Detection of Interstellar HC4NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions

@article{Xue2020DetectionOI,
  title={Detection of Interstellar HC4NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions},
  author={Ci Xue and Eric R. Willis and Ryan A. Loomis and Kin Long Kelvin Lee and Andrew M. Burkhardt and Christopher N. Shingledecker and Steven B. Charnley and Martin A. Cordiner and Sergei Kalenskii and Michael C. McCarthy and Eric Herbst and Anthony J. Remijan and Brett A. McGuire},
  journal={The Astrophysical Journal Letters},
  year={2020},
  volume={900}
}
We report an astronomical detection of HC4NC for the first time in the interstellar medium with the Green Bank Telescope toward the TMC-1 molecular cloud with a minimum significance of 10.5σ. The total column density and excitation temperature of HC4NC are determined to be cm−2 and , respectively, using Markov chain Monte Carlo analysis. In addition to HC4NC, HCCNC is distinctly detected whereas no clear detection of HC6NC is made. We propose that the dissociative recombination of the… 

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