Secondary neutron spectra from neutron interactions in thick carbon sample

The spectra of secondary neutrons produced by neutron interactions in a thick (approximately 3 mean free path) sample of carbon have been measured as a function of the incident neutron energy over the range 1 to 20 MeV. A linac (ORELA) was used as a white neutron source with a 48-m flight path. Incident energy was determined by time-of-flight, while secondary spectra were obtained through pulse-height unfolding techniques. The results of the measurement are compared to calculations based on the current evaluated data file