  The main characteristics of a new concept of spherical gaseous detectors,
with some details on its operation are first given. The very low energy
threshold of such detector has led to investigations of its potential
performance for dark matter particle searches, in particular low mass WIMP's :
original methods for energy and fiducial volume calibration and background
rejection are described and preliminary results obtained with a low
radioactivity prototype operated in Laboratoire Souterrain de Modane ("Frejus"
lab) are presented. Typical expected sensitivities in cross section for low
mass WIMP's are also shown, and other applications briefly discussed.
