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Related papers: Explaining the decrease in ISM lithium at super-so…

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We present a comprehensive study of the abundance evolution of the elements from H to U in the Milky Way halo and local disk. We use a consistent chemical evolution model, metallicity dependent isotopic yields from low and intermediate mass…

Astrophysics of Galaxies · Physics 2018-02-21 N. Prantzos , C. Abia , M. Limongi , A. Chieffi , S. Cristallo

We report medium-resolution (1-2 A) spectroscopy and broadband (UBV) photometry for a sample of 39 bright stars (the majority of which are likely to be giants) selected as metal-deficient candidates from an objective-prism survey…

We develop an approach for fitting the results of modeling of wriggling radial large scale iron pattern along the Galactic disk, derived over young (high massive) Cepheids, with the metallicity distribution, obtained using low mass long…

Astrophysics of Galaxies · Physics 2020-01-08 Yu. N. Mishurov , R. V. Tkachenko

Star formation drives changes in the compositions of galaxies, fusing H and He into heavier nuclei. This paper investigates the differences in abundance evolution between metal and non-metal isotopes using recent models of Galactic chemical…

Astrophysics of Galaxies · Physics 2025-10-13 James W. Johnson , Miqaela K. Weller , Ryan J. Cooke

We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We find…

Astrophysics · Physics 2008-11-26 M. H. Pinsonneault , G. Steigman , T. P. Walker , V. K. Narayanan

We combine the estimated metallicities [Fe/H], abundances [\alpha/Fe], positions and motions of a sample of 27,500 local (7<R/kpc<9, 0.5<|z|/kpc<2.5) SDSS/SEGUE G-type dwarf stars to investigate the chemo-orbital properties of the Milky…

Astrophysics of Galaxies · Physics 2015-06-03 Chao Liu , Glenn van de Ven

Recent new high-precision abundance data for Galactic halo stars suggest important primary nitrogen production in very metal-poor massive stars. Here, we compute a new model for the chemical evolution of the Milky Way aimed at explaining…

Astrophysics · Physics 2009-11-10 C. Chiappini , F. Matteucci , S. K. Ballero

By means of N-body simulations, we show that radial migration in galaxy disks, induced by bar and spiral arms, leads to significant azimuthal variations in the metallicity distribution of old stars at a given distance from the galaxy…

Astrophysics of Galaxies · Physics 2015-06-12 P. Di Matteo , M. Haywood , F. Combes , B. Semelin , O. N. Snaith

I review basic observational features in Population I stars which strongly implicate rotation as a mixing agent; these include dispersion at fixed temperature in coeval populations and main sequence lithium depletion for a range of masses…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. H. Pinsonneault

The discrepancy between the predictions of primordial nucleosynthesis and the observed lithium abundance in Spite plateau stars has been attributed either to a challenge to the standard model of nucleosynthesis or to stellar processes…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-17 Oswaldo D. Miranda

We present the mass-metallicity (MZ) and luminosity-metallicity (LZ) relations at z ~ 0.8 from ~1350 galaxies in the Deep Extragalactic Evolutionary Probe 2 (DEEP2) survey. We determine stellar masses by fitting the spectral energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 H. J. Zahid , L. J. Kewley , F. Bresolin

Lithium abundances and rotation, determined for 120 subgiant stars in Lebre et al. (1999) are analyzed. To this purpose, the evolutionary status of the sample as well as the individual masses have been determined using the HIPPARCOS…

Astrophysics · Physics 2007-05-23 J. D. do Nascimento , C. Charbonnel , A. Lebre , P. de Laverny , J. R. De Medeiros

We present unified chemical and spectrophotometric evolutionary synthesis models that allow to describe composite stellar populations in a chemically consistent way. Keeping track of the ISM abundance at birth of each star and using sets of…

Astrophysics · Physics 2020-05-27 U. Fritze-v. Alvensleben

This letter studies the formation of azimuthal metallicity variations in the disks of spiral galaxies in the absence of initial radial metallicity gradients. Using high-resolution $N$-body simulations, we model composite stellar discs, made…

Astrophysics of Galaxies · Physics 2018-03-16 S. Khoperskov , P. Di Matteo , M. Haywood , F. Combes

Dwarf stars with debris discs and planets appear to be excellent laboratories to study the core accretion theory of planets formation. These systems are however, insufficiently studied. In this paper we present the main metallicity and…

Solar and Stellar Astrophysics · Physics 2019-06-12 C. Chavero , R. de la Reza , L. Ghezzi , F. Llorente de Andrés , C. B. Pereira , C. Giuppone , G. Pinzón , .

We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. In this work we present new determinations of lithium abundances for 326 Main Sequence stars with and…

We have carried out a high resolution spectroscopic survey of the 220-250 Myr old cluster NGC 6475: our main purpose is to investigate Li evolution during the early stages of the Main Sequence. We have determined Li abundances for 33 late F…

Astrophysics · Physics 2009-11-07 Paola Sestito , Sofia Randich , Jean-Claude Mermilliod , Roberto Pallavicini

Stars in disks of spiral galaxies are usually assumed to remain roughly at their birth radii. This assumption is built into decades of modelling of the evolution of stellar populations in our own Galaxy and in external systems. We present…

HST trigonometric distances, photometric metallicities, isochronic ages from the second revised version of the Geneva--Copenhagen survey, and uniform spectroscopic Fe and Mg abundances from our master catalog are used to construct and…

Astrophysics of Galaxies · Physics 2015-05-28 V. A. Marsakov , V. V. Koval' , T. V. Borkova , M. V. Shapovalov

The "stellar" solution to the cosmological lithium problem proposes that surface depletion of lithium in low-mass, metal-poor stars can reconcile the lower abundances found for Galactic halo stars with the primordial prediction. Globular…

Solar and Stellar Astrophysics · Physics 2015-05-18 K. Lind , F. Primas , C. Charbonnel , F. Grundahl , M. Asplund
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