title: Measurements of neutron spectra at depths in tissue equivalent material for fast neutron beams generated by deuterons on beryllium.
abstract: The threshold foil technique has been used to investigate the behaviour in tissue of the spectra of neutron beams produced by the bombardment of thick Be targets with 13-0 and 20-5 MeV deuterons. The results indicate a gradual "softening" with depth in tissue of the spectrum generated by 20-5 MeV deutrons which contrasts with a gradual hardening as reported by other authors. This is discussed in terms of the significance of field size and the methods used for data collection and analysis.
mesh_terms: D001608:Beryllium; D003903:Deuterium; D005214:Fast Neutrons; D009502:Neutrons; D011853:Radiobiology; D011874:Radiometry
chemical_list: D003903:Deuterium; D001608:Beryllium