(π+,p) and (π+,d) reactions on light nuclei

The (π+,p) and (π+,d) reactions on 1p shell nuclei are studied between T/sub π/ = 32 and 81 MeV. The cross sections to both the continuum and discrete two-body final states are given. The spectra and angular distributions of the (π+,p) continuum are interpreted in terms of a two-nucleon pion absorption mechanism. The 13C(π+,p) spectrum of discrete states is similar to the 13C(p,d) spectrum at the same momentum transfer. The two-neutron-pickup (π,d) reaction is found to strongly favor transitions in the 1p shell of angular momentum transfer, L = 2. The relative strength of these transitions varies the same way as the corresponding (p,t) cross sections. No L = 0 transitions are clearly identifiable. There is an indication of the S = 1 7Li(π+,d)5Li(16.7 MeV) 3/2+ transition, contrary to the prediction that S = 1 transitions are suppressed. The (π+,d) angular distributions are compared to the calculations of Betz and Kerman. 2 tables