Feshbach resonances in positron scattering from sodium
Center for Theoretical Atomic and Molecular Physics, Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin 150080, P.R. China
Received: 10 September 2011
Received in final form: 28 November 2011
Published online: 28 February 2012
S-, P- and D-wave Feshbach resonances in positron-sodium scattering have been investigated by using the momentum space coupled-channels optical method. The target continuum and positronium (Ps) formation channels are included via an optical potential. Feshbach resonances below the target excitation and Ps (n = 2) formation thresholds are predicted and the effects of channel-coupling scheme, target continuum and Ps formation channels on the resonance energy and resonance width are discussed. We have also found the Wigner cusp structures at the inelastic channel-opening thresholds in positron-sodium scattering cross sections.
Key words: Atomic and Molecular Collisions
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2012