Ionized Gas in the Smith Cloud
Astrophysics of Galaxies
2012-09-26 v1
Abstract
We present WHAM observations of Halpha, [N II], and [S II] in the Smith Cloud. A map of Halpha emission from the cloud shows ionized gas coincident with the brightest H I emission, but nearly-as-bright Halpha in some regions with faint H I. The ionized mass of the cloud is at least as large as the neutral mass, > 10^6 M_sun. Ionized gas in the core of the Smith Cloud has an electron temperature 6000 K < T < 16000 K. The observed ratio [N II] / Halpha = 0.39 \pm 0.09 shows that the cloud has a non-primordial nitrogen abundance, 0.1 - 1 times solar.
Cite
@article{arxiv.0901.0712,
title = {Ionized Gas in the Smith Cloud},
author = {Alex S. Hill and L. Matthew Haffner and Ronald J. Reynolds},
journal= {arXiv preprint arXiv:0901.0712},
year = {2012}
}
Comments
4 pages, 2 figures. To appear in the proceedings of "The Role of Disk-Halo Interaction in Galaxy Evolution: Outflow vs Infall?", EAS Publication Series