BOLOMETRIC DIRECT DARK-MATTER SEARCH AT THE UNIVERSITY-OF-TOKYO

A direct dark matter search experiment is now under preparation at the University of Tokyo. An array of LiF bolometers with a total mass of roughly one kilogram is to be used aiming at a direct detection of spi n-dependently interacting supersymmetric neutralinos. A dedicated low- radioactivity dilution refrigerator for the bolometer has been constru cted along with a small on-line helium requefier to help the detector operation in the underground laboratory where liquid helium supply is not always available. A long term test operation of a bolometer at the University of Tokyo proved the stability of the detector for more tha n 45 days. The detector will be installed in the Nokogiri-yama undergr ound laboratory of the Institute for Cosmic Ray Research of the Univer sity of Tokyo. The laboratory is 200 m w.e. deep and located about 60 km to the south of Tokyo.