Planet formation

Context

New observational facilities are redefining our ideas on discs:

(1) ALMA/SPHERE are producing spectacular images of individual discs, revealing an amazing complexity in morphology. ALMA also opened the investigation of the physical, chemical and dynamical properties of gas: we can now routinely spatially resolve a wide variety of molecular species, that give us direct information on temperature gradient and surface density of the gas. At the same time, NIR high contrast can detect very young massive planets in the disc gaps and study their immediate environment.

Protoplanetary disks as observed by ALMA

(2) Another key aspect regards the spectroscopic characterisation of young stellar objects with protoplanetary discs, based on VLT-XShooter data (complemented by VLT-CRIRES and JWST) that we have and are acquiring. This analysis will provide information on the stellar and accretion properties, as well as on the properties of the winds and jets through forbidden line emission.

Goals

Hydrodynamical simulation of a disc torn into two disconnected rings by a central binary (left), synthetic ALMA dust continuum emission (middle), and synthetic scattered light infrared emission, with prominent shadows (right) - Facchini, Juhasz & Lodato (2018)

- To expand the detailed study of individual systems,

- to derive a consistent and robust scenario for these very early phases of formation of substellar companions from circumstellar discs,

- to prepare dedicated SKA campaigns, and

- to obtain statistically significant samples to be compared with models of planet formation.

Synergies

Our group naturally provides strong synergies between the different expertises required for a proper understanding of the various components of protoplanetary discs. We include theorists, both for the early, gas rich phase of disc evolution (OA Brera - UniMi) and for the later phases dominated by solids (IAPS), observers at sub-millimeter wavelengths (OA Arcetri node), experts in planet detection in young discs (OA Padova), and in observations of accretion/jets and outbursting YSOs (OA Arcetri, OA Roma, OA Napoli).