Disk Chemical Structures at Planet-forming Scales

Charles Law

Tuesday December 1st, 14:30

Planets form and obtain their compositions in dust- and gas-rich disks around young stars. This process is intimately connected to the spatial arrangement of disk material, but only recently has it become clear that disks are not always smooth in either their dust or gas distributions. Dust substructure at the au-to-10 au scale is ubiquitous, as revealed by the DSHARP program, but far fewer observations have probed gas substructure at similar scales. As a result, it is not known whether dust and chemical substructures are linked on such scales, and the causal relationship between dust and molecular distributions remains largely unexplored. To address this, I will present initial results from the The Molecules with ALMA at Planet-forming Scales (MAPS) Large Program, which explores radial and vertical disk chemical structures at 10 au scales in five disks where dust substructure is detected and planet formation appears to be ongoing. A wide diversity of line morphologies, including rings, gaps, and emission plateaus, is observed with substructures occurring at almost any radius in which line emission is detected. I will discuss how these chemical substructures correlate with one another, with dust gaps, rings, and outer edges, and with expected snowline locations. I will pay special attention to the inner 50 au of disks, and other regions where there are signs of ongoing planet formation, and provide some first conclusions about what MAPS is teaching us about the chemistry of planet formation.