The $\mathrm{D}(\alpha , pd)\mathrm{T}$ and $\mathrm{D}(\alpha , dt)\mathrm{H}$ sequential reactions through ${}_{}{}^4{}_{}{}^{}\mathrm{H}$* and ${}_{}{}^5{}_{}{}^{}\mathrm{He}$* are investigated in a kinematically complete experiment with $E_{\alpha }=70\mathrm{}$ MeV, particle identification, and online computer coincidence electronics. Data analysis of various $p-d$ and $d-t$ coincidence spectra are presented. Sequential decay through the 20.1-, 21.4-, and 22.4-MeV states of ${}_{}{}^4{}_{}{}^{}\mathrm{He}$ and the 16.7-MeV states of ${}_{}{}^5{}_{}{}^{}\mathrm{He}$ are observed. The results are in good agreement with previous work on ${}_{}{}^4{}_{}{}^{}\mathrm{He}$* and spectral structure due to ${}_{}{}^5{}_{}{}^{}\mathrm{He}$ excited states is suggestive of narrow states at 18.6, 18.8, and 19.2 MeV of excitation.

• Received 18 September 1972

DOI:https://doi.org/10.1103/PhysRevC.7.1742