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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1304.3497 | Grigory Ovanesyan | Michael Fickinger, Grigory Ovanesyan, Ivan Vitev | Angular distributions of higher order splitting functions in the vacuum
and in dense QCD matter | 39 pages, 15 pdf figures | null | null | null | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the collinear splitting functions needed for next-to-next-to-leading
order calculations of jet production in the vacuum and in dense QCD matter.
These splitting functions describe the probability of a parton to evolve into
three-parton final state and are generalizations of the traditional DGLAP
splitting kernels to a higher perturbative order. Of particular interest are
the angular distributions of such splitting functions, which can elucidate the
significance of multiple parton branching for jet observables and guide the
construction of parton shower Monte Carlo generators. We find that to ${\cal
O}(\alpha_s^2)$ both the vacuum and the in-medium collinear splitting functions
are neither angular ordered nor anti-angular ordered. Specifically, in dense
QCD matter they retain the characteristic broad angular distribution already
found in the ${\cal O}(\alpha_s)$ result.
| [
{
"created": "Thu, 11 Apr 2013 21:48:05 GMT",
"version": "v1"
}
] | 2013-04-15 | [
[
"Fickinger",
"Michael",
""
],
[
"Ovanesyan",
"Grigory",
""
],
[
"Vitev",
"Ivan",
""
]
] | We study the collinear splitting functions needed for next-to-next-to-leading order calculations of jet production in the vacuum and in dense QCD matter. These splitting functions describe the probability of a parton to evolve into three-parton final state and are generalizations of the traditional DGLAP splitting kernels to a higher perturbative order. Of particular interest are the angular distributions of such splitting functions, which can elucidate the significance of multiple parton branching for jet observables and guide the construction of parton shower Monte Carlo generators. We find that to ${\cal O}(\alpha_s^2)$ both the vacuum and the in-medium collinear splitting functions are neither angular ordered nor anti-angular ordered. Specifically, in dense QCD matter they retain the characteristic broad angular distribution already found in the ${\cal O}(\alpha_s)$ result. |
hep-ph/0112257 | Y. Y. Keum | H.Y. Cheng, Y.-Y. Keum and K.-C. Yang | Angular distribution analysis of $B \to J/\psi K^{*}$ and resolving
discrete ambiguities in the determination of $\phi_1$ | 6 pages, latex with ws-ijmpa.cls, no figures, Talk given at the 3rd
Circum-Pan-Pacific Symposium on High Energy Spin Physics, Bejing, China, 8-13
Oct. 2001 | Int.J.Mod.Phys.A18:1437-1442,2003 | 10.1142/S0217751X0301485X | null | hep-ph | null | We discuss the angular distribution analysis of $B\to J/\psi K^{*}$ decays
and a way to resolve discrete ambiguites in the determination of the unitary
triangle $\phi_1(=\beta)$. We study the status of factorization hypothesis in
the color-suppressed B meson decays: $B\to J/\psi K^{(*)}$ within the general
factorization approach and QCD-factorization method.
| [
{
"created": "Wed, 19 Dec 2001 14:15:49 GMT",
"version": "v1"
}
] | 2010-11-23 | [
[
"Cheng",
"H. Y.",
""
],
[
"Keum",
"Y. -Y.",
""
],
[
"Yang",
"K. -C.",
""
]
] | We discuss the angular distribution analysis of $B\to J/\psi K^{*}$ decays and a way to resolve discrete ambiguites in the determination of the unitary triangle $\phi_1(=\beta)$. We study the status of factorization hypothesis in the color-suppressed B meson decays: $B\to J/\psi K^{(*)}$ within the general factorization approach and QCD-factorization method. |
hep-ph/0301085 | Costas Strouthos | Costas G. Strouthos | Universality in fermionic field theories at finite temperature | 5 pages, Contribution to Conference on Strong and Electroweak Matter
(SEWM2002), Heidelberg, Germany, 2-5 Oct. 2002 | null | 10.1142/9789812704498_0061 | SWAT/02/365 | hep-ph hep-lat | null | We discuss the critical properties of the three-dimensional NJL model at
nonzero temperature. We show that the Z(2)-symmetric model undergoes a second
order phase transition with 2d Ising exponents and its critical region is
suppressed by a factor 1/N^{-0.5}. We also provide numerical evidence that the
U(1)-symmetric model undergoes a BKT transition in accordance with the
dimensional reduction scenario.
| [
{
"created": "Mon, 13 Jan 2003 21:36:33 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Jan 2003 21:42:05 GMT",
"version": "v2"
},
{
"created": "Mon, 27 Jan 2003 19:40:47 GMT",
"version": "v3"
}
] | 2017-08-23 | [
[
"Strouthos",
"Costas G.",
""
]
] | We discuss the critical properties of the three-dimensional NJL model at nonzero temperature. We show that the Z(2)-symmetric model undergoes a second order phase transition with 2d Ising exponents and its critical region is suppressed by a factor 1/N^{-0.5}. We also provide numerical evidence that the U(1)-symmetric model undergoes a BKT transition in accordance with the dimensional reduction scenario. |
0803.3318 | Kenji Fukushima | Kenji Fukushima | Phase diagrams in the three-flavor Nambu--Jona-Lasinio model with the
Polyakov loop | 17 pages, 18 figures, Figure 18 (effect of g_V) replaced as corrected
in Erratum. No change in other results | Phys.Rev.D77:114028,2008; Erratum-ibid.D78:039902,2008 | 10.1103/PhysRevD.77.114028 10.1103/PhysRevD.78.039902 | YITP-08-19 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present extensive studies on hot and dense quark matter with two light and
one heavy flavors in the Nambu--Jona-Lasinio model with the Polyakov loop
(so-called PNJL model). First we discuss prescription dependence in choosing
the Polyakov loop effective potential and propose a simple and rather sensible
ansatz. We look over quantitative comparison to the lattice measurement to
confirm that the model captures thermodynamic properties correctly. We then
analyze the phase structure with changing the temperature, quark chemical
potential, quark masses, and coupling constants. We particularly investigate
how the effective U_A(1) restoration and the induced vector-channel interaction
at finite density would affect the QCD critical point.
| [
{
"created": "Sun, 23 Mar 2008 13:28:56 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Apr 2008 07:03:26 GMT",
"version": "v2"
},
{
"created": "Sat, 26 Jul 2008 07:50:42 GMT",
"version": "v3"
}
] | 2014-11-18 | [
[
"Fukushima",
"Kenji",
""
]
] | We present extensive studies on hot and dense quark matter with two light and one heavy flavors in the Nambu--Jona-Lasinio model with the Polyakov loop (so-called PNJL model). First we discuss prescription dependence in choosing the Polyakov loop effective potential and propose a simple and rather sensible ansatz. We look over quantitative comparison to the lattice measurement to confirm that the model captures thermodynamic properties correctly. We then analyze the phase structure with changing the temperature, quark chemical potential, quark masses, and coupling constants. We particularly investigate how the effective U_A(1) restoration and the induced vector-channel interaction at finite density would affect the QCD critical point. |
1512.06773 | Jonathan Heckman | Jonathan J. Heckman | 750 GeV Diphotons from a D3-brane | v3: 12 pages, 1 figure, clarifications added | null | 10.1016/j.nuclphysb.2016.02.031 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Motivated by the recently reported diphoton excess at 750 GeV observed by
both CMS and ATLAS, we study string-based particle physics models which can
accommodate this signal. Quite remarkably, although Grand Unified Theories in
F-theory tend to impose tight restrictions on candidate extra sectors, the case
of a probe D3-brane near an E-type Yukawa point naturally leads to a class of
strongly coupled models capable of accommodating the observed signature. In
these models, the visible sector is realized by intersecting 7-branes, and the
750 GeV resonance is a scalar modulus associated with motion of the D3-brane in
the direction transverse to the Standard Model 7-branes. Integrating out heavy
3-7 string messenger states leads to dimension five operators for gluon fusion
production and diphoton decays. Due to the unified structure of interactions,
these models also predict that there should be additional decay channels to ZZ
and Z gamma. We also comment on models with distorted unification, where both
the production mechanism and decay channels can differ.
| [
{
"created": "Mon, 21 Dec 2015 19:08:25 GMT",
"version": "v1"
},
{
"created": "Mon, 11 Jan 2016 00:28:31 GMT",
"version": "v2"
},
{
"created": "Wed, 27 Apr 2016 15:32:37 GMT",
"version": "v3"
}
] | 2016-04-28 | [
[
"Heckman",
"Jonathan J.",
""
]
] | Motivated by the recently reported diphoton excess at 750 GeV observed by both CMS and ATLAS, we study string-based particle physics models which can accommodate this signal. Quite remarkably, although Grand Unified Theories in F-theory tend to impose tight restrictions on candidate extra sectors, the case of a probe D3-brane near an E-type Yukawa point naturally leads to a class of strongly coupled models capable of accommodating the observed signature. In these models, the visible sector is realized by intersecting 7-branes, and the 750 GeV resonance is a scalar modulus associated with motion of the D3-brane in the direction transverse to the Standard Model 7-branes. Integrating out heavy 3-7 string messenger states leads to dimension five operators for gluon fusion production and diphoton decays. Due to the unified structure of interactions, these models also predict that there should be additional decay channels to ZZ and Z gamma. We also comment on models with distorted unification, where both the production mechanism and decay channels can differ. |
hep-ph/0409071 | Burkhard Kampfer | J. Cleymans, B. Kampfer, M. Kaneta, S. Wheaton, N. Xu | Centrality Dependence of Thermal Parameters Deduced from Hadron
Multiplicities in Au + Au Collisions at sqrt{s_{NN}} = 130 GeV | null | Phys.Rev.C71:054901,2005 | 10.1103/PhysRevC.71.054901 | null | hep-ph | null | We analyse the centrality dependence of thermal parameters deduced from
hadron m ultiplicities in Au + Au collisions at $\sqrt{s_{NN}} = 130 GeV$.
While the chemical freeze-out temperature and chemical potentials are found to
be roughly centrality-independent, the strangeness saturation factor $\gamma_S$
increases with participant number towards unity, supporting the assumption of
equilibrium freeze-out conditions in central collisions.
| [
{
"created": "Tue, 7 Sep 2004 09:49:59 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Cleymans",
"J.",
""
],
[
"Kampfer",
"B.",
""
],
[
"Kaneta",
"M.",
""
],
[
"Wheaton",
"S.",
""
],
[
"Xu",
"N.",
""
]
] | We analyse the centrality dependence of thermal parameters deduced from hadron m ultiplicities in Au + Au collisions at $\sqrt{s_{NN}} = 130 GeV$. While the chemical freeze-out temperature and chemical potentials are found to be roughly centrality-independent, the strangeness saturation factor $\gamma_S$ increases with participant number towards unity, supporting the assumption of equilibrium freeze-out conditions in central collisions. |
1905.09127 | Steffen Schumann | Enrico Bothmann, Gurpreet Singh Chahal, Stefan H\"oche, Johannes
Krause, Frank Krauss, Silvan Kuttimalai, Sebastian Liebschner, Davide
Napoletano, Marek Sch\"onherr, Holger Schulz, Steffen Schumann, Frank Siegert | Event Generation with Sherpa 2.2 | 39 pages, 18 figures, extended discussion | SciPost Phys. 7, 034 (2019) | 10.21468/SciPostPhys.7.3.034 | FERMILAB-PUB-19-218-T, SLAC-PUB-17433, IPPP/19/42, MCNET-19-11 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Sherpa is a general-purpose Monte Carlo event generator for the simulation of
particle collisions in high-energy collider experiments. We summarize essential
features and improvements of the Sherpa 2.2 release series, which is heavily
used for event generation in the analysis and interpretation of LHC Run 1 and
Run 2 data. We highlight a decade of developments towards ever higher precision
in the simulation of particle-collision events.
| [
{
"created": "Wed, 22 May 2019 13:30:53 GMT",
"version": "v1"
},
{
"created": "Tue, 3 Sep 2019 17:41:38 GMT",
"version": "v2"
}
] | 2019-09-18 | [
[
"Bothmann",
"Enrico",
""
],
[
"Chahal",
"Gurpreet Singh",
""
],
[
"Höche",
"Stefan",
""
],
[
"Krause",
"Johannes",
""
],
[
"Krauss",
"Frank",
""
],
[
"Kuttimalai",
"Silvan",
""
],
[
"Liebschner",
"Sebastian",
""
],
[
"Napoletano",
"Davide",
""
],
[
"Schönherr",
"Marek",
""
],
[
"Schulz",
"Holger",
""
],
[
"Schumann",
"Steffen",
""
],
[
"Siegert",
"Frank",
""
]
] | Sherpa is a general-purpose Monte Carlo event generator for the simulation of particle collisions in high-energy collider experiments. We summarize essential features and improvements of the Sherpa 2.2 release series, which is heavily used for event generation in the analysis and interpretation of LHC Run 1 and Run 2 data. We highlight a decade of developments towards ever higher precision in the simulation of particle-collision events. |
hep-ph/0111265 | Helmut Satz | H. Satz | Matter & More in Nuclear Collisions | 11 pages, 9 figures | null | null | BI-TP 2001/30 | hep-ph | null | The aim of high energy nuclear collisions is to study the transition from
hadronic matter to a plasma of deconfined quarks and gluons. I review the basic
questions of this search and summarize recent theoretical developments in the
field.
| [
{
"created": "Wed, 21 Nov 2001 16:37:13 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Satz",
"H.",
""
]
] | The aim of high energy nuclear collisions is to study the transition from hadronic matter to a plasma of deconfined quarks and gluons. I review the basic questions of this search and summarize recent theoretical developments in the field. |
hep-ph/9912348 | Fabio Benatti | Fabio Benatti, Roberto Floreanini | Direct CP-violation as a test of quantum mechanics | 15 pages, TeX | Eur.Phys.J.C13:267-273,2000 | 10.1007/s100520050692 | null | hep-ph quant-ph | null | Direct CP-violating effects in the neutral kaon system result in violations
of certain Bell-like inequalities. The new experimental results on the
determination of the phenomenological parameter epsilon' allow to dismiss a
large class of ``hidden variable'' alternatives to quantum mechanics.
| [
{
"created": "Wed, 15 Dec 1999 10:06:44 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Benatti",
"Fabio",
""
],
[
"Floreanini",
"Roberto",
""
]
] | Direct CP-violating effects in the neutral kaon system result in violations of certain Bell-like inequalities. The new experimental results on the determination of the phenomenological parameter epsilon' allow to dismiss a large class of ``hidden variable'' alternatives to quantum mechanics. |
hep-ph/9708423 | Vladimir Smirnov | V.A. Smirnov | Asymptotic Expansions of Feynman Integrals on the Mass Shell in Momenta
and Masses | 6 pages, LaTeX, aipproc.sty and axodraw.sty (included), 2 figures;
talk given at the 5th International Conference "Beyond the Standard Model",
Balholm, Norway, April 29 - May 4, 1997 | null | 10.1063/1.54482 | null | hep-ph hep-th | null | A brief review of recent results on asymptotic expansions of Feynman
integrals on the mass shell in momenta and masses and their application to
2-loop calculations is presented.
| [
{
"created": "Thu, 21 Aug 1997 13:27:41 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Smirnov",
"V. A.",
""
]
] | A brief review of recent results on asymptotic expansions of Feynman integrals on the mass shell in momenta and masses and their application to 2-loop calculations is presented. |
2306.02152 | Andrea Beraudo | Andrea Beraudo, Arturo De Pace, Daniel Pablos, Francesco Prino, Marco
Monteno, Marzia Nardi | Heavy-flavor transport and hadronization in pp collisions | null | null | null | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent experimental results on the Lambda_c/D^0 ratio in proton-proton
collisions have revealed a significant enhancement compared to expectations
based on universal fragmentation fractions/functions across different colliding
systems, from e+e- to pp. This unexpected enhancement has sparked speculation
about the potential effects of a deconfined medium impacting hadronization,
previously considered exclusive to heavy-ion collisions. In this study, we
propose a novel approach that assumes the formation of a small, deconfined, and
expanding fireball even in pp collisions, where charm quarks can undergo
rescattering and hadronization. We make use of the same in-medium hadronization
mechanism developed for heavy-ion collisions, which involves local
color-neutralization through recombination of charm quarks with nearby opposite
color charges from the background fireball. Our model incorporates the presence
of diquark excitations in the hot medium, which promotes the formation of
charmed baryons. Moreover, the recombination process, involving closely aligned
partons from the same fluid cell, effectively transfers the collective flow of
the system to the final charmed hadrons. We show that this framework can
qualitatively reproduce the observed experimental findings in heavy-flavor
particle-yield ratios, $p_T$-spectra and elliptic-flow coefficients. Our
results provide new, complementary supporting evidence that the collective
phenomena observed in small systems naturally have the same origin as those
observed in heavy-ion collisions
| [
{
"created": "Sat, 3 Jun 2023 16:40:44 GMT",
"version": "v1"
}
] | 2023-06-06 | [
[
"Beraudo",
"Andrea",
""
],
[
"De Pace",
"Arturo",
""
],
[
"Pablos",
"Daniel",
""
],
[
"Prino",
"Francesco",
""
],
[
"Monteno",
"Marco",
""
],
[
"Nardi",
"Marzia",
""
]
] | Recent experimental results on the Lambda_c/D^0 ratio in proton-proton collisions have revealed a significant enhancement compared to expectations based on universal fragmentation fractions/functions across different colliding systems, from e+e- to pp. This unexpected enhancement has sparked speculation about the potential effects of a deconfined medium impacting hadronization, previously considered exclusive to heavy-ion collisions. In this study, we propose a novel approach that assumes the formation of a small, deconfined, and expanding fireball even in pp collisions, where charm quarks can undergo rescattering and hadronization. We make use of the same in-medium hadronization mechanism developed for heavy-ion collisions, which involves local color-neutralization through recombination of charm quarks with nearby opposite color charges from the background fireball. Our model incorporates the presence of diquark excitations in the hot medium, which promotes the formation of charmed baryons. Moreover, the recombination process, involving closely aligned partons from the same fluid cell, effectively transfers the collective flow of the system to the final charmed hadrons. We show that this framework can qualitatively reproduce the observed experimental findings in heavy-flavor particle-yield ratios, $p_T$-spectra and elliptic-flow coefficients. Our results provide new, complementary supporting evidence that the collective phenomena observed in small systems naturally have the same origin as those observed in heavy-ion collisions |
1404.1585 | Juan Antonio Aguilar-Saavedra | J.A. Aguilar-Saavedra, S. Amor dos Santos | New directions for top quark polarization in the $t$-channel process | LaTeX 6 pages. Minor changes, matches published version | Phys. Rev. D 89, 114009 (2014) | 10.1103/PhysRevD.89.114009 | CERN-PH-TH-2014-086 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We define three orthogonal axes to investigate the top quark polarization in
the $t$-channel single top process. We provide expressions for the polarization
in these axes in terms of anomalous $Wtb$ couplings. It is found that the
polarizations in the two axes orthogonal to the spectator quark axis are very
sensitive to an anomalous coupling involving a $\bar b_L \sigma^{\mu \nu} t_R$
dipole term. In particular, an asymmetry based on the polarization normal to
the production plane is more sensitive to the imaginary part of this coupling
than previously studied observables.
| [
{
"created": "Sun, 6 Apr 2014 15:13:43 GMT",
"version": "v1"
},
{
"created": "Fri, 20 Jun 2014 10:13:47 GMT",
"version": "v2"
}
] | 2014-06-23 | [
[
"Aguilar-Saavedra",
"J. A.",
""
],
[
"Santos",
"S. Amor dos",
""
]
] | We define three orthogonal axes to investigate the top quark polarization in the $t$-channel single top process. We provide expressions for the polarization in these axes in terms of anomalous $Wtb$ couplings. It is found that the polarizations in the two axes orthogonal to the spectator quark axis are very sensitive to an anomalous coupling involving a $\bar b_L \sigma^{\mu \nu} t_R$ dipole term. In particular, an asymmetry based on the polarization normal to the production plane is more sensitive to the imaginary part of this coupling than previously studied observables. |
2306.11416 | John Gracey | J.A. Gracey, R.H. Mason | The Crewther relation, schemes, gauges and fixed points | 51 latex pages, 10 tables, anc directory contains additional tables
and a txt file with the electronic version of results for a general colour
group, minor text changes and additional references | null | null | LTH 1344 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We investigate the Crewther relation at high loop order in a variety of
renormalization schemes and gauges. By examining the properties of the relation
in schemes other than modified minimal subtraction (MSbar) at the fixed points
of Quantum Chromodynamics we propose a generalization of the Crewther relation
that extends the MSbar construction of Broadhurst and Kataev. A derivation
based on the properties of the renormalization group equation is provided for
the generalization which is tested in various scenarios.
| [
{
"created": "Tue, 20 Jun 2023 09:54:48 GMT",
"version": "v1"
},
{
"created": "Thu, 3 Aug 2023 10:52:31 GMT",
"version": "v2"
}
] | 2023-08-04 | [
[
"Gracey",
"J. A.",
""
],
[
"Mason",
"R. H.",
""
]
] | We investigate the Crewther relation at high loop order in a variety of renormalization schemes and gauges. By examining the properties of the relation in schemes other than modified minimal subtraction (MSbar) at the fixed points of Quantum Chromodynamics we propose a generalization of the Crewther relation that extends the MSbar construction of Broadhurst and Kataev. A derivation based on the properties of the renormalization group equation is provided for the generalization which is tested in various scenarios. |
1011.5601 | Pedro Fernando Simoes Costa | C. A. de Sousa, Pedro Costa, M. C. Ruivo, H. Hansen | Phase diagram and critical properties in the
Polyakov--Nambu--Jona-Lasinio model | Talk given at the 9th International Conference on Quark Confinement
and the Hadron Spectrum - QCHS IX, Madrid, Spain, 30 August - September 2010 | AIP Conf.Proc.1343:592,2011 | 10.1063/1.3575104 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the phase diagram of the so-called
Polyakov--Nambu--Jona-Lasinio model at finite temperature and nonzero chemical
potential with three quark flavours. Chiral and deconfinement phase transitions
are discussed, and the relevant order-like parameters are analyzed. The results
are compared with simple thermodynamic expectations and lattice data. A special
attention is payed to the critical end point: as the strength of the
flavour-mixing interaction becomes weaker, the critical end point moves to low
temperatures and can even disappear.
| [
{
"created": "Thu, 25 Nov 2010 11:49:22 GMT",
"version": "v1"
}
] | 2011-06-22 | [
[
"de Sousa",
"C. A.",
""
],
[
"Costa",
"Pedro",
""
],
[
"Ruivo",
"M. C.",
""
],
[
"Hansen",
"H.",
""
]
] | We investigate the phase diagram of the so-called Polyakov--Nambu--Jona-Lasinio model at finite temperature and nonzero chemical potential with three quark flavours. Chiral and deconfinement phase transitions are discussed, and the relevant order-like parameters are analyzed. The results are compared with simple thermodynamic expectations and lattice data. A special attention is payed to the critical end point: as the strength of the flavour-mixing interaction becomes weaker, the critical end point moves to low temperatures and can even disappear. |
hep-ph/0606190 | Antonio Enrique Carcamo Hernandez acarcamo | A. Carcamo, R. Martinez, J.-Alexis Rodriguez | Different kind of textures of Yukawa coupling matrices in the two Higgs
doublet model type III | 14 pages, 1 figure. Added references, corrected typos. Errors
corrected. References added | Eur.Phys.J.C50:935-948,2007 | 10.1140/epjc/s10052-007-0264-0 | null | hep-ph | null | The quark mass matrices ansatze proposed by Fritzsch, Du-Xing and
Fukuyama-Nishiura in the framework of the general two Higgs doublet model are
studied. The corresponding Yukawa matrices in the flavor basis in the different
cases considered are discussed. The corresponding Cabbibo-Kobayashi-Maskawa
matrix elements are computed in all cases and compared with their experimental
values. The complex phases of the ansatze are taken into account and the CP
violating phase $\delta$ is computed. Finally, in order to observe the
influence of the different kind of textures of Yukawa coupling matrices
considered, some phenomenology of two body decays of the top quark, the
lightest Higgs boson and the charged Higgs boson is discussed.
| [
{
"created": "Mon, 19 Jun 2006 03:20:40 GMT",
"version": "v1"
},
{
"created": "Sat, 24 Jun 2006 02:05:38 GMT",
"version": "v2"
},
{
"created": "Tue, 27 Jun 2006 20:39:46 GMT",
"version": "v3"
},
{
"created": "Thu, 22 Mar 2007 17:06:35 GMT",
"version": "v4"
}
] | 2008-11-26 | [
[
"Carcamo",
"A.",
""
],
[
"Martinez",
"R.",
""
],
[
"Rodriguez",
"J. -Alexis",
""
]
] | The quark mass matrices ansatze proposed by Fritzsch, Du-Xing and Fukuyama-Nishiura in the framework of the general two Higgs doublet model are studied. The corresponding Yukawa matrices in the flavor basis in the different cases considered are discussed. The corresponding Cabbibo-Kobayashi-Maskawa matrix elements are computed in all cases and compared with their experimental values. The complex phases of the ansatze are taken into account and the CP violating phase $\delta$ is computed. Finally, in order to observe the influence of the different kind of textures of Yukawa coupling matrices considered, some phenomenology of two body decays of the top quark, the lightest Higgs boson and the charged Higgs boson is discussed. |
hep-ph/0511076 | Johan Bijnens | Johan Bijnens (Lund) | $\eta$ and $\eta'$ decays and what can we learn from them? | 13 pages. Talk presented at the Eta'05 Workshop on production and
decay of $\eta$ and $\eta'$ mesons 15th--18th September 2005, Jagellonian
University, Cracow, Poland. v2 :Changes in figures, misprints corrected,
reference added | ActaPhys.Slov.56:305-318,2006 | null | LU TP 05-42 | hep-ph nucl-th | null | In this talk a short overview of $\eta$ and $\eta'$ decays is given with an
emphasis on what can be learned for the strong interaction from them. The talk
consists of a short introduction to ChPT, a discussion of $\eta\to3\pi$ beyond
$p^4$ and some of the physics involved in $\eta'\to\eta\pi\pi,3\pi$ as well as
an overview of anomalous processes.
| [
{
"created": "Mon, 7 Nov 2005 15:46:46 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Feb 2006 13:13:24 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Bijnens",
"Johan",
"",
"Lund"
]
] | In this talk a short overview of $\eta$ and $\eta'$ decays is given with an emphasis on what can be learned for the strong interaction from them. The talk consists of a short introduction to ChPT, a discussion of $\eta\to3\pi$ beyond $p^4$ and some of the physics involved in $\eta'\to\eta\pi\pi,3\pi$ as well as an overview of anomalous processes. |
1410.5698 | James P. Kneller | James P. Kneller, Neel V. Kabadi | Supernova neutrinos and the turbulence power spectrum: point source
statistics | Matches version accepted by PRD | Phys. Rev. D 92, 013009 (2015) | 10.1103/PhysRevD.92.013009 | null | hep-ph astro-ph.SR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The neutrinos emitted from the proto-neutron star created in a core-collapse
supernova must run through a significant amount of turbulence before exiting
the star. Turbulence can modify the flavor evolution of the neutrinos
imprinting itself upon the signal detected here at Earth. The turbulence effect
upon individual neutrinos, and the correlation between pairs of neutrinos,
might exhibit sensitivity to the power spectrum of the turbulence and recent
analysis of the turbulence in a two-dimensional hydrodynamical simulation of a
core-collapse supernova indicates the power spectrum may not be the Kolmogorov
5/3 inverse power law as has been previously assumed. In this paper we study
the effect of non-Kolmogorov turbulence power spectra upon neutrinos from a
point source as a function of neutrino energy and turbulence amplitude at a
fixed post-bounce epoch. We find the two effects of turbulence upon the
neutrinos - the distorted phase effect and the stimulated transitions - both
possess strong and weak limits in which dependence upon the power spectrum is
absent or evident respectively. Since neutrinos of a given energy will exhibit
these two effects at different epochs of the supernova each with evolving
strength, we find there is sensitivity to the power spectrum present in the
neutrino burst signal from a Galactic supernova.
| [
{
"created": "Tue, 21 Oct 2014 15:10:14 GMT",
"version": "v1"
},
{
"created": "Mon, 6 Jul 2015 12:33:26 GMT",
"version": "v2"
}
] | 2015-07-22 | [
[
"Kneller",
"James P.",
""
],
[
"Kabadi",
"Neel V.",
""
]
] | The neutrinos emitted from the proto-neutron star created in a core-collapse supernova must run through a significant amount of turbulence before exiting the star. Turbulence can modify the flavor evolution of the neutrinos imprinting itself upon the signal detected here at Earth. The turbulence effect upon individual neutrinos, and the correlation between pairs of neutrinos, might exhibit sensitivity to the power spectrum of the turbulence and recent analysis of the turbulence in a two-dimensional hydrodynamical simulation of a core-collapse supernova indicates the power spectrum may not be the Kolmogorov 5/3 inverse power law as has been previously assumed. In this paper we study the effect of non-Kolmogorov turbulence power spectra upon neutrinos from a point source as a function of neutrino energy and turbulence amplitude at a fixed post-bounce epoch. We find the two effects of turbulence upon the neutrinos - the distorted phase effect and the stimulated transitions - both possess strong and weak limits in which dependence upon the power spectrum is absent or evident respectively. Since neutrinos of a given energy will exhibit these two effects at different epochs of the supernova each with evolving strength, we find there is sensitivity to the power spectrum present in the neutrino burst signal from a Galactic supernova. |
hep-ph/0306119 | Stefano Profumo | Stefano Profumo | Neutralino relic density in supersymmetric GUTs with no-scale boundary
conditions above the unification scale | 14 pages, 5 figures, JHEP style. Version accepted for publication in
JHEP | JHEP0306:052,2003 | 10.1088/1126-6708/2003/06/052 | SISSA-49/2003/EP | hep-ph astro-ph hep-th | null | We investigate SU(5) and SO(10) GUTs with vanishing scalar masses and
trilinear scalar couplings at a scale higher than the unification scale. The
parameter space of the models, further constrained by b-\tau Yukawa coupling
unification, consists of a common gaugino mass and of \tan\beta. We analyze the
low energy phenomenology, finding that A-pole annihilations of neutralinos
and/or coannihilations with the lightest stau drive the relic density within
the cosmologically preferred range in a significant region of the allowed
parameter space. Implications for neutralino direct detection and for CERN LHC
experiments are also discussed.
| [
{
"created": "Fri, 13 Jun 2003 11:07:08 GMT",
"version": "v1"
},
{
"created": "Thu, 26 Jun 2003 17:09:42 GMT",
"version": "v2"
}
] | 2009-11-10 | [
[
"Profumo",
"Stefano",
""
]
] | We investigate SU(5) and SO(10) GUTs with vanishing scalar masses and trilinear scalar couplings at a scale higher than the unification scale. The parameter space of the models, further constrained by b-\tau Yukawa coupling unification, consists of a common gaugino mass and of \tan\beta. We analyze the low energy phenomenology, finding that A-pole annihilations of neutralinos and/or coannihilations with the lightest stau drive the relic density within the cosmologically preferred range in a significant region of the allowed parameter space. Implications for neutralino direct detection and for CERN LHC experiments are also discussed. |
hep-ph/9609283 | Lu Gong Ru | Gongru Lu, Yigang Cao, Zhaohua Xiong, Chongxing Yue and Zhenjun Xiao | Multiscale Technicolor and $b \to s \gamma$ | 11 pages, Latex, no macros, 3 figures, hard copy is available upon
request. to appear in Z. Phys. C | Z.Phys.C74:355-358,1997 | 10.1007/s002880050397 | HNU-TH-96/9 | hep-ph | null | Correction to the $b\rightarrow s\gamma$ branching ratio in the multiscale
walking technicolor model (MWTCM) is examined. For the original MWTCM, the
correction is too large to explain the recent CLEO data. We show that if
topcolor is further introduced, the branching ratio in the topcolor assisted
MWTCM can be in agreement with the CLEO data for a certain range of the
parameters.
| [
{
"created": "Sat, 7 Sep 1996 08:37:23 GMT",
"version": "v1"
}
] | 2008-12-25 | [
[
"Lu",
"Gongru",
""
],
[
"Cao",
"Yigang",
""
],
[
"Xiong",
"Zhaohua",
""
],
[
"Yue",
"Chongxing",
""
],
[
"Xiao",
"Zhenjun",
""
]
] | Correction to the $b\rightarrow s\gamma$ branching ratio in the multiscale walking technicolor model (MWTCM) is examined. For the original MWTCM, the correction is too large to explain the recent CLEO data. We show that if topcolor is further introduced, the branching ratio in the topcolor assisted MWTCM can be in agreement with the CLEO data for a certain range of the parameters. |
0712.3447 | Celso de Camargo Barros Jr. | Celso de Camargo Barros Jr. and Yogiro Hama | Lambda and Antilambda polarization in Au-Au collisions at RHIC | null | Phys.Lett.B699:74-77,2011 | 10.1016/j.physletb.2011.03.052 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent experiments at RHIC have shown that in 200 GeV Au-Au collisions, the
Lambda and Antilambda hyperons are produced with very small polarizations [1],
almost consistent with zero. These results can be understood in terms of a
model that we recently proposed [2]. In this work, we show how this model may
be applied in such collisions, and also will discuss the relation of our
results with other models, in order to explain the experimental data.
| [
{
"created": "Thu, 20 Dec 2007 15:08:34 GMT",
"version": "v1"
},
{
"created": "Wed, 2 Jun 2010 21:21:35 GMT",
"version": "v2"
}
] | 2011-04-20 | [
[
"Barros",
"Celso de Camargo",
"Jr."
],
[
"Hama",
"Yogiro",
""
]
] | Recent experiments at RHIC have shown that in 200 GeV Au-Au collisions, the Lambda and Antilambda hyperons are produced with very small polarizations [1], almost consistent with zero. These results can be understood in terms of a model that we recently proposed [2]. In this work, we show how this model may be applied in such collisions, and also will discuss the relation of our results with other models, in order to explain the experimental data. |
0809.2823 | Bogdan Malaescu I. | Bogdan Malaescu | Precise alpha_s from Tau Decays | 4 pages, 2 figures. To appear in the proceedings of QCD08,
Montpellier, France, 7-12th July 2008 | Nucl.Phys.Proc.Suppl.186:183-186,2009 | 10.1016/j.nuclphysbps.2008.12.043 | LAL 08-159 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An updated measurement of alpha_s(m_tau) from ALEPH tau hadronic spectral
functions is presented. We report a study of the perturbative prediction(s)
showing that the fixed-order perturbation theory manifests convergence or
principle problems not presented in the contour-improved calculation. Potential
systematic effects from quark-hadron duality violations are estimated to be
within the quoted systematic errors. The fit result is alpha_s(m_tau) = 0.344
+- 0.005 +- 0.007, where the first error is experimental and the second
theoretical. After evolution, the alpha_s(M_Z) determined from tau data is one
of the most precise to date, in agreement with the corresponding NNNLO value
derived from Z decays.
| [
{
"created": "Tue, 16 Sep 2008 22:21:15 GMT",
"version": "v1"
},
{
"created": "Mon, 10 Nov 2008 12:00:10 GMT",
"version": "v2"
}
] | 2010-04-21 | [
[
"Malaescu",
"Bogdan",
""
]
] | An updated measurement of alpha_s(m_tau) from ALEPH tau hadronic spectral functions is presented. We report a study of the perturbative prediction(s) showing that the fixed-order perturbation theory manifests convergence or principle problems not presented in the contour-improved calculation. Potential systematic effects from quark-hadron duality violations are estimated to be within the quoted systematic errors. The fit result is alpha_s(m_tau) = 0.344 +- 0.005 +- 0.007, where the first error is experimental and the second theoretical. After evolution, the alpha_s(M_Z) determined from tau data is one of the most precise to date, in agreement with the corresponding NNNLO value derived from Z decays. |
1102.2844 | Alan D. Martin | M. G. Ryskin, A.D. Martin and V.A. Khoze | High-energy strong interactions: from `hard' to `soft' | 36 pages, 12 figures. Version published in EPJC which has captions to
Figs. 8 and 9 corrected | null | 10.1140/epjc/s10052-011-1617-2 | IPPP/11/10, DCPT/11/20 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the qualitative features of the recent data on multiparticle
production observed at the LHC. The tolerable agreement with Monte Carlos based
on LO DGLAP evolution indicates that there is no qualitative difference between
`hard' and `soft' interactions; and that a perturbative QCD approach may be
extended into the soft domain. However, in order to describe the data, these
Monte Carlos need an additional infrared cutoff k_min with a value k_min ~ 2-3
GeV which is not small, and which increases with collider energy. Here we
explain the physical origin of the large k_min. Using an alternative model
which matches the `soft' high-energy hadron interactions smoothly on to
perturbative QCD at small x, we demonstrate that this effective cutoff k_min is
actually due to the strong absorption of low k_t partons. The model embodies
the main features of the BFKL approach, including the diffusion in transverse
momenta, lnk_t, and an intercept consistent with resummed next-to-leading log
corrections. Moreover, the model uses a two-channel eikonal framework, and
includes the contributions from the multi-Pomeron exchange diagrams, both
non-enhanced and enhanced. The values of a small number of physically-motivated
parameters are chosen to reproduce the available total, elastic and proton
dissociation cross section (pre-LHC) data. Predictions are made for the LHC,
and the relevance to ultra-high-energy cosmic rays is briefly discussed. The
low x inclusive integrated gluon PDF, and the diffractive gluon PDF, are
calculated in this framework, using the parameters which describe the
high-energy pp and p\bar{p} `soft' data. Comparison with the PDFs obtained from
the global parton analyses of deep inelastic and related `hard' scattering
data, and from diffractive deep inelastic data looks encouraging.
| [
{
"created": "Mon, 14 Feb 2011 18:15:37 GMT",
"version": "v1"
},
{
"created": "Mon, 2 May 2011 16:23:52 GMT",
"version": "v2"
}
] | 2015-05-27 | [
[
"Ryskin",
"M. G.",
""
],
[
"Martin",
"A. D.",
""
],
[
"Khoze",
"V. A.",
""
]
] | We discuss the qualitative features of the recent data on multiparticle production observed at the LHC. The tolerable agreement with Monte Carlos based on LO DGLAP evolution indicates that there is no qualitative difference between `hard' and `soft' interactions; and that a perturbative QCD approach may be extended into the soft domain. However, in order to describe the data, these Monte Carlos need an additional infrared cutoff k_min with a value k_min ~ 2-3 GeV which is not small, and which increases with collider energy. Here we explain the physical origin of the large k_min. Using an alternative model which matches the `soft' high-energy hadron interactions smoothly on to perturbative QCD at small x, we demonstrate that this effective cutoff k_min is actually due to the strong absorption of low k_t partons. The model embodies the main features of the BFKL approach, including the diffusion in transverse momenta, lnk_t, and an intercept consistent with resummed next-to-leading log corrections. Moreover, the model uses a two-channel eikonal framework, and includes the contributions from the multi-Pomeron exchange diagrams, both non-enhanced and enhanced. The values of a small number of physically-motivated parameters are chosen to reproduce the available total, elastic and proton dissociation cross section (pre-LHC) data. Predictions are made for the LHC, and the relevance to ultra-high-energy cosmic rays is briefly discussed. The low x inclusive integrated gluon PDF, and the diffractive gluon PDF, are calculated in this framework, using the parameters which describe the high-energy pp and p\bar{p} `soft' data. Comparison with the PDFs obtained from the global parton analyses of deep inelastic and related `hard' scattering data, and from diffractive deep inelastic data looks encouraging. |
1502.02497 | Zhun Lu | Wenjuan Mao, Xiaoyu Wang, Xiaozhen Du, Zhun Lu, Bo-Qiang Ma | A phenomenological study on the $\cos\phi_h$ azimuthal asymmetry in
double longitudinally Polarized SIDIS | 7 pages,8 figures | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the $\cos{\phi_h}$ azimuthal asymmetry in double polarized
semi-inclusive pion production by considering dynamical twist-3 effects. In
particular, we evaluate the role of the transverse momentum dependent
distributions $e_L(x, k_T^2)$ and $g_L^\perp(x, k_T^2)$ on the asymmetry. Using
two different sets of spectator model results for these distributions, we
predict the $\cos{\phi_h}$ asymmetry of $\pi^+$, $\pi^-$, and $\pi^0$ at the
kinematic configuration available at CLAS, HERMES and COMPASS. Our estimates
show that the asymmetries are positive for all the pions and could be accessed
by CLAS and HERMES. We also find that $g_L^\perp$ gives the dominant
contribution to the $\cos\phi_h$ asymmetry, while the contribution of $e_L$ is
almost negligible.
| [
{
"created": "Mon, 9 Feb 2015 14:30:29 GMT",
"version": "v1"
}
] | 2015-02-10 | [
[
"Mao",
"Wenjuan",
""
],
[
"Wang",
"Xiaoyu",
""
],
[
"Du",
"Xiaozhen",
""
],
[
"Lu",
"Zhun",
""
],
[
"Ma",
"Bo-Qiang",
""
]
] | We study the $\cos{\phi_h}$ azimuthal asymmetry in double polarized semi-inclusive pion production by considering dynamical twist-3 effects. In particular, we evaluate the role of the transverse momentum dependent distributions $e_L(x, k_T^2)$ and $g_L^\perp(x, k_T^2)$ on the asymmetry. Using two different sets of spectator model results for these distributions, we predict the $\cos{\phi_h}$ asymmetry of $\pi^+$, $\pi^-$, and $\pi^0$ at the kinematic configuration available at CLAS, HERMES and COMPASS. Our estimates show that the asymmetries are positive for all the pions and could be accessed by CLAS and HERMES. We also find that $g_L^\perp$ gives the dominant contribution to the $\cos\phi_h$ asymmetry, while the contribution of $e_L$ is almost negligible. |
2306.12953 | Shao-Feng Ge | Shao-Feng Ge and Pedro Pasquini | Disentangle Neutrino Electromagnetic Properties with Atomic Radiative
Pair Emission | 32 pages, 4 figures, matches with the JHEP version | null | 10.1007/JHEP12(2023)083 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We elaborate the possibility of using the atomic radiative emission of
neutrino pair (RENP) to probe the neutrino electromagnetic properties,
including magnetic and electric dipole moments, charge radius, and anapole.
With the typical O(eV) momentum transfer, the atomic RENP is sensitive to not
just the tiny neutrino masses but also very light mediators to which the
massless photon belongs. The neutrino EM properties introduce extra
contribution besides the SM one induced by the heavy W/Z gauge bosons. Since
the associated photon spectrum is divided into several sections whose
boundaries are determined by the final-state neutrino masses, it is possible to
identify the individual neutrino EM form factor elements. Most importantly,
scanning the photon spectrum inside the particular section with deviation from
the SM prediction once observed allows identification of the neutrino EM form
factor type. The RENP provides an ultimate way of disentangling the neutrino EM
properties to go beyond the current experimental searches or observations.
| [
{
"created": "Thu, 22 Jun 2023 15:12:10 GMT",
"version": "v1"
},
{
"created": "Thu, 21 Dec 2023 12:53:53 GMT",
"version": "v2"
}
] | 2023-12-22 | [
[
"Ge",
"Shao-Feng",
""
],
[
"Pasquini",
"Pedro",
""
]
] | We elaborate the possibility of using the atomic radiative emission of neutrino pair (RENP) to probe the neutrino electromagnetic properties, including magnetic and electric dipole moments, charge radius, and anapole. With the typical O(eV) momentum transfer, the atomic RENP is sensitive to not just the tiny neutrino masses but also very light mediators to which the massless photon belongs. The neutrino EM properties introduce extra contribution besides the SM one induced by the heavy W/Z gauge bosons. Since the associated photon spectrum is divided into several sections whose boundaries are determined by the final-state neutrino masses, it is possible to identify the individual neutrino EM form factor elements. Most importantly, scanning the photon spectrum inside the particular section with deviation from the SM prediction once observed allows identification of the neutrino EM form factor type. The RENP provides an ultimate way of disentangling the neutrino EM properties to go beyond the current experimental searches or observations. |
2102.12591 | Jesse Giron | Justin M. Gens, Jesse F. Giron, Richard F. Lebed | Radiative Transitions of Charmoniumlike Exotics in the Dynamical Diquark
Model | 10 pages, Version accepted for publication at Phys. Rev. D. Includes
calculations beyond long-wavelength limit | Phys. Rev. D 103, 094024 (2021) | 10.1103/PhysRevD.103.094024 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Using the dynamical diquark model, we calculate the electric-dipole radiative
decay widths to $X(3872)$ of the lightest negative-parity exotic candidates,
including the four $I=0$, $J^{PC} \! = \! 1^{--}$ ("$Y$") states. The
$O$(100--1000 keV) values obtained test the hypothesis of a common substructure
shared by all of these states. We also calculate the magnetic-dipole radiative
decay width for $Z_c(4020)^0 \! \to \! \gamma X(3872)$, and find it to be
rather smaller ($<$~10 keV) than its predicted value in molecular models.
| [
{
"created": "Wed, 24 Feb 2021 22:39:04 GMT",
"version": "v1"
},
{
"created": "Tue, 20 Apr 2021 02:03:01 GMT",
"version": "v2"
}
] | 2021-05-26 | [
[
"Gens",
"Justin M.",
""
],
[
"Giron",
"Jesse F.",
""
],
[
"Lebed",
"Richard F.",
""
]
] | Using the dynamical diquark model, we calculate the electric-dipole radiative decay widths to $X(3872)$ of the lightest negative-parity exotic candidates, including the four $I=0$, $J^{PC} \! = \! 1^{--}$ ("$Y$") states. The $O$(100--1000 keV) values obtained test the hypothesis of a common substructure shared by all of these states. We also calculate the magnetic-dipole radiative decay width for $Z_c(4020)^0 \! \to \! \gamma X(3872)$, and find it to be rather smaller ($<$~10 keV) than its predicted value in molecular models. |
hep-ph/9904454 | Guetta Dafne | Dafne Guetta and Paul Singer | Two photon decays of heavy vector mesons, $B^{*}\to B\gamma
\gamma$,$D^{*}\to D\gamma \gamma$, and the possible determination of the
$g_{B^{*}(D^{*})B(D)\pi}$ and $g_{{B^{*}}^0B^0\gamma}$ couplings | 22 pages, LaTeX, 5 ps-figures (uses subfigure.sty). Accepted by Phys.
Rev. D | Phys.Rev. D61 (2000) 054014 | 10.1103/PhysRevD.61.054014 | null | hep-ph | null | We study the novel decays $B^{*}\to B\gamma\gamma $ and $D^{*}\to D\gamma
\gamma $ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L)
to leading order in chiral perturbation theory. The branching ratios of these
decays are expressed in terms of the strong $g_{B^{*}(D^{*})B(D)\pi}$ and the
electromagnetic $g_{B^{*}(D^*)B(D)\gamma}$ couplings, thus providing a possible
tool for their determination. In the charm case, using the experimentally
determined ratios $({D^*}^{0,+}\to D\pi)/({D^*}^{0,+}\to D\gamma),$ we are able
to express the branching ratio as a function of the strong coupling only. We
thus find $1.6\times 10^{-6}<{\rm Br} ({D^{*}}^{0}\to
D^0\gamma\gamma)<3.3\times 10^{-5}$ for $0.25<g<1,$ where $g$ is the strong
coupling of HM$\chi$L. In the beauty sector, the ${\rm Br}({B^{*}}^{0} \to B^0
\gamma\gamma)$ which we estimate to be in the $10^{-7}-10^{-5}$ range is a
function of both $g_{B^{*}B\pi}$ and $g_{B^{*}B\gamma}.$ Its behaviour does not
afford an unambiguous determination of these couplings except for the region of
high $g$ values like $g>0.6.$ The expected two-photon differential
distributions are presented for both ${B^{*}}^{0} \to B^0 \gamma\gamma$ and
${D^{*}}^{0}\to D^0\gamma\gamma,$ for different values of the couplings
involved.
| [
{
"created": "Mon, 26 Apr 1999 16:34:38 GMT",
"version": "v1"
},
{
"created": "Thu, 28 Oct 1999 12:24:48 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Guetta",
"Dafne",
""
],
[
"Singer",
"Paul",
""
]
] | We study the novel decays $B^{*}\to B\gamma\gamma $ and $D^{*}\to D\gamma \gamma $ using the framework of the Heavy Meson Chiral Lagrangian (HM$\chi$L) to leading order in chiral perturbation theory. The branching ratios of these decays are expressed in terms of the strong $g_{B^{*}(D^{*})B(D)\pi}$ and the electromagnetic $g_{B^{*}(D^*)B(D)\gamma}$ couplings, thus providing a possible tool for their determination. In the charm case, using the experimentally determined ratios $({D^*}^{0,+}\to D\pi)/({D^*}^{0,+}\to D\gamma),$ we are able to express the branching ratio as a function of the strong coupling only. We thus find $1.6\times 10^{-6}<{\rm Br} ({D^{*}}^{0}\to D^0\gamma\gamma)<3.3\times 10^{-5}$ for $0.25<g<1,$ where $g$ is the strong coupling of HM$\chi$L. In the beauty sector, the ${\rm Br}({B^{*}}^{0} \to B^0 \gamma\gamma)$ which we estimate to be in the $10^{-7}-10^{-5}$ range is a function of both $g_{B^{*}B\pi}$ and $g_{B^{*}B\gamma}.$ Its behaviour does not afford an unambiguous determination of these couplings except for the region of high $g$ values like $g>0.6.$ The expected two-photon differential distributions are presented for both ${B^{*}}^{0} \to B^0 \gamma\gamma$ and ${D^{*}}^{0}\to D^0\gamma\gamma,$ for different values of the couplings involved. |
hep-ph/0611146 | Holger Gies | Holger Gies (Heidelberg U.) | Introduction to the functional RG and applications to gauge theories | 60 pages, 14 figures, Lectures held at the 2006 ECT* School
"Renormalization Group and Effective Field Theory Approaches to Many-Body
Systems", Trento, Italy | null | 10.1007/978-3-642-27320-9_6 | null | hep-ph | null | These lectures contain an introduction to modern renormalization group (RG)
methods as well as functional RG approaches to gauge theories. In the first
lecture, the functional renormalization group is introduced with a focus on the
flow equation for the effective average action. The second lecture is devoted
to a discussion of flow equations and symmetries in general, and flow equations
and gauge symmetries in particular. The third lecture deals with the flow
equation in the background formalism which is particularly convenient for
analytical computations of truncated flows. The fourth lecture concentrates on
the transition from microscopic to macroscopic degrees of freedom; even though
this is discussed here in the language and the context of QCD, the developed
formalism is much more general and will be useful also for other systems.
| [
{
"created": "Fri, 10 Nov 2006 15:55:38 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Gies",
"Holger",
"",
"Heidelberg U."
]
] | These lectures contain an introduction to modern renormalization group (RG) methods as well as functional RG approaches to gauge theories. In the first lecture, the functional renormalization group is introduced with a focus on the flow equation for the effective average action. The second lecture is devoted to a discussion of flow equations and symmetries in general, and flow equations and gauge symmetries in particular. The third lecture deals with the flow equation in the background formalism which is particularly convenient for analytical computations of truncated flows. The fourth lecture concentrates on the transition from microscopic to macroscopic degrees of freedom; even though this is discussed here in the language and the context of QCD, the developed formalism is much more general and will be useful also for other systems. |
hep-ph/0311183 | N. D. Tracas | N.D. Tracas (Physics Department, NTU Athens) | GUT Precursors in $SU(3)^3$-Type Model and $N_{COLOUR}>3$ | 8pages, 3 Postscript figures, graphicx.sty | Mod.Phys.Lett.A19:1615-1622,2004 | 10.1142/S0217732304013878 | null | hep-ph | null | We investigate the $SU(3)^3$ GUT model when signs of the model (precursors),
due to low compactification scale, appear before the gauge couplings of the
Standard Model get unified. The Kaluza-Klein state contribution seems to lead
the gauge couplings to unification through a wide energy scale only in the case
when the colour group is augmented to SU(4).
| [
{
"created": "Fri, 14 Nov 2003 09:57:39 GMT",
"version": "v1"
}
] | 2011-02-18 | [
[
"Tracas",
"N. D.",
"",
"Physics Department, NTU Athens"
]
] | We investigate the $SU(3)^3$ GUT model when signs of the model (precursors), due to low compactification scale, appear before the gauge couplings of the Standard Model get unified. The Kaluza-Klein state contribution seems to lead the gauge couplings to unification through a wide energy scale only in the case when the colour group is augmented to SU(4). |
hep-ph/9608253 | Please Reply To | T.K. Gaisser, M. Honda, K. Kasahara, H. Lee, S. Midorikawa, V. Naumov
and Todor Stanev | Comparison of Atmospheric Neutrino Flux Calculations at Low Energies | 15 pages, RevTeX , 5 postscript figures, submitted to Phys. Rev. D | Phys.Rev.D54:5578-5584,1996 | 10.1103/PhysRevD.54.5578 | BRI-96-19 | hep-ph | null | We compare several different calculations of the atmospheric neutrino flux in
the energy range relevant for contained neutrino interactions, and we identify
the major sources of difference among the calculations. We find nothing that
would affect the predicted ratio of $\nu_e/\nu_\mu$, which is nearly the same
in all calculations. Significant differences in normalization arise primarily
from different treatment of pion production by interactions of protons in the
atmosphere. Different assumptions about the primary spectrum and treatment of
the geomagnetic field are also of some importance.
| [
{
"created": "Wed, 7 Aug 1996 17:43:39 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Gaisser",
"T. K.",
""
],
[
"Honda",
"M.",
""
],
[
"Kasahara",
"K.",
""
],
[
"Lee",
"H.",
""
],
[
"Midorikawa",
"S.",
""
],
[
"Naumov",
"V.",
""
],
[
"Stanev",
"Todor",
""
]
] | We compare several different calculations of the atmospheric neutrino flux in the energy range relevant for contained neutrino interactions, and we identify the major sources of difference among the calculations. We find nothing that would affect the predicted ratio of $\nu_e/\nu_\mu$, which is nearly the same in all calculations. Significant differences in normalization arise primarily from different treatment of pion production by interactions of protons in the atmosphere. Different assumptions about the primary spectrum and treatment of the geomagnetic field are also of some importance. |
1401.6012 | Florian Lyonnet | T. Je\v{z}o, M. Klasen, F. Lyonnet, F. Montanet, I. Schienbein, M.
Tartare | Can new heavy gauge bosons be observed in ultra-high energy cosmic
neutrino events? | 5 pages, 2 figures | Phys.Rev. D89 (2014) 077702 | 10.1103/PhysRevD.89.077702 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A wide range of models beyond the Standard Model predict charged and neutral
resonances, generically called $W'$- and $Z'$-bosons, respectively. In this
paper we study the impact of such resonances on the deep inelastic scattering
of ultra-high energy neutrinos as well as on the resonant charged current
$\bar\nu_e e^-$ scattering (Glashow resonance). We find that the effects of
such resonances can not be observed with the Pierre Auger Observatory or any
foreseeable upgrade of it.
| [
{
"created": "Thu, 23 Jan 2014 15:44:10 GMT",
"version": "v1"
}
] | 2014-05-15 | [
[
"Ježo",
"T.",
""
],
[
"Klasen",
"M.",
""
],
[
"Lyonnet",
"F.",
""
],
[
"Montanet",
"F.",
""
],
[
"Schienbein",
"I.",
""
],
[
"Tartare",
"M.",
""
]
] | A wide range of models beyond the Standard Model predict charged and neutral resonances, generically called $W'$- and $Z'$-bosons, respectively. In this paper we study the impact of such resonances on the deep inelastic scattering of ultra-high energy neutrinos as well as on the resonant charged current $\bar\nu_e e^-$ scattering (Glashow resonance). We find that the effects of such resonances can not be observed with the Pierre Auger Observatory or any foreseeable upgrade of it. |
1807.10798 | Martin Schumacher | Martin Schumacher | Mass and structure of the nucleon: Gluon trace anomaly versus
spontaneous symmetry breaking | 7 pages, 1 figure | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Two different approaches to mass and structure of the nucleon are discussed
in recent works, ${\it viz.}$ (case 1) the QCD lagrangian evaluated via lattice
calculations and (case ii) spontaneous symmetry breaking mediated by the
$\sigma$ field. These approaches are complementary in the sense that the QCD
lagrangian makes use of the gluon content of the nucleon entering in terms of
the gluon trace-anomaly and ignores the effects of $q{\bar q}$ vacuum
polarization, whereas in spontaneous symmetry breaking masses are formed by
attaching $q{\bar q}$ pairs to the valence quarks, thus giving them a definite
mass which is named the constituent mass. By the same process the $q{\bar q}$
pairs of the vacuum polarization acquire mass and in this form are the elements
of the quark condensate, having an up-quark and a down-quark component. A
linear combination of these two components in the form
$\sigma=1/\sqrt{2}(u{\bar u} + d{\bar d})$ shows up as the $\sigma$ field. It
is shown that (case i) corresponds to an unstable nucleon configuration whereas
(case ii) corresponds to a stable nucleon configuration as observed in
low-energy photo-nuclear and pion-nuclear reactions.
| [
{
"created": "Fri, 27 Jul 2018 18:56:17 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Oct 2018 13:03:23 GMT",
"version": "v2"
},
{
"created": "Fri, 23 Aug 2019 08:59:37 GMT",
"version": "v3"
}
] | 2019-08-26 | [
[
"Schumacher",
"Martin",
""
]
] | Two different approaches to mass and structure of the nucleon are discussed in recent works, ${\it viz.}$ (case 1) the QCD lagrangian evaluated via lattice calculations and (case ii) spontaneous symmetry breaking mediated by the $\sigma$ field. These approaches are complementary in the sense that the QCD lagrangian makes use of the gluon content of the nucleon entering in terms of the gluon trace-anomaly and ignores the effects of $q{\bar q}$ vacuum polarization, whereas in spontaneous symmetry breaking masses are formed by attaching $q{\bar q}$ pairs to the valence quarks, thus giving them a definite mass which is named the constituent mass. By the same process the $q{\bar q}$ pairs of the vacuum polarization acquire mass and in this form are the elements of the quark condensate, having an up-quark and a down-quark component. A linear combination of these two components in the form $\sigma=1/\sqrt{2}(u{\bar u} + d{\bar d})$ shows up as the $\sigma$ field. It is shown that (case i) corresponds to an unstable nucleon configuration whereas (case ii) corresponds to a stable nucleon configuration as observed in low-energy photo-nuclear and pion-nuclear reactions. |
2309.07583 | Nivedita Ghosh | Nivedita Ghosh, Santosh Kumar Rai, and Tousik Samui | Search For a Leptoquark and Vector-like Lepton in a Muon Collider | 27 pages, 4 figures, and 3 tables, version accepted for publication
in Nuclear Physics B journal | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The proposal for a high-energy muon collider offers many opportunities in the
search for physics beyond the Standard Model (BSM). The collider by
construction is likely to be more sensitive to the muon-philic models,
primarily motivated by the BSM explanation of muon $(g-2)$ excess and quark
flavor anomalies. In this work, we explore the potential of the proposed muon
collider in the context of such models and focus on one such model that extends
the Standard Model (SM) with a leptoquark, a vector-like lepton, and a real
scalar. In this model, we propose searches for TeV scale leptoquarks in
$2\mu+2b+mET$ channel. Notably, the leptoquark can be produced singly at the
muon collider with a large cross-section. We have shown that a significant
signal in this channel can be detected at a 3~TeV muon collider even with an
integrated luminosity as low as $\sim 10$~fb$^{-1}$
| [
{
"created": "Thu, 14 Sep 2023 10:28:52 GMT",
"version": "v1"
},
{
"created": "Sun, 12 May 2024 05:18:16 GMT",
"version": "v2"
}
] | 2024-05-14 | [
[
"Ghosh",
"Nivedita",
""
],
[
"Rai",
"Santosh Kumar",
""
],
[
"Samui",
"Tousik",
""
]
] | The proposal for a high-energy muon collider offers many opportunities in the search for physics beyond the Standard Model (BSM). The collider by construction is likely to be more sensitive to the muon-philic models, primarily motivated by the BSM explanation of muon $(g-2)$ excess and quark flavor anomalies. In this work, we explore the potential of the proposed muon collider in the context of such models and focus on one such model that extends the Standard Model (SM) with a leptoquark, a vector-like lepton, and a real scalar. In this model, we propose searches for TeV scale leptoquarks in $2\mu+2b+mET$ channel. Notably, the leptoquark can be produced singly at the muon collider with a large cross-section. We have shown that a significant signal in this channel can be detected at a 3~TeV muon collider even with an integrated luminosity as low as $\sim 10$~fb$^{-1}$ |
hep-ph/0611326 | Sven Heinemeyer | M. Frank, T. Hahn, S. Heinemeyer, W. Hollik, H. Rzehak, G. Weiglein | The Higgs Boson Masses and Mixings of the Complex MSSM in the
Feynman-Diagrammatic Approach | 57 pages, 12 figures. Discussion about decoupling properties added,
references added. Version to appear in JHEP | JHEP 0702:047,2007 | 10.1088/1126-6708/2007/02/047 | DCPT/06/160, IPPP/06/80, MPP-2006-158, PSI-PR-06-14 | hep-ph | null | New results for the complete one-loop contributions to the masses and mixing
effects in the Higgs sector are obtained for the MSSM with complex parameters
using the Feynman-diagrammatic approach. The full dependence on all relevant
complex phases is taken into account, and all the imaginary parts appearing in
the calculation are treated in a consistent way. The renormalization is
discussed in detail, and a hybrid on-shell/DRbar scheme is adopted. We also
derive the wave function normalization factors needed in processes with
external Higgs bosons and discuss effective couplings incorporating leading
higher-order effects. The complete one-loop corrections, supplemented by the
available two-loop corrections in the Feynman-diagrammatic approach for the
MSSM with real parameters and a resummation of the leading (s)bottom
corrections for complex parameters, are implemented into the public Fortran
code FeynHiggs2.5. In our numerical analysis the full results for the
Higgs-boson masses and couplings are compared with various approximations, and
CP-violating effects in the mixing of the heavy Higgs bosons are analyzed in
detail. We find sizable deviations in comparison with the approximations often
made in the literature.
| [
{
"created": "Mon, 27 Nov 2006 10:01:09 GMT",
"version": "v1"
},
{
"created": "Mon, 29 Jan 2007 09:43:20 GMT",
"version": "v2"
}
] | 2010-10-27 | [
[
"Frank",
"M.",
""
],
[
"Hahn",
"T.",
""
],
[
"Heinemeyer",
"S.",
""
],
[
"Hollik",
"W.",
""
],
[
"Rzehak",
"H.",
""
],
[
"Weiglein",
"G.",
""
]
] | New results for the complete one-loop contributions to the masses and mixing effects in the Higgs sector are obtained for the MSSM with complex parameters using the Feynman-diagrammatic approach. The full dependence on all relevant complex phases is taken into account, and all the imaginary parts appearing in the calculation are treated in a consistent way. The renormalization is discussed in detail, and a hybrid on-shell/DRbar scheme is adopted. We also derive the wave function normalization factors needed in processes with external Higgs bosons and discuss effective couplings incorporating leading higher-order effects. The complete one-loop corrections, supplemented by the available two-loop corrections in the Feynman-diagrammatic approach for the MSSM with real parameters and a resummation of the leading (s)bottom corrections for complex parameters, are implemented into the public Fortran code FeynHiggs2.5. In our numerical analysis the full results for the Higgs-boson masses and couplings are compared with various approximations, and CP-violating effects in the mixing of the heavy Higgs bosons are analyzed in detail. We find sizable deviations in comparison with the approximations often made in the literature. |
2307.05516 | Xue Jie Liu | Xuejie Liu and Yue Tan and Dianyong Chen and Hongxia Huang and Jialun
Ping | Investigation of the $N\bar{D}$ system in quark delocalization color
screening model | arXiv admin note: text overlap with arXiv:2211.09433 | null | null | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work we systematically calculate the pentaquark systems with quark
contents $qqqq\bar{c}$ with the analyzed total spin and parity quantum numbers
of $J^{P}=\frac{1}{2}^{-}$, $J^{P}=\frac{3}{2}^{-}$ and
$J^{P}=\frac{5}{2}^{-}$, in the I=0, I=1 and I=2 isospin channels. The
effective potentials between baryon and meson clusters are given, and the
possible bound states are also investigated. Also, the study of the scattering
process of the open channels is performed to look for possible resonance state.
Our estimations indicate that several possible bound states and narrow
baryon-meson resonances are found from corresponding the calculation processes.
| [
{
"created": "Fri, 7 Jul 2023 02:08:46 GMT",
"version": "v1"
}
] | 2023-07-13 | [
[
"Liu",
"Xuejie",
""
],
[
"Tan",
"Yue",
""
],
[
"Chen",
"Dianyong",
""
],
[
"Huang",
"Hongxia",
""
],
[
"Ping",
"Jialun",
""
]
] | In this work we systematically calculate the pentaquark systems with quark contents $qqqq\bar{c}$ with the analyzed total spin and parity quantum numbers of $J^{P}=\frac{1}{2}^{-}$, $J^{P}=\frac{3}{2}^{-}$ and $J^{P}=\frac{5}{2}^{-}$, in the I=0, I=1 and I=2 isospin channels. The effective potentials between baryon and meson clusters are given, and the possible bound states are also investigated. Also, the study of the scattering process of the open channels is performed to look for possible resonance state. Our estimations indicate that several possible bound states and narrow baryon-meson resonances are found from corresponding the calculation processes. |
1306.2045 | Pere Masjuan | H. Czy\.z, A. Denig, S. Eidelman, H. Hu, F. Jegerlehner, B. Kloss,
J.H. K\"uhn, A. Kupsc, E. A. Kuraev, P. Masjuan (ed.), S.E. M\"uller, R.G
Ping, C.F. Redmer, P. Roig, P. Sanchez-Puertas, O. Shekhovtsova, H.
Spiesberger, E. Tomasi-Gustafsson, T. Teubner, M. Vanderhaeghen, G. Venanzoni
(ed.), Y. Wang | Constraining the Hadronic Contributions to the Muon Anomalous Magnetic
Moment | 45 pages, 17 contributions. Editors: P. Masjuan and G. Venanzoni | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The mini-proceedings of the Workshop on "Constraining the hadronic
contributions to the muon anomalous magnetic moment" which included the "13th
meeting of the Radio MonteCarLow WG" and the "Satellite meeting R-Measurements
at BES-III" held in Trento from April 10th to 12th, 2013, are presented. This
collaboration meeting aims to bring together the experimental e+e- collider
communities from BaBar, Belle, BESIII, CMD2, KLOE, and SND, with theorists
working in the fields of meson transitions form factors, hadronic contributions
to (g-2)_\mu and effective fine structure constant, and development of Monte
Carlo generator and Radiative Corrections for precision e+e- and tau physics.
| [
{
"created": "Sun, 9 Jun 2013 17:47:54 GMT",
"version": "v1"
}
] | 2013-06-11 | [
[
"Czyż",
"H.",
"",
"ed."
],
[
"Denig",
"A.",
"",
"ed."
],
[
"Eidelman",
"S.",
"",
"ed."
],
[
"Hu",
"H.",
"",
"ed."
],
[
"Jegerlehner",
"F.",
"",
"ed."
],
[
"Kloss",
"B.",
"",
"ed."
],
[
"Kühn",
"J. H.",
"",
"ed."
],
[
"Kupsc",
"A.",
"",
"ed."
],
[
"Kuraev",
"E. A.",
"",
"ed."
],
[
"Masjuan",
"P.",
"",
"ed."
],
[
"Müller",
"S. E.",
"",
"ed."
],
[
"Ping",
"R. G",
"",
"ed."
],
[
"Redmer",
"C. F.",
"",
"ed."
],
[
"Roig",
"P.",
"",
"ed."
],
[
"Sanchez-Puertas",
"P.",
"",
"ed."
],
[
"Shekhovtsova",
"O.",
"",
"ed."
],
[
"Spiesberger",
"H.",
"",
"ed."
],
[
"Tomasi-Gustafsson",
"E.",
"",
"ed."
],
[
"Teubner",
"T.",
"",
"ed."
],
[
"Vanderhaeghen",
"M.",
"",
"ed."
],
[
"Venanzoni",
"G.",
"",
"ed."
],
[
"Wang",
"Y.",
""
]
] | The mini-proceedings of the Workshop on "Constraining the hadronic contributions to the muon anomalous magnetic moment" which included the "13th meeting of the Radio MonteCarLow WG" and the "Satellite meeting R-Measurements at BES-III" held in Trento from April 10th to 12th, 2013, are presented. This collaboration meeting aims to bring together the experimental e+e- collider communities from BaBar, Belle, BESIII, CMD2, KLOE, and SND, with theorists working in the fields of meson transitions form factors, hadronic contributions to (g-2)_\mu and effective fine structure constant, and development of Monte Carlo generator and Radiative Corrections for precision e+e- and tau physics. |
hep-ph/0102265 | Serguey Petcov | S. M. Bilenky, S. Pascoli, S. T. Petcov | Majorana Neutrinos, Neutrino Mass Spectrum, CP-Violation and
Neutrinoless Double Beta-Decay: I. The Three-Neutrino Mixing Case | 51 pages, LATEX; 33 pages of text, 28 eps-files; the text includes 6
tables and 28 figures; results and conclusions unchanged, a reference to the
KATRIN project and Comments concerning its physics potential added; version
to be published in Physical Review D | Phys.Rev.D64:053010,2001 | 10.1103/PhysRevD.64.053010 | SISSA 1/2001/EP, January 2001 | hep-ph | null | Assuming mixing of three massive Majorana neutrinos, we study the
implications of the neutrino oscillation solutions of the solar and atmospheric
neutrino problems and of the results of the CHOOZ experiment for the
predictions of the effective Majorana mass in neutrinoless double beta decay,
|< m >|. The general case of CP-nonconservation is investigated. The predicted
values of |< m >|, depend strongly on the type of the neutrino mass spectrum,
on the solution of the solar neutrino problem, as well as on the values of the
two Majorana CP-violating phases, present in the lepton mixing matrix. We find
that i) $|< m >| \lesssim 0.02 $eV for a hierarchical neutrino mass spectrum,
ii) $|< m >| \lesssim 0.09 $eV if the spectrum is of the inverted hierarchy
type, and iii) $|< m >| \leq m$ in the case of three quasi-degenerate
neutrinos, m > 0 being the common neutrino mass scale which is limited by the
bounds from the $^3$H $\beta-$decay experiments, $m < 2.5 $eV. The observation
of the $(\beta \beta)_{0\nu}-$decay with a rate corresponding to $|< m >|
\gtrsim 0.02 $eV can provide unique information on the neutrino mass spectrum
and on the CP-violation in the lepton sector, and if CP-invariance holds - on
the relative CP-parities of the massive Majorana neutrinos.
| [
{
"created": "Wed, 21 Feb 2001 15:42:22 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Apr 2001 14:40:09 GMT",
"version": "v2"
},
{
"created": "Tue, 22 May 2001 09:57:12 GMT",
"version": "v3"
}
] | 2014-11-17 | [
[
"Bilenky",
"S. M.",
""
],
[
"Pascoli",
"S.",
""
],
[
"Petcov",
"S. T.",
""
]
] | Assuming mixing of three massive Majorana neutrinos, we study the implications of the neutrino oscillation solutions of the solar and atmospheric neutrino problems and of the results of the CHOOZ experiment for the predictions of the effective Majorana mass in neutrinoless double beta decay, |< m >|. The general case of CP-nonconservation is investigated. The predicted values of |< m >|, depend strongly on the type of the neutrino mass spectrum, on the solution of the solar neutrino problem, as well as on the values of the two Majorana CP-violating phases, present in the lepton mixing matrix. We find that i) $|< m >| \lesssim 0.02 $eV for a hierarchical neutrino mass spectrum, ii) $|< m >| \lesssim 0.09 $eV if the spectrum is of the inverted hierarchy type, and iii) $|< m >| \leq m$ in the case of three quasi-degenerate neutrinos, m > 0 being the common neutrino mass scale which is limited by the bounds from the $^3$H $\beta-$decay experiments, $m < 2.5 $eV. The observation of the $(\beta \beta)_{0\nu}-$decay with a rate corresponding to $|< m >| \gtrsim 0.02 $eV can provide unique information on the neutrino mass spectrum and on the CP-violation in the lepton sector, and if CP-invariance holds - on the relative CP-parities of the massive Majorana neutrinos. |
2003.06623 | Qin-Tao Song | S. Kumano, Qin-Tao Song | Deuteron polarizations in the proton-deuteron Drell-Yan process for
finding the gluon transversity | 8 pages, 2 figures, published in Phys. Rev. D 101 (2020) 094013. Some
notations are changed | Phys. Rev. D 101, 094013 (2020) | 10.1103/PhysRevD.101.094013 | KEK-TH-2192, J-PARC-TH-0215 | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The gluon transversity distribution in the deuteron is defined by the matrix
element between linearly-polarized deuteron states, and it could be
investigated in proton-deuteron collisions in addition to lepton-deuteron
scattering. The linear polarization of photon is often used, whereas it is
rarely used for the spin-1 deuteron. Therefore, it is desirable to express
deuteron-reaction cross sections in term of conventional deuteron spin
polarizations for actual experimental measurements. In this work, we
investigate how proton-deuteron Drell-Yan cross sections are expressed by the
conventional polarizations for finding the gluon transversity distribution. In
particular, we show that the gluon transversity can be measured in the
proton-deuteron Drell-Yan process by taking the cross-section difference
between the deuteron spin polarizations along the two-transverse axes. Since
the gluon transversity does not exist for the spin-1/2 nucleons, a finite gluon
transversity of the deuteron could indicate an "exotic" mechanism beyond the
simple bound system of the nucleons in the deuteron. Therefore, the gluon
transversity is an interesting and appropriate observable to shed light on a
new hadronic mechanism in nuclei.
| [
{
"created": "Sat, 14 Mar 2020 13:07:02 GMT",
"version": "v1"
},
{
"created": "Fri, 15 May 2020 02:33:02 GMT",
"version": "v2"
}
] | 2020-05-20 | [
[
"Kumano",
"S.",
""
],
[
"Song",
"Qin-Tao",
""
]
] | The gluon transversity distribution in the deuteron is defined by the matrix element between linearly-polarized deuteron states, and it could be investigated in proton-deuteron collisions in addition to lepton-deuteron scattering. The linear polarization of photon is often used, whereas it is rarely used for the spin-1 deuteron. Therefore, it is desirable to express deuteron-reaction cross sections in term of conventional deuteron spin polarizations for actual experimental measurements. In this work, we investigate how proton-deuteron Drell-Yan cross sections are expressed by the conventional polarizations for finding the gluon transversity distribution. In particular, we show that the gluon transversity can be measured in the proton-deuteron Drell-Yan process by taking the cross-section difference between the deuteron spin polarizations along the two-transverse axes. Since the gluon transversity does not exist for the spin-1/2 nucleons, a finite gluon transversity of the deuteron could indicate an "exotic" mechanism beyond the simple bound system of the nucleons in the deuteron. Therefore, the gluon transversity is an interesting and appropriate observable to shed light on a new hadronic mechanism in nuclei. |
hep-ph/9912431 | Cheuk-Yin Wong | Cheuk-Yin Wong (ORNL), E. S. Swanson (UPittsburgh,JLab), and T.
Barnes(ORNL,UTenn,UBonn,IKPJulich) | Cross Sections for pi- and rho-induced Dissociation of J/psi and psi' | 13 pages, in LaTex | Phys.Rev.C62:045201,2000 | 10.1103/PhysRevC.62.045201 | null | hep-ph nucl-th | null | We evaluate the cross sections for the dissociation of $J/\psi$ and $\psi'$
by $\pi$ and $\rho$ at low collision energies, using the quark-interchange
model of Barnes and Swanson. The dissociation cross section for $J/\psi$ by
$\pi$ is found to be relatively small with a maximum of about 1 mb and a
kinetic energy threshold of 0.65 GeV. The pion-induced $\psi'$ dissociation
cross section is found to be much larger, with a maximum of about 5 mb and a
lower threshold. Dissociation cross sections for $J/\psi$ and $\psi'$ by $\rho$
mesons are also evaluated and are found to be large near threshold.
| [
{
"created": "Mon, 20 Dec 1999 20:01:06 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Mar 2000 15:41:26 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Wong",
"Cheuk-Yin",
"",
"ORNL"
],
[
"Swanson",
"E. S.",
"",
"UPittsburgh,JLab"
],
[
"Barnes",
"T.",
"",
"ORNL,UTenn,UBonn,IKPJulich"
]
] | We evaluate the cross sections for the dissociation of $J/\psi$ and $\psi'$ by $\pi$ and $\rho$ at low collision energies, using the quark-interchange model of Barnes and Swanson. The dissociation cross section for $J/\psi$ by $\pi$ is found to be relatively small with a maximum of about 1 mb and a kinetic energy threshold of 0.65 GeV. The pion-induced $\psi'$ dissociation cross section is found to be much larger, with a maximum of about 5 mb and a lower threshold. Dissociation cross sections for $J/\psi$ and $\psi'$ by $\rho$ mesons are also evaluated and are found to be large near threshold. |
2307.01086 | Ke-Pan Xie | Shao-Ping Li, Ke-Pan Xie | A collider test of nano-Hertz gravitational waves from pulsar timing
arrays | 6 pages + 2 figures + appendix + references | null | null | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | A cosmic first-order phase transition (FOPT) occurring at MeV-scale provides
an attractive explanation for the nano-Hertz gravitational wave (GW) background
indicated by the recent pulsar timing array data from the NANOGrav, CPTA, EPTA
and PPTA collaborations. We propose this explanation can be further tested at
the colliders if the hidden sector couples to the Standard Model sector via
Higgs portal. Through a careful analysis of the thermal history of the hidden
sector, we demonstrate that in order to successfully explain the observed GW
signal, the portal coupling must be sizable that it can be probed through Higgs
invisible decay at the LHC or future lepton colliders such as CEPC, ILC, and
FCC-ee. Our research offers a promising avenue to uncover the physical origin
of the nano-Hertz GWs through particle physics experiments.
| [
{
"created": "Mon, 3 Jul 2023 15:07:43 GMT",
"version": "v1"
},
{
"created": "Wed, 6 Sep 2023 01:24:06 GMT",
"version": "v2"
}
] | 2023-09-07 | [
[
"Li",
"Shao-Ping",
""
],
[
"Xie",
"Ke-Pan",
""
]
] | A cosmic first-order phase transition (FOPT) occurring at MeV-scale provides an attractive explanation for the nano-Hertz gravitational wave (GW) background indicated by the recent pulsar timing array data from the NANOGrav, CPTA, EPTA and PPTA collaborations. We propose this explanation can be further tested at the colliders if the hidden sector couples to the Standard Model sector via Higgs portal. Through a careful analysis of the thermal history of the hidden sector, we demonstrate that in order to successfully explain the observed GW signal, the portal coupling must be sizable that it can be probed through Higgs invisible decay at the LHC or future lepton colliders such as CEPC, ILC, and FCC-ee. Our research offers a promising avenue to uncover the physical origin of the nano-Hertz GWs through particle physics experiments. |
hep-ph/0107100 | Kaladi Babu | K.S. Babu (Oklahoma State University), B. Dutta (Texas A & M
University) and R.N. Mohapatra (University of Maryland) | Solving the Strong CP and the SUSY Phase Problems with Parity Symmetry | 16 pages RevTeX, 2 figures | Phys.Rev.D65:016005,2002 | 10.1103/PhysRevD.65.016005 | OSU-HEP-01-04, UMDPP-01-62, CTP-TAMU-20-01 | hep-ph | null | We propose a simultaneous solution to the strong CP problem and the SUSY
phase problem based on parity symmetry realized when the supersymmetric
standard model is embedded into a left-right symmetric framework at a scale
near 2 x 10^{16} GeV, as suggested by neutrino masses and gauge coupling
unification. In this class of models, owing to parity, SUSY contributions to
the muon anomalous magnetic moment can be naturally large without conflicting
with the EDM of the electron and the neutron. The strong CP violation parameter
\theta is zero at the tree level, also due to parity (P), but is induced due to
P-violating effects below the unification scale. We estimate the induced \theta
to be < 10^{-16}, if we adopt a constrained supersymmetric spectrum with
universal scalar masses. In the more general SUSY breaking scenario, after
imposing flavor changing constraints, we find theta ~ (10^{-8}-10^{-10}), which
is compatible with, but not much below the present limit on neutron EDM. We
also argue that potential non-perturbative corrections to \theta from quantum
gravitational effects are not excessive in these models.
| [
{
"created": "Mon, 9 Jul 2001 19:45:00 GMT",
"version": "v1"
}
] | 2014-11-17 | [
[
"Babu",
"K. S.",
"",
"Oklahoma State University"
],
[
"Dutta",
"B.",
"",
"Texas A & M\n University"
],
[
"Mohapatra",
"R. N.",
"",
"University of Maryland"
]
] | We propose a simultaneous solution to the strong CP problem and the SUSY phase problem based on parity symmetry realized when the supersymmetric standard model is embedded into a left-right symmetric framework at a scale near 2 x 10^{16} GeV, as suggested by neutrino masses and gauge coupling unification. In this class of models, owing to parity, SUSY contributions to the muon anomalous magnetic moment can be naturally large without conflicting with the EDM of the electron and the neutron. The strong CP violation parameter \theta is zero at the tree level, also due to parity (P), but is induced due to P-violating effects below the unification scale. We estimate the induced \theta to be < 10^{-16}, if we adopt a constrained supersymmetric spectrum with universal scalar masses. In the more general SUSY breaking scenario, after imposing flavor changing constraints, we find theta ~ (10^{-8}-10^{-10}), which is compatible with, but not much below the present limit on neutron EDM. We also argue that potential non-perturbative corrections to \theta from quantum gravitational effects are not excessive in these models. |
hep-ph/0412367 | Leonard Gamberg | Leonard P. Gamberg | Transversity of quarks and nucleons in SIDIS and Drell Yan | LaTeX2e, 4 pages, 4 ps figures, uses ws-procs9x6. Contribution to the
16th International Spin Physics Symposium, SPIN2004, October 10-16, 2004,
Trieste, Italy | null | 10.1142/9789812701909_0071 | null | hep-ph | null | We consider the leading and sub-leading twist $T$-odd and even contributions
to the $\cos 2\phi$ azimuthal asymmetry in unpolarized dilepton production in
Drell-Yan Scattering and semi-inclusive deep inelastic scattering of pions.
| [
{
"created": "Thu, 23 Dec 2004 18:33:34 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Dec 2004 04:30:42 GMT",
"version": "v2"
}
] | 2017-08-23 | [
[
"Gamberg",
"Leonard P.",
""
]
] | We consider the leading and sub-leading twist $T$-odd and even contributions to the $\cos 2\phi$ azimuthal asymmetry in unpolarized dilepton production in Drell-Yan Scattering and semi-inclusive deep inelastic scattering of pions. |
1003.4505 | Mads Toudal Frandsen | Mads T. Frandsen and Subir Sarkar (Oxford) | Asymmetric dark matter and the Sun | 4 pages, 3 figures (RevTex); Capture rate corrected to obey the
geometrical bound; Changes in adopted cross-sections and particle physics
motivation; Conclusions concerning helioseismology and solar neutrino fluxes
unchanged | Phys.Rev.Lett.105:011301,2010 | 10.1103/PhysRevLett.105.011301 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Cold dark matter particles with an intrinsic matter-antimatter asymmetry do
not annihilate after gravitational capture by the Sun and can affect its
interior structure. The rate of capture is exponentially enhanced when such
particles have self-interactions of the right order to explain structure
formation on galactic scales. A `dark baryon' of mass 5 GeV is a natural
candidate and has the required relic abundance if its asymmetry is similar to
that of ordinary baryons. We show that such particles can solve the `solar
composition problem'. The predicted small decrease in the low energy neutrino
fluxes may be measurable by the Borexino and SNO+ experiments.
| [
{
"created": "Tue, 23 Mar 2010 19:53:50 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Jun 2010 15:31:22 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Frandsen",
"Mads T.",
"",
"Oxford"
],
[
"Sarkar",
"Subir",
"",
"Oxford"
]
] | Cold dark matter particles with an intrinsic matter-antimatter asymmetry do not annihilate after gravitational capture by the Sun and can affect its interior structure. The rate of capture is exponentially enhanced when such particles have self-interactions of the right order to explain structure formation on galactic scales. A `dark baryon' of mass 5 GeV is a natural candidate and has the required relic abundance if its asymmetry is similar to that of ordinary baryons. We show that such particles can solve the `solar composition problem'. The predicted small decrease in the low energy neutrino fluxes may be measurable by the Borexino and SNO+ experiments. |
1606.01058 | Antoni Szczurek | Mariola Klusek-Gawenda, Wolfgang Schaefer and Antoni Szczurek | Two-gluon exchange contribution to elastic $\gamma \gamma \to \gamma
\gamma$ scattering and production of two-photons in ultraperipheral
ultrarelativistic heavy ion and proton-proton collisions | 15 pages, 16 figures, 1 table, a reference was added | null | 10.1016/j.physletb.2016.08.059 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the two-gluon exchange contribution (formally three-loops) to
elastic photon-photon scattering in the high-energy approximation. The elastic
$\gamma\gamma \to \gamma \gamma$ amplitude is given in the impact-factor
representation for all helicity configurations and finite quark masses. We
discuss the importance of including the charm quark, which contribution, due to
interference, can enhance the cross section considerably. We investigate the
contribution to the $\gamma \gamma \to \gamma \gamma$ amplitude from the soft
region, by studying its dependence on nonperturbative gluon mass. Helicity-flip
contributions are shown to be much smaller than helicity-conserving ones. We
identify region(s) of phase space where the two-gluon exchange contribution
becomes important ingredient compared to box and nonperturbative VDM-Regge
mechanisms considered in the literature. Consequences for the $A A \to A A
\gamma \gamma$ reaction are discussed. Several differential distributions are
shown. A feasibility study to observe the effect of two-gluon exchange is
presented. We perform a similar analysis for the $p p \to p p \gamma \gamma$
reaction. Only by imposing severe cuts on $M_{\gamma \gamma}$ and a narrow
window on photon transverse momenta the two gluon contribution becomes
comparable to the box contribution but the corresponding cross section is
rather small.
| [
{
"created": "Fri, 3 Jun 2016 12:24:03 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Jun 2016 11:17:39 GMT",
"version": "v2"
}
] | 2016-09-07 | [
[
"Klusek-Gawenda",
"Mariola",
""
],
[
"Schaefer",
"Wolfgang",
""
],
[
"Szczurek",
"Antoni",
""
]
] | We discuss the two-gluon exchange contribution (formally three-loops) to elastic photon-photon scattering in the high-energy approximation. The elastic $\gamma\gamma \to \gamma \gamma$ amplitude is given in the impact-factor representation for all helicity configurations and finite quark masses. We discuss the importance of including the charm quark, which contribution, due to interference, can enhance the cross section considerably. We investigate the contribution to the $\gamma \gamma \to \gamma \gamma$ amplitude from the soft region, by studying its dependence on nonperturbative gluon mass. Helicity-flip contributions are shown to be much smaller than helicity-conserving ones. We identify region(s) of phase space where the two-gluon exchange contribution becomes important ingredient compared to box and nonperturbative VDM-Regge mechanisms considered in the literature. Consequences for the $A A \to A A \gamma \gamma$ reaction are discussed. Several differential distributions are shown. A feasibility study to observe the effect of two-gluon exchange is presented. We perform a similar analysis for the $p p \to p p \gamma \gamma$ reaction. Only by imposing severe cuts on $M_{\gamma \gamma}$ and a narrow window on photon transverse momenta the two gluon contribution becomes comparable to the box contribution but the corresponding cross section is rather small. |
2110.12830 | Natasa Vukasinovic | T. Agatonovi\'c-Jovin, N. Vuka\v{s}inovi\'c, I.
Bo\v{z}ovi\'c-Jelisav\v{c}i\'c, G. Ka\v{c}arevi\'c, M. Radulovi\'c, J.
Stevanovi\'c, G. Milutinovi\'c-Dumbelovi\'c, I. Smiljani\'c | CP violation in the Higgs sector at ILC | Poster presented at the European Physical Society conference on high
energy physics (EPS-HEP2021), Online conference, July 26-30, 2021 | null | null | ILD-PHYS-PROC-2021-011 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | CP violation is one of Sakharov's conditions for the matter-antimatter
asymmetry of the Universe. The experimentally observed size of CP violation is
insufficient to account for this. Is CP violated in the Higgs sector? Could the
SM-like Higgs boson be a mixture of CP even and CP odd states of an extended
Higgs sector? With what precision could such effects be measured at future
electron-positron colliders? These questions will be discussed in the light of
the latest studies at ILC.
| [
{
"created": "Mon, 25 Oct 2021 11:51:23 GMT",
"version": "v1"
}
] | 2021-10-26 | [
[
"Agatonović-Jovin",
"T.",
""
],
[
"Vukašinović",
"N.",
""
],
[
"Božović-Jelisavčić",
"I.",
""
],
[
"Kačarević",
"G.",
""
],
[
"Radulović",
"M.",
""
],
[
"Stevanović",
"J.",
""
],
[
"Milutinović-Dumbelović",
"G.",
""
],
[
"Smiljanić",
"I.",
""
]
] | CP violation is one of Sakharov's conditions for the matter-antimatter asymmetry of the Universe. The experimentally observed size of CP violation is insufficient to account for this. Is CP violated in the Higgs sector? Could the SM-like Higgs boson be a mixture of CP even and CP odd states of an extended Higgs sector? With what precision could such effects be measured at future electron-positron colliders? These questions will be discussed in the light of the latest studies at ILC. |
1707.03534 | Ren-You Zhang | Wang Yong, Zhang Ren-You, Ma Wen-Gan, Li Xiao-Zhou, Wang Shao-Ming and
Bi Huan-Yu | $ZZ\gamma$ production in the NLO QCD+EW accuracy at the LHC | 25 pages, 10 figures | J. Phys. G: Nucl. Part. Phys. 44 (2017) 085002 | 10.1088/1361-6471/aa7787 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we present the first study of the impact of the
$\mathcal{O}(\alpha)$ EW correction to the $pp \to ZZ \gamma+X$ process at the
CERN Large Hadron Collider (LHC). The subsequent $Z$-boson leptonic decays are
considered at the leading order using the MadSpin method, which takes into
account the spin-correlation and off-shell effects from the $Z$-boson decays.
We provide numerical results of the integrated cross section and the kinematic
distributions for this process. In coping with final-state photon-jet
separation in the QCD real emission and photon-induced processes, we adopt both
the Frixione isolated-photon plus jets algorithm and the phenomenological
quark-to-photon fragmentation function method for comparison. We find that the
next-to-leading order (NLO) EW correction to the $ZZ\gamma$ production can be
sizeable and amounts to about $-7\%$ of the integrated cross section, and
provides a non$-$negligible contribution to the kinematic distributions,
particularly in the high energy region. We conclude that the NLO EW correction
should be included in precision theoretical predictions in order to match
future experimental accuracy.
| [
{
"created": "Wed, 12 Jul 2017 04:11:49 GMT",
"version": "v1"
}
] | 2017-08-02 | [
[
"Yong",
"Wang",
""
],
[
"Ren-You",
"Zhang",
""
],
[
"Wen-Gan",
"Ma",
""
],
[
"Xiao-Zhou",
"Li",
""
],
[
"Shao-Ming",
"Wang",
""
],
[
"Huan-Yu",
"Bi",
""
]
] | In this paper we present the first study of the impact of the $\mathcal{O}(\alpha)$ EW correction to the $pp \to ZZ \gamma+X$ process at the CERN Large Hadron Collider (LHC). The subsequent $Z$-boson leptonic decays are considered at the leading order using the MadSpin method, which takes into account the spin-correlation and off-shell effects from the $Z$-boson decays. We provide numerical results of the integrated cross section and the kinematic distributions for this process. In coping with final-state photon-jet separation in the QCD real emission and photon-induced processes, we adopt both the Frixione isolated-photon plus jets algorithm and the phenomenological quark-to-photon fragmentation function method for comparison. We find that the next-to-leading order (NLO) EW correction to the $ZZ\gamma$ production can be sizeable and amounts to about $-7\%$ of the integrated cross section, and provides a non$-$negligible contribution to the kinematic distributions, particularly in the high energy region. We conclude that the NLO EW correction should be included in precision theoretical predictions in order to match future experimental accuracy. |
2405.12691 | Azhothkaran Bhaghyesh Dr. | Nayana T S and Bhaghyesh | Spectra and Decay Properties of Higher Lying $B_C$ Meson States | 13 pages, 7 images | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, the spectra and decay properties of $B_c$ mesons ($c\bar{b}$)
have been investigated using a non-relativistic potential model incorporating
corrections from LQCD. The non-relativistic Schrodinger wave equation is solved
numerically using the Matrix Numerov Method. Using the obtained masses and wave
functions, decay widths, lifetime, branching ratios and radiative decay widths
are computed for the $c\bar{b}$ system. We compare the obtained results with
the experimental data and with other theoretical models.
| [
{
"created": "Tue, 21 May 2024 11:25:42 GMT",
"version": "v1"
}
] | 2024-05-22 | [
[
"S",
"Nayana T",
""
],
[
"Bhaghyesh",
"",
""
]
] | In this work, the spectra and decay properties of $B_c$ mesons ($c\bar{b}$) have been investigated using a non-relativistic potential model incorporating corrections from LQCD. The non-relativistic Schrodinger wave equation is solved numerically using the Matrix Numerov Method. Using the obtained masses and wave functions, decay widths, lifetime, branching ratios and radiative decay widths are computed for the $c\bar{b}$ system. We compare the obtained results with the experimental data and with other theoretical models. |
0809.4598 | Dumitru Ghilencea | I. Antoniadis, E. Dudas, D. M. Ghilencea, P. Tziveloglou | Higher Dimensional Operators in the MSSM | Contribution to the proceedings of the "Susy 2008" conference; (6
pages) | AIP Conf.Proc.1078:175-180,2009 | 10.1063/1.3051901 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The origin and the implications of higher dimensional effective operators in
4-dimensional theories are discussed in non-supersymmetric and supersymmetric
cases. Particular attention is paid to the role of general,
derivative-dependent field redefinitions which one can employ to obtain a
simpler form of the effective Lagrangian. An application is provided for the
Minimal Supersymmetric Standard Model extended with dimension-five R-parity
conserving operators, to identify the minimal irreducible set of such operators
after supersymmetry breaking. Among the physical consequences of this set of
operators are the presence of corrections to the MSSM Higgs sector and the
generation of "wrong"-Higgs Yukawa couplings and fermion-fermion-scalar-scalar
interactions. These couplings have implications for supersymmetry searches at
the LHC.
| [
{
"created": "Fri, 26 Sep 2008 11:19:42 GMT",
"version": "v1"
}
] | 2010-04-21 | [
[
"Antoniadis",
"I.",
""
],
[
"Dudas",
"E.",
""
],
[
"Ghilencea",
"D. M.",
""
],
[
"Tziveloglou",
"P.",
""
]
] | The origin and the implications of higher dimensional effective operators in 4-dimensional theories are discussed in non-supersymmetric and supersymmetric cases. Particular attention is paid to the role of general, derivative-dependent field redefinitions which one can employ to obtain a simpler form of the effective Lagrangian. An application is provided for the Minimal Supersymmetric Standard Model extended with dimension-five R-parity conserving operators, to identify the minimal irreducible set of such operators after supersymmetry breaking. Among the physical consequences of this set of operators are the presence of corrections to the MSSM Higgs sector and the generation of "wrong"-Higgs Yukawa couplings and fermion-fermion-scalar-scalar interactions. These couplings have implications for supersymmetry searches at the LHC. |
1406.4630 | Toru Kojo | Toru Kojo | Chiral Spirals from Noncontinuous Chiral Symmetry: The Gross-Neveu model
results | 31 pages, 5 figures; v2 published in PRD | Phys. Rev. D 90, 065030 (2014) | 10.1103/PhysRevD.90.065030 | null | hep-ph hep-lat hep-th nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It is shown that the inhomogeneous chiral condensate in the Gross-Neveu (GN)
model takes the chiral spiral form, even though the thermodynamic functional
depends only on the chiral scalar density. It is the inhomogeneity of the
chiral scalar condensate that drives the spatial modulations of the
pseudoscalar one. The result has broader implications once we start to think of
fundamental theories behind the effective models. In particular, some effective
interactions---which may be omitted for descriptions of the homogeneous
phases---can be dynamically enhanced due to the spatial modulations of the
large mean fields. Implications for the four-dimensional counterparts of the GN
model are discussed. In a quark matter context, proper forms of the effective
models for the inhomogeneous phases are speculated, through considerations on
the Fermi-Dirac sea coupling.
| [
{
"created": "Wed, 18 Jun 2014 08:19:08 GMT",
"version": "v1"
},
{
"created": "Wed, 17 Sep 2014 18:15:17 GMT",
"version": "v2"
}
] | 2014-10-01 | [
[
"Kojo",
"Toru",
""
]
] | It is shown that the inhomogeneous chiral condensate in the Gross-Neveu (GN) model takes the chiral spiral form, even though the thermodynamic functional depends only on the chiral scalar density. It is the inhomogeneity of the chiral scalar condensate that drives the spatial modulations of the pseudoscalar one. The result has broader implications once we start to think of fundamental theories behind the effective models. In particular, some effective interactions---which may be omitted for descriptions of the homogeneous phases---can be dynamically enhanced due to the spatial modulations of the large mean fields. Implications for the four-dimensional counterparts of the GN model are discussed. In a quark matter context, proper forms of the effective models for the inhomogeneous phases are speculated, through considerations on the Fermi-Dirac sea coupling. |
hep-ph/9910357 | Janusz Gluza | M. Czakon, J. Gluza, M. Zralek | Are Neutrinos Dirac or Majorana Particles? | 18 pages, minor typos corrected (e.g. in Eq.(55)) | Acta Phys.Polon.B30:3121-3138,1999 | null | null | hep-ph | null | In spite of the general belief that neutrinos are Majorana particles, their
character should be revealed experimentally. We begin by discussing why it is
so difficult in terrestrial experiments. If neutrinos are Majorana particles,
the first signal should come from neutrinoless double $\beta $ decay. Still the
search for such a decay of various nuclei is negative. We outline how the
present knowledge of neutrino masses and mixing matrix elements combined with
the bound from $(\beta \beta)_{0\nu}$ decay could help to determine their
nature.
| [
{
"created": "Fri, 15 Oct 1999 16:06:47 GMT",
"version": "v1"
},
{
"created": "Sat, 16 Oct 1999 10:36:02 GMT",
"version": "v2"
},
{
"created": "Thu, 28 Oct 1999 09:41:52 GMT",
"version": "v3"
}
] | 2011-04-15 | [
[
"Czakon",
"M.",
""
],
[
"Gluza",
"J.",
""
],
[
"Zralek",
"M.",
""
]
] | In spite of the general belief that neutrinos are Majorana particles, their character should be revealed experimentally. We begin by discussing why it is so difficult in terrestrial experiments. If neutrinos are Majorana particles, the first signal should come from neutrinoless double $\beta $ decay. Still the search for such a decay of various nuclei is negative. We outline how the present knowledge of neutrino masses and mixing matrix elements combined with the bound from $(\beta \beta)_{0\nu}$ decay could help to determine their nature. |
hep-ph/0003226 | Ed Stoeffhaas | M. M. Block, F. Halzen, G. Pancheri, and T. Stanev | Breaking the Barriers - Uniting Accelerator and Cosmic Ray p-p Cross
Sections | 16 pages, Latex2e, uses epsfig.sty, 19 postscript figures. Presented
by M. M. Block at the 25th Pamir-Chacaltaya Collaboration Workshop, Lodz,
Poland, Nov. 3-7, 1999 | null | null | NUHEP-708 | hep-ph | null | We make a QCD-inspired parameterization of all accelerator data on forward
proton-proton and antiproton-proton scattering amplitudes. Using vector
dominance and the additive quark model, we show that the same parameters also
fit gamma p and gamma gamma interactions. Using the high energy predictions of
our model, along with Glauber theory, we calculate proton-air cross sections at
energies near sqrt s approx 30 TeV. The comparisons of p-air cosmic ray
measurements with our QCD model predictions provide a strong constraint on the
inclusive particle production cross section.
| [
{
"created": "Wed, 22 Mar 2000 21:05:57 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Block",
"M. M.",
""
],
[
"Halzen",
"F.",
""
],
[
"Pancheri",
"G.",
""
],
[
"Stanev",
"T.",
""
]
] | We make a QCD-inspired parameterization of all accelerator data on forward proton-proton and antiproton-proton scattering amplitudes. Using vector dominance and the additive quark model, we show that the same parameters also fit gamma p and gamma gamma interactions. Using the high energy predictions of our model, along with Glauber theory, we calculate proton-air cross sections at energies near sqrt s approx 30 TeV. The comparisons of p-air cosmic ray measurements with our QCD model predictions provide a strong constraint on the inclusive particle production cross section. |
1009.5707 | C\'edric Lorc\'e | C\'edric Lorc\'e and Barbara Pasquini | Generalized Transverse-Momentum Dependent Parton Distributions in
Light-Cone Quark Models | Proceedings for the "Light Cone 2010 Relativistic Hadronic and
Particle Physics" workshop, 3 Figs, 8pp | PoS LC2010:057,2010 | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss the general formalism for the calculation in light-cone quark
models of the fully unintegrated, off-diagonal quark-quark correlator of the
nucleon. The corresponding distributions in impact parameter space are the
Wigner or phase-space distributions. The results obtained in two different
light-cone quark models in the case of unpolarized quarks in an unpolarized
proton are very similar and present a non-trivial shape which can be understood
as due to the orbital motion of the quarks.
| [
{
"created": "Tue, 28 Sep 2010 21:50:07 GMT",
"version": "v1"
}
] | 2011-03-10 | [
[
"Lorcé",
"Cédric",
""
],
[
"Pasquini",
"Barbara",
""
]
] | We discuss the general formalism for the calculation in light-cone quark models of the fully unintegrated, off-diagonal quark-quark correlator of the nucleon. The corresponding distributions in impact parameter space are the Wigner or phase-space distributions. The results obtained in two different light-cone quark models in the case of unpolarized quarks in an unpolarized proton are very similar and present a non-trivial shape which can be understood as due to the orbital motion of the quarks. |
1004.4452 | Andrej El | Andrej El, Zhe Xu, Carsten Greiner | Third-order dissipative hydrodynamics from the entropy principle | 5 pages 2 figures. To appear in the proceedings of the 26th Winter
Workshop on Nuclear Dynamics (2010) | J.Phys.Conf.Ser.230:012046,2010 | 10.1088/1742-6596/230/1/012046 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review the entropy based derivation of third-order hydrodynamic equations
and compare their solutions in one-dimensional boost-invariant geometry with
calculations by the partonic cascade BAMPS. We demonstrate that Grad's
approximation, which underlies the derivation of both Israel-Stewart and
third-order equations, describes the transverse spectra from BAMPS with high
accuracy. At the same time solutions of third-order equations are much closer
to BAMPS results than solutions of Israel-Stewart equations. Introducing a
resummation scheme for all higher-oder corrections to one-dimensional
hydrodynamic equation we demonstrate the importance of higher-order terms if
the Knudsen number is large.
| [
{
"created": "Mon, 26 Apr 2010 09:42:42 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"El",
"Andrej",
""
],
[
"Xu",
"Zhe",
""
],
[
"Greiner",
"Carsten",
""
]
] | We review the entropy based derivation of third-order hydrodynamic equations and compare their solutions in one-dimensional boost-invariant geometry with calculations by the partonic cascade BAMPS. We demonstrate that Grad's approximation, which underlies the derivation of both Israel-Stewart and third-order equations, describes the transverse spectra from BAMPS with high accuracy. At the same time solutions of third-order equations are much closer to BAMPS results than solutions of Israel-Stewart equations. Introducing a resummation scheme for all higher-oder corrections to one-dimensional hydrodynamic equation we demonstrate the importance of higher-order terms if the Knudsen number is large. |
1110.0004 | Christopher Lee | Andrew Hornig, Christopher Lee, Jonathan R. Walsh, and Saba Zuberi | Double Non-Global Logarithms In-N-Out of Jets | 19 pages, 10 figures. v2: minor edits, additional discussion in
Introduction. v3: version published in JHEP | JHEP 1201:149,2012 | 10.1007/JHEP01(2012)149 | MIT-CTP 4302, INT-PUB-11-043 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We derive the leading non-global logarithms (NGLs) of ratios of jet masses
m_{1,2} and a jet energy veto \Lambda due to soft gluons splitting into regions
in and out of jets. Such NGLs appear in any exclusive jet cross section with
multiple jet measurements or with a veto imposed on additional jets. Here, we
consider back-to-back jets of radius R produced in e^+e^- collisions, found
with a cone or recombination algorithm. The leading NGLs are of the form
\alpha_s^2 \ln^2(\Lambda/m_{1,2}) or \alpha_s^2\ln^2(m_1/m_2). Their
coefficients depend both on the algorithm and on R. We consider cone, \kt,
anti-\kt, and Cambridge-Aachen algorithms. In addition to determining the full
algorithmic and R dependence of the leading NGLs, we derive new relations among
their coefficients. We also derive to all orders in \alpha_s a factorized form
for the soft function S(k_L,k_R,\Lambda) in the cross section
\sigma(m_1,m_2,\Lambda) in which dependence on each of the global logs of
\mu/k_L, \mu/k_R and \mu/\Lambda determined by the renormalization group are
separated from one another and from the non-global logs. The same kind of soft
function, its associated non-global structure, and the algorithmic dependence
we derive here will also arise in exclusive jet cross sections at hadron
colliders, and must be understood and brought under control to achieve precise
theoretical predictions.
| [
{
"created": "Fri, 30 Sep 2011 20:00:06 GMT",
"version": "v1"
},
{
"created": "Fri, 28 Oct 2011 18:56:55 GMT",
"version": "v2"
},
{
"created": "Sat, 7 Apr 2012 04:42:07 GMT",
"version": "v3"
}
] | 2015-05-30 | [
[
"Hornig",
"Andrew",
""
],
[
"Lee",
"Christopher",
""
],
[
"Walsh",
"Jonathan R.",
""
],
[
"Zuberi",
"Saba",
""
]
] | We derive the leading non-global logarithms (NGLs) of ratios of jet masses m_{1,2} and a jet energy veto \Lambda due to soft gluons splitting into regions in and out of jets. Such NGLs appear in any exclusive jet cross section with multiple jet measurements or with a veto imposed on additional jets. Here, we consider back-to-back jets of radius R produced in e^+e^- collisions, found with a cone or recombination algorithm. The leading NGLs are of the form \alpha_s^2 \ln^2(\Lambda/m_{1,2}) or \alpha_s^2\ln^2(m_1/m_2). Their coefficients depend both on the algorithm and on R. We consider cone, \kt, anti-\kt, and Cambridge-Aachen algorithms. In addition to determining the full algorithmic and R dependence of the leading NGLs, we derive new relations among their coefficients. We also derive to all orders in \alpha_s a factorized form for the soft function S(k_L,k_R,\Lambda) in the cross section \sigma(m_1,m_2,\Lambda) in which dependence on each of the global logs of \mu/k_L, \mu/k_R and \mu/\Lambda determined by the renormalization group are separated from one another and from the non-global logs. The same kind of soft function, its associated non-global structure, and the algorithmic dependence we derive here will also arise in exclusive jet cross sections at hadron colliders, and must be understood and brought under control to achieve precise theoretical predictions. |
1203.4059 | Kohei Kamada | Kohei Kamada, Tsutomu Kobayashi, Tomo Takahashi, Masahide Yamaguchi,
Jun'ichi Yokoyama | Generalized Higgs inflation | 9 pages; v2, references added; v3, published version | null | 10.1103/PhysRevD.86.023504 | DESY 12-043; RESCEU-4/12 | hep-ph astro-ph.CO gr-qc | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study Higgs inflation in the context of generalized G-inflation, i.e. the
most general single-field inflation model with second-order field equations.
The four variants of Higgs inflation proposed so far in the literature can be
accommodated at one time in our framework. We also propose yet another class of
Higgs inflation, the running Einstein inflation model, that can naturally arise
from the generalized G-inflation framework. As a result, five Higgs inflation
models in all should be discussed on an equal footing. Concise formulas for
primordial fluctuations in these generalized Higgs inflation models are
provided, which will be helpful to determine which model is favored from the
future experiments and observations such as the Large Hadron Collider and the
Planck satellite.
| [
{
"created": "Mon, 19 Mar 2012 09:13:00 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Apr 2012 01:57:40 GMT",
"version": "v2"
},
{
"created": "Thu, 12 Jul 2012 15:46:16 GMT",
"version": "v3"
}
] | 2013-05-30 | [
[
"Kamada",
"Kohei",
""
],
[
"Kobayashi",
"Tsutomu",
""
],
[
"Takahashi",
"Tomo",
""
],
[
"Yamaguchi",
"Masahide",
""
],
[
"Yokoyama",
"Jun'ichi",
""
]
] | We study Higgs inflation in the context of generalized G-inflation, i.e. the most general single-field inflation model with second-order field equations. The four variants of Higgs inflation proposed so far in the literature can be accommodated at one time in our framework. We also propose yet another class of Higgs inflation, the running Einstein inflation model, that can naturally arise from the generalized G-inflation framework. As a result, five Higgs inflation models in all should be discussed on an equal footing. Concise formulas for primordial fluctuations in these generalized Higgs inflation models are provided, which will be helpful to determine which model is favored from the future experiments and observations such as the Large Hadron Collider and the Planck satellite. |
hep-ph/0306242 | Francesco Vissani | Charanjit S. Aulakh, Borut Bajc, Alejandra Melfo, Goran Senjanovic,
Francesco Vissani | The minimal supersymmetric grand unified theory | 4 pages | Phys.Lett.B588:196-202,2004 | 10.1016/j.physletb.2004.03.031 | null | hep-ph | null | We show that the minimal renormalizable supersymmetric SO(10) GUT with the
usual three generations of spinors has a Higgs sector consisting only of a
"light" 10-dimensional and "heavy" 126, 126-bar and 210 supermultiplets. The
theory has only two sets of Yukawa couplings with fifteen real parameters and
ten real parameters in the Higgs superpotential. It accounts correctly for all
the fermion masses and mixings. The theory predicts at low energies the MSSM
with exact R-parity. It is arguably the minimal consistent supersymmetric grand
unified theory.
| [
{
"created": "Tue, 24 Jun 2003 18:04:47 GMT",
"version": "v1"
}
] | 2011-02-09 | [
[
"Aulakh",
"Charanjit S.",
""
],
[
"Bajc",
"Borut",
""
],
[
"Melfo",
"Alejandra",
""
],
[
"Senjanovic",
"Goran",
""
],
[
"Vissani",
"Francesco",
""
]
] | We show that the minimal renormalizable supersymmetric SO(10) GUT with the usual three generations of spinors has a Higgs sector consisting only of a "light" 10-dimensional and "heavy" 126, 126-bar and 210 supermultiplets. The theory has only two sets of Yukawa couplings with fifteen real parameters and ten real parameters in the Higgs superpotential. It accounts correctly for all the fermion masses and mixings. The theory predicts at low energies the MSSM with exact R-parity. It is arguably the minimal consistent supersymmetric grand unified theory. |
hep-ph/0507167 | Dremin | I.M. Dremin | Ring-like events: Cherenkov gluons or Mach waves? | 12 pages, 5 figures, LATEX, misprint corrected | Nucl.Phys.A767:233-247,2006 | 10.1016/j.nuclphysa.2005.12.015 | null | hep-ph | null | Similar to electromagnetic forces, strong interactions might induce such
collective effects as Cherenkov and Mach waves. Their conical structure would
be responsible for specific ring-like events. The theoretical and experimental
arguments in favor of these phenomena are discussed and their most important
features are described.
| [
{
"created": "Thu, 14 Jul 2005 09:29:37 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Jul 2005 10:03:13 GMT",
"version": "v2"
},
{
"created": "Tue, 2 Aug 2005 08:43:31 GMT",
"version": "v3"
},
{
"created": "Mon, 22 Aug 2005 09:05:27 GMT",
"version": "v4"
},
{
"created": "Tue, 6 Sep 2005 08:51:18 GMT",
"version": "v5"
}
] | 2008-11-26 | [
[
"Dremin",
"I. M.",
""
]
] | Similar to electromagnetic forces, strong interactions might induce such collective effects as Cherenkov and Mach waves. Their conical structure would be responsible for specific ring-like events. The theoretical and experimental arguments in favor of these phenomena are discussed and their most important features are described. |
2312.15442 | Jiang Yan | Jiang Yan, Xing-Gang Wu, Zhi-Fei Wu, Jing-Hao Shan, Hua Zhou | Reanalysis of the top-quark pair production via the $e^+ e^-$
annihilation near the threshold region up to N$^3$LO QCD corrections | 10 pages, 6 figures | null | 10.1016/j.physletb.2024.138664 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | In this paper, we present an improved analysis of the top-quark pair
production via the process $e^{+}e^{-}\to \gamma^{*}\to t\bar{t}$ near the
threshold region up to next-to-next-to-next-to-leading order (N$^3$LO) QCD
corrections. Near the threshold region, the top-quark velocity $v$ tends to
zero, leading to Coulomb singularity. To achieve a reasonable prediction in the
threshold region, we reconstruct the analytical expression for the
Coulomb-terms up to N$^{3}$LO accuracy by using the PSLQ algorithm, whose
numerical values agree well with the previous N$^3$LO-level calculations. It is
found that the N$^{3}$LO series still has sizable renormalization scale
dependence, and to improve the precision of the series, we apply the Principle
of Maximum Conformality to eliminate such scale dependence. After that, the
Coulomb part is resummed into a Sommerfeld-Gamow-Sakharov factor, which finally
leads to a much more reasonable behavior near the threshold region.
| [
{
"created": "Sun, 24 Dec 2023 09:26:04 GMT",
"version": "v1"
},
{
"created": "Tue, 30 Jan 2024 04:07:41 GMT",
"version": "v2"
},
{
"created": "Wed, 17 Apr 2024 07:34:57 GMT",
"version": "v3"
}
] | 2024-04-25 | [
[
"Yan",
"Jiang",
""
],
[
"Wu",
"Xing-Gang",
""
],
[
"Wu",
"Zhi-Fei",
""
],
[
"Shan",
"Jing-Hao",
""
],
[
"Zhou",
"Hua",
""
]
] | In this paper, we present an improved analysis of the top-quark pair production via the process $e^{+}e^{-}\to \gamma^{*}\to t\bar{t}$ near the threshold region up to next-to-next-to-next-to-leading order (N$^3$LO) QCD corrections. Near the threshold region, the top-quark velocity $v$ tends to zero, leading to Coulomb singularity. To achieve a reasonable prediction in the threshold region, we reconstruct the analytical expression for the Coulomb-terms up to N$^{3}$LO accuracy by using the PSLQ algorithm, whose numerical values agree well with the previous N$^3$LO-level calculations. It is found that the N$^{3}$LO series still has sizable renormalization scale dependence, and to improve the precision of the series, we apply the Principle of Maximum Conformality to eliminate such scale dependence. After that, the Coulomb part is resummed into a Sommerfeld-Gamow-Sakharov factor, which finally leads to a much more reasonable behavior near the threshold region. |
hep-ph/9805454 | Choi Myoung-Taek | Myoung-Taek Choi and Jae Kwan Kim (Korea Advanced Institute of Science
and Technology, Korea) | Determination of $|V_{cb}|$ from the polarization of vector meson in the
semileptonic decay of $B$ and $B_c$ meson | 11 pages, RevTeX | Phys.Lett.B419:377-380,1998 | 10.1016/S0370-2693(97)01480-9 | null | hep-ph | null | Since the degree of polarization of the vector particle in semileptonic decay
strongly influences the decay width of the particles, it can be used as a
measure of CKM matrix elements. We show that |V_{cb}| can be determined from
the measurement of polarization of vector meson in B,B_c --> V l nu decay,
where $V$ is vector meson.
| [
{
"created": "Tue, 26 May 1998 05:38:55 GMT",
"version": "v1"
}
] | 2010-11-23 | [
[
"Choi",
"Myoung-Taek",
"",
"Korea Advanced Institute of Science\n and Technology, Korea"
],
[
"Kim",
"Jae Kwan",
"",
"Korea Advanced Institute of Science\n and Technology, Korea"
]
] | Since the degree of polarization of the vector particle in semileptonic decay strongly influences the decay width of the particles, it can be used as a measure of CKM matrix elements. We show that |V_{cb}| can be determined from the measurement of polarization of vector meson in B,B_c --> V l nu decay, where $V$ is vector meson. |
1410.1070 | Mikhail Krivoruchenko | M. I. Krivoruchenko | $\pi_{e3}$ form factor $f_{-}$ near the mass shell | 14 pages latex, 1 figure, 1 table, new references added, minor style
changes, accepted for publication in Advances in High Energy Physics | Advances in High Energy Physics, Volume 2015 (2015), Article ID
656239, 9 pages | 10.1155/2015/656239 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The generalized Ward-Takahashi identity (gWTI) in the pion sector for broken
isotopic symmetry is derived and used for the model-independent calculation of
the longitudinal form factor $f_{-}$ of the $\pi_{e3}$ vector vertex. The
on-shell $f_{-}$ is found to be proportional to the mass difference of the
pions and the difference between the vector isospin $T = 1$ and scalar isospin
$ T = 2 $ pion radii. A numerical estimate of the form factor yields a value
two times higher than the previous estimate from the quark model. Off-shell
form factors are known to be ambiguous because of the gauge dependence and the
freedom in the parameterization of the fields. The near-mass-shell $f_{-}$
appears to be an exception, allowing for experimental verification of the
consequences of the gWTI. We calculate the near-mass-shell $f_{-}$ using the
gWTI and dispersion techniques. The results are discussed in the context of the
conservation of vector current (CVC) hypothesis.
| [
{
"created": "Sat, 4 Oct 2014 17:54:34 GMT",
"version": "v1"
},
{
"created": "Mon, 18 May 2015 13:00:14 GMT",
"version": "v2"
}
] | 2015-06-01 | [
[
"Krivoruchenko",
"M. I.",
""
]
] | The generalized Ward-Takahashi identity (gWTI) in the pion sector for broken isotopic symmetry is derived and used for the model-independent calculation of the longitudinal form factor $f_{-}$ of the $\pi_{e3}$ vector vertex. The on-shell $f_{-}$ is found to be proportional to the mass difference of the pions and the difference between the vector isospin $T = 1$ and scalar isospin $ T = 2 $ pion radii. A numerical estimate of the form factor yields a value two times higher than the previous estimate from the quark model. Off-shell form factors are known to be ambiguous because of the gauge dependence and the freedom in the parameterization of the fields. The near-mass-shell $f_{-}$ appears to be an exception, allowing for experimental verification of the consequences of the gWTI. We calculate the near-mass-shell $f_{-}$ using the gWTI and dispersion techniques. The results are discussed in the context of the conservation of vector current (CVC) hypothesis. |
hep-ph/0407332 | Felipe J. Llanes-Estrada | Felipe J. Llanes-Estrada (Complutense Madrid), Christian S. Fischer
(IPPP Durham), Reinhard Alkofer (Tubingen) | Semiperturbative construction for the quark-gluon vertex | 4 pages. Talk at QCD04, Montpellier July 5th 2004 | null | null | UNITU-THEP-8/04, IPPP/04/43, DCPT/04/86 | hep-ph | null | We construct a model for the quark-gluon vertex of Landau gauge QCD. This is
of twofold interest: on the one hand the quark-gluon interaction is at the
heart of quark confinement, on the other hand it is a central element in hadron
phenomenology based on QCD Greens functions. We employ the non-Abelian one-loop
diagram in perturbation theory, which is of order Nc. As a novelty we replace
the tree-level quark and gluon propagators in this diagram by their dressed
counterparts solving the Dyson-Schwinger equations. The Nc-suppressed Abelian
diagram is an order of magnitude smaller in various kinematics. We also study
the effect of ghost dressing factors on the vertex obtaining a construction in
good agreement with recent low-momentum lattice calculations.
| [
{
"created": "Thu, 29 Jul 2004 15:38:39 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Llanes-Estrada",
"Felipe J.",
"",
"Complutense Madrid"
],
[
"Fischer",
"Christian S.",
"",
"IPPP Durham"
],
[
"Alkofer",
"Reinhard",
"",
"Tubingen"
]
] | We construct a model for the quark-gluon vertex of Landau gauge QCD. This is of twofold interest: on the one hand the quark-gluon interaction is at the heart of quark confinement, on the other hand it is a central element in hadron phenomenology based on QCD Greens functions. We employ the non-Abelian one-loop diagram in perturbation theory, which is of order Nc. As a novelty we replace the tree-level quark and gluon propagators in this diagram by their dressed counterparts solving the Dyson-Schwinger equations. The Nc-suppressed Abelian diagram is an order of magnitude smaller in various kinematics. We also study the effect of ghost dressing factors on the vertex obtaining a construction in good agreement with recent low-momentum lattice calculations. |
2311.06452 | Yoshimasa Kurihara | Hieu Minh Tran, Huong Thu Nguyen, Yoshimasa Kurihara | Two Higgs doublet model fitting and $t\bar{t}b\bar{b}$ signal at the ILC | 20 pages, 8 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | One of the most straightforward extensions of the standard model (SM) is
having an additional Higgs doublet to the SM, namely the two Higgs doublet
models(THDM). In the type-I model, an additional Higgs doublet is introduced
that does not couple to any fermion via the Yukawa interaction. Considering
various theoretical and phenomenological constraints, we have found the
best-fitted parameter set in the type-I model using the minimum $\chi^2$ method
by scanning the model's parameter space. We show that this optimal parameter
set can be probed by precisely analyzing the decay processes $D^+ \rightarrow
\mu^+ \nu_\mu$, $B^0 \rightarrow K^* \mu^+ \mu^-$. Moreover, the decay channels
$h \rightarrow s\bar{s}$, $W^+W^-$ and $gg$ can be used to distinguish the
model from the SM. For a direct search of the model at future colliders, we
have proposed an investigation of the $e^+e^- \rightarrow t\bar{t} b\bar{b}$
process at the ILC to detect the new physics of the model. Considering the
initial state radiation correction and applying appropriate background cuts,
the calculation result of the scattering cross section shows that it is
feasible to observe a clear and unique signal in the $t\bar{b}$ invariant mass
distribution corresponding to the charged Higgs pair creations.
| [
{
"created": "Sat, 11 Nov 2023 01:08:22 GMT",
"version": "v1"
}
] | 2023-11-14 | [
[
"Tran",
"Hieu Minh",
""
],
[
"Nguyen",
"Huong Thu",
""
],
[
"Kurihara",
"Yoshimasa",
""
]
] | One of the most straightforward extensions of the standard model (SM) is having an additional Higgs doublet to the SM, namely the two Higgs doublet models(THDM). In the type-I model, an additional Higgs doublet is introduced that does not couple to any fermion via the Yukawa interaction. Considering various theoretical and phenomenological constraints, we have found the best-fitted parameter set in the type-I model using the minimum $\chi^2$ method by scanning the model's parameter space. We show that this optimal parameter set can be probed by precisely analyzing the decay processes $D^+ \rightarrow \mu^+ \nu_\mu$, $B^0 \rightarrow K^* \mu^+ \mu^-$. Moreover, the decay channels $h \rightarrow s\bar{s}$, $W^+W^-$ and $gg$ can be used to distinguish the model from the SM. For a direct search of the model at future colliders, we have proposed an investigation of the $e^+e^- \rightarrow t\bar{t} b\bar{b}$ process at the ILC to detect the new physics of the model. Considering the initial state radiation correction and applying appropriate background cuts, the calculation result of the scattering cross section shows that it is feasible to observe a clear and unique signal in the $t\bar{b}$ invariant mass distribution corresponding to the charged Higgs pair creations. |
hep-ph/9703311 | Kingman Cheung | V. Barger, Kingman Cheung, K. Hagiwara, D. Zeppenfeld | Contact Interactions and high-Q2 events in e^+ p collisions at HERA | RevTex, 12 pages, 4 figures. Slight changes in Figs.2 and 3 | Phys.Lett.B404:147-152,1997 | 10.1016/S0370-2693(97)00517-0 | MADPH-97-991 | hep-ph | null | We consider $e e q q$ contact interactions as a possible origin of an excess
of events above Standard Model predictions in $e^+ p \to e^+ jet$ at high $Q^2$
observed by the H1 and ZEUS collaborations at HERA. The HERA data prefer
chirality RL or LR contact terms and atomic physics parity violation
measurements severely limit parity-odd contact terms. With equal left-right and
right-left chirality interactions at an effective scale of order 3 TeV we are
able to reproduce the main features of the HERA data and still be consistent
with Drell-Yan pair production at the Tevatron and hadron production at LEP 2
and TRISTAN.
| [
{
"created": "Thu, 13 Mar 1997 02:46:51 GMT",
"version": "v1"
},
{
"created": "Mon, 31 Mar 1997 21:41:19 GMT",
"version": "v2"
}
] | 2016-09-06 | [
[
"Barger",
"V.",
""
],
[
"Cheung",
"Kingman",
""
],
[
"Hagiwara",
"K.",
""
],
[
"Zeppenfeld",
"D.",
""
]
] | We consider $e e q q$ contact interactions as a possible origin of an excess of events above Standard Model predictions in $e^+ p \to e^+ jet$ at high $Q^2$ observed by the H1 and ZEUS collaborations at HERA. The HERA data prefer chirality RL or LR contact terms and atomic physics parity violation measurements severely limit parity-odd contact terms. With equal left-right and right-left chirality interactions at an effective scale of order 3 TeV we are able to reproduce the main features of the HERA data and still be consistent with Drell-Yan pair production at the Tevatron and hadron production at LEP 2 and TRISTAN. |
hep-ph/0512178 | Bhag C. Chauhan | S. Dev, Sanjeev Kumar and Surender Verma | Model Independent Constraints on Non-electronic Flavors in the Solar
Boron Neutrino Flux | 8 pages and no figure | Mod.Phys.Lett.A21:1761-1768,2006 | 10.1142/S021773230602024X | null | hep-ph | null | We perform the most general model independent analysis of the latest 391-Day
Salt Phase SNO Data Set incorporating the Super-Kamiokande ES flux measurement
and obtain bounds on the antineutrino and sterile neutrino flux in the solar
$^{8}$B neutrino flux reaching the detectors on the earth. The muon/ tauon
antineutrino flux is found to be disallowed at 1.4$\sigma $ C.L. The sterile
flux is found to be non-zero at about 1.26 standard deviations.
| [
{
"created": "Wed, 14 Dec 2005 10:54:28 GMT",
"version": "v1"
}
] | 2010-11-05 | [
[
"Dev",
"S.",
""
],
[
"Kumar",
"Sanjeev",
""
],
[
"Verma",
"Surender",
""
]
] | We perform the most general model independent analysis of the latest 391-Day Salt Phase SNO Data Set incorporating the Super-Kamiokande ES flux measurement and obtain bounds on the antineutrino and sterile neutrino flux in the solar $^{8}$B neutrino flux reaching the detectors on the earth. The muon/ tauon antineutrino flux is found to be disallowed at 1.4$\sigma $ C.L. The sterile flux is found to be non-zero at about 1.26 standard deviations. |
1011.4944 | James Barnard | James Barnard | Solitonic supersymmetry restoration | 17 pages, 3 figures, minor comments added, accepted for publication
in JHEP | JHEP 1101:101,2011 | 10.1007/JHEP01(2011)101 | DCPT-10/63 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Q-balls are a possible feature of any model with a conserved, global U(1)
symmetry and no massless, charged scalars. It is shown that for a broad class
of models of metastable supersymmetry breaking they are extremely influential
on the vacuum lifetime and make seemingly viable vacua catastrophically short
lived. A net charge asymmetry is not required as there is often a significant
range of parameter space where statistical fluctuations alone are sufficient.
This effect is examined for two supersymmetry breaking scenarios. It is found
that models of minimal gauge mediation (which necessarily have a messenger
number U(1)) undergo a rapid, supersymmetry restoring phase transition unless
the messenger mass is greater than 10^8 GeV. Similarly the ISS model, in the
context of direct mediation, quickly decays unless the perturbative
superpotential coupling is greater than the Standard Model gauge couplings.
| [
{
"created": "Mon, 22 Nov 2010 21:00:06 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Jan 2011 12:06:10 GMT",
"version": "v2"
}
] | 2015-03-17 | [
[
"Barnard",
"James",
""
]
] | Q-balls are a possible feature of any model with a conserved, global U(1) symmetry and no massless, charged scalars. It is shown that for a broad class of models of metastable supersymmetry breaking they are extremely influential on the vacuum lifetime and make seemingly viable vacua catastrophically short lived. A net charge asymmetry is not required as there is often a significant range of parameter space where statistical fluctuations alone are sufficient. This effect is examined for two supersymmetry breaking scenarios. It is found that models of minimal gauge mediation (which necessarily have a messenger number U(1)) undergo a rapid, supersymmetry restoring phase transition unless the messenger mass is greater than 10^8 GeV. Similarly the ISS model, in the context of direct mediation, quickly decays unless the perturbative superpotential coupling is greater than the Standard Model gauge couplings. |
hep-ph/0407311 | Robert Thorne S. | R.S. Thorne, A.D. Martin, R.G. Roberts and W.J. Stirling | Update of MRST Parton Distributions | To appear in proceedings of "DIS 2004: XII International Workshop on
Deep Inelatic Scattering" (Strbske Pleso, Slovakia, April 2004). 6 pages, 3
figures | null | null | Cavendish-HEP-04/22 | hep-ph | null | I present a brief summary of the most important updates in the MRST
determinations of the NLO and NNLO parton distributions. I concentrate on
uncertainties due to input assumptions and possible theoretical corrections,
particularly isospin violation, QED corrections, NNLO and corrections at low
Q^2 and small x.
| [
{
"created": "Tue, 27 Jul 2004 16:45:33 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Thorne",
"R. S.",
""
],
[
"Martin",
"A. D.",
""
],
[
"Roberts",
"R. G.",
""
],
[
"Stirling",
"W. J.",
""
]
] | I present a brief summary of the most important updates in the MRST determinations of the NLO and NNLO parton distributions. I concentrate on uncertainties due to input assumptions and possible theoretical corrections, particularly isospin violation, QED corrections, NNLO and corrections at low Q^2 and small x. |
0803.0495 | Yasaman Farzan | Yasaman Farzan, Alexei Yu Smirnov | Coherence and oscillations of cosmic neutrinos | 31 pages; A discussion on "coherent broadening" is added | Nucl.Phys.B805:356-376,2008 | 10.1016/j.nuclphysb.2008.07.028 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | For cosmic neutrinos we study the conditions and the effects of the coherence
loss as well as coherent broadening of the spectrum. We evaluate the width of
the neutrino wavepacket produced by charged particles under various
circumstances: in an interaction-free environment, in a radiation-dominated
medium (typical of the sources of the gamma ray bursts) and in the presence of
a magnetic field. The effect of the magnetic field on the wavepacket size
appears to be more important than the scattering. If the magnetic field at the
source is larger than $\sim$10 Gauss, the coherence of neutrinos will be lost
while traveling over cosmological distances. Various applications of these
results have been considered. We find that for large magnetic fields ($B> 10^9$
Gauss) and high energies ($E_\nu>{\rm PeV}$), "coherent broadening" can modify
the energy spectrum of neutrinos. In the coherent case, averaging out the
oscillatory terms of the probabilities does not induce any statistical
uncertainty beyond what expected in the absence of these terms. A deviation
from the standard quantum mechanics that preserves average energy and unitarity
cannot alter the picture.
| [
{
"created": "Tue, 4 Mar 2008 16:54:25 GMT",
"version": "v1"
},
{
"created": "Mon, 1 Sep 2008 10:13:49 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Farzan",
"Yasaman",
""
],
[
"Smirnov",
"Alexei Yu",
""
]
] | For cosmic neutrinos we study the conditions and the effects of the coherence loss as well as coherent broadening of the spectrum. We evaluate the width of the neutrino wavepacket produced by charged particles under various circumstances: in an interaction-free environment, in a radiation-dominated medium (typical of the sources of the gamma ray bursts) and in the presence of a magnetic field. The effect of the magnetic field on the wavepacket size appears to be more important than the scattering. If the magnetic field at the source is larger than $\sim$10 Gauss, the coherence of neutrinos will be lost while traveling over cosmological distances. Various applications of these results have been considered. We find that for large magnetic fields ($B> 10^9$ Gauss) and high energies ($E_\nu>{\rm PeV}$), "coherent broadening" can modify the energy spectrum of neutrinos. In the coherent case, averaging out the oscillatory terms of the probabilities does not induce any statistical uncertainty beyond what expected in the absence of these terms. A deviation from the standard quantum mechanics that preserves average energy and unitarity cannot alter the picture. |
1808.09255 | Maryam Soleymaninia | Alireza Mohamaditabar, F. Taghavi-Shahri, Hamzeh Khanpour and Maryam
Soleymaninia | Determination of contributions from residual light charged hadrons to
inclusive charged hadrons from $e^+e^-$ annihilation data | 29 pages, 8 Tables and 7 figures, Accepted for publication in
European Physical Journal A | Eur. Phys. J. A 55 (2019) 185 | 10.1140/epja/i2019-12881-4 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper, we present an extraction of the contribution from the "{\it
residual}" light charged hadrons to the inclusive unidentified light charged
hadron fragmentation functions (FFs) at next-to-leading (NLO) and, for the
first time, at next-to-next-to-leading order (NNLO) accuracy in perturbative
QCD. Considering the contributions from charged pion, kaon and (anti)proton FFs
from recent {\tt NNFF1.0} analysis of charged hadron FFs, we determine the
small but efficient {\it residual} charged hadron FFs from QCD analysis of all
available single inclusive unidentified charged hadron data sets in
electron-positron ($e^+ e^-$) annihilations. The zero-mass variable flavor
number scheme (ZM-VFNS) has been applied to account the heavy flavor
contributions. The obtained optimum set of {\it residual} charged hadron FFs is
accompanied by the well-known Hessian technique to assess the uncertainties in
the extraction of these new sets of FFs. It is shown that the {\it residual}
contributions of charged hadron FFs have very important impact on the inclusive
charged hadron FFs and substantially on the quality and the reliability of the
QCD fit. Furthermore, this study shows that the {\it residual} contributions
become also sizable for the case of heavy quark FFs as well as for the $c$- and
$b$-tagged cross sections.
| [
{
"created": "Tue, 28 Aug 2018 12:42:58 GMT",
"version": "v1"
},
{
"created": "Mon, 7 Jan 2019 10:11:11 GMT",
"version": "v2"
},
{
"created": "Sun, 6 Oct 2019 09:07:27 GMT",
"version": "v3"
}
] | 2019-10-23 | [
[
"Mohamaditabar",
"Alireza",
""
],
[
"Taghavi-Shahri",
"F.",
""
],
[
"Khanpour",
"Hamzeh",
""
],
[
"Soleymaninia",
"Maryam",
""
]
] | In this paper, we present an extraction of the contribution from the "{\it residual}" light charged hadrons to the inclusive unidentified light charged hadron fragmentation functions (FFs) at next-to-leading (NLO) and, for the first time, at next-to-next-to-leading order (NNLO) accuracy in perturbative QCD. Considering the contributions from charged pion, kaon and (anti)proton FFs from recent {\tt NNFF1.0} analysis of charged hadron FFs, we determine the small but efficient {\it residual} charged hadron FFs from QCD analysis of all available single inclusive unidentified charged hadron data sets in electron-positron ($e^+ e^-$) annihilations. The zero-mass variable flavor number scheme (ZM-VFNS) has been applied to account the heavy flavor contributions. The obtained optimum set of {\it residual} charged hadron FFs is accompanied by the well-known Hessian technique to assess the uncertainties in the extraction of these new sets of FFs. It is shown that the {\it residual} contributions of charged hadron FFs have very important impact on the inclusive charged hadron FFs and substantially on the quality and the reliability of the QCD fit. Furthermore, this study shows that the {\it residual} contributions become also sizable for the case of heavy quark FFs as well as for the $c$- and $b$-tagged cross sections. |
2308.05607 | Zuowei Liu | Mingxuan Du, Rundong Fang, Zuowei Liu, Wenxi Lu, Zicheng Ye | Probing invisible dark photon models via atmospheric collisions | 6 pages, 2 figures | null | null | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Atmospheric collisions can copiously produce dark sector particles in the
invisible dark photon model, leading to detectable signals in underground
neutrino detectors. We consider the dark photon model with the mass mixing
mechanism and use the Super-K detector to detect the electron recoil events
caused by the atmospherically produced dark sector particles within the model.
We find that the combined data from four Super-K runs yield new leading
constraints for the invisible dark photon in the mass range of $\sim(0.5-1.4)$
GeV, surpassing the constraints from NA64, BaBar, and searches for millicharged
particles.
| [
{
"created": "Thu, 10 Aug 2023 14:36:58 GMT",
"version": "v1"
}
] | 2023-08-11 | [
[
"Du",
"Mingxuan",
""
],
[
"Fang",
"Rundong",
""
],
[
"Liu",
"Zuowei",
""
],
[
"Lu",
"Wenxi",
""
],
[
"Ye",
"Zicheng",
""
]
] | Atmospheric collisions can copiously produce dark sector particles in the invisible dark photon model, leading to detectable signals in underground neutrino detectors. We consider the dark photon model with the mass mixing mechanism and use the Super-K detector to detect the electron recoil events caused by the atmospherically produced dark sector particles within the model. We find that the combined data from four Super-K runs yield new leading constraints for the invisible dark photon in the mass range of $\sim(0.5-1.4)$ GeV, surpassing the constraints from NA64, BaBar, and searches for millicharged particles. |
1804.11211 | Luciano Petruzziello | M. Blasone, G. Lambiase, G. G. Luciano and L. Petruzziello | Neutrino mixing and General Covariance in the inverse beta decay | null | null | 10.22323/1.318.0198 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We review recent developments on the role of neutrino mixing in the inverse
beta decay of accelerated protons. We show that calculations in the inertial
and comoving frames agree (thus preserving General Covariance) only when taking
neutrino asymptotic states to be flavor (rather than mass) eigenstates. Our
conclusions are valid in the approximation in which Pontecorvo states are
correctly representing neutrino flavor states. We speculate about the general
case involving exact flavor states and finally comment on other approaches
recently appeared in literature.
| [
{
"created": "Fri, 27 Apr 2018 14:03:38 GMT",
"version": "v1"
}
] | 2018-08-27 | [
[
"Blasone",
"M.",
""
],
[
"Lambiase",
"G.",
""
],
[
"Luciano",
"G. G.",
""
],
[
"Petruzziello",
"L.",
""
]
] | We review recent developments on the role of neutrino mixing in the inverse beta decay of accelerated protons. We show that calculations in the inertial and comoving frames agree (thus preserving General Covariance) only when taking neutrino asymptotic states to be flavor (rather than mass) eigenstates. Our conclusions are valid in the approximation in which Pontecorvo states are correctly representing neutrino flavor states. We speculate about the general case involving exact flavor states and finally comment on other approaches recently appeared in literature. |
hep-ph/0607316 | Thorsten Ewerth | H.M. Asatrian (Yerevan Phys. Inst.), T. Ewerth (Bern U.), A. Ferroglia
(Freiburg U.), P. Gambino (INFN, Turin & Turin U.), C. Greub (Bern U.) | Magnetic dipole operator contributions to the photon energy spectrum in
anti-B -> X(s) gamma at O(alpha(s)^2) | 18 pages, uses axodraw.sty | Nucl.Phys.B762:212-228,2007 | 10.1016/j.nuclphysb.2006.11.002 | Freiburg-THEP 06/11, DFTT-13/2006 | hep-ph | null | We compute the O(\alpha_s^2) contributions to the photon energy spectrum of
the inclusive decay \bar{B} -> X_s \gamma associated with the magnetic penguin
operator O_7. They are an essential part of the ongoing NNLO calculation of
this important decay. We use two different methods to evaluate the master
integrals, one based on the differential equation approach and the other on
sector decomposition, leading to identical results which in turn agree with
those of a recent independent calculation by Melnikov and Mitov. We study the
numerical relevance of this set of NNLO contributions in the photon energy
spectrum and discuss the change of bottom quark mass scheme.
| [
{
"created": "Fri, 28 Jul 2006 13:08:54 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Asatrian",
"H. M.",
"",
"Yerevan Phys. Inst."
],
[
"Ewerth",
"T.",
"",
"Bern U."
],
[
"Ferroglia",
"A.",
"",
"Freiburg U."
],
[
"Gambino",
"P.",
"",
"INFN, Turin & Turin U."
],
[
"Greub",
"C.",
"",
"Bern U."
]
] | We compute the O(\alpha_s^2) contributions to the photon energy spectrum of the inclusive decay \bar{B} -> X_s \gamma associated with the magnetic penguin operator O_7. They are an essential part of the ongoing NNLO calculation of this important decay. We use two different methods to evaluate the master integrals, one based on the differential equation approach and the other on sector decomposition, leading to identical results which in turn agree with those of a recent independent calculation by Melnikov and Mitov. We study the numerical relevance of this set of NNLO contributions in the photon energy spectrum and discuss the change of bottom quark mass scheme. |
1712.00187 | Sa\'ul Hern\'andez Ortiz Ph.D | A. Ayala, J. A. Flores, L. A. Hernandez and S. Hernandez-Ortiz | Locating the critical end point using the linear sigma model coupled to
quarks | 8 pages, 2 figures, conference paper from ISMD 2017 | null | 10.1051/epjconf/201817202003 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We use the linear sigma model coupled to quarks to compute the effective
potential beyond the mean field approximation, including the contribution of
the ring diagrams at finite temperature and baryon density. We determine the
model couplings and use them to study the phase diagram in the baryon chemical
potential-temperature plane and to locate the Critical End Point.
| [
{
"created": "Fri, 1 Dec 2017 04:39:56 GMT",
"version": "v1"
}
] | 2018-03-14 | [
[
"Ayala",
"A.",
""
],
[
"Flores",
"J. A.",
""
],
[
"Hernandez",
"L. A.",
""
],
[
"Hernandez-Ortiz",
"S.",
""
]
] | We use the linear sigma model coupled to quarks to compute the effective potential beyond the mean field approximation, including the contribution of the ring diagrams at finite temperature and baryon density. We determine the model couplings and use them to study the phase diagram in the baryon chemical potential-temperature plane and to locate the Critical End Point. |
hep-ph/9903224 | Nima Arkani Hamed | Nima Arkani-Hamed, Savas Dimopoulos, Nemanja Kaloper and John
March-Russell | Rapid Asymmetric Inflation and Early Cosmology in Theories with
Sub-Millimeter Dimensions | 47 pages, latex | Nucl.Phys. B567 (2000) 189-228 | 10.1016/S0550-3213(99)00667-7 | CERN-TH/99-38, SLAC-PUB-8068, SU-ITP-98/68 | hep-ph hep-th | null | It was recently pointed out that the fundamental Planck mass could be close
to the TeV scale with the observed weakness of gravity at long distances being
due the existence of new sub-millimeter spatial dimensions. In this picture the
standard model fields are localized to a $(3+1)$-dimensional wall or
``3-brane''. We show that in such theories there exist attractive models of
inflation that occur while the size of the new dimensions are still small. We
show that it is easy to produce the required number of efoldings, and further
that the density perturbations $\delta\rho/\rho$ as measured by COBE can be
easily reproduced, both in overall magnitude and in their approximately
scale-invariant spectrum. In the minimal approach, the inflaton field is just
the moduli describing the size of the internal dimensions, the role of the
inflationary potential being played by the stabilizing potential of the
internal space. We show that under quite general conditions, the inflationary
era is followed by an epoch of contraction of our world on the brane, while the
internal dimensions slowly expand to their stabilization radius. We find a set
of exact solutions which describe this behavior, generalizing the well-known
Kasner solutions. During this phase, the production of bulk gravitons remains
suppressed. The period of contraction is terminated by the blue-shifting of
Hawking radiation left on our wall at the end of the inflationary de Sitter
phase. The temperature to which this is reheated is consistent with the
normalcy bounds. We give a precise definition of the radion moduli problem.
| [
{
"created": "Tue, 2 Mar 1999 21:37:16 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Arkani-Hamed",
"Nima",
""
],
[
"Dimopoulos",
"Savas",
""
],
[
"Kaloper",
"Nemanja",
""
],
[
"March-Russell",
"John",
""
]
] | It was recently pointed out that the fundamental Planck mass could be close to the TeV scale with the observed weakness of gravity at long distances being due the existence of new sub-millimeter spatial dimensions. In this picture the standard model fields are localized to a $(3+1)$-dimensional wall or ``3-brane''. We show that in such theories there exist attractive models of inflation that occur while the size of the new dimensions are still small. We show that it is easy to produce the required number of efoldings, and further that the density perturbations $\delta\rho/\rho$ as measured by COBE can be easily reproduced, both in overall magnitude and in their approximately scale-invariant spectrum. In the minimal approach, the inflaton field is just the moduli describing the size of the internal dimensions, the role of the inflationary potential being played by the stabilizing potential of the internal space. We show that under quite general conditions, the inflationary era is followed by an epoch of contraction of our world on the brane, while the internal dimensions slowly expand to their stabilization radius. We find a set of exact solutions which describe this behavior, generalizing the well-known Kasner solutions. During this phase, the production of bulk gravitons remains suppressed. The period of contraction is terminated by the blue-shifting of Hawking radiation left on our wall at the end of the inflationary de Sitter phase. The temperature to which this is reheated is consistent with the normalcy bounds. We give a precise definition of the radion moduli problem. |
hep-ph/9802337 | Daniel Enstrom | Daniel Enstrom | Astrophysical Aspects of Quark-Gluon Plasma | Latex, 75 pages, 19 postscript figures | null | null | ISSN:1402-1617, ISRN:LTU-EX--97/366--SE | hep-ph | null | This M.Sc. thesis in Engineering Physics is an overview of the present theory
of quark-gluon plasma (QGP) as well as an analysis of the stability criterion
for possible stable cosmic QGP objects left over from the quark-hadron
transition in the early Universe. It covers fundamental ideas of the formation
and decay of the plasma, including the standard model, QCD, and the MIT bag
model. I discuss the equation of state of a QGP and the possible signatures for
a plasma created in heavy-ion collisions. Astrophysical aspects of QGP are put
forward, including compact stars and the quark-hadron transition in the early
Universe. The possible role of QGP objects as cosmic dark matter is mentioned.
The analytic part is an investigation of possible stability among cosmic QGP
objects from the early Universe. A model is suggested where a pressure balance
makes a QGP stable against gravitational contraction and hadronization. The
mass/radius relationship for stability also forbids a direct gravitational
collapse. Finally, the possibility of stable cosmic QGP objects is critically
discussed.
| [
{
"created": "Tue, 17 Feb 1998 14:12:41 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Mar 1998 07:30:12 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Enstrom",
"Daniel",
""
]
] | This M.Sc. thesis in Engineering Physics is an overview of the present theory of quark-gluon plasma (QGP) as well as an analysis of the stability criterion for possible stable cosmic QGP objects left over from the quark-hadron transition in the early Universe. It covers fundamental ideas of the formation and decay of the plasma, including the standard model, QCD, and the MIT bag model. I discuss the equation of state of a QGP and the possible signatures for a plasma created in heavy-ion collisions. Astrophysical aspects of QGP are put forward, including compact stars and the quark-hadron transition in the early Universe. The possible role of QGP objects as cosmic dark matter is mentioned. The analytic part is an investigation of possible stability among cosmic QGP objects from the early Universe. A model is suggested where a pressure balance makes a QGP stable against gravitational contraction and hadronization. The mass/radius relationship for stability also forbids a direct gravitational collapse. Finally, the possibility of stable cosmic QGP objects is critically discussed. |
1012.5099 | Ze'ev Surujon | Masahiro Ibe, Arvind Rajaraman, Ze'ev Surujon | Does Supersymmetry Require Two Higgs Doublets? | v2: submitted to PLB | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss a new class of low energy supersymmetric models in which the Higgs
sector includes a single doublet, for example H_u, but not H_d. Chiral gauge
anomalies are canceled against new electroweak-charged states. We discuss the
main challenges in building such models, and present several models where these
issues are addressed. The resulting phenomenology can be distinguished from
that of the MSSM in a number of ways, most notably in physics related to
down-type quarks and charged leptons. As a first step toward a chiral Higgs
sector, we discuss the scenario of an inert H_d doublet. We show that a UV
completion of such model naturally includes dark matter with novel, flavorful
couplings to SM quarks.
| [
{
"created": "Wed, 22 Dec 2010 20:58:54 GMT",
"version": "v1"
},
{
"created": "Wed, 16 Nov 2011 10:10:42 GMT",
"version": "v2"
}
] | 2011-11-17 | [
[
"Ibe",
"Masahiro",
""
],
[
"Rajaraman",
"Arvind",
""
],
[
"Surujon",
"Ze'ev",
""
]
] | We discuss a new class of low energy supersymmetric models in which the Higgs sector includes a single doublet, for example H_u, but not H_d. Chiral gauge anomalies are canceled against new electroweak-charged states. We discuss the main challenges in building such models, and present several models where these issues are addressed. The resulting phenomenology can be distinguished from that of the MSSM in a number of ways, most notably in physics related to down-type quarks and charged leptons. As a first step toward a chiral Higgs sector, we discuss the scenario of an inert H_d doublet. We show that a UV completion of such model naturally includes dark matter with novel, flavorful couplings to SM quarks. |
1902.05936 | Adam Falkowski | Adam Falkowski and Riccardo Rattazzi | Which EFT | 17 pages; v2: comments and references added, published version | null | 10.1007/JHEP10(2019)255 | LPT Orsay 19-05 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We classify effective field theory (EFT) deformations of the Standard Model
(SM) according to the analyticity property of the Lagrangian as a function of
the Higgs doublet H. Our distinction in analytic and non-analytic corresponds
to the more familiar one between linearly and non-linearly realized electroweak
symmetry, but offers deeper physical insight. From the UV perspective,
non-analyticity occurs when the new states acquire mass from electroweak
symmetry breaking, and thus cannot be decoupled to arbitrarily high scales.
This is reflected in the IR by the anomalous growth of the interaction strength
for processes involving many Higgs bosons and longitudinally polarized massive
vectors, with a breakdown of the EFT description below a scale $O(4 \pi v)$.
Conversely, analyticity occurs when new physics can be pushed parametrically
above the electroweak scale.
We illustrate the physical distinction between these two EFT families by
discussing Higgs boson self-interactions. In the analytic case, at the price of
some unnaturalness in the Higgs potential, there exists space for $O(1)$
deviations of the cubic coupling, compatible with single Higgs and electroweak
precision measurements, and with new particles out of the direct LHC reach.
Larger deviations are possible, but subject to less robust assumptions about
higher-dimensional operators in the Higgs potential. On the other hand, when
the cubic coupling is produced by a non-analytic deformation of the SM, we show
by an explicit calculation that the theory reaches strong coupling at $O(4 \pi
v)$, quite independently of the magnitude of the cubic enhancement.
| [
{
"created": "Fri, 15 Feb 2019 18:36:42 GMT",
"version": "v1"
},
{
"created": "Fri, 15 Nov 2019 13:33:42 GMT",
"version": "v2"
}
] | 2020-01-08 | [
[
"Falkowski",
"Adam",
""
],
[
"Rattazzi",
"Riccardo",
""
]
] | We classify effective field theory (EFT) deformations of the Standard Model (SM) according to the analyticity property of the Lagrangian as a function of the Higgs doublet H. Our distinction in analytic and non-analytic corresponds to the more familiar one between linearly and non-linearly realized electroweak symmetry, but offers deeper physical insight. From the UV perspective, non-analyticity occurs when the new states acquire mass from electroweak symmetry breaking, and thus cannot be decoupled to arbitrarily high scales. This is reflected in the IR by the anomalous growth of the interaction strength for processes involving many Higgs bosons and longitudinally polarized massive vectors, with a breakdown of the EFT description below a scale $O(4 \pi v)$. Conversely, analyticity occurs when new physics can be pushed parametrically above the electroweak scale. We illustrate the physical distinction between these two EFT families by discussing Higgs boson self-interactions. In the analytic case, at the price of some unnaturalness in the Higgs potential, there exists space for $O(1)$ deviations of the cubic coupling, compatible with single Higgs and electroweak precision measurements, and with new particles out of the direct LHC reach. Larger deviations are possible, but subject to less robust assumptions about higher-dimensional operators in the Higgs potential. On the other hand, when the cubic coupling is produced by a non-analytic deformation of the SM, we show by an explicit calculation that the theory reaches strong coupling at $O(4 \pi v)$, quite independently of the magnitude of the cubic enhancement. |
0707.3718 | Janusz Rosiek | Athanasios Dedes, Howard E. Haber and Janusz Rosiek | Seesaw mechanism in the sneutrino sector and its consequences | 69 pages, 5 figures, uses axodraw.sty. Version accepted for
publication in JHEP: some comments and one more Appendix with additional
discussion added, references updated | JHEP 0711:059,2007 | 10.1088/1126-6708/2007/11/059 | IPPP-07-16, CPT-07-32, SCIPP-07/10 | hep-ph | null | The seesaw-extended MSSM provides a framework in which the observed light
neutrino masses and mixing angles can be generated in the context of a natural
theory for the TeV-scale. Sneutrino-mixing phenomena provide valuable tools for
connecting the physics of neutrinos and supersymmetry. We examine the
theoretical structure of the seesaw-extended MSSM, retaining the full
complexity of three generations of neutrinos and sneutrinos. In this general
framework, new flavor-changing and CP-violating sneutrino processes are
allowed, and are parameterized in terms of two $3\times 3$ matrices that
respectively preserve and violate lepton number. The elements of these matrices
can be bounded by analyzing the rate for rare flavor-changing decays of charged
leptons and the one-loop contribution to neutrino masses. In the former case,
new contributions arise in the seesaw extended model which are not present in
the ordinary MSSM. In the latter case, sneutrino--antisneutrino mixing
generates the leading correction at one-loop to neutrino masses, and could
provide the origin of the observed texture of the light neutrino mass matrix.
Finally, we derive general formulae for sneutrino--antisneutrino oscillations
and sneutrino flavor-oscillations. Unfortunately, neither oscillation phenomena
is likely to be observable at future colliders.
| [
{
"created": "Wed, 25 Jul 2007 11:57:25 GMT",
"version": "v1"
},
{
"created": "Wed, 1 Aug 2007 09:27:39 GMT",
"version": "v2"
},
{
"created": "Wed, 7 Nov 2007 21:57:11 GMT",
"version": "v3"
}
] | 2009-01-06 | [
[
"Dedes",
"Athanasios",
""
],
[
"Haber",
"Howard E.",
""
],
[
"Rosiek",
"Janusz",
""
]
] | The seesaw-extended MSSM provides a framework in which the observed light neutrino masses and mixing angles can be generated in the context of a natural theory for the TeV-scale. Sneutrino-mixing phenomena provide valuable tools for connecting the physics of neutrinos and supersymmetry. We examine the theoretical structure of the seesaw-extended MSSM, retaining the full complexity of three generations of neutrinos and sneutrinos. In this general framework, new flavor-changing and CP-violating sneutrino processes are allowed, and are parameterized in terms of two $3\times 3$ matrices that respectively preserve and violate lepton number. The elements of these matrices can be bounded by analyzing the rate for rare flavor-changing decays of charged leptons and the one-loop contribution to neutrino masses. In the former case, new contributions arise in the seesaw extended model which are not present in the ordinary MSSM. In the latter case, sneutrino--antisneutrino mixing generates the leading correction at one-loop to neutrino masses, and could provide the origin of the observed texture of the light neutrino mass matrix. Finally, we derive general formulae for sneutrino--antisneutrino oscillations and sneutrino flavor-oscillations. Unfortunately, neither oscillation phenomena is likely to be observable at future colliders. |
2403.03252 | Bibhushan Shakya | Gian F. Giudice, Hyun Min Lee, Alex Pomarol, Bibhushan Shakya | Nonthermal Heavy Dark Matter from a First-Order Phase Transition | 41 pages, 3 figures | null | null | CERN-TH-2024-031, DESY-24-031 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study nonthermal production of heavy dark matter from the dynamics of the
background scalar field during a first-order phase transition, predominantly
from bubble collisions. In scenarios where bubble walls achieve runaway
behavior and get boosted to very high energies, we find that it is possible to
produce dark matter with mass several orders of magnitude above the symmetry
breaking scale or the highest temperature ever reached by the thermal plasma.
We also demonstrate that the existing formalism for calculating particle
production from bubble dynamics in a first-order phase transition is not gauge
invariant, and can lead to spurious results. While a rigorous and complete
resolution of this problem is still lacking, we provide a practical
prescription for the computation that avoids unphysical contributions and
should provide reliable order-of-magnitude estimates of this effect.
Furthermore, we point out the importance of three-body decays of the background
field excitations into scalars and gauge bosons, which provide the dominant
contributions at energy scales above the scale of symmetry breaking. Using our
improved results, we find that scalar, fermion, and vector dark matter are all
viable across a large range of mass scales, from O(10) TeV to a few orders of
magnitude below the Planck scale, and the corresponding phase transitions can
be probed with current and future gravitational wave experiments.
| [
{
"created": "Tue, 5 Mar 2024 19:00:02 GMT",
"version": "v1"
}
] | 2024-03-07 | [
[
"Giudice",
"Gian F.",
""
],
[
"Lee",
"Hyun Min",
""
],
[
"Pomarol",
"Alex",
""
],
[
"Shakya",
"Bibhushan",
""
]
] | We study nonthermal production of heavy dark matter from the dynamics of the background scalar field during a first-order phase transition, predominantly from bubble collisions. In scenarios where bubble walls achieve runaway behavior and get boosted to very high energies, we find that it is possible to produce dark matter with mass several orders of magnitude above the symmetry breaking scale or the highest temperature ever reached by the thermal plasma. We also demonstrate that the existing formalism for calculating particle production from bubble dynamics in a first-order phase transition is not gauge invariant, and can lead to spurious results. While a rigorous and complete resolution of this problem is still lacking, we provide a practical prescription for the computation that avoids unphysical contributions and should provide reliable order-of-magnitude estimates of this effect. Furthermore, we point out the importance of three-body decays of the background field excitations into scalars and gauge bosons, which provide the dominant contributions at energy scales above the scale of symmetry breaking. Using our improved results, we find that scalar, fermion, and vector dark matter are all viable across a large range of mass scales, from O(10) TeV to a few orders of magnitude below the Planck scale, and the corresponding phase transitions can be probed with current and future gravitational wave experiments. |
0705.4264 | Antonio Pich | Antonio Pich | The Standard Model of Electroweak Interactions | Updated version of the lectures given at the 2006 European School of
High Energy Physics (Aronsborg, Sweden, 18 June - 1 July 2006) and at the 4th
CERN - CLAF School of High Energy Physics (Vina del Mar, Chile, 18 February -
3 March 2007). 50 pages, 36 figures | null | null | IFIC/07-27, FTUV/07-0529 | hep-ph hep-ex | null | Gauge invariance is a powerful tool to determine the dynamics of the
electroweak and strong forces. The particle content, structure and symmetries
of the Standard Model Lagrangian are discussed. Special emphasis is given to
the many phenomenological tests which have established this theoretical
framework as the Standard Theory of electroweak interactions.
| [
{
"created": "Tue, 29 May 2007 18:09:11 GMT",
"version": "v1"
}
] | 2007-06-13 | [
[
"Pich",
"Antonio",
""
]
] | Gauge invariance is a powerful tool to determine the dynamics of the electroweak and strong forces. The particle content, structure and symmetries of the Standard Model Lagrangian are discussed. Special emphasis is given to the many phenomenological tests which have established this theoretical framework as the Standard Theory of electroweak interactions. |
1803.06885 | Muhammad Jamil Aslam | Aqsa Nasrullah, M. Jamil Aslam and Saba Shafaq | Analysis of Angular Observables of $\Lambda_b \to \Lambda (\to
p\pi)\mu^{+}\mu^{-}$ Decay in Standard and $Z^{\prime}$ Models | 28 pages, 4 figures, A version accepted for Publication in PTEP | Prog Theor Exp Phys (2018) | 10.1093/ptep/pty043 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In 2015, the LHCb collaboration has measured $\frac{d{\mathcal{B}}}{dq^2}$,
the lepton- and hadron-side forward-backward asymmetries, denoted by
$A^\ell_{FB}$ and $A^{\Lambda}_{FB}$, respectively in the range $15 < q^2(=s) <
20$ GeV$^2$ with 3 fb$^{-1}$ of data. Motivated by these measurements, we
perform an analysis of $q^2$ dependent $\Lambda_b \to \Lambda (\to p \pi )
\mu^+\mu^-$ angular observables at large- and low-recoil in the SM and in a
family non-universal $Z^{\prime}$ model. In the present study we use the
recently performed high-precision lattice QCD calculations of the form factors
that have well controlled uncertainties especially in $15 < s < 20$ GeV$^2$
bin. Using the full four-folded angular distribution of $\Lambda_b \to \Lambda
(\to p \pi ) \mu^+\mu^-$ decay, firstly we calculate the values of these
measured quantitites in the SM and compare their numerical values with the
measurements in appropriate bins of $s$. In case of the possible discrepancy
between the SM prediction and measurements, we try to see if these can be
accommodated though the extra neutral $Z^{\prime}$ boson. In addition, the
fraction of longitudinal polarization of the dimuon $F_{L}$ is measured to be
$0.61^{+0.11}_{-0.14}\pm 0.03$ in $15 < s < 20$ GeV$^2$ at the LHCb. We find
that in this bin the value found in the $Z^{\prime}$ model is close to the
observed values. After comparing the results of these observables, we have
proposed a number of other observables whose values are calculated in different
bins of $s$ in the SM and $Z^{\prime}$ model. We illustrate that the
experimental observations of these observables in several bins of $s$ can help
to test the predictions of the SM and unravel NP contributions arises due to
$Z^{\prime}$ model in these decays.
| [
{
"created": "Mon, 19 Mar 2018 12:16:14 GMT",
"version": "v1"
}
] | 2019-12-06 | [
[
"Nasrullah",
"Aqsa",
""
],
[
"Aslam",
"M. Jamil",
""
],
[
"Shafaq",
"Saba",
""
]
] | In 2015, the LHCb collaboration has measured $\frac{d{\mathcal{B}}}{dq^2}$, the lepton- and hadron-side forward-backward asymmetries, denoted by $A^\ell_{FB}$ and $A^{\Lambda}_{FB}$, respectively in the range $15 < q^2(=s) < 20$ GeV$^2$ with 3 fb$^{-1}$ of data. Motivated by these measurements, we perform an analysis of $q^2$ dependent $\Lambda_b \to \Lambda (\to p \pi ) \mu^+\mu^-$ angular observables at large- and low-recoil in the SM and in a family non-universal $Z^{\prime}$ model. In the present study we use the recently performed high-precision lattice QCD calculations of the form factors that have well controlled uncertainties especially in $15 < s < 20$ GeV$^2$ bin. Using the full four-folded angular distribution of $\Lambda_b \to \Lambda (\to p \pi ) \mu^+\mu^-$ decay, firstly we calculate the values of these measured quantitites in the SM and compare their numerical values with the measurements in appropriate bins of $s$. In case of the possible discrepancy between the SM prediction and measurements, we try to see if these can be accommodated though the extra neutral $Z^{\prime}$ boson. In addition, the fraction of longitudinal polarization of the dimuon $F_{L}$ is measured to be $0.61^{+0.11}_{-0.14}\pm 0.03$ in $15 < s < 20$ GeV$^2$ at the LHCb. We find that in this bin the value found in the $Z^{\prime}$ model is close to the observed values. After comparing the results of these observables, we have proposed a number of other observables whose values are calculated in different bins of $s$ in the SM and $Z^{\prime}$ model. We illustrate that the experimental observations of these observables in several bins of $s$ can help to test the predictions of the SM and unravel NP contributions arises due to $Z^{\prime}$ model in these decays. |
2004.08890 | Simonetta Liuti | Brandon Kriesten and Simonetta Liuti | Theory of Deeply Virtual Compton Scattering off the Unpolarized Proton | 22 pages, 15 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Using the helicity amplitudes formalism, we study deeply virtual exclusive
electron photo-production off an unpolarized nucleon target, $ep \rightarrow e'
p' \gamma$, through a range of kinematics both in the fixed target setting with
initial electron energies of 6 GeV, 11 GeV and 24 GeV, and for an electron ion
collider. We reformulate the cross section bringing to the forefront the
defining features of the $ep \rightarrow e'p'\gamma$ process, where the
observables are expressed as bilinear products of the independent helicity
amplitudes which completely describe it in terms of the electric, magnetic and
axial currents of the nucleon. %This structure is reflected in different ways
in the Deeply virtual Compton scattering and Bethe-Heitler parts of the cross
section. % These contributions are checked against the Fourier harmonics-based
formalism which has provided so far the underlying mathematical framework to
study Deeply virtual Compton scattering and related experiments. Using
theoretical model calculations of the twist-two generalized parton
distributions, $ H$, $E$, $\widetilde{H}$ and $\widetilde{E}$, we uncover large
discrepancies between the harmonic series and our proposed framework. Most
importantly, these numerical differences appear in the intermediate $Q^2$ range
which represents a sweet spot for extracting generalized parton distributions
from data. % We provide a framework that is ideal, on one side, to study and
compare the different conventions that can be used to describe the leading
order contribution to DVCS in QCD, while on the other, it facilitates a
quantitative extraction of physically meaningful information from experiment
through traceable and controllable approximations in the intermediate $Q^2$
region.
| [
{
"created": "Sun, 19 Apr 2020 16:06:03 GMT",
"version": "v1"
},
{
"created": "Wed, 4 Nov 2020 18:21:48 GMT",
"version": "v2"
},
{
"created": "Wed, 19 May 2021 04:12:21 GMT",
"version": "v3"
},
{
"created": "Fri, 19 Nov 2021 22:20:35 GMT",
"version": "v4"
}
] | 2021-11-23 | [
[
"Kriesten",
"Brandon",
""
],
[
"Liuti",
"Simonetta",
""
]
] | Using the helicity amplitudes formalism, we study deeply virtual exclusive electron photo-production off an unpolarized nucleon target, $ep \rightarrow e' p' \gamma$, through a range of kinematics both in the fixed target setting with initial electron energies of 6 GeV, 11 GeV and 24 GeV, and for an electron ion collider. We reformulate the cross section bringing to the forefront the defining features of the $ep \rightarrow e'p'\gamma$ process, where the observables are expressed as bilinear products of the independent helicity amplitudes which completely describe it in terms of the electric, magnetic and axial currents of the nucleon. %This structure is reflected in different ways in the Deeply virtual Compton scattering and Bethe-Heitler parts of the cross section. % These contributions are checked against the Fourier harmonics-based formalism which has provided so far the underlying mathematical framework to study Deeply virtual Compton scattering and related experiments. Using theoretical model calculations of the twist-two generalized parton distributions, $ H$, $E$, $\widetilde{H}$ and $\widetilde{E}$, we uncover large discrepancies between the harmonic series and our proposed framework. Most importantly, these numerical differences appear in the intermediate $Q^2$ range which represents a sweet spot for extracting generalized parton distributions from data. % We provide a framework that is ideal, on one side, to study and compare the different conventions that can be used to describe the leading order contribution to DVCS in QCD, while on the other, it facilitates a quantitative extraction of physically meaningful information from experiment through traceable and controllable approximations in the intermediate $Q^2$ region. |
1408.2500 | Michal Czakon | M. Czakon and D. Heymes | Four-dimensional formulation of the sector-improved residue subtraction
scheme | 60 pages, 5 figures, 9 tables | null | 10.1016/j.nuclphysb.2014.11.006 | TTK-14-16 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Four years ago, one of us introduced a novel subtraction scheme for the
evaluation of double-real radiation contributions to cross sections at
next-to-next-to-leading order (NNLO) in QCD. This approach, named SecToR
Improved Phase sPacE for Real radiation (STRIPPER), has already found several
non-trivial applications. In particular, it has allowed for the determination
of NNLO corrections to hadronic top-quark pair production, fully differential
top-quark decays, inclusive semileptonic charmless b-quark decays, associated
Higgs boson and jet production in gluon fusion, muon decay spin asymmetry, and
t-channel single-top production. Common to these calculations was the use of
conventional dimensional regularization (CDR). In this publication, we present
a complete formulation of the subtraction scheme for arbitrary processes with
any number of colored partons in the final state, and up to two partons in the
initial state. Furthermore, we modify the integrated subtraction terms of the
double-real radiation to enable the introduction of the 't Hooft-Veltman
version of dimensional regularization (HV), in which resolved states are
four-dimensional. We demonstrate the correctness of our approach on the example
of top-quark pair production in the gluon fusion channel.
| [
{
"created": "Mon, 11 Aug 2014 19:33:57 GMT",
"version": "v1"
}
] | 2015-06-22 | [
[
"Czakon",
"M.",
""
],
[
"Heymes",
"D.",
""
]
] | Four years ago, one of us introduced a novel subtraction scheme for the evaluation of double-real radiation contributions to cross sections at next-to-next-to-leading order (NNLO) in QCD. This approach, named SecToR Improved Phase sPacE for Real radiation (STRIPPER), has already found several non-trivial applications. In particular, it has allowed for the determination of NNLO corrections to hadronic top-quark pair production, fully differential top-quark decays, inclusive semileptonic charmless b-quark decays, associated Higgs boson and jet production in gluon fusion, muon decay spin asymmetry, and t-channel single-top production. Common to these calculations was the use of conventional dimensional regularization (CDR). In this publication, we present a complete formulation of the subtraction scheme for arbitrary processes with any number of colored partons in the final state, and up to two partons in the initial state. Furthermore, we modify the integrated subtraction terms of the double-real radiation to enable the introduction of the 't Hooft-Veltman version of dimensional regularization (HV), in which resolved states are four-dimensional. We demonstrate the correctness of our approach on the example of top-quark pair production in the gluon fusion channel. |
2304.05643 | Minoru Tanaka | Xiaolong Deng, Florentin Jaffredo, Minoru Tanaka | Rare Leptonic Processes Induced by Massless Dark Photon | 13 pages, 4 figures, discussion on a UV model and 3 references added | null | 10.1016/j.physletb.2023.138035 | OU-HET-1182 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We introduce a dark photon considering a U(1) gauge extension of the standard
model in particle physics. Provided that the extra U(1) symmetry is unbroken,
the dark photon is massless and has no coupling to the standard electromagnetic
current. Higher-dimensional operators describe interactions of the massless
dark photon with particles in the standard model. We investigate the
interactions of the massless dark photon with charged leptons via dipole
operators, mainly focusing on the lepton family-violating processes. We present
an improved constraint in the polarized two-body muon decay and a set of new
bounds in tau decays. We also examine possible lepton family-violating signals
of the massless dark photon in future lepton colliders.
| [
{
"created": "Wed, 12 Apr 2023 06:47:10 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Jun 2023 05:45:23 GMT",
"version": "v2"
}
] | 2023-08-09 | [
[
"Deng",
"Xiaolong",
""
],
[
"Jaffredo",
"Florentin",
""
],
[
"Tanaka",
"Minoru",
""
]
] | We introduce a dark photon considering a U(1) gauge extension of the standard model in particle physics. Provided that the extra U(1) symmetry is unbroken, the dark photon is massless and has no coupling to the standard electromagnetic current. Higher-dimensional operators describe interactions of the massless dark photon with particles in the standard model. We investigate the interactions of the massless dark photon with charged leptons via dipole operators, mainly focusing on the lepton family-violating processes. We present an improved constraint in the polarized two-body muon decay and a set of new bounds in tau decays. We also examine possible lepton family-violating signals of the massless dark photon in future lepton colliders. |
hep-ph/9408344 | Xinnian Wang | Xin-Nian Wang, Miklos Gyulassy and Michael Pl\"umer | The LPM effect in QCD and Radiative energy loss in a quark-gluon plasma | 28 pages in REVTex, 4 figures in uuencoded files, LBL-35980 | Phys.Rev.D51:3436-3446,1995 | 10.1103/PhysRevD.51.3436 | null | hep-ph nucl-th | null | The non-abelian analog of the Landau-Pomeranchuk-Migdal effect is
investigated in perturbative QCD. Extending our previous studies, the
suppression of induced soft bremsstrahlung due to multiple scatterings of
quarks in the spinor representation is considered. The effective formation time
of gluon radiation due to the color interference is shown to depend on the
color representation of the emitting parton, and an improved formula for the
radiative energy loss is derived that interpolates between the factorization
and Bethe-Heitler limits.
| [
{
"created": "Mon, 22 Aug 1994 18:00:35 GMT",
"version": "v1"
}
] | 2009-10-09 | [
[
"Wang",
"Xin-Nian",
""
],
[
"Gyulassy",
"Miklos",
""
],
[
"Plümer",
"Michael",
""
]
] | The non-abelian analog of the Landau-Pomeranchuk-Migdal effect is investigated in perturbative QCD. Extending our previous studies, the suppression of induced soft bremsstrahlung due to multiple scatterings of quarks in the spinor representation is considered. The effective formation time of gluon radiation due to the color interference is shown to depend on the color representation of the emitting parton, and an improved formula for the radiative energy loss is derived that interpolates between the factorization and Bethe-Heitler limits. |
hep-ph/0601017 | Xiang Liu | Xiang Liu, Yan-Ming Yu, Shu-Min Zhao and Xue-Qian Li | Study on Decays of $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ in terms of the
CQM Model | 12 pages, 2 figures, 4 tables, a few references added | Eur.Phys.J.C47:445-452,2006 | 10.1140/epjc/s2006-02564-0 | null | hep-ph | null | Based on the assumption that $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ are the
$(0^+, 1^+)$ chiral partners of $D_{s}$ and $D^*_s$, we evaluate the strong
pionic and radiative decays of $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ in the
Constituent Quark Meson (CQM) model. Our numerical results of the relative
ratios of the decay widths are reasonably consistent with data.
| [
{
"created": "Tue, 3 Jan 2006 14:50:15 GMT",
"version": "v1"
},
{
"created": "Sat, 14 Jan 2006 15:10:42 GMT",
"version": "v2"
},
{
"created": "Fri, 27 Jan 2006 03:03:59 GMT",
"version": "v3"
}
] | 2009-01-07 | [
[
"Liu",
"Xiang",
""
],
[
"Yu",
"Yan-Ming",
""
],
[
"Zhao",
"Shu-Min",
""
],
[
"Li",
"Xue-Qian",
""
]
] | Based on the assumption that $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ are the $(0^+, 1^+)$ chiral partners of $D_{s}$ and $D^*_s$, we evaluate the strong pionic and radiative decays of $D_{sJ}^{*}(2317)$ and $D_{sJ}(2460)$ in the Constituent Quark Meson (CQM) model. Our numerical results of the relative ratios of the decay widths are reasonably consistent with data. |
hep-ph/0009140 | Gregory Moreau | G. Moreau | Single chargino production at linear colliders | 24 pages, Latex file. Linear Collider note LC-TH-2000-040 | null | null | T00/129 | hep-ph | null | We study the single chargino production $e^+ e^- \to \tilde \chi^{\pm}
\mu^{\mp}$ at linear colliders which occurs through the $\l_{121}$ R-parity
violating coupling constant. We focus on the final state containing 4 leptons
and some missing energy. The largest background is \susyq and can be reduced
using the initial beam polarization and some cuts based on the specific
kinematics of the single chargino production. Assuming the highest allowed
supersymmetric background, a center of mass energy of $\sqrt s=500GeV$ and a
luminosity of ${\cal L}=500fb^{-1}$, the sensitivities on the $\l_{121}$
coupling constant obtained from the single chargino production study improve
the low-energy experimental limit over a range of $\Delta m_{\tilde \nu}
\approx 500GeV$ around the sneutrino resonance, and reach values of $\sim
10^{-4}$ at the $\tilde \nu$ pole. The single chargino production also allows
to reconstruct the $\tilde \chi_1^{\pm}$, $\tilde \chi_2^{\pm}$ and $\tilde
\nu$ masses. The initial state radiation plays a fundamental role in this
study.
| [
{
"created": "Tue, 12 Sep 2000 11:18:49 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Moreau",
"G.",
""
]
] | We study the single chargino production $e^+ e^- \to \tilde \chi^{\pm} \mu^{\mp}$ at linear colliders which occurs through the $\l_{121}$ R-parity violating coupling constant. We focus on the final state containing 4 leptons and some missing energy. The largest background is \susyq and can be reduced using the initial beam polarization and some cuts based on the specific kinematics of the single chargino production. Assuming the highest allowed supersymmetric background, a center of mass energy of $\sqrt s=500GeV$ and a luminosity of ${\cal L}=500fb^{-1}$, the sensitivities on the $\l_{121}$ coupling constant obtained from the single chargino production study improve the low-energy experimental limit over a range of $\Delta m_{\tilde \nu} \approx 500GeV$ around the sneutrino resonance, and reach values of $\sim 10^{-4}$ at the $\tilde \nu$ pole. The single chargino production also allows to reconstruct the $\tilde \chi_1^{\pm}$, $\tilde \chi_2^{\pm}$ and $\tilde \nu$ masses. The initial state radiation plays a fundamental role in this study. |
hep-ph/0211436 | Gerasyuta S. M. | S.M. Gerasyuta, V.I. Kochkin | Relativistic quark model and pentaquark spectroscopy | 22 pages, pdf | Int.J.Mod.Phys. E12 (2003) 793-808 | 10.1142/S0218301303001582 | null | hep-ph | null | The relativistic five-quark equations are found in the framework of the
dispersion relation technique. The solutions of these equations using the
method based on the extraction of leading singularities of the amplitudes are
obtained. The five-quark amplitudes for the low-lying pentaquarks are
calculated under the condition that flavor SU(3) symmetry holds. The poles of
five-quark amplitudes determine the masses of the lowest pentaquarks. The mass
spectra of pentaquarks which contain only light quarks are calculated. The
calculation of pentaquark amplitudes estimates the contributions of three
subamplitudes. The main contributions to the pentaquark amplitude are
determined by the subamplitudes, which include the meson states.
| [
{
"created": "Wed, 27 Nov 2002 18:49:21 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Gerasyuta",
"S. M.",
""
],
[
"Kochkin",
"V. I.",
""
]
] | The relativistic five-quark equations are found in the framework of the dispersion relation technique. The solutions of these equations using the method based on the extraction of leading singularities of the amplitudes are obtained. The five-quark amplitudes for the low-lying pentaquarks are calculated under the condition that flavor SU(3) symmetry holds. The poles of five-quark amplitudes determine the masses of the lowest pentaquarks. The mass spectra of pentaquarks which contain only light quarks are calculated. The calculation of pentaquark amplitudes estimates the contributions of three subamplitudes. The main contributions to the pentaquark amplitude are determined by the subamplitudes, which include the meson states. |
1402.4735 | Daniel Whiteson | Pierre Baldi, Peter Sadowski, Daniel Whiteson | Searching for Exotic Particles in High-Energy Physics with Deep Learning | Accepted by Nature Communications. Added link to deep learning code | null | 10.1038/ncomms5308 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Collisions at high-energy particle colliders are a traditionally fruitful
source of exotic particle discoveries. Finding these rare particles requires
solving difficult signal-versus-background classification problems, hence
machine learning approaches are often used. Standard approaches have relied on
`shallow' machine learning models that have a limited capacity to learn complex
non-linear functions of the inputs, and rely on a pain-staking search through
manually constructed non-linear features. Progress on this problem has slowed,
as a variety of techniques have shown equivalent performance. Recent advances
in the field of deep learning make it possible to learn more complex functions
and better discriminate between signal and background classes. Using benchmark
datasets, we show that deep learning methods need no manually constructed
inputs and yet improve the classification metric by as much as 8\% over the
best current approaches. This demonstrates that deep learning approaches can
improve the power of collider searches for exotic particles.
| [
{
"created": "Wed, 19 Feb 2014 17:20:08 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Jun 2014 16:59:45 GMT",
"version": "v2"
}
] | 2015-06-18 | [
[
"Baldi",
"Pierre",
""
],
[
"Sadowski",
"Peter",
""
],
[
"Whiteson",
"Daniel",
""
]
] | Collisions at high-energy particle colliders are a traditionally fruitful source of exotic particle discoveries. Finding these rare particles requires solving difficult signal-versus-background classification problems, hence machine learning approaches are often used. Standard approaches have relied on `shallow' machine learning models that have a limited capacity to learn complex non-linear functions of the inputs, and rely on a pain-staking search through manually constructed non-linear features. Progress on this problem has slowed, as a variety of techniques have shown equivalent performance. Recent advances in the field of deep learning make it possible to learn more complex functions and better discriminate between signal and background classes. Using benchmark datasets, we show that deep learning methods need no manually constructed inputs and yet improve the classification metric by as much as 8\% over the best current approaches. This demonstrates that deep learning approaches can improve the power of collider searches for exotic particles. |
1105.2073 | Gordan Krnjaic | David E. Kaplan, Gordan Z. Krnjaic, Keith R. Rehermann, Christopher M.
Wells | Dark Atoms: Asymmetry and Direct Detection | 17 pages, 3 figures, expanded discussion of light degrees of freedom,
minor typos corrected, to appear in JCAP | null | 10.1088/1475-7516/2011/10/011 | null | hep-ph astro-ph.CO astro-ph.GA | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a simple UV completion of Atomic Dark Matter (aDM) in which heavy
right-handed neutrinos decay to induce both dark and lepton number densities.
This model addresses several outstanding cosmological problems: the
matter/anti-matter asymmetry, the dark matter abundance, the number of light
degrees of freedom in the early universe, and the smoothing of small-scale
structure. Additionally, this realization of aDM may reconcile the CoGeNT
excess with recently published null results and predicts a signal in the CRESST
Oxygen band. We also find that, due to unscreened long-range interactions, the
residual un recombined dark ions settle into a diffuse isothermal halo.
| [
{
"created": "Tue, 10 May 2011 23:24:50 GMT",
"version": "v1"
},
{
"created": "Tue, 7 Jun 2011 20:30:00 GMT",
"version": "v2"
},
{
"created": "Tue, 27 Sep 2011 00:47:45 GMT",
"version": "v3"
}
] | 2015-05-28 | [
[
"Kaplan",
"David E.",
""
],
[
"Krnjaic",
"Gordan Z.",
""
],
[
"Rehermann",
"Keith R.",
""
],
[
"Wells",
"Christopher M.",
""
]
] | We present a simple UV completion of Atomic Dark Matter (aDM) in which heavy right-handed neutrinos decay to induce both dark and lepton number densities. This model addresses several outstanding cosmological problems: the matter/anti-matter asymmetry, the dark matter abundance, the number of light degrees of freedom in the early universe, and the smoothing of small-scale structure. Additionally, this realization of aDM may reconcile the CoGeNT excess with recently published null results and predicts a signal in the CRESST Oxygen band. We also find that, due to unscreened long-range interactions, the residual un recombined dark ions settle into a diffuse isothermal halo. |
2012.02940 | Dian-Yong Chen | Qi Wu, Dian-Yong Chen, Takayuki Matsuki | $D$ wave bottomonia production from $Z_b^{(\prime)}$ decay | 9 pages, 5 figures, accepted for publication in the Phys.Rev.D | Phys. Rev. D 102, 114037 (2020) | 10.1103/PhysRevD.102.114037 | null | hep-ph | http://creativecommons.org/publicdomain/zero/1.0/ | In the present work, we investigate the dipion transitions between
$\Upsilon(5S)$ and $\Upsilon_J(1D)$ with $J=1, 2, 3$. Our analysis indicates
that the dominant sources of the anomalously large widths of $\Upsilon(5S)\to
\Upsilon_J(1D) \pi^+ \pi^-$ should be $Z_b^{(\prime)}$, i.e., the dipion
transitions occur via the cascade decays $\Upsilon(5S)\to Z_b^{(\prime)\pm}
\pi^\mp \to \Upsilon_J(1D) \pi^+ \pi^-$. With the assumption that all the short
ranged dynamics could be absorbed in a single cutoff with a model parameter
$\alpha$, the present estimations indicate that in a reasonable parameter range
the measured branching ratios of $\Upsilon(5S) \to \Upsilon_J(1D) \pi^+ \pi^-$
can be reproduced in magnitude, which further proves that the decays via
$Z_b^{(\prime)}$ dominate the dipion transitions of $\Upsilon(5S)$ to
$\Upsilon_J(1D)$. Moreover, we also predict the ratios of the branching
fractions of $Z_b^{(\prime)} \to \Upsilon_J(1D) \pi$, which in our calculations
are largely independent of the parameter $\alpha$ and could be tested by
further experiments in Belle II.
| [
{
"created": "Sat, 5 Dec 2020 03:34:50 GMT",
"version": "v1"
}
] | 2021-01-04 | [
[
"Wu",
"Qi",
""
],
[
"Chen",
"Dian-Yong",
""
],
[
"Matsuki",
"Takayuki",
""
]
] | In the present work, we investigate the dipion transitions between $\Upsilon(5S)$ and $\Upsilon_J(1D)$ with $J=1, 2, 3$. Our analysis indicates that the dominant sources of the anomalously large widths of $\Upsilon(5S)\to \Upsilon_J(1D) \pi^+ \pi^-$ should be $Z_b^{(\prime)}$, i.e., the dipion transitions occur via the cascade decays $\Upsilon(5S)\to Z_b^{(\prime)\pm} \pi^\mp \to \Upsilon_J(1D) \pi^+ \pi^-$. With the assumption that all the short ranged dynamics could be absorbed in a single cutoff with a model parameter $\alpha$, the present estimations indicate that in a reasonable parameter range the measured branching ratios of $\Upsilon(5S) \to \Upsilon_J(1D) \pi^+ \pi^-$ can be reproduced in magnitude, which further proves that the decays via $Z_b^{(\prime)}$ dominate the dipion transitions of $\Upsilon(5S)$ to $\Upsilon_J(1D)$. Moreover, we also predict the ratios of the branching fractions of $Z_b^{(\prime)} \to \Upsilon_J(1D) \pi$, which in our calculations are largely independent of the parameter $\alpha$ and could be tested by further experiments in Belle II. |
1606.02157 | Zhengliang Liang | Zheng-Liang Liang, Yue-Liang Wu, Zi-Qing Yang and Yu-Feng Zhou | On the evaporation of solar dark matter: spin-independent effective
operators | With optimised calculation of the solar dark matter, matches
published version | null | 10.1088/1475-7516/2016/09/018 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | As a part of the effort to investigate the implications of dark matter
(DM)-nucleon effective interactions on the solar DM detection, in this paper we
focus on the evaporation of the solar DM for a set of the DM-nucleon
spin-independent (SI) effective operators. In order to put the evaluation of
the evaporation rate on a more reliable ground, we calculate the non-thermal
distribution of the solar DM using the Monte Carlo methods, rather than
adopting the Maxwellian approximation. We then specify relevant signal
parameter spaces for the solar DM detection for various SI effective operators.
Based on the analysis, we determine the minimum DM masses for which the
DM-nucleon coupling strengths can be probed from the solar neutrino
observations. As an interesting application, our investigation also shows that
evaporation effect can not be neglectd in a recent proposal aiming to solve the
solar abundance problem by invoking the momentum-dependent asymmetric DM in the
Sun.
| [
{
"created": "Tue, 7 Jun 2016 14:44:20 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Jun 2016 13:28:32 GMT",
"version": "v2"
},
{
"created": "Sun, 18 Sep 2016 03:34:21 GMT",
"version": "v3"
}
] | 2016-09-20 | [
[
"Liang",
"Zheng-Liang",
""
],
[
"Wu",
"Yue-Liang",
""
],
[
"Yang",
"Zi-Qing",
""
],
[
"Zhou",
"Yu-Feng",
""
]
] | As a part of the effort to investigate the implications of dark matter (DM)-nucleon effective interactions on the solar DM detection, in this paper we focus on the evaporation of the solar DM for a set of the DM-nucleon spin-independent (SI) effective operators. In order to put the evaluation of the evaporation rate on a more reliable ground, we calculate the non-thermal distribution of the solar DM using the Monte Carlo methods, rather than adopting the Maxwellian approximation. We then specify relevant signal parameter spaces for the solar DM detection for various SI effective operators. Based on the analysis, we determine the minimum DM masses for which the DM-nucleon coupling strengths can be probed from the solar neutrino observations. As an interesting application, our investigation also shows that evaporation effect can not be neglectd in a recent proposal aiming to solve the solar abundance problem by invoking the momentum-dependent asymmetric DM in the Sun. |
hep-ph/9704437 | Carla Gobel Burlemaqui de Mello | Ignacio Bediaga, Carla Gobel and Ramon Mendez-Galain | A Phenomenological Analysis of Non-resonant Charm Meson Decays | 14 pages, Latex including 6 eps figures | Phys.Rev. D56 (1997) 4268-4273 | 10.1103/PhysRevD.56.4268 | null | hep-ph hep-ex | null | We analyse the consequences of the usual assumption of a constant function to
fit non-resonant decays from experimental Dalitz plot describing charmed meson
decays. We first show, using the $D^+\to \bar{K}^0\pi^+\pi^0$ decay channel as
an example, how an inadequate extraction of the non-resonant contribution could
yield incorrect measurements for the resonant channels. We analyse how the
correct study of this decay will provide a test for the validity of
factorization in D meson decays. Finally, we show how form factors could be
extracted from non-resonant decays. We particularly discuss about the form
factor that can be measured from the $D^+_s\to \pi^-\pi^+\pi^+$ decay. We
emphasize on its relevance for the study of the decay $\tau \to \nu_{\tau}
3\pi$ and the extraction of the $a_1$ meson width.
| [
{
"created": "Tue, 29 Apr 1997 13:18:00 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Bediaga",
"Ignacio",
""
],
[
"Gobel",
"Carla",
""
],
[
"Mendez-Galain",
"Ramon",
""
]
] | We analyse the consequences of the usual assumption of a constant function to fit non-resonant decays from experimental Dalitz plot describing charmed meson decays. We first show, using the $D^+\to \bar{K}^0\pi^+\pi^0$ decay channel as an example, how an inadequate extraction of the non-resonant contribution could yield incorrect measurements for the resonant channels. We analyse how the correct study of this decay will provide a test for the validity of factorization in D meson decays. Finally, we show how form factors could be extracted from non-resonant decays. We particularly discuss about the form factor that can be measured from the $D^+_s\to \pi^-\pi^+\pi^+$ decay. We emphasize on its relevance for the study of the decay $\tau \to \nu_{\tau} 3\pi$ and the extraction of the $a_1$ meson width. |
hep-ph/0002133 | Judith McGovern | K. B. Vijaya Kumar, Judith A. McGovern and Michael C. Birse | Spin polarisabilities of the nucleon at NLO in the chiral expansion | 8 pages, 2 figures, revtex. Minor typos corrected and reference added | Phys.Lett. B479 (2000) 167-172 | 10.1016/S0370-2693(00)00340-3 | MC/TH 00/01 | hep-ph nucl-th | null | We present a calculation of the fourth-order (NLO) contribution to
spin-dependent Compton scattering in heavy-baryon chiral perturbation theory,
and we give results for the four spin polarisabilities. No low-energy
constants, except for the anomalous magnetic moments of the nucleon, enter at
this order. For forward scattering the fourth-order piece of the spin
polarisability of the proton turns out to be almost twice the size of the
leading piece, with the opposite sign. This leads to the conclusion that no
prediction can currently be made for this quantity. For backward scattering the
fourth-order contribution is much smaller than the third-order piece which is
dominated by the anomalous scattering, and so cannot explain the discrepancy
between the CPT result and the current best experimental determination.
| [
{
"created": "Fri, 11 Feb 2000 19:16:39 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Mar 2000 14:21:55 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kumar",
"K. B. Vijaya",
""
],
[
"McGovern",
"Judith A.",
""
],
[
"Birse",
"Michael C.",
""
]
] | We present a calculation of the fourth-order (NLO) contribution to spin-dependent Compton scattering in heavy-baryon chiral perturbation theory, and we give results for the four spin polarisabilities. No low-energy constants, except for the anomalous magnetic moments of the nucleon, enter at this order. For forward scattering the fourth-order piece of the spin polarisability of the proton turns out to be almost twice the size of the leading piece, with the opposite sign. This leads to the conclusion that no prediction can currently be made for this quantity. For backward scattering the fourth-order contribution is much smaller than the third-order piece which is dominated by the anomalous scattering, and so cannot explain the discrepancy between the CPT result and the current best experimental determination. |
2312.11670 | Gonzalo Herrera | Motoko Fujiwara, Gonzalo Herrera | Tidal Disruption Events and Dark Matter Scatterings with Neutrinos and
Photons | Extended discussion on neutrino emission from TDEs; added references;
matches published version in Phys.Lett.B | Phys.Lett.B (2024) 138573 | 10.1016/j.physletb.2024.138573 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Stars can be tidally disrupted when passing near a black hole, and the debris
can induce a flux of high-energy neutrinos. It has been discussed that there
are hints in IceCube data of high-energy neutrinos produced in Tidal Disruption
Events. The emitting region of neutrinos and photons in these astrophysical
events is likely to be located in the vicinity of the central black hole, where
the dark matter density might be significantly larger than in the outer regions
of the galaxy. We explore the potential attenuation of the emitted neutrino and
photon fluxes due to interactions with dark matter particles around the
supermassive black hole of the host galaxies of AT2019dsg, AT2019fdr and
AT2019aalc, and study the implications for some well-motivated models of dark
matter-neutrino and dark matter-photon interactions. Furthermore, we discuss
the complementarity of our constraints with values of the dark matter-neutrino
scattering cross section proven to alleviate some cosmological tensions.
| [
{
"created": "Mon, 18 Dec 2023 19:26:58 GMT",
"version": "v1"
},
{
"created": "Sun, 17 Mar 2024 22:20:53 GMT",
"version": "v2"
}
] | 2024-03-19 | [
[
"Fujiwara",
"Motoko",
""
],
[
"Herrera",
"Gonzalo",
""
]
] | Stars can be tidally disrupted when passing near a black hole, and the debris can induce a flux of high-energy neutrinos. It has been discussed that there are hints in IceCube data of high-energy neutrinos produced in Tidal Disruption Events. The emitting region of neutrinos and photons in these astrophysical events is likely to be located in the vicinity of the central black hole, where the dark matter density might be significantly larger than in the outer regions of the galaxy. We explore the potential attenuation of the emitted neutrino and photon fluxes due to interactions with dark matter particles around the supermassive black hole of the host galaxies of AT2019dsg, AT2019fdr and AT2019aalc, and study the implications for some well-motivated models of dark matter-neutrino and dark matter-photon interactions. Furthermore, we discuss the complementarity of our constraints with values of the dark matter-neutrino scattering cross section proven to alleviate some cosmological tensions. |
hep-ph/0603014 | Sannino Francesco | Sven Bjarke Gudnason, Chris Kouvaris, and Francesco Sannino (Bohr
Institute) | Towards Working Technicolor: Effective Theories and Dark Matter | RevTeX, 17 pages, 2 figures. V2: more precise explanation of formula
(33) | Phys.Rev. D73 (2006) 115003 | 10.1103/PhysRevD.73.115003 | null | hep-ph | null | A fifth force, of technicolor type, responsible for breaking the electroweak
theory is an intriguing extension of the Standard Model. Recently new theories
have been shown to feature walking dynamics for a very low number of
techniflavors and are not ruled out by electroweak precision measurements. We
identify the light degrees of freedom and construct the associated low energy
effective theories. These can be used to study signatures and relevant
processes in current and future experiments. In our theory the technibaryons
are pseudo Goldstone bosons and their masses arise via extended technicolor
interactions. There are hypercharge assignments for the techniquarks which
renders one of the technibaryons electrically neutral. We investigate the
cosmological implications of this scenario and provide a component of dark
matter.
| [
{
"created": "Thu, 2 Mar 2006 15:42:53 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Oct 2006 23:41:39 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Gudnason",
"Sven Bjarke",
"",
"Bohr\n Institute"
],
[
"Kouvaris",
"Chris",
"",
"Bohr\n Institute"
],
[
"Sannino",
"Francesco",
"",
"Bohr\n Institute"
]
] | A fifth force, of technicolor type, responsible for breaking the electroweak theory is an intriguing extension of the Standard Model. Recently new theories have been shown to feature walking dynamics for a very low number of techniflavors and are not ruled out by electroweak precision measurements. We identify the light degrees of freedom and construct the associated low energy effective theories. These can be used to study signatures and relevant processes in current and future experiments. In our theory the technibaryons are pseudo Goldstone bosons and their masses arise via extended technicolor interactions. There are hypercharge assignments for the techniquarks which renders one of the technibaryons electrically neutral. We investigate the cosmological implications of this scenario and provide a component of dark matter. |
2001.00698 | Yuta Kikuchi | Dmitri E. Kharzeev and Yuta Kikuchi | Real-time chiral dynamics from a digital quantum simulation | 13 pages, 6 figures; version accepted for Physical Review Research | Phys. Rev. Research 2, 023342 (2020) | 10.1103/PhysRevResearch.2.023342 | RBRC-1321 | hep-ph hep-lat quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The chiral magnetic effect in a strong magnetic field can be described using
the chiral anomaly in the $(1+1)$-dimensional massive Schwinger model with a
time-dependent $\theta$-term. We perform a digital quantum simulation of the
model at finite $\theta$-angle and vanishing gauge coupling using an IBM-Q
digital quantum simulator, and observe the corresponding vector current induced
in a system of relativistic fermions by a global {\it chiral quench} -- a
sudden change in the chiral chemical potential or $\theta$-angle. At finite
fermion mass, there appears an additional contribution to this current that
stems from the non-anomalous relaxation of chirality. Our results are relevant
for the real-time dynamics of chiral magnetic effect in heavy ion collisions
and in chiral materials, as well as for modeling high-energy processes at
hadron colliders.
| [
{
"created": "Fri, 3 Jan 2020 02:34:31 GMT",
"version": "v1"
},
{
"created": "Fri, 24 Jan 2020 17:45:03 GMT",
"version": "v2"
},
{
"created": "Fri, 15 May 2020 19:30:07 GMT",
"version": "v3"
},
{
"created": "Tue, 16 Jun 2020 15:26:10 GMT",
"version": "v4"
}
] | 2020-07-01 | [
[
"Kharzeev",
"Dmitri E.",
""
],
[
"Kikuchi",
"Yuta",
""
]
] | The chiral magnetic effect in a strong magnetic field can be described using the chiral anomaly in the $(1+1)$-dimensional massive Schwinger model with a time-dependent $\theta$-term. We perform a digital quantum simulation of the model at finite $\theta$-angle and vanishing gauge coupling using an IBM-Q digital quantum simulator, and observe the corresponding vector current induced in a system of relativistic fermions by a global {\it chiral quench} -- a sudden change in the chiral chemical potential or $\theta$-angle. At finite fermion mass, there appears an additional contribution to this current that stems from the non-anomalous relaxation of chirality. Our results are relevant for the real-time dynamics of chiral magnetic effect in heavy ion collisions and in chiral materials, as well as for modeling high-energy processes at hadron colliders. |
1409.7791 | Norma Susana Mankoc Borstnik | Norma Susana Mankoc Borstnik | Can the spin-charge-family theory explain baryon number non
conservation? | 48 pages, in press in Phys. Rev. D, modified version of the talk in
the Proceedings to the $17^th$ Workshop "What comes beyond the standard
models", Bled, 20-28 of July, 2014 | Phys. Rev. D 91, 065004 (2015) | 10.1103/PhysRevD.91.065004 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The spin-charge-family theory, in which spinors carry besides the Dirac spin
also the second kind of the Clifford object, no charges, is a kind of the
Kaluza-Klein theories. The Dirac spinors of one Weyl representation in
$d=(13+1)$ manifest in $d=(3+1)$ at low energies all the properties of quarks
and leptons assumed by the standard model. The second kind of spins explains
the origin of families. Spinors interact with the vielbeins and the two kinds
of the spin connection fields, the gauge fields of the two kinds of the
Clifford objects, which manifest in $d=(3+1)$ besides the gravity and the known
gauge vector fields also several scalar gauge fields. Scalars with the space
index $s\in (7,8)$ carry the weak charge and the hyper charge ($\mp
\frac{1}{2}, \pm \frac{1}{2}$, respectively), explaining the origin of the
Higgs and the Yukawa couplings. It is demonstrated in this paper that the
scalar fields with the space index $t\in (9,10,\dots,14)$ carry the triplet
colour charges, causing transitions of antileptons and antiquarks into quarks
and back, enabling the appearance and the decay of baryons. These scalar fields
are offering in the presence of the right handed neutrino condensate, which
breaks the ${\cal C}{\cal P}$ symmetry, the answer to the question about the
matter-antimatter asymmetry.
| [
{
"created": "Sat, 27 Sep 2014 10:39:19 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Dec 2014 11:25:52 GMT",
"version": "v2"
},
{
"created": "Tue, 24 Feb 2015 14:17:49 GMT",
"version": "v3"
}
] | 2015-03-11 | [
[
"Borstnik",
"Norma Susana Mankoc",
""
]
] | The spin-charge-family theory, in which spinors carry besides the Dirac spin also the second kind of the Clifford object, no charges, is a kind of the Kaluza-Klein theories. The Dirac spinors of one Weyl representation in $d=(13+1)$ manifest in $d=(3+1)$ at low energies all the properties of quarks and leptons assumed by the standard model. The second kind of spins explains the origin of families. Spinors interact with the vielbeins and the two kinds of the spin connection fields, the gauge fields of the two kinds of the Clifford objects, which manifest in $d=(3+1)$ besides the gravity and the known gauge vector fields also several scalar gauge fields. Scalars with the space index $s\in (7,8)$ carry the weak charge and the hyper charge ($\mp \frac{1}{2}, \pm \frac{1}{2}$, respectively), explaining the origin of the Higgs and the Yukawa couplings. It is demonstrated in this paper that the scalar fields with the space index $t\in (9,10,\dots,14)$ carry the triplet colour charges, causing transitions of antileptons and antiquarks into quarks and back, enabling the appearance and the decay of baryons. These scalar fields are offering in the presence of the right handed neutrino condensate, which breaks the ${\cal C}{\cal P}$ symmetry, the answer to the question about the matter-antimatter asymmetry. |
0712.1901 | Dimiter Stamenov | Elliot Leader, Alexander V. Sidorov, Dimiter B. Stamenov | Progress in the Determination of Polarized PDFs and Higher Twist | 9 pages, 7 figures, to appear in the Proceedings of 12th Workshop on
High Energy Spin Physics (DSPIN'07), Dubna, Russia, 3-7 Sept, 2007 | null | null | null | hep-ph hep-ex | null | The impact of the recent very precise CLAS and COMPASS g1/F1 data on
polarized parton densities and higher twist effects is discussed. It is
demonstrated that the low Q^2 CLAS data improve essentially our knowledge of
higher twist corrections to the spin structure function g1, while the large Q^2
COMPASS data influence mainly the strange quark and gluon polarizations. It is
also shown that the uncertainties in the determination of the polarized parton
densities are significantly reduced. We find also that the present inclusive
DIS data cannot rule out a negative polarized and changing in sign gluon
densities. The present status of the proton spin sum rule is discussed.
| [
{
"created": "Wed, 12 Dec 2007 10:38:57 GMT",
"version": "v1"
}
] | 2007-12-13 | [
[
"Leader",
"Elliot",
""
],
[
"Sidorov",
"Alexander V.",
""
],
[
"Stamenov",
"Dimiter B.",
""
]
] | The impact of the recent very precise CLAS and COMPASS g1/F1 data on polarized parton densities and higher twist effects is discussed. It is demonstrated that the low Q^2 CLAS data improve essentially our knowledge of higher twist corrections to the spin structure function g1, while the large Q^2 COMPASS data influence mainly the strange quark and gluon polarizations. It is also shown that the uncertainties in the determination of the polarized parton densities are significantly reduced. We find also that the present inclusive DIS data cannot rule out a negative polarized and changing in sign gluon densities. The present status of the proton spin sum rule is discussed. |
2407.01672 | Matthew Low | Kun Cheng, Tao Han, Matthew Low | Optimizing Entanglement and Bell Inequality Violation in Top Anti-Top
Events | 49 pages, 11 figures, 1 table | null | null | PITT-PACC-2401 | hep-ph hep-th quant-ph | http://creativecommons.org/licenses/by/4.0/ | A top quark and an anti-top quark produced together at colliders have
correlated spins. These spins constitute a quantum state that can exhibit
entanglement and violate Bell's inequality. In realistic collider experiments,
most analyses allow the axes, as well the Lorentz frame to vary event-by-event,
thus introducing a dependence on the choice of event-dependent basis leading us
to adopt "fictitious states," rather than genuine quantum states. The basis
dependence of fictitious states allows for an optimization procedure, which
makes the usage of fictitious states advantageous in measuring entanglement and
Bell inequality violation. In this work, we show analytically that the basis
which diagonalizes the spin-spin correlations is optimal for maximizing spin
correlations, entanglement, and Bell inequality violation. We show that the
optimal basis is approximately the same as the fixed beam basis (or the rotated
beam basis) near the $t\bar t$ production threshold, while it approaches the
helicity basis far above threshold. Using this basis, we present the
sensitivity for entanglement and Bell inequality violation in $t\bar t$ events
at the LHC and a future $e^+e^-$ collider. Since observing Bell inequality
violation appears to be quite challenging experimentally, and requires a large
dataset in collider experiments, choosing the optimal basis is crucially
important to observe Bell inequality violation. Our method and general approach
are equally applicable to other systems beyond $t \bar t$, including
interactions beyond the Standard Model.
| [
{
"created": "Mon, 1 Jul 2024 18:00:01 GMT",
"version": "v1"
}
] | 2024-07-03 | [
[
"Cheng",
"Kun",
""
],
[
"Han",
"Tao",
""
],
[
"Low",
"Matthew",
""
]
] | A top quark and an anti-top quark produced together at colliders have correlated spins. These spins constitute a quantum state that can exhibit entanglement and violate Bell's inequality. In realistic collider experiments, most analyses allow the axes, as well the Lorentz frame to vary event-by-event, thus introducing a dependence on the choice of event-dependent basis leading us to adopt "fictitious states," rather than genuine quantum states. The basis dependence of fictitious states allows for an optimization procedure, which makes the usage of fictitious states advantageous in measuring entanglement and Bell inequality violation. In this work, we show analytically that the basis which diagonalizes the spin-spin correlations is optimal for maximizing spin correlations, entanglement, and Bell inequality violation. We show that the optimal basis is approximately the same as the fixed beam basis (or the rotated beam basis) near the $t\bar t$ production threshold, while it approaches the helicity basis far above threshold. Using this basis, we present the sensitivity for entanglement and Bell inequality violation in $t\bar t$ events at the LHC and a future $e^+e^-$ collider. Since observing Bell inequality violation appears to be quite challenging experimentally, and requires a large dataset in collider experiments, choosing the optimal basis is crucially important to observe Bell inequality violation. Our method and general approach are equally applicable to other systems beyond $t \bar t$, including interactions beyond the Standard Model. |
1904.13174 | Claudio Coriano | Claudio Corian\`o, Matteo Maria Maglio, Alessandro Tatullo,
Dimosthenis Theofilopoulos | Exact Correlators from Conformal Ward Identities in Momentum Space and
Perturbative Realizations | 48 pages, 12 figures, (typos corrected) Proceedings of the Corfu
Summer Institute 2018 "School and Workshops on Elementary Particle Physics
and Gravity" 1-27 September 2018 Corfu, Greece | null | null | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The general solution of the conformal Ward identities (CWI's) in momentum
space, and their matching to perturbation theory, allows to uncover some
specific characteristics of the breaking of conformal symmetry, induced by the
anomaly. It allows to compare perturbative features of the 1-particle
irreducible (1PI, nonlocal) anomaly action with the prediction of a similar
(but exact) nonlocal action identified by the CWI's. The two predictions can be
exactly matched at the level of 3-point functions. The analysis of the $TJJ$
and $TTT$ shows that both approaches - based either on 1PI or on the exact
solutions of the CWI's - predict massless (dynamical) scalar exchanges in
3-point functions as the signature of the conformal anomaly. In a local
formulation such 1PI actions exhibit a ghost in the spectrum which may induce
ghost condensation. We also discuss alternative approaches, which take to
Wess-Zumino forms of the action with an asymptotic dilaton, which should be
considered phenomenological alternatives to the exact nonlocal action. If
derived by a Weyl gauging, they also include a ghost in the spectrum. The two
formulations, nonlocal and of WZ type, can be unified under the assumption that
they describe the same anomaly phenomenon at two separate (UV/IR) ends of the
renormalization group flow, possibly separated by a vacuum rearrangement at an
intermediate scale. A similar analysis is presented for an $\mathcal{N}=1$
supersymmetric Yang-Mills theory. We comment on the possibile cosmological
implications of such quasi Nambu-Goldstone modes as ultralight dilatons and
axions.
| [
{
"created": "Tue, 30 Apr 2019 11:44:21 GMT",
"version": "v1"
},
{
"created": "Wed, 15 May 2019 08:31:57 GMT",
"version": "v2"
},
{
"created": "Thu, 16 May 2019 17:50:07 GMT",
"version": "v3"
}
] | 2019-05-17 | [
[
"Corianò",
"Claudio",
""
],
[
"Maglio",
"Matteo Maria",
""
],
[
"Tatullo",
"Alessandro",
""
],
[
"Theofilopoulos",
"Dimosthenis",
""
]
] | The general solution of the conformal Ward identities (CWI's) in momentum space, and their matching to perturbation theory, allows to uncover some specific characteristics of the breaking of conformal symmetry, induced by the anomaly. It allows to compare perturbative features of the 1-particle irreducible (1PI, nonlocal) anomaly action with the prediction of a similar (but exact) nonlocal action identified by the CWI's. The two predictions can be exactly matched at the level of 3-point functions. The analysis of the $TJJ$ and $TTT$ shows that both approaches - based either on 1PI or on the exact solutions of the CWI's - predict massless (dynamical) scalar exchanges in 3-point functions as the signature of the conformal anomaly. In a local formulation such 1PI actions exhibit a ghost in the spectrum which may induce ghost condensation. We also discuss alternative approaches, which take to Wess-Zumino forms of the action with an asymptotic dilaton, which should be considered phenomenological alternatives to the exact nonlocal action. If derived by a Weyl gauging, they also include a ghost in the spectrum. The two formulations, nonlocal and of WZ type, can be unified under the assumption that they describe the same anomaly phenomenon at two separate (UV/IR) ends of the renormalization group flow, possibly separated by a vacuum rearrangement at an intermediate scale. A similar analysis is presented for an $\mathcal{N}=1$ supersymmetric Yang-Mills theory. We comment on the possibile cosmological implications of such quasi Nambu-Goldstone modes as ultralight dilatons and axions. |
1007.4313 | Levon Grigoryan | L. Grigoryan | Average formation lengths of baryons and antibaryons in string model | 7 pages, 6 figures | Phys.Rev.C83:014904,2011 | 10.1103/PhysRevC.83.014904 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work it is continued the investigation of the space-time scales of
the hadronization process in the framework of string model. The average
formation lengths of several widely using species of baryons (antibaryons) such
as $p$ ($\bar{p}$), $n$ ($\bar{n}$), $\Delta$ ($\bar{\Delta}$), $\Lambda$
($\bar{\Lambda}$) and $\Sigma$ ($\bar{\Sigma}$) are studied. It is shown that
they depend from electrical charges or, more precise, from quark contents of
the hadrons. In particular, the average formation lengths of positively charged
hadrons, for example protons, are considerably larger than of their negatively
charged antiparticles, antiprotons. This statement is fulfilled for all nuclear
targets and any value of the Bjorken scaling variable $x_{Bj}$. The main
mechanism is direct production. Additional production mechanism in result of
decay of resonances gives small contribution. It is shown that the average
formation lengths of protons (antiprotons) are slowly rising (decreasing)
functions of $x_{Bj}$, the ones of neutrons and antineutrons are slowly
decreasing functions of $x_{Bj}$. The shape and behavior of average formation
lengths for baryons qualitatively coincide with the ones for pseudoscalar
mesons obtained earlier.
| [
{
"created": "Sun, 25 Jul 2010 09:47:29 GMT",
"version": "v1"
}
] | 2011-01-28 | [
[
"Grigoryan",
"L.",
""
]
] | In this work it is continued the investigation of the space-time scales of the hadronization process in the framework of string model. The average formation lengths of several widely using species of baryons (antibaryons) such as $p$ ($\bar{p}$), $n$ ($\bar{n}$), $\Delta$ ($\bar{\Delta}$), $\Lambda$ ($\bar{\Lambda}$) and $\Sigma$ ($\bar{\Sigma}$) are studied. It is shown that they depend from electrical charges or, more precise, from quark contents of the hadrons. In particular, the average formation lengths of positively charged hadrons, for example protons, are considerably larger than of their negatively charged antiparticles, antiprotons. This statement is fulfilled for all nuclear targets and any value of the Bjorken scaling variable $x_{Bj}$. The main mechanism is direct production. Additional production mechanism in result of decay of resonances gives small contribution. It is shown that the average formation lengths of protons (antiprotons) are slowly rising (decreasing) functions of $x_{Bj}$, the ones of neutrons and antineutrons are slowly decreasing functions of $x_{Bj}$. The shape and behavior of average formation lengths for baryons qualitatively coincide with the ones for pseudoscalar mesons obtained earlier. |
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