A fluorescent gated gas scintillation proportional counter for high energy X-ray spectroscopy

Abstract Results are presented on a background rejection technique suitable for xenon gas filled detectors measuring X-rays above 35 keV. The technique involves the separate detection of both the xenon K shell fluorescent photon, emitted in most interactions involving the photoabsorption of high energy X-rays above 34.5 keV, and the residual event from the initial photoabsorption. This technique when applied to gas scintillation proportional counters filled with 1 atm xenon yields a background rejection efficiency of ∼97.3% and an energy resolution of ∼2.5% at 60 keV.