Texes Observations of M Supergiants: Dynamics and Thermodynamics of Wind Acceleration

@article{Harper2009TexesOO,
  title={Texes Observations of M Supergiants: Dynamics and Thermodynamics of Wind Acceleration},
  author={G. Harper and M. Richter and N. Ryde and A. Brown and J. Brown and T. Greathouse and S. Strong},
  journal={The Astrophysical Journal},
  year={2009},
  volume={701},
  pages={1464-1483}
}
We have detected [Fe II] 17.94 μm and 24.52 μm emission from a sample of M supergiants (μ Cep, α Sco, α Ori, CE Tau, AD Per, and α Her) using the Texas Echelon Cross Echelle Spectrograph on NASA's Infrared Telescope Facility. These low opacity emission lines are resolved at R 50, 000 and provide new diagnostics of the dynamics and thermodynamics of the stellar wind acceleration zone. The [Fe II] lines, from the first excited term (a 4 F), are sensitive to the warm plasma where energy is… Expand
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