Nuclear structure effects in pion- 3He elastic scattering

Abstract

We construct two variants of the spin and isospin dependent optical potential for elastic π ±− 3He scattering. In the derivation of the potentials, the motion of target nucleons is taken into account. The structure of the 3He nucleus described by the Jackson-Elliott wave function, as well as in terms of a phenomenological model, is shown to be an important constituent of the reaction theory. Admixtures of the S' and D states in the nuclear wave function when taken into account influence more strongly the differential cross sections of the π −− 3He reaction than those of the π +− 3He reaction. A good qualitative description of the experimental data at 97 MeV and 154 MeV is achieved particularly for the reaction with positive pions. The polarization of the recoiling nucleus, the total π− 3He cross sections and the cross section of the charge-exchange 3H( π +, π 0) 3He reaction are calculated, some of their features also being discussed.