A Pulsed Radiation Energy Spectrometer Using Ferroelectrics

Abstract

The differential energy spectrum of a flash x-ray source or other pulsed radiation sources may be measured using the ferroelectric radiation detector. The detector, consisting of the poled ceramic lead zirconate titanate, exhibits a pulse charge output which is proportional to the absorbed dose. The spectrorneter system itself employs a filtration technique where a set of energy-selective metal filters is positioned in front of a corresponding set of ferroelectric detectors, and the radiation induced charge output of each detector is measured. From this data the spectrum of the pulsed radiation source is deduced by the use of a numerical unfolding technique. Experimentally, the concept of the ferroelectric spectrometer system was verified by measuring the spectrum of a 0.6 MVP flash x-ray machine. Since the ferroelectric detector exhibits a dynamic response to the incident radiation pulse, the same spectrometer concept is used to measure the spectrum as a function of time. The time-dependent character of tnle flash x-ray machine spectrum was detected experimentally and tne results showed that the energy spectrum is harder during the first portion of the pulse.