The stability of high-pressure xenon gamma-ray specrometers has been measured at Mirmar Sensor. Stability was measured by tracking the 137Cs peak of the entire spectroscopy system including detector, preamplifier, amplifier, and multichannle analyzer over 6 days in a laboratory setting. Overall system gain drift is about 0.016%. Resolution drifts are about 0.15%. The overall energy resolution is between 1.7 and 1.8% at 662 keV.
Albert Beyerle, Albert Beyerle,
"Stability of high-pressure xenon gamma-ray spectrometers", Proc. SPIE 5922, Hard X-Ray and Gamma-Ray Detector Physics VII, 59220C (16 September 2005); doi: 10.1117/12.622628; https://doi.org/10.1117/12.622628