Energy spectrum of photoneutrons from cobalt

Abstract

The energy spectrum of the photoneutrons emitted at 90‡ from cobalt irradiated by a collimated 30 MeV bremsstrahlung beam is studied by recording the protons recoil tracks in L-4 Ilford photoemulsions 400 μm thick. The neutron spectrum is analysed in neutron energy steps of 0.5 MeV, starting from Enmin=2 MeV. A maximum around En=(4÷5) MeV in the experimental spectrum gives evidence of a contribution of other processes besides the evaporation. The interpretation of the experimental results is discussed.