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arXiv · 0711.3478

Resolving Gas Dynamics in the Circumnuclear Region of a Disk Galaxy in a Cosmological Simulation

Robyn Levine·Nickolay Y. Gnedin·Andrew J. S. Hamilton·Andrey V. Kravtsov
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Abstract

Using a hydrodynamic adaptive mesh refinement code, we simulate the growth and evolution of a galaxy, which could potentially host a supermassive black hole, within a cosmological volume. Reaching a dynamical range in excess of 10 million, the simulation follows the evolution of the gas structure from super-galactic scales all the way down to the outer edge of the accretion disk. Here, we focus on global instabilities in the self-gravitating, cold, turbulence-supported, molecular gas disk at the center of the model galaxy, which provide a natural mechanism for angular momentum transport down to sub-pc scales. The gas density profile follows a power-law scaling as r^-8/3, consistent with an analytic description of turbulence in a quasi-stationary circumnuclear disk. We analyze the properties of the disk which contribute to the instabilities, and investigate the significance of instability for the galaxy's evolution and the growth of a supermassive black hole at the center.

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Robyn Levine, Nickolay Y. Gnedin, Andrew J. S. Hamilton, Andrey V. Kravtsov. 2007-11-21. Resolving Gas Dynamics in the Circumnuclear Region of a Disk Galaxy in a Cosmological Simulation. https://doi.org/10.1086/529064

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