The IRAM-30 m line survey of the Horsehead PDR - II. First detection of the l-C3H+ hydrocarbon cation

  title={The IRAM-30 m line survey of the Horsehead PDR - II. First detection of the l-C3H+ hydrocarbon cation},
  author={J{\'e}r{\^o}me Pety and Pierre Gratier and Viviana V. Guzm'an and {\`E}velyne Roueff and Maryvonne Gerin and Javier R. Goicoechea and S{\'e}bastien Bardeau and Albrecht Sievers and Franck Le Petit and Jacques Le Bourlot and Arnaud Belloche and Dahbia Talbi},
  journal={Astronomy and Astrophysics},
Context. Pure gas-phase chemistry models do not succeed in reproducing the measured abundances of small hydrocarbons in the interstellar medium. Information on key gas-phase progenitors of these molecules sheds light on this problem. Aims: We aim to constrain the chemical content of the Horsehead mane with a millimeter unbiased line survey at two positions, namely the photo-dissociation region (PDR) and the nearby shielded core. This project revealed a consistent set of eight unidentified lines… 

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