Astronomical identification of CN^-, the smallest observed molecular anion

@inproceedings{Agndez2010AstronomicalIO,
  title={Astronomical identification of CN^-, the smallest observed molecular anion},
  author={M. Ag{\'u}ndez and J. Cernicharo and M. Gu{\'e}lin and C. Kahane and E. Roueff and J. Kłos and F. J. Aoiz and F. Lique and N. Marcelino and J. Goicoechea and M. Garcia and C. Gottlieb and M. McCarthy and P. Thaddeus},
  year={2010}
}
We present the first astronomical detection of a diatomic negative ion, the cyanide anion CN-, as well as quantum mechanical calculations of the excitation of this anion through collisions with para-H2. CN- is identified through the observation of the J = 2-1 and J = 3-2 rotational transitions in the C-star envelope IRC +10216 with the IRAM 30-m telescope. The U-shaped line profiles indicate that CN-, like the large anion C6H-, is formed in the outer regions of the envelope. Chemical and… Expand

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