Photon-dominated Chemistry in the Nucleus of M82: Widespread HOC+ Emission in the Inner 650 Parsec Disk

@article{Fuente2005PhotondominatedCI,
  title={Photon-dominated Chemistry in the Nucleus of M82: Widespread HOC+ Emission in the Inner 650 Parsec Disk},
  author={Asunci{\'o}n Fuente and Santiago Garc{\'i}a-Burillo and Maryvonne Gerin and David Teyssier and Antonio Usero and J. R. Rizzo and Pablo de Vicente},
  journal={The Astrophysical Journal Letters},
  year={2005},
  volume={619},
  pages={L155 - L158}
}
The nucleus of M82 has been mapped in several 3 and 1 mm lines of CN, HCN, C2H, c-C3H2, CH3C2H, HC3N, and HOC+ using the IRAM 30 m telescope. These species have been purposely selected as good tracers of photon-dominated chemistry. We have measured [CN]/[HCN] ~ 5 in the inner 650 pc galaxy disk. Furthermore, we have detected the HOC+ 1 → 0 line with an intensity similar to that of the H13CO+ 1 → 0 line. This implies an [HCO+]/[HOC+] ratio of ~40. These results corroborate the existence of a… 

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