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تسجيل مستخدم جديدLight stops in the MSSM parameter space
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We consider the regions of the MSSM parameter space where the top squarks become light and even may be the LSP. This happens when the triple scalar coupling A becomes very big compared to m_0. We show that in this case the requirement that the LSP is neutral imposes noticeable constraint on the parameter space excluding low m_0 and m_{1/2} similar to constraint from the Higgs mass limit. In some cases these constraints overlap. This picture takes place in a wide region of tanbeta. In a narrow band close to the border line the stops are long-lived particles and decay into quarks and neutralino (chargino). The cross-section of their production at LHC via gluon fusion mechanism in this region may reach a few pb.
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The ATLAS and CMS experiments have recently announced the discovery of a Higgs-like resonance with mass close to 125 GeV. Overall, the data is consistent with a Standard Model (SM)-like Higgs boson. Such a particle may arise in the minimal supersymme
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We examine the neutralino relic density in the presence of a light top squark, such as the one required for the realization of the electroweak baryogenesis mechanism, within the minimal supersymmetric standard model. We show that there are three clea
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