The M Dwarf GJ 436 and its Neptune-Mass Planet

  title={The M Dwarf GJ 436 and its Neptune-Mass Planet},
  author={Holly L. Maness and Geoffrey W. Marcy and Eric B. Ford and Peter Hauschildt and Alexander T. Shreve and Gibor B. Basri and R. Paul Butler and Steven S. Vogt},
  journal={Publications of the Astronomical Society of the Pacific},
  • H. Maness, G. Marcy, S. Vogt
  • Published 11 August 2006
  • Physics, Geology
  • Publications of the Astronomical Society of the Pacific
We determine stellar parameters for the M dwarf GJ 436, which hosts a Neptune-mass planet. We employ primarily spectral modeling at low and high resolution, examining the agreement between model and observed optical spectra of five comparison stars of type M0-M3. The modeling of high-resolution optical spectra suffers from uncertainties in TiO transitions, affecting the predicted strengths of both atomic and molecular lines in M dwarfs. The determination of Teff, gravity, and metallicity from… 

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