Calculation of electron induced ionization cross sections of fusion plasma relevant material: W atoms

Abstract

The electron induced processes on tungsten (W) and related materials are of prime importance for the fusion plasma application purposes. W and tungsten based materials have been recommended as the plasma facing components such as walls and divertors in the current fusion devices. We report electron impact total ionization cross sections (TICS) for the W atoms. We also report the direct ionization cross sections for the 4f, 5d, 5p and 6s sub shells of the ground state W. The ionization cross sections have been calculated in the variants of distorted wave approximation (DWA) using Hartree-Fock wavefunctions and distorted potential. We have also calculated ionization cross sections in simpler modified Kim and modified Khare models with scaling laws. Present TICS results have been compared with the other available theoretical results. Reasonable agreement with the existing theoretical results have been obtained for the TICS of W atoms by present distorted wave and BEB approaches. The majority of contribution to the total ionization cross section comes from the direct ionization of 6s and 5d subshells.