Measurement of high x-ray doses from PF1000 plasma focus using Si p-i-n detectors

Abstract

A thick silicion p-i-n detector of special design has been applied for measurement of medium-hardness x-rays (10÷30 keV) from the 1MJPF1000 Plasma Focus Facility in Warsaw. The detector operates in an integrating mode that gives a possibility of dealing with high doses of radiation. When exposed to multiple-pulse emissions from plasma focus, the integrating detection system produces a stair-like output signal. The real time-resolved shape of the x-ray emission can be restored by applying numerical differentiation. The system is complementary to another soft x-ray diagnostics applied at the PF1000, which operates in soft energy range about 1 keV, in which attenuation of x-ray flux was accomplished by the use of a pinhole. In the paper the detection system is described in detail and some typical examples of measurement results which are correlated to specific patterns of the plasma focus discharge are shown. Different geometrical configurations of imaging an x-ray source onto detectors are considered and futher possible improvements of detection systems are disussed.