Alpha-particle emission probabilities in the decay of Pu-240

Sources of enriched Pu-240 were prepared by vacuum evaporation on quartz substrates. High-resolution alpha-particle spectrometry of Pu-240 was performed with high statistical accuracy using silicon detectors and with low statistical accuracy using a bolometer The alpha-particle emission probabilities of six transitions were derived from the spectra and compared with literature values. Additionally, some alpha-particle emission probabilities were derived from gamma-ray intensity measurements with a high-purity germanium detector The alpha-particle emission probabilities of the three main transitions at 5168.1, 5123 6 and 5021.2 key were derived from seven aggregate spectra analysed with five different fit functions and the results were compatible with evaluated data. Two additional weak peaks at 4863 5 and 4492.0 key were fitted separately, using the exponential of a polynomial function to represent the underlying tailing of the larger peaks. The peak at 4655 key could not be detected by alpha-particle spectrometry, while gamma-ray spectrometry confirms that its intensity is much lower than expected from literature. (C) 2009 Elsevier Ltd All rights reserved