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Related papers: The 3D non-LTE solar nitrogen abundance from atomi…

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Context. The pursuit of more realistic spectroscopic modelling and consistent abundances has led us to begin a new series of papers designed to improve current solar and stellar abundances of various atomic species. To achieve this, we have…

Solar and Stellar Astrophysics · Physics 2020-02-12 A. J. Gallagher , M. Bergemann , R. Collet , B. Plez , J. Leenaarts , M. Carlsson , S. A. Yakovleva , A. K Belyaev

The statistical equilibrium of neutral and ionised silicon in the solar photosphere is investigated. Line formation is discussed and the solar silicon abundance determined. High-resolution solar spectra were used to determine solar $\log…

Astrophysics · Physics 2009-11-13 J. R. Shi , T. Gehren , K. Butler , L. I. Mashonkina , G. Zhao

Different simplified approaches are used to account for the non-local thermodynamic equilibrium (NLTE) effects with 3D hydrodynamical model atmospheres. In certain cases, chemical abundances are derived in 1D NLTE and corrected for the 3D…

Solar and Stellar Astrophysics · Physics 2016-02-17 J. Klevas , A. Kučinskas , M. Steffen , E. Caffau , H. -G. Ludwig

Determinations of the solar oxygen content relying on the neutral forbidden transition at 630 nm depend upon the nickel abundance, due to a Ni I blend. Here we rederive the solar nickel abundance, using the same ab initio 3D hydrodynamic…

Astrophysics · Physics 2009-01-27 Pat Scott , Martin Asplund , Nicolas Grevesse , A. Jacques Sauval

We performed non-LTE calculations for O I with the plane-parallel model atmospheres for a set of stellar parameters corresponding to A-K type stars. The model atom of Przybilla et al. (2000) was updated using the best theoretical and…

Solar and Stellar Astrophysics · Physics 2013-02-06 T. M. Sitnova , L. I. Mashonkina , T. A. Ryabchikova

Our recent re-analysis of the solar photospheric spectra with non-local thermodynamic equilibrium (non-LTE) models resulted in higher metal abundances compared to previous works. When applying the new chemical abundances to Standard Solar…

Solar and Stellar Astrophysics · Physics 2022-09-07 Manuel A. Bautista , Maria Bergemann , Helena Carvajal Gallego , Sébastien Gamrath , Patrick Palmeri , Pascal Quinet

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

A comprehensive model atom was constructed for C I using the most up-to-date atomic data. We evaluated non-local thermodynamical equilibrium (NLTE) line formation for neutral carbon in classical 1D models representing atmospheres of…

Solar and Stellar Astrophysics · Physics 2015-09-09 S. A. Alexeeva , L. I. Mashonkina

To revisit the long-standing problem of possible inconsistency concerning the oxygen composition in the current galactic gas and in the solar atmosphere (i.e., the former being appreciably lower by ~0.3 dex) apparently contradicting the…

Solar and Stellar Astrophysics · Physics 2015-05-19 Yoichi Takeda , Eiji Kambe , Kozo Sadakane , Seiji Masuda

We reexamine closely the solar photospheric line at 6300 A, which is attributed to a forbidden line of neutral oxygen, and is widely used in analyses of other late-type stars. We use a three-dimensional time-dependent hydrodynamical model…

Astrophysics · Physics 2016-08-30 Carlos Allende Prieto , David L. Lambert , Martin Asplund

We constructed a comprehensive model atom for NeI -- NeII using the most up-to-date atomic data available and evaluated the non-local thermodynamic equilibrium (NLTE) line formation for NeI and NeII in classical 1D models representing the…

Solar and Stellar Astrophysics · Physics 2020-06-24 Sofya Alexeeva , Tianxiang Chen , Tatyana Ryabchikova , Weibin Shi , Kozo Sadakane , Masayoshi Nishimura , Gang Zhao

The solar chemical composition is a fundamental yardstick in astrophysics and the topic of heated debate in recent literature. We re-evaluate the abundance of sulphur in the photosphere by studying seven S I lines in the solar disc-centre…

Solar and Stellar Astrophysics · Physics 2025-11-05 A. M. Amarsi , W. Li , N. Grevesse , A. J. G. Jurewicz

The spectral lines of the CH molecule are a key carbon (C) abundance diagnostic in FGKM-type stars. These lines are detectable in metal-rich and, in contrast to atomic C lines, also in metal-poor late-type stars. However, only 3D LTE…

Solar and Stellar Astrophysics · Physics 2026-02-04 Richard Hoppe , Maria Bergemann , Philipp Eitner , Momo Ellwarth , Åke Nordlund , Jorrit Leenaarts , Bertrand Plez , Aldo Serenelli

Context: There is a lively debate about the solar oxygen abundance and the role of 3D models in its recent downward revision. The models have been tested using high resolution solar atlases. Further testing can be done using centre-to-limb…

Solar and Stellar Astrophysics · Physics 2015-05-14 Tiago M. D. Pereira , Martin Asplund , Dan Kiselman

Non-local thermodynamical equilibrium (NLTE) line formation for Mg I and Mg II lines is considered in classical 1D-LTE model atmospheres of the Sun and 17 stars with reliable atmospheric parameters and in a broad range of spectral types:…

Solar and Stellar Astrophysics · Physics 2018-10-31 Sofya Alexeeva , Tatiana Ryabchikova , Lyudmila Mashonkina , Shaoming Hu

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

In this work we present support for recent claims that advocate a downward revision of the solar oxygen abundance. Our analysis employs spatially-resolved spectro-polarimetric observations including the \FeI lines at 6302 \AA and the \OI…

Astrophysics · Physics 2007-05-23 H. Socas-Navarro A. A. Norton

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

Convective motions in solar-type stellar atmospheres induce Doppler shifts that affect the strengths and shapes of spectral absorption lines and create slightly asymmetric line profiles. 1D LTE studies of elemental abundances are not able…

Solar and Stellar Astrophysics · Physics 2018-10-10 G. Harutyunyan , M. Steffen , A. Mott , E. Caffau , G. Israelian , J. I. González Hernández , K. G. Strassmeier

The solar photospheric carbon abundance has been determined from [C I], C I, CH vibration-rotation, CH A-X electronic and C2 Swan electronic lines by means of a time-dependent, 3D, hydrodynamical model of the solar atmosphere. Departures…

Astrophysics · Physics 2009-11-10 M. Asplund , N. Grevesse , A. J. Sauval , C. Allende Prieto , R. Blomme