Work

Evolving Gravitationally Unstable Disks Over Cosmic Time: Implications for Thick Disk Formation

Year: 2012

Type: article

Abstract: Observations of disk galaxies at z ∼ 2 have demonstrated that turbulence driven by gravitational instability can dominate the energetics of the disk. We present a one-dimensional simulation code, which we have made publicly available, that economically evolves these galaxies from z ∼ 2 to z ∼ 0 on a single CPU in a matter of minutes, tracking column density, metallicity, and velocity dispersions of gaseous and multiple stellar components. We include an H 2 -regulated star formation law and the effects of stellar heating by transient spiral structure. We use this code to demonstrate a possible explanation for the existence of a thin and thick disk stellar population and the age–velocity-dispersion correlation of stars in the solar neighborhood: the high velocity dispersion of gas in disks at z ∼ 2 decreases along with the cosmological accretion rate, while at lower redshift the dynamically colder gas forms the low velocity dispersion stars of the thin disk.

Source: The Astrophysical Journal

DOI: 10.1088/0004-637x/754/1/48

Authors: John Forbes, Mark Krumholz, Andreas Burkert

Institutions: University of California, Santa Cruz, Max Planck Institute for Extraterrestrial Physics, Ludwig-Maximilians-Universität München

Language: English

Topic: Galaxies: Formation, Evolution, Phenomena

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: bronze

Funders: National Science Foundation, National Aeronautics and Space Administration, Alfred P. Sloan Foundation

Awards: THE FORMATION OF HIGH-MASS STARS AND THEIR FEEDBACK EFFECTS THE FORMATION OF MASSIVE STARS REMAINS ONE OF THE MOST SIGNIFICANT UNSOLVED PROBLEMS IN, CAREER: Toward a Predictive Theory of Star Formation, G6671297155