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arXiv · 1610.00524

A New Reference Chemical Composition for TMC-1

P. Gratier·L. Majumdar·M. Ohishi·E. Roueff·J. -C. Loison·K. M. Hickson·V. Wakelam
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Abstract

Recent detections of complex organic molecules in dark clouds have rekindled interest in the astrochemical modeling of these environments. Because of its relative closeness and rich molecular complexity, TMC-1 has been extensively observed to study the chemical processes taking place in dark clouds. We use local thermodynamical equilibrium radiative transfer modeling coupled with a Bayesian statistical method which takes into account outliers to analyze the data from the Nobeyama spectral survey of TMC-1 between 8 and 50 GHz. We compute the abundance relative to molecular hydrogen of 57 molecules, including 19 isotopologues in TMC-1 along with their associated uncertainty. The new results are in general agreement with previous abundance determination from Ohishi & Kaifu and the values reported in the review from Agundez & Wakelam. However, in some cases, large opacity and low signal to noise effects allow only upper or lower limits to be derived, respectively.

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P. Gratier, L. Majumdar, M. Ohishi, E. Roueff, J. -C. Loison, K. M. Hickson, V. Wakelam. 2016-10-03. A New Reference Chemical Composition for TMC-1. https://doi.org/10.3847/0067-0049%2F225%2F2%2F25

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