Performance of a digital CdTe X-ray spectrometer in low and high counting rate environment

Abstract

The high performances of CdTe detectors for X-ray and gamma ray spectroscopy are already well known. Among the traditional semiconductor spectrometers, CdTe detectors show high detection efficiency and good room temperature performance and are well suited for the development of compact detection systems. In this work, we investigated the performance of a CdTe detector coupled with a custom digital pulse processing (DPP) system for X-ray spectroscopy. The DPP method, implemented on a PC platform, performs a pile-up inspection and a pulse height analysis of the preamplifier output pulses, digitized by a 14-bit, 100MHz ADC. The spectroscopic results point out the excellent performance of the digital spectrometer both at low (150cps) and at high photon counting rate (up to 370kcps), confirming the high potentialities of CdTe detectors coupled with DPP systems. The detector and the DPP system were developed by our collaboration as a spectrometer prototype for direct measurement of diagnostic X-ray spectra in the 1–40keV energy range.