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arXiv · 1910.03688

Investigating the Temperature Distribution of Diatomic Carbon in Comets using the Swan Bands

Tyler Nelson·Anita Cochran
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Abstract

We present high spectral-resolution observations of comets 122P/de Vico and 153P/Ikeya-Zhang obtained with the Tull Coud\'{e} spectrograph on the 2.7m Harlan J. Smith telescope of McDonald Observatory. We used these data to study the distribution of the lines of the $\mathrm{d} ^3\Pi_g - \mathrm{a} ^3\Pi_u$ C$_2$ (Swan) bands. We show that the data are best represented with two rotational temperatures, with the lowest energy lines being at a relatively cool temperature and the higher energy lines being at a higher temperature. We discuss the implications of this two temperature distribution and suggest future work.

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Tyler Nelson, Anita Cochran. 2019-10-08. Investigating the Temperature Distribution of Diatomic Carbon in Comets using the Swan Bands. https://doi.org/10.3847/1538-3881%2Fab4c93

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