Gaia's view of the λ Boo star puzzle

Author(s)
Simon J. Murphy, Ernst Paunzen
Abstract

The evolutionary status of the chemically peculiar class of λ Boo stars has been intensely debated. It is now agreed that the λ 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 Boo spectra. The relative importance of these channels varies with age, temperature and environment.

Organisation(s)
Department of Astrophysics
External organisation(s)
Western Sydney University, Masaryk University
Journal
Monthly Notices of the Royal Astronomical Society
Volume
466
Pages
546 - 555
No. of pages
10
ISSN
0035-8711
DOI
https://doi.org/10.1093/mnras/stw3141
Publication date
04-2017
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/c30a3770-cc4f-4059-b3a2-43a458278c5b