Operation results are presented of a UV-sensitive gaseous photomultiplier(GPM) coupled through a MgF2 window to a liquid-xenon scintillator. Itconsisted of a reflective CsI photocathode deposited on top of a THick GaseousElectron Multiplier (THGEM); further multiplication stages were either a secondTHGEM or a Parallel Ionization Multiplier (PIM) followed by a MICROMEsh GAseousStructure (MICROMEGAS). The GPM operated in gas-flow mode with non-condensablegas mixtures. Gains of 10^4 were measured with a CsI-coated double-THGEMdetector in Ne/CH4 (95:5), Ne/CF4 (95:5) and Ne/CH4/CF4 (90:5:5), with softX-rays at 173 K. Scintillation signals induced by alpha particles in liquidxenon were measured here for the first time with a double-THGEM GPM in He/CH4(92.5:7.5) and a triple-structure THGEM/PIM/MICROMEGAS GPM in Ne/CH4 (90:10)with a fast-current preamplifier.
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