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Detection of HC11N in the Cold Dust Cloud TMC-1

M. B. Bell·P. A. Feldman·M. J. Travers·M. C. McCarthy·C. A. Gottlieb·P. Thaddeus
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Abstract

Two consecutive rotational transitions of the long cyanopolyyne HC11N, J=39-38, and J=38-37, have been detected in the cold dust cloud TMC-1 at the frequencies expected from recent laboratory measurements by Travers et al. (1996), and at about the expected intensities. The astronomical lines have a mean radial velocity of 5.8(1) km/s, in good agreement with the shorter cyanopolyynes HC7N and HC9N observed in this very sharp-lined source [5.82(5) and 5.83(5) km/s, respectively]. The column density of HC11N is calculated to be 2.8x10^(11) cm^(-2). The abundance of the cyanopolyynes decreases smoothly with length to HC11N, the decrement from one to the next being about 6 for the longer carbon chains.

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M. B. Bell, P. A. Feldman, M. J. Travers, M. C. McCarthy, C. A. Gottlieb, P. Thaddeus. 1997-04-23. Detection of HC11N in the Cold Dust Cloud TMC-1. https://doi.org/10.1086/310732

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