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

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We present a new determination of the solar nitrogen abundance making use of 3D hydrodynamical modelling of the solar photosphere, which is more physically motivated than traditional static 1D models. We selected suitable atomic spectral…

Solar and Stellar Astrophysics · Physics 2010-11-22 E. Maiorca , E. Caffau , P. Bonifacio , M. Busso , R. Faraggiana , M. Steffen , H. -G. Ludwig , I. Kamp

Nitrogen is an important element in various fields of stellar and Galactic astronomy, and the solar nitrogen abundance is crucial as a yardstick for comparing different objects in the cosmos. In order to obtain a precise and accurate value…

Solar and Stellar Astrophysics · Physics 2020-04-29 A. M. Amarsi , N. Grevesse , J. Grumer , M. Asplund , P. S. Barklem , R. Collet

Carbon, nitrogen, and oxygen are the fourth, sixth, and third most abundant elements in the Sun. Their abundances remain hotly debated due to the so-called solar modelling problem that has persisted for almost $20$ years. We revisit this…

Solar and Stellar Astrophysics · Physics 2021-12-11 A. M. Amarsi , N. Grevesse , M. Asplund , R. Collet

CONTEXT: In recent years, the solar chemical abundances have been studied in considerable detail because of discrepant values of solar metallicity inferred from different indicators, i.e., on the one hand, the "sub-solar" photospheric…

Solar and Stellar Astrophysics · Physics 2015-05-13 E. Caffau , E. Maiorca , P. Bonifacio , R. Faraggiana , M. Steffen , H. -G. Ludwig , I. Kamp , M. Busso

We study the solar photospheric abundance of singly ionized neodymium (Nd II) using high resolution spectroscopic data obtained by Fourier transform spectrograph (FTS). Based on the Local Thermodynamical Equilibrium (LTE) assumption, a new…

Solar and Stellar Astrophysics · Physics 2017-12-20 A. G. A. Abdelkawy , Abdelrazek M. K. Shaltout , M. M. Beheary , A. Bakry

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

A new model atom of nitrogen was developed using the energy levels of N I from laboratory measurements and also predicted in atomic structure calculations and the most up-to-date atomic data for computing radiative and collisional rates of…

Solar and Stellar Astrophysics · Physics 2024-06-18 L. I. Mashonkina , T. A. Ryabchikova

We present a detailed spectroscopic analysis of nitrogen abundances in 91 solar-type stars, 66 with and 25 without known planetary mass companions. All comparison sample stars and 28 planet hosts were analysed by spectral synthesis of the…

Astrophysics · Physics 2016-08-16 A. Ecuvillon , G. Israelian , N. C. Santos , M. Mayor , R. J. García López , S. Randich

Motivated by the controversy over the surface metallicity of the Sun, we present a re-analysis of the solar photospheric oxygen (O) abundance. New atomic models of O and Ni are used to perform Non-Local Thermodynamic Equilibrium (NLTE)…

The solar argon abundance cannot be directly derived by spectroscopic observations of the solar photosphere. The solar Ar abundance is evaluated from solar wind measurements, nucleosynthetic arguments, observations of B stars, HII regions,…

Astrophysics · Physics 2009-11-13 Katharina Lodders

The Oxygen abundance in the solar photosphere, and consequently the solar metallicity itself, is still a controversial issue with far-reaching implications in many areas of Astrophysics. This paper presents a new determination obtained by…

Solar and Stellar Astrophysics · Physics 2015-04-29 H. Socas-Navarro

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

We obtained new quantitative determinations of the nitrogen abundance and a consistent relation between nitrogen and oxygen abundances for a sample of Seyfert 2 galaxies located at redshift $z < 0.1$. We carried out this analysis using the…

Astrophysics of Galaxies · Physics 2017-04-19 O. L. Dors , K. Z. Arellano-Cordova , M. V. Cardaci , G. F. Hagele

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 present a detailed NLTE analysis of 39 MnI lines in the solar spectrum. The influence of NLTE effects on the line formation and element abundance is investigated. Our goal is the derivation of solar log gfe values for manganese lines,…

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

Using realistic hydrodynamical simulations of the solar surface convection as 3D, time-dependent, inhomogeneous model atmospheres, the solar photospheric Si abundance has been determined to be log Si = 7.51 +- 0.04. This constitutes a…

Astrophysics · Physics 2008-11-26 M. Asplund

We have evolved a series of thirteen complete solar models that utilize different assumed heavy element compositions. Models that are based upon the heavy element abundances recently determined by Asplund, Grevesse, and Sauval (2005) are…

Astrophysics · Physics 2009-11-10 John N. Bahcall , Sarbani Basu , Aldo M. Serenelli

In this work, we investigated the nitrogen and oxygen abundances in a sample of galaxies with Low Ionization Nuclear Emission Regions (LINERs) in their nucleus. Optical spectroscopic data (3 600 - 10 000 {\AA}) of 40 LINERs from the Mapping…

The solar chemical composition is an important ingredient in our understanding of the formation, structure and evolution of both the Sun and our solar system. Furthermore, it is an essential reference standard against which the elemental…

Solar and Stellar Astrophysics · Physics 2014-11-20 Martin Asplund , Nicolas Grevesse , A. Jacques Sauval , Pat Scott

The abundance of iron is measured from emission line complexes at 6.65 keV (Fe line) and 8 keV (Fe/Ni line) in {\em RHESSI} X-ray spectra during solar flares. Spectra during long-duration flares with steady declines were selected, with an…

Solar and Stellar Astrophysics · Physics 2015-06-03 K. J. H. Phillips , B. R. Dennis
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