  The interplay of kinetic electron physics and atomic processes in ultrashort
laser-plasma interactions provides a comprehensive understanding of electron
energy distribution's impact on plasma properties. Notably, non-equilibrium
electrons play a vital role in collisional ionization, influencing ionization
degrees and spectra. This paper introduces a computational model that
integrates the physics of kinetic electrons and atomic processes, utilizing a
Boltzmann equation for non-equilibrium electrons and a collisional-radiative
model for atomic state populations. The model is used to investigate the
influence of non-equilibrium electrons on collisional ionization rates and
their effect on population distribution, as demonstrated by L. Young et al.
(Nature, 2010). The study reveals significant non-equilibrium electron presence
during XFEL-matter interactions, profoundly affecting collisional ionization
rates in the gas plasma, thereby necessitating careful consideration of the
Collisional-Radiative (CR) model applied to such systems.
