Exploration of elastic scattering rates for supersymmetric dark matter

We explore the possible cross sections for the elastic scattering ofneutralinos chi on nucleons p,n in the minimal supersymmetric extension of thestandard model (MSSM). Universality of the soft supersymmetry-breaking scalarmasses for the Higgs multiplets is not assumed, but the MSSM parameters arenevertheless required to lead consistently to an electroweak vacuum. We exploresystematically the region of MSSM parameter space where LEP and otheraccelerator constraints are respected, and the relic neutralino density lies inthe range 0.1 < Omega_chi h^2 < 0.3 preferred by cosmology. We also discussmodels with Omega_chi h^2 < 0.1, in which case we scale the density ofsupersymmetric dark matter in our galactic halo by Omega_chi h^2 / 0.1,allowing for the possible existence of some complementary form of cold darkmatter. We find values of the cross sections that are considerably lower thanthe present experimental sensitivities. At low neutralino masses, m_chi < 100GeV, the cross sections may be somewhat higher than in the constrained MSSMwith universal soft Higgs masses, though they are generally lower. In the caseof large m_chi, the cross sections we find may be considerably larger than inthe constrained model, but still well below the present experimentalsensitivity.Comment: 25 pages LaTeX, 7 eps figure