SUPERSYMMETRIC DARK MATTER: MSSM and SUGRA schemes in the light of a possible annual modulation effect in WIMP direct search

Recently the DAMA/NaI Collaboration reported further indication of a possible modulation effect in WIMP direct detection. In this note we discuss the relevance of this result for supersymmetric theories where the neutralino is the dark matter candidate. We specifically consider the Minimal Supersymmetric extension of the Standard Model (MSSM) and Supergravity-inspired schemes, with possible deviations of the unification conditions at the GUT scale in the Higgs sector. The main results of our analysis show that the annual modulation data are widely compatible with an interpretation in terms of a relic neutralino as the major component of dark matter in the Universe. We also discuss the implications for searches of supersymmetry at accelerators and for indirect searches of neutralino dark matter