The angular distribution of the two $\alpha$-particle coincidence cross sections, measured at 2 MeV incident energy, is interpreted. Since the momentum transferred to the outgoing $\alpha$ particles is high enough to minimize peripheral effects in a quasifree process, the apparent narrowing of the impulse distribution of the $\alpha -d$ motion in ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ is attributed to Coulomb effects in the entrance channel.

NUCLEAR REACTIONS ${}_{}{}^6{}_{}{}^{}\mathrm{Li}+{}_{}{}^6{}_{}{}^{}\mathrm{Li}\to 3\alpha$ at 2 MeV. Discussed angular distribution of two $\alpha$-particle coincidence cross section. Proposed subthreshold mechanism.

• Received 19 May 1982

DOI:https://doi.org/10.1103/PhysRevC.26.1330