Gravitational instability in astrophysical gas disks is a a ubiquitous phenomenon with crucial implications on structure formation inside disks as well as on their evolution at both short and long timescales. The most extreme manifestation of it, disk fragmentation, could lead to the formation of a variety of astrophysical objects, from stellar companions and gas giant planets in protostellar and protoplanetary disks to Giant Molecular Clouds (GMCs) in normal disk galaxies, to forming giant clumps in massive high-redshift galaxies. Fragmentation could occur also in the outer fringes of AGN accretion disks, and might be responsible for the formation of one of the population of stars at the Galactic Center. Gravitational instability and collapse can also be seeded in two-fluid disks leading, for example, to the rapid formation of planetesimals in protoplanetary disks.
Angular momentum and mass are efficiently transported in gravitationally unstable disks, which leads to global evolution even in the absence of fragmentation, often leading to mass growth of a central gravitating object such a star in a protostellar disk or a massive black hole at the center of galaxies. Different communities are working on these diverse topics, often using similar approaches and computational methods to study gravitational instability, an inherently nonlinear phenomenon. However such communities have very little interaction as they deal with very different astrophysical scales, from cosmological to planetary, despite the common background physics involved. With this workshop we aim at bringing together worldwide experts of these various communities, especially theoreticians and computational astrophysicists, to assess and discuss the latest understanding of gravitational instability and, in particular, disk fragmentation.
We will also have a limited number of observational astronomers who are leading efforts to find evidences of such phenomena in nature, and who have been involved in recent efforts with theorists to develop mock observations of simulations. We will focus on the most important open issues, such as the effect of radiative physics and energy feedback processes, the onset of gravitoturbulence and its back reaction on instability, the role of matter infall and tidal perturbations in disk instability. We will foster interaction between the various communities, setting concrete goals such as a new international code comparison project that should settle the level of agreement and disagreement between various computational techniques in modeling disk instability and fragmentation.
Organisers: L. Mayer, A. Burkert, R. Helled, F. Meru
Sunday, July 16, 2017 at 6 p.m. welcome drink with refreshments and opening of registrations at Sexten Primary School - Via Panorama 6 - Sexten
The meeting will begin on Monday July 17th at 9.00 and will end within Friday 21th July at 13.00.
Within the registration form you can book your transfer from Venice to Sexten on 16th July.
Getting here Please refer to: logistics
Registration form (transfer booking included)