EAS Publications Series
Volume 56, 2012The Role of the Disk-Halo Interaction in Galaxy Evolution: Outflow vs. Infall?
|Page(s)||319 - 322|
|Section||The Active Disk-Halo Connection: Infall vs. Outflows|
|Published online||17 September 2012|
Miguel A. de Avillez (ed)
EAS Publications Series, 56 (2012) 319–322
Ionization of Infalling Gas
1 Department of Astronomy, University of Wisconsin , Madison, WI, USA
2 School of Physics, The University of Sydney, NSW 2006, Australia
Hα emission from neutral halo clouds probes the radiation and hydrodynamic conditions in the halo. Armed with such measurements, we can explore how radiation escapes from the Galactic plane and how infalling gas can survive a trip through the halo. The Wisconsin H-Alpha Mapper (WHAM) is one of the most sensitive instruments for detecting and mapping optical emission from the ISM. Here, we present recent results exploring the ionization of two infallling high-velocity complexes. First, we report on our progress mapping Hα emission covering the full extent of Complex A. Intensities are faint (100 mR; EM 0.2pccm−6) but correlate on the sky and in velocity with 21-cm emission. Second, we explore the ionized component of some Anti-Center Complex clouds studied by Peek et al. (2007) that show dynamic shaping from interaction with the Galactic halo.
© EAS, EDP Sciences, 2012