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Related papers: Line-depth ratios as indicators of effective tempe…

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Deriving the metallicity, [Fe/H], in low-resolution spectra of carbon-enhanced metal-poor (CEMP) stars is a tedious task that, owing to the large number of line blends, often leads to uncertainties on [Fe/H] exceeding 0.25dex. The CEMP…

Solar and Stellar Astrophysics · Physics 2020-02-12 D. Singh , C. J. Hansen , J. S. Byrgesen , M. Reichert , H. M. Reggiani

We present atmospheric parameters for about 300 stars of different chemical composition, whose spectra will be used to study the galactic enrichment of Fe and light elements. These parameters were derived using an homogenous iterative…

Astrophysics · Physics 2007-05-23 R. G. Gratton , E. Carretta , F. Castelli

We present a grid of synthetic profiles of stellar H Balmer and HeI lines at optical wavelengths with a sampling of 0.3 A. The grid spans a range of effective temperature 4000 K < Teff < 50000 K, and gravity 0.0 < log g < 5.0 at solar…

Astrophysics · Physics 2009-10-31 Rosa M. Gonzalez Delgado , Claus Leitherer

We are now in an era of large spectroscopic surveys of OB-type stars. Quantitative spectroscopic analysis of these modern datasets is enabling us to review the physical properties of blue massive stars with robust samples, not only…

Solar and Stellar Astrophysics · Physics 2014-10-22 S. Simón-Díaz , A. Herrero , C. Sabín-Sanjulián , F. Najarro , M. Garcia , J. Puls , N. Castro , C. J. Evans

High-resolution, near-infrared spectra will be the primary tool for finding and characterizing Earth-like planets around low-mass stars. Yet, the properties of exoplanets can not be precisely determined without accurate and precise…

We aimed to assess the accuracy of the Gaia teff and logg estimates as derived with current models and observations. We assessed the validity of several inference techniques for deriving the physical parameters of ultra-cool dwarf stars. We…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Luis M. Sarro , Angel Berihuete , Cesar Carrion , David Barrado , Patricia Cruz , Yago Isasi

Aims: The precise determination of the stellar effective temperature of solar type stars is of extreme importance for Astrophysics. We present an effective temperature calibration for FGK dwarf stars using line equivalent width ratios of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 S. G. Sousa , A. Alapini , G. Israelian , N. C. Santos

Identification of metal-poor stars among field stars is extremely useful for studying the structure and evolution of the Galaxy and of external galaxies. We search for metal-poor stars using the artificial neural network (ANN) and extend…

Solar and Stellar Astrophysics · Physics 2015-06-16 Sunetra Giridhar , Aruna Goswami , Andrea Kunder , S. Muneer , G. Selvakumar

Knowledge of stellar atmospheric parameters ($T_{\rm eff}$, $\log{g}$, [Fe/H]) of M dwarfs can be used to constrain both theoretical stellar models and Galactic chemical evolutionary models, and guide exoplanet searches, but their…

Solar and Stellar Astrophysics · Physics 2023-02-22 C. Duque-Arribas , D. Montes , H. M. Tabernero , J. A. Caballero , J. Gorgas , E. Marfil

The spectrum of the Fe I atom is critical to many areas of astrophysics and beyond. Measurements of the energies of its high-lying levels remain woefully incomplete, however, despite extensive analysis of ultraviolet laboratory iron…

Solar and Stellar Astrophysics · Physics 2015-06-19 Ruth C. Peterson , Robert L. Kurucz

The study of stellar parameters of planet-hosting stars, such as metallicity and chemical abundances, help us to understand the theory of planet formation and stellar evolution. Here, we present a catalogue of accurate stellar atmospheric…

Solar and Stellar Astrophysics · Physics 2015-03-11 S. Alves , L. Benamati , N. C. Santos , V. Zh. Adibekyan , S. G. Sousa , G. Israelian , J. R. De Medeiros , C. Lovis , S. Udry

Classification of stars, by comparing their optical spectra to a few dozen spectral standards, has been a workhorse of observational astronomy for more than a century. Here, we extend this technique by compiling a library of optical spectra…

Solar and Stellar Astrophysics · Physics 2017-02-15 Samuel W. Yee , Erik A. Petigura , Kaspar von Braun

It is still being debated whether the well-known metallicity - giant planet correlation for dwarf stars is also valid for giant stars. For this reason, having precise metallicities is very important. Different methods can provide different…

Earth and Planetary Astrophysics · Physics 2015-06-16 A. Mortier , N. C. Santos , S. G. Sousa , V. Zh. Adibekyan , E. Delgado Mena , M. Tsantaki , G. Israelian , M. Mayor

We determine Mg abundances in 6 Gaia benchmark stars using theoretical one-dimensional (1D) hydrostatic model atmospheres, as well as temporally- and spatially-averaged 3D model atmospheres (<3D>). The stars cover a range of Teff from 4700…

Solar and Stellar Astrophysics · Physics 2017-09-27 Maria Bergemann , Remo Collet , Anish M. Amarsi , Mikhail Kovalev , Gregory Ruchti , Zazralt Magic

A comprehensive model atom for Fe with more than 3000 energy levels is presented. As a test and first application of this model atom, Fe abundances are determined for the Sun and five stars with well determined stellar parameters and…

Solar and Stellar Astrophysics · Physics 2015-05-27 L. Mashonkina , T. Gehren , J. -R. Shi , A. J. Korn , F. Grupp

In this study, photometric metallicity and absolute magnitude calibrations were derived using F-G spectral type main-sequence stars in the Solar neighbourhood with precise spectroscopic, photometric and Gaia astrometric data for UBV…

Astrophysics of Galaxies · Physics 2019-10-23 M. Celebi , S. Bilir , S. Ak , T. Ak , Z. F. Bostanci , T. Yontan

In order to accurately determine stellar properties, knowledge of the effective temperature of stars is vital. We implement Gaia and 2MASS photometry in the InfraRed Flux Method and apply it to over 360,000 stars across different…

Context: The full spectrum fitting of stellar spectra against a library of empirical spectra is a well-established approach to measure the atmospheric parameters of FGK stars with a high internal consistency. Extending it towards cooler…

Solar and Stellar Astrophysics · Physics 2015-12-17 Kaushal Sharma , Philippe Prugniel , Harinder P. Singh

Using the near-infrared spectral stellar library of Cenarro et al. (2001a,b), the behaviours of the Mg I line at 8807 angstrom and nearby TiO bands are analyzed in terms of the effective temperature, surface gravity, and metallicity of the…

Astrophysics of Galaxies · Physics 2015-05-13 A. Javier Cenarro , Nicolas Cardiel , Alexandre Vazdekis , Javier Gorgas

NLTE line formation calculations of FeI in the solar atmosphere are extended to include weak optical lines. Previously established atomic models are used to discriminate between different ways of treating collisional interaction processes.…

Astrophysics · Physics 2009-11-07 T. Gehren , A. J. Korn , J. Shi
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