The energy distribution of protons from the bombardment of ${\mathrm{Be}}^9$ with protons has been investigated by precision magnetic analysis in the region of excitation from the ground state through the 2.43-Mev state. A broad distribution of protons was found with a cutoff corresponding to a $Q$ of -1.675±0.002 Mev in ${\mathrm{Be}}^9$. The asymmetry of the observed group and the proximity of the observed $Q$-value to the separation energy of a neutron from ${\mathrm{Be}}^9$ suggests that the group consists of protons from the three body disintegration ${}_{}{}^{*}{}_{}{}^{}\mathrm{B}_{}^{10}{}_{}{}^{}\to {\mathrm{Be}}^8+p+n$, but the possibility of inelastic scattering to a state in ${\mathrm{Be}}^9$ cannot be excluded. An excitation energy of 2.432±0.004 Mev was found for the inelastic proton group from the known state, and a natural width ≤1 kev is ascribed to this state from experiments conducted at optimum resolution.

• Received 20 June 1955

DOI:https://doi.org/10.1103/PhysRev.100.203