Proportional quartz-glass counter for detecting external X-rays

The described counter incorporates a cathode of pyrolytic graphite and a similar to 0.15-mm-thick entrance window with similar to 5-cm(2) area. The counter service life, being defined by a change of 1% in the gas-amplification coefficient M, exceeds 1.1 x 10(-3) C/cm (i.e., 1.5 x 10(10) pulses/cm for 22.2-keV X-rays at M = 447). In the -50 to +120 degrees C temperature range, the value of M and energy resolution are virtually constant. The resolution of the 22.2-keV X-ray line is 7.3% for a 100-s(-1) count rate.