Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK.
Science. 2013 Dec 13;342(6164):1343-5. doi: 10.1126/science.1243582.
Noble gas molecules have not hitherto been detected in space. From spectra obtained with the Herschel Space Observatory, we report the detection of emission in the 617.5- and 1234.6-gigahertz J = 1-0 and 2-1 rotational lines of (36)ArH(+) at several positions in the Crab Nebula, a supernova remnant known to contain both molecular hydrogen and regions of enhanced ionized argon emission. Argon-36 is believed to have originated from explosive nucleosynthesis in massive stars during core-collapse supernova events. Its detection in the Crab Nebula, the product of such a supernova event, confirms this expectation. The likely excitation mechanism for the observed (36)ArH(+) emission lines is electron collisions in partially ionized regions with electron densities of a few hundred per centimeter cubed.
迄今为止，尚未在太空中检测到稀有气体分子。我们利用赫歇尔太空天文台获得的光谱，报告了在蟹状星云的几个位置检测到（36）ArH（+）的 617.5 和 1234.6 千兆赫 J = 1-0 和 2-1 旋转线的发射，蟹状星云是已知同时含有分子氢和增强的电离氩发射区域的超新星遗迹。人们认为，氩-36 来源于大质量恒星在核心坍缩超新星事件中的爆炸核合成。它在蟹状星云（超新星事件的产物）中的检测证实了这一预期。观察到的（36）ArH（+）发射线的可能激发机制是部分电离区域中的电子碰撞，电子密度为每立方厘米几百个。
