English
Related papers

Related papers: Photometric Abundances for G-Dwarfs: A Cautionary …

200 papers

We used the data of 701 stars covering the colour index interval 0.32<B-V<=1.16, with metallicities -1.76<=[Fe/H]<=+0.40 dex, which were taken from PASTEL catalogue and estimated metallicity dependent guillotine factors which provide a more…

Astrophysics of Galaxies · Physics 2015-05-27 S. Karaali , S. Bilir , S. Ak , E. Yaz , B. Coskunoglu

The relativley large spread in the derived metallicities ([Fe/H]) of M dwarfs shows that various approaches have not yet converged to consistency. The presence of strong molecular features, and incomplete line lists for the corresponding…

Solar and Stellar Astrophysics · Physics 2015-06-03 Anna Önehag , Ulrike Heiter , Bengt Gustafsson , Nikolai Piskunov , Bertrand Plez , Ansgar Reiners

Photometric metallicity formulae of fundamental-mode RR Lyr (RRab) stars are presented using globular-cluster data exclusively. The aim is to check whether this selection may help increasing the overall accuracy of the fits and eliminating…

Solar and Stellar Astrophysics · Physics 2023-08-21 Johanna Jurcsik , Gergely Hajdu

We present new empirical and theoretical calibrations of two photometric metallicity indices based on Walraven photometry. The empirical calibration relies on a sample of 48 Cepheids for which iron abundances based on high resolution…

(Abriged) A new grid of theoretical color indices for the Stromgren uvby photometric system has been derived from MARCS model atmospheres and SSG synthetic spectra for cool dwarf and giant stars. At warmer temperatures this grid has been…

Astrophysics · Physics 2009-11-10 J. L. Clem , D. A. VandenBerg , F. Grundahl , R. A. Bell

The accretion of rocky material is responsible for the presence of heavy elements in the atmospheres of a large fraction of white dwarf stars. Those objects represent a unique opportunity to infer the bulk composition of exoplanetesimals.…

Solar and Stellar Astrophysics · Physics 2020-09-11 Simon Blouin

We determine magnesium isotopic abundances of metal poor dwarf stars from the galactic halo, to shed light on the onset of asymptotic giant branch (AGB) star nucleossynthesis in the galactic halo and constrain the timescale of its…

Solar and Stellar Astrophysics · Physics 2018-04-18 Marilia Carlos , Amanda I. Karakas , Judith G. Cohen , Chiaki Kobayashi , Jorge Melendez

From an initial sample of a few hundred stars selected for an Hipparcos program, a subsample of 33 objects with direct determination of their effective temperature, bolometric magnitude and [Fe/H] has been derived. An accurate observational…

Astrophysics · Physics 2007-05-23 Y. Lebreton , M. -N. Perrin , R. Cayrel , A. Baglin , J. Fernandes

Nine metal-polluted white dwarfs are observed with medium-resolution optical spectroscopy,where photospheric abundances are determined and interpreted through comparison against solar system objects. An improved method of making such…

Earth and Planetary Astrophysics · Physics 2019-10-09 Andrew Swan , Jay Farihi , Detlev Koester , Mark Hollands , Steven Parsons , P. Wilson Cauley , Seth Redfield , Boris T. Gaensicke

The age-metallicity relation of the solar neighbourhood is studied using a sample of 552 late-type dwarfs. This sample was built from the intersection of photometric catalogues with chromospheric activity surveys of the Mount Wilson group.…

Astrophysics · Physics 2007-05-23 H. J. Rocha-Pinto , W. J. Maciel , John Scalo , Chris Flynn

We analysed red giant branch stars in 16 Galactic globular clusters, computing their atmospheric parameters both from the photometry and from excitation and ionisation balances. The spectroscopic parameters are lower than the photometric…

Solar and Stellar Astrophysics · Physics 2020-08-26 A. Mucciarelli , P. Bonifacio

We compare the metallicities of stars with radial velocity planets to the metallicity of a sample of field dwarfs. We confirm recent work indicating that the stars-with-planet sample as a whole is iron rich. However, the lowest mass stars…

Astrophysics · Physics 2009-11-06 N. Murray , B. Chaboyer

We present a new fully data-driven algorithm that uses photometric data from the Canada-France-Imaging-Survey (CFIS; $u$), Pan-STARRS 1 (PS1; $griz$), and Gaia ($G$) to discriminate between dwarf and giant stars and to estimate their…

Using standard 1D-LTE model atmosphere analysis, we provide an in-depth investigation of iron abundance as derived from neutral and singly ionization iron lines (Fe {\scriptsize{I, II}}) in nearby star clusters. Specifically, we replicate…

Solar and Stellar Astrophysics · Physics 2017-09-06 Patrick D. Aleo , Alexander C. Sobotka , Ivan Ramirez

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 determine the iron distribution function (IDF) for bulge field stars, in three different fields along the Galactic minor axis and at latitudes b=-4 deg, b=-6 deg, and b=-12 deg. A fourth field including NGC6553 is also included in the…

Astrophysics · Physics 2011-05-18 M. Zoccali , V. Hill , A. Lecureur , B. Barbuy , A. Renzini , D. Minniti , A. Gomez , S. Ortolani

The fraction of binary stars (fb) is one of most valuable tool to probe the star formation and evolution of multiple systems in the Galaxy. We focus on the relationship between fb and stellar metallicity ([Fe/H]) by employing the…

Solar and Stellar Astrophysics · Physics 2017-05-31 Shuang Gao , He Zhao , Hang Yang , Ran Gao

(Abridged) We investigate the effects of metallicity on the broad-band photometric colors of late-type giants, and make a comparison of synthetic colors with observed photometric properties of late-type giants over a wide range of effective…

Astrophysics · Physics 2009-11-11 A. Kucinskas , P. H. Hauschildt , I. Brott , V. Vansevicius , L. Lindegren , T. Tanabe , F. Allard

The concomitant overabundances of C, N and s-process elements are commonly ascribed to the complex interplay of nucleosynthesis, mixing and mass loss taking place in Asymptotic Giant Branch stars. At low metallicity, the enhancement of C…

Astrophysics · Physics 2011-02-11 S. Cristallo , O. Straniero , M. T. Lederer , B. Aringer

We determine a K-band luminosity-metallicity (K-Z) relation for dwarf irregular galaxies, over a large range of magnitudes, -20.5 < M_K < -13.5, using a combination of K photometry from either the 2-micron all sky survey (2MASS) or the…

‹ Prev 1 4 5 6 7 8 10 Next ›