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Be 9 ( n , 2 n )Be 8 and Bn 11 ( n , α)Li 8 (β)Be 8 reactions induced by 14 Mev neutrons were studied by the method of beryllium and boron loaded nuclear emulsions. In the former reaction, the angular distributions of Be 8 nuclei were strongly peaked backward in the center-of-mass system, suggesting that the direct interaction of the incident neutrons with beryllium–an inelastic scattering process before second neutron emission and a pick-up process probably–had a major contribution to the reaction. The cross sections were measured as 0.18±0.07, 0.03±0.02, 0.11±0.04 and 0.05±0.03 barns for the 3, 5, 7.5 and more than 9 Mev excited states of Be 8 respectively. When 0.17±0.03 barns was cited to the cross section with respect to its ground state, the total ( n , 2 n ) cross section was estimated as 0.54±0.09 barns. The cross section of the latter reaction was measured as 35±7 millibarns in which the contribution of Be 8 in the ground state was not included. Most Li 8 nuclei were found to be left at the states lower than 2.5Mev in the reaction. The decaying rates of Li 8 to the Be 8 states of 3, 5 and more than 8 Mev were about 75, 15 and 10% respectively and the mixing of the allowed transitions of such rates was consistent with the known β-spectrum of Li 8 .
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