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Related papers: The 'Forbidden' Abundance of Oxygen in the Sun

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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

The solar photospheric abundance of oxygen is still a matter of debate. For about ten years some determinations have favoured a low oxygen abundance which is at variance with the value inferred by helioseismology. Among the oxygen abundance…

Solar and Stellar Astrophysics · Physics 2015-07-15 E. Caffau , H. -G. Ludwig , M. Steffen , W. Livingston , P. Bonifacio , J. -M. Malherbe , H. -P. Doerr , W. Schmidt

Context: Recent works with improved model atmospheres, line formation, atomic and molecular data, and detailed treatment of blends, have resulted in a significant downward revision of the solar oxygen abundance. Aims: Considering the…

Astrophysics · Physics 2009-11-13 Jorge Melendez , Martin Asplund

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

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)…

We have measured the oscillator strength of the Ni I line at 6300.34 \AA, which is known to be blended with the forbidden [O I] $\lambda$6300 line, used for determination of the oxygen abundance in cool stars. We give also wavelengths of…

Astrophysics · Physics 2016-08-16 S. Johansson , U. Litzén , H. Lundberg , Z. Zhang

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

We report on the detection of linear polarization of the forbidden [O i] 630.03 nm spectral line. The observations were carried out in the broader context of the determination of the solar oxygen abundance, an important problem in…

Solar and Stellar Astrophysics · Physics 2021-02-03 A. G. de Wijn , H. Socas-Navarro , N. Vitas

In this work we present new data that sets strong constraints on the solar oxygen abundance. Our approach, based on the analysis of spectro-polarimetric observations, is almost model-independent and therefore extremely robust. The asymmetry…

Astrophysics · Physics 2009-11-13 R. Centeno , H. Socas-Navarro

In the Sun, the two forbidden [OI] lines at 630 and 636 nm were previously found to provide discrepant oxygen abundances. aims: We investigate whether this discrepancy is peculiar to the Sun or whether it is also observed in other stars.…

Solar and Stellar Astrophysics · Physics 2015-06-15 Elisabetta Caffau , Hans-G. Ludwig , Jean-M. Malherbe , Piercarlo Bonifacio , Matthias Steffen , Lorenzo Monaco

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

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

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…

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

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

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

We present oxygen abundances for 72 F and G dwarf stars in the solar neighbourhood. Using the kinematics of the stars we divide them into two sub-samples with space velocities that are typical for the thick and thin disks, respectively. The…

Astrophysics · Physics 2009-11-10 T. Bensby , S. Feltzing , I. Lundstrom

The abundance of oxygen was determined for selected very metal-poor G-K stars (six giants and one turn-off star) based on the high S/N and high-resolution spectra observed with Keck HIRES in the red through near-IR region comprising the…

Astrophysics · Physics 2007-05-23 Y. Takeda , M. Takada-Hidai , S. Sato , W. L. W. Sargent , L. Lu , T. A. Barlow , J. Jugaku

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 determination of the solar oxygen abundance remains a central problem in astrophysics, as its accuracy is limited not only by models but also by systematics. While many of these factors have been thoroughly characterized, the effect of…

Solar and Stellar Astrophysics · Physics 2026-02-11 A. G. M. Pietrow , M. Baratella , I. V. Ilyin , M. Steffen , K. G. Strassmeier
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