Abstract:
Turbulence is a key physical process expected to stir the planet-forming material and act as an effective viscosity, aiding the evolution of protoplanetary disks. However, detection of turbulent motion has been scarce in the past years. This work presents an observationally motivated methodology that takes advantage of the high spatial and spectral resolution of ALMA observations to measure turbulence through molecular line broadening.
By tracing distinct regions of the protoplanetary system using specific molecular tracers, we are able to resolve vertical and radial variations in turbulent motions, obtaining the first insights into the physical instabilities that may be driving turbulence in these disks. Our work presents results from specific disks, such as IM Lup and a broad sample from the DECO ALMA Large Program, showing a variety of turbulent levels traced by CN, N2H+ and other optically thin lines. Overall, this work presents the first non-parametric and observationally motivated resolved measurements on turbulence from an observational perspective.
