Discrete analog electronics for high-resistivity silicon detectors used for X-ray and gamma-ray spectroscopy in whole-body monitoring

The work is aimed at developing an in vivo spectroscopy system for radiation protection monitoring to improve the lung detection of Pu-239 and Am-241. Silicon components have been investigated for high-resolution spectroscopy (2 keV) at room temperature to measure 59.5 keV Am-241 gamma rays. The requirements and constraints of such device are reviewed. The work is focused on analog electronics and detector development. As a first step, multi-channel electronic circuits based on a low-noise charge-sensitive preamplifier have been built by carrying the FETs and feedback capacitances close to the strips. The performance is presented for a large-area strip silicon detector (3 x 3 cm(2)). Measurements are compared with simulations and discussed with respect to application requirements.