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20112026
most citedInvestigating the Upper Scorpius OB association with HERMES. I. The spectroscopic sample and 6D kinematics

9 citations · 24 across the 7 of their papers we have counts for

collaborators

8 papers

astro-ph.SR2026

Open Clusters as Laboratories for Cool Star Evolution: Highlights from the Cool Stars 23 Splinter Session

Deepak Chahal, Beatrice Caccherano, Edward Gillen +16

Open clusters remain among the most powerful laboratories for calibrating how fundamental stellar properties such as rotation, magnetic activity, surface chemistry, and internal st…

astro-ph.SR2026

Lithium-rich M-dwarfs at the ZAMS: Evidence for planetary engulfment?

R. D. Jeffries, R. J. Jackson, I. Baraffe

We identify 6 early M-dwarfs, in 3 open clusters (NGC 2451a, Blanco 1 and NGC 2516) at ages of 50-200 Myr, that are anomalously enriched in lithium compared with Li-depleted siblin…

astro-ph.GA2026

3D Rotation of the Open Cluster NGC 2516

Nicholas J. Wright, R. D. Jeffries, M. A. Whalley

We have combined Gaia astrometry with Gaia-ESO Survey radial velocities to measure the 3D rotation of the open cluster NGC 2516. We compiled a sample of 376 members with astrometry…

astro-ph.SR2025★ 9 cited

Investigating the Upper Scorpius OB association with HERMES. I. The spectroscopic sample and 6D kinematics

Joseph J. Armstrong, Jonathan C. Tan, Nicholas J. Wright +5

We present results from a large spectroscopic survey of the nearest young association to the Sun, Upper Scorpius, conducted using 2dF/HERMES on the Anglo-Australian Telescope. We u…

astro-ph.SR2025

The growth of a lithium abundance dispersion in pre main sequence stars

R. J. Jackson, R. D. Jeffries, E. Tognelli

Lithium is predicted, and observed, to be depleted in contracting, low-mass pre main sequence (PMS) stars. Yet these stars reach the zero age main sequence (ZAMS) with a spread in…

astro-ph.SR2024

Using Neural Network Models to Estimate Stellar Ages from Lithium Equivalent Widths: An EAGLES Expansion

George Weaver, Robin D. Jeffries, Richard J. Jackson

We present an Artificial Neural Network (ANN) model of photospheric lithium depletion in cool stars (3000 < Teff / K < 6500), producing estimates and probability distributions of a…

astro-ph.GA2014★ 7 cited

An Anomalous Extinction Law in the Cep OB3b Young Cluster: Evidence for dust processing during gas dispersal

Thomas S. Allen, Jakub J. Prchlik, S. Thomas Megeath +4

We determine the extinction law through Cep OB3b, a young cluster of 3000 stars undergoing gas dispersal. The extinction is measured toward 76 background K giants identified with M…

astro-ph.SR2011★ 8 cited

Are There Age Spreads in Star Forming Regions?

R. D. Jeffries

A luminosity spread at a given effective temperature is ubiquitously seen in the Hertzsprung-Russell (HR) diagrams of young star forming regions and often interpreted in terms of a…