INVESTIGATION OF BOHR-INDEPENDENCE HYPOTHESIS FOR NUCLEAR REACTIONS IN CONTINUUM . ALPHA+CO-59, P+NI-62 AND ALPHA+FE-56, P+CL-59

Measurements were made of the energy spectra at various angles of protons and α particles emitted from the reactions of protons with Ni62 and α particles with Co59 to determine the extent to which the deexcitation of the reaction intermediate, Cu63 at 20.2-MeV excitation energy, is independent of its mode of formation. Similarly, the reaction intermediate Ni60 at 23.6 MeV was formed by protons on Co59 and α particles on Fe56, again to determine to what degree its deexcitation by proton and α-particle emission is independent of its mode of formation. Small differences in the shapes of corresponding energy spectra [(p,p′) versus (α,p), and (α,α′) versus (p,α)] that were observed in apparent violation of the Bohr-independence hypothesis are removed after account has been taken of the effects of angular-momentum conservation. The observed enhancement of the ratio of cross sections σ(x,p)σ(x,α) for the proton entrance channel over that for the α entrance channel cannot be interpreted in terms of angular-momentum conservation. The consequences of the possibility of isotopic-spin conservation, when considered, lead to enhanced proton reemission similar to that observed experimentally. © 1969 The American Physical Society.