Unveiling stellar aurorae

We investigate auroral emission lines in hot stars induced by irradiation, shedding light on the intricate interplay between magnetic fields and stellar winds. Employing the TLUSTY and SYNSPEC codes, we generate high-resolution synthetic spectra, which unveil potential infrared emission lines, notably He ii 69458 Å, observed across a range of effective temperatures (15 kK to 30 kK). Additionally, our analysis reveals the presence of infrared excess, indicative of underlying physical processes. Furthermore, we identify emission lines generated solely in the hottest model, attributed to NLTE effects rather than irradiation. These findings can contribute to our understanding of auroral phenomena in hot stars and underscore the significance of irradiation in shaping spectral features. Our research suggests promising avenues for further exploration in this field.