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Related papers: Another forbidden solar oxygen abundance: the [O I…

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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

An extremely high-resolution (> 10^5) high-S/N (> 10^3) solar spectrum has been used to measure 15 very weak first overtone (Delta v = 2) infrared OH lines, resulting in a low solar abundance of A(O) ~ 8.6 when MARCS, 3D, and spatially and…

Astrophysics · Physics 2009-11-10 Jorge Melendez

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

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 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

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 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

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

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 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

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

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

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 debate on the oxygen abundances of metal-poor stars has its origin in contradictory results obtained using different abundance indicators. To achieve a better understanding of the problem we have acquired high quality spectra with the…

Astrophysics · Physics 2016-08-16 A. E. García Pérez , M. Asplund , F. Primas , P. E. Nissen , B. Gustafsson

Oxygen is a powerful tracer element of Galactic chemical evolution. Unfortunately, only a few oxygen lines are available in the ultraviolet-infrared stellar spectra for the reliable determination of its abundance. Moreover, oxygen…

Solar and Stellar Astrophysics · Physics 2014-09-11 A. Kucinskas , V. Dobrovolskas , P. Bonifacio , E. Caffau , H. -G. Ludwig , M. Steffen , M. Spite

The solar abundances have undergone a major downward revision in the last decade, reputedly as a result of employing 3D hydrodynamical simulations to model the inhomogeneous structure of the solar photosphere. The very low oxygen abundance…

Solar and Stellar Astrophysics · Physics 2009-10-27 E. Caffau , H. -G. Ludwig , M. Steffen

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 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 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

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
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