Carbon monoxide in supernova 1987A
Carbon monoxide in supernova 1987A
复制标题
超新星 1987A 中的一氧化碳
作者：
J. Spyromilio;W. P. S. Meikle;R. C. M. Learner;D. A. Allen
1987 年 2 月 23 日爆炸的 SN1987A（参考文献 1-4）的红外光谱中一氧化碳的识别代表了首次在超新星中检测到分子。在英澳望远镜获得的红外光谱中，早在爆炸后第 112 天就在 2.3 µm 附近观察到了 CO 的第一次泛音发射，并且在所有后续光谱中都可以清楚地检测到。 4.6 µm 处的 CO 基本光谱支持这一鉴定。在这封信中，我们认为二氧化碳是超新星喷射物的一部分，并使用玻尔兹曼布居统计数据对第一泛音带进行了初步分析。该模型很好地再现了第 192 天和第 255 天获得的光谱，并暗示到第 255 天存在约 5 × 10-5 个太阳质量的 CO。到第 284 天，拟合效果不太好，因为其他物种的发射越来越突出，可能与玻尔兹曼分布的崩溃相结合。
The identification of carbon monoxide in the infrared spectra of SN1987A (refs 1–4), which exploded on 23 February 1987, represents the first-ever detection of a molecule in a supernova. In infrared spectra obtained with the Anglo-Australian Telescope, first overtone emission from CO was observed near 2.3 µm as early as day 112 after the explosion, and was clearly detectable in all subsequent spectra. Spectra of the CO fundamental at 4.6 µm support this identification. In this letter we argue that the CO forms part of the supernova ejecta, and present a preliminary analysis of the first overtone band using Boltzmann population statistics. The model reproduces well the spectra obtained on days 192 and 255 and implies the presence of about 5 × 10–5 solar masses of CO by day 255. By day 284 the fit is less good, owing to increasingly prominent emission from other species, possibly in combination with the breakdown of the Boltzmann distribution.