PI: Joan Najita, NOAO, firstname.lastname@example.org
Address: 950 N. Cherry Ave., Tucson, AZ 85719
CoI: John Carr, NRL
CoI: Colette Salyk, NOAO
CoI: Matt Richter, UC Davis
CoI: John Lacy, UT Austin
CoI: Curtis Dewitt, UC Davis
Title: The HCN/Water Ratio in Inner Disks: A Chemical \newline Signature of Planetesimal Formation?
Abstract: While core accretion is the foremost planet formation theory to date, there is little direct evidence whether planets form by core accretion or other means. To address this shortcoming, we propose to search nearby protoplanetary disks for chemical evidence of the formation of planetesimals. These objects are hallmarks of the core accretion process. In the proposed study, we will explore the trend we found between the \it Spitzer HCN/water flux ratio and submillimeter disk mass among T Tauri stars. This trend can be explained as a consequence of planetesimal formation if the HCN and water emission arise from the same region of the disk. To test the assumption that the HCN and water emission are cospatial, we will measure velocity-resolved line profiles of HCN and water in 4 T Tauri disks. If the HCN and water emission arise from the same range of disk radii, their line profiles will extend over the same range in velocity. The results of this study will provide direct insight into whether the HCN/water flux ratio of T Tauri disks is plausibly a chemical signpost of planetesimal formation.
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