Neutron Spectra Measurement and Comparison of the HFR and THOR BNCT Beams

Abstract

This paper aims to measure the spectra of HB11 (HFR) and the THOR BNCT beams by multiple activation foils. The self-shielding corrections were made with the aid of MCNP calculations. The initial spectra were adjusted by a sophisticated process named coarse-scaling adjustment using SAND-EX, which can adjust a given coarse-group spectrum into a fine-group structure, i.e. 640 groups, with excellent continuity. The epithermal neutron flux of the THOR beam is about three times of HB11. The thermal neutron flux, boron and gold reaction rates along the central axis of a PMMA phantom are calculated for both adjusted spectra for comparison.JRC.F.4-Safety of future nuclear reactor