Stripping-theory analysis of thick-target neutron production for D+Be (and tissue dose calculation)

Abstract

The Serber theory for deuteron stripping is employed to predict the shape of the neutron energy spectrum produced by 35 MeV deuterons (D+) on a thick beryllium target. In particular, the observation that the maximum of the neutron energy spectrum (at O degrees relative to the deuteron beam direction) occurs at approximately 0.4Ed, where Ed is the incident deuteron energy, is explained reasonably well by the calculations. The application of this theory also accounts for the previously observed Ed2.99 dependence of the absorbed dose in tissue, per unit charge of D+ ions on target, in the direction of the incident beam. This approximate Ed3 dependence is shown to be a characteristic property of deuteron stripping in a thick target and follows directly from the calculations that predict the neutron energy spectrum.