EAS Publications Series
Volume 56, 2012The Role of the Disk-Halo Interaction in Galaxy Evolution: Outflow vs. Infall?
|Page(s)||327 - 330|
|Section||The Active Disk-Halo Connection: Infall vs. Outflows|
|Published online||17 September 2012|
Miguel A. de Avillez (ed)
EAS Publications Series, 56 (2012) 327–330
Ionized gas in the Smith Cloud
Department of Astronomy, University of Wisconsin-Madison, Madison, WI, USA
We present WHAM observations of Hα, [N II], and [S II] in the Smith Cloud. A map of Hα emission from the cloud shows ionized gas coincident with the brightest H I emission, but nearly-as-bright Hα in some regions with faint H I. The ionized mass of the cloud is at least as large as the neutral mass, >106M⊙. Ionized gas in the core of the Smith Cloud has an electron temperature 6000 K < T < 16 000 K. The observed ratio [N II]/Hα = 0.39 ± 0.09 shows that the cloud has a non-primordial nitrogen abundance, 0.1 − 1× solar.
© EAS, EDP Sciences, 2012