Abstract
The value of Auger electron lineshapes measured in coincidence with outgoing scattered electrons following electron impact inner-shell ionisation in free atoms is discussed. Preliminary data of this type are reported for the first time. Measurements for the L2-M2,3M2,3(3P0,1,2) line of argon confirm the feasibility of the technique for the study of post-collision interaction effects in Auger electron decay. The data are compared with the semiclassical calculations of Niehaus (1977) for photoionisation.