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Related papers: Chemical Abundances from the Continuum

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In the last decade, the photospheric solar metallicity as determined from spectroscopy experienced a remarkable downward revision. Part of this effect can be attributed to an improvement of atomic data and the inclusion of NLTE…

Solar and Stellar Astrophysics · Physics 2015-05-18 Elisabetta Caffau , Hans-Günter Ludwig , Matthias Steffen , Bernd Freytag , Piercarlo Bonifacio

We review our current knowledge of the solar chemical composition as determined from photospheric absorption lines. In particular we describe the recent significant revisions of the solar abundances as a result of the application of a…

Astrophysics · Physics 2015-06-24 Martin Asplund , Nicolas Grevesse , Jacques Sauval

Computed color indices and spectral shapes for individual stars are routinely compared with observations for essentially all spectral types, but absolute fluxes are rarely tested. We can confront observed irradiances with the predictions…

Astrophysics · Physics 2007-09-17 Carlos Allende Prieto

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

A series of recent studies has placed the best estimates of the photospheric abundances of carbon and oxygen at log epsilon = 8.39 and 8.66, respectively. These values are ~ 40 % lower than earlier estimates. A coalition of corrections due…

Astrophysics · Physics 2007-05-23 Carlos Allende Prieto

We present solar photospheric abundances for 12 elements from optical and near-infrared spectroscopy. The abundance analysis was conducted employing 3D hydrodynamical (CO5BOLD) as well as standard 1D hydrostatic model atmospheres. We…

Solar and Stellar Astrophysics · Physics 2015-05-14 H. -G. Ludwig , E. Caffau , M. Steffen , P. Bonifacio , B. Freytag , R. Cayrel

The chemical composition of the Sun is a fundamental yardstick in astronomy, relative to which essentially all cosmic objects are referenced. We reassess the solar abundances of all 83 long-lived elements, using highly realistic solar…

Solar and Stellar Astrophysics · Physics 2021-09-29 M. Asplund , A. M. Amarsi , N. Grevesse

Helioseismology has shown that the chemical composition of the Sun has changed over its lifetime. The surface abundance of helium and heavy elements is believed to have decreased by up to 10% relative to their initial values. However, this…

Astrophysics · Physics 2015-06-24 S. Turcotte , R. F. Wimmer-Schweingruber

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 chemical composition of the Sun is requested in the context of various studies in astrophysics, among them in the calculation of the standard solar models (SSMs), which describe the evolution of the Sun from the pre-main-sequence to its…

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

The latest solar atmosphere models include non-LTE corrections and 3D hydrodynamic convection simulations. These models predict a significant reduction in the solar metal abundance, which leads to a serious conflict between helioseismic…

Astrophysics · Physics 2008-11-26 Franck Delahaye , Marc Pinsonneault

Context. Europium is an almost pure r-process element, which may be useful as a reference in nucleocosmochronology. Aims. To determine the photospheric solar abundance using CO5BOLD 3-D hydrodynamical model atmospheres. Methods. Disc-centre…

Astrophysics · Physics 2009-11-13 A. Mucciarelli , E. Caffau , B. Freytag , H. -G. Ludwig , P. Bonifacio

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

We explore the effect of the magnetic field when using realistic three-dimensional convection experiments to determine solar element abundances. By carrying out magnetoconvection simulations with a radiation-hydro code (the Copenhagen…

Solar and Stellar Astrophysics · Physics 2015-05-19 D. Fabbian , E. Khomenko , F. Moreno-Insertis , Å. Nordlund

Is the Sun likely to have a more opaque interior than previously thought? The solar oxygen (or abundance) problem can be solved with higher interior opacities, reconciling abundance analyses based on 3D convective atmospheres with the…

Solar and Stellar Astrophysics · Physics 2018-04-12 Regner Trampedach

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…

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

We show that uncertainties in the values of the surface heavy element abundances of the Sun are the largest source of the theoretical uncertainty in calculating the p-p, pep, 8B, 13N, 15O, and 17F solar neutrino fluxes. We evaluate for the…

Astrophysics · Physics 2008-11-26 John N. Bahcall , Aldo M. Serenelli

We investigate the impact on Fe abundance determination of including magnetic flux in series of 3D radiation-MHD simulations of solar convection which we used to synthesize spectral intensity profiles corresponding to disc centre. A…

Solar and Stellar Astrophysics · Physics 2015-06-11 D. Fabbian , F. Moreno-Insertis , E. Khomenko , Å. Nordlund
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