The stochastic variational method is used with a confining potential of the form V=? r12 to generate correlated basis sets capable of accurately describing low-energy elastic scattering. Stabilization concepts are then used to extract the phase shifts and other scattering observables. The method is applied to positron scattering from H and He, and Ps scattering from H and He. The results of the calculations are in uniformly good agreement with previous high quality calculations or with experiment. In particular, the scattering length for Ps-He scattering is found to be 1.566 a0 while the zero-energy Z1 eff was 0.1157. The Ps-He s -wave phase shift is found to be incompatible with experimental momentum transfer cross sections obtained by the Doppler broadening technique. � 2008 The American Physical Society.
|Number of pages||11|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|Publication status||Published - 2008|