Periodic Reporting for period 4 - SACCRED (Structured ACCREtion Disks: initial conditions for planet formation in the time domain)
Periodo di rendicontazione: 2022-01-01 al 2023-06-30
Rings also appeared in our hydrodynamic disk simulations. Our modeling revealed the inward motion of these rings, providing a new type of explanation for the origin of outbursts (Fig.4). Measuring the timescales of brightening and fading of young stars may reveal much about the circumstellar structure and the physics of the eruptions. We monitored many FU Orionis-type stars to determine these parameters and were among the first to realize that the accretion of mass onto the protostar V346 Nor stopped for a short time a few years ago, posing difficult questions to outburst theories. We studied the effect of accretion outbursts on the disk from chemical and mineralogical points of view. We participated in numerical studies to predict what chemical reactions are triggered by the outburst heat and how the outbursts impact the size of the dust grains in the disk.
We conducted several studies of EX Lup, the prototype of one class of young eruptive stars. We combined observations with model simulations to follow up our previous result where we witnessed the crystallization of amorphous dust particles during the outburst of EX Lup in 2008. Now, we can demonstrate that the new crystals were transported outward. With the exceptional sensitivity of the James Webb Space Telescope, we successfully rediscovered the crystals in the cold parts of the disk. Some of these crystals might be mixed with ice and become parts of forming comets and planets. We also detected molecules that are essential ingredients for the development of life, such as carbon monoxide and water vapor (Fig.5).