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The critical velocity effect as a cause for the Hαemission from the Magellanic stream

C. Konz·H. Lesch·G. T. Birk·H. Wiechen
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Abstract

Observations show significant Hα-emissions in the Galactic halo near the edges of cold gas clouds of the Magellanic Stream. The source for the ionization of the cold gas is still a widely open question. In our paper we discuss the critical velocity effect as a possible explanation for the observed Hα-emission. The critical velocity effect can yield a fast ionization of cold gas if this neutral gas passes through a magnetized plasma under suitable conditions. We show that for parameters that are typical for the Magellanic Stream the critical velocity effect has to be considered as a possible ionization source of high relevance.

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C. Konz, H. Lesch, G. T. Birk, H. Wiechen. 2000-10-09. The critical velocity effect as a cause for the Hαemission from the Magellanic stream. https://doi.org/10.1086/318690

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