Molecular Carbon Chains and Rings in TMC-1

  title={Molecular Carbon Chains and Rings in TMC-1},
  author={David Foss{\'e} and Jos{\'e} Cernicharo and Maryvonne Gerin and Pierre Cox},
  journal={The Astrophysical Journal},
  pages={168 - 174}
We present mapping results in several rotational transitions of HC3N, C6H, both cyclic and linear C3H2 and C3H, toward the cyanopolyyne peak of the filamentary dense cloud TMC-1 using the IRAM 30 m and MPIfR 100 m telescopes. The spatial distribution of the cumulene carbon chain propadienylidene H2CCC (hereafter l-C3H2) is found to deviate significantly from the distributions of the cyclic isomer c-C3H2, HC3N, and C6H, which, in turn, look very similar. The cyclic over linear abundance ratio of… 

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