  A new method of searching for dark matter in the form of weakly interacting
massive particles (WIMP) has been developed with the direct detection of the
low energy nuclear recoils observed in a massive target (ultimately many tons)
of ultra pure Liquid Argon at 87 K. A high selectivity for Argon recoils is
achieved by the simultaneous observation of both the VUV scintillation
luminescence and of the electron signal surviving columnar recombination,
extracted through the liquid-gas boundary by an electric field. First physics
results from this method are reported, based on a small 2.3 litre test chamber
filled with natural Argon and an accumulated fiducial exposure of about 100 kg
x day, supporting the future validity of this method with isotopically purified
40Ar and for a much larger unit presently under construction with
correspondingly increased sensitivities.
