U.S.-Australia Cooperative Research on Carbon Isotopes in Comets

美国私家侦探彼得·韦辛格、苏珊·威科夫和他们的研究生马文·克莱恩将每三年访问澳大利亚国立大学的私家侦探布鲁斯·彼得森博士一次。本研究的目的是确定明亮彗星样品中的碳同位素丰度比，并通过观察分子和分子离子（CN、CH、c、c）的吸收谱线确定局部星际介质中的12C/13C丰度比。和CH+)在明亮的0型和b型恒星的视线范围内。此外，还建议开发CN的全荧光模型，以提高准确度，我们可以确定彗星的碳和氮同位素比率。研究人员将使用位于澳大利亚堪培拉附近的斯特罗莫洛山天文台的1.9米望远镜，该望远镜配有叠梯队光谱仪和照片计数阵列。在北半球，研究人员将使用基特峰国家天文台的码源望远镜和梯队光谱仪。这项研究本质上是1986年在美国-澳大利亚合作科学计划的支持下与哈雷彗星开始的成功合作努力的延续，它很重要，因为它可能揭示早期宇宙的形成。美国国内研究的额外财政支持来自美国国家航空航天局和美国国家科学基金会的资助。

One of the U.S. PIs, Peter A. Wehinger, Susan Wyckoff, and their graduate student, Marvin Kleine, will visit their Australian counterpart, Dr. Bruce A. Peterson of the Australian National University, once in each of three years. The goals of this research are to determine the carbon isotope abundance ratio in a sample of bright comets, and to determine the 12C/13C abundance ratio in the local interstellar medium by observing absorption lines of molecules and molecular ions (CN, CH, and CH+) in the lines-of-sight of bright 0- and B-type stars. Also proposed is the development of a full fluorescence model for CN to improve the accuracy with which we can determine the carbon and nitrogen isotope ratios in comets. The researchers will use the Mount Stromolo Observatory's 1.9 meter telescope located near Canberra, Australia, with its coude-echelle spectrograph and photo-counting array. In the Northern Hemisphere, the investigators will use the Kitt Peak National Observatory coude-feed telescope and echelle spectrograph. The research, which is essentially a continuation of a successful collaborative effort begun with Comet Halley in 1986 with U.S.-Australia Cooperative Science Program support, is important because of what it may reveal about the formation of the early universe. Additional financial support for the domestic U.S. research comes from NASA and NSF grants.