Decay Scheme and Gamma-Gamma Correlations inB10

Gamma rays from the deuteron bombardment of beryllium were studied with two scintillation spectrometers operated in coincidence. Gamma rays of energies 2.86, 2.15, 1.43, 1.02, 0.72, and 0.41 Mev, which have previously been associated with the ${\mathrm{B}}^{10}$ nucleus, were identified in single-channel spectra. Coincidences were observed between the following pairs of gamma rays: 2.86-0.72, 2.15-1.43, 1.43-1.43, 1.43-1.02, 1.43-0.72, 1.43-0.41, 1.02-0.72, 1.02-0.41, and 0.72-0.41. The decay scheme obtained from these measurements agrees with the one proposed by Ajzenberg, except for the presence of an additional 1.43-Mev transition between the 3.58- and 2.15-Mev states of ${\mathrm{B}}^{10}$. A survey was made of the directional angular correlations between several of these coincident radiations.