A new technique for detecting neutron thresholds by using a slow neutron counter and a conventional long counter is described. By means of this technique, neutron thresholds from the deuteron bombardment of ${\mathrm{Li}}^7$ have been studied at energies from 0.4 Mev to 4.7 Mev. Thresholds were observed at energies of 1.34, 2.18, 3.37, 3.6, and 4.07 Mev. These thresholds indicate excitation levels in ${\mathrm{Be}}^8$ at 16.06, 16.72, 17.65, 17.8, and 18.19 Mev.

By the same method, excited states of ${\mathrm{B}}^{10}$ from the ${\mathrm{Be}}^9(d, n){\mathrm{B}}^{10}$ reaction were found at 4.78, 5.11, 5.17, 5.93, 6.06, 6.16, 6.43, and 6.57 Mev.

• Received 16 June 1954

DOI:https://doi.org/10.1103/PhysRev.96.122