Neutron yields from thick Be targets bombarded with deuterons or protons

Abstract

Thick target yields of the neutron producing reactions d + Be and p + Be were investigated for deuteron energies between 9.4 and 13.6 MeV and proton energies between 17.2 and 22.0 MeV. The spectral neutron yield per unit beam charge on the Be target was determined by using time-of-flight techniques and the (n, γ) discrimination properties of an NE213 scintillation detector. In addition, the angular dependence of the spectral neutron yield was measured between 0° and 150° for a deuteron energy of 13.54 MeV and a proton energy of 19.08 MeV. The spectral neutron yield at 0° as a function of the incident particle energy, which is approximated by a simple function obtained from a least-squares fit, is compared with previous data. Fluence-averaged mean neutron energies of the neutron spectra are given as a function of the charged particle energy and neutron emission angle for various neutron energy thresholds. The present neutron spectra differ in the low-energy portion from those published by other authors. Deviations of up to 20% are found in the total neutron yield per unit beam charge at 0°.