Nonthermal Mg I Emission at 12 Micron from Procyon

  title={Nonthermal Mg I Emission at 12 Micron from Procyon},
  author={N. Ryde and M. Richter},
  journal={The Astrophysical Journal},
We report on stellar Mg I emission at 12 μm from α CMi (Procyon), a star slightly hotter than the Sun. Solar Mg I emission is well known, and its formation was successfully explained in detail by Carlsson et al. Here, for the first time, we successfully model and compare synthetic spectra of the emission lines at 12 μm with observations of a star other than the Sun. The use of these lines as stellar diagnostics has been anticipated for 10 years or more (see, e.g., Carlsson et al.). We find that… Expand
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