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

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The knowledge of isotopic and elemental abundances of the pristine solar system material provides a fundamental test of galactic chemical evolution models, while the composition of the solar photosphere is a reference pattern to understand…

Astrophysics · Physics 2009-11-11 L. Piersanti , O. Straniero , S. Cristallo

We derive the nitrogen and oxygen abundances in the Narrow Line Regions (NLRs) of a sample of 38 local ($z \: < \: 0.4$) Seyfert~2 nuclei. For that, we consider narrow optical emission line intensities and direct estimates of the electron…

The influence of departures from local thermodynamic equilibrium (LTE) on neutral sulfur lines is considered. A grid of corrections is proposed to take into account the influence of departures from LTE for neutral sulfur lines in the…

Solar and Stellar Astrophysics · Physics 2025-03-18 S. A. Korotin , K. O. Kiselev

Estimates of the bulk metal abundance of the Sun derived from the latest generation of model atmospheres are significantly lower than the earlier standard values. In Paper I we demonstrated that a low solar metallicity is inconsistent with…

Astrophysics · Physics 2009-10-06 M. H. Pinsonneault , Franck Delahaye

The solar photospheric oxygen abundance has been determined from [OI], OI, OH vibration-rotation and OH pure rotation lines by means of a realistic time-dependent, 3D, hydrodynamical model of the solar atmosphere. In the case of the OI…

Astrophysics · Physics 2009-07-09 M. Asplund , N. Grevesse , A. J. Sauval , C. Allende Prieto , D. Kiselman

In this work, we present a photospheric solar silicon abundance derived using CO5BOLD model atmospheres and the LINFOR3D spectral synthesis code. Previous works have differed in their choice of a spectral line sample and model atmosphere as…

Solar and Stellar Astrophysics · Physics 2022-12-16 S. A. Deshmukh , H. -G. Ludwig , A. Kučinskas , M. Steffen , P. S. Barklem , E. Caffau , V. Dobrovolskas , P. Bonifacio

In the last decade, the photospheric solar metallicity as determined from spectroscopy experienced a remarkable downward revision. Part of this effect can be attributed to an improvement of atomic data and the inclusion of NLTE…

Solar and Stellar Astrophysics · Physics 2015-05-18 Elisabetta Caffau , Hans-Günter Ludwig , Matthias Steffen , Bernd Freytag , Piercarlo Bonifacio

We investigate the formation of neutral and singly ionized scandium lines in the solar photospheres. The research is aimed derive solar $\log gf\epsilon_{\odot}$(Sc) values for scandium lines, which will later be used in differential…

Astrophysics · Physics 2008-02-20 H. W. Zhang , T. Gehren , G. Zhao

We present three-dimensional (3D) non-local thermodynamic equilibrium (non-LTE) radiative transfer calculations for silicon in the solar photosphere, using an extensive model atom that includes recent, realistic neutral hydrogen collisional…

Solar and Stellar Astrophysics · Physics 2016-09-28 A. M. Amarsi , M. Asplund

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

Accurately known stellar lithium abundances may be used to shed light on a variety of astrophysical phenomena such as Big Bang nucleosynthesis, radial migration, ages of stars and stellar clusters, and planet engulfment events. We present a…

Solar and Stellar Astrophysics · Physics 2020-10-30 E. Wang , T. Nordlander , M. Asplund , A. M. Amarsi , K. Lind , Y. Zhou

Aims. We report the results of a novel determination of the solar oxygen abundance using spatially resolved observations and inversions. We seek to derive the photospheric solar oxygen abundance with a method that is robust against…

Solar and Stellar Astrophysics · Physics 2020-11-18 Melania Cubas Armas , Andrés Asensio Ramos , Héctor Socas-Navarro

Accurate determination of photospheric solar abundances requires detailed modeling of the solar granulation and accounting for departures from local thermodynamical equilibrium (LTE). We argue that the forbidden C I line at 8727 A is…

Astrophysics · Physics 2009-11-07 Carlos Allende Prieto , David L. Lambert , Martin Asplund

We re-evaluate the abundances of the elements in the Sun from copper ($Z=29$) to thorium ($Z=90$). Our results are mostly based on neutral and singly-ionised lines in the solar spectrum. We use the latest 3D hydrodynamic solar model…

Solar and Stellar Astrophysics · Physics 2014-12-17 Nicolas Grevesse , Pat Scott , Martin Asplund , A. Jacques Sauval

The infrared (IR) range is extremely useful in the context of chemical abundance studies of the gas-phase interstellar medium (ISM) due to the large variety of ionic species traced in this regime, the negligible effects from dust…

The compositions of stars are a critical diagnostic tool for many topics in astronomy such as the evolution of our Galaxy, the formation of planets, and the uniqueness of the Sun. Previous spectroscopic measurements indicate a large…

The use of hydrodynamical simulations, the selection of atomic data, and the computation of deviations from local thermodynamical equilibrium for the analysis of the solar spectra have implied a downward revision of the solar metallicity.…

Solar and Stellar Astrophysics · Physics 2015-05-18 E. Caffau , H. -G. Ludwig , P. Bonifacio , R. Faraggiana , M. Steffen , B. Freytag , I. Kamp , T. R. Ayres

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

The solar oxygen abundance has undergone a major downward revision in the last decade, the most noticeable one being the update including 3D hydrodynamical simulations to model the solar photosphere. Up to now, such an analysis has been…

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