GBT26A-579

Characterizing gas reservoirs feeding planet-forming disks

Abstract

The traditional picture of star formation suggests that as a protostar evolves to the Class II stage - i.e., its envelope disperses - a circumstellar disk is left behind that evolves in isolation to form a planetary system. However, these Class II systems are still moving within large-scale molecular clouds. Simulations and recent observations suggest that many Class II disks continue to accrete material from surrounding molecular clouds through infalling streamers. This late-stage infall of material can strongly influence disk evolution by altering its physical and chemical properties. Existing interferometric observations resolve the streamers but filter out the larger-scale gas reservoirs that feed them, leaving the total available mass and the viability of sustained accretion poorly constrained. We propose X-band Green Bank Telescope observations targeting HC3N and HC5N toward the well-studied Class II systems AB Aur and SU Aur, both of which show clear evidence of active infall. These observations will allow us to measure the mass of the large-scale reservoirs supplying the streamers and, therefore, provide important constraints on the overall impact of streamers on the evolution of planet-forming disks.

Investigators

Name	Institution
Samantha Scibelli	National Radio Astronomy Observatory; Arizona, University of
Aashish Gupta *	Virginia, University of
Lauren Cleeves	Virginia, University of
CI XUE	Massachusetts Institute of Technology
Claudia Toci	Milano, Università degli Studi di

* indicates the PI