From dust grains to planets : How the observations of dust asymmetries and spirals in protoplanetary disks can constrain the planet assembly ?

Séminaire IPAG de Yann Boehler (IPAG), jeudi 7 février 2019 à 11h00, salle Manuel Forestini

During the last 2-5 years, the advent of new observational facilities such as the Atacama Large Millimeter Array (ALMA), or the Sphere instrument on the Very Large Telescope (VLT), has drastically changed our vision of protoplanetary disks. Thanks to their very high spatial resolution and sensitivity, these instruments have shown that protoplanetary disks are not homogeneous structures as hypothesized before, but present numerous structures in the dust emission : azimuthal asymmetries, spirals and rings.

In this talk, I will summarize major results and will discuss the last advances in our understanding of dust asymmetries and spirals. I will address how the presence of dust asymmetries is linked to the formation of planetary embryos, and particularly the constraints that our observations on HD 142527 and MWC 758 have added to this scenario. However, planets might have formed also early on in disks and then could be visible through the presence of rings and spirals. I will discuss particularly the observations of spirals and if their presence can really be connected to planets or, on the contrary, be linked to gravitational instabilities and stellar flybys. I will finally propose future guidelines to make progress in the field.