Alpha-particle emission probabilities of 231Pa derived from first semiconductor spectrometric measurements

E García-Toraño; T Crespo; M Marouli; V Jobbágy; S Pommé; P Ivanov

doi:10.1016/j.apradiso.2019.108863

Alpha-particle emission probabilities of ²³¹Pa derived from first semiconductor spectrometric measurements

Appl Radiat Isot. 2019 Dec:154:108863. doi: 10.1016/j.apradiso.2019.108863. Epub 2019 Aug 14.

Authors

E García-Toraño¹, T Crespo², M Marouli³, V Jobbágy³, S Pommé³, P Ivanov⁴

Affiliations

¹ Ciemat, Avenida Complutense 40, 28040, Madrid, Spain. Electronic address: e.garciatorano@ciemat.es.
² Ciemat, Avenida Complutense 40, 28040, Madrid, Spain.
³ European Commission, Joint Research Centre (JRC), Geel, Belgium.
⁴ National Physical Laboratory (NPL), Teddington, UK.

PMID: 31513990
DOI: 10.1016/j.apradiso.2019.108863

Abstract

The nuclide ²³¹Pa is a member of the ²³⁵U decay chain. It is a complex alpha emitter with 25 identified alpha emissions. Formerly published alpha-particle emission probabilities were derived from measurements taken with magnetic spectrometers. This work presents the first measurements made with semiconductor detectors. High-resolution alpha-particle spectrometry was carried out at CIEMAT and JRC using ion-implanted planar silicon detectors. Alpha-particle emission probabilities of 23 transitions were derived from deconvolutions of the spectra. For the major lines, uncertainties are lower than 1%, a significant improvement to existing data. The new data set will allow a more accurate evaluation of the decay scheme of ²³¹Pa.

Keywords: Alpha-particle emission probabilities; Geochemistry; Nuclear decay data; Nuclear forensics; Protactinium-231; Semiconductor detector.