New molecules in IRC +10216: confirmation of C5S and tentative identification of MgCCH, NCCP, and SiH3CN

  title={New molecules in IRC +10216: confirmation of C5S and tentative identification of MgCCH, NCCP, and SiH3CN},
  author={Marcelino Ag'undez and Jos{\'e} Cernicharo and Michel Gu'elin},
  journal={Astronomy and Astrophysics},
The carbon-star envelope IRC +10216 harbors a rich variety of molecules, with more than 80 detected to date. During the course of a λ 3m m survey of IRC+10216 carried out with the IRAM 30-m telescope we have detected various weak lines, with antenna temperatures of a few mK, which we assign to rotational transitions of four new molecules. The observation of three lines of C5S confirms a previous tentative identification of this molecule based on a line at 24.0 GHz. We also report the tentative… 

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