Year
2023
File Attachment
finalpaper_142_0510015204.pdf10.78 MB
Abstract
We report observation of the 103-keV and 159-keV gamma ray signatures of 242 Pu using the
SOFIA microcalorimeter gamma-ray spectrometer. This is the first observation of these gamma
rays in a non-destructive measurement of an unprepared sample, and so represents an important
advance in nuclear material accountancy. We extract the gamma emission probabilities at these
two energies and compare with prior destructive analysis results. We also confirm that several
public databases include an order-of-magnitude error in the emission probabilities at 103 keV, and
report an improved centroid energy for this peak.