Electron impact ionization differential cross sections of W+ in the distorted-wave Born approximation.

We report electron impact triple-differential cross sections (TDCSs) for the ionization of W+ (6s) and W+ (5d) in the intermediate energy range. The TDCSs are obtained at projectile energies of 100, 200, and 500 eV for ejected electron energies of 2 and 10 eV in the distorted-wave Born approximation approach. Tungsten and related materials are prime candidates for building plasma-facing components in fusion devices, and tungsten and its ions enter the plasma as an impurity. The electron-induced processes from tungsten ions are very important for the diagnostics and modelling of plasma. In the present study, we report the kinematically complete cross section data for the ionization of tungsten ions, which will be helpful for the particular application in fusion plasma. The TDCS trends observed for W+ (6s) and W+ (5d) are analysed in terms of binary and recoil peak positions and magnitude, and a sensitive dependence on values of momentum transfer is observed. It is further observed that the TDCS trends are very different for W+ (5d), which may be due to the open d shell, and thus further investigation is required for a complete understanding of the collision dynamics. [ABSTRACT FROM AUTHOR]