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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2008.08468 | Eleftheria Malami | Eleftheria Malami | Exploring New Physics in $B \rightarrow \pi K$ Decays | 10 pages, 5 figures, Corfu Summer Institute 2019 "School and
Workshops on Elementary Particle Physics and Gravity" (CORFU2019) - Workshop
on Connecting Insights in Fundamental Physics: Standard Model and Beyond | null | 10.22323/1.376.0025 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | B-meson decays play an important role in flavour physics. The $B \rightarrow
\pi K$ decays are dominated by QCD loop diagrams (penguins) but also
electroweak penguins, where New Physics may enter, have a significant impact on
the decay amplitude. Since measurements from B-factories indicate deviations
from the Standard Model picture, we perform a state-of-the-art analysis to
explore the correlation of the CP asymmetries and to get an updated picture. We
propose a strategy for the optimal determination of the parameters which
describe electroweak penguin effects and apply it to current data, utilising
both neutral and charged $B \rightarrow \pi K$ decays. This new method can be
fully exploited at the future Belle-II experiment, which will hopefully answer
the question: Do these decays imply New Physics?
| [
{
"created": "Wed, 19 Aug 2020 14:15:32 GMT",
"version": "v1"
},
{
"created": "Mon, 24 Aug 2020 12:08:54 GMT",
"version": "v2"
}
] | 2020-08-25 | [
[
"Malami",
"Eleftheria",
""
]
] | B-meson decays play an important role in flavour physics. The $B \rightarrow \pi K$ decays are dominated by QCD loop diagrams (penguins) but also electroweak penguins, where New Physics may enter, have a significant impact on the decay amplitude. Since measurements from B-factories indicate deviations from the Standard Model picture, we perform a state-of-the-art analysis to explore the correlation of the CP asymmetries and to get an updated picture. We propose a strategy for the optimal determination of the parameters which describe electroweak penguin effects and apply it to current data, utilising both neutral and charged $B \rightarrow \pi K$ decays. This new method can be fully exploited at the future Belle-II experiment, which will hopefully answer the question: Do these decays imply New Physics? |
1812.02778 | Jure Zupan | Wolfgang Altmannshofer, Michele Tammaro, Jure Zupan | Non-standard neutrino interactions and low energy experiments | 42 pages + appendices, 13 figures | null | 10.1007/JHEP09(2019)083 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We formulate an Effective Field Theory (EFT) for Non Standard neutrino
Interactions (NSI) in elastic scattering with light quarks, leptons, gluons and
photons, including all possible operators of dimension 5, 6 and 7. We provide
the expressions for the cross sections in coherent neutrino-nucleus scattering
and in deep inelastic scattering. Assuming single operator dominance we
constrain the respective Wilson coefficient using the measurements by the
COHERENT and CHARM collaborations. We also point out the constraining power of
future elastic neutrino-nucleus scattering experiments. Finally, we explore the
implications of the bounds for SMEFT operators above the electroweak breaking
scale.
| [
{
"created": "Thu, 6 Dec 2018 20:06:26 GMT",
"version": "v1"
}
] | 2019-10-23 | [
[
"Altmannshofer",
"Wolfgang",
""
],
[
"Tammaro",
"Michele",
""
],
[
"Zupan",
"Jure",
""
]
] | We formulate an Effective Field Theory (EFT) for Non Standard neutrino Interactions (NSI) in elastic scattering with light quarks, leptons, gluons and photons, including all possible operators of dimension 5, 6 and 7. We provide the expressions for the cross sections in coherent neutrino-nucleus scattering and in deep inelastic scattering. Assuming single operator dominance we constrain the respective Wilson coefficient using the measurements by the COHERENT and CHARM collaborations. We also point out the constraining power of future elastic neutrino-nucleus scattering experiments. Finally, we explore the implications of the bounds for SMEFT operators above the electroweak breaking scale. |
2212.13302 | Johann (Jan) Rafelski | Jan Rafelski (Arizona) and Michal Petran | QCD phase transition studied by means of hadron production | 11 pages, many figures; Presented in Wroclaw at the February 2014
MB32-Symposium honoring Ludwik Turko | Physics of Particles and Nuclei {\bf 46} (5) pp 748-755 (2015) | 10.1134/S1063779615050238 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | This is a brief review of our work describing the hadronization process of a
QGP fireball formed in relativistic heavy-ion collisions. We introduce the
SHARE method of analysis of hadron multiplicities. Using this tool we describe
in consistent continuos manner the yield of all hadrons produced in the
available range of reaction energies and centralities. The properties of the
fireball final state can be understood by considering all primary hadronic
particles. The dense hadron fireball created at SPS, RHIC, and LHC shows that
the final state is differentiated solely by: i) volume changes; and ii) flavor
(strangeness, charm) content. Conversely, emerging particles add up to create
universal hadronization pressure $P = 80 \pm 3$ MeV/fm$^3$ for all considered
collision systems. The relative strangeness to entropy content of a large
fireball is found to be that of quark-gluon plasma degrees of freedom near the
chemical QGP equilibrium. This 'Universal Hadronization' condition common to
SPS, RHIC, and LHC agrees with the proposed reaction picture of a direct QGP
fireball evaporation into free-streaming hadrons.
| [
{
"created": "Mon, 26 Dec 2022 21:32:51 GMT",
"version": "v1"
}
] | 2022-12-29 | [
[
"Rafelski",
"Jan",
"",
"Arizona"
],
[
"Petran",
"Michal",
""
]
] | This is a brief review of our work describing the hadronization process of a QGP fireball formed in relativistic heavy-ion collisions. We introduce the SHARE method of analysis of hadron multiplicities. Using this tool we describe in consistent continuos manner the yield of all hadrons produced in the available range of reaction energies and centralities. The properties of the fireball final state can be understood by considering all primary hadronic particles. The dense hadron fireball created at SPS, RHIC, and LHC shows that the final state is differentiated solely by: i) volume changes; and ii) flavor (strangeness, charm) content. Conversely, emerging particles add up to create universal hadronization pressure $P = 80 \pm 3$ MeV/fm$^3$ for all considered collision systems. The relative strangeness to entropy content of a large fireball is found to be that of quark-gluon plasma degrees of freedom near the chemical QGP equilibrium. This 'Universal Hadronization' condition common to SPS, RHIC, and LHC agrees with the proposed reaction picture of a direct QGP fireball evaporation into free-streaming hadrons. |
1711.02116 | Rikkert Frederix | Rikkert Frederix and Davide Pagani and Marco Zaro | Large NLO corrections in $t\bar{t}W^{\pm}$ and $t\bar{t}t\bar{t}$
hadroproduction from supposedly subleading EW contributions | 40 pages, 8 figures; v2: published version with minor changes w.r.t
original submission | null | 10.1007/JHEP02(2018)031 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the complete-NLO predictions for $t\bar{t}W^{\pm}$ and
$t\bar{t}t\bar{t}$ production in proton--proton collisions at 13 and 100 TeV.
All the non-vanishing contributions of $\mathcal{O}(\alpha_s^i \alpha^j)$ with
$i+j=3,4$ for $t\bar{t}W^{\pm}$ and $i+j=4,5$ for $t\bar{t}t\bar{t}$ are
evaluated without any approximation. For $t\bar{t}W^{\pm}$ we find that, due to
the presence of $tW \to tW$ scattering, at 13(100) TeV the
$\mathcal{O}(\alpha_s \alpha^3)$ contribution is about 12(70)\% of the LO,
i.e., it is larger than the so-called NLO EW corrections (the
$\mathcal{O}(\alpha_s^2 \alpha^2)$ terms) and has opposite sign. In the case of
$t\bar{t}t\bar{t}$ production, large contributions from electroweak $tt \to tt$
scattering are already present at LO in the $\mathcal{O}(\alpha_s^3 \alpha)$
and $\mathcal{O}(\alpha_s^2 \alpha^2)$ terms. For the same reason we find that
both NLO terms of $\mathcal{O}(\alpha_s^4 \alpha)$, i.e., the NLO EW
corrections, and $\mathcal{O}(\alpha_s^3 \alpha^2)$ are large ($\pm 15 \%$ of
the LO) and their relative contributions strongly depend on the values of the
renormalisation and factorisation scales. However, large accidental
cancellations are present (away from the threshold region) between these two
contributions. Moreover, the NLO corrections strongly depend on the kinematics
and are particularly large at the threshold, where even the relative
contribution from $\mathcal{O}(\alpha_s^2 \alpha^3)$ terms amounts to tens of
percents.
| [
{
"created": "Mon, 6 Nov 2017 19:11:23 GMT",
"version": "v1"
},
{
"created": "Fri, 9 Feb 2018 14:49:00 GMT",
"version": "v2"
}
] | 2018-04-04 | [
[
"Frederix",
"Rikkert",
""
],
[
"Pagani",
"Davide",
""
],
[
"Zaro",
"Marco",
""
]
] | We calculate the complete-NLO predictions for $t\bar{t}W^{\pm}$ and $t\bar{t}t\bar{t}$ production in proton--proton collisions at 13 and 100 TeV. All the non-vanishing contributions of $\mathcal{O}(\alpha_s^i \alpha^j)$ with $i+j=3,4$ for $t\bar{t}W^{\pm}$ and $i+j=4,5$ for $t\bar{t}t\bar{t}$ are evaluated without any approximation. For $t\bar{t}W^{\pm}$ we find that, due to the presence of $tW \to tW$ scattering, at 13(100) TeV the $\mathcal{O}(\alpha_s \alpha^3)$ contribution is about 12(70)\% of the LO, i.e., it is larger than the so-called NLO EW corrections (the $\mathcal{O}(\alpha_s^2 \alpha^2)$ terms) and has opposite sign. In the case of $t\bar{t}t\bar{t}$ production, large contributions from electroweak $tt \to tt$ scattering are already present at LO in the $\mathcal{O}(\alpha_s^3 \alpha)$ and $\mathcal{O}(\alpha_s^2 \alpha^2)$ terms. For the same reason we find that both NLO terms of $\mathcal{O}(\alpha_s^4 \alpha)$, i.e., the NLO EW corrections, and $\mathcal{O}(\alpha_s^3 \alpha^2)$ are large ($\pm 15 \%$ of the LO) and their relative contributions strongly depend on the values of the renormalisation and factorisation scales. However, large accidental cancellations are present (away from the threshold region) between these two contributions. Moreover, the NLO corrections strongly depend on the kinematics and are particularly large at the threshold, where even the relative contribution from $\mathcal{O}(\alpha_s^2 \alpha^3)$ terms amounts to tens of percents. |
2302.10542 | Kruteesh Desai | Kruteesh Desai and Ruohan Li and Stephan Meighen-Berger | Searching for Dark Matter Annihilation with IceCube and P-ONE | We updated the IceCube results with updated J-factor especially the
table | null | 10.1088/1475-7516/2024/02/049 | null | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a new search for weakly interacting massive particles utilizing
ten years of public IceCube data, setting more stringent bounds than previous
IceCube analysis on massive dark matter to neutrino annihilation. We also
predict the future potential of the new neutrino observatory, P-ONE, showing
that it may even exceed the sensitivities of gamma-ray searches by about 1-2
orders of magnitude in 1-10 TeV regions. This analysis considers the diffuse
dark matter self-annihilation to neutrinos via direct and indirect channels,
from the galactic dark matter halo and extra-galactic sources. We also predict
that P-ONE will be capable of pushing these bounds further than IceCube, even
reaching the thermal relic abundance utilizing a galactic center search for
extended run-time.
| [
{
"created": "Tue, 21 Feb 2023 09:15:34 GMT",
"version": "v1"
},
{
"created": "Thu, 16 Mar 2023 09:59:50 GMT",
"version": "v2"
},
{
"created": "Wed, 12 Apr 2023 16:29:08 GMT",
"version": "v3"
},
{
"created": "Wed, 19 Apr 2023 15:21:05 GMT",
"version": "v4"
},
{
"c... | 2024-03-12 | [
[
"Desai",
"Kruteesh",
""
],
[
"Li",
"Ruohan",
""
],
[
"Meighen-Berger",
"Stephan",
""
]
] | We present a new search for weakly interacting massive particles utilizing ten years of public IceCube data, setting more stringent bounds than previous IceCube analysis on massive dark matter to neutrino annihilation. We also predict the future potential of the new neutrino observatory, P-ONE, showing that it may even exceed the sensitivities of gamma-ray searches by about 1-2 orders of magnitude in 1-10 TeV regions. This analysis considers the diffuse dark matter self-annihilation to neutrinos via direct and indirect channels, from the galactic dark matter halo and extra-galactic sources. We also predict that P-ONE will be capable of pushing these bounds further than IceCube, even reaching the thermal relic abundance utilizing a galactic center search for extended run-time. |
hep-ph/9511447 | null | Gautam Bhattacharyya (CERN) | LEP- and low energy-bounds on R-parity-violating supersymmetric Yukawa
couplings | 2 pages, postscript (uucompressed), to appear in the Proceedings of
the International Europhysics Conference on High Energy Physics, Brussels, 27
July - 2 August, 1995 | null | null | null | hep-ph | null | Electroweak precision data at LEP are used to place bounds on some
$\lambda'$-type ($L$-violating) and $\lambda''$-type ($B$-violating) $R$-parity
violating supersymmetric Yukawa couplings. We consider one-loop corrections
(triangles and self-energies) induced by these couplings to the $Z$-partial
widths. The couplings involving the top quark induce stronger loop effects and
hence are more strongly constrained than others. On the other hand, information
on $D$- and $\tau$-decays are used to constrain some of the $\lambda'$-type
couplings which are complementary to the ones constrained from LEP. Among the
bounds we have derived, many are new from a phenomenological view-point.
| [
{
"created": "Wed, 29 Nov 1995 08:42:38 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Bhattacharyya",
"Gautam",
"",
"CERN"
]
] | Electroweak precision data at LEP are used to place bounds on some $\lambda'$-type ($L$-violating) and $\lambda''$-type ($B$-violating) $R$-parity violating supersymmetric Yukawa couplings. We consider one-loop corrections (triangles and self-energies) induced by these couplings to the $Z$-partial widths. The couplings involving the top quark induce stronger loop effects and hence are more strongly constrained than others. On the other hand, information on $D$- and $\tau$-decays are used to constrain some of the $\lambda'$-type couplings which are complementary to the ones constrained from LEP. Among the bounds we have derived, many are new from a phenomenological view-point. |
1212.2636 | Charlotte Strege | C. Strege, G. Bertone, F. Feroz, M. Fornasa, R. Ruiz de Austri and R.
Trotta | Global Fits of the cMSSM and NUHM including the LHC Higgs discovery and
new XENON100 constraints | 37 pages, 11 figures, submitted to JCAP | JCAP04(2013)013 | 10.1088/1475-7516/2013/04/013 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present global fits of the constrained Minimal Supersymmetric Standard
Model (cMSSM) and the Non-Universal Higgs Model (NUHM), including the most
recent CMS constraint on the Higgs boson mass, 5.8/fb integrated luminosity
null Supersymmetry searches by ATLAS, the new LHCb measurement of the Bs to
mu+mu- branching ratio and the 7-year WMAP dark matter relic abundance
determination. We include the latest dark matter constraints from the XENON100
experiment, marginalising over astrophysical and particle physics
uncertainties. We present Bayesian posterior and profile likelihood maps of the
highest resolution available today, obtained from up to 350M points. We find
that the new constraint on the Higgs boson mass has a dramatic impact, ruling
out large regions of previously favoured cMSSM and NUHM parameter space. In the
cMSSM, light sparticles and predominantly gaugino-like dark matter with a mass
of a few hundred GeV are favoured. The NUHM exhibits a strong preference for
heavier sparticle masses and a Higgsino-like neutralino with a mass of 1 TeV.
The future ton-scale XENON1T direct detection experiment will probe large
portions of the currently favoured cMSSM and NUHM parameter space. The LHC
operating at 14 TeV collision energy will explore the favoured regions in the
cMSSM, while most of the regions favoured in the NUHM will remain inaccessible.
Our best-fit points achieve a satisfactory quality-of-fit, with p-values
ranging from 0.21 to 0.35, so that none of the two models studied can be
presently excluded at any meaningful significance level.
| [
{
"created": "Tue, 11 Dec 2012 21:00:03 GMT",
"version": "v1"
}
] | 2014-04-28 | [
[
"Strege",
"C.",
""
],
[
"Bertone",
"G.",
""
],
[
"Feroz",
"F.",
""
],
[
"Fornasa",
"M.",
""
],
[
"de Austri",
"R. Ruiz",
""
],
[
"Trotta",
"R.",
""
]
] | We present global fits of the constrained Minimal Supersymmetric Standard Model (cMSSM) and the Non-Universal Higgs Model (NUHM), including the most recent CMS constraint on the Higgs boson mass, 5.8/fb integrated luminosity null Supersymmetry searches by ATLAS, the new LHCb measurement of the Bs to mu+mu- branching ratio and the 7-year WMAP dark matter relic abundance determination. We include the latest dark matter constraints from the XENON100 experiment, marginalising over astrophysical and particle physics uncertainties. We present Bayesian posterior and profile likelihood maps of the highest resolution available today, obtained from up to 350M points. We find that the new constraint on the Higgs boson mass has a dramatic impact, ruling out large regions of previously favoured cMSSM and NUHM parameter space. In the cMSSM, light sparticles and predominantly gaugino-like dark matter with a mass of a few hundred GeV are favoured. The NUHM exhibits a strong preference for heavier sparticle masses and a Higgsino-like neutralino with a mass of 1 TeV. The future ton-scale XENON1T direct detection experiment will probe large portions of the currently favoured cMSSM and NUHM parameter space. The LHC operating at 14 TeV collision energy will explore the favoured regions in the cMSSM, while most of the regions favoured in the NUHM will remain inaccessible. Our best-fit points achieve a satisfactory quality-of-fit, with p-values ranging from 0.21 to 0.35, so that none of the two models studied can be presently excluded at any meaningful significance level. |
1101.0069 | Akbari Jahan | Akbari Jahan and D. K. Choudhury | Fractal Inspired Models of Quark and Gluon Distributions and
Longitudinal Structure Function FL(x, Q2) at small x | 11 pages, 4 figures, Accepted for publication on 10-07-2010 in Indian
Journal of Physics | Ind. J. Phys. 85 (2011) 587 | 10.1007/s12648-011-0061-3 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In recent years, Fractal Inspired Models of quark and gluon densities at
small x have been proposed. In this paper, we investigate longitudinal
structure function F-L (x, Q2) within this approach. We make predictions using
the QCD based approximate relation between the longitudinal structure function
and the gluon density. As the Altarelli-Martinelli equation for the
longitudinal structure function cannot be applied to Model I due to the
presence of a singularity in the Bjorken x-space we consider Model II only. The
qualitative feature of the prediction of Model II is found to be compatible
with the QCD expectation.
| [
{
"created": "Thu, 30 Dec 2010 11:30:53 GMT",
"version": "v1"
}
] | 2014-04-28 | [
[
"Jahan",
"Akbari",
""
],
[
"Choudhury",
"D. K.",
""
]
] | In recent years, Fractal Inspired Models of quark and gluon densities at small x have been proposed. In this paper, we investigate longitudinal structure function F-L (x, Q2) within this approach. We make predictions using the QCD based approximate relation between the longitudinal structure function and the gluon density. As the Altarelli-Martinelli equation for the longitudinal structure function cannot be applied to Model I due to the presence of a singularity in the Bjorken x-space we consider Model II only. The qualitative feature of the prediction of Model II is found to be compatible with the QCD expectation. |
1308.4736 | A. H. Rezaeian | Amir H. Rezaeian | Comparison of the Color Glass Condensate to multiplicity dependence of
the average transverse momentum in p+p, p+Pb and Pb+Pb collisions at the LHC | 11 pages, 9 figures; v2: predictions are extended to large N_ch, two
new plots added. The version to appear in PLB | Phys.Lett.B727:218-225,2013 | 10.1016/j.physletb.2013.10.038 | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The first moment <p_T> of the charged-particle transverse momentum spectrum
and its correlation with the charged-particle multiplicity N_{ch} provide vital
information about the underlying particle production mechanism. The ALICE
collaboration recently reported that <p_T> versus N_{ch} in Pb+Pb collisions is
smaller than in p+p and p+Pb collisions. Other interesting features of data is
rather flatness of <p_T> at high N_{ch} in Pb+Pb and p+Pb collisions in
seemingly striking contrast to the case of p+p collisions. With a detailed
calculation, we show all these peculiar features in a wide range of energies
and system sizes can be well described by the idea of gluon saturation within
the Color Glass Condensate framework using the k_T-factorization. This
establishes an important fact that the bulk of the produced particles in
heavy-ion collisions at the LHC carries signature of the initial stage of
collisions. We also show that the recent scaling property seen by the CMS
collaboration between the number of tracks in p+p and p+Pb collisions may
provide a strong evidence in favor of geometric-scaling phenomenon and gluon
saturation, indicating that the underlying dynamics of high multiplicity events
in p+p and p+Pb collisions should be similar.
| [
{
"created": "Wed, 21 Aug 2013 23:19:02 GMT",
"version": "v1"
},
{
"created": "Tue, 15 Oct 2013 20:02:43 GMT",
"version": "v2"
}
] | 2013-11-11 | [
[
"Rezaeian",
"Amir H.",
""
]
] | The first moment <p_T> of the charged-particle transverse momentum spectrum and its correlation with the charged-particle multiplicity N_{ch} provide vital information about the underlying particle production mechanism. The ALICE collaboration recently reported that <p_T> versus N_{ch} in Pb+Pb collisions is smaller than in p+p and p+Pb collisions. Other interesting features of data is rather flatness of <p_T> at high N_{ch} in Pb+Pb and p+Pb collisions in seemingly striking contrast to the case of p+p collisions. With a detailed calculation, we show all these peculiar features in a wide range of energies and system sizes can be well described by the idea of gluon saturation within the Color Glass Condensate framework using the k_T-factorization. This establishes an important fact that the bulk of the produced particles in heavy-ion collisions at the LHC carries signature of the initial stage of collisions. We also show that the recent scaling property seen by the CMS collaboration between the number of tracks in p+p and p+Pb collisions may provide a strong evidence in favor of geometric-scaling phenomenon and gluon saturation, indicating that the underlying dynamics of high multiplicity events in p+p and p+Pb collisions should be similar. |
1909.03548 | Philip D. Mannheim | Philip D. Mannheim | Equivalence of light-front quantization and instant-time quantization | 21 pages. Paper now includes: Use of the Lehmann representation to
establish equivalence of instant-time and light-front commutators to all
orders, and an analytic relation between instant-time and light-front
Hamiltonians. Also note change in title of paper | Phys. Rev. D 102, 025020 (2020) | 10.1103/PhysRevD.102.025020 | null | hep-ph hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Commutation or anticommutation relations quantized at equal instant time and
commutation or anticommutation relations quantized at equal light-front time
not only cannot be transformed into each other, they take completely different
forms. While they would thus appear to describe different theories, we show
that this is not in fact the case. By looking not at equal times but at unequal
times, we show that unequal instant-time commutation or anticommutation
relations are completely equivalent to unequal light-front time commutation or
anticommutation relations. Light-front quantization and instant-time
quantization are thus the same, with it being only the restriction to equal
times that makes them look different. However for fermions there is a caveat,
as the light-front anticommutation relations involve projection operators
acting on the fermion fields. Nonetheless, not only can one still derive
fermion unequal light-front time anticommutators starting from unequal
instant-time ones, one can even derive unequal instant-time fermion
anticommutators starting from unequal light-front time anticommutators even
though the fermion projection operators that are relevant in the light-front
case are not invertible. To establish the equivalence for gauge fields we
present a quantization procedure that does not involve zero-mode singularities
that are commonly encountered in light-front gauge field studies. We also study
time-ordered products of fields, and again show the equivalence despite the
fact that there are additional terms in the fermion light-front case. We
establish our results first for free theories, and then to all orders in
interacting theories though comparison of the instant-time and light-front
Lehmann representations. Finally, we compare instant-time Hamiltonians and
light-front Hamiltonians, and show that in the instant-time rest frame they
give identical results.
| [
{
"created": "Sun, 8 Sep 2019 21:38:09 GMT",
"version": "v1"
},
{
"created": "Wed, 22 Jan 2020 14:57:11 GMT",
"version": "v2"
},
{
"created": "Mon, 15 Jun 2020 17:59:19 GMT",
"version": "v3"
}
] | 2020-07-29 | [
[
"Mannheim",
"Philip D.",
""
]
] | Commutation or anticommutation relations quantized at equal instant time and commutation or anticommutation relations quantized at equal light-front time not only cannot be transformed into each other, they take completely different forms. While they would thus appear to describe different theories, we show that this is not in fact the case. By looking not at equal times but at unequal times, we show that unequal instant-time commutation or anticommutation relations are completely equivalent to unequal light-front time commutation or anticommutation relations. Light-front quantization and instant-time quantization are thus the same, with it being only the restriction to equal times that makes them look different. However for fermions there is a caveat, as the light-front anticommutation relations involve projection operators acting on the fermion fields. Nonetheless, not only can one still derive fermion unequal light-front time anticommutators starting from unequal instant-time ones, one can even derive unequal instant-time fermion anticommutators starting from unequal light-front time anticommutators even though the fermion projection operators that are relevant in the light-front case are not invertible. To establish the equivalence for gauge fields we present a quantization procedure that does not involve zero-mode singularities that are commonly encountered in light-front gauge field studies. We also study time-ordered products of fields, and again show the equivalence despite the fact that there are additional terms in the fermion light-front case. We establish our results first for free theories, and then to all orders in interacting theories though comparison of the instant-time and light-front Lehmann representations. Finally, we compare instant-time Hamiltonians and light-front Hamiltonians, and show that in the instant-time rest frame they give identical results. |
hep-ph/0203233 | Stefan Antusch | Stefan Antusch, Joern Kersten, Manfred Lindner, Michael Ratz | Neutrino Mass Matrix Running for Non-Degenerate See-Saw Scales | 12 pages, 9 figures | Phys.Lett. B538 (2002) 87-95 | 10.1016/S0370-2693(02)01960-3 | TUM-HEP-459/02 | hep-ph | null | We consider the running of the neutrino mass matrix in the Standard Model and
the Minimal Supersymmetric Standard Model, extended by heavy singlet Majorana
neutrinos. Unlike previous studies, we do not assume that all of the heavy mass
eigenvalues are degenerate. This leads to various effective theories when the
heavy degrees of freedom are integrated out successively. We calculate the
Renormalization Group Equations that govern the evolution of the neutrino mass
matrix in these effective theories. We show that an appropriate treatment of
the singlet mass scales can yield a substantially different result compared to
integrating out the singlets at a common intermediate scale.
| [
{
"created": "Mon, 25 Mar 2002 15:37:59 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Antusch",
"Stefan",
""
],
[
"Kersten",
"Joern",
""
],
[
"Lindner",
"Manfred",
""
],
[
"Ratz",
"Michael",
""
]
] | We consider the running of the neutrino mass matrix in the Standard Model and the Minimal Supersymmetric Standard Model, extended by heavy singlet Majorana neutrinos. Unlike previous studies, we do not assume that all of the heavy mass eigenvalues are degenerate. This leads to various effective theories when the heavy degrees of freedom are integrated out successively. We calculate the Renormalization Group Equations that govern the evolution of the neutrino mass matrix in these effective theories. We show that an appropriate treatment of the singlet mass scales can yield a substantially different result compared to integrating out the singlets at a common intermediate scale. |
1905.08644 | Jing-Yu Zhu | Zhi-zhong Xing, Jing-yu Zhu | Sum rules and asymptotic behaviors of neutrino mixing in dense matter | 21 pages, 2 figures, version accepted by Nuclear Physics B | null | 10.1016/j.nuclphysb.2019.114803 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has proved convenient to define the effective lepton flavor mixing matrix
$\widetilde{U}$ and neutrino mass-squared differences
$\widetilde{\Delta}^{}_{ji} \equiv \widetilde{m}^2_j - \widetilde{m}^2_i$ (for
$i,j =1,2,3$) to describe the phenomena of neutrino mixing and flavor
oscillations in a medium, but the prerequisite is to establish direct and
transparent relations between these effective quantities and their fundamental
counterparts in vacuum. With the help of two sets of sum rules for
$\widetilde{U}$ and $\widetilde{\Delta}^{}_{ji}$, we derive new and exact
formulas for moduli of the nine elements of $\widetilde{U}$ and the sides of
its three Dirac unitarity triangles in the complex plane. The asymptotic
behaviors of $|\widetilde{U}^{}_{\alpha i}|^2$ and $\widetilde{\Delta}^{}_{ji}$
(for $\alpha = e, \mu, \tau$ and $i,j =1,2,3$) in very dense matter (namely,
allowing the matter parameter $A = 2\sqrt{2} ~ G^{}_{\rm F} N^{}_e E$ to
mathematically approach infinity) are analytically unraveled for the first
time, and in this connection the confusion associated with the parameter
redundancy of $\widetilde{\theta}^{}_{12}$, $\widetilde{\theta}^{}_{13}$,
$\widetilde{\theta}^{}_{23}$ and $\widetilde{\delta}$ in the standard
parametrization of $\widetilde{U}$ is clarified.
| [
{
"created": "Tue, 21 May 2019 13:57:55 GMT",
"version": "v1"
},
{
"created": "Mon, 14 Oct 2019 08:24:43 GMT",
"version": "v2"
}
] | 2020-01-08 | [
[
"Xing",
"Zhi-zhong",
""
],
[
"Zhu",
"Jing-yu",
""
]
] | It has proved convenient to define the effective lepton flavor mixing matrix $\widetilde{U}$ and neutrino mass-squared differences $\widetilde{\Delta}^{}_{ji} \equiv \widetilde{m}^2_j - \widetilde{m}^2_i$ (for $i,j =1,2,3$) to describe the phenomena of neutrino mixing and flavor oscillations in a medium, but the prerequisite is to establish direct and transparent relations between these effective quantities and their fundamental counterparts in vacuum. With the help of two sets of sum rules for $\widetilde{U}$ and $\widetilde{\Delta}^{}_{ji}$, we derive new and exact formulas for moduli of the nine elements of $\widetilde{U}$ and the sides of its three Dirac unitarity triangles in the complex plane. The asymptotic behaviors of $|\widetilde{U}^{}_{\alpha i}|^2$ and $\widetilde{\Delta}^{}_{ji}$ (for $\alpha = e, \mu, \tau$ and $i,j =1,2,3$) in very dense matter (namely, allowing the matter parameter $A = 2\sqrt{2} ~ G^{}_{\rm F} N^{}_e E$ to mathematically approach infinity) are analytically unraveled for the first time, and in this connection the confusion associated with the parameter redundancy of $\widetilde{\theta}^{}_{12}$, $\widetilde{\theta}^{}_{13}$, $\widetilde{\theta}^{}_{23}$ and $\widetilde{\delta}$ in the standard parametrization of $\widetilde{U}$ is clarified. |
hep-ph/9702324 | Nicolao Fornengo | N. Fornengo, C.W. Kim and J. Song (The Johns Hopkins University,
Baltimore, USA, INFN, Sezione di Torino, Italy and Korean Institute for
Advanced Study, Seoul, Korea) | Finite temperature effects on the neutrino decoupling in the early
Universe | 18 pages, LaTeX (uses RevTeX), 6 figures added as PS files, submitted
to Phys.Rev.D | Phys.Rev. D56 (1997) 5123-5134 | 10.1103/PhysRevD.56.5123 | JHU-TIPAC 97003, DFTT 15/97, KIAS-P97002 | hep-ph | null | Leading finite temperature effects on the neutrino decoupling temperature in
the early Universe have been studied. We have incorporated modifications of the
dispersion relation and the phase space distribution due to the presence of
particles in the heat bath at temperature around MeV. Since both the expansion
rate of the Universe and the interaction rate of a neutrino are reduced by
finite temperature effects, it is necessary to calculate thermal corrections as
precisely as possible in order to find the net effect on the neutrino
decoupling temperature. We have performed such a calculation by using the
finite temperature field theory. It has been shown that the finite temperature
effects increase the neutrino decoupling temperature by 4.4%, the largest
contribution coming from the modification of the phase space due to the thermal
bath.
| [
{
"created": "Thu, 13 Feb 1997 12:21:27 GMT",
"version": "v1"
}
] | 2009-10-30 | [
[
"Fornengo",
"N.",
"",
"The Johns Hopkins University,\n Baltimore, USA, INFN, Sezione di Torino, Italy and Korean Institute for\n Advanced Study, Seoul, Korea"
],
[
"Kim",
"C. W.",
"",
"The Johns Hopkins University,\n Baltimore, USA, INFN, Sezione di Torino, Italy and Korean ... | Leading finite temperature effects on the neutrino decoupling temperature in the early Universe have been studied. We have incorporated modifications of the dispersion relation and the phase space distribution due to the presence of particles in the heat bath at temperature around MeV. Since both the expansion rate of the Universe and the interaction rate of a neutrino are reduced by finite temperature effects, it is necessary to calculate thermal corrections as precisely as possible in order to find the net effect on the neutrino decoupling temperature. We have performed such a calculation by using the finite temperature field theory. It has been shown that the finite temperature effects increase the neutrino decoupling temperature by 4.4%, the largest contribution coming from the modification of the phase space due to the thermal bath. |
hep-ph/0505038 | Eduardo De Rafael | Samuel Friot (CPT, LM-Orsay), David Greynat (CPT), Eduardo de Rafael
(CPT) | Asymptotics of Feynman Diagrams and The Mellin-Barnes Representation | References added. This is the version published in Physics Letters B | Phys.Lett. B628 (2005) 73-84 | 10.1016/j.physletb.2005.08.126 | CPT-2005/P020 | hep-ph hep-th | null | It is shown that the integral representation of Feynman diagrams in terms of
the traditional Feynman parameters, when combined with properties of the
Mellin--Barnes representation and the so called {\it converse mapping theorem},
provide a very simple and efficient way to obtain the analytic asymptotic
behaviours in both the large and small ratios of mass scales.
| [
{
"created": "Thu, 5 May 2005 19:04:42 GMT",
"version": "v1"
},
{
"created": "Thu, 7 Jul 2005 05:12:13 GMT",
"version": "v2"
},
{
"created": "Thu, 25 Aug 2005 12:49:19 GMT",
"version": "v3"
}
] | 2009-11-11 | [
[
"Friot",
"Samuel",
"",
"CPT, LM-Orsay"
],
[
"Greynat",
"David",
"",
"CPT"
],
[
"de Rafael",
"Eduardo",
"",
"CPT"
]
] | It is shown that the integral representation of Feynman diagrams in terms of the traditional Feynman parameters, when combined with properties of the Mellin--Barnes representation and the so called {\it converse mapping theorem}, provide a very simple and efficient way to obtain the analytic asymptotic behaviours in both the large and small ratios of mass scales. |
1312.6181 | Stephen Godfrey | Stephen Godfrey and Ian T. Jardine (Carleton University) | Comment on the Nature of the $D_{s1}^*(2710)$ and $D_{sJ}^*(2860)$
Mesons | 8 pages, 2 figures | Phys. Rev. D 89, 074023 (2014) | 10.1103/PhysRevD.89.074023 | null | hep-ph hep-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Two charm-strange mesons, the $D_{s1}^*(2710)$ and the $D_{sJ}^*(2860)$, have
recently been observed by several experiments. There has been speculation in
the literature that the $D_{s1}^*(2710)$ is the $2^3S_1(c\bar{s})$ state and
the $D_{sJ}^*(2860)$ is the $1^3D_1(c\bar{s})$ state. In this paper we explore
this and other explanations in the context of the relativized quark model and
the pseudoscalar emission decay model. We conclude that the $D_{s1}^*(2710)$ is
most likely the $1^3D_1 (c\bar{s})$ state and the $D_{sJ}^*(2860)$ is most
likely the $1^3D_3 (c\bar{s})$ state with the $1D_2$ resonances also
contributing to the observed signals and explaining the observed ratios of
branching ratios to $D^*K$ and $DK$ final states. We point out that measuring
the $D_{sJ}^*(2860)$ spin can support or eliminate this explanation and that
there are six excited $D_s$ states in this mass region; the $2^3S_1$, $2^1S_0$,
$1^3D_1$, $1^3D_3$ and two $1D_2$ states. Observing some of the missing states
would help confirm the nature of the $D_{s1}^*(2710)$ and the $D_{sJ}^*(2860)$
states.
| [
{
"created": "Sat, 21 Dec 2013 00:37:19 GMT",
"version": "v1"
},
{
"created": "Tue, 11 Mar 2014 18:26:36 GMT",
"version": "v2"
}
] | 2014-04-23 | [
[
"Godfrey",
"Stephen",
"",
"Carleton University"
],
[
"Jardine",
"Ian T.",
"",
"Carleton University"
]
] | Two charm-strange mesons, the $D_{s1}^*(2710)$ and the $D_{sJ}^*(2860)$, have recently been observed by several experiments. There has been speculation in the literature that the $D_{s1}^*(2710)$ is the $2^3S_1(c\bar{s})$ state and the $D_{sJ}^*(2860)$ is the $1^3D_1(c\bar{s})$ state. In this paper we explore this and other explanations in the context of the relativized quark model and the pseudoscalar emission decay model. We conclude that the $D_{s1}^*(2710)$ is most likely the $1^3D_1 (c\bar{s})$ state and the $D_{sJ}^*(2860)$ is most likely the $1^3D_3 (c\bar{s})$ state with the $1D_2$ resonances also contributing to the observed signals and explaining the observed ratios of branching ratios to $D^*K$ and $DK$ final states. We point out that measuring the $D_{sJ}^*(2860)$ spin can support or eliminate this explanation and that there are six excited $D_s$ states in this mass region; the $2^3S_1$, $2^1S_0$, $1^3D_1$, $1^3D_3$ and two $1D_2$ states. Observing some of the missing states would help confirm the nature of the $D_{s1}^*(2710)$ and the $D_{sJ}^*(2860)$ states. |
hep-ph/9903453 | Hai-Yang Cheng | Yaw-Hwang Chen, Hai-Yang Cheng, B. Tseng, Kwei-Chou Yang | Charmless Hadronic Two-body Decays of B_u and B_d Mesons | 72 pages, 14 figures. Data are updated; new discussions are added to
sec.2. To appear in Phys. Rev | Phys. Rev. D 60, 094014 (1999) | 10.1103/PhysRevD.60.094014 | IP-ASTP-01-99 | hep-ph hep-ex | null | Two-body charmless nonleptonic decays of B_u and B_d mesons are studied
within the framework of generalized factorization in which the effective Wilson
coefficients $c^{eff}_i$ are renormalization-scale and -scheme independent
while factorization is applied to the tree-level hadronic matrix elements.
Contrary to previous studies, our $c_i^{eff}$ do not suffer from gauge and
infrared problems. Nonfactorizable effects are parametrized in terms of N_c(LL)
and N_c(LR), the effective numbers of colors arising from (V-A)(V-A) and
(V-A)(V+A) four-quark operators, respectively. Tree and penguin transitions are
classified into six different classes. The data of $B^-\to\rho^0\pi^-$ and
$B^-\to\phi K^-$ clearly indicate that $N_c(LR)\neq N_c(LL)$: The first
measurement of the b -> u mode $B^-\to\rho^0\pi^-$ and the experimental
information on the tree-dominated mode $B^-\to\omega\pi^-$ all imply that
Nc(LL) is less than 3, whereas the CLEO measurement of $B^-\to\phi K^-$ shows
Nc(LR)>3. For given input parameters, the prediction of ${\cal B}(B\to\eta' K)$
is largely improved by setting Nc(LL)~2 and Nc(LR)>Nc(LL); in particular, the
charm content of the eta' contributes in the right direction. The decay rate of
$B\to\phi K^*$ is very sensitive to the form-factor ratio A_2/A_1; the absence
of $B\to\phi K$ events does not necessarily invalidate the factorization
approach. If the branching ratio of $B^-\to\omega K^-$ is experimentally found
to be significantly larger than that of $B^-\to\rho^0 K^-$, we argue that
inelastic final-state rescattering may account for the disparity between
$\omega K^-$ and $\rho^0 K^-$.
| [
{
"created": "Tue, 23 Mar 1999 23:12:11 GMT",
"version": "v1"
},
{
"created": "Sat, 3 Jul 1999 05:59:21 GMT",
"version": "v2"
}
] | 2016-08-25 | [
[
"Chen",
"Yaw-Hwang",
""
],
[
"Cheng",
"Hai-Yang",
""
],
[
"Tseng",
"B.",
""
],
[
"Yang",
"Kwei-Chou",
""
]
] | Two-body charmless nonleptonic decays of B_u and B_d mesons are studied within the framework of generalized factorization in which the effective Wilson coefficients $c^{eff}_i$ are renormalization-scale and -scheme independent while factorization is applied to the tree-level hadronic matrix elements. Contrary to previous studies, our $c_i^{eff}$ do not suffer from gauge and infrared problems. Nonfactorizable effects are parametrized in terms of N_c(LL) and N_c(LR), the effective numbers of colors arising from (V-A)(V-A) and (V-A)(V+A) four-quark operators, respectively. Tree and penguin transitions are classified into six different classes. The data of $B^-\to\rho^0\pi^-$ and $B^-\to\phi K^-$ clearly indicate that $N_c(LR)\neq N_c(LL)$: The first measurement of the b -> u mode $B^-\to\rho^0\pi^-$ and the experimental information on the tree-dominated mode $B^-\to\omega\pi^-$ all imply that Nc(LL) is less than 3, whereas the CLEO measurement of $B^-\to\phi K^-$ shows Nc(LR)>3. For given input parameters, the prediction of ${\cal B}(B\to\eta' K)$ is largely improved by setting Nc(LL)~2 and Nc(LR)>Nc(LL); in particular, the charm content of the eta' contributes in the right direction. The decay rate of $B\to\phi K^*$ is very sensitive to the form-factor ratio A_2/A_1; the absence of $B\to\phi K$ events does not necessarily invalidate the factorization approach. If the branching ratio of $B^-\to\omega K^-$ is experimentally found to be significantly larger than that of $B^-\to\rho^0 K^-$, we argue that inelastic final-state rescattering may account for the disparity between $\omega K^-$ and $\rho^0 K^-$. |
hep-ph/0307323 | Anthony Zee | A. Zee | Parametrizing the Neutrino Mixing Matrix | 9 pages | Phys.Rev. D68 (2003) 093002 | 10.1103/PhysRevD.68.093002 | null | hep-ph | null | We propose parametrizations of the neutrino mixing matrix. We discuss several
Ansatzes: in some of them $V_{e3}=0$ but in others $V_{e3}$ typically ``comes
out'' to be of order $\simeq 0.05.$
| [
{
"created": "Fri, 25 Jul 2003 22:43:42 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Zee",
"A.",
""
]
] | We propose parametrizations of the neutrino mixing matrix. We discuss several Ansatzes: in some of them $V_{e3}=0$ but in others $V_{e3}$ typically ``comes out'' to be of order $\simeq 0.05.$ |
1009.5870 | Yufeng Li | Y.F. Li and Zhi-zhong Xing | Possible Capture of keV Sterile Neutrino Dark Matter on Radioactive
beta-decaying Nuclei | 14 pages, 3 figures, more discussions and references added. To appear
in PLB | Phys.Lett.B695:205-210,2011 | 10.1016/j.physletb.2010.11.015 | null | hep-ph astro-ph.CO hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | There exists an observed "desert" spanning six orders of magnitude between
O(0.5) eV and O(0.5) MeV in the fermion mass spectrum. We argue that it might
accommodate one or more keV sterile neutrinos as a natural candidate for warm
dark matter. To illustrate this point of view, we simply assume that there is
one keV sterile neutrino nu_4 and its flavor eigenstate nu_s weakly mixes with
three active neutrinos. We clarify different active-sterile neutrino mixing
factors for the radiative decay of nu_4 and beta decays in a self-consistent
parametrization. A direct detection of this keV sterile neutrino dark matter in
the laboratory is in principle possible since the nu_4 component of nu_e can
leave a distinct imprint on the electron energy spectrum when it is captured on
radioactive beta-decaying nuclei. We carry out an analysis of its signatures in
the capture reactions nu_e + ^{3}H \to ^{3}He + e^- and nu_e + ^{106}Ru \to
^{106}Rh + e^- against the beta-decay backgrounds, and conclude that this
experimental approach might not be hopeless in the long run.
| [
{
"created": "Wed, 29 Sep 2010 12:56:09 GMT",
"version": "v1"
},
{
"created": "Fri, 5 Nov 2010 11:35:21 GMT",
"version": "v2"
}
] | 2011-02-25 | [
[
"Li",
"Y. F.",
""
],
[
"Xing",
"Zhi-zhong",
""
]
] | There exists an observed "desert" spanning six orders of magnitude between O(0.5) eV and O(0.5) MeV in the fermion mass spectrum. We argue that it might accommodate one or more keV sterile neutrinos as a natural candidate for warm dark matter. To illustrate this point of view, we simply assume that there is one keV sterile neutrino nu_4 and its flavor eigenstate nu_s weakly mixes with three active neutrinos. We clarify different active-sterile neutrino mixing factors for the radiative decay of nu_4 and beta decays in a self-consistent parametrization. A direct detection of this keV sterile neutrino dark matter in the laboratory is in principle possible since the nu_4 component of nu_e can leave a distinct imprint on the electron energy spectrum when it is captured on radioactive beta-decaying nuclei. We carry out an analysis of its signatures in the capture reactions nu_e + ^{3}H \to ^{3}He + e^- and nu_e + ^{106}Ru \to ^{106}Rh + e^- against the beta-decay backgrounds, and conclude that this experimental approach might not be hopeless in the long run. |
1605.00654 | Vedran Brdar | Carlos A. Arg\"uelles, Vedran Brdar, Joachim Kopp | Production of keV Sterile Neutrinos in Supernovae: New Constraints and
Gamma Ray Observables | 10 pages, 9 figures. Matches version published in PRD | Phys. Rev. D 99, 043012 (2019) | 10.1103/PhysRevD.99.043012 | MITP/16-034 | hep-ph astro-ph.HE | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the production of sterile neutrinos in supernovae, focusing in
particular on the keV--MeV mass range, which is the most interesting range if
sterile neutrinos are to account for the dark matter in the Universe. Focusing
on the simplest scenario in which sterile neutrinos mixes only with muon or tau
neutrino, we argue that the production of keV--MeV sterile neutrinos can be
strongly enhanced by a Mikheyev--Smirnov--Wolfenstein (MSW) resonance, so that
a substantial flux is expected to emerge from a supernova, even if vacuum
mixing angles between active and sterile neutrinos are tiny. Using energetics
arguments, this yields limits on the sterile neutrino parameter space that
reach down to mixing angles of the order of $\sin^2 2\theta \lesssim 10^{-14}$
and are up to an order of magnitude stronger than those from X-ray
observations. While supernova limits suffer from larger systematic
uncertainties than X-ray limits they apply also to scenarios in which sterile
neutrinos are not abundantly produced in the early Universe. We also compute
the flux of $\mathcal{O}(\text{MeV})$ photons expected from the decay of
sterile neutrinos produced in supernovae, but find that it is beyond current
observational reach even for a nearby supernova.
| [
{
"created": "Mon, 2 May 2016 20:00:04 GMT",
"version": "v1"
},
{
"created": "Sun, 3 Mar 2019 19:27:50 GMT",
"version": "v2"
}
] | 2019-03-05 | [
[
"Argüelles",
"Carlos A.",
""
],
[
"Brdar",
"Vedran",
""
],
[
"Kopp",
"Joachim",
""
]
] | We study the production of sterile neutrinos in supernovae, focusing in particular on the keV--MeV mass range, which is the most interesting range if sterile neutrinos are to account for the dark matter in the Universe. Focusing on the simplest scenario in which sterile neutrinos mixes only with muon or tau neutrino, we argue that the production of keV--MeV sterile neutrinos can be strongly enhanced by a Mikheyev--Smirnov--Wolfenstein (MSW) resonance, so that a substantial flux is expected to emerge from a supernova, even if vacuum mixing angles between active and sterile neutrinos are tiny. Using energetics arguments, this yields limits on the sterile neutrino parameter space that reach down to mixing angles of the order of $\sin^2 2\theta \lesssim 10^{-14}$ and are up to an order of magnitude stronger than those from X-ray observations. While supernova limits suffer from larger systematic uncertainties than X-ray limits they apply also to scenarios in which sterile neutrinos are not abundantly produced in the early Universe. We also compute the flux of $\mathcal{O}(\text{MeV})$ photons expected from the decay of sterile neutrinos produced in supernovae, but find that it is beyond current observational reach even for a nearby supernova. |
1912.07587 | Fabrizio Rompineve | Benedict von Harling, Alex Pomarol, Oriol Pujolas and Fabrizio
Rompineve | Peccei-Quinn Phase Transition at LIGO | 27 pages, 7 figure. v2: references added | null | 10.1007/JHEP04(2020)195 | null | hep-ph astro-ph.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The LIGO observatories can potentially detect stochastic gravitational waves
arising from phase transitions which happened in the early universe at
temperatures around $T\sim 10^{8}$ GeV. This provides an extraordinary
opportunity for discovering the phase transition associated with the breaking
of the Peccei-Quinn symmetry, required in QCD axion models. Here we consider
the simplest Peccei-Quinn models and study under which conditions a strong
first-order phase transition can occur, analyzing its associated gravitational
wave signal. To be detectable at LIGO, we show that some supercooling is
needed, which can arise either in Coleman-Weinberg-type symmetry breaking or in
strongly-coupled models. We also investigate phase transitions that
interestingly proceed by first breaking the electroweak symmetry at large
scales before tunneling to the Peccei-Quinn breaking vacuum. In this case, the
associated gravitational wave signal is more likely to be probed at the
proposed Einstein Telescope.
| [
{
"created": "Mon, 16 Dec 2019 18:57:10 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Apr 2020 15:39:40 GMT",
"version": "v2"
}
] | 2020-05-20 | [
[
"von Harling",
"Benedict",
""
],
[
"Pomarol",
"Alex",
""
],
[
"Pujolas",
"Oriol",
""
],
[
"Rompineve",
"Fabrizio",
""
]
] | The LIGO observatories can potentially detect stochastic gravitational waves arising from phase transitions which happened in the early universe at temperatures around $T\sim 10^{8}$ GeV. This provides an extraordinary opportunity for discovering the phase transition associated with the breaking of the Peccei-Quinn symmetry, required in QCD axion models. Here we consider the simplest Peccei-Quinn models and study under which conditions a strong first-order phase transition can occur, analyzing its associated gravitational wave signal. To be detectable at LIGO, we show that some supercooling is needed, which can arise either in Coleman-Weinberg-type symmetry breaking or in strongly-coupled models. We also investigate phase transitions that interestingly proceed by first breaking the electroweak symmetry at large scales before tunneling to the Peccei-Quinn breaking vacuum. In this case, the associated gravitational wave signal is more likely to be probed at the proposed Einstein Telescope. |
2001.06488 | Hannes Jung | A. Bermudez Martinez, P.L.S. Connor, D. Dominguez Damiani, L.I.
Estevez Banos, F. Hautmann, H. Jung, J. Lidrych, A. Lelek, M. Mendizabal, M.
Schmitz, S. Taheri Monfared, Q. Wang, T. Wening, H. Yang, R. Zlebcik | The transverse momentum spectrum of low mass Drell-Yan production at
next-to-leading order in the parton branching method | v2: references, clarifications and discussion added; results
unchanged Version to appear in EPJC | null | null | DESY 20-006 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | It has been observed in the literature that measurements of low-mass
Drell-Yan (DY) transverse momentum spectra at low center-of-mass energies
$\sqrt{s}$ are not well described by perturbative QCD calculations in collinear
factorization in the region where transverse momenta are comparable with the DY
mass. We examine this issue from the standpoint of the Parton Branching (PB)
method, combining next-to-leading-order (NLO) calculations of the hard process
with the evolution of transverse momentum dependent (TMD) parton distributions.
We compare our predictions with experimental measurements at low DY mass, and
find very good agreement.In addition we use the low mass DY measurements at low
$\sqrt{s}$ to determine the width $q_s$ of the intrinsic Gauss distribution of
the PB-TMDs at low evolution scales. We find values close to what has earlier
been used in applications of PB -TMDs to high-energy processes at the Large
Hadron Collider (LHC) and HERA. We find that at low DY mass and low $\sqrt{s}$
even in the region of $p_t/m_{DY} \sim 1$ the contribution of multiple soft
gluon emissions (included in the PB-TMDs) is essential to describe
themeasurements, while at larger masses ($m_{DY} \sim m_{Z}$) and LHC energies
the contribution from soft gluons in the region of $p_t/m_{DY}\sim 1$ is small.
| [
{
"created": "Fri, 17 Jan 2020 16:33:41 GMT",
"version": "v1"
},
{
"created": "Sun, 14 Jun 2020 13:58:10 GMT",
"version": "v2"
}
] | 2020-06-16 | [
[
"Martinez",
"A. Bermudez",
""
],
[
"Connor",
"P. L. S.",
""
],
[
"Damiani",
"D. Dominguez",
""
],
[
"Banos",
"L. I. Estevez",
""
],
[
"Hautmann",
"F.",
""
],
[
"Jung",
"H.",
""
],
[
"Lidrych",
"J.",
""
],... | It has been observed in the literature that measurements of low-mass Drell-Yan (DY) transverse momentum spectra at low center-of-mass energies $\sqrt{s}$ are not well described by perturbative QCD calculations in collinear factorization in the region where transverse momenta are comparable with the DY mass. We examine this issue from the standpoint of the Parton Branching (PB) method, combining next-to-leading-order (NLO) calculations of the hard process with the evolution of transverse momentum dependent (TMD) parton distributions. We compare our predictions with experimental measurements at low DY mass, and find very good agreement.In addition we use the low mass DY measurements at low $\sqrt{s}$ to determine the width $q_s$ of the intrinsic Gauss distribution of the PB-TMDs at low evolution scales. We find values close to what has earlier been used in applications of PB -TMDs to high-energy processes at the Large Hadron Collider (LHC) and HERA. We find that at low DY mass and low $\sqrt{s}$ even in the region of $p_t/m_{DY} \sim 1$ the contribution of multiple soft gluon emissions (included in the PB-TMDs) is essential to describe themeasurements, while at larger masses ($m_{DY} \sim m_{Z}$) and LHC energies the contribution from soft gluons in the region of $p_t/m_{DY}\sim 1$ is small. |
hep-ph/0010170 | Steve R. Blattnig | Steve R. Blattnig, Sudha R. Swaminathan, Adam T. Kruger, Moussa Ngom,
and John W. Norbury | Parametrizations of Inclusive Cross Sections for Pion Production in
Proton-Proton Collisions | 32 pages with 15 figures. Published in Physical Review D62, 094030.
File includes 6 tex files. The main file is paper.tex which has include
statements refering to the rest. figures are in graphs.dir | Phys.Rev.D62:094030,2000 | 10.1103/PhysRevD.62.094030 | null | hep-ph | null | Accurate knowledge of cross sections for pion production in proton-proton
collisions finds wide application in particle physics, astrophysics, cosmic ray
physics and space radiation problems, especially in situations where an
incident proton is transported through some medium, and one requires knowledge
of the output particle spectrum given the input spectrum. In such cases
accurate parametrizations of the cross sections are desired. In this paper we
review much of the experimental data and compare to a wide variety of different
cross section parametrizations. In so doing, we provide parametrizations of
neutral and charged pion cross sections which provide a very accurate
description of the experimental data. Lorentz invariant differential cross
sections, spectral distributions and total cross section parametrizations are
presented.
| [
{
"created": "Mon, 16 Oct 2000 16:26:11 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Blattnig",
"Steve R.",
""
],
[
"Swaminathan",
"Sudha R.",
""
],
[
"Kruger",
"Adam T.",
""
],
[
"Ngom",
"Moussa",
""
],
[
"Norbury",
"John W.",
""
]
] | Accurate knowledge of cross sections for pion production in proton-proton collisions finds wide application in particle physics, astrophysics, cosmic ray physics and space radiation problems, especially in situations where an incident proton is transported through some medium, and one requires knowledge of the output particle spectrum given the input spectrum. In such cases accurate parametrizations of the cross sections are desired. In this paper we review much of the experimental data and compare to a wide variety of different cross section parametrizations. In so doing, we provide parametrizations of neutral and charged pion cross sections which provide a very accurate description of the experimental data. Lorentz invariant differential cross sections, spectral distributions and total cross section parametrizations are presented. |
1007.5489 | James Ferrando | J. Ferrando | DISPred - a program to calculate deep inelastic scattering cross
sections | 11 pages, One figure. this is a manual for the package available at
http://projects.hepforge.org/dispred/ | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new package, DISPred, is described. The package can be used to calculate ep
deep inelastic scattering cross sections at Born level in Electroweak theory
and at both leading and next-to-leading order in QCD.
| [
{
"created": "Fri, 30 Jul 2010 16:22:30 GMT",
"version": "v1"
}
] | 2010-08-02 | [
[
"Ferrando",
"J.",
""
]
] | A new package, DISPred, is described. The package can be used to calculate ep deep inelastic scattering cross sections at Born level in Electroweak theory and at both leading and next-to-leading order in QCD. |
0808.3134 | Mikolaj Misiak | Mikolaj Misiak | QCD Calculations of Radiative B Decays | 6 pages, 4 figures, contribution to the Proceedings of the IXth
International Conference on Heavy Quarks and Leptons (HQL 2008), Melbourne,
Australia, June 5-9, 2008. Note added and refs updated in v2 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The current status of B -> Xs gamma decay rate calculations is summarized.
Missing ingredients at the NNLO level are listed. The global normalization
factor and non-perturbative effects are discussed. Arguments are presented that
results for the cutoff-enhanced perturbative corrections have been misused in
Ref. [15] by applying them in the region E_gamma \in [1.0, 1.6] GeV, which
means that the corresponding numerical effect on BR(B -> Xs gamma, E_gamma >
1.6 GeV) is unreliable.
| [
{
"created": "Fri, 22 Aug 2008 19:49:59 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Mar 2009 22:06:54 GMT",
"version": "v2"
}
] | 2009-03-06 | [
[
"Misiak",
"Mikolaj",
""
]
] | The current status of B -> Xs gamma decay rate calculations is summarized. Missing ingredients at the NNLO level are listed. The global normalization factor and non-perturbative effects are discussed. Arguments are presented that results for the cutoff-enhanced perturbative corrections have been misused in Ref. [15] by applying them in the region E_gamma \in [1.0, 1.6] GeV, which means that the corresponding numerical effect on BR(B -> Xs gamma, E_gamma > 1.6 GeV) is unreliable. |
hep-ph/0209138 | Bo-Qiang Ma | Bo-Wen Xiao, Xin Qian, and Bo-Qiang Ma | The Kaon Form Factor in the Light-Cone Quark Model | 12 latex pages, 2 figures, to appear in Eur.Phy.J.A | Eur.Phys.J. A15 (2002) 523-527 | null | null | hep-ph hep-ex nucl-th | null | The electromagnetic form factor of the kaon meson is calculated in the
light-cone formalism of the relativistic constituent quark model. The
calculated $K^+$ form factor is consistent with almost all of the available
experimental data at low energy scale, while other properties of kaon could
also be interrelated in this representation with reasonable parameters.
Predictions of the form factors for the charged and neutral kaons at higher
energy scale are also given, and we find non-zero $K^0$ form factor at $Q^2 \ne
0$ due to the mass difference between the strange and down quarks inside $K^0$.
| [
{
"created": "Thu, 12 Sep 2002 16:22:58 GMT",
"version": "v1"
},
{
"created": "Fri, 13 Sep 2002 14:29:32 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Xiao",
"Bo-Wen",
""
],
[
"Qian",
"Xin",
""
],
[
"Ma",
"Bo-Qiang",
""
]
] | The electromagnetic form factor of the kaon meson is calculated in the light-cone formalism of the relativistic constituent quark model. The calculated $K^+$ form factor is consistent with almost all of the available experimental data at low energy scale, while other properties of kaon could also be interrelated in this representation with reasonable parameters. Predictions of the form factors for the charged and neutral kaons at higher energy scale are also given, and we find non-zero $K^0$ form factor at $Q^2 \ne 0$ due to the mass difference between the strange and down quarks inside $K^0$. |
hep-ph/0409193 | Gary Prezeau | Gary Pr\'ezeau and Andriy Kurylov | Neutrino mass constraints on $\mu$-decay and $\pi^0\to \nu \bar{\nu}$ | Accepted for publication in PRL | Phys.Rev.Lett. 95 (2005) 101802 | 10.1103/PhysRevLett.95.101802 | null | hep-ph hep-ex | null | In this letter, we show that upper-limits on neutrino mass translate into
upper-limits on the class of neutrino-matter interactions that can generate
loop corrections to the neutrino mass matrix. We apply our results to $\mu$-
and $\pi$-decays and derive model-independent limits on six of the ten
parameters used to parametrize contributions to $\mu$-decay that do not belong
to the standard model.
These upper-limits provide improved constraints on the five Michel
parameters,
$\rho,\xi^\prime,\xi^{\prime\prime},\alpha,\alpha^\prime$, that exceed PDG
constraints by at least one order of magnitude. For $\pi^0\to \nu \bar{\nu}$ we
find for the branching ratio: $B(\pi^0\to\nu \bar\nu) < 10^{-10}$.
| [
{
"created": "Wed, 15 Sep 2004 20:16:25 GMT",
"version": "v1"
},
{
"created": "Mon, 4 Apr 2005 23:05:18 GMT",
"version": "v2"
},
{
"created": "Thu, 28 Jul 2005 20:56:50 GMT",
"version": "v3"
}
] | 2016-08-16 | [
[
"Prézeau",
"Gary",
""
],
[
"Kurylov",
"Andriy",
""
]
] | In this letter, we show that upper-limits on neutrino mass translate into upper-limits on the class of neutrino-matter interactions that can generate loop corrections to the neutrino mass matrix. We apply our results to $\mu$- and $\pi$-decays and derive model-independent limits on six of the ten parameters used to parametrize contributions to $\mu$-decay that do not belong to the standard model. These upper-limits provide improved constraints on the five Michel parameters, $\rho,\xi^\prime,\xi^{\prime\prime},\alpha,\alpha^\prime$, that exceed PDG constraints by at least one order of magnitude. For $\pi^0\to \nu \bar{\nu}$ we find for the branching ratio: $B(\pi^0\to\nu \bar\nu) < 10^{-10}$. |
2009.09727 | Andrea Dubla Dr | Andrea Dubla, Umut G\"ursoy, Raimond Snellings | Charge-dependent flow as evidence of strong electromagnetic fields in
heavy-ion collisions | Invited review from Modern Physics Letter A | MPLA's Volume No. 35, Issue No. 39, Article No. 2050324, Year 2020 | 10.1142/S0217732320503241 | null | hep-ph hep-ex hep-th nucl-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The extremely large electromagnetic fields generated in heavy-ion collisions
provide access to novel observables that are expected to constrain various key
transport properties of the quark-gluon plasma and could help solve one of the
outstanding puzzles in QCD: the strong CP problem. In this review we present a
brief overview of the theoretical and experimental characterization of these
electromagnetic fields. After reviewing the current state, emphasising one of
the observables -- the charge-dependent flow -- we discuss the various
discrepancies between the measurements and theoretical predictions. Finally, to
help resolve the discrepancies, we suggest new measurements and theoretical
ideas.
| [
{
"created": "Mon, 21 Sep 2020 10:03:54 GMT",
"version": "v1"
},
{
"created": "Wed, 28 Oct 2020 12:43:09 GMT",
"version": "v2"
}
] | 2021-01-08 | [
[
"Dubla",
"Andrea",
""
],
[
"Gürsoy",
"Umut",
""
],
[
"Snellings",
"Raimond",
""
]
] | The extremely large electromagnetic fields generated in heavy-ion collisions provide access to novel observables that are expected to constrain various key transport properties of the quark-gluon plasma and could help solve one of the outstanding puzzles in QCD: the strong CP problem. In this review we present a brief overview of the theoretical and experimental characterization of these electromagnetic fields. After reviewing the current state, emphasising one of the observables -- the charge-dependent flow -- we discuss the various discrepancies between the measurements and theoretical predictions. Finally, to help resolve the discrepancies, we suggest new measurements and theoretical ideas. |
1008.0750 | Binur Shaykhatdenov | A.V. Kotikov, V.G.Krivokhizhin, B.G. Shaikhatdenov, and G. Parente | About QCD coupling constant at NNLO from DIS data | 11 pp, 2 figs, contribution to the Proceedings of XLIV PNPI Winter
School held in Roschino (Russia) on 9-14 March, 2010 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We give a brief review of our recent QCD analysis carried out over the deep
inelastic scattering data on F2 structure function and in the non-singlet
approximation to the accuracy up to next-to-next-to-leading-order.
Specifically, analysis was performed over high statistics deep inelastic
scattering data provided by BCDMS, SLAC, NMC and BFP collaborations. For the
coupling constant the following value alpha_s(M_Z^2) = 0.1167 \pm 0.0022 was
found.
| [
{
"created": "Wed, 4 Aug 2010 11:26:25 GMT",
"version": "v1"
}
] | 2010-08-05 | [
[
"Kotikov",
"A. V.",
""
],
[
"Krivokhizhin",
"V. G.",
""
],
[
"Shaikhatdenov",
"B. G.",
""
],
[
"Parente",
"G.",
""
]
] | We give a brief review of our recent QCD analysis carried out over the deep inelastic scattering data on F2 structure function and in the non-singlet approximation to the accuracy up to next-to-next-to-leading-order. Specifically, analysis was performed over high statistics deep inelastic scattering data provided by BCDMS, SLAC, NMC and BFP collaborations. For the coupling constant the following value alpha_s(M_Z^2) = 0.1167 \pm 0.0022 was found. |
hep-ph/0609155 | Zhi-Gang Wang | Z. G. Wang (NCEPU, Baoding) | Analysis of the $\Sigma-n $ form factors with light-cone QCD sum rules | 16 pages, 4 figures, second version, typos corrected, the article is
published in "J. Phys. G34 (2007) 493-504" not in "J. Phys. G34 (2007)
335-346" | J.Phys. G34 (2007) 493-504 | 10.1088/0954-3899/34/3/007 | null | hep-ph | null | In this work, we study the four form-factors $f_1(Q^2)$, $f_2(Q^2)$,
$g_1(Q^2)$ and $g_2(Q^2)$ of the $\Sigma \to n$ in the framework of the
light-cone QCD sum rules approach up to twist-6 three valence quark light-cone
distribution amplitudes. The $f_1(0)$ is the basic input parameter in
extracting the CKM matrix element $|V_{us}|$ from the hyperon decays.
The four form-factors $f_1(Q^2)$, $f_2(Q^2)$, $g_1(Q^2)$ and $g_2(Q^2)$ at
intermediate and large momentum transfers with $Q^2> 3 GeV^2$ have significant
contributions from the end-point (soft) terms. The numerical values of the four
form-factors $f_1(0)$, $f_2(0)$, $g_1(0)$ and $g_2(0)$ are compatible with the
experimental data and theoretical calculations (in magnitude); although the
uncertainties are large.
| [
{
"created": "Sat, 16 Sep 2006 12:07:50 GMT",
"version": "v1"
},
{
"created": "Sat, 11 Nov 2006 08:29:41 GMT",
"version": "v2"
},
{
"created": "Sat, 3 Feb 2007 13:08:17 GMT",
"version": "v3"
}
] | 2007-05-23 | [
[
"Wang",
"Z. G.",
"",
"NCEPU, Baoding"
]
] | In this work, we study the four form-factors $f_1(Q^2)$, $f_2(Q^2)$, $g_1(Q^2)$ and $g_2(Q^2)$ of the $\Sigma \to n$ in the framework of the light-cone QCD sum rules approach up to twist-6 three valence quark light-cone distribution amplitudes. The $f_1(0)$ is the basic input parameter in extracting the CKM matrix element $|V_{us}|$ from the hyperon decays. The four form-factors $f_1(Q^2)$, $f_2(Q^2)$, $g_1(Q^2)$ and $g_2(Q^2)$ at intermediate and large momentum transfers with $Q^2> 3 GeV^2$ have significant contributions from the end-point (soft) terms. The numerical values of the four form-factors $f_1(0)$, $f_2(0)$, $g_1(0)$ and $g_2(0)$ are compatible with the experimental data and theoretical calculations (in magnitude); although the uncertainties are large. |
hep-ph/9710415 | Goran Senjanovic | Borut Bajc, Antonio Riotto and Goran Senjanovic' | Large Lepton Number of the Universe and The Fate of Topological Defects | 4 pages, RevTex, some new numerical results and references. To be
published in Physical Review Letters | Phys.Rev.Lett. 81 (1998) 1355-1358 | 10.1103/PhysRevLett.81.1355 | DTP/97/92, IJS-TP-97/16, OUTP-97-49-P | hep-ph | null | We show that the monopole problem in Grand Unified Theories as well as the
domain wall problem may be easily solved if the lepton number asymmetry in the
Universe is large enough.
| [
{
"created": "Mon, 20 Oct 1997 18:54:00 GMT",
"version": "v1"
},
{
"created": "Mon, 27 Oct 1997 18:40:37 GMT",
"version": "v2"
},
{
"created": "Fri, 26 Jun 1998 17:39:33 GMT",
"version": "v3"
}
] | 2009-10-30 | [
[
"Bajc",
"Borut",
""
],
[
"Riotto",
"Antonio",
""
],
[
"Senjanovic'",
"Goran",
""
]
] | We show that the monopole problem in Grand Unified Theories as well as the domain wall problem may be easily solved if the lepton number asymmetry in the Universe is large enough. |
0910.2522 | Johan Alwall | Johan Alwall, Ayres Freitas, Olivier Mattelaer | Measuring Sparticles with the Matrix Element | 4 pages, 2 figures. To appear in the proceedings of SUSY09, the 17th
International Conference on Supersymmetry and the Unification of Fundamental
Interactions. Figures replaced (corrected y axis labels) | AIP Conf.Proc.1200:442-445,2010 | 10.1063/1.3327611 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We apply the Matrix Element Method (MEM) to mass determination of squark pair
production with direct decay to quarks and LSP at the LHC, showing that
simultaneous mass determination of squarks and LSP is possible. We furthermore
propose methods for inclusion of QCD radiation effects in the MEM.
| [
{
"created": "Wed, 14 Oct 2009 03:30:36 GMT",
"version": "v1"
},
{
"created": "Fri, 16 Oct 2009 15:29:16 GMT",
"version": "v2"
}
] | 2015-05-14 | [
[
"Alwall",
"Johan",
""
],
[
"Freitas",
"Ayres",
""
],
[
"Mattelaer",
"Olivier",
""
]
] | We apply the Matrix Element Method (MEM) to mass determination of squark pair production with direct decay to quarks and LSP at the LHC, showing that simultaneous mass determination of squarks and LSP is possible. We furthermore propose methods for inclusion of QCD radiation effects in the MEM. |
hep-ph/9904482 | Neil Russell | Neil Russell | CPT and Lorentz Symmetry in Hydrogen and Antihydrogen | Latex, 12 pages, 3 figures, presented at the Meeting on CPT and
Lorentz Symmetry, Indiana University, Bloomington, November 1998 | null | null | IUHET 401 | hep-ph | null | Possibilities for observing signals of CPT and Lorentz violation in the
spectroscopy of hydrogen and antihydrogen are considered. We show that
transitions between the c and d hyperfine sublevels in the 1S state can exhibit
theoretically detectable effects that would be unsuppressed by powers of the
fine-structure constant. This transition may therefore offer some advantages
over 1S-2S two-photon spectroscopy.
| [
{
"created": "Wed, 28 Apr 1999 19:09:54 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Russell",
"Neil",
""
]
] | Possibilities for observing signals of CPT and Lorentz violation in the spectroscopy of hydrogen and antihydrogen are considered. We show that transitions between the c and d hyperfine sublevels in the 1S state can exhibit theoretically detectable effects that would be unsuppressed by powers of the fine-structure constant. This transition may therefore offer some advantages over 1S-2S two-photon spectroscopy. |
1903.07188 | Xian-Qiao Yu | Ze-Rui Liang, Xian-Qiao Yu | The perturbative QCD predictions for the decay B^{0}_{s}\rightarrow
SS(a_{0}(980),f_{0}(980),f_{0}(500)) | 16pages, 6figures | Phys. Rev. D 102, 116007 (2020) | 10.1103/PhysRevD.102.116007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In this work, we calculate the branching ratios and CP violations of the
B^{0}_{s}\rightarrow a_{0}(980)a_{0}(980) decay modes with both charged and
neutral a_{0}(980) mesons and B^{0}_{s}\rightarrow
f_{0}(980)(f_{0}(500))f_{0}(980)(f_{0}(500)) for the first time in the pQCD
approach. Considering the recent observation of the BESIII collaboration that
provide a direct information about the constituent two-quark components in the
corresponding a_{0}(980) wave functions, we regard the scalar mesons
a_{0}(980), f_{0}(980) and f_{0}(500) as the q\bar{q} quark component in our
present work, and then make predictions of these decay modes. The branching
ratios of our calculations are at the order of the 10^{-4}\sim10^{-6} when we
consider the mixing scheme. We also calculate the CP violation parameters of
these decay modes. The relatively large branching ratios make it easily to be
tested by the running LHC-b experiments, and it can help us to understand both
the inner properties and the QCD behavior of the scalar meson.
| [
{
"created": "Sun, 17 Mar 2019 22:20:21 GMT",
"version": "v1"
},
{
"created": "Fri, 3 Apr 2020 05:45:40 GMT",
"version": "v2"
},
{
"created": "Sat, 25 Jul 2020 02:56:23 GMT",
"version": "v3"
},
{
"created": "Sat, 5 Dec 2020 04:02:19 GMT",
"version": "v4"
}
] | 2021-01-04 | [
[
"Liang",
"Ze-Rui",
""
],
[
"Yu",
"Xian-Qiao",
""
]
] | In this work, we calculate the branching ratios and CP violations of the B^{0}_{s}\rightarrow a_{0}(980)a_{0}(980) decay modes with both charged and neutral a_{0}(980) mesons and B^{0}_{s}\rightarrow f_{0}(980)(f_{0}(500))f_{0}(980)(f_{0}(500)) for the first time in the pQCD approach. Considering the recent observation of the BESIII collaboration that provide a direct information about the constituent two-quark components in the corresponding a_{0}(980) wave functions, we regard the scalar mesons a_{0}(980), f_{0}(980) and f_{0}(500) as the q\bar{q} quark component in our present work, and then make predictions of these decay modes. The branching ratios of our calculations are at the order of the 10^{-4}\sim10^{-6} when we consider the mixing scheme. We also calculate the CP violation parameters of these decay modes. The relatively large branching ratios make it easily to be tested by the running LHC-b experiments, and it can help us to understand both the inner properties and the QCD behavior of the scalar meson. |
1601.07508 | Enrico Bertuzzo Prof. | Enrico Bertuzzo, Pedro A.N. Machado and Marco Taoso | Di-Photon excess in the 2HDM: hasting towards the instability and the
non-perturbative regime | 11 pages, 2 figures | Phys. Rev. D 94, 115006 (2016) | 10.1103/PhysRevD.94.115006 | IFT-UAM/CSIC-16-008, FTUAM-16-3 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We challenge the interpretation of the di-photon excess recently observed by
both ATLAS and CMS in a two Higgs doublet framework. Due to the large
enhancement necessary to obtain the observed di-photon signal, a large number
of colored and charged vector-like fermions are called for. We find that even
before the hypercharge gauge coupling becomes non perturbative, the one loop
effects of these fermions abruptly drive the scalar potential to instability.
| [
{
"created": "Wed, 27 Jan 2016 19:16:05 GMT",
"version": "v1"
}
] | 2016-12-07 | [
[
"Bertuzzo",
"Enrico",
""
],
[
"Machado",
"Pedro A. N.",
""
],
[
"Taoso",
"Marco",
""
]
] | We challenge the interpretation of the di-photon excess recently observed by both ATLAS and CMS in a two Higgs doublet framework. Due to the large enhancement necessary to obtain the observed di-photon signal, a large number of colored and charged vector-like fermions are called for. We find that even before the hypercharge gauge coupling becomes non perturbative, the one loop effects of these fermions abruptly drive the scalar potential to instability. |
hep-ph/0308184 | Yurii V. Dumin | Yurii V. Dumin (IZMIRAN, Russ. Acad. Scis.) | Topological Defect Density in One-Dimensional Friedmann-Robertson-Walker
Cosmological Model: Corrections Inferred from the
Multi-Josephson-Junction-Loop Experiment | 4 pages, 3 eps figures, REVTeX 4. New version: abstract rewritten,
Introduction substantially extended, some textual changes in other parts of
the article, one figure excluded, a few references changed | null | null | null | hep-ph astro-ph cond-mat gr-qc | null | The data on a strongly-nonequilibrium superconducting phase transition in the
multi-Josephson-junction loop (MJJL), which represents a close analog of
one-dimensional Friedmann-Robertson-Walker cosmological model, are used to
refine a concentration of topological defects after the phase transitions of
Higgs fields in the early Universe. The thermal correlations between the phases
of order parameter revealed in MJJL can reduce considerably the expected number
of cosmological defects and, thereby, show a new way to resolve the
long-standing problem of their excessive concentration.
| [
{
"created": "Mon, 18 Aug 2003 23:51:08 GMT",
"version": "v1"
},
{
"created": "Tue, 28 Oct 2003 22:58:44 GMT",
"version": "v2"
},
{
"created": "Tue, 23 Dec 2003 01:34:06 GMT",
"version": "v3"
}
] | 2007-05-23 | [
[
"Dumin",
"Yurii V.",
"",
"IZMIRAN, Russ. Acad. Scis."
]
] | The data on a strongly-nonequilibrium superconducting phase transition in the multi-Josephson-junction loop (MJJL), which represents a close analog of one-dimensional Friedmann-Robertson-Walker cosmological model, are used to refine a concentration of topological defects after the phase transitions of Higgs fields in the early Universe. The thermal correlations between the phases of order parameter revealed in MJJL can reduce considerably the expected number of cosmological defects and, thereby, show a new way to resolve the long-standing problem of their excessive concentration. |
1403.4032 | Zhi Yang | Feng-Kun Guo, Ulf-G. Mei{\ss}ner, Wei Wang and Zhi Yang | Production of charm-strange hadronic molecules at the LHC | 20 pages, 4 figures, version accepted for publication in JHEP | JHEP 1405 (2014) 138 | 10.1007/JHEP05(2014)138 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We explore the inclusive hadroproduction of the D_{s0}^*(2317), D_{s1}(2460)
and D_{sJ}(2860) states at the Large Hadron Collider under the assumption that
these hadrons are S-wave meson-meson molecules. In addition, the D_{s2}(2910),
a predicted bound state of the D_2(2460)K system, is also discussed. We first
derive a factorisation formula for the production rates based on effective
field theory. Then we make use of two MC event generators, Herwig and Pythia,
to simulate the production of pairs of charmed mesons and kaons. Using
effective field theory to handle the final state interaction among the meson
pairs, we give an estimate of the inclusive production rates for these
particles at the order-of-magnitude accuracy. Our results show that the cross
sections for the pp --> D_{s0}^*(2317) and pp --> D_{s1}(2460) at the LHC are
at O(1 \mu b) level, while the ones for the pp --> D_{sJ}(2860) and the pp -->
D_{s2}(2910) are smaller by about one order of magnitude. Such estimates
suggest that these four exotic states could be copiously produced at the LHC. A
study of these states at the LHC will thus provide valuable information on
hadron spectroscopy as well as hadron interactions.
| [
{
"created": "Mon, 17 Mar 2014 09:15:42 GMT",
"version": "v1"
},
{
"created": "Wed, 30 Apr 2014 09:10:04 GMT",
"version": "v2"
}
] | 2014-06-12 | [
[
"Guo",
"Feng-Kun",
""
],
[
"Meißner",
"Ulf-G.",
""
],
[
"Wang",
"Wei",
""
],
[
"Yang",
"Zhi",
""
]
] | We explore the inclusive hadroproduction of the D_{s0}^*(2317), D_{s1}(2460) and D_{sJ}(2860) states at the Large Hadron Collider under the assumption that these hadrons are S-wave meson-meson molecules. In addition, the D_{s2}(2910), a predicted bound state of the D_2(2460)K system, is also discussed. We first derive a factorisation formula for the production rates based on effective field theory. Then we make use of two MC event generators, Herwig and Pythia, to simulate the production of pairs of charmed mesons and kaons. Using effective field theory to handle the final state interaction among the meson pairs, we give an estimate of the inclusive production rates for these particles at the order-of-magnitude accuracy. Our results show that the cross sections for the pp --> D_{s0}^*(2317) and pp --> D_{s1}(2460) at the LHC are at O(1 \mu b) level, while the ones for the pp --> D_{sJ}(2860) and the pp --> D_{s2}(2910) are smaller by about one order of magnitude. Such estimates suggest that these four exotic states could be copiously produced at the LHC. A study of these states at the LHC will thus provide valuable information on hadron spectroscopy as well as hadron interactions. |
2211.17183 | Antonio Rodr\'iguez S\'anchez | Johan Bijnens, Nils Hermansson-Truedsson, and Antonio
Rodr\'iguez-S\'anchez | Constraints on the hadronic light-by-light in the Melnikov-Vainshtein
regime | 35 pages, 4 figures. Published version | null | 10.1007/JHEP02(2023)167 | LU-TP 22-63 | hep-ph | http://creativecommons.org/licenses/by/4.0/ | The muon anomalous magnetic moment continues to attract attention due to the
possible tension between the experimentally measured value and the theoretical
Standard Model prediction. With the aim to reduce the uncertainty on the
hadronic light-by-light contribution to the magnetic moment, we derive
short-distance constraints in the Melnikov-Vainshtein regime which are useful
for data-driven determinations. In this kinematical region, two of the four
electromagnetic currents are close in the four-point function defining the
hadronic light-by-light tensor. To obtain the constraints, we develop a
systematic operator product expansion of the tensor in question to
next-to-leading order in the expansion in operators. We evaluate the leading in
$\alpha_s$ contributions and derive constraints for the next-to-leading
operators that are also valid nonperturbatively.
| [
{
"created": "Wed, 30 Nov 2022 17:27:21 GMT",
"version": "v1"
},
{
"created": "Fri, 17 Feb 2023 14:23:51 GMT",
"version": "v2"
}
] | 2023-03-22 | [
[
"Bijnens",
"Johan",
""
],
[
"Hermansson-Truedsson",
"Nils",
""
],
[
"Rodríguez-Sánchez",
"Antonio",
""
]
] | The muon anomalous magnetic moment continues to attract attention due to the possible tension between the experimentally measured value and the theoretical Standard Model prediction. With the aim to reduce the uncertainty on the hadronic light-by-light contribution to the magnetic moment, we derive short-distance constraints in the Melnikov-Vainshtein regime which are useful for data-driven determinations. In this kinematical region, two of the four electromagnetic currents are close in the four-point function defining the hadronic light-by-light tensor. To obtain the constraints, we develop a systematic operator product expansion of the tensor in question to next-to-leading order in the expansion in operators. We evaluate the leading in $\alpha_s$ contributions and derive constraints for the next-to-leading operators that are also valid nonperturbatively. |
hep-ph/0106111 | Dietrich Matthes | Dietrich Matthes | Debye Screening Mass from effective Potentials in Lattice Gauge Theory | 11 pages, 3 figures | null | null | null | hep-ph | null | In this paper, we use a definition of the Debye screening mass in SU(2) pure
gauge theory at high temperature in 3+1 dimensions, that makes use of the walls
between different $Z_2$ domains. We show, that this definition enables us to
unambiguously obtain the Debye Screening mass from the curvature of the
effective potential for the Polyakov loops calculated in the modified axial
gauge. Using an approach on asymmetric lattices, we obtain numerical values for
the Debye mass and compare them to perturbative as well as Monte-Carlo results.
Our resulting Debye-Masses are significantly higher than the one-loop
perturbative one. They are within the errors in agreement with those obtained
by Monte-Carlo methods. Open questions are discussed.
| [
{
"created": "Mon, 11 Jun 2001 12:14:34 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Matthes",
"Dietrich",
""
]
] | In this paper, we use a definition of the Debye screening mass in SU(2) pure gauge theory at high temperature in 3+1 dimensions, that makes use of the walls between different $Z_2$ domains. We show, that this definition enables us to unambiguously obtain the Debye Screening mass from the curvature of the effective potential for the Polyakov loops calculated in the modified axial gauge. Using an approach on asymmetric lattices, we obtain numerical values for the Debye mass and compare them to perturbative as well as Monte-Carlo results. Our resulting Debye-Masses are significantly higher than the one-loop perturbative one. They are within the errors in agreement with those obtained by Monte-Carlo methods. Open questions are discussed. |
1809.02624 | James Ingoldby | T. Appelquist, R. C. Brower, G. T. Fleming, A. Gasbarro, A.
Hasenfratz, J. Ingoldby, J. Kiskis, J. C. Osborn, C. Rebbi, E. Rinaldi, D.
Schaich, P. Vranas, E. Weinberg, O. Witzel (for the LSD Collaboration) | Linear Sigma EFT for Nearly Conformal Gauge Theories | 9 pages, 1 figure, published version | Phys. Rev. D 98, 114510 (2018) | 10.1103/PhysRevD.98.114510 | RBRC-1291 | hep-ph hep-lat | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a generalized linear sigma model as an effective field theory
(EFT) to describe nearly conformal gauge theories at low energies. The work is
motivated by recent lattice studies of gauge theories near the conformal
window, which have shown that the lightest flavor-singlet scalar state in the
spectrum ($\sigma$) can be much lighter than the vector state ($\rho$) and
nearly degenerate with the PNGBs ($\pi$) over a large range of quark masses.
The EFT incorporates this feature. We highlight the crucial role played by the
terms in the potential that explicitly break chiral symmetry. The explicit
breaking can be large enough so that a limited set of additional terms in the
potential can no longer be neglected, with the EFT still weakly coupled in this
new range. The additional terms contribute importantly to the scalar and pion
masses. In particular, they relax the inequality $M_{\sigma}^2 \ge 3
M_{\pi}^2$, allowing for consistency with current lattice data.
| [
{
"created": "Fri, 7 Sep 2018 18:08:54 GMT",
"version": "v1"
},
{
"created": "Thu, 10 Jan 2019 19:10:30 GMT",
"version": "v2"
}
] | 2019-01-14 | [
[
"Appelquist",
"T.",
"",
"for the LSD Collaboration"
],
[
"Brower",
"R. C.",
"",
"for the LSD Collaboration"
],
[
"Fleming",
"G. T.",
"",
"for the LSD Collaboration"
],
[
"Gasbarro",
"A.",
"",
"for the LSD Collaboration"
],
[
"Hase... | We construct a generalized linear sigma model as an effective field theory (EFT) to describe nearly conformal gauge theories at low energies. The work is motivated by recent lattice studies of gauge theories near the conformal window, which have shown that the lightest flavor-singlet scalar state in the spectrum ($\sigma$) can be much lighter than the vector state ($\rho$) and nearly degenerate with the PNGBs ($\pi$) over a large range of quark masses. The EFT incorporates this feature. We highlight the crucial role played by the terms in the potential that explicitly break chiral symmetry. The explicit breaking can be large enough so that a limited set of additional terms in the potential can no longer be neglected, with the EFT still weakly coupled in this new range. The additional terms contribute importantly to the scalar and pion masses. In particular, they relax the inequality $M_{\sigma}^2 \ge 3 M_{\pi}^2$, allowing for consistency with current lattice data. |
hep-ph/0701226 | Vitaly Okorokov A | V.A. Okorokov (1), S.B. Nurushev (2) ((1) MEPhI, Moscow, (2) IHEP,
Protvino) | Spin matrix elements for the elastic proton-proton and proton-antiproton
collisions | 6 pages, 2 pictures, XVIII International Baldin Seminar on High
Energy Physics Problems "Relativistic Nuclear Physics and Quantum
Chromodynamics", Baldin ISHEPP XVIII, September 25-30, 2006, Dubna, Russia | null | null | null | hep-ph | null | Motivated by the present extensive RHIC (BNL) spin program and further PAX
project at FAIR, we study the possibility of explicit reconstruction of full
set of helicity amplitudes by joint consideration of elastic proton-proton and
proton-antiproton scattering. Procedure is based on the derivative relations
for the helicity amplitudes, explicit parametrization of the leading spin
non-flip amplitudes and crossing - symmetry relations. Some preliminary results
are presented for the PAX energies to show the expected magnitudes of the spin
dependent observables as a functions of invariant Mandelstam's variables $s$
and $t$.
| [
{
"created": "Fri, 26 Jan 2007 16:09:26 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Okorokov",
"V. A.",
""
],
[
"Nurushev",
"S. B.",
""
]
] | Motivated by the present extensive RHIC (BNL) spin program and further PAX project at FAIR, we study the possibility of explicit reconstruction of full set of helicity amplitudes by joint consideration of elastic proton-proton and proton-antiproton scattering. Procedure is based on the derivative relations for the helicity amplitudes, explicit parametrization of the leading spin non-flip amplitudes and crossing - symmetry relations. Some preliminary results are presented for the PAX energies to show the expected magnitudes of the spin dependent observables as a functions of invariant Mandelstam's variables $s$ and $t$. |
1912.05733 | James Dent | James B. Dent, Bhaskar Dutta, Doojin Kim, Shu Liao, Rupak Mahapatra,
Kuver Sinha, and Adrian Thompson | New Directions for Axion Searches via Scattering at Reactor Neutrino
Experiments | 6 pages, 3 figures, Accepted for publication in Physical Review
Letters. Figures have been updated since version 1 | null | 10.1103/PhysRevLett.124.211804 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Searches for pseudoscalar axion-like-particles (ALPs) typically rely on their
decay in beam dumps or their conversion into photons in haloscopes and
helioscopes. We point out a new experimental direction for ALP probes through
their production via the Primakoff process or Compton-like scattering off of
electrons or nuclei. We consider ALPs produced by the intense gamma ray flux
available from megawatt-scale nuclear reactors at neutrino experiments through
Primakoff-like or Compton-like channels. Low-threshold detectors in close
proximity to the core will have visibility to ALP decays and inverse Primakoff
and Compton scattering, providing sensitivity to the ALP-photon and
ALP-electron couplings. We find that the sensitivity to these couplings at the
ongoing MINER neutrino experiment exceeds existing limits set by laboratory
experiments and, for the ALP-electron coupling, we forecast the world's best
laboratory-based constraints over a large portion of the sub-MeV ALP mass
range.
| [
{
"created": "Thu, 12 Dec 2019 02:11:24 GMT",
"version": "v1"
},
{
"created": "Thu, 21 May 2020 23:03:11 GMT",
"version": "v2"
}
] | 2020-06-24 | [
[
"Dent",
"James B.",
""
],
[
"Dutta",
"Bhaskar",
""
],
[
"Kim",
"Doojin",
""
],
[
"Liao",
"Shu",
""
],
[
"Mahapatra",
"Rupak",
""
],
[
"Sinha",
"Kuver",
""
],
[
"Thompson",
"Adrian",
""
]
] | Searches for pseudoscalar axion-like-particles (ALPs) typically rely on their decay in beam dumps or their conversion into photons in haloscopes and helioscopes. We point out a new experimental direction for ALP probes through their production via the Primakoff process or Compton-like scattering off of electrons or nuclei. We consider ALPs produced by the intense gamma ray flux available from megawatt-scale nuclear reactors at neutrino experiments through Primakoff-like or Compton-like channels. Low-threshold detectors in close proximity to the core will have visibility to ALP decays and inverse Primakoff and Compton scattering, providing sensitivity to the ALP-photon and ALP-electron couplings. We find that the sensitivity to these couplings at the ongoing MINER neutrino experiment exceeds existing limits set by laboratory experiments and, for the ALP-electron coupling, we forecast the world's best laboratory-based constraints over a large portion of the sub-MeV ALP mass range. |
hep-ph/0107325 | Pran Nath | Tarek Ibrahim and Pran Nath | Large Phases and CP Violation in SUSY | Revised version with typos corrected. 8 pages,sprocl, and no figures.
Invited plenary talk at the 9th International Conference on Supersymmetry and
Unification of Fundamental Interactions at Dubna, Russia, June 11-17, 2001 | null | 10.1142/9789812778192_0022 | null | hep-ph | null | A brief overview is given of recent developments in the analyses of large
phases and CP violation in supersymmetric unified models. The problem of
experimental electric dipole moment constraints and large phases is discussed.
Implications of large phases on supersymmetric phenomena are reviewed. The
possibility of generating a muon electric dipole moment much larger than
implied by the scaling relation $d_{\mu}/d_e\simeq m_{\mu}/m_e$ from lepton
flavor nonuniversality and within reach of the recently proposed Brookhaven
experiment for a sensitive probe of $d_{\mu}$ is also discussed.
| [
{
"created": "Tue, 31 Jul 2001 15:44:56 GMT",
"version": "v1"
},
{
"created": "Thu, 2 Aug 2001 15:30:30 GMT",
"version": "v2"
}
] | 2017-08-23 | [
[
"Ibrahim",
"Tarek",
""
],
[
"Nath",
"Pran",
""
]
] | A brief overview is given of recent developments in the analyses of large phases and CP violation in supersymmetric unified models. The problem of experimental electric dipole moment constraints and large phases is discussed. Implications of large phases on supersymmetric phenomena are reviewed. The possibility of generating a muon electric dipole moment much larger than implied by the scaling relation $d_{\mu}/d_e\simeq m_{\mu}/m_e$ from lepton flavor nonuniversality and within reach of the recently proposed Brookhaven experiment for a sensitive probe of $d_{\mu}$ is also discussed. |
1012.0261 | Arie Bodek | Arie Bodek and Un-Ki Yang | Update to the Bodek-Yang Unified Model for Electron- and Neutrino-
Nucleon Scattering Cross Sections | Presented at 35th International Conference of High Energy Physics -
ICHEP2010, July 22-28, 2010, Paris France. Four pages | PoS ICHEP2010:292,2010 | null | null | hep-ph hep-ex nucl-ex nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We construct a model for inelastic neutrino- and electron-nucleon scattering
cross sections using effective leading order parton distribution functions with
a new scaling variable $\xi_w$. Non-perturbative effects are well described
using the $\xi_w$ scaling variable, in combination with multiplicative $K$
factors at low $Q^2$. Our model describes all inelastic charged lepton-nucleon
scattering (including resonance) data (HERA/NMC/BCDMS/SLAC/JLab) ranging from
very high $Q^2$ to very low $Q^2$ and down to the photo-production region. The
model describes existing inelastic neutrino-nucleon scattering measurements,
and is currently used in analyses of neutrino oscillation experiments in the
few GeV region.
| [
{
"created": "Wed, 1 Dec 2010 18:06:29 GMT",
"version": "v1"
}
] | 2016-04-26 | [
[
"Bodek",
"Arie",
""
],
[
"Yang",
"Un-Ki",
""
]
] | We construct a model for inelastic neutrino- and electron-nucleon scattering cross sections using effective leading order parton distribution functions with a new scaling variable $\xi_w$. Non-perturbative effects are well described using the $\xi_w$ scaling variable, in combination with multiplicative $K$ factors at low $Q^2$. Our model describes all inelastic charged lepton-nucleon scattering (including resonance) data (HERA/NMC/BCDMS/SLAC/JLab) ranging from very high $Q^2$ to very low $Q^2$ and down to the photo-production region. The model describes existing inelastic neutrino-nucleon scattering measurements, and is currently used in analyses of neutrino oscillation experiments in the few GeV region. |
hep-ph/9811419 | Concha Gonzalez Garcia | M.C. Gonzalez-Garcia | Neutrinos Mass and Mixing | 10 Pages latex file, 6 postscript figures. To Appear in Proceedings
of Fifth International Workshop on Tau Lepton Physics, September 1998,
Santander, Spain | Nucl.Phys.Proc.Suppl.76:451-460,1999 | 10.1016/S0920-5632(99)00507-1 | null | hep-ph | null | I review the status of neutrino masses and mixings in the light of the solar
and atmospheric neutrino data. The result from the LSND experiment and the
possible role of neutrinos as hot dark matter are also included. I also discuss
the simplest schemes proposed to reconcile these data which include a light
sterile neutrino in addition to the three standard ones. Implications for
future experiments are commented.
| [
{
"created": "Fri, 20 Nov 1998 12:05:10 GMT",
"version": "v1"
}
] | 2011-02-07 | [
[
"Gonzalez-Garcia",
"M. C.",
""
]
] | I review the status of neutrino masses and mixings in the light of the solar and atmospheric neutrino data. The result from the LSND experiment and the possible role of neutrinos as hot dark matter are also included. I also discuss the simplest schemes proposed to reconcile these data which include a light sterile neutrino in addition to the three standard ones. Implications for future experiments are commented. |
hep-ph/0502040 | Bogdan Mihaila | Fred Cooper, John F. Dawson, and Bogdan Mihaila | Renormalized broken-symmetry Schwinger-Dyson equations and the 2PI-1/N
expansion for the O(N) model | null | Phys.Rev.D71:096003,2005 | 10.1103/PhysRevD.71.096003 | LA-UR 05-0556 | hep-ph | null | We derive the renormalized Schwinger-Dyson equations for the one- and
two-point functions in the auxiliary field formulation of $\lambda \phi^4$
field theory to order 1/N in the 2PI-1/N expansion. We show that the
renormalization of the broken-symmetry theory depends only on the counter terms
of the symmetric theory with $\phi = 0$. We find that the 2PI-1/N expansion
violates the Goldstone theorem at order 1/N. In using the O(4) model as a low
energy effective field theory of pions to study the time evolution of
disoriented chiral condensates one has to {\em{explicitly}} break the O(4)
symmetry to give the physical pions a nonzero mass. In this effective theory
the {\em additional} small contribution to the pion mass due to the violation
of the Goldstone theorem in the 2-PI-1/N equations should be numerically
unimportant.
| [
{
"created": "Thu, 3 Feb 2005 17:19:15 GMT",
"version": "v1"
},
{
"created": "Mon, 25 Apr 2005 00:30:21 GMT",
"version": "v2"
}
] | 2011-08-17 | [
[
"Cooper",
"Fred",
""
],
[
"Dawson",
"John F.",
""
],
[
"Mihaila",
"Bogdan",
""
]
] | We derive the renormalized Schwinger-Dyson equations for the one- and two-point functions in the auxiliary field formulation of $\lambda \phi^4$ field theory to order 1/N in the 2PI-1/N expansion. We show that the renormalization of the broken-symmetry theory depends only on the counter terms of the symmetric theory with $\phi = 0$. We find that the 2PI-1/N expansion violates the Goldstone theorem at order 1/N. In using the O(4) model as a low energy effective field theory of pions to study the time evolution of disoriented chiral condensates one has to {\em{explicitly}} break the O(4) symmetry to give the physical pions a nonzero mass. In this effective theory the {\em additional} small contribution to the pion mass due to the violation of the Goldstone theorem in the 2-PI-1/N equations should be numerically unimportant. |
hep-ph/0411084 | Ulrich Jentschura | K. Pachucki, U. D. Jentschura, V. A. Yerokhin | Nonrelativistic QED approach to the bound-electron g factor | 4 pages, RevTeX | Phys.Rev.Lett. 93 (2004) 150401; Erratum-ibid. 94 (2005) 229902 | 10.1103/PhysRevLett.93.150401 | null | hep-ph | null | Within a systematic approach based on nonrelativistic quantum electrodynamics
(NRQED), we derive the one-loop self-energy correction of order alpha
(Zalpha)^4 to the bound-electron g factor. In combination with numerical data,
this analytic result improves theoretical predictions for the self-energy
correction for carbon and oxygen by an order of magnitude. Basing on one-loop
calculations, we obtain the logarithmic two-loop contribution of order alpha^2
(Zalpha)^4 ln[(Zalpha)^-2] and the dominant part of the corresponding constant
term. The results obtained improve the accuracy of the theoretical predictions
for the 1S bound-electron g factor and influence the value of the electron mass
determined from g factor measurements.
| [
{
"created": "Fri, 5 Nov 2004 12:08:17 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Pachucki",
"K.",
""
],
[
"Jentschura",
"U. D.",
""
],
[
"Yerokhin",
"V. A.",
""
]
] | Within a systematic approach based on nonrelativistic quantum electrodynamics (NRQED), we derive the one-loop self-energy correction of order alpha (Zalpha)^4 to the bound-electron g factor. In combination with numerical data, this analytic result improves theoretical predictions for the self-energy correction for carbon and oxygen by an order of magnitude. Basing on one-loop calculations, we obtain the logarithmic two-loop contribution of order alpha^2 (Zalpha)^4 ln[(Zalpha)^-2] and the dominant part of the corresponding constant term. The results obtained improve the accuracy of the theoretical predictions for the 1S bound-electron g factor and influence the value of the electron mass determined from g factor measurements. |
1107.2856 | Matthew Dolan | B. C. Allanach, Matthew J. Dolan | Supersymmetry With Prejudice: Fitting the Wrong Model to LHC Data | 24 pages, 6 figures, v4: new discussion, clarification, 1 plot added | null | 10.1103/PhysRevD.86.055022 | IPPP/11/38; DCPT/11/76 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We critically examine interpretations of hypothetical supersymmetric LHC
signals, fitting to alternative wrong models of supersymmetry breaking. The
signals we consider are some of the most constraining on the sparticle
spectrum: invariant mass distributions with edges and end-points from the
golden cascade decay chain \tilde{q}_L -> q \chi_2^0 (-> \tilde{l}^{\pm}
l^{\mp} q) -> \chi_1^0 l^+ l^- q. We assume a CMSSM point to be the `correct'
one, and fit the signals instead to minimal gauge mediated supersymmetry
breaking models (mGMSB) with a neutralino quasi-stable lightest supersymmetric
particle, minimal anomaly mediation (mAMSB) and large volume string
compactification models (LVS). mAMSB and LVS can be unambiguously discriminated
against the CMSSM for the parameter point assumed and 1 inverse femtobarn of
LHC data at 14 TeV. However, mGMSB would not be discriminated on the basis of
the kinematic end-points alone, and would require further, more detailed
investigation. The best-fit points of mGMSB and CMSSM look remarkably similar,
making experimental discrimination at the LHC appear unlikely by any means.
| [
{
"created": "Thu, 14 Jul 2011 15:41:06 GMT",
"version": "v1"
},
{
"created": "Wed, 20 Jul 2011 14:02:26 GMT",
"version": "v2"
},
{
"created": "Mon, 12 Sep 2011 11:21:42 GMT",
"version": "v3"
},
{
"created": "Tue, 25 Oct 2011 15:17:30 GMT",
"version": "v4"
}
] | 2013-05-30 | [
[
"Allanach",
"B. C.",
""
],
[
"Dolan",
"Matthew J.",
""
]
] | We critically examine interpretations of hypothetical supersymmetric LHC signals, fitting to alternative wrong models of supersymmetry breaking. The signals we consider are some of the most constraining on the sparticle spectrum: invariant mass distributions with edges and end-points from the golden cascade decay chain \tilde{q}_L -> q \chi_2^0 (-> \tilde{l}^{\pm} l^{\mp} q) -> \chi_1^0 l^+ l^- q. We assume a CMSSM point to be the `correct' one, and fit the signals instead to minimal gauge mediated supersymmetry breaking models (mGMSB) with a neutralino quasi-stable lightest supersymmetric particle, minimal anomaly mediation (mAMSB) and large volume string compactification models (LVS). mAMSB and LVS can be unambiguously discriminated against the CMSSM for the parameter point assumed and 1 inverse femtobarn of LHC data at 14 TeV. However, mGMSB would not be discriminated on the basis of the kinematic end-points alone, and would require further, more detailed investigation. The best-fit points of mGMSB and CMSSM look remarkably similar, making experimental discrimination at the LHC appear unlikely by any means. |
1010.2838 | Pablo Roig | Zhi-Hui Guo, Pablo Roig | $\tau^-\to\pi^-\gamma\nu_\tau$ as a source of background on the Lepton
Flavour Violating decay $\tau^-\to\mu^-\gamma$ | 6 pages, 7 figures. Contribution to the Proceedings of the TAU10
Conference held in Manchester, 13-17 September 2010. To be published in Nucl.
Phys. Proc. Suppl | Nucl.Phys.Proc.Suppl.218:122-127,2011 | 10.1016/j.nuclphysbps.2011.06.021 | LPT-ORSAY-10-69 | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We calculate the decay of $\tau^-\to\pi^-\gamma\nu_\tau$ in the framework of
Resonance Chiral Theory ($R\chi T$). By demanding the high energy constraints
from QCD on the related form factors, we could predict the various physical
observables of $\tau^-\to\pi^-\gamma\nu_\tau$ without any free parameter. Our
results show that for a realistic cut on the photon energy (around $100$ MeV)
this mode gives a branching ratio of roughly $0.1%$ that should have already
been detected at the heavy-flavour factories. Another interesting subject we
have studied based on our calculation of the decay
$\tau^-\to\pi^-\gamma\nu_\tau$ is the experimental background estimation of the
lepton flavour violation process $\tau^- \to \mu^- \gamma$. We point out that
although the description of radiation that PHOTOS provides -which has been used
by BaBar and Belle collaborations to estimate this source of background- is in
excellent agreement with the theoretical expectations in the low energy region
in $\tau^-\to\pi^-\gamma\nu_\tau$ decay, this is not the case in the high
energy region, precisely where it is easier that this decay mimics the process
$\tau^-\to\mu^-\gamma$.
| [
{
"created": "Thu, 14 Oct 2010 07:10:54 GMT",
"version": "v1"
}
] | 2011-09-20 | [
[
"Guo",
"Zhi-Hui",
""
],
[
"Roig",
"Pablo",
""
]
] | We calculate the decay of $\tau^-\to\pi^-\gamma\nu_\tau$ in the framework of Resonance Chiral Theory ($R\chi T$). By demanding the high energy constraints from QCD on the related form factors, we could predict the various physical observables of $\tau^-\to\pi^-\gamma\nu_\tau$ without any free parameter. Our results show that for a realistic cut on the photon energy (around $100$ MeV) this mode gives a branching ratio of roughly $0.1%$ that should have already been detected at the heavy-flavour factories. Another interesting subject we have studied based on our calculation of the decay $\tau^-\to\pi^-\gamma\nu_\tau$ is the experimental background estimation of the lepton flavour violation process $\tau^- \to \mu^- \gamma$. We point out that although the description of radiation that PHOTOS provides -which has been used by BaBar and Belle collaborations to estimate this source of background- is in excellent agreement with the theoretical expectations in the low energy region in $\tau^-\to\pi^-\gamma\nu_\tau$ decay, this is not the case in the high energy region, precisely where it is easier that this decay mimics the process $\tau^-\to\mu^-\gamma$. |
0911.4964 | Kirill Tuchin | Kirill Tuchin | Nonlinear pair production in scattering of photons on ultra-short laser
pulses at high energy | 16 pages, 7 figures; v2: presentation improved, references added,
typos fixed | Phys.Lett.B686:29-35,2010 | 10.1016/j.physletb.2010.02.026 | RBRC-814 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We consider scattering of a photon on a short intense laser pulse at high
energy. We argue that for ultra-short laser pulses the interaction is coherent
over the entire length of the pulse. At low pulse intensity $I$ the total cross
section for electron-positron pair production is proportional to $I$. However,
at pulse intensities higher than the characteristic value $I_s$, the total
cross section saturates -- it becomes proportional to the logarithm of
intensity. This nonlinear effect is due to multi-photon interactions. We derive
the total cross section for pair production at high energies by resuming the
multi-photon amplitudes to all orders in intensity. We calculate the saturation
intensity $I_s$ and show that it is significantly lower than the Schwinger's
critical value. We discuss possible experimental tests.
| [
{
"created": "Wed, 25 Nov 2009 21:48:49 GMT",
"version": "v1"
},
{
"created": "Mon, 15 Feb 2010 20:42:47 GMT",
"version": "v2"
}
] | 2014-11-20 | [
[
"Tuchin",
"Kirill",
""
]
] | We consider scattering of a photon on a short intense laser pulse at high energy. We argue that for ultra-short laser pulses the interaction is coherent over the entire length of the pulse. At low pulse intensity $I$ the total cross section for electron-positron pair production is proportional to $I$. However, at pulse intensities higher than the characteristic value $I_s$, the total cross section saturates -- it becomes proportional to the logarithm of intensity. This nonlinear effect is due to multi-photon interactions. We derive the total cross section for pair production at high energies by resuming the multi-photon amplitudes to all orders in intensity. We calculate the saturation intensity $I_s$ and show that it is significantly lower than the Schwinger's critical value. We discuss possible experimental tests. |
2107.10512 | Henning Bahl | Henning Bahl | Measuring single-top-associated Higgs production at the HL-LHC | Contribution to the proceedings of DIS 2021, XXVIII International
Workshop on Deep-Inelastic Scattering and Related Subjects. arXiv admin note:
substantial text overlap with arXiv:2105.06674 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Precision measurements of top-associated Higgs production are an important
ingredient to unravel the $\mathcal{CP}$ nature of the Higgs boson. In this
work, we constraint the $\mathcal{CP}$ nature of the top-Yukawa coupling taking
into account all relevant inclusive and differential Higgs boson measurements.
Based upon this fit, we show that it is crucial to disentangle single- and
di-top-associated Higgs production for tightening indirect constraints on a
$\mathcal{CP}$-odd top-Yukawa coupling in the future. In this context, we
propose an analysis strategy for measuring $tH$ production at the HL-LHC
without relying on assumptions about the Higgs $\mathcal{CP}$ character.
| [
{
"created": "Thu, 22 Jul 2021 08:16:24 GMT",
"version": "v1"
}
] | 2021-07-23 | [
[
"Bahl",
"Henning",
""
]
] | Precision measurements of top-associated Higgs production are an important ingredient to unravel the $\mathcal{CP}$ nature of the Higgs boson. In this work, we constraint the $\mathcal{CP}$ nature of the top-Yukawa coupling taking into account all relevant inclusive and differential Higgs boson measurements. Based upon this fit, we show that it is crucial to disentangle single- and di-top-associated Higgs production for tightening indirect constraints on a $\mathcal{CP}$-odd top-Yukawa coupling in the future. In this context, we propose an analysis strategy for measuring $tH$ production at the HL-LHC without relying on assumptions about the Higgs $\mathcal{CP}$ character. |
1611.09673 | George W. S. Hou | George W.S. Hou | Loophole in $K \to \pi \nu \bar\nu$ Search \ \& $K_L \to \pi^0 \nu
\bar\nu$ Beyond Grossman--Nir Bound | 6 pages, 3 figures, talk presented at KAON2016, to appear in
proceedings | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The Grossman-Nir bound concept is robust, but the common perception of $K_L
\to \pi^0\nu\bar\nu < 1.4 \times 10^{-9}$ may be circumvented. Because of the
blinding $K\pi2$(3) decay, $K^+$ decay experiments such as E787/E949 and the
currently running NA62 kinematically exclude the "blinding zone". This offers
an opportunity for the currently running KOTO experiment. With no kinematic
control, if the KOTO experiment is able to veto all true background, it may
discover $K_L \to \pi^0 + X^0$, where $X^0$ is an invisible "dark" boson with
mass $m_{X^0} \sim m_{\pi^0}$. This could happen with 2015 data at hand, which
supposedly should allow KOTO to reach nominal GN bound sensitivity. An explicit
model of gauged $L_\mu - L_\tau$, linked with muon $g-2$ hence with very light
$Z'$, is given. Adding vector-like quarks that mix with usual quarks, $W$-boson
loops induce $s\to dZ'$ and $b\to sZ'$ transitions. Besides realizing the
scenario, the model provides further illustration of potential impact. Given
that usual dark bosons linked with the photon are tightly constrained, KOTO has
a unique opportunity to probe the muon-related dark sector.
| [
{
"created": "Tue, 29 Nov 2016 15:13:58 GMT",
"version": "v1"
}
] | 2016-11-30 | [
[
"Hou",
"George W. S.",
""
]
] | The Grossman-Nir bound concept is robust, but the common perception of $K_L \to \pi^0\nu\bar\nu < 1.4 \times 10^{-9}$ may be circumvented. Because of the blinding $K\pi2$(3) decay, $K^+$ decay experiments such as E787/E949 and the currently running NA62 kinematically exclude the "blinding zone". This offers an opportunity for the currently running KOTO experiment. With no kinematic control, if the KOTO experiment is able to veto all true background, it may discover $K_L \to \pi^0 + X^0$, where $X^0$ is an invisible "dark" boson with mass $m_{X^0} \sim m_{\pi^0}$. This could happen with 2015 data at hand, which supposedly should allow KOTO to reach nominal GN bound sensitivity. An explicit model of gauged $L_\mu - L_\tau$, linked with muon $g-2$ hence with very light $Z'$, is given. Adding vector-like quarks that mix with usual quarks, $W$-boson loops induce $s\to dZ'$ and $b\to sZ'$ transitions. Besides realizing the scenario, the model provides further illustration of potential impact. Given that usual dark bosons linked with the photon are tightly constrained, KOTO has a unique opportunity to probe the muon-related dark sector. |
1209.4291 | Aleksander Kusina | S. Jadach, M. Jezabek, A. Kusina, W. Placzek, M. Skrzypek | NLO corrections to hard process in QCD shower -- proof of concept | Acta Physica Polonica in press | Acta Phys. Polon. B43, 2067 (2012) | 10.5506/APhysPolB.43.2067 | IFJPAN-IV-2012-6; SMU-HEP-12-14 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The concept of new methodology of adding QCD NLO corrections in the initial
state Monte Carlo parton shower (hard process part) is tested numerically
using, as an example, the process of the heavy boson production at
hadron--hadron colliders such as LHC. In spite of the use of a simplified model
of the process, all presented numerical results prove convincingly that the
basic concept of the new methodology works correctly in practice, that is in
the numerical environment of the Monte Carlo parton shower event generator. The
differences with the other well established methods, like MC@NLO and POWHEG,
are briefly discussed and future refinements of the implementation of the new
method are also outlined.
| [
{
"created": "Wed, 19 Sep 2012 16:08:38 GMT",
"version": "v1"
},
{
"created": "Thu, 15 Nov 2012 17:35:20 GMT",
"version": "v2"
}
] | 2013-01-03 | [
[
"Jadach",
"S.",
""
],
[
"Jezabek",
"M.",
""
],
[
"Kusina",
"A.",
""
],
[
"Placzek",
"W.",
""
],
[
"Skrzypek",
"M.",
""
]
] | The concept of new methodology of adding QCD NLO corrections in the initial state Monte Carlo parton shower (hard process part) is tested numerically using, as an example, the process of the heavy boson production at hadron--hadron colliders such as LHC. In spite of the use of a simplified model of the process, all presented numerical results prove convincingly that the basic concept of the new methodology works correctly in practice, that is in the numerical environment of the Monte Carlo parton shower event generator. The differences with the other well established methods, like MC@NLO and POWHEG, are briefly discussed and future refinements of the implementation of the new method are also outlined. |
hep-ph/0005135 | Osamu Yasuda | Osamu Yasuda | Neutrino oscillations in high energy cosmic neutrino flux | 4 pages, 4 figures, uses epsfig. Talk presented at Workshop on
Neutrino Oscillations and Their Origin, Fujiyoshida, Japan, February 11-13,
2000, to appear in Proceedings published by Universal Academy Press, Tokyo | null | null | TMUP-HEL-0009 | hep-ph | null | I discuss the effects of neutrino oscillations on high energy cosmic
neutrinos which come from cosmologically distant astrophysical sources. I
incorporate all the up-to-date constraints from the solar, atmospheric,
reactor, accelerator data and give the possible pattern for the ratio of the
high energy cosmic neutrinos in the cases of three and four neutrino schemes.
| [
{
"created": "Mon, 15 May 2000 05:23:04 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Yasuda",
"Osamu",
""
]
] | I discuss the effects of neutrino oscillations on high energy cosmic neutrinos which come from cosmologically distant astrophysical sources. I incorporate all the up-to-date constraints from the solar, atmospheric, reactor, accelerator data and give the possible pattern for the ratio of the high energy cosmic neutrinos in the cases of three and four neutrino schemes. |
0807.1404 | Dmitry Shirkov V. | Dmitry Shirkov | Large regular QCD coupling at Low Energy? | 12 pages, 5 figures, to be published in ``Quantum Field Theory and
Beyond'' (Essays in honor of Wolfhart Zimmermann on the occasion of his 80th
birthday), WS(Singapore) | null | 10.1142/9789812833556_0003 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The issue is the expediency of the QCD notions use in the low energy region
down to the confinement scale, and, in particular, the efficacy of the QCD
invariant coupling \bar{\alpha}_s(Q^2) with a minimal analytic modification in
this domain. To this goal, we overview a quite recent progress in application
of the ghost-free Analytic Perturbative Theory approach (with no adjustable
parameters) for QCD in the region below 1 GeV. Among them the Bethe--Salpeter
analysis of the meson spectra and spin-dependent (polarization) Bjorken sum
rule. The impression is that there is a chance for the theoretically consistent
and numerically correlated description of hadronic events from Z_0 till a few
hundred MeV scale by combination of analytic pQCD and some explicit
non-perturbative contribution in the spirit of duality. This is an invitation
to the practitioner community for a more courageous use of ghost-free QCD
coupling models for data analysis in the low energy region.
| [
{
"created": "Wed, 9 Jul 2008 09:24:14 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Shirkov",
"Dmitry",
""
]
] | The issue is the expediency of the QCD notions use in the low energy region down to the confinement scale, and, in particular, the efficacy of the QCD invariant coupling \bar{\alpha}_s(Q^2) with a minimal analytic modification in this domain. To this goal, we overview a quite recent progress in application of the ghost-free Analytic Perturbative Theory approach (with no adjustable parameters) for QCD in the region below 1 GeV. Among them the Bethe--Salpeter analysis of the meson spectra and spin-dependent (polarization) Bjorken sum rule. The impression is that there is a chance for the theoretically consistent and numerically correlated description of hadronic events from Z_0 till a few hundred MeV scale by combination of analytic pQCD and some explicit non-perturbative contribution in the spirit of duality. This is an invitation to the practitioner community for a more courageous use of ghost-free QCD coupling models for data analysis in the low energy region. |
1307.1131 | Stefano Carrazza | Stefano Carrazza | Towards the determination of the photon parton distribution function
constrained by LHC data | 5 pages, 10 figures, to appear in the proceedings of the XXI
International Workshop on Deep-Inelastic Scattering and Related Subjects
(DIS2013), Marseille, 22-26 April 2013 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We provide a discussion of the impact of a subset of Drell-Yan data from LHC
on the determination of the photon parton distribution function (PDF), using
the NNPDF methodology. In previous work we have shown that the photon PDF
determined from deep-inelastic scattering (DIS) data only has large
uncertainties, suggesting the need for more data from other processes such as
Drell-Yan, which unlike DIS, includes photon-induced contributions at leading
order in QED. We describe the inclusion of ATLAS Drell-Yan W, Z data, which is
a subset of the LHC data used in a final photon PDF determination, by means of
a reweighting procedure. We show the impact of such data by comparing the
reweighted photon PDF with the photon PDF from DIS, highlighting the reduction
of uncertainties at medium/small-x. We conclude that the Drell-Yan data from
LHC allows a reasonably accurate determination of the photon PDF.
| [
{
"created": "Wed, 3 Jul 2013 20:00:01 GMT",
"version": "v1"
}
] | 2013-07-05 | [
[
"Carrazza",
"Stefano",
""
]
] | We provide a discussion of the impact of a subset of Drell-Yan data from LHC on the determination of the photon parton distribution function (PDF), using the NNPDF methodology. In previous work we have shown that the photon PDF determined from deep-inelastic scattering (DIS) data only has large uncertainties, suggesting the need for more data from other processes such as Drell-Yan, which unlike DIS, includes photon-induced contributions at leading order in QED. We describe the inclusion of ATLAS Drell-Yan W, Z data, which is a subset of the LHC data used in a final photon PDF determination, by means of a reweighting procedure. We show the impact of such data by comparing the reweighted photon PDF with the photon PDF from DIS, highlighting the reduction of uncertainties at medium/small-x. We conclude that the Drell-Yan data from LHC allows a reasonably accurate determination of the photon PDF. |
2404.15186 | Steven Martinez | Richard F. Lebed and Steven R. Martinez | Diabatic Dynamical Diquark Bound States: Mass Corrections and Widths | 8 pages, 1 figure, 4 tables | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Using the diabatic formalism, which generalizes the adiabatic approximation
in the Born-Oppenheimer formalism, we apply well-known Hamiltonian methods to
calculate the effect of open di-meson thresholds that lie well below the mass
of elementary $c\bar c q\bar q^\prime$, $c\bar c s\bar s$, and $c \bar c q \bar
s$ tetraquark bound states. We compute the resulting mass shifts for these
states, as well as their decay widths to the corresponding meson pairs. Each
mass eigenstate, originally produced using a bound-state approximation under
the diabatic formalism, consists of an admixture of a compact
diquark-antidiquark configuration (an eigenstate of the original dynamical
diquark model) with an extended di-meson configuration induced by the nearest
threshold. We compare our results with those from our recent work that employs
a scattering formalism, and find a great deal of agreement, but also comment
upon interesting discrepancies between the two approaches.
| [
{
"created": "Tue, 23 Apr 2024 16:27:44 GMT",
"version": "v1"
}
] | 2024-04-24 | [
[
"Lebed",
"Richard F.",
""
],
[
"Martinez",
"Steven R.",
""
]
] | Using the diabatic formalism, which generalizes the adiabatic approximation in the Born-Oppenheimer formalism, we apply well-known Hamiltonian methods to calculate the effect of open di-meson thresholds that lie well below the mass of elementary $c\bar c q\bar q^\prime$, $c\bar c s\bar s$, and $c \bar c q \bar s$ tetraquark bound states. We compute the resulting mass shifts for these states, as well as their decay widths to the corresponding meson pairs. Each mass eigenstate, originally produced using a bound-state approximation under the diabatic formalism, consists of an admixture of a compact diquark-antidiquark configuration (an eigenstate of the original dynamical diquark model) with an extended di-meson configuration induced by the nearest threshold. We compare our results with those from our recent work that employs a scattering formalism, and find a great deal of agreement, but also comment upon interesting discrepancies between the two approaches. |
hep-ph/0004070 | Demir Durmus Ali | M. Boz (Hacettepe), D. A. Demir (ICTP), N. K. Pak (METU) | Q-ball formation in the MSSM with explicit CP violation | 6 pp | Mod.Phys.Lett. A15 (2000) 517 | 10.1142/S0217732300000505 | IC/00/45 | hep-ph | null | Q-balls generically exist in the supersymmetric extensions of the standard
model. Taking into account the additional sources of CP violation, which are
naturally accomodated by the supersymmetric models, it is shown that the Q-ball
matter depends additively on individual CP phases, whereas mass per unit charge
in the Q-ball depends only on the relative phases. There are regions of the
parameter space where there is no stable Q-ball solution in the CP-conserving
limit whereas finite CP phases induce a stable Q-ball.
| [
{
"created": "Fri, 7 Apr 2000 13:46:07 GMT",
"version": "v1"
}
] | 2009-10-31 | [
[
"Boz",
"M.",
"",
"Hacettepe"
],
[
"Demir",
"D. A.",
"",
"ICTP"
],
[
"Pak",
"N. K.",
"",
"METU"
]
] | Q-balls generically exist in the supersymmetric extensions of the standard model. Taking into account the additional sources of CP violation, which are naturally accomodated by the supersymmetric models, it is shown that the Q-ball matter depends additively on individual CP phases, whereas mass per unit charge in the Q-ball depends only on the relative phases. There are regions of the parameter space where there is no stable Q-ball solution in the CP-conserving limit whereas finite CP phases induce a stable Q-ball. |
1801.01361 | Da-Xin Zhang | Xian-Zheng Bai and Da-Xin Zhang | Goldstone Modes in Renormalizable Supersymmetric SO(10) Model | 27 pages. Only arXiv number for [38] added | null | 10.1140/epjc/s10052-018-5726-z | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We solve the Goldstone modes in the renormalizable SUSY SO(10) model with
general couplings. The Goldstones are expressed by the Vacuum Expectation
Values and the Clebsch-Gordan coefficients of relevant symmetries without
explicit dependence on the parameters of the model.
| [
{
"created": "Thu, 4 Jan 2018 14:17:00 GMT",
"version": "v1"
},
{
"created": "Mon, 8 Jan 2018 02:36:21 GMT",
"version": "v2"
}
] | 2018-04-18 | [
[
"Bai",
"Xian-Zheng",
""
],
[
"Zhang",
"Da-Xin",
""
]
] | We solve the Goldstone modes in the renormalizable SUSY SO(10) model with general couplings. The Goldstones are expressed by the Vacuum Expectation Values and the Clebsch-Gordan coefficients of relevant symmetries without explicit dependence on the parameters of the model. |
hep-ph/9901404 | Villante Francesco | E. Lisi, Subir Sarkar and F.L. Villante | Big bang nucleosynthesis limit on N_nu | 21 pages (RevTex), incl. 8 figures (epsf); to appear in Phys. ReV. D.
Typos corrected; minor change in referencing | Phys.Rev.D59:123520,1999 | 10.1103/PhysRevD.59.123520 | null | hep-ph astro-ph | null | Recently we presented a simple method for determining the correlated
uncertainties of the light element abundances expected from big bang
nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. We
now extend this approach to consider departures from the Standard Model, in
particular to constrain any new light degrees of freedom present in the thermal
plasma during nucleosynthesis. Since the observational situation regarding the
inferred primordial abundances has not yet stabilized, we present illustrative
bounds on the equivalent number of neutrino species N_nu for various
combinations of individual abundance determinations. Our 95% C.L. bounds on
N_nu range between 2 and 4, and can easily be reevaluated using the technique
provided when the abundances are known more accurately.
| [
{
"created": "Mon, 25 Jan 1999 16:23:24 GMT",
"version": "v1"
},
{
"created": "Mon, 19 Apr 1999 15:34:56 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Lisi",
"E.",
""
],
[
"Sarkar",
"Subir",
""
],
[
"Villante",
"F. L.",
""
]
] | Recently we presented a simple method for determining the correlated uncertainties of the light element abundances expected from big bang nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. We now extend this approach to consider departures from the Standard Model, in particular to constrain any new light degrees of freedom present in the thermal plasma during nucleosynthesis. Since the observational situation regarding the inferred primordial abundances has not yet stabilized, we present illustrative bounds on the equivalent number of neutrino species N_nu for various combinations of individual abundance determinations. Our 95% C.L. bounds on N_nu range between 2 and 4, and can easily be reevaluated using the technique provided when the abundances are known more accurately. |
0812.4260 | Alexandre Kisselev | A.V. Kisselev and V.A. Petrov | Can universality of the QCD evolution be checked in W boson decays into
hadrons? | 14 pages, 7 figures | J.Phys.G36:085007,2009 | 10.1088/0954-3899/36/8/085007 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Hadron multiplicity from $W$ boson is calculated in pQCD. The agreement of
our theoretical predictions with the LEP data says in favor of universality of
the QCD evolution in hard processes.
| [
{
"created": "Mon, 22 Dec 2008 18:04:24 GMT",
"version": "v1"
}
] | 2009-07-22 | [
[
"Kisselev",
"A. V.",
""
],
[
"Petrov",
"V. A.",
""
]
] | Hadron multiplicity from $W$ boson is calculated in pQCD. The agreement of our theoretical predictions with the LEP data says in favor of universality of the QCD evolution in hard processes. |
2311.13658 | James Maxwell | Francesca Chadha-Day, James Maxwell and Jessica Turner | ALP Anarchy | 19 pages, 7 figures | null | null | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | String theory models generically predict the existence of multiple axion-like
particle (ALP) fields, yet the majority of both theoretical and experimental
works have assumed only one ALP. In this paper, we discuss the phenomenology of
systems with multiple ALPs that can undergo oscillations akin to neutrino
oscillations. Motivated by this effect, we extend the anarchy framework, which
has been used to predict neutrino oscillation parameters, to generate the
parameters of many ALP systems. We explore the phenomenology of these ALP
anarchy models in some of the leading ALP search strategies, including the CERN
Axion Solar Telescope, magnetic white dwarfs and the gamma-ray spectra of
distant blazars. We include both the ALP-photon and the ALP-electron coupling.
We find that ALP anarchy models predict drastically different results than
single ALP models.
| [
{
"created": "Wed, 22 Nov 2023 19:19:49 GMT",
"version": "v1"
}
] | 2023-11-27 | [
[
"Chadha-Day",
"Francesca",
""
],
[
"Maxwell",
"James",
""
],
[
"Turner",
"Jessica",
""
]
] | String theory models generically predict the existence of multiple axion-like particle (ALP) fields, yet the majority of both theoretical and experimental works have assumed only one ALP. In this paper, we discuss the phenomenology of systems with multiple ALPs that can undergo oscillations akin to neutrino oscillations. Motivated by this effect, we extend the anarchy framework, which has been used to predict neutrino oscillation parameters, to generate the parameters of many ALP systems. We explore the phenomenology of these ALP anarchy models in some of the leading ALP search strategies, including the CERN Axion Solar Telescope, magnetic white dwarfs and the gamma-ray spectra of distant blazars. We include both the ALP-photon and the ALP-electron coupling. We find that ALP anarchy models predict drastically different results than single ALP models. |
1109.1563 | Daniel Noonan | Philip Baringer, Kyoungchul Kong, Mathew McCaskey, Daniel Noonan | Revisiting Combinatorial Ambiguities at Hadron Colliders with MT2 | 20 pages, 7 figures, 10 tables | JHEP 1110 (2011) 101 | 10.1007/JHEP10(2011)101 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present a method to resolve combinatorial issues in multi-particle final
states at hadron colliders. The use of kinematic variables such as MT2 and
invariant mass significantly reduces combinatorial ambiguities in the signal,
but at a cost of losing statistics. We illustrate this idea with gluino pair
production leading to 4 jets $+\met$ in the final state as well as $t\bar{t}$
production in the dilepton channel. Compared to results in recent studies, our
method provides greater efficiency with similar purity
| [
{
"created": "Wed, 7 Sep 2011 20:01:40 GMT",
"version": "v1"
}
] | 2015-05-30 | [
[
"Baringer",
"Philip",
""
],
[
"Kong",
"Kyoungchul",
""
],
[
"McCaskey",
"Mathew",
""
],
[
"Noonan",
"Daniel",
""
]
] | We present a method to resolve combinatorial issues in multi-particle final states at hadron colliders. The use of kinematic variables such as MT2 and invariant mass significantly reduces combinatorial ambiguities in the signal, but at a cost of losing statistics. We illustrate this idea with gluino pair production leading to 4 jets $+\met$ in the final state as well as $t\bar{t}$ production in the dilepton channel. Compared to results in recent studies, our method provides greater efficiency with similar purity |
1912.06509 | Michael Seymour | Johannes Bellm, Gavin Bewick, Silvia Ferrario Ravasio, Stefan Gieseke,
David Grellscheid, Patrick Kirchgaesser, Mohammad R. Masouminia, Graeme Nail,
Andreas Papaefstathiou, Simon Platzer, Michael Rauch, Christian Reuschle,
Peter Richardson, Michael H. Seymour, Andrzej Siodmok and Stephen Webster | Herwig 7.2 Release Note | 7 pages, 5 figures. Herwig is available from
https://herwig.hepforge.org. arXiv admin note: text overlap with
arXiv:1705.06919 | null | 10.1140/epjc/s10052-020-8011-x | MAN/HEP/2019/011, CERN-TH-2019-213, IFJPAN-IV-2019-18,
HERWIG-2019-02, UWTHPH-19-36, KA-TP-24-2019, LU-TP 19-57, MCnet-19-28,
IPPP/19/91 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | A new release of the Monte Carlo event generator Herwig (version 7.2) is now
available. This version introduces a number of improvements, notably:
improvements to the simulation of multiple-parton interactions, including
diffractive processes; a new model for baryonic colour re-connection; spin
correlations in both the dipole and angular-ordered parton showers;
improvements to strangeness production; an improved choice of evolution
variable in the angular-ordered parton shower; support for generic Lorentz
structures in BSM models.
| [
{
"created": "Thu, 12 Dec 2019 18:00:32 GMT",
"version": "v1"
}
] | 2020-06-24 | [
[
"Bellm",
"Johannes",
""
],
[
"Bewick",
"Gavin",
""
],
[
"Ravasio",
"Silvia Ferrario",
""
],
[
"Gieseke",
"Stefan",
""
],
[
"Grellscheid",
"David",
""
],
[
"Kirchgaesser",
"Patrick",
""
],
[
"Masouminia",
"Moham... | A new release of the Monte Carlo event generator Herwig (version 7.2) is now available. This version introduces a number of improvements, notably: improvements to the simulation of multiple-parton interactions, including diffractive processes; a new model for baryonic colour re-connection; spin correlations in both the dipole and angular-ordered parton showers; improvements to strangeness production; an improved choice of evolution variable in the angular-ordered parton shower; support for generic Lorentz structures in BSM models. |
0909.5454 | Kristian McDonald | Kristian L. McDonald | Warping, Extra Dimensions and a Slice of AdS_d | 30 pages, no figures | Phys.Rev.D81:024006,2010 | 10.1103/PhysRevD.81.024006 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inspired by the Randall-Sundrum (RS) framework we consider a number of
phenomenologically relevant model building questions on a slice of compactified
AdS_d for d >5. Such spaces are interesting as they enable one to realize the
weak scale via warping. We perform the Kaluza-Klein (KK) reduction for
gravitons and bulk vectors in these spaces and for the case of AdS_6 consider
the KK spectrum of gauge-scalars. We further obtain the KK towers for bulk
fermions on a slice of AdS_7 and AdS_9 and show that the RS approach to flavor
generalizes to these spaces with the localization of chiral zero mode fermions
controlled by their bulk Dirac mass parameters. However for the
phenomenologically interesting case where the transverse radius is R^{-1}\sim
TeV we show that bulk Standard Model fields are not viable due to a resulting
volume suppression of the gauge coupling constants. A similar suppression
occurs for the case of UV localization. Thus it seems that the Standard Model
fields should be confined to the infrared brane in such spaces. Sterile fields
and extended gauge sectors may propagate in the bulk with the gauge-coupling
volume suppression experienced by the latter motivating a weak coupling to
Standard Model fields. We also discuss some issues regarding the effective 4D
theory description in these spaces.
| [
{
"created": "Tue, 29 Sep 2009 22:07:15 GMT",
"version": "v1"
}
] | 2010-04-06 | [
[
"McDonald",
"Kristian L.",
""
]
] | Inspired by the Randall-Sundrum (RS) framework we consider a number of phenomenologically relevant model building questions on a slice of compactified AdS_d for d >5. Such spaces are interesting as they enable one to realize the weak scale via warping. We perform the Kaluza-Klein (KK) reduction for gravitons and bulk vectors in these spaces and for the case of AdS_6 consider the KK spectrum of gauge-scalars. We further obtain the KK towers for bulk fermions on a slice of AdS_7 and AdS_9 and show that the RS approach to flavor generalizes to these spaces with the localization of chiral zero mode fermions controlled by their bulk Dirac mass parameters. However for the phenomenologically interesting case where the transverse radius is R^{-1}\sim TeV we show that bulk Standard Model fields are not viable due to a resulting volume suppression of the gauge coupling constants. A similar suppression occurs for the case of UV localization. Thus it seems that the Standard Model fields should be confined to the infrared brane in such spaces. Sterile fields and extended gauge sectors may propagate in the bulk with the gauge-coupling volume suppression experienced by the latter motivating a weak coupling to Standard Model fields. We also discuss some issues regarding the effective 4D theory description in these spaces. |
2004.03160 | Gayatri Ghosh Dr. | Gayatri Ghosh | Significance of broken $ \mu-\tau $ Symmetry in correlating $
\delta_{CP} $, $ \theta_{13} $, Lightest neutrino Mass and neutrinoless
double beta decay $ 0\nu\beta\beta $ | 22 pages, 20 figures | Adv.High Energy Phys. 2021 (2021) 9563917 | 10.1155/2021/9563917 | null | hep-ph | http://creativecommons.org/licenses/by/4.0/ | Leptonic CP Violating Phase $ \delta_{CP} $ in the light neutrino sector and
leptogenesis via present matter antimatter asymmetry of the Universe entails
each other. Probing CP violation in light neutrino oscillation is one of the
challenging tasks today. The reactor mixing angle $ \theta_{13} $ measured in
reactor experiments, LBL, DUNE with high precision in neutrino experiments
indicates towards the vast dimension of scope to detect $ \delta_{CP} $. The
correlation between leptonic Dirac CPV phase $ \delta_{CP} $, reactor mixing
angle $ \theta_{13} $, lightest neutrino mass $ m_{1} $ and matter antimatter
asymmetry of the Universe within the framework of $ \mu-\tau $ symmetry
breaking assuming the type I seesaw dominance is extensively studied here.
Small tiny breaking of the $ \mu-\tau $ symmetry allows a large Dirac CP
violating phase in neutrino oscillation which in turn is characterised by
awareness of measured value of $ \theta_{13} $ and to provide a hint towards a
better understanding of the experimentally observed near maximal value of $
\nu_{\mu} -\nu_{\tau} $ mixing angle $ \theta_{23}\simeq \frac{\pi}{4}$.
Precise breaking of the $ \mu-\tau $ symmetry is achieved by adding a 120 plet
Higgs to the 10 $+$ $\bar{126}$ dimensional representation of Higgs. The
estimated three dimensional density parameter space of lightest neutrino mass $
m_{1} $, $ \delta_{CP} $, reactor mixing angle $ \theta_{13} $, is constrained
here for the requirement of producing the observed value of baryon asymmetry of
the Universe through the mechanism of leptogenesis. Carrying out numerical
analysis the allowed parameter space of $ m_{1} $, $ \delta_{CP} $, $
\theta_{13} $, is found out which can produce the observed baryon to photon
density ratio of the Universe.
| [
{
"created": "Tue, 7 Apr 2020 07:09:12 GMT",
"version": "v1"
},
{
"created": "Mon, 13 Apr 2020 08:24:15 GMT",
"version": "v2"
}
] | 2021-03-24 | [
[
"Ghosh",
"Gayatri",
""
]
] | Leptonic CP Violating Phase $ \delta_{CP} $ in the light neutrino sector and leptogenesis via present matter antimatter asymmetry of the Universe entails each other. Probing CP violation in light neutrino oscillation is one of the challenging tasks today. The reactor mixing angle $ \theta_{13} $ measured in reactor experiments, LBL, DUNE with high precision in neutrino experiments indicates towards the vast dimension of scope to detect $ \delta_{CP} $. The correlation between leptonic Dirac CPV phase $ \delta_{CP} $, reactor mixing angle $ \theta_{13} $, lightest neutrino mass $ m_{1} $ and matter antimatter asymmetry of the Universe within the framework of $ \mu-\tau $ symmetry breaking assuming the type I seesaw dominance is extensively studied here. Small tiny breaking of the $ \mu-\tau $ symmetry allows a large Dirac CP violating phase in neutrino oscillation which in turn is characterised by awareness of measured value of $ \theta_{13} $ and to provide a hint towards a better understanding of the experimentally observed near maximal value of $ \nu_{\mu} -\nu_{\tau} $ mixing angle $ \theta_{23}\simeq \frac{\pi}{4}$. Precise breaking of the $ \mu-\tau $ symmetry is achieved by adding a 120 plet Higgs to the 10 $+$ $\bar{126}$ dimensional representation of Higgs. The estimated three dimensional density parameter space of lightest neutrino mass $ m_{1} $, $ \delta_{CP} $, reactor mixing angle $ \theta_{13} $, is constrained here for the requirement of producing the observed value of baryon asymmetry of the Universe through the mechanism of leptogenesis. Carrying out numerical analysis the allowed parameter space of $ m_{1} $, $ \delta_{CP} $, $ \theta_{13} $, is found out which can produce the observed baryon to photon density ratio of the Universe. |
2211.11789 | Alba Soto-Ontoso | Leticia Cunqueiro, Davide Napoletano and Alba Soto-Ontoso | Dead-cone searches in heavy-ion collisions using the jet tree | v2: fixed typo in vacuum splitting function. Conclusions remain
unchanged | null | 10.1103/PhysRevD.107.094008 | null | hep-ph hep-ex nucl-ex nucl-th | http://creativecommons.org/licenses/by/4.0/ | We explore the possibility of using the dead cone of heavy quarks as a region
of the Lund plane where medium-induced gluon radiation can be isolated and
characterised. The filling of the dead cone by medium-induced gluons is
expected to be the result of the interplay between the minimum angle of such
radiation due to transverse momentum broadening and the dead-cone angle. Since
the measurement of a fully corrected Lund plane in heavy-ion collisions is
currently challenging, we propose to use jet grooming techniques to identify a
particular splitting in the jet tree that is both perturbative and sensitive to
the dead-cone effect. To that end, we propose a new jet substructure groomer,
dubbed Late-$k_t$, that selects the most collinear splitting in a QCD jet above
a certain transverse momentum cutoff $k_{t,\rm{cut}}$. The role of
$k_{t,\rm{cut}}$ is to guarantee perturbative splittings, while selecting the
most collinear splitting enhances the sensitivity to mass effects. As a proof
of concept, we study the angular distribution of the splitting tagged by
Late-$k_t$ both analytically and with Monte Carlo simulations. First, we derive
the logarithmic resummation structure in vacuum and demonstrate its capability
to distinguish between inclusive and heavy-flavoured jets. Next, we extend the
calculation for in-medium jets and show that medium-induced emissions lead to
an enhancement of collinear emissions below the dead cone angle. Numerically,
we demonstrate an excellent resilience of Late-$k_t$ against uncorrelated
thermal background, thus confirming this observable as a potential candidate to
unveil medium dynamics around the dead cone regime.
| [
{
"created": "Mon, 21 Nov 2022 19:00:07 GMT",
"version": "v1"
},
{
"created": "Mon, 20 Mar 2023 19:52:12 GMT",
"version": "v2"
}
] | 2023-05-17 | [
[
"Cunqueiro",
"Leticia",
""
],
[
"Napoletano",
"Davide",
""
],
[
"Soto-Ontoso",
"Alba",
""
]
] | We explore the possibility of using the dead cone of heavy quarks as a region of the Lund plane where medium-induced gluon radiation can be isolated and characterised. The filling of the dead cone by medium-induced gluons is expected to be the result of the interplay between the minimum angle of such radiation due to transverse momentum broadening and the dead-cone angle. Since the measurement of a fully corrected Lund plane in heavy-ion collisions is currently challenging, we propose to use jet grooming techniques to identify a particular splitting in the jet tree that is both perturbative and sensitive to the dead-cone effect. To that end, we propose a new jet substructure groomer, dubbed Late-$k_t$, that selects the most collinear splitting in a QCD jet above a certain transverse momentum cutoff $k_{t,\rm{cut}}$. The role of $k_{t,\rm{cut}}$ is to guarantee perturbative splittings, while selecting the most collinear splitting enhances the sensitivity to mass effects. As a proof of concept, we study the angular distribution of the splitting tagged by Late-$k_t$ both analytically and with Monte Carlo simulations. First, we derive the logarithmic resummation structure in vacuum and demonstrate its capability to distinguish between inclusive and heavy-flavoured jets. Next, we extend the calculation for in-medium jets and show that medium-induced emissions lead to an enhancement of collinear emissions below the dead cone angle. Numerically, we demonstrate an excellent resilience of Late-$k_t$ against uncorrelated thermal background, thus confirming this observable as a potential candidate to unveil medium dynamics around the dead cone regime. |
0810.2623 | Lars Kyllingstad | Lars Kyllingstad | Screened perturbation theory at four loops | Talk given at Strong and Electroweak Matter 2008, Amsterdam, Aug.
25-29 2008. 4 pages, 1 figure | Nucl. Phys A820, 167c (2009) | 10.1016/j.nuclphysa.2009.01.041 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the thermodynamics of massless phi-fourth theory using screened
perturbation theory, which is a way to systematically reorganise the
perturbative series. The free energy and pressure are calculated through four
loops in a double expansion in powers of g^2 and m/T, where m is a thermal mass
of order gT. The result is truncated at order g^7. We find that the convergence
properties are significantly improved compared to the weak-coupling expansion.
| [
{
"created": "Wed, 15 Oct 2008 10:52:05 GMT",
"version": "v1"
}
] | 2009-03-19 | [
[
"Kyllingstad",
"Lars",
""
]
] | We study the thermodynamics of massless phi-fourth theory using screened perturbation theory, which is a way to systematically reorganise the perturbative series. The free energy and pressure are calculated through four loops in a double expansion in powers of g^2 and m/T, where m is a thermal mass of order gT. The result is truncated at order g^7. We find that the convergence properties are significantly improved compared to the weak-coupling expansion. |
0812.2569 | Tatsuru Kikuchi | Tatsuru Kikuchi | A solution to the little hierarchy problem in a partly N=2 extension of
the MSSM | 9 pages, no figure | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We extend a model of the Dirac gauginos, which originate from N=2
supersymmetry (SUSY) for the gauge sector, such that the N=2 SUSY is imposed
also to the sfermion sector but only for the 3rd generation squarks and
sleptons. In addition to the N=2 supersymmetry, our model is constructed based
on the SU(3)c times SU(3)L times U(1)' gauge symmetry. By this extension, the
dominant source of radiative correction to the Higgs mass squared coming from
the stop loop becomes controllable based on the enhanced symmetry. Then it
becomes a viable model which provides a solution to the little hierarchy
problem in SUSY models. Even in the original scenario, the Dirac gauginos can
be superheavy, of order 10 TeV or so, while keeping the scalar masses at the
weak scale. This possibility is phenomenologically interesting because it can
suppress the unwanted flavor changing processes. And in scope of the LHC, this
scenario can have a very distinct signature related to the exotic sfermions
which are accompanied as the N=2 superpartners as well as the Dirac gauginos.
| [
{
"created": "Sat, 13 Dec 2008 17:49:45 GMT",
"version": "v1"
}
] | 2008-12-16 | [
[
"Kikuchi",
"Tatsuru",
""
]
] | We extend a model of the Dirac gauginos, which originate from N=2 supersymmetry (SUSY) for the gauge sector, such that the N=2 SUSY is imposed also to the sfermion sector but only for the 3rd generation squarks and sleptons. In addition to the N=2 supersymmetry, our model is constructed based on the SU(3)c times SU(3)L times U(1)' gauge symmetry. By this extension, the dominant source of radiative correction to the Higgs mass squared coming from the stop loop becomes controllable based on the enhanced symmetry. Then it becomes a viable model which provides a solution to the little hierarchy problem in SUSY models. Even in the original scenario, the Dirac gauginos can be superheavy, of order 10 TeV or so, while keeping the scalar masses at the weak scale. This possibility is phenomenologically interesting because it can suppress the unwanted flavor changing processes. And in scope of the LHC, this scenario can have a very distinct signature related to the exotic sfermions which are accompanied as the N=2 superpartners as well as the Dirac gauginos. |
1805.11285 | Li-Ye Xiao | Li-Ye Xiao and Xian-Hui Zhong | A possible interpretation of the newly observed $\Omega(2012)$ state | 6 pages, 2 figures | Phys. Rev. D 98, 034004 (2018) | 10.1103/PhysRevD.98.034004 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Inspired by the newly observed $\Omega(2012)$ state at Belle II, we
investigate the two-body strong decays of $\Omega$ baryons up to $N=2$ shell
within the chiral quark model. Our results indicate that: (i) the newly
observed $\Omega(2012)$ state could be assigned to the spin-parity $J^P=3/2^-$
state $|70,^210,1,1,\frac{3}{2}^-\rangle$ and the experimental data can be
reasonably described. However, the spin-parity $J^P=1/2^-$ state
$|70,^210,1,1,\frac{1}{2}^-\rangle$ and spin-parity $J^P=3/2^+$ state
$|56,^410,2,0,\frac{3}{2}^+\rangle$ can't be completely excluded. (ii) The
$D$-wave states in the $N=2$ shell are most likely to be narrow states with a
width of dozens of MeV and have a good potential to be observed in the $\Xi K$
and/or $\Xi(1530)K$ channels in future experiments. The $\Omega(2250)$
resonance listed in PDG may be a good candidate of the $J^P=5/2^+$ $1D$ wave
state $|56,^410,2,2,5/2^+\rangle$.
| [
{
"created": "Tue, 29 May 2018 07:55:43 GMT",
"version": "v1"
}
] | 2018-08-08 | [
[
"Xiao",
"Li-Ye",
""
],
[
"Zhong",
"Xian-Hui",
""
]
] | Inspired by the newly observed $\Omega(2012)$ state at Belle II, we investigate the two-body strong decays of $\Omega$ baryons up to $N=2$ shell within the chiral quark model. Our results indicate that: (i) the newly observed $\Omega(2012)$ state could be assigned to the spin-parity $J^P=3/2^-$ state $|70,^210,1,1,\frac{3}{2}^-\rangle$ and the experimental data can be reasonably described. However, the spin-parity $J^P=1/2^-$ state $|70,^210,1,1,\frac{1}{2}^-\rangle$ and spin-parity $J^P=3/2^+$ state $|56,^410,2,0,\frac{3}{2}^+\rangle$ can't be completely excluded. (ii) The $D$-wave states in the $N=2$ shell are most likely to be narrow states with a width of dozens of MeV and have a good potential to be observed in the $\Xi K$ and/or $\Xi(1530)K$ channels in future experiments. The $\Omega(2250)$ resonance listed in PDG may be a good candidate of the $J^P=5/2^+$ $1D$ wave state $|56,^410,2,2,5/2^+\rangle$. |
hep-ph/0110131 | Lianshou Liu | Liu Fuming, Liao Hongbo, Liu Ming, Liu Feng, Liu Lianshou | A Monte Carlo Study of Erraticity Behavior in Nucleus-Nucleus Collisions
at High Energies | 9 pages, 4 figures (in eps form) | Phys.Lett. B516 (2001) 293-298 | 10.1016/S0370-2693(01)00960-1 | HZPP0101 | hep-ph | null | It is demonstrated using Monte Carlo simulation that in different
nucleus$-$nucleus collision samples, the increase of the fluctuation of event
factorial moments with decreasing phase space scale, called erraticity, is
still dominated by the statistical fluctuations. This result does not depend on
the Monte Carlo models. Nor does it depend on the concrete conditions, e.g. the
collision energy, the mass of colliding nuclei, the cut of phase space, etc..
This means that the erraticity method is sensitive to the appearance of novel
physics in the central collisions of heavy nuclei.
| [
{
"created": "Wed, 10 Oct 2001 00:29:06 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Fuming",
"Liu",
""
],
[
"Hongbo",
"Liao",
""
],
[
"Ming",
"Liu",
""
],
[
"Feng",
"Liu",
""
],
[
"Lianshou",
"Liu",
""
]
] | It is demonstrated using Monte Carlo simulation that in different nucleus$-$nucleus collision samples, the increase of the fluctuation of event factorial moments with decreasing phase space scale, called erraticity, is still dominated by the statistical fluctuations. This result does not depend on the Monte Carlo models. Nor does it depend on the concrete conditions, e.g. the collision energy, the mass of colliding nuclei, the cut of phase space, etc.. This means that the erraticity method is sensitive to the appearance of novel physics in the central collisions of heavy nuclei. |
hep-ph/0405287 | Peter Watson | Peter Watson and Wolfgang Cassing (Univ. Giessen) | Unquenching the Quark-Antiquark Green's Function | 21 pages, 13 figures | Few Body Syst. 35 (2004) 99-115 | 10.1007/s00601-004-0063-1 | null | hep-ph | null | We propose a nonperturbative resummation scheme for the four-point connected
quark-antiquark Green's function $G^4$ that shows how the Bethe-Salpeter
equation may be `unquenched' with respect to quark-antiquark loops. This
mechanism allows to dynamically account for hadronic meson decays and
multiquark structures whilst respecting the underlying symmetries. An initial
approximation to the four-point Schwinger-Dyson equation -- suitable for
phenomenological application -- is examined numerically in a couple of aspects.
It is demonstrated that this approximation explicitly maintains the correct
asymptotic limits and contains the physical resonance structures in the near
timelike region in the quark-antiquark channel whereas no resonances are found
in the diquark channel, respectively.
| [
{
"created": "Fri, 28 May 2004 15:24:25 GMT",
"version": "v1"
}
] | 2015-06-25 | [
[
"Watson",
"Peter",
"",
"Univ. Giessen"
],
[
"Cassing",
"Wolfgang",
"",
"Univ. Giessen"
]
] | We propose a nonperturbative resummation scheme for the four-point connected quark-antiquark Green's function $G^4$ that shows how the Bethe-Salpeter equation may be `unquenched' with respect to quark-antiquark loops. This mechanism allows to dynamically account for hadronic meson decays and multiquark structures whilst respecting the underlying symmetries. An initial approximation to the four-point Schwinger-Dyson equation -- suitable for phenomenological application -- is examined numerically in a couple of aspects. It is demonstrated that this approximation explicitly maintains the correct asymptotic limits and contains the physical resonance structures in the near timelike region in the quark-antiquark channel whereas no resonances are found in the diquark channel, respectively. |
1704.06884 | Hiroki Matsui | Kazunori Kohri and Hiroki Matsui | Electroweak Vacuum Instability and Renormalized Vacuum Field
Fluctuations in Friedmann-Lemaitre-Robertson-Walker Background | 16 pages, References added, Published version in PRD | Phys. Rev. D 98, 103521 (2018) | 10.1103/PhysRevD.98.103521 | KEK-TH-1965, KEK-Cosmo-201 | hep-ph astro-ph.CO gr-qc hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The cosmological Higgs vacuum stability has been an attractive research
subject and it is crucial to accurately follow the development of the Higgs
fluctuations. In this work, we thoroughly investigate how the vacuum
fluctuations of the Higgs field affect the stability of the electroweak vacuum
in Friedmann-Lemaitre-Robertson-Walker (FLRW) background. Adopting adiabatic
(WKB) approximation or adiabatic regularization methods, we clearly show that
vacuum fluctuations of the Higgs field in the FLRW background depend on the
curvature and also masses of the Higgs or other scalar fields. The Higgs
fluctuations can generate true vacuum bubbles and trigger off a collapse of the
electroweak vacuum. Furthermore we clearly show that the effective Higgs
potential in the FLRW background is modified by the Higgs vacuum fluctuations.
The vacuum fluctuations of the standard model fields can stabilize or
destabilize the effective Higgs potential through backreaction effects.
Considering the improved effective Higgs potential with the Higgs vacuum
fluctuations $\left< { \delta \phi }^{ 2 } \right>$ in various backgrounds, we
provide new cosmological constraints on the mass of the Higgs-coupled scalar
fields and a quantitative description of the Higgs stability in the FLRW
background.
| [
{
"created": "Sun, 23 Apr 2017 05:45:55 GMT",
"version": "v1"
},
{
"created": "Tue, 21 Aug 2018 08:09:35 GMT",
"version": "v2"
},
{
"created": "Thu, 22 Nov 2018 13:47:18 GMT",
"version": "v3"
}
] | 2018-11-26 | [
[
"Kohri",
"Kazunori",
""
],
[
"Matsui",
"Hiroki",
""
]
] | The cosmological Higgs vacuum stability has been an attractive research subject and it is crucial to accurately follow the development of the Higgs fluctuations. In this work, we thoroughly investigate how the vacuum fluctuations of the Higgs field affect the stability of the electroweak vacuum in Friedmann-Lemaitre-Robertson-Walker (FLRW) background. Adopting adiabatic (WKB) approximation or adiabatic regularization methods, we clearly show that vacuum fluctuations of the Higgs field in the FLRW background depend on the curvature and also masses of the Higgs or other scalar fields. The Higgs fluctuations can generate true vacuum bubbles and trigger off a collapse of the electroweak vacuum. Furthermore we clearly show that the effective Higgs potential in the FLRW background is modified by the Higgs vacuum fluctuations. The vacuum fluctuations of the standard model fields can stabilize or destabilize the effective Higgs potential through backreaction effects. Considering the improved effective Higgs potential with the Higgs vacuum fluctuations $\left< { \delta \phi }^{ 2 } \right>$ in various backgrounds, we provide new cosmological constraints on the mass of the Higgs-coupled scalar fields and a quantitative description of the Higgs stability in the FLRW background. |
hep-ph/0702150 | Are R. Raklev | J.M. Butterworth, J.R. Ellis and A.R. Raklev | Reconstructing Sparticle Mass Spectra using Hadronic Decays | 1+29 pages, 12 figures | JHEP 0705:033,2007 | 10.1088/1126-6708/2007/05/033 | CERN-PH-TH/2007-019 | hep-ph hep-ex | null | Most sparticle decay cascades envisaged at the Large Hadron Collider (LHC)
involve hadronic decays of intermediate particles. We use state-of-the art
techniques based on the \kt jet algorithm to reconstruct the resulting hadronic
final states for simulated LHC events in a number of benchmark supersymmetric
scenarios. In particular, we show that a general method of selecting
preferentially boosted massive particles such as W, Z or Higgs bosons decaying
to jets, using sub-jets found by the \kt algorithm, suppresses QCD backgrounds
and thereby enhances the observability of signals that would otherwise be
indistinct. Consequently, measurements of the supersymmetric mass spectrum at
the per-cent level can be obtained from cascades including the hadronic decays
of such massive intermediate bosons.
| [
{
"created": "Thu, 15 Feb 2007 12:34:44 GMT",
"version": "v1"
}
] | 2009-11-13 | [
[
"Butterworth",
"J. M.",
""
],
[
"Ellis",
"J. R.",
""
],
[
"Raklev",
"A. R.",
""
]
] | Most sparticle decay cascades envisaged at the Large Hadron Collider (LHC) involve hadronic decays of intermediate particles. We use state-of-the art techniques based on the \kt jet algorithm to reconstruct the resulting hadronic final states for simulated LHC events in a number of benchmark supersymmetric scenarios. In particular, we show that a general method of selecting preferentially boosted massive particles such as W, Z or Higgs bosons decaying to jets, using sub-jets found by the \kt algorithm, suppresses QCD backgrounds and thereby enhances the observability of signals that would otherwise be indistinct. Consequently, measurements of the supersymmetric mass spectrum at the per-cent level can be obtained from cascades including the hadronic decays of such massive intermediate bosons. |
hep-ph/0609219 | Vicente Vento | Vicente Vento | Glueball enhancement by color de-confinement | 9 pages, 4 figures | Phys.Rev.D75:055012,2007 | 10.1103/PhysRevD.75.055012 | FTUV-06-0922 | hep-ph nucl-th | null | High energy heavy ion collisions lead to the formation of a strong coupling
de-confined phase in which the lightest glueballs are numerous and stable. We
analyze how their properties manifest themselves in experimental spectra and
show that they provide a good signature for color de-confinement.
| [
{
"created": "Thu, 21 Sep 2006 08:48:23 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Vento",
"Vicente",
""
]
] | High energy heavy ion collisions lead to the formation of a strong coupling de-confined phase in which the lightest glueballs are numerous and stable. We analyze how their properties manifest themselves in experimental spectra and show that they provide a good signature for color de-confinement. |
1907.03676 | Hugues Beauchesne | Hugues Beauchesne and Yevgeny Kats | Searching for periodic signals in kinematic distributions using
continuous wavelet transforms | 22 pages, 7 figures, matches version published in EPJC | null | 10.1140/epjc/s10052-020-7746-8 | null | hep-ph hep-ex | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Many models of physics beyond the Standard Model include towers of particles
whose masses follow an approximately periodic pattern with little spacing
between them. These resonances might be too weak to detect individually, but
could be discovered as a group by looking for periodic signals in kinematic
distributions. The continuous wavelet transform, which indicates how much a
given frequency is present in a signal at a given time, is an ideal tool for
this. In this paper, we present a series of methods through which continuous
wavelet transforms can be used to discover periodic signals in kinematic
distributions. Some of these methods are based on a simple test statistic,
while others make use of machine learning techniques. Some of the methods are
meant to be used with a particular model in mind, while others are
model-independent. We find that continuous wavelet transforms can give bounds
comparable to current searches and, in some cases, be sensitive to signals that
would go undetected by standard experimental strategies.
| [
{
"created": "Mon, 8 Jul 2019 15:32:17 GMT",
"version": "v1"
},
{
"created": "Thu, 5 Mar 2020 10:28:18 GMT",
"version": "v2"
}
] | 2020-03-18 | [
[
"Beauchesne",
"Hugues",
""
],
[
"Kats",
"Yevgeny",
""
]
] | Many models of physics beyond the Standard Model include towers of particles whose masses follow an approximately periodic pattern with little spacing between them. These resonances might be too weak to detect individually, but could be discovered as a group by looking for periodic signals in kinematic distributions. The continuous wavelet transform, which indicates how much a given frequency is present in a signal at a given time, is an ideal tool for this. In this paper, we present a series of methods through which continuous wavelet transforms can be used to discover periodic signals in kinematic distributions. Some of these methods are based on a simple test statistic, while others make use of machine learning techniques. Some of the methods are meant to be used with a particular model in mind, while others are model-independent. We find that continuous wavelet transforms can give bounds comparable to current searches and, in some cases, be sensitive to signals that would go undetected by standard experimental strategies. |
0706.2914 | Irinel Caprini | Irinel Caprini, Jan Fischer | Comment on "Infrared freezing of Euclidean QCD observables" | null | Phys.Rev.D76:018501,2007 | 10.1103/PhysRevD.76.018501 | null | hep-ph | null | Recently, P. M. Brooks and C.J. Maxwell [Phys. Rev. D{\bf 74} 065012 (2006)]
claimed that the Landau pole of the one-loop coupling at $Q^2=\Lambda^2$ is
absent from the leading one-chain term in a skeleton expansion of the Euclidean
Adler ${\cal D}$ function. Moreover, in this approximation one has continuity
along the Euclidean axis and a smooth infrared freezing, properties known to be
satisfied by the "true" Adler function. We show that crucial in the derivation
of these results is the use of a modified Borel summation, which leads
simultaneously to the loss of another fundamental property of the true Adler
function: the analyticity implied by the K\"allen-Lehmann representation.
| [
{
"created": "Wed, 20 Jun 2007 05:06:19 GMT",
"version": "v1"
}
] | 2008-11-26 | [
[
"Caprini",
"Irinel",
""
],
[
"Fischer",
"Jan",
""
]
] | Recently, P. M. Brooks and C.J. Maxwell [Phys. Rev. D{\bf 74} 065012 (2006)] claimed that the Landau pole of the one-loop coupling at $Q^2=\Lambda^2$ is absent from the leading one-chain term in a skeleton expansion of the Euclidean Adler ${\cal D}$ function. Moreover, in this approximation one has continuity along the Euclidean axis and a smooth infrared freezing, properties known to be satisfied by the "true" Adler function. We show that crucial in the derivation of these results is the use of a modified Borel summation, which leads simultaneously to the loss of another fundamental property of the true Adler function: the analyticity implied by the K\"allen-Lehmann representation. |
1807.08976 | Byung-Geel Yu | Kook-Jin Kong and Byung-Geel Yu | Features of forward $\pi N$ scattering from a Reggeized model | 12 pages, 12 figures, 2 table | Phys. Rev. C 98, 045207 (2018) | 10.1103/PhysRevC.98.045207 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Charge exchange process $\pi^-p\to\pi^0n$ and elastic scatterings $\pi^\pm
p\to \pi^\pm p$ are investigated within the Regge framework where the
relativistic Born amplitude is reggeized for the $t$-channel meson exchange.
Charge exchange cross section is featured by the single $\rho$ exchange.
Additional correction by Regge cuts, $\rho$-$f_2$ and $\rho$-Pomeron, agree
with differential cross sections and new trajectory for the $\rho'(1450)$
exchange is attempted to reproduce polarization data. For the description of
elastic scattering data up to pion momentum $P_{\rm Lab}\approx 250$ GeV/c,
Pomeron exchange of the Donnachie-Landshoff type is newly constructed and
applied in this work. Elastic cross section data are well reproduced with the
dominance of $f_2$ and Pomeron exchanges in intermediate and high energies.
Analysis of nucleon resonances is presented to test the validity of the present
Regge framework below $W\leq2$ GeV.
| [
{
"created": "Tue, 24 Jul 2018 09:11:31 GMT",
"version": "v1"
},
{
"created": "Fri, 10 Aug 2018 16:07:16 GMT",
"version": "v2"
}
] | 2018-10-24 | [
[
"Kong",
"Kook-Jin",
""
],
[
"Yu",
"Byung-Geel",
""
]
] | Charge exchange process $\pi^-p\to\pi^0n$ and elastic scatterings $\pi^\pm p\to \pi^\pm p$ are investigated within the Regge framework where the relativistic Born amplitude is reggeized for the $t$-channel meson exchange. Charge exchange cross section is featured by the single $\rho$ exchange. Additional correction by Regge cuts, $\rho$-$f_2$ and $\rho$-Pomeron, agree with differential cross sections and new trajectory for the $\rho'(1450)$ exchange is attempted to reproduce polarization data. For the description of elastic scattering data up to pion momentum $P_{\rm Lab}\approx 250$ GeV/c, Pomeron exchange of the Donnachie-Landshoff type is newly constructed and applied in this work. Elastic cross section data are well reproduced with the dominance of $f_2$ and Pomeron exchanges in intermediate and high energies. Analysis of nucleon resonances is presented to test the validity of the present Regge framework below $W\leq2$ GeV. |
1805.03572 | Angel Salvador Miramontes L\'opez | A.S. Miramontes and H. Sanchis-Alepuz | Decay mechanisms in bound state interaction kernels | 6 pages, 4 figures. Proceedings of Excited QCD 2018 | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present progress on the study of decay-channel effects in the properties
of hadrons using covariant Bethe-Salpeter equations (BSEs). The main goal will
be to develop BSE kernels that contain explicit decay mechanisms. This will be
first explored in the meson sector where, for example, a kernel suitable to
study the rho meson should contain a virtual $\rho \rightarrow \pi + \pi$ decay
mechanism. This will be tackled by including explicit pion degrees of freedom
in addition to quarks and gluons.
| [
{
"created": "Wed, 9 May 2018 15:03:21 GMT",
"version": "v1"
}
] | 2018-05-10 | [
[
"Miramontes",
"A. S.",
""
],
[
"Sanchis-Alepuz",
"H.",
""
]
] | We present progress on the study of decay-channel effects in the properties of hadrons using covariant Bethe-Salpeter equations (BSEs). The main goal will be to develop BSE kernels that contain explicit decay mechanisms. This will be first explored in the meson sector where, for example, a kernel suitable to study the rho meson should contain a virtual $\rho \rightarrow \pi + \pi$ decay mechanism. This will be tackled by including explicit pion degrees of freedom in addition to quarks and gluons. |
hep-ph/0410361 | Nikonov Victor A. | V.V. Anisovich, L.G. Dakhno, V.N. Markov, V.A. Nikonov, A.V. Sarantsev | Charmed quark component of the photon wave function | 20 pages, 8 figures | Phys.Atom.Nucl. 68 (2005) 2081-2092; Yad.Fiz. 68 (2005) 2143-2154 | 10.1134/1.2149087 | null | hep-ph | null | We determine the c-anti-c component of the photon wave function on the basis
of (i) the data on the transitions e+ e- -> J/psi(3096), psi(3686), psi(4040),
psi(4415), (ii) partial widths of the two-photon decays eta_{c0}(2979),
chi_{c0}(3415), chi_{c2}(3556) -> gamma-gamma, and (iii) wave functions of the
charmonium states obtained by solving the Bethe-Salpeter equation for the
c-anti-c system. Using the obtained c-anti-c component of the photon wave
function we calculate the gamma-gamma decay partial widths for radial
excitation 2S state, eta_{c0}(3594) -> gamma-gamma, and 2P states
chi_{c0}(3849), chi_{c2}(3950) -> gamma-gamma.
| [
{
"created": "Wed, 27 Oct 2004 12:48:32 GMT",
"version": "v1"
}
] | 2009-11-10 | [
[
"Anisovich",
"V. V.",
""
],
[
"Dakhno",
"L. G.",
""
],
[
"Markov",
"V. N.",
""
],
[
"Nikonov",
"V. A.",
""
],
[
"Sarantsev",
"A. V.",
""
]
] | We determine the c-anti-c component of the photon wave function on the basis of (i) the data on the transitions e+ e- -> J/psi(3096), psi(3686), psi(4040), psi(4415), (ii) partial widths of the two-photon decays eta_{c0}(2979), chi_{c0}(3415), chi_{c2}(3556) -> gamma-gamma, and (iii) wave functions of the charmonium states obtained by solving the Bethe-Salpeter equation for the c-anti-c system. Using the obtained c-anti-c component of the photon wave function we calculate the gamma-gamma decay partial widths for radial excitation 2S state, eta_{c0}(3594) -> gamma-gamma, and 2P states chi_{c0}(3849), chi_{c2}(3950) -> gamma-gamma. |
1505.05804 | Martin Jung | Oscar Cat\`a and Martin Jung | Signatures of a nonstandard Higgs from flavor physics | 4 pages. v2: minor changes, references added | Phys. Rev. D 92, 055018 (2015) | 10.1103/PhysRevD.92.055018 | LMU-ASC 34/15, FLAVOUR(267104)-ERC-99 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We examine the constraints coming from incorporating the full Standard Model
gauge symmetry into the effective field theory description of flavor processes,
using semileptonic decays as paradigmatic examples. Depending on the dynamics
triggering electroweak symmetry breaking, different patterns of correlations
between the Wilson coefficients arise. Interestingly, this implies that flavor
experiments are capable of shedding light upon the nature of the Higgs boson
without actually requiring Higgs final states. Furthermore, the observed
correlations can simplify model-independent analyses of these decays.
| [
{
"created": "Thu, 21 May 2015 17:35:25 GMT",
"version": "v1"
},
{
"created": "Tue, 9 Jun 2015 19:56:00 GMT",
"version": "v2"
}
] | 2015-09-23 | [
[
"Catà",
"Oscar",
""
],
[
"Jung",
"Martin",
""
]
] | We examine the constraints coming from incorporating the full Standard Model gauge symmetry into the effective field theory description of flavor processes, using semileptonic decays as paradigmatic examples. Depending on the dynamics triggering electroweak symmetry breaking, different patterns of correlations between the Wilson coefficients arise. Interestingly, this implies that flavor experiments are capable of shedding light upon the nature of the Higgs boson without actually requiring Higgs final states. Furthermore, the observed correlations can simplify model-independent analyses of these decays. |
hep-ph/9403291 | Carsten Grosse-Knetter | Carsten Grosse-Knetter and Ingolf Kuss (Universitaet Bielefeld) | The Equivalence Theorem and Effective Lagrangians | 20 pages LaTeX, BI-TP 94/10 | Z.Phys. C66 (1995) 95-106 | 10.1007/BF01496584 | null | hep-ph | null | We point out that the equivalence theorem, which relates the amplitude for a
process with external longitudinally polarized vector bosons to the amplitude
in which the longitudinal vector bosons are replaced by the corresponding
pseudo-Goldstone bosons, is not valid for effective Lagrangians. However, a
more general formulation of this theorem also holds for effective interactions.
The generalized theorem can be utilized to determine the high-energy behaviour
of scattering processes just by power counting and to simplify the calculation
of the corresponding amplitudes. We apply this method to the phenomenologically
most interesting terms describing effective interactions of the electroweak
vector and Higgs bosons in order to examine their effects on vector-boson
scattering and on vector-boson-pair production in $f\bar{f}$ annihilation. The
use of the equivalence theorem in the literature is examined.
| [
{
"created": "Tue, 15 Mar 1994 18:24:46 GMT",
"version": "v1"
}
] | 2009-10-28 | [
[
"Grosse-Knetter",
"Carsten",
"",
"Universitaet Bielefeld"
],
[
"Kuss",
"Ingolf",
"",
"Universitaet Bielefeld"
]
] | We point out that the equivalence theorem, which relates the amplitude for a process with external longitudinally polarized vector bosons to the amplitude in which the longitudinal vector bosons are replaced by the corresponding pseudo-Goldstone bosons, is not valid for effective Lagrangians. However, a more general formulation of this theorem also holds for effective interactions. The generalized theorem can be utilized to determine the high-energy behaviour of scattering processes just by power counting and to simplify the calculation of the corresponding amplitudes. We apply this method to the phenomenologically most interesting terms describing effective interactions of the electroweak vector and Higgs bosons in order to examine their effects on vector-boson scattering and on vector-boson-pair production in $f\bar{f}$ annihilation. The use of the equivalence theorem in the literature is examined. |
hep-ph/9810258 | Wilhelmus van Neerven | V. Ravindran and W.L. van Neerven | Heavy flavour mass corrections to the longitudinal and transverse cross
sections in e^+e^- - collisions | 8 pages Latex, all compressed by uufiles | Phys.Lett.B445:206-213,1998 | 10.1016/S0370-2693(98)01441-5 | DESY 98-157 | hep-ph | null | The sentence, 7th line below Eq. (28), starting with "Further we exclude all
interference terms ...." is wrong and has been corrected. Eq. (33) :
f_k^{l,(i)} -> h_k^{l,(i)} i=0,1 Second line below Eq. (33) m_bar(m)=m is
replaced by m_bar(\mu_0)=\mu_0 with \mu_0=4.10 GeV and \mu_0=166.1 GeV for
bottom and top respectively. The numbers in the third column of tables 1 and 2
are a little bit changed.
| [
{
"created": "Tue, 6 Oct 1998 08:58:55 GMT",
"version": "v1"
},
{
"created": "Mon, 2 Nov 1998 20:39:07 GMT",
"version": "v2"
}
] | 2014-11-17 | [
[
"Ravindran",
"V.",
""
],
[
"van Neerven",
"W. L.",
""
]
] | The sentence, 7th line below Eq. (28), starting with "Further we exclude all interference terms ...." is wrong and has been corrected. Eq. (33) : f_k^{l,(i)} -> h_k^{l,(i)} i=0,1 Second line below Eq. (33) m_bar(m)=m is replaced by m_bar(\mu_0)=\mu_0 with \mu_0=4.10 GeV and \mu_0=166.1 GeV for bottom and top respectively. The numbers in the third column of tables 1 and 2 are a little bit changed. |
1902.01418 | Yonatan Kahn | Zachary Bogorad, Anson Hook, Yonatan Kahn, Yotam Soreq | Probing ALPs and the Axiverse with Superconducting Radiofrequency
Cavities | v2: 6+4 pages, 2+1 figures. Typos fixed, references added, matches
PRL version. v1: 7+2 pages, 2+1 figures | Phys. Rev. Lett. 123, 021801 (2019) | 10.1103/PhysRevLett.123.021801 | CERN-TH-2019-009 | hep-ph hep-ex physics.ins-det | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Axion-like particles (ALPs) with couplings to electromagnetism have long been
postulated as extensions to the Standard Model. String theory predicts an
"axiverse" of many light axions, some of which may make up the dark matter in
the universe and/or solve the strong CP problem. We propose a new experiment
using superconducting radiofrequency (SRF) cavities which is sensitive to light
ALPs independent of their contribution to the cosmic dark matter density.
Off-shell ALPs will source cubic nonlinearities in Maxwell's equations, such
that if a SRF cavity is pumped at frequencies $\omega_1$ and $\omega_2$, in the
presence of ALPs there will be power in modes with frequencies $2\omega_1 \pm
\omega_2$. Our setup is similar in spirit to light-shining-through-walls (LSW)
experiments, but because the pump field itself effectively converts the ALP
back to photons inside a single cavity, our sensitivity scales differently with
the strength of the external fields, allowing for superior reach as compared to
experiments like OSQAR while utilizing current technology. Furthermore, a
well-defined program of increasing sensitivity has a guaranteed physics result:
the first observation of the Euler-Heisenberg term of low-energy QED at
energies below the electron mass. We discuss how the ALP contribution may be
separated from the QED contribution by a suitable choice of pump modes and
cavity geometry, and conclude by describing the ultimate sensitivity of our
proposed program of experiments to ALPs.
| [
{
"created": "Mon, 4 Feb 2019 19:00:27 GMT",
"version": "v1"
},
{
"created": "Fri, 12 Jul 2019 19:59:03 GMT",
"version": "v2"
}
] | 2019-07-17 | [
[
"Bogorad",
"Zachary",
""
],
[
"Hook",
"Anson",
""
],
[
"Kahn",
"Yonatan",
""
],
[
"Soreq",
"Yotam",
""
]
] | Axion-like particles (ALPs) with couplings to electromagnetism have long been postulated as extensions to the Standard Model. String theory predicts an "axiverse" of many light axions, some of which may make up the dark matter in the universe and/or solve the strong CP problem. We propose a new experiment using superconducting radiofrequency (SRF) cavities which is sensitive to light ALPs independent of their contribution to the cosmic dark matter density. Off-shell ALPs will source cubic nonlinearities in Maxwell's equations, such that if a SRF cavity is pumped at frequencies $\omega_1$ and $\omega_2$, in the presence of ALPs there will be power in modes with frequencies $2\omega_1 \pm \omega_2$. Our setup is similar in spirit to light-shining-through-walls (LSW) experiments, but because the pump field itself effectively converts the ALP back to photons inside a single cavity, our sensitivity scales differently with the strength of the external fields, allowing for superior reach as compared to experiments like OSQAR while utilizing current technology. Furthermore, a well-defined program of increasing sensitivity has a guaranteed physics result: the first observation of the Euler-Heisenberg term of low-energy QED at energies below the electron mass. We discuss how the ALP contribution may be separated from the QED contribution by a suitable choice of pump modes and cavity geometry, and conclude by describing the ultimate sensitivity of our proposed program of experiments to ALPs. |
1009.0980 | Long-Fei Gan | Long-Fei Gan and Ming-Qiu Huang | QCD Sum Rule Analysis of Semileptonic $B_{s1}$, $B^{*}_{s2}$,
$B^{*}_{s0}$, and $B'_{s1}$ Decays in HQET | 18 pages, 8 eps figures, revised version accepted for publication in
Phys. Rev. D | Phys.Rev.D82:054035,2010 | 10.1103/PhysRevD.82.054035 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We present an analysis of semileptonic decays of orbitally, $P$-wave excited
$B_{s}$ meson states $B^{**}_{s}$, including the newly found narrow
$B_{s1}(5830)$ and $B^{*}_{s2}(5840)$ states, into low lying $D_{s}$ mesons
($D_{s}(1968)$, $D^{*}_{s}(2112)$, $D_{sJ}(2317)$, $D_{sJ}(2460)$) within the
framework of heavy quark effective theory. The relevant universal form factors
are estimated using QCD sum rules at the leading-order of the heavy quark
expansion. The decay widths are predicted and the branching ratios are
estimated.
| [
{
"created": "Mon, 6 Sep 2010 07:38:26 GMT",
"version": "v1"
}
] | 2014-11-21 | [
[
"Gan",
"Long-Fei",
""
],
[
"Huang",
"Ming-Qiu",
""
]
] | We present an analysis of semileptonic decays of orbitally, $P$-wave excited $B_{s}$ meson states $B^{**}_{s}$, including the newly found narrow $B_{s1}(5830)$ and $B^{*}_{s2}(5840)$ states, into low lying $D_{s}$ mesons ($D_{s}(1968)$, $D^{*}_{s}(2112)$, $D_{sJ}(2317)$, $D_{sJ}(2460)$) within the framework of heavy quark effective theory. The relevant universal form factors are estimated using QCD sum rules at the leading-order of the heavy quark expansion. The decay widths are predicted and the branching ratios are estimated. |
hep-ph/9605451 | Kiselev | V.V.Kiselev | Hard approximation in two-particle hadronic decays of B_c at large
recoils | 7 pages, 1 eps-figure, eqs.(4), (6) corrected, numerical estimates
changed | null | null | IHEP 96-41 | hep-ph | null | The two-particle decays of B_c^+ to psi pi^+(rho^+) and B_c^+ to eta_c
pi^+(rho^+) are considered in a way taking into account a soft binding of
quarks in the heavy quarkonia and a hard gluon exchange between the
constituents at large recoil momenta of psi(eta_c). An approximate double
enhancement of the amplitudes is found because of the nonspectator t-channel
contribution.
| [
{
"created": "Fri, 31 May 1996 09:04:13 GMT",
"version": "v1"
},
{
"created": "Wed, 5 Jun 1996 12:34:08 GMT",
"version": "v2"
},
{
"created": "Mon, 8 Oct 2001 11:12:43 GMT",
"version": "v3"
}
] | 2008-02-03 | [
[
"Kiselev",
"V. V.",
""
]
] | The two-particle decays of B_c^+ to psi pi^+(rho^+) and B_c^+ to eta_c pi^+(rho^+) are considered in a way taking into account a soft binding of quarks in the heavy quarkonia and a hard gluon exchange between the constituents at large recoil momenta of psi(eta_c). An approximate double enhancement of the amplitudes is found because of the nonspectator t-channel contribution. |
1601.06393 | Gui-Jun Ding | Cai-Chang Li, Chang-Yuan Yao, Gui-Jun Ding | Lepton Mixing Predictions from Infinite Group Series $D^{(1)}_{9n, 3n}$
with Generalized CP | 63 pages, 18 figures | null | 10.1007/JHEP05(2016)007 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We have performed a comprehensive analysis of the type D group $D^{(1)}_{9n,
3n}$ as flavor symmetry and the generalized CP symmetry. All possible residual
symmetries and their consequences for the prediction of the mixing parameters
are studied. We find that only one type of mixing pattern is able to
accommodate the measured values of the mixing angles in both "direct" and
"variant of semidirect" approaches, and four types of mixing patterns are
phenomenologically viable in the "semidirect" approach. The admissible values
of the mixing angles as well as CP violating phases are studied in detail for
each case. It is remarkable that the first two smallest $D^{(1)}_{9n,3n}$
groups with $n=1, 2$ can fits the experimental data very well. The
phenomenological predictions for neutrinoless double beta decay are discussed.
| [
{
"created": "Sun, 24 Jan 2016 15:08:52 GMT",
"version": "v1"
}
] | 2016-05-25 | [
[
"Li",
"Cai-Chang",
""
],
[
"Yao",
"Chang-Yuan",
""
],
[
"Ding",
"Gui-Jun",
""
]
] | We have performed a comprehensive analysis of the type D group $D^{(1)}_{9n, 3n}$ as flavor symmetry and the generalized CP symmetry. All possible residual symmetries and their consequences for the prediction of the mixing parameters are studied. We find that only one type of mixing pattern is able to accommodate the measured values of the mixing angles in both "direct" and "variant of semidirect" approaches, and four types of mixing patterns are phenomenologically viable in the "semidirect" approach. The admissible values of the mixing angles as well as CP violating phases are studied in detail for each case. It is remarkable that the first two smallest $D^{(1)}_{9n,3n}$ groups with $n=1, 2$ can fits the experimental data very well. The phenomenological predictions for neutrinoless double beta decay are discussed. |
hep-ph/0211044 | Dimitar Mladenov | G.A. Kozlov, T. Morii | On search for new Higgs physics in CDF at the Tevatron | 24 pages, LaTeX, 8 figures | Phys.Rev. D67 (2003) 055001 | 10.1103/PhysRevD.67.055001 | null | hep-ph | null | We discuss the Higgs boson mass sum rules in the Minimal Supersymmetric
Standard Model in order to estimate the upper limits on the masses of stop
quarks as well as the lower bounds on the masses of the scalar Higgs boson
state. The bounds on the scale of quark-lepton compositeness derived from the
CDF Collaboration (Fermilab Tevatron) data and applied to new extra gauge boson
search is taken into account. These extra gauge bosons are considered in the
framework of the extended SU(2)_h \times SU(2)_l model. In addition, we discuss
the physics of rare decays of the MSSM Higgs bosons in both CP-even and CP-odd
sectors and also some extra gauge bosons.
| [
{
"created": "Tue, 5 Nov 2002 00:31:46 GMT",
"version": "v1"
}
] | 2009-11-07 | [
[
"Kozlov",
"G. A.",
""
],
[
"Morii",
"T.",
""
]
] | We discuss the Higgs boson mass sum rules in the Minimal Supersymmetric Standard Model in order to estimate the upper limits on the masses of stop quarks as well as the lower bounds on the masses of the scalar Higgs boson state. The bounds on the scale of quark-lepton compositeness derived from the CDF Collaboration (Fermilab Tevatron) data and applied to new extra gauge boson search is taken into account. These extra gauge bosons are considered in the framework of the extended SU(2)_h \times SU(2)_l model. In addition, we discuss the physics of rare decays of the MSSM Higgs bosons in both CP-even and CP-odd sectors and also some extra gauge bosons. |
hep-ph/0209346 | Alexander Ya. Parkhomenko | Alexander Ya. Parkhomenko (Yaroslavl State University) | $B \to \rho \gamma$ Decay in the Large Energy Effective Theory | 10 pages, 3 EPS figures, talk at the 12th International Seminar
"Quarks'2002", Novgorod the Great, Russia, June 1-7, 2002 | null | null | YARU-HE-02-08 | hep-ph | null | The branching ratio for the $B \to \rho \gamma$ decay in the next-to-leading
order (NLO) in the strong coupling $\alpha_s$ and in leading power in
$\Lambda_{\rm QCD}/m_B$ is presented. The corrections are combined the
hard-vertex, hard-spectator and annihilation contributions and found to be
large. The theoretical expectation for the branching ratios, the
isospin-violating ratio and for the direct CP-asymmetry in the $B \to \rho
\gamma$ decays are presented.
| [
{
"created": "Sat, 28 Sep 2002 18:56:15 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Parkhomenko",
"Alexander Ya.",
"",
"Yaroslavl State University"
]
] | The branching ratio for the $B \to \rho \gamma$ decay in the next-to-leading order (NLO) in the strong coupling $\alpha_s$ and in leading power in $\Lambda_{\rm QCD}/m_B$ is presented. The corrections are combined the hard-vertex, hard-spectator and annihilation contributions and found to be large. The theoretical expectation for the branching ratios, the isospin-violating ratio and for the direct CP-asymmetry in the $B \to \rho \gamma$ decays are presented. |
2405.03030 | Neelima Kelkar Dr | D. F. Ram\'irez Jim\'enez, A. F. Guerrero Parra, N. G. Kelkar, M.
Nowakowski | Quantum Corrections to the Decay Law in Flight | 36 pages, 7 figures | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The deviation of the decay law from the exponential is a well known effect of
quantum mechanics. Here we analyze the relativistic survival probabilities,
$S(t,p)$, where $p$ is the momentum of the decaying particle and provide
analytical expressions for $S(t,p)$ in the exponential (E) as well as the
nonexponential (NE) regions at small and large times. Under minimal assumptions
on the spectral density function, analytical expressions for the critical times
of transition from the NE to the E at small times and the E to NE at large
times are derived. The dependence of the decay law on the relativistic Lorentz
factor, $\gamma = 1/\sqrt{1 - v^2/c^2}$, reveals several interesting features.
In the short time regime of the decay law, the critical time, $\tau_{st}$,
shows a steady increase with $\gamma$, thus implying a larger NE region for
particles decaying in flight. Comparing $S(t,p)$ with the well known time
dilation formula, $e^{-\Gamma t/\gamma}$, in the exponential region, an
expression for the critical $\gamma$ where $S(t,p)$ deviates most from
$e^{-\Gamma t/\gamma}$ is presented. This is a purely quantum correction. Under
particular conditions on the resonance parameters, there also exists a critical
$\gamma$ at large times which decides if the NE region shifts backward or
forward in time as compared to that for a particle at rest. All the above
analytical results are supported by calculations involving realistic decays of
hadrons and leptons.
| [
{
"created": "Sun, 5 May 2024 18:47:55 GMT",
"version": "v1"
}
] | 2024-05-07 | [
[
"Jiménez",
"D. F. Ramírez",
""
],
[
"Parra",
"A. F. Guerrero",
""
],
[
"Kelkar",
"N. G.",
""
],
[
"Nowakowski",
"M.",
""
]
] | The deviation of the decay law from the exponential is a well known effect of quantum mechanics. Here we analyze the relativistic survival probabilities, $S(t,p)$, where $p$ is the momentum of the decaying particle and provide analytical expressions for $S(t,p)$ in the exponential (E) as well as the nonexponential (NE) regions at small and large times. Under minimal assumptions on the spectral density function, analytical expressions for the critical times of transition from the NE to the E at small times and the E to NE at large times are derived. The dependence of the decay law on the relativistic Lorentz factor, $\gamma = 1/\sqrt{1 - v^2/c^2}$, reveals several interesting features. In the short time regime of the decay law, the critical time, $\tau_{st}$, shows a steady increase with $\gamma$, thus implying a larger NE region for particles decaying in flight. Comparing $S(t,p)$ with the well known time dilation formula, $e^{-\Gamma t/\gamma}$, in the exponential region, an expression for the critical $\gamma$ where $S(t,p)$ deviates most from $e^{-\Gamma t/\gamma}$ is presented. This is a purely quantum correction. Under particular conditions on the resonance parameters, there also exists a critical $\gamma$ at large times which decides if the NE region shifts backward or forward in time as compared to that for a particle at rest. All the above analytical results are supported by calculations involving realistic decays of hadrons and leptons. |
hep-ph/0512093 | Kentarou Mawatari | K. Hagiwara, K. Mawatari, D. Rainwater, T. Stelzer | Correlated decays of pair-produced scalar taus | revtex, 10 pages, 8 eps figures; references added, version to appear
in PRD | Phys.Rev.D73:075010,2006 | 10.1103/PhysRevD.73.075010 | KEK-TH-1057 | hep-ph | null | We study the quantum mechanical correlation between two identical neutralinos
in the decays of minimal supersymmetric standard model (MSSM) scalar tau (stau)
pair produced in e+e- annihilation. Generally, the decay products of scalar
(spinless) particles are not correlated. We show that a correlation between two
neutralinos appears near pair production threshold, due to a finite stau width
and mixing of the staus and/or neutralinos, and because the neutralinos are
Majorana. Because the correlation is significant only in a specific kinematical
configuration, it can be observed only in supersymmetric models where the
neutralino momenta can be kinematically reconstructed, such as in models with
R-parity violation.
| [
{
"created": "Thu, 8 Dec 2005 08:46:47 GMT",
"version": "v1"
},
{
"created": "Wed, 12 Apr 2006 09:44:30 GMT",
"version": "v2"
}
] | 2008-11-26 | [
[
"Hagiwara",
"K.",
""
],
[
"Mawatari",
"K.",
""
],
[
"Rainwater",
"D.",
""
],
[
"Stelzer",
"T.",
""
]
] | We study the quantum mechanical correlation between two identical neutralinos in the decays of minimal supersymmetric standard model (MSSM) scalar tau (stau) pair produced in e+e- annihilation. Generally, the decay products of scalar (spinless) particles are not correlated. We show that a correlation between two neutralinos appears near pair production threshold, due to a finite stau width and mixing of the staus and/or neutralinos, and because the neutralinos are Majorana. Because the correlation is significant only in a specific kinematical configuration, it can be observed only in supersymmetric models where the neutralino momenta can be kinematically reconstructed, such as in models with R-parity violation. |
2009.09013 | Jale Y. S\'ung\'u | J. Y. S\"ung\"u, A. T\"urkan, E. Sertbakan, E. Veli Veliev | Missing Member of the $J^{PC} = 2^{--}$ Nonet in Extreme Conditions | 4 pages | null | null | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The isoscalar member of the axial-tensor family that should take place in the
further states of the PDG is still absent. In this study, analyzes are made as
to whether one of the X states whose quantum numbers are unknown in this group,
is a candidate for the missing resonance under the assignment $ 2^3D_2 $.
Moreover, replacing the time evolution operator with the thermal average one,
we construct the modified correlator satisfying Thermal QCD sum rules approach.
We determine that the hadronic parameters of the considered nonet member are
sensitive to the increment of temperature. This knowledge can be helpful to
complete the $J^{PC} = 2^{--}$ light meson nonet and also explore the hot
medium behaviors at upcoming heavy-ion collision experiments.
| [
{
"created": "Fri, 18 Sep 2020 18:34:13 GMT",
"version": "v1"
}
] | 2020-09-22 | [
[
"Süngü",
"J. Y.",
""
],
[
"Türkan",
"A.",
""
],
[
"Sertbakan",
"E.",
""
],
[
"Veliev",
"E. Veli",
""
]
] | The isoscalar member of the axial-tensor family that should take place in the further states of the PDG is still absent. In this study, analyzes are made as to whether one of the X states whose quantum numbers are unknown in this group, is a candidate for the missing resonance under the assignment $ 2^3D_2 $. Moreover, replacing the time evolution operator with the thermal average one, we construct the modified correlator satisfying Thermal QCD sum rules approach. We determine that the hadronic parameters of the considered nonet member are sensitive to the increment of temperature. This knowledge can be helpful to complete the $J^{PC} = 2^{--}$ light meson nonet and also explore the hot medium behaviors at upcoming heavy-ion collision experiments. |
hep-ph/0503101 | Manfred Lindner | Manfred Lindner | Future Precision Neutrino Oscillation Experiments and Theoretical
Implications | Talk given at Nobel Symposium 2004: Neutrino Physics, Haga Slott,
Enkoping, Sweden, 19-24 Aug 2004 | Phys.Scripta T121:78-85,2005 | 10.1088/0031-8949/2005/T121/011 | TUM-HEP-580/05 | hep-ph | null | Future neutrino oscillation experiments will lead to precision measurements
of neutrino mass splittings and mixings. The flavour structure of the lepton
sector will therefore at some point become better known than that of the quark
sector. This article discusses the potential of future oscillation experiments
on the basis of detailed simulations with an emphasis on experiments which can
be done in about ten years. In addition, some theoretical implications for
neutrino mass models will be briefly discussed.
| [
{
"created": "Fri, 11 Mar 2005 00:17:08 GMT",
"version": "v1"
}
] | 2014-11-18 | [
[
"Lindner",
"Manfred",
""
]
] | Future neutrino oscillation experiments will lead to precision measurements of neutrino mass splittings and mixings. The flavour structure of the lepton sector will therefore at some point become better known than that of the quark sector. This article discusses the potential of future oscillation experiments on the basis of detailed simulations with an emphasis on experiments which can be done in about ten years. In addition, some theoretical implications for neutrino mass models will be briefly discussed. |
hep-ph/9312270 | null | A. Pich | Perspectives on Tau-Charm Factory Physics | 29 pages, CERN-TH.7066/93 (figures not included) | null | null | null | hep-ph | null | The Tau-Charm Factory combines the optimum conditions to perform a
high-precision investigation of the $\tau$ and $\nu_\tau$ leptons, the $c$
quark, and light-quark, glueball and hybrid spectroscopy. An overview of the
broad physics program that this facility will address is presented.
| [
{
"created": "Mon, 13 Dec 1993 18:37:21 GMT",
"version": "v1"
}
] | 2007-05-23 | [
[
"Pich",
"A.",
""
]
] | The Tau-Charm Factory combines the optimum conditions to perform a high-precision investigation of the $\tau$ and $\nu_\tau$ leptons, the $c$ quark, and light-quark, glueball and hybrid spectroscopy. An overview of the broad physics program that this facility will address is presented. |
hep-ph/9803435 | Grzegorz Wilk | G.Wilk and Z.Wlodarczyk | Inelaticity in hadron-nucleus collisions from emulsion chamber studies | LaTeX file and 5 LaTeX files with figures, 11 pages altogether.
Thoroughly rewritten and modified, one figure addded one removed. To be
published in Phys. Rev. D | Phys.Rev. D59 (1999) 014025 | 10.1103/PhysRevD.59.014025 | SINS-PVIII-1998-5 | hep-ph | null | The inelasticity of hadron-carbon nucleus collisions in the energy region
exceeding 100 TeV is estimated from the carbon-emulsion chamber data at Pamirs
to be $<K_C> = 0.65\pm 0.08$. When combined with the recently presented data on
hadron-lead nucleus collisions taken at the same energy range it results in the
$K\sim A^{0.086}$ mass number dependence of inelasticity. The evaluated partial
inelasticity for secondary ($\nu > 1$) interactions, $K_{\nu >1} \simeq 0.2$,
suggests that the second and higher interactions of the excited hadron inside
the nucleus proceed with only slight energy losses.
| [
{
"created": "Tue, 24 Mar 1998 12:27:32 GMT",
"version": "v1"
},
{
"created": "Mon, 21 Sep 1998 12:03:17 GMT",
"version": "v2"
}
] | 2009-10-31 | [
[
"Wilk",
"G.",
""
],
[
"Wlodarczyk",
"Z.",
""
]
] | The inelasticity of hadron-carbon nucleus collisions in the energy region exceeding 100 TeV is estimated from the carbon-emulsion chamber data at Pamirs to be $<K_C> = 0.65\pm 0.08$. When combined with the recently presented data on hadron-lead nucleus collisions taken at the same energy range it results in the $K\sim A^{0.086}$ mass number dependence of inelasticity. The evaluated partial inelasticity for secondary ($\nu > 1$) interactions, $K_{\nu >1} \simeq 0.2$, suggests that the second and higher interactions of the excited hadron inside the nucleus proceed with only slight energy losses. |
0712.1685 | Basarab Nicolescu | Evgenij Martynov and Basarab Nicolescu | Unified Model for Small-t and High-t Scattering at High Energies:
Predictions at RHIC and LHC | 6 pages, 2 table, 7 figures. Misprints are corrected | Eur.Phys.J.C56:57-62,2008 | 10.1140/epjc/s10052-008-0629-z | null | hep-ph | null | The urgency of predictions in large-t region at LHC stimulated us to present
a unified model of small and high t scattering at high energies. Our model is
based upon a safe theoretical ground: analyticity, unitarity, Regge behavior,
gluon exchange and saturation of bounds established in axiomatic quantum field
theory. We make precise predictions for the behavior of the differential cross
sections at high t, the evolution of the dip-shoulder structure localized in
the region of -t between 0.5 and 0.8 GeV**2 and the radical violation of the
exponential behavior of the first diffraction cone at small t.
| [
{
"created": "Tue, 11 Dec 2007 11:29:08 GMT",
"version": "v1"
},
{
"created": "Fri, 14 Dec 2007 15:31:14 GMT",
"version": "v2"
},
{
"created": "Wed, 19 Dec 2007 17:20:30 GMT",
"version": "v3"
}
] | 2016-08-25 | [
[
"Martynov",
"Evgenij",
""
],
[
"Nicolescu",
"Basarab",
""
]
] | The urgency of predictions in large-t region at LHC stimulated us to present a unified model of small and high t scattering at high energies. Our model is based upon a safe theoretical ground: analyticity, unitarity, Regge behavior, gluon exchange and saturation of bounds established in axiomatic quantum field theory. We make precise predictions for the behavior of the differential cross sections at high t, the evolution of the dip-shoulder structure localized in the region of -t between 0.5 and 0.8 GeV**2 and the radical violation of the exponential behavior of the first diffraction cone at small t. |
0706.2982 | Robert Harlander | Robert Harlander, Philipp Kant, Luminita Mihaila, Matthias Steinhauser | Dimensional Reduction applied to QCD at higher orders | 4 pages, 1 figure. Based on the talk given by R.H. at DIS 2007,
Munich, Apr 16-20, 2007 | null | null | SFB/CPP-07-32, TTP/07-13, WUB/07-05 | hep-ph | null | Recent developments in higher order calculations within the framework of
Dimensional Reduction, the preferred regularization scheme for supersymmetric
theories, are reported on. Special emphasis is put on the treatment of
evanescent couplings, the equivalence to Dimensional Regularization, and the
evaluation of $\alpha_s(M_GUT)$ from $\alpha_s(M_Z)$.
| [
{
"created": "Wed, 20 Jun 2007 13:00:51 GMT",
"version": "v1"
}
] | 2007-06-21 | [
[
"Harlander",
"Robert",
""
],
[
"Kant",
"Philipp",
""
],
[
"Mihaila",
"Luminita",
""
],
[
"Steinhauser",
"Matthias",
""
]
] | Recent developments in higher order calculations within the framework of Dimensional Reduction, the preferred regularization scheme for supersymmetric theories, are reported on. Special emphasis is put on the treatment of evanescent couplings, the equivalence to Dimensional Regularization, and the evaluation of $\alpha_s(M_GUT)$ from $\alpha_s(M_Z)$. |
hep-ph/0307164 | Pedro Fernando Simoes Costa | Pedro Costa, M. C. Ruivo and Yu. L. Kalinovsky | Anomalous decay of pion and eta at finite density | 12 pages, 4 figures included; revised version, to be published in
Phys. Lett. B | Phys.Lett. B577 (2003) 129-136; Erratum-ibid. B581 (2004) 274-275 | 10.1016/j.physletb.2003.10.020 | null | hep-ph | null | We study the anomalous decays $\pi^0, \eta \to\gamma\gamma$ in the framework
of the three--flavor Nambu--Jona-Lasinio [NJL] model, in the vacuum and in
quark matter in $\beta$ --equilibrium. It is found that the behavior of the
relevant observables essentially reflects a manifestation of the partial
restoration of chiral symmetry, in non strange and strange sectors. The
probability of such decays decreases with density, showing that anomalous
mesonic interactions are significantly affected by the medium.
| [
{
"created": "Fri, 11 Jul 2003 16:08:18 GMT",
"version": "v1"
},
{
"created": "Thu, 30 Oct 2003 21:45:53 GMT",
"version": "v2"
}
] | 2007-05-23 | [
[
"Costa",
"Pedro",
""
],
[
"Ruivo",
"M. C.",
""
],
[
"Kalinovsky",
"Yu. L.",
""
]
] | We study the anomalous decays $\pi^0, \eta \to\gamma\gamma$ in the framework of the three--flavor Nambu--Jona-Lasinio [NJL] model, in the vacuum and in quark matter in $\beta$ --equilibrium. It is found that the behavior of the relevant observables essentially reflects a manifestation of the partial restoration of chiral symmetry, in non strange and strange sectors. The probability of such decays decreases with density, showing that anomalous mesonic interactions are significantly affected by the medium. |
hep-ph/0109259 | Hai-Yang Cheng | Hai-Yang Cheng | Phenomenological Applications of QCD Factorization to Semi-inclusive B
Decays | 12 pages, talk given at International Conference on Flavor Physics,
Zhang-Jia-Jie City, Hunan, China, 31 May - 6 June, 2001 | null | 10.1142/9789812777379_0005 | null | hep-ph | null | We have systematically investigated the semi-inclusive B decays $B\to MX$,
which are manifestations of the quark decay $b \to Mq$, within a framework
inspired by QCD-improved factorization. These decays are theoretically clean
and have distinctive experimental signatures. We focus on a class of these that
do not require any form factor information and therefore may be especially
suitable for extracting information on the angles $\alpha$ and $\gamma$ of the
unitarity triangle. The strong phase coming from final-state rescattering due
to hard gluon exchange between the final states can induce large rate
asymmetries for tree-dominated color-suppressed modes
$(\pi^0,\rho^0,\omega)X_{\bar s}$. The nonfactorizable hard spectator
interactions in the 3-body decay $B\to Mq_1\bar q_2$, though phase-space
suppressed, are extremely important for the tree-dominated modes
$(\pi^0,\rho^0,\omega)X_{\bar s},~\phi X$, $J X_s,J X$ and the
penguin-dominated mode $\omega X_{s\bar s}$. Our result for ${\cal B}(B\to J
X_s)$ is in agreement with experiment. $B^0_s\to (\pi^0,\rho^0,\omega)X_{\bar
s}$, $\rho^0X_{s\bar s}$, $B^0\to(K^-X,K^{*-}X)$ and $B^-\to
(K^0X_s,K^{*0}X_s)$ are the most promising ones in searching for direct CP
violation: they have branching ratios of order $10^{-6}-10^{-4}$ and CP rate
asymmetries of order $(10-40)%$.
| [
{
"created": "Thu, 27 Sep 2001 07:50:50 GMT",
"version": "v1"
}
] | 2017-08-23 | [
[
"Cheng",
"Hai-Yang",
""
]
] | We have systematically investigated the semi-inclusive B decays $B\to MX$, which are manifestations of the quark decay $b \to Mq$, within a framework inspired by QCD-improved factorization. These decays are theoretically clean and have distinctive experimental signatures. We focus on a class of these that do not require any form factor information and therefore may be especially suitable for extracting information on the angles $\alpha$ and $\gamma$ of the unitarity triangle. The strong phase coming from final-state rescattering due to hard gluon exchange between the final states can induce large rate asymmetries for tree-dominated color-suppressed modes $(\pi^0,\rho^0,\omega)X_{\bar s}$. The nonfactorizable hard spectator interactions in the 3-body decay $B\to Mq_1\bar q_2$, though phase-space suppressed, are extremely important for the tree-dominated modes $(\pi^0,\rho^0,\omega)X_{\bar s},~\phi X$, $J X_s,J X$ and the penguin-dominated mode $\omega X_{s\bar s}$. Our result for ${\cal B}(B\to J X_s)$ is in agreement with experiment. $B^0_s\to (\pi^0,\rho^0,\omega)X_{\bar s}$, $\rho^0X_{s\bar s}$, $B^0\to(K^-X,K^{*-}X)$ and $B^-\to (K^0X_s,K^{*0}X_s)$ are the most promising ones in searching for direct CP violation: they have branching ratios of order $10^{-6}-10^{-4}$ and CP rate asymmetries of order $(10-40)%$. |
hep-ph/9808333 | Lawrence Hall | Riccardo Barbieri, Lawrence J. Hall and Alessandro Strumia | Textures for Atmospheric and Solar Neutrino Oscillations | 8 pages. Small LaTeX problem fixed in version 2 | Phys.Lett.B445:407-411,1999 | 10.1016/S0370-2693(98)01472-5 | LBNL-42164 | hep-ph | null | In theories with three light neutrinos, a complete list of five zeroth-order
textures for lepton mass matrices is found, which naturally yield: m_e =
m_mu=0, m_tau \neq 0, Delta m^2_sun = 0, together with theta_{e tau} = 0,
theta_{mu tau} approx 1. These textures provide suitable starting points for
constructing theories which account for both atmospheric and solar neutrino
fluxes. Using flavor symmetries, two schemes for such lepton masses are found,
and example constructions exhibited.
| [
{
"created": "Fri, 14 Aug 1998 18:58:44 GMT",
"version": "v1"
},
{
"created": "Mon, 17 Aug 1998 11:16:33 GMT",
"version": "v2"
}
] | 2009-10-09 | [
[
"Barbieri",
"Riccardo",
""
],
[
"Hall",
"Lawrence J.",
""
],
[
"Strumia",
"Alessandro",
""
]
] | In theories with three light neutrinos, a complete list of five zeroth-order textures for lepton mass matrices is found, which naturally yield: m_e = m_mu=0, m_tau \neq 0, Delta m^2_sun = 0, together with theta_{e tau} = 0, theta_{mu tau} approx 1. These textures provide suitable starting points for constructing theories which account for both atmospheric and solar neutrino fluxes. Using flavor symmetries, two schemes for such lepton masses are found, and example constructions exhibited. |
2007.11173 | Zhi-Qing Zhang | Zhi-Qing Zhang, Hsiang-nan Li | Next-to-Leading-logarithm threshold resummation for exclusive $B$ meson
decays | 12 pages,4 figures | null | 10.1140/epjc/s10052-021-09376-2 | null | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We extend the threshold resummation of the large logarithms $\ln x$ which
appear in factorization formulas for exclusive $B$ meson decays, $x$ being a
spectator momentum fraction, to the next-to-leading-logarithm (NLL) accuracy.
It is shown that the NLL resummation effect provides suppression in the
end-point region with $x\sim 0$ stronger than the leading-logarithm (LL) one,
and thus improves perturbative analyses of the above processes. We revisit the
$B\to K\pi$ decays under the NLL resummation, and find that it induces 20-25\%
variation of the direct CP asymmetries compared to those from the LL
resummation. Our way to avoid the Landau singularity in the inverse Mellin
transformation causes little theoretical uncertainty.
| [
{
"created": "Wed, 22 Jul 2020 02:54:20 GMT",
"version": "v1"
}
] | 2021-07-28 | [
[
"Zhang",
"Zhi-Qing",
""
],
[
"Li",
"Hsiang-nan",
""
]
] | We extend the threshold resummation of the large logarithms $\ln x$ which appear in factorization formulas for exclusive $B$ meson decays, $x$ being a spectator momentum fraction, to the next-to-leading-logarithm (NLL) accuracy. It is shown that the NLL resummation effect provides suppression in the end-point region with $x\sim 0$ stronger than the leading-logarithm (LL) one, and thus improves perturbative analyses of the above processes. We revisit the $B\to K\pi$ decays under the NLL resummation, and find that it induces 20-25\% variation of the direct CP asymmetries compared to those from the LL resummation. Our way to avoid the Landau singularity in the inverse Mellin transformation causes little theoretical uncertainty. |
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