ELECTROLUMINESCENCE YIELD FOR LAMBDA-GREATER-THAN-165 NM IN NEON-XENON MIXTURES - EXPERIMENTAL RESULTS

The electroluminescence yield for lambda>165 nm in neon-xenon mixtures at a total pressure of about 800 torr, is studied as a function of th e reduced electric field in a uniform-field gas proportional scintilla tion counter. Scintillation and ionization thresholds were experimenta lly observed to decrease monotonically as a function of xenon concentr ation, from approximately 1 and 6 Vcm(-1) torr(-1) for 100% xenon, to 0.5 and 3.8 Vcm(-1) torr(-1) for 20% xenon, to 0.4 and 2.8 Vcm(-1) tor r(-1) for 10% xenon and to 0.3 and 2.2 Vcm(-1) torr(-1) for 5% xenon. Detector energy resolutions for the aluminum K-alpha line at 1.487 keV were determined to be 15% for 20% xenon, 19% for 10% xenon and 22% fo r 5% xenon mixtures.