Neutral hydrogen in galactic fountains
Abstract
Simulations of an isolated Milky Way-like galaxy, in which supernovae power a galactic fountain, reproduce the observed velocity and 21cm brightness statistics of galactic neutral hydrogen (HI). The simulated galaxy consists of a thin HI disk, similar in extent and brightness to that observed in the Milky Way, and extra-planar neutral gas at a range of velocities due to the galactic fountain. Mock observations of the neutral gas resemble the HI flux measurements from the Leiden-Argentine-Bonn (LAB) HI, survey, including a high-velocity tail which matches well with observations of high-velocity clouds. The simulated high-velocity clouds are typically found close to the galactic disk, with a typical line-of-sight distance of 13kpc from observers on the solar circle. The fountain efficiently cycles matter from the centre of the galaxy to its outskirts at a rate of around 0.5 M_sun/yr
Cite
@article{arxiv.0708.0221,
title = {Neutral hydrogen in galactic fountains},
author = {C. M. Booth and Tom Theuns},
journal= {arXiv preprint arXiv:0708.0221},
year = {2012}
}
Comments
5 pages, 5 figures. Accepted for publication in MNRAS letters