Seminario DAS: Vertical stratification of molecules as a probe for protoplanetary disk conditions

Speaker: Dr. Teresa Paneque-Carreño
Affiliation: University of Michigan

Abstract: ALMA observations of moderately inclined protoplanetary disks at sufficient resolution allow us to directly trace the emission location of various molecules in 3D. Through this innovative analysis it is possible to study the disk structure azimuthally, radially and vertically. In particular, the study of molecules linked to temperature, density and radiation conditions can be used to probe the disk physical properties.

This work presents observational results for the vertical distribution of CO isotopologues, HCN, CN, H2CO, HCO+, C2H in a sample of disks. In some cases the CO emission surface shows perturbations that are correlated with gaps in the millimeter continuum and kinematical features. We propose that the vertical distribution of CO may also be a direct probe for total disk mass and carbon depletion, while other tracers, such as CN and C2H may be used to measure turbulence in the upper disk. Overall, this approach offers key observables to compare with thermochemical models and directly relate the vertically extended gaseous reservoir to the planet-forming conditions.