The Yale-Weizmann collaboration aims to develop a low-radioactivity(low-background) cryogenic noble liquid detector for Dark-Matter (DM) search inmeasurements to be performed deep underground as for example carried out by theXENON collaboration. A major issue is the background induced by naturalradioactivity of present-detector components including the Photo MultiplierTubes (PMT) made from glass with large U-Th content. We propose to use advancedThick Gaseous Electron Multipliers (THGEM) recently developed at the WeizmannInstitute of Science (WIS). These "hole-multipliers" will measure in atwo-phase (liquid/gas) Xe detector electrons extracted into the gas phase fromboth ionization in the liquid as well as scintillation-induced photoelectronsfrom a CsI photocathode immersed in LXe. We report on initial tests (in gas) ofTHGEM made out of Cirlex (Kapton) which is well known to have low Ra-Th contentinstead of the usual G10 material with high Ra-Th content.
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