A comparison of untagged gamma-ray and tagged-neutron yields from 241AmBe and 238PuBe sources

J Scherzinger; R Al Jebali; J R M Annand; K G Fissum; R Hall-Wilton; S Koufigar; N Mauritzson; F Messi; H Perrey; E Rofors

doi:10.1016/j.apradiso.2017.05.014

A comparison of untagged gamma-ray and tagged-neutron yields from ²⁴¹AmBe and ²³⁸PuBe sources

Appl Radiat Isot. 2017 Sep:127:98-102. doi: 10.1016/j.apradiso.2017.05.014. Epub 2017 May 16.

Authors

J Scherzinger¹, R Al Jebali², J R M Annand², K G Fissum³, R Hall-Wilton⁴, S Koufigar⁵, N Mauritzson⁵, F Messi¹, H Perrey¹, E Rofors⁵

Affiliations

¹ Division of Nuclear Physics, Lund University, SE-221 00 Lund, Sweden; Detector Group, European Spallation Source ESS AB, SE-221 00 Lund, Sweden.
² SUPA School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, UK.
³ Division of Nuclear Physics, Lund University, SE-221 00 Lund, Sweden; Detector Group, European Spallation Source ESS AB, SE-221 00 Lund, Sweden. Electronic address: kevin.fissum@nuclear.lu.se.
⁴ Detector Group, European Spallation Source ESS AB, SE-221 00 Lund, Sweden; Mid-Sweden University, SE-851 70 Sundsvall, Sweden.
⁵ Division of Nuclear Physics, Lund University, SE-221 00 Lund, Sweden.

PMID: 28564615
DOI: 10.1016/j.apradiso.2017.05.014

Abstract

Untagged gamma-ray and tagged-neutron yields from ²⁴¹AmBe and ²³⁸PuBe mixed-field sources have been measured. Gamma-ray spectroscopy measurements from 1 to 5MeV were performed in an open environment using a CeBr₃ detector and the same experimental conditions for both sources. The shapes of the distributions are very similar and agree well with previous data. Tagged-neutron measurements from 2 to 6MeV were performed in a shielded environment using a NE-213 liquid-scintillator detector for the neutrons and a YAP(Ce) detector to tag the 4.44MeVgamma-rays associated with the de-excitation of the first-excited state of ¹²C. Again, the same experimental conditions were used for both sources. The shapes of these distributions are also very similar and agree well with previous data, each other, and the ISO recommendation. Our ²³⁸PuBe source provides approximately 2.6 times more 4.44MeVgamma-rays and 2.4 times more neutrons over the tagged-neutron energy range, the latter in reasonable agreement with the original full-spectrum source-calibration measurements performed at the time of their acquisition.

Keywords: Americium-beryllium; Cerium-bromide; Fast neutrons; Gamma-rays; NE-213; Plutonium-beryllium; Pulse-shape discrimination; Time-of-flight.