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Related papers: Chemical (in)homogeneity and atomic diffusion in t…

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We present new FLAMES@VLT spectroscopic observations of 30 stars in the field of the LMC stellar cluster NGC 1866. NGC 1866 is one of the few young and massive globular cluster that is close enough so that its stars can be individually…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. Mucciarelli , S. Cristallo , E. Brocato , L. Pasquini , O. Straniero , E. Caffau , G. Raimondo , A. Kaufer , I. Musella , V. Ripepi , M. Romaniello , A. R. Walker

Past studies have already shown that stars in open clusters are chemically homogeneous (e.g. De Silva et al. 2006, 2007 and 2009). These results support the idea that stars born from the same giant molecular cloud should have the same…

Solar and Stellar Astrophysics · Physics 2015-07-28 S. Blanco-Cuaresma , C. Soubiran , U. Heiter

A homogeneous spectroscopic analysis of unevolved and evolved stars in the metal-poor globular cluster NGC 6397 with FLAMES-UVES reveals systematic trends of stellar surface abundances that are likely caused by atomic diffusion. This…

Stellar surface abundances are records of the state of the gas from which stars formed, and thus trace how individual elements have mixed into the surrounding medium following their ejection from stars. In this work, we test the common…

We explore the possible connection between the open cluster IC 2391 and the unbound Argus association identified by the SACY survey. In addition to common kinematics and ages between these two systems, here we explore their chemical…

Solar and Stellar Astrophysics · Physics 2015-06-12 G. M. De Silva , V. D'Orazi , C. Melo , C. A. O. Torres , M. Gieles , G. R. Quast , M. Sterzik

White dwarfs are excellent forensic tools for studying end-of-life issues surrounding low- and intermediate-mass stars, and the old, solar-metallicity open star cluster Messier 67 is a proven laboratory for the study of stellar evolution…

Solar and Stellar Astrophysics · Physics 2018-11-02 Kurtis A. Williams , Paul A. Canton , A. Bellini , Michael Bolte , Kate H. R. Rubin , Alexandros Gianninas , Mukremin Kilic

Open clusters have been extensively used as tracers of Galactic chemical evolution, as their constituent stars possess shared characteristics, including age, Galactocentric radius, metallicity, and chemical composition. By examining the…

Observations of elemental abundances in the Galaxy have repeatedly shown an intrinsic scatter as a function of time and metallicity. The standard approach to chemical evolution does not attempt to address this scatter in abundances since…

Astrophysics · Physics 2009-10-28 Craig J. Copi

Context. The modelling of chemical transport mechanisms is crucial for accurate stellar characterizations. Atomic diffusion is one of these processes and it is commonly included in stellar models. However, it is usually neglected for F-type…

Solar and Stellar Astrophysics · Physics 2024-01-29 Nuno Moedas , Diego Bossini , Morgan Deal , Margarida Cunha

We present a line-by-line differential analysis of a sample of 16 planet hosting stars and 68 comparison stars using high resolution, high signal-to-noise ratio spectra gathered using Keck. We obtained accurate stellar parameters and…

Solar and Stellar Astrophysics · Physics 2020-05-22 F. Liu , D. Yong , M. Asplund , H. S. Wang , L. Spina , L. Acuna , J. Melendez , I. Ramirez

The recently discovered coeval, moving groups of young stellar objects in the solar neighborhood represent invaluable laboratories to study recent star formation and to search for high metallicity stars which can be included in future…

Solar and Stellar Astrophysics · Physics 2016-11-25 P. Viana Almeida , N. C. Santos , C. Melo , M. Ammler-von Eiff , C. A. O. Torres , G. R. Quast , J. F. Gameiro , M. Sterzik

Recent work has used spectra of about 5000 stars in NGC 6397 that were extracted from a MUSE mosaic to determine the atmospheric parameters for these stars by fitting the spectra against the Goettingen Spectral Library. A significant change…

Solar and Stellar Astrophysics · Physics 2020-04-08 Rashi Jain , Philippe Prugniel , Lucimara Martins , Ariane Lançon

We present new evolutionary stellar models suitable for old Population I clusters, discussing both the consequences of the most recent improvements in the input physics and the effect of element diffusion within the stellar structures.…

Astrophysics · Physics 2009-10-31 V. Castellani , S. Degl'Innocenti , M. Marconi

We derive atmospheric parameters and chemical abundances in young G-, K-, and M-type stars (temperatures between 6500 and 3100 K) using infrared APOGEE-2 spectra. Atmospheric parameters were determined for 548 young stars in the Orion…

It is generally accepted today that Galactic globular clusters (GGCs) consist of at least two generations of stars that are different in their chemical composition and perhaps age. However, knowledge about the kinematical properties of…

Solar and Stellar Astrophysics · Physics 2014-09-05 A. Kucinskas , V. Dobrovolskas , P. Bonifacio

Context. Open clusters provide valuable information on stellar nucleosynthesis and the chemical evolution of the Galactic disc, as their age and distances can be measured more precisely with photometry than for field stars. Aims. Our aim is…

Recent work has shown that most globular clusters have at least two chemically distinct components, as well as cluster-to-cluster differences in the mean [O/Fe], [Mg/Fe], and [Si/Fe] ratios at similar [Fe/H] values. In order to investigate…

Solar and Stellar Astrophysics · Physics 2015-06-05 Don A. VandenBerg , Peter A. Bergbusch , Aaron Dotter , Jason W. Ferguson , Georges Michaud , Jacques Richer , Charles Proffitt

We investigate the origin of the abundance variations observed among similarly aged F and G dwarfs in the local Galactic disk. We present arguments in support of combined infall of metal-deficient gas and sequential enrichment by successive…

Astrophysics · Physics 2008-02-03 Bob van den Hoek , Teije de Jong

Precise stellar ages from asteroseismology have become available and can help setting stronger constraints on the evolution of the Galactic disc components. Recently, asteroseismology has confirmed a clear age difference in the solar…

Astrophysics of Galaxies · Physics 2019-03-06 E. Spitoni , V. Silva Aguirre , F. Matteucci , F. Calura , V. Grisoni

HARPS spectra with signal-to-noise ratios S/N > 600 at 6000 A were analysed with MARCS model atmospheres to obtain 1D LTE abundances of C, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Sr, and Y for 72 nearby solar-type stars with metallicities in…

Solar and Stellar Astrophysics · Physics 2020-08-19 P. E. Nissen , J. Christensen-Dalsgaard , J. R. Mosumgaard , V. Silva Aguirre , E. Spitoni , K. Verma.