J. Phys. Soc. Jpn. 22, pp. 685-697 (1967) [13 Pages]

Excitation of Spin-Flip States of Light Nuclei in Inelastic Scattering of Alpha Particles

+ Affiliations
1Department of Physics, Faculty of Science, Kyoto University

Angular distributions of inelastically scattered alpha-particles, leading to the Δ T =0 spin-flip states of C 12 at 12.7 MeV and B 11 at 8.6 MeV, were observed. These angular distributions were found to show a unique pattern. Such characteristic of the angular distributions were also observed for the 10.4 MeV state of Mg 24 and the 8.9 MeV state of Si 28 . These four states were systematically interpreted as the Δ T =0 spin-flip states by the j - j coupling shell model. The excitation mechanism for these states is discussed and it is concluded that a spin-orbit interaction between the incident alpha-particle and a nucleon in the target nucleus plays an important role. The angular distribution for another unnatural-parity state of C 12 at 11.8 MeV (2 - ). Mg 24 at 5.22 MeV(3 + ) and Si 28 at 6.27 (3 + ) were also observed. The 14.08 MeV collective state of C 12 was found to be excited strongly.

©1967 The Physical Society of Japan