English

New Temperatures of Diffuse Interstellar Gas: Thermally Unstable Gas

Astrophysics 2009-11-06 v1

Abstract

We present new Arecibo 21-cm line measurements of the temperatures of interstellar gas. Our temperatures for the Cold Neutral Medium (CNM) are significantly lower than previous single-dish results and in very good accord with theoretical models. For warm gas at T > 500 K, we find a significant fraction of gas (>47%) to lie in the thermally unstable region 500 ---> 5000 K; moreover, about 60% of all the neutral atomic gas has T > 500 K. Large amounts of thermally unstable gas are not allowed in theoretical models of the global interstellar medium.

Keywords

Cite

@article{arxiv.astro-ph/0103126,
  title  = {New Temperatures of Diffuse Interstellar Gas: Thermally Unstable Gas},
  author = {Carl Heiles},
  journal= {arXiv preprint arXiv:astro-ph/0103126},
  year   = {2009}
}

Comments

6 pages, 2 figures, accepted by ApJ Letters