Alpha-particle emission probabilities of 236U obtained by alpha spectrometry

High-resolution alpha-particle spectrometry was performed with an ion-implanted silicon detector in vacuum on a homogeneously electrodeposited 236U source. The source was measured at different solid angles subtended by the detector, varying between 0.8% and 2.4% of 4π sr, to assess the influence of coincidental detection of alpha-particles and conversion electrons on the measured alpha-particle emission probabilities. Additional measurements were performed using a bending magnet to eliminate conversion electrons, the results of which coincide with normal measurements extrapolated to an infinitely small solid angle.The measured alpha emission probabilities for the three main peaks – 74.20 (5)%, 25.68(5)% and 0.123 (5)%, respectively – are consistent with literature data, but their precision has been improved by at least one order of magnitude in this work.JRC.D.4-Standards for Nuclear Safety, Security and Safeguard