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Related papers: Lithium in the Intermediate-Age Open Cluster, NGC …

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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--6000 Myr and $-0.3<{\rm [Fe/H}]<0.2$, observed in…

The study of star clusters has advanced our understanding of stellar evolution, Galactic chemical evolution and nucleosynthesis. Here we investigate the composition of turn-off stars in the intriguing open cluster, NGC 6791, which is old,…

Solar and Stellar Astrophysics · Physics 2015-06-23 Ann Merchant Boesgaard , Michael G. Lum , Constantine P. Deliyannis

Archival WFC3/UVIS imaging of Arp 299 (NGC 3690E + NGC 3690W) is retrieved to investigate the young massive cluster (YMC) population of this ongoing merger. We extract 2182 cluster candidates, including 1323 high confidence photometric…

Astrophysics of Galaxies · Physics 2018-10-24 Zara Randriamanakoto , Petri Väisänen , Stuart D. Ryder , Princy Ranaivomanana

In this work we present the results of our analysis of medium-resolution LAMOST spectra of candidate members of the cluster NGC 1647 with the aim of determining the stellar parameters, activity level, lithium abundance, and to study the…

Solar and Stellar Astrophysics · Physics 2026-04-14 A. Frasca , M. Qin , J. ALonso-Santiago , G. Catanzaro , J. N. Fu , J. Y. Zhang , A. Bragaglia

We have identified twenty-seven candidate very low mass members of the relatively young Alpha Persei open cluster from a six square degree CCD imaging survey. Based on their I magnitudes and the nominal age and distance to the cluster,…

A five-dimensional interpolation method and corresponding computer program are developed for using published calculations to determine the non-LTE correction {\Delta\}NLTE to the lithium abundance log{\epsilon}(Li) derived from the Li I…

Solar and Stellar Astrophysics · Physics 2017-10-18 L. S. Lyubimkov , D. V. Petrov

This work presents a homogeneous determination of lithium abundances in a large sample of giant-planet hosting stars (N=117), and a control sample of disk stars without detected planets (N=145). The lithium abundances were derived using a…

Solar and Stellar Astrophysics · Physics 2010-11-04 L. Ghezzi , K. Cunha , V. V. Smith , R. de la Reza

We obtain lithium abundances for G and K stars in Blanco 1, an open cluster with an age similar to, or slightly younger than, the Pleiades. We critically examine previous spectroscopic abundance analyses of Blanco 1 and conclude that while…

Astrophysics · Physics 2009-10-30 R. D. Jeffries , D. J. James

Aims. This study aims to determine the level and constancy of the Spite plateau as definitively as possible from homogeneous high-quality VLT-UVES spectra of 19 of the most metal-poor dwarf stars known. Methods. Our high-resolution (R ~…

We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Melendez , L. Casagrande , I. Ramirez , M. Asplund , W. J. Schuster

Evolutionary trends in the surface abundances of heavier elements have recently been identified in the globular cluster NGC 6397 ([Fe/H]=-2), indicating the operation of atomic diffusion in these stars. Such trends constitute important…

Astrophysics · Physics 2009-11-13 K. Lind , A. J. Korn , P. S. Barklem , F. Grundahl

We identified star clusters in archived HST/WFPC2 images of the merger and ultra-luminous infrared galaxy NGC 6240, with the aim of investigating whether star cluster properties (luminosity, age and mass) in such an extreme environment…

Astrophysics · Physics 2009-11-10 A. Pasquali , R. de Grijs , J. S. Gallagher

We report novel observational evidence on the evolutionary status of lithium-rich giant stars by combining asteroseismic and lithium abundance data. Comparing observations and models of the asteroseismic gravity-mode period spacing…

Solar and Stellar Astrophysics · Physics 2021-05-26 Raghubar Singh , Bacham E. Reddy , Simon W. Campbell , Yerra Bharat Kumar , Mathieu Vrard

WIYN/HYDRA spectra in the Li 6708 Angstrom region have been obtained for 332 probable members of the old open cluster, NGC 6819. Preliminary analysis shows a pattern of Li depletion from the top of the turnoff to the base of the giant…

Solar and Stellar Astrophysics · Physics 2015-06-15 Barbara J. Anthony-Twarog , Constantine P. Deliyannis , Evan Rich , Bruce A. Twarog

Using the sample of 348 stars from the PennState-Torun Centre for Astronomy Planet Search, for which uniformly determined atmospheric parameters are available, with chemical abundances and rotational velocities presented here, we…

Solar and Stellar Astrophysics · Physics 2015-06-22 M. Adamow , A. Niedzielski , E. Villaver , A. Wolszczan , G. Nowak

We present the first systematic study of lithium abundance in a chemically homogeneous sample of 27 red supergiants (RSGs) in the young Perseus complex. For these stars, accurate stellar parameters and detailed chemical abundances of iron…

Solar and Stellar Astrophysics · Physics 2022-06-06 C. Fanelli , L. Origlia , A. Mucciarelli , N. Sanna , E. Oliva , E. Dalessandro

We report a detailed spectroscopic abundance analysis for a sample of 18 F-K dwarfs of the young open cluster IC 4665. Stellar parameters and element abundances of Li, O, Mg, Si, Ca, Ti, Cr, Fe and Ni have been derived using the…

Astrophysics · Physics 2009-11-13 Z. -X. Shen , B. Jones , D. N. C. Lin , X. -W. Liu , S. -L. Li

In the globular cluster NGC2808, a quasi-standard initial lithium abundance is derived for a red giant belonging to the `extreme' population, characterized by a large helium overabundance, and by abundances of proton capture elements…

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 (PMS) stars in clusters. In this work we…

We investigate here the lithium content of young low-mass stars in the 5~Myr-old star forming region NGC~2264 and its relationship with rotation. We combine lithium equivalent width measurements, EW(Li), from the Gaia-ESO Survey with the…