Hans Bichsel

Reactions Li-7 (alpha, n) B-10, Li-7 (alpha, alpha-prime) Li-7*, and B-10 (n, alpha) Li-7

The nuclear reactions Li/sup 7/( alpha ,n)B/sup 10/ and Li/sup 7/( alpha , alpha )Li/sup 7*/ have been studied for monoenergetic alpha particles from a Van de Graaff accelerator. The threshold in the ( alpha ,n) reaction was measured to be 4.379 Mev which gives a Q value of -2.788 Mev. Resonances in the yield of 0.477-Mev gamma radiation were observed at alpha -particle energies of l.9l, tion B/sup 10/(n, alpha )Li/sup 7/ was also studied by using monoenergetic neutrons with energies between 0.020 and 4.80 Mev. Resonances were observed at neutron energies of 0.53, l.86, 2.8, and 4.l Mev. Excited states in B/sup 11/ from thcse expcriments are indicated at 9.88, l0.25, l0.62, l0.97, ll.46, ll.6, ll.9, l3.2, l4.0, and l5.2 Mev. (auth)