Far-infrared Detection of C3 in Sagittarius B2 and IRC +10216

  title={Far-infrared Detection of C3 in Sagittarius B2 and IRC +10216},
  author={Jos{\'e} Cernicharo and Javier R. Goicoechea and Emmanuel Caux},
  journal={The Astrophysical Journal Letters},
  pages={L199 - L202}
We report on the detection of nine lines of the ν2 bending mode of triatomic carbon, C3, in the direction of Sagittarius B2. The R(4) and R(2) lines of C3 have been also detected in the carbon-rich star IRC +10216. The abundances of C3 in the direction of Sgr B2 and IRC +10216 are ≃3 × 10-8 and ≃10-6, respectively. In Sgr B2 we have also detected the 23-12 line of NH with an abundance of a few times 10-9. Polyatomic molecules will have a weak contribution from their pure rotational spectrum to… 

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