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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1112.3461 | Giorgia Fugallo | Walter Tarantino | Dark Matter and Dark Energy via Non-Perturbative (Flavour) Vacua | 14 pages, 2 figures | Phys. Rev. D 85, 045020 (2012) | 10.1103/PhysRevD.85.045020 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A non-perturbative field theoretical approach to flavour physics
(Blasone-Vitiello formalism) has been shown to imply a highly non-trivial
vacuum state. In a previous work, we implemented the approach on a simple
supersymmetric model (free Wess-Zumino), with flavour mixing, which was
regarded as a model for free neutrinos and sneutrinos. The resulting effective
vacuum (called "flavour vacuum") was found to be characterized by a strong SUSY
breaking. In this paper we explore the phenomenology of the model and we argue
that the flavour vacuum is a consistent source for both Dark Energy (thanks to
the bosonic sector of the model) and Dark Matter (via the fermionic one). Quite
remarkably, besides the parameters connected with neutrino physics, in this
model no other parameters have been introduced, possibly leading to a
predictive theory of Dark Energy/Matter. Despite its oversimplification, such a
toy model already seems capable to shed some light on the observed energy
hierarchy between neutrino physics, Dark Energy and Dark Matter. Furthermore,
we move a step forth in the construction of a more realistic theory, by
presenting a novel approach for calculating relevant quantities and hence
extending some results to interactive theories, in a completely
non-perturbative way.
| [
{
"created": "Thu, 15 Dec 2011 09:43:22 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Jan 2012 22:29:03 GMT",
"version": "v2"
}
] | 2012-02-20 | [
[
"Tarantino",
"Walter",
""
]
] | A non-perturbative field theoretical approach to flavour physics (Blasone-Vitiello formalism) has been shown to imply a highly non-trivial vacuum state. In a previous work, we implemented the approach on a simple supersymmetric model (free Wess-Zumino), with flavour mixing, which was regarded as a model for free neutrinos and sneutrinos. The resulting effective vacuum (called "flavour vacuum") was found to be characterized by a strong SUSY breaking. In this paper we explore the phenomenology of the model and we argue that the flavour vacuum is a consistent source for both Dark Energy (thanks to the bosonic sector of the model) and Dark Matter (via the fermionic one). Quite remarkably, besides the parameters connected with neutrino physics, in this model no other parameters have been introduced, possibly leading to a predictive theory of Dark Energy/Matter. Despite its oversimplification, such a toy model already seems capable to shed some light on the observed energy hierarchy between neutrino physics, Dark Energy and Dark Matter. Furthermore, we move a step forth in the construction of a more realistic theory, by presenting a novel approach for calculating relevant quantities and hence extending some results to interactive theories, in a completely non-perturbative way. |
hep-ph/9512266 | Alick MacPherson | Alick L. Macpherson | Nucleon Decay in Non-Minimal Supersymmetric SO(10) | 21 pages, uuencoded LaTeX file and 5 postscript figures | Nucl.Phys. B472 (1996) 79-94 | 10.1016/0550-3213(96)00220-9 | Alberta-Thy-28-95 | hep-ph | null | Evaluation of nucleon decay modes and branching ratios in a non-minimal
supersymmetric SO(10) grand unified theory is presented. The non-minimal GUT
considered is the supersymmetrised version of the `realistic' SO(10) model
originally proposed by Harvey, Reiss, and Ramond, which is realistic in that it
gives acceptable charged fermion and neutrino masses within the context of a
phenomenological fit to the low energy standard model inputs. Despite a
complicated Higgs sector, the SO(10) $\underline{10}$ Higgs superfield mass
insertion is found to be the sole contribution to the tree level F-term
governing nucleon decay. The resulting dimension 5 operators that mediate
nucleon decay give branching ratio predictions parameterised by a single
parameter, the ratio of the Yukawa couplings of the $\underline{10}$ to the
fermion generations. For parameter values corresponding to a lack of dominance
of the third family self coupling, the dominant nucleon decay modes are $p
\rightarrow K^{+} + \bar{\nu}_{\mu}$ and $n \rightarrow K^{0} +
\bar{\nu}_{\mu}$, as expected. Further, the charged muon decay modes are
enhanced by two orders of magnitude over the standard minimal SUSY SU(5)
predictions, thus predicting a distinct spectrum of `visible' modes. These
charged muon decay modes, along with $p \rightarrow \pi^{+} + \bar{\nu}_{\mu}$
and $n \rightarrow \pi^{0} + \bar{\nu}_{\mu}$, which are moderately enhanced
over the SUSY SU(5) prediction, suggest a distinguishing fingerprint of this
particular GUT model, and if nucleon decay is observed at Super-KAMIOKANDE the
predicted branching ratio spectrum can be used to determine the validity of
this `realistic' SO(10) SUSY GUT model.
| [
{
"created": "Sun, 10 Dec 1995 22:52:55 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Macpherson",
"Alick L.",
""
]
] | Evaluation of nucleon decay modes and branching ratios in a non-minimal supersymmetric SO(10) grand unified theory is presented. The non-minimal GUT considered is the supersymmetrised version of the `realistic' SO(10) model originally proposed by Harvey, Reiss, and Ramond, which is realistic in that it gives acceptable charged fermion and neutrino masses within the context of a phenomenological fit to the low energy standard model inputs. Despite a complicated Higgs sector, the SO(10) $\underline{10}$ Higgs superfield mass insertion is found to be the sole contribution to the tree level F-term governing nucleon decay. The resulting dimension 5 operators that mediate nucleon decay give branching ratio predictions parameterised by a single parameter, the ratio of the Yukawa couplings of the $\underline{10}$ to the fermion generations. For parameter values corresponding to a lack of dominance of the third family self coupling, the dominant nucleon decay modes are $p \rightarrow K^{+} + \bar{\nu}_{\mu}$ and $n \rightarrow K^{0} + \bar{\nu}_{\mu}$, as expected. Further, the charged muon decay modes are enhanced by two orders of magnitude over the standard minimal SUSY SU(5) predictions, thus predicting a distinct spectrum of `visible' modes. These charged muon decay modes, along with $p \rightarrow \pi^{+} + \bar{\nu}_{\mu}$ and $n \rightarrow \pi^{0} + \bar{\nu}_{\mu}$, which are moderately enhanced over the SUSY SU(5) prediction, suggest a distinguishing fingerprint of this particular GUT model, and if nucleon decay is observed at Super-KAMIOKANDE the predicted branching ratio spectrum can be used to determine the validity of this `realistic' SO(10) SUSY GUT model. |
hep-ph/0310141 | Sergio Morais Lietti | O. J. P. Eboli, M.C. Gonzalez-Garcia, S. M. Lietti | Bosonic Quartic Couplings at LHC | 18 pages, 2 figures, revised version | Phys.Rev.D69:095005,2004 | 10.1103/PhysRevD.69.095005 | null | hep-ph | null | We analyze the potential of the CERN Large Hadron Collider (LHC) to study
anomalous quartic vector-boson interactions Z Z gamma gamma, Z Z Z gamma, W+ W-
gamma gamma, and W+ W- Z gamma through the weak boson fusion processes q q -> q
q gamma gamma and q q -> q q gamma Z(-> l+ l-) with l = electron or muon. After
a careful study of the backgrounds and how to extract them from the data, we
show that the process p p -> j j gamma l+ l- is potentially the most sensitive
to deviations from the Standard Model, improving the sensitivity to anomalous
couplings by up to a factor 10^4 (10^2) with respect to the present direct
(indirect) limits.
| [
{
"created": "Fri, 10 Oct 2003 20:08:14 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Dec 2003 14:21:27 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Eboli",
"O. J. P.",
""
],
[
"Gonzalez-Garcia",
"M. C.",
""
],
[
"Lietti",
"S. M.",
""
]
] | We analyze the potential of the CERN Large Hadron Collider (LHC) to study anomalous quartic vector-boson interactions Z Z gamma gamma, Z Z Z gamma, W+ W- gamma gamma, and W+ W- Z gamma through the weak boson fusion processes q q -> q q gamma gamma and q q -> q q gamma Z(-> l+ l-) with l = electron or muon. After a careful study of the backgrounds and how to extract them from the data, we show that the process p p -> j j gamma l+ l- is potentially the most sensitive to deviations from the Standard Model, improving the sensitivity to anomalous couplings by up to a factor 10^4 (10^2) with respect to the present direct (indirect) limits. |
hep-ph/0610408 | Grzegorz Wilk | Oleg Utyuzh, Grzegorz Wilk and Zbigniew Wlodarczyk | Numerical symmetrization of state of identical particles | Talk presented by O.Utyuzh at XXXVI International Symposium on
Multiparticle Dynamics, September 2-8, 2006, Paraty (RJ), Brazil; minor
corrections, to be published in Braz. J. Phys. (2007) | Braz.J.Phys.37:708-710,2007 | null | null | hep-ph nucl-th | null | The method of numerical symmetrization of state of identical particles
proposed by us before is clarified and discussed.
| [
{
"created": "Mon, 30 Oct 2006 14:09:54 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Dec 2006 10:15:01 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Utyuzh",
"Oleg",
""
],
[
"Wilk",
"Grzegorz",
""
],
[
"Wlodarczyk",
"Zbigniew",
""
]
] | The method of numerical symmetrization of state of identical particles proposed by us before is clarified and discussed. |
2010.03871 | Alina Golub | Alina Golub, Selym Villalba-Ch\'avez, Hartmut Ruhl, Carsten M\"uller | Linear Breit-Wheeler pair production by high-energy bremsstrahlung
photons colliding with an intense X-ray laser pulse | 8 pages, 5 figures | Phys. Rev. D 103, 016009 (2021) | 10.1103/PhysRevD.103.016009 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A possible setup for the experimental verification of linear Breit-Wheeler
pair creation of electrons and positrons in photon-photon collisions is studied
theoretically. It combines highly energetic bremsstrahlung photons, which are
assumed to be generated by an incident beam of GeV electrons penetrating
through a high-$Z$ target, with keV photons from an X-ray laser field, which is
described as a focused Gaussian pulse. We discuss the dependencies of the pair
yields on the incident electron energy, target thickness, laser parameters, and
collision geometry. It is shown that, for suitable conditions which are
nowadays in reach at X-ray laser facilities, the resulting number of created
particles seems to be well accessible for enabling the first experimental
observation of the linear Breit-Wheeler process $\gamma\gamma\to e^+e^-$.
| [
{
"created": "Thu, 8 Oct 2020 09:54:43 GMT",
"version": "v1"
}
] | 2021-01-20 | [
[
"Golub",
"Alina",
""
],
[
"Villalba-Chávez",
"Selym",
""
],
[
"Ruhl",
"Hartmut",
""
],
[
"Müller",
"Carsten",
""
]
] | A possible setup for the experimental verification of linear Breit-Wheeler pair creation of electrons and positrons in photon-photon collisions is studied theoretically. It combines highly energetic bremsstrahlung photons, which are assumed to be generated by an incident beam of GeV electrons penetrating through a high-$Z$ target, with keV photons from an X-ray laser field, which is described as a focused Gaussian pulse. We discuss the dependencies of the pair yields on the incident electron energy, target thickness, laser parameters, and collision geometry. It is shown that, for suitable conditions which are nowadays in reach at X-ray laser facilities, the resulting number of created particles seems to be well accessible for enabling the first experimental observation of the linear Breit-Wheeler process $\gamma\gamma\to e^+e^-$. |
hep-ph/9411278 | Department of Theoretical Physics | A.A.Gvozdev, A.V.Kuznetsov, N.V.Mikheev and L.A.Vassilevskaya | Muon decays with lepton--number violation via vector leptoquark | 10 pages, LaTeX, Submitted to Phys.Lett.B | Phys.Lett. B345 (1995) 490-494 | 10.1016/0370-2693(95)00003-4 | YARU-HE-94/09 (Yaroslavl State University) | hep-ph | null | The decays $\mu \rightarrow e \gamma$, $\mu \rightarrow e \gamma \gamma$, and
$\mu \rightarrow e e \bar e$ are analysed in the framework of the Pati-Salam
type quark-lepton symmetry $SU(4)_V \otimes SU(2)_L \otimes G_R$ where the
effects of mixing in the quark-lepton currents are taken into account. It is
shown that the $\mu \rightarrow e \gamma \gamma$ and $\mu \rightarrow e e \bar
e$ decays via the vector leptoquark have not a GIM--type suppression, while the
$\mu \rightarrow e \gamma$ decay has. So, the specific hierarchy of the decay
probabilities could take place $\Gamma(\mu \rightarrow e e \bar e) \gg
\Gamma(\mu \rightarrow e \gamma \gamma) \gg \Gamma(\mu \rightarrow e \gamma)$.
The existing bounds on the vector leptoquark mass and on the mixing matrix
elements, based on the data for the $\mu e$ conversion in nuclei and for the
ratio of the $K_{e 2}$ and $K_{\mu 2}$ decays allow to set the upper limits on
the branching ratios at a level of $10^{-18}$ for the $\mu \rightarrow e \gamma
\gamma$ decay and at a level of $10^{-15}$ for the $\mu \rightarrow e e \bar e$
decay.
| [
{
"created": "Sat, 12 Nov 1994 13:21:52 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Nov 1994 13:54:53 GMT",
"version": "v2"
}
] | 2009-10-28 | [
[
"Gvozdev",
"A. A.",
""
],
[
"Kuznetsov",
"A. V.",
""
],
[
"Mikheev",
"N. V.",
""
],
[
"Vassilevskaya",
"L. A.",
""
]
] | The decays $\mu \rightarrow e \gamma$, $\mu \rightarrow e \gamma \gamma$, and $\mu \rightarrow e e \bar e$ are analysed in the framework of the Pati-Salam type quark-lepton symmetry $SU(4)_V \otimes SU(2)_L \otimes G_R$ where the effects of mixing in the quark-lepton currents are taken into account. It is shown that the $\mu \rightarrow e \gamma \gamma$ and $\mu \rightarrow e e \bar e$ decays via the vector leptoquark have not a GIM--type suppression, while the $\mu \rightarrow e \gamma$ decay has. So, the specific hierarchy of the decay probabilities could take place $\Gamma(\mu \rightarrow e e \bar e) \gg \Gamma(\mu \rightarrow e \gamma \gamma) \gg \Gamma(\mu \rightarrow e \gamma)$. The existing bounds on the vector leptoquark mass and on the mixing matrix elements, based on the data for the $\mu e$ conversion in nuclei and for the ratio of the $K_{e 2}$ and $K_{\mu 2}$ decays allow to set the upper limits on the branching ratios at a level of $10^{-18}$ for the $\mu \rightarrow e \gamma \gamma$ decay and at a level of $10^{-15}$ for the $\mu \rightarrow e e \bar e$ decay. |
0808.2888 | Patel Bhavin Mr. | Bhavin Patel and P.C.Vinodkumar | Properties of $Q\bar{Q}$ $(Q \epsilon b, c)$ mesons in Coulomb plus
Power potential | 22 Pages, 1 Figure | J.Phys.G36:035003,2009 | 10.1088/0954-3899/36/3/035003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The decay rates and spectroscopy of the $Q \bar Q$ $(Q \in c, b)$ mesons are
computed in non-relativistic phenomenological quark antiquark potential of the
type $V(r)=-\frac{\alpha_c}{r}+A r^{\nu}$, (CPP$_{\nu}$) with different choices
$\nu$. Numerical solution of the schrodinger equation has been used to obtain
the spectroscopy of $Q\bar{Q}$ mesons. The spin hyperfine, spin-orbit and
tensor components of the one gluon exchange interaction are employed to compute
the spectroscopy of the few lower $S$ and orbital excited states. The
numerically obtained radial solutions are employed to obtain the decay
constant, di-gamma and di-leptonic decay widths. The decay widths are
determined with and without radiative corrections. Present results are compared
with other potential model predictions as well as with the known experimental
values.
| [
{
"created": "Thu, 21 Aug 2008 08:57:24 GMT",
"version": "v1"
}
] | 2009-02-02 | [
[
"Patel",
"Bhavin",
""
],
[
"Vinodkumar",
"P. C.",
""
]
] | The decay rates and spectroscopy of the $Q \bar Q$ $(Q \in c, b)$ mesons are computed in non-relativistic phenomenological quark antiquark potential of the type $V(r)=-\frac{\alpha_c}{r}+A r^{\nu}$, (CPP$_{\nu}$) with different choices $\nu$. Numerical solution of the schrodinger equation has been used to obtain the spectroscopy of $Q\bar{Q}$ mesons. The spin hyperfine, spin-orbit and tensor components of the one gluon exchange interaction are employed to compute the spectroscopy of the few lower $S$ and orbital excited states. The numerically obtained radial solutions are employed to obtain the decay constant, di-gamma and di-leptonic decay widths. The decay widths are determined with and without radiative corrections. Present results are compared with other potential model predictions as well as with the known experimental values. |
1906.03046 | David Greynat | Giancarlo D'Ambrosio, David Greynat and Marc Knecht | Matching long and short distances at order ${\mathcal O}(\alpha_s)$ in
the form factors for $K\to\pi \ell^+\ell^-$ | 11 pages, 3 figures, uses elsarticle class, minor changes and typos
corrected, matches the published version | Phys. Lett. B 797 (2019) 134891 | 10.1016/j.physletb.2019.134891 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | At order ${\mathcal O}(\alpha G_{\mathrm F})$, the amplitudes for the decays
$K\to\pi \ell^+\ell^-$ involve a form factor given by the matrix element of the
time-ordered product of the electromagnetic current with the four-quark
operators describing weak non-leptonic neutral-current transitions between a
kaon and a pion. The short-distance behaviour of this time-ordered product,
when considered at order ${\mathcal O}(\alpha_s)$ in the perturbative expansion
of QCD, involves terms linear and quadratic in the logarithm of the Euclidean
momentum transfer squared. It is shown how one can exactly match these
short-distance features using a dispersive representation of the form factor,
with an absorptive part given by an infinite sum of zero-width resonances
following a Regge-type spectrum. Some phenomenology-related issues are briefly
discussed.
| [
{
"created": "Fri, 7 Jun 2019 12:24:38 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Sep 2019 17:00:16 GMT",
"version": "v2"
}
] | 2019-09-20 | [
[
"D'Ambrosio",
"Giancarlo",
""
],
[
"Greynat",
"David",
""
],
[
"Knecht",
"Marc",
""
]
] | At order ${\mathcal O}(\alpha G_{\mathrm F})$, the amplitudes for the decays $K\to\pi \ell^+\ell^-$ involve a form factor given by the matrix element of the time-ordered product of the electromagnetic current with the four-quark operators describing weak non-leptonic neutral-current transitions between a kaon and a pion. The short-distance behaviour of this time-ordered product, when considered at order ${\mathcal O}(\alpha_s)$ in the perturbative expansion of QCD, involves terms linear and quadratic in the logarithm of the Euclidean momentum transfer squared. It is shown how one can exactly match these short-distance features using a dispersive representation of the form factor, with an absorptive part given by an infinite sum of zero-width resonances following a Regge-type spectrum. Some phenomenology-related issues are briefly discussed. |
hep-ph/0312112 | Masanori Hirai | M. Hirai, S. Kumano, N. Saito (Asymmetry Analysis Collaboration) | Determination of polarized parton distribution functions and their
uncertainties | 9 pages, 15 eps figures, REVTeX, FORTRAN package is available at the
web site http://www-hs.phys.saga-u.ac.jp/aac.html. Replaced 3 eps figures in
Fig.2 | Phys.Rev.D69:054021,2004 | 10.1103/PhysRevD.69.054021 | SAGA-HE-200-03, KUNS1885 | hep-ph hep-ex nucl-ex nucl-th | null | We investigate the polarized parton distribution functions (PDFs) and their
uncertainties by using the world data on the spin asymmetry A_1. The
uncertainties of the polarized PDFs are estimated by the Hessian method. The up
and down valence-quark distributions are determined well. However, the
antiquark distributions have large uncertainties at this stage, and it is
particularly difficult to fix the gluon distribution. The \chi^2 analysis
produces a positively polarized gluon distribution, but even \Delta g(x)=0
could be allowed according to our uncertainty estimation. In comparison with
the previous AAC (Asymmetry Analysis Collaboration) parameterization in 2000,
accurate SLAC-E155 proton data are added to the analysis. We find that the E155
data improve the determination of the polarized PDFs, especially the polarized
antiquark distributions. In addition, the gluon-distribution uncertainties are
reduced due to the correlation with the antiquark distributions. We also show
the global analysis results with the condition \Delta g(x)=0 at the initial
scale, Q^2=1 GeV^2, for clarifying the error correlation effects with the gluon
distribution.
| [
{
"created": "Tue, 9 Dec 2003 04:36:51 GMT",
"version": "v1"
},
{
"created": "Thu, 18 Dec 2003 07:50:06 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Hirai",
"M.",
"",
"Asymmetry Analysis Collaboration"
],
[
"Kumano",
"S.",
"",
"Asymmetry Analysis Collaboration"
],
[
"Saito",
"N.",
"",
"Asymmetry Analysis Collaboration"
]
] | We investigate the polarized parton distribution functions (PDFs) and their uncertainties by using the world data on the spin asymmetry A_1. The uncertainties of the polarized PDFs are estimated by the Hessian method. The up and down valence-quark distributions are determined well. However, the antiquark distributions have large uncertainties at this stage, and it is particularly difficult to fix the gluon distribution. The \chi^2 analysis produces a positively polarized gluon distribution, but even \Delta g(x)=0 could be allowed according to our uncertainty estimation. In comparison with the previous AAC (Asymmetry Analysis Collaboration) parameterization in 2000, accurate SLAC-E155 proton data are added to the analysis. We find that the E155 data improve the determination of the polarized PDFs, especially the polarized antiquark distributions. In addition, the gluon-distribution uncertainties are reduced due to the correlation with the antiquark distributions. We also show the global analysis results with the condition \Delta g(x)=0 at the initial scale, Q^2=1 GeV^2, for clarifying the error correlation effects with the gluon distribution. |
2211.05073 | Gioacchino Piazza | Luca Di Luzio, Jorge Martin Camalich, Guido Martinelli, Jos\'e Antonio
Oller, Gioacchino Piazza | Axion-pion thermalization rate in unitarized NLO chiral perturbation
theory | 13 pages, 12 figures. Typos corrected and slightly changed results.
Extended discussion and appendix added | null | 10.1103/PhysRevD.108.035025 | null | hep-ph astro-ph.CO | http://creativecommons.org/licenses/by/4.0/ | We compute the axion-pion scattering $a \pi \to \pi \pi$, relevant for the
axion thermalization rate in the early universe, within unitarized NLO chiral
perturbation theory. The latter extends the range of validity of the chiral
expansion of axion-pion scattering and thus provides a crucial ingredient for
the reliable determination of the relic density of thermal axions, whenever the
axion decoupling temperature is below that of the QCD phase transition.
Implications for cosmological observables are briefly discussed.
| [
{
"created": "Wed, 9 Nov 2022 18:05:48 GMT",
"version": "v1"
},
{
"created": "Thu, 13 Jul 2023 16:45:54 GMT",
"version": "v2"
}
] | 2023-08-21 | [
[
"Di Luzio",
"Luca",
""
],
[
"Camalich",
"Jorge Martin",
""
],
[
"Martinelli",
"Guido",
""
],
[
"Oller",
"José Antonio",
""
],
[
"Piazza",
"Gioacchino",
""
]
] | We compute the axion-pion scattering $a \pi \to \pi \pi$, relevant for the axion thermalization rate in the early universe, within unitarized NLO chiral perturbation theory. The latter extends the range of validity of the chiral expansion of axion-pion scattering and thus provides a crucial ingredient for the reliable determination of the relic density of thermal axions, whenever the axion decoupling temperature is below that of the QCD phase transition. Implications for cosmological observables are briefly discussed. |
1611.00767 | Silvan Kuttimalai | Frank Krauss, Silvan Kuttimalai, Tilman Plehn | LHC multijet events as a probe for anomalous dimension-six gluon
interactions | null | Phys. Rev. D 95, 035024 (2017) | 10.1103/PhysRevD.95.035024 | IPPP/16/108, SLAC-PUB-1685 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Higher-dimensional multi-gluon interactions affect essentially all effective
Lagrangian analyses at the LHC. We show that, contrary to common lore, such
operators are best constrained in multi-jet production. Our limit on the
corresponding new physics scale in the multi-TeV range exceeds the typical
reach of global dimension-6 Higgs and top analyses. This implies that the pure
Yang-Mills operator can safely be neglected in almost all specific
higher-dimensional analyses at Run II.
| [
{
"created": "Wed, 2 Nov 2016 20:00:01 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Nov 2016 04:38:10 GMT",
"version": "v2"
},
{
"created": "Tue, 14 Feb 2017 19:38:21 GMT",
"version": "v3"
}
] | 2017-03-01 | [
[
"Krauss",
"Frank",
""
],
[
"Kuttimalai",
"Silvan",
""
],
[
"Plehn",
"Tilman",
""
]
] | Higher-dimensional multi-gluon interactions affect essentially all effective Lagrangian analyses at the LHC. We show that, contrary to common lore, such operators are best constrained in multi-jet production. Our limit on the corresponding new physics scale in the multi-TeV range exceeds the typical reach of global dimension-6 Higgs and top analyses. This implies that the pure Yang-Mills operator can safely be neglected in almost all specific higher-dimensional analyses at Run II. |
2402.17162 | Zhun Lu | Chentao Tan, Zhun Lu | Gluon GTMDs at nonzero skewness and impact parameter dependent parton
distributions | 12 pages,5 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by-nc-sa/4.0/ | We investigate the leading twist generalized transverse momentum dependent
parton distributions (GTMDs) of the unpolarized and longitudinally polarized
gluons in the nucleon. We adopt a light-front gluon-triquark model for the
nucleon motivated by soft-wall AdS/QCD. The gluon GTMDs are defined through the
off-forward gluon-gluon generalized correlator and are expressed as the overlap
of light-cone wave functions. The GTMDs can be employed to provide the
generalized parton distributions (GPDs) by integrating out the transverse
momentum. The Fourier transform of the GPDs encodes the parton distributions in
the transverse position space, namely, the impact parameter dependent parton
distributions (IPDs). We also calculate the three gluon IPDs corresponding to
the GPDs $H^g$, $E^g$ and $\widetilde{H}^g$, and present their dependence on
$x$ and $b_\perp$, respectively.
| [
{
"created": "Tue, 27 Feb 2024 02:47:58 GMT",
"version": "v1"
}
] | 2024-02-28 | [
[
"Tan",
"Chentao",
""
],
[
"Lu",
"Zhun",
""
]
] | We investigate the leading twist generalized transverse momentum dependent parton distributions (GTMDs) of the unpolarized and longitudinally polarized gluons in the nucleon. We adopt a light-front gluon-triquark model for the nucleon motivated by soft-wall AdS/QCD. The gluon GTMDs are defined through the off-forward gluon-gluon generalized correlator and are expressed as the overlap of light-cone wave functions. The GTMDs can be employed to provide the generalized parton distributions (GPDs) by integrating out the transverse momentum. The Fourier transform of the GPDs encodes the parton distributions in the transverse position space, namely, the impact parameter dependent parton distributions (IPDs). We also calculate the three gluon IPDs corresponding to the GPDs $H^g$, $E^g$ and $\widetilde{H}^g$, and present their dependence on $x$ and $b_\perp$, respectively. |
2407.01655 | Ajay Kumar Rai | Pooja Jakhad, Juhi Oudichhya, Ajay Kumar Rai | Interpretation of recently discovered single bottom baryons in the
relativistic flux tube model | 21 pages, 7 figures, Submitted in PRD | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Following recent experimental progress in the study of bottom baryons, we
systematically calculate the mass spectra of $\Lambda_{b}$, $\Xi_{b}$,
$\Sigma_{b}$, $\Xi_{b}^{'}$, and $\Omega_{b}$ baryons with a quark-diquark
picture in the framework of a relativistic flux tube model with spin-dependent
interactions in the j-j coupling scheme. Furthermore, we calculate the strong
decay width of bottom baryons decaying into a bottom baryon and a light
pseudoscalar meson. A good agreement is found between the calculated masses and
the experimentally available masses of singly bottom baryons. %We interpret
$\Sigma_{b}(6097)$ as a $1P(3/2^{-})$ state, $\Xi_{b}(6100)$ as $1P(1/2^{-})$
state of $\Xi_{b}$ baryon, $\Xi_{b}(6227)$ as a $1P(1/2^{-})$ or $1P(3/2^{-})$
state of $\Xi_{b}'$ baryon, $\Xi_{b}(6327)$ as a $1P(3/2^{-})$ state of
$\Xi_{b}'$ baryon, and $\Xi_{b}(6333)$ as a $1P(3/2^{-})$ state of $\Xi_{b}'$
baryon. By analysing both mass spectra and strong decay widths, we interpret
$\Sigma_{b}(6097)$ as a $1P(3/2^{-})$ state and $\Xi_{b}(6100)$ as a
$1P(1/2^{-})$ state of $\Xi_{b}$ baryon. The $\Xi_{b}(6227)$ is identified to
be an orbital excitation $1P$ of the $\Xi_{b}^{'}$ baryon with $J^{P}=3/2^{-}$.
Further, we determine $\Xi_{b}(6327)$ and $\Xi_{b}(6333)$ as a $1P(3/2^{-})$
state and $1P(5/2^{-})$ state, respectively, of $\Xi_{b}^{'}$ baryon. From the
obtained mass spectra, we construct the Regge trajectories in the $(J,M^{2})$
plane, which are found to be essentially linear, parallel, and equidistant. Our
predictions for higher orbital and radial excited states can help
experimentalists identify missing excited states of singly bottom baryons.
| [
{
"created": "Mon, 1 Jul 2024 14:06:15 GMT",
"version": "v1"
}
] | 2024-07-03 | [
[
"Jakhad",
"Pooja",
""
],
[
"Oudichhya",
"Juhi",
""
],
[
"Rai",
"Ajay Kumar",
""
]
] | Following recent experimental progress in the study of bottom baryons, we systematically calculate the mass spectra of $\Lambda_{b}$, $\Xi_{b}$, $\Sigma_{b}$, $\Xi_{b}^{'}$, and $\Omega_{b}$ baryons with a quark-diquark picture in the framework of a relativistic flux tube model with spin-dependent interactions in the j-j coupling scheme. Furthermore, we calculate the strong decay width of bottom baryons decaying into a bottom baryon and a light pseudoscalar meson. A good agreement is found between the calculated masses and the experimentally available masses of singly bottom baryons. %We interpret $\Sigma_{b}(6097)$ as a $1P(3/2^{-})$ state, $\Xi_{b}(6100)$ as $1P(1/2^{-})$ state of $\Xi_{b}$ baryon, $\Xi_{b}(6227)$ as a $1P(1/2^{-})$ or $1P(3/2^{-})$ state of $\Xi_{b}'$ baryon, $\Xi_{b}(6327)$ as a $1P(3/2^{-})$ state of $\Xi_{b}'$ baryon, and $\Xi_{b}(6333)$ as a $1P(3/2^{-})$ state of $\Xi_{b}'$ baryon. By analysing both mass spectra and strong decay widths, we interpret $\Sigma_{b}(6097)$ as a $1P(3/2^{-})$ state and $\Xi_{b}(6100)$ as a $1P(1/2^{-})$ state of $\Xi_{b}$ baryon. The $\Xi_{b}(6227)$ is identified to be an orbital excitation $1P$ of the $\Xi_{b}^{'}$ baryon with $J^{P}=3/2^{-}$. Further, we determine $\Xi_{b}(6327)$ and $\Xi_{b}(6333)$ as a $1P(3/2^{-})$ state and $1P(5/2^{-})$ state, respectively, of $\Xi_{b}^{'}$ baryon. From the obtained mass spectra, we construct the Regge trajectories in the $(J,M^{2})$ plane, which are found to be essentially linear, parallel, and equidistant. Our predictions for higher orbital and radial excited states can help experimentalists identify missing excited states of singly bottom baryons. |
1012.5033 | Dimiter Stamenov | Elliot Leader, Alexander V. Sidorov, Dimiter B. Stamenov | QCD Analysis of Polarized Inclusive and Semi-inclusive DIS Data | 13 pages, 6 figures, to be published in Proceedings of the Advanced
Studies Institute SYMMETRIES AND SPIN (Spin-Praha-2010), Prague, July 18-24,
2010 | null | null | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new combined NLO QCD analysis of the polarized inclusive and semi-inclusive
DIS data is presented. In contrast to previous combined analyses, the 1/Q^2
terms (kinematic - target mass corrections, and dynamic - higher twist
corrections) in the expression for the nucleon spin structure function g1 are
taken into account. The new COMPASS data are included in the analysis. The
impact of the semi-inclusive (SIDIS) data on the polarized parton densities
(PDFs) and on the higher twist corrections is demonstrated. The controversial
behavior of the polarized strange quark density obtained from the fit to the
DIS data alone, and a combined analysis of DIS and SIDIS data is discussed.
| [
{
"created": "Wed, 22 Dec 2010 16:55:51 GMT",
"version": "v1"
}
] | 2010-12-23 | [
[
"Leader",
"Elliot",
""
],
[
"Sidorov",
"Alexander V.",
""
],
[
"Stamenov",
"Dimiter B.",
""
]
] | A new combined NLO QCD analysis of the polarized inclusive and semi-inclusive DIS data is presented. In contrast to previous combined analyses, the 1/Q^2 terms (kinematic - target mass corrections, and dynamic - higher twist corrections) in the expression for the nucleon spin structure function g1 are taken into account. The new COMPASS data are included in the analysis. The impact of the semi-inclusive (SIDIS) data on the polarized parton densities (PDFs) and on the higher twist corrections is demonstrated. The controversial behavior of the polarized strange quark density obtained from the fit to the DIS data alone, and a combined analysis of DIS and SIDIS data is discussed. |
hep-ph/0103097 | Georgios Kraniotis | D. Bailin, G. V. Kraniotis and A. Love | Dark Matter Constraints in Heterotic M-Theory with Five-Brane Dominance | 10 pages, LaTeX file plus 8 EPS figures | JHEP 0109:019,2001 | 10.1088/1126-6708/2001/09/019 | SUSX-TH/01-006, RHCPP01-01T | hep-ph | null | The phenomenological implications of the M-theory limit in which
supersymmetry is broken by the auxiliary fields of five-brane moduli is
investigated.
Assuming that the lightest neutralino provides the dark matter in the
universe, constraints on the sparticle spectrum are obtained. Direct detection
rates for dark matter are estimated.
| [
{
"created": "Fri, 9 Mar 2001 19:49:53 GMT",
"version": "v1"
}
] | 2016-09-06 | [
[
"Bailin",
"D.",
""
],
[
"Kraniotis",
"G. V.",
""
],
[
"Love",
"A.",
""
]
] | The phenomenological implications of the M-theory limit in which supersymmetry is broken by the auxiliary fields of five-brane moduli is investigated. Assuming that the lightest neutralino provides the dark matter in the universe, constraints on the sparticle spectrum are obtained. Direct detection rates for dark matter are estimated. |
hep-ph/0508049 | Sanshiro Enomoto | S. Enomoto, E. Ohtani, K. Inoue, A. Suzuki | Neutrino geophysics with KamLAND and future prospects | 30 pages, 6 figures (color) | null | null | null | hep-ph | null | The Kamioka liquid scintillator anti-neutrino detector (KamLAND) is a
low-energy and low-background neutrino detector which could be a useful probe
for determining the U and Th abundances of the Earth. We constructed a model of
the Earth in order to evaluate the rate of geologically produced anti-neutrinos
(geo-neutrinos) detectable by KamLAND. We found that KamLAND can be used to
determine the absolute abundances of U and Th in the Earth with an accuracy
sufficient for placing important constraints on Earth's accretional process and
succeeding thermal history. The present observation of geo-neutrinos with
KamLAND is consistent with our model prediction based on the bulk silicate
Earth (BSE) composition within the uncertainty of the measurement. If a
neutrino detector were to be built in Hawaii, where effects of the continental
crust would be negligible, it could be used to estimate the U and Th content in
the lower mantle and the core. Our calculation of the geo-neutrino event rate
on the Earth's surface indicates that geo-neutrino observation can provide key
information for testing the current models for the content and distribution of
U and Th in the Earth.
| [
{
"created": "Wed, 3 Aug 2005 17:39:28 GMT",
"version": "v1"
},
{
"created": "Thu, 20 Oct 2005 17:55:09 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Enomoto",
"S.",
""
],
[
"Ohtani",
"E.",
""
],
[
"Inoue",
"K.",
""
],
[
"Suzuki",
"A.",
""
]
] | The Kamioka liquid scintillator anti-neutrino detector (KamLAND) is a low-energy and low-background neutrino detector which could be a useful probe for determining the U and Th abundances of the Earth. We constructed a model of the Earth in order to evaluate the rate of geologically produced anti-neutrinos (geo-neutrinos) detectable by KamLAND. We found that KamLAND can be used to determine the absolute abundances of U and Th in the Earth with an accuracy sufficient for placing important constraints on Earth's accretional process and succeeding thermal history. The present observation of geo-neutrinos with KamLAND is consistent with our model prediction based on the bulk silicate Earth (BSE) composition within the uncertainty of the measurement. If a neutrino detector were to be built in Hawaii, where effects of the continental crust would be negligible, it could be used to estimate the U and Th content in the lower mantle and the core. Our calculation of the geo-neutrino event rate on the Earth's surface indicates that geo-neutrino observation can provide key information for testing the current models for the content and distribution of U and Th in the Earth. |
0805.1133 | Koji Ishiwata | Koji Ishiwata, Shigeki Matsumoto, Takeo Moroi | High Energy Cosmic Rays from the Decay of Gravitino Dark Matter | 28 pages, 9 figures | Phys.Rev.D78:063505,2008 | 10.1103/PhysRevD.78.063505 | TU-818, UT-HET 009 | hep-ph astro-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study gamma ray and positron in high energy cosmic ray from the decay of
the gravitino dark matter in the framework of supersymmetric model with
R-parity violation. Even though R-parity is violated, the lifetime of the
gravitino, which is assumed to be the lightest superparticle, can be longer
than the present age of the universe if R-parity violating interactions are
weak enough. In such a case, gravitino can be dark matter of the universe and
its decay produces high energy cosmic rays. We calculate the fluxes of gamma
ray and positron from the decay of the gravitino dark matter and discuss
implications of such a scenario to present and future observations. In
particular, we show that excesses of the fluxes of gamma ray and positron
observed by EGRET and HEAT experiments, respectively, can be simultaneously
explained as the cosmic rays from the decay of the gravitino dark matter.
| [
{
"created": "Thu, 8 May 2008 10:29:58 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Aug 2008 05:29:00 GMT",
"version": "v2"
}
] | 2009-02-20 | [
[
"Ishiwata",
"Koji",
""
],
[
"Matsumoto",
"Shigeki",
""
],
[
"Moroi",
"Takeo",
""
]
] | We study gamma ray and positron in high energy cosmic ray from the decay of the gravitino dark matter in the framework of supersymmetric model with R-parity violation. Even though R-parity is violated, the lifetime of the gravitino, which is assumed to be the lightest superparticle, can be longer than the present age of the universe if R-parity violating interactions are weak enough. In such a case, gravitino can be dark matter of the universe and its decay produces high energy cosmic rays. We calculate the fluxes of gamma ray and positron from the decay of the gravitino dark matter and discuss implications of such a scenario to present and future observations. In particular, we show that excesses of the fluxes of gamma ray and positron observed by EGRET and HEAT experiments, respectively, can be simultaneously explained as the cosmic rays from the decay of the gravitino dark matter. |
hep-ph/0702071 | Valeriy Nazaruk | V. I. Nazaruk | Field-theoretical approach to particle oscillations in absorbing matter | 27 pages, 8 figures | Eur.Phys.J.C53:573-584,2008 | 10.1140/epjc/s10052-007-0473-6 | null | hep-ph nucl-th | null | The $ab$ oscillations in absorbing matter are considered. The standard model
based on optical potential does not describe the total $ab$ transition
probability as well as the channel corresponding to absorption of the
$b$-particle. We calculate directly the off-diagonal matrix element in the
framework of field-theoretical approach. Contrary to one-particle model, the
final state absorption does not tend to suppress the channels mentioned above
or, similarly, calculation with hermitian Hamiltonian leads to increase the
corresponding values. The model reproduces all the results on the particle
oscillations, however it is oriented to the description of the above-mentioned
channels. Also we touch on the problem of infrared singularities. The approach
under study is infrared-free.
| [
{
"created": "Wed, 7 Feb 2007 11:48:13 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Nazaruk",
"V. I.",
""
]
] | The $ab$ oscillations in absorbing matter are considered. The standard model based on optical potential does not describe the total $ab$ transition probability as well as the channel corresponding to absorption of the $b$-particle. We calculate directly the off-diagonal matrix element in the framework of field-theoretical approach. Contrary to one-particle model, the final state absorption does not tend to suppress the channels mentioned above or, similarly, calculation with hermitian Hamiltonian leads to increase the corresponding values. The model reproduces all the results on the particle oscillations, however it is oriented to the description of the above-mentioned channels. Also we touch on the problem of infrared singularities. The approach under study is infrared-free. |
hep-ph/0412387 | Andrzej Zembrzuski | Andrzej Zembrzuski | Isolated Photon Production in Deep Inelastic Compton Process at HERA | 99 pages, 44 figures, PhD thesis | null | null | null | hep-ph | null | The next-to-leading QCD calculation for the isolated photon and isolated
photon plus jet photoproduction at the ep collider DESY HERA is presented. The
theoretical uncertainties are discussed in details. The predictions are
compared with predictions of other authors and with data. The sensitivity of
the leading order cross section to the gluon density in both the real and the
virtual photon is discussed as well.
| [
{
"created": "Mon, 27 Dec 2004 12:08:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Zembrzuski",
"Andrzej",
""
]
] | The next-to-leading QCD calculation for the isolated photon and isolated photon plus jet photoproduction at the ep collider DESY HERA is presented. The theoretical uncertainties are discussed in details. The predictions are compared with predictions of other authors and with data. The sensitivity of the leading order cross section to the gluon density in both the real and the virtual photon is discussed as well. |
2305.08984 | Petr Grashin | P.Grashin and K.Sveshnikov | Spontaneous emission in the supercritical QED: what is wrong and what is
possible | arXiv admin note: substantial text overlap with arXiv:2209.00125,
arXiv:2201.04829 | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Spontaneous positron emission, caused by the supercritical Coulomb source
with charge $Z$ and size $R$, is explored in essentially non-perturbative
approach with emphasis on the VP-energy $\cal E_{VP}$, considered as a function
of the Coulomb source parameters $Z$ and $R$. The specific contribution to
$\cal E_{VP}$, which appears in the supercritical case due to direct Coulomb
interaction between VP-charge densities $\varrho_{VP}(\vec{r})$, is outlined
and studied in detail. It is shown that after first levels diving into the
lower continuum this contribution, being properly renormalized, turns out to be
negative in contrast to the classical electrostatics and so could play an
important role in spontaneous emission, especially for $Z$ just above the first
$Z_{cr,1}$. The additional problems of spontaneous emission, caused by the
lepton number conservation, are also discussed.
| [
{
"created": "Mon, 15 May 2023 19:52:33 GMT",
"version": "v1"
}
] | 2023-05-17 | [
[
"Grashin",
"P.",
""
],
[
"Sveshnikov",
"K.",
""
]
] | Spontaneous positron emission, caused by the supercritical Coulomb source with charge $Z$ and size $R$, is explored in essentially non-perturbative approach with emphasis on the VP-energy $\cal E_{VP}$, considered as a function of the Coulomb source parameters $Z$ and $R$. The specific contribution to $\cal E_{VP}$, which appears in the supercritical case due to direct Coulomb interaction between VP-charge densities $\varrho_{VP}(\vec{r})$, is outlined and studied in detail. It is shown that after first levels diving into the lower continuum this contribution, being properly renormalized, turns out to be negative in contrast to the classical electrostatics and so could play an important role in spontaneous emission, especially for $Z$ just above the first $Z_{cr,1}$. The additional problems of spontaneous emission, caused by the lepton number conservation, are also discussed. |
hep-ph/9310369 | John March-Russell | Markus A. Luty and John March-Russell | Baryons from Quarks in the $1/N$ Expansion | 27 pages, 5 uuencoded postscript figures, plain tex. References and
acknowledgements added. LBL-34778 | Nucl.Phys. B426 (1994) 71-93 | 10.1016/0550-3213(94)90126-0 | null | hep-ph nucl-th | null | We present a diagrammatic analysis of baryons in the $1/N$ expansion, where
$N$ is the number of QCD colors. We use this method to show that there are an
infinite number of degenerate baryon states in the large-$N$ limit. We also
show that forward matrix elements of quark bilinear operators satisfy the
static quark-model relations in this limit, and enumerate the corrections to
these relations to all orders in $1/N$. These results hold for any number of
light quark flavors, and the methods used can be extended to arbitrary
operators. Our results imply that for two flavors, the quark-model relations
for the axial currents and magnetic moments get corrections of order $1/N^2$.
For three or more flavors, the results are more complicated, and corrections
are generically of order $1/N$. We write an explicit effective lagrangian which
can be used to carry out chiral perturbation theory calculations in the $1/N$
expansion. Finally, we compare our results to what is expected from a chiral
constituent quark model.
| [
{
"created": "Thu, 28 Oct 1993 22:41:38 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Nov 1993 02:57:17 GMT",
"version": "v2"
},
{
"created": "Wed, 8 Dec 1993 01:29:19 GMT",
"version": "v3"
}
] | 2009-10-22 | [
[
"Luty",
"Markus A.",
""
],
[
"March-Russell",
"John",
""
]
] | We present a diagrammatic analysis of baryons in the $1/N$ expansion, where $N$ is the number of QCD colors. We use this method to show that there are an infinite number of degenerate baryon states in the large-$N$ limit. We also show that forward matrix elements of quark bilinear operators satisfy the static quark-model relations in this limit, and enumerate the corrections to these relations to all orders in $1/N$. These results hold for any number of light quark flavors, and the methods used can be extended to arbitrary operators. Our results imply that for two flavors, the quark-model relations for the axial currents and magnetic moments get corrections of order $1/N^2$. For three or more flavors, the results are more complicated, and corrections are generically of order $1/N$. We write an explicit effective lagrangian which can be used to carry out chiral perturbation theory calculations in the $1/N$ expansion. Finally, we compare our results to what is expected from a chiral constituent quark model. |
hep-ph/9310201 | Jonathan Bagger | Jonathan A. Bagger | Electroweak Symmetry Breaking at the Supercollider | JHU-TIPAC-93022. Five embedded eps figures, submitted as a uuencoded
file | null | null | null | hep-ph | null | Invited talk presented at the Workshop on Physics at Current Accelerators and
the Supercollider, Argonne, Illinois, and at the 17th Johns Hopkins Workshop on
Current Problems in Particle Theory, Budapest, Hungary.
| [
{
"created": "Fri, 1 Oct 1993 11:26:53 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bagger",
"Jonathan A.",
""
]
] | Invited talk presented at the Workshop on Physics at Current Accelerators and the Supercollider, Argonne, Illinois, and at the 17th Johns Hopkins Workshop on Current Problems in Particle Theory, Budapest, Hungary. |
hep-ph/0503229 | George W. S. Hou | Wei-Shu Hou | Highlights from Five Years at the B Factories | 16 pages, 5 figures, to appear as Brief Review in Mod. Phys. Lett. A | Mod.Phys.Lett.A20:707-724,2005 | 10.1142/S0217732305017020 | null | hep-ph hep-ex | null | The highlights and conflicts at the B Factories are briefly reviewed. $CP$
violation was established in 2001 in $B^0 \to J/\psi K_S$ and related modes,
which has now become a precision measurement of CP violation in $B^0$-$\bar
B^0$ mixing. However, the situation for the $B^0 \to \pi^+\pi^-$ and charmless
$b\to s$ modes, which probe also CP violation in the {\it decay} amplitude, are
not quite settled yet. They could be hinting at presence of both strong (CP
conserving) and new physics (CP violating) phases. We critically assess the
developments and discuss some related discrepancies and highlights, such as
observation of direct CP violation, and make a projection towards the next few
years.
| [
{
"created": "Wed, 23 Mar 2005 08:39:50 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Hou",
"Wei-Shu",
""
]
] | The highlights and conflicts at the B Factories are briefly reviewed. $CP$ violation was established in 2001 in $B^0 \to J/\psi K_S$ and related modes, which has now become a precision measurement of CP violation in $B^0$-$\bar B^0$ mixing. However, the situation for the $B^0 \to \pi^+\pi^-$ and charmless $b\to s$ modes, which probe also CP violation in the {\it decay} amplitude, are not quite settled yet. They could be hinting at presence of both strong (CP conserving) and new physics (CP violating) phases. We critically assess the developments and discuss some related discrepancies and highlights, such as observation of direct CP violation, and make a projection towards the next few years. |
hep-ph/0606036 | C. Q. Geng | C. Q. Geng and Y. K. Hsiao | Determination of Nucleon Form factors from Baryonic B Decays | 10 pages, 3 figures, final version to be published in PRD | Phys.Rev.D75:094005,2007 | 10.1103/PhysRevD.75.094005 | null | hep-ph | null | It is the first time that the study of three-body baryonic B decays offers an
independent determination of the nucleon form factors for the time-like four
momentum transfer $(t>0)$ region, such as $G^{p,n}_M(t)$ of vector currents and
those of axial ones. Explicitly, from the data of $\bar B^0\to n\bar p D^{*+}$
and $\Lambda\bar p\pi^+$ we find a constant ratio of
$G^n_M(t)/G^p_M(t)=-1.3\pm0.4$, which supports the FENICE experimental result.
The vector and axial-vector form factors of $p\bar n$, $p\bar p$ and $n\bar n$
pairs due to weak currents are also presented, which can be tested in future
experiments.
| [
{
"created": "Sat, 3 Jun 2006 09:02:04 GMT",
"version": "v1"
},
{
"created": "Tue, 17 Apr 2007 17:32:21 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Geng",
"C. Q.",
""
],
[
"Hsiao",
"Y. K.",
""
]
] | It is the first time that the study of three-body baryonic B decays offers an independent determination of the nucleon form factors for the time-like four momentum transfer $(t>0)$ region, such as $G^{p,n}_M(t)$ of vector currents and those of axial ones. Explicitly, from the data of $\bar B^0\to n\bar p D^{*+}$ and $\Lambda\bar p\pi^+$ we find a constant ratio of $G^n_M(t)/G^p_M(t)=-1.3\pm0.4$, which supports the FENICE experimental result. The vector and axial-vector form factors of $p\bar n$, $p\bar p$ and $n\bar n$ pairs due to weak currents are also presented, which can be tested in future experiments. |
2102.06623 | Jinfeng Liao | Dmitri E. Kharzeev and Jinfeng Liao | Chiral magnetic effect reveals the topology of gauge fields in heavy-ion
collisions | 22 pages, 5 figures; preprint version that closely matches the
published Perspective article at Nature Reviews Physics [Nature Rev. Phys. 3,
no.1, 55-63 (2021)] [https://www.nature.com/articles/s42254-020-00254-6] | Nature Rev. Phys. 3, no.1, 55-63 (2021) | 10.1038/s42254-020-00254-6 | null | hep-ph cond-mat.str-el hep-th nucl-ex nucl-th | http://creativecommons.org/licenses/by-nc-nd/4.0/ | The topological structure of vacuum is the cornerstone of non-Abelian gauge
theories describing strong and electroweak interactions within the standard
model of particle physics. However, transitions between different topological
sectors of the vacuum (believed to be at the origin of the baryon asymmetry of
the Universe) have never been observed directly. An experimental observation of
such transitions in Quantum Chromodynamics (QCD) has become possible in
heavy-ion collisions, where the chiral magnetic effect converts the chiral
asymmetry (generated by topological transitions in hot QCD matter) into an
electric current, under the presence of the magnetic field produced by the
colliding ions. The Relativistic Heavy Ion Collider program on heavy-ion
collisions such as the Zr-Zr and Ru-Ru isobars, thus has the potential to
uncover the topological structure of vacuum in a laboratory experiment. This
discovery would have far-reaching implications for the understanding of QCD,
the origin of the baryon asymmetry in the present-day Universe, and for other
areas, including condensed matter physics.
| [
{
"created": "Fri, 12 Feb 2021 17:08:43 GMT",
"version": "v1"
}
] | 2021-02-15 | [
[
"Kharzeev",
"Dmitri E.",
""
],
[
"Liao",
"Jinfeng",
""
]
] | The topological structure of vacuum is the cornerstone of non-Abelian gauge theories describing strong and electroweak interactions within the standard model of particle physics. However, transitions between different topological sectors of the vacuum (believed to be at the origin of the baryon asymmetry of the Universe) have never been observed directly. An experimental observation of such transitions in Quantum Chromodynamics (QCD) has become possible in heavy-ion collisions, where the chiral magnetic effect converts the chiral asymmetry (generated by topological transitions in hot QCD matter) into an electric current, under the presence of the magnetic field produced by the colliding ions. The Relativistic Heavy Ion Collider program on heavy-ion collisions such as the Zr-Zr and Ru-Ru isobars, thus has the potential to uncover the topological structure of vacuum in a laboratory experiment. This discovery would have far-reaching implications for the understanding of QCD, the origin of the baryon asymmetry in the present-day Universe, and for other areas, including condensed matter physics. |
2306.09317 | John Terry | Mei-Sen Gao, Zhong-Bo Kang, Ding Yu Shao, John Terry, Cheng Zhang | QCD resummation of dijet azimuthal decorrelations in pp and pA
collisions | 26 pages, 6 figures | JHEP 10, 013 (2023) | 10.1007/JHEP10(2023)013 | LA-UR-23-24761 | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the azimuthal angular decorrelations of dijet production in both
proton-proton (pp) and proton-nucleus (pA) collisions. By utilizing
soft-collinear effective theory, we establish the factorization and resummation
formalism at the next-to-leading logarithmic accuracy for the azimuthal angular
decorrelations in the back-to-back limit in pp collisions. We propose an
approach where the nuclear modifications to dijet production in pA collisions
are accounted for in the nuclear modified transverse momentum dependent parton
distribution functions (nTMDPDFs), which contain both collinear and transverse
dynamics. This approach naturally generalizes the well-established formalism
related to the nuclear modified collinear parton distribution functions
(nPDFs). We demonstrate strong consistency between our methodology and the CMS
measurements in both pp and pA collisions, and make predictions for dijet
production in the forward rapidity region in pA collisions at LHC kinematics
and for mid-rapidity kinematics at sPHENIX. Throughout this paper, we focus on
the application of this formalism to a simultaneous fit to both collinear and
transverse momentum dependent contributions to the transverse momentum
dependent distributions.
| [
{
"created": "Thu, 15 Jun 2023 17:52:37 GMT",
"version": "v1"
},
{
"created": "Thu, 19 Oct 2023 21:57:07 GMT",
"version": "v2"
}
] | 2023-10-23 | [
[
"Gao",
"Mei-Sen",
""
],
[
"Kang",
"Zhong-Bo",
""
],
[
"Shao",
"Ding Yu",
""
],
[
"Terry",
"John",
""
],
[
"Zhang",
"Cheng",
""
]
] | We study the azimuthal angular decorrelations of dijet production in both proton-proton (pp) and proton-nucleus (pA) collisions. By utilizing soft-collinear effective theory, we establish the factorization and resummation formalism at the next-to-leading logarithmic accuracy for the azimuthal angular decorrelations in the back-to-back limit in pp collisions. We propose an approach where the nuclear modifications to dijet production in pA collisions are accounted for in the nuclear modified transverse momentum dependent parton distribution functions (nTMDPDFs), which contain both collinear and transverse dynamics. This approach naturally generalizes the well-established formalism related to the nuclear modified collinear parton distribution functions (nPDFs). We demonstrate strong consistency between our methodology and the CMS measurements in both pp and pA collisions, and make predictions for dijet production in the forward rapidity region in pA collisions at LHC kinematics and for mid-rapidity kinematics at sPHENIX. Throughout this paper, we focus on the application of this formalism to a simultaneous fit to both collinear and transverse momentum dependent contributions to the transverse momentum dependent distributions. |
1307.2308 | Lei Guo | Li Xiao-Peng, Guo Lei, Ma Wen-Gan, Zhang Ren-You, Han Liang, and Song
Mao | Single (anti-)top quark production in association with a lightest
neutralino at LHeC | 21 pages, 10 figures | Phys. Rev. D 88, 014023 (2013) | 10.1103/PhysRevD.88.014023 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this paper we examine thoroughly the single (anti-)top quark production
associated with a lightest neutralino at the possible CERN Large Hadron
Electron Collider (LHeC). We calculate the full next-to-leading order (NLO) QCD
corrections to the process including all the nonresonant diagrams and do not
assume the production and decay factorization for the possible resonant top
squarks in the R-parity violating minimal supersymmetric standard model with 19
unrelated parameters. We investigate numerically the effects of the relevant
supersymmetry (SUSY) parameters on the cross section, and present the
transverse momentum distributions of final (anti-)top quark at both the
leading-order (LO) and the QCD NLO. We find that the NLO QCD corrections
enhance the LO cross sections in most chosen parameter space, and the NLO QCD
impacts on the transverse momentum distributions of the final (anti-)top quark
might be resolvable in some cases. We conclude that even with recently known
experimental constraints the on SUSY parameters, the production rate could
still achieve notable value in the admissible parameter space.
| [
{
"created": "Tue, 9 Jul 2013 00:02:00 GMT",
"version": "v1"
},
{
"created": "Mon, 22 Jul 2013 01:49:32 GMT",
"version": "v2"
}
] | 2013-07-23 | [
[
"Xiao-Peng",
"Li",
""
],
[
"Lei",
"Guo",
""
],
[
"Wen-Gan",
"Ma",
""
],
[
"Ren-You",
"Zhang",
""
],
[
"Liang",
"Han",
""
],
[
"Mao",
"Song",
""
]
] | In this paper we examine thoroughly the single (anti-)top quark production associated with a lightest neutralino at the possible CERN Large Hadron Electron Collider (LHeC). We calculate the full next-to-leading order (NLO) QCD corrections to the process including all the nonresonant diagrams and do not assume the production and decay factorization for the possible resonant top squarks in the R-parity violating minimal supersymmetric standard model with 19 unrelated parameters. We investigate numerically the effects of the relevant supersymmetry (SUSY) parameters on the cross section, and present the transverse momentum distributions of final (anti-)top quark at both the leading-order (LO) and the QCD NLO. We find that the NLO QCD corrections enhance the LO cross sections in most chosen parameter space, and the NLO QCD impacts on the transverse momentum distributions of the final (anti-)top quark might be resolvable in some cases. We conclude that even with recently known experimental constraints the on SUSY parameters, the production rate could still achieve notable value in the admissible parameter space. |
1112.2102 | Chian-Shu Chen | Chian-Shu Chen and Ryo Takahashi | Hierarchically Acting Sterile Neutrinos | 4 pages, 1 table | null | 10.1140/epjc/s10052-012-2089-8 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose that a hierarchical spectrum of sterile neutrinos (eV, keV,
$10^{13-15}$ GeV) is considered to as the explanations for MiniBooNE and LSND
oscillation anomalies, dark matter, and baryon asymmetry of the universe (BAU)
respectively. The scenario can also realize the smallness of active neutrino
masses by seesaw mechanism.
| [
{
"created": "Fri, 9 Dec 2011 13:54:49 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Chen",
"Chian-Shu",
""
],
[
"Takahashi",
"Ryo",
""
]
] | We propose that a hierarchical spectrum of sterile neutrinos (eV, keV, $10^{13-15}$ GeV) is considered to as the explanations for MiniBooNE and LSND oscillation anomalies, dark matter, and baryon asymmetry of the universe (BAU) respectively. The scenario can also realize the smallness of active neutrino masses by seesaw mechanism. |
1803.08239 | Mrinal Kumar Das | Ananya Mukherjee, Mrinal Kumar Das, Jayanta Kumar Sarma | Normal hierarchy neutrino mass model revisited with leptogenesis | 25pages, 8 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have studied the scenario of baryogenesis via leptogenesis in an $A_4$
flavor symmetric framework considering type I seesaw as the origin of neutrino
mass. Because of the presence of the fifth generation right handed neutrino the
model naturally generates non-zero reactor mixing angle. We have considered two
vev alignments for the extra flavon $\eta$ and studied the consequences in
detail. As a whole the additional flavon along with the extra right handed
neutrinos allow us to study thermal leptogenesis by the decay of the lightest
right handed neutrino present in the model. We have computed the
matter-antimatter asymmetry for both flavor dependent and flavor independent
leptogenesis by considering a considerably wider range of right handed neutrino
mass. Finally, we correlate the baryon asymmetry of the universe (BAU) with the
model parameters and light neutrino masses.
| [
{
"created": "Thu, 22 Mar 2018 06:14:21 GMT",
"version": "v1"
}
] | 2018-03-23 | [
[
"Mukherjee",
"Ananya",
""
],
[
"Das",
"Mrinal Kumar",
""
],
[
"Sarma",
"Jayanta Kumar",
""
]
] | We have studied the scenario of baryogenesis via leptogenesis in an $A_4$ flavor symmetric framework considering type I seesaw as the origin of neutrino mass. Because of the presence of the fifth generation right handed neutrino the model naturally generates non-zero reactor mixing angle. We have considered two vev alignments for the extra flavon $\eta$ and studied the consequences in detail. As a whole the additional flavon along with the extra right handed neutrinos allow us to study thermal leptogenesis by the decay of the lightest right handed neutrino present in the model. We have computed the matter-antimatter asymmetry for both flavor dependent and flavor independent leptogenesis by considering a considerably wider range of right handed neutrino mass. Finally, we correlate the baryon asymmetry of the universe (BAU) with the model parameters and light neutrino masses. |
1704.07397 | Bhubanjyoti Bhattacharya | Ashutosh Kumar Alok, Bhubanjyoti Bhattacharya, Alakabha Datta, Dinesh
Kumar, Jacky Kumar, and David London | New Physics in $b \to s \mu^+ \mu^-$ after the Measurement of $R_{K^*}$ | 18 pages, 1 figure; final version accepted for publication in
Physical Review D | Phys. Rev. D 96, 095009 (2017) | 10.1103/PhysRevD.96.095009 | UdeM-GPP-TH-17-256, WSU-HEP-1708 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The recent measurement of $R_{K^*}$ is yet another hint of new physics (NP),
and supports the idea that it is present in $b\to s\mu^+\mu^-$ decays. We
perform a combined model-independent and model-dependent analysis in order to
deduce properties of this NP. Like others, we find that the NP must obey one of
two scenarios: (I) $C_9^{\mu\mu}({\rm NP}) < 0$ or (II) $C_9^{\mu\mu}({\rm NP})
= - C_{10}^{\mu\mu}({\rm NP}) < 0$. A third scenario, (III) $C_9^{\mu\mu}({\rm
NP}) = - C_{9}^{\prime \mu\mu}({\rm NP})$, is rejected largely because it
predicts $R_K = 1$, in disagreement with experiment. The simplest NP models
involve the tree-level exchange of a leptoquark (LQ) or a $Z'$ boson. We show
that scenario (II) can arise in LQ or $Z'$ models, but scenario (I) is only
possible with a $Z'$. Fits to $Z'$ models must take into account the additional
constraints from $B^0_s$-${\bar B}^0_s$ mixing and neutrino trident production.
Although the LQs must be heavy, O(TeV), we find that the $Z'$ can be light,
e.g., $M_{Z'} = 10$ GeV or 200 MeV.
| [
{
"created": "Mon, 24 Apr 2017 18:01:28 GMT",
"version": "v1"
},
{
"created": "Tue, 2 May 2017 15:39:10 GMT",
"version": "v2"
},
{
"created": "Wed, 18 Oct 2017 18:31:23 GMT",
"version": "v3"
}
] | 2017-11-21 | [
[
"Alok",
"Ashutosh Kumar",
""
],
[
"Bhattacharya",
"Bhubanjyoti",
""
],
[
"Datta",
"Alakabha",
""
],
[
"Kumar",
"Dinesh",
""
],
[
"Kumar",
"Jacky",
""
],
[
"London",
"David",
""
]
] | The recent measurement of $R_{K^*}$ is yet another hint of new physics (NP), and supports the idea that it is present in $b\to s\mu^+\mu^-$ decays. We perform a combined model-independent and model-dependent analysis in order to deduce properties of this NP. Like others, we find that the NP must obey one of two scenarios: (I) $C_9^{\mu\mu}({\rm NP}) < 0$ or (II) $C_9^{\mu\mu}({\rm NP}) = - C_{10}^{\mu\mu}({\rm NP}) < 0$. A third scenario, (III) $C_9^{\mu\mu}({\rm NP}) = - C_{9}^{\prime \mu\mu}({\rm NP})$, is rejected largely because it predicts $R_K = 1$, in disagreement with experiment. The simplest NP models involve the tree-level exchange of a leptoquark (LQ) or a $Z'$ boson. We show that scenario (II) can arise in LQ or $Z'$ models, but scenario (I) is only possible with a $Z'$. Fits to $Z'$ models must take into account the additional constraints from $B^0_s$-${\bar B}^0_s$ mixing and neutrino trident production. Although the LQs must be heavy, O(TeV), we find that the $Z'$ can be light, e.g., $M_{Z'} = 10$ GeV or 200 MeV. |
hep-ph/0003202 | Jin Hongying | H.Y. Jin and J.G. K\"orner | Radiative correction of the correlator for (0^{++},1$^{-+}$) light
hybrid | References added and Text improved | Phys.Rev.D64:074002,2001 | 10.1103/PhysRevD.64.074002 | null | hep-ph | null | We calculate the radiative corrections to the current-current correlator of
the hybrid current $g\bar q(x)\gamma_{\nu}iG_{\mu\nu}^aT^aq(x)$. Based on this
new result we use the QCD sum rule approach to estimate lower bounds on the
masses of the $J^{PC}$=$1^{-+}$ and $0^{++}$ light hybrids.
| [
{
"created": "Tue, 21 Mar 2000 13:33:59 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Apr 2000 17:23:20 GMT",
"version": "v2"
},
{
"created": "Thu, 8 Jun 2000 10:28:47 GMT",
"version": "v3"
}
] | 2016-09-06 | [
[
"Jin",
"H. Y.",
""
],
[
"Körner",
"J. G.",
""
]
] | We calculate the radiative corrections to the current-current correlator of the hybrid current $g\bar q(x)\gamma_{\nu}iG_{\mu\nu}^aT^aq(x)$. Based on this new result we use the QCD sum rule approach to estimate lower bounds on the masses of the $J^{PC}$=$1^{-+}$ and $0^{++}$ light hybrids. |
hep-ph/0012076 | Steve King | S. F. King and D. A. J. Rayner | Brane Mediated Supersymmetry Breaking | Version to appear in Nucl.Phys.B. 28 pages, Latex | Nucl.Phys. B607 (2001) 77-98 | 10.1016/S0550-3213(01)00220-6 | null | hep-ph hep-th | null | We propose a mechanism for mediating supersymmetry breaking in Type I string
constructions. The basic set-up consists of a system of three D-branes: two
parallel D-branes, a matter D-brane and a source D-brane, with supersymmetry
breaking communicated via a third D-brane, the mediating D-brane, which
intersects both of the parallel D-branes. We discuss an example in which the
first and second family matter fields correspond to open strings living on the
intersection of the matter D-brane and mediating D-brane, while the gauge
fields, Higgs doublets and third family matter fields correspond to open
strings living on the mediating D-brane. As in gaugino mediated models, the
gauginos and Higgs doublets receive direct soft masses from the source brane,
and flavour-changing neutral currents are naturally suppressed since the first
and second family squarks and sleptons receive suppressed soft masses. However,
unlike the gaugino mediated model, the third family squarks and sleptons
receive unsuppressed soft masses, resulting in a very distinctive spectrum with
heavier stops, sbottoms and staus.
| [
{
"created": "Wed, 6 Dec 2000 21:19:06 GMT",
"version": "v1"
},
{
"created": "Wed, 13 Dec 2000 17:47:16 GMT",
"version": "v2"
},
{
"created": "Mon, 21 May 2001 09:26:55 GMT",
"version": "v3"
}
] | 2009-10-31 | [
[
"King",
"S. F.",
""
],
[
"Rayner",
"D. A. J.",
""
]
] | We propose a mechanism for mediating supersymmetry breaking in Type I string constructions. The basic set-up consists of a system of three D-branes: two parallel D-branes, a matter D-brane and a source D-brane, with supersymmetry breaking communicated via a third D-brane, the mediating D-brane, which intersects both of the parallel D-branes. We discuss an example in which the first and second family matter fields correspond to open strings living on the intersection of the matter D-brane and mediating D-brane, while the gauge fields, Higgs doublets and third family matter fields correspond to open strings living on the mediating D-brane. As in gaugino mediated models, the gauginos and Higgs doublets receive direct soft masses from the source brane, and flavour-changing neutral currents are naturally suppressed since the first and second family squarks and sleptons receive suppressed soft masses. However, unlike the gaugino mediated model, the third family squarks and sleptons receive unsuppressed soft masses, resulting in a very distinctive spectrum with heavier stops, sbottoms and staus. |
1111.6935 | Yogiro Hama | Yogiro Hama (1), Rone P.G. Andrade (1), Frederique Grassi (1) and
Wei-Liang Qian (2) ((1) Instituto de Fisica, Universidade de Sao Paulo, Sao
Paulo, Brazil, (2) Departamento de Fisica, Universidade Federal de Ouro
Preto, Ouro Preto-MG, Brazil) | On the Origin of the Trigger-Angle Dependence of the Ridge Structure | 4 pages, 4 figures, prepared for ISMD 2011 Proceedings | Prog.Theor.Phys.Suppl. 193 (2012) 167-171 | 10.1143/PTPS.193.167 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The origin of the trigger-angle dependence of the ridge structure in
two-hadron long-range correlations, as observed at RHIC, is discussed as due to
an interplay between the elliptic flow caused by the initial state global
geometry and flow produced by fluctuations.
| [
{
"created": "Tue, 29 Nov 2011 19:09:01 GMT",
"version": "v1"
}
] | 2015-06-03 | [
[
"Hama",
"Yogiro",
""
],
[
"Andrade",
"Rone P. G.",
""
],
[
"Grassi",
"Frederique",
""
],
[
"Qian",
"Wei-Liang",
""
]
] | The origin of the trigger-angle dependence of the ridge structure in two-hadron long-range correlations, as observed at RHIC, is discussed as due to an interplay between the elliptic flow caused by the initial state global geometry and flow produced by fluctuations. |
0809.0713 | Sannino Francesco | Thomas A. Ryttov (CERN & Niels Bohr), Francesco Sannino (HEC,
University of Southern Denmark) | Ultra Minimal Technicolor and its Dark Matter TIMP | RevTeX, 31 pages. 9 figures | Phys.Rev.D78:115010,2008 | 10.1103/PhysRevD.78.115010 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We introduce an explicit model with technifermion matter transforming
according to multiple representations of the underlying technicolor gauge
group. The model features simultaneously the smallest possible value of the
naive S parameter and the smallest possible number of technifermions. The
chiral dynamics is extremely rich. We construct the low-energy effective
Lagrangian. We provide both the linearly and non-linearly realized ones. We
then embed, in a natural way, the Standard Model (SM) interactions within the
global symmetries of the underlying gauge theory. Several low-energy composite
particles are SM singlets. One of these Technicolor Interacting Massive
Particles (TIMP)s is a natural cold dark matter (DM) candidate. We estimate the
fraction of the mass in the universe constituted by our DM candidate over the
baryon one. We show that the new TIMP, differently from earlier models, can be
sufficiently light to be directly produced and studied at the Large Hadron
Collider (LHC).
| [
{
"created": "Wed, 3 Sep 2008 21:21:08 GMT",
"version": "v1"
}
] | 2008-12-30 | [
[
"Ryttov",
"Thomas A.",
"",
"CERN & Niels Bohr"
],
[
"Sannino",
"Francesco",
"",
"HEC,\n University of Southern Denmark"
]
] | We introduce an explicit model with technifermion matter transforming according to multiple representations of the underlying technicolor gauge group. The model features simultaneously the smallest possible value of the naive S parameter and the smallest possible number of technifermions. The chiral dynamics is extremely rich. We construct the low-energy effective Lagrangian. We provide both the linearly and non-linearly realized ones. We then embed, in a natural way, the Standard Model (SM) interactions within the global symmetries of the underlying gauge theory. Several low-energy composite particles are SM singlets. One of these Technicolor Interacting Massive Particles (TIMP)s is a natural cold dark matter (DM) candidate. We estimate the fraction of the mass in the universe constituted by our DM candidate over the baryon one. We show that the new TIMP, differently from earlier models, can be sufficiently light to be directly produced and studied at the Large Hadron Collider (LHC). |
1010.4550 | Joel Walker | Tianjun Li, James A. Maxin, Dimitri V. Nanopoulos, and Joel W. Walker | Super No-Scale F-SU(5): A Dynamic Determination of M_{1/2} and tan beta | V2, As accepted to Physics Letters B; 8 Pages, 2 Plots, 1 Table | Phys.Lett.B703:469-474,2011 | 10.1016/j.physletb.2011.08.025 | ACT-12-10, MIFPA-10-45 | hep-ph astro-ph.CO hep-ex hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the Higgs potential in No-Scale F-SU(5), a model built on the
tripodal foundations of the Flipped SU(5) x U(1)_X Grand Unified Theory, extra
F-theory derived TeV scale vector-like particle multiplets, and the high scale
boundary conditions of No-Scale Supergravity. V_min, the minimum of the
potential following radiative electroweak symmetry breaking, is a function at
fixed Z-Boson mass of the universal gaugino boundary mass M_{1/2} and
tan{\beta}, the ratio of Higgs vacuum expectation values. The No-Scale
nullification of the bilinear Higgs soft term B_mu at the boundary reduces
V_min(M_{1/2}) to a one dimensional dependency, which may be secondarily
minimized. This "Super No-Scale" condition dynamically fixes tan beta and
M_{1/2} at the local minimum minimorum of V_min. Fantastically, the walls of
this theoretically established secondary potential coalesce in descent to a
striking concurrency with the previously phenomenologically favored "golden
point" and "golden strip".
| [
{
"created": "Thu, 21 Oct 2010 18:30:29 GMT",
"version": "v1"
},
{
"created": "Tue, 6 Sep 2011 07:30:01 GMT",
"version": "v2"
}
] | 2011-09-13 | [
[
"Li",
"Tianjun",
""
],
[
"Maxin",
"James A.",
""
],
[
"Nanopoulos",
"Dimitri V.",
""
],
[
"Walker",
"Joel W.",
""
]
] | We study the Higgs potential in No-Scale F-SU(5), a model built on the tripodal foundations of the Flipped SU(5) x U(1)_X Grand Unified Theory, extra F-theory derived TeV scale vector-like particle multiplets, and the high scale boundary conditions of No-Scale Supergravity. V_min, the minimum of the potential following radiative electroweak symmetry breaking, is a function at fixed Z-Boson mass of the universal gaugino boundary mass M_{1/2} and tan{\beta}, the ratio of Higgs vacuum expectation values. The No-Scale nullification of the bilinear Higgs soft term B_mu at the boundary reduces V_min(M_{1/2}) to a one dimensional dependency, which may be secondarily minimized. This "Super No-Scale" condition dynamically fixes tan beta and M_{1/2} at the local minimum minimorum of V_min. Fantastically, the walls of this theoretically established secondary potential coalesce in descent to a striking concurrency with the previously phenomenologically favored "golden point" and "golden strip". |
0804.1014 | Hiroshi Yokoya | Kaoru Hagiwara, Yukinari Sumino, Hiroshi Yokoya | Bound-state Effects on Top Quark Production at Hadron Colliders | 14 page, 6 figures; hard-vertex factors modified; cross sections
changed accordingly; all qualitative features unchanged, nevertheless;
discussion and references added; version to appear in PLB | Phys.Lett.B666:71-76,2008 | 10.1016/j.physletb.2008.07.006 | KEK-TH-1231, TU-811, CERN-PH-TH/2008-045 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study bound-state effects on the t\bar{t} production cross section in the
threshold region at hadron colliders. The bound-state effects are important
particularly at the LHC where the gluon fusion is the dominant subprocess. Due
to the formation of t\bar{t} resonances in the J=0 color-singlet channel of gg
\to t\bar{t} and the large width of the top quark, the t\bar{t} invariant-mass
distribution peaks at a few GeV below the t\bar{t} threshold, and it is
significantly enhanced over the naive NLO prediction until several GeV above
the threshold. We present predictions of the t\bar{t} invariant-mass
distribution which incorporate both the bound-state effects and initial-state
radiations up to NLO. The bound-state effects would lead to a substantial
deformation of top-quark kinematical distributions in the threshold region.
| [
{
"created": "Mon, 7 Apr 2008 14:19:36 GMT",
"version": "v1"
},
{
"created": "Tue, 1 Jul 2008 20:54:14 GMT",
"version": "v2"
}
] | 2009-09-17 | [
[
"Hagiwara",
"Kaoru",
""
],
[
"Sumino",
"Yukinari",
""
],
[
"Yokoya",
"Hiroshi",
""
]
] | We study bound-state effects on the t\bar{t} production cross section in the threshold region at hadron colliders. The bound-state effects are important particularly at the LHC where the gluon fusion is the dominant subprocess. Due to the formation of t\bar{t} resonances in the J=0 color-singlet channel of gg \to t\bar{t} and the large width of the top quark, the t\bar{t} invariant-mass distribution peaks at a few GeV below the t\bar{t} threshold, and it is significantly enhanced over the naive NLO prediction until several GeV above the threshold. We present predictions of the t\bar{t} invariant-mass distribution which incorporate both the bound-state effects and initial-state radiations up to NLO. The bound-state effects would lead to a substantial deformation of top-quark kinematical distributions in the threshold region. |
hep-ph/0311301 | Tamas Biro S. | Tamas S. Biro, Gabor Purcsel and Berndt Muller | How low is the thermodynamical limit? | Talk presented at NATO School "Structure and Dynamics of Elementary
Matter", Kemar, Turkey, Sept.22.-Oct.2, 2003 by T.S.Biro. LateX, special
style file, 4 extra .ps files | null | null | null | hep-ph | null | We analyze how can some dynamical process lead to (almost) exponential
distribution of hadrons without instantaneous equipartition with a heat bath.
We present a model for parton dressing whic re-combines the exponential from
cut power law minijet distributions as a limiting distribution. Thermal models
and power law tails are interpreted within the framework of the more general
Tsallis distribution.
| [
{
"created": "Mon, 24 Nov 2003 11:28:15 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Biro",
"Tamas S.",
""
],
[
"Purcsel",
"Gabor",
""
],
[
"Muller",
"Berndt",
""
]
] | We analyze how can some dynamical process lead to (almost) exponential distribution of hadrons without instantaneous equipartition with a heat bath. We present a model for parton dressing whic re-combines the exponential from cut power law minijet distributions as a limiting distribution. Thermal models and power law tails are interpreted within the framework of the more general Tsallis distribution. |
hep-ph/9802445 | Utpal Sarkar | Ernest Ma and Utpal Sarkar | Neutrino Masses and Leptogenesis with Heavy Higgs Triplets | 12 pages including one figure | Phys.Rev.Lett. 80 (1998) 5716-5719 | 10.1103/PhysRevLett.80.5716 | UCRHEP-T209 | hep-ph | null | A simple and economical extension of the minimal standard electroweak gauge
model (without right-handed neutrinos) by the addition of two heavy Higgs
scalar triplets would have two significant advantages. \underline {Naturally}
small Majorana neutrino masses would become possible, as well as leptogenesis
in the early universe which gets converted at the electroweak phase transition
into the present observed baryon asymmetry.
| [
{
"created": "Fri, 27 Feb 1998 11:16:03 GMT",
"version": "v1"
},
{
"created": "Fri, 29 May 1998 13:15:09 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Ma",
"Ernest",
""
],
[
"Sarkar",
"Utpal",
""
]
] | A simple and economical extension of the minimal standard electroweak gauge model (without right-handed neutrinos) by the addition of two heavy Higgs scalar triplets would have two significant advantages. \underline {Naturally} small Majorana neutrino masses would become possible, as well as leptogenesis in the early universe which gets converted at the electroweak phase transition into the present observed baryon asymmetry. |
1306.1423 | Sandhya Choubey | Anushree Ghosh, Sandhya Choubey | Measuring the Mass Hierarchy with Muon and Hadron Events in Atmospheric
Neutrino Experiments | 29 pages | null | 10.1007/JHEP10(2013)174 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Neutrino mass hierarchy can be measured in atmospheric neutrino experiments
through the observation of earth matter effects. Magnetized iron calorimeters
have been shown to be good in this regard due to their charge identification
capabilities. The charged current interaction of $\nu_\mu$ in this detector,
produces a muon track and a hadron shower. The direction of the muon track can
be measured very accurately. We show the improvement expected in the reach of
this class of experiments to the neutrino mass hierarchy, as we improve the
muon energy resolution and the muon reconstruction efficiency. We next propose
to include the hadron events in the analysis, by tagging them with the zenith
angle of the corresponding muon and binning the hadron data first in energy and
then in zenith angle. To the best of our knowledge this way of performing the
analysis of the atmospheric neutrino data has not be considered before. We show
that the hadron events increase the mass hierarchy sensitivity of the
experiment. Finally, we show the expected mass hierarchy sensitivity in terms
of the reconstructed neutrino energy and zenith angle. We show how the detector
resolutions spoil the earth matter effects in the neutrino channel and argue
why the sensitivity obtained from the neutrino analysis cannot be significantly
better than that obtained from the analysis using muon data alone. As a result,
the best mass hierarchy sensitivity is obtained when we add the contribution of
the muon and the hadron data. For $\sin^22\theta_{13}=0.1$,
$\sin^2\theta_{23}=0.5$, a muon energy resolution of 2\%, reconstruction
efficiency of 80\% and exposure of $50\times 10$ kton-year, we could get up to
$4.5\sigma$ signal for the mass hierarchy from combining the muon and hadron
data.
| [
{
"created": "Thu, 6 Jun 2013 15:01:12 GMT",
"version": "v1"
}
] | 2015-06-16 | [
[
"Ghosh",
"Anushree",
""
],
[
"Choubey",
"Sandhya",
""
]
] | Neutrino mass hierarchy can be measured in atmospheric neutrino experiments through the observation of earth matter effects. Magnetized iron calorimeters have been shown to be good in this regard due to their charge identification capabilities. The charged current interaction of $\nu_\mu$ in this detector, produces a muon track and a hadron shower. The direction of the muon track can be measured very accurately. We show the improvement expected in the reach of this class of experiments to the neutrino mass hierarchy, as we improve the muon energy resolution and the muon reconstruction efficiency. We next propose to include the hadron events in the analysis, by tagging them with the zenith angle of the corresponding muon and binning the hadron data first in energy and then in zenith angle. To the best of our knowledge this way of performing the analysis of the atmospheric neutrino data has not be considered before. We show that the hadron events increase the mass hierarchy sensitivity of the experiment. Finally, we show the expected mass hierarchy sensitivity in terms of the reconstructed neutrino energy and zenith angle. We show how the detector resolutions spoil the earth matter effects in the neutrino channel and argue why the sensitivity obtained from the neutrino analysis cannot be significantly better than that obtained from the analysis using muon data alone. As a result, the best mass hierarchy sensitivity is obtained when we add the contribution of the muon and the hadron data. For $\sin^22\theta_{13}=0.1$, $\sin^2\theta_{23}=0.5$, a muon energy resolution of 2\%, reconstruction efficiency of 80\% and exposure of $50\times 10$ kton-year, we could get up to $4.5\sigma$ signal for the mass hierarchy from combining the muon and hadron data. |
2307.11813 | Yogev Shpilman | Nicol\'as Bernal, Marta Losada, Yosef Nir, Yogev Shpilman | The flavor of a light charged Higgs | 19 pages, 4 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The ATLAS Collaboration has recently reported a search for light-charged
Higgs in $t\to H^+ b$ decay, with $H^+\to c\bar b$. An excess with a local
significance of approximately $3\sigma$ is found at $m_{H^+}\approx130$ GeV,
with a best-fit value of ${\rm BR}(t\to H^+b)\times {\rm BR}(H^+\to c\bar
b)=(1.6\pm0.6)\times10^{-3}$. We study the implications of such a hypothetical
signal in multi-Higgs doublet models. We take into account constraints from
searches for other charged Higgs decays and from flavor-changing neutral
current processes. Two Higgs doublet models with flavor structure dictated by
natural flavor conservation (NFC), minimal flavor violation (MFV), or the
Froggatt-Nielsen (FN) mechanism cannot account for such excess. A three-Higgs
doublet model with NFC can account for the signal. The Yukawa couplings of the
neutral pseudoscalar $A$ in the down sector, $\hat Y_A^D$, should be larger by
a factor of $4-6$ compared to the corresponding Yukawa couplings of the Higgs
$h$, $\hat Y_h^D$. We further present two minimal scenarios, one in which a
single Yukawa coupling in the down sector, $(\hat Y_A^D)_{bb}$, gives the only
significant contribution, and one in which two Yukawa couplings in the up
sector, $(\hat Y_A^U)_{tt}$ and $(\hat Y_A^U)_{tc}$, give the only significant
contributions, and we discuss possible tests of these scenarios.
| [
{
"created": "Fri, 21 Jul 2023 18:00:01 GMT",
"version": "v1"
},
{
"created": "Wed, 11 Oct 2023 22:06:08 GMT",
"version": "v2"
}
] | 2023-10-13 | [
[
"Bernal",
"Nicolás",
""
],
[
"Losada",
"Marta",
""
],
[
"Nir",
"Yosef",
""
],
[
"Shpilman",
"Yogev",
""
]
] | The ATLAS Collaboration has recently reported a search for light-charged Higgs in $t\to H^+ b$ decay, with $H^+\to c\bar b$. An excess with a local significance of approximately $3\sigma$ is found at $m_{H^+}\approx130$ GeV, with a best-fit value of ${\rm BR}(t\to H^+b)\times {\rm BR}(H^+\to c\bar b)=(1.6\pm0.6)\times10^{-3}$. We study the implications of such a hypothetical signal in multi-Higgs doublet models. We take into account constraints from searches for other charged Higgs decays and from flavor-changing neutral current processes. Two Higgs doublet models with flavor structure dictated by natural flavor conservation (NFC), minimal flavor violation (MFV), or the Froggatt-Nielsen (FN) mechanism cannot account for such excess. A three-Higgs doublet model with NFC can account for the signal. The Yukawa couplings of the neutral pseudoscalar $A$ in the down sector, $\hat Y_A^D$, should be larger by a factor of $4-6$ compared to the corresponding Yukawa couplings of the Higgs $h$, $\hat Y_h^D$. We further present two minimal scenarios, one in which a single Yukawa coupling in the down sector, $(\hat Y_A^D)_{bb}$, gives the only significant contribution, and one in which two Yukawa couplings in the up sector, $(\hat Y_A^U)_{tt}$ and $(\hat Y_A^U)_{tc}$, give the only significant contributions, and we discuss possible tests of these scenarios. |
hep-ph/9705315 | Beatriz de Carlos | B. de Carlos (Sussex) and J.R. Espinosa (UPenn) | Cold Dark Matter Candidate in a Class of Supersymmetric Models with an
Extra U(1) | 13 pages, LaTex, uses psfig.sty with 3 figures | Phys.Lett. B407 (1997) 12-21 | 10.1016/S0370-2693(97)00747-8 | SUSX-TH-97-008, UPR-0749-T, IEM-FT-156/97 | hep-ph | null | In supersymmetric models whose gauge group includes an additional U(1) factor
at the TeV scale, broken by the VEV of an standard model singlet S, the
parameter space can accommodate a very light neutralino not ruled out
experimentally. This higgsino-like fermion, stable if R-parity is conserved,
can make a good cold dark matter candidate. We examine the thermal relic
density of this particle and discuss the prospects for its direct detection if
it forms part of our galactic halo.
| [
{
"created": "Wed, 14 May 1997 19:36:53 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"de Carlos",
"B.",
"",
"Sussex"
],
[
"Espinosa",
"J. R.",
"",
"UPenn"
]
] | In supersymmetric models whose gauge group includes an additional U(1) factor at the TeV scale, broken by the VEV of an standard model singlet S, the parameter space can accommodate a very light neutralino not ruled out experimentally. This higgsino-like fermion, stable if R-parity is conserved, can make a good cold dark matter candidate. We examine the thermal relic density of this particle and discuss the prospects for its direct detection if it forms part of our galactic halo. |
1901.07453 | Yuri V. Kovchegov | Yuri V. Kovchegov | Orbital Angular Momentum at Small $x$ | 27 pages | null | 10.1007/JHEP03(2019)174 | INT pre-print number INT-PUB-18-065 | hep-ph nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We determine the small Bjorken $x$ asymptotics of the quark and gluon orbital
angular momentum (OAM) distributions in the proton in the double-logarithmic
approximation (DLA), which resums powers of $\alpha_s \ln^2 (1/x)$ with
$\alpha_s$ the strong coupling constant. Starting with the operator definitions
for the quark and gluon OAM, we simplify them at small $x$, relating them,
respectively, to the polarized dipole amplitudes for the quark and gluon
helicities defined in our earlier works. Using the small-$x$ evolution
equations derived for these polarized dipole amplitudes earlier we arrive at
the following small-$x$ asymptotics of the quark and gluon OAM distributions in
the large-$N_c$ limit:
\begin{align}
L_{q + \bar{q}} (x, Q^2) = - \Delta \Sigma (x, Q^2) \sim
\left(\frac{1}{x}\right)^{\frac{4}{\sqrt{3}} \, \sqrt{\frac{\alpha_s
\, N_c}{2 \pi}} }, \ \ \ \ \
L_G (x, Q^2) \sim \Delta G (x, Q^2) \sim
\left(\frac{1}{x}\right)^{\frac{13}{4 \sqrt{3}} \, \sqrt{\frac{\alpha_s
\, N_c}{2 \pi}}} . \end{align}
| [
{
"created": "Tue, 22 Jan 2019 16:45:55 GMT",
"version": "v1"
}
] | 2019-05-01 | [
[
"Kovchegov",
"Yuri V.",
""
]
] | We determine the small Bjorken $x$ asymptotics of the quark and gluon orbital angular momentum (OAM) distributions in the proton in the double-logarithmic approximation (DLA), which resums powers of $\alpha_s \ln^2 (1/x)$ with $\alpha_s$ the strong coupling constant. Starting with the operator definitions for the quark and gluon OAM, we simplify them at small $x$, relating them, respectively, to the polarized dipole amplitudes for the quark and gluon helicities defined in our earlier works. Using the small-$x$ evolution equations derived for these polarized dipole amplitudes earlier we arrive at the following small-$x$ asymptotics of the quark and gluon OAM distributions in the large-$N_c$ limit: \begin{align} L_{q + \bar{q}} (x, Q^2) = - \Delta \Sigma (x, Q^2) \sim \left(\frac{1}{x}\right)^{\frac{4}{\sqrt{3}} \, \sqrt{\frac{\alpha_s \, N_c}{2 \pi}} }, \ \ \ \ \ L_G (x, Q^2) \sim \Delta G (x, Q^2) \sim \left(\frac{1}{x}\right)^{\frac{13}{4 \sqrt{3}} \, \sqrt{\frac{\alpha_s \, N_c}{2 \pi}}} . \end{align} |
0710.2067 | Farvah Mahmoudi | F. Mahmoudi | SuperIso: A program for calculating the isospin asymmetry of B -> K*
gamma in the MSSM | 17 pages, 1 figure, source code can be obtained from
http://www3.tsl.uu.se/~nazila/superiso/ | Comput.Phys.Commun.178:745-754,2008 | 10.1016/j.cpc.2007.12.006 | null | hep-ph | null | We present a program for calculating the isospin symmetry breaking of the B
-> K* gamma decay in the MSSM with minimal flavor violation. This program
calculates the NLO supersymmetric contributions to the isospin asymmetry, using
the effective Hamiltonian approach and within the QCD factorization method. We
show that isospin symmetry breaking proves to be a very restrictive observable,
in particular in the mSUGRA parameter space. The program also calculates the
inclusive branching ratio associated to b -> s gamma transition, as a
comparison reference.
| [
{
"created": "Wed, 10 Oct 2007 17:09:39 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Mahmoudi",
"F.",
""
]
] | We present a program for calculating the isospin symmetry breaking of the B -> K* gamma decay in the MSSM with minimal flavor violation. This program calculates the NLO supersymmetric contributions to the isospin asymmetry, using the effective Hamiltonian approach and within the QCD factorization method. We show that isospin symmetry breaking proves to be a very restrictive observable, in particular in the mSUGRA parameter space. The program also calculates the inclusive branching ratio associated to b -> s gamma transition, as a comparison reference. |
1606.04943 | David McKeen | Brian Batell, Nicholas Lange, David McKeen, Maxim Pospelov, Adam Ritz | The Leptonic Higgs Portal | 10 pages, 5 figures | Phys. Rev. D 95, 075003 (2017) | 10.1103/PhysRevD.95.075003 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | An extended Higgs sector may allow for new scalar particles well below the
weak scale. In this work, we present a detailed study of a light scalar $S$
with enhanced coupling to leptons, which could be responsible for the existing
discrepancy between experimental and theoretical determinations of the muon
anomalous magnetic moment. We present an ultraviolet completion of this model
in terms of the lepton-specific two-Higgs doublet model and an additional
scalar singlet. We then analyze a plethora of experimental constraints on the
universal low energy model, and this UV completion, along with the sensitivity
reach at future experiments. The most relevant constraints originate from muon
and kaon decays, electron beam dump experiments, electroweak precision
observables, rare $B_d$ and $B_s$ decays and Higgs branching fractions. The
properties of the leptonic Higgs portal imply an enhanced couplings to heavy
leptons, and we identify the most promising search mode for the high-luminosity
electron-positron colliders as $e^+{+}e^-\to\tau^+{+}\tau^-{+}S \to
\tau^+{+}\tau^-{+}\ell{+}\bar \ell$, where $\ell =e,\mu$. Future analyses of
existing data from BaBar and Belle, and from the upcoming Belle II experiment,
will enable tests of this model as a putative solution to the muon $g-2$
problem for $m_S < 3.5$ GeV.
| [
{
"created": "Wed, 15 Jun 2016 20:00:01 GMT",
"version": "v1"
}
] | 2017-04-12 | [
[
"Batell",
"Brian",
""
],
[
"Lange",
"Nicholas",
""
],
[
"McKeen",
"David",
""
],
[
"Pospelov",
"Maxim",
""
],
[
"Ritz",
"Adam",
""
]
] | An extended Higgs sector may allow for new scalar particles well below the weak scale. In this work, we present a detailed study of a light scalar $S$ with enhanced coupling to leptons, which could be responsible for the existing discrepancy between experimental and theoretical determinations of the muon anomalous magnetic moment. We present an ultraviolet completion of this model in terms of the lepton-specific two-Higgs doublet model and an additional scalar singlet. We then analyze a plethora of experimental constraints on the universal low energy model, and this UV completion, along with the sensitivity reach at future experiments. The most relevant constraints originate from muon and kaon decays, electron beam dump experiments, electroweak precision observables, rare $B_d$ and $B_s$ decays and Higgs branching fractions. The properties of the leptonic Higgs portal imply an enhanced couplings to heavy leptons, and we identify the most promising search mode for the high-luminosity electron-positron colliders as $e^+{+}e^-\to\tau^+{+}\tau^-{+}S \to \tau^+{+}\tau^-{+}\ell{+}\bar \ell$, where $\ell =e,\mu$. Future analyses of existing data from BaBar and Belle, and from the upcoming Belle II experiment, will enable tests of this model as a putative solution to the muon $g-2$ problem for $m_S < 3.5$ GeV. |
hep-ph/0201189 | Thomas Schaefer | Thomas Schaefer (Duke U, SUNY Stony Brook and Riken-BNL) | Instanton Effects in QCD at High Baryon Density | 27 pages, 8 figures, minor revisions | Phys.Rev. D65 (2002) 094033 | 10.1103/PhysRevD.65.094033 | null | hep-ph hep-lat | null | We study instanton effects in QCD at very high baryon density. In this regime
instantons are suppressed by a large power of $(\Lambda_{QCD}/\mu)$, where
$\Lambda_{QCD}$ is the QCD scale parameter and $\mu$ is the baryon chemical
potential. Instantons are nevertheless important because they contribute to
several physical observables that vanish to all orders in perturbative QCD. We
study, in particular, the chiral condensate and its contribution $m_{GB}^2\sim
m<\bar{\psi}\psi>$ to the masses of Goldstone bosons in the CFL phase of QCD
with $N_f=3$ flavors. We find that at densities $\rho\sim (5-10) \rho_0$, where
$\rho_0$ is the density of nuclear matter, the result is dominated by large
instantons and subject to considerable uncertainties. We suggest that these
uncertainties can be addressed using lattice calculations of the instanton
density and the pseudoscalar diquark mass in QCD with two colors. We study the
topological susceptibility and Witten-Veneziano type mass relations in both
$N_c=2$ and $N_c=3$ QCD.
| [
{
"created": "Mon, 21 Jan 2002 19:16:45 GMT",
"version": "v1"
},
{
"created": "Sat, 9 Feb 2002 19:54:40 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Schaefer",
"Thomas",
"",
"Duke U, SUNY Stony Brook and Riken-BNL"
]
] | We study instanton effects in QCD at very high baryon density. In this regime instantons are suppressed by a large power of $(\Lambda_{QCD}/\mu)$, where $\Lambda_{QCD}$ is the QCD scale parameter and $\mu$ is the baryon chemical potential. Instantons are nevertheless important because they contribute to several physical observables that vanish to all orders in perturbative QCD. We study, in particular, the chiral condensate and its contribution $m_{GB}^2\sim m<\bar{\psi}\psi>$ to the masses of Goldstone bosons in the CFL phase of QCD with $N_f=3$ flavors. We find that at densities $\rho\sim (5-10) \rho_0$, where $\rho_0$ is the density of nuclear matter, the result is dominated by large instantons and subject to considerable uncertainties. We suggest that these uncertainties can be addressed using lattice calculations of the instanton density and the pseudoscalar diquark mass in QCD with two colors. We study the topological susceptibility and Witten-Veneziano type mass relations in both $N_c=2$ and $N_c=3$ QCD. |
hep-ph/0411214 | Samuel Friot | Samuel Friot (LM-Orsay, CPT) | The L-R Correlator and its Chiral Condensates in the MHA and MHA+V'
Approximations to Large-Nc QCD | null | null | null | null | hep-ph | null | In this talk, we describe part of a recent work on the correlation function
of a V-A current with a V+A current in the framework of QCD in the limit of a
large number of colours Nc. The discussion takes place within two successive
approximations of this theory, called MHA and MHA+V'. Results concerning the
evaluation of chiral condensates of dimension six and eight, as well as matrix
elements of the Q7 and Q8 electroweak penguin operators, are given.
| [
{
"created": "Tue, 16 Nov 2004 20:38:41 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Friot",
"Samuel",
"",
"LM-Orsay, CPT"
]
] | In this talk, we describe part of a recent work on the correlation function of a V-A current with a V+A current in the framework of QCD in the limit of a large number of colours Nc. The discussion takes place within two successive approximations of this theory, called MHA and MHA+V'. Results concerning the evaluation of chiral condensates of dimension six and eight, as well as matrix elements of the Q7 and Q8 electroweak penguin operators, are given. |
0709.4641 | Georg Raffelt | Georg G. Raffelt, Alexei Yu. Smirnov | Adiabaticity and spectral splits in collective neutrino transformations | 20 pages, revtex, 13 figures | Phys.Rev.D76:125008,2007 | 10.1103/PhysRevD.76.125008 | MPP-2007-120 | hep-ph | null | Neutrinos streaming off a supernova core transform collectively by
neutrino-neutrino interactions, leading to "spectral splits" where an energy
E_split divides the transformed spectrum sharply into parts of almost pure but
different flavors. We present a detailed description of the spectral split
phenomenon which is conceptually and quantitatively understood in an adiabatic
treatment of neutrino-neutrino effects. Central to this theory is a
self-consistency condition in the form of two sum rules (integrals over the
neutrino spectra that must equal certain conserved quantities). We provide
explicit analytic and numerical solutions for various neutrino spectra. We
introduce the concept of the adiabatic reference frame and elaborate on the
relative adiabatic evolution. Violating adiabaticity leads to the spectral
split being "washed out". The sharpness of the split appears to be represented
by a surprisingly universal function.
| [
{
"created": "Fri, 28 Sep 2007 15:58:38 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Raffelt",
"Georg G.",
""
],
[
"Smirnov",
"Alexei Yu.",
""
]
] | Neutrinos streaming off a supernova core transform collectively by neutrino-neutrino interactions, leading to "spectral splits" where an energy E_split divides the transformed spectrum sharply into parts of almost pure but different flavors. We present a detailed description of the spectral split phenomenon which is conceptually and quantitatively understood in an adiabatic treatment of neutrino-neutrino effects. Central to this theory is a self-consistency condition in the form of two sum rules (integrals over the neutrino spectra that must equal certain conserved quantities). We provide explicit analytic and numerical solutions for various neutrino spectra. We introduce the concept of the adiabatic reference frame and elaborate on the relative adiabatic evolution. Violating adiabaticity leads to the spectral split being "washed out". The sharpness of the split appears to be represented by a surprisingly universal function. |
1606.01302 | Konstantin Goulianos | K. Goulianos | RENORM tensor-Pomeron diffractive predictions | 4 pages, 1 figure, 1 table. Talk at Rencontres de Moriond QCD and
High Energy Interactions, La Thuile, Italy, March 19-26, 2016. Misprints
corrected in Table~1 and in text (pg 3 par 2 line 7) | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Predictions of the elastic scattering, total-inetastic, and total
proton-proton cross sections, based on a Regge theory inspired tensor-Pomeron
implementation of the RENORM model for hadronic diffraction, are compared to
the latest experimental measurements at the LHC. The measured cross sections
are in good agreement within the experimental uncertainties of the data and the
theoretical uncertainties of the model, reaching down to the ~1% level.
| [
{
"created": "Fri, 3 Jun 2016 23:20:00 GMT",
"version": "v1"
},
{
"created": "Fri, 23 Sep 2016 18:35:42 GMT",
"version": "v2"
},
{
"created": "Mon, 26 Sep 2016 19:16:06 GMT",
"version": "v3"
}
] | 2016-09-27 | [
[
"Goulianos",
"K.",
""
]
] | Predictions of the elastic scattering, total-inetastic, and total proton-proton cross sections, based on a Regge theory inspired tensor-Pomeron implementation of the RENORM model for hadronic diffraction, are compared to the latest experimental measurements at the LHC. The measured cross sections are in good agreement within the experimental uncertainties of the data and the theoretical uncertainties of the model, reaching down to the ~1% level. |
0708.3884 | Raymond R. Volkas | Raymond R. Volkas | A domain-wall-brane-localized standard model | 4 pages, 2 figures. Talk at PASCOS07, to appear in the proceedings | AIPConf.Proc.957:279-282,2007 | 10.1063/1.2823780 | null | hep-ph | null | We sketch an SU(5) bulk model in 4+1-dimensions that plausibly produces an
effective 3+1-dimensional standard model dynamically-localized on a domain
wall.
| [
{
"created": "Wed, 29 Aug 2007 04:54:20 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Volkas",
"Raymond R.",
""
]
] | We sketch an SU(5) bulk model in 4+1-dimensions that plausibly produces an effective 3+1-dimensional standard model dynamically-localized on a domain wall. |
2101.10956 | Manas Mohapatra | Manas K. Mohapatra (IIT Hyderabad, Kandi) | Scrutinizing new physics of $B_d\to \phi (\eta^{(')},\pi, \omega)$ decay
modes | 25 pages, 5 figures | null | 10.1088/1361-6471/abe8cb | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | We inspect the exclusive hadronic decay modes $ B_d\to \phi (\eta^{(')}, \pi,
\omega)$, induced by quark level transition as $b\to d$ $(\Delta S=0)$, in
vector like down quark model. As these decay modes insist highly suppressed
followed by the predicted branching fraction $\mathcal{O}(10^{-9})$ which
reflects to scrutinize physics beyond the standard model. We constrain the new
parameter space inferred from experimental limits on leptonic $B_d\to \ell
\ell(\ell=e, \mu, \tau)$ and nonleptonic decay modes $B_d \to \eta' \pi^0$ and
$B_u\to \rho^- \eta'$. We then check the new physics contributions can have
significant impact on the prominent observable so called branching ratio of
$B_d\to \phi (\eta^{(')},\pi, \omega)$ processes.
| [
{
"created": "Tue, 26 Jan 2021 17:29:12 GMT",
"version": "v1"
}
] | 2021-05-26 | [
[
"Mohapatra",
"Manas K.",
"",
"IIT Hyderabad, Kandi"
]
] | We inspect the exclusive hadronic decay modes $ B_d\to \phi (\eta^{(')}, \pi, \omega)$, induced by quark level transition as $b\to d$ $(\Delta S=0)$, in vector like down quark model. As these decay modes insist highly suppressed followed by the predicted branching fraction $\mathcal{O}(10^{-9})$ which reflects to scrutinize physics beyond the standard model. We constrain the new parameter space inferred from experimental limits on leptonic $B_d\to \ell \ell(\ell=e, \mu, \tau)$ and nonleptonic decay modes $B_d \to \eta' \pi^0$ and $B_u\to \rho^- \eta'$. We then check the new physics contributions can have significant impact on the prominent observable so called branching ratio of $B_d\to \phi (\eta^{(')},\pi, \omega)$ processes. |
1602.03464 | Tsuguo Mogami | Tsuguo Mogami | A Classical Solution of Massive Yang-Mills Fields | 6 pages, 1 figure | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recent researches on the solution of Schwinger-Dyson equations, as well as
lattice simulations of pure QCD, suggest that the gluon propagator is massive.
In this letter, we assume that the classical counterpart of this massive gluon
field may be represented with the equation of motion for Yang-Mills theory with
a mass term added. A new classical solution is given for this equation. It is
discussed that this solution may have some role in confinement.
| [
{
"created": "Thu, 5 Nov 2015 21:02:18 GMT",
"version": "v1"
}
] | 2016-02-11 | [
[
"Mogami",
"Tsuguo",
""
]
] | Recent researches on the solution of Schwinger-Dyson equations, as well as lattice simulations of pure QCD, suggest that the gluon propagator is massive. In this letter, we assume that the classical counterpart of this massive gluon field may be represented with the equation of motion for Yang-Mills theory with a mass term added. A new classical solution is given for this equation. It is discussed that this solution may have some role in confinement. |
1705.00141 | Feng-Kun Guo | Feng-Kun Guo, Christoph Hanhart, Ulf-G. Mei{\ss}ner, Qian Wang, Qiang
Zhao, Bing-Song Zou | Hadronic molecules | Corrected several entries in Table VI for the contact terms for the
S-wave interactions between the spin multiplets of D1 and Dbar; 67 pages, 23
figures | Rev. Mod. Phys. 90, 015004 (2018) | 10.1103/RevModPhys.90.015004 | null | hep-ph hep-ex hep-lat nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A large number of experimental discoveries especially in the heavy quarkonium
sector that did not at all fit to the expectations of the until then very
successful quark model led to a renaissance of hadron spectroscopy. Among
various explanations of the internal structure of these excitations, hadronic
molecules, being analogues of light nuclei, play a unique role since for those
predictions can be made with controlled uncertainty. We review experimental
evidences of various candidates of hadronic molecules, and methods of
identifying such structures. Nonrelativistic effective field theories are the
suitable framework for studying hadronic molecules, and are discussed in both
the continuum and finite volumes. Also pertinent lattice QCD results are
presented. Further, we discuss the production mechanisms and decays of hadronic
molecules, and comment on the reliability of certain assertions often made in
the literature.
| [
{
"created": "Sat, 29 Apr 2017 07:16:55 GMT",
"version": "v1"
},
{
"created": "Wed, 27 Sep 2017 19:43:08 GMT",
"version": "v2"
},
{
"created": "Sat, 16 Apr 2022 09:01:23 GMT",
"version": "v3"
}
] | 2022-04-21 | [
[
"Guo",
"Feng-Kun",
""
],
[
"Hanhart",
"Christoph",
""
],
[
"Meißner",
"Ulf-G.",
""
],
[
"Wang",
"Qian",
""
],
[
"Zhao",
"Qiang",
""
],
[
"Zou",
"Bing-Song",
""
]
] | A large number of experimental discoveries especially in the heavy quarkonium sector that did not at all fit to the expectations of the until then very successful quark model led to a renaissance of hadron spectroscopy. Among various explanations of the internal structure of these excitations, hadronic molecules, being analogues of light nuclei, play a unique role since for those predictions can be made with controlled uncertainty. We review experimental evidences of various candidates of hadronic molecules, and methods of identifying such structures. Nonrelativistic effective field theories are the suitable framework for studying hadronic molecules, and are discussed in both the continuum and finite volumes. Also pertinent lattice QCD results are presented. Further, we discuss the production mechanisms and decays of hadronic molecules, and comment on the reliability of certain assertions often made in the literature. |
hep-ph/9401282 | null | R.F. Alvarez-Estrada, A. Dobado and A. Gomez Nicola (Departamento
Fisica Teorica U.C.M., Madrid, Spain) | One loop calculations on the Wess-Zumino-Witten anomalous functional at
finite temperature | Latex, 13 pages and 3 figures avalaible upon request | Phys.Lett. B324 (1994) 345-350 | 10.1016/0370-2693(94)90204-6 | FT/UCM/15/93 | hep-ph | null | We analyze the finite temperature (T) extension of the Wess-Zumino- Witten
functional, discussed in a previous work, to one loop in chiral perturbation
theory. As a phenomenological application, we calculate finite temperature
corrections to the amplitude of the $\pi^0$ decay into two photons. This
calculation is performed in three limits : i)$T/M_{\pi}<<1$, ii)the chiral
limit at finite T and iii)$T/M_{\pi}>>1$ ($M_{\pi}$ being the pion mass). The
$T$-corrections tend to vanish in the chiral limit, where only the kaon
contribution remains (although it is exponentially suppressed).
| [
{
"created": "Wed, 19 Jan 1994 11:14:21 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Alvarez-Estrada",
"R. F.",
"",
"Departamento\n Fisica Teorica U.C.M., Madrid, Spain"
],
[
"Dobado",
"A.",
"",
"Departamento\n Fisica Teorica U.C.M., Madrid, Spain"
],
[
"Nicola",
"A. Gomez",
"",
"Departamento\n Fisica Teorica U.C.M., Madrid, Spain"
]
] | We analyze the finite temperature (T) extension of the Wess-Zumino- Witten functional, discussed in a previous work, to one loop in chiral perturbation theory. As a phenomenological application, we calculate finite temperature corrections to the amplitude of the $\pi^0$ decay into two photons. This calculation is performed in three limits : i)$T/M_{\pi}<<1$, ii)the chiral limit at finite T and iii)$T/M_{\pi}>>1$ ($M_{\pi}$ being the pion mass). The $T$-corrections tend to vanish in the chiral limit, where only the kaon contribution remains (although it is exponentially suppressed). |
hep-ph/9605279 | V. Belyaev | V.M. Belyaev and Mikkel B. Johnson | Deep Inelastic Scattering and Light-Cone Wave Functions | 7 pages, LaTeX, macros - sprocl.sty, epsfig.sty, 1 figure
Contribution to the Workshop "Continuous Advances in QCD, '96", March 28-31,
1996, Minneapolis, Minnesota | null | null | null | hep-ph | null | In the framework of light-cone QCD sum rules, we study the valence quark
distribution function $q(x_B)$ of a pion for moderate $x_B$. The sum rule with
the leading twist-2 wave function gives $q(x_B)=\varphi_\pi(x_B)$. Twist-4 wave
functions give about 30\% for $x_B\sim 0.5$. It is shown that QCD sum rule
predictions, with the asymptotic pion wave function, are in good agreement with
experimental data. We found that a two-hump profile for the twist-2 wave
function leads to a valence quark disribution function that contradicts
experimental data.
| [
{
"created": "Sat, 11 May 1996 00:16:43 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Belyaev",
"V. M.",
""
],
[
"Johnson",
"Mikkel B.",
""
]
] | In the framework of light-cone QCD sum rules, we study the valence quark distribution function $q(x_B)$ of a pion for moderate $x_B$. The sum rule with the leading twist-2 wave function gives $q(x_B)=\varphi_\pi(x_B)$. Twist-4 wave functions give about 30\% for $x_B\sim 0.5$. It is shown that QCD sum rule predictions, with the asymptotic pion wave function, are in good agreement with experimental data. We found that a two-hump profile for the twist-2 wave function leads to a valence quark disribution function that contradicts experimental data. |
1111.5857 | Simon Knapen | Simon Knapen, Yue Zhao and Matthew J. Strassler | Diagnosing the top-quark angular asymmetry using LHC intrinsic charge
asymmetries | null | null | 10.1103/PhysRevD.86.014013 | RUNHETC-2011-23 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Flavor-violating interactions involving new heavy particles are among
proposed explanations for the $t\bar t$ forward-backward asymmetry observed at
the Tevatron. Many of these models generate a $t\bar t$-plus-jet signal at the
LHC. In this paper we identify several new charge asymmetric variables in
$t\bar tj$ events that can contribute to the discovery of such models at the
LHC. We propose a data-driven method for the background, largely eliminating
the need for a Monte Carlo prediction of $t\bar t$-plus-jets, and thus reducing
systematic errors. With a fast detector simulation, we estimate the statistical
sensitivity of our variables for one of these models, finding that
charge-asymmetric variables could materially assist in the exclusion of the
Standard Model across much of the mass and coupling range, given 5 inverse fb
of data. Should any signal appear, our variables will be useful in
distinguishing classes of models from one another.
| [
{
"created": "Thu, 24 Nov 2011 21:42:52 GMT",
"version": "v1"
}
] | 2013-05-30 | [
[
"Knapen",
"Simon",
""
],
[
"Zhao",
"Yue",
""
],
[
"Strassler",
"Matthew J.",
""
]
] | Flavor-violating interactions involving new heavy particles are among proposed explanations for the $t\bar t$ forward-backward asymmetry observed at the Tevatron. Many of these models generate a $t\bar t$-plus-jet signal at the LHC. In this paper we identify several new charge asymmetric variables in $t\bar tj$ events that can contribute to the discovery of such models at the LHC. We propose a data-driven method for the background, largely eliminating the need for a Monte Carlo prediction of $t\bar t$-plus-jets, and thus reducing systematic errors. With a fast detector simulation, we estimate the statistical sensitivity of our variables for one of these models, finding that charge-asymmetric variables could materially assist in the exclusion of the Standard Model across much of the mass and coupling range, given 5 inverse fb of data. Should any signal appear, our variables will be useful in distinguishing classes of models from one another. |
2408.06325 | Piotr Bargiela DPhil | Piotr Bargiela, Tong-Zhi Yang | On the finite basis topologies for multi-loop high-multiplicity Feynman
integrals | 10 pages, 2 figures, 2 tables | null | null | ZU-TH 41/24 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we systematically analyse Feynman integrals in the `t
Hooft-Veltman scheme. We write an explicit reduction resulting from partial
fractioning the high-multiplicity integrands to a finite basis of topologies at
any given loop order. We find all of these finite basis topologies at two loops
in four external dimensions. Their maximal cut and the leading singularity are
expressed in terms of the Gram determinant and Baikov polynomial. By performing
an Integration-By-Parts reduction without any cut constraint on a numerical
probe for one of these topologies, we show that the computational complexity
drops significantly compared to the Conventional Dimensional Regularization
scheme. Formally, our work implies an upper bound on the rigidity of special
functions appearing in the iterated integral solutions at each loop order in
perturbative Quantum Field Theory. Phenomenologically, the integrand-level
reduction we present will substantially simplify the task of providing
high-precision predictions for future high-multiplicity collider observables.
| [
{
"created": "Mon, 12 Aug 2024 17:44:01 GMT",
"version": "v1"
}
] | 2024-08-13 | [
[
"Bargiela",
"Piotr",
""
],
[
"Yang",
"Tong-Zhi",
""
]
] | In this work, we systematically analyse Feynman integrals in the `t Hooft-Veltman scheme. We write an explicit reduction resulting from partial fractioning the high-multiplicity integrands to a finite basis of topologies at any given loop order. We find all of these finite basis topologies at two loops in four external dimensions. Their maximal cut and the leading singularity are expressed in terms of the Gram determinant and Baikov polynomial. By performing an Integration-By-Parts reduction without any cut constraint on a numerical probe for one of these topologies, we show that the computational complexity drops significantly compared to the Conventional Dimensional Regularization scheme. Formally, our work implies an upper bound on the rigidity of special functions appearing in the iterated integral solutions at each loop order in perturbative Quantum Field Theory. Phenomenologically, the integrand-level reduction we present will substantially simplify the task of providing high-precision predictions for future high-multiplicity collider observables. |
1602.02790 | Go Mishima | Go Mishima, Yukinari Sumino, Hiromasa Takaura | UV contribution and power dependence on $\Lambda_\mathrm{QCD}$ of Adler
function | 10 pages, 5 figures. v3: minor modifications | PLB 759 (2016) 550 | 10.1016/j.physletb.2016.06.010 | UT-16-06, TU-1016 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We formulate a way to separate UV and IR contributions to the Adler function
and discuss how $\Lambda_\mathrm{QCD}^2/Q^2$ dependence is encoded in the UV
contribution within perturbative QCD.
| [
{
"created": "Mon, 8 Feb 2016 21:25:10 GMT",
"version": "v1"
},
{
"created": "Fri, 22 Apr 2016 06:23:33 GMT",
"version": "v2"
},
{
"created": "Mon, 27 Jun 2016 05:36:18 GMT",
"version": "v3"
}
] | 2016-06-28 | [
[
"Mishima",
"Go",
""
],
[
"Sumino",
"Yukinari",
""
],
[
"Takaura",
"Hiromasa",
""
]
] | We formulate a way to separate UV and IR contributions to the Adler function and discuss how $\Lambda_\mathrm{QCD}^2/Q^2$ dependence is encoded in the UV contribution within perturbative QCD. |
1704.05849 | John Gargalionis | Yi Cai, John Gargalionis, Michael A. Schmidt and Raymond R. Volkas | Reconsidering the One Leptoquark solution: flavor anomalies and neutrino
mass | 43 pages, 17 figures, 3 tables; corrected fit contours in fig. 12 | null | 10.1007/JHEP10(2017)047 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We reconsider a model introducing a scalar leptoquark $\phi \sim (\mathbf{3},
\mathbf{1}, -1/3)$ to explain recent deviations from the standard model in
semileptonic $B$ decays. The leptoquark can accommodate the persistent tension
in the decays $\bar{B}\rightarrow D^{(*)}\tau \bar{\nu}$ as long as its mass is
lower than approximately $10 \text{ TeV}$, and we show that a sizeable Yukawa
coupling to the right-chiral tau lepton is necessary for an acceptable
explanation. Agreement with the measured $\bar{B}\rightarrow D^{(*)}\tau
\bar{\nu}$ rates is mildly compromised for parameter choices addressing the
tensions in $b \to s \mu \mu$, where the model can significantly reduce the
discrepancies in angular observables, branching ratios and the
lepton-flavor-universality observables $R_K$ and $R_{K^*}$. The leptoquark can
also reconcile the predicted and measured value of the anomalous magnetic
moment of the muon and appears naturally in models of radiative neutrino mass
derived from lepton-number violating effective operators. As a representative
example, we incorporate the particle into an existing two-loop neutrino mass
scenario derived from a dimension-nine operator. In this specific model, the
structure of the neutrino mass matrix provides enough freedom to explain the
small masses of the neutrinos in the region of parameter space dictated by
agreement with the anomalies in $\bar{B}\rightarrow D^{(*)}\tau \bar{\nu}$, but
not the $b \to s$ transition. This is achieved without excessive fine-tuning in
the parameters important for neutrino mass.
| [
{
"created": "Wed, 19 Apr 2017 18:00:01 GMT",
"version": "v1"
},
{
"created": "Sun, 14 May 2017 04:45:59 GMT",
"version": "v2"
},
{
"created": "Tue, 20 Jun 2017 17:17:43 GMT",
"version": "v3"
}
] | 2017-10-25 | [
[
"Cai",
"Yi",
""
],
[
"Gargalionis",
"John",
""
],
[
"Schmidt",
"Michael A.",
""
],
[
"Volkas",
"Raymond R.",
""
]
] | We reconsider a model introducing a scalar leptoquark $\phi \sim (\mathbf{3}, \mathbf{1}, -1/3)$ to explain recent deviations from the standard model in semileptonic $B$ decays. The leptoquark can accommodate the persistent tension in the decays $\bar{B}\rightarrow D^{(*)}\tau \bar{\nu}$ as long as its mass is lower than approximately $10 \text{ TeV}$, and we show that a sizeable Yukawa coupling to the right-chiral tau lepton is necessary for an acceptable explanation. Agreement with the measured $\bar{B}\rightarrow D^{(*)}\tau \bar{\nu}$ rates is mildly compromised for parameter choices addressing the tensions in $b \to s \mu \mu$, where the model can significantly reduce the discrepancies in angular observables, branching ratios and the lepton-flavor-universality observables $R_K$ and $R_{K^*}$. The leptoquark can also reconcile the predicted and measured value of the anomalous magnetic moment of the muon and appears naturally in models of radiative neutrino mass derived from lepton-number violating effective operators. As a representative example, we incorporate the particle into an existing two-loop neutrino mass scenario derived from a dimension-nine operator. In this specific model, the structure of the neutrino mass matrix provides enough freedom to explain the small masses of the neutrinos in the region of parameter space dictated by agreement with the anomalies in $\bar{B}\rightarrow D^{(*)}\tau \bar{\nu}$, but not the $b \to s$ transition. This is achieved without excessive fine-tuning in the parameters important for neutrino mass. |
1511.06779 | Eric S. Swanson | R.A. Briceno, T.D. Cohen, S. Coito, J.J. Dudek, E. Eichten, C.S.
Fischer, M. Fritsch, W. Gradl, A. Jackura, M. Kornicer, G. Krein, R.F. Lebed,
F.A. Machado, R.E. Mitchell, C.J. Morningstar, M. Peardon, M.R. Pennington,
K. Peters, J.-M. Richard, C.-P. Shen, M.R. Shepherd, T. Skwarnicki, E.S.
Swanson, A.P. Szczepaniak, C.-Z. Yuan | Issues and Opportunities in Exotic Hadrons | White paper from INT workshop, "Modern Exotic Hadrons". References
added. Version to appear in Chinese Physics C | null | 10.1088/1674-1137/40/4/042001 | INT-PUB-15-066 | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The last few years have been witness to a proliferation of new results
concerning heavy exotic hadrons. Experimentally, many new signals have been
discovered that could be pointing towards the existence of tetraquarks,
pentaquarks, and other exotic configurations of quarks and gluons.
Theoretically, advances in lattice field theory techniques place us at the cusp
of understanding complex coupled-channel phenomena, modelling grows more
sophisticated, and effective field theories are being applied to an ever
greater range of situations. It is thus an opportune time to evaluate the
status of the field. In the following, a series of high priority experimental
and theoretical issues concerning heavy exotic hadrons is presented.
| [
{
"created": "Fri, 20 Nov 2015 21:33:48 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Mar 2016 19:55:10 GMT",
"version": "v2"
}
] | 2016-05-04 | [
[
"Briceno",
"R. A.",
""
],
[
"Cohen",
"T. D.",
""
],
[
"Coito",
"S.",
""
],
[
"Dudek",
"J. J.",
""
],
[
"Eichten",
"E.",
""
],
[
"Fischer",
"C. S.",
""
],
[
"Fritsch",
"M.",
""
],
[
"Gradl",
"W.",
""
],
[
"Jackura",
"A.",
""
],
[
"Kornicer",
"M.",
""
],
[
"Krein",
"G.",
""
],
[
"Lebed",
"R. F.",
""
],
[
"Machado",
"F. A.",
""
],
[
"Mitchell",
"R. E.",
""
],
[
"Morningstar",
"C. J.",
""
],
[
"Peardon",
"M.",
""
],
[
"Pennington",
"M. R.",
""
],
[
"Peters",
"K.",
""
],
[
"Richard",
"J. -M.",
""
],
[
"Shen",
"C. -P.",
""
],
[
"Shepherd",
"M. R.",
""
],
[
"Skwarnicki",
"T.",
""
],
[
"Swanson",
"E. S.",
""
],
[
"Szczepaniak",
"A. P.",
""
],
[
"Yuan",
"C. -Z.",
""
]
] | The last few years have been witness to a proliferation of new results concerning heavy exotic hadrons. Experimentally, many new signals have been discovered that could be pointing towards the existence of tetraquarks, pentaquarks, and other exotic configurations of quarks and gluons. Theoretically, advances in lattice field theory techniques place us at the cusp of understanding complex coupled-channel phenomena, modelling grows more sophisticated, and effective field theories are being applied to an ever greater range of situations. It is thus an opportune time to evaluate the status of the field. In the following, a series of high priority experimental and theoretical issues concerning heavy exotic hadrons is presented. |
1510.05186 | Yuta Hamada | Yuta Hamada, Kiyoharu Kawana | Reheating-era leptogenesis | 5 pages, 3 figures; published version(v2) | null | 10.1016/j.physletb.2016.10.067 | KUNS-2580 | hep-ph astro-ph.CO hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose a novel leptogenesis scenario at the reheating era. Our setup is
minimal in the sense that, in addition to the standard model Lagrangian, we
only consider an inflaton and higher dimensional operators. The lepton number
asymmetry is produced not by the decay of a heavy particle, but by the
scattering between the standard model particles. After the decay of an
inflaton, the model is described within the standard model with higher
dimensional operators. The Sakharov's three conditions are satisfied by the
following way. The violation of the lepton number is realized by the
dimension-5 operator. The complex phase comes from the dimension-6 four lepton
operator. The universe is out of equilibrium before the reheating is completed.
It is found that the successful baryogenesis is realized for the wide range of
parameters, the inflaton mass and reheating temperature, depending on the
cutoff scale. Since we only rely on the effective Lagrangian, our scenario can
be applicable to all mechanisms to generate neutrino Majorana masses.
| [
{
"created": "Sun, 18 Oct 2015 00:05:02 GMT",
"version": "v1"
},
{
"created": "Sat, 29 Oct 2016 03:20:37 GMT",
"version": "v2"
}
] | 2016-11-10 | [
[
"Hamada",
"Yuta",
""
],
[
"Kawana",
"Kiyoharu",
""
]
] | We propose a novel leptogenesis scenario at the reheating era. Our setup is minimal in the sense that, in addition to the standard model Lagrangian, we only consider an inflaton and higher dimensional operators. The lepton number asymmetry is produced not by the decay of a heavy particle, but by the scattering between the standard model particles. After the decay of an inflaton, the model is described within the standard model with higher dimensional operators. The Sakharov's three conditions are satisfied by the following way. The violation of the lepton number is realized by the dimension-5 operator. The complex phase comes from the dimension-6 four lepton operator. The universe is out of equilibrium before the reheating is completed. It is found that the successful baryogenesis is realized for the wide range of parameters, the inflaton mass and reheating temperature, depending on the cutoff scale. Since we only rely on the effective Lagrangian, our scenario can be applicable to all mechanisms to generate neutrino Majorana masses. |
1202.0367 | Pyungwon Ko | P. Ko (KIAS) | Effective field theory for top physics | To appear in Top 2011 Proceeding (Sant Feliu de Guixols, Spain) | null | 10.1393/ncc/i2012-11218-5 | KIAS Preprint P12004 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the top forward-backward asymmetry (FBA $\equiv A_{\rm FB}$)
reported by CDF and D0 Collaborations in the effective lagrangian approach.
Using dimension-6 effective largrangians for $q \bar{q} \rightarrow t \bar{t}$,
we study the $t\bar{t}$ production cross section and the $A_{\rm FB}$, and a
few observables: the FB spin-spin correlation that is strongly correlated with
the $A_{\rm FB}$, and longitudinal top polarization as a new probe of chiral
structures for possible new physics scenarios.
| [
{
"created": "Thu, 2 Feb 2012 05:49:44 GMT",
"version": "v1"
}
] | 2022-03-02 | [
[
"Ko",
"P.",
"",
"KIAS"
]
] | We study the top forward-backward asymmetry (FBA $\equiv A_{\rm FB}$) reported by CDF and D0 Collaborations in the effective lagrangian approach. Using dimension-6 effective largrangians for $q \bar{q} \rightarrow t \bar{t}$, we study the $t\bar{t}$ production cross section and the $A_{\rm FB}$, and a few observables: the FB spin-spin correlation that is strongly correlated with the $A_{\rm FB}$, and longitudinal top polarization as a new probe of chiral structures for possible new physics scenarios. |
2111.07738 | C. Q. Geng | C.Q. Geng, Chia-Wei Liu and Tien-Hsueh Tsai | Revisiting semileptonic $B^-\to p\bar{p} \ell^- \bar{\nu}_{\ell}$ decays | 15 pages, 5 figures | Phys. Rev. D104, 113002 (2021) | 10.1103/PhysRevD.104.113002 | null | hep-ph hep-ex | http://creativecommons.org/licenses/by/4.0/ | We systematically revisit the baryonic four-body semileptonic decays of $B^-
\to {\bf B}\bar{\bf B}'\ell^- \bar{\nu}_{\ell}$ by the perturbative QCD
counting rules with ${\bf B}$ representing octet baryons and $\ell=e,\mu$. We
study the transition form factors of $B^- \to {\bf B} \bar{\bf B}'$ in the
limit of $(p_{\bf B}+p_{\bar{\bf B}'})^2 \to \infty $ with the three-body
$\bar{B}\to {\bf B}\bar{\bf B}' M$ and $B^- \to p\bar{p} \mu^- \bar{\nu}_{\mu}$
data along with $SU(3)_f$ flavor symmetry. We calculate the decay branching
ratios and angular asymmetries as well as the differential decay branching
fractions of $B^- \to p \bar{p} \ell^- \bar{\nu}_{\ell}$. In particular, we
find that our new result of ${\cal B}( B^- \to p \bar{p} \ell^-
\bar{\nu}_{\ell})=(5.21\pm0.34)\times 10^{-6}$, which is about one order of
magnitude lower than the previous theoretical prediction of $(10.4\pm2.9)\times
10^{-5}$, agrees well with both experimental measurements of
$(5.8^{+2.6}_{-2.3})\times 10^{-6}$ and $(5.3\pm0.4)\times 10^{-6}$ by the
Belle and LHCb Collaborations, respectively. We also evaluate the branching
ratios and angular asymmetries in other channels of $B^- \to {\bf B}\bar{\bf
B}\ell^- \bar{\nu}_{\ell}$, which can be tested by the ongoing experiments at
LHCb and BelleII.
| [
{
"created": "Mon, 15 Nov 2021 13:39:54 GMT",
"version": "v1"
}
] | 2021-12-08 | [
[
"Geng",
"C. Q.",
""
],
[
"Liu",
"Chia-Wei",
""
],
[
"Tsai",
"Tien-Hsueh",
""
]
] | We systematically revisit the baryonic four-body semileptonic decays of $B^- \to {\bf B}\bar{\bf B}'\ell^- \bar{\nu}_{\ell}$ by the perturbative QCD counting rules with ${\bf B}$ representing octet baryons and $\ell=e,\mu$. We study the transition form factors of $B^- \to {\bf B} \bar{\bf B}'$ in the limit of $(p_{\bf B}+p_{\bar{\bf B}'})^2 \to \infty $ with the three-body $\bar{B}\to {\bf B}\bar{\bf B}' M$ and $B^- \to p\bar{p} \mu^- \bar{\nu}_{\mu}$ data along with $SU(3)_f$ flavor symmetry. We calculate the decay branching ratios and angular asymmetries as well as the differential decay branching fractions of $B^- \to p \bar{p} \ell^- \bar{\nu}_{\ell}$. In particular, we find that our new result of ${\cal B}( B^- \to p \bar{p} \ell^- \bar{\nu}_{\ell})=(5.21\pm0.34)\times 10^{-6}$, which is about one order of magnitude lower than the previous theoretical prediction of $(10.4\pm2.9)\times 10^{-5}$, agrees well with both experimental measurements of $(5.8^{+2.6}_{-2.3})\times 10^{-6}$ and $(5.3\pm0.4)\times 10^{-6}$ by the Belle and LHCb Collaborations, respectively. We also evaluate the branching ratios and angular asymmetries in other channels of $B^- \to {\bf B}\bar{\bf B}\ell^- \bar{\nu}_{\ell}$, which can be tested by the ongoing experiments at LHCb and BelleII. |
1802.06530 | Takeshi Fukuyama | Takeshi Fukuyama and Nobuchika Okada | Alternative renormalizable minimal SO(10) GUT and the Seesaw Scale | 12 pages, 1 figure, errors are corrected and references are added | null | 10.1142/S0217732318501675 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Alternative renormalizable minimal non-SUSY SO(10) GUT model is proposed.
Instead of a ${\bf 126}$-dimensional Higgs field, a ${\bf 120}$-dimensional
Higgs filed is ntroducedin addition to a ${\bf 10}$-dimensional Higgs field and
plays a crucial role to reproduce the realistic charged fermion mass matrices.
With contributions of ${\bf 120}$ Higgs field, the original Witten's scenario
of inducing the right-handed Majorana neutrino mass through 2-loop diagrams
becomes phenomenologically viable. This model inherits the nice features of the
conventional renormalizable minimal SO(10) GUT model with ${\bf 10}+{\bf
\overline{126}}$ Higgs fields, while supplemented with a low scale seesaw
mechanism due to the 2-loop induced right-handed Majorana neutrino mass.
%
| [
{
"created": "Mon, 19 Feb 2018 06:55:23 GMT",
"version": "v1"
},
{
"created": "Fri, 2 Mar 2018 15:13:33 GMT",
"version": "v2"
},
{
"created": "Mon, 23 Jul 2018 22:22:57 GMT",
"version": "v3"
}
] | 2018-10-17 | [
[
"Fukuyama",
"Takeshi",
""
],
[
"Okada",
"Nobuchika",
""
]
] | Alternative renormalizable minimal non-SUSY SO(10) GUT model is proposed. Instead of a ${\bf 126}$-dimensional Higgs field, a ${\bf 120}$-dimensional Higgs filed is ntroducedin addition to a ${\bf 10}$-dimensional Higgs field and plays a crucial role to reproduce the realistic charged fermion mass matrices. With contributions of ${\bf 120}$ Higgs field, the original Witten's scenario of inducing the right-handed Majorana neutrino mass through 2-loop diagrams becomes phenomenologically viable. This model inherits the nice features of the conventional renormalizable minimal SO(10) GUT model with ${\bf 10}+{\bf \overline{126}}$ Higgs fields, while supplemented with a low scale seesaw mechanism due to the 2-loop induced right-handed Majorana neutrino mass. % |
hep-ph/0609084 | Don Colladay | Don Colladay and Patrick McDonald | One-Loop Renormalization of Pure Yang-Mills with Lorentz Violation | 14 pages | Phys.Rev.D75:105002,2007 | 10.1103/PhysRevD.75.105002 | null | hep-ph | null | The explicit one-loop renormalizability of pure Yang-Mills theory with
Lorentz violation is demonstrated. The result is consistent with multiplicative
renormalization as the required counter terms are consistent with a single
re-scaling of the Lorentz-violation parameters. In addition, the resulting beta
functions indicate that the CPT-even Lorentz-violating terms increase with
energy scale in opposition to the asymptotically free gauge coupling and
CPT-odd terms. The calculations are performed at lowest-order in the
Lorentz-violating terms as they are assumed small.
| [
{
"created": "Fri, 8 Sep 2006 16:21:35 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Colladay",
"Don",
""
],
[
"McDonald",
"Patrick",
""
]
] | The explicit one-loop renormalizability of pure Yang-Mills theory with Lorentz violation is demonstrated. The result is consistent with multiplicative renormalization as the required counter terms are consistent with a single re-scaling of the Lorentz-violation parameters. In addition, the resulting beta functions indicate that the CPT-even Lorentz-violating terms increase with energy scale in opposition to the asymptotically free gauge coupling and CPT-odd terms. The calculations are performed at lowest-order in the Lorentz-violating terms as they are assumed small. |
hep-ph/0610407 | Jean-Philippe Lansberg | J.P. Lansberg, B. Pire, L. Szymanowski | Exploring backward pion electroproduction in the scaling regime | Presented at the 7th International Conference on Quark Confinement
and Hadron Spectrum (QCHS7), September 2-7 2006, Ponta Delgada, Portugal and
at Soft-Pions in hard processes, August 3-5 2006, Regensburg, Germany, 4
pages, LaTeX, uses aip-6s.clo, aipproc.cls and aipxfm.sty (included) | AIPConf.Proc.892:278-280,2007 | 10.1063/1.2714394 | null | hep-ph nucl-ex nucl-th | null | We use general relations between the Transition Distribution Amplitudes
(TDAs), entering the description of the p -> pi0 transition, and the proton
Distribution Amplitudes (DAs) in the soft-pion limit to estimate the size of
the amplitude for backward electroproduction of pi0 at large Q2.
| [
{
"created": "Mon, 30 Oct 2006 16:47:20 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Lansberg",
"J. P.",
""
],
[
"Pire",
"B.",
""
],
[
"Szymanowski",
"L.",
""
]
] | We use general relations between the Transition Distribution Amplitudes (TDAs), entering the description of the p -> pi0 transition, and the proton Distribution Amplitudes (DAs) in the soft-pion limit to estimate the size of the amplitude for backward electroproduction of pi0 at large Q2. |
0909.4016 | Andreas Krassnigg | A. Krassnigg | Survey of J=0,1 mesons in a Bethe-Salpeter approach | 8 pages, 4 figures | Phys.Rev.D80:114010,2009 | 10.1103/PhysRevD.80.114010 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Bethe-Salpeter equation is used to comprehensively study mesons with
J=0,1 and equal-mass constituents for quark masses from the chiral limit to the
b-quark mass. The survey contains masses of the ground states in all
corresponding J^{PC} channels including those with "exotic" quantum numbers.
The emphasis is put on each particular state's sensitivity to the low- and
intermediate-momentum, i.e., long-range part of the strong interaction.
| [
{
"created": "Tue, 22 Sep 2009 14:54:00 GMT",
"version": "v1"
}
] | 2009-12-30 | [
[
"Krassnigg",
"A.",
""
]
] | The Bethe-Salpeter equation is used to comprehensively study mesons with J=0,1 and equal-mass constituents for quark masses from the chiral limit to the b-quark mass. The survey contains masses of the ground states in all corresponding J^{PC} channels including those with "exotic" quantum numbers. The emphasis is put on each particular state's sensitivity to the low- and intermediate-momentum, i.e., long-range part of the strong interaction. |
1604.01665 | William John Murray | William Murray | The sensitivity of the Higgs boson branching ratios to the W boson width | 9 pages, 2 figures | Physics Letters B, 758, (2016), 98-100 | 10.1016/j.physletb.2016.04.056 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Higgs boson branching ratio into vector bosons is sensitive to the decay
widths of those vector bosons because they are produced with at least one boson
significantly off-shell. Gamma(H to V V ) is approximately proportional to the
product of the Higgs boson coupling and the vector boson width. Gamma Z is well
known, but Gamma W gives an uncertainty on Gamma(H to W W ) which is not
negligible. The ratio of branching ratios, BR(H to W W )/BR(H to ZZ) measured
by a combination of ATLAS and CMS at LHC is used herein to extract a width for
the W boson of Gamma W = 1.8+0.4-0.3 GeV by assuming Standard Model couplings
of the Higgs bosons. This dependence of the branching ratio on Gamma W is not
discussed in most Higgs boson coupling analyses.
| [
{
"created": "Wed, 6 Apr 2016 15:43:22 GMT",
"version": "v1"
}
] | 2016-05-10 | [
[
"Murray",
"William",
""
]
] | The Higgs boson branching ratio into vector bosons is sensitive to the decay widths of those vector bosons because they are produced with at least one boson significantly off-shell. Gamma(H to V V ) is approximately proportional to the product of the Higgs boson coupling and the vector boson width. Gamma Z is well known, but Gamma W gives an uncertainty on Gamma(H to W W ) which is not negligible. The ratio of branching ratios, BR(H to W W )/BR(H to ZZ) measured by a combination of ATLAS and CMS at LHC is used herein to extract a width for the W boson of Gamma W = 1.8+0.4-0.3 GeV by assuming Standard Model couplings of the Higgs bosons. This dependence of the branching ratio on Gamma W is not discussed in most Higgs boson coupling analyses. |
hep-ph/9311288 | Michael A. Doncheski | Michael A. Doncheski and Stephen Godfrey | Resolved Photon Contributions to Leptoquark Production in $e^+ e^-$ and
$e\gamma$ Collision | 9 pages (5 postscript figures in separate uuencoded file), OCIP/C
93-15 | Phys.Rev. D49 (1994) 6220-6223 | 10.1103/PhysRevD.49.6220 | null | hep-ph | null | We calculate the resolved photon contribution to leptoquark production at
$e\gamma$ colliders for the center of mass energies $\sqrt s=500$~GeV and
1~TeV. We also calculate the resolved photon contribution to leptoquark
production at $e^+ e^-$ colliders for the center of mass energies $\sqrt{s} =
1$~and~2~TeV. In both cases we find that these contributions are considerably
larger than the standard contributions considered in the literature.
| [
{
"created": "Fri, 12 Nov 1993 20:23:58 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Doncheski",
"Michael A.",
""
],
[
"Godfrey",
"Stephen",
""
]
] | We calculate the resolved photon contribution to leptoquark production at $e\gamma$ colliders for the center of mass energies $\sqrt s=500$~GeV and 1~TeV. We also calculate the resolved photon contribution to leptoquark production at $e^+ e^-$ colliders for the center of mass energies $\sqrt{s} = 1$~and~2~TeV. In both cases we find that these contributions are considerably larger than the standard contributions considered in the literature. |
1605.02368 | Yoshitaro Takaesu | Kaoru Hagiwara, Pyungwon Ko, Naotoshi Okamura and Yoshitaro Takaesu | Revisiting T2KK and T2KO physics potential and $\nu_\mu$ -
$\bar{\nu}_\mu$ beam ratio | 33 pages, 16 figures, 5 tables | Eur. Phys. J. C (2017) 77: 138 | 10.1140/epjc/s10052-017-4684-1 | KEK-TH-1868, UT-16-21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We revisit the sensitivity study of the Tokai-to-Kamioka-and-Korea (T2KK) and
Tokai-to-Kamioka-and-Oki (T2KO) proposals where a water Cerenkov detector with
the 100 kton fiducial volume is placed in Korea ($L = 1000$ km) and Oki island
($L = 653$ km) in Japan, respectively, in addition to the Super-Kamiokande for
determination of the neutrino mass hierarchy and leptonic CP phase
($\delta_{CP}$). We systematically study the running ratio of the $\nu_\mu$ and
$\bar{\nu}_\mu$ focusing beams with dedicated background estimation for the
$\nu_e$ appearance and $\nu_\mu$ disappearance signals, especially improving
treatment of the neutral current $\pi^0$ backgrounds. Using a $\nu_\mu$ -
$\bar{\nu}_\mu$ beam ratio between 3 : 2 and 2.5 : 2.5 (in unit of $10^{21}$POT
with the proton energy of 40 GeV), the mass hierarchy determination with the
median sensitivity of 3 - 5 $\sigma$ by the T2KK and 1 - 4 $\sigma$ by the T2KO
experiment are expected when $\sin^2\theta_{23} = 0.5$, depending on the mass
hierarchy pattern and CP phase. These sensitivities are enhanced (reduced) by
$30\%$ - $40\%$ in $\Delta \chi^2$ when $\sin^2\theta_{23} = 0.6\, (0.4)$. The
CP phase is measured with the uncertainty of $20^\circ$ - $50^\circ$ by the
T2KK and T2KO using the $\nu_\mu$ - $\bar{\nu}_\mu$ focusing beam ratio between
3.5 : 1.5 and 1.5 : 3.5. These findings indicate that inclusion of the
$\bar{\nu}_\mu$ focusing beam improves the sensitivities of the T2KK and T2KO
experiments to both the mass hierarchy determination and leptonic CP phase
measurement simultaneously with the preferred beam ratio being between 3 : 2 -
2.5 : 2.5 ($\times 10^{21}$POT).
| [
{
"created": "Sun, 8 May 2016 21:06:25 GMT",
"version": "v1"
},
{
"created": "Sun, 15 May 2016 00:48:54 GMT",
"version": "v2"
},
{
"created": "Wed, 1 Jun 2016 00:49:18 GMT",
"version": "v3"
},
{
"created": "Wed, 28 Sep 2016 04:33:55 GMT",
"version": "v4"
},
{
"created": "Wed, 8 Mar 2017 04:32:23 GMT",
"version": "v5"
}
] | 2017-03-09 | [
[
"Hagiwara",
"Kaoru",
""
],
[
"Ko",
"Pyungwon",
""
],
[
"Okamura",
"Naotoshi",
""
],
[
"Takaesu",
"Yoshitaro",
""
]
] | We revisit the sensitivity study of the Tokai-to-Kamioka-and-Korea (T2KK) and Tokai-to-Kamioka-and-Oki (T2KO) proposals where a water Cerenkov detector with the 100 kton fiducial volume is placed in Korea ($L = 1000$ km) and Oki island ($L = 653$ km) in Japan, respectively, in addition to the Super-Kamiokande for determination of the neutrino mass hierarchy and leptonic CP phase ($\delta_{CP}$). We systematically study the running ratio of the $\nu_\mu$ and $\bar{\nu}_\mu$ focusing beams with dedicated background estimation for the $\nu_e$ appearance and $\nu_\mu$ disappearance signals, especially improving treatment of the neutral current $\pi^0$ backgrounds. Using a $\nu_\mu$ - $\bar{\nu}_\mu$ beam ratio between 3 : 2 and 2.5 : 2.5 (in unit of $10^{21}$POT with the proton energy of 40 GeV), the mass hierarchy determination with the median sensitivity of 3 - 5 $\sigma$ by the T2KK and 1 - 4 $\sigma$ by the T2KO experiment are expected when $\sin^2\theta_{23} = 0.5$, depending on the mass hierarchy pattern and CP phase. These sensitivities are enhanced (reduced) by $30\%$ - $40\%$ in $\Delta \chi^2$ when $\sin^2\theta_{23} = 0.6\, (0.4)$. The CP phase is measured with the uncertainty of $20^\circ$ - $50^\circ$ by the T2KK and T2KO using the $\nu_\mu$ - $\bar{\nu}_\mu$ focusing beam ratio between 3.5 : 1.5 and 1.5 : 3.5. These findings indicate that inclusion of the $\bar{\nu}_\mu$ focusing beam improves the sensitivities of the T2KK and T2KO experiments to both the mass hierarchy determination and leptonic CP phase measurement simultaneously with the preferred beam ratio being between 3 : 2 - 2.5 : 2.5 ($\times 10^{21}$POT). |
hep-ph/0506178 | Werner Sauter | V. P. Goncalves, W. K. Sauter | Double vector meson production from the BFKL equation | 13 pages, 3 tables, 7 figures. Minor changes. Accepted for
publication in Eur. Phys. J. C | Eur.Phys.J.C44:515-522,2005 | 10.1140/epjc/s2005-02392-8 | null | hep-ph | null | The double vector meson production in two photon collisions is addressed
assuming that the color singlet $t$-channel exchange carries large momentum
transfer. We consider the non-forward solution of the BFKL equation at high
energy and large momentum transfer and estimate the total and differential
cross section for the process $\gamma \gamma \to V_1 V_2$, where $V_1$ and
$V_2$ can be any two vector mesons ($V_i = \rho, \omega, \phi, J/\Psi,
\Upsilon$). A comparison between our predictions and previous theoretical
results obtained at Born level or assuming the Pomeron-exchange factorization
relations is presented. Our results demonstrate that the BFKL dynamics implies
an enhancement of the cross sections. Predictions for the future linear
colliders (TESLA, CLIC and ILC) are given.
| [
{
"created": "Fri, 17 Jun 2005 18:09:35 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Sep 2005 15:33:07 GMT",
"version": "v2"
}
] | 2009-01-07 | [
[
"Goncalves",
"V. P.",
""
],
[
"Sauter",
"W. K.",
""
]
] | The double vector meson production in two photon collisions is addressed assuming that the color singlet $t$-channel exchange carries large momentum transfer. We consider the non-forward solution of the BFKL equation at high energy and large momentum transfer and estimate the total and differential cross section for the process $\gamma \gamma \to V_1 V_2$, where $V_1$ and $V_2$ can be any two vector mesons ($V_i = \rho, \omega, \phi, J/\Psi, \Upsilon$). A comparison between our predictions and previous theoretical results obtained at Born level or assuming the Pomeron-exchange factorization relations is presented. Our results demonstrate that the BFKL dynamics implies an enhancement of the cross sections. Predictions for the future linear colliders (TESLA, CLIC and ILC) are given. |
hep-ph/0201190 | Richard Woloshyn | R. Lewis, W. Wilcox, R.M. Woloshyn | Strange-quark Current in the Nucleon from Lattice QCD | 12 pages, 9 figures, Presented at EMI 2001 | null | 10.1142/9789812777218_0055 | BU-HEPP-06-01, TRI-PP-02-01 | hep-ph | null | The contribution of the strange-quark current to the electromagnetic form
factors of the nucleon is studied using lattice QCD. The strange current matrix
elements from our lattice calculation are analyzed in two different ways, the
differential method used in an earlier work by Wilcox and a cumulative method
which sums over all current insertion times. The preliminary results of our
simulation indicate the importance of high statistics, and that consistent
results between the varying analysis methods can be achieved. Although this
simulation does not yet yield a number that can be compared to experiment,
several criteria useful in assessing the robustness of a signal extracted from
a noisy background are presented.
| [
{
"created": "Mon, 21 Jan 2002 19:13:00 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Lewis",
"R.",
""
],
[
"Wilcox",
"W.",
""
],
[
"Woloshyn",
"R. M.",
""
]
] | The contribution of the strange-quark current to the electromagnetic form factors of the nucleon is studied using lattice QCD. The strange current matrix elements from our lattice calculation are analyzed in two different ways, the differential method used in an earlier work by Wilcox and a cumulative method which sums over all current insertion times. The preliminary results of our simulation indicate the importance of high statistics, and that consistent results between the varying analysis methods can be achieved. Although this simulation does not yet yield a number that can be compared to experiment, several criteria useful in assessing the robustness of a signal extracted from a noisy background are presented. |
0906.0890 | Kimmo Tuominen | T. Kahara, K. Tuominen | Effective models of two-flavor QCD: from small towards large $m_q$ | null | Phys.Rev.D80:114022,2009 | 10.1103/PhysRevD.80.114022 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study effective models of chiral fields and Polyakov loop expected to
describe the dynamics responsible for the phase structure of two-flavor QCD. We
consider chiral sector described either using linear sigma model or
Nambu-Jona-Lasinio model and study how these models, on the mean-field level
when coupled with the Polyakov loop, behave as a function of increasing bare
quark (or pion) mass. We find qualitatively similar behaviors for the cases of
linear sigma model and Nambu-Jona-Lasinio model and, relating to existing
lattice data, show that one cannot conclusively decide which or the two
approximate symmetries drives the phase transitions near the physical point.
| [
{
"created": "Thu, 4 Jun 2009 12:02:35 GMT",
"version": "v1"
}
] | 2014-11-20 | [
[
"Kahara",
"T.",
""
],
[
"Tuominen",
"K.",
""
]
] | We study effective models of chiral fields and Polyakov loop expected to describe the dynamics responsible for the phase structure of two-flavor QCD. We consider chiral sector described either using linear sigma model or Nambu-Jona-Lasinio model and study how these models, on the mean-field level when coupled with the Polyakov loop, behave as a function of increasing bare quark (or pion) mass. We find qualitatively similar behaviors for the cases of linear sigma model and Nambu-Jona-Lasinio model and, relating to existing lattice data, show that one cannot conclusively decide which or the two approximate symmetries drives the phase transitions near the physical point. |
2202.13567 | Ijaz Ahmed | Ijaz Ahmed, Mashal Shakar, M. U. Ashraf, Jamil Muhammad, Taimoor
Khurshid | Effect of Polarized Colliding Beam on Higgs Boson production at the
Lepton Collider | 19 pages,14 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Different production processes involving the Higgs boson, such as
annihilation and W/Z boson fusion, will be observed in the International Linear
Collider (ILC). The ILC operates at a center-of-mass (CM) energy of $\sqrt{s}$
= 200-1000 GeV. The study reveals that the production cross-section can either
be enhanced or reduced depending on the CM energy and the specific combination
used, which has implications for selecting appropriate production processes.
Additionally, this investigation highlights that by polarizing beams, the
number of measurable observables increases. These observables, such as
left$~$right asymmetry, detailed effective polarization, and adequate effective
luminosity, are crucial to ascertain contemporary physical parameters in
physics models absurdly the Standard Model (SM).
| [
{
"created": "Mon, 28 Feb 2022 06:38:36 GMT",
"version": "v1"
},
{
"created": "Wed, 26 Jul 2023 09:53:13 GMT",
"version": "v2"
},
{
"created": "Wed, 30 Aug 2023 09:03:07 GMT",
"version": "v3"
},
{
"created": "Fri, 1 Sep 2023 07:10:20 GMT",
"version": "v4"
}
] | 2023-09-04 | [
[
"Ahmed",
"Ijaz",
""
],
[
"Shakar",
"Mashal",
""
],
[
"Ashraf",
"M. U.",
""
],
[
"Muhammad",
"Jamil",
""
],
[
"Khurshid",
"Taimoor",
""
]
] | Different production processes involving the Higgs boson, such as annihilation and W/Z boson fusion, will be observed in the International Linear Collider (ILC). The ILC operates at a center-of-mass (CM) energy of $\sqrt{s}$ = 200-1000 GeV. The study reveals that the production cross-section can either be enhanced or reduced depending on the CM energy and the specific combination used, which has implications for selecting appropriate production processes. Additionally, this investigation highlights that by polarizing beams, the number of measurable observables increases. These observables, such as left$~$right asymmetry, detailed effective polarization, and adequate effective luminosity, are crucial to ascertain contemporary physical parameters in physics models absurdly the Standard Model (SM). |
1506.04058 | Eligio Lisi | E. Lisi (INFN, Bari), A. Rotunno (U. of Bari), F. Simkovic (Comenius
U. & JINR & CTU Prague) | Degeneracies of particle and nuclear physics uncertainties in
neutrinoless double beta decay | 11 pages, including 5 figures (one new). Clarifications added in the
text. To appear in Phys. Rev. D | Phys. Rev. D 92, 093004 (2015) | 10.1103/PhysRevD.92.093004 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Theoretical estimates for the half life of neutrinoless double beta decay in
candidate nuclei are affected by both particle and nuclear physics
uncertainties, which may complicate the interpretation of decay signals or
limits. We study such uncertainties and their degeneracies in the following
context: three nuclei of great interest for large-scale experiments (76-Ge,
130-Te, 136-Xe), two representative particle physics mechanisms (light and
heavy Majorana neutrino exchange), and a large set of nuclear matrix elements
(NME), computed within the quasiparticle random phase approximation (QRPA). It
turns out that the main theoretical uncertainties, associated with the
effective axial coupling g_A and with the nucleon-nucleon potential, can be
parametrized in terms of NME rescaling factors, up to small residuals. From
this parametrization, the following QRPA features emerge: (1) the NME
dependence on g_A is milder than quadratic; (2) in each of the two mechanisms,
the relevant lepton number violating parameter is largely degenerate with the
NME rescaling factors; and (3) the light and heavy neutrino exchange mechanisms
are basically degenerate in the above three nuclei. We comment on the
challenging theoretical and experimental improvements required to reduce such
particle and nuclear physics uncertainties and their degeneracies.
| [
{
"created": "Fri, 12 Jun 2015 16:15:34 GMT",
"version": "v1"
},
{
"created": "Mon, 26 Oct 2015 18:44:53 GMT",
"version": "v2"
}
] | 2015-11-11 | [
[
"Lisi",
"E.",
"",
"INFN, Bari"
],
[
"Rotunno",
"A.",
"",
"U. of Bari"
],
[
"Simkovic",
"F.",
"",
"Comenius\n U. & JINR & CTU Prague"
]
] | Theoretical estimates for the half life of neutrinoless double beta decay in candidate nuclei are affected by both particle and nuclear physics uncertainties, which may complicate the interpretation of decay signals or limits. We study such uncertainties and their degeneracies in the following context: three nuclei of great interest for large-scale experiments (76-Ge, 130-Te, 136-Xe), two representative particle physics mechanisms (light and heavy Majorana neutrino exchange), and a large set of nuclear matrix elements (NME), computed within the quasiparticle random phase approximation (QRPA). It turns out that the main theoretical uncertainties, associated with the effective axial coupling g_A and with the nucleon-nucleon potential, can be parametrized in terms of NME rescaling factors, up to small residuals. From this parametrization, the following QRPA features emerge: (1) the NME dependence on g_A is milder than quadratic; (2) in each of the two mechanisms, the relevant lepton number violating parameter is largely degenerate with the NME rescaling factors; and (3) the light and heavy neutrino exchange mechanisms are basically degenerate in the above three nuclei. We comment on the challenging theoretical and experimental improvements required to reduce such particle and nuclear physics uncertainties and their degeneracies. |
1604.02263 | Koji Ishiwata | Shin'ichiro Ando, Koji Ishiwata | Constraining particle dark matter using local galaxy distribution | 23 pages, 11 figures, published version | JCAP06(2016)045 | 10.1088/1475-7516/2016/06/045 | KANAZAWA-16-03 | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has been long discussed that cosmic rays may contain signals of dark
matter. In the last couple of years an anomaly of cosmic-ray positrons has
drawn a lot of attentions, and recently an excess in cosmic-ray anti-proton has
been reported by AMS-02 collaboration. Both excesses may indicate towards
decaying or annihilating dark matter with a mass of around 1-10 TeV. In this
article we study the gamma rays from dark matter and constraints from cross
correlations with distribution of galaxies, particularly in a local volume. We
find that gamma rays due to inverse-Compton process have large intensity, and
hence they give stringent constraints on dark matter scenarios in the TeV scale
mass regime. Taking the recent developments in modeling astrophysical gamma-ray
sources as well as comprehensive possibilities of the final state products of
dark matter decay or annihilation into account, we show that the parameter
regions of decaying dark matter that are suggested to explain the excesses are
excluded. We also discuss the constrains on annihilating scenarios.
| [
{
"created": "Fri, 8 Apr 2016 07:58:20 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Jun 2016 07:20:22 GMT",
"version": "v2"
}
] | 2016-06-29 | [
[
"Ando",
"Shin'ichiro",
""
],
[
"Ishiwata",
"Koji",
""
]
] | It has been long discussed that cosmic rays may contain signals of dark matter. In the last couple of years an anomaly of cosmic-ray positrons has drawn a lot of attentions, and recently an excess in cosmic-ray anti-proton has been reported by AMS-02 collaboration. Both excesses may indicate towards decaying or annihilating dark matter with a mass of around 1-10 TeV. In this article we study the gamma rays from dark matter and constraints from cross correlations with distribution of galaxies, particularly in a local volume. We find that gamma rays due to inverse-Compton process have large intensity, and hence they give stringent constraints on dark matter scenarios in the TeV scale mass regime. Taking the recent developments in modeling astrophysical gamma-ray sources as well as comprehensive possibilities of the final state products of dark matter decay or annihilation into account, we show that the parameter regions of decaying dark matter that are suggested to explain the excesses are excluded. We also discuss the constrains on annihilating scenarios. |
2102.13112 | Matthias Neubert | Martin Bauer (U. Durham), Matthias Neubert (U. Mainz), Sophie Renner
(SISSA), Marvin Schnubel (U. Mainz), Andrea Thamm (U. Melbourne) | Consistent treatment of axions in the weak chiral Lagrangian | 5 pages, 1 figure | Phys. Rev. Lett. 127, 081803 (2021) | 10.1103/PhysRevLett.127.081803 | IPPP/20-82, MITP/21-007, ZU-TH-01/21 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a consistent implementation of weak decays involving an axion or
axion-like particle in the context of an effective chiral Lagrangian. We argue
that previous treatments of such processes have used an incorrect
representation of the flavor-changing quark currents in the chiral theory. As
an application, we derive model-independent results for the decays $K^-\to\pi^-
a$ and $\pi^-\to e^-\bar\nu_e a$ at leading order in the chiral expansion and
for arbitrary axion couplings and mass. In particular, we find that the
$K^-\to\pi^- a$ branching ratio is almost 40 times larger than previously
estimated.
| [
{
"created": "Thu, 25 Feb 2021 19:00:00 GMT",
"version": "v1"
}
] | 2021-08-25 | [
[
"Bauer",
"Martin",
"",
"U. Durham"
],
[
"Neubert",
"Matthias",
"",
"U. Mainz"
],
[
"Renner",
"Sophie",
"",
"SISSA"
],
[
"Schnubel",
"Marvin",
"",
"U. Mainz"
],
[
"Thamm",
"Andrea",
"",
"U. Melbourne"
]
] | We present a consistent implementation of weak decays involving an axion or axion-like particle in the context of an effective chiral Lagrangian. We argue that previous treatments of such processes have used an incorrect representation of the flavor-changing quark currents in the chiral theory. As an application, we derive model-independent results for the decays $K^-\to\pi^- a$ and $\pi^-\to e^-\bar\nu_e a$ at leading order in the chiral expansion and for arbitrary axion couplings and mass. In particular, we find that the $K^-\to\pi^- a$ branching ratio is almost 40 times larger than previously estimated. |
hep-ph/9703383 | Johan Linde | Johan Linde and Hakan Snellman | Charmonium in the instantaneous approximation | 36 pages incuding 4 figures, REVTeX, accepted for publication in
Nucl. Phys. A | Nucl.Phys. A619 (1997) 346-378 | 10.1016/S0375-9474(97)00144-9 | null | hep-ph | null | The charmonium system is studied in a Salpeter model with a vector plus
scalar potential. We use a kinematical formalism based on the one developed by
Suttorp, and present general eigenvalue equations and expressions for decay
observables in an onium system for such a potential both in the Feynman and
Coulomb gauges. Special attention is paid to the problem with renormalization
of the lepton pair decays, and we argue that they must be defined relative to
one of the experimental decay widths because renormalization of the vertex
function is not possible. The parameters of the model are determined by a fit
to the mass spectrum and the lepton pair decay rates. Two gamma decays and E1
and M1 transitions are then calculated and found to be well accounted for. No
significant differences in the results in Feynman or Coulomb gauge are found. A
comparison is made, regarding the electromagnetic transitions, between the full
and reduced Salpeter equation. A large difference is found showing the
importance of using the full Salpeter equation.
| [
{
"created": "Fri, 21 Mar 1997 09:57:11 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Linde",
"Johan",
""
],
[
"Snellman",
"Hakan",
""
]
] | The charmonium system is studied in a Salpeter model with a vector plus scalar potential. We use a kinematical formalism based on the one developed by Suttorp, and present general eigenvalue equations and expressions for decay observables in an onium system for such a potential both in the Feynman and Coulomb gauges. Special attention is paid to the problem with renormalization of the lepton pair decays, and we argue that they must be defined relative to one of the experimental decay widths because renormalization of the vertex function is not possible. The parameters of the model are determined by a fit to the mass spectrum and the lepton pair decay rates. Two gamma decays and E1 and M1 transitions are then calculated and found to be well accounted for. No significant differences in the results in Feynman or Coulomb gauge are found. A comparison is made, regarding the electromagnetic transitions, between the full and reduced Salpeter equation. A large difference is found showing the importance of using the full Salpeter equation. |
hep-ph/9301226 | David Bowser-Chao | A. Abbasabadi, David Bowser-Chao, Duane A. Dicus, and Wayne W. Repko | The effects of a strongly interacting Higgs sector on
$\gamma\,\gamma\rightarrow W_L^+\,W_L^-, Z_L^{\,0}\,Z_L^{\,0}$ scattering | 7 pp.,(figures and manuscript available by anonymous ftp from
utaphy.ph.utexas.edu in directory cpp-preprints as ggtoww.tex and ggtoww.uu),
MSUTH 92/03; [revisions: added reference to work of M. Herrero and E.
Ruiz--Morales] | Phys.Rev. D49 (1994) 547-550 | 10.1103/PhysRevD.49.547 | null | hep-ph | null | We study the effects of a strongly interacting Higgs sector on the amplitudes
for $\gamma\,\gamma\rightarrow W_L^+\,W_L^-, Z_L^{\,0}\,Z_L^{\,0}$ by
unitarizing the $W_L^+\,W_L^-, Z_L^{\,0}\,Z_L^{\,0}, \gamma\,\gamma$ system
using the $K$--matrix technique. Unitarization produces substantial corrections
to the cross sections for gauge boson pair production by photon fusion when
$m_H \agt 5-10\;$TeV.
| [
{
"created": "Sun, 10 Jan 1993 11:55:33 GMT",
"version": "v1"
},
{
"created": "Tue, 16 Feb 1993 15:57:45 GMT",
"version": "v2"
}
] | 2009-10-22 | [
[
"Abbasabadi",
"A.",
""
],
[
"Bowser-Chao",
"David",
""
],
[
"Dicus",
"Duane A.",
""
],
[
"Repko",
"Wayne W.",
""
]
] | We study the effects of a strongly interacting Higgs sector on the amplitudes for $\gamma\,\gamma\rightarrow W_L^+\,W_L^-, Z_L^{\,0}\,Z_L^{\,0}$ by unitarizing the $W_L^+\,W_L^-, Z_L^{\,0}\,Z_L^{\,0}, \gamma\,\gamma$ system using the $K$--matrix technique. Unitarization produces substantial corrections to the cross sections for gauge boson pair production by photon fusion when $m_H \agt 5-10\;$TeV. |
hep-ph/9708488 | Csaba Boros | Liang Zuo-tang (U.Shandong) and C. Boros (U.Adelaide, FU Berlin) | Hyperon polarization and single spin left-right asymmetry in inclusive
production processes at high energies | REVTeX, 12 pages, 2 figures embedded | Phys.Rev.Lett.79:3608-3611,1997 | 10.1103/PhysRevLett.79.3608 | ADP-97-41/T269 | hep-ph | null | It is shown that the polarization of hyperons observed in high energy
collisions using unpolarized hadron beams and unpolarized nucleon or nuclear
targets is closely related to the left-right asymmetries observed in single
spin inclusive hadron production processes. The relationship is most obvious
for the production of the hyperons which have only one common valence quark
with the projectile. Examples of this kind are given. Further implications of
the existence of large polarization for hyperon which has two valence quarks in
common with the projectile and their consequences are discussed. A comparison
with the available data is made. Further tests are suggested.
| [
{
"created": "Fri, 29 Aug 1997 10:22:29 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Nov 1997 06:19:35 GMT",
"version": "v2"
},
{
"created": "Tue, 25 Nov 1997 01:13:56 GMT",
"version": "v3"
}
] | 2008-11-26 | [
[
"Zuo-tang",
"Liang",
"",
"U.Shandong"
],
[
"Boros",
"C.",
"",
"U.Adelaide, FU Berlin"
]
] | It is shown that the polarization of hyperons observed in high energy collisions using unpolarized hadron beams and unpolarized nucleon or nuclear targets is closely related to the left-right asymmetries observed in single spin inclusive hadron production processes. The relationship is most obvious for the production of the hyperons which have only one common valence quark with the projectile. Examples of this kind are given. Further implications of the existence of large polarization for hyperon which has two valence quarks in common with the projectile and their consequences are discussed. A comparison with the available data is made. Further tests are suggested. |
1011.5612 | A. Tawfik | A. Tawfik (Egyptian Ctr. Theor. Phys., Cairo) | Antiproton-to-Proton Ratios for ALICE Heavy-Ion Collisions | 5 pages, 1 eps figure, revtex4-style | Nucl.Phys.A859:63-72,2011 | 10.1016/j.nuclphysa.2011.04.014 | ECTP-2010-11 | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Assuming that the final state of hadronization takes place along the
freezeout line, which is defined by a constant entropy density, the
antiproton-to-proton ratios produced in heavy-ion collisions are studied in
framework of the hadron resonance gas (HRG) model. A phase transition from
quark--gluon plasma to hadrons, a hadronization, has been conjectured in order
to allow modifications in the phase space volume and thus in single--particle
distribution function. Implementing both modifications in the grand--canonical
partition function and taking into account the experimental acceptance in
heavy-ion collisions, the antiproton-to-proton ratios over center-of-mass
energies $\sqrt{s}$ ranging from AGS to RHIC are very well reproduced by the
HRG model. Comparing with the same particle ratios in $pp$ collisions results
in a gradually narrowing discrepancy with increasing $\sqrt{s}$. At LHC energy,
the ALICE antiproton-to-proton ratios in $pp$ collisions turn to be very well
described by HRG model as well. It is likely that the ALICE heavy-ion program
will produce the same antiproton-to-proton ratios as the $pp$ program.
Furthermore, the ratio gets very close to unity indicating that the
matter-antimatter asymmetry nearly vanishes. The chemical potential calculated
at this energy strengthens the assumption of almost fully matter-antimatter
symmetry at LHC energy.
| [
{
"created": "Thu, 25 Nov 2010 12:34:00 GMT",
"version": "v1"
}
] | 2011-07-28 | [
[
"Tawfik",
"A.",
"",
"Egyptian Ctr. Theor. Phys., Cairo"
]
] | Assuming that the final state of hadronization takes place along the freezeout line, which is defined by a constant entropy density, the antiproton-to-proton ratios produced in heavy-ion collisions are studied in framework of the hadron resonance gas (HRG) model. A phase transition from quark--gluon plasma to hadrons, a hadronization, has been conjectured in order to allow modifications in the phase space volume and thus in single--particle distribution function. Implementing both modifications in the grand--canonical partition function and taking into account the experimental acceptance in heavy-ion collisions, the antiproton-to-proton ratios over center-of-mass energies $\sqrt{s}$ ranging from AGS to RHIC are very well reproduced by the HRG model. Comparing with the same particle ratios in $pp$ collisions results in a gradually narrowing discrepancy with increasing $\sqrt{s}$. At LHC energy, the ALICE antiproton-to-proton ratios in $pp$ collisions turn to be very well described by HRG model as well. It is likely that the ALICE heavy-ion program will produce the same antiproton-to-proton ratios as the $pp$ program. Furthermore, the ratio gets very close to unity indicating that the matter-antimatter asymmetry nearly vanishes. The chemical potential calculated at this energy strengthens the assumption of almost fully matter-antimatter symmetry at LHC energy. |
1208.6082 | Lars Bergstrom | Lars Bergstr\"om | The 130 GeV Fingerprint of Right-Handed Neutrino Dark Matter | 7 pages, 3 figures | Phys.Rev. D86 (2012) 103514 | 10.1103/PhysRevD.86.103514 | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Recently, an interesting indication for a dark matter signal in the form of a
narrow line, or maybe two lines and/or an internal bremsstrahlung feature, has
been found in data from the Fermi-LAT satellite detector. As recent analyses
have also shown that there is little sign of extra contributions to continuum
photons, it is natural to investigate leptophilic interacting massive particle
(LIMP) models. We show that a model of radiatively generated neutrino masses
may have the properties needed to explain the Fermi-LAT structure around 130
GeV. This model was proposed some 10 years ago, and predicted a clearly
observable $\gamma$-ray signal in the Fermi-LAT (then GLAST) detector. Here, we
update and improve that analysis, and show as an example that a right-handed
neutrino of mass 135 GeV should give rise to three conspicuous effects: a broad
internal bremsstrahlung bump with maximum around 120 GeV, a 2$\gamma$ line
around 135 GeV, and a $Z\gamma$ line at 119.6 GeV (neglected in the previous
work). These features together give a good fit to the 130 GeV structure, given
the present energy resolution of the Fermi-LAT data. An attractive feature of
the model is that the particle physics properties are essentially fixed, when
relic density and mass of the right-handed neutrino dark matter particle have
been set. Puzzling features of the data at present are a slight displacement of
the signal from the galactic center, and a needed boost factor of order 5-15.
This presents a challenge for numerical simulations including both baryons and
dark matter on scales of 100 pc, and perhaps a need to go beyond the simplest
halo models. With upcoming data, the double-peak structure with the two lines
and the internal bremsstrahlung feature should be seen, if this model is
correct. With the satellite GAMMA-400, a striking fingerprint of this dark
matter candidate should then appear.
| [
{
"created": "Thu, 30 Aug 2012 05:21:54 GMT",
"version": "v1"
},
{
"created": "Mon, 3 Sep 2012 13:20:55 GMT",
"version": "v2"
}
] | 2013-04-24 | [
[
"Bergström",
"Lars",
""
]
] | Recently, an interesting indication for a dark matter signal in the form of a narrow line, or maybe two lines and/or an internal bremsstrahlung feature, has been found in data from the Fermi-LAT satellite detector. As recent analyses have also shown that there is little sign of extra contributions to continuum photons, it is natural to investigate leptophilic interacting massive particle (LIMP) models. We show that a model of radiatively generated neutrino masses may have the properties needed to explain the Fermi-LAT structure around 130 GeV. This model was proposed some 10 years ago, and predicted a clearly observable $\gamma$-ray signal in the Fermi-LAT (then GLAST) detector. Here, we update and improve that analysis, and show as an example that a right-handed neutrino of mass 135 GeV should give rise to three conspicuous effects: a broad internal bremsstrahlung bump with maximum around 120 GeV, a 2$\gamma$ line around 135 GeV, and a $Z\gamma$ line at 119.6 GeV (neglected in the previous work). These features together give a good fit to the 130 GeV structure, given the present energy resolution of the Fermi-LAT data. An attractive feature of the model is that the particle physics properties are essentially fixed, when relic density and mass of the right-handed neutrino dark matter particle have been set. Puzzling features of the data at present are a slight displacement of the signal from the galactic center, and a needed boost factor of order 5-15. This presents a challenge for numerical simulations including both baryons and dark matter on scales of 100 pc, and perhaps a need to go beyond the simplest halo models. With upcoming data, the double-peak structure with the two lines and the internal bremsstrahlung feature should be seen, if this model is correct. With the satellite GAMMA-400, a striking fingerprint of this dark matter candidate should then appear. |
1402.3186 | Nadine Fischer | Nadine Fischer, Stefan Gieseke, Simon Pl\"atzer, Peter Skands | Revisiting Radiation Patterns in $e^+e^-$ Collisions | 27 pages, 10 figures | null | 10.1140/epjc/s10052-014-2831-5 | CERN-PH-TH/2014-018, DESY-14-014, KA-TP-05-2014, MCNET-14-04 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We propose four simple event-shape variables for semi-inclusive $e^+e^- \to
4$-jet events. The observables and cuts are designed to be especially sensitive
to subleading aspects of the event structure, and allow to test the reliability
of phenomenological QCD models in greater detail. Three of them, $\theta_{14}$,
$\theta^*$, and $C_2^{(1/5)}$, focus on soft emissions off three-jet topologies
with a small opening angle, for which coherence effects beyond the leading QCD
dipole pattern are expected to be enhanced. A complementary variable,
$M_L^2/M_H^2$, measures the ratio of the hemisphere masses in 4-jet events with
a compressed scale hierarchy (Durham $y_{23}\sim y_{34}$), for which subleading
$1\to 3$ splitting effects are expected to be enhanced. We consider several
different parton-shower models, spanning both conventional and dipole/antenna
ones, all tuned to the same $e^+e^-$ reference data, and show that a
measurement of the proposed observables would allow for additional significant
discriminating power between the models.
| [
{
"created": "Thu, 13 Feb 2014 15:46:06 GMT",
"version": "v1"
}
] | 2015-06-18 | [
[
"Fischer",
"Nadine",
""
],
[
"Gieseke",
"Stefan",
""
],
[
"Plätzer",
"Simon",
""
],
[
"Skands",
"Peter",
""
]
] | We propose four simple event-shape variables for semi-inclusive $e^+e^- \to 4$-jet events. The observables and cuts are designed to be especially sensitive to subleading aspects of the event structure, and allow to test the reliability of phenomenological QCD models in greater detail. Three of them, $\theta_{14}$, $\theta^*$, and $C_2^{(1/5)}$, focus on soft emissions off three-jet topologies with a small opening angle, for which coherence effects beyond the leading QCD dipole pattern are expected to be enhanced. A complementary variable, $M_L^2/M_H^2$, measures the ratio of the hemisphere masses in 4-jet events with a compressed scale hierarchy (Durham $y_{23}\sim y_{34}$), for which subleading $1\to 3$ splitting effects are expected to be enhanced. We consider several different parton-shower models, spanning both conventional and dipole/antenna ones, all tuned to the same $e^+e^-$ reference data, and show that a measurement of the proposed observables would allow for additional significant discriminating power between the models. |
hep-ph/9305287 | Geert Jan van Oldenborgh | Frank Cuypers, Geert Jan van Oldenborgh and Reinhold R\"uckl | Supersymmetric Signals in $e^-e^-$ Collisions | 18 pages including 8 figures, included as uufiled .ps files. LaTeX
with axodraw.sty for Feynman graphs, epsf.sty for figures; the texfile and
complete PSfile are available via ftp from pss058.psi.ch. CERN-TH.6807/93,
MPI-Ph/93-28, PSI-93-11 | Nucl.Phys. B409 (1993) 128-143 | 10.1016/0550-3213(93)90449-Y | null | hep-ph | null | We consider the production and decay of selectrons and charginos in $e^-e^-$
collisions. The advantage over usual $e^+e^-$ collisions is the very low level
of standard model backgrounds which should make the discovery of selectrons or
charginos relatively straightforward. The use of polarized beams provides an
additional powerful tool to determine the supersymmetry parameters.
| [
{
"created": "Wed, 19 May 1993 16:16:52 GMT",
"version": "v1"
}
] | 2009-10-22 | [
[
"Cuypers",
"Frank",
""
],
[
"van Oldenborgh",
"Geert Jan",
""
],
[
"Rückl",
"Reinhold",
""
]
] | We consider the production and decay of selectrons and charginos in $e^-e^-$ collisions. The advantage over usual $e^+e^-$ collisions is the very low level of standard model backgrounds which should make the discovery of selectrons or charginos relatively straightforward. The use of polarized beams provides an additional powerful tool to determine the supersymmetry parameters. |
hep-ph/0010265 | Johan Bijnens | Johan Bijnens (Lund) | Weak Interactions of Light Flavours | Lectures given at the Advanced School on QCD at Benasque, Spain, 3-6
July 2000. 27 pages | null | null | LU TP 00-44 | hep-ph | null | An overview is given of weak interaction physics of the light flavours. It
starts with the definition of the CKM matrix and the measurement of its
components in the light-flavour sector via semi-leptonic decays. The main part
of the lectures is devoted to non-leptonic decays with a main emphasis on
analytical calculations of $K\to\pi\pi$ and $K^0\leftrightarrow \kob$ mixing.
It finishes with an overview of Chiral Perturbation Theory in $K\to3\pi$ and of
rare Kaon decays.
| [
{
"created": "Mon, 23 Oct 2000 10:30:02 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bijnens",
"Johan",
"",
"Lund"
]
] | An overview is given of weak interaction physics of the light flavours. It starts with the definition of the CKM matrix and the measurement of its components in the light-flavour sector via semi-leptonic decays. The main part of the lectures is devoted to non-leptonic decays with a main emphasis on analytical calculations of $K\to\pi\pi$ and $K^0\leftrightarrow \kob$ mixing. It finishes with an overview of Chiral Perturbation Theory in $K\to3\pi$ and of rare Kaon decays. |
2111.03194 | Colin Weller | Colin M. Weller, Gerald A. Miller | Confinement in Two-Dimensional QCD and the Infinitely Long Pion | null | null | 10.1103/PhysRevD.105.036009 | null | hep-ph nucl-th | http://creativecommons.org/licenses/by/4.0/ | Three current models of QCD in (1+1) dimensions are examined and extended in
light-front coordinates. A pion of high momentum is found to have an infinite
extent along its direction of motion.
| [
{
"created": "Thu, 4 Nov 2021 23:15:57 GMT",
"version": "v1"
},
{
"created": "Wed, 24 Nov 2021 20:25:52 GMT",
"version": "v2"
}
] | 2022-03-02 | [
[
"Weller",
"Colin M.",
""
],
[
"Miller",
"Gerald A.",
""
]
] | Three current models of QCD in (1+1) dimensions are examined and extended in light-front coordinates. A pion of high momentum is found to have an infinite extent along its direction of motion. |
2104.03316 | Andreas Helset | Andreas Helset, Clara Murgui and Mark B. Wise | Simple models with both baryon and lepton number violation by two units | 10 pages, 1 figure | Phys. Rev. D 104, 015029 (2021) | 10.1103/PhysRevD.104.015029 | CALT-TH/2021-014 | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct simple renormalizable extensions of the standard model where the
leading baryon number violating processes have $\Delta B = \pm \Delta L = -2$.
These models contain additional scalars. The simplest models contain a color
singlet and a colored sextet. For such baryon number violation to be observed
in experiments, the scalars cannot be much heavier than a few TeV. We find that
such models are strongly constrained by LHC physics, LEP physics, and flavor
physics.
| [
{
"created": "Wed, 7 Apr 2021 18:00:00 GMT",
"version": "v1"
}
] | 2021-08-04 | [
[
"Helset",
"Andreas",
""
],
[
"Murgui",
"Clara",
""
],
[
"Wise",
"Mark B.",
""
]
] | We construct simple renormalizable extensions of the standard model where the leading baryon number violating processes have $\Delta B = \pm \Delta L = -2$. These models contain additional scalars. The simplest models contain a color singlet and a colored sextet. For such baryon number violation to be observed in experiments, the scalars cannot be much heavier than a few TeV. We find that such models are strongly constrained by LHC physics, LEP physics, and flavor physics. |
hep-ph/0103238 | shunzo Kumano | M. Hirai, S. Kumano, M. Miyama | Parametrization of nuclear parton distributions | 1+11 pages, LaTeX, amsmath.sty, wrapfig.sty, graphicx.sty, ias.cls,
ias.sty, pramana.sty, pmana10.sty, pbib.sty, times.sty, 9 eps figures.
Invited talk given at the International Symposium on Nuclear Physics, Mumbai,
India, Dec. 18-22, 2000, to be published in proceedings. Complete postscript
file is available at http://www-hs.phys.saga-u.ac.jp Email:
hirai@hsg.phys.saga-u.ac.jp, kumanos@cc.saga-u.ac.jp,
miyama@comp.metro-u.ac.jp | Pramana 57:445-458,2001 | 10.1007/s12043-001-0052-6 | SAGA-HE-171-01, TMU-NT-01-02 | hep-ph hep-ex nucl-th | null | Optimum nuclear parton distributions are obtained by analyzing available
experimental data on electron and muon deep inelastic scattering (DIS). The
distributions are given at Q^2=1 GeV^2 with a number of parameters, which are
determined by a chi^2 analysis of the data. Valence-quark distributions are
relatively well determined at medium x, but they are slightly dependent on the
assumed parametrization form particularly at small x. Although antiquark
distributions are shadowed at small x, their behavior is not obvious at medium
x from the F_2 data. The gluon distributions could not be restricted well by
the inclusive DIS data; however, the analysis tends to support the gluon
shadowing at small x. We provide analytical expressions and computer
subroutines for calculating the nuclear parton distributions, so that other
researchers could use them for applications to other high-energy nuclear
reactions.
| [
{
"created": "Thu, 22 Mar 2001 02:11:43 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Hirai",
"M.",
""
],
[
"Kumano",
"S.",
""
],
[
"Miyama",
"M.",
""
]
] | Optimum nuclear parton distributions are obtained by analyzing available experimental data on electron and muon deep inelastic scattering (DIS). The distributions are given at Q^2=1 GeV^2 with a number of parameters, which are determined by a chi^2 analysis of the data. Valence-quark distributions are relatively well determined at medium x, but they are slightly dependent on the assumed parametrization form particularly at small x. Although antiquark distributions are shadowed at small x, their behavior is not obvious at medium x from the F_2 data. The gluon distributions could not be restricted well by the inclusive DIS data; however, the analysis tends to support the gluon shadowing at small x. We provide analytical expressions and computer subroutines for calculating the nuclear parton distributions, so that other researchers could use them for applications to other high-energy nuclear reactions. |
hep-ph/0110323 | Elisabeth Kraus | Elisabeth Kraus | Calculating the anomalous supersymmetry breaking in Super-Yang-Mills
theories with local coupling | 22 pages, LaTeX, v2: references added | Phys.Rev. D65 (2002) 105003 | 10.1103/PhysRevD.65.105003 | BN-TH-01-08 | hep-ph hep-th | null | Supersymmetric Yang-Mills-theories with local gauge coupling have a new type
of anomalous breaking, which appears as a breaking of supersymmetry in the
Wess-Zumino-gauge. The anomalous breaking generates the two-loop order of the
gauge $\beta$-function in terms of the one-loop $\beta$-function and the
anomaly coefficient. We determine the anomaly coefficient in the
Wess-Zumino-gauge by solving the relevant supersymmetry identities. For this
purpose we use a background gauge and show that the anomaly coefficient is
uniquely determined by convergent one-loop integrals. When evaluating the
one-loop diagrams in the background gauge, it is seen that the anomaly
coefficient is determined by the Feynman-gauge value of the one-loop vertex
function to the topological term $G \tilde G$ at vanishing momenta.
| [
{
"created": "Thu, 25 Oct 2001 07:48:01 GMT",
"version": "v1"
},
{
"created": "Wed, 31 Oct 2001 11:54:27 GMT",
"version": "v2"
}
] | 2009-11-07 | [
[
"Kraus",
"Elisabeth",
""
]
] | Supersymmetric Yang-Mills-theories with local gauge coupling have a new type of anomalous breaking, which appears as a breaking of supersymmetry in the Wess-Zumino-gauge. The anomalous breaking generates the two-loop order of the gauge $\beta$-function in terms of the one-loop $\beta$-function and the anomaly coefficient. We determine the anomaly coefficient in the Wess-Zumino-gauge by solving the relevant supersymmetry identities. For this purpose we use a background gauge and show that the anomaly coefficient is uniquely determined by convergent one-loop integrals. When evaluating the one-loop diagrams in the background gauge, it is seen that the anomaly coefficient is determined by the Feynman-gauge value of the one-loop vertex function to the topological term $G \tilde G$ at vanishing momenta. |
hep-ph/9801306 | null | E.W. Kolb, A. Riotto and I.I. Tkachev | GUT baryogenesis after preheating: numerical study of the production and
decay of X-bosons | 13 pages, LaTeX file, 3 figures. One reference added and minor
changes | Phys.Lett. B423 (1998) 348-354 | 10.1016/S0370-2693(98)00134-8 | FERMILAB-Pub-97/433-A, CERN-TH/97-376 | hep-ph astro-ph hep-th | null | We perform a fully non-linear calculation of the production of supermassive
Grand Unified Theory (GUT) $X$ bosons during preheating, taking into account
the fact that they are unstable with a decay width $\Gamma_X$. We show that
parametric resonance does not develop if $\Gamma_X$ is larger than about
$10^{-2} m_X$. We compute the nonthermal number density of superheavy bosons
produced in the preheating phase and demonstrate that the observed baryon
asymmetry may be explained by GUT baryogenesis after preheating if $\Gamma_X$
is smaller than about $10^{-3} m_X$.
| [
{
"created": "Wed, 14 Jan 1998 17:42:08 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Jan 1998 09:15:36 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Kolb",
"E. W.",
""
],
[
"Riotto",
"A.",
""
],
[
"Tkachev",
"I. I.",
""
]
] | We perform a fully non-linear calculation of the production of supermassive Grand Unified Theory (GUT) $X$ bosons during preheating, taking into account the fact that they are unstable with a decay width $\Gamma_X$. We show that parametric resonance does not develop if $\Gamma_X$ is larger than about $10^{-2} m_X$. We compute the nonthermal number density of superheavy bosons produced in the preheating phase and demonstrate that the observed baryon asymmetry may be explained by GUT baryogenesis after preheating if $\Gamma_X$ is smaller than about $10^{-3} m_X$. |
2207.08842 | Jacopo Ghiglieri | Jacopo Ghiglieri and Eamonn Weitz | Classical vs quantum corrections to jet broadening in a weakly-coupled
Quark-Gluon Plasma | 26 pages plus appendices, 9 figures. v2: minor typographical fixes,
matches JHEP version | JHEP 11 (2022) 068 | 10.1007/JHEP11(2022)068 | null | hep-ph nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The transverse momentum broadening coefficient $\hat{q}$ receives both soft,
classical and radiative, quantum corrections. The former are responsible for a
large O(g) correction, whereas the latter enter at relative order $\alpha_s$,
but are enhanced by a double logarithm of the length of the medium over the
thermal wavelength. We analyze radiative corrections for a weakly-coupled
quark-gluon plasma. We find that a thermal population of dynamical gluons
changes the boundaries and reduces the size of the double-logarithmic phase
space. It also provides new subdominant logarithmic corrections. We also show
how the quantum, double-logarithmic and classical, soft phase spaces are
smoothly connected once the radiated gluon becomes soft enough. Finally, we
discuss a pathway to a determination of radiative corrections beyond the
harmonic-oscillator approximation.
| [
{
"created": "Mon, 18 Jul 2022 18:00:06 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Nov 2022 11:01:25 GMT",
"version": "v2"
}
] | 2022-11-16 | [
[
"Ghiglieri",
"Jacopo",
""
],
[
"Weitz",
"Eamonn",
""
]
] | The transverse momentum broadening coefficient $\hat{q}$ receives both soft, classical and radiative, quantum corrections. The former are responsible for a large O(g) correction, whereas the latter enter at relative order $\alpha_s$, but are enhanced by a double logarithm of the length of the medium over the thermal wavelength. We analyze radiative corrections for a weakly-coupled quark-gluon plasma. We find that a thermal population of dynamical gluons changes the boundaries and reduces the size of the double-logarithmic phase space. It also provides new subdominant logarithmic corrections. We also show how the quantum, double-logarithmic and classical, soft phase spaces are smoothly connected once the radiated gluon becomes soft enough. Finally, we discuss a pathway to a determination of radiative corrections beyond the harmonic-oscillator approximation. |
1509.03494 | Jarah Evslin | Emilio Ciuffoli, Jarah Evslin and Fengyi Zhao | Neutrino Physics with Accelerator Driven Subcritical Reactors | 5 pages, 4 pdf figures, v2 more backgrounds included, typos fixed | JHEP 1601 (2016) 004 | 10.1007/JHEP01(2016)004 | null | hep-ph physics.acc-ph physics.ins-det | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Accelerator driven system (ADS) subcritical nuclear reactors are under
development around the world. They will be intense sources of free, 30-50 MeV
antimuon decay at rest antimuon neutrinos. These ADS reactor neutrinos can
provide a robust test of the LSND anomaly and a precise measurement of the
leptonic CP-violating phase delta, including sign(cos(delta)). The first phase
of many ADS programs includes the construction of a low energy, high intensity
proton or deuteron accelerator, which can yield competitive bounds on sterile
neutrinos.
| [
{
"created": "Fri, 11 Sep 2015 13:13:22 GMT",
"version": "v1"
},
{
"created": "Sun, 15 Nov 2015 03:50:42 GMT",
"version": "v2"
}
] | 2017-04-27 | [
[
"Ciuffoli",
"Emilio",
""
],
[
"Evslin",
"Jarah",
""
],
[
"Zhao",
"Fengyi",
""
]
] | Accelerator driven system (ADS) subcritical nuclear reactors are under development around the world. They will be intense sources of free, 30-50 MeV antimuon decay at rest antimuon neutrinos. These ADS reactor neutrinos can provide a robust test of the LSND anomaly and a precise measurement of the leptonic CP-violating phase delta, including sign(cos(delta)). The first phase of many ADS programs includes the construction of a low energy, high intensity proton or deuteron accelerator, which can yield competitive bounds on sterile neutrinos. |
hep-ph/0110122 | Carlos Munoz | Shaaban Khalil and Carlos Munoz | The Enigma of the Dark Matter | Invited review article for the journal Contemporary Physics. The
level is suitable for researchers which are non-specialists in the subject,
and also for students. Latex, 20 pages, 5 figures | Contemp.Phys. 43 (2002) 51-62 | 10.1080/00107510110102290 | IPPP/01/40, DCPT/01/80, FTUAM 01/19, IFT-UAM/CSIC-01-29 | hep-ph astro-ph hep-th physics.pop-ph | null | One of the great scientific enigmas still unsolved, the existence of dark
matter, is reviewed. Simple gravitational arguments imply that most of the mass
in the Universe, at least 90%, is some (unknown) non-luminous matter. Some
particle candidates for dark matter are discussed with particular emphasis on
the neutralino, a particle predicted by the supersymmetric extension of the
Standard Model of particle physics. Experiments searching for these relic
particles, carried out by many groups around the world, are also discussed.
These experiments are becoming more sensitive every year and in fact one of the
collaborations claims that the first direct evidence for dark matter has
already been observed.
| [
{
"created": "Tue, 9 Oct 2001 13:25:48 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Khalil",
"Shaaban",
""
],
[
"Munoz",
"Carlos",
""
]
] | One of the great scientific enigmas still unsolved, the existence of dark matter, is reviewed. Simple gravitational arguments imply that most of the mass in the Universe, at least 90%, is some (unknown) non-luminous matter. Some particle candidates for dark matter are discussed with particular emphasis on the neutralino, a particle predicted by the supersymmetric extension of the Standard Model of particle physics. Experiments searching for these relic particles, carried out by many groups around the world, are also discussed. These experiments are becoming more sensitive every year and in fact one of the collaborations claims that the first direct evidence for dark matter has already been observed. |
1405.1264 | Arun Prasath V | Arun Prasath, Rohini M. Godbole, Saurabh D. Rindani | Longitudinal top polarisation measurement and anomalous $Wtb$ coupling | significantly revised version, clarifications on the term
'polarisation' added, new references added, the title modified, 41 figures.
Accepted for publication in EPJ C | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Kinematical distributions of decay products of the top quark carry
information on the polarisation of the top as well as on any possible new
physics in the decay of the top quark. We construct observables in the form of
asymmetries in the kinematical distributions to probe their effects.
Charged-lepton angular distributions in the decay are insensitive to anomalous
couplings to leading order. Hence these can be a robust probe of top
polarisation. However, these are difficult to measure in the case of highly
boosted top quarks as compared to energy distributions of decay products. These
are then sensitive, in general, to both top polarisation and top anomalous
couplings. We compare various asymmetries for their sensitivities to the
longitudinal polarisation of the top quark as well as to possible new physics
in the $Wtb$ vertex, paying special attention to the case of highly boosted top
quarks. We perform a $\chi ^2$- analysis to determine the regions in the
longitudinal polarisation of the top quark and the couplings of the $Wtb$
vertex constrained by different combinations of the asymmetries. Moreover, we
find that use of observables sensitive to the longitudinal top polarisation can
add to the sensitivity to which the $Wtb$ vertex can be probed.
| [
{
"created": "Tue, 6 May 2014 13:29:26 GMT",
"version": "v1"
},
{
"created": "Tue, 9 Dec 2014 13:39:10 GMT",
"version": "v2"
},
{
"created": "Thu, 13 Aug 2015 20:33:39 GMT",
"version": "v3"
}
] | 2015-08-17 | [
[
"Prasath",
"Arun",
""
],
[
"Godbole",
"Rohini M.",
""
],
[
"Rindani",
"Saurabh D.",
""
]
] | Kinematical distributions of decay products of the top quark carry information on the polarisation of the top as well as on any possible new physics in the decay of the top quark. We construct observables in the form of asymmetries in the kinematical distributions to probe their effects. Charged-lepton angular distributions in the decay are insensitive to anomalous couplings to leading order. Hence these can be a robust probe of top polarisation. However, these are difficult to measure in the case of highly boosted top quarks as compared to energy distributions of decay products. These are then sensitive, in general, to both top polarisation and top anomalous couplings. We compare various asymmetries for their sensitivities to the longitudinal polarisation of the top quark as well as to possible new physics in the $Wtb$ vertex, paying special attention to the case of highly boosted top quarks. We perform a $\chi ^2$- analysis to determine the regions in the longitudinal polarisation of the top quark and the couplings of the $Wtb$ vertex constrained by different combinations of the asymmetries. Moreover, we find that use of observables sensitive to the longitudinal top polarisation can add to the sensitivity to which the $Wtb$ vertex can be probed. |
hep-ph/9906481 | Naotoshi Okamura | N. Haba (Ohio State Univ. and Mie Univ.) and N. Okamura (Theory Group,
KEK) | Stability of the Lepton-Flavor Mixing Matrix Against Quantum Corrections | 37 pages, 24 figures, 6 tables | Eur.Phys.J.C14:347-365,2000 | 10.1007/s100520000333 | OHSTPY-HEP-T-99-013, KEK-TH-632 | hep-ph | null | Recent neutrino experiments suggest the strong evidences of tiny neutrino
masses and the lepton-flavor mixing. Neutrino-oscillation solutions for the
atmospheric neutrino anomaly and the solar neutrino deficit can determine the
texture of neutrino mass matrix according to the neutrino mass hierarchies as
Type A: m_3 \gg m_2 \sim m_1, Type B: m_3 \ll m_2 \sim m_1, and Type C: m_3
\sim m_2 \sim m_1. In this paper we study the stability of the lepton-flavor
mixing matrix against quantum corrections for all types of mass hierarchy in
the minimal supersymmetric Standard Model with the effective dimension-five
operator which gives Majorana masses of neutrinos. The relative sign
assignments of neutrino masses in each type play the crucial roles for the
stability against quantum corrections. We find the lepton-flavor mixing matrix
of Type A is stable against quantum corrections, and that of Type B with the
same (opposite) signs of m_1 and m_2 are unstable (stable). For Type C, the
lepton-flavor-mixing matrix approaches to the definite unitary matrix according
to the relative sign assignments of neutrino mass eigenvalues, as the effects
of quantum corrections become large enough to neglect squared mass differences
of neutrinos.
| [
{
"created": "Thu, 24 Jun 1999 13:25:11 GMT",
"version": "v1"
}
] | 2011-09-13 | [
[
"Haba",
"N.",
"",
"Ohio State Univ. and Mie Univ."
],
[
"Okamura",
"N.",
"",
"Theory Group,\n KEK"
]
] | Recent neutrino experiments suggest the strong evidences of tiny neutrino masses and the lepton-flavor mixing. Neutrino-oscillation solutions for the atmospheric neutrino anomaly and the solar neutrino deficit can determine the texture of neutrino mass matrix according to the neutrino mass hierarchies as Type A: m_3 \gg m_2 \sim m_1, Type B: m_3 \ll m_2 \sim m_1, and Type C: m_3 \sim m_2 \sim m_1. In this paper we study the stability of the lepton-flavor mixing matrix against quantum corrections for all types of mass hierarchy in the minimal supersymmetric Standard Model with the effective dimension-five operator which gives Majorana masses of neutrinos. The relative sign assignments of neutrino masses in each type play the crucial roles for the stability against quantum corrections. We find the lepton-flavor mixing matrix of Type A is stable against quantum corrections, and that of Type B with the same (opposite) signs of m_1 and m_2 are unstable (stable). For Type C, the lepton-flavor-mixing matrix approaches to the definite unitary matrix according to the relative sign assignments of neutrino mass eigenvalues, as the effects of quantum corrections become large enough to neglect squared mass differences of neutrinos. |
2011.02493 | Aria Radick | Aria Radick, Anna-Maria Taki, Tien-Tien Yu | Dependence of Dark Matter - Electron Scattering on the Galactic Dark
Matter Velocity Distribution | 21+6 pages, 2 appendices, 13 figures, 4 tables | null | 10.1088/1475-7516/2021/02/004 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The rate of dark matter-electron scattering depends on the underlying
velocity distribution of the dark matter halo. Importantly, dark
matter-electron scattering is particularly sensitive to the high-velocity tail,
which differs significantly amongst the various dark matter halo models. In
this work, we summarize the leading halo models and discuss the various
parameters which enter them. We recommend updated values for these parameters
based on recent studies and measurements. Furthermore, we quantify the
dependence of the dark matter-electron scattering rate on the choice of halo
model and parameters, and demonstrate how these choices propagate to the
predicted cross-section limits. The rate is most sensitive to changes in the
circular velocity v0; in silicon targets, we find that the changes in the rate
predictions can range from O(0.01%) to O(100%) for contact interactions and
O(10%) to O(100%) for long-range interactions.
| [
{
"created": "Wed, 4 Nov 2020 19:00:03 GMT",
"version": "v1"
}
] | 2021-02-17 | [
[
"Radick",
"Aria",
""
],
[
"Taki",
"Anna-Maria",
""
],
[
"Yu",
"Tien-Tien",
""
]
] | The rate of dark matter-electron scattering depends on the underlying velocity distribution of the dark matter halo. Importantly, dark matter-electron scattering is particularly sensitive to the high-velocity tail, which differs significantly amongst the various dark matter halo models. In this work, we summarize the leading halo models and discuss the various parameters which enter them. We recommend updated values for these parameters based on recent studies and measurements. Furthermore, we quantify the dependence of the dark matter-electron scattering rate on the choice of halo model and parameters, and demonstrate how these choices propagate to the predicted cross-section limits. The rate is most sensitive to changes in the circular velocity v0; in silicon targets, we find that the changes in the rate predictions can range from O(0.01%) to O(100%) for contact interactions and O(10%) to O(100%) for long-range interactions. |
hep-ph/9601269 | Oscar J. P. Eboli | Oscar J. P. Eboli, F. de Campos, J. Rosiek, and J. W. F. Valle | Searching for Invisibly Decaying Higgs Bosons at LEP II | 22 pages, latex, uses epsfig.sty, 5 figures | Phys.Rev.D55:1316-1325,1997 | 10.1103/PhysRevD.55.1316 | FTUV/95-68, IFIC/95-71, KA-TP-12-1995, MADPH-96-925 | hep-ph | null | We study the potential of LEP II to unravel the existence of invisibly
decaying Higgs bosons, predicted in a wide class of models. We perform a model
independent analysis, focusing our attention to the final state topologies
exhibiting $b \bar{b}$ or $\ell^+ \ell^-$ ($\ell=\mu$ or $e$) pairs and missing
energy. We carefully evaluate the signals and backgrounds, choosing appropriate
cuts to enhance the discovery limits. Our results demonstrate that LEP II is
capable of discovering such a Higgs boson for a wide range of masses and
couplings.
| [
{
"created": "Mon, 15 Jan 1996 17:24:27 GMT",
"version": "v1"
}
] | 2009-09-17 | [
[
"Eboli",
"Oscar J. P.",
""
],
[
"de Campos",
"F.",
""
],
[
"Rosiek",
"J.",
""
],
[
"Valle",
"J. W. F.",
""
]
] | We study the potential of LEP II to unravel the existence of invisibly decaying Higgs bosons, predicted in a wide class of models. We perform a model independent analysis, focusing our attention to the final state topologies exhibiting $b \bar{b}$ or $\ell^+ \ell^-$ ($\ell=\mu$ or $e$) pairs and missing energy. We carefully evaluate the signals and backgrounds, choosing appropriate cuts to enhance the discovery limits. Our results demonstrate that LEP II is capable of discovering such a Higgs boson for a wide range of masses and couplings. |
hep-ph/0101159 | D. R. T. Jones | D.R.T. Jones | Anomaly Mediated Supersymmetry Breaking, D-terms and R-symmetry | 10 pages, LaTeX. Invited talk at RADCOR 2000, Carmel, Sept. 2000 | null | null | LTH 492 | hep-ph | null | We explore two distinct resolutions to the tachyonic slepton puzzle in the
Anomaly Mediated Supersymmetry Breaking scenario. Both are based on extending
the MSSM by an anomaly free U(1) symmetry, and in both cases exact RG
invariance is preserved.
| [
{
"created": "Mon, 15 Jan 2001 16:42:26 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Jones",
"D. R. T.",
""
]
] | We explore two distinct resolutions to the tachyonic slepton puzzle in the Anomaly Mediated Supersymmetry Breaking scenario. Both are based on extending the MSSM by an anomaly free U(1) symmetry, and in both cases exact RG invariance is preserved. |
1308.6521 | Sergei Gninenko | S.N. Gninenko | Search for MeV dark photons in a light-shining-through-walls experiment
at CERN | 10 pages, 7 figures. Discussion on a sensitive search for the A'->
invisible decay added. This work is continued in arXiv:1312.3309. To appear
in PRD | Phys.Rev. D89 (2014) 075008 | 10.1103/PhysRevD.89.075008 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In addition to gravity, there might be another very weak interaction between
the ordinary and dark matter transmitted by U'(1) gauge bosons A' (dark
photons) mixing with our photons. If such A's exist, they could be searched for
in a light-shining-through-a-wall experiment with a high energy electron beam.
The electron energy absorption in a calorimeter (CAL1) is accompanied by the
emission of bremsstrahlung A's in the reaction eZ -> eZA' of electrons
scattering on nuclei due to the \gamma - A' mixing. A part of the primary beam
energy is deposited in the CAL1, while the rest of the energy is transmitted by
the A' through the "CAL1 wall" and deposited in another downstream calorimeter
CAL2 by the e+e- pair from the A'->e+e- decay in flight. Thus, the A's could be
observed by looking for an excess of events with the two-shower signature
generated by a single high energy electron in the CAL1 and CAL2. A proposal to
perform such an experiment to probe the still unexplored area of the mixing
strength 10^{-5} < \epsilon < 10^{-3} and masses M_{A'} < 100 MeV by using
10-300 GeV electron beams from the CERN SPS is presented. The experiment can
provide complementary coverage of the parameter space, which is intended to be
probed by other searches. It has also a capability for a sensitive search for
A's decaying invisibly to dark-sector particles, such as dark matter, which
could cover a significant part of the still allowed parameter space.
| [
{
"created": "Thu, 29 Aug 2013 17:01:25 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Sep 2013 05:58:15 GMT",
"version": "v2"
},
{
"created": "Sat, 22 Mar 2014 13:45:31 GMT",
"version": "v3"
}
] | 2014-04-09 | [
[
"Gninenko",
"S. N.",
""
]
] | In addition to gravity, there might be another very weak interaction between the ordinary and dark matter transmitted by U'(1) gauge bosons A' (dark photons) mixing with our photons. If such A's exist, they could be searched for in a light-shining-through-a-wall experiment with a high energy electron beam. The electron energy absorption in a calorimeter (CAL1) is accompanied by the emission of bremsstrahlung A's in the reaction eZ -> eZA' of electrons scattering on nuclei due to the \gamma - A' mixing. A part of the primary beam energy is deposited in the CAL1, while the rest of the energy is transmitted by the A' through the "CAL1 wall" and deposited in another downstream calorimeter CAL2 by the e+e- pair from the A'->e+e- decay in flight. Thus, the A's could be observed by looking for an excess of events with the two-shower signature generated by a single high energy electron in the CAL1 and CAL2. A proposal to perform such an experiment to probe the still unexplored area of the mixing strength 10^{-5} < \epsilon < 10^{-3} and masses M_{A'} < 100 MeV by using 10-300 GeV electron beams from the CERN SPS is presented. The experiment can provide complementary coverage of the parameter space, which is intended to be probed by other searches. It has also a capability for a sensitive search for A's decaying invisibly to dark-sector particles, such as dark matter, which could cover a significant part of the still allowed parameter space. |
hep-ph/9712239 | Lavignac | Nikolaos Irges and St\'ephane Lavignac | A Guide to Flat Direction Analysis in Anomalous U(1) Models | 15 pages, LaTeX2e | Phys.Lett. B424 (1998) 293-304 | 10.1016/S0370-2693(98)00197-X | UFIFT-HEP-97-34 | hep-ph | null | We suggest a systematic procedure to study D- and F-flat directions in a
large class of models with an anomalous U(1). This class of models is
characterized by the existence of a vacuum that breaks all Abelian gauge
symmetries connecting the observable sector to the hidden sector. We show that,
under some conditions, there is no other stable vacuum that breaks these
symmetries. As a consequence, the model yields definite (order of magnitude)
predictions for low-energy mass hierarchies. Then we study generic flat
directions and identify the ones that may lead to undesirable vacua. We give
necessary conditions for those to be lifted, and show that supersymmetry
breaking only slightly affects the conclusions from the flat direction
analysis.
| [
{
"created": "Wed, 3 Dec 1997 00:45:39 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Irges",
"Nikolaos",
""
],
[
"Lavignac",
"Stéphane",
""
]
] | We suggest a systematic procedure to study D- and F-flat directions in a large class of models with an anomalous U(1). This class of models is characterized by the existence of a vacuum that breaks all Abelian gauge symmetries connecting the observable sector to the hidden sector. We show that, under some conditions, there is no other stable vacuum that breaks these symmetries. As a consequence, the model yields definite (order of magnitude) predictions for low-energy mass hierarchies. Then we study generic flat directions and identify the ones that may lead to undesirable vacua. We give necessary conditions for those to be lifted, and show that supersymmetry breaking only slightly affects the conclusions from the flat direction analysis. |
1509.00026 | Guy D. Moore | Leesa Fleury and Guy D. Moore | Axion dark matter: strings and their cores | 23 pages plus appendices, 17 figures | null | 10.1088/1475-7516/2016/01/004 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Axions constitute a well-motivated dark matter candidate, and if PQ symmetry
breaking occurred after inflation, it should be possible to make a clean
prediction for the relation between the axion mass and the axion dark matter
density. We show that axion (or other global) string networks in 3D have a
network density that depends logarithmically on the string separation-to-core
ratio. This logarithm would be about 10 times larger in axion cosmology than
what we can achieve in numerical simulations. We simulate axion production in
the early Universe, finding that, for the separation-to-core ratios we can
achieve, the changing density of the network has little impact on the axion
production efficiency.
| [
{
"created": "Mon, 31 Aug 2015 20:15:08 GMT",
"version": "v1"
}
] | 2016-01-13 | [
[
"Fleury",
"Leesa",
""
],
[
"Moore",
"Guy D.",
""
]
] | Axions constitute a well-motivated dark matter candidate, and if PQ symmetry breaking occurred after inflation, it should be possible to make a clean prediction for the relation between the axion mass and the axion dark matter density. We show that axion (or other global) string networks in 3D have a network density that depends logarithmically on the string separation-to-core ratio. This logarithm would be about 10 times larger in axion cosmology than what we can achieve in numerical simulations. We simulate axion production in the early Universe, finding that, for the separation-to-core ratios we can achieve, the changing density of the network has little impact on the axion production efficiency. |
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