The Disintegration of Lithium by Deuterons

The following disintegrations have been studied in the range of deuteron energy from 100 to 250 kv: $\{{}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^7{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^2{}_{}{}^{},\to {}_2{}^{}{}_{}{}^{}\mathrm{He}_{}^4{}_{}{}^{}+{}_2{}^{}{}_{}{}^{}\mathrm{He}_{}^4{}_{}{}^{}+{}_0{}^{}{}_{}{}^{}n_{}^1{}_{}{}^{}+Q_1\}\{{}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^6{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^2{}_{}{}^{},\to {}_2{}^{}{}_{}{}^{}\mathrm{He}_{}^4{}_{}{}^{}+{}_2{}^{}{}_{}{}^{}\mathrm{He}_{}^4{}_{}{}^{}+Q_2\}\{{}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^6{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^2{}_{}{}^{},\to {}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^7{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^1{}_{}{}^{}+Q_{3a}\}\{{}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^6{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^2{}_{}{}^{},\to {}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^{7*}{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^1{}_{}{}^{}+Q_{3b}\}\{{}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^{7*}{}_{}{}^{},\to {}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^7{}_{}{}^{}+h\nu \}\{{}_3{}^{}{}_{}{}^{}\mathrm{Li}_{}^7{}_{}{}^{}+{}_1{}^{}{}_{}{}^{}\mathrm{H}_{}^2{}_{}{}^{},\to {}_2{}^{}{}_{}{}^{}\mathrm{He}_{}^5{}_{}{}^{}+{}_2{}^{}{}_{}{}^{}\mathrm{He}_{}^4{}_{}{}^{}+Q_4\}$ Efficiency curves for (1), (2) and (3a) are regular. It is concluded that the Oppenheimer-Phillips process is not applicable to (3a). The relative yield of (3b) to (3a) increases with increasing deuteron energy. The return of the excited Li nucleus in (3b) to its normal state is shown by the emission of a gamma-ray of 400 kv energy as determined by absorption measurements. The existence of a homogeneous group of particles from (4) is interpreted as evidence for the instability of ${\mathrm{He}}^5$, which has a mean life of approximately 6×${10}^{-20\mathrm{}}$ sec. and is unstable by 0.93 Mev, disintegrating into an alpha-particle and a neutron. Absolute yields for the five disintegrations studied are given for a deuteron energy of 212 kv.