Year
2005
Abstract
Ultra-high energy resolution ?-spectrometers can improve the precision of nondestructive Pu isotope analysis, since a better line separation reduces statistical errors from line overlap as well as systematic errors from background subtraction and detector efficiency corrections. In particular, they could allow the direct detection of 242Pu though its ?-emission at 103.5 keV, which is usually obscured by strong 239Pu, 241Pu and 241Am lines. Cryogenic ?-ray spectrometers operating at 0.1 K offer an order of magnitude improvement in energy resolution over conventional high-purity germanium detectors. Their resolution below 100 eV FWHM at 100 keV will significantly improve the precision of Pu isotopics, provided their effective area and total count rate can be increased. We describe the performance of current cryogenic ?-detectors, quantify the limiting errors for isotopic analysis of Pu for different spectrometers, and discuss the detector array development required for direct detection and quantification of 242Pu.