Caffrey, Gus | Engineering Papers

DOE OSTI2013

Summary Report: INL CDCIS Cask Scanner Testing at Doel, Belgium

In October and November 2012 the INL Compton Dry-Cask Imaging Scanner (CDCIS) was packaged and transported to the Doel Nuclear Power Plant near Antwerp, Belgium to perform a series of measurements on spent fuel storage casks. The task was performed in support of the DOE/NNSA NA-241 IAEA request 09/TAU-10 Restoration of CoK of LWR Fuel Assemblies by Gamma Scanning from the Top of Casks. The purpose of the measurements was to determine whether the system could by passive detection of the gamma rays being emitted by the contained spent fuel, confirm the presence or absence of the nuclear fuel bundles in a known, verified dry storage cask. If successful, the system, would be used to confirm the presence of the nuclear fuel bundles on four casks in storage that had lost continuity of knowledge due to problems verifying the status of the casks’ Tamper Indicating Device (TID) seals.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2011

Automatic Energy Calibration of Gamma-Ray Spectrometers

The software provides automatic method for calibrating the energy scale of high-purity germanium (HPGe) and scintillation gamma-ray spectrometers, using natural background radiation as the source of calibration gamma rays. In field gamma-ray spectroscopy, radioactive check sources may not be available; temperature changes can shift detector electronic gain and scintillator light output; and a user's experience and training may not include gamma-ray energy calibration. Hence, an automated method of calibrating the spectrometer using natural background would simplify its operation, especially by technician-level users, and by enhancing spectroscopic data quality, it would reduce false detections. Following a typically one-minute count of background gamma-rays, the measured spectrum is searched for gamma-ray peaks, producing a list of peak centroids, in channels1. Next, the ratio algorithm attempts to match the peak centroids found in the search to a user-supplied list of calibration gamma-ray energies. Finally, if three or more calibration energies have been matched to peaks, the energy equation parameters are determined by a least-squares fit2, and the spectrum has been energy-calibrated. The ratio algorithm rests on the repeatable but irregular spacing of the background gamma-ray energies together they form a unique set of ratios, when normalized to the highest energy calibration gamma ray; so too, the corresponding peak centroids in the spectrum. The algorithm matches energy ratios to peak centroid ratios, to determine which peak matches a given calibration energy.

Caffrey, Gus↗

DOE OSTI2011

Compton Dry-Cask Imaging System

The Compton-Dry Cask Imaging Scanner is a system that verifies and documents the presence of spent nuclear fuel rods in dry-cask storage and determines their isotopic composition without moving or opening the cask. For more information about this project, visit http://www.inl.gov/rd100/2011/compton-dry-cask-imaging-system/

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗