3,237 research outputs found
Comparison of SUSY spectrum calculations and impact on the relic density constraints from WMAP
We compare results of four public supersymmetric (SUSY) spectrum codes,
Isajet, Softsusy, Spheno and Suspect to estimate the present-day uncertainty in
the calculation of the relic density of dark matter in mSUGRA models. We find
that even for mass differences of about 1% the spread in the obtained relic
densities can be 10%. In difficult regions of the parameter space, such as
large tan(beta) or large m_0, discrepancies in the relic density are much
larger. We also find important differences in the stau co-annihilation region.
We show the impact of these uncertainties on the bounds from WMAP for several
scenarios, concentrating on the regions of parameter space most relevant for
collider phenomenology. We also discuss the case of non-zero A_0 and the stop
co-annihilation region. Moreover, we present a web application for the online
comparison of the spectrum codes.Comment: 26 pages, 6 figures, 10 tables; version to appear in PR
On Prospects for Exploration of Supersymmetry in Double Beta Decay Experiments
We analyze constraints on the parameters of the R-parity violating
supersymmetry which can be extracted from non-observation of the neutrinoless
nuclear double beta decay () at a given half-life lower bound.
Our analysis covers a large class of phenomenologically viable R-parity
violating SUSY models. We introduce special characteristics: the SUSY
sensitivity of a decaying isotope and the SUSY reach of a
experiment. The former provides a physical criterion for a
selection of the most promising isotopes for SUSY searches and the latter gives
a measure of success for a experiment in exploring the
R-parity violating SUSY parameter space. On this basis we discuss prospects for
exploration of supersymmetry in various experiments.Comment: 11 pages, 5 Postscript figures. Modified and updated version is
printed also in Proc. of NANP97 (JINR, Dubna, July 7--11, 1997): Phys. Atom
Nucl, 1998, 61, vol. 6, p.1092--109
One needs positive signatures for detection of Dark Matter
One believes there is huge amount of Dark Matter particles in our Galaxy
which manifest themselves only gravitationally. There is a big challenge to
prove their existence in a laboratory experiment. To this end it is not
sufficient to fight only for the best exclusion curve, one has to see an annual
recoil spectrum modulation --- the only available positive direct dark matter
detection signature. A necessity to measure the recoil spectra is stressed.Comment: 16 pages, 1 figure. arXiv admin note: substantial Appendix text
overlap with arXiv:0806.3917; missed acknowledge is added onl
Constraints on the intrinsic charm content of the proton from recent ATLAS data
Constraints on the intrinsic charm probability \wccm = P_{{\mathrm{c}\bar
\mathrm{c}} / \mathrm{p}} in the proton are obtained for the first time from
LHC measurements. The ATLAS Collaboration data for the production of prompt
photons, accompanied by a charm-quark jet in pp collisions at
TeV, are used. The upper limit \mbox{\wccm < 1.93~\%} is obtained at the
68~\% confidence level. This constraint is primarily determined from the
theoretical scale and systematical experimental uncertainties. Suggestions for
reducing these uncertainties are discussed. The implications of intrinsic heavy
quarks in the proton for future studies at the LHC are also discussed.Comment: 6 pages, 4 figure
Higgs Bosons and the Indirect Search for WIMPs
We investigated the contribution of the MSSM Higgs bosons produced in the
neutralino annihilation in the Earth and Sun to the total WIMPs detection
signals. We found that this contribution is very important and results in a
lower bound for the muon flux from the Sun of 10^{-7} - 10^{-8} m^{-2} yr^{-1}
for neutralinos heavier than 200 GeV. We noticed that due to the SUSY charged
Higgs bosons one can expect an energetic tau neutrino flux from the Sun at a
level of 10^2 m^{-2} yr^{-1}.Comment: 10 pages, 4 figures. Talk given at Dark2000, Heidelberg, Germany,
10-15 July, 200
Neutrino Fluxes from CMSSM LSP Annihilations in the Sun
We evaluate the neutrino fluxes to be expected from neutralino LSP
annihilations inside the Sun, within the minimal supersymmetric extension of
the Standard Model with supersymmetry-breaking scalar and gaugino masses
constrained to be universal at the GUT scale (the CMSSM). We find that there
are large regions of typical CMSSM planes where the LSP
density inside the Sun is not in equilibrium, so that the annihilation rate may
be far below the capture rate. We show that neutrino fluxes are dependent on
the solar model at the 20% level, and adopt the AGSS09 model of Serenelli et
al. for our detailed studies. We find that there are large regions of the CMSSM
planes where the capture rate is not dominated by
spin-dependent LSP-proton scattering, e.g., at large along the CMSSM
coannihilation strip. We calculate neutrino fluxes above various threshold
energies for points along the coannihilation/rapid-annihilation and focus-point
strips where the CMSSM yields the correct cosmological relic density for
tan(beta) = 10 and 55 for > 0, exploring their sensitivities to
uncertainties in the spin-dependent and -independent scattering matrix
elements. We also present detailed neutrino spectra for four benchmark models
that illustrate generic possibilities within the CMSSM. Scanning the
cosmologically-favored parts of the parameter space of the CMSSM, we find that
the IceCube/DeepCore detector can probe at best only parts of this parameter
space, notably the focus-point region and possibly also at the low-mass tip of
the coannihilation strip.Comment: 32 pages, 13 figures. v2: updated/expanded discussion of
IceCube/DeepCor
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