Angular and impact parameter dependent electron emission in collisions of swift bare and screened heavy ions with gaseous targets

Abstract

We have measured double-differential cross sections of electron production in 3.6 MeV/u neon, xenon and 5.9 MeV/u uranium projectile collisions with gaseous many-electron targets. The paper is focused on the angular dependence of the mean ejected electron energy in the transition from bare (Ne 10+) to highly screened (U 29+) heavy ions. For some collision systems the electron spectra were measured in coincidence with projectiles that captured an electron from the target. It is well shown in results of presented nCTMC-calculations that only small impact parameters contribute to the capture process, thus comparison of coincident and non-coincident spectra reveal the impact parameter dependence of electron emission.