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Tiny-Scale Atomic Structure and the Cold Neutral Medium--Review and Recap

Carl Heiles
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Abstract

Almost a decade ago I wrote an article with the same title as this. It focused on the physical properties of the Tiny-Scale Atomic Structure (TSAS) as discrete structures of the Cold Neutral Medium (CNM). To be observable, tiny discrete structures that don't grossly violate pressure equilibrium need two attributes: low temperatures and geometrical anisotropy. Here I update that article. I discuss thermal and pressure equilibrium, ionization, optical lines, H_2 abundance, and evaporation.

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Carl Heiles. 2007-01-22. Tiny-Scale Atomic Structure and the Cold Neutral Medium--Review and Recap. https://arxiv.org/abs/astro-ph/0701625

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