Atomic data and collisional ionization cross-sections by electron impact of F-like tungsten, W 65+

In the present work, we present a detailed investigation of the atomic structure and electron-impact ionization cross-sections of fluorine-like tungsten, W 65+ , a charge state of particular importance in fusion plasmas. The multiconfiguration Dirac–Hartree–Fock (MCDHF) method, implemented in the GRASP2018 code, was employed to calculate level energies, oscillator strengths, and radiative transition rates. These calculations were complemented by results from the Flexible Atomic Code (FAC) to ensure internal consistency and cross-validation. In contrast to earlier studies, we include quantum electrodynamics (QED) corrections (vacuum polarization and self-energy), allowing improved accuracy for fine-structure splitting and transition energies. The ionization cross-sections of several low-lying levels were computed in the 10–250 keV incident energy range using FAC. Comparisons with NIST and previous theoretical data demonstrate very good agreement for most levels, while highlighting specific high-lying states where QED and correlation effects are significant. The resulting dataset provides accurate atomic parameters essential for plasma diagnostics, impurity transport modeling, and spectral analysis in magnetic confinement fusion devices such as ITER.