The Fe Kα line, or iron Kα line, is often used in astronomical research to understand the physical composition of astronomical objects. This line is produced when a K-shell electron of an iron ion in the photosphere—the gas on the stellar surface—is ejected by an external process, and has been detected in X-ray spectra of solar and stellar flares. Yet the dominant mechanism behind this ionization process has remained an open question for many years.
