Reduction of Cosmic Background in an X-Ray Proportional Counter through Risetime Discrimination

Abstract

The method of background reduction by risetime discrimination has been applied to a large area proportional counter for use in an x-ray astronomy observation from a sounding rocket. Analysis of data from a recent flight has shown the system to be about 90% effective in reducing the non-x-ray background observed in the space environment for the energy range 3–10 keV that persists when anticoincidence guard counters are used while at least 80% of the x-ray efficiency is retained. The system is simple, compact and does not require any critical components.