Thirty Years of Cometary Spectroscopy from McDonald Observatory
Thirty Years of Cometary Spectroscopy from McDonald Observatory
复制标题
麦克唐纳天文台的彗星光谱三十年
DOI：
10.1016/j.icarus.2011.12.010
复制
发表时间：
2011
期刊：
影响因子：
3.2
通讯作者：
C. Gray
中科院分区：
文献类型：
--
作者：
A. Cochran;E. Barker;C. Gray
我们报告了从1980年到2008年在麦克唐纳天文台对130颗彗星进行的光谱调查的结果。其中一些彗星只在一个晚上被观测到，而另一些则被重复观测到。在这些彗星中，有20颗没有检测到分子。对于剩下的110颗彗星，至少有一次观测到了CN、OH、NH、C3、C2、CH和NH2分子的一些发射。我们使用Haser(Haser，L.[1957])将观察到的分子柱密度转换为产率。列日学院。天体物理学转载第394号)模型。我们定义了一个受限的彗星数据集，至少有三个晚上的观测。受限数据集由59颗彗星组成。我们使用生产率比率来研究数据中的趋势。我们发现了两类彗星：典型的和碳链耗尽的彗星。使用非常严格的枯竭彗星定义，要求C2和C3都枯竭，我们发现9%的受限数据集彗星都枯竭了。使用更宽松的定义，只要求C2低于阈值(类似于其他研究人员)，我们发现25%的彗星是枯竭的。在耗尽的彗星中，三分之二是木星家族彗星，三分之一是长周期彗星。37%的木星家族彗星枯竭，而18.5%的长周期彗星枯竭。我们将我们的结果与其他研究结果进行了比较，发现很好的一致性。
We report on the results of a spectroscopic survey of 130 comets that was conducted at McDonald Observatory from 1980 through 2008. Some of the comets were observed on only one night, while others were observed repeatedly. For 20 of these comets, no molecules were detected. For the remaining 110 comets, some emission from CN, OH, NH, C3, C2, CH, and NH2molecules were observed on at least one occasion. We converted the observed molecular column densities to production rates using a Haser (Haser, L. [1957]. Liege Inst. Astrophysics Reprint No. 394) model. We defined a restricted data set of comets that had at least three nights of observations. The restricted data set consists of 59 comets. We used ratios of production rates to study the trends in the data. We find two classes of comets: typical and carbon-chain depleted comets. Using a very strict definition of depleted comets, requiring C2and C3to both be depleted, we find 9% of our restricted data set comets to be depleted. Using a more relaxed definition that requires only C2to be below a threshold (similar to other researchers), we find 25% of the comets are depleted. Two-thirds of the depleted comets are Jupiter Family comets, while one-third are Long Period comets. 37% of the Jupiter Family comets are depleted, while 18.5% of the Long Period comets are depleted. We compare our results with other studies and find good agreement.