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Tiny HI Clouds in the Local ISM

Robert Braun·Nissim Kanekar
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Abstract

Very sensitive HI absorption spectra (tau RMS about 10^-4 over 1 km/s) toward high latitude QSOs have revealed a population of tiny discrete features in the diffuse ISM with peak tau of 0.1 - 2% and core line-widths corresponding to temperatures as low as 20 K. Imaging detections confirm linear dimensions of a few 1000 AU. We suggest these structures may be formed by the stellar winds of intermediate mass stars. A more speculative origin might involve molecular "dark matter".

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Robert Braun, Nissim Kanekar. 2004-09-17. Tiny HI Clouds in the Local ISM. https://doi.org/10.1007/978-1-4020-3407-7_58

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