Dark gas : a new possible link between low and high-energy phenomena
Dark gas : a new possible link between low and high-energy phenomena
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暗气体：低能和高能现象之间新的可能联系
DOI：
10.1017/s1743921312009477
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
鳥居和史
中科院分区：
文献类型：
--
作者：
Nara;T.;森島邦博;鳥居和史
对γ射线和亚毫米辐射的银河系尺度研究表明，在CO或HI中都检测不到大量的中性星际介质（Grenier et al. 2005; Ade et al. 2011）。这种成分被称为“暗气体”。在这里，我们认为没有分子的冷而致密的原子气体是暗气体的原因。这一解释得到了最近在SNR RX J1713.7-3946中发现的对应于TeV γ射线壳层的冷HI气体的支持（Fukui et al. 2011）。这样的HI气体在通常的光学薄HI发射假设下是无法识别的，但通过考虑光学厚HI的仔细分析是可以识别的。这种HI气体的典型柱密度是1021 cm−2的几倍，也被认为是视觉消光。
Galactic-scale studies of γ-rays and sub-mm radiation suggest that a significant amount of neutral interstellar medium is not detectable either in CO or HI (Grenier et al. 2005; Ade et al. 2011). This component is called “dark gas”. Here we argue that cool and dense atomic gas without molecules is responsible for the dark gas. This interpretation is supported by a recent finding of cool HI gas corresponding to the TeV γ-ray shell in the SNR RX J1713.7-3946 (Fukui et al. 2011). Such HI gas is not recognized under a usual assumption of optically thin HI emission but is identified by a careful analysis considering optically thick HI. The typical column density of such HI gas is a few times 1021 cm−2 and is also identified as visual extinction.