Hifistars herschel/hifi observations of vy canis majoris : Molecular-line inventory of the envelope around the largest known star

@article{Alcolea2013HifistarsHO,
  title={Hifistars herschel/hifi observations of vy canis majoris : Molecular-line inventory of the envelope around the largest known star},
  author={Javier Alcolea and Valent{\'i}n Bujarrabal and Pere Planesas and David Teyssier and Jos{\'e} Cernicharo and Elvire De Beck and Leen Decin and Carsten Dominik and K. Justtanont and A. de Koter and A. P. Marston and Gary J. Melnick and Karl M. Menten and David A. Neufeld and H. Olofsson and M. R. Schmidt and Fredrik Schoier and Ryszard Szczerba and L. B. F. M. Waters},
  journal={Astronomy and Astrophysics},
  year={2013},
  volume={559},
  pages={1-25}
}
Aims. The study of the molecular gas in the circumstellar envelopes of evolved stars is normally undertaken by observing lines of CO (and other species) in the millimetre-wave domain. In general, the excitation requirements of the observed lines are low at these wavelengths, and therefore these observations predominantly probe the cold outer envelope while studying the warm inner regions of the envelopes normally requires sub-millimetre (sub-mm) and far-infrared (FIR) observational data… 

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