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Extra-planar H Ι in the inner Milky Way
conference contribution
posted on 2023-05-23, 17:56 authored by Lockman, FJ, Pidopryhora, YThe extra-planar HI in the inner parts of the Milky Way has been discovered to contain numerous cloud-like structures when observed in the 21 cm line with the Green Bank Telescope. These halo clouds have motions consistent with Galactic rotation and do not seem to be related to the classic high-velocity clouds. They are found to distances >1 kpc from the plane and can contain hundreds of M☉ of HI. Spectra of many of the halo clouds show evidence of coexisting cool and warm HI phases. A preliminary high-resolution study of one of the clouds suggests that it consists of a di®use envelope and a few dense cores, with a peak NH I reaching 4 X 1020 cm-2. The clouds are often organized into larger structures, one example of which was discovered near ζ = 35° rising higher than 2 kpc above the Galactic plane. New observations should answer some fundamental questions about the nature of these clouds.
History
Publication title
Proceedings of the Astronomical Society of the Pacific Conference 2004Volume
331Editors
R BraunPagination
59-66Department/School
School of Natural SciencesPublisher
Astronomical Society of the PacificPlace of publication
San Francisco, USAEvent title
Astronomical Society of the Pacific Conference 2004Event Venue
Dwingeloo, The NetherlandsDate of Event (Start Date)
2004-06-07Date of Event (End Date)
2004-06-11Repository Status
- Restricted