“…Members of the same Coimbra, Portugal group also studied various argon-xenon Penning gas mixtures in gridded microstrip gas detectors. 60 A 95% Ar-5% Xe gas mixture was shown to provide a tenfold improvement in charge multiplication gains and an improved energy resolution of 12.5% at 5.9 keV over a pure xenon gas fill. A slight improvement in energy resolution to 12.3% was achieved with the addition of 9.5% methane quench gas.…”