Ref HAL: hal-00344952_v1
Ref Arxiv: 0812.0788
DOI: 10.1103/PhysRevD.80.063509
WoS: 000270385200028
Ref. & Cit.: NASA ADS
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51 Citations
Résumé:

Supersymmetric extensions of the standard model of particle physics assumingthe gravitino to be the lightest supersymmetric particle (LSP), and with thenext-to-LSP decaying to the gravitino during Big Bang nucleosynthesis, areanalyzed. Particular emphasis is laid on their potential to solve the "Li7problem", an apparent factor 2-4 overproduction of Li7 in standard Big Bangnucleosynthesis (BBN), their production of cosmologically important amounts ofLi6, as well as the resulting minimum gravitino dark matter densities in thesemodels. The study includes several improvements compared to prior studies.Heavy gravitinos in the constrained minimal supersymmetric standard model(CMMSM) are reanalyzed, whereas light gravitinos in gauge-mediatedsupersymmetry breaking scenarios (GMSB) are studied for the first time. It isconfirmed that decays of NLSP staus to heavy gravitinos, while producing allthe dark matter, may at the same time resolve the Li7 problem. For NLSP decaytimes ~ 1000 sec, such scenarios also lead to cosmologically important Li6 (andpossibly Be9) abundances. However, as such scenarios require heavy > 1 TeVstaus they are likely not testable at the LHC. It is found that decays of NLSPstaus to light gravitinos may lead to significant Li6 (and Be9) abundances,whereas NLSP neutralinos decaying into light gravitinos may solve the Li7problem. Though both scenarios are testable at the LHC they may not lead to theproduction of the bulk of the dark matter. A section of the paper outlinesparticle properties required to significantly reduce the Li7 abundance, and/orenhance the Li6 (and possibly Be9) abundances, by the decay of an arbitraryrelic particle.

Commentaires: 13 pages (revtex), 9 figures. publié, 10.1103/PhysRevD.80.063509

Ref HAL: hal-00546812_v1
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Résumé:

We address the question of dark matter in the context of gauge mediated supersymmetry breaking models. In contrast with mSUGRA scenarios, the messenger of the susy breaking to the visible sector can play an important role allowing a relic gravitino in the similar to keV to 10 MeV mass range to account for the cold dark matter in the Universe.

Ref HAL: in2p3-00252151_v1
Ref Arxiv: 0712.3151
DOI: 10.1103/PhysRevD.77.055014
WoS: 000254544200071
Ref. & Cit.: NASA ADS
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6 Citations
Résumé:

We study the complementarity between the indirect detection of dark matter with gamma-rays in H.E.S.S. and the supersymmetry searches with ATLAS at the Large Hadron Collider in the Focus Point region within the mSUGRA framework. The sensitivity of the central telescope of the H.E.S.S. II experiment with an energy threshold of ~ 20 GeV is investigated. We show that the detection of gamma-ray fluxes of O(10^-12) cm-2s-1 with H.E.S.S. II covers a substantial part of the Focus Point region which may be more difficult for LHC experiments. Despite the presence of multi-TeV scalars, we show that LHC will be sensitive to a complementary part of this region through three body NLSP leptonic decays. This interesting complementarity between H.E.S.S. II and LHC searches is further highlighted in terms of the gluino mass and the two lightest neutralino mass difference.

Commentaires: 11 pages, 6 figures, accepted for publication in Phys. Rev. D on February 7, 2008 (slight modifications: references updated and text improved)

Ref HAL: in2p3-00252149_v1
Ref Arxiv: 0710.5121
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
Résumé:

We address the question of gravitino dark matter in the context of gauge mediated supersymmetry breaking models. A special emphasis is put on the role played by the MSSM singlet messenger in the case of SO(10) grand unification.

Commentaires: 4 pages, LaTeX, 2 eps figures

Ref HAL: in2p3-00254733_v1
Ref Arxiv: 0712.3465
DOI: 10.1063/1.2823771
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
Résumé:

We address the question of gravitino dark matter in the context of gauge mediated supersymmetry breaking models.

Commentaires: paru dans les compte-rendus de PASCOS07

Ref HAL: in2p3-00141614_v1
Ref Arxiv: hep-ph/0612331
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
Résumé:

We address the question of dark matter in the context of gauge mediated supersymmetry breaking models. In contrast with mSUGRA scenarios, the messenger of the susy breaking to the visible sector can play an important role allowing a relic gravitino in the $\sim {keV}$ to $10 {MeV}$ mass range to account for the cold dark matter in the Universe.

Ref HAL: in2p3-00025241_v1
Ref Arxiv: hep-ph/0511344
DOI: 10.1140/epjc/s2005-02460-1
WoS: 000241559400003
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
236 Citations
Résumé:

High-precision analyses of supersymmetry parameters aim at reconstructing the fundamental supersymmetric theory and its breaking mechanism. A well defined theoretical framework is needed when higher-order corrections are included. We propose such a scheme, Supersymmetry Parameter Analysis SPA, based on a consistent set of conventions and input parameters. A repository for computer programs is provided which connect parameters in different schemes and relate the Lagrangian parameters to physical observables at LHC and high energy e+e- linear collider experiments, i.e., masses, mixings, decay widths and production cross sections for supersymmetric particles. In addition, programs for calculating high-precision low energy observables, the density of cold dark matter (CDM) in the universe as well as the cross sections for CDM search experiments are included. The SPA scheme still requires extended efforts on both the theoretical and experimental side before data can be evaluated in the future at the level of the desired precision. We take here an initial step of testing the SPA scheme by applying the techniques involved to a specific supersymmetry reference point.

Commentaires: 17pp; references corrected