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/0607306 | Bernd Kniehl | Bernd A. Kniehl, Gustav Kramer | Charmed-Hadron Fragmentation Functions from CERN LEP1 Revisited | 9 pages, 1 figure, DESY 06-102, to appear in Phys. Rev. D | Phys.Rev.D74:037502,2006 | 10.1103/PhysRevD.74.037502 | null | hep-ph | null | In Phys. Rev. D 58, 014014 (1998) and 71, 094013 (2005), we determined
non-perturbative D^0, D^+, D^{*+}, D_s^+, and Lambda_c^+ fragmentation
functions, both at leading and next-to-leading order in the MS-bar
factorization scheme, by fitting e^+e^- data taken by the OPAL Collaboration at
CERN LEP1. The starting points for the evolution in the factorization scale mu
were taken to be mu_0 = 2m_Q, where Q = c,b. For the reader's convenience, in
this Addendum, we repeat this analysis for mu_0 = m_Q, where the flavor
thresholds of modern sets of parton density functions are located.
| [
{
"created": "Thu, 27 Jul 2006 14:29:32 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Kniehl",
"Bernd A.",
""
],
[
"Kramer",
"Gustav",
""
]
] | In Phys. Rev. D 58, 014014 (1998) and 71, 094013 (2005), we determined non-perturbative D^0, D^+, D^{*+}, D_s^+, and Lambda_c^+ fragmentation functions, both at leading and next-to-leading order in the MS-bar factorization scheme, by fitting e^+e^- data taken by the OPAL Collaboration at CERN LEP1. The starting points for the evolution in the factorization scale mu were taken to be mu_0 = 2m_Q, where Q = c,b. For the reader's convenience, in this Addendum, we repeat this analysis for mu_0 = m_Q, where the flavor thresholds of modern sets of parton density functions are located. |
1312.3331 | Shaouly Bar-Shalom | Michael Geller, Shaouly Bar-Shalom, Amarjit Soni | Higgs-radion unification: radius stabilization by an SU(2) bulk doublet
and the 126 GeV scalar | latex, 23 pages, 2 figures, 2 tables. In V2: 2 figures and 1 table
added, new references added and differences with previous works are further
elaborated | Phys. Rev. D 89, 095015 (2014) | 10.1103/PhysRevD.89.095015 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate a Randall-Sundrum model with an SU(2) doublet propagating in
the bulk. Upon calculating its gravitational effect we find that a stabilized
radius can be generated without the use of an additional scalar, as needed for
example in the Goldberger-Wise (GW) mechanism, and with no additional
fine-tuning other than the inescapable one due to the cosmological constant;
similar tuning is also present in the GW mechanism. The lowest scalar
excitation in this scenario, the counterpart of the radion of the GW mechanism,
has both radion-like and Higgs-like couplings to the SM fields. It, thus, plays
a dual role and we, therefore, denote it as the "Higgs-radion" ($h_r$). As
opposed to the GW radion case, our Higgs-radion is found to be compatible with
the 126 GeV scalar recently discovered at the LHC, at the level of $1\sigma$,
with a resulting $95\%$ CL bound on the KK-gluon mass of: $4.48~TeV<M_{KKG}<
5.44~TeV$. An important consequence of our setup should be accentuated: the
radion of the traditional RS scenarios simply does not exist, so that our
Higgs-radion is not the conventional mixed state between the GW radion and the
Higgs.
| [
{
"created": "Wed, 11 Dec 2013 21:00:15 GMT",
"version": "v1"
},
{
"created": "Sun, 12 Jan 2014 20:11:54 GMT",
"version": "v2"
}
] | 2014-05-21 | [
[
"Geller",
"Michael",
""
],
[
"Bar-Shalom",
"Shaouly",
""
],
[
"Soni",
"Amarjit",
""
]
] | We investigate a Randall-Sundrum model with an SU(2) doublet propagating in the bulk. Upon calculating its gravitational effect we find that a stabilized radius can be generated without the use of an additional scalar, as needed for example in the Goldberger-Wise (GW) mechanism, and with no additional fine-tuning other than the inescapable one due to the cosmological constant; similar tuning is also present in the GW mechanism. The lowest scalar excitation in this scenario, the counterpart of the radion of the GW mechanism, has both radion-like and Higgs-like couplings to the SM fields. It, thus, plays a dual role and we, therefore, denote it as the "Higgs-radion" ($h_r$). As opposed to the GW radion case, our Higgs-radion is found to be compatible with the 126 GeV scalar recently discovered at the LHC, at the level of $1\sigma$, with a resulting $95\%$ CL bound on the KK-gluon mass of: $4.48~TeV<M_{KKG}< 5.44~TeV$. An important consequence of our setup should be accentuated: the radion of the traditional RS scenarios simply does not exist, so that our Higgs-radion is not the conventional mixed state between the GW radion and the Higgs. |
hep-ph/0108254 | Passarino Giampiero | G. Passarino (Turin Univ. and INFN Turin) | Are Constants Constant? | 10 pages(Latex) | null | null | null | hep-ph | null | The prospect of a time-dependent Higgs vacuum expectation value is examined
within the standard model of electroweak interactions. It is shown that the
classical equation of motion for the Higgs field admits a solution that is a
doubly-periodic function of time. The corresponding Dirac equation for the
electron field is equivalent to a second order differential equation with
doubly-periodic coefficients. In the limit of very large primitive period of
the Higgs background this equation can be solved in WKBJ approximation, showing
plane-wave solutions with a time-dependent distortion factor which can be made
arbitrarily small.
| [
{
"created": "Thu, 30 Aug 2001 15:36:32 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Passarino",
"G.",
"",
"Turin Univ. and INFN Turin"
]
] | The prospect of a time-dependent Higgs vacuum expectation value is examined within the standard model of electroweak interactions. It is shown that the classical equation of motion for the Higgs field admits a solution that is a doubly-periodic function of time. The corresponding Dirac equation for the electron field is equivalent to a second order differential equation with doubly-periodic coefficients. In the limit of very large primitive period of the Higgs background this equation can be solved in WKBJ approximation, showing plane-wave solutions with a time-dependent distortion factor which can be made arbitrarily small. |
hep-ph/0311213 | Dmitri Melikhov | D. Melikhov, O. Nachtmann, V. Nikonov, T. Paulus | Masses and couplings of vector mesons from the pion electromagnetic,
weak, and \pi\gamma transition form factors | revtex, 23 pages | Eur.Phys.J. C34 (2004) 345-360 | 10.1140/epjc/s2004-01726-4 | HD-THEP-03-58 (Uni Heidelberg) | hep-ph hep-ex | null | We analyse the pion electromagnetic, charged-current, and $\pi\gamma$
transition form factors at timelike momentum transfers $q$, $q^2=s\le 1.4$
GeV$^2$, using a dispersion approach. We discuss in detail the propagator
matrix of the photon-vector-meson system and define certain reduced amplitudes,
or vertex functions, describing the coupling of this system to final states. We
then apply the derived analytic expressions to the analysis of the recent
$e^+e^-\to \pi^+\pi^-$, $\tau^-\to \pi^-\pi^0\nu_\tau$, and $e^+e^-\to
\pi^0\gamma$ data. We find the reduced amplitudes for the coupling of the
photon and vector mesons to two pseudoscalars to be constant, independent of
$s$, in the range considered, indicating a "freezing" of the amplitudes for
$s\le 1$ GeV. The fit to the form factor data leads to the following values of
the Breit-Wigner resonance masses m_{\rho^-}=775.3\pm 0.8 MeV,
m_{\rho^0}=773.7\pm 0.6 MeV and m_\omega=782.43\pm 0.05 MeV, where the errors
are only statistical.
| [
{
"created": "Mon, 17 Nov 2003 17:21:44 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Melikhov",
"D.",
""
],
[
"Nachtmann",
"O.",
""
],
[
"Nikonov",
"V.",
""
],
[
"Paulus",
"T.",
""
]
] | We analyse the pion electromagnetic, charged-current, and $\pi\gamma$ transition form factors at timelike momentum transfers $q$, $q^2=s\le 1.4$ GeV$^2$, using a dispersion approach. We discuss in detail the propagator matrix of the photon-vector-meson system and define certain reduced amplitudes, or vertex functions, describing the coupling of this system to final states. We then apply the derived analytic expressions to the analysis of the recent $e^+e^-\to \pi^+\pi^-$, $\tau^-\to \pi^-\pi^0\nu_\tau$, and $e^+e^-\to \pi^0\gamma$ data. We find the reduced amplitudes for the coupling of the photon and vector mesons to two pseudoscalars to be constant, independent of $s$, in the range considered, indicating a "freezing" of the amplitudes for $s\le 1$ GeV. The fit to the form factor data leads to the following values of the Breit-Wigner resonance masses m_{\rho^-}=775.3\pm 0.8 MeV, m_{\rho^0}=773.7\pm 0.6 MeV and m_\omega=782.43\pm 0.05 MeV, where the errors are only statistical. |
hep-ph/0509173 | Luis. A. Sanchez | Simonetta Filippi, William A. Ponce, Luis A. Sanchez | Dark matter from the scalar sector of 3-3-1 models without exotic
electric charges | RevTeX, 11 pages. v2: typos corrected, one reference added. v3:
clarifications added, four more references added. To appear in Europhys. Lett | Europhys.Lett. 73 (2006) 142-148 | 10.1209/epl/i2005-10349-x | null | hep-ph | null | We show that three SU(2) singlet neutral scalars (two CP-even and one CP-odd)
in the spectrum of models based on the gauge symmetry SU(3)_c X SU(3)_L X
U(1)_X, which do not contain exotic electric charges, are realistic candidates
for thermally generated self-interacting dark matter in the Universe, a type of
dark matter that has been recently proposed in order to overcome some
difficulties of collisionless cold dark matter models at the galactic scale.
These candidates arise without introducing a new mass scale in the model and/or
without the need for a discrete symmetry to stabilize them, but at the expense
of tuning several combinations of parameters of the scalar potential.
| [
{
"created": "Fri, 16 Sep 2005 17:53:37 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Sep 2005 16:38:10 GMT",
"version": "v2"
},
{
"created": "Thu, 27 Oct 2005 18:47:25 GMT",
"version": "v3"
}
] | 2009-11-11 | [
[
"Filippi",
"Simonetta",
""
],
[
"Ponce",
"William A.",
""
],
[
"Sanchez",
"Luis A.",
""
]
] | We show that three SU(2) singlet neutral scalars (two CP-even and one CP-odd) in the spectrum of models based on the gauge symmetry SU(3)_c X SU(3)_L X U(1)_X, which do not contain exotic electric charges, are realistic candidates for thermally generated self-interacting dark matter in the Universe, a type of dark matter that has been recently proposed in order to overcome some difficulties of collisionless cold dark matter models at the galactic scale. These candidates arise without introducing a new mass scale in the model and/or without the need for a discrete symmetry to stabilize them, but at the expense of tuning several combinations of parameters of the scalar potential. |
1411.5575 | Wei Chao | Wei Chao | Electroweak Baryogenesis in the Exceptional Supersymmetric Standard
Model | 13 pages, 3 figures | null | 10.1088/1475-7516/2015/08/055 | ACFI-T14-21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study electroweak baryogenesis in the E_6 inspired exceptional
supersymmetric standard model ( E_6SSM ). The relaxation coefficients driven by
singlinos and the new gaugino as well as the transport equation of the Higgs
supermultiplet number density in the E_6SSM are calculated. Our numerical
simulation shows that both CP-violating source terms from singlinos and the new
gaugino can solely give rise to a correct baryon asymmetry of the Universe via
the electroweak baryogenesis mechanism.
| [
{
"created": "Thu, 20 Nov 2014 15:33:43 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Feb 2015 22:20:19 GMT",
"version": "v2"
}
] | 2015-09-16 | [
[
"Chao",
"Wei",
""
]
] | We study electroweak baryogenesis in the E_6 inspired exceptional supersymmetric standard model ( E_6SSM ). The relaxation coefficients driven by singlinos and the new gaugino as well as the transport equation of the Higgs supermultiplet number density in the E_6SSM are calculated. Our numerical simulation shows that both CP-violating source terms from singlinos and the new gaugino can solely give rise to a correct baryon asymmetry of the Universe via the electroweak baryogenesis mechanism. |
1002.3586 | Lorenzo Basso Mr | Lorenzo Basso, Alexander Belyaev, Stefano Moretti, Giovanni Marco
Pruna, Claire H. Shepherd-Themistocleous | $Z'$ discovery potential at the LHC in the minimal $B-L$ extension of
the Standard Model | 33 Pages, 14 figures and 8 tables. Updated Tevatron bounds and
comparison to CDF and D0; improved methodology explanation; commented on
inclusion of detector effects. Results changed only for the comparison to
Tevatron. Corrected typos and updated bibliography to match published version
in EPJC | Eur. Phys. J. C (2011) 71: 1613 | 10.1140/epjc/s10052-011-1613-6 | SHEP-09-19, DFTT 58/2009 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the Large Hadron Collider (LHC) discovery potential in the $Z'$
sector of a $U(1)_{B-L}$ enlarged Standard Model (that also includes three
heavy Majorana neutrinos and an additional Higgs boson) for $\sqrt{s}=7$, 10
and 14 TeV centre-of-mass (CM) energies, considering both the
$Z'_{B-L}\rightarrow e^+e^-$ and $Z'_{B-L}\rightarrow \mu^+\mu^-$ decay
channels. The comparison of the (irreducible) backgrounds with the expected
backgrounds for the D$\O$ experiment at the Tevatron validates our simulation.
We propose an alternative analysis that has the potential to improve the D$\O$
sensitivity. Electrons provide a higher sensitivity to smaller couplings at
small $Z'_{B-L}$ boson masses than do muons. The resolutions achievable may
allow the $Z'_{B-L}$ boson width to be measured at smaller masses in the case
of electrons in the final state. The run of the LHC at $\sqrt{s}=7$ TeV,
assuming at most $\int \mathcal{L} \sim 1$ fb$^{-1}$, will be able to give
similar results to those that will be available soon at the Tevatron in the
lower mass region, and to extend them for a heavier $M_{Z'}$.
| [
{
"created": "Thu, 18 Feb 2010 19:31:48 GMT",
"version": "v1"
},
{
"created": "Sat, 25 Sep 2010 09:41:31 GMT",
"version": "v2"
},
{
"created": "Tue, 5 Apr 2011 11:00:03 GMT",
"version": "v3"
}
] | 2011-04-13 | [
[
"Basso",
"Lorenzo",
""
],
[
"Belyaev",
"Alexander",
""
],
[
"Moretti",
"Stefano",
""
],
[
"Pruna",
"Giovanni Marco",
""
],
[
"Shepherd-Themistocleous",
"Claire H.",
""
]
] | We present the Large Hadron Collider (LHC) discovery potential in the $Z'$ sector of a $U(1)_{B-L}$ enlarged Standard Model (that also includes three heavy Majorana neutrinos and an additional Higgs boson) for $\sqrt{s}=7$, 10 and 14 TeV centre-of-mass (CM) energies, considering both the $Z'_{B-L}\rightarrow e^+e^-$ and $Z'_{B-L}\rightarrow \mu^+\mu^-$ decay channels. The comparison of the (irreducible) backgrounds with the expected backgrounds for the D$\O$ experiment at the Tevatron validates our simulation. We propose an alternative analysis that has the potential to improve the D$\O$ sensitivity. Electrons provide a higher sensitivity to smaller couplings at small $Z'_{B-L}$ boson masses than do muons. The resolutions achievable may allow the $Z'_{B-L}$ boson width to be measured at smaller masses in the case of electrons in the final state. The run of the LHC at $\sqrt{s}=7$ TeV, assuming at most $\int \mathcal{L} \sim 1$ fb$^{-1}$, will be able to give similar results to those that will be available soon at the Tevatron in the lower mass region, and to extend them for a heavier $M_{Z'}$. |
2206.11742 | Tianbo Liu | Jing Zhao, Zhe Zhang, Zuo-tang Liang, Tianbo Liu, Ya-jin Zhou | Inclusive and semi-inclusive production of spin-3/2 hadrons in $e^+e^-$
annihilation | 42 pages, 4 figures, matching the published version in Physical
Review D | Phys. Rev. D 106, 094006 (2022) | 10.1103/PhysRevD.106.094006 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We investigate the inclusive and semi-inclusive productions of spin-3/2
hadrons, such as $\Omega$, in unpolarized $e^+ e^-$ annihilation. The general
differential cross sections are expressed in terms of structure functions in
accordance to the polarization of the hadron and the azimuthal modulations. We
derive a complete definition of quark transverse momentum dependent (TMD)
fragmentation functions (FFs) to spin-3/2 hadrons for the first time from the
decomposition of the quark-quark correlation matrix at leading twist, 14 of
which are newly defined corresponding to rank-3 tensor polarized hadron. The
collinear FFs are obtained from the $k_T$-integrated correlation matrix, and
only two TMD FFs with rank-3 tensor polarization have nonvanishing collinear
counterparts. Then we perform a leading order calculation of the unpolarized
differential cross sections. In the single-hadron inclusive production, only
two structure functions are found nonzero and none of the rank-3 tensor
polarized FFs contributes. For the nearly back-to-back two-hadron production,
half of the 48 structure functions are found nonzero even if the spin of the
second hadron is not analyzed, and ten of the rank-3 tensor polarized TMD FFs
contribute. Therefore, one can study the rank-3 tensor polarized FFs via the
production of a spin-3/2 hadron and an unpolarized hadron in unpolarized $e^+
e^-$ collision experiments. These newly defined FFs can be further applied in
semi-inclusive deep inelastic scattering processes for the study of nucleon
structures.
| [
{
"created": "Thu, 23 Jun 2022 14:39:13 GMT",
"version": "v1"
},
{
"created": "Tue, 8 Nov 2022 04:56:37 GMT",
"version": "v2"
}
] | 2022-11-09 | [
[
"Zhao",
"Jing",
""
],
[
"Zhang",
"Zhe",
""
],
[
"Liang",
"Zuo-tang",
""
],
[
"Liu",
"Tianbo",
""
],
[
"Zhou",
"Ya-jin",
""
]
] | We investigate the inclusive and semi-inclusive productions of spin-3/2 hadrons, such as $\Omega$, in unpolarized $e^+ e^-$ annihilation. The general differential cross sections are expressed in terms of structure functions in accordance to the polarization of the hadron and the azimuthal modulations. We derive a complete definition of quark transverse momentum dependent (TMD) fragmentation functions (FFs) to spin-3/2 hadrons for the first time from the decomposition of the quark-quark correlation matrix at leading twist, 14 of which are newly defined corresponding to rank-3 tensor polarized hadron. The collinear FFs are obtained from the $k_T$-integrated correlation matrix, and only two TMD FFs with rank-3 tensor polarization have nonvanishing collinear counterparts. Then we perform a leading order calculation of the unpolarized differential cross sections. In the single-hadron inclusive production, only two structure functions are found nonzero and none of the rank-3 tensor polarized FFs contributes. For the nearly back-to-back two-hadron production, half of the 48 structure functions are found nonzero even if the spin of the second hadron is not analyzed, and ten of the rank-3 tensor polarized TMD FFs contribute. Therefore, one can study the rank-3 tensor polarized FFs via the production of a spin-3/2 hadron and an unpolarized hadron in unpolarized $e^+ e^-$ collision experiments. These newly defined FFs can be further applied in semi-inclusive deep inelastic scattering processes for the study of nucleon structures. |
hep-ph/9711210 | null | Giancarlo D'Ambrosio and Jorge Portoles, (INFN, Naples) | Analysis of K_L -> pi^+ pi^- gamma in Chiral Perturbation Theory | 39 pages, plain LaTeX file, uses epsf, 7 figures included as PS
files. Minor correction in the O(p^6) loop calculation. Results essentially
unchanged. Version accepted for publication in Nuclear Physics B | Nucl.Phys. B533 (1998) 523-554 | 10.1016/S0550-3213(98)00481-7 | INFNNA-IV-97/26, DSFNA-IV-97/26 | hep-ph hep-ex | null | We study the long-distance dominated K_L -> pi^+ pi^- gamma decay at O(p^6)
in Chiral Perturbation Theory. The complete calculation of the O(p^6) loop
magnetic amplitude is carried out. At this chiral order the model dependent
part of the vector meson exchange contribution to the magnetic amplitude is
evaluated in the two models : FM (Factorization Model) and FMV (Factorization
Model in the Vector Couplings). We predict, in an almost model independent way,
a slope of K_L -> pi^+ pi^- gamma in the range c = -1.6,-1.8, consistently with
the experimental value. We find that the experimental result for the width of
K_L -> pi^+ pi^- gamma is compatible with a bigger breaking of the nonet
symmetry in the weak vertices than previously stated. Thus we conclude that our
analysis does not exclude an opposite sign to the one given by the dominance of
the pion pole in the poorly known K_L -> gamma gamma amplitude. A complete
analysis of the O(p^3) weak Vector-Pseudoscalar-Pseudoscalar (VPP) vertex is
also performed.
| [
{
"created": "Mon, 3 Nov 1997 14:47:30 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Jun 1998 08:50:04 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"D'Ambrosio",
"Giancarlo",
""
],
[
"Portoles",
"Jorge",
""
]
] | We study the long-distance dominated K_L -> pi^+ pi^- gamma decay at O(p^6) in Chiral Perturbation Theory. The complete calculation of the O(p^6) loop magnetic amplitude is carried out. At this chiral order the model dependent part of the vector meson exchange contribution to the magnetic amplitude is evaluated in the two models : FM (Factorization Model) and FMV (Factorization Model in the Vector Couplings). We predict, in an almost model independent way, a slope of K_L -> pi^+ pi^- gamma in the range c = -1.6,-1.8, consistently with the experimental value. We find that the experimental result for the width of K_L -> pi^+ pi^- gamma is compatible with a bigger breaking of the nonet symmetry in the weak vertices than previously stated. Thus we conclude that our analysis does not exclude an opposite sign to the one given by the dominance of the pion pole in the poorly known K_L -> gamma gamma amplitude. A complete analysis of the O(p^3) weak Vector-Pseudoscalar-Pseudoscalar (VPP) vertex is also performed. |
hep-ph/9210281 | null | G.P.Korchemsky and G.Marchesini | Structure functions for large $x$ and renormalization of Wilson loops | 27 pages, LaTeX style; typos fixed, results for two-loop anomalous
dimensions corrected, a note added | Nucl.Phys.B406:225-258,1993 | 10.1016/0550-3213(93)90167-N | UPRF-92-354 | hep-ph | null | We discuss the relation between partonic distributions near the phase space
boundary and Wilson loop expectation values calculated along paths partially
lying on the light-cone. Due to additional light-cone singularities,
multiplicative renormalizability for these expectation values is lost.
Nevertheless we establish the renormalization group equation for the light like
Wilson loops and show that it is equivalent to the evolution equation for the
physical distributions. By performing a two-loop calculation we verify these
properties and show that the universal form of the splitting function for large
x originates from the cusp anomalous dimension of Wilson loops.
| [
{
"created": "Fri, 30 Oct 1992 16:55:00 GMT",
"version": "v1"
},
{
"created": "Fri, 4 Feb 2005 13:02:31 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Korchemsky",
"G. P.",
""
],
[
"Marchesini",
"G.",
""
]
] | We discuss the relation between partonic distributions near the phase space boundary and Wilson loop expectation values calculated along paths partially lying on the light-cone. Due to additional light-cone singularities, multiplicative renormalizability for these expectation values is lost. Nevertheless we establish the renormalization group equation for the light like Wilson loops and show that it is equivalent to the evolution equation for the physical distributions. By performing a two-loop calculation we verify these properties and show that the universal form of the splitting function for large x originates from the cusp anomalous dimension of Wilson loops. |
0906.3555 | M.I. Vyazovsky | M.A.Braun, M.Yu.Salykin and M.I.Vyazovsky (Saint-Petersburg State
University, Russia) | Production of two gluons in the Lipatov effective action formalism | 15 pages, 3 figures; published in Eur.Phys.J. C | Eur.Phys.J.C65:385-394,2010 | 10.1140/epjc/s10052-009-1184-y | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The one-loop diffractive amplitude for emission of two real gluons with
widely different rapidities is studied in the Lipatov effective action
formalism. It is shown that after integration over longitudinal momenta in the
loop the resulting expression coincides with the one obtained by the
Lipatov-Bartels formalism in transversal space provided the same prescription
is used to exclude divergent contributions as previously proposed for emission
of a single real gluon.
| [
{
"created": "Fri, 19 Jun 2009 00:12:55 GMT",
"version": "v1"
},
{
"created": "Fri, 5 Feb 2010 01:20:13 GMT",
"version": "v2"
}
] | 2010-02-11 | [
[
"Braun",
"M. A.",
"",
"Saint-Petersburg State\n University, Russia"
],
[
"Salykin",
"M. Yu.",
"",
"Saint-Petersburg State\n University, Russia"
],
[
"Vyazovsky",
"M. I.",
"",
"Saint-Petersburg State\n University, Russia"
]
] | The one-loop diffractive amplitude for emission of two real gluons with widely different rapidities is studied in the Lipatov effective action formalism. It is shown that after integration over longitudinal momenta in the loop the resulting expression coincides with the one obtained by the Lipatov-Bartels formalism in transversal space provided the same prescription is used to exclude divergent contributions as previously proposed for emission of a single real gluon. |
0806.0890 | Michael Chanowitz | Michael S. Chanowitz | A Z' Boson and the Higgs Boson Mass | 36 Pages, 15 figures, v2: added CDF constraints and references | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Standard Model fit prefers values of the Higgs boson mass that are below
the 114 GeV direct lower limit from LEP II. The discrepancy is acute if the 3.2
sigma disagreement for the effective weak interaction mixing angle from the two
most precise measurements is attributed to underestimated systematic error. In
that case the data suggests new physics to raise the predicted value of the
Higgs mass. One of the simplest possibilities is a Z' boson, which would
generically increase the prediction for the Higgs mass as a result of Z-Z'
mixing. We explore the effect of Z-Z' mixing on the Higgs mass prediction,
using both the full data set and the reduced data set that omits the hadronic
asymmetry measurements of the weak mixing angle, which are more likely than the
leptonic asymmetry measurements to have underestimated systematic uncertainty.
| [
{
"created": "Thu, 5 Jun 2008 03:06:26 GMT",
"version": "v1"
},
{
"created": "Wed, 25 Jun 2008 21:29:39 GMT",
"version": "v2"
}
] | 2008-06-26 | [
[
"Chanowitz",
"Michael S.",
""
]
] | The Standard Model fit prefers values of the Higgs boson mass that are below the 114 GeV direct lower limit from LEP II. The discrepancy is acute if the 3.2 sigma disagreement for the effective weak interaction mixing angle from the two most precise measurements is attributed to underestimated systematic error. In that case the data suggests new physics to raise the predicted value of the Higgs mass. One of the simplest possibilities is a Z' boson, which would generically increase the prediction for the Higgs mass as a result of Z-Z' mixing. We explore the effect of Z-Z' mixing on the Higgs mass prediction, using both the full data set and the reduced data set that omits the hadronic asymmetry measurements of the weak mixing angle, which are more likely than the leptonic asymmetry measurements to have underestimated systematic uncertainty. |
hep-ph/9711287 | FJ Yndurain | A. Pineda and F. J. Yndurain | Calculation of Quarkonium Spectrum and $m_b, m_c$ to Order $\alpha_s^4$ | Plain TeX file | Phys.Rev.D58:094022,1998 | 10.1103/PhysRevD.58.094022 | UB-ECM-PF 97/34 and FTUAM 97-15 | hep-ph | null | We include two loop, relativistic one loop and second order relativistic tree
level corrections, plus leading nonperturbative contributions, to obtain a
calculation of the lower states in the heavy quarkonium spectrum correct up to,
and including, $O(\alpha_s^4)$ and leading $\Lambda^4/m^4$ terms. This allows
us, in particular, to obtain a model independent determination of the pole
masses of the $b, c$ quarks, $$m_b=5 015^{+110}_{-70} mev; m_c=1
884^{+222}_{-133} mev$$ to which correspond the $\bar{\hbox{MS}}$ masses,
$$\bar{m}_b(\bar{m}_b^2)=4 453^{+50}_{-32} mev; \bar{m}_c(\bar{m}_c^2)=1
547^{+169}_{-102} mev.$$ The decay $\Gamma(\Upsilon\to e^+e^-)$ is found in
agreement with experiment, $$\Gamma(\Upsilon\to e^+e^-)=1.135^{+0.27}_{-0.29}
kev (\hbox{exp.}=1.320\pm0.04 kev),$$ and the hyperfine splitting is predicted
to be $$M(\Upsilon)-M(\eta)=48.5^{+15.7}_{-12.2} mev.$$
| [
{
"created": "Tue, 11 Nov 1997 12:30:25 GMT",
"version": "v1"
}
] | 2011-01-27 | [
[
"Pineda",
"A.",
""
],
[
"Yndurain",
"F. J.",
""
]
] | We include two loop, relativistic one loop and second order relativistic tree level corrections, plus leading nonperturbative contributions, to obtain a calculation of the lower states in the heavy quarkonium spectrum correct up to, and including, $O(\alpha_s^4)$ and leading $\Lambda^4/m^4$ terms. This allows us, in particular, to obtain a model independent determination of the pole masses of the $b, c$ quarks, $$m_b=5 015^{+110}_{-70} mev; m_c=1 884^{+222}_{-133} mev$$ to which correspond the $\bar{\hbox{MS}}$ masses, $$\bar{m}_b(\bar{m}_b^2)=4 453^{+50}_{-32} mev; \bar{m}_c(\bar{m}_c^2)=1 547^{+169}_{-102} mev.$$ The decay $\Gamma(\Upsilon\to e^+e^-)$ is found in agreement with experiment, $$\Gamma(\Upsilon\to e^+e^-)=1.135^{+0.27}_{-0.29} kev (\hbox{exp.}=1.320\pm0.04 kev),$$ and the hyperfine splitting is predicted to be $$M(\Upsilon)-M(\eta)=48.5^{+15.7}_{-12.2} mev.$$ |
hep-ph/0312391 | Pedro Bicudo | P. Bicudo, G. M. Marques | The Theta+ (1540) as an overlap of a pion, a kaon and a nucleon | 5 pages, 3 figures, 1 table, contribution to the X International
Conference on Hadron Spectroscopy, HADRON 2003, August 31 - September 6,
2003, Aschaffenburg, Germany | AIP Conf.Proc. 717 (2004) 467-474 | 10.1063/1.1799751 | null | hep-ph | null | We study the very recently discovered $\Theta^+$ (1540) at SPring-8, at ITEP
and at CLAS-Thomas Jefferson Lab. We apply the same RGM techniques that already
explained with success the repulsive hard core of nucleon-nucleon, kaon-nucleon
exotic scattering, and the attractive hard core present in pion-nucleon and
pion-pion non-exotic scattering. We find that the K-N repulsion excludes the
Theta+ as a K-N s-wave pentaquark. We explore the Theta+ as heptaquark,
equivalent to a N+pi+K borromean boundstate, with positive parity and total
isospin I=0. We find that the kaon-nucleon repulsion is cancelled by the
attraction existing both in the pion-nucleon and pion-kaon channels. Although
we are not yet able to bind the total three body system, we find that the
Theta+ may still be a heptaquark state.
| [
{
"created": "Wed, 31 Dec 2003 19:43:19 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Bicudo",
"P.",
""
],
[
"Marques",
"G. M.",
""
]
] | We study the very recently discovered $\Theta^+$ (1540) at SPring-8, at ITEP and at CLAS-Thomas Jefferson Lab. We apply the same RGM techniques that already explained with success the repulsive hard core of nucleon-nucleon, kaon-nucleon exotic scattering, and the attractive hard core present in pion-nucleon and pion-pion non-exotic scattering. We find that the K-N repulsion excludes the Theta+ as a K-N s-wave pentaquark. We explore the Theta+ as heptaquark, equivalent to a N+pi+K borromean boundstate, with positive parity and total isospin I=0. We find that the kaon-nucleon repulsion is cancelled by the attraction existing both in the pion-nucleon and pion-kaon channels. Although we are not yet able to bind the total three body system, we find that the Theta+ may still be a heptaquark state. |
hep-ph/0104079 | J. C. Yoon | J.C. Yoon | Theoretical correction to the neutral $B^0$ meson asymmetry | 7 pages | Mod.Phys.Lett. A21 (2006) 985-989 | 10.1142/S0217732306020354 | null | hep-ph | null | Certain types of asymmetries in neutral meson physics have not been treated
properly, ignoring the difference of normalization factors with an assumption
of the equality of total decay width. Since the corrected asymmetries in $B^0$
meson are different from known asymmetries by a shift in the first order of CP-
and CPT-violation parameters, experimental data should be analyzed with the
consideration of this effect as in $K^0$ meson physics.
| [
{
"created": "Sun, 8 Apr 2001 23:37:01 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Apr 2001 13:03:42 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Yoon",
"J. C.",
""
]
] | Certain types of asymmetries in neutral meson physics have not been treated properly, ignoring the difference of normalization factors with an assumption of the equality of total decay width. Since the corrected asymmetries in $B^0$ meson are different from known asymmetries by a shift in the first order of CP- and CPT-violation parameters, experimental data should be analyzed with the consideration of this effect as in $K^0$ meson physics. |
2303.15173 | Liang Tang | Yi-Cheng Zhao, Chun-Meng Tang, and Liang Tang | Mass predictions of triply heavy hybrid baryons via QCD sum rules | 20 pages, 4 figures, 2 tables. To match the published version | null | 10.1140/epjc/s10052-023-11825-z | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | In this article, we study the mass spectrum of the low-lying triply heavy
hybrid baryon, which consists of three valence heavy quarks in a color octet
and one valence gluon, with spin-parity $J^P=(\frac{1}{2})^+$ via QCD sum
rules. This is the first study on the triply heavy hybrid baryons in the
framework of QCD sum rules. After performing the QCD sum rule analysis, we find
that the mass of $cccg$ hybrid baryon lies in $M_{cccg}= 5.91-6.13$ GeV. As a
byproduct, the mass of the triply bottom hybrid baryon state is extracted to be
around $M_{bbbg}=14.62-14.82$ GeV. The contributions up to dimension eight at
the leading order of $\alpha_s$ (LO) in the operator product expansion are
taken into account in the calculation. The triply charmed hybrid baryon
predicted in this work can decay into one doubly charmed baryon and one charmed
meson. Especially, we propose to search for $cccg$ hybrid baryon with $J^{P}=
(1/2)^+$ in the P-wave decay channels $\Xi_{cc}^{++} D^0$, $\Xi_{cc}^{+} D^+$,
and $\Xi_{ccs}^{+} D_s^+$, which may be accessible in future BelleII, Super-B,
PANDA, and LHCb experiments.
| [
{
"created": "Mon, 27 Mar 2023 13:03:10 GMT",
"version": "v1"
},
{
"created": "Sat, 19 Aug 2023 23:34:12 GMT",
"version": "v2"
}
] | 2023-08-22 | [
[
"Zhao",
"Yi-Cheng",
""
],
[
"Tang",
"Chun-Meng",
""
],
[
"Tang",
"Liang",
""
]
] | In this article, we study the mass spectrum of the low-lying triply heavy hybrid baryon, which consists of three valence heavy quarks in a color octet and one valence gluon, with spin-parity $J^P=(\frac{1}{2})^+$ via QCD sum rules. This is the first study on the triply heavy hybrid baryons in the framework of QCD sum rules. After performing the QCD sum rule analysis, we find that the mass of $cccg$ hybrid baryon lies in $M_{cccg}= 5.91-6.13$ GeV. As a byproduct, the mass of the triply bottom hybrid baryon state is extracted to be around $M_{bbbg}=14.62-14.82$ GeV. The contributions up to dimension eight at the leading order of $\alpha_s$ (LO) in the operator product expansion are taken into account in the calculation. The triply charmed hybrid baryon predicted in this work can decay into one doubly charmed baryon and one charmed meson. Especially, we propose to search for $cccg$ hybrid baryon with $J^{P}= (1/2)^+$ in the P-wave decay channels $\Xi_{cc}^{++} D^0$, $\Xi_{cc}^{+} D^+$, and $\Xi_{ccs}^{+} D_s^+$, which may be accessible in future BelleII, Super-B, PANDA, and LHCb experiments. |
2405.19774 | Ken-Ichi Hikasa | Ken-ichi Hikasa | CPT, Majorana fermions, and particle physics beyond the Standard Model | 12 pages | null | null | TU-1235 | hep-ph hep-th | http://creativecommons.org/licenses/by-nc-nd/4.0/ | After reviewing charge conjugation and the CPT theorem, we define Majorana
fermions and clarify the relationship of Majorana, Weyl, and Dirac fields.
Appearance of Majorana fermions in various scenarios of physics beyond the
Standard Model is discussed, including neutrino masses, baryon asymmetry of the
universe, grand unified theories, and supersymmetry.
| [
{
"created": "Thu, 30 May 2024 07:39:50 GMT",
"version": "v1"
}
] | 2024-05-31 | [
[
"Hikasa",
"Ken-ichi",
""
]
] | After reviewing charge conjugation and the CPT theorem, we define Majorana fermions and clarify the relationship of Majorana, Weyl, and Dirac fields. Appearance of Majorana fermions in various scenarios of physics beyond the Standard Model is discussed, including neutrino masses, baryon asymmetry of the universe, grand unified theories, and supersymmetry. |
hep-ph/0001300 | Gorbunov | D. S. Gorbunov | On Electroweak Baryogenesis in Gauge Mediated Models with
Messenger-Matter Mixing | 12 pages | Mod.Phys.Lett.A15:207-217,2000 | 10.1016/S0217-7323(00)00020-7 | null | hep-ph | null | We consider feasibility of electroweak baryogenesis in gauge mediated
supersymmetry breaking models with messenger-matter mixing. We present a class
of models where electroweak baryogenesis produces sufficient amount of baryon
asymmetry. The main features of these models are ({\it i}) large mixing between
messengers and right stop and ({\it ii}) fairly narrow region of viable
$\tan\beta$.
| [
{
"created": "Fri, 28 Jan 2000 17:59:44 GMT",
"version": "v1"
}
] | 2011-07-19 | [
[
"Gorbunov",
"D. S.",
""
]
] | We consider feasibility of electroweak baryogenesis in gauge mediated supersymmetry breaking models with messenger-matter mixing. We present a class of models where electroweak baryogenesis produces sufficient amount of baryon asymmetry. The main features of these models are ({\it i}) large mixing between messengers and right stop and ({\it ii}) fairly narrow region of viable $\tan\beta$. |
hep-ph/9705291 | Lech Szymanowski | R. Kirschner and L. Szymanowski | Gluonic reggeons | 18 pages, LATEX, 2 EPS figures, revised, to be published in Phys.
Lett. B | Phys.Lett.B419:348-356,1998 | 10.1016/S0370-2693(97)01283-5 | NTZ 15/97 | hep-ph | null | Contributions from gluon interactions, which are non-leading in high-energy
semi-hard processes, are studied and represented in terms of reggeon exchanges.
Unlike the leading gluonic reggeon, related to the BFKL pomeron, the
non-leading reggeons are sensitive to the spin and transverse momentum
distributions of scattering partons. There are several gluonic reggeons with
poles in the vicinity of angular momentum $j=0$ contributing to the
perturbative Regge asymptotics of QCD. We extend the high-energy effective
action including sub-leading terms which describe these reggeons and their
interactions with scattering quarks and gluons in the multi-Regge
approximation.
| [
{
"created": "Mon, 12 May 1997 07:15:43 GMT",
"version": "v1"
},
{
"created": "Tue, 14 Oct 1997 11:37:17 GMT",
"version": "v2"
},
{
"created": "Wed, 15 Oct 1997 11:13:04 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Kirschner",
"R.",
""
],
[
"Szymanowski",
"L.",
""
]
] | Contributions from gluon interactions, which are non-leading in high-energy semi-hard processes, are studied and represented in terms of reggeon exchanges. Unlike the leading gluonic reggeon, related to the BFKL pomeron, the non-leading reggeons are sensitive to the spin and transverse momentum distributions of scattering partons. There are several gluonic reggeons with poles in the vicinity of angular momentum $j=0$ contributing to the perturbative Regge asymptotics of QCD. We extend the high-energy effective action including sub-leading terms which describe these reggeons and their interactions with scattering quarks and gluons in the multi-Regge approximation. |
2109.06089 | Le Tho Hue | L. T. Hue, Khiem Hong Phan, T. Phong Nguyen, H. N. Long, H. T. Hung | An explanation of experimental data of $(g-2)_{e,\mu}$ in 3-3-1 models
with inverse seesaw neutrinos | 43 pages,6 Figures. Numerical results and typos are corrected. New
references are added | Eur. Phys. J. C 82 (2022) 722 | 10.1140/epjc/s10052-022-10691-5 | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | We show that the anomalous magnetic moment experimental data of muon and
electron $(g-2)_{\mu,e}$ can be explained simultaneously in simple extensions
of the 3-3-1 models consisting of new heavy neutrinos and a singly charged
Higgs boson. The heavy neutrinos generate active neutrino masses and mixing
through the general seesaw mechanism. They also have non-zero Yukawa couplings
with singly charged Higgs bosons and right-handed charged leptons, which result
in large one-loop contributions known as \emph{chirally-enhanced} ones.
Numerical investigation confirms a conclusion indicated previously that these
contributions are the key point to explain the large $(g-2)_{\mu,e}$ data,
provided that the inverse seesaw mechanism is necessary to allow both
conditions that heavy neutrino masses are above few hundred GeV and non-unitary
part of the active neutrino mixing matrix must be large enough.
| [
{
"created": "Mon, 13 Sep 2021 16:07:09 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Aug 2022 06:29:54 GMT",
"version": "v2"
}
] | 2022-08-23 | [
[
"Hue",
"L. T.",
""
],
[
"Phan",
"Khiem Hong",
""
],
[
"Nguyen",
"T. Phong",
""
],
[
"Long",
"H. N.",
""
],
[
"Hung",
"H. T.",
""
]
] | We show that the anomalous magnetic moment experimental data of muon and electron $(g-2)_{\mu,e}$ can be explained simultaneously in simple extensions of the 3-3-1 models consisting of new heavy neutrinos and a singly charged Higgs boson. The heavy neutrinos generate active neutrino masses and mixing through the general seesaw mechanism. They also have non-zero Yukawa couplings with singly charged Higgs bosons and right-handed charged leptons, which result in large one-loop contributions known as \emph{chirally-enhanced} ones. Numerical investigation confirms a conclusion indicated previously that these contributions are the key point to explain the large $(g-2)_{\mu,e}$ data, provided that the inverse seesaw mechanism is necessary to allow both conditions that heavy neutrino masses are above few hundred GeV and non-unitary part of the active neutrino mixing matrix must be large enough. |
1004.4789 | C. Hanhart | A. A. Filin, A. Romanov, V. Baru, C. Hanhart, Yu. S. Kalashnikova, A.
E. Kudryavtsev, U.-G. Mei{\ss}ner, A. V. Nefediev | Comment on "Possibility of Deeply Bound Hadronic Molecules from Single
Pion Exchange" | one page, one figure | Phys.Rev.Lett.105:019101,2010 | 10.1103/PhysRevLett.105.019101 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We demonstrate that in calculation, where unitarity constraints are properly
imposed, the deeply bound hadronic molecules recently proposed by Close and
Downum do not exist.
| [
{
"created": "Tue, 27 Apr 2010 12:55:24 GMT",
"version": "v1"
}
] | 2016-08-14 | [
[
"Filin",
"A. A.",
""
],
[
"Romanov",
"A.",
""
],
[
"Baru",
"V.",
""
],
[
"Hanhart",
"C.",
""
],
[
"Kalashnikova",
"Yu. S.",
""
],
[
"Kudryavtsev",
"A. E.",
""
],
[
"Meißner",
"U. -G.",
""
],
[
"Nefe... | We demonstrate that in calculation, where unitarity constraints are properly imposed, the deeply bound hadronic molecules recently proposed by Close and Downum do not exist. |
1507.06787 | Pedro Fern\'andez | P. Fernandez Soler, Zhi-Feng Sun, J. Nieves and E. Oset | The $\rho(\omega)B^*(B)$ interaction and states of $J=0,1,2$ | null | Eur. Phys. J. C 76 no. 2, 82 (2016) | 10.1140/epjc/s10052-016-3918-y | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we study systems composed of a $\rho/\omega$ and $B^*$ meson
pair. We find three bound states in isospin, spin-parity channels $(1/2, 0^+)$,
$(1/2, 1^+)$ and $(1/2, 2^+)$. The state with $J=2$ can be a good candidate for
the $B_2^*(5747)$. We also study the $\rho B$ system, and a bound state with
mass $5728$ MeV and width around $20$ MeV is obtained, which can be identified
with the $B_1(5721)$ resonance. In the case of $I=3/2$, one obtains repulsion
and thus, no exotic (molecular) mesons in this sector are generated in the
approach.
| [
{
"created": "Fri, 24 Jul 2015 08:59:24 GMT",
"version": "v1"
}
] | 2016-11-21 | [
[
"Soler",
"P. Fernandez",
""
],
[
"Sun",
"Zhi-Feng",
""
],
[
"Nieves",
"J.",
""
],
[
"Oset",
"E.",
""
]
] | In this work, we study systems composed of a $\rho/\omega$ and $B^*$ meson pair. We find three bound states in isospin, spin-parity channels $(1/2, 0^+)$, $(1/2, 1^+)$ and $(1/2, 2^+)$. The state with $J=2$ can be a good candidate for the $B_2^*(5747)$. We also study the $\rho B$ system, and a bound state with mass $5728$ MeV and width around $20$ MeV is obtained, which can be identified with the $B_1(5721)$ resonance. In the case of $I=3/2$, one obtains repulsion and thus, no exotic (molecular) mesons in this sector are generated in the approach. |
2007.08258 | Kai Gallmeister | Kai Gallmeister and Carsten Greiner (Goethe University, Frankfurt am
Main) | Production of Light Nuclei in Heavy Ion Collisions via Hagedorn
Resonances | 7 pages, 6 figures | null | 10.1140/epja/s10050-020-00329-z | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The physical processes behind the production of light nuclei in heavy ion
collisions are unclear. The nice theoretical description of experimental yields
by thermal models conflicts with the very small binding energies of the
observed states, being fragile in such a hot and dense environment. Other
available ideas are delayed production via coalescence, or a cooling of the
system after the chemical freeze-out according a Saha equation, or a `quench'
instead of a thermal freeze-out. A recently derived prescription of an
(interacting) Hagedorn gas is applied to consolidate the above pictures. The
tabulation of decay rates of Hagedorn states into light nuclei allows to
calculate yields usually unaccessable due to very poor Monte Carlo statistics.
Decay yields of stable hadrons and light nuclei are calculated. While the
scale-free decays of Hagedorn states alone are not compatible with the
experimental data, a thermalized hadron and Hagedorn state gas is able to
describe the experimental data. Applying a cooling of the system according a
Saha-equation with conservation of nucleons and anti-nucleons in number leads
to (nearly) temperature independent yields, thus a production of the light
nuclei at temperatures much lower than the chemical freeze-out temperature is
possible.
| [
{
"created": "Thu, 16 Jul 2020 11:08:50 GMT",
"version": "v1"
}
] | 2021-03-17 | [
[
"Gallmeister",
"Kai",
"",
"Goethe University, Frankfurt am\n Main"
],
[
"Greiner",
"Carsten",
"",
"Goethe University, Frankfurt am\n Main"
]
] | The physical processes behind the production of light nuclei in heavy ion collisions are unclear. The nice theoretical description of experimental yields by thermal models conflicts with the very small binding energies of the observed states, being fragile in such a hot and dense environment. Other available ideas are delayed production via coalescence, or a cooling of the system after the chemical freeze-out according a Saha equation, or a `quench' instead of a thermal freeze-out. A recently derived prescription of an (interacting) Hagedorn gas is applied to consolidate the above pictures. The tabulation of decay rates of Hagedorn states into light nuclei allows to calculate yields usually unaccessable due to very poor Monte Carlo statistics. Decay yields of stable hadrons and light nuclei are calculated. While the scale-free decays of Hagedorn states alone are not compatible with the experimental data, a thermalized hadron and Hagedorn state gas is able to describe the experimental data. Applying a cooling of the system according a Saha-equation with conservation of nucleons and anti-nucleons in number leads to (nearly) temperature independent yields, thus a production of the light nuclei at temperatures much lower than the chemical freeze-out temperature is possible. |
hep-ph/0511068 | Masataka Fukugita | Masataka Fukugita | Massive Neutrinos in Cosmology | Plenary talk given at NuFact05, Frascati, 21-26 June 2005 | Nucl.Phys.Proc.Suppl.155:10-17,2006 | 10.1016/j.nuclphysbps.2006.02.002 | null | hep-ph | null | The roles of massive neutrinos in cosmology -- in leptogenesis and in the
evolution of mass density fluctuations -- are reviewed. Emphasis is given to
the limit on neutrino mass from these considerations.
| [
{
"created": "Mon, 7 Nov 2005 09:41:55 GMT",
"version": "v1"
}
] | 2009-05-11 | [
[
"Fukugita",
"Masataka",
""
]
] | The roles of massive neutrinos in cosmology -- in leptogenesis and in the evolution of mass density fluctuations -- are reviewed. Emphasis is given to the limit on neutrino mass from these considerations. |
hep-ph/9610414 | Sarantsev Andrei | V.V. Anisovich, Yu.D. Prokoshkin, A.V. Sarantsev | Nonet Classification of Scalar/Isoscalar Resonances below 1900 MeV: the
Existence of an Extra Scalar State in the Region 1200-1600 MeV | LaTex 26 pages and 8 figures | Phys.Lett. B389 (1996) 388-396 | 10.1016/S0370-2693(96)01317-2 | null | hep-ph | null | A classification of the $IJ^{PC}=00^{++}$ mesons is performed on the basis of
the K-matrix analysis of meson spectra in the reactions: (i) GAMS data on $\pi
p\to \pi^0\pi^0 n$, $\eta\eta n$, $\eta\eta' n$; (ii) Crystal Barrel data on
$p\bar p~(at~rest)\to \pi^0\pi^0\pi^0$, $\pi^0\pi^0\eta$, $\pi^0\eta\eta$;
(iii) CERN-M\"unich data on $\pi p\to \pi^+\pi^- n$; (iiii) BNL data on $\pi
N\to K\bar K N$. The analysis points to the existence of four comparatively
narrow scalar resonances which correspond to the following poles of the
scattering amplitude (in MeV): $(1015\pm 15)- i(43\pm 8)$, $(1300\pm
20)-i(120\pm 20)$, $(1499\pm 8)-i(65\pm 10)$ and $(1780\pm 30)-i(125\pm 70)$.
The scattering amplitude also has a fifth pole $f_0(1530^{+90}_{-250})$ at the
complex mass $(1530^{+90}_{-250}) - i(560\pm 140)$. The masses of the K-matrix
poles (bare states) are at $720\pm 100$ MeV, $1230\pm 50$ MeV, $1260\pm 30$
MeV, $1600\pm 50$ MeV and $1810\pm 30$ MeV. The quark content of the bare
states is analyzed using the values of their couplings to the $\pi\pi$, $K\bar
K$, $\eta\eta$ and $\eta\eta'$. It is shown that one of the bare states in the
mass region 1200-1600 MeV is superfluous for the $q\bar q$ classification and
should be considered as the lightest glueball.
| [
{
"created": "Fri, 18 Oct 1996 11:39:35 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Anisovich",
"V. V.",
""
],
[
"Prokoshkin",
"Yu. D.",
""
],
[
"Sarantsev",
"A. V.",
""
]
] | A classification of the $IJ^{PC}=00^{++}$ mesons is performed on the basis of the K-matrix analysis of meson spectra in the reactions: (i) GAMS data on $\pi p\to \pi^0\pi^0 n$, $\eta\eta n$, $\eta\eta' n$; (ii) Crystal Barrel data on $p\bar p~(at~rest)\to \pi^0\pi^0\pi^0$, $\pi^0\pi^0\eta$, $\pi^0\eta\eta$; (iii) CERN-M\"unich data on $\pi p\to \pi^+\pi^- n$; (iiii) BNL data on $\pi N\to K\bar K N$. The analysis points to the existence of four comparatively narrow scalar resonances which correspond to the following poles of the scattering amplitude (in MeV): $(1015\pm 15)- i(43\pm 8)$, $(1300\pm 20)-i(120\pm 20)$, $(1499\pm 8)-i(65\pm 10)$ and $(1780\pm 30)-i(125\pm 70)$. The scattering amplitude also has a fifth pole $f_0(1530^{+90}_{-250})$ at the complex mass $(1530^{+90}_{-250}) - i(560\pm 140)$. The masses of the K-matrix poles (bare states) are at $720\pm 100$ MeV, $1230\pm 50$ MeV, $1260\pm 30$ MeV, $1600\pm 50$ MeV and $1810\pm 30$ MeV. The quark content of the bare states is analyzed using the values of their couplings to the $\pi\pi$, $K\bar K$, $\eta\eta$ and $\eta\eta'$. It is shown that one of the bare states in the mass region 1200-1600 MeV is superfluous for the $q\bar q$ classification and should be considered as the lightest glueball. |
1209.3714 | S. Weinzierl | S. M\"uller-Stach, S. Weinzierl, R. Zayadeh | From motives to differential equations for loop integrals | 7 pages, talk given at Loops and Legs 2012 | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this talk we discuss how ideas from the theory of mixed Hodge structures
can be used to find differential equations for Feynman integrals. In particular
we discuss the two-loop sunrise graph in two dimensions and show that these
methods lead to a differential equation which is simpler than the ones obtained
from integration-by-parts.
| [
{
"created": "Mon, 17 Sep 2012 16:33:44 GMT",
"version": "v1"
}
] | 2012-09-18 | [
[
"Müller-Stach",
"S.",
""
],
[
"Weinzierl",
"S.",
""
],
[
"Zayadeh",
"R.",
""
]
] | In this talk we discuss how ideas from the theory of mixed Hodge structures can be used to find differential equations for Feynman integrals. In particular we discuss the two-loop sunrise graph in two dimensions and show that these methods lead to a differential equation which is simpler than the ones obtained from integration-by-parts. |
1001.2308 | Fuminobu Takahashi | Paul H. Frampton, Masahiro Kawasaki, Fuminobu Takahashi, Tsutomu T.
Yanagida | Primordial Black Holes as All Dark Matter | 14 pages, 2 figures, a version to appear in JCAP. | null | 10.1088/1475-7516/2010/04/023 | IPMU 09-0157 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We argue that a primordial black hole is a natural and unique candidate for
all dark matter. We show that, in a smooth-hybrid new double inflation model, a
right amount of the primordial black holes, with a sharply-defined mass, can be
produced at the end of the smooth-hybrid regime, through preheating. We first
consider masses < 10^(-7)M_sun which are allowed by all the previous
constraints. We next discuss much heavier mass 10^5 M_sun hinted at by entropy,
and galactic size evolution, arguments. Effects on the running of the scalar
spectral index are computed.
| [
{
"created": "Wed, 13 Jan 2010 21:03:21 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Apr 2010 14:50:29 GMT",
"version": "v2"
}
] | 2015-05-18 | [
[
"Frampton",
"Paul H.",
""
],
[
"Kawasaki",
"Masahiro",
""
],
[
"Takahashi",
"Fuminobu",
""
],
[
"Yanagida",
"Tsutomu T.",
""
]
] | We argue that a primordial black hole is a natural and unique candidate for all dark matter. We show that, in a smooth-hybrid new double inflation model, a right amount of the primordial black holes, with a sharply-defined mass, can be produced at the end of the smooth-hybrid regime, through preheating. We first consider masses < 10^(-7)M_sun which are allowed by all the previous constraints. We next discuss much heavier mass 10^5 M_sun hinted at by entropy, and galactic size evolution, arguments. Effects on the running of the scalar spectral index are computed. |
0904.3816 | Nobuhito Maru | Nobuhito Maru and Motoi Tachibana | Meson-Nucleon Coupling from AdS/QCD | 20 pages, final version to appear in EPJC | Eur.Phys.J.C63:123-132,2009 | 10.1140/epjc/s10052-009-1096-x | SAGA-HE-251 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this manuscript, a unified approach to hadron physics from holographic
point of view is described. After introduction of a general setup for
meson-nucleon system based on the bottom-up approach of QCD (AdS/QCD), as an
illustration, we specifically examine meson-nucleon couplings. This is an
example of the notion we call "holographic unification" in hadron physics.
| [
{
"created": "Fri, 24 Apr 2009 07:44:35 GMT",
"version": "v1"
},
{
"created": "Sat, 25 Apr 2009 06:02:55 GMT",
"version": "v2"
},
{
"created": "Sun, 28 Jun 2009 01:44:35 GMT",
"version": "v3"
}
] | 2009-09-24 | [
[
"Maru",
"Nobuhito",
""
],
[
"Tachibana",
"Motoi",
""
]
] | In this manuscript, a unified approach to hadron physics from holographic point of view is described. After introduction of a general setup for meson-nucleon system based on the bottom-up approach of QCD (AdS/QCD), as an illustration, we specifically examine meson-nucleon couplings. This is an example of the notion we call "holographic unification" in hadron physics. |
hep-ph/0312311 | Erhan Iltan | E. Iltan | The $\mu\to e\gamma$ and $\tau\to \mu\gamma$ decays in the general two
Higgs Doublet model with the inclusion of one universal extra dimension | 16 Pages, 8 Figures | JHEP 0402 (2004) 065 | 10.1088/1126-6708/2004/02/065 | null | hep-ph | null | We study the effect of one universal extra dimension on the branching ratios
of the lepton flavor violating processes \mu\to e\gamma and \tau\to \mu\gamma
in the general two Higgs doublet model. We observe that these new effects are
tiny for the small values of the compactification radius R. Furthermore, we see
that these effects are comparable with the branching ratio obtained without
including extra dimension, if the neutral Higgs bosons are nearly degenerate
and the complexity of the Yukawa coupling, inducing the vertex tau-tau-$h^0
(A^0)$, is large.
| [
{
"created": "Mon, 22 Dec 2003 11:07:43 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Iltan",
"E.",
""
]
] | We study the effect of one universal extra dimension on the branching ratios of the lepton flavor violating processes \mu\to e\gamma and \tau\to \mu\gamma in the general two Higgs doublet model. We observe that these new effects are tiny for the small values of the compactification radius R. Furthermore, we see that these effects are comparable with the branching ratio obtained without including extra dimension, if the neutral Higgs bosons are nearly degenerate and the complexity of the Yukawa coupling, inducing the vertex tau-tau-$h^0 (A^0)$, is large. |
1903.12126 | Timo K\"arkk\"ainen | Katri Huitu, Niko Koivunen and Timo J. K\"arkk\"ainen | Neutrino mass via linear seesaw, 331-model and Froggatt-Nielsen
mechanism | Poster presented at NuPhys2018 (London, 19-21 December 2018). 5
pages, LaTeX, HIP report HIP-2019-12/TH | null | null | NuPhys2018-K\"arkk\"ainen | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this paper, we introduce an extension of the Standard Model, based on
SU(3)$_\mathrm{C}\times $SU(3)$_\mathrm{L}\times $U(1)$_X$ gauge symmetry
(331-model). The 331-models traditionally explain the number of fermion familes
in nature. In our model the Froggatt-Nielsen mechanism is incorporated into the
331-setting in a particularly economical fashion. The model utilizes the both
the Froggatt-Nielsen and linear seesaw mechanisms to explain the observed
fermion mass hierarchies and lightness of neutrinos. In our numerical analysis
we found that a $\sim$ 50 TeV new physics scale is able to reproduce correctly
all the fermion masses and mixing matrices, including neutrino masses, mass
squared differences and mixing matrix.
| [
{
"created": "Thu, 28 Mar 2019 17:11:03 GMT",
"version": "v1"
}
] | 2019-03-29 | [
[
"Huitu",
"Katri",
""
],
[
"Koivunen",
"Niko",
""
],
[
"Kärkkäinen",
"Timo J.",
""
]
] | In this paper, we introduce an extension of the Standard Model, based on SU(3)$_\mathrm{C}\times $SU(3)$_\mathrm{L}\times $U(1)$_X$ gauge symmetry (331-model). The 331-models traditionally explain the number of fermion familes in nature. In our model the Froggatt-Nielsen mechanism is incorporated into the 331-setting in a particularly economical fashion. The model utilizes the both the Froggatt-Nielsen and linear seesaw mechanisms to explain the observed fermion mass hierarchies and lightness of neutrinos. In our numerical analysis we found that a $\sim$ 50 TeV new physics scale is able to reproduce correctly all the fermion masses and mixing matrices, including neutrino masses, mass squared differences and mixing matrix. |
1503.03760 | Dani\"el Boer | D. Boer, M.G.A. Buffing, P.J. Mulders | Operator analysis of $p_T$-widths of TMDs | 10 pages, no figures; expanded discussions, matches version accepted
by JHEP | null | 10.1007/JHEP08(2015)053 | NIKHEF 2015-007 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Transverse momentum dependent (TMD) parton distribution functions (PDFs),
TMDs for short, are defined as the Fourier transform of matrix elements of
nonlocal combinations of quark and gluon fields. The nonlocality is bridged by
gauge links, which for TMDs have characteristic paths (future or past
pointing), giving rise to a process dependence that breaks universality. It is
possible, however, to construct sets of universal TMDs of which in a given
process particular combinations are needed with calculable, process-dependent,
coefficients. This occurs for both T-odd and T-even TMDs, including also the
{\it unpolarized} quark and gluon TMDs. This extends the by now well-known
example of T-odd TMDs that appear with opposite sign in single-spin azimuthal
asymmetries in semi-inclusive deep inelastic scattering or in the Drell-Yan
process. In this paper we analyze the cases where TMDs enter multiplied by
products of two transverse momenta, which includes besides the $p_T$-broadening
observable, also instances with rank two structures. To experimentally
demonstrate the process dependence of the latter cases requires measurements of
second harmonic azimuthal asymmetries, while the $p_T$-broadening will require
measurements of processes beyond semi-inclusive deep inelastic scattering or
the Drell-Yan process. Furthermore, we propose specific quantities that will
allow for theoretical studies of the process dependence of TMDs using lattice
QCD calculations.
| [
{
"created": "Thu, 12 Mar 2015 15:06:42 GMT",
"version": "v1"
},
{
"created": "Sat, 11 Jul 2015 13:14:45 GMT",
"version": "v2"
}
] | 2015-09-30 | [
[
"Boer",
"D.",
""
],
[
"Buffing",
"M. G. A.",
""
],
[
"Mulders",
"P. J.",
""
]
] | Transverse momentum dependent (TMD) parton distribution functions (PDFs), TMDs for short, are defined as the Fourier transform of matrix elements of nonlocal combinations of quark and gluon fields. The nonlocality is bridged by gauge links, which for TMDs have characteristic paths (future or past pointing), giving rise to a process dependence that breaks universality. It is possible, however, to construct sets of universal TMDs of which in a given process particular combinations are needed with calculable, process-dependent, coefficients. This occurs for both T-odd and T-even TMDs, including also the {\it unpolarized} quark and gluon TMDs. This extends the by now well-known example of T-odd TMDs that appear with opposite sign in single-spin azimuthal asymmetries in semi-inclusive deep inelastic scattering or in the Drell-Yan process. In this paper we analyze the cases where TMDs enter multiplied by products of two transverse momenta, which includes besides the $p_T$-broadening observable, also instances with rank two structures. To experimentally demonstrate the process dependence of the latter cases requires measurements of second harmonic azimuthal asymmetries, while the $p_T$-broadening will require measurements of processes beyond semi-inclusive deep inelastic scattering or the Drell-Yan process. Furthermore, we propose specific quantities that will allow for theoretical studies of the process dependence of TMDs using lattice QCD calculations. |
2202.12305 | Matthias Steinhauser | Marvin Gerlach, Ulrich Nierste, Vladyslav Shtabovenko, Matthias
Steinhauser | The width difference in \bbm\ at order $\alpha_s$ and beyond | 36 pages | null | null | P3H-22-019, TTP22-012 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We complete the calculation of the element $\Gamma_{12}^q$ of the decay
matrix in $B_q-\bar{B}_q$ mixing, $q=d,s$, to order $\alpha_s$ in the leading
power of the Heavy Quark Expansion. To this end we compute one- and two-loop
contributions involving two four-quark penguin operators. Furthermore, we
present two-loop QCD corrections involving a chromomagnetic operator and either
a current-current or four-quark penguin operator. Such contributions are of
order $\alpha_s^2$, i.e. next-to-next-to-leading-order. We also present
one-loop and two-loop results involving two chromomagnetic operators which are
formally of next-to-next-to-leading and next-to-next-to-next-to-leading-order,
respectively. With our new corrections we obtain the Standard-Model prediction
$\Delta\Gamma_s/\Delta M_s= (5.20\pm 0.69)\cdot 10^{-3}$ if $\Gamma_{12}^s$ is
expressed in terms of the $\overline{\rm MS}$ b-quark mass, while we find
$\Delta \Gamma_s/\Delta M_s= (4.70\pm 0.96)\cdot 10^{-3}$ instead for the use
of the pole mass.
| [
{
"created": "Thu, 24 Feb 2022 19:00:02 GMT",
"version": "v1"
}
] | 2022-02-28 | [
[
"Gerlach",
"Marvin",
""
],
[
"Nierste",
"Ulrich",
""
],
[
"Shtabovenko",
"Vladyslav",
""
],
[
"Steinhauser",
"Matthias",
""
]
] | We complete the calculation of the element $\Gamma_{12}^q$ of the decay matrix in $B_q-\bar{B}_q$ mixing, $q=d,s$, to order $\alpha_s$ in the leading power of the Heavy Quark Expansion. To this end we compute one- and two-loop contributions involving two four-quark penguin operators. Furthermore, we present two-loop QCD corrections involving a chromomagnetic operator and either a current-current or four-quark penguin operator. Such contributions are of order $\alpha_s^2$, i.e. next-to-next-to-leading-order. We also present one-loop and two-loop results involving two chromomagnetic operators which are formally of next-to-next-to-leading and next-to-next-to-next-to-leading-order, respectively. With our new corrections we obtain the Standard-Model prediction $\Delta\Gamma_s/\Delta M_s= (5.20\pm 0.69)\cdot 10^{-3}$ if $\Gamma_{12}^s$ is expressed in terms of the $\overline{\rm MS}$ b-quark mass, while we find $\Delta \Gamma_s/\Delta M_s= (4.70\pm 0.96)\cdot 10^{-3}$ instead for the use of the pole mass. |
2108.07752 | Saleh Hamdan | Saleh Hamdan | Dark Matter Freeze-out in a Matter Dominated Universe | PhD Thesis | null | null | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | The universe has evolved through several phases as its various constituents
dominated its energy content. Candidate dark matter particles may have
undergone freeze-out during any such phase. While the standard freeze-out
scenarios have been explored during the radiation-dominated era, and more
recently during scalar field decay, this work extends the study of dark matter
freeze-out to a potential early period during which the universe is
matter-dominated and its evolution adiabatic. Decoupling during an adiabatic
matter dominated era changes the freeze-out dynamics, since the Hubble rate is
parametrically different for matter and radiation domination. Furthermore, for
successful Big Bang Nucleosynthesis the state dominating the early universe
energy density must decay, this dilutes (or repopulates) the dark matter. As a
result, the masses and couplings required to match the observed dark matter
relic density can differ signifcantly from radiation dominated freeze-out.
| [
{
"created": "Tue, 17 Aug 2021 16:54:29 GMT",
"version": "v1"
}
] | 2021-08-18 | [
[
"Hamdan",
"Saleh",
""
]
] | The universe has evolved through several phases as its various constituents dominated its energy content. Candidate dark matter particles may have undergone freeze-out during any such phase. While the standard freeze-out scenarios have been explored during the radiation-dominated era, and more recently during scalar field decay, this work extends the study of dark matter freeze-out to a potential early period during which the universe is matter-dominated and its evolution adiabatic. Decoupling during an adiabatic matter dominated era changes the freeze-out dynamics, since the Hubble rate is parametrically different for matter and radiation domination. Furthermore, for successful Big Bang Nucleosynthesis the state dominating the early universe energy density must decay, this dilutes (or repopulates) the dark matter. As a result, the masses and couplings required to match the observed dark matter relic density can differ signifcantly from radiation dominated freeze-out. |
1805.01604 | Aleksas Mazeliauskas | Aleksi Kurkela, Aleksas Mazeliauskas, Jean-Fran\c{c}ois Paquet,
S\"oren Schlichting and Derek Teaney | Matching the Nonequilibrium Initial Stage of Heavy Ion Collisions to
Hydrodynamics with QCD Kinetic Theory | 7 pages, 4 figures, v2: typos corrected and minor changes, version
accepted for publication in Phys. Rev. Lett., see also our companion paper
arXiv:1805.00961 for the extensive details, for the code of linear kinetic
theory propagator KoMPoST used for this study see
https://github.com/KMPST/KoMPoST ; v3 updated references, published version | Phys. Rev. Lett. 122, 122302 (2019) | 10.1103/PhysRevLett.122.122302 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | High-energy nuclear collisions produce a nonequilibrium plasma of quarks and
gluons which thermalizes and exhibits hydrodynamic flow. There are currently no
practical frameworks to connect the early particle production in classical
field simulations to the subsequent hydrodynamic evolution. We build such a
framework using nonequilibrium Green's functions, calculated in QCD kinetic
theory, to propagate the initial energy-momentum tensor to the hydrodynamic
phase. We demonstrate that this approach can be easily incorporated into
existing hydrodynamic simulations, leading to stronger constraints on the
energy density at early times and the transport properties of the QCD medium.
Based on (conformal) scaling properties of the Green's functions, we further
obtain pragmatic bounds for the applicability of hydrodynamics in nuclear
collisions.
| [
{
"created": "Fri, 4 May 2018 04:45:07 GMT",
"version": "v1"
},
{
"created": "Wed, 9 Jan 2019 14:01:22 GMT",
"version": "v2"
},
{
"created": "Fri, 26 Apr 2019 19:46:59 GMT",
"version": "v3"
}
] | 2019-04-30 | [
[
"Kurkela",
"Aleksi",
""
],
[
"Mazeliauskas",
"Aleksas",
""
],
[
"Paquet",
"Jean-François",
""
],
[
"Schlichting",
"Sören",
""
],
[
"Teaney",
"Derek",
""
]
] | High-energy nuclear collisions produce a nonequilibrium plasma of quarks and gluons which thermalizes and exhibits hydrodynamic flow. There are currently no practical frameworks to connect the early particle production in classical field simulations to the subsequent hydrodynamic evolution. We build such a framework using nonequilibrium Green's functions, calculated in QCD kinetic theory, to propagate the initial energy-momentum tensor to the hydrodynamic phase. We demonstrate that this approach can be easily incorporated into existing hydrodynamic simulations, leading to stronger constraints on the energy density at early times and the transport properties of the QCD medium. Based on (conformal) scaling properties of the Green's functions, we further obtain pragmatic bounds for the applicability of hydrodynamics in nuclear collisions. |
2205.14012 | Selcuk Bilmis | T.M.Aliev, S.Bilmis, M.Savci | Analysis of FCNC $\Xi_{QQ} \to \Lambda_Q l^+ l^-$ decay in light-cone
sum rules | Figures for the variation of the form factors with respect to the
Borel mass parameter are added. And some typos are corrected | null | 10.1103/PhysRevD.106.034017 | null | hep-ph hep-lat | http://creativecommons.org/licenses/by/4.0/ | The weak decays of doubly heavy $\Xi_{QQ}$ baryon induced by flavor changing
$b \to d$ and $ c \to u$ flavor changing neutral current within the light cone
sum rules are studied. Using the parallel components of the light cone
distribution amplitudes for $\Lambda_Q$ baryon, the sum rules are constructed
and analyzed for the corresponding transition form factors. Having the results
for the form factors, the corresponding branching ratios for $\Xi_{QQ} \to
\Lambda_Q l^+ l^-$ decays are estimated. While the branching ratio due to $b
\to d$ transition is around $10^{-9}$, in $c \to u$ transition case, it is
found as around $10^{-13}$. Hence, $\Xi_{bb} \to \Lambda_b l^+ l^-$ decay has
the potential of being discovered at LHCb. However, $\Xi_{bb} \to \Lambda_b l^+
l^-$ is difficult to be measured due to the extremely small values of obtained
branching ratio. Our results on the branching ratio are also compared with the
results of the light-front approach.
| [
{
"created": "Fri, 27 May 2022 14:34:26 GMT",
"version": "v1"
},
{
"created": "Mon, 30 May 2022 11:36:21 GMT",
"version": "v2"
},
{
"created": "Wed, 3 Aug 2022 17:53:28 GMT",
"version": "v3"
}
] | 2022-08-31 | [
[
"Aliev",
"T. M.",
""
],
[
"Bilmis",
"S.",
""
],
[
"Savci",
"M.",
""
]
] | The weak decays of doubly heavy $\Xi_{QQ}$ baryon induced by flavor changing $b \to d$ and $ c \to u$ flavor changing neutral current within the light cone sum rules are studied. Using the parallel components of the light cone distribution amplitudes for $\Lambda_Q$ baryon, the sum rules are constructed and analyzed for the corresponding transition form factors. Having the results for the form factors, the corresponding branching ratios for $\Xi_{QQ} \to \Lambda_Q l^+ l^-$ decays are estimated. While the branching ratio due to $b \to d$ transition is around $10^{-9}$, in $c \to u$ transition case, it is found as around $10^{-13}$. Hence, $\Xi_{bb} \to \Lambda_b l^+ l^-$ decay has the potential of being discovered at LHCb. However, $\Xi_{bb} \to \Lambda_b l^+ l^-$ is difficult to be measured due to the extremely small values of obtained branching ratio. Our results on the branching ratio are also compared with the results of the light-front approach. |
1801.10348 | Ralf-Arno Tripolt | Ralf-Arno Tripolt, Philipp Gubler, Maksim Ulybyshev, Lorenz von Smekal | Numerical analytic continuation of Euclidean data | 32 pages, 19 figures | Comput.Phys.Commun. 237 (2019) 129-142 | 10.1016/j.cpc.2018.11.012 | null | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we present a direct comparison of three different numerical
analytic continuation methods: the Maximum Entropy Method, the Backus-Gilbert
method and the Schlessinger point or Resonances Via Pad\'{e} method. First, we
perform a benchmark test based on a model spectral function and study the
regime of applicability of these methods depending on the number of input
points and their statistical error. We then apply these methods to more
realistic examples, namely to numerical data on Euclidean propagators obtained
from a Functional Renormalization Group calculation, to data from a lattice
Quantum Chromodynamics simulation and to data obtained from a tight-binding
model for graphene in order to extract the electrical conductivity.
| [
{
"created": "Wed, 31 Jan 2018 08:39:22 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Nov 2018 15:06:24 GMT",
"version": "v2"
}
] | 2019-03-05 | [
[
"Tripolt",
"Ralf-Arno",
""
],
[
"Gubler",
"Philipp",
""
],
[
"Ulybyshev",
"Maksim",
""
],
[
"von Smekal",
"Lorenz",
""
]
] | In this work we present a direct comparison of three different numerical analytic continuation methods: the Maximum Entropy Method, the Backus-Gilbert method and the Schlessinger point or Resonances Via Pad\'{e} method. First, we perform a benchmark test based on a model spectral function and study the regime of applicability of these methods depending on the number of input points and their statistical error. We then apply these methods to more realistic examples, namely to numerical data on Euclidean propagators obtained from a Functional Renormalization Group calculation, to data from a lattice Quantum Chromodynamics simulation and to data obtained from a tight-binding model for graphene in order to extract the electrical conductivity. |
hep-ph/9609238 | Hong | Richard Hong Tuan | Simple Amplitudes for \Phi^3 Feynman Ladder Graphs | 11 Plain TeX pages, 2 PostScript figures included | Mod.Phys.Lett. A12 (1997) 811-820 | 10.1142/S0217732397000832 | Orsay - LPTHE 96/62 | hep-ph | null | Recently, we proposed a new approach for calculating Feynman graphs amplitude
using the Gaussian representation for propagators which was proven to be exact
in the limit of graphs having an infinite number of loops. Regge behavior was
also found in a completely new way and the leading Regge trajectory calculated.
Here we present symmetry arguments justifying the simple form used for the
polynomials in the Feynman parameters $\bar \alpha _{\ell}$, where $\bar \alpha
_{\ell}$ is the mean-value for these parameters, appearing in the amplitude for
the ladder graphs. (Taking mean-values is equivalent to the Gaussian
representation for propagators).
| [
{
"created": "Tue, 3 Sep 1996 15:31:06 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Tuan",
"Richard Hong",
""
]
] | Recently, we proposed a new approach for calculating Feynman graphs amplitude using the Gaussian representation for propagators which was proven to be exact in the limit of graphs having an infinite number of loops. Regge behavior was also found in a completely new way and the leading Regge trajectory calculated. Here we present symmetry arguments justifying the simple form used for the polynomials in the Feynman parameters $\bar \alpha _{\ell}$, where $\bar \alpha _{\ell}$ is the mean-value for these parameters, appearing in the amplitude for the ladder graphs. (Taking mean-values is equivalent to the Gaussian representation for propagators). |
hep-ph/0408022 | Bo-Qiang Ma | Bo-Qiang Ma, Ivan Schmidt, and Jian-Jun Yang | Particle-Antiparticle Asymmetries of $\Lambda$ Production in
Hadron-Nucleon Collisions | 14 LaTex pages, 4 figures, to appear in Phys. Lett. B | Phys.Lett. B598 (2004) 211-217 | 10.1016/j.physletb.2004.07.049 | Preprint USM-TH-142 | hep-ph hep-ex nucl-ex nucl-th | null | The particle-antiparticle asymmetries of $\Lambda$ production in 250 GeV/c
$\pi^{\pm}$, $K^{\pm}$, and $p$ --nucleon collisions are studied with two model
parametrizations of quark to $\Lambda$ fragmentation functions. It is shown
that the available data can be qualitatively explained by the calculated
results in both the quark-diquark model and a pQCD based analysis of
fragmentation functions. The differences in the two model predictions are
significant for $K^{\pm}$ beams, and high precision measurements of the
asymmetries with detailed $x_F$ and $P_T$ information can discriminate between
different predictions.
| [
{
"created": "Tue, 3 Aug 2004 00:11:39 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Ma",
"Bo-Qiang",
""
],
[
"Schmidt",
"Ivan",
""
],
[
"Yang",
"Jian-Jun",
""
]
] | The particle-antiparticle asymmetries of $\Lambda$ production in 250 GeV/c $\pi^{\pm}$, $K^{\pm}$, and $p$ --nucleon collisions are studied with two model parametrizations of quark to $\Lambda$ fragmentation functions. It is shown that the available data can be qualitatively explained by the calculated results in both the quark-diquark model and a pQCD based analysis of fragmentation functions. The differences in the two model predictions are significant for $K^{\pm}$ beams, and high precision measurements of the asymmetries with detailed $x_F$ and $P_T$ information can discriminate between different predictions. |
0705.0254 | Valery Lyubovitskij | Amand Faessler, Thomas Gutsche, Valery E. Lyubovitskij, Yong-Liang Ma | Strong and radiative decays of the Ds0*(2317) meson in the DK-molecule
picture | 22 pages, 4 figures, accepted for publication in Phys. Rev. D | Phys.Rev.D76:014005,2007 | 10.1103/PhysRevD.76.014005 | null | hep-ph | null | We consider a possible interpretation of the new charm-strange meson
Ds0*(2317) as a hadronic molecule - a bound state of D and K mesons. Using an
effective Lagrangian approach we calculate the strong Ds0* to Ds pi0 and
radiative Ds0* to Ds* gamma decays. A new impact related to the DK molecular
structure of the Ds0*(2317) meson is that the presence of u(d) quarks in the D
and K mesons gives rise to a direct strong isospin-violating transition Ds0* to
Ds pi0 in addition to the decay mechanism induced by eta-pi0 mixing considered
previously. We show that the direct transition dominates over the eta-pi0
mixing transition in the Ds0* to Ds pi0 decay. Our results for the partial
decay widths are consistent with previous calculations.
| [
{
"created": "Wed, 2 May 2007 13:18:39 GMT",
"version": "v1"
},
{
"created": "Fri, 8 Jun 2007 09:37:08 GMT",
"version": "v2"
},
{
"created": "Tue, 10 Jul 2007 06:53:38 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Faessler",
"Amand",
""
],
[
"Gutsche",
"Thomas",
""
],
[
"Lyubovitskij",
"Valery E.",
""
],
[
"Ma",
"Yong-Liang",
""
]
] | We consider a possible interpretation of the new charm-strange meson Ds0*(2317) as a hadronic molecule - a bound state of D and K mesons. Using an effective Lagrangian approach we calculate the strong Ds0* to Ds pi0 and radiative Ds0* to Ds* gamma decays. A new impact related to the DK molecular structure of the Ds0*(2317) meson is that the presence of u(d) quarks in the D and K mesons gives rise to a direct strong isospin-violating transition Ds0* to Ds pi0 in addition to the decay mechanism induced by eta-pi0 mixing considered previously. We show that the direct transition dominates over the eta-pi0 mixing transition in the Ds0* to Ds pi0 decay. Our results for the partial decay widths are consistent with previous calculations. |
hep-ph/9712322 | Keith Dienes | Keith R. Dienes and Christopher Kolda | Twenty Open Questions in Supersymmetric Particle Physics | 64 pages, LaTeX, 2 figures | null | null | IASSNS-HEP-97/68, CERN-TH/97-292 (December 1997) | hep-ph hep-th | null | We give a brief overview of 20 open theoretical questions in supersymmetric
particle physics. The 20 questions we have chosen range from the GeV scale to
the Planck scale, and include issues pertaining to the Minimal Supersymmetric
Standard Model and its extensions, SUSY-breaking, cosmology, grand unified
theories, and string theory. Throughout, our goal is to address those topics in
which supersymmetry plays a fundamental role, and which are areas of active
research in the field. This survey is written at an introductory level and is
aimed at people who are not necessarily experts in the field.
(To appear as an Overview Chapter in the review volume "Perspectives on
Supersymmetry", edited by G. Kane, to be published by World Scientific.)
| [
{
"created": "Tue, 9 Dec 1997 23:41:29 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Dienes",
"Keith R.",
""
],
[
"Kolda",
"Christopher",
""
]
] | We give a brief overview of 20 open theoretical questions in supersymmetric particle physics. The 20 questions we have chosen range from the GeV scale to the Planck scale, and include issues pertaining to the Minimal Supersymmetric Standard Model and its extensions, SUSY-breaking, cosmology, grand unified theories, and string theory. Throughout, our goal is to address those topics in which supersymmetry plays a fundamental role, and which are areas of active research in the field. This survey is written at an introductory level and is aimed at people who are not necessarily experts in the field. (To appear as an Overview Chapter in the review volume "Perspectives on Supersymmetry", edited by G. Kane, to be published by World Scientific.) |
hep-ph/9607473 | Enrico Nardi | Yuval Grossman, Zoltan Ligeti and Enrico Nardi | $B \to\tau^+ \tau^- (X)$ decays: first constraints and phenomenological
implications | 16 pages, LaTeX, no figures | Phys.Rev.D55:2768-2773,1997 | 10.1103/PhysRevD.55.2768 | WIS-96/33/Jul-PH, CALT-68-2059 | hep-ph | null | The study of $B \to \tau^+ \tau^- (X)$ decays can provide us with a better
understanding of the third generation, and can be a useful probe of physics
beyond the standard model. We present a model independent analysis of these
decays. We classify new physics that can largely enhance the decay rates and we
discuss the constraints implied by other processes. Experimentally, flavor
changing neutral current $B$ decays into final state $\tau$'s are still
unconstrained. Searches for $B$ decays with large missing energy at LEP provide
the first limits. We estimate that existing data already imply bounds on the
$B_d \to \tau^+ \tau^-$, $B_s \to \tau^+ \tau^-$, and $B \to X \tau^+ \tau^-$
decay rates at the few percent level. Although these bounds are over four
orders of magnitude above the standard model predictions, they provide the
first constraints on some leptoquarks, and on some R-parity violating
couplings.
| [
{
"created": "Wed, 31 Jul 1996 07:06:46 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Grossman",
"Yuval",
""
],
[
"Ligeti",
"Zoltan",
""
],
[
"Nardi",
"Enrico",
""
]
] | The study of $B \to \tau^+ \tau^- (X)$ decays can provide us with a better understanding of the third generation, and can be a useful probe of physics beyond the standard model. We present a model independent analysis of these decays. We classify new physics that can largely enhance the decay rates and we discuss the constraints implied by other processes. Experimentally, flavor changing neutral current $B$ decays into final state $\tau$'s are still unconstrained. Searches for $B$ decays with large missing energy at LEP provide the first limits. We estimate that existing data already imply bounds on the $B_d \to \tau^+ \tau^-$, $B_s \to \tau^+ \tau^-$, and $B \to X \tau^+ \tau^-$ decay rates at the few percent level. Although these bounds are over four orders of magnitude above the standard model predictions, they provide the first constraints on some leptoquarks, and on some R-parity violating couplings. |
1512.00817 | Jorge S. Diaz | J.S. Diaz, F.R. Klinkhamer | Neutrino refraction by the cosmic neutrino background | 12 pages, v3: published version | Phys. Rev. D 93, 053004 (2016) | 10.1103/PhysRevD.93.053004 | KA-TP-23-2015 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have determined the dispersion relation of a neutrino test particle
propagating in the cosmic neutrino background. Describing the relic neutrinos
and antineutrinos from the hot big bang as a dense medium, a matter potential
or refractive index is obtained. The vacuum neutrino mixing angles are
unchanged, but the energy of each mass state is modified. Using a matrix in the
space of neutrino species, the induced potential is decomposed into a part
which produces signatures in beta-decay experiments and another part which
modifies neutrino oscillations. The low temperature of the relic neutrinos
makes a direct detection extremely challenging. From a different point of view,
the identified refractive effects of the cosmic neutrino background constitute
an ultralow background for future experimental studies of nonvanishing Lorentz
violation in the neutrino sector.
| [
{
"created": "Wed, 2 Dec 2015 19:32:12 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Dec 2015 19:56:02 GMT",
"version": "v2"
},
{
"created": "Mon, 7 Mar 2016 20:33:56 GMT",
"version": "v3"
}
] | 2016-03-09 | [
[
"Diaz",
"J. S.",
""
],
[
"Klinkhamer",
"F. R.",
""
]
] | We have determined the dispersion relation of a neutrino test particle propagating in the cosmic neutrino background. Describing the relic neutrinos and antineutrinos from the hot big bang as a dense medium, a matter potential or refractive index is obtained. The vacuum neutrino mixing angles are unchanged, but the energy of each mass state is modified. Using a matrix in the space of neutrino species, the induced potential is decomposed into a part which produces signatures in beta-decay experiments and another part which modifies neutrino oscillations. The low temperature of the relic neutrinos makes a direct detection extremely challenging. From a different point of view, the identified refractive effects of the cosmic neutrino background constitute an ultralow background for future experimental studies of nonvanishing Lorentz violation in the neutrino sector. |
hep-ph/0308225 | Zhi-Zhong Xing | Zhi-zhong Xing | Direct CP Violation and Isospin Triangles of B->\pi\pi Decays | RevTex 9 pages (1 PS figure included). More discussions with new
equations and references added. Accepted for publication in PRD (Rapid
Communication) | Phys.Rev.D68:071301,2003 | 10.1103/PhysRevD.68.071301 | BIHEP-TH-2003-28 | hep-ph hep-ex | null | The recent observation of B^0_d->\pi^0\pi^0 and \bar{B}^0_d->\pi^0\pi^0 decay
modes allows us to make a fresh isospin analysis of B->\pi\pi transitions. We
find that current experimental data can impose some model-independent
constraints on the parameter space of direct CP violation in B_d->\pi^+\pi^-
and B_d->\pi^0\pi^0. Furthermore, we establish a direct relationship between
the weak phase \alpha and the charge-averaged branching fractions and
CP-violating asymmetries of B->\pi\pi decays.
| [
{
"created": "Fri, 22 Aug 2003 09:03:33 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Sep 2003 20:56:17 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Xing",
"Zhi-zhong",
""
]
] | The recent observation of B^0_d->\pi^0\pi^0 and \bar{B}^0_d->\pi^0\pi^0 decay modes allows us to make a fresh isospin analysis of B->\pi\pi transitions. We find that current experimental data can impose some model-independent constraints on the parameter space of direct CP violation in B_d->\pi^+\pi^- and B_d->\pi^0\pi^0. Furthermore, we establish a direct relationship between the weak phase \alpha and the charge-averaged branching fractions and CP-violating asymmetries of B->\pi\pi decays. |
1611.06085 | Krzysztof Golec-Biernat | Krzysztof Golec-Biernat and Anna Stasto | Unintegrated Double Parton Distributions - a Summary | presented at "Diffraction 2016", International Workshop on
Diffraction in High Energy Physics, Acireale (Catania, Sicily), Sept 2-8
2016, to be published in the conference proceedings by AIP | null | 10.1063/1.4977163 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present main elements of the construction of unintegrated double parton
distribution functions which depend on transverse momenta of partons. We follow
the method proposed by Kimber, Martin and Ryskin for a construction of
unintegrated single parton distributions from the standard parton distribution
functions.
| [
{
"created": "Fri, 18 Nov 2016 14:07:36 GMT",
"version": "v1"
}
] | 2017-04-05 | [
[
"Golec-Biernat",
"Krzysztof",
""
],
[
"Stasto",
"Anna",
""
]
] | We present main elements of the construction of unintegrated double parton distribution functions which depend on transverse momenta of partons. We follow the method proposed by Kimber, Martin and Ryskin for a construction of unintegrated single parton distributions from the standard parton distribution functions. |
1203.4029 | Xiang Liu | Qing-Yong Lin, Xiang Liu and Hu-Shan Xu | Revisiting the production of charmonium plus a light meson at PANDA | 10 pages, 2 tables, 9 figures. Version published in Phys. Rev. D | Phys.Rev.D86:034007,2012 | 10.1103/PhysRevD.86.034007 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we calculate the total cross sections and the center-of-mass
frame angular distributions of the charmonium production plus a light meson by
the low energy $p\bar{p}$ interaction. The results of $p\bar{p}\to \pi^0 \Psi$
with and without form factor (FF) indicate that the FF contribution in the
calculation cannot be ignored. The obtained cross section of $p\bar{p}\to \pi^0
J/\psi$ with FF can fit the E760 data well. We also predict the total cross
sections and the center-of-mass frame angular distributions of $p\bar{p}\to
\omega \Psi$, which show that these physical quantities are dependent on Pauli
($g_\omega$) and Dirac ($\kappa_\omega$) coupling constants of the $pp\omega$
interaction. Thus, $p\bar{p}\to \omega \Psi$ can be as the ideal channel to
test the different theoretical values of $g_\omega$ and $\kappa_\omega$.
Applying the formulae of $p\bar{p}\to \pi^0 \Psi$ and $p\bar{p}\to \omega
\Psi$, we predict the total cross sections of the $p\bar{p}\to \eta \Psi$ and
$p\bar{p}\to \rho \Psi$ reactions. Our results show a common behavior of the
charmonium production with a light meson by the $p\bar{p}$ interaction, where
the total cross section of the $\eta_c$ production is the largest one among all
discussed processes. The above observations can be directly tested at the
forthcoming $\bar{P}$ANDA experiment.
| [
{
"created": "Mon, 19 Mar 2012 03:41:54 GMT",
"version": "v1"
},
{
"created": "Tue, 10 Jul 2012 01:16:56 GMT",
"version": "v2"
},
{
"created": "Fri, 27 Jul 2012 08:38:44 GMT",
"version": "v3"
}
] | 2012-08-08 | [
[
"Lin",
"Qing-Yong",
""
],
[
"Liu",
"Xiang",
""
],
[
"Xu",
"Hu-Shan",
""
]
] | In this work, we calculate the total cross sections and the center-of-mass frame angular distributions of the charmonium production plus a light meson by the low energy $p\bar{p}$ interaction. The results of $p\bar{p}\to \pi^0 \Psi$ with and without form factor (FF) indicate that the FF contribution in the calculation cannot be ignored. The obtained cross section of $p\bar{p}\to \pi^0 J/\psi$ with FF can fit the E760 data well. We also predict the total cross sections and the center-of-mass frame angular distributions of $p\bar{p}\to \omega \Psi$, which show that these physical quantities are dependent on Pauli ($g_\omega$) and Dirac ($\kappa_\omega$) coupling constants of the $pp\omega$ interaction. Thus, $p\bar{p}\to \omega \Psi$ can be as the ideal channel to test the different theoretical values of $g_\omega$ and $\kappa_\omega$. Applying the formulae of $p\bar{p}\to \pi^0 \Psi$ and $p\bar{p}\to \omega \Psi$, we predict the total cross sections of the $p\bar{p}\to \eta \Psi$ and $p\bar{p}\to \rho \Psi$ reactions. Our results show a common behavior of the charmonium production with a light meson by the $p\bar{p}$ interaction, where the total cross section of the $\eta_c$ production is the largest one among all discussed processes. The above observations can be directly tested at the forthcoming $\bar{P}$ANDA experiment. |
1101.0918 | Saeed Uddin | Saeed Uddin, Jan Shabir Ahmad, Waseem Bashir and Riyaz Ahmad Bhat | A Unified Approach towards Describing Rapidity and Transverse Momentum
Distributions in Thermal Freeze-Out Model | 22 pages, 11 figures | null | 10.1088/0954-3899/39/1/015012 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have attempted to describe the rapidity and transverse momentum spectra,
simultaneously, of the hadrons produced in the Ultra-relativistic Nuclear
Collisions. This we have tried to achieve in a single statistical thermal
freeze-out model using single set of parameters. We assume the formation of a
hadronic gas in thermo-chemical equilibrium at the freeze-out. The model
incorporates a longitudinal as well as a transverse hydrodynamic flow. We have
also found that the role of heavier hadronic resonance decay is important in
explaining the particle spectra.
| [
{
"created": "Wed, 5 Jan 2011 09:52:29 GMT",
"version": "v1"
}
] | 2015-05-20 | [
[
"Uddin",
"Saeed",
""
],
[
"Ahmad",
"Jan Shabir",
""
],
[
"Bashir",
"Waseem",
""
],
[
"Bhat",
"Riyaz Ahmad",
""
]
] | We have attempted to describe the rapidity and transverse momentum spectra, simultaneously, of the hadrons produced in the Ultra-relativistic Nuclear Collisions. This we have tried to achieve in a single statistical thermal freeze-out model using single set of parameters. We assume the formation of a hadronic gas in thermo-chemical equilibrium at the freeze-out. The model incorporates a longitudinal as well as a transverse hydrodynamic flow. We have also found that the role of heavier hadronic resonance decay is important in explaining the particle spectra. |
hep-ph/9807425 | Helmut Neufeld | H. Neufeld (CERN) | The Super-Heat-Kernel Expansion and the Renormalization of the
Pion-Nucleon Interaction | 15 pages, Latex | Eur.Phys.J.C7:355-362,1999 | 10.1007/s100529801004 | CERN-TH/98-231 | hep-ph | null | A recently proposed super-heat-kernel technique is applied to heavy baryon
chiral perturbation theory with two flavours. A previous result for the
one-loop divergences of the pion-nucleon system is confirmed, giving at the
same time an impressive demonstration of the efficiency of the new method. The
cumbersome and tedious calculations of the conventional approach are now
reduced to a few simple algebraic manipulations. The present computational
scheme is not restricted to chiral perturbation theory, but can easily be
applied or extended to any (in general non-renormalizable) theory with
boson-fermion interactions.
| [
{
"created": "Mon, 20 Jul 1998 17:41:03 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Neufeld",
"H.",
"",
"CERN"
]
] | A recently proposed super-heat-kernel technique is applied to heavy baryon chiral perturbation theory with two flavours. A previous result for the one-loop divergences of the pion-nucleon system is confirmed, giving at the same time an impressive demonstration of the efficiency of the new method. The cumbersome and tedious calculations of the conventional approach are now reduced to a few simple algebraic manipulations. The present computational scheme is not restricted to chiral perturbation theory, but can easily be applied or extended to any (in general non-renormalizable) theory with boson-fermion interactions. |
hep-ph/9512292 | Tim Stelzer | T. Stelzer and S. Willenbrock | Spin Correlation in Top-Quark Production at Hadron Colliders | Version to appear in Phys. Lett. B | Phys.Lett.B374:169-172,1996 | 10.1016/0370-2693(96)00178-5 | ILL-(TH)-95-33 | hep-ph | null | We propose techniques to observe the correlation of the spins of top quarks
and antiquarks at the Tevatron and the LHC. Observation of the spin correlation
would confirm that the top quark decays before its spin flips, and would place
a lower bound on the top-quark width and V_tb. The spin correlation may also be
a useful tool to study the weak decay amplitude of the top quark.
| [
{
"created": "Wed, 13 Dec 1995 08:09:12 GMT",
"version": "v1"
},
{
"created": "Thu, 22 Feb 1996 19:02:25 GMT",
"version": "v2"
},
{
"created": "Tue, 19 Mar 1996 15:49:24 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Stelzer",
"T.",
""
],
[
"Willenbrock",
"S.",
""
]
] | We propose techniques to observe the correlation of the spins of top quarks and antiquarks at the Tevatron and the LHC. Observation of the spin correlation would confirm that the top quark decays before its spin flips, and would place a lower bound on the top-quark width and V_tb. The spin correlation may also be a useful tool to study the weak decay amplitude of the top quark. |
1603.01383 | Kfir Blum | Kfir Blum, Ryosuke Sato, Tracy R. Slatyer | Self-consistent Calculation of the Sommerfeld Enhancement | 13 pages, 4 figures. v2: added clarifications, match journal version | null | 10.1088/1475-7516/2016/06/021 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A calculation of the Sommerfeld enhancement is presented and applied to the
problem of s-wave non-relativistic dark matter annihilation. The difference
from previous computations in the literature is that the effect of the
underlying short-range scattering process is consistently included together
with the long-range force in the effective QM Schr\"odinger problem. Our
procedure satisfies partial-wave unitarity where previous calculations fail. We
provide analytic results for some potentials of phenomenological relevance.
| [
{
"created": "Fri, 4 Mar 2016 09:05:14 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Jun 2016 08:21:19 GMT",
"version": "v2"
}
] | 2016-06-29 | [
[
"Blum",
"Kfir",
""
],
[
"Sato",
"Ryosuke",
""
],
[
"Slatyer",
"Tracy R.",
""
]
] | A calculation of the Sommerfeld enhancement is presented and applied to the problem of s-wave non-relativistic dark matter annihilation. The difference from previous computations in the literature is that the effect of the underlying short-range scattering process is consistently included together with the long-range force in the effective QM Schr\"odinger problem. Our procedure satisfies partial-wave unitarity where previous calculations fail. We provide analytic results for some potentials of phenomenological relevance. |
1511.05030 | Masaki Yamada | Masahiro Kawasaki, Fuminobu Takahashi, Masaki Yamada | Suppressing the QCD Axion Abundance by Hidden Monopoles | 6 pages, 1 figure | null | 10.1016/j.physletb.2015.12.075 | TU-1011; DESY 15-216 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Witten effect of hidden monopoles on the QCD axion dynamics, and
show that its abundance as well as isocurvature perturbations can be
significantly suppressed if there is a sufficient amount of hidden monopoles.
When the hidden monopoles make up a significant fraction of dark matter, the
Witten effect suppresses the abundance of axion with the decay constant smaller
than $10^{12}$ GeV. The cosmological domain wall problem of the QCD axion can
also be avoided, relaxing the upper bound on the decay constant when the
Peccei-Quinn symmetry is spontaneously broken after inflation.
| [
{
"created": "Mon, 16 Nov 2015 16:55:21 GMT",
"version": "v1"
}
] | 2016-02-17 | [
[
"Kawasaki",
"Masahiro",
""
],
[
"Takahashi",
"Fuminobu",
""
],
[
"Yamada",
"Masaki",
""
]
] | We study the Witten effect of hidden monopoles on the QCD axion dynamics, and show that its abundance as well as isocurvature perturbations can be significantly suppressed if there is a sufficient amount of hidden monopoles. When the hidden monopoles make up a significant fraction of dark matter, the Witten effect suppresses the abundance of axion with the decay constant smaller than $10^{12}$ GeV. The cosmological domain wall problem of the QCD axion can also be avoided, relaxing the upper bound on the decay constant when the Peccei-Quinn symmetry is spontaneously broken after inflation. |
1110.0470 | James Unwin | James Unwin | A sharp 141 GeV Higgs prediction from environmental selection | 7 pages, 2 figures, 2 tables. v2: Minor corrections and amendments,
references added | null | 10.1103/PhysRevD.86.095002 | OUTP-11-54P | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct an environmentally selected supersymmetric standard model with a
single Higgs doublet, in analogy with the work of Hall and Nomura. The low
energy spectrum presents only the standard model states with a single Higgs and
TeV scale gauginos. The model features a precise Higgs mass prediction
m_H=141\pm 2 GeV and the neutral wino provides a viable dark matter candidate.
| [
{
"created": "Mon, 3 Oct 2011 20:00:05 GMT",
"version": "v1"
},
{
"created": "Thu, 8 Dec 2011 15:23:38 GMT",
"version": "v2"
}
] | 2016-02-17 | [
[
"Unwin",
"James",
""
]
] | We construct an environmentally selected supersymmetric standard model with a single Higgs doublet, in analogy with the work of Hall and Nomura. The low energy spectrum presents only the standard model states with a single Higgs and TeV scale gauginos. The model features a precise Higgs mass prediction m_H=141\pm 2 GeV and the neutral wino provides a viable dark matter candidate. |
hep-ph/0208121 | Casalbuoni | R. Casalbuoni, E. Fabiano, R. Gatto, M. Mannarelli and G. Nardulli | Phonons and gluons in the crystalline color superconducting phase of QCD | 38 pages, 4 figures | Phys.Rev. D66 (2002) 094006 | 10.1103/PhysRevD.66.094006 | BARI-TH 442/02 | hep-ph cond-mat.supr-con nucl-th | null | The High Density Effective Theory formalism is used to calculate the low
energy properties of the phonons and gluons in the
Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) phase of two-flavor QCD. The effective
phonon Lagrangian for the cubic crystal structure, which is favored according
to a recent study, depends, at the second order in the derivatives, on three
parameters which we calculate in this paper. We also compute for soft momenta
the effective lagrangian for the gluons of the unbroken SU(2)_c group, both for
a single plane wave structure and for the cube. In both cases the Meissner
gluon mass vanishes as in the case of complete isotropy; on the other hand
there is a partial Debye screening due to the existence of blocking regions on
the Fermi spheres. For the single plane wave structure the gluon dielectric
tensor is non isotropic, while it is isotropic for the cubic crystal, in spite
of the intrinsic anisotropy of the structure.
| [
{
"created": "Tue, 13 Aug 2002 07:54:20 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Casalbuoni",
"R.",
""
],
[
"Fabiano",
"E.",
""
],
[
"Gatto",
"R.",
""
],
[
"Mannarelli",
"M.",
""
],
[
"Nardulli",
"G.",
""
]
] | The High Density Effective Theory formalism is used to calculate the low energy properties of the phonons and gluons in the Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) phase of two-flavor QCD. The effective phonon Lagrangian for the cubic crystal structure, which is favored according to a recent study, depends, at the second order in the derivatives, on three parameters which we calculate in this paper. We also compute for soft momenta the effective lagrangian for the gluons of the unbroken SU(2)_c group, both for a single plane wave structure and for the cube. In both cases the Meissner gluon mass vanishes as in the case of complete isotropy; on the other hand there is a partial Debye screening due to the existence of blocking regions on the Fermi spheres. For the single plane wave structure the gluon dielectric tensor is non isotropic, while it is isotropic for the cubic crystal, in spite of the intrinsic anisotropy of the structure. |
hep-ph/0002199 | Alessandro Strumia | Riccardo Barbieri, Paolo Creminelli and Alessandro Strumia | Neutrino oscillations and large extra dimensions | 12 pages, 5 figures. Version 2: misprints fixed, ref.s added,
conclusions modified: at least in minimal models the maximal radius of large
extra dimensions where right-handed neutrinos can propagate must be smaller
than an atom in order to satisfy bounds from the 1987 supernova | Nucl.Phys.B585:28-44,2000 | 10.1016/S0550-3213(00)00348-5 | IFUP-TH/2000-00 and SNS-PH/00-04 | hep-ph | null | Assuming that right-handed neutrinos exist and propagate in some large extra
dimensions, we attempt to give a comprehensive description of the phenomenology
of neutrino oscillations. A few alternative explanations of the atmospheric
neutrino anomaly emerge, different from the standard nuMu --> nuTau or nuMu -->
nuSterile interpretations. Constraints from nucleosynthesis and supernova 1987a
are discussed. The constraints from SN1987a indicates a maximum radius of any
extra dimension of about 1 Angstrom.
| [
{
"created": "Fri, 18 Feb 2000 14:52:48 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Mar 2000 12:25:26 GMT",
"version": "v2"
}
] | 2009-09-01 | [
[
"Barbieri",
"Riccardo",
""
],
[
"Creminelli",
"Paolo",
""
],
[
"Strumia",
"Alessandro",
""
]
] | Assuming that right-handed neutrinos exist and propagate in some large extra dimensions, we attempt to give a comprehensive description of the phenomenology of neutrino oscillations. A few alternative explanations of the atmospheric neutrino anomaly emerge, different from the standard nuMu --> nuTau or nuMu --> nuSterile interpretations. Constraints from nucleosynthesis and supernova 1987a are discussed. The constraints from SN1987a indicates a maximum radius of any extra dimension of about 1 Angstrom. |
1903.10566 | Robert Vertesi | Eszter Frajna, Robert Vertesi | Correlation of heavy and light flavours in simulations | Submitted to MDPI Universe Special Issue "The Zimanyi School and
Analytic Hydrodynamics in High Energy Physics" | Universe 2019, 5(5), 118 | 10.3390/universe5050118 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The ALICE experiment at the Large Hadron Collider (LHC) ring is designed to
study the strongly interacting matter at extreme energy densities created in
high-energy heavy-ion collisions. In this paper we investigate correlations of
heavy and light flavours in simulations at LHC energies at mid-rapidity, with
the primary purpose of proposing experimental application of these methods. Our
studies have shown that investigating the correlation images can aid the
experimental separation of heavy quarks and help understanding the physics that
create them. The shape of the correlation peaks can be used to separate the
electrons stemming from b quarks. This could be a method of identification
that, combined with identification in silicon vertex detectors, may provide
much better sample purity for examining the secondary vertex shift. Based on a
correlation picture it is also possible to distinguish between prompt and late
contributions to D meson yields.
| [
{
"created": "Mon, 25 Mar 2019 19:39:35 GMT",
"version": "v1"
}
] | 2019-05-27 | [
[
"Frajna",
"Eszter",
""
],
[
"Vertesi",
"Robert",
""
]
] | The ALICE experiment at the Large Hadron Collider (LHC) ring is designed to study the strongly interacting matter at extreme energy densities created in high-energy heavy-ion collisions. In this paper we investigate correlations of heavy and light flavours in simulations at LHC energies at mid-rapidity, with the primary purpose of proposing experimental application of these methods. Our studies have shown that investigating the correlation images can aid the experimental separation of heavy quarks and help understanding the physics that create them. The shape of the correlation peaks can be used to separate the electrons stemming from b quarks. This could be a method of identification that, combined with identification in silicon vertex detectors, may provide much better sample purity for examining the secondary vertex shift. Based on a correlation picture it is also possible to distinguish between prompt and late contributions to D meson yields. |
0710.5855 | Feng-Quan Wu | Feng-Quan Wu, Bing-Song Zou | Role of t-channel meson exchange in S-wave pi N and K N scattering | 11 pages, 3 figures | Chinese Physics C (HEP & NP) 32:629-633,2008. | 10.1088/1674-1137/32/8/008 | null | hep-ph | null | The low-energy S-wave pi N and K N scatterings are studied by the K-matrix
approach within the meson exchange framework. The t-channel meson exchanges,
especially rho and sigma exchanges, are found to play a very important role in
these two processes. The t-channel rho exchange determines the isospin
structure of the scattering amplitudes, it gives attractive force in the low
isospin state but repulsive force in the high isospin state. The t-channel
sigma exchange gives a very large contribution in these two processes, while it
is negligible in meson-meson S-wave scatterings.
| [
{
"created": "Wed, 31 Oct 2007 13:08:27 GMT",
"version": "v1"
}
] | 2015-05-13 | [
[
"Wu",
"Feng-Quan",
""
],
[
"Zou",
"Bing-Song",
""
]
] | The low-energy S-wave pi N and K N scatterings are studied by the K-matrix approach within the meson exchange framework. The t-channel meson exchanges, especially rho and sigma exchanges, are found to play a very important role in these two processes. The t-channel rho exchange determines the isospin structure of the scattering amplitudes, it gives attractive force in the low isospin state but repulsive force in the high isospin state. The t-channel sigma exchange gives a very large contribution in these two processes, while it is negligible in meson-meson S-wave scatterings. |
1806.06524 | Qixin Yu | Qi-Xin Yu, Zhen-Yang Wang, Jing-Juan Qi and Xin-Heng Guo | Residues of $\Lambda_Q$-type and $\Sigma_Q$-type Baryons in the
Bethe-Salpeter Equation Approach | null | Phys. Rev. D 98, 036013 (2018) | 10.1103/PhysRevD.98.036013 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the residues of $\Lambda_Q$-type baryons ($\Lambda_Q$ and $\Xi_Q^A$)
$(Q=b,c)$ and $\Sigma_Q$-type baryons ($\Sigma_Q^{(\ast)}$, $\Xi_Q^{S(\ast)}$
and $\Omega_Q^{(\ast)}$) in the quark-diquark model within the Bethe-Salpeter
(BS) formalism. These residues can be used, for example, in the calculations of
the amplitudes in the scattering processes. After constructing the baryonic
currents in the BS formalism, we derive the relations between the BS wave
functions and the residues for these baryons. The BS equations are solved
numerically with the kernel including the scalar confinement and the one gluon
exchange terms and with the covariant instantaneous approximation being
employed in the calculations. Finally, we obtain the numerical values of the
residues $0.103\,\rm GeV\sim0.224\,\rm GeV$ for $\Lambda_Q$, $0.143\,\rm
GeV\sim0.215\,\rm GeV$ for $\Xi_Q^A$, $0.262\,\rm GeV\sim0.361\,\rm GeV$ for
$\Sigma_Q^{(\ast)}$, $0.313\,\rm GeV\sim0.460\,\rm GeV$ for $\Xi_Q^{S(\ast)}$
and $0.473\,\rm GeV\sim0.571\,\rm GeV$ for $\Omega_Q^{(\ast)}$ in the ranges of
the parameters in our model.
| [
{
"created": "Mon, 18 Jun 2018 07:28:14 GMT",
"version": "v1"
}
] | 2018-08-29 | [
[
"Yu",
"Qi-Xin",
""
],
[
"Wang",
"Zhen-Yang",
""
],
[
"Qi",
"Jing-Juan",
""
],
[
"Guo",
"Xin-Heng",
""
]
] | We study the residues of $\Lambda_Q$-type baryons ($\Lambda_Q$ and $\Xi_Q^A$) $(Q=b,c)$ and $\Sigma_Q$-type baryons ($\Sigma_Q^{(\ast)}$, $\Xi_Q^{S(\ast)}$ and $\Omega_Q^{(\ast)}$) in the quark-diquark model within the Bethe-Salpeter (BS) formalism. These residues can be used, for example, in the calculations of the amplitudes in the scattering processes. After constructing the baryonic currents in the BS formalism, we derive the relations between the BS wave functions and the residues for these baryons. The BS equations are solved numerically with the kernel including the scalar confinement and the one gluon exchange terms and with the covariant instantaneous approximation being employed in the calculations. Finally, we obtain the numerical values of the residues $0.103\,\rm GeV\sim0.224\,\rm GeV$ for $\Lambda_Q$, $0.143\,\rm GeV\sim0.215\,\rm GeV$ for $\Xi_Q^A$, $0.262\,\rm GeV\sim0.361\,\rm GeV$ for $\Sigma_Q^{(\ast)}$, $0.313\,\rm GeV\sim0.460\,\rm GeV$ for $\Xi_Q^{S(\ast)}$ and $0.473\,\rm GeV\sim0.571\,\rm GeV$ for $\Omega_Q^{(\ast)}$ in the ranges of the parameters in our model. |
hep-ph/0008211 | Gail C. McLaughlin | G. C. McLaughlin | Active-Sterile Neutrino Transformation and r-Process Nucleosynthesis | 5 pages including 2 figures, to appear in the Proceedings of the
Conference on the Intersections of Nuclear and Particle Physics 2000 | AIP Conf.Proc. 549 (2002) 800-804 | 10.1063/1.1345369 | null | hep-ph | null | The type II supernova is considered as a candidate site for the production of
heavy elements. Since the supernova produces an intense neutrino flux, neutrino
scattering processes will impact element formation. We examine active-sterile
neutrino conversion in this environment and find that it may help to produce
the requisite neutron-to-seed ratio for synthesis of the r-process elements.
| [
{
"created": "Fri, 18 Aug 2000 23:40:38 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"McLaughlin",
"G. C.",
""
]
] | The type II supernova is considered as a candidate site for the production of heavy elements. Since the supernova produces an intense neutrino flux, neutrino scattering processes will impact element formation. We examine active-sterile neutrino conversion in this environment and find that it may help to produce the requisite neutron-to-seed ratio for synthesis of the r-process elements. |
2312.00982 | Douglas Tuckler | David McKeen, John N. Ng, Douglas Tuckler | Higgs Portal Interpretation of the Belle II $B^+ \to K^+ \nu \nu$
Measurement | 13 pages, 4 figures, 1 appendix | null | null | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | The Belle II experiment recently observed the decay $B^+ \to K^+ \nu \nu$ for
the first time, with a measured value for the branching ratio of $ (2.3 \pm
0.7) \times 10^{-5}$. This result exhibits a $\sim 3\sigma$ deviation from the
Standard Model (SM) prediction. The observed enhancement with respect to the
Standard Model could indicate the presence of invisible light new physics. In
this paper, we investigate whether this result can be accommodated in a minimal
Higgs portal model, where the SM is extended by a singlet Higgs scalar that
decays invisibly to dark sector states. We find that current and future bounds
on invisible decays of the 125 GeV Higgs boson completely exclude a new scalar
with a mass $\gtrsim 10$ GeV. On the other hand, the Belle II results can be
successfully accommodated if the new scalar is lighter than $B$ mesons but
heavier than kaons. We also investigate the cosmological implications of the
new states and explore the possibility that they are part of an abelian Higgs
extension of the SM. Future Higgs factories are expected to place stringent
bounds on the invisible branching ratio of the 125 GeV Higgs boson, and will be
able to definitively test the region of parameter space favored by the Belle II
results.
| [
{
"created": "Sat, 2 Dec 2023 00:38:57 GMT",
"version": "v1"
}
] | 2023-12-05 | [
[
"McKeen",
"David",
""
],
[
"Ng",
"John N.",
""
],
[
"Tuckler",
"Douglas",
""
]
] | The Belle II experiment recently observed the decay $B^+ \to K^+ \nu \nu$ for the first time, with a measured value for the branching ratio of $ (2.3 \pm 0.7) \times 10^{-5}$. This result exhibits a $\sim 3\sigma$ deviation from the Standard Model (SM) prediction. The observed enhancement with respect to the Standard Model could indicate the presence of invisible light new physics. In this paper, we investigate whether this result can be accommodated in a minimal Higgs portal model, where the SM is extended by a singlet Higgs scalar that decays invisibly to dark sector states. We find that current and future bounds on invisible decays of the 125 GeV Higgs boson completely exclude a new scalar with a mass $\gtrsim 10$ GeV. On the other hand, the Belle II results can be successfully accommodated if the new scalar is lighter than $B$ mesons but heavier than kaons. We also investigate the cosmological implications of the new states and explore the possibility that they are part of an abelian Higgs extension of the SM. Future Higgs factories are expected to place stringent bounds on the invisible branching ratio of the 125 GeV Higgs boson, and will be able to definitively test the region of parameter space favored by the Belle II results. |
hep-ph/9709510 | Nicholas Tracas | G. K. Leontaris, N. D. Tracas | Modular Weights, U(1)'s and Mass Matrices | LaTex file, 11 pages, 1 Figure.Typos corrected and a reference has
been added. Accepted in Phys. Lett. B | Phys.Lett. B419 (1998) 206-210 | 10.1016/S0370-2693(97)01412-3 | null | hep-ph | null | We derive the scalar mass matrices in effective supergravity models augmented
by a $U(1)_F$ family symmetry. Simple relations between $U(1)_F$ charges and
modular weights of the superfields are derived and used to express the matrices
with a minimum number of parameters. The model predicts a branching ratio for
the $\mu\to e\gamma$ process close to the present experimental limits.
| [
{
"created": "Tue, 30 Sep 1997 17:14:28 GMT",
"version": "v1"
},
{
"created": "Thu, 6 Nov 1997 13:40:36 GMT",
"version": "v2"
}
] | 2009-10-30 | [
[
"Leontaris",
"G. K.",
""
],
[
"Tracas",
"N. D.",
""
]
] | We derive the scalar mass matrices in effective supergravity models augmented by a $U(1)_F$ family symmetry. Simple relations between $U(1)_F$ charges and modular weights of the superfields are derived and used to express the matrices with a minimum number of parameters. The model predicts a branching ratio for the $\mu\to e\gamma$ process close to the present experimental limits. |
1904.09832 | Maryam Soleymaninia | Maral Salajegheh, S. Mohammad Moosavi Nejad, Maryam Soleymaninia,
Hamzeh Khanpour and S. Atashbar Tehrani | NNLO charmed-meson fragmentation functions and their uncertainties in
the presence of meson mass corrections | 12 pages, 6 figures, 6 Tables, Accepted for Publication in European
Physical Journal C | The European Physical Journal C 2019 | 10.1140/epjc/s10052-019-7521-x | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The main aim of this paper is to present new sets of non-perturbative
fragmentation functions (FFs) for $D^0$ and $D^+$ mesons at next-to-leading
(NLO) and, for the first time, at next-to-next-to-leading order (NNLO) in the
$\overline{\mathrm{MS}}$ factorization scheme with five massless quark flavors.
This new determination of FFs is based on the QCD fit to the {\tt OPAL}
experimental data for hadron production in the electron-positron
single-inclusive annihilation (SIA). We discuss in detail the novel aspects of
the methodology used in our analysis and the validity of obtained FFs by
comparing with previous works in literature which have been carried out up to
NLO accuracy. We will also incorporate the effect of charmed meson mass
corrections into our QCD analysis and discuss the improvements upon inclusion
of these effects. The uncertainties in the extracted FFs as well as in the
corresponding observables are estimated using the "Hessian" approach. For a
typical application, we use our new FFs to make theoretical predictions for the
energy distributions of charmed mesons inclusively produced through the decay
of unpolarized top quarks, to be measured at the CERN LHC. As a result of this
analysis, suggestions are discussed for possible future studies on the current
topic to consider any theory improvements and other available experimental
observables.
| [
{
"created": "Mon, 22 Apr 2019 12:49:30 GMT",
"version": "v1"
},
{
"created": "Sat, 30 Nov 2019 09:49:16 GMT",
"version": "v2"
}
] | 2019-12-17 | [
[
"Salajegheh",
"Maral",
""
],
[
"Nejad",
"S. Mohammad Moosavi",
""
],
[
"Soleymaninia",
"Maryam",
""
],
[
"Khanpour",
"Hamzeh",
""
],
[
"Tehrani",
"S. Atashbar",
""
]
] | The main aim of this paper is to present new sets of non-perturbative fragmentation functions (FFs) for $D^0$ and $D^+$ mesons at next-to-leading (NLO) and, for the first time, at next-to-next-to-leading order (NNLO) in the $\overline{\mathrm{MS}}$ factorization scheme with five massless quark flavors. This new determination of FFs is based on the QCD fit to the {\tt OPAL} experimental data for hadron production in the electron-positron single-inclusive annihilation (SIA). We discuss in detail the novel aspects of the methodology used in our analysis and the validity of obtained FFs by comparing with previous works in literature which have been carried out up to NLO accuracy. We will also incorporate the effect of charmed meson mass corrections into our QCD analysis and discuss the improvements upon inclusion of these effects. The uncertainties in the extracted FFs as well as in the corresponding observables are estimated using the "Hessian" approach. For a typical application, we use our new FFs to make theoretical predictions for the energy distributions of charmed mesons inclusively produced through the decay of unpolarized top quarks, to be measured at the CERN LHC. As a result of this analysis, suggestions are discussed for possible future studies on the current topic to consider any theory improvements and other available experimental observables. |
hep-ph/9604406 | null | Howard Baer, Chih-hao Chen, Frank Paige and Xerxes tata | Supersymmetry Reach of Tevatron Upgrades: A Comparative Study | 31 pages including 13 figures; uuencoded tex file with EPS figures
available from ftp://hep.fsu.edu/preprints/baer/tev33.uu | Phys.Rev.D54:5866-5879,1996 | 10.1103/PhysRevD.54.5866 | FSU-HEP-960415, UCD-96-11, UH-511-847-96 | hep-ph | null | We use ISAJET to perform a detailed comparison of the supersymmetry reach of
the current Tevatron (100~pb$^{-1}$) with that of the Main Injector
(2~fb$^{-1}$) and the proposed TeV33 upgrade designed to yield an integrated
luminosity of 25~fb$^{-1}$. Our analysis is performed within the framework of
the minimal supergravity model with gauge coupling unification and radiative
electroweak symmetry breaking. For each of these three luminosity options, we
delineate the regions of parameter space where jets plus missing energy plus 0,
1, 2 (opposite sign and same-sign dileptons), and 3 isolated lepton signals
from the cascade decays of sparticles should be visible above standard model
backgrounds. We compare these with the parameter regions where signals in the
clean isolated dilepton and trilepton channels (from chargino/neutralino and
slepton production) should be observable.
| [
{
"created": "Thu, 25 Apr 1996 22:23:56 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Baer",
"Howard",
""
],
[
"Chen",
"Chih-hao",
""
],
[
"Paige",
"Frank",
""
],
[
"tata",
"Xerxes",
""
]
] | We use ISAJET to perform a detailed comparison of the supersymmetry reach of the current Tevatron (100~pb$^{-1}$) with that of the Main Injector (2~fb$^{-1}$) and the proposed TeV33 upgrade designed to yield an integrated luminosity of 25~fb$^{-1}$. Our analysis is performed within the framework of the minimal supergravity model with gauge coupling unification and radiative electroweak symmetry breaking. For each of these three luminosity options, we delineate the regions of parameter space where jets plus missing energy plus 0, 1, 2 (opposite sign and same-sign dileptons), and 3 isolated lepton signals from the cascade decays of sparticles should be visible above standard model backgrounds. We compare these with the parameter regions where signals in the clean isolated dilepton and trilepton channels (from chargino/neutralino and slepton production) should be observable. |
1010.2584 | Heidi Kuismanen | Heidi Kuismanen. Jukka Maalampi, Iiro Vilja | Numerical study of leptogenesis in a 5D split fermion model with bulk
neutrinos | 15 pages, 4 figures, accepted for publication in Phys. Rev. D | Phys.Rev.D83:053005,2011 | 10.1103/PhysRevD.83.053005 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study numerically a 5D hybrid model which incorporates a split fermion
scenario and bulk neutrinos. We perform a Monte Carlo analysis of the model in
order to find the regions in the parameter space allowing for realization of
the leptogenesis. We find that higher order Yukawa terms must be included in
order the model to produce a CP violation and net baryon number sufficient for
the creation of the observed baryon asymmetry of the Universe.
| [
{
"created": "Wed, 13 Oct 2010 07:06:28 GMT",
"version": "v1"
},
{
"created": "Fri, 18 Feb 2011 07:43:07 GMT",
"version": "v2"
},
{
"created": "Fri, 11 Mar 2011 07:18:06 GMT",
"version": "v3"
}
] | 2015-03-17 | [
[
"Maalampi",
"Heidi Kuismanen. Jukka",
""
],
[
"Vilja",
"Iiro",
""
]
] | We study numerically a 5D hybrid model which incorporates a split fermion scenario and bulk neutrinos. We perform a Monte Carlo analysis of the model in order to find the regions in the parameter space allowing for realization of the leptogenesis. We find that higher order Yukawa terms must be included in order the model to produce a CP violation and net baryon number sufficient for the creation of the observed baryon asymmetry of the Universe. |
1607.06234 | Mikhail Zubkov Dr | Z.V.Khaidukov, M.A.Zubkov | Modified top quark condensation model with the extra heavy fermion, the
$125$ GeV Pseudo - Goldstone boson, and the additional heavy scalar bosons | Latex, 20 pages | Int. J. Mod. Phys. A 32, 1750141 (2017) | 10.1142/S0217751X1750141X | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the modified top quark condensation model proposed in
\cite{VZ2015}. This construction was inspired by the top - seesaw scenario, in
which the extra heavy fermion $\chi$ is added that may be paired with the top
quark. Besides, this model incorporates the ideas of the Little Higgs scenario,
in which the $125$ GeV scalar particle appears as a Pseudo - Goldstone boson.
This model admits (in addition to the $125$ GeV scalar boson $H$) the heavier
scalar excitation $H^\prime$. We consider the region of parameters, where its
mass is $M_{H^\prime} \sim 1$ TeV, the width of $H^\prime$ is
$\Gamma_{H^\prime} \sim 0.3 M_{H^\prime}$, while the mass of the heavy fermion
is $m_\chi \sim 1$ TeV. We find that in this model the value of the cross -
section $\sigma_{pp \to H^\prime + X \to \gamma+\gamma + X}$ for $\sqrt{s}=13$
TeV is essentially smaller than the present experimental upper bound. Besides,
we find, that for the chosen values of parameters there should exist the CP -
even scalar boson with mass $\approx 2 m_\chi$ and very small width. In
addition, the model predicts the existence of the extra neutral CP even scalar
boson and the charged scalar boson with masses of the order of $1$ TeV.
| [
{
"created": "Thu, 21 Jul 2016 08:51:39 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Aug 2016 19:37:44 GMT",
"version": "v2"
},
{
"created": "Sat, 26 Aug 2017 20:15:54 GMT",
"version": "v3"
}
] | 2017-08-29 | [
[
"Khaidukov",
"Z. V.",
""
],
[
"Zubkov",
"M. A.",
""
]
] | We discuss the modified top quark condensation model proposed in \cite{VZ2015}. This construction was inspired by the top - seesaw scenario, in which the extra heavy fermion $\chi$ is added that may be paired with the top quark. Besides, this model incorporates the ideas of the Little Higgs scenario, in which the $125$ GeV scalar particle appears as a Pseudo - Goldstone boson. This model admits (in addition to the $125$ GeV scalar boson $H$) the heavier scalar excitation $H^\prime$. We consider the region of parameters, where its mass is $M_{H^\prime} \sim 1$ TeV, the width of $H^\prime$ is $\Gamma_{H^\prime} \sim 0.3 M_{H^\prime}$, while the mass of the heavy fermion is $m_\chi \sim 1$ TeV. We find that in this model the value of the cross - section $\sigma_{pp \to H^\prime + X \to \gamma+\gamma + X}$ for $\sqrt{s}=13$ TeV is essentially smaller than the present experimental upper bound. Besides, we find, that for the chosen values of parameters there should exist the CP - even scalar boson with mass $\approx 2 m_\chi$ and very small width. In addition, the model predicts the existence of the extra neutral CP even scalar boson and the charged scalar boson with masses of the order of $1$ TeV. |
hep-ph/0109078 | Zvi Bern | Z. Bern, A. De Freitas, L. Dixon | Two-Loop Amplitudes for Gluon Fusion into Two Photons | 24 pages, JHEP style | JHEP 0109:037,2001 | 10.1088/1126-6708/2001/09/037 | SLAC-PUB-8976, UCLA/01/TEP/16 | hep-ph | null | We present the two-loop matrix elements for the scattering of two gluons into
two photons in QCD. These matrix elements will enter into improved estimates of
the QCD background to Higgs production at the LHC when the Higgs decays into
two photons. The photon mode is especially important if M_H < 140 GeV. We also
give the amplitudes for the crossed process, glue gamma to glue gamma.
| [
{
"created": "Mon, 10 Sep 2001 15:30:42 GMT",
"version": "v1"
}
] | 2010-02-03 | [
[
"Bern",
"Z.",
""
],
[
"De Freitas",
"A.",
""
],
[
"Dixon",
"L.",
""
]
] | We present the two-loop matrix elements for the scattering of two gluons into two photons in QCD. These matrix elements will enter into improved estimates of the QCD background to Higgs production at the LHC when the Higgs decays into two photons. The photon mode is especially important if M_H < 140 GeV. We also give the amplitudes for the crossed process, glue gamma to glue gamma. |
1107.1080 | Andrea Beraudo | A. Beraudo, J.G. Milhano and U.A. Wiedemann | Suppression of high-pT particle production in AA collisions: the role of
in-medium color-flow | Talk given at the conference Quark Matter 2011 | null | 10.1088/0954-3899/38/12/124118 | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The suppression of high-pT single-hadron spectra in heavy-ion collisions is
usually interpreted as due to parton energy-loss of high-momentum quarks and
gluons propagating in the plasma. Here, we discuss to what extent this partonic
picture must be complemented by a picture of medium-modified hadronization. In
particular, we show how color-exchange with the medium modifies the properties
of color singlet-clusters arising from the parton branchings, producing a
softening of the hadron spectra.
| [
{
"created": "Wed, 6 Jul 2011 10:01:29 GMT",
"version": "v1"
}
] | 2015-05-28 | [
[
"Beraudo",
"A.",
""
],
[
"Milhano",
"J. G.",
""
],
[
"Wiedemann",
"U. A.",
""
]
] | The suppression of high-pT single-hadron spectra in heavy-ion collisions is usually interpreted as due to parton energy-loss of high-momentum quarks and gluons propagating in the plasma. Here, we discuss to what extent this partonic picture must be complemented by a picture of medium-modified hadronization. In particular, we show how color-exchange with the medium modifies the properties of color singlet-clusters arising from the parton branchings, producing a softening of the hadron spectra. |
1707.03646 | Kai Schmitz | Keisuke Harigaya, Kai Schmitz | Unified Model of Chaotic Inflation and Dynamical Supersymmetry Breaking | 6 pages, 1 figure | null | 10.1016/j.physletb.2017.08.050 | null | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The large hierarchy between the Planck scale and the weak scale can be
explained by the dynamical breaking of supersymmetry in strongly coupled gauge
theories. Similarly, the hierarchy between the Planck scale and the energy
scale of inflation may also originate from strong dynamics, which dynamically
generate the inflaton potential. We present a model of the hidden sector which
unifies these two ideas, i.e., in which the scales of inflation and
supersymmetry breaking are provided by the dynamics of the same gauge group.
The resultant inflation model is chaotic inflation with a fractional power-law
potential in accord with the upper bound on the tensor-to-scalar ratio. The
supersymmetry breaking scale can be much smaller than the inflation scale, so
that the solution to the large hierarchy problem of the weak scale remains
intact. As an intrinsic feature of our model, we find that the sgoldstino,
which might disturb the inflationary dynamics, is automatically stabilized
during inflation by dynamically generated corrections in the strongly coupled
sector. This renders our model a field-theoretical realization of what is
sometimes referred to as sgoldstino-less inflation.
| [
{
"created": "Wed, 12 Jul 2017 11:14:28 GMT",
"version": "v1"
}
] | 2017-11-22 | [
[
"Harigaya",
"Keisuke",
""
],
[
"Schmitz",
"Kai",
""
]
] | The large hierarchy between the Planck scale and the weak scale can be explained by the dynamical breaking of supersymmetry in strongly coupled gauge theories. Similarly, the hierarchy between the Planck scale and the energy scale of inflation may also originate from strong dynamics, which dynamically generate the inflaton potential. We present a model of the hidden sector which unifies these two ideas, i.e., in which the scales of inflation and supersymmetry breaking are provided by the dynamics of the same gauge group. The resultant inflation model is chaotic inflation with a fractional power-law potential in accord with the upper bound on the tensor-to-scalar ratio. The supersymmetry breaking scale can be much smaller than the inflation scale, so that the solution to the large hierarchy problem of the weak scale remains intact. As an intrinsic feature of our model, we find that the sgoldstino, which might disturb the inflationary dynamics, is automatically stabilized during inflation by dynamically generated corrections in the strongly coupled sector. This renders our model a field-theoretical realization of what is sometimes referred to as sgoldstino-less inflation. |
2201.08771 | Eugenio Megias | Eugenio Megias, Evandro Andrade II, Airton Deppman, Arnaldo Gammal,
Debora P. Menezes, Tiago Nunes da Silva, Varese S. Tim\'oteo | Tsallis statistics and thermofractals: applications to high energy and
hadron physics | 16 pages, 8 figures. Talk given by E.Megias at the 10th International
Conference on New Frontiers in Physics (ICNFP 2021), 23 Aug - 7 Oct 2021,
Kolymbari, Crete, Greece | null | null | null | hep-ph cond-mat.quant-gas nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the applications of non-extensive Tsallis statistics to high energy
and hadron physics. These applications include studies of $pp$ collisions,
equation of state of QCD, as well as Bose-Einstein condensation. We also
analyze the connections of Tsallis statistics with thermofractals, and address
some of the conceptual aspects of the fractal approach, which are expressed in
terms of the renormalization group equation and the self-energy corrections to
the parton mass. We associate these well-known concepts with the origins of the
fractal structure in the quantum field theory.
| [
{
"created": "Fri, 21 Jan 2022 16:39:17 GMT",
"version": "v1"
}
] | 2022-01-24 | [
[
"Megias",
"Eugenio",
""
],
[
"Andrade",
"Evandro",
"II"
],
[
"Deppman",
"Airton",
""
],
[
"Gammal",
"Arnaldo",
""
],
[
"Menezes",
"Debora P.",
""
],
[
"da Silva",
"Tiago Nunes",
""
],
[
"Timóteo",
"Varese S.",
... | We study the applications of non-extensive Tsallis statistics to high energy and hadron physics. These applications include studies of $pp$ collisions, equation of state of QCD, as well as Bose-Einstein condensation. We also analyze the connections of Tsallis statistics with thermofractals, and address some of the conceptual aspects of the fractal approach, which are expressed in terms of the renormalization group equation and the self-energy corrections to the parton mass. We associate these well-known concepts with the origins of the fractal structure in the quantum field theory. |
0910.1334 | Stephen Godfrey | Ross Diener, Stephen Godfrey and Travis A. W. Martin (Carleton
University and TRIUMF) | Discovery and Identification of Extra Neutral Gauge Bosons at the LHC | 6 pages, 6 figures, To be published in the proceedings of DPF-2009,
Detroit, MI, July 2009, eConf C090726 | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present the discovery prospects for a Z' resonance and some expected
results for Z' diagnostic measurements at the LHC. The discovery reach is
highly dependent on the energy and luminosities that may be attained at the
LHC, and a number of energy and integrated luminosity scenarios are presented.
In addition, the use of third generation quark final states for distinguishing
between models and for measuring a forward-backward asymmetry is explored.
| [
{
"created": "Wed, 7 Oct 2009 19:21:16 GMT",
"version": "v1"
}
] | 2009-10-10 | [
[
"Diener",
"Ross",
"",
"Carleton\n University and TRIUMF"
],
[
"Godfrey",
"Stephen",
"",
"Carleton\n University and TRIUMF"
],
[
"Martin",
"Travis A. W.",
"",
"Carleton\n University and TRIUMF"
]
] | We present the discovery prospects for a Z' resonance and some expected results for Z' diagnostic measurements at the LHC. The discovery reach is highly dependent on the energy and luminosities that may be attained at the LHC, and a number of energy and integrated luminosity scenarios are presented. In addition, the use of third generation quark final states for distinguishing between models and for measuring a forward-backward asymmetry is explored. |
hep-ph/0101048 | Andre Gusso | E. M. Gregores (Madison, U. of Winsconsin), A. Gusso (Valencia U.), S.
F. Novaes (Sao Paulo, IFT) | New Limits on Doubly Charged Bileptons from CERN LEP Data and the Search
at Future Electron-Positron and Electron-Photon Colliders | Revised version with 14 pages, 7 figures, RevTex. To appear in Phys.
Rev. D | Phys.Rev. D64 (2001) 015004 | 10.1103/PhysRevD.64.015004 | IFT-P.097/2000, IFIC/00-84, MADPH-00-1209 | hep-ph | null | We show that the accumulated LEP-II data taken at $\sqrt{s} =$ 130 to 206 GeV
can establish more restrictive bounds on doubly charged bileptons couplings and
masses than any other experiment so far. We also analyze the discovery
potential of a prospective linear collider operating in both $e^+ e^-$ and $e
\gamma$ modes.
| [
{
"created": "Fri, 5 Jan 2001 12:11:47 GMT",
"version": "v1"
},
{
"created": "Thu, 31 May 2001 11:46:01 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Gregores",
"E. M.",
"",
"Madison, U. of Winsconsin"
],
[
"Gusso",
"A.",
"",
"Valencia U."
],
[
"Novaes",
"S. F.",
"",
"Sao Paulo, IFT"
]
] | We show that the accumulated LEP-II data taken at $\sqrt{s} =$ 130 to 206 GeV can establish more restrictive bounds on doubly charged bileptons couplings and masses than any other experiment so far. We also analyze the discovery potential of a prospective linear collider operating in both $e^+ e^-$ and $e \gamma$ modes. |
1511.01811 | Pedro Simoni Pasquini | P. S. Pasquini, O. L. G. Peres | Bounds on Neutrino-Scalar Yukawa Coupling | 8 pages, 7 figures | Phys. Rev. D 93, 053007 (2016) | 10.1103/PhysRevD.93.053007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | General neutrino-scalar couplings appear in many extensions of Standard
Model. We can probe these neutrino-scalar couplings by leptonic decay of mesons
and from heavy neutrino search. Our analysis improves the present limits to
$|g_e|^2<1.9\times 10^{-6}$ and $|g_\mu|^2<1.9\times 10^{-7}$ at 90\% C.L. for
massless scalars. For massive scalars we found for the first time the
constraints for $g^2_{\alpha}$ couplings to be $10^{-6}-10^{-1}$ respectively
for scalar masses between below 1 MeV and for 300 MeV.
| [
{
"created": "Thu, 5 Nov 2015 16:48:33 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Feb 2016 21:21:45 GMT",
"version": "v2"
}
] | 2016-03-23 | [
[
"Pasquini",
"P. S.",
""
],
[
"Peres",
"O. L. G.",
""
]
] | General neutrino-scalar couplings appear in many extensions of Standard Model. We can probe these neutrino-scalar couplings by leptonic decay of mesons and from heavy neutrino search. Our analysis improves the present limits to $|g_e|^2<1.9\times 10^{-6}$ and $|g_\mu|^2<1.9\times 10^{-7}$ at 90\% C.L. for massless scalars. For massive scalars we found for the first time the constraints for $g^2_{\alpha}$ couplings to be $10^{-6}-10^{-1}$ respectively for scalar masses between below 1 MeV and for 300 MeV. |
hep-ph/0010255 | Stephen C. Davis | Stephen C. Davis | Brane World Linearized Cosmic String Gravity | 9 pages, 1 figure | Phys.Lett. B499 (2001) 179-186 | 10.1016/S0370-2693(01)00020-X | SWAT/269 | hep-ph astro-ph | null | The gravitational properties of cosmic strings in the Randall-Sundrum brane
world scenario are investigated. Using a gauge in which the brane remains
straight, the leading order corrections to the metric on the brane are
determined. In contrast to their non-brane equivalents, these strings have an
attractive 1/r^2 potential and a radially dependent deficit angle. These two
effects alter many cosmological properties of the string, such as the formation
of double images. As a result of the attractive force the string will collect
matter as it moves through space.
| [
{
"created": "Sat, 21 Oct 2000 17:23:09 GMT",
"version": "v1"
},
{
"created": "Thu, 14 Dec 2000 15:55:03 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Davis",
"Stephen C.",
""
]
] | The gravitational properties of cosmic strings in the Randall-Sundrum brane world scenario are investigated. Using a gauge in which the brane remains straight, the leading order corrections to the metric on the brane are determined. In contrast to their non-brane equivalents, these strings have an attractive 1/r^2 potential and a radially dependent deficit angle. These two effects alter many cosmological properties of the string, such as the formation of double images. As a result of the attractive force the string will collect matter as it moves through space. |
hep-ph/0401064 | Oscar Vives | Graham G. Ross (U. Oxford), Liliana Velasco-Sevilla (U. Michigan) and
Oscar Vives (U. Valencia) | Spontaneous CP violation and Non-Abelian Family Symmetry in SUSY | 31 pages, 2 figures. Several typos and notation inconsistencies
corrected. Discusion of vacuum alignment improved and a mistake in the
calculation of the transformations to canonical Kahler removed. Physical
results completely unchanged. Accepted version for publication in Nucl. Phys.
B | Nucl.Phys. B692 (2004) 50-82 | 10.1016/j.nuclphysb.2004.05.020 | OUTP-0402P, MCTP-03-61, FTUV-04-0110 | hep-ph | null | We analyse the properties of generic models based on an SU(3) family symmetry
providing a full description of quark charged lepton and neutrino masses and
mixing angles. We show that a precise fit of the resulting fermion textures is
consistent with CP being spontaneously broken in the flavour sector. The CP
violating phases are determined by the scalar potential and we discuss how
symmetries readily lead to a maximal phase controlling CP violation in the
quark sector. In a specific model the CP violation to be expected in the
neutrino sector is related to that in the quark sector and we determine this
relation for two viable models. In addition to giving rise to the observed
structure of quark and lepton masses this class of model solves both the CP and
flavour problems normally associated with supersymmetric models. The flavour
structure of the soft supersymmetry breaking terms is controlled by the family
symmetry and we analyse some of the related phenomenological implications.
| [
{
"created": "Mon, 12 Jan 2004 18:30:28 GMT",
"version": "v1"
},
{
"created": "Tue, 11 May 2004 12:54:11 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Ross",
"Graham G.",
"",
"U. Oxford"
],
[
"Velasco-Sevilla",
"Liliana",
"",
"U. Michigan"
],
[
"Vives",
"Oscar",
"",
"U. Valencia"
]
] | We analyse the properties of generic models based on an SU(3) family symmetry providing a full description of quark charged lepton and neutrino masses and mixing angles. We show that a precise fit of the resulting fermion textures is consistent with CP being spontaneously broken in the flavour sector. The CP violating phases are determined by the scalar potential and we discuss how symmetries readily lead to a maximal phase controlling CP violation in the quark sector. In a specific model the CP violation to be expected in the neutrino sector is related to that in the quark sector and we determine this relation for two viable models. In addition to giving rise to the observed structure of quark and lepton masses this class of model solves both the CP and flavour problems normally associated with supersymmetric models. The flavour structure of the soft supersymmetry breaking terms is controlled by the family symmetry and we analyse some of the related phenomenological implications. |
1504.03333 | Yonatan Kahn | Adam J. Anderson, Patrick J. Fox, Yonatan Kahn, Matthew McCullough | Halo-Independent Direct Detection Analyses Without Mass Assumptions | 23 pages, 8 figures. v2: footnote and references added | null | 10.1088/1475-7516/2015/10/012 | CERN-PH-TH-2015-073, FERMILAB-PUB-15-096-T, MIT-CTP/4661 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Results from direct detection experiments are typically interpreted by
employing an assumption about the dark matter velocity distribution, with
results presented in the $m_\chi-\sigma_n$ plane. Recently methods which are
independent of the DM halo velocity distribution have been developed which
present results in the $v_{min}-\tilde{g}$ plane, but these in turn require an
assumption on the dark matter mass. Here we present an extension of these
halo-independent methods for dark matter direct detection which does not
require a fiducial choice of the dark matter mass. With a change of variables
from $v_{min}$ to nuclear recoil momentum ($p_R$), the full halo-independent
content of an experimental result for any dark matter mass can be condensed
into a single plot as a function of a new halo integral variable, which we call
$\tilde{h}(p_R)$. The entire family of conventional halo-independent
$\tilde{g}(v_{min})$ plots for all DM masses are directly found from the single
$\tilde{h}(p_R)$ plot through a simple rescaling of axes. By considering
results in $\tilde{h}(p_R)$ space, one can determine if two experiments are
inconsistent for all masses and all physically possible halos, or for what
range of dark matter masses the results are inconsistent for all halos, without
the necessity of multiple $\tilde{g}(v_{min})$ plots for different DM masses.
We conduct a sample analysis comparing the CDMS II Si events to the null
results from LUX, XENON10, and SuperCDMS using our method and discuss how the
mass-independent limits can be strengthened by imposing the physically
reasonable requirement of a finite halo escape velocity.
| [
{
"created": "Mon, 13 Apr 2015 20:01:03 GMT",
"version": "v1"
},
{
"created": "Tue, 12 May 2015 17:17:24 GMT",
"version": "v2"
}
] | 2015-10-14 | [
[
"Anderson",
"Adam J.",
""
],
[
"Fox",
"Patrick J.",
""
],
[
"Kahn",
"Yonatan",
""
],
[
"McCullough",
"Matthew",
""
]
] | Results from direct detection experiments are typically interpreted by employing an assumption about the dark matter velocity distribution, with results presented in the $m_\chi-\sigma_n$ plane. Recently methods which are independent of the DM halo velocity distribution have been developed which present results in the $v_{min}-\tilde{g}$ plane, but these in turn require an assumption on the dark matter mass. Here we present an extension of these halo-independent methods for dark matter direct detection which does not require a fiducial choice of the dark matter mass. With a change of variables from $v_{min}$ to nuclear recoil momentum ($p_R$), the full halo-independent content of an experimental result for any dark matter mass can be condensed into a single plot as a function of a new halo integral variable, which we call $\tilde{h}(p_R)$. The entire family of conventional halo-independent $\tilde{g}(v_{min})$ plots for all DM masses are directly found from the single $\tilde{h}(p_R)$ plot through a simple rescaling of axes. By considering results in $\tilde{h}(p_R)$ space, one can determine if two experiments are inconsistent for all masses and all physically possible halos, or for what range of dark matter masses the results are inconsistent for all halos, without the necessity of multiple $\tilde{g}(v_{min})$ plots for different DM masses. We conduct a sample analysis comparing the CDMS II Si events to the null results from LUX, XENON10, and SuperCDMS using our method and discuss how the mass-independent limits can be strengthened by imposing the physically reasonable requirement of a finite halo escape velocity. |
0709.0476 | Alexander Kovner | Tolga Altinoluk, Alex Kovner and Javier Peressutti (University of
Connecticut) | Eikonal but not: a complementary view of high energy evolution | 5 pages | Phys.Lett.B659:144-148,2008 | 10.1016/j.physletb.2007.11.011 | null | hep-ph | null | The high energy evolution equations that describe the evolution of hadronic
amplitudes with energy are derived assuming eikonal interaction of the evolved
hadronic wave function with the target. In this note we remark that this
derivation allows a different interpretation, whereby the hadronic wave
function is not evolved, but instead the evolution acts on the S - matrix
operator. In this approach, analogous to the Heisenberg picture of Quantum
mechanics, the scattering is not eikonal and additional boost provides for
radiation of more gluons in the final state.
| [
{
"created": "Tue, 4 Sep 2007 16:31:18 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Altinoluk",
"Tolga",
"",
"University of\n Connecticut"
],
[
"Kovner",
"Alex",
"",
"University of\n Connecticut"
],
[
"Peressutti",
"Javier",
"",
"University of\n Connecticut"
]
] | The high energy evolution equations that describe the evolution of hadronic amplitudes with energy are derived assuming eikonal interaction of the evolved hadronic wave function with the target. In this note we remark that this derivation allows a different interpretation, whereby the hadronic wave function is not evolved, but instead the evolution acts on the S - matrix operator. In this approach, analogous to the Heisenberg picture of Quantum mechanics, the scattering is not eikonal and additional boost provides for radiation of more gluons in the final state. |
2311.09688 | Igor Reis | Igor Reis, Emmanuel Moulin and Aion Viana | Sensitivity to keV-MeV dark matter from cosmic-ray scattering with
current and the upcoming ground-based arrays CTA and SWGO | Presented at the 38th International Cosmic Ray Conference (ICRC
2023), 2023 (arXiv:submit/5238756) | null | null | CTA-ICRC/2023/36 | hep-ph astro-ph.HE | http://creativecommons.org/licenses/by/4.0/ | A wealth of astrophysical and cosmological observational evidence shows that
the matter content of the universe is made of about 85$\%$ of non-baryonic dark
matter. Huge experimental efforts have been deployed to look for the direct
detection of dark matter via their scattering on target nucleons, their
production in colliders, and their indirect detection via their annihilation
products. Inelastic scattering of high-energy cosmic rays off dark matter
particles populating the Milky Way halo would produce secondary gamma rays in
the final state from the decay of the neutral pions produced in such
interactions, providing a new avenue to probe dark matter properties. We
compute here the sensitivity for H.E.S.S.-like observatory, a
current-generation ground-based Cherenkov telescopes, to the expected gamma-ray
flux from collisions of Galactic cosmic rays and dark matter in the center of
the Milky Way. We also derive sensitivity prospects for the upcoming Cherenkov
Telescope Array (CTA) and Southern Wide-field Gamma-ray Observatory (SWGO). The
expected sensitivity allows us to probe a poorly-constrained range of dark
matter masses so far, ranging from keV to sub-GeV, and provide complementary
constraints on the dark matter-proton scattering cross section traditionally
probed by deep underground direct dark matter experiments.
| [
{
"created": "Thu, 16 Nov 2023 09:01:29 GMT",
"version": "v1"
}
] | 2023-11-17 | [
[
"Reis",
"Igor",
""
],
[
"Moulin",
"Emmanuel",
""
],
[
"Viana",
"Aion",
""
]
] | A wealth of astrophysical and cosmological observational evidence shows that the matter content of the universe is made of about 85$\%$ of non-baryonic dark matter. Huge experimental efforts have been deployed to look for the direct detection of dark matter via their scattering on target nucleons, their production in colliders, and their indirect detection via their annihilation products. Inelastic scattering of high-energy cosmic rays off dark matter particles populating the Milky Way halo would produce secondary gamma rays in the final state from the decay of the neutral pions produced in such interactions, providing a new avenue to probe dark matter properties. We compute here the sensitivity for H.E.S.S.-like observatory, a current-generation ground-based Cherenkov telescopes, to the expected gamma-ray flux from collisions of Galactic cosmic rays and dark matter in the center of the Milky Way. We also derive sensitivity prospects for the upcoming Cherenkov Telescope Array (CTA) and Southern Wide-field Gamma-ray Observatory (SWGO). The expected sensitivity allows us to probe a poorly-constrained range of dark matter masses so far, ranging from keV to sub-GeV, and provide complementary constraints on the dark matter-proton scattering cross section traditionally probed by deep underground direct dark matter experiments. |
hep-ph/0101267 | Loyal Durand | Loyal Durand, Phuoc Ha, and Gregory Jaczko | Effective field theory and the quark model | 25 pages, revtex, no figures | Phys.Rev. D64 (2001) 014008 | 10.1103/PhysRevD.64.014008 | null | hep-ph | null | We analyze the connections between the quark model (QM) and the description
of hadrons in the low-momentum limit of heavy-baryon effective field theory in
QCD. By using a three-flavor-index representation for the effective baryon
fields, we show that the ``nonrelativistic'' constituent QM for baryon masses
and moments is completely equivalent through O(m_s) to a parametrization of the
relativistic field theory in a general spin--flavor basis. The flavor and spin
variables can be identified with those of effective valence quarks. Conversely,
the spin-flavor description clarifies the structure and dynamical
interpretation of the chiral expansion in effective field theory, and provides
a direct connection between the field theory and the semirelativistic models
for hadrons used in successful dynamical calculations. This allows dynamical
information to be incorporated directly into the chiral expansion. We find, for
example, that the striking success of the additive QM for baryon magnetic
moments is a consequence of the relative smallness of the non-additive
spin-dependent corrections.
| [
{
"created": "Tue, 23 Jan 2001 23:26:27 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Durand",
"Loyal",
""
],
[
"Ha",
"Phuoc",
""
],
[
"Jaczko",
"Gregory",
""
]
] | We analyze the connections between the quark model (QM) and the description of hadrons in the low-momentum limit of heavy-baryon effective field theory in QCD. By using a three-flavor-index representation for the effective baryon fields, we show that the ``nonrelativistic'' constituent QM for baryon masses and moments is completely equivalent through O(m_s) to a parametrization of the relativistic field theory in a general spin--flavor basis. The flavor and spin variables can be identified with those of effective valence quarks. Conversely, the spin-flavor description clarifies the structure and dynamical interpretation of the chiral expansion in effective field theory, and provides a direct connection between the field theory and the semirelativistic models for hadrons used in successful dynamical calculations. This allows dynamical information to be incorporated directly into the chiral expansion. We find, for example, that the striking success of the additive QM for baryon magnetic moments is a consequence of the relative smallness of the non-additive spin-dependent corrections. |
hep-ph/9602355 | Frank Cuypers | Frank Cuypers (PSI) | Leptoquarks in $e^-\gamma$ Collisions | 8 pages, talk presented at the LCWS95 Workshop on Physics and
Experiments with Linear Colliders held at Morioka, Sep 8-13, 1995 | null | null | MPI-PhT/95-129 | hep-ph | null | We discuss the leptoquark discovery potential of $e^-\gamma$ scattering and
show how polarization and angular distributions can be used to differentiate
the different types of leptoquarks.
| [
{
"created": "Wed, 21 Feb 1996 08:09:26 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Cuypers",
"Frank",
"",
"PSI"
]
] | We discuss the leptoquark discovery potential of $e^-\gamma$ scattering and show how polarization and angular distributions can be used to differentiate the different types of leptoquarks. |
2001.11941 | Agustin Sabio Vera | Agust\'in Sabio Vera | A few topics in BFKL phenomenology at hadron colliders | Contribution to the memorial volume "From the past to the future -
the legacy of Lev Lipatov" | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | This is a personal recollection of several results involving the
phenomenological study of the multi-Regge limit of scattering amplitudes. None
of them would have been possible without the encouragement and constant support
from Lev Nikolaevich Lipatov.
| [
{
"created": "Fri, 31 Jan 2020 16:36:32 GMT",
"version": "v1"
},
{
"created": "Thu, 4 Jun 2020 15:16:03 GMT",
"version": "v2"
}
] | 2020-06-05 | [
[
"Vera",
"Agustín Sabio",
""
]
] | This is a personal recollection of several results involving the phenomenological study of the multi-Regge limit of scattering amplitudes. None of them would have been possible without the encouragement and constant support from Lev Nikolaevich Lipatov. |
2207.07354 | Monika Blanke | Monika Blanke | Theory Perspective on Heavy Flavour Physics | 11 pages, 4 figures. Proceedings based on plenary talk at The Tenth
Annual Conference on Large Hadron Collider Physics - LHCP2022, May 16-20
2022. v2: references added | null | null | TTP22-046, P3H-22-073 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the Spring 2022 status of the current $B$ anomalies and their
possible interpretation in terms of New Phsyics. We also discuss the discovery
potential of targeted LHC and future collider searches for the underlying new
particles and their complementarity with low-energy flavour observables.
| [
{
"created": "Fri, 15 Jul 2022 09:08:37 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Jul 2022 08:13:38 GMT",
"version": "v2"
}
] | 2022-07-22 | [
[
"Blanke",
"Monika",
""
]
] | We review the Spring 2022 status of the current $B$ anomalies and their possible interpretation in terms of New Phsyics. We also discuss the discovery potential of targeted LHC and future collider searches for the underlying new particles and their complementarity with low-energy flavour observables. |
hep-ph/0307092 | Ahmed Ali | A. Ali (CERN) and A.Ya. Parkhomenko (Univ. Bern) | The $\eta^\prime g^* g^{(*)}$ Vertex Including the $\eta^\prime$-Meson
Mass | 26 pages, 6 figures; use epsfig.sty; submitted to the European
Physical Journal C | Eur.Phys.J.C30:367-380,2003 | 10.1140/epjc/s2003-01302-6 | CERN-TH/2003-063; BUTP-2003/04 | hep-ph | null | The $\eta^\prime g^* g^{(*)}$ effective vertex function is calculated in the
QCD hard-scattering approach, taking into account the $\eta^\prime$-meson mass.
We work in the approximation in which only one non-leading Gegenbauer moment
for both the quark-antiquark and the gluonic light-cone distribution amplitudes
for the $\eta^\prime$-meson is kept. The vertex function with one off-shell
gluon is shown to have the form (valid for $| q_1^2 | > m_{\eta^\prime}^2$)
$F_{\eta^\prime g^* g} (q_1^2, 0, m_{\eta^\prime}^2) = m_{\eta^\prime}^2
H(q_1^2)/(q_1^2 - m_{\eta^\prime}^2)$, where $H(q_1^2)$ is a slowly varying
function, derived analytically in this paper. The resulting vertex function is
in agreement with the phenomenologically inferred form of this vertex obtained
from an analysis of the CLEO data on the $\eta^\prime$-meson energy spectrum in
the decay $\Upsilon(1S) \to \eta^\prime X$. We also present an interpolating
formula for the vertex function $F_{\eta^\prime g^* g} (q_1^2, 0,
m_{\eta^\prime}^2)$ for the space-like region of the virtuality $q_1^2$, which
satisfies the QCD anomaly normalization for on-shell gluons and the
perturbative-QCD result for the gluon virtuality $| q_1^2| \gtrsim 2$ GeV$^2$.
| [
{
"created": "Mon, 7 Jul 2003 16:19:38 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Ali",
"A.",
"",
"CERN"
],
[
"Parkhomenko",
"A. Ya.",
"",
"Univ. Bern"
]
] | The $\eta^\prime g^* g^{(*)}$ effective vertex function is calculated in the QCD hard-scattering approach, taking into account the $\eta^\prime$-meson mass. We work in the approximation in which only one non-leading Gegenbauer moment for both the quark-antiquark and the gluonic light-cone distribution amplitudes for the $\eta^\prime$-meson is kept. The vertex function with one off-shell gluon is shown to have the form (valid for $| q_1^2 | > m_{\eta^\prime}^2$) $F_{\eta^\prime g^* g} (q_1^2, 0, m_{\eta^\prime}^2) = m_{\eta^\prime}^2 H(q_1^2)/(q_1^2 - m_{\eta^\prime}^2)$, where $H(q_1^2)$ is a slowly varying function, derived analytically in this paper. The resulting vertex function is in agreement with the phenomenologically inferred form of this vertex obtained from an analysis of the CLEO data on the $\eta^\prime$-meson energy spectrum in the decay $\Upsilon(1S) \to \eta^\prime X$. We also present an interpolating formula for the vertex function $F_{\eta^\prime g^* g} (q_1^2, 0, m_{\eta^\prime}^2)$ for the space-like region of the virtuality $q_1^2$, which satisfies the QCD anomaly normalization for on-shell gluons and the perturbative-QCD result for the gluon virtuality $| q_1^2| \gtrsim 2$ GeV$^2$. |
2309.07860 | Sarunas Verner | Roy T. Forestano, Konstantin T. Matchev, Katia Matcheva, Alexander
Roman, Eyup B. Unlu, Sarunas Verner | Identifying the Group-Theoretic Structure of Machine-Learned Symmetries | 10 pages, 8 figures, 2 tables | null | null | null | hep-ph cs.LG hep-th math-ph math.GR math.MP | http://creativecommons.org/licenses/by/4.0/ | Deep learning was recently successfully used in deriving symmetry
transformations that preserve important physics quantities. Being completely
agnostic, these techniques postpone the identification of the discovered
symmetries to a later stage. In this letter we propose methods for examining
and identifying the group-theoretic structure of such machine-learned
symmetries. We design loss functions which probe the subalgebra structure
either during the deep learning stage of symmetry discovery or in a subsequent
post-processing stage. We illustrate the new methods with examples from the
U(n) Lie group family, obtaining the respective subalgebra decompositions. As
an application to particle physics, we demonstrate the identification of the
residual symmetries after the spontaneous breaking of non-Abelian gauge
symmetries like SU(3) and SU(5) which are commonly used in model building.
| [
{
"created": "Thu, 14 Sep 2023 17:03:50 GMT",
"version": "v1"
}
] | 2023-09-15 | [
[
"Forestano",
"Roy T.",
""
],
[
"Matchev",
"Konstantin T.",
""
],
[
"Matcheva",
"Katia",
""
],
[
"Roman",
"Alexander",
""
],
[
"Unlu",
"Eyup B.",
""
],
[
"Verner",
"Sarunas",
""
]
] | Deep learning was recently successfully used in deriving symmetry transformations that preserve important physics quantities. Being completely agnostic, these techniques postpone the identification of the discovered symmetries to a later stage. In this letter we propose methods for examining and identifying the group-theoretic structure of such machine-learned symmetries. We design loss functions which probe the subalgebra structure either during the deep learning stage of symmetry discovery or in a subsequent post-processing stage. We illustrate the new methods with examples from the U(n) Lie group family, obtaining the respective subalgebra decompositions. As an application to particle physics, we demonstrate the identification of the residual symmetries after the spontaneous breaking of non-Abelian gauge symmetries like SU(3) and SU(5) which are commonly used in model building. |
2211.03873 | Joseph Muse | Tom Eichlersmith, Jeremiah Mans, Omar Moreno, Joseph Muse, Michael
Revering and Natalia Toro | Simulation of Dark Bremsstrahlung in GEANT4 | 14 pages, 10 figures | null | 10.1016/j.cpc.2023.108690 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | A technique for the simulation of dark bremsstrahlung for electrons and muons
in GEANT4 is presented. The total cross section is calculated using the
Weizs\"{a}cker-Williams approximation and the outgoing kinematics are produced
by scaling events produced in MadGraph/MadEvent to lower incident lepton
energies, allowing the simulation to account for thick targets and lepton
sources without fixed energies. Compared with dedicated samples produced at an
arbitrary particle energy, typical precision of better than 5% is achieved.
| [
{
"created": "Mon, 7 Nov 2022 21:24:15 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Feb 2023 01:35:08 GMT",
"version": "v2"
}
] | 2023-03-01 | [
[
"Eichlersmith",
"Tom",
""
],
[
"Mans",
"Jeremiah",
""
],
[
"Moreno",
"Omar",
""
],
[
"Muse",
"Joseph",
""
],
[
"Revering",
"Michael",
""
],
[
"Toro",
"Natalia",
""
]
] | A technique for the simulation of dark bremsstrahlung for electrons and muons in GEANT4 is presented. The total cross section is calculated using the Weizs\"{a}cker-Williams approximation and the outgoing kinematics are produced by scaling events produced in MadGraph/MadEvent to lower incident lepton energies, allowing the simulation to account for thick targets and lepton sources without fixed energies. Compared with dedicated samples produced at an arbitrary particle energy, typical precision of better than 5% is achieved. |
2311.17562 | Oleg Selyugin | O.V. Selyugin | Dependence of the structure of the elastic scattering amplitude on
Mandelstam variables at high energies | 9 pages, 4 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Analysis of new experimental data obtained by the TOTEM and ATLAS
Collaborations at the LHC together with old data obtained at the SPS and
Tevatron colliders at small momentum transferin the framework of the high
energy generalized structure (HEGS) model allows one to determine the
dependence of different parts of the hadron elastic scattering amplitude on the
mandelstam kinematic variables the $s$ and $t$
| [
{
"created": "Wed, 29 Nov 2023 11:51:11 GMT",
"version": "v1"
}
] | 2023-11-30 | [
[
"Selyugin",
"O. V.",
""
]
] | Analysis of new experimental data obtained by the TOTEM and ATLAS Collaborations at the LHC together with old data obtained at the SPS and Tevatron colliders at small momentum transferin the framework of the high energy generalized structure (HEGS) model allows one to determine the dependence of different parts of the hadron elastic scattering amplitude on the mandelstam kinematic variables the $s$ and $t$ |
hep-ph/0307149 | Walter Grimus | W. Grimus | Neutrino Physics - Theory | 46 pages, LaTeX, 8 figures; Lectures given at the 41. Internationale
Universit\"atswochen f\"ur Theoretische Physik, Flavour Physics, Schladming,
Styria, Austria, February 22--28, 2003. Some references and clarifications
added, misprints corrected | null | 10.1007/b98411 | UWThPh-2003-16 | hep-ph | null | We discuss recent developments in neutrino physics and focus, in particular,
on neutrino oscillations and matter effects of three light active neutrinos.
Moreover, we discuss the difference between Dirac and Majorana neutrinos,
neutrinoless $\beta\beta$-decay, absolute neutrino masses and electromagnetic
moments. Basic mechanisms and a few models for neutrino masses and mixing are
also presented.
| [
{
"created": "Thu, 10 Jul 2003 17:49:48 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Jul 2003 15:07:29 GMT",
"version": "v2"
}
] | 2017-08-23 | [
[
"Grimus",
"W.",
""
]
] | We discuss recent developments in neutrino physics and focus, in particular, on neutrino oscillations and matter effects of three light active neutrinos. Moreover, we discuss the difference between Dirac and Majorana neutrinos, neutrinoless $\beta\beta$-decay, absolute neutrino masses and electromagnetic moments. Basic mechanisms and a few models for neutrino masses and mixing are also presented. |
1710.04402 | Sarah Aghababaei | S. Aghababaei and M. Haghighat | Lorentz violation parameters and noncommutative scale | 32 pages, to appear in PRD | Phys. Rev. D 96, 075017 (2017) | 10.1103/PhysRevD.96.075017 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider the noncommutative Standard Model that contains Lorentz symmetry
violation as a subset of the Standard Model extension. We introduce a constant
electromagnetic field as a background to derive mutual relations between the
free parameters of both theories. As the Lorentz violation parameters of the
Standard Model extension are extensively explored in different experiments and
many stringent bounds on these parameters are available, we can find new bounds
on the scale of noncommutativity of the order of a few to tens of teraelectron
volts.
| [
{
"created": "Thu, 12 Oct 2017 08:11:31 GMT",
"version": "v1"
}
] | 2017-10-17 | [
[
"Aghababaei",
"S.",
""
],
[
"Haghighat",
"M.",
""
]
] | We consider the noncommutative Standard Model that contains Lorentz symmetry violation as a subset of the Standard Model extension. We introduce a constant electromagnetic field as a background to derive mutual relations between the free parameters of both theories. As the Lorentz violation parameters of the Standard Model extension are extensively explored in different experiments and many stringent bounds on these parameters are available, we can find new bounds on the scale of noncommutativity of the order of a few to tens of teraelectron volts. |
hep-ph/0208157 | Paul Frampton | P.H. Frampton, S.L. Glashow and T. Yanagida | Cosmological Sign of Neutrino CP Violation | 3 pages LaTeX | Phys.Lett. B548 (2002) 119-121 | 10.1016/S0370-2693(02)02853-8 | CERN-TH/2002-193 | hep-ph hep-th | null | It is shown how, in a class of models, the sign of the baryon number of the
universe can be related to CP violation in neutrino oscillation experiments.
| [
{
"created": "Fri, 16 Aug 2002 00:04:40 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Aug 2002 23:58:15 GMT",
"version": "v2"
},
{
"created": "Tue, 8 Oct 2002 18:33:31 GMT",
"version": "v3"
}
] | 2009-11-07 | [
[
"Frampton",
"P. H.",
""
],
[
"Glashow",
"S. L.",
""
],
[
"Yanagida",
"T.",
""
]
] | It is shown how, in a class of models, the sign of the baryon number of the universe can be related to CP violation in neutrino oscillation experiments. |
1005.2667 | Tomasz Partyka | Tomasz L. Partyka | Non-uniform chiral and 2SC color superconducting phases, taking into
account the non-zero current quark mass | null | Mod.Phys.Lett.A26:543-556,2011 | 10.1142/S0217732311035055 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have shown, that the possibility of the existence of the mixed phase of
the non-uniform chiral (NCh) and the color superconducting (2SC) ground state
depends significantly on the choice of the parameters and type of the
regularization scheme. Our calculations indicates, that in the 3d cut-off
regularization scheme, the mixed region of the NCh and the 2SC phases exists
for a broad set of NJL model parameters. However, in the Schwinger
regularization scheme, if parameters are fitted to the physical quantities in
the vacuum, then, the mixed region of the NCh and the 2SC phases does not
exists.
| [
{
"created": "Sat, 15 May 2010 11:04:10 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Sep 2010 10:43:39 GMT",
"version": "v2"
}
] | 2015-03-17 | [
[
"Partyka",
"Tomasz L.",
""
]
] | We have shown, that the possibility of the existence of the mixed phase of the non-uniform chiral (NCh) and the color superconducting (2SC) ground state depends significantly on the choice of the parameters and type of the regularization scheme. Our calculations indicates, that in the 3d cut-off regularization scheme, the mixed region of the NCh and the 2SC phases exists for a broad set of NJL model parameters. However, in the Schwinger regularization scheme, if parameters are fitted to the physical quantities in the vacuum, then, the mixed region of the NCh and the 2SC phases does not exists. |
2204.04237 | Victor Branco Valera Baca | Victor Branco Valera, Mauricio Bustamante, Christian Glaser | The ultra-high-energy neutrino-nucleon cross section: measurement
forecasts for an era of cosmic EeV-neutrino discovery | 32 pages, 21 figures, 2 tables, plus appendix and references. Fixed
Fig. 15, by multiplying muon background x10 (1 years -> 10 years).
Conclusions unchanged, only the figure is changed, calculations are unchanged | null | 10.1007/JHEP06(2022)105 | null | hep-ph astro-ph.HE hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Neutrino interactions with protons and neutrons probe their deep structure
and may reveal new physics. The higher the neutrino energy, the sharper the
probe. So far, the neutrino-nucleon ($\nu N$) cross section is known across
neutrino energies from a few hundred MeV to a few PeV. Soon, ultra-high-energy
(UHE) cosmic neutrinos, with energies above 100 PeV, could take us farther. So
far, they have evaded discovery, but upcoming UHE neutrino telescopes endeavor
to find them. We present the first detailed measurement forecasts of the UHE
$\nu N$ cross section, geared to IceCube-Gen2, one of the leading detectors
under planning. We use state-of-the-art ingredients in every stage of our
forecasts: in the UHE neutrino flux predictions, the neutrino propagation
inside Earth, the emission of neutrino-induced radio signals in the detector,
their propagation and detection, and the treatment of backgrounds. After 10
years, if at least a few tens of UHE neutrino-induced events are detected,
IceCube-Gen2 could measure the $\nu N$ cross section at center-of-mass energies
of $\sqrt{s} \approx 10-100$ TeV for the first time, with a precision
comparable to that of its theory prediction.
| [
{
"created": "Fri, 8 Apr 2022 18:12:49 GMT",
"version": "v1"
},
{
"created": "Thu, 1 Sep 2022 10:33:52 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Dec 2022 16:12:48 GMT",
"version": "v3"
}
] | 2022-12-09 | [
[
"Valera",
"Victor Branco",
""
],
[
"Bustamante",
"Mauricio",
""
],
[
"Glaser",
"Christian",
""
]
] | Neutrino interactions with protons and neutrons probe their deep structure and may reveal new physics. The higher the neutrino energy, the sharper the probe. So far, the neutrino-nucleon ($\nu N$) cross section is known across neutrino energies from a few hundred MeV to a few PeV. Soon, ultra-high-energy (UHE) cosmic neutrinos, with energies above 100 PeV, could take us farther. So far, they have evaded discovery, but upcoming UHE neutrino telescopes endeavor to find them. We present the first detailed measurement forecasts of the UHE $\nu N$ cross section, geared to IceCube-Gen2, one of the leading detectors under planning. We use state-of-the-art ingredients in every stage of our forecasts: in the UHE neutrino flux predictions, the neutrino propagation inside Earth, the emission of neutrino-induced radio signals in the detector, their propagation and detection, and the treatment of backgrounds. After 10 years, if at least a few tens of UHE neutrino-induced events are detected, IceCube-Gen2 could measure the $\nu N$ cross section at center-of-mass energies of $\sqrt{s} \approx 10-100$ TeV for the first time, with a precision comparable to that of its theory prediction. |
2003.11751 | Anirban Karan | Priyotosh Bandyopadhyay, Saunak Dutta, Anirban Karan | Investigating the Production of Leptoquarks by Means of Zeros of
Amplitude at Photon Electron Collider | 46 pages, 14 figures, 15 tables, accepted in EPJC. The effects of
non-monochromatic photons have been included | Eur. Phys. J. C 80 (2020) 6, 573 | 10.1140/epjc/s10052-020-8083-7 | IITH-PH-0003/20 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Leptoquarks are one of the possible candidates for explaining various
anomalies in flavour physics. Nonetheless, their existence is yet to be
confirmed from experimental side. In this paper we have shown how zeros of
single photon tree-level amplitude can be used to extract information about
leptoquarks in case of $e$-$\gamma$ colliders. Small number of standard model
backgrounds keep the signal clean in this kind of colliders. Unlike other
colliders, the zeros of single photon amplitude here depend on $\sqrt{s}$ as
well as the mass of leptoquark along with its electric charge. We perform a
PYTHIA based simulation for reconstructing the leptoquark from its decay
products of first generation and estimating the background with luminosity of
100 fb$^{-1}$. Our analysis is done for all the leptoquarks that can be seen at
$e$-$\gamma$ collider with three different masses (70 GeV, 650 GeV and 1 TeV)
and three different centre of momentum energy (200 GeV, 2 TeV and 3 TeV). The
effects of non-monochromatic photons on the zeros of amplitude under laser
backscattering and equivalent photon approximation have also been addressed.
| [
{
"created": "Thu, 26 Mar 2020 05:50:47 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Jun 2020 10:58:09 GMT",
"version": "v2"
}
] | 2020-07-15 | [
[
"Bandyopadhyay",
"Priyotosh",
""
],
[
"Dutta",
"Saunak",
""
],
[
"Karan",
"Anirban",
""
]
] | Leptoquarks are one of the possible candidates for explaining various anomalies in flavour physics. Nonetheless, their existence is yet to be confirmed from experimental side. In this paper we have shown how zeros of single photon tree-level amplitude can be used to extract information about leptoquarks in case of $e$-$\gamma$ colliders. Small number of standard model backgrounds keep the signal clean in this kind of colliders. Unlike other colliders, the zeros of single photon amplitude here depend on $\sqrt{s}$ as well as the mass of leptoquark along with its electric charge. We perform a PYTHIA based simulation for reconstructing the leptoquark from its decay products of first generation and estimating the background with luminosity of 100 fb$^{-1}$. Our analysis is done for all the leptoquarks that can be seen at $e$-$\gamma$ collider with three different masses (70 GeV, 650 GeV and 1 TeV) and three different centre of momentum energy (200 GeV, 2 TeV and 3 TeV). The effects of non-monochromatic photons on the zeros of amplitude under laser backscattering and equivalent photon approximation have also been addressed. |
hep-ph/9907391 | Adam K. Leibovich | Adam K. Leibovich, and I. Z. Rothstein (Carnegie Mellon University) | The Resummed Rate for B -> X_s gamma | 17 pages, 5 figures | Phys.Rev. D61 (2000) 074006 | 10.1103/PhysRevD.61.074006 | null | hep-ph | null | In this paper we investigate the effect of the resummation of threshold logs
on the rate for B -> X_s gamma. We calculate the differential rate
dGamma/dE_gamma including the infinite set of terms of the form alpha_s^n
log^{n+1}(1-x) and alpha_s^n log^n(1-x) in the Sudakov exponent. The
resummation is potentially important since these logs turn into
log(2E_{cut}/m_b), when the rate is integrated from the lower cut
x=2E_{cut}/m_b to 1. The resummed rate is then convolved with models for the
structure function to study whether or not the logs will be enhanced due to the
fermi motion of the heavy quark. A detailed discussion of the accuracy of the
calculation with and without the inclusion of the non-perturbative effects
dictated by the B meson structure function is given. We also investigate the
first moment with respect to (1-x), which can be used to measure \bar\Lambda
and lambda_1. It is shown that there are some two loop corrections which are
just as large as the alpha_s^2 beta_0 term, which are usually expected to
dominate. We conclude that, for the present energy cut, the threshold logs do
not form a dominant sub-series and therefore their resummation is unnecessary.
Thus, the prospects for predicting the rate for B -> X_s gamma accurately,
given the present energy cut, are promising.
| [
{
"created": "Fri, 16 Jul 1999 15:38:20 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Leibovich",
"Adam K.",
"",
"Carnegie Mellon University"
],
[
"Rothstein",
"I. Z.",
"",
"Carnegie Mellon University"
]
] | In this paper we investigate the effect of the resummation of threshold logs on the rate for B -> X_s gamma. We calculate the differential rate dGamma/dE_gamma including the infinite set of terms of the form alpha_s^n log^{n+1}(1-x) and alpha_s^n log^n(1-x) in the Sudakov exponent. The resummation is potentially important since these logs turn into log(2E_{cut}/m_b), when the rate is integrated from the lower cut x=2E_{cut}/m_b to 1. The resummed rate is then convolved with models for the structure function to study whether or not the logs will be enhanced due to the fermi motion of the heavy quark. A detailed discussion of the accuracy of the calculation with and without the inclusion of the non-perturbative effects dictated by the B meson structure function is given. We also investigate the first moment with respect to (1-x), which can be used to measure \bar\Lambda and lambda_1. It is shown that there are some two loop corrections which are just as large as the alpha_s^2 beta_0 term, which are usually expected to dominate. We conclude that, for the present energy cut, the threshold logs do not form a dominant sub-series and therefore their resummation is unnecessary. Thus, the prospects for predicting the rate for B -> X_s gamma accurately, given the present energy cut, are promising. |
hep-ph/0610188 | George Rupp | George Rupp and Eef van Beveren | Multichannel calculation of the very narrow $D_{s0}^*(2317)$ and the
very broad $D_0^*(2300-2400)$ | 3 pages, EPJ LaTeX, 2 Postscript figures, 1 table; parallel talk at
the IVth International Conference on Quarks and Nuclear Physics (QNP06),
Madrid, 5-10 June 2006 | Eur.Phys.J.A31:698-700,2007 | 10.1140/epja/i2006-10269-3 | null | hep-ph | null | The narrow $D_{s0}^{\ast}$(2317) and broad $D_0^{\ast}$(2300-2400) charmed
scalar mesons and their radial excitations are described in a coupled-channel
quark model that also reproduces the properties of the light scalar nonet. All
two-meson channels containing ground-state pseudoscalars and vectors are
included. The parameters are chosen fixed at published values, except for the
overall coupling constant $\lambda$, which is fine-tuned to reproduce the
$D_{s0}^{\ast}$(2317) mass, and a damping constant $\alpha$ for subthreshold
contributions. Variations of $\lambda$ and $D_0^{\ast}$(2300-2400) pole
postions are studied for different $\alpha$ values. Calculated cross sections
for $S$-wave $DK$ and $D\pi$ scattering, as well as resonance pole positions,
are given for the value of $\alpha$ that fits the light scalars. The thus
predicted radially excited state ${D_{s0}^*}'$(2850), with a width of about 50
MeV, seems to have been observed already.
| [
{
"created": "Mon, 16 Oct 2006 08:16:54 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Rupp",
"George",
""
],
[
"van Beveren",
"Eef",
""
]
] | The narrow $D_{s0}^{\ast}$(2317) and broad $D_0^{\ast}$(2300-2400) charmed scalar mesons and their radial excitations are described in a coupled-channel quark model that also reproduces the properties of the light scalar nonet. All two-meson channels containing ground-state pseudoscalars and vectors are included. The parameters are chosen fixed at published values, except for the overall coupling constant $\lambda$, which is fine-tuned to reproduce the $D_{s0}^{\ast}$(2317) mass, and a damping constant $\alpha$ for subthreshold contributions. Variations of $\lambda$ and $D_0^{\ast}$(2300-2400) pole postions are studied for different $\alpha$ values. Calculated cross sections for $S$-wave $DK$ and $D\pi$ scattering, as well as resonance pole positions, are given for the value of $\alpha$ that fits the light scalars. The thus predicted radially excited state ${D_{s0}^*}'$(2850), with a width of about 50 MeV, seems to have been observed already. |
1706.03116 | Mario Reig | Mario Reig, Jos\'e W.F. Valle, C.A. Vaquera-Araujo, Frank Wilczek | A Model of Comprehensive Unification | 5 pages, 2 figures. Published version | Phys.Lett. B774 (2017) 667-670 | 10.1016/j.physletb.2017.10.038 | IFIC/17-28, MIT-CTP/4913 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Comprehensive - that is, gauge and family - unification using spinors has
many attractive features, but it has been challenged to explain chirality.
Here, by combining an orbifold construction with more traditional ideas, we
address that difficulty. Our candidate model features three chiral families and
leads to an acceptable result for quantitative unification of couplings. A
potential target for accelerator and astronomical searches emerges.
| [
{
"created": "Fri, 9 Jun 2017 20:35:13 GMT",
"version": "v1"
},
{
"created": "Mon, 30 Oct 2017 15:24:47 GMT",
"version": "v2"
}
] | 2017-10-31 | [
[
"Reig",
"Mario",
""
],
[
"Valle",
"José W. F.",
""
],
[
"Vaquera-Araujo",
"C. A.",
""
],
[
"Wilczek",
"Frank",
""
]
] | Comprehensive - that is, gauge and family - unification using spinors has many attractive features, but it has been challenged to explain chirality. Here, by combining an orbifold construction with more traditional ideas, we address that difficulty. Our candidate model features three chiral families and leads to an acceptable result for quantitative unification of couplings. A potential target for accelerator and astronomical searches emerges. |
hep-ph/9506439 | Zepeda | William A. Ponce, Arnulfo Zepeda and Jes\'us M. Mira | Is U(1)$_H$ a Good Family Symmetry? | 10 pages, Accepted for publication in Z. Phys. C | Z.Phys. C69 (1996) 683-686 | null | null | hep-ph | null | We analyze U(1)$_H$ as a horizontal symmetry and its possibilities to explain
the known elementary-fermion masses. We find that only two candidates, in the
context of SU(3)$_c\otimes$SU(2)$_L\otimes$U(1)$_Y\otimes$U(1)$_H$
nonsupersymmetric, are able to fit the experimental result m$_b<<$m$_t$.
| [
{
"created": "Tue, 27 Jun 1995 16:38:56 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Ponce",
"William A.",
""
],
[
"Zepeda",
"Arnulfo",
""
],
[
"Mira",
"Jesús M.",
""
]
] | We analyze U(1)$_H$ as a horizontal symmetry and its possibilities to explain the known elementary-fermion masses. We find that only two candidates, in the context of SU(3)$_c\otimes$SU(2)$_L\otimes$U(1)$_Y\otimes$U(1)$_H$ nonsupersymmetric, are able to fit the experimental result m$_b<<$m$_t$. |
hep-ph/0405295 | Valeriu Zetocha | Valeriu Zetocha | Applications of instantons to hadronic processes | Ph.D. thesis. Advisor: Thomas Schaefer | null | null | null | hep-ph | null | In this thesis we study two processes in which instantons may play an
important role: the decays of charmonium states $\eta_c$, $\chi_c$ and glueball
and the OZI violation in channels relevant to the proton spin decomposition
puzzle. We also present an algorithm for computation of integrals over compact
groups and exemplify it on integrals over SU(N) fundamental and adjoint
representations.
| [
{
"created": "Sun, 30 May 2004 01:00:23 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Zetocha",
"Valeriu",
""
]
] | In this thesis we study two processes in which instantons may play an important role: the decays of charmonium states $\eta_c$, $\chi_c$ and glueball and the OZI violation in channels relevant to the proton spin decomposition puzzle. We also present an algorithm for computation of integrals over compact groups and exemplify it on integrals over SU(N) fundamental and adjoint representations. |
hep-ph/0007053 | Fukuko Yuasa | F.Yuasa, J.Fujimoto, T.Ishikawa (KEK), M.Jimbo (Tokyo Management
College), T.Kaneko (Meiji-Gakuin University), K.Kato (Kogakuin University),
S.Kawabata (KEK), T.Kon (Seikei University), Y.Kurihara (KEK), M.Kuroda
(Meiji-Gakuin University), N.Nakazawa (Kogakuin University), Y.Shimizu (KEK),
H.Tanaka (Rikkyo University) | Automatic Computation of Cross Sections in HEP | 6 pages, Latex, ICCP5 | Prog.Theor.Phys.Suppl. 138 (2000) 18-23 | 10.1143/PTPS.138.18 | Progress of Theoretical Physics Supplement No. 138, 2000,
KEK-Preprint 99-155, KEK-CP-099 | hep-ph | null | For the study of reactions in High Energy Physics (HEP) automatic computation
systems have been developed and are widely used nowadays. GRACE is one of such
systems and it has achieved much success in analyzing experimental data. Since
we deal with the cross section whose value can be given by calculating hundreds
of Feynman diagrams, we manage the large scale calculation, so that effective
symbolic manipulation, the treat of singularity in the numerical integration
are required. The talk will describe the software design of GRACE system and
computational techniques in the GRACE.
| [
{
"created": "Thu, 6 Jul 2000 04:12:34 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Yuasa",
"F.",
"",
"KEK"
],
[
"Fujimoto",
"J.",
"",
"KEK"
],
[
"Ishikawa",
"T.",
"",
"KEK"
],
[
"Jimbo",
"M.",
"",
"Tokyo Management\n College"
],
[
"Kaneko",
"T.",
"",
"Meiji-Gakuin University"
],
[
"Kato",
... | For the study of reactions in High Energy Physics (HEP) automatic computation systems have been developed and are widely used nowadays. GRACE is one of such systems and it has achieved much success in analyzing experimental data. Since we deal with the cross section whose value can be given by calculating hundreds of Feynman diagrams, we manage the large scale calculation, so that effective symbolic manipulation, the treat of singularity in the numerical integration are required. The talk will describe the software design of GRACE system and computational techniques in the GRACE. |
0810.1987 | Jan Martin Pawlowski | Christian S. Fischer, Axel Maas, Jan M. Pawlowski | On the infrared behavior of Landau gauge Yang-Mills theory | 23 pages, 11 figures, v2:clarifications added and typos corrected;
version accepted by Annals of Physics | Annals Phys.324:2408-2437,2009 | 10.1016/j.aop.2009.07.009 | null | hep-ph hep-lat hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the properties of ghost and gluon propagators in the deep infrared
momentum region of Landau gauge Yang-Mills theory. Within the framework of
Dyson-Schwinger equations and the functional renormalization group we
demonstrate that it is only a matter of infrared boundary conditions whether
infrared scaling or decoupling occurs. We argue that the second possibility is
at odds with global BRST symmetry in the confining phase. For this purpose we
improve upon existing truncation schemes in particular with respect to
transversality and renormalization.
| [
{
"created": "Mon, 13 Oct 2008 16:49:46 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Jul 2009 07:55:39 GMT",
"version": "v2"
}
] | 2010-04-30 | [
[
"Fischer",
"Christian S.",
""
],
[
"Maas",
"Axel",
""
],
[
"Pawlowski",
"Jan M.",
""
]
] | We discuss the properties of ghost and gluon propagators in the deep infrared momentum region of Landau gauge Yang-Mills theory. Within the framework of Dyson-Schwinger equations and the functional renormalization group we demonstrate that it is only a matter of infrared boundary conditions whether infrared scaling or decoupling occurs. We argue that the second possibility is at odds with global BRST symmetry in the confining phase. For this purpose we improve upon existing truncation schemes in particular with respect to transversality and renormalization. |
hep-ph/9507237 | Dr F. Caravaglios | F. Caravaglios and M. Moretti | An Algorithm to Compute Born Scattering Amplitudes without Feynman
Graphs | 12 pages , latex, 2 postscript figures appended | Phys.Lett.B358:332-338,1995 | 10.1016/0370-2693(95)00971-M | OUTP 9528P and SHEP 95-22 | hep-ph | null | In this paper we suggest an {\it iterative} algorithm to compute
automatically the scattering matrix elements of any given effective lagrangian,
$\Gamma$. By exploiting the relation between $\Gamma$ and the connected Green
function generator, $Z$, we provide a formula which does not require the use of
the Feynman graphs and it is suitable to implement a numerical routine. By
means of this algorithm we have built a relatively simple and fast fortran code
which we have used to calculate, at the tree level, the rate of four fermion
production at LEP I\negthinspace{I} (finding a very good agreement with
previous calculation) with and without the emission of one observable photon.
| [
{
"created": "Wed, 5 Jul 1995 20:43:07 GMT",
"version": "v1"
}
] | 2016-09-01 | [
[
"Caravaglios",
"F.",
""
],
[
"Moretti",
"M.",
""
]
] | In this paper we suggest an {\it iterative} algorithm to compute automatically the scattering matrix elements of any given effective lagrangian, $\Gamma$. By exploiting the relation between $\Gamma$ and the connected Green function generator, $Z$, we provide a formula which does not require the use of the Feynman graphs and it is suitable to implement a numerical routine. By means of this algorithm we have built a relatively simple and fast fortran code which we have used to calculate, at the tree level, the rate of four fermion production at LEP I\negthinspace{I} (finding a very good agreement with previous calculation) with and without the emission of one observable photon. |
0808.0358 | Dariusz Prorok | Dariusz Prorok, Ludwik Turko, David Blaschke | J/$\psi$ absorption in a multicomponent hadron gas | Presented at Joint Meeting Heidelberg-Liege-Paris-Wroclaw: Three Days
of Strong Interactions and Astrophysics (HLPW08), Spa, Liege, Belgium, 6-8
Mar 2008 | AIP Conf.Proc.1038:73-82,2008 | 10.1063/1.2987189 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A model for anomalous $J/\Psi$ suppression in high energy heavy ion
collisions is presented. As the additional suppression mechanism beyond
standard nuclear absorption inelastic $J/\Psi$ scattering with hadronic matter
is considered. Hadronic matter is modeled as an evolving multi-component gas of
point-like non-interacting particles (MCHG). Estimates for the sound velocity
of the MCHG are given and the equation of state is compared with Lattice QCD
data in the vicinity of the deconfinement phase transition. The approximate
cooling pattern caused by longitudinal expansion is presented. It is shown that
under these conditions the resulting $J/\Psi$ suppression pattern agrees well
with NA38 and NA50 data.
| [
{
"created": "Mon, 4 Aug 2008 15:00:16 GMT",
"version": "v1"
}
] | 2009-02-18 | [
[
"Prorok",
"Dariusz",
""
],
[
"Turko",
"Ludwik",
""
],
[
"Blaschke",
"David",
""
]
] | A model for anomalous $J/\Psi$ suppression in high energy heavy ion collisions is presented. As the additional suppression mechanism beyond standard nuclear absorption inelastic $J/\Psi$ scattering with hadronic matter is considered. Hadronic matter is modeled as an evolving multi-component gas of point-like non-interacting particles (MCHG). Estimates for the sound velocity of the MCHG are given and the equation of state is compared with Lattice QCD data in the vicinity of the deconfinement phase transition. The approximate cooling pattern caused by longitudinal expansion is presented. It is shown that under these conditions the resulting $J/\Psi$ suppression pattern agrees well with NA38 and NA50 data. |
1306.4273 | Paulo Beggio Cesar | Paulo Cesar Beggio | Oscillations of factorial cumulants to factorial moments ratio from an
eikonal approach | null | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the factorial moments (Fq), the factorial cumulants (Kq) and the
ratio of Kq to Fq (Hq = Kq=Fq) in pp/pp collisions using an updated approach,
in which the multiplicity distribution is related to the eikonal function. The
QCD inspired eikonal model adopted contains contributions of quark-quark,
quark-gluon and gluon-gluon interactions. Our work shows that the approach can
reproduce the collision energy dependence of the Fq moments, correctly predicts
that the first minimum of the Hq lies around q = 5 and qualitatively reproduces
the oscillations of the Hq moments, as shown in the experimental data and
predicted by QCD at preasymptotic energy. The result of this study seems to
indicate that the Hq oscillations are manifestation of semihard component in
the multiparticle production process. Predictions for multiplicity distribution
and Hq moments at the LHC energy of 14 TeV are presented.
| [
{
"created": "Tue, 18 Jun 2013 17:30:58 GMT",
"version": "v1"
}
] | 2013-06-19 | [
[
"Beggio",
"Paulo Cesar",
""
]
] | We study the factorial moments (Fq), the factorial cumulants (Kq) and the ratio of Kq to Fq (Hq = Kq=Fq) in pp/pp collisions using an updated approach, in which the multiplicity distribution is related to the eikonal function. The QCD inspired eikonal model adopted contains contributions of quark-quark, quark-gluon and gluon-gluon interactions. Our work shows that the approach can reproduce the collision energy dependence of the Fq moments, correctly predicts that the first minimum of the Hq lies around q = 5 and qualitatively reproduces the oscillations of the Hq moments, as shown in the experimental data and predicted by QCD at preasymptotic energy. The result of this study seems to indicate that the Hq oscillations are manifestation of semihard component in the multiparticle production process. Predictions for multiplicity distribution and Hq moments at the LHC energy of 14 TeV are presented. |
0805.3536 | Pavel Fileviez Perez | Pavel Fileviez Perez, Tao Han, Gui-Yu Huang, Tong Li, Kai Wang | Neutrino Masses and the LHC: Testing Type II Seesaw | 50 pages, 51 figures, minor corrections, one reference added, to
appear in Physical Review D | Phys.Rev.D78:015018,2008 | 10.1103/PhysRevD.78.015018 | MADPH-08-1510, NSF-KITP-08-65 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We demonstrate how to systematically test a well-motivated mechanism for
neutrino mass generation (Type-II seesaw) at the LHC, in which a Higgs triplet
is introduced. In the optimistic scenarios with a small Higgs triplet vacuum
expectation value vd < 10^{-4} GeV, one can look for clean signals of lepton
number violation in the decays of doubly charged and singly charged Higgs
bosons to distinguish the Normal Hierarchy (NH), the Inverted Hierarchy (IH)
and the Quasi-Degenerate (QD) spectrum for the light neutrino masses. The
observation of either H+ --> tau+ nubar or H+ --> e+ nubar will be particularly
robust for the spectrum test since they are independent of the unknown Majorana
phases. The H++ decays moderately depend on a Majorana phase Phi2 in the NH,
but sensitively depend on Phi1 in the IH. In a less favorable scenario vd > 2
10^{-4} GeV, when the leptonic channels are suppressed, one needs to observe
the decays H+ --> W+ H_1 and H+ --> t bbar to confirm the triplet-doublet
mixing which in turn implies the existence of the same gauge-invariant
interaction between the lepton doublet and the Higgs triplet responsible for
the neutrino mass generation. In the most optimistic situation, vd approx
10^{-4} GeV, both channels of the lepton pairs and gauge boson pairs may be
available simultaneously. The determination of their relative branching
fractions would give a measurement for the value of vd.
| [
{
"created": "Fri, 23 May 2008 12:19:57 GMT",
"version": "v1"
},
{
"created": "Fri, 27 Jun 2008 12:15:23 GMT",
"version": "v2"
}
] | 2008-07-25 | [
[
"Perez",
"Pavel Fileviez",
""
],
[
"Han",
"Tao",
""
],
[
"Huang",
"Gui-Yu",
""
],
[
"Li",
"Tong",
""
],
[
"Wang",
"Kai",
""
]
] | We demonstrate how to systematically test a well-motivated mechanism for neutrino mass generation (Type-II seesaw) at the LHC, in which a Higgs triplet is introduced. In the optimistic scenarios with a small Higgs triplet vacuum expectation value vd < 10^{-4} GeV, one can look for clean signals of lepton number violation in the decays of doubly charged and singly charged Higgs bosons to distinguish the Normal Hierarchy (NH), the Inverted Hierarchy (IH) and the Quasi-Degenerate (QD) spectrum for the light neutrino masses. The observation of either H+ --> tau+ nubar or H+ --> e+ nubar will be particularly robust for the spectrum test since they are independent of the unknown Majorana phases. The H++ decays moderately depend on a Majorana phase Phi2 in the NH, but sensitively depend on Phi1 in the IH. In a less favorable scenario vd > 2 10^{-4} GeV, when the leptonic channels are suppressed, one needs to observe the decays H+ --> W+ H_1 and H+ --> t bbar to confirm the triplet-doublet mixing which in turn implies the existence of the same gauge-invariant interaction between the lepton doublet and the Higgs triplet responsible for the neutrino mass generation. In the most optimistic situation, vd approx 10^{-4} GeV, both channels of the lepton pairs and gauge boson pairs may be available simultaneously. The determination of their relative branching fractions would give a measurement for the value of vd. |
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