A lithium depletion boundary age of 21 Myr for the Beta Pictoris moving group

Binks, A. S.; Jeffries, R. D.

Abstract

Optical spectroscopy is used to confirm membership for eight low-mass candidates in the young Beta Pic moving group (BPMG) via their radial velocities, chromospheric activity and kinematic parallaxes. We searched for the presence of the Li I 6708 Å resonance feature and combined the results with literature measurements of other BPMG members to find the age-dependent lithium depletion boundary (LDB) – the luminosity at which Li remains unburned in a coeval group. The LDB age of the BPMG is 21 ± 4 Myr and insensitive to the choice of low-mass evolutionary models. This age is more precise, likely to be more accurate, and much older than that commonly assumed for the BPMG. As a result, substellar and planetary companions of BPMG members will be more massive than previously thought.

Citation

Binks, A. S., & Jeffries, R. D. (2014). A lithium depletion boundary age of 21 Myr for the Beta Pictoris moving group. Monthly Notices of the Royal Astronomical Society: Letters, 438(1), L11-L15. https://doi.org/10.1093/mnrasl/slt141

• Journal Article Type: Article
• Acceptance Date: Oct 9, 2013
• Online Publication Date: Nov 19, 2013
• Publication Date: Feb 11, 2014
• Deposit Date: Jun 13, 2023
• Journal: Monthly Notices of the Royal Astronomical Society: Letters
• Electronic ISSN: 1745-3933
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 438
• Issue: 1
• Pages: L11-L15
• DOI: https://doi.org/10.1093/mnrasl/slt141
• Keywords: Space and Planetary Science; Astronomy and Astrophysics