Electron impact excitation of the M-shell electrons from Zn-like through Co-like tungsten ions

Abstract

A detailed study using fully relativistic distorted wave theory for electron impact excitation of Zn-like through Co-like tungsten ions is presented in a wide range of incident electron energies up to 50 keV. We have considered electron impact excitations, namely 3d–4p and 3d–nf (n = 4–8) transitions from the M-shell of the ground state in the Zn-like W44+, Cu-like W45+, Ni-like W46+ and Co-like W47+ ions. We report excitation cross sections for these dipole allowed transitions considered in all the four ions along with the linear polarization of the photon emissions due to the decay of the excited anisotropic states to the ground state. We also provide the analytic fits to our calculated cross sections for plasma application purposes.