Determination of Accelerator-Based Neutron Energy Distribution by Means of Multiple-Foil Activation Method Using GRAVEL, MAXED, and RooUnfold

Abstract

A multiple-foil activation method is one of the effective measurement methods of neutron energy distribution. Unfolding processes play an important role in the method. The performance of three unfolding codes, GRAVEL, MAXED, and RooUnfold is compared by using the newly measured data of double-differential thick-target neutron yield (DDTTNY) from the C(d,n) reaction induced by 20-MeV deuteron. The DDTTNYs unfolded by GRAVEL and MAXED show the energy distributions similar to that measured previously by a conventional time of flight (TOF) method, while the DDTTNY unfolded by RooUnfold leads to harder energy distribution than the TOF result.