Lahanas Athanasios

(*University of ATHENS)*

Neutralino dark matter in view of recent cosmological data

I will discuss the neutralino relic density in an accelerating Universe with non vanishing cosmological constant. Recent astrophysical observations provide us with very accurate values for the cosmological parameters that have direct implications for particle physics. In the framework of MSSM these can put severe constraints on the supersymmetry breaking parameters, namely the values of the soft masses m_0 and M_{1/2}, and hence on sparticle spectrum. These constraints can be avoided if we move to the large tan(beta) region or if the parameters are so chosen that the LSP is almost degenerate in mass with the lightest of staus.