Eur. Phys. J. D (2015) 69: 235
https://doi.org/10.1140/epjd/e2015-60315-1

Regular Article

A coincidence study of electron and positron impact ionization of Ar (3p) at 1 keV

¹ Department of Physics and Astronomy, York University, Toronto, Ontario M3J 1P3, Canada
² Centre for Theoretical Atomic, Molecular, and Optical Physics, School of Mathematics and Physics, Queens University, Belfast BT7 1NN, UK
³ Physics Department, Old Dominion University, Norfolk, Virginia, USA

^a e-mail: campeanu@yorku.ca

Received: 28 May 2015
Received in final form: 22 August 2015
Published online: 29 October 2015

Abstract

Distorted-wave calculations of the triple differential cross section (TDCS) are presented for electron and positron impact ionization of Ar(3p) in coplanar asymmetric geometry at an impact energy of 1 keV and are compared with a recent experiment. The experiment indicates that the positron TDCS is generally larger than the equivalent electron TDCS. It is shown that the magnitude of the TDCS is extremely sensitive to the energy of the ejected electron and that only when the cross section is averaged over energy do we get a reasonable agreement with experiment.