Pulsed soft x-ray response of InP:Fe photoconductors

Abstract

We report measurements of the energy-dependent pulse response of InP:Fe photoconductors to soft x rays in the energy range 200 eV–3 keV. The experiments were performed with x-ray pulses from the Stanford Positron Electron Asymmetric Ring storage ring at the Stanford Synchrotron Radiation Laboratory. The detector had an optical impulse response of 180 ps (full width at half-maximum) and an active area of 1×1 mm. An array of filters (carbon, magnesium, and beryllium) was used to unfold the energy response of the detector to the soft x rays. Direct measurements of the time structure of the ring bunches were limited by the bandwidth of the real time recording system (400 MHz), but inidividual ring pulses were easily recorded with a detector pulse amplitude of 65 mV for the unfiltered beam. The detector response was constant over the energy range examined at 2.7×10−3 A/W.