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Using Neural Network models to estimate stellar ages from lithium equivalent widths: An EAGLES expansion (2024)
Journal Article
Weaver, G., Jeffries, R. D., & Jackson, R. J. (in press). Using Neural Network models to estimate stellar ages from lithium equivalent widths: An EAGLES expansion. Monthly Notices of the Royal Astronomical Society, https://doi.org/10.1093/mnras/stae2133

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 age from 7Li 6708Å equivalent width (LiEW) and effective temperatur... Read More about Using Neural Network models to estimate stellar ages from lithium equivalent widths: An EAGLES expansion.

The Gaia-ESO Survey: 3D dynamics of young groups and clusters from GES and Gaia EDR3 (2024)
Journal Article
Wright, N. J., Jeffries, R. D., Jackson, R. J., Sacco, G. G., Arnold, B., Franciosini, E., …Worley, C. C. (2024). The Gaia-ESO Survey: 3D dynamics of young groups and clusters from GES and Gaia EDR3. Monthly Notices of the Royal Astronomical Society, 533(1), 705–728. https://doi.org/10.1093/mnras/stae1806

We present the first large-scale 3D kinematic study of ∼2700 spectroscopically-confirmed young stars (< 20 Myr) in 18 star clusters and OB associations (hereafter groups) from the combination of Gaia astrometry and Gaia-ESO Survey spectroscopy... Read More about The Gaia-ESO Survey: 3D dynamics of young groups and clusters from GES and Gaia EDR3.

The Gaia-ESO Survey: The DR5 analysis of the medium-resolution GIRAFFE and high-resolution UVES spectra of FGK-type stars (2024)
Journal Article
Worley, C. C., Smiljanic, R., Magrini, L., Frasca, A., Franciosini, E., Montes, D., …Morbidelli, L. (2024). The Gaia-ESO Survey: The DR5 analysis of the medium-resolution GIRAFFE and high-resolution UVES spectra of FGK-type stars. Astronomy & Astrophysics, 684, Article A148. https://doi.org/10.1051/0004-6361/202347558

The Gaia-ESO Survey is an European Southern Observatory (ESO) public spectroscopic survey that targeted 105 stars in the Milky Way covering the major populations of the disk, bulge and halo. The observations were made using FLAMES on the VLT obtainin... Read More about The Gaia-ESO Survey: The DR5 analysis of the medium-resolution GIRAFFE and high-resolution UVES spectra of FGK-type stars.

A revised age greater than 50 Myr for the young cluster IC 4665 (2023)
Journal Article
Jeffries, R. D., Jackson, R. J., & Binks, A. S. (2023). A revised age greater than 50 Myr for the young cluster IC 4665. Monthly Notices of the Royal Astronomical Society, 526(1), 1260-1267. https://doi.org/10.1093/mnras/stad2845

IC 4665 is one of only a dozen young open clusters with a “lithium depletion boundary” (LDB) age. Using an astrometrically and spectroscopically filtered sample of cluster members, we show that both the positions of its low mass stars in Gaia absolut... Read More about A revised age greater than 50 Myr for the young cluster IC 4665.

The Gaia-ESO Survey: Homogenisation of stellar parameters and elemental abundances (2023)
Journal Article
Hourihane, A., François, P., Worley, C. C., Magrini, L., Gonneau, A., Casey, A. R., …Minkevičiūtė, R. (2023). The Gaia-ESO Survey: Homogenisation of stellar parameters and elemental abundances. Astronomy & Astrophysics, 676, Article A129. https://doi.org/10.1051/0004-6361/202345910

The Gaia-ESO Survey is a public spectroscopic survey that targeted greater than or similar to 10(5) stars covering all major components of the Milky Way from the end of 2011 to 2018, delivering its final public release in May 2022. Unlike other spect... Read More about The Gaia-ESO Survey: Homogenisation of stellar parameters and elemental abundances.

The Gaia-ESO Survey: empirical estimates of stellar ages from lithium equivalent widths (eagles) (2023)
Journal Article
Jeffries, R. D., Jackson, R. J., Wright, N. J., Weaver, G., Gilmore, G., Randich, S., …Zaggia, S. (2023). The Gaia-ESO Survey: empirical estimates of stellar ages from lithium equivalent widths (eagles). Monthly Notices of the Royal Astronomical Society, 523(1), 802-824. https://doi.org/10.1093/mnras/stad1293

We present an empirical model of age-dependent photospheric lithium depletion, calibrated using a large homogeneously analysed sample of 6200 stars in 52 open clusters, with ages from 2 to 6000 Myr and -0.3 < [Fe/H] < 0.2, observed in the Gaia-ESO sp... Read More about The Gaia-ESO Survey: empirical estimates of stellar ages from lithium equivalent widths (eagles).

Mapping the distribution of OB stars and associations in Auriga (2023)
Journal Article
Quintana, A. L., Wright, N. J., & Jeffries, R. D. (2023). Mapping the distribution of OB stars and associations in Auriga. Monthly Notices of the Royal Astronomical Society, 522(2), 3124-3137. https://doi.org/10.1093/mnras/stad1160

OB associations are important probes of recent star formation and Galactic structure. In this study, we focus on the Auriga constellation, an important region of star formation due to its numerous young stars, star-forming regions, and open clusters.... Read More about Mapping the distribution of OB stars and associations in Auriga.

The Gaia-ESO Survey: Preparing the ground for 4MOST and WEAVE galactic surveys (2023)
Journal Article
Nepal, S., Guiglion, G., de Jong, R., Valentini, M., Chiappini, C., Steinmetz, M., …Zaggia, S. (2023). The Gaia-ESO Survey: Preparing the ground for 4MOST and WEAVE galactic surveys. Astronomy & Astrophysics, 671, Article A61. https://doi.org/10.1051/0004-6361/202244765

Context. Originating from several sources (Big Bang, stars, cosmic rays) and being strongly depleted during stellar lifetime, the lithium element is of great interest as its chemical evolution in the Milky Way is not yet well understood. To help cons... Read More about The Gaia-ESO Survey: Preparing the ground for 4MOST and WEAVE galactic surveys.

The structure and 3D kinematics of vela OB2 (2022)
Journal Article
Armstrong, J. J., Wright, N. J., Jeffries, R. D., Jackson, R. J., & Cantat-Gaudin, T. (2022). The structure and 3D kinematics of vela OB2. Monthly Notices of the Royal Astronomical Society, 517(4), 5704 - 5720. https://doi.org/10.1093/mnras/stac3101

The kinematics of stars in OB associations can provide insights into their formation, dynamical evolution, and eventual fate. The low-mass stellar content of OB associations are sufficiently numerous as to provide a detailed sampling of their kinemat... Read More about The structure and 3D kinematics of vela OB2.

The Gaia-ESO Public Spectroscopic Survey: Motivation, implementation, GIRAFFE data processing, analysis, and final data products star (2022)
Journal Article
Gilmore, G., Randich, S., Worley, C., Hourihane, A., Gonneau, A., Sacco, G., …Zorec, J. (2022). The Gaia-ESO Public Spectroscopic Survey: Motivation, implementation, GIRAFFE data processing, analysis, and final data products star. Astronomy & Astrophysics, 66, Article A120. https://doi.org/10.1051/0004-6361/202243134

Context. The Gaia-ESO Public Spectroscopic Survey is an ambitious project designed to obtain astrophysical parameters and elemental abundances for 100 000 stars, including large representative samples of the stellar populations in the Galaxy, and a w... Read More about The Gaia-ESO Public Spectroscopic Survey: Motivation, implementation, GIRAFFE data processing, analysis, and final data products star.

The Gaia-ESO Public Spectroscopic Survey: Implementation, data products, open cluster survey, science, and legacy (2022)
Journal Article
Wright, Jeffries, Abbas, U., Borsen-Koch, V., Villanova, S., Wright, N., …Bragaglia, A. (2022). The Gaia-ESO Public Spectroscopic Survey: Implementation, data products, open cluster survey, science, and legacy. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202243141

Context. In the last 15 years different ground-based spectroscopic surveys have been started (and completed) with the general aim of delivering stellar parameters and elemental abundances for large samples of Galactic stars, complementing Gaia astrom... Read More about The Gaia-ESO Public Spectroscopic Survey: Implementation, data products, open cluster survey, science, and legacy.

Low mass young stars in the Milky Way unveiled by DBSCAN and Gaia EDR3. Mapping the star forming regions within 1.5 Kpc (2022)
Journal Article
Prisinzano, L., Damiani, F., Sciortino, S., Flaccomio, E., Guarcello, M., Micela, G., …Alcalá, J. (2022). Low mass young stars in the Milky Way unveiled by DBSCAN and Gaia EDR3. Mapping the star forming regions within 1.5 Kpc. Astronomy and Astrophysics, https://doi.org/10.1051/0004-6361/202243580

With an unprecedented astrometric and photometric data precision, Gaia EDR3 gives us, for the first time, the opportunity to systematically detect and map in the optical bands, the low mass populations of the star forming regions (SFRs) in the Milky... Read More about Low mass young stars in the Milky Way unveiled by DBSCAN and Gaia EDR3. Mapping the star forming regions within 1.5 Kpc.

The Gaia-ESO survey: Constraining evolutionary models and ages for young low mass stars with measurements of lithium depletion and rotation (2022)
Journal Article
Jeffries. (2022). The Gaia-ESO survey: Constraining evolutionary models and ages for young low mass stars with measurements of lithium depletion and rotation. Monthly Notices of the Royal Astronomical Society, 5727-5751. https://doi.org/10.1093/mnras/stac1245

A growing disquiet has emerged in recent years that standard stellar models are at odds with observations of the colour-magnitude diagrams (CMDs) and lithium depletion patterns of pre-main sequence stars in clusters. In this work we select 1246 high... Read More about The Gaia-ESO survey: Constraining evolutionary models and ages for young low mass stars with measurements of lithium depletion and rotation.

The Gaia-ESO Survey: Chemical tagging in the thin disk. Open clusters blindly recovered in the elemental abundance space (2022)
Journal Article
Spina, L., Magrini, L., Sacco, G. G., Casali, G., Vallenari, A., Tautvaisiene, G., …Zaggia, S. (2022). The Gaia-ESO Survey: Chemical tagging in the thin disk. Open clusters blindly recovered in the elemental abundance space. Astronomy & Astrophysics, 668, Article ARTN A16. https://doi.org/10.1051/0004-6361/202243316

Context. The chemical makeup of a star provides the fossil information of the environment where it formed. Under this premise, it should be possible to use chemical abundances to tag stars that formed within the same stellar association. This idea -... Read More about The Gaia-ESO Survey: Chemical tagging in the thin disk. Open clusters blindly recovered in the elemental abundance space.

The Gaia-ESO Survey: Membership probabilities for stars in 63 open and 7 globular clusters from 3D kinematics (2021)
Journal Article
Wright, & Jeffries. (2021). The Gaia-ESO Survey: Membership probabilities for stars in 63 open and 7 globular clusters from 3D kinematics. Monthly Notices of the Royal Astronomical Society, https://doi.org/10.1093/mnras/stab3032

Spectroscopy from the final internal data release of the Gaia-ESO Survey (GES) has been combined with Gaia EDR3 to assign membership probabilities to targets observed towards 63 Galactic open clusters and 7 globular clusters. The membership probabili... Read More about The Gaia-ESO Survey: Membership probabilities for stars in 63 open and 7 globular clusters from 3D kinematics.

The Gaia-ESO Survey: Galactic evolution of lithium from iDR6 (2021)
Journal Article
Romano, D., Magrini, L., Randich, S., Casali, G., Bonifacio, P., Jeffries, R. D., …Worley, C. (2021). The Gaia-ESO Survey: Galactic evolution of lithium from iDR6. Astronomy & Astrophysics, 653, Article A72. https://doi.org/10.1051/0004-6361/202141340

After more than 50 years, astronomical research still struggles to reconstruct the history of lithium enrichment in the Galaxy and to establish the relative importance of the various 7Li sources in enriching the interstellar medium (ISM) with this fr... Read More about The Gaia-ESO Survey: Galactic evolution of lithium from iDR6.

The Gaia-ESO survey: A lithium depletion boundary age for NGC 2232 (2021)
Journal Article
Binks, A. S., Jeffries, R. D., Jackson, R. J., Franciosini, E., Sacco, G. G., Bayo, A., …Zaggia, S. (2021). The Gaia-ESO survey: A lithium depletion boundary age for NGC 2232. Monthly Notices of the Royal Astronomical Society, 505(1), 1280-1292

Astrometry and photometry from {\it Gaia} and spectroscopic data from the {\it Gaia}-ESO Survey (GES) are used to identify the lithium depletion boundary (LDB) in the young cluster NGC 2232. A specialised spectral line analysis procedure was used to... Read More about The Gaia-ESO survey: A lithium depletion boundary age for NGC 2232.

The effects of rotation on the lithium depletion of G- and K-dwarfs in Messier 35 (2020)
Journal Article
Jeffries, R. D., Jackson, R. J., Sun, Q., & Deliyannis, C. P. (2021). The effects of rotation on the lithium depletion of G- and K-dwarfs in Messier 35. Monthly Notices of the Royal Astronomical Society, 500(1), 1158-1177. https://doi.org/10.1093/mnras/staa3141

New fibre spectroscopy and radial velocities from the WIYN telescope are used to measure photospheric lithium in 242 high-probability, zero-age-main-sequence (ZAMS) F- to K-type members of the rich cluster M35. Combining these with published rotation... Read More about The effects of rotation on the lithium depletion of G- and K-dwarfs in Messier 35.

The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity (2020)
Journal Article
Jeffries, R., & Wright, N. J. (2020). The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity. Astronomy and Astrophysics, https://doi.org/10.1051/0004-6361/202038688

Context. Reconstructing the Galactic evolution of lithium (Li) is the main tool used to constrain the source(s) of Li enrichment in the Galaxy. Recent results have suggested a decline in Li at supersolar metallicities, which may indicate reduced prod... Read More about The Gaia-ESO Survey: Galactic evolution of lithium at high metallicity.

The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc (2020)
Journal Article
Jeffries. (2020). The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc. Astronomy & Astrophysics, https://doi.org/10.1051/0004-6361/202038055

Context. In the era of large spectroscopic surveys, massive databases of high-quality spectra coupled with the products of the Gaia satellite provide tools to outline a new picture of our Galaxy. In this framework, an important piece of information i... Read More about The Gaia-ESO survey: the non-universality of the age-chemical-clocks-metallicity relations in the Galactic disc.