Properties of the thinnest cold HI clouds in the diffuse interstellar medium
Abstract
We have obtained deep HI observations in the direction of 22 continuum sources without previously detected cold neutral medium (CNM). 18 CNM clouds were detected with the typical HI column density of cm. Our surprisingly high detection rate suggests that clouds with low HI column densities are quite common in the interstellar medium. These clouds appear to represent an extension of the traditional CNM cloud population, yet have sizes in hundreds to thousands of AUs. We present properties of the newly-detected CNM sample, and discuss several theoretical avenues important for understanding the production mechanisms of these clouds.
Cite
@article{arxiv.astro-ph/0610388,
title = {Properties of the thinnest cold HI clouds in the diffuse interstellar medium},
author = {Snezana Stanimirovic and Carl Heiles and Nissim Kanekar},
journal= {arXiv preprint arXiv:astro-ph/0610388},
year = {2007}
}
Comments
to be published in the proceedings of the meeting on "Small Ionized and Neutral Structures in the Diffuse Interstellar Medium" (ASP Conference Series)