A Photographic Plate Spectrum of the Neutrons from the Disintegration of Lithium by Deuterons

TLDR

The energy spectrum of neutrons from Li + d was studied using photographic emulsion. The study employed photographic emulsion, correcting for track‑acceptance probabilities and measuring stopping power for three proton energies. The results confirm a broad 10.8‑MeV neutron group, show that not all neutrons arise from the 2.8‑MeV excitation of Be‑8, and provide evidence for additional 7.5‑ and 10‑MeV levels.

Abstract

The energy spectrum of the neutrons from Li+${\mathrm{H}}^{2}$ has been studied by the photographic emulsion technique. Confirmation is given of the broad 10.8-Mev neutron group reported by Stephens from He recoil data. Reasons are given for believing that not all the neutrons from this group correspond to the 2.8-Mev excitation level in the residual ${\mathrm{Be}}^{8}$ nucleus. Evidence is also given for at least two higher (7.5 Mev and 10 Mev) levels in ${\mathrm{Be}}^{8}$. A discussion of the photographic emulsion technique is included, and a correction is calculated for the differing probability that long tracks be acceptable for measurement. The stopping power of the emulsion for three different proton energies was found.