THE PERFORMANCE OF A COMPACT GAS PROPORTIONAL SCINTILLATION-COUNTER FOR HARD X-RAY SPECTROMETRY

We report the performance of a compact, room-temperature, xenon gas pr oportional scintillation counter (GPSC) for detecting 20- to 60-keV X rays. The GPSC achieves an energy resolution and detection efficiency that are acceptable for energy-dispersive X-ray fluorescence (EDXRF) a nalysis of heavy elements. The 10-cm diameter by 20-cm long overall di mensions of the detector include a 25-mm diameter entrance window, a 5 -cm diameter photomultiplier assembly, a 4-cm absorption region, and a 1-cm scintillation region. The energy resolution of a 1-cm diameter, collimated X-ray beam is between 4 and 5% in the energy range between 20 and 60 keV. The overall performance of this detector for EDXRF anal ysis is discussed in terms of energy resolution, linearity, detection efficiency and counting rates as derived from the K and L characterist ic radiation of heavy elements and is compared with other room-tempera ture detectors.