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Related papers: Solar abundances and granulation effects

200 papers

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)…

aims: We determine the solar abundance of phosphorus using co5bold 3D hydrodynamic model atmospheres. method: High resolution, high signal-to-noise solar spectra of the PI lines of Multiplet 1 at 1051-1068 nm are compared to line formation…

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

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

Aims: we seek to provide additional tests of the line formation of theoretical 3D solar photosphere models. In particular, we set out to test the spatially-resolved line formation at several viewing angles, from the solar disk-centre to the…

Solar and Stellar Astrophysics · Physics 2015-05-14 Tiago M. D. Pereira , Dan Kiselman , Martin Asplund

We show that standard solar models are in good agreement with the helioseismologically determined sound speed and density as a function of solar radius, the depth of the convective zone, and the surface helium abundance, as long as those…

Astrophysics · Physics 2011-09-29 John N. Bahcall , Sarbani Basu , Marc Pinsonneault , Aldo M. Serenelli

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

In the last decade, the photospheric abundances of the Sun had been revised several times by many observers. The standard solar models (SSM) constructed with the new low-metal abundances disagree with helioseismic results and detected…

Solar and Stellar Astrophysics · Physics 2016-04-27 Wuming Yang

The granulation background seen in the power spectrum of a solar-like oscillator poses a serious challenge for extracting precise and detailed information about the stellar oscillations. Using a 3D hydrodynamical simulation of the Sun…

Solar and Stellar Astrophysics · Physics 2020-12-02 Mia S. Lundkvist , Hans-Günter Ludwig , Remo Collet , Thomas Straus

Due to the high quality constraints available for the Sun, we can carry out combined analyses using neutrino, spectroscopic and helioseismic observations. Such studies lay the ground for future improvements of key physical components of…

The chemical composition of the Sun is among the most important quantities in astrophysics. Solar abundances are needed for modelling stellar atmospheres, stellar structure and evolution, population synthesis, and galaxies as a whole. The…

Solar and Stellar Astrophysics · Physics 2016-07-27 Maria Bergemann , Aldo Serenelli

Recent solar photospheric abundance analyses (Asplund et al. 2004, 2005; Lodders 2003) have revised downward the C, N, O, Ne, and Ar abundances by 0.15 to 0.2 dex compared to previous determinations of Grevesse & Sauval (1998). With these…

Astrophysics · Physics 2009-11-10 J. Guzik , L. S. Watson , A. Cox

A parametric model of granulation employing a small number of parameters was developed. Synthetic spectra calculated using this model closely match observed spectra and, in particular, reproduce the asymmetries observed in spectral lines.…

Solar and Stellar Astrophysics · Physics 2017-08-23 Timo A. Nieminen

Context. The most recent determination of the solar chemical composition, using a time-dependent, 3D hydrodynamical model of the solar atmosphere, exhibits a significant decrease of C, N, O abundances compared to their previous values.…

Astrophysics · Physics 2011-03-28 A. Zaatri , J. Provost , G. Berthomieu , P. Morel , T. Corbard

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

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

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 new generation of 3D hydrodynamical model atmospheres have been employed to study the impact of a realistic treatment of stellar convection on element abundance determinations of globular cluster stars for a range of atomic and…

Astrophysics · Physics 2007-05-23 Martin Asplund

The solar granulation is known for a long time to be a surface manifestation of convection. Thanks to the current space-borne missions CoRoT and Kepler, it is now possible to observe in disk-integrated intensity the signature of this…

Solar and Stellar Astrophysics · Physics 2015-06-17 R. Samadi , K. Belkacem , H. -G. Ludwig

In an effort to estimate the largely unknown effects of photospheric temperature fluctuations on spectroscopic abundance determinations, we have studied the problem of LTE line formation in the inhomogeneous solar photosphere based on…

Astrophysics · Physics 2009-11-07 M. Steffen , H. Holweger