Room temperature CdZnTe X- and #gamma#-ray detectors for nuclear physics applications

Gamma-ray spectroscopy is undoubtedly the most effective tool for understanding the structure of the nucleus. In common with many other problems however, there is more information available that can be readily measured by standard experimental facilities. Therefore, this thesis investigates the potential for the use of a new detector material, CdZnTe, in nuclear physics applications. To evaluate the requirements of detection systems for nuclear physics applications, a #gamma#-ray spectroscopy experiment was performed to investigate neutron alignments in "1"0"0Mo, "1"0"4Ru and "1"0"8Pd using deep-inelastic reactions. This showed that a detector capable of detecting low energy (< 100 keV) X-rays without compromising #gamma#-ray detection efficiency could have, significant benefit. A room temperature CdZnTe semiconductor detector could reasonably form part of a standard escape suppressed spectrometer. However, there is a substantially higher leakage current associated with room temperature semiconductor devices than standard cryogenically cooled semiconductor detectors. CdZnTe suffers from significant charge trapping, and therefore the rise time of the radiation induced pulses forms an important part of the signal analysis from such detectors. These two problems have implications on the design of preamplifier systems for CdZnTe detectors. For this reason, this thesis describes the design of optimised electronic systems for use with room-temperature operated CdZnTe detectors. Here, the focus is on the preamplifier design, and on practical ways of analysing noise performance of the preamplifier. A new preamplifier configuration with digital output has been developed, and a detailed signal-to-noise analysis performed. Such a circuit facilitates simultaneous measurement of both energy and pulse shape information. (author)SIGLEAvailable from British Library Document Supply Centre-DSC:DXN032070 / BLDSC - British Library Document Supply CentreGBUnited Kingdo