Evaluation of Front-end Electronics for Unattended Safeguards Instruments

The International Atomic Energy Agency is expanding the use of unattended, remotely monitored nondestructive assay systems. Often, the radiation sensors in these systems are located in harsh environments with limited accessibility (e.g. reactor vaults, hot cells), making it difficult and costly to calibrate, repair and replace nuclear electronics components co-located with the detectors. Improved Front-end Electronics for Unattended Measurement (FEUM) are being investigated, with improvements in reliability, standardization and user accessibility as the primary objectives. Experiments have supported a preliminary characterization of selected commercially available charge-sensitive and current-sensitive preamplifiers. The results from these experiments have informed technical specifications, both functional requirements and performance targets, for the procurement of front-end electronics specifically engineered to the needs of unattended instruments for nuclear fuel cycle safeguards.