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arXiv · 1204.1133

Simulation of radiation driven wind from disc galaxies

Indranil Chattopadhyay·Mahavir Sharma·Biman B. Nath·Dongsu Ryu
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Abstract

We present 2-D hydrodynamic simulation of rotating galactic winds driven by radiation. We study the structure and dynamics of the cool and/or warm component($T \simeq 10^4$ K) 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 $\sim 5$ kpc in $\sim 37$ Myr for typical galactic parameters. The outflow speed increases rapidly with the disc Eddington parameter $Γ_0(=κI/(2 c G Σ)$) for $Γ_0 \ge 1.5$. We find that the rotation speed of the outflowing gas is $\lesssim 100$ km s$^{-1}$. The wind is confined in a cone which mostly consist of low angular momentum gas lifted from the central region.

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Indranil Chattopadhyay, Mahavir Sharma, Biman B. Nath, Dongsu Ryu. 2012-04-05. Simulation of radiation driven wind from disc galaxies. https://doi.org/10.1111/j.1365-2966.2012.21027.x

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