Subshell Differential Cross Sections for Electron Transfer in Collisions of U90+ Ions with Gaseous Targets

Balmer spectra produced in collisions between He-like uranium projectiles and gaseous targets (N2, Ar, Kr, and Xe) were measured at the jet-target area of the ESR storage ring. The X-ray radiation were recorded in coincidence with the down charged projectiles having captured one electron from the target atom. By means of spectra simulation, all the significant Balmer transition lines were identified. Further, the j-differential cross sections for electron capture into projectile subshells were deduced from the well resolved spectra. For the heavier targets, where NRC contributes considerably, systematic deviations between experiment and the continuum distorted wave approximation are observed