Measurement of differential cross sections for evaluation of radiation dose of ten’s of MeV neutrons

Double differential cross sections of several ten’s of MeV neutron induced reactions for elements composing the human tissue were measured using specially designed spectrometers at TIARA 7Li(p,n) neutron source. In spectroscopy of particles from neutron induced reactions, a large solid angle and particle acceptance detector is indespensable. For particles from 5 MeV a to 70 MeV proton, a spectrometer consisting of three counter telescopes and a vacuum chamber was used. For heavier particles, a Bragg curve spectroscopy technique was adopted to neutron field. Double differential cross section of p,d,t,a emission for N and O were obtained using the former spectrometer. In the later method we fabricated a test spectrometer to check applicability and signal to noise ratio in neutron field. Using the spectrometer, energy spectra of heavier particles (Li, Be, B, C) from carbon were observed.