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

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Aims. We investigate statistical equilibrium of Cr in the atmospheres of late-type stars to show whether the systematic abundance discrepancy between Cr I and Cr II lines, as often encountered in the literature, is due to deviations from…

Solar and Stellar Astrophysics · Physics 2015-05-19 Maria Bergemann , Gabriele Cescutti

It is shown that the metal abundance in the solar interior is constrained from the current solar neutrino experiment, even if one allows neutrino conversion in the sun due to neutrino oscillation. The result shows that the metal abundance…

Astrophysics · Physics 2015-06-24 M. Fukugita , N. Hata

We combine a new Galactic plane survey of Hydrogen Radio Recombination Lines (RRLs) with far-infrared (FIR) surveys of ionized Nitrogen, N+, to determine Nitrogen abundance across Galactic radius. RRLs were observed with NASA DSS-43 70m…

Our ability to model the shapes and strengths of iron lines in the solar spectrum is a critical test of the accuracy of the solar iron abundance, which sets the absolute zero-point of all stellar metallicities. We use an extensive 463-level…

Solar and Stellar Astrophysics · Physics 2017-05-31 K. Lind , A. M. Amarsi , M. Asplund , P. S. Barklem , M. Bautista , M. Bergemann , R. Collet , D. Kiselman , J. Leenaarts , T. M. D. Pereira

This study introduces a line list for the abundance analysis of F and G type stars across the 4080-9675 A wavelength range. A systematic search employing lower excitation potentials, accurate log gf values, and an updated multiplet table…

Solar and Stellar Astrophysics · Physics 2025-01-09 T. Şahin , F. Güney , S. A. Şentürk , N. Çınar , M. Marışmak

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

CO spectral line formation in the Sun has long been a source of consternation for solar physicists, as have the elemental abundances it seems to imply. We modelled solar CO line formation using a realistic, ab initio, time-dependent 3D…

Astrophysics · Physics 2007-05-23 Patrick C. Scott , Martin Asplund , Nicolas Grevesse , A. Jacques Sauval

We compile spectroscopic abundance data from 84 literature sources for 50 elements across 3058 stars in the solar neighborhood, within 150 pc of the Sun, to produce the Hypatia Catalog. We evaluate the variability of the spread in abundance…

Solar and Stellar Astrophysics · Physics 2015-06-19 Natalie R. Hinkel , F. X. Timmes , Patrick A. Young , Michael D. Pagano , Margaret C. Turnbull

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

Silver is an important light neutron-capture element whose stellar abundances help constrain the origin of the weak r-process. The Sun is an important reference point for such studies; moreover, being a moderately volatile element in CI…

Solar and Stellar Astrophysics · Physics 2026-05-08 Sema Caliskan , Anish M. Amarsi , Per Jönsson , Nicolas Grevesse , Bijaya K. Sahoo

Based on detailed 2D radiation hydrodynamics (RHD) simulations, we have investigated the effects of photospheric temperature inhomogeneities induced by convection on spectroscopic determinations of the lithium abundance. Computations have…

Astrophysics · Physics 2007-05-23 R. Cayrel , M. Steffen

The solar photospheric oxygen abundance is still widely debated. Adopting the solar chemical composition based on the "low" oxygen abundance, as determined with the use of three-dimensional (3D) hydrodynamical model atmospheres, results in…

Solar and Stellar Astrophysics · Physics 2016-08-08 M. Steffen , D. Prakapavičius , E. Caffau , H. -G. Ludwig , P. Bonifacio , R. Cayrel , A. Kučinskas , W. C. Livingston

The purpose of this work is to better understand the confidence limits of the photospheric solar oxygen abundance derived from three-dimensional models using the forbidden [OI] line at 6300 \AA , including correlations with other parameters…

Solar and Stellar Astrophysics · Physics 2017-03-29 M. Cubas Armas , A. Asensio Ramos , H. Socas-Navarro

Simultaneous analysis of the C_2 and CN molecular bands in the 5100-5200 and 7930-8100A spectral regions is a promising alternative for the accurate determination of the carbon (C) and nitrogen (N) abundance in the atmospheres of the…

Solar and Stellar Astrophysics · Physics 2022-09-28 T. Ryabchikova , N. Piskunov , Y. Pakhomov

We construct updated solar models with different sets of solar abundances, including the most recent determinations by Asplund et al. (2009). The latter work predicts a larger ($\sim 10%$) solar metallicity compared to previous measurements…

Solar and Stellar Astrophysics · Physics 2011-03-31 Aldo Serenelli , Sarbani Basu , Jason W. Ferguson , Martin Asplund

The Mg/Ne abundance ratio in the quiet Sun is measured in both network and supergranule cell centre regions through EUV spectra from the Coronal Diagnostic Spectrometer on SOHO. Twenty four sets of data over the period 1996 March to 1998…

Astrophysics · Physics 2009-11-10 P. R. Young

Aims: To determine the neon-to-oxygen abundance in the quiet Sun, a proxy for the photospheric abundance ratio. Method: An emission measure method applied to extreme ultraviolet emission lines of Ne IV-VI and O III-V ions observed by the…

Astrophysics · Physics 2009-11-11 P. R. Young

We investigate the discrepancy between oxygen abundance estimations for narrow-line regions (NLRs) of Active Galactic Nuclei (AGNs) type Seyfert 2 derived by using direct estimations of the electron temperature (Te-method) and those derived…

Astrophysics of Galaxies · Physics 2020-07-01 O. L. Dors , R. Maiolino , M. V. Cardaci , G. F. Hagele , A. C. Krabbe , E. Perez-Montero , M. Armah

The present-day phosphorus abundance in the solar neighbourhood is determined from a sample of OB-type stars. This is in order to constrain the endpoint of the galactochemical evolution of phosphorus in the course of stellar nucleosynthesis…

Solar and Stellar Astrophysics · Physics 2025-06-18 P. Aschenbrenner , K. Butler , N. Przybilla

We present a method to determine nitrogen abundance ratios with respect to iron ([N/Fe]) from molecular CN-band features observed in low-resolution ($R \sim$ 2000) stellar spectra obtained by the Sloan Digital Sky Survey (SDSS) and the…

Astrophysics of Galaxies · Physics 2022-05-25 Changmin Kim , Young Sun Lee , Timothy C. Beers , Thomas Masseron
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