The mechanism of the reaction12C(n, n )3 at 14.18 MeV neutron energy

Abstract

A detailed study in photoemulsions of the reaction 12C(n, n)3α excited by neutrons of energy 14.18 ± 0.05 MeV has provided information on the reaction mechanism. About 50% of the events are attributed to the mode 12C(n, n)12C*, 12C*(α)8Be* -> 2α, most of the remainder being due to 12C(n, α)9Be*, 9Be*(n)8Be* -> 2α and 9Be*(α)5He*(n)α. However, the reaction 12C(n, 5He*)8Be* cannot be excluded. Four-body break-up, suggested by some authors, is unnecessary to explain the results. The 10.8 and 11.8 MeV states of 12C occur in the (n, n) reaction and the data allow the assignment 1- to the former and suggest 2- for the latter.