Measurement of the neutron capture cross section of 236-U

Abstract

In this paper we describe the 236U(n,γ) reaction cross section measurement at the GELINA white pulsed neutron source of the Institute for Reference Materials and Measurements (IRMM) in Geel. The sample was placed in the neutron beam at a flight station located at a nominal distance of 30 m from the neutron source. Neutron capture gamma rays were detected by two C6D6-based liquid scintillator gamma-ray detectors as a function of the neutron time-of-flight using the pulse height weighting technique. The pulse height weighting function has been derived from Monte Carlo simulations of the detector response to mono-energetic gamma rays. The shape of the neutron flux was measured with a 10B chamber, placed about 60 cm upstream in the neutron beam. The capture yield in the resolved resonance region up to 3 keV has been derived and will be presented here. The analysis of the capture yield in terms of Rmatrix resonance parameters is planned for the near future.