1998/11/13 by Mark Walker, M. A. Walker, Walker, Mark +3
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9811209
7 pages, 1 figure, LaTeX (uses paspconf.sty) To appear in Proc. Stromlo Workshop on High Velocity Clouds (PASP)
arxiv created 1998/11/13 · openalex publication_date 1998/11/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present the germ of a new model for High Velocity Clouds, derived from the idea that the dark matter halo of our Galaxy is in the form of cold, planetary-mass gas clouds. In this picture HVCs arise as a result of disruptive collisions between dark matter clouds: high velocity atomic gas is a natural consequence of the dark halo kinematics, and is intimately associated with assembly of the visible Galaxy. Quasi-spherical halo models predict a broad 21 cm line background, together with a number of individually detectable, low-mass HVCs conforming to a particular velocity field. A halo model which incorporates satellite substructure -- after the fashion of the current paradigm of hierarchical structure formation -- includes both these components and, in addition, some massive HVCs. These latter HVCs are simply the wakes of the orbiting satellite halos, and each may have a mass up to 0.3% of the mass of the satellite.