Abstract
Recent observations have shown that star-forming galaxies like our own Milky Way evolve kinematically into ordered thin disks over the last ∼8 billion years since z = 1.2, undergoing a process of "disk settling." For the first time, we study the kinematic evolution of a suite of four state of the art "zoom in" hydrodynamic simulations of galaxy formation and evolution in a fully cosmological context and compare with these observations. Until now, robust measurements of the internal kinematics of simulated galaxies were lacking because the simulations suffered from low resolution, overproduction of stars, and overly massive bulges. The current generation of simulations has made great progress in overcoming these difficulties and is ready for a kinematic analysis. We show that simulated galaxies follow the same kinematic trends as real galaxies: they progressively decrease in disordered motions (σg ) and increase in ordered rotation (V rot) with time. The slopes of the relations between both σg and Vrot with redshift are consistent between the simulations and the observations. In addition, the morphologies of the simulated galaxies become less disturbed with time, also consistent with observations. This match between the simulated and observed trends is a significant success for the current generation of simulations, and a first step in determining the physical processes behind disk settling.
Original language | English (US) |
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Article number | 89 |
Journal | Astrophysical Journal |
Volume | 790 |
Issue number | 2 |
DOIs | |
State | Published - Aug 1 2014 |
Keywords
- galaxies: evolution
- galaxies: formation
- galaxies: fundamental parameters
- galaxies: kinematics and dynamics
- galaxies: spiral
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science