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Effelsberg HI Survey of Compact High-Velocity Clouds

T. Westmeier·C. Bruens·J. Kerp
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Abstract

We studied 11 compact high-velocity clouds (CHVCs) in the 21-cm line emission of neutral hydrogen with the 100-m telescope in Effelsberg. We find that most of our CHVCs are not spherically-symmetric as we would expect in case of a non-interacting, intergalactic population. Instead, many CHVCs reveal a complex morphology suggesting that they are disturbed by ram-pressure interaction with an ambient medium. Thus, CHVCs are presumably located in the neighborhood of the Milky Way instead of being spread across the entire Local Group.

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T. Westmeier, C. Bruens, J. Kerp. 2003-10-09. Effelsberg HI Survey of Compact High-Velocity Clouds. https://arxiv.org/abs/astro-ph/0310247

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