The following reactions were studied. At $E_h=6.2\mathrm{}$ MeV: ${\mathrm{B}}^{10}(h, n){\mathrm{N}}^{12}$. At $E_h=10\mathrm{} \mathrm{and} 11$ MeV: ${\mathrm{B}}^{10}(h, n){\mathrm{N}}^{12}\mathrm{}\left(p\right)\mathrm{}{\mathrm{C}}^{11}$, ${\mathrm{B}}^{10}(h, p){\mathrm{C}}^{12}\mathrm{}\left(n\right)\mathrm{}{\mathrm{C}}^{11}$, ${\mathrm{B}}^{10}(h, p){\mathrm{C}}^{12}\mathrm{}\left(p\right)\mathrm{}{\mathrm{B}}^{11}$, ${\mathrm{B}}^{10}(h, p){\mathrm{C}}^{12}\left(\alpha \right){\mathrm{Be}}^8$, ${\mathrm{B}}^{10}(h, p){\mathrm{C}}^{12}\mathrm{}\left(d\right)\mathrm{}{\mathrm{B}}^{10}$. States at 5.3 MeV in ${\mathrm{N}}^{12}$ and 20.5 MeV in ${\mathrm{C}}^{12}$ were identified as members of an isobaric triad, with $J^{\pi }$, $T=3^{+}, 1$ having a pronounced two-particle structure. Angular correlations support this assignment. For these and other states, branching ratios of the emitted particles are measured, and conclusions on isospin purities and other properties are drawn.

• Received 14 July 1970

DOI:https://doi.org/10.1103/PhysRevC.2.2072