Search for WIMPs dark matter by means of thin NaI(Tl) scintillator

The segmented detector system made of inorganic crystal is applied to serach for WIMPs dark matter. The NaI(Tl) crystal has great advantages to search for WIMPs dark matter;. \begin{enumerate} \item 100\% of natural abundance of odd $A$ nuclei ($^{23}$Na and $^{127}$I). \item $^{127}$I has a low energy excited state at 57.6keV which is excited by spin-dependent interaction. \end{enumerate} The prototype detector of thin NaI(Tl) was tested. The energy resolution and the low energy threshold will be reported. The future prospect of WIMPs dark matter search by various detector will be discussed.