• Corpus ID: 227208779

The GALAH Survey: Chemical Clocks.

  title={The GALAH Survey: Chemical Clocks.},
  author={Michael R. Hayden and Sanjib Sharma and Joss Bland-Hawthorn and Lorenzo Spina and Sven Buder and Martin Asplund and Andrew R. Casey and Gayandhi M. De Silva and Valentina D’Orazi and Kenneth C. Freeman and Janez Kos and Geraint F. Lewis and Jane Lin and Karin Lind and Sarah L. Martell and Katharine J. Schlesinger and Jeffrey D. Simpson and Daniel B. Zucker and Toma{\vz} Zwitter and Boquan Chen and Klemen {\vC}otar and Diane K. Feuillet and Jonti Horner and Meridith Joyce and Thomas Nordlander and Dennis Stello and Thor Tepper-Garc{\'i}a and Yuan-Sen Ting and Purmortal Wang and Robert A. Wittenmyer},
  journal={arXiv: Astrophysics of Galaxies},
Previous studies have found that the elemental abundances of a star correlate directly with its age and metallicity. Using this knowledge, we derive ages for a sample of 250,000 stars taken from GALAH DR3 using only their overall metallicity and chemical abundances. Stellar ages are estimated via the machine learning algorithm $XGBoost$, using main sequence turnoff stars with precise ages as our input training set. We find that the stellar ages for the bulk of the GALAH DR3 sample are accurate… 
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