24.1.3.1.1 – Frisch Grid CZT Spectrometer

During FY18, BNL continued helping FLIR to integrate the instrument prototype, improving the readout software and testing electronics. BNL and LLNL carried out more measurements with the 4x4 arrays in laboratory conditions using several Cs sources and reanalyzed the raw data from the field measurements. LLNL processed the old recalibrated data and new data collected in the lab. These efforts allowed us to understand the cause of the discrepancies observed during the measurements at the Westinghouse Fuel Fabrication Facility (WFFF). The problem was traced back to the original ASIC and DAQ firmware provided by the ASIC developers. A program error and some other deficiencies were identified in the original firmware. These problems, which caused missing some detected events from the data stream, never showed up in the lab environment. So, they were not spotted before the field test. The ASIC designers are currently working to address these problems and will provide the updated firmware for the next field measurements.