The lithium depletion boundary in NGC 2547 as a test of pre-main-sequence evolutionary models

Jeffries, Robin D.; Oliveira, Joanna M.

Abstract

Intermediate resolution spectroscopy from the ESO Very Large Telescope is analysed for 63 photometrically selected low-mass (0.08-0.30 Msun) candidates of the open cluster NGC 2547. We have confirmed membership for most of these stars using radial velocities, and found that lithium remains undepleted for cluster stars with I>17.54+/-0.14 and K_{s}>14.86+/-0.12. From these results, several pre-main-sequence evolutionary models give almost model independent ages of 34-36 Myr, with a precision of 10 per cent. These ages are only slightly larger than the ages of 25-35 (+/-5) Myr obtained using the same models to fit isochrones to higher mass stars descending towards the zero age main sequence (ZAMS), both in empirically calibrated and theoretical colour-magnitude diagrams. This agreement between age determinations in different mass ranges is an excellent test of the current generation of low-mass pre-main sequence stellar models and lends confidence to ages determined with either method between 30 and 120 Myr.

Citation

Jeffries, R. D., & Oliveira, J. M. (2005). The lithium depletion boundary in NGC 2547 as a test of pre-main-sequence evolutionary models. Monthly Notices of the Royal Astronomical Society, 358(1), 13 -29. https://doi.org/10.1111/j.1365-2966.2005.08820.x

• Journal Article Type: Article
• Acceptance Date: Nov 3, 2004
• Online Publication Date: Mar 21, 2005
• Publication Date: 2005-03
• Publicly Available Date: May 26, 2023
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 358
• Issue: 1
• Pages: 13 -29
• DOI: https://doi.org/10.1111/j.1365-2966.2005.08820.x
• Keywords: stars, abundancies, late-type stars
• Publisher URL: http://dx.doi.org/10.1111/j.1365-2966.2005.08820.x