Prospects in searches for cosmic dark matter in underground experiments

The neutralino is considered as a particle of dark galactic matter. Some general problems encountered in direct searches for dark matter by detecting events of elastic neutralino-nucleus scattering are discussed. On the basis of the most general ideas of nuclear and nucleon structures, constraints that direct detection of dark matter may impose on the parameter space of supersymmetric models are analyzed. A criterion of sensitivity to various groups of parameters that characterize supersymmetric models is proposed. According to this criterion, all detectors of dark matter are divided into three categories. On the basis of the minimal supersymmetric standard model (MSSM), the event rate for neutralino-nucleus scattering is calculated for various isotopes that are of interest for developing dark-matter detectors. In this calculation, accelerator and cosmological constraints on the MSSM parameter space are taken into account. The effect of nuclear spin on elastic neutralino-nucleus scattering is studied. It is found that the role of spin-dependent interaction in neutralino-nucleus scattering is of minor importance for nuclei with mass numbers that are not less than 50.