
fermion's quantum pressure against free energy release, hence turn out to be
macroscopic in mass and size. However, this scenario generally produces no
detectable signals (which may explain the null results of DM searches), except
for detectable gravitational waves (GWs) for electroweak scale phase
transitions; although the detection of such stochastic GWs does not necessarily
imply a Fermi-ball DM scenario.
| [
{
"created": "Mon, 10 Aug 2020 21:54:08 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Oct 2020 06:47:11 GMT",
"version": "v2"
}
] | 2020-10-28 | [
[
"Hong",
"Jeong-Pyong",
""
],
[
"Jung",
"Sunghoon",
""
],
[
"Xie",
"Ke-Pan",
""
]
] | We propose a novel dark matter (DM) scenario based on a first-order phase transition in the early universe. If dark fermions acquire a huge mass gap between true and false vacua, they can barely penetrate into the new phase. Instead, they get trapped in the old phase and accumulate to form macroscopic objects, dubbed Fermi-balls. We show that Fermi-balls can explain the DM abundance in a wide range of models and parameter space, depending most crucially on the dark-fermion asymmetry and the phase transition energy scale (possible up to the Planck scale). They are stable by the balance between fermion's quantum pressure against free energy release, hence turn out to be macroscopic in mass and size. However, this scenario generally produces no detectable signals (which may explain the null results of DM searches), except for detectable gravitational waves (GWs) for electroweak scale phase transitions; although the detection of such stochastic GWs does not necessarily imply a Fermi-ball DM scenario. |
hep-ph/9406278 | Steve Godfrey | Stephen Godfrey | Issues in Light Meson Spectroscopy: The Case for Meson Spectroscopy at
Cebaf | 24 pages, uses worldsci.sty, figures available by fax after July 4
1994, OCIP/C 94-5 | null | null | null | hep-ph nucl-th | null | I review some outstanding issues in meson spectroscopy. The most important
qualitative issue is whether hadrons with explicit gluonic degrees of freedom
exist. To answer this question requires a much better understanding of
conventional $q\bar{q}$ mesons. I therefore begin by examining the status of
conventional meson spectroscopy and how the situation can be improved. The
expected properties of gluonic excitations are discussed with particular
emphasis on hybrids to give guidance to experimental searches. Multiquark
systems are commented upon as they are likely to be important in the mass
region under study and will have to be understood better. In the final section
I discuss the opportunities that CEBAF can offer for the study of meson
spectroscopy.
| [
{
"created": "Fri, 10 Jun 1994 12:56:56 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Godfrey",
"Stephen",
""
]
] | I review some outstanding issues in meson spectroscopy. The most important qualitative issue is whether hadrons with explicit gluonic degrees of freedom exist. To answer this question requires a much better understanding of conventional $q\bar{q}$ mesons. I therefore begin by examining the status of conventional meson spectroscopy and how the situation can be improved. The expected properties of gluonic excitations are discussed with particular emphasis on hybrids to give guidance to experimental searches. Multiquark systems are commented upon as they are likely to be important in the mass region under study and will have to be understood better. In the final section I discuss the opportunities that CEBAF can offer for the study of meson spectroscopy. |
2106.05296 | Matthias Steinhauser | Matteo Fael, Fabian Lange, Kay Sch\"onwald, Matthias Steinhauser | A semi-analytic method to compute Feynman integrals applied to four-loop
corrections to the $\overline{\rm MS}$-pole quark mass relation | 17 pages | null | 10.1007/JHEP09(2021)152 | P3H-21-041, TTP21-016 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We describe a method to numerically compute multi-loop integrals, depending
on one dimensionless parameter $x$ and the dimension $d$, in the whole
kinematic range of $x$. The method is based on differential equations, which,
however, do not require any special form, and series expansions around singular
and regular points. This method provides results well suited for fast numerical
evaluation and sufficiently precise for phenomenological applications. We apply
the approach to four-loop on-shell integrals and compute the coefficient
function of eight colour structures in the relation between the mass of a heavy
quark defined in the $\overline{\rm MS}$ and the on-shell scheme allowing for a
second non-zero quark mass. We also obtain analytic results for these eight
coefficient functions in terms of harmonic polylogarithms and iterated
integrals. This allows for a validation of the numerical accuracy.
| [
{
"created": "Wed, 9 Jun 2021 18:00:06 GMT",
"version": "v1"
}
] | 2021-10-13 | [
[
"Fael",
"Matteo",
""
],
[
"Lange",
"Fabian",
""
],
[
"Schönwald",
"Kay",
""
],
[
"Steinhauser",
"Matthias",
""
]
] | We describe a method to numerically compute multi-loop integrals, depending on one dimensionless parameter $x$ and the dimension $d$, in the whole kinematic range of $x$. The method is based on differential equations, which, however, do not require any special form, and series expansions around singular and regular points. This method provides results well suited for fast numerical evaluation and sufficiently precise for phenomenological applications. We apply the approach to four-loop on-shell integrals and compute the coefficient function of eight colour structures in the relation between the mass of a heavy quark defined in the $\overline{\rm MS}$ and the on-shell scheme allowing for a second non-zero quark mass. We also obtain analytic results for these eight coefficient functions in terms of harmonic polylogarithms and iterated integrals. This allows for a validation of the numerical accuracy. |
0705.1553 | Feng Yuan | Harut Avakian, Stanley J. Brodsky, Alexandre Deur, Feng Yuan | Effect of Orbital Angular Momentum on Valence-Quark Helicity
Distributions | 10 pages, 3 eps figures | Phys.Rev.Lett.99:082001,2007 | 10.1103/PhysRevLett.99.082001 | RBRC-671, SLAC-PUB-12503 | hep-ph | null | We study the quark helicity distributions at large x in perturbative QCD,
taking into account contributions from the valence Fock states of the nucleon
which have nonzero orbital angular momentum. These states are necessary to have
a nonzero anomalous magnetic moment. We find that the quark orbital angular
momentum contributes a large logarithm to the negative helicity quark
distributions in addition to its power behavior, scaling as (1-x)^5\log^2(1-x)
in the limit of x\to 1. Our analysis shows that the ratio of the polarized over
unpolarized down quark distributions, \Delta d/d, will still approach 1 in this
limit. By comparing with the experimental data, we find that this ratio should
cross zero at x\approx 0.75.
| [
{
"created": "Thu, 10 May 2007 21:56:43 GMT",
"version": "v1"
},
{
"created": "Sun, 13 May 2007 03:56:18 GMT",
"version": "v2"
}
] | 2008-12-18 | [
[
"Avakian",
"Harut",
""
],
[
"Brodsky",
"Stanley J.",
""
],
[
"Deur",
"Alexandre",
""
],
[
"Yuan",
"Feng",
""
]
] | We study the quark helicity distributions at large x in perturbative QCD, taking into account contributions from the valence Fock states of the nucleon which have nonzero orbital angular momentum. These states are necessary to have a nonzero anomalous magnetic moment. We find that the quark orbital angular momentum contributes a large logarithm to the negative helicity quark distributions in addition to its power behavior, scaling as (1-x)^5\log^2(1-x) in the limit of x\to 1. Our analysis shows that the ratio of the polarized over unpolarized down quark distributions, \Delta d/d, will still approach 1 in this limit. By comparing with the experimental data, we find that this ratio should cross zero at x\approx 0.75. |
hep-ph/0304262 | Genis Musulmanbekov | G. Musulmanbekov | Quark Correlations in Nucleons and Nuclei | 8 pages, 1 figure, to be published in Proc. Int. Conf. "Hadron
Structure'02", Kosice 2002 | null | null | null | hep-ph | null | A dynamical quark model of hadron and nucleus structure is proposed. In the
frame of the model, called the Strongly Correlated Quark Model, quarks and
nucleons inside nuclei are arranged in a crystal--like structure.
| [
{
"created": "Mon, 28 Apr 2003 09:38:31 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Apr 2003 21:09:21 GMT",
"version": "v2"
},
{
"created": "Mon, 5 May 2003 13:33:38 GMT",
"version": "v3"
},
{
"created": "Sun, 25 May 2003 19:35:12 GMT",
"version": "v4"
}
] | 2007-05-23 | [
[
"Musulmanbekov",
"G.",
""
]
] | A dynamical quark model of hadron and nucleus structure is proposed. In the frame of the model, called the Strongly Correlated Quark Model, quarks and nucleons inside nuclei are arranged in a crystal--like structure. |
2111.13633 | Gaia Grosso | Raffaele Tito d'Agnolo, Gaia Grosso, Maurizio Pierini, Andrea Wulzer
and Marco Zanetti | Learning New Physics from an Imperfect Machine | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show how to deal with uncertainties on the Standard Model predictions in
an agnostic new physics search strategy that exploits artificial neural
networks. Our approach builds directly on the specific Maximum Likelihood ratio
treatment of uncertainties as nuisance parameters for hypothesis testing that
is routinely employed in high-energy physics. After presenting the conceptual
foundations of our method, we first illustrate all aspects of its
implementation and extensively study its performances on a toy one-dimensional
problem. We then show how to implement it in a multivariate setup by studying
the impact of two typical sources of experimental uncertainties in two-body
final states at the LHC.
| [
{
"created": "Fri, 26 Nov 2021 17:52:54 GMT",
"version": "v1"
}
] | 2021-11-29 | [
[
"d'Agnolo",
"Raffaele Tito",
""
],
[
"Grosso",
"Gaia",
""
],
[
"Pierini",
"Maurizio",
""
],
[
"Wulzer",
"Andrea",
""
],
[
"Zanetti",
"Marco",
""
]
] | We show how to deal with uncertainties on the Standard Model predictions in an agnostic new physics search strategy that exploits artificial neural networks. Our approach builds directly on the specific Maximum Likelihood ratio treatment of uncertainties as nuisance parameters for hypothesis testing that is routinely employed in high-energy physics. After presenting the conceptual foundations of our method, we first illustrate all aspects of its implementation and extensively study its performances on a toy one-dimensional problem. We then show how to implement it in a multivariate setup by studying the impact of two typical sources of experimental uncertainties in two-body final states at the LHC. |
hep-ph/9609457 | J. Gunion | G. Anderson (FNAL), C.H. Chen (U.C. Davis), J.F. Gunion (U.C. Davis),
J. Lykken (FNAL), T. Moroi (LBL), Y. Yamada (Wisconsin) | Motivations for and Implications of Non-Universal GUT-Scale Boundary
Conditions for Soft SUSY-Breaking Parameters | 5 pages, full postscript file also available via anonymous ftp at
ftp://ucdhep.ucdavis.edu/gunion/nonuniversal_sm96.ps | null | null | UCD-96-25 | hep-ph hep-ex | null | We outline several well-motivated models in which GUT boundary conditions for
SUSY breaking are non-universal. The diverse phenomenological implications of
the non-universality for SUSY discovery at LEP2, the Tevatron, the LHC and the
NLC are sketched.
| [
{
"created": "Tue, 24 Sep 1996 21:14:33 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Anderson",
"G.",
"",
"FNAL"
],
[
"Chen",
"C. H.",
"",
"U.C. Davis"
],
[
"Gunion",
"J. F.",
"",
"U.C. Davis"
],
[
"Lykken",
"J.",
"",
"FNAL"
],
[
"Moroi",
"T.",
"",
"LBL"
],
[
"Yamada",
"Y.",
"",
"W... | We outline several well-motivated models in which GUT boundary conditions for SUSY breaking are non-universal. The diverse phenomenological implications of the non-universality for SUSY discovery at LEP2, the Tevatron, the LHC and the NLC are sketched. |
2010.16176 | Hui-Hui Duan | Hui-Hui Duan, Yong-Lu Liu and Ming-Qiu Huang | Semileptonic Decay of $\Omega_c^0 \to \Xi^- l^+ \nu_l$ From Light-Cone
Sum Rules | 10 pages, 7 figures | Eur. Phys. J. C (2021) 81:168 | 10.1140/epjc/s10052-021-08956-6 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The weak decay process of $\Omega_c$ to $\Xi$ is calculated in the method of
QCD light-cone sum rule. The decay width of $\Omega_c^0 \to \Xi^- l^+ \nu_l$
and its decay branching ratio are also calculated with the form factors from
this work's calculation. To the twist-6 distribution amplitudes, the form
factors $f_1=0.66\pm0.02, f_2=-0.76\pm0.03, g_1=0.06\pm0.01$ and
$g_2=-0.44\pm0.01$ are given at zero recoil point. The result of the
semileptonic decay width of $\Omega_c^0 \to \Xi^-l^+\nu_l$ is
$\Gamma=(7.51\pm0.36)\times10^{-15}~{\rm{GeV}}$ , and the prediction of the
decay branching ratio
$Br(\Omega_c^0\to\Xi^-l^+\nu_l)=(3.06\pm0.15)\times10^{-3}$. These results fit
well with other works, and the decay width and branching ratio are improved.
This not too small branching ratio gives a good direction to explore this decay
channel in the future experiments.
| [
{
"created": "Fri, 30 Oct 2020 10:31:07 GMT",
"version": "v1"
},
{
"created": "Mon, 18 Jan 2021 02:10:13 GMT",
"version": "v2"
}
] | 2021-02-23 | [
[
"Duan",
"Hui-Hui",
""
],
[
"Liu",
"Yong-Lu",
""
],
[
"Huang",
"Ming-Qiu",
""
]
] | The weak decay process of $\Omega_c$ to $\Xi$ is calculated in the method of QCD light-cone sum rule. The decay width of $\Omega_c^0 \to \Xi^- l^+ \nu_l$ and its decay branching ratio are also calculated with the form factors from this work's calculation. To the twist-6 distribution amplitudes, the form factors $f_1=0.66\pm0.02, f_2=-0.76\pm0.03, g_1=0.06\pm0.01$ and $g_2=-0.44\pm0.01$ are given at zero recoil point. The result of the semileptonic decay width of $\Omega_c^0 \to \Xi^-l^+\nu_l$ is $\Gamma=(7.51\pm0.36)\times10^{-15}~{\rm{GeV}}$ , and the prediction of the decay branching ratio $Br(\Omega_c^0\to\Xi^-l^+\nu_l)=(3.06\pm0.15)\times10^{-3}$. These results fit well with other works, and the decay width and branching ratio are improved. This not too small branching ratio gives a good direction to explore this decay channel in the future experiments. |
2401.01368 | Bastian D\'iaz S\'aez | Basti\'an D\'iaz S\'aez | An example of a bouncing dark matter -- EPS-HEP2023 | EPS-HEP2023. arXiv admin note: text overlap with arXiv:2307.07760 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Thermal dark matter, which, after chemical decoupling from the Standard Model
thermal plasma rises its yield before it freezes-out, is a new feature of
thermal DM scenarios dubbed as "Bouncing Dark Matter". In the following short
note, we introduce the topic, exemplifying the mechanism with a simple model
that extends the SM with two dark matter particles, a fermion, and a pNGB, plus
a second Higgs. We explore the features of the thermal freeze-out of this
scenario, with particular emphasis on the exponential growth of the yield of
the pNGB. We test the model under collider bounds, relic abundance, direct
detection, and we study prospects for indirect detection observables.
| [
{
"created": "Tue, 26 Dec 2023 14:11:15 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Mar 2024 13:47:00 GMT",
"version": "v2"
},
{
"created": "Thu, 2 May 2024 12:43:43 GMT",
"version": "v3"
}
] | 2024-05-03 | [
[
"Sáez",
"Bastián Díaz",
""
]
] | Thermal dark matter, which, after chemical decoupling from the Standard Model thermal plasma rises its yield before it freezes-out, is a new feature of thermal DM scenarios dubbed as "Bouncing Dark Matter". In the following short note, we introduce the topic, exemplifying the mechanism with a simple model that extends the SM with two dark matter particles, a fermion, and a pNGB, plus a second Higgs. We explore the features of the thermal freeze-out of this scenario, with particular emphasis on the exponential growth of the yield of the pNGB. We test the model under collider bounds, relic abundance, direct detection, and we study prospects for indirect detection observables. |
hep-ph/0207322 | Jairo Alexis Rodriguez | R. Martinez and J-Alexis Rodriguez | The Anomalous Chromomagnetic Dipole Moment of the Top Quark in Different
Frameworks | Presented at the XXII Physics in Collisions Conference (PIC02),
Stanford, Ca, USA, June 2002, 3 pages, LaTeX, 2 eps figures | eConf C020620:THAP06,2002 | null | null | hep-ph | null | We give explicit formulae for the anomalous chromomagnetic dipole moment of
the top quark in the framework of the standard model, the two higgs doublet
model and the minimal supersymmetric standard model. Finally, we compare the
results for this coupling with the bound -0.03 <= Delta kappa <= 0.01 coming
from analysis of b --> s gamma process whith an on-shell gluon.
| [
{
"created": "Fri, 26 Jul 2002 13:43:22 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Martinez",
"R.",
""
],
[
"Rodriguez",
"J-Alexis",
""
]
] | We give explicit formulae for the anomalous chromomagnetic dipole moment of the top quark in the framework of the standard model, the two higgs doublet model and the minimal supersymmetric standard model. Finally, we compare the results for this coupling with the bound -0.03 <= Delta kappa <= 0.01 coming from analysis of b --> s gamma process whith an on-shell gluon. |
1103.5992 | Christopher Smith | Philippe Mertens and Christopher Smith | The s ---> d gamma decay in and beyond the Standard Model | 54 pages, 14 eps figures | null | 10.1007/JHEP08(2011)069 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The New Physics sensitivity of the s ---> d gamma transition and its
accessibility through hadronic processes are thoroughly investigated. Firstly,
the Standard Model predictions for the direct CP-violating observables in
radiative K decays are systematically improved. Besides, the magnetic
contribution to epsilon prime is estimated and found subleading, even in the
presence of New Physics, and a new strategy to resolve its electroweak versus
QCD penguin fraction is identified. Secondly, the signatures of a series of New
Physics scenarios, characterized as model-independently as possible in terms of
their underlying dynamics, are investigated by combining the information from
all the FCNC transitions in the s ---> d sector.
| [
{
"created": "Wed, 30 Mar 2011 17:00:16 GMT",
"version": "v1"
}
] | 2015-05-27 | [
[
"Mertens",
"Philippe",
""
],
[
"Smith",
"Christopher",
""
]
] | The New Physics sensitivity of the s ---> d gamma transition and its accessibility through hadronic processes are thoroughly investigated. Firstly, the Standard Model predictions for the direct CP-violating observables in radiative K decays are systematically improved. Besides, the magnetic contribution to epsilon prime is estimated and found subleading, even in the presence of New Physics, and a new strategy to resolve its electroweak versus QCD penguin fraction is identified. Secondly, the signatures of a series of New Physics scenarios, characterized as model-independently as possible in terms of their underlying dynamics, are investigated by combining the information from all the FCNC transitions in the s ---> d sector. |
hep-ph/0605131 | Armen Oganesian Gourgenovitcv | A.G. Oganesian | Calculation of the pentaquark width by QCD sum rule | 8 Ppages, 3 figures,the numerical error was corrected, two figures
are modified. In the limit of errors the result did not change significantly | JETPLett.84:409-412,2006 | 10.1134/S002136400620001X | null | hep-ph | null | The pentaquark width is calculated in QCD sum rules. Result for
$\Gamma_{\Theta}$ show, that $\Gamma_{\Theta}$ can vary in the region less than
1$MeV$. The main conclusion is, that if pentaquark is genuine states then sum
rules really predict the narrow width of pentaquark $\theta^+$, and the
suppression of the width is both parametrical and numerical.
| [
{
"created": "Thu, 11 May 2006 14:35:07 GMT",
"version": "v1"
},
{
"created": "Mon, 22 May 2006 05:01:58 GMT",
"version": "v2"
},
{
"created": "Fri, 23 Jun 2006 17:24:02 GMT",
"version": "v3"
},
{
"created": "Thu, 3 Aug 2006 10:53:38 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Oganesian",
"A. G.",
""
]
] | The pentaquark width is calculated in QCD sum rules. Result for $\Gamma_{\Theta}$ show, that $\Gamma_{\Theta}$ can vary in the region less than 1$MeV$. The main conclusion is, that if pentaquark is genuine states then sum rules really predict the narrow width of pentaquark $\theta^+$, and the suppression of the width is both parametrical and numerical. |
hep-ph/9909419 | Roberto Casalbuoni | R. Casalbuoni and R. Gatto | The Color-Flavor Locking Phase at T \not =0$ | LateX, p. 14. Final version accepted for publication in Physics
Letters | Phys.Lett. B469 (1999) 213-219 | 10.1016/S0370-2693(99)01274-5 | null | hep-ph hep-th nucl-th | null | We study the color-flavor locked phase of QCD with three massless quarks at
high chemical potential and small non zero temperatures. We make use of the
recently introduced effective action to describe such a phase. We obtain the
exact order T^2 behaviour of the condensates and of the pressure by formally
comparing the derivative from the QCD functional with symmetry breaking to that
from the effective lagrangian with external sources, respecting the residual
Z_2 invariance of the color-flavor locked phase. From these exact results, but
now at a very tentative level of conjecture, we are lead to think that the
phase structure of QCD at very high density consists of two superconducting
phases and a symmetric one.
| [
{
"created": "Fri, 17 Sep 1999 14:25:49 GMT",
"version": "v1"
},
{
"created": "Wed, 3 Nov 1999 14:54:21 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Casalbuoni",
"R.",
""
],
[
"Gatto",
"R.",
""
]
] | We study the color-flavor locked phase of QCD with three massless quarks at high chemical potential and small non zero temperatures. We make use of the recently introduced effective action to describe such a phase. We obtain the exact order T^2 behaviour of the condensates and of the pressure by formally comparing the derivative from the QCD functional with symmetry breaking to that from the effective lagrangian with external sources, respecting the residual Z_2 invariance of the color-flavor locked phase. From these exact results, but now at a very tentative level of conjecture, we are lead to think that the phase structure of QCD at very high density consists of two superconducting phases and a symmetric one. |
1805.10914 | Gouranga Nayak | Gouranga C Nayak | Operator Product Expansion in QCD Is Not Consistent With Quantum Field
Theory For Gluon Distribution Function | 17 pages latex | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Since the operator product expansion (OPE) is applicable at short distance
the OPE in QCD does not solve the long distance confinement problem involving
hadron in QCD where the non-perturbative QCD is applicable. In this paper we
show that the gauge invariant definition of the non-perturbative gluon
distribution function inside the hadron consistent with the operator product
expansion (OPE) in QCD at high energy colliders is not consistent with the
gauge invariant definition of the non-perturbative gluon distribution function
in the quantum field theory.
| [
{
"created": "Mon, 28 May 2018 13:34:13 GMT",
"version": "v1"
}
] | 2018-05-31 | [
[
"Nayak",
"Gouranga C",
""
]
] | Since the operator product expansion (OPE) is applicable at short distance the OPE in QCD does not solve the long distance confinement problem involving hadron in QCD where the non-perturbative QCD is applicable. In this paper we show that the gauge invariant definition of the non-perturbative gluon distribution function inside the hadron consistent with the operator product expansion (OPE) in QCD at high energy colliders is not consistent with the gauge invariant definition of the non-perturbative gluon distribution function in the quantum field theory. |
2406.02949 | Mayengbam Kishan Singh | Mayengbam Kishan Singh and N. Nimai Singh | Exploring active-sterile neutrino mixings models in MES mechanism using
modular $S_3$ symmetry | null | null | null | null | hep-ph | http://creativecommons.org/licenses/by-sa/4.0/ | We study the minimal extended seesaw mechanism with one sterile neutrino in a
3+1 framework using modular $S_3$ symmetry. The active-sterile neutrino models
are classified based on the assignments of $S_3$ representations and modular
weights of the left-handed lepton doublets, triplet right-handed neutrino, and
sterile neutrino. No scalar flavons are considered, and the flavor symmetry is
broken by the vacuum expectation value (vev) of the modulus $\tau$. For a
particular set of representations of the Leptons and Higgs field, we obtain
eleven (11) different models based on different modular weights of charged
lepton $(k_L)$ and right-handed neutrino ($k_N$). Out of these, we consider two
models, which are discriminated by carrying out the numerical analysis so that
the parameter space in each model can fit the latest neutrino oscillation data
at 3$\sigma$. The Planck cosmological bound on the upper limit of the sum of
the active neutrino masses $\sum m_i <0.12$eV is also considered. Finally, the
best-fit parameters of the neutrino observables and model predictions are
evaluated using the minimum $\chi^2$ analysis.
| [
{
"created": "Wed, 5 Jun 2024 05:18:05 GMT",
"version": "v1"
}
] | 2024-06-06 | [
[
"Singh",
"Mayengbam Kishan",
""
],
[
"Singh",
"N. Nimai",
""
]
] | We study the minimal extended seesaw mechanism with one sterile neutrino in a 3+1 framework using modular $S_3$ symmetry. The active-sterile neutrino models are classified based on the assignments of $S_3$ representations and modular weights of the left-handed lepton doublets, triplet right-handed neutrino, and sterile neutrino. No scalar flavons are considered, and the flavor symmetry is broken by the vacuum expectation value (vev) of the modulus $\tau$. For a particular set of representations of the Leptons and Higgs field, we obtain eleven (11) different models based on different modular weights of charged lepton $(k_L)$ and right-handed neutrino ($k_N$). Out of these, we consider two models, which are discriminated by carrying out the numerical analysis so that the parameter space in each model can fit the latest neutrino oscillation data at 3$\sigma$. The Planck cosmological bound on the upper limit of the sum of the active neutrino masses $\sum m_i <0.12$eV is also considered. Finally, the best-fit parameters of the neutrino observables and model predictions are evaluated using the minimum $\chi^2$ analysis. |
hep-ph/0108127 | Ramon Toldra | Ramon Toldra | A C++ Code to Solve the DGLAP Equations Applied to Ultra High Energy
Cosmic Rays | 23 pages, revtex, 4 eps figures. Source code available from author or
from CPC program library. Typos corrected. References added. Accepted for
publication in Comput.Phys.Commun | Comput.Phys.Commun.143:287-304,2002 | 10.1016/S0010-4655(01)00458-1 | OUTP-01-47-P | hep-ph astro-ph | null | We solve numerically the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP)
equations for the evolution of fragmentation functions using the Laguerre
method. We extend this method to include supersymmetric evolution. The solution
to the DGLAP equations is particularly interesting to calculate the expected
spectra of Ultra High Energy Cosmic Rays in models where they are produced by
the decay of a massive particle X, M_X > 10^{12} GeV.
| [
{
"created": "Wed, 15 Aug 2001 16:40:19 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Jan 2002 16:24:44 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Toldra",
"Ramon",
""
]
] | We solve numerically the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) equations for the evolution of fragmentation functions using the Laguerre method. We extend this method to include supersymmetric evolution. The solution to the DGLAP equations is particularly interesting to calculate the expected spectra of Ultra High Energy Cosmic Rays in models where they are produced by the decay of a massive particle X, M_X > 10^{12} GeV. |
hep-ph/0312140 | Juan Antonio Aguilar-Saavedra | J. A. Aguilar-Saavedra | Study of selectron properties in the e~ e~ -> e- X_1^0 e- X_2^0 decay
channel | Latex, 18 pages. Contribution to the ECFA Study on Physics and
Detectors for a Linear Collider. Small changes in 4 figures | null | null | LC-TH-2003-098 | hep-ph | null | We discuss selectron pair production in e- e- scattering, in the processes e-
e- -> e~_L e~_L, e~_R e~_R -> e- X_1^0 e- X_2^0 -> e- X_1^0 e- X_1^0 f f. This
decay channel has in general a smaller branching ratio than the e~ e~ -> e-
X_1^0 e- X_1^0 mode, but has the advantage that the momenta of all final state
particles can be determined without using the selectron masses as input. The
reconstruction of the momenta allows the simultaneous study of: (i) selectron
mass distributions; (ii) selectron spins, via the angular distributions of the
e- in the selectron rest frames; (iii) selectron masses andspins, using the e-
energy distributions in the CM frame; (iv) the selectron "chirality", with the
analysis of the spin of the produced X_2^0.
| [
{
"created": "Wed, 10 Dec 2003 15:06:56 GMT",
"version": "v1"
},
{
"created": "Mon, 28 Jun 2004 17:26:30 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Aguilar-Saavedra",
"J. A.",
""
]
] | We discuss selectron pair production in e- e- scattering, in the processes e- e- -> e~_L e~_L, e~_R e~_R -> e- X_1^0 e- X_2^0 -> e- X_1^0 e- X_1^0 f f. This decay channel has in general a smaller branching ratio than the e~ e~ -> e- X_1^0 e- X_1^0 mode, but has the advantage that the momenta of all final state particles can be determined without using the selectron masses as input. The reconstruction of the momenta allows the simultaneous study of: (i) selectron mass distributions; (ii) selectron spins, via the angular distributions of the e- in the selectron rest frames; (iii) selectron masses andspins, using the e- energy distributions in the CM frame; (iv) the selectron "chirality", with the analysis of the spin of the produced X_2^0. |
2007.01850 | Taoli Cheng | Taoli Cheng, Jean-Fran\c{c}ois Arguin, Julien Leissner-Martin,
Jacinthe Pilette, Tobias Golling | Variational Autoencoders for Anomalous Jet Tagging | 36 pages, 23 figures. To appear in Physical Review D | Phys. Rev. D 107, 016002 (2023) | 10.1103/PhysRevD.107.016002 | null | hep-ph hep-ex stat.ML | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a detailed study on Variational Autoencoders (VAEs) for anomalous
jet tagging at the Large Hadron Collider. By taking in low-level jet
constituents' information, and training with background QCD jets in an
unsupervised manner, the VAE is able to encode important information for
reconstructing jets, while learning an expressive posterior distribution in the
latent space. When using the VAE as an anomaly detector, we present different
approaches to detect anomalies: directly comparing in the input space or,
instead, working in the latent space. In order to facilitate general search
approaches such as bump-hunt, mass-decorrelated VAEs based on distance
correlation regularization are also studied. We find that the naive
mass-decorrelated VAEs fail at maintaining proper detection performance, by
assigning higher probabilities to some anomalous samples. To build a performant
mass-decorrelated anomalous jet tagger, we propose the Outlier Exposed VAE
(OE-VAE), for which some outlier samples are introduced in the training process
to guide the learned information. OE-VAEs are employed to achieve two goals at
the same time: increasing sensitivity of outlier detection and decorrelating
jet mass from the anomaly score. We succeed in reaching excellent results from
both aspects. Code implementation of this work can be found at
https://github.com/taolicheng/VAE-Jet
| [
{
"created": "Fri, 3 Jul 2020 17:57:52 GMT",
"version": "v1"
},
{
"created": "Tue, 29 Sep 2020 17:28:43 GMT",
"version": "v2"
},
{
"created": "Mon, 15 Feb 2021 18:54:08 GMT",
"version": "v3"
},
{
"created": "Wed, 30 Nov 2022 03:48:08 GMT",
"version": "v4"
}
] | 2023-01-05 | [
[
"Cheng",
"Taoli",
""
],
[
"Arguin",
"Jean-François",
""
],
[
"Leissner-Martin",
"Julien",
""
],
[
"Pilette",
"Jacinthe",
""
],
[
"Golling",
"Tobias",
""
]
] | We present a detailed study on Variational Autoencoders (VAEs) for anomalous jet tagging at the Large Hadron Collider. By taking in low-level jet constituents' information, and training with background QCD jets in an unsupervised manner, the VAE is able to encode important information for reconstructing jets, while learning an expressive posterior distribution in the latent space. When using the VAE as an anomaly detector, we present different approaches to detect anomalies: directly comparing in the input space or, instead, working in the latent space. In order to facilitate general search approaches such as bump-hunt, mass-decorrelated VAEs based on distance correlation regularization are also studied. We find that the naive mass-decorrelated VAEs fail at maintaining proper detection performance, by assigning higher probabilities to some anomalous samples. To build a performant mass-decorrelated anomalous jet tagger, we propose the Outlier Exposed VAE (OE-VAE), for which some outlier samples are introduced in the training process to guide the learned information. OE-VAEs are employed to achieve two goals at the same time: increasing sensitivity of outlier detection and decorrelating jet mass from the anomaly score. We succeed in reaching excellent results from both aspects. Code implementation of this work can be found at https://github.com/taolicheng/VAE-Jet |
1912.05875 | Jo\~ao Tiago Neves Penedo | G. C. Branco, J. T. Penedo, Pedro M. F. Pereira, M. N. Rebelo, J. I.
Silva-Marcos | Type-I Seesaw with eV-Scale Neutrinos | 40 pages, 3 figures, 4 tables | null | 10.1007/JHEP07(2020)164 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider seesaw type-I models including at least one (mostly-)sterile
neutrino with mass at the eV scale. Three distinct situations are found, where
the presence of light extra neutrinos is naturally justified by an
approximately conserved lepton number symmetry. To analyse these scenarios
consistently, it is crucial to employ an exact parametrisation of the full
mixing matrix. We provide additional exact results, including generalised
versions of the seesaw relation and of the Casas-Ibarra parametrisation, valid
for every scale of seesaw. We find that the existence of a light sterile
neutrino imposes an upper bound on the lightest neutrino mass. We further
assess the impact of light sterile states on short- and long-baseline neutrino
oscillation experiments, emphasise future detection prospects, and address CP
Violation in this framework via the analysis of CP asymmetries and construction
of weak basis invariants. The proposed models can accommodate enough
active-sterile mixing to play a role in the explanation of short-baseline
anomalies.
| [
{
"created": "Thu, 12 Dec 2019 10:55:04 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Jan 2020 16:06:17 GMT",
"version": "v2"
}
] | 2020-08-26 | [
[
"Branco",
"G. C.",
""
],
[
"Penedo",
"J. T.",
""
],
[
"Pereira",
"Pedro M. F.",
""
],
[
"Rebelo",
"M. N.",
""
],
[
"Silva-Marcos",
"J. I.",
""
]
] | We consider seesaw type-I models including at least one (mostly-)sterile neutrino with mass at the eV scale. Three distinct situations are found, where the presence of light extra neutrinos is naturally justified by an approximately conserved lepton number symmetry. To analyse these scenarios consistently, it is crucial to employ an exact parametrisation of the full mixing matrix. We provide additional exact results, including generalised versions of the seesaw relation and of the Casas-Ibarra parametrisation, valid for every scale of seesaw. We find that the existence of a light sterile neutrino imposes an upper bound on the lightest neutrino mass. We further assess the impact of light sterile states on short- and long-baseline neutrino oscillation experiments, emphasise future detection prospects, and address CP Violation in this framework via the analysis of CP asymmetries and construction of weak basis invariants. The proposed models can accommodate enough active-sterile mixing to play a role in the explanation of short-baseline anomalies. |
hep-ph/9702357 | Casalbuoni Roberto | R. Casalbuoni, S. De Curtis and D. Dominici | Indirect effects of new resonances at future linear colliders | 14 pages, Latex, 1 fig | Phys.Lett. B403 (1997) 86-92 | 10.1016/S0370-2693(97)00512-1 | DFF 271/01/97 | hep-ph | null | In this paper we consider a general $SU(2)_L\otimes SU(2)_R$ invariant
Lagrangian describing scalar, vector and axial-vector resonances. By expanding
the WW and the ZZ scattering amplitude up to the fourth order in the external
momenta we can compare the parameters of our Lagrangian with the ones used in
the effective chiral Lagrangian formalism. In the last approach there has been
a recent study of the fusion processes at future e^+e^- colliders at energies
above 1 TeV. We use these results to put bounds on the parameter space of our
model and to show that for the case of vector resonances the bounds obtained
from the annihilation channel in fermion pairs are by far more restrictive,
already at energies of the order of 500 GeV.
| [
{
"created": "Tue, 18 Feb 1997 10:00:12 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Casalbuoni",
"R.",
""
],
[
"De Curtis",
"S.",
""
],
[
"Dominici",
"D.",
""
]
] | In this paper we consider a general $SU(2)_L\otimes SU(2)_R$ invariant Lagrangian describing scalar, vector and axial-vector resonances. By expanding the WW and the ZZ scattering amplitude up to the fourth order in the external momenta we can compare the parameters of our Lagrangian with the ones used in the effective chiral Lagrangian formalism. In the last approach there has been a recent study of the fusion processes at future e^+e^- colliders at energies above 1 TeV. We use these results to put bounds on the parameter space of our model and to show that for the case of vector resonances the bounds obtained from the annihilation channel in fermion pairs are by far more restrictive, already at energies of the order of 500 GeV. |
1910.08090 | Bei Zhou | Bei Zhou, John F. Beacom | Neutrino-nucleus cross sections for W-boson and trident production | Main text 14 pages and 13 figures; minor changes; results and
conclusions unchanged; matches published version | Phys. Rev. D 101, 036011 (2020) | 10.1103/PhysRevD.101.036011 | null | hep-ph astro-ph.HE nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The physics of neutrino-nucleus cross sections is a critical probe of the
Standard Model and beyond. A precise understanding is also needed to accurately
deduce astrophysical neutrino spectra. At energies above $\sim 5$ GeV, the
cross section is dominated by deep inelastic scattering, mediated by weak
bosons. In addition, there are subdominant processes where the hadronic
coupling is through virtual photons, $\gamma^\ast$: (on-shell) $W$-boson
production (e.g., where the underlying interaction is $\nu_\ell + \gamma^\ast
\rightarrow \ell^- + W^+$) and trident production (e.g., where it is $\nu +
\gamma^\ast \rightarrow \nu + \ell_1^- + \ell_2^+$). These processes become
increasingly relevant at TeV--PeV energies. We undertake the first systematic
approach to these processes (and those with hadronic couplings through virtual
$W$ and $Z$ bosons), treating them together, avoiding common approximations,
considering all neutrino flavors and final states, and covering the energy
range $10\,$--$10^8$ GeV. In particular, we present the first complete
calculation of $W$-boson production and the first calculation of trident
production at TeV--PeV energies. When we use the same assumptions as in prior
work, we recover all of their major results. In a companion paper, we show that
these processes should be taken into account for IceCube-Gen2.
| [
{
"created": "Thu, 17 Oct 2019 18:00:14 GMT",
"version": "v1"
},
{
"created": "Wed, 19 Feb 2020 00:32:46 GMT",
"version": "v2"
}
] | 2020-02-20 | [
[
"Zhou",
"Bei",
""
],
[
"Beacom",
"John F.",
""
]
] | The physics of neutrino-nucleus cross sections is a critical probe of the Standard Model and beyond. A precise understanding is also needed to accurately deduce astrophysical neutrino spectra. At energies above $\sim 5$ GeV, the cross section is dominated by deep inelastic scattering, mediated by weak bosons. In addition, there are subdominant processes where the hadronic coupling is through virtual photons, $\gamma^\ast$: (on-shell) $W$-boson production (e.g., where the underlying interaction is $\nu_\ell + \gamma^\ast \rightarrow \ell^- + W^+$) and trident production (e.g., where it is $\nu + \gamma^\ast \rightarrow \nu + \ell_1^- + \ell_2^+$). These processes become increasingly relevant at TeV--PeV energies. We undertake the first systematic approach to these processes (and those with hadronic couplings through virtual $W$ and $Z$ bosons), treating them together, avoiding common approximations, considering all neutrino flavors and final states, and covering the energy range $10\,$--$10^8$ GeV. In particular, we present the first complete calculation of $W$-boson production and the first calculation of trident production at TeV--PeV energies. When we use the same assumptions as in prior work, we recover all of their major results. In a companion paper, we show that these processes should be taken into account for IceCube-Gen2. |
2305.15461 | Zhiquan Sun | Rebecca von Kuk, Johannes K. L. Michel, and Zhiquan Sun | Transverse Momentum Distributions of Heavy Hadrons and Polarized Heavy
Quarks | 42 pages + references, 7 figures; v2: corrected matching for
heavy-quark Boer-Mulders function, journal version | null | 10.1007/JHEP09(2023)205 | MIT--CTP 5537, DESY 23--032 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We initiate the study of transverse momentum-dependent (TMD) fragmentation
functions for heavy quarks, demonstrate their factorization in terms of novel
nonperturbative matrix elements in heavy-quark effective theory (HQET), and
prove new TMD sum rules that arise from heavy-quark spin symmetry. We discuss
the phenomenology of heavy-quark TMD FFs at $B$ factories and find that the
Collins effect, in contrast to claims in the literature, is not parametrically
suppressed by the heavy-quark mass. We further calculate all TMD parton
distribution functions for the production of heavy quarks from polarized gluons
within the nucleon and use our results to demonstrate the potential of the
future EIC to resolve TMD heavy-quark fragmentation in semi-inclusive DIS,
complementing the planned EIC program to use heavy quarks as probes of gluon
distributions.
| [
{
"created": "Wed, 24 May 2023 18:00:00 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Oct 2023 19:27:29 GMT",
"version": "v2"
}
] | 2023-10-06 | [
[
"von Kuk",
"Rebecca",
""
],
[
"Michel",
"Johannes K. L.",
""
],
[
"Sun",
"Zhiquan",
""
]
] | We initiate the study of transverse momentum-dependent (TMD) fragmentation functions for heavy quarks, demonstrate their factorization in terms of novel nonperturbative matrix elements in heavy-quark effective theory (HQET), and prove new TMD sum rules that arise from heavy-quark spin symmetry. We discuss the phenomenology of heavy-quark TMD FFs at $B$ factories and find that the Collins effect, in contrast to claims in the literature, is not parametrically suppressed by the heavy-quark mass. We further calculate all TMD parton distribution functions for the production of heavy quarks from polarized gluons within the nucleon and use our results to demonstrate the potential of the future EIC to resolve TMD heavy-quark fragmentation in semi-inclusive DIS, complementing the planned EIC program to use heavy quarks as probes of gluon distributions. |
1001.4207 | Andrei Kataev | A.L. Kataev (INR, Moscow) and V.T.Kim (St.Petersburg NPI, Gatchina) | Peculiar features of the relations between pole and running heavy quark
masses and estimates of the O(\alpha_s^4) contributions | Presented at the Conference "Problems of Theoretical and Mathematical
Physics", dedicated to 100th anniversary of the birth of N.N. Bogolyubov,
Dubna,August 23-27, 2009 and 9th Symposium on RADCOR-2009, October 25-30,
2009, Ascona; typos corrected,results unchanged | Phys.Part.Nucl.41:946-950,2010 | 10.1134/S1063779610060262 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Perturbative relations between pole and running heavy quark masses, defined
in the Minkowski regions, are considered. Special attention is paid to the
appearance of the kinematic $\pi^2$-effects, which exist in the coefficients of
these series. The estimates of order $O(\alpha_s^4)$ QCD corrections are
presented.
| [
{
"created": "Sat, 23 Jan 2010 21:38:39 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Mar 2010 10:22:16 GMT",
"version": "v2"
}
] | 2010-12-09 | [
[
"Kataev",
"A. L.",
"",
"INR, Moscow"
],
[
"Kim",
"V. T.",
"",
"St.Petersburg NPI, Gatchina"
]
] | Perturbative relations between pole and running heavy quark masses, defined in the Minkowski regions, are considered. Special attention is paid to the appearance of the kinematic $\pi^2$-effects, which exist in the coefficients of these series. The estimates of order $O(\alpha_s^4)$ QCD corrections are presented. |
2103.03262 | Ravi Kuchimanchi | Ravi Kuchimanchi | Bayesian probability for leptonic CP phase with strong CP prior | 9 pages, 2 figs, 4 tables | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In a world devoid of axions, the smallness of the strong CP phase can have
implications for leptonic CP violation being probed by neutrino experiments.
For example, if nature adopted an axionless solution to the strong CP problem,
the same symmetries that set the strong CP phase to zero at the tree-level, may
also set the leptonic $CP$ phases to zero (mod \pi). This automatically happens
in the left-right symmetric model when it is extended minimally to solve the
strong CP problem by imposition of both P and CP. In the Nelson Barr solution
the needed symmetries can be assigned so that leptonic CP violation is not
generated. In the minimal left-right symmetric model with P (and not CP), where
the strong CP problem remains, leptonic CP phases radiatively generate the
strong CP phase in one loop, and therefore they may be absent (negligibly
small) in large regions of parameter space. All these results motivate us to
consider a Bayesian prior for leptonic Dirac CP phase \delta_{CP} of the PMNS
matrix that has delta function like peaks at CP conserving values of 0 and \pi
on top of a uniform distribution. We evaluate the posterior probability
distribution for \delta_{CP} using the current global fit to neutrino
experiments and find significant enhancements for the probability that
\delta_{CP} is at or negligibly close to \pi. We also provide useful tables for
the posterior probability considering present and future experimental
sensitivities.
| [
{
"created": "Thu, 4 Mar 2021 19:00:10 GMT",
"version": "v1"
}
] | 2021-03-08 | [
[
"Kuchimanchi",
"Ravi",
""
]
] | In a world devoid of axions, the smallness of the strong CP phase can have implications for leptonic CP violation being probed by neutrino experiments. For example, if nature adopted an axionless solution to the strong CP problem, the same symmetries that set the strong CP phase to zero at the tree-level, may also set the leptonic $CP$ phases to zero (mod \pi). This automatically happens in the left-right symmetric model when it is extended minimally to solve the strong CP problem by imposition of both P and CP. In the Nelson Barr solution the needed symmetries can be assigned so that leptonic CP violation is not generated. In the minimal left-right symmetric model with P (and not CP), where the strong CP problem remains, leptonic CP phases radiatively generate the strong CP phase in one loop, and therefore they may be absent (negligibly small) in large regions of parameter space. All these results motivate us to consider a Bayesian prior for leptonic Dirac CP phase \delta_{CP} of the PMNS matrix that has delta function like peaks at CP conserving values of 0 and \pi on top of a uniform distribution. We evaluate the posterior probability distribution for \delta_{CP} using the current global fit to neutrino experiments and find significant enhancements for the probability that \delta_{CP} is at or negligibly close to \pi. We also provide useful tables for the posterior probability considering present and future experimental sensitivities. |
hep-ph/0511133 | Ernest Ma | Ernest Ma (UC Riverside) | Tribimaximal Neutrino Mixing from a Supersymmetric Model with A_4 Family
Symmetry | published version; title changed in journal | Phys.Rev.D73:057304,2006 | 10.1103/PhysRevD.73.057304 | UCRHEP-T402 (Nov 05) | hep-ph | null | In the supersymmetric seesaw model of neutrino masses, augmented by the
non-Abelian discrete tetrahedral symmetry A_4, a specific pattern of neutrino
mixing is automatically generated if one of the three heavy singlet neutrino
superfields acquires a nonzero vacuum expectation value. This pattern turns out
to be exactly that of tribimaximal mixing, i.e. sin^2 theta_23 = 1/2, sin^2
theta_12 = 1/3, and sin^2 theta_13 = 0, in good agreement with data.
| [
{
"created": "Thu, 10 Nov 2005 16:31:01 GMT",
"version": "v1"
},
{
"created": "Fri, 18 Nov 2005 18:18:50 GMT",
"version": "v2"
},
{
"created": "Mon, 22 May 2006 15:02:22 GMT",
"version": "v3"
}
] | 2010-04-06 | [
[
"Ma",
"Ernest",
"",
"UC Riverside"
]
] | In the supersymmetric seesaw model of neutrino masses, augmented by the non-Abelian discrete tetrahedral symmetry A_4, a specific pattern of neutrino mixing is automatically generated if one of the three heavy singlet neutrino superfields acquires a nonzero vacuum expectation value. This pattern turns out to be exactly that of tribimaximal mixing, i.e. sin^2 theta_23 = 1/2, sin^2 theta_12 = 1/3, and sin^2 theta_13 = 0, in good agreement with data. |
hep-ph/9801378 | Albert de Roeck | A. De Roeck (DESY) | Topics on the Physics Potential and Detector Aspects of the LC-HERA ep
Collider | 11 pages including 6 figures | Turk.J.Phys. 22 (1998) 595-606 | null | DESY 97-250 | hep-ph | null | We give a brief account of some physics topics which could be addressed at a
collider consisting of the HERA proton ring and the future e+e- Linear
Collider. A few experimental aspects are also discussed.
| [
{
"created": "Wed, 21 Jan 1998 18:15:25 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"De Roeck",
"A.",
"",
"DESY"
]
] | We give a brief account of some physics topics which could be addressed at a collider consisting of the HERA proton ring and the future e+e- Linear Collider. A few experimental aspects are also discussed. |
2311.02186 | Gergely Fejos | G. Fejos, A. Patkos | Thermal behavior of effective U_A(1) anomaly couplings in reflection of
higher topological sectors | 11 pages, 8 figures, matches published version | Phys. Rev. D 109, 036035 (2024) | 10.1103/PhysRevD.109.036035 | RIKEN-iTHEMS-Report-23 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Thermal behavior of effective, chiral condensate-dependent $U_A(1)$ anomaly
couplings is investigated using the functional renormalization group approach
in the $N_f = 3$ flavor meson model. We derive flow equations for anomaly
couplings that arise from instantons of higher topological charge, dependent
also on the chiral condensate. These flow equations are solved numerically for
the $|Q|=1,2$ topological sectors at finite temperature. Assuming that the
anomaly couplings at the ultraviolet scale may also exhibit explicit
temperature dependence, we calculate the thermal behavior of the effective
potential. In accordance with our earlier study, [G. Fejos and A. Patkos, Phys.
Rev. D{\bf 105}, 096007 (2022)], we find that for increasing temperatures, the
anomalous breaking of chiral symmetry tends to strengthen toward the
pseudocritical temperature ($T_C$) of chiral symmetry breaking. It is revealed
that below $T_C$, around $\sim$10\% of the $U_A(1)$ breaking arises from the
$|Q|=2$ topological sector. Correspondingly, a detailed analysis on the thermal
behavior of the mass spectrum is also presented.
| [
{
"created": "Fri, 3 Nov 2023 18:36:10 GMT",
"version": "v1"
},
{
"created": "Tue, 27 Feb 2024 23:09:15 GMT",
"version": "v2"
}
] | 2024-02-29 | [
[
"Fejos",
"G.",
""
],
[
"Patkos",
"A.",
""
]
] | Thermal behavior of effective, chiral condensate-dependent $U_A(1)$ anomaly couplings is investigated using the functional renormalization group approach in the $N_f = 3$ flavor meson model. We derive flow equations for anomaly couplings that arise from instantons of higher topological charge, dependent also on the chiral condensate. These flow equations are solved numerically for the $|Q|=1,2$ topological sectors at finite temperature. Assuming that the anomaly couplings at the ultraviolet scale may also exhibit explicit temperature dependence, we calculate the thermal behavior of the effective potential. In accordance with our earlier study, [G. Fejos and A. Patkos, Phys. Rev. D{\bf 105}, 096007 (2022)], we find that for increasing temperatures, the anomalous breaking of chiral symmetry tends to strengthen toward the pseudocritical temperature ($T_C$) of chiral symmetry breaking. It is revealed that below $T_C$, around $\sim$10\% of the $U_A(1)$ breaking arises from the $|Q|=2$ topological sector. Correspondingly, a detailed analysis on the thermal behavior of the mass spectrum is also presented. |
hep-ph/9907348 | Naomichi Suzuki | N.Suzuki and M.Biyajima | Multiplicity dependence of identical particle correlations in the
quantum optical approach | 14 pages, 7 figures | Phys.Rev. C60 (1999) 034903 | 10.1103/PhysRevC.60.034903 | null | hep-ph | null | Identical particle correlations at fixed multiplicity are consideres in the
presence of chaotic and coherent fields. The multiplicity distribution,
one-particle momentum density, and two-particle correlation function are
obtained based on the diagrammatic representation for cmulants in
semi-inclusive events. Our formulation is applied to the analysis of the
experimental data on the multiplicity dependence of correlation functions
reported by the UA1 and the OPAL Collaborations.
| [
{
"created": "Wed, 14 Jul 1999 02:07:59 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Suzuki",
"N.",
""
],
[
"Biyajima",
"M.",
""
]
] | Identical particle correlations at fixed multiplicity are consideres in the presence of chaotic and coherent fields. The multiplicity distribution, one-particle momentum density, and two-particle correlation function are obtained based on the diagrammatic representation for cmulants in semi-inclusive events. Our formulation is applied to the analysis of the experimental data on the multiplicity dependence of correlation functions reported by the UA1 and the OPAL Collaborations. |
hep-ph/0307077 | Maxim V. Polyakov | V. Yu. Petrov and M. V. Polyakov | Light cone nucleon wave function in the quark-soliton model | 23 pages, 2 figures, references added | null | null | PNPI-2500, RUB-TP2-19/02 | hep-ph hep-ex nucl-th | null | The light-cone wave function of the nucleon is calculated in the limit
N_c -> infinity in the quark-soliton model inspired by the theory of the
instanton vacuum of QCD. The technique of the finite time evolution operator is
used in order to derive expressions for all components of the Fock vector
describing the nucleon in the infinite momentum frame. It is shown that nucleon
wave function for large N_c can be expressed in terms of the wave function of
the discrete level in the self-consistent meson field and light cone wave
functions of 1,2, etc mesons. The 3-quark components of the nucleon and
Delta-resonance are estimated. Wave function of the nucleon appears to be
positive in the whole region of x and it has rather small asymmetry. It differs
strongly both from Chernyak-Zhitnitsky wave function and the asymptotic one.
Large momentum transfer asymptotic of the electromagnetic and axial form
factors is discussed.
| [
{
"created": "Sat, 5 Jul 2003 17:48:32 GMT",
"version": "v1"
},
{
"created": "Tue, 22 Jul 2003 09:13:00 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Petrov",
"V. Yu.",
""
],
[
"Polyakov",
"M. V.",
""
]
] | The light-cone wave function of the nucleon is calculated in the limit N_c -> infinity in the quark-soliton model inspired by the theory of the instanton vacuum of QCD. The technique of the finite time evolution operator is used in order to derive expressions for all components of the Fock vector describing the nucleon in the infinite momentum frame. It is shown that nucleon wave function for large N_c can be expressed in terms of the wave function of the discrete level in the self-consistent meson field and light cone wave functions of 1,2, etc mesons. The 3-quark components of the nucleon and Delta-resonance are estimated. Wave function of the nucleon appears to be positive in the whole region of x and it has rather small asymmetry. It differs strongly both from Chernyak-Zhitnitsky wave function and the asymptotic one. Large momentum transfer asymptotic of the electromagnetic and axial form factors is discussed. |
hep-ph/9408372 | null | W.-K. Tang | Anomalous Charm Production at Large $x_{F}$ | 16 pages | null | null | null | hep-ph | null | We show that the new QCD production mechanisms which were proposed by S. J.
Brodsky, P. Hoyer, A. H. Mueller and the author can explain at least some of
the anomalous behavior of open and/or closed charm production at large $x_{F}$.
| [
{
"created": "Thu, 25 Aug 1994 21:20:00 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Tang",
"W. -K.",
""
]
] | We show that the new QCD production mechanisms which were proposed by S. J. Brodsky, P. Hoyer, A. H. Mueller and the author can explain at least some of the anomalous behavior of open and/or closed charm production at large $x_{F}$. |
2009.04288 | Harleen Dahiya Dr. | Satvir Kaur, Chandan Mondal, Harleen Dahiya | Light-front holographic $\rho$-meson distributions in the momentum space | 41 pages, 11 figures; To appear in JHEP | null | 10.1007/JHEP01(2021)136 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the leading-twist quark transverse momentum-dependent parton
distribution functions (TMDs) for the spin-1 target, such as the $\rho$-meson,
in the light-front framework. Specifically, we predict the TMDs in the
light-front holographic model and compare with the light-front quark model
predictions. We obtain the TMDs using the overlap of the light-front wave
functions. We evaluate the ${\bf k}_\perp$ moments upto second order and
compare with the available theoretical predictions. Further, we analyze the
leading-twist parton distribution functions (PDFs) of the $\rho$-meson in the
light-front holographic model which are found to be in accord with the
Nambu-Jona-Lasinio (NJL) model and the light-front quark model predictions. We
further study the QCD evolution of the PDFs. The positivity bounds on the TMDs
and the PDFs are also discussed. We also present the quark spin densities in
the transverse momentum plane for different polarization configurations of the
quark and the $\rho$-meson target.
| [
{
"created": "Wed, 9 Sep 2020 13:21:29 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Dec 2020 13:25:45 GMT",
"version": "v2"
}
] | 2021-02-24 | [
[
"Kaur",
"Satvir",
""
],
[
"Mondal",
"Chandan",
""
],
[
"Dahiya",
"Harleen",
""
]
] | We present the leading-twist quark transverse momentum-dependent parton distribution functions (TMDs) for the spin-1 target, such as the $\rho$-meson, in the light-front framework. Specifically, we predict the TMDs in the light-front holographic model and compare with the light-front quark model predictions. We obtain the TMDs using the overlap of the light-front wave functions. We evaluate the ${\bf k}_\perp$ moments upto second order and compare with the available theoretical predictions. Further, we analyze the leading-twist parton distribution functions (PDFs) of the $\rho$-meson in the light-front holographic model which are found to be in accord with the Nambu-Jona-Lasinio (NJL) model and the light-front quark model predictions. We further study the QCD evolution of the PDFs. The positivity bounds on the TMDs and the PDFs are also discussed. We also present the quark spin densities in the transverse momentum plane for different polarization configurations of the quark and the $\rho$-meson target. |
2101.10603 | Yu-Gang Ma | D. F. Wang, S. Zhang, Y. G. Ma | System size dependence of baryon-strangeness correlations in
relativistic heavy ion collisions from a multiphase transport model | 8 pages, 2 tables, 7 figures; Phys. Rev. C, in press | Phys. Rev. C 103, 024901 (2021) | 10.1103/PhysRevC.103.024901 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | The system size dependence of baryon-strangeness (BS) correlations ($C_{BS}$)
are investigated with a multiphase transport (AMPT) model for various collision
systems from $\mathrm{^{10}B+^{10}B}$, $\mathrm{^{12}C+^{12}C}$,
$\mathrm{^{16}O+^{16}O}$, $\mathrm{^{20}Ne+^{20}Ne}$,
$\mathrm{^{40}Ca+^{40}Ca}$, $\mathrm{^{96}Zr+^{96}Zr}$, and
$\mathrm{^{197}Au+^{197}Au}$ at RHIC energies $\sqrt{s_{NN}}$ of 200, 39, 27,
20, and 7.7 GeV. Both effects of hadron rescattering and a combination of
different hadrons play a leading role for baryon-strangeness correlations. When
the kinetic window is limited to absolute rapidity $|y|>3$, these correlations
tend to be constant after the final-state interaction whatever kind of hadrons
subset we chose based on the AMPT framework. The correlation is found to
smoothly increase with baryon chemical potential $\mu_B$, corresponding to the
collision system or energy from the quark-gluon-plasma-like phase to the
hadron-gas-like phase. Besides, the influence of initial nuclear geometrical
structures of $\alpha$-clustered nuclear collision systems of
$\mathrm{^{12}C+^{12}C}$ as well as $\mathrm{^{16}O+^{16}O}$ collisions is
discussed but the effect is found negligible. The current model studies provide
baselines for searching for the signals of Quantum Chromodynamics (QCD) phase
transition and critical point in heavy-ion collisions through the BS
correlation.
| [
{
"created": "Tue, 26 Jan 2021 07:31:36 GMT",
"version": "v1"
}
] | 2021-02-10 | [
[
"Wang",
"D. F.",
""
],
[
"Zhang",
"S.",
""
],
[
"Ma",
"Y. G.",
""
]
] | The system size dependence of baryon-strangeness (BS) correlations ($C_{BS}$) are investigated with a multiphase transport (AMPT) model for various collision systems from $\mathrm{^{10}B+^{10}B}$, $\mathrm{^{12}C+^{12}C}$, $\mathrm{^{16}O+^{16}O}$, $\mathrm{^{20}Ne+^{20}Ne}$, $\mathrm{^{40}Ca+^{40}Ca}$, $\mathrm{^{96}Zr+^{96}Zr}$, and $\mathrm{^{197}Au+^{197}Au}$ at RHIC energies $\sqrt{s_{NN}}$ of 200, 39, 27, 20, and 7.7 GeV. Both effects of hadron rescattering and a combination of different hadrons play a leading role for baryon-strangeness correlations. When the kinetic window is limited to absolute rapidity $|y|>3$, these correlations tend to be constant after the final-state interaction whatever kind of hadrons subset we chose based on the AMPT framework. The correlation is found to smoothly increase with baryon chemical potential $\mu_B$, corresponding to the collision system or energy from the quark-gluon-plasma-like phase to the hadron-gas-like phase. Besides, the influence of initial nuclear geometrical structures of $\alpha$-clustered nuclear collision systems of $\mathrm{^{12}C+^{12}C}$ as well as $\mathrm{^{16}O+^{16}O}$ collisions is discussed but the effect is found negligible. The current model studies provide baselines for searching for the signals of Quantum Chromodynamics (QCD) phase transition and critical point in heavy-ion collisions through the BS correlation. |
1509.02197 | Paulo Victor Recchia Gomes Silva | D.A. Fagundes, L. Jenkovszky, E.Q. Miranda, G. Pancheri, P.V.R.G.
Silva | Fine structure of the diffraction cone: from ISR to the LHC | 11 pages, 6 figures, 7 tables. Invited contribution to the Gribov-85
Memorial Volume "Exploring Quantum Field Theory", to be published by World
Scientific | Gribov-85 Memorial Volume: Exploring Quantum Field Theory: pp.
180-194 (World Scientific, 2016) | 10.1142/9789813141704_0022 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Following earlier findings, we argue that the low-$|t|$ structure in the
elastic diffractive cone, recently reported by the TOTEM Collaboration at $8$
TeV, is a consequence of the threshold singularity required by $t-$channel
unitarity, such as revealed earlier at the ISR. By using simple Regge-pole
models, we analyze the available data on the $pp$ elastic differential cross
section in a wide range of c.m. energies, namely those from ISR to LHC8,
obtaining good fits of all datasets. This study hints at the fact that the
non-exponential behaviour observed at LHC8 is a recurrence of the low-$|t|$
"break" phenomenon, observed in the seventies at ISR, being induced by the
presence of a two-pion loop singularity in the Pomeron trajectory.
| [
{
"created": "Mon, 7 Sep 2015 21:21:45 GMT",
"version": "v1"
}
] | 2016-10-18 | [
[
"Fagundes",
"D. A.",
""
],
[
"Jenkovszky",
"L.",
""
],
[
"Miranda",
"E. Q.",
""
],
[
"Pancheri",
"G.",
""
],
[
"Silva",
"P. V. R. G.",
""
]
] | Following earlier findings, we argue that the low-$|t|$ structure in the elastic diffractive cone, recently reported by the TOTEM Collaboration at $8$ TeV, is a consequence of the threshold singularity required by $t-$channel unitarity, such as revealed earlier at the ISR. By using simple Regge-pole models, we analyze the available data on the $pp$ elastic differential cross section in a wide range of c.m. energies, namely those from ISR to LHC8, obtaining good fits of all datasets. This study hints at the fact that the non-exponential behaviour observed at LHC8 is a recurrence of the low-$|t|$ "break" phenomenon, observed in the seventies at ISR, being induced by the presence of a two-pion loop singularity in the Pomeron trajectory. |
2004.13656 | Dmitry Kirpichnikov | D. V. Kirpichnikov, Valery E. Lyubovitskij and Alexey S. Zhevlakov | Constraints on CP-odd ALP couplings from EDM limits of fermions | 12 pages, 2 figures, journal reference corrected | Particles 2020, 3, 719-728 | 10.3390/particles3040047 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss constraints on soft CP-violating couplings of axion-like particles
with photon and fermions by using data on electric dipole moments of Standard
Model particles. In particular, for the ALP leptophilic scenario we derive
bounds on CP-odd ALP-photon-photon coupling from data of the {\tt ACME}
Collaboration on electron EDM. We also discuss prospects of the Storage Ring
experiment to constrain the ALP-photon-photon coupling from data on proton EDM
for the simplified hadrophilic interactions of ALP. The regarding constraints
from experimental bounds on the muon and neutron EDMs are weak. We set
constraint on the CP-odd ALP coupling with electron and derive bounds on
combinations of coupling constants, which involve soft CP-violating terms.
| [
{
"created": "Tue, 28 Apr 2020 16:59:34 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Dec 2020 15:47:32 GMT",
"version": "v2"
},
{
"created": "Mon, 21 Dec 2020 13:46:36 GMT",
"version": "v3"
},
{
"created": "Fri, 25 Dec 2020 13:03:55 GMT",
"version": "v4"
}
] | 2020-12-29 | [
[
"Kirpichnikov",
"D. V.",
""
],
[
"Lyubovitskij",
"Valery E.",
""
],
[
"Zhevlakov",
"Alexey S.",
""
]
] | We discuss constraints on soft CP-violating couplings of axion-like particles with photon and fermions by using data on electric dipole moments of Standard Model particles. In particular, for the ALP leptophilic scenario we derive bounds on CP-odd ALP-photon-photon coupling from data of the {\tt ACME} Collaboration on electron EDM. We also discuss prospects of the Storage Ring experiment to constrain the ALP-photon-photon coupling from data on proton EDM for the simplified hadrophilic interactions of ALP. The regarding constraints from experimental bounds on the muon and neutron EDMs are weak. We set constraint on the CP-odd ALP coupling with electron and derive bounds on combinations of coupling constants, which involve soft CP-violating terms. |
1109.6243 | Claudia Ratti | Claudia Ratti, Rene Bellwied, Marco Cristoforetti, Maria Barbaro | Are there hadronic bound states above the QCD transition temperature? | 15 pages, 4 Figures | null | 10.1103/PhysRevD.85.014004 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent lattice QCD calculations, at physical pion masses and small lattice
spacings that approach the continuum limit, have revealed that non-diagonal
quark correlators above the critical temperature are finite up to about 2
$T_c$. Since the transition from hadronic to free partonic degrees of freedom
is merely an analytic cross-over, it is likely that, in the temperature regime
between 1-2 $T_c$, quark and gluon quasiparticles and pre-hadronic bound states
can coexist. The correlator values, in comparison to PNJL model calculations
beyond mean-field, indicate that at least part of the mixed phase resides in
color-neutral bound states. A similar effect was postulated for the in-medium
fragmentation process, i.e. for partons which do not thermalize with the system
and thus constitute the non-equilibrium component of the particle emission
spectrum from a deconfined plasma phase. Here, for the first time we
investigate the likelihood of forming bound states also in the equilibrated,
parton dominated phase above $T_c$ which is described by lattice QCD.
| [
{
"created": "Wed, 28 Sep 2011 15:33:48 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Ratti",
"Claudia",
""
],
[
"Bellwied",
"Rene",
""
],
[
"Cristoforetti",
"Marco",
""
],
[
"Barbaro",
"Maria",
""
]
] | Recent lattice QCD calculations, at physical pion masses and small lattice spacings that approach the continuum limit, have revealed that non-diagonal quark correlators above the critical temperature are finite up to about 2 $T_c$. Since the transition from hadronic to free partonic degrees of freedom is merely an analytic cross-over, it is likely that, in the temperature regime between 1-2 $T_c$, quark and gluon quasiparticles and pre-hadronic bound states can coexist. The correlator values, in comparison to PNJL model calculations beyond mean-field, indicate that at least part of the mixed phase resides in color-neutral bound states. A similar effect was postulated for the in-medium fragmentation process, i.e. for partons which do not thermalize with the system and thus constitute the non-equilibrium component of the particle emission spectrum from a deconfined plasma phase. Here, for the first time we investigate the likelihood of forming bound states also in the equilibrated, parton dominated phase above $T_c$ which is described by lattice QCD. |
hep-ph/0311059 | Adrian Signer | D.A. Forde and A.Signer | Infrared-Finite Amplitudes for Massless Gauge Theories | 46 pages | Nucl.Phys. B684 (2004) 125-161 | 10.1016/j.nuclphysb.2004.02.024 | IPPP/03/67 | hep-ph | null | We present a method to construct infrared-finite amplitudes for gauge
theories with massless fermions. Rather than computing $S$-matrix elements
between usual states of the Fock space we construct order-by-order in
perturbation theory dressed states that incorporate all long-range
interactions. The $S$-matrix elements between these states are shown to be free
from soft and collinear singularities. As an explicit example we consider the
process $e^+ e^-\to 2$ jets at next-to-leading order in the strong coupling. We
verify by explicit calculation that the amplitudes are infrared finite and
recover the well-known result for the total cross section $e^+ e^-\to$ hadrons.
| [
{
"created": "Wed, 5 Nov 2003 12:16:43 GMT",
"version": "v1"
},
{
"created": "Tue, 23 Mar 2004 10:44:14 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Forde",
"D. A.",
""
],
[
"Signer",
"A.",
""
]
] | We present a method to construct infrared-finite amplitudes for gauge theories with massless fermions. Rather than computing $S$-matrix elements between usual states of the Fock space we construct order-by-order in perturbation theory dressed states that incorporate all long-range interactions. The $S$-matrix elements between these states are shown to be free from soft and collinear singularities. As an explicit example we consider the process $e^+ e^-\to 2$ jets at next-to-leading order in the strong coupling. We verify by explicit calculation that the amplitudes are infrared finite and recover the well-known result for the total cross section $e^+ e^-\to$ hadrons. |
2210.15388 | Anowar Shaikh | Anowar Shaikh, Shubhalaxmi Rath, Sadhana Dash, and Binata Panda | Flow of charge and heat in thermal QCD within the weak magnetic field
limit: A BGK model approach | 41 pages, 26 figures | null | null | null | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have computed the charge and heat transport coefficients of hot QCD matter
by solving the relativistic Boltzmann transport equation using the BGK model
approximation with a modified collision integral in the weak magnetic field
regime. This modified collision integral enhances both charge and heat
transport phenomena which can be understood by the large values of the
above-mentioned coefficients in comparison to the relaxation collision
integral. We have also presented a comparative study of coefficients like the
electrical conductivity ($\sigma_{el}$), Hall conductivity ($\sigma_{H}$),
thermal conductivity ($\kappa$) and Hall-type thermal
conductivity($\kappa_{H}$) in weak and strong magnetic fields in the BGK model
approximation. The effects of weak magnetic field and finite chemical potential
on the transport coefficients have been explored using a quasiparticle model.
Moreover, we have also studied the effects of weak magnetic field and finite
chemical potential on Lorenz number, Knudsen number, specific heat, elliptic
flow and Wiedemann-Franz law.
| [
{
"created": "Thu, 27 Oct 2022 12:48:19 GMT",
"version": "v1"
}
] | 2022-10-28 | [
[
"Shaikh",
"Anowar",
""
],
[
"Rath",
"Shubhalaxmi",
""
],
[
"Dash",
"Sadhana",
""
],
[
"Panda",
"Binata",
""
]
] | We have computed the charge and heat transport coefficients of hot QCD matter by solving the relativistic Boltzmann transport equation using the BGK model approximation with a modified collision integral in the weak magnetic field regime. This modified collision integral enhances both charge and heat transport phenomena which can be understood by the large values of the above-mentioned coefficients in comparison to the relaxation collision integral. We have also presented a comparative study of coefficients like the electrical conductivity ($\sigma_{el}$), Hall conductivity ($\sigma_{H}$), thermal conductivity ($\kappa$) and Hall-type thermal conductivity($\kappa_{H}$) in weak and strong magnetic fields in the BGK model approximation. The effects of weak magnetic field and finite chemical potential on the transport coefficients have been explored using a quasiparticle model. Moreover, we have also studied the effects of weak magnetic field and finite chemical potential on Lorenz number, Knudsen number, specific heat, elliptic flow and Wiedemann-Franz law. |
hep-ph/9701267 | null | T. G. Steele, S. Alavian, J. Kwan | Sum-Rule Inequalities and a Toy Model Paradox | 6 pages, RevTeX, figures available upon request to
steelet@sask.usask.ca | Phys.Lett. B392 (1997) 189-192 | 10.1016/S0370-2693(96)01540-7 | null | hep-ph | null | Fundamental inequalities for QCD sum-rules are applied to resolve a paradox
recently encountered in a sum-rule calculation. This paradox was encountered in
a toy model known to be free of resonances that yields an apparent resonance
using a standard sum-rule stability analysis. Application of the inequalities
does not support the existence of a well defined sum-rule calculation, and
shows a strong distinction from typical behaviour in QCD.
| [
{
"created": "Fri, 10 Jan 1997 18:03:36 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Steele",
"T. G.",
""
],
[
"Alavian",
"S.",
""
],
[
"Kwan",
"J.",
""
]
] | Fundamental inequalities for QCD sum-rules are applied to resolve a paradox recently encountered in a sum-rule calculation. This paradox was encountered in a toy model known to be free of resonances that yields an apparent resonance using a standard sum-rule stability analysis. Application of the inequalities does not support the existence of a well defined sum-rule calculation, and shows a strong distinction from typical behaviour in QCD. |
1406.7709 | Tianbo Liu | Tianbo Liu | Quark orbital motions from Wigner distributions | 16 pages, 7 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate quark Wigner distributions in a light-cone spectator model.
Both the scalar and the axial-vector spectators are included. The light-cone
wave functions are derived from effective quark-spectator-nucleon vertex and
then generalized by adjusting the power of energy denominators. The gauge link
is taken into account by introducing relative phases to the light-cone
amplitudes, and the phases are estimated from one gluon exchange interactions.
The mixing distributions, which describe the correlation between transverse
coordinate and transverse momentum and represent quark orbital motions, are
calculated from the Wigner distributions. We find both $u$ quark and $d$ quark
have positive orbital angular momentum in a polarized proton at small $x$
region, but a sign change is observed at large $x$ region for the $d$ quark.
Besides, some model relations between Wigner distributions with different
polarization configurations are found.
| [
{
"created": "Mon, 30 Jun 2014 12:51:02 GMT",
"version": "v1"
}
] | 2014-07-01 | [
[
"Liu",
"Tianbo",
""
]
] | We investigate quark Wigner distributions in a light-cone spectator model. Both the scalar and the axial-vector spectators are included. The light-cone wave functions are derived from effective quark-spectator-nucleon vertex and then generalized by adjusting the power of energy denominators. The gauge link is taken into account by introducing relative phases to the light-cone amplitudes, and the phases are estimated from one gluon exchange interactions. The mixing distributions, which describe the correlation between transverse coordinate and transverse momentum and represent quark orbital motions, are calculated from the Wigner distributions. We find both $u$ quark and $d$ quark have positive orbital angular momentum in a polarized proton at small $x$ region, but a sign change is observed at large $x$ region for the $d$ quark. Besides, some model relations between Wigner distributions with different polarization configurations are found. |
hep-ph/9911459 | Smaragda Lola | John Ellis, M.E.Gomez, G.K.Leontaris, S.Lola and D.V.Nanopoulos | Charged-Lepton-Flavour Violation in the Light of the Super-Kamiokande
Data | 29 pages, 12 figures. References added, typos corrected | Eur.Phys.J.C14:319-334,2000 | 10.1007/s100520000357 | ACT-12/99, CERN-TH/99-237, CTP-TAMU-45/99, FISIST/22-99/CFIF | hep-ph | null | Motivated by the data from Super-Kamiokande and elsewhere indicating
oscillations of atmospheric and solar neutrinos, we study
charged-lepton-flavour violation, in particular the radiative decays mu -> e
gamma and tau -> mu gamma, but also commenting on mu -> 3e and tau -> 3 mu/e
decays, as well as mu - e conversion on nuclei. We first show how the
renormalization group may be used to calculate flavour-violating soft
supersymmetry-breaking masses for charged sleptons and sneutrinos in models
with universal input parameters. Subsequently, we classify possible patterns of
lepton-flavour violation in the context of phenomenological neutrino mass
textures that accommodate the Super-Kamiokande data, giving examples based on
Abelian flavour symmetries. Then we calculate in these examples rates for mu ->
e gamma and tau ->mu gamma, which may be close to the present experimental
upper limits, and show how they may distinguish between the different generic
mixing patterns. The rates are promisingly large when the soft
supersymmetry-breaking mass parameters are chosen to be consistent with the
cosmological relic-density constraints. In addition, we discuss mu -> e
conversion on Titanium, which may also be accessible to future experiments.
| [
{
"created": "Tue, 23 Nov 1999 22:01:29 GMT",
"version": "v1"
},
{
"created": "Sat, 18 Dec 1999 20:59:03 GMT",
"version": "v2"
}
] | 2009-09-11 | [
[
"Ellis",
"John",
""
],
[
"Gomez",
"M. E.",
""
],
[
"Leontaris",
"G. K.",
""
],
[
"Lola",
"S.",
""
],
[
"Nanopoulos",
"D. V.",
""
]
] | Motivated by the data from Super-Kamiokande and elsewhere indicating oscillations of atmospheric and solar neutrinos, we study charged-lepton-flavour violation, in particular the radiative decays mu -> e gamma and tau -> mu gamma, but also commenting on mu -> 3e and tau -> 3 mu/e decays, as well as mu - e conversion on nuclei. We first show how the renormalization group may be used to calculate flavour-violating soft supersymmetry-breaking masses for charged sleptons and sneutrinos in models with universal input parameters. Subsequently, we classify possible patterns of lepton-flavour violation in the context of phenomenological neutrino mass textures that accommodate the Super-Kamiokande data, giving examples based on Abelian flavour symmetries. Then we calculate in these examples rates for mu -> e gamma and tau ->mu gamma, which may be close to the present experimental upper limits, and show how they may distinguish between the different generic mixing patterns. The rates are promisingly large when the soft supersymmetry-breaking mass parameters are chosen to be consistent with the cosmological relic-density constraints. In addition, we discuss mu -> e conversion on Titanium, which may also be accessible to future experiments. |
0805.3804 | Klaus Lichtenegger | Klaus Lichtenegger, Daniel Zwanziger | Nonperturbative contributions to the QCD pressure | 15 pages, 13 figures, uses xcolor.sty; in v2 quality of some figures
has been improved, discussion of other approaches has been extended | Phys.Rev.D78:034038,2008 | 10.1103/PhysRevD.78.034038 | null | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We summarize the most important arguments why a perturbative description of
finite-temperature QCD is unlikely to be possible and review various
well-established approaches to deal with this problem. Then, using a recently
proposed method, we investigate nonperturbative contributions to the QCD
pressure and other observables (like energy, anomaly and bulk viscosity)
obtained by imposing a functional cutoff at the Gribov horizon. Finally, we
discuss how such contributions fit into the picture of consecutive effective
theories, as proposed by Braaten and Nieto, and give an outline of the next
steps necessary to improve this type of calculation.
| [
{
"created": "Mon, 26 May 2008 16:31:26 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Jun 2008 10:35:50 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Lichtenegger",
"Klaus",
""
],
[
"Zwanziger",
"Daniel",
""
]
] | We summarize the most important arguments why a perturbative description of finite-temperature QCD is unlikely to be possible and review various well-established approaches to deal with this problem. Then, using a recently proposed method, we investigate nonperturbative contributions to the QCD pressure and other observables (like energy, anomaly and bulk viscosity) obtained by imposing a functional cutoff at the Gribov horizon. Finally, we discuss how such contributions fit into the picture of consecutive effective theories, as proposed by Braaten and Nieto, and give an outline of the next steps necessary to improve this type of calculation. |
1510.04102 | Georgios Gounaris | G.J. Gounaris and F.M. Renard | Tests of Higgs boson compositeness through the HHH form factor | 13 pages, 10 figures | Phys. Rev. D 93, 093018 (2016) | 10.1103/PhysRevD.93.093018 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show how the $q^2$-dependence of the triple Higgs boson HHH form factor
can reveal the presence of various types of new physics contributions, like new
particles coupled to the Higgs boson or Higgs boson constituents, without
directly observing them. We compare the effect of such new contributions to the
one of higher order SM corrections to the point-like HHH coupling, due to
triangle, 4-leg and s.e. diagrams. We establish simple analytic expressions
describing accurately at high energy these SM corrections, as well as the
examples of new physics contributions.
| [
{
"created": "Wed, 14 Oct 2015 14:05:35 GMT",
"version": "v1"
}
] | 2016-06-01 | [
[
"Gounaris",
"G. J.",
""
],
[
"Renard",
"F. M.",
""
]
] | We show how the $q^2$-dependence of the triple Higgs boson HHH form factor can reveal the presence of various types of new physics contributions, like new particles coupled to the Higgs boson or Higgs boson constituents, without directly observing them. We compare the effect of such new contributions to the one of higher order SM corrections to the point-like HHH coupling, due to triangle, 4-leg and s.e. diagrams. We establish simple analytic expressions describing accurately at high energy these SM corrections, as well as the examples of new physics contributions. |
2302.10449 | Joshua Isaacson | Enrico Bothmann, Taylor Childers, Walter Giele, Florian Herren, Stefan
Hoeche, Joshua Isaacson, Max Knobbe, and Rui Wang | Efficient phase-space generation for hadron collider event simulation | 11 pages, 3 figures | SciPost Phys. 15, 169 (2023) | 10.21468/SciPostPhys.15.4.169 | FERMILAB-PUB-23-032-T, MCnet-23-02 | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We present a simple yet efficient algorithm for phase-space integration at
hadron colliders. Individual mappings consist of a single t-channel combined
with any number of s-channel decays, and are constructed using diagrammatic
information. The factorial growth in the number of channels is tamed by
providing an option to limit the number of s-channel topologies. We provide a
publicly available, parallelized code in C++ and test its performance in
typical LHC scenarios.
| [
{
"created": "Tue, 21 Feb 2023 05:26:59 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Jul 2023 19:54:48 GMT",
"version": "v2"
}
] | 2023-10-18 | [
[
"Bothmann",
"Enrico",
""
],
[
"Childers",
"Taylor",
""
],
[
"Giele",
"Walter",
""
],
[
"Herren",
"Florian",
""
],
[
"Hoeche",
"Stefan",
""
],
[
"Isaacson",
"Joshua",
""
],
[
"Knobbe",
"Max",
""
],
[
... | We present a simple yet efficient algorithm for phase-space integration at hadron colliders. Individual mappings consist of a single t-channel combined with any number of s-channel decays, and are constructed using diagrammatic information. The factorial growth in the number of channels is tamed by providing an option to limit the number of s-channel topologies. We provide a publicly available, parallelized code in C++ and test its performance in typical LHC scenarios. |
hep-ph/9811276 | M. R. Pennington | M.R. Pennington | Glueballs : the Naked Truth | 16 pages, 9 ps/eps figures. Invited talk at the workshop on "Photon
Interactions and Photon Structure", Lund, Sweden (September 1998) to appear
in the Proceedings | null | null | DTP-98/84 | hep-ph | null | The current status of the accepted glueball candidates is reviewed. The
difference between bare and dressed hadrons is emphasised. What two photon
processes, both production and decay, have taught us about these is discussed.
| [
{
"created": "Mon, 9 Nov 1998 12:45:07 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Pennington",
"M. R.",
""
]
] | The current status of the accepted glueball candidates is reviewed. The difference between bare and dressed hadrons is emphasised. What two photon processes, both production and decay, have taught us about these is discussed. |
0912.3942 | Gilly Elor | Gilly Elor, Hock-Seng Goh, Lawrence J. Hall, Piyush Kumar, Yasunori
Nomura | Environmentally Selected WIMP Dark Matter with High-Scale Supersymmetry
Breaking | 27 pages, 8 figures | Phys.Rev.D81:095003,2010 | 10.1103/PhysRevD.81.095003 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the possibility that both the weak scale and the thermal relic
dark matter abundance are environmentally selected in a multiverse. An
underlying supersymmetric theory containing the states of the MSSM and
singlets, with supersymmetry and R symmetry broken at unified scales, has just
two realistic low energy effective theories. One theory, (SM + \tilde{w}), is
the Standard Model augmented only by the wino, having a mass near 3 TeV, and
has a Higgs boson mass in the range of (127 - 142) GeV. The other theory, (SM +
\tilde{h}/\tilde{s}), has Higgsinos and a singlino added to the Standard Model.
The Higgs boson mass depends on the single new Yukawa coupling of the theory,
y, and is near 141 GeV for small y but grows to be as large as 210 GeV as this
new coupling approaches strong coupling at high energies. Much of the parameter
space of this theory will be probed by direct detection searches for dark
matter that push two orders of magnitude below the present bounds; furthermore,
the dark matter mass and cross section on nucleons are correlated with the
Higgs boson mass. The indirect detection signal of monochromatic photons from
the galactic center is computed, and the range of parameters that may be
accessible to LHC searches for trilepton events is explored. Taking a broader
view, allowing the possibility of R symmetry protection to the TeV scale or
axion dark matter, we find four more theories: (SM + axion), two versions of
Split Supersymmetry, and the E-MSSM, where a little supersymmetric hierarchy is
predicted. The special Higgs mass value of (141 \pm 2) GeV appears in symmetry
limits of three of the six theories, (SM + axion), (SM + \tilde{w}) and (SM +
\tilde{h}/\tilde{s}), motivating a comparison of other signals of these three
theories.
| [
{
"created": "Sat, 19 Dec 2009 22:07:26 GMT",
"version": "v1"
}
] | 2010-05-25 | [
[
"Elor",
"Gilly",
""
],
[
"Goh",
"Hock-Seng",
""
],
[
"Hall",
"Lawrence J.",
""
],
[
"Kumar",
"Piyush",
""
],
[
"Nomura",
"Yasunori",
""
]
] | We explore the possibility that both the weak scale and the thermal relic dark matter abundance are environmentally selected in a multiverse. An underlying supersymmetric theory containing the states of the MSSM and singlets, with supersymmetry and R symmetry broken at unified scales, has just two realistic low energy effective theories. One theory, (SM + \tilde{w}), is the Standard Model augmented only by the wino, having a mass near 3 TeV, and has a Higgs boson mass in the range of (127 - 142) GeV. The other theory, (SM + \tilde{h}/\tilde{s}), has Higgsinos and a singlino added to the Standard Model. The Higgs boson mass depends on the single new Yukawa coupling of the theory, y, and is near 141 GeV for small y but grows to be as large as 210 GeV as this new coupling approaches strong coupling at high energies. Much of the parameter space of this theory will be probed by direct detection searches for dark matter that push two orders of magnitude below the present bounds; furthermore, the dark matter mass and cross section on nucleons are correlated with the Higgs boson mass. The indirect detection signal of monochromatic photons from the galactic center is computed, and the range of parameters that may be accessible to LHC searches for trilepton events is explored. Taking a broader view, allowing the possibility of R symmetry protection to the TeV scale or axion dark matter, we find four more theories: (SM + axion), two versions of Split Supersymmetry, and the E-MSSM, where a little supersymmetric hierarchy is predicted. The special Higgs mass value of (141 \pm 2) GeV appears in symmetry limits of three of the six theories, (SM + axion), (SM + \tilde{w}) and (SM + \tilde{h}/\tilde{s}), motivating a comparison of other signals of these three theories. |
hep-ph/0607269 | Valery Lyubovitskij | Amand Faessler, Thomas Gutsche, Sergey Kovalenko, Valery E.
Lyubovitskij | Implications of R-parity violating supersymmetry for atomic and hadronic
EDMs | 11 pages, 1 figure, accepted for publication in Phys. Rev. D | Phys.Rev. D74 (2006) 074013 | 10.1103/PhysRevD.74.074013 | null | hep-ph | null | We calculate the electric dipole moments (EDM) of the neutral Hg(199) atom,
deuteron, nucleons and neutral hyperons Lambda, Sigma(0) and Xi(0) in the
framework of a generic SUSY model without R-parity conservation (RPV SUSY) on
the basis of the SU(3) version of chiral perturbation theory (ChPT). We
consider CP-violation in the hadronic sector induced by the chromoelectric
quark dipole moments and CP-violating 4-quark effective interactions. From the
null experimental results on the neutron and Hg(199) atom EDMs we derive limits
on the imaginary parts of certain products Im(lambda' lambda'*) of the
trilinear RPV-couplings and demonstrate that they are more stringent than those
existing in the literature. Using these limits we give predictions for the EDMs
of neutral hyperons.
We also estimate the prospects of future storage ring experiments on the
deuteron EDM and show that the expected improvement of the above limits in
these experiments may reach several orders of magnitude.
| [
{
"created": "Tue, 25 Jul 2006 08:20:46 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Oct 2006 14:10:23 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Faessler",
"Amand",
""
],
[
"Gutsche",
"Thomas",
""
],
[
"Kovalenko",
"Sergey",
""
],
[
"Lyubovitskij",
"Valery E.",
""
]
] | We calculate the electric dipole moments (EDM) of the neutral Hg(199) atom, deuteron, nucleons and neutral hyperons Lambda, Sigma(0) and Xi(0) in the framework of a generic SUSY model without R-parity conservation (RPV SUSY) on the basis of the SU(3) version of chiral perturbation theory (ChPT). We consider CP-violation in the hadronic sector induced by the chromoelectric quark dipole moments and CP-violating 4-quark effective interactions. From the null experimental results on the neutron and Hg(199) atom EDMs we derive limits on the imaginary parts of certain products Im(lambda' lambda'*) of the trilinear RPV-couplings and demonstrate that they are more stringent than those existing in the literature. Using these limits we give predictions for the EDMs of neutral hyperons. We also estimate the prospects of future storage ring experiments on the deuteron EDM and show that the expected improvement of the above limits in these experiments may reach several orders of magnitude. |
0908.1747 | Abhijit Majumder | Abhijit Majumder | Jet Medium interactions at Quark Matter 09 | 11 pages, 6 figures - To appear in the conference proceedings for
Quark Matter 2009, March 30 - April 4, Knoxville, Tennessee, typos corrected,
references added | Nucl.Phys.A830:875c-882c,2009 | 10.1016/j.nuclphysa.2009.10.129 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The suppression of the yield of high transverse momentum $p_{T}$ hadrons in
heavy-ion collisions, referred to as "jet-quenching", has now developed into a
comprehensive science. Jets are now used as probes of a variety of properties
of the dense medium through which they propagate. Major theoretical
improvements include jet modification in a 3-D fluid dynamical medium, the
first set of in-medium Monte-Carlo implementations, an understanding of
multi-hadron observables and energy flow within perturbative QCD, along with
improvements in the AdS/CFT description of energy loss. On the experimental
side, high statistics data are allowing for the first discriminatory test of
various theoretical models and approximations while the new measurements of
full jet reconstruction pose a challenge to theory.
| [
{
"created": "Wed, 12 Aug 2009 16:31:07 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Oct 2009 18:55:06 GMT",
"version": "v2"
}
] | 2009-11-18 | [
[
"Majumder",
"Abhijit",
""
]
] | The suppression of the yield of high transverse momentum $p_{T}$ hadrons in heavy-ion collisions, referred to as "jet-quenching", has now developed into a comprehensive science. Jets are now used as probes of a variety of properties of the dense medium through which they propagate. Major theoretical improvements include jet modification in a 3-D fluid dynamical medium, the first set of in-medium Monte-Carlo implementations, an understanding of multi-hadron observables and energy flow within perturbative QCD, along with improvements in the AdS/CFT description of energy loss. On the experimental side, high statistics data are allowing for the first discriminatory test of various theoretical models and approximations while the new measurements of full jet reconstruction pose a challenge to theory. |
hep-ph/9403276 | Davison Soper | Arjun Berera and Davison E. Soper | Diffractive jet production in a simple model with applications to HERA | 23 pages, REVTeX 3.0 with 8 postscript figures compressed with
uufiles, OITS 536 and AZPH-TH/94-02 | Phys.Rev. D50 (1994) 4328-4340 | 10.1103/PhysRevD.50.4328 | null | hep-ph | null | In diffractive jet production, two high energy hadrons A and B collide and
produce high transverse momentum jets, while hadron A is diffractively
scattered. Ingelman and Schlein predicted this phenomenon. In their model, part
of the longitudinal momentum transferred from hadron A is delivered to the jet
system, part is lost. Lossless diffractive jet production, in which all of this
longitudinal momentum is delivered to the jet system, has been discussed by
Collins, Frankfurt, and Strikman. We study the structure of lossless
diffractive jet production in a simple model. The model suggests that the
phenomenon can be probed experimentally at HERA, with A being a proton and B
being a bremsstrahlung photon with virtuality $Q^2$. Lossless events should be
present for small $Q^2$, but not for $Q^2$ larger than $1/R_{\rm P}^2$, where
$R_{\rm P}$ is a characteristic size of the pomeron.
| [
{
"created": "Fri, 11 Mar 1994 20:26:49 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Berera",
"Arjun",
""
],
[
"Soper",
"Davison E.",
""
]
] | In diffractive jet production, two high energy hadrons A and B collide and produce high transverse momentum jets, while hadron A is diffractively scattered. Ingelman and Schlein predicted this phenomenon. In their model, part of the longitudinal momentum transferred from hadron A is delivered to the jet system, part is lost. Lossless diffractive jet production, in which all of this longitudinal momentum is delivered to the jet system, has been discussed by Collins, Frankfurt, and Strikman. We study the structure of lossless diffractive jet production in a simple model. The model suggests that the phenomenon can be probed experimentally at HERA, with A being a proton and B being a bremsstrahlung photon with virtuality $Q^2$. Lossless events should be present for small $Q^2$, but not for $Q^2$ larger than $1/R_{\rm P}^2$, where $R_{\rm P}$ is a characteristic size of the pomeron. |
hep-ph/9601344 | Sergey Nedelko | Ja.V. Burdanov, G.V. Efimov, S.N. Nedelko, S.A. Solunin | Meson masses within the model of induced nonlocal quark currents | 31 pages, LaTex | Phys.Rev.D54:4483-4498,1996 | 10.1103/PhysRevD.54.4483 | null | hep-ph | null | The model of induced quark currents formulated in our recent paper (Phys.
Rev. D51, 176) is developed. The model being a kind of nonlocal extension of
the bosonization procedure is based on the hypothesis that the QCD vacuum is
realized by the (anti-)self-dual homogeneous gluon field. This vacuum field
provides the analytical quark confinement. It is shown that a particular form
of nonlocality of the quark and gluon propagators determined by the vacuum
field, an interaction of quark spin with the vacuum gluon field and a
localization of meson field at the center of masses of two quarks can explain
the distinctive features of meson spectrum: Regge trajectories of radial and
orbital excitations, mass splitting between pseudoscalar and vector mesons, the
asymptotic mass formulas in the heavy quark limit: $M_{Q\bar Q}\to 2m_Q$ for
quarkonia and $M_{Q\bar q}\to m_Q$ for heavy-light mesons. With a minimal set
of parameters (quark masses, vacuum field strength and the quark-gluon coupling
constant) the model describes to within ten percent inaccuracy the masses and
weak decay constants of mesons from all qualitatively different regions of the
spectrum.
| [
{
"created": "Fri, 26 Jan 1996 16:39:46 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Burdanov",
"Ja. V.",
""
],
[
"Efimov",
"G. V.",
""
],
[
"Nedelko",
"S. N.",
""
],
[
"Solunin",
"S. A.",
""
]
] | The model of induced quark currents formulated in our recent paper (Phys. Rev. D51, 176) is developed. The model being a kind of nonlocal extension of the bosonization procedure is based on the hypothesis that the QCD vacuum is realized by the (anti-)self-dual homogeneous gluon field. This vacuum field provides the analytical quark confinement. It is shown that a particular form of nonlocality of the quark and gluon propagators determined by the vacuum field, an interaction of quark spin with the vacuum gluon field and a localization of meson field at the center of masses of two quarks can explain the distinctive features of meson spectrum: Regge trajectories of radial and orbital excitations, mass splitting between pseudoscalar and vector mesons, the asymptotic mass formulas in the heavy quark limit: $M_{Q\bar Q}\to 2m_Q$ for quarkonia and $M_{Q\bar q}\to m_Q$ for heavy-light mesons. With a minimal set of parameters (quark masses, vacuum field strength and the quark-gluon coupling constant) the model describes to within ten percent inaccuracy the masses and weak decay constants of mesons from all qualitatively different regions of the spectrum. |
hep-ph/0207136 | Marc Sher | Marc Sher (William and Mary) | Tau Decays to Mu + Eta in Supersymmetric Models | 5 pages, 2 figures. Paragraph about CLEO measurements added. Version
to appear in PRD | Phys.Rev. D66 (2002) 057301 | 10.1103/PhysRevD.66.057301 | null | hep-ph | null | The existence of large \nu_\mu-\nu_\tau mixing suggests the likelihood of
large smuon-stau mixing in supersymmetric models, leading to \mu and \tau
number violation. In addition to interesting signatures in slepton and
neutralino production and decay, this will lead to rare \tau decays, such as
\tau --> mu \gamma. Recently, it has been pointed out that the \tau --> 3\mu
branching ratio could be substantial in the large \tan\beta region of parameter
space, due to an induced \mu-\tau-Higgs vertex. In this paper, another
signature, \tau --> \mu \eta is considered. In the large \tan\beta region, it
is shown that the branching ratio of \tau --> \mu \eta is 8.4 times the
branching ratio of \tau --> 3\mu, independent of any unknown parameters, and it
will thus give the most stringent bound on Higgs-mediated lepton flavor
violation, and may provide its first signature. In the other regions of
parameter space, where \tau --> \mu \gamma is the most prominent decay, the
branching ratio for \tau --> \mu \eta is always substantially lower.
| [
{
"created": "Wed, 10 Jul 2002 17:48:15 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Jul 2002 18:32:24 GMT",
"version": "v2"
},
{
"created": "Wed, 31 Jul 2002 15:43:19 GMT",
"version": "v3"
}
] | 2009-11-07 | [
[
"Sher",
"Marc",
"",
"William and Mary"
]
] | The existence of large \nu_\mu-\nu_\tau mixing suggests the likelihood of large smuon-stau mixing in supersymmetric models, leading to \mu and \tau number violation. In addition to interesting signatures in slepton and neutralino production and decay, this will lead to rare \tau decays, such as \tau --> mu \gamma. Recently, it has been pointed out that the \tau --> 3\mu branching ratio could be substantial in the large \tan\beta region of parameter space, due to an induced \mu-\tau-Higgs vertex. In this paper, another signature, \tau --> \mu \eta is considered. In the large \tan\beta region, it is shown that the branching ratio of \tau --> \mu \eta is 8.4 times the branching ratio of \tau --> 3\mu, independent of any unknown parameters, and it will thus give the most stringent bound on Higgs-mediated lepton flavor violation, and may provide its first signature. In the other regions of parameter space, where \tau --> \mu \gamma is the most prominent decay, the branching ratio for \tau --> \mu \eta is always substantially lower. |
0807.3090 | Fyodor Tkachov | F. V. Tkachov | A comment on the LLA method, the kT jet algorithm and the BFKL theory | 6 pages; published in: "Hadron structure and QCD: from low to high
energies": HSQCD 2008, Gatchina, Russia, June 30-July 4, 2008. Gatchina :
Petersburg nuclear physics inst. of Russian acad. sci., 2010. ISBN
978-5-86763-255-7 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The leading logarithmic approximation method fails to yield the correct
asymptotic behavior in some realistic situations: inclusion of the beta-terms
to which the LLA method is insensitive may change a power growth to merely
logarithmic. The results of [hep-ph/0101058] indicate that the problem of
large-s behavior of total cross sections belongs to this class. Similarly, a
reference to the LLA method cannot be sufficient to justify constructions such
as the kT jet algorithm.
| [
{
"created": "Sat, 19 Jul 2008 13:42:51 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Feb 2013 10:02:07 GMT",
"version": "v2"
}
] | 2013-02-08 | [
[
"Tkachov",
"F. V.",
""
]
] | The leading logarithmic approximation method fails to yield the correct asymptotic behavior in some realistic situations: inclusion of the beta-terms to which the LLA method is insensitive may change a power growth to merely logarithmic. The results of [hep-ph/0101058] indicate that the problem of large-s behavior of total cross sections belongs to this class. Similarly, a reference to the LLA method cannot be sufficient to justify constructions such as the kT jet algorithm. |
0905.3234 | T. Lappi | F. Gelis, T. Lappi, L. McLerran | Glittering Glasmas | 12 pages, 7 figures, uses elsarticle.cls V2: added references V3:
typo corrections, published in Nucl. Phys. A | Nucl.Phys.A828:149-160,2009 | 10.1016/j.nuclphysa.2009.07.004 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We compute the production of gluons from Glasma color flux tubes. We
calculate the probability distribution of gluon multiplicities arising from the
distribution of color electric and color magnetic flux tubes found in the
Glasma. We show that the result corresponds to the negative binomial
probability distribution observed in experiments. The parameter k that
characterizes this distribution is proportional to the number of colors N_c^2-1
and to the number of flux tubes. For one gluon color and one flux tube, the
multiplicity distribution is close to a Bose-Einstein distribution. We call
this decay process "Glitter", a term that is explained below.
| [
{
"created": "Wed, 20 May 2009 07:50:51 GMT",
"version": "v1"
},
{
"created": "Tue, 26 May 2009 07:37:54 GMT",
"version": "v2"
},
{
"created": "Tue, 28 Jul 2009 10:51:03 GMT",
"version": "v3"
}
] | 2010-05-28 | [
[
"Gelis",
"F.",
""
],
[
"Lappi",
"T.",
""
],
[
"McLerran",
"L.",
""
]
] | We compute the production of gluons from Glasma color flux tubes. We calculate the probability distribution of gluon multiplicities arising from the distribution of color electric and color magnetic flux tubes found in the Glasma. We show that the result corresponds to the negative binomial probability distribution observed in experiments. The parameter k that characterizes this distribution is proportional to the number of colors N_c^2-1 and to the number of flux tubes. For one gluon color and one flux tube, the multiplicity distribution is close to a Bose-Einstein distribution. We call this decay process "Glitter", a term that is explained below. |
1811.03256 | Wen-Chen Chang | Wen-Chen Chang, Randall Evan McClellan, Jen-Chieh Peng and Oleg
Teryaev | Lepton angular distributions of fixed-target Drell-Yan experiments in
perturbative QCD and a geometric approach | published version, two-column format, 10 pages, 14 figures | Phys. Rev. D 99, 014032 (2019) | 10.1103/PhysRevD.99.014032 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The lepton angular distributions of the Drell-Yan process in fixed-target
experiments are investigated by NLO and NNLO perturbative QCD. We present the
calculated angular parameters $\lambda$, $\mu$, $\nu$ and the degree of
violation of the Lam-Tung relation, $1-\lambda-2\nu$, for the NA10, E615 and
E866 experiments. Predictions for the ongoing COMPASS and SeaQuest experiments
are also presented. The transverse momentum ($q_T$) distributions of $\lambda$
and $\nu$ show a clear dependence on the dimuon mass ($Q$) while those of $\mu$
have a strong rapidity ($x_F$) dependence. Furthermore, $\lambda$ and $\nu$ are
found to scale with $q_T/Q$. These salient features could be qualitatively
understood by a geometric approach where the lepton angular distribution
parameters are expressed in terms of the polar and azimuthal angles of the
"natural axis" in the dilepton rest frame.
| [
{
"created": "Thu, 8 Nov 2018 04:00:16 GMT",
"version": "v1"
},
{
"created": "Fri, 25 Jan 2019 02:26:22 GMT",
"version": "v2"
}
] | 2019-01-28 | [
[
"Chang",
"Wen-Chen",
""
],
[
"McClellan",
"Randall Evan",
""
],
[
"Peng",
"Jen-Chieh",
""
],
[
"Teryaev",
"Oleg",
""
]
] | The lepton angular distributions of the Drell-Yan process in fixed-target experiments are investigated by NLO and NNLO perturbative QCD. We present the calculated angular parameters $\lambda$, $\mu$, $\nu$ and the degree of violation of the Lam-Tung relation, $1-\lambda-2\nu$, for the NA10, E615 and E866 experiments. Predictions for the ongoing COMPASS and SeaQuest experiments are also presented. The transverse momentum ($q_T$) distributions of $\lambda$ and $\nu$ show a clear dependence on the dimuon mass ($Q$) while those of $\mu$ have a strong rapidity ($x_F$) dependence. Furthermore, $\lambda$ and $\nu$ are found to scale with $q_T/Q$. These salient features could be qualitatively understood by a geometric approach where the lepton angular distribution parameters are expressed in terms of the polar and azimuthal angles of the "natural axis" in the dilepton rest frame. |
2403.18582 | Caio Daumann | Caio Cesar Daumann, Mauro Donega, Johannes Erdmann, Massimiliano
Galli, Jan Lukas Sp\"ah, Davide Valsecchi | One flow to correct them all: improving simulations in high-energy
physics with a single normalising flow and a switch | 19 pages, 12 figures | null | null | null | hep-ph cs.LG hep-ex physics.data-an | http://creativecommons.org/licenses/by/4.0/ | Simulated events are key ingredients in almost all high-energy physics
analyses. However, imperfections in the simulation can lead to sizeable
differences between the observed data and simulated events. The effects of such
mismodelling on relevant observables must be corrected either effectively via
scale factors, with weights or by modifying the distributions of the
observables and their correlations. We introduce a correction method that
transforms one multidimensional distribution (simulation) into another one
(data) using a simple architecture based on a single normalising flow with a
boolean condition. We demonstrate the effectiveness of the method on a
physics-inspired toy dataset with non-trivial mismodelling of several
observables and their correlations.
| [
{
"created": "Wed, 27 Mar 2024 14:03:41 GMT",
"version": "v1"
}
] | 2024-03-28 | [
[
"Daumann",
"Caio Cesar",
""
],
[
"Donega",
"Mauro",
""
],
[
"Erdmann",
"Johannes",
""
],
[
"Galli",
"Massimiliano",
""
],
[
"Späh",
"Jan Lukas",
""
],
[
"Valsecchi",
"Davide",
""
]
] | Simulated events are key ingredients in almost all high-energy physics analyses. However, imperfections in the simulation can lead to sizeable differences between the observed data and simulated events. The effects of such mismodelling on relevant observables must be corrected either effectively via scale factors, with weights or by modifying the distributions of the observables and their correlations. We introduce a correction method that transforms one multidimensional distribution (simulation) into another one (data) using a simple architecture based on a single normalising flow with a boolean condition. We demonstrate the effectiveness of the method on a physics-inspired toy dataset with non-trivial mismodelling of several observables and their correlations. |
hep-ph/0108073 | Concepcion Gonzalez-Garcia | M.C. Gonzalez-Garcia, M. Maltoni, and C.Pe\~na-Garay | Update on Solar and Atmospheric Four-Neutrino Oscillations | Expanded version of the proceedings for the talk presented at the EPS
Conference, Budapest, Hungary, July 2001. Update of hep-ph/0105269 including
SNO results. Figure 7 centered and caption corrected | null | 10.1016/S0920-5632(01)01064-7 | CERN-TH/2001-214, IFIC-01-43 | hep-ph | null | In this talk we present the update (including the recent SNO results) of our
analysis of the neutrino oscillation solutions of the solar and atmospheric
neutrino problems in the framework of four-neutrino mixing where a sterile
neutrino is added to the three standard ones and the mass spectra present two
separated doublets. Such scenarios allow for simultaneous transitions of solar
$\nu_e$, as well as atmospheric $\nu_\mu$, into a combination of active and
sterile neutrinos. We evaluate the allowed active-sterile admixture in both
solar and atmospheric oscillations from the combined analysis. Our results show
that, although the Super-Kamiokande data disfavour both the pure
$\nu_\mu\to\nu_s$ atmospheric channel and, in combination with SNO, the pure
$\nu_e\to\nu_s$ solar channel, the result from the combined analysis still
favours close-to-pure active and sterile oscillations and disfavours
oscillations into a near-maximal active-sterile admixture.
| [
{
"created": "Wed, 8 Aug 2001 09:28:31 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Aug 2001 14:25:58 GMT",
"version": "v2"
}
] | 2019-08-17 | [
[
"Gonzalez-Garcia",
"M. C.",
""
],
[
"Maltoni",
"M.",
""
],
[
"Peña-Garay",
"C.",
""
]
] | In this talk we present the update (including the recent SNO results) of our analysis of the neutrino oscillation solutions of the solar and atmospheric neutrino problems in the framework of four-neutrino mixing where a sterile neutrino is added to the three standard ones and the mass spectra present two separated doublets. Such scenarios allow for simultaneous transitions of solar $\nu_e$, as well as atmospheric $\nu_\mu$, into a combination of active and sterile neutrinos. We evaluate the allowed active-sterile admixture in both solar and atmospheric oscillations from the combined analysis. Our results show that, although the Super-Kamiokande data disfavour both the pure $\nu_\mu\to\nu_s$ atmospheric channel and, in combination with SNO, the pure $\nu_e\to\nu_s$ solar channel, the result from the combined analysis still favours close-to-pure active and sterile oscillations and disfavours oscillations into a near-maximal active-sterile admixture. |
hep-ph/9603437 | Hanns Stremnitzer | H. Stremnitzer (Univ. of Vienna) | Need for Two Vectorlike Families in SUSY Composite Models | 6 pages, LaTeX, no macros needed | null | null | UMThPh-1996-24; Proceedings of Hadron Structure 96 Meeting, Stara
Lesna, Slovakia | hep-ph | null | Within the context of a viable and economical SUSY preon model, two
vector--like families $Q_{L,R} = (U,D,N,E)_{L,R}$ and $Q^\prime_{L,R} =
(U^\prime,D^\prime,N^\prime,E^\prime)_{L,R}$ with masses of order 1 TeV, one of
which is a doublet of $SU(2)_L$ and the other a doublet of $SU(2)_R$, have been
predicted to exist together with the three observed chiral families. The
existence of these two vector--like families turns out to be crucial especially
for an explanation of the inter--family mass--hierarchy and therefore for the
SUSY preon model itself. This paper is devoted to a detailed study of the
expected masses, mixings and decay modes of the vector--like fermions.
Including QCD renormalization--effects, the masses of the vector--like quarks
are expected to lie in the range of 500 GeV to about 2.5 TeV, while those of
the vector--like leptons are expected to be in the range of 200 GeV to 1 TeV.
| [
{
"created": "Fri, 29 Mar 1996 15:15:31 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Stremnitzer",
"H.",
"",
"Univ. of Vienna"
]
] | Within the context of a viable and economical SUSY preon model, two vector--like families $Q_{L,R} = (U,D,N,E)_{L,R}$ and $Q^\prime_{L,R} = (U^\prime,D^\prime,N^\prime,E^\prime)_{L,R}$ with masses of order 1 TeV, one of which is a doublet of $SU(2)_L$ and the other a doublet of $SU(2)_R$, have been predicted to exist together with the three observed chiral families. The existence of these two vector--like families turns out to be crucial especially for an explanation of the inter--family mass--hierarchy and therefore for the SUSY preon model itself. This paper is devoted to a detailed study of the expected masses, mixings and decay modes of the vector--like fermions. Including QCD renormalization--effects, the masses of the vector--like quarks are expected to lie in the range of 500 GeV to about 2.5 TeV, while those of the vector--like leptons are expected to be in the range of 200 GeV to 1 TeV. |
2312.10927 | Kentaro Nishimura | Minoru Eto, Kentaro Nishimura, and Muneto Nitta | Non-Abelian chiral soliton lattice in rotating QCD matter:
Nambu-Goldstone and excited modes | 32 pages, 11 figures | null | null | YGHP-23-06 | hep-ph hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The ground state of QCD with two flavors at a finite baryon chemical
potential under rapid rotation is a chiral soliton lattice (CSL) of the $\eta$
meson, consisting of a stack of sine-Gordon solitons carrying a baryon number,
due to the anomalous coupling of the $\eta$ meson to the rotation. In a large
parameter region, the ground state becomes a non-Abelian CSL, in which due to
the neutral pion condensation each $\eta$ soliton decays into a pair of
non-Abelian sine-Gordon solitons carrying $S^2$ moduli originated from
Nambu-Goldstone (NG) modes localized around it, corresponding to the
spontaneously broken vector symmetry SU$(2)_{\rm V}$. There, the $S^2$ modes of
neighboring solitons are anti-aligned, and these modes should propagate in the
transverse direction of the lattice due to the interaction between the $S^2$
modes of neighboring solitons. In this paper, we calculate excitations
including gapless NG modes and excited modes around non-Abelian and Abelian
($\eta$) CSLs, and find three gapless NG modes with linear dispersion relations
(type-A NG modes): two isospinons ($S^2$ modes) and a phonon corresponding to
the spontaneously broken vector SU$(2)_{\rm V}$ and translational symmetries
around the non-Abelian CSL, respectively, and only a phonon for the Abelian CSL
because of the recovering SU$(2)_{\rm V}$. We also find in the deconfined phase
that the dispersion relation of the isospinons becomes of the Dirac type, {\it
i.~e.~} linear even at large momentum.
| [
{
"created": "Mon, 18 Dec 2023 04:36:13 GMT",
"version": "v1"
}
] | 2023-12-19 | [
[
"Eto",
"Minoru",
""
],
[
"Nishimura",
"Kentaro",
""
],
[
"Nitta",
"Muneto",
""
]
] | The ground state of QCD with two flavors at a finite baryon chemical potential under rapid rotation is a chiral soliton lattice (CSL) of the $\eta$ meson, consisting of a stack of sine-Gordon solitons carrying a baryon number, due to the anomalous coupling of the $\eta$ meson to the rotation. In a large parameter region, the ground state becomes a non-Abelian CSL, in which due to the neutral pion condensation each $\eta$ soliton decays into a pair of non-Abelian sine-Gordon solitons carrying $S^2$ moduli originated from Nambu-Goldstone (NG) modes localized around it, corresponding to the spontaneously broken vector symmetry SU$(2)_{\rm V}$. There, the $S^2$ modes of neighboring solitons are anti-aligned, and these modes should propagate in the transverse direction of the lattice due to the interaction between the $S^2$ modes of neighboring solitons. In this paper, we calculate excitations including gapless NG modes and excited modes around non-Abelian and Abelian ($\eta$) CSLs, and find three gapless NG modes with linear dispersion relations (type-A NG modes): two isospinons ($S^2$ modes) and a phonon corresponding to the spontaneously broken vector SU$(2)_{\rm V}$ and translational symmetries around the non-Abelian CSL, respectively, and only a phonon for the Abelian CSL because of the recovering SU$(2)_{\rm V}$. We also find in the deconfined phase that the dispersion relation of the isospinons becomes of the Dirac type, {\it i.~e.~} linear even at large momentum. |
1604.02299 | Matthew Wing | I. Abt, A.M. Cooper-Sarkar, B.Foster, V. Myronenko, K. Wichmann, M.
Wing | Study of HERA ep Data at Low Q^2 and Low x_Bj and the Need for
Higher-Twist Corrections to Standard pQCD Fits | 24 pages, 14 figures, updated version contains small changes made
during the review process | Phys. Rev. D 94, 034032 (2016) | 10.1103/PhysRevD.94.034032 | DESY-16-064 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A detailed comparison of HERA data at low Bjorken-$x$ and low
four-momentum-transfer squared, $Q^2$, with predictions based on $\ln{Q^2}$
evolution (DGLAP) in perturbative Quantum Chromo Dynamics suggests inadequacies
of this framework. The standard DGLAP evolution was augmented by including an
additional higher-twist term in the description of the longitudinal structure
function, $F_{\rm L}$. This additional term, $F_{\rm L}~A_{\rm L}^{\rm
HT}/Q^2$, improves the description of the reduced cross sections significantly.
The resulting predictions for $F_{\rm L}$ suggest that further corrections are
required for $Q^2$ less than about 2 GeV$^2$.
| [
{
"created": "Fri, 8 Apr 2016 10:42:22 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Oct 2016 10:24:47 GMT",
"version": "v2"
}
] | 2016-10-12 | [
[
"Abt",
"I.",
""
],
[
"Cooper-Sarkar",
"A. M.",
""
],
[
"Foster",
"B.",
""
],
[
"Myronenko",
"V.",
""
],
[
"Wichmann",
"K.",
""
],
[
"Wing",
"M.",
""
]
] | A detailed comparison of HERA data at low Bjorken-$x$ and low four-momentum-transfer squared, $Q^2$, with predictions based on $\ln{Q^2}$ evolution (DGLAP) in perturbative Quantum Chromo Dynamics suggests inadequacies of this framework. The standard DGLAP evolution was augmented by including an additional higher-twist term in the description of the longitudinal structure function, $F_{\rm L}$. This additional term, $F_{\rm L}~A_{\rm L}^{\rm HT}/Q^2$, improves the description of the reduced cross sections significantly. The resulting predictions for $F_{\rm L}$ suggest that further corrections are required for $Q^2$ less than about 2 GeV$^2$. |
2010.15546 | Stephane Munier | Anh Dung Le, Alfred H. Mueller, St\'ephane Munier | Nuclear scattering configurations of onia in different frames | 24 pages, 4 figures. v2: minor corrections, reference added | Phys. Rev. D 103, 054031 (2021) | 10.1103/PhysRevD.103.054031 | null | hep-ph cond-mat.stat-mech | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the scattering of a small onium off a large nucleus at high center-of-mass
energies, when the parameters are set in such a way that the cross section at
fixed impact parameter is small, events are triggered by rare partonic
fluctuations of the onium, which are very deformed with respect to typical
configurations. Using the color dipole picture of high-energy interactions in
quantum chromodynamics, in which the quantum states of the onium are
represented by sets of dipoles generated by a branching process, we describe
the typical scattering configurations as seen from different reference frames,
from the restframe of the nucleus to frames in which the rapidity is shared
between the projectile onium and the nucleus. We show that taking advantage of
the freedom to select a frame in the latter class makes possible to derive
complete asymptotic expressions for some boost-invariant quantities, beyond the
total cross section, from a procedure which leverages the limited available
knowledge on the properties of the solutions to the Balitsky-Kovchegov equation
that governs the rapidity-dependence of total cross sections. We obtain in this
way an analytic expression for the rapidity-distribution of the first branching
of the slowest parent dipole of the set of those which scatter. This
distribution provides an estimator of the correlations of the interacting
dipoles, and is also known to be related to the rapidity-gap distribution in
diffractive dissociation, an observable measurable at a future electron-ion
collider. Furthermore, our result may be formulated as a more general
conjecture, that we expect to hold true for any one-dimensional branching
random walk model, on the branching time of the most recent common ancestor of
all the particles that end up to the right of a given position.
| [
{
"created": "Thu, 29 Oct 2020 13:25:09 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Mar 2021 17:34:12 GMT",
"version": "v2"
}
] | 2021-03-31 | [
[
"Le",
"Anh Dung",
""
],
[
"Mueller",
"Alfred H.",
""
],
[
"Munier",
"Stéphane",
""
]
] | In the scattering of a small onium off a large nucleus at high center-of-mass energies, when the parameters are set in such a way that the cross section at fixed impact parameter is small, events are triggered by rare partonic fluctuations of the onium, which are very deformed with respect to typical configurations. Using the color dipole picture of high-energy interactions in quantum chromodynamics, in which the quantum states of the onium are represented by sets of dipoles generated by a branching process, we describe the typical scattering configurations as seen from different reference frames, from the restframe of the nucleus to frames in which the rapidity is shared between the projectile onium and the nucleus. We show that taking advantage of the freedom to select a frame in the latter class makes possible to derive complete asymptotic expressions for some boost-invariant quantities, beyond the total cross section, from a procedure which leverages the limited available knowledge on the properties of the solutions to the Balitsky-Kovchegov equation that governs the rapidity-dependence of total cross sections. We obtain in this way an analytic expression for the rapidity-distribution of the first branching of the slowest parent dipole of the set of those which scatter. This distribution provides an estimator of the correlations of the interacting dipoles, and is also known to be related to the rapidity-gap distribution in diffractive dissociation, an observable measurable at a future electron-ion collider. Furthermore, our result may be formulated as a more general conjecture, that we expect to hold true for any one-dimensional branching random walk model, on the branching time of the most recent common ancestor of all the particles that end up to the right of a given position. |
1103.1888 | Jonathan Gaunt | Jonathan R. Gaunt, W. James Stirling | Double Parton Scattering Singularity in One-Loop Integrals | 29 pages, 8 figures. Minor corrections and clarifications added.
Version accepted for publication in JHEP | JHEP 1106:048,2011 | 10.1007/JHEP06(2011)048 | Cavendish-HEP-11/02 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a detailed study of the double parton scattering (DPS)
singularity, which is a specific type of Landau singularity that can occur in
certain one-loop graphs in theories with massless particles. A simple formula
for the DPS singular part of a four-point diagram with arbitrary
internal/external particles is derived in terms of the transverse momentum
integral of a product of light cone wavefunctions with tree-level matrix
elements. This is used to reproduce and explain some results for DPS
singularities in box integrals that have been obtained using traditional loop
integration techniques. The formula can be straightforwardly generalised to
calculate the DPS singularity in loops with an arbitrary number of external
particles. We use the generalised version to explain why the specific MHV and
NMHV six-photon amplitudes often studied by the NLO multileg community are not
divergent at the DPS singular point, and point out that whilst all NMHV
amplitudes are always finite, certain MHV amplitudes do contain a DPS
divergence. It is shown that our framework for calculating DPS divergences in
loop diagrams is entirely consistent with the `two-parton GPD' framework of
Diehl and Schafer for calculating proton-proton DPS cross sections, but is
inconsistent with the `double PDF' framework of Snigirev.
| [
{
"created": "Wed, 9 Mar 2011 21:12:45 GMT",
"version": "v1"
},
{
"created": "Thu, 5 May 2011 10:02:39 GMT",
"version": "v2"
}
] | 2011-06-21 | [
[
"Gaunt",
"Jonathan R.",
""
],
[
"Stirling",
"W. James",
""
]
] | We present a detailed study of the double parton scattering (DPS) singularity, which is a specific type of Landau singularity that can occur in certain one-loop graphs in theories with massless particles. A simple formula for the DPS singular part of a four-point diagram with arbitrary internal/external particles is derived in terms of the transverse momentum integral of a product of light cone wavefunctions with tree-level matrix elements. This is used to reproduce and explain some results for DPS singularities in box integrals that have been obtained using traditional loop integration techniques. The formula can be straightforwardly generalised to calculate the DPS singularity in loops with an arbitrary number of external particles. We use the generalised version to explain why the specific MHV and NMHV six-photon amplitudes often studied by the NLO multileg community are not divergent at the DPS singular point, and point out that whilst all NMHV amplitudes are always finite, certain MHV amplitudes do contain a DPS divergence. It is shown that our framework for calculating DPS divergences in loop diagrams is entirely consistent with the `two-parton GPD' framework of Diehl and Schafer for calculating proton-proton DPS cross sections, but is inconsistent with the `double PDF' framework of Snigirev. |
hep-ph/0302231 | Edward Shuryak | Edward Shuryak and Ismail Zahed | Semiclassical Double-Pomeron Production of Glueballs and $\eta'$ | null | Phys.Rev. D68 (2003) 034001 | 10.1103/PhysRevD.68.034001 | null | hep-ph | null | A semiclassical theory of high energy scattering based on interrupted
tunneling (instantons) or QCD sphaleron production has been recently developed
to describe the growing hadronic cross section and properties of the soft
Pomeron. In this work we address double-pomeron processes in this framework for
the first time. We specifically derive the cross section for central production
of parity even and odd clusters, scalar and pseudoscalar glueballs, and $\eta'$
in parton-parton scattering at high energy. We show that the specific
dependence of the production cross section on all its kinematical variables
compares favorably with the UA8 data on inclusive cluster production, as well
as the WA102 data on exclusive central production of scalar glueball and
$\eta'$, in double-pomeron exchange $pp$ scattering. The magnitude of the cross
section and its dependece on kinematic variables is correct, explaining in
particular a large deviation from the Pomeron factorization at cluster masses
in the range $M_X<8$ GeV reported by UA8.
| [
{
"created": "Tue, 25 Feb 2003 17:52:02 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Shuryak",
"Edward",
""
],
[
"Zahed",
"Ismail",
""
]
] | A semiclassical theory of high energy scattering based on interrupted tunneling (instantons) or QCD sphaleron production has been recently developed to describe the growing hadronic cross section and properties of the soft Pomeron. In this work we address double-pomeron processes in this framework for the first time. We specifically derive the cross section for central production of parity even and odd clusters, scalar and pseudoscalar glueballs, and $\eta'$ in parton-parton scattering at high energy. We show that the specific dependence of the production cross section on all its kinematical variables compares favorably with the UA8 data on inclusive cluster production, as well as the WA102 data on exclusive central production of scalar glueball and $\eta'$, in double-pomeron exchange $pp$ scattering. The magnitude of the cross section and its dependece on kinematic variables is correct, explaining in particular a large deviation from the Pomeron factorization at cluster masses in the range $M_X<8$ GeV reported by UA8. |
2107.10688 | Ansgar Denner | Ansgar Denner, Robert Franken, Mathieu Pellen, Timo Schmidt | Full NLO predictions for vector-boson scattering into Z bosons and its
irreducible background at the LHC | 25 pages, 25 pdf figure files, minor corrections w.r.t. v1, version
to appear in JHEP | null | 10.1007/JHEP10(2021)228 | FR-PHENO-2021-08, VBSCAN-PUB-08-21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Vector-boson scattering into two Z bosons at the LHC is a key channel for the
exploration of the electroweak sector of the Standard Model. It allows for the
full reconstruction of the scattering process but at the price of a huge
irreducible background. For the first time, we present full
next-to-leading-order predictions for $pp \to e^+e^-\mu^+\mu^-jj+X$ including
all electroweak and QCD contributions for vector-boson scattering signal and
irreducible background. The results are presented in the form of cross sections
and differential distributions. A particular emphasis is put on the newly
computed $O(\alpha_s^2 \alpha^5)$ corrections.
| [
{
"created": "Thu, 22 Jul 2021 13:51:54 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Oct 2021 08:41:20 GMT",
"version": "v2"
}
] | 2021-11-17 | [
[
"Denner",
"Ansgar",
""
],
[
"Franken",
"Robert",
""
],
[
"Pellen",
"Mathieu",
""
],
[
"Schmidt",
"Timo",
""
]
] | Vector-boson scattering into two Z bosons at the LHC is a key channel for the exploration of the electroweak sector of the Standard Model. It allows for the full reconstruction of the scattering process but at the price of a huge irreducible background. For the first time, we present full next-to-leading-order predictions for $pp \to e^+e^-\mu^+\mu^-jj+X$ including all electroweak and QCD contributions for vector-boson scattering signal and irreducible background. The results are presented in the form of cross sections and differential distributions. A particular emphasis is put on the newly computed $O(\alpha_s^2 \alpha^5)$ corrections. |
2112.12724 | Guilherme Guedes | Mikael Chala, \'Alvaro D\'iaz-Carmona and Guilherme Guedes | A Green's basis for the bosonic SMEFT to dimension 8 | 32 pages, 4 tables | null | 10.1007/JHEP05(2022)138 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We present a basis of dimension-eight Green's functions involving Standard
Model (SM) bosonic fields, consisting of 86 new operators. Rather than using
algebraic identities and integration by parts, we prove the independence of
these interactions in momentum space, including a discussion on evanescent
bosonic operators. Our results pave the way for renormalising the SM effective
field theory (SMEFT), as well as for performing matching of ultraviolet models
onto the SMEFT, to higher order. To demonstrate the potential of our
construction, we have implemented our basis in matchmakereft and used it to
integrate out a heavy singlet scalar and a heavy quadruplet scalar up to one
loop. We provide the corresponding dimension-eight Wilson coefficients.
Likewise, we show how our results can be easily used to simplify cumbersome
redundant Lagrangians arising, for example, from integrating out heavy fields
using the path-integral approach to matching.
| [
{
"created": "Thu, 23 Dec 2021 17:21:45 GMT",
"version": "v1"
}
] | 2022-06-08 | [
[
"Chala",
"Mikael",
""
],
[
"Díaz-Carmona",
"Álvaro",
""
],
[
"Guedes",
"Guilherme",
""
]
] | We present a basis of dimension-eight Green's functions involving Standard Model (SM) bosonic fields, consisting of 86 new operators. Rather than using algebraic identities and integration by parts, we prove the independence of these interactions in momentum space, including a discussion on evanescent bosonic operators. Our results pave the way for renormalising the SM effective field theory (SMEFT), as well as for performing matching of ultraviolet models onto the SMEFT, to higher order. To demonstrate the potential of our construction, we have implemented our basis in matchmakereft and used it to integrate out a heavy singlet scalar and a heavy quadruplet scalar up to one loop. We provide the corresponding dimension-eight Wilson coefficients. Likewise, we show how our results can be easily used to simplify cumbersome redundant Lagrangians arising, for example, from integrating out heavy fields using the path-integral approach to matching. |
1707.05783 | Angelo Monteux | Pouya Asadi, Matthew R. Buckley, Anthony DiFranzo, Angelo Monteux and
David Shih | Digging Deeper for New Physics in the LHC Data | 31 pages + appendices, 14 figures, source code for recasted searches
attached as auxiliary material | null | 10.1007/JHEP11(2017)194 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we describe a novel, model-independent technique of
"rectangular aggregations" for mining the LHC data for hints of new physics. A
typical (CMS) search now has hundreds of signal regions, which can obscure
potentially interesting anomalies. Applying our technique to the two CMS
jets+MET SUSY searches, we identify a set of previously overlooked $\sim
3\sigma$ excesses. Among these, four excesses survive tests of inter- and
intra-search compatibility, and two are especially interesting: they are
largely overlapping between the jets+MET searches and are characterized by low
jet multiplicity, zero $b$-jets, and low MET and $H_T$. We find that resonant
color-triplet production decaying to a quark plus an invisible particle
provides an excellent fit to these two excesses and all other data -- including
the ATLAS jets+MET search, which actually sees a correlated excess. We discuss
the additional constraints coming from dijet resonance searches, monojet
searches and pair production. Based on these results, we believe the
wide-spread view that the LHC data contains no interesting excesses is greatly
exaggerated.
| [
{
"created": "Tue, 18 Jul 2017 18:00:00 GMT",
"version": "v1"
}
] | 2018-01-17 | [
[
"Asadi",
"Pouya",
""
],
[
"Buckley",
"Matthew R.",
""
],
[
"DiFranzo",
"Anthony",
""
],
[
"Monteux",
"Angelo",
""
],
[
"Shih",
"David",
""
]
] | In this paper we describe a novel, model-independent technique of "rectangular aggregations" for mining the LHC data for hints of new physics. A typical (CMS) search now has hundreds of signal regions, which can obscure potentially interesting anomalies. Applying our technique to the two CMS jets+MET SUSY searches, we identify a set of previously overlooked $\sim 3\sigma$ excesses. Among these, four excesses survive tests of inter- and intra-search compatibility, and two are especially interesting: they are largely overlapping between the jets+MET searches and are characterized by low jet multiplicity, zero $b$-jets, and low MET and $H_T$. We find that resonant color-triplet production decaying to a quark plus an invisible particle provides an excellent fit to these two excesses and all other data -- including the ATLAS jets+MET search, which actually sees a correlated excess. We discuss the additional constraints coming from dijet resonance searches, monojet searches and pair production. Based on these results, we believe the wide-spread view that the LHC data contains no interesting excesses is greatly exaggerated. |
1609.09235 | Hiroyuki Umeeda Dr. | Daiji Kimura, Takuya Morozumi, Hiroyuki Umeeda | Analysis of Dalitz decays with intrinsic parity violating interactions
in resonance chiral perturbation theory | 73 pages, 17 figures, 13 tables. Version accepted in PTEP | Prog Theor Exp Phys (2018) | 10.1093/ptep/pty122 | HUPD1608 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Observables of light hadron decays are analyzed in a model of chiral
Lagrangian which includes resonance fields of vector mesons. In particular,
transition form factors are investigated for Dalitz decays of $V\to Pl^+l^-$
and $P\to \gamma l^+l^-$ $(V=1^-, P=0^-)$. Moreover, the differential decay
width of $P\to \pi^+\pi^-\gamma$ and the partial widths of $P\to2\gamma, V\to
P\gamma, \eta^\prime\to V\gamma, \phi(1020)\to\omega(782)\pi^0$ and $V\to 3P$
are also calculated. In this study, we consider a model which contains octet
and singlet fields as representation of $SU(3)$. As an extension of chiral
perturbation theory, we include 1-loop ordered interaction terms. For both
pseudoscalar and vector meson, we evaluate mixing matrices in which
isospin/$SU(3)$ breaking is taken into account. Furthermore, intrinsic parity
violating interactions are considered with singlet fields. For parameter
estimation, we carry out $\chi^2$ fittings in which a spectral function of
$\tau$ decays, vector meson masses, decay widths of $V\to P\gamma$ and
transition form factor of $V\to Pl^+l^-$ are utilized as input data. Using the
estimated parameter region in the model, we give predictions for decay widths
and transition form factors of intrinsic parity violating decays. As further
model predictions, we calculate the transition form factors of $\phi(1020)\to
\pi^0l^+l^-$ and $\eta^\prime\to\gamma l^+l^-$ in the vicinity of resonance
regions, taking account of the contribution for intermediate $\rho(770)$ and
$\omega(782)$.
| [
{
"created": "Thu, 29 Sep 2016 07:36:45 GMT",
"version": "v1"
},
{
"created": "Sat, 18 Nov 2017 05:07:13 GMT",
"version": "v2"
},
{
"created": "Tue, 30 Oct 2018 08:44:18 GMT",
"version": "v3"
}
] | 2019-12-06 | [
[
"Kimura",
"Daiji",
""
],
[
"Morozumi",
"Takuya",
""
],
[
"Umeeda",
"Hiroyuki",
""
]
] | Observables of light hadron decays are analyzed in a model of chiral Lagrangian which includes resonance fields of vector mesons. In particular, transition form factors are investigated for Dalitz decays of $V\to Pl^+l^-$ and $P\to \gamma l^+l^-$ $(V=1^-, P=0^-)$. Moreover, the differential decay width of $P\to \pi^+\pi^-\gamma$ and the partial widths of $P\to2\gamma, V\to P\gamma, \eta^\prime\to V\gamma, \phi(1020)\to\omega(782)\pi^0$ and $V\to 3P$ are also calculated. In this study, we consider a model which contains octet and singlet fields as representation of $SU(3)$. As an extension of chiral perturbation theory, we include 1-loop ordered interaction terms. For both pseudoscalar and vector meson, we evaluate mixing matrices in which isospin/$SU(3)$ breaking is taken into account. Furthermore, intrinsic parity violating interactions are considered with singlet fields. For parameter estimation, we carry out $\chi^2$ fittings in which a spectral function of $\tau$ decays, vector meson masses, decay widths of $V\to P\gamma$ and transition form factor of $V\to Pl^+l^-$ are utilized as input data. Using the estimated parameter region in the model, we give predictions for decay widths and transition form factors of intrinsic parity violating decays. As further model predictions, we calculate the transition form factors of $\phi(1020)\to \pi^0l^+l^-$ and $\eta^\prime\to\gamma l^+l^-$ in the vicinity of resonance regions, taking account of the contribution for intermediate $\rho(770)$ and $\omega(782)$. |
1312.5588 | Bj\"orn Schenke | Bjoern Schenke, Prithwish Tribedy, Raju Venugopalan | Gluon field fluctuations in nuclear collisions: Multiplicity and
eccentricity distributions | 8 pages, 6 figures, submitted to the Special Issue of Nuclear Physics
A: Proceedings of the IS2013 Conference, September 8-14 2013, Illa da Toxa -
Galicia (Spain) | null | 10.1016/j.nuclphysa.2014.03.001 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss different sources of fluctuations in nuclear collisions and their
realization in the IP-Glasma model. We present results for multiplicity
distributions in p+p and p+A collisions and compare eccentricity distributions
in A+A collisions to the flow harmonic distributions in 10 centrality classes
measured by the ATLAS collaboration.
| [
{
"created": "Thu, 19 Dec 2013 15:30:05 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Schenke",
"Bjoern",
""
],
[
"Tribedy",
"Prithwish",
""
],
[
"Venugopalan",
"Raju",
""
]
] | We discuss different sources of fluctuations in nuclear collisions and their realization in the IP-Glasma model. We present results for multiplicity distributions in p+p and p+A collisions and compare eccentricity distributions in A+A collisions to the flow harmonic distributions in 10 centrality classes measured by the ATLAS collaboration. |
hep-ph/0507080 | Hrachia Asatrian M | V. A. Poghosyan | Package for Calculations and Simplifications of Expressions with Dirac
Matrixes (MatrixExp) | null | Comput.Phys.Commun. 170 (2005) 287-295 | 10.1016/j.cpc.2005.06.002 | null | hep-ph | null | This paper describes a package for calculations of expressions with Dirac
matrixes. Advantages to existing similar packages are described. MatrixExp
package is intended for simplification of complex expressions involving
$\gamma$-matrixes, providing such tools as automatic Feynman parameterization,
integration in $d$-dimensional space, sorting and grouping of results in a
given order. Also, in comparison with existing similar package Tracer,
presented package MatrixExp has more enhanced input possibility. User-available
functions of MatrixExp package are described in detail. Also an example of
calculation of Feynman diagram for process $b\to s\gamma g$ with application of
functions of MatrixExp package is presented.
| [
{
"created": "Thu, 7 Jul 2005 14:19:44 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Poghosyan",
"V. A.",
""
]
] | This paper describes a package for calculations of expressions with Dirac matrixes. Advantages to existing similar packages are described. MatrixExp package is intended for simplification of complex expressions involving $\gamma$-matrixes, providing such tools as automatic Feynman parameterization, integration in $d$-dimensional space, sorting and grouping of results in a given order. Also, in comparison with existing similar package Tracer, presented package MatrixExp has more enhanced input possibility. User-available functions of MatrixExp package are described in detail. Also an example of calculation of Feynman diagram for process $b\to s\gamma g$ with application of functions of MatrixExp package is presented. |
1607.05569 | Wolfgang Lucha | Wolfgang Lucha, Dmitri Melikhov, Hagop Sazdjian, Silvano Simula | Charmed Mesons and Charmonia: Three-Meson Strong Couplings | 5 pages, 3 figures, contributed to "QCD@Work 2016 - International
Workshop on Quantum Chromodynamics: Theory and Experiment" (27 - 30 June
2016, Martina Franca, Italy) | EPJ Web of Conferences 129 (2016) 00025 | 10.1051/epjconf/201612900025 | HEPHY-PUB 970/16 (2016) | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Revisiting the strong couplings of three mesons, each of which involves at
least one charm quark, proves clear disaccord between quark-model and QCD
sum-rule results.
| [
{
"created": "Tue, 19 Jul 2016 13:37:14 GMT",
"version": "v1"
}
] | 2016-12-06 | [
[
"Lucha",
"Wolfgang",
""
],
[
"Melikhov",
"Dmitri",
""
],
[
"Sazdjian",
"Hagop",
""
],
[
"Simula",
"Silvano",
""
]
] | Revisiting the strong couplings of three mesons, each of which involves at least one charm quark, proves clear disaccord between quark-model and QCD sum-rule results. |
1606.00840 | Dreyer Fr\'ed\'eric | Fr\'ed\'eric A. Dreyer and Alexander Karlberg | Vector-boson fusion Higgs production at N$^3$LO in QCD | 5 pages, 4 figures | Phys. Rev. Lett. 117, 072001 (2016) | 10.1103/PhysRevLett.117.072001 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the next-to-next-to-next-to-leading-order (N$^3$LO) QCD
corrections to inclusive vector-boson fusion (VBF) Higgs production at proton
colliders, in the limit in which there is no colour exchange between the
hadronic systems associated with the two colliding protons. We also provide
differential cross sections for the Higgs transverse momentum and rapidity
distributions. We find that the corrections are at the 1-2 permille level, well
within the scale-uncertainty of the next-to-next-to-leading-order (NNLO)
calculation. The associated scale-uncertainty of the N$^3$LO calculation is
typically found to be below the 2 permille level. We also consider theoretical
uncertainties due to missing higher order parton distribution functions, and
provide an estimate of their importance.
| [
{
"created": "Thu, 2 Jun 2016 20:00:02 GMT",
"version": "v1"
}
] | 2016-08-17 | [
[
"Dreyer",
"Frédéric A.",
""
],
[
"Karlberg",
"Alexander",
""
]
] | We calculate the next-to-next-to-next-to-leading-order (N$^3$LO) QCD corrections to inclusive vector-boson fusion (VBF) Higgs production at proton colliders, in the limit in which there is no colour exchange between the hadronic systems associated with the two colliding protons. We also provide differential cross sections for the Higgs transverse momentum and rapidity distributions. We find that the corrections are at the 1-2 permille level, well within the scale-uncertainty of the next-to-next-to-leading-order (NNLO) calculation. The associated scale-uncertainty of the N$^3$LO calculation is typically found to be below the 2 permille level. We also consider theoretical uncertainties due to missing higher order parton distribution functions, and provide an estimate of their importance. |
hep-ph/0603144 | Branimir Zauner | S. Ceci, A. Svarc and B. Zauner | The piN --> etaN data demand the existence of N(1710) P11 resonance
reducing the 1700 MeV continuum ambiguity | 4 pages, 3 figures | Phys.Rev.Lett.97:062002,2006 | 10.1103/PhysRevLett.97.062002 | null | hep-ph | null | In spite of prolonged polemics, the agreement on the existence of N(1710) P11
resonance has not until now been reached, and the Particle Data Group declares
it as a 3-star resonance only. We show that the proper inclusion of inelastic
channels in the coupled-channel formalism indisputably demands the existence of
N(1710) P11 state, and that it presumably stays "hidden" within the continuum
ambiguity of any typical single channel partial wave analyses. Consequently,
its Particle Data Group confidence rating should be raised to a 4-star
resonance.
| [
{
"created": "Mon, 20 Mar 2006 10:03:59 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Ceci",
"S.",
""
],
[
"Svarc",
"A.",
""
],
[
"Zauner",
"B.",
""
]
] | In spite of prolonged polemics, the agreement on the existence of N(1710) P11 resonance has not until now been reached, and the Particle Data Group declares it as a 3-star resonance only. We show that the proper inclusion of inelastic channels in the coupled-channel formalism indisputably demands the existence of N(1710) P11 state, and that it presumably stays "hidden" within the continuum ambiguity of any typical single channel partial wave analyses. Consequently, its Particle Data Group confidence rating should be raised to a 4-star resonance. |
hep-ph/0212176 | N. Nikolaev | I.P. Ivanov (Institute of Mathematics, Novosibirsk), N.N. Nikolaev
(IKP, Forshcungszentrum Juelich and L.D.Landau Inst.), W. Sch\"afer (IKP,
Forshcungszentrum Juelich), B.G. Zakharov (L.D.Landau Inst., Chernogolovka),
V.R. Zoller (ITEP, Moscow) | High Density QCD, Saturation and Diffractive DIS | 13 pages, 4 figures, Invited talk at NATO Advanced Research Workshop
On Diffraction 2002, 31 Aug - 6 Sep 2002, Alushta, Ukraine | null | 10.1142/9789812704962_0034 | null | hep-ph | null | We review a consistent description of the fusion and saturation of partons in
the Lorentz-contracted ultrarelativistic nuclei in terms of a nuclear
attenuation of color dipole states of the photon and collective
Weizs\"acker-Williams (WW) gluon structure function of a nucleus. Diffractive
DIS provides a basis for the definition of the WW nuclear glue. The point that
all observables for DIS off nuclei are uniquely calculable in terms of the
nuclear WW glue amounts to a new form of factorization in the saturation
regime.
| [
{
"created": "Thu, 12 Dec 2002 16:59:45 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Ivanov",
"I. P.",
"",
"Institute of Mathematics, Novosibirsk"
],
[
"Nikolaev",
"N. N.",
"",
"IKP, Forshcungszentrum Juelich and L.D.Landau Inst."
],
[
"Schäfer",
"W.",
"",
"IKP,\n Forshcungszentrum Juelich"
],
[
"Zakharov",
"B. G.",
"",
... | We review a consistent description of the fusion and saturation of partons in the Lorentz-contracted ultrarelativistic nuclei in terms of a nuclear attenuation of color dipole states of the photon and collective Weizs\"acker-Williams (WW) gluon structure function of a nucleus. Diffractive DIS provides a basis for the definition of the WW nuclear glue. The point that all observables for DIS off nuclei are uniquely calculable in terms of the nuclear WW glue amounts to a new form of factorization in the saturation regime. |
2203.07048 | Mike Williams | Daniel Craik, Phil Ilten, Daniel Johnson, Mike Williams | LHCb future dark-sector sensitivity projections for Snowmass 2021 | contribution to Snowmass 2021 | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We provide future LHCb dark-sector sensitivity projections for use in the
Snowmass reports. These include updated projections for dark photons and the
Higgs portal, along with new projections for axion-like particles that couple
predominantly to gluons.
| [
{
"created": "Mon, 14 Mar 2022 12:36:58 GMT",
"version": "v1"
}
] | 2022-03-15 | [
[
"Craik",
"Daniel",
""
],
[
"Ilten",
"Phil",
""
],
[
"Johnson",
"Daniel",
""
],
[
"Williams",
"Mike",
""
]
] | We provide future LHCb dark-sector sensitivity projections for use in the Snowmass reports. These include updated projections for dark photons and the Higgs portal, along with new projections for axion-like particles that couple predominantly to gluons. |
0804.4337 | Aurore Courtoy | A. Courtoy, S. Noguera | Pion-Photon Transition Distribution Amplitudes | To appear in the proceedings of the Joint Meeting
Heidelberg-Liege-Paris-Wroclaw (HLPW08), Spa, Belgium, 6-8 March 2008; uses
aip-6s.clo, aipproc.cls and aipxfm.sty (included) | AIPConf.Proc.1038:249-258,2008 | 10.1063/1.2987178 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The newly introduced Transition Distribution Amplitudes (TDAs) are discussed
for the $\pi$-$\gamma$ transitions. Relations between $\pi$-$\gamma$ and
$\gamma$-$\pi$ TDAs for different cases are given. Numerical values for the
$\pi$-$\gamma$ TDAs in different models are compared. GPD's features are
extended to TDAs and the role of PCAC highlighted. We give hints for the
evaluation of cross sections for meson pair production in our approach.
| [
{
"created": "Mon, 28 Apr 2008 14:31:49 GMT",
"version": "v1"
},
{
"created": "Wed, 7 May 2008 16:57:41 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Courtoy",
"A.",
""
],
[
"Noguera",
"S.",
""
]
] | The newly introduced Transition Distribution Amplitudes (TDAs) are discussed for the $\pi$-$\gamma$ transitions. Relations between $\pi$-$\gamma$ and $\gamma$-$\pi$ TDAs for different cases are given. Numerical values for the $\pi$-$\gamma$ TDAs in different models are compared. GPD's features are extended to TDAs and the role of PCAC highlighted. We give hints for the evaluation of cross sections for meson pair production in our approach. |
0906.2728 | Orhan Cakir | O. Cakir (Ankara U.) and K.O. Ozansoy (Ankara U.) | Searching Unparticle Signatures Through Tau Pair Production | 8 pages, 10 figures, 2 tables | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we study the possible unparticle signatures through tau pair
production e+e- -> tau+tau- process at the low energy particle factories. We
take into account lepton flavor conserving (s-channel) and violating
(t-channel) couplings for the unparticle leptonic interactions. For different
values of the scaling parameter d we extract upper limits on the scalar
unparticle couplings at the integrated luminosities of 100/fb.yr and 1
ab/fb.yr.
| [
{
"created": "Mon, 15 Jun 2009 15:47:28 GMT",
"version": "v1"
}
] | 2009-06-16 | [
[
"Cakir",
"O.",
"",
"Ankara U."
],
[
"Ozansoy",
"K. O.",
"",
"Ankara U."
]
] | In this work, we study the possible unparticle signatures through tau pair production e+e- -> tau+tau- process at the low energy particle factories. We take into account lepton flavor conserving (s-channel) and violating (t-channel) couplings for the unparticle leptonic interactions. For different values of the scaling parameter d we extract upper limits on the scalar unparticle couplings at the integrated luminosities of 100/fb.yr and 1 ab/fb.yr. |
1908.03102 | Andrzej Kup\'s\'c Dr | Patrik Adlarson and Andrzej Kupsc | CP symmetry tests in the cascade-anticascade decay of charmonium | 5 pages, 1 figure | Phys. Rev. D 100, 114005 (2019) | 10.1103/PhysRevD.100.114005 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze joint angular distributions of a charmonium decay to the
$\Xi\bar\Xi$ pair using the $\Xi\to\Lambda\pi\to p\pi^-\pi$ weak decay chain
for the cascade and the charge conjugated mode for the anticascade. The decays
allow a direct comparison of the baryon and antibaryon decay properties and a
sensitive test of CP symmetry in the strange baryon sector. We show that all
involved decay parameters can be determined separately in vector and
(pseudo)scalar charmonia decays into $\Xi\bar\Xi$ due to the spin correlations
between the weak decay chains. Contrary to the recently measured $e^+e^-\to
J/\psi\to \Lambda\bar\Lambda$ process, the transverse polarization of the
cascade is not needed and has almost no impact on the uncertainties of the
decay parameters.
| [
{
"created": "Thu, 8 Aug 2019 14:48:07 GMT",
"version": "v1"
}
] | 2019-12-11 | [
[
"Adlarson",
"Patrik",
""
],
[
"Kupsc",
"Andrzej",
""
]
] | We analyze joint angular distributions of a charmonium decay to the $\Xi\bar\Xi$ pair using the $\Xi\to\Lambda\pi\to p\pi^-\pi$ weak decay chain for the cascade and the charge conjugated mode for the anticascade. The decays allow a direct comparison of the baryon and antibaryon decay properties and a sensitive test of CP symmetry in the strange baryon sector. We show that all involved decay parameters can be determined separately in vector and (pseudo)scalar charmonia decays into $\Xi\bar\Xi$ due to the spin correlations between the weak decay chains. Contrary to the recently measured $e^+e^-\to J/\psi\to \Lambda\bar\Lambda$ process, the transverse polarization of the cascade is not needed and has almost no impact on the uncertainties of the decay parameters. |
2002.04213 | Fei Huang | Ai-Chao Wang, Wen-Ling Wang, Fei Huang | Nucleon and $\Delta$ resonances in $\gamma p \to K^+ \Sigma^0(1385)$
photoproduction | 11 pages, 9 figures. Version published in PRD. arXiv admin note: text
overlap with arXiv:1704.04562, arXiv:1810.07012 | Phys. Rev. D 101, 074025 (2020) | 10.1103/PhysRevD.101.074025 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The photoproduction of $\gamma p \to K^+ \Sigma^0(1385)$ is investigated
based on an effective Lagrangian approach using the tree-level Born
approximation, with the purpose of understanding the reaction mechanisms and
resonance contents and their associated parameters in this reaction. In
addition to the $t$-channel $K$ and $K^\ast(892)$ exchanges, $s$-channel
nucleon ($N$) exchange, $u$-channel $\Lambda$ exchange, and generalized contact
term, the exchanges of a minimum number of $N$ and $\Delta$ resonances in the
$s$ channel are taken into account in constructing the reaction amplitudes to
describe the experimental data. It is found that the most recent differential
cross-section data from the CLAS Collaboration can be well reproduced by
including one of the $N(1895){1/2}^-$, $\Delta(1900){1/2}^-$, and
$\Delta(1930){5/2}^-$ resonances. The reaction mechanisms of $\gamma p \to K^+
\Sigma^0(1385)$ are discussed in detail, and the predictions of the beam and
target asymmetries for this reaction are given. The cross sections of $\gamma p
\to K^0 \Sigma^+(1385)$ are shown to be able to further constrain the
theoretical models and pin down the resonance contents for $\gamma p \to K^+
\Sigma^0(1385)$.
| [
{
"created": "Tue, 11 Feb 2020 05:47:45 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Apr 2020 16:15:02 GMT",
"version": "v2"
}
] | 2020-04-22 | [
[
"Wang",
"Ai-Chao",
""
],
[
"Wang",
"Wen-Ling",
""
],
[
"Huang",
"Fei",
""
]
] | The photoproduction of $\gamma p \to K^+ \Sigma^0(1385)$ is investigated based on an effective Lagrangian approach using the tree-level Born approximation, with the purpose of understanding the reaction mechanisms and resonance contents and their associated parameters in this reaction. In addition to the $t$-channel $K$ and $K^\ast(892)$ exchanges, $s$-channel nucleon ($N$) exchange, $u$-channel $\Lambda$ exchange, and generalized contact term, the exchanges of a minimum number of $N$ and $\Delta$ resonances in the $s$ channel are taken into account in constructing the reaction amplitudes to describe the experimental data. It is found that the most recent differential cross-section data from the CLAS Collaboration can be well reproduced by including one of the $N(1895){1/2}^-$, $\Delta(1900){1/2}^-$, and $\Delta(1930){5/2}^-$ resonances. The reaction mechanisms of $\gamma p \to K^+ \Sigma^0(1385)$ are discussed in detail, and the predictions of the beam and target asymmetries for this reaction are given. The cross sections of $\gamma p \to K^0 \Sigma^+(1385)$ are shown to be able to further constrain the theoretical models and pin down the resonance contents for $\gamma p \to K^+ \Sigma^0(1385)$. |
2102.01795 | Jihn E. Kim | Jihn E. Kim | Anomalies and parities for quintessential and ultra-light axions | null | Phys. Lett. B 817 (2021) 136248 | 10.1016/j.physletb.2021.136248 | null | hep-ph astro-ph.CO hep-th | http://creativecommons.org/publicdomain/zero/1.0/ | We discuss the energy scales of the explicit breaking terms of the global
symmetries \USW~ needed for the quinessential axion (QA) and the ultra-light
axion (ULA). The appropriate scale of QA is about $10^{8}$ GeV.
| [
{
"created": "Tue, 2 Feb 2021 23:16:53 GMT",
"version": "v1"
}
] | 2021-04-23 | [
[
"Kim",
"Jihn E.",
""
]
] | We discuss the energy scales of the explicit breaking terms of the global symmetries \USW~ needed for the quinessential axion (QA) and the ultra-light axion (ULA). The appropriate scale of QA is about $10^{8}$ GeV. |
hep-ph/0503200 | Zhi-Zhong Xing | Zhi-zhong Xing | Nontrivial Correlation between the CKM and MNS Matrices | RevTex 12 pages (1 PS figure) | Phys.Lett. B618 (2005) 141-149 | 10.1016/j.physletb.2005.05.040 | null | hep-ph | null | We point out that the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix
$V_{\rm CKM}$ and the Maki-Nakagawa-Sakata (MNS) lepton mixing matrix $V_{\rm
MNS}$ can naturally be correlated in a class of seesaw models with grand
unification, but the texture of their correlation matrix ${\cal F}_\nu$ is
rather nontrivial. The bimaximal mixing pattern of ${\cal F}_\nu$ is disfavored
by current data, and other special forms of ${\cal F}_\nu$ may suffer from
fine-tuning of the free phase parameters in fitting the so-called quark-lepton
complementarity relation. A straightforward calculation of ${\cal F}_\nu$ in
terms of $V_{\rm CKM}$ and $V_{\rm MNS}$ reveals a striking feature of ${\cal
F}_\nu$: its (1,3) element cannot be zero or too small, no matter whether the
(1,3) elements of $V_{\rm CKM}$ and $V_{\rm MNS}$ are vanishing or not. We also
add some brief comments on possible radiative corrections to $V_{\rm CKM}$ and
$V_{\rm MNS}$.
| [
{
"created": "Mon, 21 Mar 2005 12:20:15 GMT",
"version": "v1"
},
{
"created": "Wed, 18 May 2005 09:00:16 GMT",
"version": "v2"
},
{
"created": "Wed, 25 May 2005 07:38:32 GMT",
"version": "v3"
}
] | 2009-11-11 | [
[
"Xing",
"Zhi-zhong",
""
]
] | We point out that the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix $V_{\rm CKM}$ and the Maki-Nakagawa-Sakata (MNS) lepton mixing matrix $V_{\rm MNS}$ can naturally be correlated in a class of seesaw models with grand unification, but the texture of their correlation matrix ${\cal F}_\nu$ is rather nontrivial. The bimaximal mixing pattern of ${\cal F}_\nu$ is disfavored by current data, and other special forms of ${\cal F}_\nu$ may suffer from fine-tuning of the free phase parameters in fitting the so-called quark-lepton complementarity relation. A straightforward calculation of ${\cal F}_\nu$ in terms of $V_{\rm CKM}$ and $V_{\rm MNS}$ reveals a striking feature of ${\cal F}_\nu$: its (1,3) element cannot be zero or too small, no matter whether the (1,3) elements of $V_{\rm CKM}$ and $V_{\rm MNS}$ are vanishing or not. We also add some brief comments on possible radiative corrections to $V_{\rm CKM}$ and $V_{\rm MNS}$. |
hep-ph/0412384 | Mustafa Savci | T. M. Aliev, V. Bashiry, M. Savci | Polarized forward-backward asymmetries of leptons in (B_s -> l^+ l^-
gamma) decay | 26 pages, 22 figures, LaTeX formatted | Eur.Phys.J.C40:505-514,2005 | 10.1140/epjc/s2005-02150-0 | metu-phys-hep-0412021 | hep-ph | null | Polarized forward-backward asymmetries in the (B_s -> l^+ l^- gamma) decay
are calculated using the most general, model independent form of the effective
Hamiltonian, including all possible forms of interactions. The dependencies of
the asymmetries on new Wilson coefficients are investigated. The detectability
of the asymmetries at LHC is discussed.
| [
{
"created": "Sun, 26 Dec 2004 17:03:44 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Aliev",
"T. M.",
""
],
[
"Bashiry",
"V.",
""
],
[
"Savci",
"M.",
""
]
] | Polarized forward-backward asymmetries in the (B_s -> l^+ l^- gamma) decay are calculated using the most general, model independent form of the effective Hamiltonian, including all possible forms of interactions. The dependencies of the asymmetries on new Wilson coefficients are investigated. The detectability of the asymmetries at LHC is discussed. |
0705.2241 | D. J. Miller | Peter Athron and D. J. Miller | A New Measure of Fine Tuning | 25 pages, some colour figures; version accepted for publication | Phys.Rev.D76:075010,2007 | 10.1103/PhysRevD.76.075010 | null | hep-ph | null | The solution to fine tuning is one of the principal motivations for Beyond
the Standard Model (BSM) Studies. However constraints on new physics indicate
that many of these BSM models are also fine tuned (although to a much lesser
extent). To compare these BSM models it is essential that we have a reliable,
quantitative measure of tuning. We review the measures of tuning used in the
literature and propose an alternative measure. We apply this measure to several
toy models and the Minimal Supersymmetric Standard Model.
| [
{
"created": "Tue, 15 May 2007 20:47:03 GMT",
"version": "v1"
},
{
"created": "Mon, 21 May 2007 16:34:51 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Nov 2007 17:33:50 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Athron",
"Peter",
""
],
[
"Miller",
"D. J.",
""
]
] | The solution to fine tuning is one of the principal motivations for Beyond the Standard Model (BSM) Studies. However constraints on new physics indicate that many of these BSM models are also fine tuned (although to a much lesser extent). To compare these BSM models it is essential that we have a reliable, quantitative measure of tuning. We review the measures of tuning used in the literature and propose an alternative measure. We apply this measure to several toy models and the Minimal Supersymmetric Standard Model. |
hep-ph/0501146 | Mihai L. Ion | D. B. Ion (1 and 2) and M. L. D. Ion (3) ((1) TH Division, CERN, (2)
NIPNE-HH, Bucharest, Romania, (3) University of Bucharest, Department of
Atomic and Nuclear Physics, Romania) | A New Optimal Bound on Logarithmic Slope of Elastic Hadron-Hadron
Scattering | format revtex4, 4 pages, 1 figure | Rom.J.Phys.52:741-750,2007 | null | null | hep-ph | null | In this paper we prove a new optimal bound on the logarithmic slope of the
elastic slope when: elastic cross section and differential cross sections in
forward and backward directions are known from experimental data. The results
on the experimental tests of this new optimal bound are presented in Sect. 3
for the principal meson-nucleon elastic scatterings: pion-nucleon, kaon-nucleon
at all available energies. Then we have shown that the saturation of this
optimal bound is observed with high accuracy practically at all available
energies in meson-nucleon scattering.
| [
{
"created": "Sun, 16 Jan 2005 13:49:12 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Ion",
"D. B.",
"",
"1 and 2"
],
[
"Ion",
"M. L. D.",
""
]
] | In this paper we prove a new optimal bound on the logarithmic slope of the elastic slope when: elastic cross section and differential cross sections in forward and backward directions are known from experimental data. The results on the experimental tests of this new optimal bound are presented in Sect. 3 for the principal meson-nucleon elastic scatterings: pion-nucleon, kaon-nucleon at all available energies. Then we have shown that the saturation of this optimal bound is observed with high accuracy practically at all available energies in meson-nucleon scattering. |
1607.04020 | Wei Wang | Feng-Kun Guo, Ulf-G. Mei{\ss}ner, Wei Wang | On the constituent counting rules for hard exclusive processes involving
multiquark states | 10 pages, 3 figures | Chinese Physics C, 41 (2017) 053108 | 10.1088/1674-1137/41/5/053108 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | At high energies, the cross section of a hard exclusive process at finite
scattering angle falls off as a negative power of the center-of-mass energy
$\sqrt{s}$. If all involved quark-gluon compositions undergo hard momentum
transfers, the scaling of the fall-off is determined by the underlying valence
structures of the initial and final states, known as the constituent counting
rules. It was argued in the literature that the counting rules are a powerful
tool to determine the valence degrees of freedom inside multiquark states when
applied to exclusive production processes. However, we demonstrate that for
hadrons with hidden flavors the naive application of the constituent counting
rules is problematic, since it is not mandatory for all components to
participate the hard scattering at the scale $\sqrt{s}$. The correct scaling
rules can be obtained easily by using effective field theory. A few examples
involving the $Z_c(3900)^\pm$ and $X(3872)$ are discussed.
| [
{
"created": "Thu, 14 Jul 2016 07:55:09 GMT",
"version": "v1"
}
] | 2017-02-20 | [
[
"Guo",
"Feng-Kun",
""
],
[
"Meißner",
"Ulf-G.",
""
],
[
"Wang",
"Wei",
""
]
] | At high energies, the cross section of a hard exclusive process at finite scattering angle falls off as a negative power of the center-of-mass energy $\sqrt{s}$. If all involved quark-gluon compositions undergo hard momentum transfers, the scaling of the fall-off is determined by the underlying valence structures of the initial and final states, known as the constituent counting rules. It was argued in the literature that the counting rules are a powerful tool to determine the valence degrees of freedom inside multiquark states when applied to exclusive production processes. However, we demonstrate that for hadrons with hidden flavors the naive application of the constituent counting rules is problematic, since it is not mandatory for all components to participate the hard scattering at the scale $\sqrt{s}$. The correct scaling rules can be obtained easily by using effective field theory. A few examples involving the $Z_c(3900)^\pm$ and $X(3872)$ are discussed. |
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