Europhys. Lett.
Volume 73, Number 1, January 2006
Page(s) 21 - 27
Section Atomic and molecular physics
Published online 23 November 2005
Europhys. Lett., 73 (1), pp. 21-27 (2006)
DOI: 10.1209/epl/i2005-10354-1

Exchange on ionization in $\chem{Ps}$-atom scattering

H. Ray

Department of Physics, Indian Institute of Technology Roorkee Roorkee 247667, Uttaranchal, India

received 29 September 2005; accepted in final form 31 October 2005
published online 23 November 2005

An improvement of the Coulomb-Born approximation is made including the effect of exchange in positronium (Ps) and atom scattering. The exchange amplitude for the simplest Ps-H system is a nine-dimensional integral. We developed a methodology of evaluating the Coulomb-Born-Oppenheimer amplitude for Ps-atom scattering and apply it to calculate the Ps-ionization cross-sections in Ps-H and Ps-He collisions. We present the first and preliminary results using the present methodology.

36.10.Dr - Positronium, muonium, muonic atoms and molecules.
34.70.+e - Charge transfer.
82.30.Gg - Positronium chemistry.

© EDP Sciences 2005