English

Gaia's view of the $\lambda$ Boo star puzzle

Solar and Stellar Astrophysics 2017-01-18 v1

Abstract

The evolutionary status of the chemically peculiar class of λ\lambda Boo stars has been intensely debated. It is now agreed that the λ\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 photometry. We find that no single formation mechanism is able to explain all the observations, and suggest that there are multiple channels producing λ\lambda Boo spectra. The relative importance of these channels varies with age, temperature and environment.

Keywords

Cite

@article{arxiv.1612.01528,
  title  = {Gaia's view of the $\lambda$ Boo star puzzle},
  author = {Simon J. Murphy and Ernst Paunzen},
  journal= {arXiv preprint arXiv:1612.01528},
  year   = {2017}
}

Comments

10 pages, 3 figures, fine for greyscale printing but colour is better