The Neutrons emitted in the Bombardment of¹⁰B and¹¹B by Deuterons

The photographic plate method has been used in an investigation of the neutrons from the (dn) reactions in 10 B and 11 B, separated isotopes being used in the targets. The reaction 10 B(dn) 11 C gives neutron groups at 6.70 MeV. and 4.85 MeV.; these give an energy release for the transition to the ground state of 6.59±0.10 MeV., and show the existence of a level in 11 C at 2.02±0.10 MeV. The reaction 11 B(dn) 12 C gives well-defined neutron groups at 13.51 MeV., 9.40 MeV. and 4.55 MeV., with a continuous distribution up to 6 MeV. and a small peak at 6.4 MeV. The 13.51 MeV. group gives an energy release of 13.92±0.15 MeV. for the transition to the ground state; the other groups confirm the existence of levels in 12 C at 4.47±0.10 MeV., 9.72±0.15 MeV. and less certainly 7.7 MeV., while the continuous distribution is due to the reaction 11 B(dn)3α.