Neutron Data Measurements at IRMM

Abstract

An overview is presented of recent neutron data measurements and equipment developments at IRMM. Neutron data activities are organised in two main activities, the first is centered on nuclear waste minimisation and, more generally, nuclear safety, while the second concentrates on neutron standards and basic science. Neutron data measurements at IRMM use two neutron-production facilities, the white pulsed neutron source GELINA for very high resolution neutron time-of-flight measurements from thermal to 20 MeV and the Van de Graaff quasi mono-energetic neutron source which covers the range from 0.1 to 20 MeV. At GELINA current campaigns concentrate on (n,xngamma) cross section measurements for isotopes of lead and for bismuth, on capture and total cross section measurements for criticality safety in a collaboration with US-DOE, and on fission of 236U and on the 10B(n,alpha) standard. At the Van de Graaff laboratory current work concerns the fission process ¿ fission isomers, the fission neutron spectrum, neutron multiplicity and fission fragment distributions ¿, the study of light charged particle emission in neutron-induced reactions on lithium, carbon and oxygen, and the study of activation cross sections on Cr, Ni, Cu, Zr, Ta and W. Various technical developments are underway to allow new and/or improved studies of cross sections in the coming years. These include, an array of eight high purity germanium detectors for the study of (n,xngamma) cross sections on structural materials and fission products, an array of 10 C6D6 detectors in close-packed geometry for capture studies, the VERDI fission fragment spectrometer and the NEPTUNE facility