X-ray Flaring Events Drive Non-Equilibrium Chemistry in Protoplanetary Disks

Historically, the chemical evolution of protoplanetary disks has been modeled with relatively constant physical conditions over the disk lifetime (millions of years). However, young, pre-main sequence T-Tauri stars commonly undergo X-ray flaring events that increase the X-ray ionization rate throughout the surrounding protoplanetary disk over short timescales (days). We find that this time variable stellar X-ray luminosity can impact the chemical evolution of the disk on both a day to day basis (e.g. HCO⁺ and H₂O) and can also result in the long-term net enhancement or destruction of some biologically relevant species, such as HCN and CS due to their cumulative impact. We will present recent chemical modeling results on the impact of individual and aggregate flaring events on chemical evolution in a protoplanetary disk and their potential for observability. This work suggests that the chemistry in planet forming regions may be far more dynamic than previously assumed.