Dark Matter Detection Rates In SUGRA Models

Direct detection of Milky Way wimps are discussed within the framework of R-parity conserving SUGRA models with grand unification at MG. Two questions are discussed: what SUGRA models can account for the DAMA data if this data is confirmed, and is the full SUGRA parameter space accessible to future planned detectors. Experimental constraints of the Higgs mass bound, the b → sγ bound, relic density constraints (including all coannihilation channels), etc. are imposed. In addition, the effect of the possible muon g − 2 anomaly are examined. For mSUGRA, we find that the Higgs mass and b → sγ constraint puts a lower bound m1/2 > (300 400) GeV (i.e. mχ̃0 1 > (120 160) GeV) for tanβ <50, and thus the largest theoretical neutralino-proton cross sections still lie significantly below the DAMA 3σ lower bound. (Predictions for tan β > 50 become sensitive to the precise value of mt and mb.) If in addition one imposes the muon anomaly constraint, μ must be positive and an upper bound of m1/2 < 850 GeV for tan β < 50 is obtained. More generally, if μ > 0 and m1/2 < 1 TeV, the cross sections are > ∼ 10 pb, and hence this parameter space would be mostly accessible to planned high sensitivity detectors. For non-minimal SUGRA models, the cross sections can be considerably larger, and a simple SU(5) model with nonuniversal soft breaking in the Higgs and third generation is seen to give cross sections in the DAMA range for tanβ > ∼ 15 with mχ̃0 1 > 80 GeV, and minimum