The Isotopic Abundances of Magnesium in Stars

  title={The Isotopic Abundances of Magnesium in Stars},
  author={P. L. Gay and David L. Lambert},
  journal={The Astrophysical Journal},
  pages={260 - 270}
Isotopic abundance ratios 24Mg : 25Mg : 26Mg are derived for 20 stars from high-resolution spectra of the MgH A-X 0-0 band at 5140 Å. With the exception of the weak G-band giant HR 1299, the stars are dwarfs that sample the metallicity range -1.8 < [Fe/H] < 0.0. The abundance of 25Mg and 26Mg relative to the dominant isotope 24Mg decreases with decreasing [Fe/H] in fair accord with predictions from a recent model of Galactic chemical evolution in which the Mg isotopes are synthesized by massive… 

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