The Long-Term Stability of a Fused-Silica Proportional Counter

Abstract

The long-term stability of the counting and spectrometric characteristics of a fused silica proportional counter has been investigated to assess its applicability to search for an admixture of sterile neutrinos. The results of continuous measurements of the K-peak position in the spectrum of deposited energies from decay of ³⁷Ar traces in a counter filled with CO₂ are presented. It is shown that the gas amplification remained stable within 0.1% during 1 month of continuous measurements at an initial isotope activity of approximately 100 Bq. This estimate of the stability of a fused silica counter is 5 times better than the values published earlier.