Photoionization and Electron–Ion Recombination in Astrophysical Plasmas

Photoionization and its inverse, electron–ion recombination, are key processes that influence many astrophysical plasmas (and gasses), the diagnostics we use to analyze plasmas. In this review provide a brief overview of importance photoionization recombination in astrophysics. We highlight how data needed for spectral analyses, required accuracy, varies considerably different environments. then discuss processes, highlighting resonances their cross-sections. Next radiative low high temperature dielectronic recombination. The possible suppression (LTDR) (HTDR) due radiation field densities is discussed. Finally few examples processes.