Simulation of radiation-driven winds from disc galaxies

Abstract

We present two-dimensional (2D) hydrodynamic simulation of rotating galactic winds driven by radiation. We study the structure and dynamics of the cool and/or warm component (T≃ 10 4K) which is mixed with dust. We have taken into account the total gravity of a galactic system that consists of a disc, a bulge and a dark matter halo. We find that the combined effect of gravity and radiation pressure from a realistic disc drives the gas away to a distance of ~5kpc in ~37 Myr for typical galactic parameters. The outflow speed increases rapidly with the disc Eddington parameter Γ 0(=κI/(2cGΣ)) for Γ 0≥ 1.5. We find that the rotation speed of the outflowing gas is ≲100kms -1. The wind is confined in a cone that mostly consists of low angular momentum gas lifted from the central region. ⓒ 2012 The Authors Monthly Notices of the Royal Astronomical Society.