PF-02-0004

Systematic search for late-stage infall of material onto Class II disks

Aashish Gupta, Anna Miotello, Carlo Felice Manara, Jonathan P. Williams, Stefano Facchini, Giacomo Beccari, Til Birnstiel, Christian Ginski, Alvaro Hacar, Michael Kuffmeier, Leonardo Testi, Lukasz Tychoniec, Hsi-Wei Yen

It is generally assumed that Class II sources evolve independently of their surroundings, but many of them are still located near their parent clouds and may continue to interact with them. This may result in late accretion of material onto the disk that can significantly influence disk evolution and planet formation. To systematically study this process, we examined whether proximity to reflection nebulae could be used as a criterion for identifying Class II sources that may be experiencing late-infall. Our results suggest that at least five Class II objects associated with a prominent reflection nebula, and for which adequate ALMA observations are available, have spirals or stream-like structures which may be due to late-infall. Moreover, a significant fraction of Class II disks in nearby star-forming regions may be undergoing this phenomenon. Finally, we explore ways to quantify the dynamics of infalling streamers to better understand their impact on the protoplanetary disks.