Abstract
A proportional counter filled with helium was irradiated with monoenergetic fast neutrons produced by bombarding thin lithium and tritium-filled zirconium targets with protons from the electrostatic generator. Angular distributions of the neutrons scattered by helium were determined by measuring the distribution in energy of the pulses from recoiling alpha-particles with a differential discriminator. Measurements were made for eleven different neutron energies from 400 kev to 2730 kev. The angular distributions were consistent with a description of the neutron-helium interaction in terms of an inverted doublet in , split by about 5 Mev.
- Received 28 December 1951
DOI:https://doi.org/10.1103/PhysRev.86.155
©1952 American Physical Society