New temperatures of diffuse interstellar gas: Thermally unstable gas

被引：75

作者：

Heiles, C ^{[1
]}

机构：

[1] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA

来源：

ASTROPHYSICAL JOURNAL | 2001年 / 551卷 / 01期

基金：

美国国家科学基金会;

关键词：

ISM : atoms; ISM : general; radio lines : ISM;

D O I：

10.1086/319844

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We present new Arecibo 21 cm line measurements of the temperatures of interstellar gas. Our temperatures for the cold neutral medium 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.

引用

页码：L105 / L108

页数：4

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