Regular Article

Correlation ν̅_p − σ − χ in the fast neutron range via integral information

¹ Laboratory for Reactor Physics Systems Behaviour, Paul Scherrer Institut, Villigen, Switzerland
² CEA, DAM, DIF, 91297 Arpajon cedex, France

^⁎ e-mail: dimitri-alexandre.rochman@psi.ch

Received: 18 January 2017
Received in final form: 20 March 2017
Accepted: 20 March 2017
Published online: 15 May 2017

Abstract

This paper presents a Bayesian approach based on integral experiments to create correlations which do not appear with differential data. Some quantities such as the fission cross section (σ), neutron multiplicity (ν̅_p), neutron spectra (χ), etc. are usually neither modeled together nor measured in coincidence, thus there is no correlation matrices in evaluated nuclear data libraries. One can nevertheless use the information from integral experiments such as fast criticality-safety benchmarks to correlate such quantities for possible inclusion in nuclear data libraries. A simple Bayesian set of equations is presented with random nuclear data, similarly to the usual methods applied with differential data. An example for ²³⁹Pu is proposed.