Regular Article

Measurements of the effective cumulative fission yields of ¹⁴³Nd, ¹⁴⁵Nd, ¹⁴⁶Nd, ¹⁴⁸Nd and ¹⁵⁰Nd for ²³⁵U in the PHENIX fast reactor

¹ CEA, DEN Cadarache, 13108 Saint Paul Les Durance, France
² Centre d’Etudes Nucléaires Bordeaux Gradignan, CNRS/IN2P3, Univ. Bordeaux 1, 33175 Gradignan, France
³ National Nuclear Laboratory, B170 Sellafield Works, Seascale, Cumbria CA20 1PG, UK

^⁎ e-mail: gilles.noguere@cea.fr

Received: 8 March 2016
Received in final form: 13 June 2016
Accepted: 20 June 2016
Published online: 23 August 2016

Abstract

The effective Neodymium cumulative fission yields for ²³⁵U have been measured in the fast reactor PHENIX relatively to the ²³⁵U fission cross-section. The data were derived from isotope-ratio measurements obtained in the frame of the PROFIL-1, PROFIL-2A and PROFIL-2B programs. The interpretations of the experimental programs were performed with the ERANOS code in association with the Joint Evaluated Fission and Fusion library JEFF-3.1.1. Final results for ¹⁴³Nd, ¹⁴⁵Nd, ¹⁴⁶Nd, ¹⁴⁸Nd and ¹⁵⁰Nd were 5.61%, 3.70%, 2.83%, 1.64% and 0.66%, respectively. The relative uncertainties attached to each of the cumulative fission yields lie between 2.1% and 2.4%. The main source of uncertainty is due to the fluence scaling procedure (<2%). The uncertainties on the Neodymium capture cross-sections provide a contribution lower than 1%. The energy dependence of the fission yields was studied with the GEF code from the thermal energy to 20 MeV. Neutron spectrum average corrections, deduced from GEF calculations, were applied to our effective fission yields with the aim of estimating fission yields at 400 keV and 500 keV, as given in the International Evaluated Nuclear Data Files (JEFF, ENDF/B and JENDL). The neutron spectrum average correction calculated for the PROFIL results remains lower than 1.5%.