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arXiv · 0906.4696

BMSSM Implications for Cosmology

Abstract

The addition of non-renormalizable terms involving the Higgs fields to the MSSM (BMSSM) ameliorates the little hierarchy problem of the MSSM. We analyze in detail the two main cosmological issues affected by the BMSSM: dark matter and baryogenesis. The regions for which the relic abundance of the LSP is consistent with WMAP and collider constraints are identified, showing that the bulk region and other previously excluded regions are now permitted. Requiring vacuum stability limits the allowed regions. Based on a two-loop finite temperature effective potential analysis, we show that the electroweak phase transition can be sufficiently first order in regions that for the MSSM are incompatible with the LEP Higgs mass bound, including parameter values of \tanβ\lsim 5, m_{\tilde{t}_{1}} > m_t, m_Q << TeV.

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Nicolas Bernal, Kfir Blum, Marta Losada, Yosef Nir. 2009-07-15. BMSSM Implications for Cosmology. https://doi.org/10.1088/1126-6708/2009/08/053

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