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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
hep-ph/9808479 | Thierry Gousset | Markus Diehl, Thierry Gousset and Bernard Pire | Exclusive electroproduction of vector mesons and transversity
distributions | 8 pages, 2 figures | Phys.Rev. D59 (1999) 034023 | 10.1103/PhysRevD.59.034023 | null | hep-ph | null | We show that the leading twist contribution to exclusive electroproduction of
transversely polarized vector mesons vanishes at all orders in perturbation
theory. Therefore one cannot extract information on the quark transversity
distribution of the nucleon from this reaction. In turn one has that the
produced vector meson is purely longitudinal in the large-Q^2 limit, which
provides a new test of the dominance of leading twist at finite Q^2.
| [
{
"created": "Mon, 31 Aug 1998 07:50:32 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Diehl",
"Markus",
""
],
[
"Gousset",
"Thierry",
""
],
[
"Pire",
"Bernard",
""
]
] | We show that the leading twist contribution to exclusive electroproduction of transversely polarized vector mesons vanishes at all orders in perturbation theory. Therefore one cannot extract information on the quark transversity distribution of the nucleon from this reaction. In turn one has that the produced vector meson is purely longitudinal in the large-Q^2 limit, which provides a new test of the dominance of leading twist at finite Q^2. |
1002.2857 | Alan D. Martin | V.A. Khoze, A.D. Martin, M.G. Ryskin and A.G. Shuvaev | A new window at the LHC: BSM signals using tagged protons | 15 pages, 3 figures | Eur.Phys.J.C68:125-132,2010 | 10.1140/epjc/s10052-010-1308-4 | IPPP/10/14, DCPT/10/28 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The signature at the LHC of many Beyond the Standard Model (BSM) scenarios is
events with large missing energy. If the forward outgoing protons are measured,
we show that the production and decay of BSM particles in the central rapidity
interval, with gaps in rapidity either side, offers certain advantages over
inclusive production, to search for signals (a) with missing longitudinal
4-momentum (typical of invisible Higgs production), and (b) for new light
pseudoscalar bosons.
| [
{
"created": "Mon, 15 Feb 2010 11:33:26 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Khoze",
"V. A.",
""
],
[
"Martin",
"A. D.",
""
],
[
"Ryskin",
"M. G.",
""
],
[
"Shuvaev",
"A. G.",
""
]
] | The signature at the LHC of many Beyond the Standard Model (BSM) scenarios is events with large missing energy. If the forward outgoing protons are measured, we show that the production and decay of BSM particles in the central rapidity interval, with gaps in rapidity either side, offers certain advantages over inclusive production, to search for signals (a) with missing longitudinal 4-momentum (typical of invisible Higgs production), and (b) for new light pseudoscalar bosons. |
hep-ph/9908316 | John McDonald | Kari Enqvist (Helsinki) and John McDonald (Glasgow) | The Dynamics of Affleck-Dine Condensate Collapse | 21 pages LaTeX, 11 figures | Nucl.Phys. B570 (2000) 407-422 | 10.1016/S0550-3213(99)00776-2 | null | hep-ph | null | In the MSSM, cosmological scalar field condensates formed along flat
directions of the scalar potential (Affleck-Dine condensates) are typically
unstable with respect to formation of Q-balls, a type of non-topological
soliton. We consider the dynamical evolution of the Affleck-Dine condensate in
the MSSM. We discuss the creation and linear growth, in F- and D-term inflation
models, of the quantum seed perturbations which in the non-linear regime
catalyse the collapse of the condensate to non-topological soliton lumps. We
study numerically the evolution of the collapsing condensate lumps and show
that the solitons initially formed are not in general Q-balls, but Q-axitons, a
pseudo-breather which can have very different properties from Q-balls of the
same charge. We calculate the energy and charge radiated from a spherically
symmetric condensate lump as it evolves into a Q-axiton. We also discuss the
implications for baryogenesis and dark matter.
| [
{
"created": "Tue, 10 Aug 1999 10:51:31 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Enqvist",
"Kari",
"",
"Helsinki"
],
[
"McDonald",
"John",
"",
"Glasgow"
]
] | In the MSSM, cosmological scalar field condensates formed along flat directions of the scalar potential (Affleck-Dine condensates) are typically unstable with respect to formation of Q-balls, a type of non-topological soliton. We consider the dynamical evolution of the Affleck-Dine condensate in the MSSM. We discuss the creation and linear growth, in F- and D-term inflation models, of the quantum seed perturbations which in the non-linear regime catalyse the collapse of the condensate to non-topological soliton lumps. We study numerically the evolution of the collapsing condensate lumps and show that the solitons initially formed are not in general Q-balls, but Q-axitons, a pseudo-breather which can have very different properties from Q-balls of the same charge. We calculate the energy and charge radiated from a spherically symmetric condensate lump as it evolves into a Q-axiton. We also discuss the implications for baryogenesis and dark matter. |
2305.08662 | Anupam Ghosh | Anupam Ghosh, Partha Konar | Precision prediction at the LHC of a democratic up-family philic KSVZ
axion model | 25 pages, 10 figures, 6 tables | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this work, we study the $SU(2)_L$ singlet complex scalar extended KSVZ
model that, in addition to providing a natural solution to the strong-CP
problem by including a global Peccei-Quinn symmetry, also furnishes two
components of dark matter that satisfy observer relic density without
fine-tuning of model parameters. Furthermore, this model provides a rich
phenomenology by introducing a vector-like quark whose presence can be sensed
in collider experiments and dark matter production mechanisms. We explore the
possibility of democratic Yukawa interaction of the vector-like quark with all
up-type quarks and scalar dark matter candidate. We also employ next-to-leading
order NLO-QCD correction for VLQ pair production to study a unique search at
the LHC, generating a pair of boosted tops with sizeable missing transverse
momentum. Multivariate analysis with jet substructure variables has a strong
ability to explore a significant parameter space of this model at the 14 TeV
LHC.
| [
{
"created": "Mon, 15 May 2023 14:11:57 GMT",
"version": "v1"
}
] | 2023-05-16 | [
[
"Ghosh",
"Anupam",
""
],
[
"Konar",
"Partha",
""
]
] | In this work, we study the $SU(2)_L$ singlet complex scalar extended KSVZ model that, in addition to providing a natural solution to the strong-CP problem by including a global Peccei-Quinn symmetry, also furnishes two components of dark matter that satisfy observer relic density without fine-tuning of model parameters. Furthermore, this model provides a rich phenomenology by introducing a vector-like quark whose presence can be sensed in collider experiments and dark matter production mechanisms. We explore the possibility of democratic Yukawa interaction of the vector-like quark with all up-type quarks and scalar dark matter candidate. We also employ next-to-leading order NLO-QCD correction for VLQ pair production to study a unique search at the LHC, generating a pair of boosted tops with sizeable missing transverse momentum. Multivariate analysis with jet substructure variables has a strong ability to explore a significant parameter space of this model at the 14 TeV LHC. |
1504.07532 | Sho Ozaki | Sho Ozaki, Takashi Arai, Koichi Hattori and Kazunori Itakura | Euler-Heisenberg-Weiss action for QCD+QED | 36 pages, 10 figures, version published in PRD | Phys. Rev. D 92, 016002 (2015) | 10.1103/PhysRevD.92.016002 | KEK-TH-1815, RIKEN-QHP-189, RBRC-1134 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive an analytic expression for one-loop effective action of QCD+QED at
zero and finite temperatures by using the Schwinger's proper time method. The
result is a nonlinear effective action not only for electromagnetic and
chromo-electromagnetic fields but also the Polyakov loop, and thus reproduces
the Euler-Heisenberg action in QED, QCD, and QED+QCD, and also the Weiss
potential for the Polyakov loop at finite temperature. As applications of this
"Euler-Heisenberg-Weiss" action in QCD+QED, we investigate quark pair
productions induced by QCD+QED fields at zero temperature and the Polyakov loop
in the presence of strong electromagnetic fields. Quark one-loop contribution
to the effective potential of the Polyakov loop explicitly breaks the center
symmetry, and is found to be enhanced by the magnetic field, which is
consistent with the inverse magnetic catalysis observed in lattice QCD
simulation.
| [
{
"created": "Tue, 28 Apr 2015 15:43:07 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Jul 2015 08:11:56 GMT",
"version": "v2"
}
] | 2015-07-22 | [
[
"Ozaki",
"Sho",
""
],
[
"Arai",
"Takashi",
""
],
[
"Hattori",
"Koichi",
""
],
[
"Itakura",
"Kazunori",
""
]
] | We derive an analytic expression for one-loop effective action of QCD+QED at zero and finite temperatures by using the Schwinger's proper time method. The result is a nonlinear effective action not only for electromagnetic and chromo-electromagnetic fields but also the Polyakov loop, and thus reproduces the Euler-Heisenberg action in QED, QCD, and QED+QCD, and also the Weiss potential for the Polyakov loop at finite temperature. As applications of this "Euler-Heisenberg-Weiss" action in QCD+QED, we investigate quark pair productions induced by QCD+QED fields at zero temperature and the Polyakov loop in the presence of strong electromagnetic fields. Quark one-loop contribution to the effective potential of the Polyakov loop explicitly breaks the center symmetry, and is found to be enhanced by the magnetic field, which is consistent with the inverse magnetic catalysis observed in lattice QCD simulation. |
hep-ph/0305127 | Pietro Slavich | Athanasios Dedes, Giuseppe Degrassi and Pietro Slavich | On the two-loop Yukawa corrections to the MSSM Higgs boson masses at
large tan(beta) | 19 pages, 4 eps figures. Some formulae corrected in the Appendix | Nucl.Phys.B672:144-162,2003 | 10.1016/j.nuclphysb.2003.08.033 | MPI-Pht/2003-21, TUM-HEP-507/03, RM3-TH/03-05 | hep-ph | null | We complete the effective potential calculation of the two-loop, top/bottom
Yukawa corrections to the Higgs boson masses in the Minimal Supersymmetric
Standard Model, by computing the O(at^2 + at*ab + ab^2) contributions for
arbitrary values of the bottom Yukawa coupling. We also compute the corrections
to the minimization conditions of the effective potential at the same
perturbative order. Our results extend the existing O(at^2) calculation, and
are relevant in regions of the parameter space corresponding to tan(beta) >> 1.
We extend to the Yukawa corrections a convenient renormalization scheme,
previously proposed for the O(ab*as) corrections, that avoids unphysically
large threshold effects associated with the bottom mass and absorbs the bulk of
the corrections into the one-loop expression. For large values of tan(beta),
the new contributions can account for a variation of several GeV in the
lightest Higgs boson mass.
| [
{
"created": "Mon, 12 May 2003 18:00:23 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Sep 2003 17:13:14 GMT",
"version": "v2"
},
{
"created": "Fri, 3 Oct 2003 14:10:34 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Dedes",
"Athanasios",
""
],
[
"Degrassi",
"Giuseppe",
""
],
[
"Slavich",
"Pietro",
""
]
] | We complete the effective potential calculation of the two-loop, top/bottom Yukawa corrections to the Higgs boson masses in the Minimal Supersymmetric Standard Model, by computing the O(at^2 + at*ab + ab^2) contributions for arbitrary values of the bottom Yukawa coupling. We also compute the corrections to the minimization conditions of the effective potential at the same perturbative order. Our results extend the existing O(at^2) calculation, and are relevant in regions of the parameter space corresponding to tan(beta) >> 1. We extend to the Yukawa corrections a convenient renormalization scheme, previously proposed for the O(ab*as) corrections, that avoids unphysically large threshold effects associated with the bottom mass and absorbs the bulk of the corrections into the one-loop expression. For large values of tan(beta), the new contributions can account for a variation of several GeV in the lightest Higgs boson mass. |
hep-ph/9703460 | Boris Arbuzov | B.A.Arbuzov | HERA high $Q^2$ events as indications of excited leptons with weak
isotopic spin 3/2 | 8 pages, latex, no figures | null | 10.1063/1.54500 | null | hep-ph | null | The H1 and ZEUS anomalous events are interpreted as being due to the
production and the decay of excited leptons $E$, which correspond to spin 1/2
resonances of the first generation lepton doublet ($\nu_e, e$) with W triplet.
This assumption is supported by considering of Bethe-Salpeter equation in the
ladder approximation with anomalous triple gauge boson vertex. The solution
with weak isospin $I = 3/2$ is shown to exist for zero mass state, that means
M_E$ is small in comparison with TeV mass scale. The coupling of $E$ with
leptons and $W$ is defined by the normalization condition. Calculation of the
$E$ width and the production cross-sections agrees with HERA data for value of
the triple $W$ coupling constant $\lambda \simeq 0.5$. Isotopic relations for
different channels are presented as a tool for checking the interpretation.
| [
{
"created": "Mon, 31 Mar 1997 16:35:51 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Arbuzov",
"B. A.",
""
]
] | The H1 and ZEUS anomalous events are interpreted as being due to the production and the decay of excited leptons $E$, which correspond to spin 1/2 resonances of the first generation lepton doublet ($\nu_e, e$) with W triplet. This assumption is supported by considering of Bethe-Salpeter equation in the ladder approximation with anomalous triple gauge boson vertex. The solution with weak isospin $I = 3/2$ is shown to exist for zero mass state, that means M_E$ is small in comparison with TeV mass scale. The coupling of $E$ with leptons and $W$ is defined by the normalization condition. Calculation of the $E$ width and the production cross-sections agrees with HERA data for value of the triple $W$ coupling constant $\lambda \simeq 0.5$. Isotopic relations for different channels are presented as a tool for checking the interpretation. |
1302.3542 | Joachim Brod | Joachim Brod | Direct CP violation in singly Cabibbo-suppressed D-meson decays | 5 pages, 1 figure; Proceedings of CKM 2012, the 7th International
Workshop on the CKM Unitarity Triangle, University of Cincinnati, USA, 28
September - 2 October 2012 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The LHCb and CDF collaborations reported a surprisingly large difference
between the direct CP asymmetries, Delta A_CP, in the D0 -> K+ K- and D0 -> pi+
pi- decay modes. We show that this measurement can be plausibly explained
within the standard model under the assumption of large penguin contractions
matrix elements and nominal U-spin breaking. A consistent picture arises,
accommodating the large difference between the decay rates, and the measured
decay rates of the D -> K pi modes.
| [
{
"created": "Thu, 14 Feb 2013 20:36:25 GMT",
"version": "v1"
}
] | 2013-02-15 | [
[
"Brod",
"Joachim",
""
]
] | The LHCb and CDF collaborations reported a surprisingly large difference between the direct CP asymmetries, Delta A_CP, in the D0 -> K+ K- and D0 -> pi+ pi- decay modes. We show that this measurement can be plausibly explained within the standard model under the assumption of large penguin contractions matrix elements and nominal U-spin breaking. A consistent picture arises, accommodating the large difference between the decay rates, and the measured decay rates of the D -> K pi modes. |
0803.0001 | Jose Kenichi Mizukoshi | R.H.K. Kadala, P.G. Mercadante, J.K. Mizukoshi, Xerxes Tata | Heavy-flavour tagging and the supersymmetry reach of the CERN Large
Hadron Collider | Minor changes in the text, with addition and update of the
references. To be published in the European Physical Journal C | Eur.Phys.J.C56:511-528,2008 | 10.1140/epjc/s10052-008-0672-9 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The branching fraction for the decays of gluinos to third generation quarks
is expected to be enhanced in classes of supersymmetric models where either
third generation squarks are lighter than other squarks, or in mixed-higgsino
dark matter models constructed to be in concordance with the measured density
of cold dark matter. In such scenarios, gluino production events at the CERN
Large Hadron Collider should be rich in top and bottom quark jets. Requiring
b-jets in addition to missing transverse energy should, therefore, enhance the
supersymmetry signal relative to Standard Model backgrounds from V + jet, VV
and QCD backgrounds (V=W, Z). We quantify the increase in the supersymmetry
reach of the LHC from b-tagging in a variety of well-motivated models of
supersymmetry. We also explore ``top-tagging'' at the LHC. We find that while
the efficiency for this turns out to be too low to give an increase in reach
beyond that obtained via b-tagging, top-tagging can indeed provide a
confirmatory signal if gluinos are not too heavy. Finally, we explore the
prospects for detecting the direct production of third generation squarks in
models with an inverted squark mass hierarchy. This is signalled by b-jets +
missing transverse energy events harder than in the Standard Model, but softer
than those from the production of gluinos and heavier squarks. We find that
while these events can be readily separated from SM background (for third
generation squark masses ~300-500 GeV), the contamination from the much heavier
gluinos and squarks remains formidable if these are also accessible.
| [
{
"created": "Fri, 29 Feb 2008 21:00:21 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Aug 2008 21:25:11 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Kadala",
"R. H. K.",
""
],
[
"Mercadante",
"P. G.",
""
],
[
"Mizukoshi",
"J. K.",
""
],
[
"Tata",
"Xerxes",
""
]
] | The branching fraction for the decays of gluinos to third generation quarks is expected to be enhanced in classes of supersymmetric models where either third generation squarks are lighter than other squarks, or in mixed-higgsino dark matter models constructed to be in concordance with the measured density of cold dark matter. In such scenarios, gluino production events at the CERN Large Hadron Collider should be rich in top and bottom quark jets. Requiring b-jets in addition to missing transverse energy should, therefore, enhance the supersymmetry signal relative to Standard Model backgrounds from V + jet, VV and QCD backgrounds (V=W, Z). We quantify the increase in the supersymmetry reach of the LHC from b-tagging in a variety of well-motivated models of supersymmetry. We also explore ``top-tagging'' at the LHC. We find that while the efficiency for this turns out to be too low to give an increase in reach beyond that obtained via b-tagging, top-tagging can indeed provide a confirmatory signal if gluinos are not too heavy. Finally, we explore the prospects for detecting the direct production of third generation squarks in models with an inverted squark mass hierarchy. This is signalled by b-jets + missing transverse energy events harder than in the Standard Model, but softer than those from the production of gluinos and heavier squarks. We find that while these events can be readily separated from SM background (for third generation squark masses ~300-500 GeV), the contamination from the much heavier gluinos and squarks remains formidable if these are also accessible. |
1110.6464 | David Romero Abad | David Romero Abad, Orlando Pereyra Ravinez | Z' boson decay in the SU(3)L \otimes U(1)N electroweak model with heavy
leptons | 5 pages, 2 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Based on the expectation generated by the discovery of new particles by
current colliders, we analyze the decay of the Z' boson in the frame of one of
the SU(3)L \otimes U(1)N electroweak extensions of the standard model. The main
objective is calculate the decay rate of this exotic boson in the
aforementioned model at the tree level. With this purpose we need to develop
the gauge sector, where we find thirty-three interaction terms. Mentioned
particle (Z') has not yet been observed experimentally, but a large number of
models predict its existence. This boson exhibits a variety of decay channels,
but we will concentrate on the bosonic sector, in particular in the new charged
vector bosons V \pm and doubly charged U \pm\pm as final products, because
these are special features of the model. On the other hand, we would like to
remark that this model does not account for the Z' W W vertex although this
decay channel is considered one of the main ways to detect the Z' boson in the
Tevatron.
| [
{
"created": "Fri, 28 Oct 2011 21:17:14 GMT",
"version": "v1"
}
] | 2011-11-01 | [
[
"Abad",
"David Romero",
""
],
[
"Ravinez",
"Orlando Pereyra",
""
]
] | Based on the expectation generated by the discovery of new particles by current colliders, we analyze the decay of the Z' boson in the frame of one of the SU(3)L \otimes U(1)N electroweak extensions of the standard model. The main objective is calculate the decay rate of this exotic boson in the aforementioned model at the tree level. With this purpose we need to develop the gauge sector, where we find thirty-three interaction terms. Mentioned particle (Z') has not yet been observed experimentally, but a large number of models predict its existence. This boson exhibits a variety of decay channels, but we will concentrate on the bosonic sector, in particular in the new charged vector bosons V \pm and doubly charged U \pm\pm as final products, because these are special features of the model. On the other hand, we would like to remark that this model does not account for the Z' W W vertex although this decay channel is considered one of the main ways to detect the Z' boson in the Tevatron. |
1210.7465 | Gilberto Ramalho | G. Ramalho and K. Tsushima | Covariant spectator quark model description of the $\gamma^\ast \Lambda
\to \Sigma^0$ transition | Published version. Updated bibliography. 9 pages | Phys. Rev. D 86, 114030 (2012) | 10.1103/PhysRevD.86.114030 | ADP-12-42/T809 | hep-ph hep-ex hep-lat nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $\gamma^\ast \Lambda \to \Sigma^0$ transition form factors by
applying the covariant spectator quark model. Using the parametrization for the
baryon core wave functions as well as for the pion cloud dressing obtained in a
previous work, we calculate the dependence on the momentum transfer squared,
$Q^2$, of the electromagnetic transition form factors. The magnetic form factor
is dominated by the valence quark contributions. The final result for the
transition magnetic moment, a combination of the quark core and pion cloud
effects, turns out to give a value very close to the data. The pion cloud
contribution, although small, pulls the final result towards the experimental
value The final result, $\mu_{\Lambda\Sigma^0}= -1.486 \mu_N$, is about one and
a half standard deviations from the central value in PDG,
$\mu_{\Lambda\Sigma^0}= -1.61 \pm 0.08 \mu_N$. Thus, a modest improvement in
the statistics of the experiment would permit the confirmation or rejection of
the present result. It is also predicted that small but nonzero values for the
electric form factor in the finite $Q^2$ region, as a consequence of the pion
cloud dressing.
| [
{
"created": "Sun, 28 Oct 2012 14:40:04 GMT",
"version": "v1"
},
{
"created": "Fri, 7 Dec 2012 20:56:37 GMT",
"version": "v2"
},
{
"created": "Fri, 28 Dec 2012 16:03:07 GMT",
"version": "v3"
}
] | 2013-01-01 | [
[
"Ramalho",
"G.",
""
],
[
"Tsushima",
"K.",
""
]
] | We study the $\gamma^\ast \Lambda \to \Sigma^0$ transition form factors by applying the covariant spectator quark model. Using the parametrization for the baryon core wave functions as well as for the pion cloud dressing obtained in a previous work, we calculate the dependence on the momentum transfer squared, $Q^2$, of the electromagnetic transition form factors. The magnetic form factor is dominated by the valence quark contributions. The final result for the transition magnetic moment, a combination of the quark core and pion cloud effects, turns out to give a value very close to the data. The pion cloud contribution, although small, pulls the final result towards the experimental value The final result, $\mu_{\Lambda\Sigma^0}= -1.486 \mu_N$, is about one and a half standard deviations from the central value in PDG, $\mu_{\Lambda\Sigma^0}= -1.61 \pm 0.08 \mu_N$. Thus, a modest improvement in the statistics of the experiment would permit the confirmation or rejection of the present result. It is also predicted that small but nonzero values for the electric form factor in the finite $Q^2$ region, as a consequence of the pion cloud dressing. |
2003.11099 | Michel Luchmann | Gregor Kasieczka, Michel Luchmann, Florian Otterpohl and Tilman Plehn | Per-Object Systematics using Deep-Learned Calibration | null | SciPost Phys. 9, 089 (2020) | 10.21468/SciPostPhys.9.6.089 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show how to treat systematic uncertainties using Bayesian deep networks
for regression. First, we analyze how these networks separately trace
statistical and systematic uncertainties on the momenta of boosted top quarks
forming fat jets. Next, we propose a novel calibration procedure by training on
labels and their error bars. Again, the network cleanly separates the different
uncertainties. As a technical side effect, we show how Bayesian networks can be
extended to describe non-Gaussian features.
| [
{
"created": "Tue, 24 Mar 2020 20:14:46 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Nov 2020 16:45:26 GMT",
"version": "v2"
}
] | 2020-12-23 | [
[
"Kasieczka",
"Gregor",
""
],
[
"Luchmann",
"Michel",
""
],
[
"Otterpohl",
"Florian",
""
],
[
"Plehn",
"Tilman",
""
]
] | We show how to treat systematic uncertainties using Bayesian deep networks for regression. First, we analyze how these networks separately trace statistical and systematic uncertainties on the momenta of boosted top quarks forming fat jets. Next, we propose a novel calibration procedure by training on labels and their error bars. Again, the network cleanly separates the different uncertainties. As a technical side effect, we show how Bayesian networks can be extended to describe non-Gaussian features. |
2107.04053 | Clarissa Siqueira | C. Siqueira, Guilherme N. Fortes, Aion Viana, Farinaldo Queiroz | Indirect Searches for Secluded Dark Matter | 8 pages, 3 figures, talk presented at the 37th ICRC | null | 10.22323/1.395.0577 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Dark matter is one of the most important open problems in particle physics
and cosmology. Weakly interacting massive particles (WIMPs) appear as an
appealing solution, providing the right relic density with a cross-section at
the electroweak scale, however, no WIMP signals were observed until now.
Secluded models are good alternatives to the standard ones. In this case,
instead of a direct annihilation to the standard model (SM) particles, the dark
matter annihilates into mediators which subsequently decay into SM particles.
In this way, secluded models may avoid the stringent limits from direct
searches, and, at the same time, be probed by indirect detection experiments.
Motivated by the appearance of secluded dark matter in several model building
endeavors, in this talk, we will present the sensitivity of several gamma-ray
instruments (current and prospects), including Fermi-LAT, H.E.S.S., CTA, and
SWGO, to secluded dark matter annihilations in the inner galactic halo, and in
the dwarf spheroidal galaxies, covering a wide range dark matter masses, from
tens of GeV to hundreds of TeV.
| [
{
"created": "Thu, 8 Jul 2021 18:05:59 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Sep 2021 18:12:19 GMT",
"version": "v2"
}
] | 2021-10-04 | [
[
"Siqueira",
"C.",
""
],
[
"Fortes",
"Guilherme N.",
""
],
[
"Viana",
"Aion",
""
],
[
"Queiroz",
"Farinaldo",
""
]
] | Dark matter is one of the most important open problems in particle physics and cosmology. Weakly interacting massive particles (WIMPs) appear as an appealing solution, providing the right relic density with a cross-section at the electroweak scale, however, no WIMP signals were observed until now. Secluded models are good alternatives to the standard ones. In this case, instead of a direct annihilation to the standard model (SM) particles, the dark matter annihilates into mediators which subsequently decay into SM particles. In this way, secluded models may avoid the stringent limits from direct searches, and, at the same time, be probed by indirect detection experiments. Motivated by the appearance of secluded dark matter in several model building endeavors, in this talk, we will present the sensitivity of several gamma-ray instruments (current and prospects), including Fermi-LAT, H.E.S.S., CTA, and SWGO, to secluded dark matter annihilations in the inner galactic halo, and in the dwarf spheroidal galaxies, covering a wide range dark matter masses, from tens of GeV to hundreds of TeV. |
hep-ph/9502232 | R. Ramachandran | R. Ramachandran | Spin Puzzle in Nucleon | 12 pages, latex file with one figure (Fig file to be sent separately) | null | null | imsc/94-95/54, IC/94/261 | hep-ph | null | The object of this brief review is to reconcile different points of view on
how the spin of proton is made up from its constituents. On the basis of naive
quark model with flavour symmetry such as isospin or SU(3) one finds a static
description. On the contrary the local SU(3) colour symmetry gives a dynamical
view. Both these views are contrasted and the role of U(1) axial anomaly and
the ambiguity for the measurable spin content is discussed.
| [
{
"created": "Mon, 6 Feb 1995 07:20:34 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Feb 1995 04:49:33 GMT",
"version": "v2"
}
] | 2016-09-01 | [
[
"Ramachandran",
"R.",
""
]
] | The object of this brief review is to reconcile different points of view on how the spin of proton is made up from its constituents. On the basis of naive quark model with flavour symmetry such as isospin or SU(3) one finds a static description. On the contrary the local SU(3) colour symmetry gives a dynamical view. Both these views are contrasted and the role of U(1) axial anomaly and the ambiguity for the measurable spin content is discussed. |
hep-ph/0310197 | Marco Stratmann | Barbara Jager, Stefan Kretzer, Marco Stratmann, Werner Vogelsang | QCD Hard Scattering and the Sign of the Spin Asymmetry A_LL^pi | 4 pages, 3 figures, final version published in PRL (only minor
changes; note: title changed in published version) | Phys.Rev.Lett. 92 (2004) 121803 | 10.1103/PhysRevLett.92.121803 | BNL-NT-03/32, RBRC-359 | hep-ph | null | Recent preliminary PHENIX data are consistent with a negative and sizable
longitudinal double-spin asymmetry A_LL^pi for pi^0 production at moderate
transverse momentum p_perp \simeq 1 - 4 GeV and central rapidity. By means of a
systematic investigation of the relevant degrees of freedom we show that the
perturbative QCD framework at leading power in p_perp produces at best a very
small negative asymmetry in this kinematic range.
| [
{
"created": "Thu, 16 Oct 2003 15:24:07 GMT",
"version": "v1"
},
{
"created": "Wed, 19 May 2004 08:47:50 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Jager",
"Barbara",
""
],
[
"Kretzer",
"Stefan",
""
],
[
"Stratmann",
"Marco",
""
],
[
"Vogelsang",
"Werner",
""
]
] | Recent preliminary PHENIX data are consistent with a negative and sizable longitudinal double-spin asymmetry A_LL^pi for pi^0 production at moderate transverse momentum p_perp \simeq 1 - 4 GeV and central rapidity. By means of a systematic investigation of the relevant degrees of freedom we show that the perturbative QCD framework at leading power in p_perp produces at best a very small negative asymmetry in this kinematic range. |
hep-ph/0611079 | Vassilis Oikonomou | V.K. Oikonomou | Non trivial spacetime effects in a supersymmetric model | 12 pages, 3 figures | J.Phys.A40:9929,2007; J.Phys.A40:9929-9940,2007 | 10.1088/1751-8113/40/32/016 | null | hep-ph | null | We study a ${N=1}$ supersymmetric model in a ${S}^{1}{\times R}^{3}$
spacetime. We find that by choosing appropriate boundary conditions for the
contributing fields supersymmetry can be preserved. However if we add a hard
supersymmetry breaking term, we observe that for small values of the length of
the ${S}^{1}$ dimension, supersymmetry remains unbroken and breaks
spontaneously when the length exceeds a critical value. The final picture
resembles the first order phase transition picture.
| [
{
"created": "Tue, 7 Nov 2006 14:14:35 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Oikonomou",
"V. K.",
""
]
] | We study a ${N=1}$ supersymmetric model in a ${S}^{1}{\times R}^{3}$ spacetime. We find that by choosing appropriate boundary conditions for the contributing fields supersymmetry can be preserved. However if we add a hard supersymmetry breaking term, we observe that for small values of the length of the ${S}^{1}$ dimension, supersymmetry remains unbroken and breaks spontaneously when the length exceeds a critical value. The final picture resembles the first order phase transition picture. |
1704.01107 | Shivaramakrishna Singirala | Shivaramakrishna Singirala, Rukmani Mohanta, Sudhanwa Patra | Singlet scalar Dark matter in $U(1)_{B-L}$ models without right-handed
neutrinos | 26 pages, 11 figures, version to appear in EPJP | null | 10.1140/epjp/i2018-12270-0 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the phenomenology of singlet scalar dark matter in a simple
$B-L$ gauge extension of the Standard Model where the dark matter particle is
charged under the $U(1)_{B-L}$ symmetry. The non-trivial gauge anomalies are
cancelled with the introduction of three exotic fermions with $B-L$ charges as
$-4,-4,5$, instead of right-handed neutrinos $\nu_{Ri}~(i=1,2,3)$ with $B-L=-1$
in conventional $U(1)_{B-L}$ model. Without the need of any ad-hoc discrete
symmetry, the $B-L$ charge plays a crucial role in stabilizing the dark matter.
We make a comprehensive study of dark matter phenomenology in the scalar and
gauge portals separately. In the gauge-mediated regime, we invoke the LEP-II
constraints and dilepton limits of ATLAS on the gauge parameters. A massless
physical Goldstone plays a vital role in the scalar-portal dark matter
observables, becomes a unique feature of the model. We show the mechanism of
generating the light neutrino mass at one-loop level where the dark matter
singlet runs in the loop. We shed light on the semi-annihilation and finally,
we comment on indirect signals in this framework.
| [
{
"created": "Tue, 4 Apr 2017 17:06:10 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Nov 2018 11:30:15 GMT",
"version": "v2"
}
] | 2021-01-12 | [
[
"Singirala",
"Shivaramakrishna",
""
],
[
"Mohanta",
"Rukmani",
""
],
[
"Patra",
"Sudhanwa",
""
]
] | We investigate the phenomenology of singlet scalar dark matter in a simple $B-L$ gauge extension of the Standard Model where the dark matter particle is charged under the $U(1)_{B-L}$ symmetry. The non-trivial gauge anomalies are cancelled with the introduction of three exotic fermions with $B-L$ charges as $-4,-4,5$, instead of right-handed neutrinos $\nu_{Ri}~(i=1,2,3)$ with $B-L=-1$ in conventional $U(1)_{B-L}$ model. Without the need of any ad-hoc discrete symmetry, the $B-L$ charge plays a crucial role in stabilizing the dark matter. We make a comprehensive study of dark matter phenomenology in the scalar and gauge portals separately. In the gauge-mediated regime, we invoke the LEP-II constraints and dilepton limits of ATLAS on the gauge parameters. A massless physical Goldstone plays a vital role in the scalar-portal dark matter observables, becomes a unique feature of the model. We show the mechanism of generating the light neutrino mass at one-loop level where the dark matter singlet runs in the loop. We shed light on the semi-annihilation and finally, we comment on indirect signals in this framework. |
1507.04987 | Masato Yamanaka | Yoshio Koide, Masato Yamanaka, Hiroshi Yokoya | Family Gauge Boson Production at the LHC | 14 pages, 6 figures | null | 10.1016/j.physletb.2015.09.024 | KEK-TH-1851, KIAS-Q15004 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Family gauge boson production at the LHC is investigated according to a
$U(3)$ family gauge model with twisted family number assignment. In the model
we study, a family gauge boson with the lowest mass, $A_1^{\ 1}$, interacts
only with the first generation leptons and the third generation quarks. (The
family numbers are assigned, for example, as $(e_1, e_2, e_3)= (e^-, \mu^-,
\tau^-)$ and $(d_1, d_2, d_3)=(b, d, s) $[or $(d_1, d_2, d_3)=(b, s, d)$]). In
the model, the family gauge coupling constant is fixed by relating to the
electroweak gauge coupling constant. Thus measurements of production cross
sections and branching ratios of $A_1^{\ 1}$ clearly confirm or rule out the
model. We calculate the cross sections of inclusive $A_1^{\ 1}$ production and
$b \bar{b} \, (t \bar{t})$ associated $A_1^{\ 1}$ production at $\sqrt{s} =
14~\text{TeV}$ and $100~\text{TeV}$. With the dielectron production cross
section, we discuss the determination of diagonalizing matrix of quark mass
matrix, $U_{u}$ and $U_{d}$, respectively.
| [
{
"created": "Fri, 17 Jul 2015 14:39:01 GMT",
"version": "v1"
}
] | 2015-09-30 | [
[
"Koide",
"Yoshio",
""
],
[
"Yamanaka",
"Masato",
""
],
[
"Yokoya",
"Hiroshi",
""
]
] | Family gauge boson production at the LHC is investigated according to a $U(3)$ family gauge model with twisted family number assignment. In the model we study, a family gauge boson with the lowest mass, $A_1^{\ 1}$, interacts only with the first generation leptons and the third generation quarks. (The family numbers are assigned, for example, as $(e_1, e_2, e_3)= (e^-, \mu^-, \tau^-)$ and $(d_1, d_2, d_3)=(b, d, s) $[or $(d_1, d_2, d_3)=(b, s, d)$]). In the model, the family gauge coupling constant is fixed by relating to the electroweak gauge coupling constant. Thus measurements of production cross sections and branching ratios of $A_1^{\ 1}$ clearly confirm or rule out the model. We calculate the cross sections of inclusive $A_1^{\ 1}$ production and $b \bar{b} \, (t \bar{t})$ associated $A_1^{\ 1}$ production at $\sqrt{s} = 14~\text{TeV}$ and $100~\text{TeV}$. With the dielectron production cross section, we discuss the determination of diagonalizing matrix of quark mass matrix, $U_{u}$ and $U_{d}$, respectively. |
hep-ph/9509352 | Andreas Laser | H.G. Dosch, J. Kripfganz, A. Laser, M.G. Schmidt | Bound States in the Hot Electroweak Phase | 8 pages, 2 figures; a compressed postscript including the figures is
available at http://www.thphys.uni-heidelberg.de/~laser/hd-thep-95-42.ps.Z | Phys.Lett.B365:213-218,1996 | 10.1016/0370-2693(95)01269-9 | HD-THEP-95-42 | hep-ph | null | The high temperature phase of the electroweak standard theory is described by
a strongly coupled SU(2)-Higgs-model in three dimensions. As in the
Abbott-Farhi-model Higgs and W-boson are low lying bound states. Using a method
by Simonov based on the Feynman-Schwinger representation of correlators we
calculate the masses of these states. Our results are compared with lattice
masses.
| [
{
"created": "Thu, 21 Sep 1995 16:53:51 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Dosch",
"H. G.",
""
],
[
"Kripfganz",
"J.",
""
],
[
"Laser",
"A.",
""
],
[
"Schmidt",
"M. G.",
""
]
] | The high temperature phase of the electroweak standard theory is described by a strongly coupled SU(2)-Higgs-model in three dimensions. As in the Abbott-Farhi-model Higgs and W-boson are low lying bound states. Using a method by Simonov based on the Feynman-Schwinger representation of correlators we calculate the masses of these states. Our results are compared with lattice masses. |
hep-ph/9907382 | Massimo Blasone | Massimo Blasone and Giuseppe Vitiello | Remarks on the neutrino oscillation formula | 10 pages, RevTeX, revised version with comments added | Phys.Rev.D60:111302,1999 | 10.1103/PhysRevD.60.111302 | null | hep-ph | null | We show that the neutrino oscillation formula recently derived in the quantum
field theory framework holds true despite the arbitrariness in the mass
parameter for the flavor fields. This formula is exact and exhibits new
features with respect to the usual Pontecorvo formula, which is however valid
in the relativistic limit.
| [
{
"created": "Thu, 15 Jul 1999 16:45:31 GMT",
"version": "v1"
},
{
"created": "Mon, 16 Aug 1999 17:09:00 GMT",
"version": "v2"
}
] | 2009-12-30 | [
[
"Blasone",
"Massimo",
""
],
[
"Vitiello",
"Giuseppe",
""
]
] | We show that the neutrino oscillation formula recently derived in the quantum field theory framework holds true despite the arbitrariness in the mass parameter for the flavor fields. This formula is exact and exhibits new features with respect to the usual Pontecorvo formula, which is however valid in the relativistic limit. |
2005.04352 | Shaikh Saad | Shaikh Saad | Combined explanations of $(g-2)_{\mu}$, $R_{D^{(\ast)}}$,
$R_{K^{(\ast)}}$ anomalies in a two-loop radiative neutrino mass model | 41 pages, 7 figures. Accepted in Physical Review D | Phys. Rev. D 102, 015019 (2020) | 10.1103/PhysRevD.102.015019 | OSU-HEP-20-04 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the long-standing tension in the muon anomalous magnetic moment
(AMM) and persistent observations of B-physics anomalies in $R_{D^{(\ast)}}$
and $R_{K^{(\ast)}}$ ratios, we construct a simple two-loop radiative neutrino
mass model, and propose a combined explanations of all these apparently
disjoint phenomena within this framework. Our proposed model consists of two
scalar leptoquarks (LQs), a $SU(2)_L$ singlet $S_1\sim (\overline{3},1,1/3)$
and a $SU(2)_L$ triplet $S_3\sim (\overline{3},3,1/3)$ to accommodate
$R_{D^{(\ast)}}$ and $R_{K^{(\ast)}}$ anomalies, respectively. The muon
receives chirality-enhanced contribution towards its $g-2$ due to the presence
of $S_1$ LQ that accounts for the observed deviation from the Standard Model
prediction. Furthermore, we introduce a $SU(2)_L$ singlet scalar diquark
$\omega\sim (\overline{6},1,2/3)$, which is necessary to break lepton number
and generate neutrino mass radiatively with the aid of $S_1$ and $S_3$ LQs. We
perform a detailed phenomenological analysis of this set-up and demonstrate its
viability by providing benchmark points where a fit to the neutrino oscillation
data together with proper explanations of the muon AMM puzzle and flavor
anomalies are accomplished while simultaneously meeting all other flavor
violation and collider bounds.
| [
{
"created": "Sat, 9 May 2020 02:34:20 GMT",
"version": "v1"
},
{
"created": "Fri, 15 May 2020 18:15:39 GMT",
"version": "v2"
},
{
"created": "Thu, 9 Jul 2020 00:30:41 GMT",
"version": "v3"
}
] | 2020-07-29 | [
[
"Saad",
"Shaikh",
""
]
] | Motivated by the long-standing tension in the muon anomalous magnetic moment (AMM) and persistent observations of B-physics anomalies in $R_{D^{(\ast)}}$ and $R_{K^{(\ast)}}$ ratios, we construct a simple two-loop radiative neutrino mass model, and propose a combined explanations of all these apparently disjoint phenomena within this framework. Our proposed model consists of two scalar leptoquarks (LQs), a $SU(2)_L$ singlet $S_1\sim (\overline{3},1,1/3)$ and a $SU(2)_L$ triplet $S_3\sim (\overline{3},3,1/3)$ to accommodate $R_{D^{(\ast)}}$ and $R_{K^{(\ast)}}$ anomalies, respectively. The muon receives chirality-enhanced contribution towards its $g-2$ due to the presence of $S_1$ LQ that accounts for the observed deviation from the Standard Model prediction. Furthermore, we introduce a $SU(2)_L$ singlet scalar diquark $\omega\sim (\overline{6},1,2/3)$, which is necessary to break lepton number and generate neutrino mass radiatively with the aid of $S_1$ and $S_3$ LQs. We perform a detailed phenomenological analysis of this set-up and demonstrate its viability by providing benchmark points where a fit to the neutrino oscillation data together with proper explanations of the muon AMM puzzle and flavor anomalies are accomplished while simultaneously meeting all other flavor violation and collider bounds. |
hep-ph/0105160 | null | Andrzej J. Buras, Andrzej Czarnecki, Mikolaj Misiak, Joerg Urban | Two-Loop Matrix Element of the Current-Current Operator in the Decay B
-> X_s gamma | 18 pages, 6 figures, 1 table | Nucl.Phys.B611:488-502,2001 | 10.1016/S0550-3213(01)00336-4 | null | hep-ph | null | We evaluate the important two-loop matrix element <s gamma| Q_2 | b> of the
operator (cbar gamma^mu P_L b) (sbar gamma_mu P_L b) contributing to the
inclusive radiative decay B -> X_s gamma. The calculation is performed in the
NDR scheme, by means of asymptotic expansions method. The result is given as a
series in z = m_c^2/m_b^2 up to O(z^6). We confirm the result of Greub, Hurth
and Wyler obtained by a different method up to 0(z^3). Higher-order terms are
found to be numerically insignificant.
| [
{
"created": "Wed, 16 May 2001 16:23:22 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Buras",
"Andrzej J.",
""
],
[
"Czarnecki",
"Andrzej",
""
],
[
"Misiak",
"Mikolaj",
""
],
[
"Urban",
"Joerg",
""
]
] | We evaluate the important two-loop matrix element <s gamma| Q_2 | b> of the operator (cbar gamma^mu P_L b) (sbar gamma_mu P_L b) contributing to the inclusive radiative decay B -> X_s gamma. The calculation is performed in the NDR scheme, by means of asymptotic expansions method. The result is given as a series in z = m_c^2/m_b^2 up to O(z^6). We confirm the result of Greub, Hurth and Wyler obtained by a different method up to 0(z^3). Higher-order terms are found to be numerically insignificant. |
hep-ph/0006088 | John F. Donoghue | John F. Donoghue | Random values of the cosmological constant | 17 pages, Comments (and references) added on quantum fluctuations and
eternal inflation, and the discussion of Hubble damping has been modified
significantly | JHEP 0008 (2000) 022 | 10.1088/1126-6708/2000/08/022 | null | hep-ph astro-ph hep-th | null | One way that an anthropic selection mechanism may be manifest in a physical
theory involves multiple domains in the universe with different values of the
physical parameters. If this mechanism is to be relevant for understanding the
small observed value of the cosmological constant, it may involve a mechanism
by which some contributions to the cosmological constant can be fixed at a
continuous range of values in the different domains. I study the properties of
four possible mechanisms, including the possibility of the Hubble damping of a
scalar field with an extremely flat potential. Another interesting possibility
involves fixed random values of non-dynamical form fields, and a cosmological
mechanism is suggested. This case raises the possibility of anthropic selection
of other parameters in addition. Further requirements needed for a consistent
cosmology are discussed.
| [
{
"created": "Fri, 9 Jun 2000 18:26:25 GMT",
"version": "v1"
},
{
"created": "Wed, 21 Jun 2000 15:21:54 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Donoghue",
"John F.",
""
]
] | One way that an anthropic selection mechanism may be manifest in a physical theory involves multiple domains in the universe with different values of the physical parameters. If this mechanism is to be relevant for understanding the small observed value of the cosmological constant, it may involve a mechanism by which some contributions to the cosmological constant can be fixed at a continuous range of values in the different domains. I study the properties of four possible mechanisms, including the possibility of the Hubble damping of a scalar field with an extremely flat potential. Another interesting possibility involves fixed random values of non-dynamical form fields, and a cosmological mechanism is suggested. This case raises the possibility of anthropic selection of other parameters in addition. Further requirements needed for a consistent cosmology are discussed. |
1912.04317 | Lin Dai | Lin Dai, Feng-Kun Guo, Thomas Mehen | Revisiting $X(3872)\to D^0 \bar{D}^0 \pi^0$ in XEFT | null | Phys. Rev. D 101, 054024 (2020) | 10.1103/PhysRevD.101.054024 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The calculation of the decay $X(3872)\to D^0 \bar{D}^0 \pi^0$ in effective
field theory is revisited to include final state $\pi^0 D^0$, $\pi^0
\bar{D}^0$and $D^0\bar{D}^0$ rescattering diagrams. These introduce significant
uncertainty into the prediction for the partial width as a function of the
binding energy. The differential distribution in the pion energy is also
studied for the first time. The normalization of the distribution is again
quite uncertain due to higher order effects but the shape of the distribution
is unaffected by higher order corrections. Furthermore the shape of the
distribution and the location of the peak are sensitive to the binding energy
of $X(3872)$. The shape is strongly impacted by the presence of virtual
$D^{*0}$ graphs which highlights the molecular nature of the $X(3872)$.
Measurement of the pion energy distribution in the decay $X(3872)\to D^0
\bar{D}^0 \pi^0$ can reveal interesting information about the binding nature of
the $X(3872)$.
| [
{
"created": "Mon, 9 Dec 2019 19:02:57 GMT",
"version": "v1"
}
] | 2020-03-25 | [
[
"Dai",
"Lin",
""
],
[
"Guo",
"Feng-Kun",
""
],
[
"Mehen",
"Thomas",
""
]
] | The calculation of the decay $X(3872)\to D^0 \bar{D}^0 \pi^0$ in effective field theory is revisited to include final state $\pi^0 D^0$, $\pi^0 \bar{D}^0$and $D^0\bar{D}^0$ rescattering diagrams. These introduce significant uncertainty into the prediction for the partial width as a function of the binding energy. The differential distribution in the pion energy is also studied for the first time. The normalization of the distribution is again quite uncertain due to higher order effects but the shape of the distribution is unaffected by higher order corrections. Furthermore the shape of the distribution and the location of the peak are sensitive to the binding energy of $X(3872)$. The shape is strongly impacted by the presence of virtual $D^{*0}$ graphs which highlights the molecular nature of the $X(3872)$. Measurement of the pion energy distribution in the decay $X(3872)\to D^0 \bar{D}^0 \pi^0$ can reveal interesting information about the binding nature of the $X(3872)$. |
hep-ph/0601126 | Mu-Chun Chen | Mu-Chun Chen | Models of Little Higgs and Electroweak Precision Tests | 16 pages; 4 figures; review submitted to Modern Physics Letter A | Mod.Phys.Lett.A21:621-638,2006 | 10.1142/S0217732306020020 | FERMILAB-PUB-05-554-T | hep-ph | null | The little Higgs idea is an alternative to supersymmetry as a solution to the
gauge hierarchy problem. In this note, I review various little Higgs models and
their phenomenology with emphases on the precision electroweak constraints in
these models.
| [
{
"created": "Mon, 16 Jan 2006 23:50:14 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Chen",
"Mu-Chun",
""
]
] | The little Higgs idea is an alternative to supersymmetry as a solution to the gauge hierarchy problem. In this note, I review various little Higgs models and their phenomenology with emphases on the precision electroweak constraints in these models. |
1902.03243 | Andrew Fowlie Assoc. Prof. | Andrew Fowlie | Bayesian and frequentist approaches to resonance searches | 12 pages, 11 figures, edited & expanded, includes discussion of
Jeffreys-Lindley paradox, but conclusions unchanged | null | 10.1088/1748-0221/14/10/P10031 | null | hep-ph hep-ex physics.data-an | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate Bayesian and frequentist approaches to resonance searches
using a toy model based on an ATLAS search for the Higgs boson in the diphoton
channel. We draw pseudo-data from the background only model and background plus
signal model at multiple luminosities, from $10^{-3}$/fb to $10^7$/fb. We chart
the change in the Bayesian posterior of the background only model and the
global p-value. We find that, as anticipated, the posterior converges to
certainty about the model as luminosity increases. The p-value, on the other
hand, randomly walks between 0 and 1 if the background only model is true, and
otherwise converges to 0. After briefly commenting on the frequentist
properties of the posterior, we make a direct comparison of the significances
obtained in Bayesian and frequentist frameworks. We find that the well-known
look-elsewhere effect reduces local significances by about 1$\sigma$. We
furthermore find that significances from our Bayesian framework are typically
about 1 to 2$\sigma$ smaller than the global significances, though the
reduction depends on the prior, global significance and integrated luminosity.
This suggests that even global significances could significantly overstate the
evidence against the background only model. We checked that this effect --- the
Bayes effect --- was robust with respect to fourteen choices of prior and
investigated the Jeffreys-Lindley paradox for three of them.
| [
{
"created": "Fri, 8 Feb 2019 19:00:01 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Oct 2019 07:52:13 GMT",
"version": "v2"
}
] | 2019-10-24 | [
[
"Fowlie",
"Andrew",
""
]
] | We investigate Bayesian and frequentist approaches to resonance searches using a toy model based on an ATLAS search for the Higgs boson in the diphoton channel. We draw pseudo-data from the background only model and background plus signal model at multiple luminosities, from $10^{-3}$/fb to $10^7$/fb. We chart the change in the Bayesian posterior of the background only model and the global p-value. We find that, as anticipated, the posterior converges to certainty about the model as luminosity increases. The p-value, on the other hand, randomly walks between 0 and 1 if the background only model is true, and otherwise converges to 0. After briefly commenting on the frequentist properties of the posterior, we make a direct comparison of the significances obtained in Bayesian and frequentist frameworks. We find that the well-known look-elsewhere effect reduces local significances by about 1$\sigma$. We furthermore find that significances from our Bayesian framework are typically about 1 to 2$\sigma$ smaller than the global significances, though the reduction depends on the prior, global significance and integrated luminosity. This suggests that even global significances could significantly overstate the evidence against the background only model. We checked that this effect --- the Bayes effect --- was robust with respect to fourteen choices of prior and investigated the Jeffreys-Lindley paradox for three of them. |
2011.01362 | Timur Bikbaev Eduardovich | T.E. Bikbaev (1), M.Yu. Khlopov (1, 2 and 3), A.G. Mayorov (1) ((1)
National Research Nuclear University MEPhI (Moscow Engineering Physics
Institute), Moscow, Russia, (2) Institute of Physics, Southern Federal
University, Rostov on Don, Russia, (3) Universit\'e de Paris, CNRS,
Astroparticule et Cosmologie, Paris, France) | Numerical simulation of dark atom interaction with nuclei | Prepared for Proceedings of XXIII Bled Workshop "What comes beyond
the Standard models?" | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The old and still not solved problem of dark atom solution for the puzzles of
direct dark matter searches is related with rigorous prove of the existence of
a low energy bound state in the dark atom interaction with nuclei. Such prove
must involve a self-consistent account of the nuclear attraction and Coulomb
repulsion in such interaction. In the lack of usual small parameters of atomic
physics like smallness of electromagnetic coupling of the electronic shell or
smallness of the size of nucleus as compared with the radius of the Bohr orbit
the rigorous study of this problem inevitably implies numerical simulation of
dark atom interaction with nuclei. Our approach to such simulations of
$OHe-$nucleus interaction involves multi-step approximation to the realistic
picture by continuous addition to the initially classical picture of three
point-like body problem essential quantum mechanical features.
| [
{
"created": "Mon, 2 Nov 2020 22:38:41 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Nov 2020 09:44:05 GMT",
"version": "v2"
}
] | 2020-11-06 | [
[
"Bikbaev",
"T. E.",
"",
"1, 2 and 3"
],
[
"Khlopov",
"M. Yu.",
"",
"1, 2 and 3"
],
[
"Mayorov",
"A. G.",
""
]
] | The old and still not solved problem of dark atom solution for the puzzles of direct dark matter searches is related with rigorous prove of the existence of a low energy bound state in the dark atom interaction with nuclei. Such prove must involve a self-consistent account of the nuclear attraction and Coulomb repulsion in such interaction. In the lack of usual small parameters of atomic physics like smallness of electromagnetic coupling of the electronic shell or smallness of the size of nucleus as compared with the radius of the Bohr orbit the rigorous study of this problem inevitably implies numerical simulation of dark atom interaction with nuclei. Our approach to such simulations of $OHe-$nucleus interaction involves multi-step approximation to the realistic picture by continuous addition to the initially classical picture of three point-like body problem essential quantum mechanical features. |
1011.0013 | Sannino Francesco | Mads T. Frandsen, Isabella Masina, Francesco Sannino | Cosmic Sum Rules | RevTeX, 4 pages, 6 figures, two-columns. Final version to match the
published version in Brief Reports section of Phys. Rev. D. We stress that
this is the first paper about charge asymmetries in cosmic rays | Phys.Rev.D83:127301,2011 | 10.1103/PhysRevD.83.127301 | CP3-Origins-2010-48 | hep-ph astro-ph.HE gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We introduce new sum rules allowing to determine universal properties of the
unknown component of the cosmic rays and show how they can be used to predict
the positron fraction at energies not yet explored by current experiments and
to constrain specific models.
| [
{
"created": "Fri, 29 Oct 2010 20:47:11 GMT",
"version": "v1"
},
{
"created": "Mon, 23 May 2011 20:17:40 GMT",
"version": "v2"
}
] | 2015-03-17 | [
[
"Frandsen",
"Mads T.",
""
],
[
"Masina",
"Isabella",
""
],
[
"Sannino",
"Francesco",
""
]
] | We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how they can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models. |
1310.0823 | Javier Redondo | Javier Redondo | Solar axion flux from the axion-electron coupling | 24 pages, 9 figures. Data points for the solar-axion flux are
provided in the file gaeflux.dat uploaded with the paper | null | 10.1088/1475-7516/2013/12/008 | MPP-2011-219 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In non-hadronic axion models, where axions couple to electrons at tree level,
the solar axion flux is completely dominated by the ABC reactions (Atomic
recombination and deexcitation, Bremsstrahlung and Compton). In this paper the
ABC flux is computed from available libraries of monochromatic photon radiative
opacities (OP, LEDCOP and OPAS) by exploiting the relations between axion and
photon emission cross sections. These results turn to be ~ 30% larger than
previous estimates due to atomic recombination (free-bound electron
transitions) and deexcitation (bound-bound), which where not previously taken
into account.
| [
{
"created": "Wed, 2 Oct 2013 20:00:04 GMT",
"version": "v1"
}
] | 2015-06-17 | [
[
"Redondo",
"Javier",
""
]
] | In non-hadronic axion models, where axions couple to electrons at tree level, the solar axion flux is completely dominated by the ABC reactions (Atomic recombination and deexcitation, Bremsstrahlung and Compton). In this paper the ABC flux is computed from available libraries of monochromatic photon radiative opacities (OP, LEDCOP and OPAS) by exploiting the relations between axion and photon emission cross sections. These results turn to be ~ 30% larger than previous estimates due to atomic recombination (free-bound electron transitions) and deexcitation (bound-bound), which where not previously taken into account. |
1411.2097 | Kiyoharu Kawana | Kiyoharu Kawana | Multiple Point Principle of the Standard Model with Scalar Singlet Dark
Matter and Right Handed Neutrinos | 16 pages, 4 figures; references added, Version to appear in PTEP(v2) | Prog. Theor. Exp. Phys. (2015) 023B04 | 10.1093/ptep/ptv006 | KUNS-2528 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the multiple point principle (MPP) of the Standard Model (SM)
with the scalar singlet Dark Matter (DM) and three heavy right-handed neutrinos
at the scale where the beta function $\beta_{\lambda}$ of the effective Higgs
self coupling $\lambda_{\text{eff}}$ becomes zero. We make the two-loop
analysis and find that the top quark mass $M_{t}$ and the Higgs portal coupling
$\kappa$ are strongly related each other. One of the good points in this model
is that the larger $M_{t}{1mm}(\gtrsim 171\text{GeV})$ is allowed. This fact is
consistent with the recent experimental value \cite{ATLAS:2014wva}
$M_{t}=173.34\pm0.76$ GeV, which corresponds to the DM mass
$769{1mm}\text{GeV}\leq m_{\text{DM}}\leq 1053 {1mm}\text{GeV}$.
| [
{
"created": "Sat, 8 Nov 2014 09:27:03 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Feb 2015 14:06:35 GMT",
"version": "v2"
}
] | 2015-02-26 | [
[
"Kawana",
"Kiyoharu",
""
]
] | We consider the multiple point principle (MPP) of the Standard Model (SM) with the scalar singlet Dark Matter (DM) and three heavy right-handed neutrinos at the scale where the beta function $\beta_{\lambda}$ of the effective Higgs self coupling $\lambda_{\text{eff}}$ becomes zero. We make the two-loop analysis and find that the top quark mass $M_{t}$ and the Higgs portal coupling $\kappa$ are strongly related each other. One of the good points in this model is that the larger $M_{t}{1mm}(\gtrsim 171\text{GeV})$ is allowed. This fact is consistent with the recent experimental value \cite{ATLAS:2014wva} $M_{t}=173.34\pm0.76$ GeV, which corresponds to the DM mass $769{1mm}\text{GeV}\leq m_{\text{DM}}\leq 1053 {1mm}\text{GeV}$. |
hep-ph/0509370 | Davide Meloni | D. Meloni | The measurement of $\theta_{13}$ and $\delta$: the role of the
uncertainties on the solar and atmospheric parameters | 2 pages, 1 epsfig; NUFACT'05, 21-26 June 2005, Frascati | null | 10.1016/j.nuclphysbps.2006.02.038 | null | hep-ph | null | In this talk we show how the errors on solar and atmospheric parameters
affect the measurement of the unknown PMNS parameters $\theta_{13}$ and
$\delta$ at future LBL facilities. Performing three parameters fits in
$\theta_{13}$, $\delta$ and, in turn, one of the atmospheric or solar
parameters, we show that present uncertainties on $\theta_{23}$ and $\Delta
m^2_{23}$ worsen significantly the precision on ($\theta_{13}$,$\delta$)
whereas the solar sector does not introduce further uncertainties. A precision
on the atmospheric parameters similar to what expected at T2K-I is necessary to
improve the sensitivities to $\theta_{13}$ and $\delta$.
| [
{
"created": "Fri, 30 Sep 2005 16:18:25 GMT",
"version": "v1"
}
] | 2009-11-11 | [
[
"Meloni",
"D.",
""
]
] | In this talk we show how the errors on solar and atmospheric parameters affect the measurement of the unknown PMNS parameters $\theta_{13}$ and $\delta$ at future LBL facilities. Performing three parameters fits in $\theta_{13}$, $\delta$ and, in turn, one of the atmospheric or solar parameters, we show that present uncertainties on $\theta_{23}$ and $\Delta m^2_{23}$ worsen significantly the precision on ($\theta_{13}$,$\delta$) whereas the solar sector does not introduce further uncertainties. A precision on the atmospheric parameters similar to what expected at T2K-I is necessary to improve the sensitivities to $\theta_{13}$ and $\delta$. |
0910.2314 | Kenji Nishiwaki | C. S. Lim, Nobuhito Maru, and Kenji Nishiwaki | CP Violation due to Compactification | 22 pages, 6 figures, Final version to appear in PRD | Phys.Rev.D81:076006,2010 | 10.1103/PhysRevD.81.076006 | KOBE-TH-09-09 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We address the challenging issue of how CP violation is realized in higher
dimensional gauge theories without higher dimensional elementary scalar fields.
In such theories interactions are basically governed by a gauge principle and
therefore to get CP violating phases is a non-trivial task. It is demonstrated
that CP violation is achieved as the result of compactification of extra
dimensions, which is incompatible with the 4-dimensional CP transformation. As
a simple example we adopt a 6-dimensional U(1) model compactified on a
2-dimensional orbifold $T^{2}/Z_{4}$. We argue that the 4-dimensional CP
transformation is related to the complex structure of the extra space and show
how the $Z_{4}$ orbifolding leads to CP violation. We confirm by explicit
calculation of the interaction vertices that CP violating phases remain even
after the re-phasing of relevant fields. For completeness, we derive a
re-phasing invariant CP violating quantity, following a similar argument in the
Kobayashi-Maskawa model which led to the Jarlskog parameter. As an example of a
CP violating observable we briefly comment on the electric dipole moment of the
electron.
| [
{
"created": "Tue, 13 Oct 2009 16:16:50 GMT",
"version": "v1"
},
{
"created": "Sun, 28 Mar 2010 12:47:39 GMT",
"version": "v2"
}
] | 2010-05-12 | [
[
"Lim",
"C. S.",
""
],
[
"Maru",
"Nobuhito",
""
],
[
"Nishiwaki",
"Kenji",
""
]
] | We address the challenging issue of how CP violation is realized in higher dimensional gauge theories without higher dimensional elementary scalar fields. In such theories interactions are basically governed by a gauge principle and therefore to get CP violating phases is a non-trivial task. It is demonstrated that CP violation is achieved as the result of compactification of extra dimensions, which is incompatible with the 4-dimensional CP transformation. As a simple example we adopt a 6-dimensional U(1) model compactified on a 2-dimensional orbifold $T^{2}/Z_{4}$. We argue that the 4-dimensional CP transformation is related to the complex structure of the extra space and show how the $Z_{4}$ orbifolding leads to CP violation. We confirm by explicit calculation of the interaction vertices that CP violating phases remain even after the re-phasing of relevant fields. For completeness, we derive a re-phasing invariant CP violating quantity, following a similar argument in the Kobayashi-Maskawa model which led to the Jarlskog parameter. As an example of a CP violating observable we briefly comment on the electric dipole moment of the electron. |
2402.17344 | Raghunath Sahoo | Bhagyarathi Sahoo, Captain R. Singh, and Raghunath Sahoo | Impact of strong magnetic field, baryon chemical potential, and medium
anisotropy on polarization and spin alignment of hadrons | 13 pages and 8-captioned figures. Submitted for publication | null | null | null | hep-ph hep-ex hep-th nucl-ex nucl-th | http://creativecommons.org/licenses/by-sa/4.0/ | The recent observation of global polarization of $\Lambda$ ($\bar{\Lambda}$)
hyperons and spin alignment of $\phi$ and $K^{*0}$ vector mesons create
remarkable interest in investigating the particle polarization in the
relativistic fluid produced in heavy-ion collisions at GeV/TeV energies. Among
other sources of polarization, the Debye mass of a medium plays a crucial role
in particle polarization. Any modification brought to the effective mass due to
the temperature, strong magnetic field (eB), baryonic chemical potential
($\mu_{B}$), and medium anisotropy ($\xi$), vorticity, etc., certainly affects
the particle polarization. In this work, we explore the global hyperon
polarization and the spin alignment of vector mesons corresponding to the
strong magnetic field, baryonic chemical potential, and medium anisotropy. We
find that the degree of polarization is flavor-dependent for hyperons.
Meanwhile, vector meson spin alignment depends on the hadronization mechanisms
of initially polarized quarks and anti-quarks. Medium anisotropy significantly
changes the degree of polarization in comparison with the magnetic field and
baryon chemical potential.
| [
{
"created": "Tue, 27 Feb 2024 09:23:17 GMT",
"version": "v1"
}
] | 2024-02-28 | [
[
"Sahoo",
"Bhagyarathi",
""
],
[
"Singh",
"Captain R.",
""
],
[
"Sahoo",
"Raghunath",
""
]
] | The recent observation of global polarization of $\Lambda$ ($\bar{\Lambda}$) hyperons and spin alignment of $\phi$ and $K^{*0}$ vector mesons create remarkable interest in investigating the particle polarization in the relativistic fluid produced in heavy-ion collisions at GeV/TeV energies. Among other sources of polarization, the Debye mass of a medium plays a crucial role in particle polarization. Any modification brought to the effective mass due to the temperature, strong magnetic field (eB), baryonic chemical potential ($\mu_{B}$), and medium anisotropy ($\xi$), vorticity, etc., certainly affects the particle polarization. In this work, we explore the global hyperon polarization and the spin alignment of vector mesons corresponding to the strong magnetic field, baryonic chemical potential, and medium anisotropy. We find that the degree of polarization is flavor-dependent for hyperons. Meanwhile, vector meson spin alignment depends on the hadronization mechanisms of initially polarized quarks and anti-quarks. Medium anisotropy significantly changes the degree of polarization in comparison with the magnetic field and baryon chemical potential. |
hep-ph/0111359 | Daniela Bortoletto | The CDF collaboration | Measurement of the $B^+$ Total Cross Section and $B^+$ Differential
Cross Section $d\sigma/dp_T$ in $p \bar p $ Collisions at $\sqrt{s}=1.8$ TeV | null | Phys.Rev.D65:052005,2002 | 10.1103/PhysRevD.65.052005 | FERMILAB-PUB-01/347-E | hep-ph | null | We present measurements of the B+ meson total cross section and differential
cross section $d\sigma/ dp_T$. The measurements use a $98\pm 4$ pb^{-1} sample
of $p \bar p$ collisions at $\sqrt{s}=1.8$ TeV collected by the CDF detector.
Charged $B$ meson candidates are reconstructed through the decay $B^{\pm} \to
J/\psi K^{\pm}$ with $J/\psi\to \mu^+ \mu^-$. The total cross section, measured
in the central rapidity region $|y|<1.0$ for $p_T(B)>6.0$ GeV/$c$, is $3.6 \pm
0.6 ({\rm stat} \oplus {\rm syst)} \mu$b. The measured differential cross
section is substantially larger than typical QCD predictions calculated to
next-to-leading order.
| [
{
"created": "Tue, 27 Nov 2001 21:58:51 GMT",
"version": "v1"
}
] | 2012-08-27 | [
[
"The CDF collaboration",
"",
""
]
] | We present measurements of the B+ meson total cross section and differential cross section $d\sigma/ dp_T$. The measurements use a $98\pm 4$ pb^{-1} sample of $p \bar p$ collisions at $\sqrt{s}=1.8$ TeV collected by the CDF detector. Charged $B$ meson candidates are reconstructed through the decay $B^{\pm} \to J/\psi K^{\pm}$ with $J/\psi\to \mu^+ \mu^-$. The total cross section, measured in the central rapidity region $|y|<1.0$ for $p_T(B)>6.0$ GeV/$c$, is $3.6 \pm 0.6 ({\rm stat} \oplus {\rm syst)} \mu$b. The measured differential cross section is substantially larger than typical QCD predictions calculated to next-to-leading order. |
hep-ph/9707291 | Johan Bijnens | J. Bijnens, G. Colangelo, G. Ecker, J. Gasser and M.E. Sainio | Pion-pion scattering at low energy | LaTeX, uses epsf.sty, 10 figures, 52 pages | Nucl.Phys. B508 (1997) 263-310; Erratum-ibid. B517 (1998) 639 | 10.1016/S0550-3213(97)00621-4 | LU/TP 97-14, UWThPh-1997-15, BUTP-97/17, HIP-1997-31/TH | hep-ph | null | We present technical details of the evaluation of the elastic pi-pi
scattering amplitude to two loops in chiral perturbation theory. In particular,
we elaborate on the renormalization procedure at the two-loop order and on the
evaluation of the relevant Feynman diagrams that can all be expressed in terms
of elementary functions. For the sake of clarity, we discuss these matters both
in the N-component $\phi^4$ theory (in its symmetric phase) and in chiral
perturbation theory. Estimates for the relevant low-energy constants of
$O(p^6)$ are presented. Threshold parameters and phase shifts are then
calculated for two sets of $O(p^4)$ coupling constants and compared with
experiment. We comment on the extraction of threshold parameters from phase
shift data.
| [
{
"created": "Wed, 9 Jul 1997 09:48:24 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Bijnens",
"J.",
""
],
[
"Colangelo",
"G.",
""
],
[
"Ecker",
"G.",
""
],
[
"Gasser",
"J.",
""
],
[
"Sainio",
"M. E.",
""
]
] | We present technical details of the evaluation of the elastic pi-pi scattering amplitude to two loops in chiral perturbation theory. In particular, we elaborate on the renormalization procedure at the two-loop order and on the evaluation of the relevant Feynman diagrams that can all be expressed in terms of elementary functions. For the sake of clarity, we discuss these matters both in the N-component $\phi^4$ theory (in its symmetric phase) and in chiral perturbation theory. Estimates for the relevant low-energy constants of $O(p^6)$ are presented. Threshold parameters and phase shifts are then calculated for two sets of $O(p^4)$ coupling constants and compared with experiment. We comment on the extraction of threshold parameters from phase shift data. |
1001.2075 | Yoshio Koide | Yoshio Koide | Yukawaon model and unified description of quark and lepton mass matrices | 4 pages, to appear in Proceedings of Lepton-Photon 2009 | null | null | OU-HET-652/2010 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In the so-called yukawaon model, where effective Yukawa coupling constants
Y_f^{eff} (f=e,\nu,u,d) are given by vacuum expectation values of gauge singlet
scalars (yukawaons) Y_f with 3\times 3 flavor components, it is tried to give a
unified description of quark and lepton mass matrices. Especially, without
assuming any discrete symmetry in the lepton sector, nearly tribimaximal mixing
is derived by assumed a simple up-quark mass matrix form.
| [
{
"created": "Wed, 13 Jan 2010 04:55:22 GMT",
"version": "v1"
}
] | 2010-01-14 | [
[
"Koide",
"Yoshio",
""
]
] | In the so-called yukawaon model, where effective Yukawa coupling constants Y_f^{eff} (f=e,\nu,u,d) are given by vacuum expectation values of gauge singlet scalars (yukawaons) Y_f with 3\times 3 flavor components, it is tried to give a unified description of quark and lepton mass matrices. Especially, without assuming any discrete symmetry in the lepton sector, nearly tribimaximal mixing is derived by assumed a simple up-quark mass matrix form. |
2312.11704 | Sampsa Vihonen | Hai-Xing Lin, Jian Tang and Sampsa Vihonen | Ultralight dark matter in neutrino oscillations to accommodate T2K and
NO$\nu$A tension | 20 pages, 7 figures and 1 table | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | Ultralight dark matter with neutrino couplings is investigated in light of
the long-baseline neutrino oscillation data in T2K and NO$\nu$A experiments.
The observed tension between T2K and NO$\nu$A is shown to be ameliorated when
ultralight dark matter of either scalar or vector form is taken into
consideration. The best result is achieved with scalar dark matter which can
alleviate the tension by 2.0$\sigma$ CL with flavour-universal couplings. We
also consider scalar dark matter with flavour-general couplings and vector dark
matter in $L_e - L_\mu$ and $L_\mu - L_\tau$ cases. It is shown in all cases
that the tension is relaxed by approximately 1.5$\sigma$-2.0$\sigma$ CL while
the current experimental constraints can be evaded.
| [
{
"created": "Mon, 18 Dec 2023 21:04:37 GMT",
"version": "v1"
}
] | 2023-12-20 | [
[
"Lin",
"Hai-Xing",
""
],
[
"Tang",
"Jian",
""
],
[
"Vihonen",
"Sampsa",
""
]
] | Ultralight dark matter with neutrino couplings is investigated in light of the long-baseline neutrino oscillation data in T2K and NO$\nu$A experiments. The observed tension between T2K and NO$\nu$A is shown to be ameliorated when ultralight dark matter of either scalar or vector form is taken into consideration. The best result is achieved with scalar dark matter which can alleviate the tension by 2.0$\sigma$ CL with flavour-universal couplings. We also consider scalar dark matter with flavour-general couplings and vector dark matter in $L_e - L_\mu$ and $L_\mu - L_\tau$ cases. It is shown in all cases that the tension is relaxed by approximately 1.5$\sigma$-2.0$\sigma$ CL while the current experimental constraints can be evaded. |
hep-ph/0103158 | Grzegorz Wilk | O.V.Utyuzh, G.Wilk and Z.Wlodarczyk | Limitations of the $\Phi$ measure of fluctuations in event-by-event
analysis | LaTex file, 3 eps files with figures and psfig.sty file; 12 pages
altogether; corrected version (with changed title); to be published in Phys.
Rev. C | Phys.Rev.C64:027901,2001 | 10.1103/PhysRevC.64.027901 | null | hep-ph nucl-th | null | We provide a critical overview of the $\Phi$ measure of fluctuations and
correlations. In particular we show that its discriminating power is rather
limited in situations encountered in experiment.
| [
{
"created": "Wed, 14 Mar 2001 14:21:53 GMT",
"version": "v1"
},
{
"created": "Fri, 1 Jun 2001 12:30:29 GMT",
"version": "v2"
}
] | 2009-04-15 | [
[
"Utyuzh",
"O. V.",
""
],
[
"Wilk",
"G.",
""
],
[
"Wlodarczyk",
"Z.",
""
]
] | We provide a critical overview of the $\Phi$ measure of fluctuations and correlations. In particular we show that its discriminating power is rather limited in situations encountered in experiment. |
hep-ph/9506226 | Paolo Nason | S. Frixione, P. Nason and G. Ridolfi | Differential Distributions for Heavy Flavour Production at HERA | 25 pages, Latex, epsfig, 19 tar-gzip-uuencoded figures. Also
available from http://surya11.cern.ch/users/nason/misc | Nucl.Phys.B454:3-24,1995 | 10.1016/0550-3213(95)00445-X | CERN-TH/95-143, GeF-TH-5/1995, IFUM 506/FT | hep-ph | null | We compute pseudorapidity and transverse momentum distributions for charm and
bottom production at HERA. We examine the effect of next-to-leading order QCD
corrections, the effect of possible intrinsic transverse momenta of the
incoming partons, and of fragmentation. We compare our results with full Monte
Carlo simulation using HERWIG. The importance of the hadronic component of the
photon is also studied. We examine the possibility to distinguish among
different parametrizations of the photon parton densities using charm
production data, and the possibilty to extract information about the small-$x$
behaviour of the gluon density of the proton. We also give a prediction for the
transverse momentum and pseudorapidity distributions for bottom production at
HERA.
| [
{
"created": "Fri, 2 Jun 1995 16:18:34 GMT",
"version": "v1"
},
{
"created": "Mon, 5 Jun 1995 21:44:16 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Frixione",
"S.",
""
],
[
"Nason",
"P.",
""
],
[
"Ridolfi",
"G.",
""
]
] | We compute pseudorapidity and transverse momentum distributions for charm and bottom production at HERA. We examine the effect of next-to-leading order QCD corrections, the effect of possible intrinsic transverse momenta of the incoming partons, and of fragmentation. We compare our results with full Monte Carlo simulation using HERWIG. The importance of the hadronic component of the photon is also studied. We examine the possibility to distinguish among different parametrizations of the photon parton densities using charm production data, and the possibilty to extract information about the small-$x$ behaviour of the gluon density of the proton. We also give a prediction for the transverse momentum and pseudorapidity distributions for bottom production at HERA. |
1409.1435 | Johannes Bl\"umlein | J. Ablinger, J. Bl\"umlein, A. De Freitas, A. Hasselhuhn, A. von
Manteuffel, M. Round and C. Schneider | 3-loop Massive $O(T_F^2)$ Contributions to the DIS Operator Matrix
Element $A_{gg}$ | 4 pages, Contribution to the Proceedings of QCD '14, Montpellier,
July 2014 | null | null | DESY 14--152, DO--TH 14/20, SFB/CPP--14--67 , LPN 14--110 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Contributions to heavy flavour transition matrix elements in the variable
flavour number scheme are considered at 3-loop order. In particular a
calculation of the diagrams with two equal masses that contribute to the
massive operator matrix element $A_{gg,Q}^{(3)}$ is performed. In the Mellin
space result one finds finite nested binomial sums. In $x$-space these sums
correspond to iterated integrals over an alphabet containing also square-root
valued letters.
| [
{
"created": "Thu, 4 Sep 2014 13:23:02 GMT",
"version": "v1"
}
] | 2014-09-05 | [
[
"Ablinger",
"J.",
""
],
[
"Blümlein",
"J.",
""
],
[
"De Freitas",
"A.",
""
],
[
"Hasselhuhn",
"A.",
""
],
[
"von Manteuffel",
"A.",
""
],
[
"Round",
"M.",
""
],
[
"Schneider",
"C.",
""
]
] | Contributions to heavy flavour transition matrix elements in the variable flavour number scheme are considered at 3-loop order. In particular a calculation of the diagrams with two equal masses that contribute to the massive operator matrix element $A_{gg,Q}^{(3)}$ is performed. In the Mellin space result one finds finite nested binomial sums. In $x$-space these sums correspond to iterated integrals over an alphabet containing also square-root valued letters. |
hep-ph/0501139 | Roman Nevzorov | D.J.Miller, S.Moretti, R.Nevzorov | Higgs bosons in the NMSSM with exact and slightly broken PQ-symmetry | Prepared for 18th International Workshop on High Energy Physics and
Quantum Field Theory (QFTHEP 2004), St.Petersburg, Russia, 17-23 June 2004 | null | null | SHEP-05-01 | hep-ph | null | We explore the Higgs sector of the NMSSM in the limit when the Peccei--Quinn
symmetry is exact or only slightly broken. In this case the Higgs spectrum has
a hierarchical structure which is caused by the stability of the physical
vacuum. We find a strong correlation between the parameters of the NMSSM if
$\kappa=0$ or $\kappa\lesssim \lambda^2$. It allows one to distinguish the
NMSSM with exact or softly broken PQ-symmetry from the MSSM even when extra
scalar and pseudoscalar Higgs states escape direct detection.
| [
{
"created": "Sat, 15 Jan 2005 16:14:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Miller",
"D. J.",
""
],
[
"Moretti",
"S.",
""
],
[
"Nevzorov",
"R.",
""
]
] | We explore the Higgs sector of the NMSSM in the limit when the Peccei--Quinn symmetry is exact or only slightly broken. In this case the Higgs spectrum has a hierarchical structure which is caused by the stability of the physical vacuum. We find a strong correlation between the parameters of the NMSSM if $\kappa=0$ or $\kappa\lesssim \lambda^2$. It allows one to distinguish the NMSSM with exact or softly broken PQ-symmetry from the MSSM even when extra scalar and pseudoscalar Higgs states escape direct detection. |
2202.10779 | Maryam Soleymaninia | Maryam Soleymaninia, Hadi Hashamipour, Hamzeh Khanpour | Neural Network QCD analysis of charged hadron Fragmentation Functions in
the presence of SIDIS data | 18 pages, 8 figures, and 1 table | Phys.Rev.D 105 (2022) 11, 114018 | 10.1103/PhysRevD.105.114018 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we present a QCD analysis to extract the Fragmentation
Functions (FFs) of unidentified light charged hadron entitled as SHK22.h from
high-energy lepton-lepton annihilation and lepton-hadron scattering data sets.
This analysis includes the data from all available single inclusive
electron-positron annihilation (SIA) processes and semi-inclusive
deep-inelastic scattering (SIDIS) measurements for the unidentified light
charged hadron productions. The SIDIS data which has been measured by the
COMPASS experiment could allow the flavor dependence of the FFs to be well
constrained. We exploit the analytic derivative of the Neural Network (NN) for
fitting of FFs at next-to-leading-order (NLO) accuracy in the perturbative QCD
(pQCD). The Monte Carlo method is implied for all sources of experimental
uncertainties and the Parton distribution functions (PDFs) as well. Very good
agreements are achieved between the SHK22.h FFs set and the most recent QCD
fits available in literature, namely JAM20 and NNFF1.1h. In addition, we
discuss the impact arising from the inclusion of SIDIS data on the extracted
light-charged hadron FFs. The global QCD resulting at NLO for charged hadron
FFs provides valuable insights for applications in present and future
high-energy measurement of charged hadron final state processes.
| [
{
"created": "Tue, 22 Feb 2022 10:02:54 GMT",
"version": "v1"
},
{
"created": "Sat, 2 Jul 2022 07:00:22 GMT",
"version": "v2"
}
] | 2022-07-05 | [
[
"Soleymaninia",
"Maryam",
""
],
[
"Hashamipour",
"Hadi",
""
],
[
"Khanpour",
"Hamzeh",
""
]
] | In this paper, we present a QCD analysis to extract the Fragmentation Functions (FFs) of unidentified light charged hadron entitled as SHK22.h from high-energy lepton-lepton annihilation and lepton-hadron scattering data sets. This analysis includes the data from all available single inclusive electron-positron annihilation (SIA) processes and semi-inclusive deep-inelastic scattering (SIDIS) measurements for the unidentified light charged hadron productions. The SIDIS data which has been measured by the COMPASS experiment could allow the flavor dependence of the FFs to be well constrained. We exploit the analytic derivative of the Neural Network (NN) for fitting of FFs at next-to-leading-order (NLO) accuracy in the perturbative QCD (pQCD). The Monte Carlo method is implied for all sources of experimental uncertainties and the Parton distribution functions (PDFs) as well. Very good agreements are achieved between the SHK22.h FFs set and the most recent QCD fits available in literature, namely JAM20 and NNFF1.1h. In addition, we discuss the impact arising from the inclusion of SIDIS data on the extracted light-charged hadron FFs. The global QCD resulting at NLO for charged hadron FFs provides valuable insights for applications in present and future high-energy measurement of charged hadron final state processes. |
1012.0507 | Federico Alberto Ceccopieri | Federico Alberto Ceccopieri | Associated production of one particle and a Drell-Yan pair in hadronic
collisions | 15 pages, 4 figures | Phys.Lett.B703:491-497,2011 | 10.1016/j.physletb.2011.08.038 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a collinear factorization formula for the associated production of
one particle and a Drell-Yan pair in hadronic collisions. It is shown that
additional collinear singularities appearing in the next-to-leading order
calculations that can not be factorized into parton and fragmentation functions
are systematically renormalized by introducing fracture functions.
Next-to-leading order coefficient functions for cross-sections double
differential in the fractional energy of the identified hadron and lepton pair
invariant mass are presented.
| [
{
"created": "Thu, 2 Dec 2010 17:17:53 GMT",
"version": "v1"
}
] | 2015-03-17 | [
[
"Ceccopieri",
"Federico Alberto",
""
]
] | We propose a collinear factorization formula for the associated production of one particle and a Drell-Yan pair in hadronic collisions. It is shown that additional collinear singularities appearing in the next-to-leading order calculations that can not be factorized into parton and fragmentation functions are systematically renormalized by introducing fracture functions. Next-to-leading order coefficient functions for cross-sections double differential in the fractional energy of the identified hadron and lepton pair invariant mass are presented. |
1807.05094 | T. Lappi | B. Duclou\'e, T. Lappi and H. M\"antysaari | Forward rapidity isolated photon production in proton-nucleus collisions | 4 pages, 4 figures, talk by T.L. at the Quark Matter 2018 conference | null | 10.1016/j.nuclphysa.2018.10.064 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate isolated photon production at forward rapidities in
proton-nucleus collisions in the Color Glass Condensate framework. Our
calculation uses dipole cross sections solved from the running coupling
Balitsky-Kovchegov equation with an initial condition fit to deep inelastic
scattering data and extended to nuclei with an optical Glauber procedure that
introduces no additional parameters beyond the basic nuclear geometry. We
present predictions for future forward RHIC and LHC measurements. The
predictions are also compared to updated results for the nuclear modification
factors for pion production, Drell-Yan dileptons and $J/\psi$ mesons in the
same forward kinematics, consistently calculated in the same theoretical
framework. We find that leading order, running coupling high energy evolution
in the CGC picture leads to a significant nuclear suppression at forward
rapidities. This nuclear suppression is stronger for photons than for pions. We
also discuss how this might change with next-to-leading order high energy
evolution.
| [
{
"created": "Fri, 13 Jul 2018 14:08:17 GMT",
"version": "v1"
}
] | 2019-02-20 | [
[
"Ducloué",
"B.",
""
],
[
"Lappi",
"T.",
""
],
[
"Mäntysaari",
"H.",
""
]
] | We calculate isolated photon production at forward rapidities in proton-nucleus collisions in the Color Glass Condensate framework. Our calculation uses dipole cross sections solved from the running coupling Balitsky-Kovchegov equation with an initial condition fit to deep inelastic scattering data and extended to nuclei with an optical Glauber procedure that introduces no additional parameters beyond the basic nuclear geometry. We present predictions for future forward RHIC and LHC measurements. The predictions are also compared to updated results for the nuclear modification factors for pion production, Drell-Yan dileptons and $J/\psi$ mesons in the same forward kinematics, consistently calculated in the same theoretical framework. We find that leading order, running coupling high energy evolution in the CGC picture leads to a significant nuclear suppression at forward rapidities. This nuclear suppression is stronger for photons than for pions. We also discuss how this might change with next-to-leading order high energy evolution. |
hep-ph/9411275 | Benjamin Grinstein | Benjamin Grinstein | An Introduction To The Theory Of Heavy Mesons And Baryons | Re-posted: there are requests, and previous version not processing
under modern TeX. Figures included. 70 pages, harvmac, 15 figures | null | null | UCSD/PTH 94-24 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Introductory lectures (delivered at TASI, June 1994) on heavy quarks and
heavy quark effective field theory. Applications to inclusive semileptonic
decays and to interactions with light mesons are covered in detail.
| [
{
"created": "Fri, 11 Nov 1994 21:43:30 GMT",
"version": "v1"
},
{
"created": "Wed, 14 Dec 2016 06:17:43 GMT",
"version": "v2"
}
] | 2016-12-15 | [
[
"Grinstein",
"Benjamin",
""
]
] | Introductory lectures (delivered at TASI, June 1994) on heavy quarks and heavy quark effective field theory. Applications to inclusive semileptonic decays and to interactions with light mesons are covered in detail. |
2306.17673 | V\'ictor Montesinos | Victor Montesinos, Miguel Albaladejo, Juan Nieves, Laura Tolos | Properties of the $T_{cc}(3875)^+$ and $T_{\bar c\bar c}(3875)^-$ (and
their heavy-quark spin partners) in nuclear matter | 17 pages, 9 figures | null | null | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | We discuss the modification of the properties of the tetraquark-like
$T_{cc}(3875)^+$ and $T_{\bar c\bar c}(3875)^-$ states in dense nuclear matter.
We consider the $T_{cc}^+$ and $T_{\bar c\bar c}^-$ in vacuum as purely
isoscalar $D^{\ast} D$ and $\overline{D}{}^{\ast} \overline{D}$ $S$-wave bound
states, respectively, dynamically generated from a heavy-quark effective
interaction between the charmed mesons. We compute the $D$, $\overline{D}$,
$D^*$, and $\overline{D}{}^{*}$ spectral functions embedded in a nuclear medium
and use them to determine the corresponding $T_{cc}^+$ and $T_{\bar c\bar c}^-$
self energies and spectral functions. We find important modifications of the
$D^{\ast} D$ and $\overline{D}{}^{\ast} \overline{D}$ scattering amplitudes and
of the pole position of these exotic states already for $\rho_0/2$, with
$\rho_0$ the normal nuclear density. We also discuss the dependence of these
results on the $D^{\ast} D$ ($\overline{D}{}^{\ast} \overline{D}$) molecular
component in the $T_{cc}^+$ ($T_{\bar c\bar c}^-$ ) wave-function. Owing to the
different nature of the $D^{(*)}N$ and $\overline{D}{}^{(*)}N$ interactions, we
find characteristic changes of the in-medium properties of the $T_{cc}(3875)^+$
and $T_{\bar c\bar c}(3875)^-$, which become increasingly visible as the
density increases. The experimental confirmation of the found distinctive
density-pattern will give support to the molecular picture of these
tetraquark-like states, since in the case they were colourless compact quark
structures the density behaviour of their respective nuclear medium spectral
functions would likely be similar. Finally, we perform similar analyses for the
isoscalar $J^P=1^+$ heavy-quark spin symmetry partners of the $T_{cc}^+$
($T_{cc}^{*+}$) and the $T_{\bar c\bar c}^-$ ($T_{\bar c\bar c}^{*-}$) by
considering the $D^{*0}D^{*+}$ and $\overline{D}{}^{*0} D^{*-}$ scattering
$T-$matrices.
| [
{
"created": "Fri, 30 Jun 2023 14:03:13 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Sep 2023 13:50:13 GMT",
"version": "v2"
}
] | 2023-09-07 | [
[
"Montesinos",
"Victor",
""
],
[
"Albaladejo",
"Miguel",
""
],
[
"Nieves",
"Juan",
""
],
[
"Tolos",
"Laura",
""
]
] | We discuss the modification of the properties of the tetraquark-like $T_{cc}(3875)^+$ and $T_{\bar c\bar c}(3875)^-$ states in dense nuclear matter. We consider the $T_{cc}^+$ and $T_{\bar c\bar c}^-$ in vacuum as purely isoscalar $D^{\ast} D$ and $\overline{D}{}^{\ast} \overline{D}$ $S$-wave bound states, respectively, dynamically generated from a heavy-quark effective interaction between the charmed mesons. We compute the $D$, $\overline{D}$, $D^*$, and $\overline{D}{}^{*}$ spectral functions embedded in a nuclear medium and use them to determine the corresponding $T_{cc}^+$ and $T_{\bar c\bar c}^-$ self energies and spectral functions. We find important modifications of the $D^{\ast} D$ and $\overline{D}{}^{\ast} \overline{D}$ scattering amplitudes and of the pole position of these exotic states already for $\rho_0/2$, with $\rho_0$ the normal nuclear density. We also discuss the dependence of these results on the $D^{\ast} D$ ($\overline{D}{}^{\ast} \overline{D}$) molecular component in the $T_{cc}^+$ ($T_{\bar c\bar c}^-$ ) wave-function. Owing to the different nature of the $D^{(*)}N$ and $\overline{D}{}^{(*)}N$ interactions, we find characteristic changes of the in-medium properties of the $T_{cc}(3875)^+$ and $T_{\bar c\bar c}(3875)^-$, which become increasingly visible as the density increases. The experimental confirmation of the found distinctive density-pattern will give support to the molecular picture of these tetraquark-like states, since in the case they were colourless compact quark structures the density behaviour of their respective nuclear medium spectral functions would likely be similar. Finally, we perform similar analyses for the isoscalar $J^P=1^+$ heavy-quark spin symmetry partners of the $T_{cc}^+$ ($T_{cc}^{*+}$) and the $T_{\bar c\bar c}^-$ ($T_{\bar c\bar c}^{*-}$) by considering the $D^{*0}D^{*+}$ and $\overline{D}{}^{*0} D^{*-}$ scattering $T-$matrices. |
2101.11248 | Li-Hua Song | Li-Hua Song, Peng-Qi Wang, Yin-Jie Zhang | The Drell-Yan nuclear modification due to the nuclear effects of nPDFs
and initial-state parton energy loss | It is to be published in Chinese Physics C | null | 10.1088/1674-1137/abe110 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | By globally analyzing nuclear Drell-Yan data including all incident energies,
the nuclear effects of nPDFs and initial-state parton energy loss are
investigated. Based on Landau-Pomeranchuk-Migdal (LPM) regime, the calculations
are carried out by means of the analytic parametrizations of quenching weights
derived from the Baier-Dokshitzer-Mueller-Peign$\acute{e}$-Schiff (BDMPS)
formalism and using the new EPPS16 nPDFs. It is found that the results are in
good agreement with the data and the role of the energy loss effect on the
suppression of Drell-Yan ratios is prominent, especially for low-mass Drell-Yan
measurements. The nuclear effects of nPDFs becomes more obvious with the
nuclear mass number A, the same as the energy loss effect. By global fit, the
transport coefficient extracted is $\hat{q}=0.26\pm0.04$ GeV$^{2}$/fm. In
addition, to avoid diminishing the QCD NLO correction on the data form of
Drell-Yan ratios, the separate calculations about the Compton differential
cross section ratios $R_{Fe(W)/C}(x_{F})$ at 120GeV are performed, which
provides a feasible way to better distinguish the gluon energy loss in Compton
scattering. It is found that the role of the initial-state gluon energy loss on
the suppression of Compton scattering rations is not very important and becomes
disappear with the increase of $x_{F}$.
| [
{
"created": "Wed, 27 Jan 2021 08:11:07 GMT",
"version": "v1"
}
] | 2021-05-26 | [
[
"Song",
"Li-Hua",
""
],
[
"Wang",
"Peng-Qi",
""
],
[
"Zhang",
"Yin-Jie",
""
]
] | By globally analyzing nuclear Drell-Yan data including all incident energies, the nuclear effects of nPDFs and initial-state parton energy loss are investigated. Based on Landau-Pomeranchuk-Migdal (LPM) regime, the calculations are carried out by means of the analytic parametrizations of quenching weights derived from the Baier-Dokshitzer-Mueller-Peign$\acute{e}$-Schiff (BDMPS) formalism and using the new EPPS16 nPDFs. It is found that the results are in good agreement with the data and the role of the energy loss effect on the suppression of Drell-Yan ratios is prominent, especially for low-mass Drell-Yan measurements. The nuclear effects of nPDFs becomes more obvious with the nuclear mass number A, the same as the energy loss effect. By global fit, the transport coefficient extracted is $\hat{q}=0.26\pm0.04$ GeV$^{2}$/fm. In addition, to avoid diminishing the QCD NLO correction on the data form of Drell-Yan ratios, the separate calculations about the Compton differential cross section ratios $R_{Fe(W)/C}(x_{F})$ at 120GeV are performed, which provides a feasible way to better distinguish the gluon energy loss in Compton scattering. It is found that the role of the initial-state gluon energy loss on the suppression of Compton scattering rations is not very important and becomes disappear with the increase of $x_{F}$. |
0911.2030 | Manimala Mitra | Sandhya Choubey, Manimala Mitra | Spontaneous R-parity violating type III seesaw | 26 pages | JHEP 1005:021,2010 | 10.1007/JHEP05(2010)021 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a model where neutrino masses are generated by a combination of
spontaneous R-parity violation and Type III seesaw. In addition to the usual
MSSM particle content, our model consists of one extra triplet matter chiral
superfield containing heavy SU(2) triplet fermions and its superpartners.
R-parity is broken spontaneously when the sneutrinos associated with the one
heavy neutrino as well as the three light neutrinos get vacuum expectation
values, giving rise to the mixed $8\times 8$ neutralino-neutrino mass matrix.
We show that our model can comfortably explain all the existing neutrino
oscillation data. Due to the presence of the triplet fermion, we have a pair of
additional heavy charged leptons which mix with the standard model charged
leptons and the charginos. This gives rise to a $6\times 6$ chargino-charged
lepton mass matrix, with 6 massive eigenstates. Finally we discuss about the
different R-parity violating possible decay modes and the distinctive collider
signatures which our model offers.
| [
{
"created": "Wed, 11 Nov 2009 18:53:44 GMT",
"version": "v1"
},
{
"created": "Thu, 13 May 2010 10:19:43 GMT",
"version": "v2"
}
] | 2010-05-28 | [
[
"Choubey",
"Sandhya",
""
],
[
"Mitra",
"Manimala",
""
]
] | We present a model where neutrino masses are generated by a combination of spontaneous R-parity violation and Type III seesaw. In addition to the usual MSSM particle content, our model consists of one extra triplet matter chiral superfield containing heavy SU(2) triplet fermions and its superpartners. R-parity is broken spontaneously when the sneutrinos associated with the one heavy neutrino as well as the three light neutrinos get vacuum expectation values, giving rise to the mixed $8\times 8$ neutralino-neutrino mass matrix. We show that our model can comfortably explain all the existing neutrino oscillation data. Due to the presence of the triplet fermion, we have a pair of additional heavy charged leptons which mix with the standard model charged leptons and the charginos. This gives rise to a $6\times 6$ chargino-charged lepton mass matrix, with 6 massive eigenstates. Finally we discuss about the different R-parity violating possible decay modes and the distinctive collider signatures which our model offers. |
hep-ph/0201090 | Sergio Palomares-Ruiz | J. Bernabeu and S. Palomares-Ruiz | The sign of dm2_{31} and the muon-charge asymmetry for atmospheric
neutrinos | 6 pp, 1 fig. Talk given at the 7th International Workshop on Topics
in Astroparticles and Underground Physics (TAUP2001), Laboratori Nazionali
del Gran Sasso, Italy, September 8-12, 2001 | Nucl.Phys.Proc.Suppl. 110 (2002) 339-341 | 10.1016/S0920-5632(02)01503-7 | null | hep-ph | null | We discuss the possibility to measure the sign of dm2_{31} from
matter-induced charge asymmetries in atmospheric neutrino oscillations. The
main conclusion is that an impact on the nu_mu survival probability requires
the action of the MSW resonance, which becomes visible for baselines above
\~7000 km.
| [
{
"created": "Fri, 11 Jan 2002 15:41:11 GMT",
"version": "v1"
}
] | 2015-07-27 | [
[
"Bernabeu",
"J.",
""
],
[
"Palomares-Ruiz",
"S.",
""
]
] | We discuss the possibility to measure the sign of dm2_{31} from matter-induced charge asymmetries in atmospheric neutrino oscillations. The main conclusion is that an impact on the nu_mu survival probability requires the action of the MSW resonance, which becomes visible for baselines above \~7000 km. |
1411.4675 | German Rodrigo | Johann H. Kuehn and German Rodrigo | Forward-backward and charge asymmetries at Tevatron and the LHC | 8 pages, 3 figures. Presented at 8th International Workshop on the
CKM Unitarity Triangle (CKM 2014), Vienna, Austria, September 8-12, 2014 | null | null | LPN14-125, LPN14-032, IFIC/14-75 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We provide a qualitative and quantitative unified picture of the charge
asymmetry in top quark pair production at hadron colliders in the SM and
summarise the most recent experimental measurements.
| [
{
"created": "Mon, 17 Nov 2014 21:30:27 GMT",
"version": "v1"
}
] | 2014-11-19 | [
[
"Kuehn",
"Johann H.",
""
],
[
"Rodrigo",
"German",
""
]
] | We provide a qualitative and quantitative unified picture of the charge asymmetry in top quark pair production at hadron colliders in the SM and summarise the most recent experimental measurements. |
hep-ph/9712410 | masanori Miyama | M. Hirai, S. Kumano and M. Miyama (Saga University) | Numerical solution of Q^2 evolution equation for the transversity
distribution Delta_T q | 1+29 pages, LaTeX2e, epsfig.sty, amsmath.sty, 6 eps figures.
Submitted for publication. Complete postscript file is available at
ftp://ftp.cc.saga-u.ac.jp/pub/paper/riko/quantum1 or at
http://www.cc.saga-u.ac.jp/saga-u/riko/physics/quantum1/structure.html Our
evolution program may be obtained upon email request. (See the WWW home page
for the details.) Email: 96sm18@edu.cc.saga-u.ac.jp, kumanos@cc.saga-u.ac.jp,
96td25@edu.cc.saga-u.ac.jp | Comput.Phys.Commun.111:150-166,1998 | 10.1016/S0010-4655(98)00028-9 | SAGA-HE-125-97 | hep-ph hep-ex nucl-th | null | We investigate numerical solution of the Dokshitzer-Gribov-Lipatov-Altarelli-
Parisi (DGLAP) Q^2 evolution equation for the transversity distribution Delta_T
q or the structure function h_1. The leading-order (LO) and next-to-
leading-order (NLO) evolution equations are studied. The renormalization scheme
is MS or overline{MS} in the NLO case. Dividing the variables x and Q^2 into
small steps, we solve the integrodifferential equations by the Euler method in
the variable Q^2 and by the Simpson method in the variable x. Numerical results
indicate that accuracy is better than 1% in the region 10^{-5}<x<0.8 if more
than fifty Q^2 steps and more than five hundred x steps are taken. We provide a
FORTRAN program for the Q^2 evolution and devolution of the transversity
distribution Delta_T q or h_1. Using the program, we show the LO and NLO
evolution results of the valence-quark distribution Delta_T u_v + Delta_T d_v,
the singlet distribution sum_i (Delta_T q_i + Delta_T qbar_i), and the flavor
asymmetric distribution Delta_T ubar - Delta_T dbar.They are also compared with
the longitudinal evolution results.
| [
{
"created": "Wed, 17 Dec 1997 09:16:08 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Hirai",
"M.",
"",
"Saga University"
],
[
"Kumano",
"S.",
"",
"Saga University"
],
[
"Miyama",
"M.",
"",
"Saga University"
]
] | We investigate numerical solution of the Dokshitzer-Gribov-Lipatov-Altarelli- Parisi (DGLAP) Q^2 evolution equation for the transversity distribution Delta_T q or the structure function h_1. The leading-order (LO) and next-to- leading-order (NLO) evolution equations are studied. The renormalization scheme is MS or overline{MS} in the NLO case. Dividing the variables x and Q^2 into small steps, we solve the integrodifferential equations by the Euler method in the variable Q^2 and by the Simpson method in the variable x. Numerical results indicate that accuracy is better than 1% in the region 10^{-5}<x<0.8 if more than fifty Q^2 steps and more than five hundred x steps are taken. We provide a FORTRAN program for the Q^2 evolution and devolution of the transversity distribution Delta_T q or h_1. Using the program, we show the LO and NLO evolution results of the valence-quark distribution Delta_T u_v + Delta_T d_v, the singlet distribution sum_i (Delta_T q_i + Delta_T qbar_i), and the flavor asymmetric distribution Delta_T ubar - Delta_T dbar.They are also compared with the longitudinal evolution results. |
2203.10121 | Bingrong Yu | Bingrong Yu, Shun Zhou | CP violation and flavor invariants in the seesaw effective field theory | 44 pages, 4 tables, more discussions and references added, version
accepted by JHEP | JHEP 08 (2022) 017 | 10.1007/JHEP08(2022)017 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we systematically study the algebraic structure of the ring of
the flavor invariants and the sources of CP violation in the seesaw effective
field theory (SEFT), which is obtained by integrating out heavy Majorana
neutrinos in the type-I seesaw model at the tree level and thus includes the
dimension-five Weinberg operator and one dimension-six operator. For the first
time, we calculate the Hilbert series and explicitly construct all the primary
flavor invariants in the SEFT. We show that all the physical parameters can be
extracted using the primary invariants and any CP-violating observable can be
expressed as the linear combination of CP-odd flavor invariants. The
calculation of the Hilbert series shows that there is an equal number of
primary flavor invariants in the SEFT and in the full seesaw model, which
reveals the intimate connection between the flavor space of the SEFT and that
of its ultraviolet theory. A proper matching procedure of the flavor invariants
is accomplished between the SEFT and the full seesaw model, through which one
can establish a direct link between the CP asymmetries in leptogenesis and
those in low-energy neutrino oscillations.
| [
{
"created": "Fri, 18 Mar 2022 18:41:53 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Jun 2022 10:15:19 GMT",
"version": "v2"
}
] | 2022-08-03 | [
[
"Yu",
"Bingrong",
""
],
[
"Zhou",
"Shun",
""
]
] | In this paper, we systematically study the algebraic structure of the ring of the flavor invariants and the sources of CP violation in the seesaw effective field theory (SEFT), which is obtained by integrating out heavy Majorana neutrinos in the type-I seesaw model at the tree level and thus includes the dimension-five Weinberg operator and one dimension-six operator. For the first time, we calculate the Hilbert series and explicitly construct all the primary flavor invariants in the SEFT. We show that all the physical parameters can be extracted using the primary invariants and any CP-violating observable can be expressed as the linear combination of CP-odd flavor invariants. The calculation of the Hilbert series shows that there is an equal number of primary flavor invariants in the SEFT and in the full seesaw model, which reveals the intimate connection between the flavor space of the SEFT and that of its ultraviolet theory. A proper matching procedure of the flavor invariants is accomplished between the SEFT and the full seesaw model, through which one can establish a direct link between the CP asymmetries in leptogenesis and those in low-energy neutrino oscillations. |
1811.04435 | Kun Wang | Kun Wang, Fei Wang, Jingya Zhu, Quanlin Jie | The semi-constrained NMSSM in light of muon g-2, LHC, and dark matter
constraints | references added including CMS report 1811.08459 | Chinese Physics C, 2018, 42(10): 103109-103109 | 10.1088/1674-1137/42/10/103109 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The semi-constrained NMSSM (scNMSSM) extends the MSSM by a singlet field, and
requires unification of the soft SUSY breaking terms in the squark and slepton
sectors, while it allows that in the Higgs sector to be different. We try to
interpret the muon g-2 in the scNMSSM, under the constraints of 125 GeV Higgs
data, B physics, searches for low and high mass resonances, searches for SUSY
particles at the LHC, dark matter relic density by WMAP/Planck, and direct
searches for dark matter by LUX, XENON1T, and PandaX-II. We find that under the
above constraints, the scNMSSM can still (i) satisfy muon g-2 at 1$\sigma$
level, with a light muon sneutrino and light chargino; (ii) predict a
highly-singlet-dominated 95~GeV Higgs, with a diphoton rate as hinted at by CMS
data, because of a light higgsino-like chargino and moderate $\lambda$; (iii)
get low fine tuning from the GUT scale with small $\mu_{\rm eff},\, M_0,\,
M_{1/2},\, {\rm and}\, A_0$, with a lighter stop mass which can be as low as
about 500 GeV, which can be further checked in future studies with search
results from the 13~TeV LHC; (iv) have the lightest neutralino be
singlino-dominated or higgsino-dominated, while the bino and wino are heavier
because of high gluino bounds at the LHC and universal gaugino conditions at
the GUT scale; (v) satisfy all the above constraints, although it is not easy
for the lightest neutralino, as the only dark matter candidate, to get enough
relic density. Several ways to increase relic density are discussed.
| [
{
"created": "Sun, 11 Nov 2018 16:39:35 GMT",
"version": "v1"
},
{
"created": "Sun, 25 Nov 2018 02:49:05 GMT",
"version": "v2"
}
] | 2018-11-27 | [
[
"Wang",
"Kun",
""
],
[
"Wang",
"Fei",
""
],
[
"Zhu",
"Jingya",
""
],
[
"Jie",
"Quanlin",
""
]
] | The semi-constrained NMSSM (scNMSSM) extends the MSSM by a singlet field, and requires unification of the soft SUSY breaking terms in the squark and slepton sectors, while it allows that in the Higgs sector to be different. We try to interpret the muon g-2 in the scNMSSM, under the constraints of 125 GeV Higgs data, B physics, searches for low and high mass resonances, searches for SUSY particles at the LHC, dark matter relic density by WMAP/Planck, and direct searches for dark matter by LUX, XENON1T, and PandaX-II. We find that under the above constraints, the scNMSSM can still (i) satisfy muon g-2 at 1$\sigma$ level, with a light muon sneutrino and light chargino; (ii) predict a highly-singlet-dominated 95~GeV Higgs, with a diphoton rate as hinted at by CMS data, because of a light higgsino-like chargino and moderate $\lambda$; (iii) get low fine tuning from the GUT scale with small $\mu_{\rm eff},\, M_0,\, M_{1/2},\, {\rm and}\, A_0$, with a lighter stop mass which can be as low as about 500 GeV, which can be further checked in future studies with search results from the 13~TeV LHC; (iv) have the lightest neutralino be singlino-dominated or higgsino-dominated, while the bino and wino are heavier because of high gluino bounds at the LHC and universal gaugino conditions at the GUT scale; (v) satisfy all the above constraints, although it is not easy for the lightest neutralino, as the only dark matter candidate, to get enough relic density. Several ways to increase relic density are discussed. |
1804.09720 | Anders Johan Andreassen | Anders Andreassen, Ilya Feige, Christopher Frye, Matthew D. Schwartz | JUNIPR: a Framework for Unsupervised Machine Learning in Particle
Physics | 37 pages, 24 figures | null | 10.1140/epjc/s10052-019-6607-9 | null | hep-ph stat.ML | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In applications of machine learning to particle physics, a persistent
challenge is how to go beyond discrimination to learn about the underlying
physics. To this end, a powerful tool would be a framework for unsupervised
learning, where the machine learns the intricate high-dimensional contours of
the data upon which it is trained, without reference to pre-established labels.
In order to approach such a complex task, an unsupervised network must be
structured intelligently, based on a qualitative understanding of the data. In
this paper, we scaffold the neural network's architecture around a
leading-order model of the physics underlying the data. In addition to making
unsupervised learning tractable, this design actually alleviates existing
tensions between performance and interpretability. We call the framework
JUNIPR: "Jets from UNsupervised Interpretable PRobabilistic models". In this
approach, the set of particle momenta composing a jet are clustered into a
binary tree that the neural network examines sequentially. Training is
unsupervised and unrestricted: the network could decide that the data bears
little correspondence to the chosen tree structure. However, when there is a
correspondence, the network's output along the tree has a direct physical
interpretation. JUNIPR models can perform discrimination tasks, through the
statistically optimal likelihood-ratio test, and they permit visualizations of
discrimination power at each branching in a jet's tree. Additionally, JUNIPR
models provide a probability distribution from which events can be drawn,
providing a data-driven Monte Carlo generator. As a third application, JUNIPR
models can reweight events from one (e.g. simulated) data set to agree with
distributions from another (e.g. experimental) data set.
| [
{
"created": "Wed, 25 Apr 2018 18:00:01 GMT",
"version": "v1"
}
] | 2019-02-20 | [
[
"Andreassen",
"Anders",
""
],
[
"Feige",
"Ilya",
""
],
[
"Frye",
"Christopher",
""
],
[
"Schwartz",
"Matthew D.",
""
]
] | In applications of machine learning to particle physics, a persistent challenge is how to go beyond discrimination to learn about the underlying physics. To this end, a powerful tool would be a framework for unsupervised learning, where the machine learns the intricate high-dimensional contours of the data upon which it is trained, without reference to pre-established labels. In order to approach such a complex task, an unsupervised network must be structured intelligently, based on a qualitative understanding of the data. In this paper, we scaffold the neural network's architecture around a leading-order model of the physics underlying the data. In addition to making unsupervised learning tractable, this design actually alleviates existing tensions between performance and interpretability. We call the framework JUNIPR: "Jets from UNsupervised Interpretable PRobabilistic models". In this approach, the set of particle momenta composing a jet are clustered into a binary tree that the neural network examines sequentially. Training is unsupervised and unrestricted: the network could decide that the data bears little correspondence to the chosen tree structure. However, when there is a correspondence, the network's output along the tree has a direct physical interpretation. JUNIPR models can perform discrimination tasks, through the statistically optimal likelihood-ratio test, and they permit visualizations of discrimination power at each branching in a jet's tree. Additionally, JUNIPR models provide a probability distribution from which events can be drawn, providing a data-driven Monte Carlo generator. As a third application, JUNIPR models can reweight events from one (e.g. simulated) data set to agree with distributions from another (e.g. experimental) data set. |
2303.13128 | Piotr Kotko | Piotr Kotko, Leszek Motyka, Anna Stasto | Color Reconnection Effects in $J/\psi$ Hadroproduction | 12 pages, 3 figures, references added, typos corrected | null | 10.1016/j.physletb.2023.138104 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate production of $J/\psi$ mesons in hadron-hadron collisions,
defined as low invariant mass $c\bar{c}$ singlets produced in a mixture of
perturbative and nonperturbative mechanisms provided by the PYTHIA Monte Carlo.
We find that in this model the color reconnection mechanism, which breaks the
factorization, is essential to reasonably describe the experimental data.
| [
{
"created": "Thu, 23 Mar 2023 09:30:56 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Aug 2023 08:31:37 GMT",
"version": "v2"
}
] | 2023-08-16 | [
[
"Kotko",
"Piotr",
""
],
[
"Motyka",
"Leszek",
""
],
[
"Stasto",
"Anna",
""
]
] | We investigate production of $J/\psi$ mesons in hadron-hadron collisions, defined as low invariant mass $c\bar{c}$ singlets produced in a mixture of perturbative and nonperturbative mechanisms provided by the PYTHIA Monte Carlo. We find that in this model the color reconnection mechanism, which breaks the factorization, is essential to reasonably describe the experimental data. |
1310.5209 | Majid Hashemi | Majid Hashemi | Observability of Heavy Charged Higgs through s-channel Single Top Events
at LHC | 18 pages, 16 figures | JHEP11(2013)005 | 10.1007/JHEP11(2013)005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The charged Higgs bosons can be produced as a resonance in s-channel single
top events. The light charged Higgs in such events preferably decays to a pair
of $\tau \nu$ thus making it difficult to distinguish from the large single W
events producing the same final state. However, the heavy charged Higgs decay
to a pair of $t \bar{b}$ can be extracted from the SM background events. The
final state under consideration in this paper contains the top quark decay to
$W^+ b$ followed by $W^+$ decay to electrons or muons. It is shown that this
signal can be observed at LHC at a large area of MSSM phase space ($m(H^+),
tan\beta$). Finally $5\sigma$ and 95% CL exclusion contours are presented at
different integrated luminosities of LHC assuming a nominal center of mass
energy of $\sqrt{s}$ = 14 TeV.
| [
{
"created": "Sat, 19 Oct 2013 08:31:24 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Oct 2013 11:19:31 GMT",
"version": "v2"
}
] | 2013-11-28 | [
[
"Hashemi",
"Majid",
""
]
] | The charged Higgs bosons can be produced as a resonance in s-channel single top events. The light charged Higgs in such events preferably decays to a pair of $\tau \nu$ thus making it difficult to distinguish from the large single W events producing the same final state. However, the heavy charged Higgs decay to a pair of $t \bar{b}$ can be extracted from the SM background events. The final state under consideration in this paper contains the top quark decay to $W^+ b$ followed by $W^+$ decay to electrons or muons. It is shown that this signal can be observed at LHC at a large area of MSSM phase space ($m(H^+), tan\beta$). Finally $5\sigma$ and 95% CL exclusion contours are presented at different integrated luminosities of LHC assuming a nominal center of mass energy of $\sqrt{s}$ = 14 TeV. |
hep-ph/0507299 | Brigitte Hiller | Brigitte Hiller, Alexander A. Osipov, Alex H. Blin | Perturbative approach to U_A(1) breaking | LaTeX, 9 pages, Prepared for the Proceedings of The International
Conference on High Energy and Mathematical Physics, Marrakech, Morocco, 4-7
April 2005 | Afr.J.Math.Phys.3:65-72,2006 | null | null | hep-ph | null | The six-quark instanton induced 't Hooft interaction is considered in
combination with the Nambu-Jona-Lasinio (NJL) type U_L(3)X U_R(3) chiral
symmetric Lagrangian. We discuss the bosonization of this multi-quark
interaction, taking the U_A(1) breaking as a perturbation. We discuss its
relation with the usual approach.
| [
{
"created": "Tue, 26 Jul 2005 11:24:50 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Hiller",
"Brigitte",
""
],
[
"Osipov",
"Alexander A.",
""
],
[
"Blin",
"Alex H.",
""
]
] | The six-quark instanton induced 't Hooft interaction is considered in combination with the Nambu-Jona-Lasinio (NJL) type U_L(3)X U_R(3) chiral symmetric Lagrangian. We discuss the bosonization of this multi-quark interaction, taking the U_A(1) breaking as a perturbation. We discuss its relation with the usual approach. |
hep-ph/9506207 | Nicola Di Bartolomeo | P. Colangelo, F. De Fazio, N. Di Bartolomeo, R. Gatto and G. Nardulli | Strong coupling of excited heavy mesons | 31 pages, RevTeX, 4 figures appended as uuencoded file | Phys.Rev. D52 (1995) 6422-6434 | 10.1103/PhysRevD.52.6422 | UGVA-DPT 1995/05-890; BARI-TH/95-200 | hep-ph | null | We compute the strong coupling constant $G_{B^{**} B \pi} \; (G_{D^{**} D
\pi})$, where $B^{**}$ ($D^{**}$) is the $0^+$ $P-$wave $b \bar q \; (c \bar
q)$ state, by QCD sum rules and by light-cone sum rules. The two methods give
compatible results in the limit $m_Q \to \infty$, with a rather large value of
the coupling constant. We apply the results to the calculation of the hadronic
widths of the positive parity $B$ and $D$ states and to the chiral loop
contribution to the ratio $f_{D_s}/f_D$.
| [
{
"created": "Thu, 1 Jun 1995 17:25:30 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Colangelo",
"P.",
""
],
[
"De Fazio",
"F.",
""
],
[
"Di Bartolomeo",
"N.",
""
],
[
"Gatto",
"R.",
""
],
[
"Nardulli",
"G.",
""
]
] | We compute the strong coupling constant $G_{B^{**} B \pi} \; (G_{D^{**} D \pi})$, where $B^{**}$ ($D^{**}$) is the $0^+$ $P-$wave $b \bar q \; (c \bar q)$ state, by QCD sum rules and by light-cone sum rules. The two methods give compatible results in the limit $m_Q \to \infty$, with a rather large value of the coupling constant. We apply the results to the calculation of the hadronic widths of the positive parity $B$ and $D$ states and to the chiral loop contribution to the ratio $f_{D_s}/f_D$. |
2105.01678 | Shaikh Saad | Ilja Dor\v{s}ner, Emina D\v{z}aferovi\'c-Ma\v{s}i\'c, Shaikh Saad | A Parameter Space Exploration of the Minimal SU(5) Unification | 20 pages + references, 3 figures; accepted in Physical Review D
(PRD); version to appear in PRD | Phys. Rev. D 104, 015023 (2021) | 10.1103/PhysRevD.104.015023 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We present phenomenological study of the most minimal realistic $SU(5)$ model
that owns its predictivity solely to the gauge symmetry and the
representational content. The model is built entirely out of the fields
residing in the first five lowest dimensional representations that transform
non-trivially under the $SU(5)$ gauge group. It has eighteen real parameters
and fourteen phases, all in all, to address experimental observables of the
Standard Model fermions and accomplishes that via simultaneous use of three
different mass generation mechanisms. Furthermore, it inextricably links the
origin of the neutrino mass to the experimentally observed difference between
the down-type quark and charged lepton masses. The main predictions of the
model are that $(i)$ the neutrinos are Majorana particles, $(ii)$ one neutrino
is massless, $(iii)$ the neutrinos have normal mass ordering, and $(iv)$ there
are four new scalar multiplets at or below a $120$ TeV mass scale. A one-loop
analysis demonstrates that an improvement of the current $p \rightarrow \pi^0
e^+$ partial lifetime limit by a factor of $2$, $15$, and $96$ would require
these four scalar multiplets to reside at or below the $100$ TeV, $10$ TeV, and
$1$ TeV mass scales, respectively.
| [
{
"created": "Tue, 4 May 2021 18:00:44 GMT",
"version": "v1"
},
{
"created": "Wed, 23 Jun 2021 06:02:40 GMT",
"version": "v2"
}
] | 2021-07-21 | [
[
"Doršner",
"Ilja",
""
],
[
"Džaferović-Mašić",
"Emina",
""
],
[
"Saad",
"Shaikh",
""
]
] | We present phenomenological study of the most minimal realistic $SU(5)$ model that owns its predictivity solely to the gauge symmetry and the representational content. The model is built entirely out of the fields residing in the first five lowest dimensional representations that transform non-trivially under the $SU(5)$ gauge group. It has eighteen real parameters and fourteen phases, all in all, to address experimental observables of the Standard Model fermions and accomplishes that via simultaneous use of three different mass generation mechanisms. Furthermore, it inextricably links the origin of the neutrino mass to the experimentally observed difference between the down-type quark and charged lepton masses. The main predictions of the model are that $(i)$ the neutrinos are Majorana particles, $(ii)$ one neutrino is massless, $(iii)$ the neutrinos have normal mass ordering, and $(iv)$ there are four new scalar multiplets at or below a $120$ TeV mass scale. A one-loop analysis demonstrates that an improvement of the current $p \rightarrow \pi^0 e^+$ partial lifetime limit by a factor of $2$, $15$, and $96$ would require these four scalar multiplets to reside at or below the $100$ TeV, $10$ TeV, and $1$ TeV mass scales, respectively. |
0708.1621 | Ikaros Bigi | I. I. Bigi, B. Blossier, A. Le Yaouanc, L. Oliver, O. P\`ene, J.-C.
Raynal, A. Oyanguren, P. Roudeau | Memorino on the `1/2 vs. 3/2 Puzzle' in $\bar B \to l \bar \nu X_c$ -- a
Year Later and a Bit Wiser | 21 pages, no figures; corrected address of one of the authors and
included new measurements by BaBar | Eur.Phys.J.C52:975-985,2007 | 10.1140/epjc/s10052-007-0425-1 | UND-HEP-07-BIG05, DESY 07-116, SFB/CPP-07-45, LPT-ORSAY 07-67, LAL
07-109 | hep-ph | null | The OPE treatment that has been so successful in describing inclusive $\bar B
\to l \bar \nu X_c$ decays yields sum rules (in particular the Uraltsev sum
rule and its higher moments) implying the dominance of the $P$ wave $j_q = 3/2$
charm states in $X_c$ over their $j_q=1/2$ counterparts. This prediction is
supported by other general arguments as well as quark model calculations, which
illustrate the OPE results, and by preliminary lattice findings. Its failure
would indicate a significant limitation in our theoretical understanding of
$\bar B \to l \bar \nu X_c$. Some experimental issues have been clarified since
a preliminary version of this note had appeared, yet the verdict on the
composition of the final states {\em beyond} $D$, $D^*$ and the two narrow $j_q
= 3/2$ resonances remains unsettled. Establishing which hadronic configurations
-- $D/D^* + \pi, D/D^* + 2 \pi, ...$ -- contribute, what their quantum numbers
are and their mass distributions will require considerable experimental effort.
We explain the theoretical issues involved and why a better understanding of
them will be of significant value. Having significant contributions from a mass
continuum distribution below 2.5 GeV raises serious theoretical questions for
which we have no good answer. Two lists are given, one with measurements that
need to be done and one with items of theoretical homework. Some of the latter
can be done by employing existing theoretical tools, whereas others need new
ideas.
| [
{
"created": "Sun, 12 Aug 2007 19:26:29 GMT",
"version": "v1"
},
{
"created": "Tue, 4 Sep 2007 00:31:01 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Bigi",
"I. I.",
""
],
[
"Blossier",
"B.",
""
],
[
"Yaouanc",
"A. Le",
""
],
[
"Oliver",
"L.",
""
],
[
"Pène",
"O.",
""
],
[
"Raynal",
"J. -C.",
""
],
[
"Oyanguren",
"A.",
""
],
[
"Roudeau",
"P.... | The OPE treatment that has been so successful in describing inclusive $\bar B \to l \bar \nu X_c$ decays yields sum rules (in particular the Uraltsev sum rule and its higher moments) implying the dominance of the $P$ wave $j_q = 3/2$ charm states in $X_c$ over their $j_q=1/2$ counterparts. This prediction is supported by other general arguments as well as quark model calculations, which illustrate the OPE results, and by preliminary lattice findings. Its failure would indicate a significant limitation in our theoretical understanding of $\bar B \to l \bar \nu X_c$. Some experimental issues have been clarified since a preliminary version of this note had appeared, yet the verdict on the composition of the final states {\em beyond} $D$, $D^*$ and the two narrow $j_q = 3/2$ resonances remains unsettled. Establishing which hadronic configurations -- $D/D^* + \pi, D/D^* + 2 \pi, ...$ -- contribute, what their quantum numbers are and their mass distributions will require considerable experimental effort. We explain the theoretical issues involved and why a better understanding of them will be of significant value. Having significant contributions from a mass continuum distribution below 2.5 GeV raises serious theoretical questions for which we have no good answer. Two lists are given, one with measurements that need to be done and one with items of theoretical homework. Some of the latter can be done by employing existing theoretical tools, whereas others need new ideas. |
2010.03621 | Agustin Sabio Vera | Melina G\'omez Bock, Martin Hentschinski, and Agust\'in Sabio Vera | An effective field theory approach for electroweak interactions in the
high energy limit | 12 pages, 2 figures. Version to be published in European Physical
Journal C | null | 10.1140/epjc/s10052-020-08751-9 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an effective action for the electroweak sector of the Standard
Model valid for the calculation of scattering amplitudes in the high energy
(Regge) limit. Gauge invariant Wilson lines are introduced to describe
reggeized degrees of freedom whose interactions are generated by effective
emission vertices. From this approach previous results at leading logarithmic
accuracy for electroweak boson Regge trajectories are reproduced together with
the corresponding interaction kernels. The proposed framework lays the path for
calculations at higher orders in perturbation theory.
| [
{
"created": "Wed, 7 Oct 2020 19:43:21 GMT",
"version": "v1"
},
{
"created": "Fri, 11 Dec 2020 13:28:14 GMT",
"version": "v2"
}
] | 2021-02-03 | [
[
"Bock",
"Melina Gómez",
""
],
[
"Hentschinski",
"Martin",
""
],
[
"Vera",
"Agustín Sabio",
""
]
] | We present an effective action for the electroweak sector of the Standard Model valid for the calculation of scattering amplitudes in the high energy (Regge) limit. Gauge invariant Wilson lines are introduced to describe reggeized degrees of freedom whose interactions are generated by effective emission vertices. From this approach previous results at leading logarithmic accuracy for electroweak boson Regge trajectories are reproduced together with the corresponding interaction kernels. The proposed framework lays the path for calculations at higher orders in perturbation theory. |
1510.07616 | Giovanni Grilli di Cortona | Giovanni Grilli di Cortona | Searching SUSY from below | 8 pages, 4 figures, prepared for the Proceedings of the 18th
International Conference From the Planck Scale to the Electroweak Scale,
25-29 May 2015, Ioannina, Greece. Based on arXiv:1412.5952 | PoS(PLANCK 2015)054 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We studied the interplay between the mass reach for electroweakinos at future
hadron colliders and direct detection experiments. The lack of new phenomena at
the LCH motivates us to focus on split supersymmetry scenarios with different
electroweakino spectra. A 100 TeV hadron collider may reach masses up to 3 TeV
in models of anomaly mediation with long-lived thermal Winos. Moreover, in
scenarios where the lightest neutralino is not the only dark matter component,
the interplay between collider searches and direct detection experiments might
cover large part of the parameter space.
| [
{
"created": "Mon, 26 Oct 2015 19:58:09 GMT",
"version": "v1"
}
] | 2015-10-27 | [
[
"di Cortona",
"Giovanni Grilli",
""
]
] | We studied the interplay between the mass reach for electroweakinos at future hadron colliders and direct detection experiments. The lack of new phenomena at the LCH motivates us to focus on split supersymmetry scenarios with different electroweakino spectra. A 100 TeV hadron collider may reach masses up to 3 TeV in models of anomaly mediation with long-lived thermal Winos. Moreover, in scenarios where the lightest neutralino is not the only dark matter component, the interplay between collider searches and direct detection experiments might cover large part of the parameter space. |
hep-ph/0108213 | Peter Schweitzer | A.V. Efremov (Dubna, JINR), K. Goeke, P. Schweitzer (Ruhr U., Bochum) | Azimuthal asymmetry in electro-production of neutral pions in SIDIS | 12 pages, 10 figures. Fig.3c, Fig.4a updated, conclusions added | Phys.Lett.B522:37-48,2001; Erratum-ibid.B544:389-392,2002 | 10.1016/S0370-2693(01)01258-8 | RUB/TP2-08/01 | hep-ph | null | Recently HERMES has observed an azimuthal asymmetry in electro-production of
neutral pions in semi-inclusive deep-inelastic scattering of unpolarized
positrons off longitudinally polarized protons. This asymmetry (like those
observed in the production of charged pions) is well reproduced theoretically
by using the non-perturbative calculation of the proton transversity
distribution in the effective chiral quark-soliton model combined with
experimental DELPHI-data on the new T-odd Collins fragmentation function. There
are no free, adjustable parameters in the analysis. Using the $z$-dependence of
the HERMES azimuthal asymmetry and the calculated transversity distributions
the z-dependence of the Collins fragmentation function is obtained. The value
obtained from HERMES data is consistent with the DELPHI result, even though
these results refer to different scales.
| [
{
"created": "Sat, 25 Aug 2001 15:17:49 GMT",
"version": "v1"
},
{
"created": "Thu, 27 Sep 2001 10:59:51 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Efremov",
"A. V.",
"",
"Dubna, JINR"
],
[
"Goeke",
"K.",
"",
"Ruhr U., Bochum"
],
[
"Schweitzer",
"P.",
"",
"Ruhr U., Bochum"
]
] | Recently HERMES has observed an azimuthal asymmetry in electro-production of neutral pions in semi-inclusive deep-inelastic scattering of unpolarized positrons off longitudinally polarized protons. This asymmetry (like those observed in the production of charged pions) is well reproduced theoretically by using the non-perturbative calculation of the proton transversity distribution in the effective chiral quark-soliton model combined with experimental DELPHI-data on the new T-odd Collins fragmentation function. There are no free, adjustable parameters in the analysis. Using the $z$-dependence of the HERMES azimuthal asymmetry and the calculated transversity distributions the z-dependence of the Collins fragmentation function is obtained. The value obtained from HERMES data is consistent with the DELPHI result, even though these results refer to different scales. |
2111.04519 | Claudio Andrea Manzari | Claudio Andrea Manzari | Explaining the Cabibbo Angle Anomaly | 7 pages, 1 figure, contribution to The European Physical Society
Conference on High Energy Physics 2021 (EPS-HEP2021) | null | null | null | hep-ph hep-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | The Cabibbo-Cobayashi-Maskawa (CKM) matrix parametrizes the misalignement
between the up- and down-quark mass basis in the Standard Model (SM). The
observation of first row CKM unitarity violation has recently emerged as a new
anomaly of the SM, known as the "Cabibbo Angle Anomaly" (CAA). With current
measurements, comparing the elements $V_{ud}$ and $V_{us}$ extracted from beta
and kaon decays respectively, the tension with the SM prediction amounts to
$\sim$$3\,\sigma$. Recently, it has been pointed out that this anomaly can also
be seen as a discrepancy in the determination of the Fermi constant from muon
decay vs $\beta$ and K decays, once CKM unitarity is assumed. In fact, possible
explanations in terms on New Physics fall under two broad classes:
contributions to $\beta$ decay and/or to $\mu$ decay. In this proceedings, we
discuss these solutions in terms of gauge invariant dimension 6 operators in
SMEFT and simplified extensions of the Standard Model. The latter could
introduce correlations with other anomalies in the SM, pointing to new and
interesting directions for model building.
| [
{
"created": "Mon, 8 Nov 2021 14:08:10 GMT",
"version": "v1"
}
] | 2021-11-09 | [
[
"Manzari",
"Claudio Andrea",
""
]
] | The Cabibbo-Cobayashi-Maskawa (CKM) matrix parametrizes the misalignement between the up- and down-quark mass basis in the Standard Model (SM). The observation of first row CKM unitarity violation has recently emerged as a new anomaly of the SM, known as the "Cabibbo Angle Anomaly" (CAA). With current measurements, comparing the elements $V_{ud}$ and $V_{us}$ extracted from beta and kaon decays respectively, the tension with the SM prediction amounts to $\sim$$3\,\sigma$. Recently, it has been pointed out that this anomaly can also be seen as a discrepancy in the determination of the Fermi constant from muon decay vs $\beta$ and K decays, once CKM unitarity is assumed. In fact, possible explanations in terms on New Physics fall under two broad classes: contributions to $\beta$ decay and/or to $\mu$ decay. In this proceedings, we discuss these solutions in terms of gauge invariant dimension 6 operators in SMEFT and simplified extensions of the Standard Model. The latter could introduce correlations with other anomalies in the SM, pointing to new and interesting directions for model building. |
hep-ph/9805289 | James Wells | Stephen P. Martin and James D. Wells | Cornering gauge-mediated supersymmetry breaking with quasi-stable
sleptons at the Tevatron | 15 pages, latex, 5 figures | Phys. Rev. D 59, 035008 (1999) | 10.1103/PhysRevD.59.035008 | SLAC-PUB-7827 | hep-ph hep-ex | null | There are many theoretical reasons why heavy quasi-stable charged particles
might exist. Pair production of such particles at the Tevatron can produce
highly ionizing tracks (HITs) or fake muons. In gauge-mediated supersymmetry
breaking, sparticle production can lead to events with a pair of quasi-stable
sleptons, a significant fraction of which will have the same electric charge.
Depending on the production mechanism and the decay chain, they may also be
accompanied by additional energetic leptons. We study the relative importance
of the resulting signals for the Tevatron Run II. The relative fraction of
same-sign tracks to other background-free signals is an important diagnostic
tool in gauge-mediated supersymmetry breaking that may provide information
about mass splittings, tan(beta) and the number of messengers communicating
supersymmetry breaking.
| [
{
"created": "Mon, 11 May 1998 20:49:44 GMT",
"version": "v1"
}
] | 2016-08-25 | [
[
"Martin",
"Stephen P.",
""
],
[
"Wells",
"James D.",
""
]
] | There are many theoretical reasons why heavy quasi-stable charged particles might exist. Pair production of such particles at the Tevatron can produce highly ionizing tracks (HITs) or fake muons. In gauge-mediated supersymmetry breaking, sparticle production can lead to events with a pair of quasi-stable sleptons, a significant fraction of which will have the same electric charge. Depending on the production mechanism and the decay chain, they may also be accompanied by additional energetic leptons. We study the relative importance of the resulting signals for the Tevatron Run II. The relative fraction of same-sign tracks to other background-free signals is an important diagnostic tool in gauge-mediated supersymmetry breaking that may provide information about mass splittings, tan(beta) and the number of messengers communicating supersymmetry breaking. |
hep-ph/0207361 | Jan Govaerts | Jean El Bachir Mendy (University Cheikh Anta Diop, Dakar, Senegal) and
Jan Govaerts (UCL, Louvain-la-Neuve, Belgium) | A General Four-Fermion Effective Lagrangian for Dirac and Majorana
Neutrino-Charged Matter Interactions | To be published in the Proceedings of the Second International
Workshop on Contemporary Problems in Mathematical Physics, Cotonou, Republic
of Benin, 15 pages | null | null | null | hep-ph | null | Given the most general Lorentz invariant four-fermion effective interaction
possible for two neutrinos and two charged fermions, whether quarks or leptons,
all possible 2-to-2 processes involving two neutrinos, whether Dirac or
Majorana ones, and two charged fermions are considered. Explicit and convenient
expressions are given for the associated differential cross-sections. Such a
parametrization should help assess the sensitivity to physics beyond the
Standard Model of neutrino beam experiments which are in the design stage at
neutrino factories.
| [
{
"created": "Wed, 31 Jul 2002 08:39:22 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mendy",
"Jean El Bachir",
"",
"University Cheikh Anta Diop, Dakar, Senegal"
],
[
"Govaerts",
"Jan",
"",
"UCL, Louvain-la-Neuve, Belgium"
]
] | Given the most general Lorentz invariant four-fermion effective interaction possible for two neutrinos and two charged fermions, whether quarks or leptons, all possible 2-to-2 processes involving two neutrinos, whether Dirac or Majorana ones, and two charged fermions are considered. Explicit and convenient expressions are given for the associated differential cross-sections. Such a parametrization should help assess the sensitivity to physics beyond the Standard Model of neutrino beam experiments which are in the design stage at neutrino factories. |
hep-ph/9611300 | Alberto Polleri | A. Polleri, R.A. Broglia, P.M. Pizzochero and N.N. Scoccola | Rho meson properties in the Nambu-Jona-Lasinio model | 21 pages Latex, 4 figures, to be published in Z. Phys. A | Z.Phys. A357 (1997) 325-331 | 10.1007/s002180050249 | NTGMI-95-4 | hep-ph | null | Some properties of the rho vector meson are calculated within the
Nambu-Jona-Lasinio model, including processes that go beyond the random phase
approximation. To classify the higher order contributions, we adopt $1/N_c$ as
expansion parameter. In particular, we evaluate the leading order contributions
to the $\rho \rightarrow \pi \pi$ decay width, obtaining the value $\Gamma =
118$ MeV, and to the shift of the rho mass which turns out to be lowered by 64
MeV with respect to its RPA value. A set of model parameters is determined
accordingly.
| [
{
"created": "Mon, 11 Nov 1996 14:21:27 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Polleri",
"A.",
""
],
[
"Broglia",
"R. A.",
""
],
[
"Pizzochero",
"P. M.",
""
],
[
"Scoccola",
"N. N.",
""
]
] | Some properties of the rho vector meson are calculated within the Nambu-Jona-Lasinio model, including processes that go beyond the random phase approximation. To classify the higher order contributions, we adopt $1/N_c$ as expansion parameter. In particular, we evaluate the leading order contributions to the $\rho \rightarrow \pi \pi$ decay width, obtaining the value $\Gamma = 118$ MeV, and to the shift of the rho mass which turns out to be lowered by 64 MeV with respect to its RPA value. A set of model parameters is determined accordingly. |
1010.0496 | Robert Fleischer | Robert Fleischer | B Physics in the LHC Era: Selected Topics | 8 pages, 3 figures, invited talk at the 3rd Workshop on Theory,
Phenomenology and Experiments in Heavy Flavour Physics, Capri, Italy, 5-7
July 2010, to appear in the Proceedings | Nucl.Phys.Proc.Suppl.209:3-8,2010 | 10.1016/j.nuclphysbps.2010.12.002 | Nikhef-2010-034 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have just entered a new round in the testing of the flavour sector of the
Standard Model through high-precision measurements of B-meson decays. A
particularly exciting aspect is the exploration of the B_s-meson system at
LHCb. We focus on two particularly promising probes of new physics which may
give us first solid evidence for New Physics at the LHC: the strongly
suppressed rare decay B_s^0 -> mu^+mu^- and CP-violating effects in the B_s^0
-> J/psi phi channel. We discuss recent theoretical developments related to
these measurements and shall also sketch other highlights of the B-physics
programme in the LHC era.
| [
{
"created": "Mon, 4 Oct 2010 08:14:40 GMT",
"version": "v1"
}
] | 2015-03-17 | [
[
"Fleischer",
"Robert",
""
]
] | We have just entered a new round in the testing of the flavour sector of the Standard Model through high-precision measurements of B-meson decays. A particularly exciting aspect is the exploration of the B_s-meson system at LHCb. We focus on two particularly promising probes of new physics which may give us first solid evidence for New Physics at the LHC: the strongly suppressed rare decay B_s^0 -> mu^+mu^- and CP-violating effects in the B_s^0 -> J/psi phi channel. We discuss recent theoretical developments related to these measurements and shall also sketch other highlights of the B-physics programme in the LHC era. |
hep-ph/0112169 | Albert De Roeck | M. Battaglia, A. De Roeck, T. Rizzo | Graviton Production at CLIC | 5 pages, 5 figures, to appear on the Proceedings of the Snowmass 2001
Summer Study, Snowmass CO (USA), July 2001 | eConf C010630 (2001) E3022 | null | SLAC-PUB-9082 | hep-ph | null | Direct production of Kaluza-Klein states in the TeV range is studied for the
experimental environment at the multi-TeV $e^+e^-$ collider CLIC. The
sensitivity of such data to model parameters is discussed for the
Randall-Sundrum(RS) and TeV scale extra dimensional models.
| [
{
"created": "Wed, 12 Dec 2001 17:31:24 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Battaglia",
"M.",
""
],
[
"De Roeck",
"A.",
""
],
[
"Rizzo",
"T.",
""
]
] | Direct production of Kaluza-Klein states in the TeV range is studied for the experimental environment at the multi-TeV $e^+e^-$ collider CLIC. The sensitivity of such data to model parameters is discussed for the Randall-Sundrum(RS) and TeV scale extra dimensional models. |
hep-ph/9606423 | Edi Halyo | Edi Halyo (Stanford) | Hybrid Inflation from Supergravity D Terms | 9 pages in Latex. Two references added, version to appear in Phys.
Lett. B | Phys.Lett. B387 (1996) 43-47 | 10.1016/0370-2693(96)01001-5 | SU-ITP-96-28 | hep-ph | null | We argue that the mass of the inflaton can be much smaller than the Hubble
constant in supergravity models in which inflation is driven by D--terms and
not F--terms. We investigate a supergravity toy model which leads to hybrid
inflation due to an anomalous D--term. We show that the slow--roll condition
can be satisfied and the correct magnitude for density perturbations can be
obtained for some choice of model parameters. The kind of model considered can
naturally arise in some string derived supergravity models.
| [
{
"created": "Tue, 25 Jun 1996 04:41:43 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Aug 1996 22:37:51 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Halyo",
"Edi",
"",
"Stanford"
]
] | We argue that the mass of the inflaton can be much smaller than the Hubble constant in supergravity models in which inflation is driven by D--terms and not F--terms. We investigate a supergravity toy model which leads to hybrid inflation due to an anomalous D--term. We show that the slow--roll condition can be satisfied and the correct magnitude for density perturbations can be obtained for some choice of model parameters. The kind of model considered can naturally arise in some string derived supergravity models. |
1411.7321 | Christian Reuschle | Christian Reuschle | Event simulation for colliders - A basic overview | 13 pages. Plenary talk given at ACAT 2014 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this article we will discuss the basic calculational concepts to simulate
particle physics events at high energy colliders. We will mainly focus on the
physics in hadron colliders and particularly on the simulation of the
perturbative parts, where we will in turn focus on the next-to-leading order
QCD corrections.
| [
{
"created": "Wed, 26 Nov 2014 18:12:32 GMT",
"version": "v1"
}
] | 2014-11-27 | [
[
"Reuschle",
"Christian",
""
]
] | In this article we will discuss the basic calculational concepts to simulate particle physics events at high energy colliders. We will mainly focus on the physics in hadron colliders and particularly on the simulation of the perturbative parts, where we will in turn focus on the next-to-leading order QCD corrections. |
2308.07297 | Bruno Miguel Silva De Oliveira | Stefan Antusch, Jan Hajer and Bruno M. S. Oliveira | Heavy neutrino-antineutrino oscillations at the FCC-ee | 14 pages, 3 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We discuss the impact of heavy neutrino-antineutrino oscillations (NNOs) on
heavy neutral lepton (HNL) searches at proposed electron-positron colliders
such as the future circular $e^+e^-$ collider (FCC-ee). During the $Z$ pole
run, HNLs can be produced alongside a light neutrino or antineutrino that
escapes detection and can decay into a charged lepton or antilepton together
with an off-shell $W$ boson. In this case, signals of lepton number violation
only show up in the final state distributions. We discuss how NNOs, a typical
feature of collider-testable low-scale seesaw models where the heavy neutrinos
form pseudo-Dirac pairs, modify such final state distributions. For example,
the forward-backward asymmetry (FBA) of the reconstructed heavy (anti)neutrinos
develops an oscillatory dependence on the HNL lifetime. We show that these
oscillations can be resolvable for long-lived HNLs. We also discuss that when
the NNOs are not resolvable, they can nevertheless significantly modify the
theory predictions for FBAs and observables such as the ratio of the total
number of HNL decays into $\ell^-$ over ones into $\ell^+$, in an interval of
the angle~$\theta$ between the HNL and the beam axis. Our results show that
NNOs should be included in collider simulations of HNLs at the FCCee.
| [
{
"created": "Mon, 14 Aug 2023 17:32:59 GMT",
"version": "v1"
}
] | 2023-08-15 | [
[
"Antusch",
"Stefan",
""
],
[
"Hajer",
"Jan",
""
],
[
"Oliveira",
"Bruno M. S.",
""
]
] | We discuss the impact of heavy neutrino-antineutrino oscillations (NNOs) on heavy neutral lepton (HNL) searches at proposed electron-positron colliders such as the future circular $e^+e^-$ collider (FCC-ee). During the $Z$ pole run, HNLs can be produced alongside a light neutrino or antineutrino that escapes detection and can decay into a charged lepton or antilepton together with an off-shell $W$ boson. In this case, signals of lepton number violation only show up in the final state distributions. We discuss how NNOs, a typical feature of collider-testable low-scale seesaw models where the heavy neutrinos form pseudo-Dirac pairs, modify such final state distributions. For example, the forward-backward asymmetry (FBA) of the reconstructed heavy (anti)neutrinos develops an oscillatory dependence on the HNL lifetime. We show that these oscillations can be resolvable for long-lived HNLs. We also discuss that when the NNOs are not resolvable, they can nevertheless significantly modify the theory predictions for FBAs and observables such as the ratio of the total number of HNL decays into $\ell^-$ over ones into $\ell^+$, in an interval of the angle~$\theta$ between the HNL and the beam axis. Our results show that NNOs should be included in collider simulations of HNLs at the FCCee. |
1612.02911 | Xiaohui Liu | Radja Boughezal, Xiaohui Liu and Frank Petriello | Power Corrections in the N-jettiness Subtraction Scheme | 15 pages, 4 figures, references added, version to appear in JHEP | Journal of High Energy Physics (2017) 2017: 160 | 10.1007/JHEP03(2017)160 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the leading-logarithmic power corrections in the $N$-jettiness
subtraction scheme for higher-order perturbative QCD calculations. We compute
the next-to-leading order power corrections for an arbitrary $N$-jet process,
and we explicitly calculate the power correction through
next-to-next-to-leading order for color-singlet production for both $q\bar{q}$
and $gg$ initiated processes. Our results are compact and simple to implement
numerically. Including the leading power correction in the $N$-jettiness
subtraction scheme substantially improves its numerical efficiency. We discuss
what features of our techniques extend to processes containing final-state
jets.
| [
{
"created": "Fri, 9 Dec 2016 04:24:21 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Apr 2017 00:06:41 GMT",
"version": "v2"
}
] | 2017-04-05 | [
[
"Boughezal",
"Radja",
""
],
[
"Liu",
"Xiaohui",
""
],
[
"Petriello",
"Frank",
""
]
] | We discuss the leading-logarithmic power corrections in the $N$-jettiness subtraction scheme for higher-order perturbative QCD calculations. We compute the next-to-leading order power corrections for an arbitrary $N$-jet process, and we explicitly calculate the power correction through next-to-next-to-leading order for color-singlet production for both $q\bar{q}$ and $gg$ initiated processes. Our results are compact and simple to implement numerically. Including the leading power correction in the $N$-jettiness subtraction scheme substantially improves its numerical efficiency. We discuss what features of our techniques extend to processes containing final-state jets. |
2309.05923 | Fu-Hu Liu | Jia-Yu Chen, Mai-Ying Duan, Fu-Hu Liu, Khusniddin K. Olimov | Extracting Kinetic Freeze-out Properties in High Energy Collisions Using
a Multi-source Thermal Model | 18 pages, 8 figures. Advances in High Energy Physics, accepted | Advances in High Energy Physics 2024, 9938669 (2024) (14 pages) | 10.1155/2024/9938669 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the transverse momentum ($p_T$) spectra of neutral pions and
identified charged hadrons produced in proton--proton ($pp$), deuteron--gold
($d$--Au), and gold--gold (Au--Au) collisions at the center of mass energy
$\sqrt{s_{NN}}=200$ GeV. The study is made in the framework of a multi-source
thermal model used in the partonic level. It is assumed that the contribution
to the $p_T$-value of any hadron comes from two or three partons with an
isotropic distribution of the azimuthal angle. The contribution of each parton
to the $p_T$-value of a given hadron is assumed to obey any one of the standard
(Maxwell-Boltzmann, Fermi-Dirac, and Bose-Einstein) distributions with the
kinetic freeze-out temperature and average transverse flow velocity. The
$p_T$-spectra of the final-state hadrons can be fitted by the superposition of
two or three components. The results obtained from our Monte Carlo method are
used to fit the experimental results of the PHENIX and STAR Collaborations. The
results of present work serve as a suitable reference baseline for other
experiments and simulation studies.
| [
{
"created": "Tue, 12 Sep 2023 02:39:45 GMT",
"version": "v1"
},
{
"created": "Sun, 25 Feb 2024 03:28:05 GMT",
"version": "v2"
}
] | 2024-03-27 | [
[
"Chen",
"Jia-Yu",
""
],
[
"Duan",
"Mai-Ying",
""
],
[
"Liu",
"Fu-Hu",
""
],
[
"Olimov",
"Khusniddin K.",
""
]
] | We study the transverse momentum ($p_T$) spectra of neutral pions and identified charged hadrons produced in proton--proton ($pp$), deuteron--gold ($d$--Au), and gold--gold (Au--Au) collisions at the center of mass energy $\sqrt{s_{NN}}=200$ GeV. The study is made in the framework of a multi-source thermal model used in the partonic level. It is assumed that the contribution to the $p_T$-value of any hadron comes from two or three partons with an isotropic distribution of the azimuthal angle. The contribution of each parton to the $p_T$-value of a given hadron is assumed to obey any one of the standard (Maxwell-Boltzmann, Fermi-Dirac, and Bose-Einstein) distributions with the kinetic freeze-out temperature and average transverse flow velocity. The $p_T$-spectra of the final-state hadrons can be fitted by the superposition of two or three components. The results obtained from our Monte Carlo method are used to fit the experimental results of the PHENIX and STAR Collaborations. The results of present work serve as a suitable reference baseline for other experiments and simulation studies. |
2009.08183 | Hai-Qing Zhou | Zhong-Hua Zhao, Hui-Yun Cao, Hai-Qing Zhou | Two-photon exchange effects in $e^+ e^-\rightarrow\pi^+\pi^-$ at small $
\sqrt{s}$ | 8 figures | Phys. Rev. C 102, 035204 (2020) | 10.1103/PhysRevC.102.035204 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, the two-photon-exchange (TPE) effects in $e^+e^- \rightarrow
\pi^+ \pi^-$ at small $\sqrt{s}$ are discussed within a hadronic model. In the
limit $m_e\rightarrow 0$, the TPE contribution to the amplitude can be
described by one scalar function $\overline{c}_{1}^{(2\gamma)}$. The ratio
between this function and the corresponding contribution in one-photon exchange
$c_{1}^{(1\gamma)}$ reflects all the information of the TPE corrections. The
numerical results on this ratio are presented and an artificial function is
used to fit the numerical results. The latter can be used conveniently in the
further experimental data analysis. The numerical results show the asymmetry of
the differential cross sections in $e^+e^- \rightarrow \pi^+ \pi^-$ is about
$-4\%$ at $\sqrt{s}\sim 0.7$ GeV.
| [
{
"created": "Thu, 17 Sep 2020 09:50:42 GMT",
"version": "v1"
}
] | 2020-09-30 | [
[
"Zhao",
"Zhong-Hua",
""
],
[
"Cao",
"Hui-Yun",
""
],
[
"Zhou",
"Hai-Qing",
""
]
] | In this work, the two-photon-exchange (TPE) effects in $e^+e^- \rightarrow \pi^+ \pi^-$ at small $\sqrt{s}$ are discussed within a hadronic model. In the limit $m_e\rightarrow 0$, the TPE contribution to the amplitude can be described by one scalar function $\overline{c}_{1}^{(2\gamma)}$. The ratio between this function and the corresponding contribution in one-photon exchange $c_{1}^{(1\gamma)}$ reflects all the information of the TPE corrections. The numerical results on this ratio are presented and an artificial function is used to fit the numerical results. The latter can be used conveniently in the further experimental data analysis. The numerical results show the asymmetry of the differential cross sections in $e^+e^- \rightarrow \pi^+ \pi^-$ is about $-4\%$ at $\sqrt{s}\sim 0.7$ GeV. |
2212.11308 | Barmak Shams Es Haghi | Barmak Shams Es Haghi | Baryogenesis and Primordial Black Hole Dark Matter from Heavy Metastable
Particles | 11 pages, 1 figure | null | null | UTWI-19-2022 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel and simple scenario to explain baryon asymmetry and dark
matter (DM) by utilizing an early matter-dominated era (EMDE) caused by a heavy
metastable particle. Within the EMDE, lack of pressure enhances the formation
of primordial black holes (PBHs) which can then contribute to the relic
abundance of DM. The eventual decay of heavy metastable particle that has
baryon number and $CP$ violating interactions reheats the Universe and gives
rise to baryon asymmetry. Since in this setup, PBH serves as a DM candidate,
the particle physics model may not require new stable degrees of freedom which
leads to more freedom in the model-building side. As an example, we show that a
modulus field which dominates the energy density of the Universe prior to its
decay, may explain both DM and baryon asymmetry in the Universe in the context
of the Minimal Supersymmetric Standard Model (MSSM) while the lightest
superparticle is not stable and cannot be a DM candidate due to the R-parity
violating interactions needed for baryogenesis.
| [
{
"created": "Wed, 21 Dec 2022 19:07:50 GMT",
"version": "v1"
}
] | 2024-04-17 | [
[
"Haghi",
"Barmak Shams Es",
""
]
] | We propose a novel and simple scenario to explain baryon asymmetry and dark matter (DM) by utilizing an early matter-dominated era (EMDE) caused by a heavy metastable particle. Within the EMDE, lack of pressure enhances the formation of primordial black holes (PBHs) which can then contribute to the relic abundance of DM. The eventual decay of heavy metastable particle that has baryon number and $CP$ violating interactions reheats the Universe and gives rise to baryon asymmetry. Since in this setup, PBH serves as a DM candidate, the particle physics model may not require new stable degrees of freedom which leads to more freedom in the model-building side. As an example, we show that a modulus field which dominates the energy density of the Universe prior to its decay, may explain both DM and baryon asymmetry in the Universe in the context of the Minimal Supersymmetric Standard Model (MSSM) while the lightest superparticle is not stable and cannot be a DM candidate due to the R-parity violating interactions needed for baryogenesis. |
1902.09160 | Harleen Dahiya Dr. | Nisha Dhiman, Harleen Dahiya, Chueng-Ryong Ji, and Ho-Meoyng Choi | Twist-2 Pseudoscalar and Vector Meson Distribution Amplitudes in
Light-Front Quark Model with Exponential-type Confining Potential | 32 pages, 9 figures | Phys. Rev. D 100, 014026 (2019) | 10.1103/PhysRevD.100.014026 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the twist-2 distribution amplitudes (DAs) and the decay constants of
pseudoscalar light ($\pi$, $K$) and heavy ($D$, $D_s$, $B$, $B_s$) mesons as
well as the longitudinally and transversely polarized vector light ($\rho$,
$K^*$) and heavy ($D^*$, $D_s^*$, $B^*$, $B_s^*$) mesons in the light-front
quark model with the Coulomb plus exponential-type confining potential $V_{\rm
{exp}} = a + b e^{\alpha r}$ in addition to the hyperfine interaction. We first
compute the mass spectra of ground state pseudoscalar and vector light and
heavy mesons and fix the model parameters necessary for the analysis, applying
the variational principle with the trial wave function up to the first three
lowest order harmonic oscillator (HO) wave functions $\Phi(x, \textbf{k}_\bot)
= \sum_{n=1}^{3} c_n \phi_{nS}$. We then obtain the numerical results for the
corresponding decay constants of light and heavy mesons. We estimate the DAs,
analyze their variation as a function of momentum fraction and compute the
first six $\xi$-moments of the $B$ and $D$ mesons as well. We compare our
results with the available experimental data as well as with the other
theoretical model predictions.
| [
{
"created": "Mon, 25 Feb 2019 09:27:40 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Jul 2019 11:23:11 GMT",
"version": "v2"
}
] | 2019-07-31 | [
[
"Dhiman",
"Nisha",
""
],
[
"Dahiya",
"Harleen",
""
],
[
"Ji",
"Chueng-Ryong",
""
],
[
"Choi",
"Ho-Meoyng",
""
]
] | We study the twist-2 distribution amplitudes (DAs) and the decay constants of pseudoscalar light ($\pi$, $K$) and heavy ($D$, $D_s$, $B$, $B_s$) mesons as well as the longitudinally and transversely polarized vector light ($\rho$, $K^*$) and heavy ($D^*$, $D_s^*$, $B^*$, $B_s^*$) mesons in the light-front quark model with the Coulomb plus exponential-type confining potential $V_{\rm {exp}} = a + b e^{\alpha r}$ in addition to the hyperfine interaction. We first compute the mass spectra of ground state pseudoscalar and vector light and heavy mesons and fix the model parameters necessary for the analysis, applying the variational principle with the trial wave function up to the first three lowest order harmonic oscillator (HO) wave functions $\Phi(x, \textbf{k}_\bot) = \sum_{n=1}^{3} c_n \phi_{nS}$. We then obtain the numerical results for the corresponding decay constants of light and heavy mesons. We estimate the DAs, analyze their variation as a function of momentum fraction and compute the first six $\xi$-moments of the $B$ and $D$ mesons as well. We compare our results with the available experimental data as well as with the other theoretical model predictions. |
hep-ph/9306283 | null | R.N.Mohapatra (Department of Physics,University of Maryland, College
Park,Md) | Massive Neutrinos as Probe of Higher Unification | 22 pages,UMD-PP-93-208 | null | null | null | hep-ph | null | There are strong indications for neutrino masses and mixings in the data on
solar neutrinos as well as in the observed deficit of muon neutrinos from the
atmosphere. The COBE data and other analysis of the large scale structure in
the Universe also seems to require a hot component in the universe's dark
matter, which can be interpreted as a massive neutrino with mass in the few eV
range. Non-zero neutrino mass is a strong indication of a new local $B-L$
symmetry of electro-weak interactions . In particular, it is noted that the
simplest picture based on the left-right symmetric unification with a high
scale for the $B-L$ symmetry (as well as the scale of the right-handed gauge
boson $W_R$) as required by the constraints of grandunification and present LEP
data in a minimal $SO(10)$ model, can accomodate the solar neutrino data and a
weak hot dark matter neutrino but not the atmospheric neutrino puzzle. A model
with low scale $W_R$ ( in the TeV range) where the Dirac mass of the neutrino
arises at the one loop level can also do the same job. The low $W_R$ picture
can be tested in many rare decay experiments.
| [
{
"created": "Thu, 17 Jun 1993 16:55:00 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mohapatra",
"R. N.",
"",
"Department of Physics,University of Maryland, College\n Park,Md"
]
] | There are strong indications for neutrino masses and mixings in the data on solar neutrinos as well as in the observed deficit of muon neutrinos from the atmosphere. The COBE data and other analysis of the large scale structure in the Universe also seems to require a hot component in the universe's dark matter, which can be interpreted as a massive neutrino with mass in the few eV range. Non-zero neutrino mass is a strong indication of a new local $B-L$ symmetry of electro-weak interactions . In particular, it is noted that the simplest picture based on the left-right symmetric unification with a high scale for the $B-L$ symmetry (as well as the scale of the right-handed gauge boson $W_R$) as required by the constraints of grandunification and present LEP data in a minimal $SO(10)$ model, can accomodate the solar neutrino data and a weak hot dark matter neutrino but not the atmospheric neutrino puzzle. A model with low scale $W_R$ ( in the TeV range) where the Dirac mass of the neutrino arises at the one loop level can also do the same job. The low $W_R$ picture can be tested in many rare decay experiments. |
1111.7278 | Robert Szafron | Janusz Gluza and Robert Szafron | Real and complex random neutrino mass matrices and theta13 | v3: Discussion about 3+1 scenario extended, fig 5,6 added | null | 10.1103/PhysRevD.85.047701 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently it has been shown that one of the basic parameters of the neutrino
sector, so called theta13 angle is very small, but quite probably non-zero. We
argue that the small value of theta13 can still be reproduced easily by a wide
spectrum of randomly generated models of neutrino masses. For that we consider
real and complex neutrino mass matrices, also including sterile neutrinos. A
qualitative difference between results for real and complex mass matrices in
the region of small theta13 values is observed. We show that statistically the
present experimental data prefers random models of neutrino masses with sterile
neutrinos.
| [
{
"created": "Wed, 30 Nov 2011 19:25:29 GMT",
"version": "v1"
},
{
"created": "Sat, 3 Dec 2011 19:47:42 GMT",
"version": "v2"
},
{
"created": "Tue, 3 Jan 2012 13:26:37 GMT",
"version": "v3"
}
] | 2013-05-30 | [
[
"Gluza",
"Janusz",
""
],
[
"Szafron",
"Robert",
""
]
] | Recently it has been shown that one of the basic parameters of the neutrino sector, so called theta13 angle is very small, but quite probably non-zero. We argue that the small value of theta13 can still be reproduced easily by a wide spectrum of randomly generated models of neutrino masses. For that we consider real and complex neutrino mass matrices, also including sterile neutrinos. A qualitative difference between results for real and complex mass matrices in the region of small theta13 values is observed. We show that statistically the present experimental data prefers random models of neutrino masses with sterile neutrinos. |
hep-ph/0305131 | Alicia Broncano | A.Broncano | An effective theory for Leptogenesis | 6 pages. Based on the talk given at the XXXVIII Rencontres de Moriond
(Electroweak Session) | null | null | null | hep-ph | null | The effective Lagrangian for the seesaw model is derived. Besides the usual
dimension-5 operator responsible for light neutrino masses, a dimension-6
operator is included which, for three or less heavy neutrino generations,
provides a generic link between low-energy observables and all physical
parameters of the high-energy seesaw Lagrangian. Leptogenesis can be then
confirmed or ruled out through the measurement of neutrino masses and mixings
and the exotic neutrino couplings originated from the dimension-6 operator.
| [
{
"created": "Tue, 13 May 2003 17:37:36 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Broncano",
"A.",
""
]
] | The effective Lagrangian for the seesaw model is derived. Besides the usual dimension-5 operator responsible for light neutrino masses, a dimension-6 operator is included which, for three or less heavy neutrino generations, provides a generic link between low-energy observables and all physical parameters of the high-energy seesaw Lagrangian. Leptogenesis can be then confirmed or ruled out through the measurement of neutrino masses and mixings and the exotic neutrino couplings originated from the dimension-6 operator. |
1405.1975 | Alexander Spencer-Smith | Alexander Spencer-Smith | Higgs Vacuum Stability in a Mass-Dependent Renormalisation Scheme | 19 pages, 2 figures | null | null | null | hep-ph gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using a physical renormalisation scheme we derive mass-dependent
renormalisation group equations for the running of the Higgs quartic coupling
within the Standard Model. Subsequently, we accurately take into account weak
scale thresholds, resulting in a reduction of the error in the determination of
the maximum $M_t$ required for absolute stability of the vacuum to 0.28 GeV.
For the first time, we conclusively establish the fate of the electroweak
vacuum, finding that absolute stability of the Higgs vacuum state is excluded
at 99.98% C.L. We also discuss the consequences when this new result is
combined with the BICEP Collaboration's recent observation of B-mode
polarisation in the cosmic microwave background, finding the Standard Model
electroweak vacuum lifetime to be too short to have survived inflation. The
implications for inflationary and new physics models are also discussed.
| [
{
"created": "Thu, 8 May 2014 15:37:13 GMT",
"version": "v1"
},
{
"created": "Thu, 24 Jul 2014 02:45:23 GMT",
"version": "v2"
}
] | 2014-07-25 | [
[
"Spencer-Smith",
"Alexander",
""
]
] | Using a physical renormalisation scheme we derive mass-dependent renormalisation group equations for the running of the Higgs quartic coupling within the Standard Model. Subsequently, we accurately take into account weak scale thresholds, resulting in a reduction of the error in the determination of the maximum $M_t$ required for absolute stability of the vacuum to 0.28 GeV. For the first time, we conclusively establish the fate of the electroweak vacuum, finding that absolute stability of the Higgs vacuum state is excluded at 99.98% C.L. We also discuss the consequences when this new result is combined with the BICEP Collaboration's recent observation of B-mode polarisation in the cosmic microwave background, finding the Standard Model electroweak vacuum lifetime to be too short to have survived inflation. The implications for inflationary and new physics models are also discussed. |
1810.03281 | V. E. Troitsky | A.F. Krutov, V.E. Troitsky | Quadrupole moments of spin-1 systems: the rho meson, the S-wave deuteron
and some general constraints | 12 pages (revtex twocolumn), 7 figures | Phys. Rev. D 99, 014036 (2019) | 10.1103/PhysRevD.99.014036 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We costruct the relativistic operator of the quadrupole moment of
two-particle composite spin one systems with zero orbital moment of the
relative motion and derive explicit analytical expression for the quadrupole
moment using the approach to relativistic composite systems based on our
version of the instant-form relativistic quantum mechanics (RQM). We calculate
the quadrupole moments of the rho meson and of the S-wave deuteron without any
free parameters, using our unified pi&rho model (Phys. Rev.D 93, 036007 (2016);
97, 033007 (2018)) and our previous results on deuteron. Our calculation gives
Q_rho=-0.158+-0.04 GeV^-2 and Q_d=-1.4*10^-4 GeV^-2. Having in our disposition
the rather general form of the quadrupole-moment operator we for the first time
formulate the problem of the upper and lower bounds for possible values of the
quadrupole moment of a two-particle system with indicated quantum numbers for a
large range of constituent masses, and partially solve it.
| [
{
"created": "Mon, 8 Oct 2018 06:44:16 GMT",
"version": "v1"
}
] | 2019-01-30 | [
[
"Krutov",
"A. F.",
""
],
[
"Troitsky",
"V. E.",
""
]
] | We costruct the relativistic operator of the quadrupole moment of two-particle composite spin one systems with zero orbital moment of the relative motion and derive explicit analytical expression for the quadrupole moment using the approach to relativistic composite systems based on our version of the instant-form relativistic quantum mechanics (RQM). We calculate the quadrupole moments of the rho meson and of the S-wave deuteron without any free parameters, using our unified pi&rho model (Phys. Rev.D 93, 036007 (2016); 97, 033007 (2018)) and our previous results on deuteron. Our calculation gives Q_rho=-0.158+-0.04 GeV^-2 and Q_d=-1.4*10^-4 GeV^-2. Having in our disposition the rather general form of the quadrupole-moment operator we for the first time formulate the problem of the upper and lower bounds for possible values of the quadrupole moment of a two-particle system with indicated quantum numbers for a large range of constituent masses, and partially solve it. |
1410.2431 | Pedro Jimenez-Delgado | Pedro Jimenez-Delgado | Delineating the polarized and unpolarized partonic structure of the
nucleon | Proceedings of Light Cone 2014, Proceedings of QCD Evolution 2014, 6
pages, 5 figures | null | 10.1007/s00601-015-0953-4 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Reports on our latest extractions of parton distribution functions of the
nucleon are given. First an overview of the recent JR14 upgrade of our
unpolarized PDFs, including NNLO determinations of the strong coupling constant
and a discussion of the role of the input scale in parton distribution
analysis. In the second part of the talk recent results on the determination of
spin-dependent PDFs from the JAM collaboration are reported, including a
careful treatment of hadronic and nuclear corrections, as well as reports on
the impact of present and future data in our understanding of the spin of the
nucleon.
| [
{
"created": "Thu, 9 Oct 2014 11:54:32 GMT",
"version": "v1"
}
] | 2015-06-23 | [
[
"Jimenez-Delgado",
"Pedro",
""
]
] | Reports on our latest extractions of parton distribution functions of the nucleon are given. First an overview of the recent JR14 upgrade of our unpolarized PDFs, including NNLO determinations of the strong coupling constant and a discussion of the role of the input scale in parton distribution analysis. In the second part of the talk recent results on the determination of spin-dependent PDFs from the JAM collaboration are reported, including a careful treatment of hadronic and nuclear corrections, as well as reports on the impact of present and future data in our understanding of the spin of the nucleon. |
hep-ph/9409401 | Li Xiao-yuan | Xiaoyuan Li and Yi Liao | Renormalization of the Electroweak Theory in the Background Field Method | 12 pages with 2 figures available on request (Lixy@itp.ac.cn), Latex,
ASITP-94-50 | null | null | null | hep-ph | null | The applicability of the background field method in spontaneously broken
gauge theories is examined with new features emphasized. An explicit one loop
analysis in the electroweak theory shows that the method can be consistently
implemented in the on-shell renormalization scheme, and that the choice of the
background gauge cannot be arbitrary and must be fixed in the Landau gauge if
one calculates scattering amplitudes involving unphysical Goldstone bosons.
Some possible applications are also briefly indicated.
| [
{
"created": "Sat, 24 Sep 1994 16:48:46 GMT",
"version": "v1"
}
] | 2009-09-25 | [
[
"Li",
"Xiaoyuan",
""
],
[
"Liao",
"Yi",
""
]
] | The applicability of the background field method in spontaneously broken gauge theories is examined with new features emphasized. An explicit one loop analysis in the electroweak theory shows that the method can be consistently implemented in the on-shell renormalization scheme, and that the choice of the background gauge cannot be arbitrary and must be fixed in the Landau gauge if one calculates scattering amplitudes involving unphysical Goldstone bosons. Some possible applications are also briefly indicated. |
1106.1719 | Michael Gustafsson Dr | Michael Gustafsson | The Inert Doublet Model and its Phenomenology | Conference proceedings from Third International Workshop on Prospects
for Charged Higgs Discovery at Colliders - CHARGED2010, September 27-30,
2010, Uppsala Sweden. Minor updates to published version. 10 pages, 1 figure | PoS Charged 2010:030, 2010 | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The single Higgs doublet in the standard model (SM) may be the simplest way
of introducing electroweak symmetry breaking, but SM extensions with more
scalar doublets are not excluded. A special case of the two Higgs doublet
models is the inert doublet model - a minimalistic version with interesting
phenomenology. These proceedings reviews the inert doublet model's theoretical
setup, constraints, collider prospects and its dark matter phenomenology.
| [
{
"created": "Thu, 9 Jun 2011 07:24:10 GMT",
"version": "v1"
}
] | 2011-06-10 | [
[
"Gustafsson",
"Michael",
""
]
] | The single Higgs doublet in the standard model (SM) may be the simplest way of introducing electroweak symmetry breaking, but SM extensions with more scalar doublets are not excluded. A special case of the two Higgs doublet models is the inert doublet model - a minimalistic version with interesting phenomenology. These proceedings reviews the inert doublet model's theoretical setup, constraints, collider prospects and its dark matter phenomenology. |
0705.3533 | Takayuki Hirayama | Takayuki Hirayama, Koichi Yoshioka | Holographic Construction of Technicolor Theory | 23 pages; references added, minor changes | JHEP 0710:002,2007 | 10.1088/1126-6708/2007/10/002 | null | hep-ph hep-th | null | We construct a dual description of technicolor theory based on the D4/D8
brane configuration. A strongly-coupled technicolor theory is identified as the
effective theory on D-branes, and from the gauge/gravity correspondence, we
explore the weakly-coupled holographic description of dynamical electroweak
symmetry breaking. It is found from the D-brane probe action that the masses of
W and Z bosons are given by the decay constant of technipion, and the
technimesons become hierarchically heavy. Moreover, the couplings of heavier
modes to standard model fermions are rather suppressed. The oblique correction
parameters are also evaluated and found to be small except for the S parameter,
which can be reduced by modifying the model. The fermion fields are introduced
at the intersections of D-branes and their masses are generated via massive
gauge bosons from open strings stretching between D-branes.
| [
{
"created": "Thu, 24 May 2007 09:07:09 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Sep 2007 11:55:35 GMT",
"version": "v2"
}
] | 2009-04-21 | [
[
"Hirayama",
"Takayuki",
""
],
[
"Yoshioka",
"Koichi",
""
]
] | We construct a dual description of technicolor theory based on the D4/D8 brane configuration. A strongly-coupled technicolor theory is identified as the effective theory on D-branes, and from the gauge/gravity correspondence, we explore the weakly-coupled holographic description of dynamical electroweak symmetry breaking. It is found from the D-brane probe action that the masses of W and Z bosons are given by the decay constant of technipion, and the technimesons become hierarchically heavy. Moreover, the couplings of heavier modes to standard model fermions are rather suppressed. The oblique correction parameters are also evaluated and found to be small except for the S parameter, which can be reduced by modifying the model. The fermion fields are introduced at the intersections of D-branes and their masses are generated via massive gauge bosons from open strings stretching between D-branes. |
1302.4496 | Yanrui Liu | W. Zhu, Yan-Rui Liu, T. Yao | Is $J^{PC}=3^{-+}$ molecule possible? | null | null | 10.1088/1674-1137/39/2/023101 | null | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The confirmation of charged charmonium-like states indiates that heavy quark
molecules should exist. We here discuss the possibility of a molecule state
with $J^{PC}=3^{-+}$. In a one-boson-exchange model investigation for the S
wave $C=+$ $D^*\bar{D}_2^*$ states, one finds that the strongest attraction is
in the case $J=3$ and $I=0$ for both $\pi$ and $\sigma$ exchanges. Numerical
analysis indicates that this hadronic bound state might exist if a
phenomenological cutoff parameter around 2.3 GeV (1.5 GeV) is reasonable with a
dipole (monopole) type form factor in the one-pion-exchange model. The cutoff
for binding solutions may be reduced to a smaller value once the $\sigma$
exchange contribution is included. If a state around the $D^*\bar{D}_2^*$
threshold ($\approx$4472 MeV) in the channel $J/\psi\omega$ (P wave) is
observed, the heavy quark spin symmetry implies that it is not a $c\bar{c}$
meson and the $J^{PC}$ are likely to be $3^{-+}$.
| [
{
"created": "Tue, 19 Feb 2013 01:03:56 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Jun 2014 21:39:50 GMT",
"version": "v2"
}
] | 2015-06-15 | [
[
"Zhu",
"W.",
""
],
[
"Liu",
"Yan-Rui",
""
],
[
"Yao",
"T.",
""
]
] | The confirmation of charged charmonium-like states indiates that heavy quark molecules should exist. We here discuss the possibility of a molecule state with $J^{PC}=3^{-+}$. In a one-boson-exchange model investigation for the S wave $C=+$ $D^*\bar{D}_2^*$ states, one finds that the strongest attraction is in the case $J=3$ and $I=0$ for both $\pi$ and $\sigma$ exchanges. Numerical analysis indicates that this hadronic bound state might exist if a phenomenological cutoff parameter around 2.3 GeV (1.5 GeV) is reasonable with a dipole (monopole) type form factor in the one-pion-exchange model. The cutoff for binding solutions may be reduced to a smaller value once the $\sigma$ exchange contribution is included. If a state around the $D^*\bar{D}_2^*$ threshold ($\approx$4472 MeV) in the channel $J/\psi\omega$ (P wave) is observed, the heavy quark spin symmetry implies that it is not a $c\bar{c}$ meson and the $J^{PC}$ are likely to be $3^{-+}$. |
1309.5763 | Alexandre Kisselev | A.V. Kisselev | Randall-Sundrum scenario with small curvature and dilepton production at
LHC | 8 pages, 8 figures, to appear in the Proceedings of the International
School-Seminar "New Physics and Quantum Chromodynamics at External
Conditions", May 22-24, 2013, Dnipropetrovsk, Ukraine | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The brief review of the recent results obtained in the Randall-Sundrum
scenario with the small curvature of the five-dimensional space-time is
presented.
| [
{
"created": "Mon, 23 Sep 2013 11:06:00 GMT",
"version": "v1"
}
] | 2013-09-24 | [
[
"Kisselev",
"A. V.",
""
]
] | The brief review of the recent results obtained in the Randall-Sundrum scenario with the small curvature of the five-dimensional space-time is presented. |
hep-ph/0201070 | Giulio D'Agostini | G. D'Agostini | Minimum Bias Legacy of Search Results | Talk given at the Seventh Topical Seminar on ``The legacy of LEP and
SLC '', Siena, Italy, 8-11 October 2001. This paper and related work are also
available at http://www-zeus.roma1.infn.it/~agostini/prob+stat.html | Nucl.Phys.Proc.Suppl. 109B (2002) 148-152 | 10.1016/S0920-5632(02)90025-3 | null | hep-ph physics.data-an | null | The end of LEP and SLC is a good moment to review the way to summarize search
results in order to exploit at best, in future analyses and speculations, the
pieces of information coming from all experiments. Some known problems with the
usual way of reporting results in terms ``CL limits'' are shortly recalled, and
a plea is formulated to publish just parametrized likelihoods, possibly
rescaled to the asymptotic insensitivity limit level.
| [
{
"created": "Thu, 10 Jan 2002 02:13:02 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"D'Agostini",
"G.",
""
]
] | The end of LEP and SLC is a good moment to review the way to summarize search results in order to exploit at best, in future analyses and speculations, the pieces of information coming from all experiments. Some known problems with the usual way of reporting results in terms ``CL limits'' are shortly recalled, and a plea is formulated to publish just parametrized likelihoods, possibly rescaled to the asymptotic insensitivity limit level. |
hep-ph/9901204 | Jihn E. Kim | Jihn E. Kim | A natural solution of $\mu$ from the hidden sector | LaTex file, 11 pages | Phys.Lett. B452 (1999) 255-259 | 10.1016/S0370-2693(99)00289-0 | null | hep-ph | null | The $\mu$ parameter is calculated in supergravity models possessing the
$U(1)_A\times U(1)_R$ symmetry. In one natural model without a free mass
parameter below the Planck scale, the symmetry breaking scale is identified as
the hidden sector squark condensation scale.
| [
{
"created": "Mon, 4 Jan 1999 16:37:25 GMT",
"version": "v1"
},
{
"created": "Thu, 25 Feb 1999 08:23:40 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kim",
"Jihn E.",
""
]
] | The $\mu$ parameter is calculated in supergravity models possessing the $U(1)_A\times U(1)_R$ symmetry. In one natural model without a free mass parameter below the Planck scale, the symmetry breaking scale is identified as the hidden sector squark condensation scale. |
1611.01432 | Thorben Graf | Thorben Graf and Peter Petreczky | Quark mass effects in quark number susceptibilities | 4 pages, 1 figure, Contribution to the proceedings of Hot Quarks 2016
conference at South Padre Island, TX, USA | null | 10.1088/1742-6596/832/1/012034 | null | hep-ph hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The quark degrees of freedom of the QGP with special focus on mass effects
are investigated. A next-to-leading-order perturbation theory approach with
quark mass dependence is applied and compared to lattice QCD results.
| [
{
"created": "Fri, 4 Nov 2016 16:09:22 GMT",
"version": "v1"
}
] | 2017-05-24 | [
[
"Graf",
"Thorben",
""
],
[
"Petreczky",
"Peter",
""
]
] | The quark degrees of freedom of the QGP with special focus on mass effects are investigated. A next-to-leading-order perturbation theory approach with quark mass dependence is applied and compared to lattice QCD results. |
0808.3787 | Wouter Waalewijn | Wouter J. Waalewijn | The Chiral Anomaly in SCET | 16 pages, 6 figures | Phys.Rev.D79:036003,2009 | 10.1103/PhysRevD.79.036003 | MIT-CTP-3976 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Anomalies are an infrared effect, but are often realized in effective
theories in a non-trivial way. We study the chiral anomaly in Soft Collinear
Effective Theory (SCET), where the anomaly equation has terms contributing at
different orders in the power expansion. The chiral anomaly equations in SCET
are computed up to NNLO in the power counting with external collinear and/or
ultrasoft gluons. We do this by expanding the QCD anomaly equation, using the
tree level (LO in \alpha_s) relations between QCD and SCET fields. The validity
of this correspondence between the anomaly equations is confirmed by direct
computation of the one-loop diagrams in SCET.
| [
{
"created": "Thu, 28 Aug 2008 13:49:38 GMT",
"version": "v1"
}
] | 2009-11-06 | [
[
"Waalewijn",
"Wouter J.",
""
]
] | Anomalies are an infrared effect, but are often realized in effective theories in a non-trivial way. We study the chiral anomaly in Soft Collinear Effective Theory (SCET), where the anomaly equation has terms contributing at different orders in the power expansion. The chiral anomaly equations in SCET are computed up to NNLO in the power counting with external collinear and/or ultrasoft gluons. We do this by expanding the QCD anomaly equation, using the tree level (LO in \alpha_s) relations between QCD and SCET fields. The validity of this correspondence between the anomaly equations is confirmed by direct computation of the one-loop diagrams in SCET. |
2404.17352 | Chui-Fan Kong | Shao-Feng Ge, Chui-Fan Kong, Alexei Y. Smirnov | Testing the Origins of Neutrino Mass with Supernova Neutrino Time Delay | 6 pages, 4 figures | null | null | null | hep-ph astro-ph.HE hep-ex | http://creativecommons.org/licenses/by/4.0/ | The origin of neutrino masses remains unknown. Both the vacuum mass and the
dark mass generated by the neutrino interactions with DM particles or fields
can fit the current oscillation data. The dark mass squared is proportional to
the DM number density and therefore varies on the galactic scale with much
larger values around the Galactic Center. This affects the group velocity and
the arrival time delay of core-collapse supernovae neutrinos. This time delay,
especially for the $\nu_e$ neutronization peak with a sharp time structure, can
be used to distinguish the vacuum and dark neutrino masses. For illustration,
we explore the potential of DUNE which is sensitive to $\nu_e$. Our simulations
show that DUNE can distinguish the two neutrino mass origins at more than
$5\sigma\,$C.L., depending on the observed local value of neutrino mass, the
neutrino mass ordering, the DM density profile, and the SN location.
| [
{
"created": "Fri, 26 Apr 2024 12:06:39 GMT",
"version": "v1"
}
] | 2024-04-29 | [
[
"Ge",
"Shao-Feng",
""
],
[
"Kong",
"Chui-Fan",
""
],
[
"Smirnov",
"Alexei Y.",
""
]
] | The origin of neutrino masses remains unknown. Both the vacuum mass and the dark mass generated by the neutrino interactions with DM particles or fields can fit the current oscillation data. The dark mass squared is proportional to the DM number density and therefore varies on the galactic scale with much larger values around the Galactic Center. This affects the group velocity and the arrival time delay of core-collapse supernovae neutrinos. This time delay, especially for the $\nu_e$ neutronization peak with a sharp time structure, can be used to distinguish the vacuum and dark neutrino masses. For illustration, we explore the potential of DUNE which is sensitive to $\nu_e$. Our simulations show that DUNE can distinguish the two neutrino mass origins at more than $5\sigma\,$C.L., depending on the observed local value of neutrino mass, the neutrino mass ordering, the DM density profile, and the SN location. |
1309.7536 | Jacek Syska Mr. | J. Syska, J. Dajka, and J. {\L}uczka | Interference phenomenon and geometric phase for Dirac neutrino in pion+
decay | 5 pages, 3 figures | Phys.Rev.D 87, 117302 (2013) | 10.1103/PhysRevD.87.117302 | null | hep-ph quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We analyze the geometric phase in the neutrino oscillation phenomenon, which
follows the pion decay \pi+ --> \mu+ + \nu_{\mu}. Its value \pi is consistent
with the present-day global analysis of the Standard Model neutrino oscillation
parameters, accounting for the nonzero value of \theta_13. The impact of the
charge-parity (CP) violating phase \delta, the neutrino's nature, and the new
physics is discussed.
| [
{
"created": "Sun, 29 Sep 2013 04:58:25 GMT",
"version": "v1"
}
] | 2015-04-06 | [
[
"Syska",
"J.",
""
],
[
"Dajka",
"J.",
""
],
[
"Łuczka",
"J.",
""
]
] | We analyze the geometric phase in the neutrino oscillation phenomenon, which follows the pion decay \pi+ --> \mu+ + \nu_{\mu}. Its value \pi is consistent with the present-day global analysis of the Standard Model neutrino oscillation parameters, accounting for the nonzero value of \theta_13. The impact of the charge-parity (CP) violating phase \delta, the neutrino's nature, and the new physics is discussed. |
hep-ph/0605226 | Satoshi Mishima | Satoshi Mishima | Hadronic B Decays in PQCD | Invited talk at Flavor Physics & CP Violation Conference, Vancouver,
2006; 5 pages, 2 figures | null | null | fpcp06_423 | hep-ph | null | I review recent progress on exclusive hadronic B meson decays in the
perturbative QCD approach, with focus on puzzles in the branching ratios and
the CP asymmetries of the B -> pi K and B -> pi pi modes, and polarization
fractions in B -> VV modes.
| [
{
"created": "Mon, 22 May 2006 03:40:49 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Mishima",
"Satoshi",
""
]
] | I review recent progress on exclusive hadronic B meson decays in the perturbative QCD approach, with focus on puzzles in the branching ratios and the CP asymmetries of the B -> pi K and B -> pi pi modes, and polarization fractions in B -> VV modes. |
1310.3183 | Ivica Picek | Vedran Brdar, Ivica Picek, Branimir Radovcic | Radiative Neutrino Mass with Scotogenic Scalar Triplet | 11 pages, 3 figures, matches published version | Phys. Lett. B 728 (2014) 198 | 10.1016/j.physletb.2013.11.045 | ZTF-EP-13-04 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present radiative one-loop neutrino mass model with hypercharge zero
scalar triplet in conjunction with another charged singlet scalar and an
additional vectorlike lepton doublet. We study three variants of this mass
model: the first one without additional beyond-SM symmetry, the second with
imposed DM-stabilizing discrete Z_2 symmetry, and the third in which this Z_2
symmetry is promoted to the gauge symmetry U(1)_D. The two latter cases are
scotogenic, with a neutral component of the scalar triplet as a dark matter
candidate. In first scotogenic model the Z_2-odd dark matter candidate is at
the multi-TeV mass scale, so that all new degrees of freedom are beyond the
direct reach of the LHC. In second scotogenic setup, with broken U(1)_D
symmetry the model may have LHC signatures or be relevant to astrophysical
observations, depending on the scale of U(1)_D breaking.
| [
{
"created": "Fri, 11 Oct 2013 16:01:44 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Dec 2013 10:41:58 GMT",
"version": "v2"
}
] | 2013-12-23 | [
[
"Brdar",
"Vedran",
""
],
[
"Picek",
"Ivica",
""
],
[
"Radovcic",
"Branimir",
""
]
] | We present radiative one-loop neutrino mass model with hypercharge zero scalar triplet in conjunction with another charged singlet scalar and an additional vectorlike lepton doublet. We study three variants of this mass model: the first one without additional beyond-SM symmetry, the second with imposed DM-stabilizing discrete Z_2 symmetry, and the third in which this Z_2 symmetry is promoted to the gauge symmetry U(1)_D. The two latter cases are scotogenic, with a neutral component of the scalar triplet as a dark matter candidate. In first scotogenic model the Z_2-odd dark matter candidate is at the multi-TeV mass scale, so that all new degrees of freedom are beyond the direct reach of the LHC. In second scotogenic setup, with broken U(1)_D symmetry the model may have LHC signatures or be relevant to astrophysical observations, depending on the scale of U(1)_D breaking. |
hep-ph/9610356 | null | S. De Curtis | Signatures of Dynamical Symmetry Breaking at Tevatron Upgrade and LHC | 9 pages, latex, 3 figures, needs sprocl.sty | null | null | null | hep-ph | null | We study the phenomenology of a strongly interacting electroweak symmetry
breaking sector in which the physics is dominated by spin one resonances.
Specifically we will consider an effective description of dynamical symmetry
breaking based on a particular model which passes all the low-energy precision
tests and gives clear signals at LHC but also at Tevatron Upgrade.
| [
{
"created": "Mon, 14 Oct 1996 18:42:52 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"De Curtis",
"S.",
""
]
] | We study the phenomenology of a strongly interacting electroweak symmetry breaking sector in which the physics is dominated by spin one resonances. Specifically we will consider an effective description of dynamical symmetry breaking based on a particular model which passes all the low-energy precision tests and gives clear signals at LHC but also at Tevatron Upgrade. |
0809.5092 | Arvind Rajaraman | Arvind Rajaraman | Aspects of Unparticle Physics | 4 pages, latex. Based on talk at ICHEP08 | null | 10.1063/1.3052052 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review some theoretical and experimental issues in unparticle physics,
focusing mainly on collider signatures.
| [
{
"created": "Mon, 29 Sep 2008 23:46:24 GMT",
"version": "v1"
},
{
"created": "Wed, 15 Oct 2008 20:27:07 GMT",
"version": "v2"
}
] | 2009-11-13 | [
[
"Rajaraman",
"Arvind",
""
]
] | We review some theoretical and experimental issues in unparticle physics, focusing mainly on collider signatures. |
hep-ph/0004086 | Lesgourgues | Julien Lesgourgues, Sergio Pastor, Marco Peloso, Lorenzo Sorbo | Cosmology of the Randall-Sundrum model after dilaton stabilization | 16 pages | Phys.Lett. B489 (2000) 411 | 10.1016/S0370-2693(00)00943-6 | SISSA 39/2000/EP | hep-ph astro-ph gr-qc hep-th | null | We provide the first complete analysis of cosmological evolution in the
Randall-Sundrum model with stabilized dilaton. We give the exact expansion law
for matter densities on the two branes with arbitrary equations of state. The
effective four-dimensional theory leads to standard cosmology at low energy.
The limit of validity of the low energy theory and possible deviations from the
ordinary expansion law in the high energy regime are finally discussed.
| [
{
"created": "Mon, 10 Apr 2000 17:01:09 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Lesgourgues",
"Julien",
""
],
[
"Pastor",
"Sergio",
""
],
[
"Peloso",
"Marco",
""
],
[
"Sorbo",
"Lorenzo",
""
]
] | We provide the first complete analysis of cosmological evolution in the Randall-Sundrum model with stabilized dilaton. We give the exact expansion law for matter densities on the two branes with arbitrary equations of state. The effective four-dimensional theory leads to standard cosmology at low energy. The limit of validity of the low energy theory and possible deviations from the ordinary expansion law in the high energy regime are finally discussed. |
1012.1597 | Enrico Nardi | Chee Sheng Fong, (YITP, Stony Brook), M.C. Gonzalez-Garcia, (ICREA,
Barcelona & Barcelona U., ECM & ICC, Barcelona U. & YITP, Stony Brook) and
Enrico Nardi, (Frascati & Madrid, Autonoma U. & Madrid, IFT) | Early Universe effective theories: The Soft Leptogenesis and R-Genesis
Cases | 41 pages, 5 figures, added 4 references | JCAP 1102:032,2011 | 10.1088/1475-7516/2011/02/032 | YITP-SB-10-42 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the effective theory appropriate for studying soft leptogenesis at
temperatures T>10^7 GeV. In this regime, the main source of the B-L asymmetry
is the CP asymmetry of a new anomalous R-charge that couple to generalized
anomalous electroweak processes. Baryogenesis thus occurs mainly through
R-genesis, and with an efficiency that can be up to two orders of magnitude
larger than in usual estimates. Contrary to common belief, a sizeable baryon
asymmetry is generated also when thermal corrections to the CP asymmetries in
sneutrino decays are neglected which, in soft leptogenesis, implyes vanishing
lepton-flavour CP asymmetries. We present general Boltzmann equations for soft
leptogenesis that are valid in all temperature regimes.
| [
{
"created": "Tue, 7 Dec 2010 21:00:01 GMT",
"version": "v1"
},
{
"created": "Sat, 26 Feb 2011 20:28:11 GMT",
"version": "v2"
}
] | 2015-03-17 | [
[
"Fong",
"Chee Sheng",
""
],
[
"Gonzalez-Garcia",
"M. C.",
""
],
[
"Nardi",
"Enrico",
""
]
] | We discuss the effective theory appropriate for studying soft leptogenesis at temperatures T>10^7 GeV. In this regime, the main source of the B-L asymmetry is the CP asymmetry of a new anomalous R-charge that couple to generalized anomalous electroweak processes. Baryogenesis thus occurs mainly through R-genesis, and with an efficiency that can be up to two orders of magnitude larger than in usual estimates. Contrary to common belief, a sizeable baryon asymmetry is generated also when thermal corrections to the CP asymmetries in sneutrino decays are neglected which, in soft leptogenesis, implyes vanishing lepton-flavour CP asymmetries. We present general Boltzmann equations for soft leptogenesis that are valid in all temperature regimes. |
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