Relaxed-ae: A fast, new publicly-available atmospheric escape code with metals and X-rays

Throughout their lives, short period exoplanets (< 100 days) are strongly irradiated by their host stars. Especially in the first few hundred megayears, photoionization by the young hot stars’ strong XUV fluxes can drive transonic winds that outflow from these planets. The mass loss histories of these planets are essential to understanding the architectures of these extreme solar systems; however, mass loss rates are not directly observable: they can only be inferred from models. To that end, we present, relaxed-ae a publically-available1D, multifrequency (thru to X-ray), multispecies, non-time-evolving, Parker Wind photoevaporation relaxation code based on Murray-Clay et al. (2009). The speed and reliability of the tool have allowed used in a number of investigations including: exploring the impact of metallicity on mass loss rates; simulating observability of metastable-He, Lyα, and metal lines in outflows; performing retrievals; investigating the mystery of unusually large X-ray transits; determining whether photoevaporation can reproduce both the period-radius valley and the Neptune desert in a population synthesis; and much more.