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The Hydrogen Clouds in the Galactic Halo

Published online by Cambridge University Press:  26 May 2016

Felix J. Lockman
Felix J. Lockman*
Affiliation:
National Radio Astronomy Observatory, Green Bank WV, USA

Abstract

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New 21cm observations with the Green Bank Telescope show that a significant fraction of the HI in the inner Galaxy's halo ~ 1 kpc from the midplane exists in the form of discrete clouds. Some look very much like a Spitzer (1968) “standard” diffuse cloud but with their HI in two phases. They mark the transition between the neutral disk and the highly ionized halo. The dominant motion of the clouds is Galactic rotation, but some have random velocities of as much as 50 km s−1. They are part of the Galaxy and are not related to high-velocity clouds, yet their origin is obscure.

Type
Part 2. Origin
Information
Symposium - International Astronomical Union , Volume 217: Recycling Intergalactic and Interslettar Matter , 2004 , pp. 130 - 135
Copyright
Copyright © Astronomical Society of the Pacific 2004 

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