Gaia's view of the λ Boo star puzzle

  title={Gaia's view of the $\lambda$ Boo star puzzle},
  author={Simon J. Murphy and Ernst Paunzen},
  journal={Monthly Notices of the Royal Astronomical Society},
  • S. Murphy, E. Paunzen
  • Published 5 December 2016
  • Physics
  • Monthly Notices of the Royal Astronomical Society
The evolutionary status of the chemically peculiar class of $\lambda$ Boo stars has been intensely debated. It is now agreed that the $\lambda$ Boo phenomenon affects A stars of all ages, from star formation to the terminal age main sequence, but the cause of the chemical peculiarity is still a puzzle. We revisit the debate of their ages and temperatures in order to shed light on the phenomenon, using the new parallaxes in Gaia Data Release 1 with existing Hipparcos parallaxes and multicolour… 

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