Update on the direct detection of supersymmetric dark matter

Abstract

We compare updated predictions for the elastic scattering of supersymmetric neutralino dark matter with the improved experimental upper limit recently published by Cryogenic Dark Matter Search (CDMS) II. We take into account the possibility that the $\pi$-nucleon $\Sigma$ term may be somewhat larger than was previously considered plausible, as may be supported by the masses of exotic baryons reported recently. We also incorporate the new central value of $m_t$, which affects indirectly constraints on the supersymmetric parameter space, for example, via calculations of the relic density. Even if a large value of $\Sigma$ is assumed, the CDMS II data currently exclude only small parts of the parameter space in the constrained minimal standard model (CMSSM) with universal soft supersymmetry-breaking Higgs, squark, and slepton masses. None of the previously proposed CMSSM benchmark scenarios is excluded for any value of $\Sigma$, and the CDMS II data do not impinge on the domains of the CMSSM parameter space favored at the 90% confidence level in a recent likelihood analysis. However, some models with nonuniversal Higgs, squark, and slepton masses and neutralino masses $\lesssim 700\mathrm{GeV}$ are excluded by the CDMS II data.