| The 2022 outburst of EX Lup - a first look at the disk with the VLT and the JWST |
| Ágnes Kóspál |
| Konkoly Observatory, CSFK, Hungary |
| EXor-type variables, named after the prototype EX Lupi, are observable examples of episodic accretion during star formation. In early 2022, EX Lupi unexpectedly went into outburst. Our photometric monitoring suggests that this event was much less violent than its extreme eruption in 2008, giving us the opportunity to study quantitatively for the first time the effects of a moderate accretion burst on the circumstellar disk. With this aim, we obtained new ALMA, VLTI/MATISSE, VLT/XSHOOTER, and James Webb Space Telescope data for EX Lup in 2022. In this talk, I will show preliminary results of our analysis of these data. With ALMA we detected a plethora of molecular lines both from complex organic molecules and from simpler species, with tantalizing signs of deviations from Keplerian rotation. Accretion tracers at optical and near-infrared wavelengths suggest that the accretion rate only increased by a factor of few. Nevertheless, MATISSE and JWST revealed that even such a moderate outburst could produce detectable amounts of crystalline silicates, which then disappeared very quickly. Our JWST spectrum shows the warm molecular content of the disk with unprecedented details, from molecules such as CO, H2O, HCN, CO2, and C2H2. EX Lup is a good proxy for the proto-Sun and by studying its outbursts, we might infer what could have happened during the early evolution of the Solar System as well, including chemical and mineralogical effects on the material available for planet formation. |