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Related papers: The solar nitrogen abundance under the LTE assumpt…

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We review our current knowledge of the solar chemical composition as determined from photospheric absorption lines. In particular we describe the recent significant revisions of the solar abundances as a result of the application of a…

Astrophysics · Physics 2015-06-24 Martin Asplund , Nicolas Grevesse , Jacques Sauval

The generally adopted value for the solar abundance of indium is over six times higher than the meteoritic value. We address this discrepancy through numerical synthesis of the 451.13 nm line on which all indium abundance studies are based,…

Astrophysics · Physics 2009-11-13 N. Vitas , I. Vince , M. Lugaro , O. Andriyenko , M. Gosic , R. J. Rutten

The recent downward revision of the solar photospheric abundances now leads to severe inconsistencies between the theoretical predictions for the internal structure of the Sun and the results of helioseismology. There have been claims that…

Astrophysics · Physics 2009-11-13 T. Morel , K. Butler

An extremely high-resolution (> 10^5) high-S/N (> 10^3) solar spectrum has been used to measure 15 very weak first overtone (Delta v = 2) infrared OH lines, resulting in a low solar abundance of A(O) ~ 8.6 when MARCS, 3D, and spatially and…

Astrophysics · Physics 2009-11-10 Jorge Melendez

We report on the determination of the lithium abundance [A(Li)] of 52 solar-like stars. For 41 objects the A(Li) here presented corresponds to the first measurement. We have measured the equivalent widths of the 6708\AA\ lithium feature in…

Solar and Stellar Astrophysics · Physics 2015-07-07 R. López-Valdivia , J. B. Hernández-Águila , E. Bertone , M. Chávez , F. Cruz-Saenz de Miera , E. M. Amazo-Gómez

Photospheric C, N, and O abundances of 118 solar-analog stars were determined by applying the synthetic-fitting analysis to their spectra in the blue or near-UV region comprising lines of CH, NH, and OH molecules, with an aim of clarifying…

Solar and Stellar Astrophysics · Physics 2023-02-01 Yoichi Takeda

Photospheric parameters and abundances are presented for a sample of single-lined chromospherically active binaries from a differential LTE analysis of high-resolution spectra. Abundances have been derived for 13 chemical species, including…

Astrophysics · Physics 2009-11-10 T. Morel , G. Micela , F. Favata , D. Katz , I. Pillitteri

Neutral nickel (Ni I) is abundant in the solar atmosphere and is one of the important elements that contribute to the emission and absorption of radiation in the spectral range between 1900 and 3900 A. Previously, the Solar Radiation…

Solar and Stellar Astrophysics · Physics 2015-06-15 Mariela C. Vieytes , Juan M. Fontenla

Following our solar work, we perform NLTE calculations of the Mn abundance for fourteen stars with [Fe/H] from 0 to -2.5, mainly to show how NLTE affects Mn abundances in cool stars of different metallicities.The spectrum synthesis and Mn…

Astrophysics · Physics 2009-11-13 Maria Bergemann , Thomas Gehren

We present solar photospheric abundances for 12 elements from optical and near-infrared spectroscopy. The abundance analysis was conducted employing 3D hydrodynamical (CO5BOLD) as well as standard 1D hydrostatic model atmospheres. We…

Solar and Stellar Astrophysics · Physics 2015-05-14 H. -G. Ludwig , E. Caffau , M. Steffen , P. Bonifacio , B. Freytag , R. Cayrel

A representative sample of unevolved early B-type stars in nearby OB associations and the field is analysed to unprecedented precision using NLTE techniques. The resulting chemical composition is found to be more metal-rich and much more…

Astrophysics · Physics 2009-11-13 Norbert Przybilla , Maria-Fernanda Nieva , Keith Butler

The standard solar model was so reliable that it could predict the existence of the massive neutrino. Helioseismology measurements were so precise that they could determine the depth of the convection zone. This agreement between theory and…

Astrophysics · Physics 2009-11-13 J. T. Schmelz , K. Nasraoui , J. K. Roames , L. A. Lippner , J. W. Garst

We report on the determination of chemical abundances of 38 solar analogues, including 11 objects previously identified as super metal-rich stars. We have measured the equivalent widths for 34 lines of 7 different chemical elements (Mg, Al,…

Solar and Stellar Astrophysics · Physics 2017-02-08 Ricardo López-Valdivia , Emanuele Bertone , Miguel Chávez

Branching fraction measurements from Fourier transform spectra in conjunction with published radiative lifetimes are used to determine transition probabilities for 263 lines of neutral chromium. These laboratory values are employed to…

Astrophysics · Physics 2009-11-13 Jennifer S. Sobeck , James E. Lawler , Christopher Sneden

The present-day abundance of beryllium in the solar atmosphere provides clues about mixing mechanisms within stellar interiors. However, abundance determinations based on the Be II 313.107 nm line are prone to systematic errors due to…

Solar and Stellar Astrophysics · Physics 2024-09-09 A. M. Amarsi , D. Ogneva , G. Buldgen , N. Grevesse , Y. Zhou , P. S. Barklem

Solar oxygen abundance measurements based on the O I near-infrared triplet have been a much-debated subject for several decades since non-local thermodynamic equilibrium (NLTE) calculations with 3D radiation-hydrodynamics model atmospheres…

Solar and Stellar Astrophysics · Physics 2023-04-12 A. G. M. Pietrow , R. Hoppe , M. Bergemann , F. Calvo

Determining the He/H ratio in cool stars presents a fundamental astrophysical challenge. While this ratio is established for hot O and B stars, its extrapolation to cool stars remains uncertain due to the absence of helium lines in their…

Solar and Stellar Astrophysics · Physics 2024-10-29 Satyajeet Moharana , B. P. Hema , Gajendra Pandey

Monte Carlo calculations of the Ne K$\alpha$ line fluoresced by coronal x-rays and emitted near the temperature minimum region of the solar atmosphere have been employed to investigate the use of this feature to measure directly the solar…

Astrophysics · Physics 2009-11-13 Jeremy J. Drake , Barbara Ercolano

We propose a line list that may be useful for the abundance analysis of G-type stars in the wavelength range 4080 -- 6780 A. It is expected that the line list will be useful for surveys/libraries with overlapping spectral regions (e.g.…

Solar and Stellar Astrophysics · Physics 2023-10-09 T. Sahin , M. Marismak , N. Cinar , S. Bilir

For the first time, neon abundance has been derived in the narrow line region from a sample of Seyfert~2 nuclei. In view of this, we compiled from the literature fluxes of optical and infrared (IR) narrow emission lines for 35 Seyfert 2…

Astrophysics of Galaxies · Physics 2021-09-22 Mark Armah , O. L. Dors , C. P. Aydar , M. V. Cardaci , G. F. Hagele , Anna Feltre , R. Riffel , R. A. Riffel , A. C. Krabbe