Dark matter protohalos in a nine parameter MSSM and implications for direct and indirect detection

We study how the kinetic decoupling of dark matter within a minimal supersymmetric extension of the standard model, by adopting nine independent parameters (MSSM-9), could improve our knowledge of the properties of the dark matter protohalos. We show that the most probable neutralino mass regions, which satisfy the relic density and the Higgs mass constraints, are those with the lightest supersymmetric neutralino mass around 1 TeV and 3 TeV, corresponding to Higgsino-like and winolike neutralino, respectively. The kinetic decoupling temperature in the MSSM-9 scenario leads to a most probable protohalo mass in a range of M-ph similar to 10(-12)-10(-7)M(circle dot). The part of the region closer to similar to 2 TeV gives also important contributions from the neutralino-stau coannihilation, reducing the effective annihilation rate in the early Universe. We also study how the size of the smallest dark matter substructures correlates to experimental signatures, such as the spin-dependent and spin-independent scattering cross sections, relevant for direct detection of dark matter. Improvements on the spin-independent sensitivity might reduce the most probable range of the protohalo mass between similar to 10(-9)M(circle dot) and similar to 10(-7)M(circle dot),while the expected spin-dependent sensitivity provides weaker constraints. We show how the boost of the luminosity due to dark matter annihilation increases, depending on the protohalo mass. In the Higgsino case, the protohalo mass is lower than the canonical value often used in the literature (similar to 10(-6)M(circle dot)), while hsvi does not deviate from <sigma nu > similar to 10(-26) cm(3) s(-1); there is no significant enhancement of the luminosity. On the contrary, in the wino case, the protohalo mass is even lighter, and <sigma nu > is two orders of magnitude larger; as its consequence, we see a substantial enhancement of the luminosity.