Doctorant : Gaylor WAFFLARD-HERNANDEZ
Directeur de thèse : Clément BARUTEAU
Date début : Janvier 2018
Groupe thématique : PS2E
Over the last few years, multi-wavelength observations have underlined that the gas and dust of protoplanetary disks may have very different spatial distributions, more especially for the large dust particles (dust with a size of order a millimetre and beyond). These distributions are very diverse (spiral waves, annular gaps, horseshoe-shaped asymmetries…) and are often interpreted as signatures of the presence of (hidden) planets. These observations stress the need for a better understanding of how disk-planet interactions generally, and planetary migration more specifically, impact the dust’s thermal emission in protoplanetary disks. This is the aim of this PhD thesis.
The gravitational interaction between planets and the protoplanetary disk gas changes rapidly the distance between the planets and the star. This is known as planetary migration. Many studies have examined how the direction and speed of planetary migration depend on the planet’s mass and the physical properties of the disk gas, with the aim to explain the orbital properties of exoplanets. Dust is most often discarded in this kind of studies because its mass content is much smaller than that of the gas and it should therefore have a negligible impact on planetary migration. The subject of this PhD thesis is to investigate the dynamics and the thermal emission of dust in a protoplanetary disk where one or several planets form and migrate.
In this PhD project I perform hydrodynamical simulations modelling both the gas and dust of a protoplanetary disk where one or several planets are formed. I am using the public hydrodynamical code FARGO, which has been co-developed by my PhD supervisor Clément Baruteau. These simulations allow me to predict the spatial distribution of dust from a few microns to a few centimetres in size for several regimes of planetary migration, by varying the planets mass and the physical properties of the disk. Then I use the results of simulations to compute synthetic images of the dust’s continuum emission as it would be observed in the radio by interferometric imaging, with ALMA or NOEMA for example. For this purpose I plan to use the public radiative transfer code RADMC-3D.