Discovery of a P-odd effect in triton emission from the reaction 6Li(n, α)3H

The results of measuring the P-odd asymmetry (S _n · P _t) for triton emission from the reaction ⁶Li(n, α)³H are presented. Here, S _n is the neutron spin and P _t is the triton momentum. Three series of measurements were performed, one at the Petersburg Nuclear Physics Institute (Gatchina, Russia) in a vertical neutron beam from the PWR reactor and two in the PF1B beam from the reactor at the Institute Laue-Langevin (Grenoble, France). On the basis of all three experiments, the P-odd asymmetry coefficient was found to be α_PN = −(8.6 ± 2.0) × 10⁻⁸. The results of zero experiments and calculations give every reason to believe that the above P-odd asymmetry is due to the reaction being studied.