The 14.2 and 14.5 MeV levels of 15O formed via 3He bombardment of 12C

Abstract The alpha-particle core-excited threshold state (APCETS) model indicates that the 14.2 and 14.5 MeV levels in 15 O are formed by coupling an L = 1 alpha particle to the 1 2 − first excited state of 11 C. Detailed measurements of the cross section as a function of energy and angle for the 12 C( 3 He, 3 He) 12 C and the 12 C ( 3 He, a0) 11 C reactions have been obtained for incident 3 He energies of 2.3 to 3.3 MeV. The elastic data were analyzed by means of an optical model plus resonance (OMPR) formulation. A Legendre polynomial analysis was performed on the a0 data. The results indicate a 1 2 + assignment for the level at 14.2 MeV and a ( 3 2 + , 5 2 + ) assignment for the 14.5 MeV level. These assignments are in accord with the APCETS model.