Reproducibility and calibration of MMC-based high-resolution gamma detectors

We describe a prototype gamma-ray detector based on a metallic magnetic calorimeter with an energy resolution of 46eV at 60 keV and a reproducible response function that follows a simple second-order polynomial. The simple detector calibration allows adding high-resolution spectra from different pixels and different cool-downs without loss in energy resolution to determine c-ray centroids with high accuracy. As an example of an application in nuclear safeguards enabled by such a c-ray detector, we discuss the non-destructive assay of Pu-242 in a mixed-isotope Pu sample. Published by AIP Publishing.