# Comment on "Electron impact excitation and ionization cross section of tungsten ions, W$^{44+}$" by El-Maaref et al. [J. Quant. Spectrosc. Radiat. Transfer 2019, 224:147]

## TL;DR

This paper critically evaluates and disputes the accuracy of previously published electron impact excitation data for tungsten ions, demonstrating that the earlier results are significantly underestimated and unreliable.

## Contribution

The authors provide independent calculations showing that prior collision strength results for W$^{44+}$ are vastly underestimated, challenging the validity of the original data.

## Key findings

- Previous collision strengths are underestimated by over two orders of magnitude.
- The new calculations suggest the need to revise atomic data for tungsten ions.
- The paper highlights the importance of independent verification of atomic data.

## Abstract

In a recent paper, El-Maaref et al. [J. Quant. Spectrosc. Radiat. Transfer 2019, 224:147] have reported atomic data for Zn-like W~XLV. Their results are mainly for energy levels, radiative rates, collision strengths ($\Omega$) for electron impact excitation, and cross sections for ionization, but for only for a few levels/transitions, and in a very limited range of energy. For the calculations of $\Omega$ they have adopted the DARC code. In this comment, through our independent calculations, we demonstrate that their results for $\Omega$ are highly underestimated by over two orders of magnitude, and hence are totally unreliable.