Ionization in positronium collisions with noble gases

Calculations are reported for ionizing collisions of Ps(1s) with He and Xe with emphasis on processes in which the target atom is excited/ionized. The results include total ionization cross-sections, single differential cross-sections in the longitudinal energy of the ejected particle (positron or electron) and double differential cross-sections in the angle and energy of the ejected particle. Good agreement is found with the available experiments on He but only partial agreement with some preliminary measurements of the total ionization cross-section in Xe. (c) 2007 Elsevier B.V. All rights reserved.