Speaker
Description
The large scale crescent shape structures detected in protoplanetary disks have sometimes been interpreted as vortices. Vortices are of particular interest to understand planet formation as they are known to concentrate dust and could participate to planetesimal formation. We study the multiple fingerprints of such large Rossby vortices and propose observational predictions to test the if these crescents could be interpreted as vortices.
We performed 2D hydro-simulations where a vortex forms at the edge of a gas depleted region. We derived idealized line-of-sight velocity maps, varying orientation relative to the observer. The signal of interest, as a small perturbation to the dominant axisymetric component in velocity, may be isolated in observational data using a proxy for the dominant quasi-Keplerian velocity. We propose that the velocity curve on the observational major axis be such a proxy. Applying our method to the disk around HD 142527 as a study case, we predict line-of-sight velocities scarcely detectable by currently available facilities. We show that corresponding spirals patterns can also be detected with similar spectral resolutions.
