Vorschau

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Abstract

The big picture of the planet formation scenario is sought by understanding the interplay between the gas and dust dynamics in protoplanetary disks. In particular, the gas dynamics in accretion disks have been carefully studied in a purely hydrodynamical set up where the vertical shear instability (VSI) play a major role in the transport of the angular momentum and turbulence throughout the disk. Though, it is very difficult to directly measure the angular momentum transport, mechanisms that affect it are the launch of magneto centrifugal winds (MHD winds), outflows, and the launch of thermal photoevaporative winds. One way to pin point these processes is by identifying forbidden emissions lines in the disk spectrum and analyze their velocity components that are originating in highly ionized gas. The exact thermochemical conditions in active accreting disks that cause the emission of different forbidden emission lines is very challenging to determine. To understand such outflows, the wind launching mechanisms and their effects to the angular momentum transport require the knowledge of a full global picture of hydro- and thermal- dynamical configurations.

The work presented here covers a broad range of scenarios that are important for the evolution and dispersal of the protoplanetary disk. Our focus relies more on the dynamics and the thermo-chemistry conditions at the surface of the disk. We found that the VSI is active until the location of the wind base. The characteristic vertical velocity in this region is about a fraction of the sound speed. For the first time, we report small scale vortices appearing in VSI active disks which influence especially the dust evolution. From spectral and imaging observations obtained from the Multi-unit Spectroscopic Explorer (MUSE) instrument at the Very Large Telescope (VLT), high velocity components (HVCs; $>$100 km~s$^{-1}$) are detected at the inner parts of the disks as outflows/jets that are aligned within 1 degree with respect to the outer disk. With our current and upcoming global hydrodynamical models including thermochemistry and observations, we will reveal the detailed chemical and physical conditions of protoplanetary disks with active winds at the surface.