7 papers
H-alpha Distance Constraints for High-Velocity Clouds in the Galactic Halo
J. Bland-Hawthorn, P. R. Maloney
We present some developments in determining H-alpha distances to high-velocity clouds (HVCs) in the Galactic halo. Until recently, it was difficult to assess the nature and origin…
The Impact of Star Formation and Active Nuclei on the Interstellar Medium in Ultraluminous Infrared Galaxies
Philip R. Maloney
The energy input into the interstellar medium in Ultraluminous Infrared Galaxies (ULIRGs) is enormous, regardless of the nature of the power source. I discuss some of the major con…
Warm Gas and Ionizing Photons in the Local Group
Philip R. Maloney, J. Bland-Hawthorn
We investigate how much warm (T \sim 10^6 K) gas may exist in a Local Group corona, and, in particular, whether such a corona could be detected indirectly through its ionizing radi…
Ionizing Photon Sources within the Local Group
Philip R. Maloney, J. Bland-Hawthorn
We review the possible sources of ionizing photons within the Local Group. Throughout most of the LG volume, the cosmic background radiation will dominate, but locally (e.g., withi…
Physical Conditions in Obscuring Tori and Molecular Accretion Disks, and Are They Really the Same Thing?
Philip R. Maloney
The nature of the obscuring material in active galactic nuclei is still uncertain. Although some sources, such as Cygnus A, show evidence for a geometrically thick ``torus'' as ori…
The Galactic Halo Ionizing Field
J. Bland-Hawthorn, P. R. Maloney
There has been much debate in recent decades as to what fraction of ionizing photons from star forming regions in the Galactic disk escape into the halo. The recent detection of th…