Abstract
The (,) and (,) reactions on shell nuclei are studied between MeV. Cross sections both to the continuum and to discrete two body final states are given. The spectra and angular distributions of the (,) continuum are examined in terms of a two-nucleon pion absorption mechanism. The (,) spectra of discrete states are similar to the corresponding (,) spectra at the same momentum transfer. The (,)(g.s.) transition is found to have an abnormally small cross section relative to other transitions of similar spectroscopic strength. The two-neutron pickup (,) data to discrete states is the first published data on this reaction. The (,) reaction is found to favor strongly transitions in the shell of angular momentum transfer . The relative strength of these transitions varies the same way as the corresponding (,) cross sections. No transitions are clearly identifiable. The (,) angular distributions are compared to the calculations of Betz and Kerman. The calculations reproduce well the absolute magnitude and shape of the (,) angular distributions but fail to predict the dependence, pion energy dependence, and possibly even the spin transfer dependence of the (,) cross sections.
NUCLEAR REACTIONS , (,), , , , (,) MeV; measured spectral shape, for continuum and discrete states.
- Received 9 March 1981
DOI:https://doi.org/10.1103/PhysRevC.25.962
©1982 American Physical Society