  The recent WMAP data have confirmed that exotic dark matter together with the
vacuum energy (cosmological constant) dominate in the flat Universe. The nature
of the dark matter constituents cannot be determined till they are directly
detected. Recent developments in particle physics provide a number of
candidates as constituents of dark matter, called Weakly Interacting Massive
Particles (WIMPs). Since these interact weakly and are of low energy they
cannot excite the target and can only be detected via measuring the recoiling
nucleus. For all WIMPs, including the most popular candidate, the lightest
supersymmetric particle (LSP), the relevant cross sections arise out of the
following mechanisms: i) The coherent mode, due to the scalar interaction. ii)
The charge coherent mode, with only proton contribution, as in the recent case
of secluded dark matter scenario and iii) The spin contribution arising from
the axial current. In this paper we will focus on the spin contribution, which
maybe important, especially for light targets.
