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CHVCs: Galactic Building Blocks at z = 0

Robert Braun·W. Butler Burton
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Abstract

A distinct sub-class of anomalous velocity HI emission features has emerged from recent high quality surveys of the Local Group environment, namely the compact high velocity clouds (CHVCs). A program of high-resolution imaging with the Westerbork array and the Arecibo telescope has begun to provide many insights into the nature of these objects. Elongated core components with a velocity gradient consistent with rotation (V_Rot ~ 15 km/s) are seen in many objects. Comparison of volume and column densities has allowed the first distance estimates to be made (600+/-300 kpc). The objects appear to be strongly dark-matter dominated with dark-to-gas mass ratios of 30-50 implied if the typical distance is 700 kpc.

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Robert Braun, W. Butler Burton. 2000-02-16. CHVCs: Galactic Building Blocks at z = 0. https://arxiv.org/abs/astro-ph/0002320

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