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Related papers: Solar abundance problem

200 papers

What might be the most appropriate set of interstellar reference abundances of chemical elements (both in gas and in dust) relative to hydrogen has been a subject of much discussion in the past decade. While historically the Sun has been…

Astrophysics · Physics 2009-11-10 Aigen Li

This review highlights current (and future) hot topics in astrophysics where atomic or molecular input data are (or will be) essential, with special emphasis on topics relating to nucleosynthesis and cosmochemistry. We first discuss issues…

Astrophysics · Physics 2009-11-10 A. Jorissen

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

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

Determining the He/H ratio in cool stars presents a fundamental astrophysical challenge. While this ratio is established for hot O and B stars, its extrapolation to cool stars remains uncertain due to the absence of helium lines in their…

Solar and Stellar Astrophysics · Physics 2024-10-29 Satyajeet Moharana , B. P. Hema , Gajendra Pandey

Hydrostatic equilibrium and energy conservation determine the conditions in the gravitationally stabilized solar fusion reactor. We assume a matter density distribution varying non- linearly through the central region of the Sun. The…

Astrophysics · Physics 2011-03-17 H. J. Haubold , A. M. Mathai

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

We derive the abundance of 19 elements in a sample of 64 stars with fundamental parameters very similar to solar, which minimizes the impact of systematic errors in our spectroscopic 1D-LTE differential analysis, using high-resolution…

Solar and Stellar Astrophysics · Physics 2009-12-10 I. Ramirez , J. Melendez , M. Asplund

Recent 3D-simulations have shown that the turbulent kinetic flux (TKF) is significant. We discuss the effects of TKF on the size of convection zone and find that the TKF may help to solve the solar abundance problem. The solar abundance…

Solar and Stellar Astrophysics · Physics 2015-06-19 Q. S. Zhang

The interface between the bright solar surface and the million-degree corona continues to hold the key to many unsolved problems in solar physics. Advances in instrumentation now allow us to observe the dynamic structures of the solar…

Solar and Stellar Astrophysics · Physics 2019-02-13 Tiago M. D. Pereira

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

The measurement of stellar properties such as chemical compositions, masses and ages, through stellar spectra, is a fundamental problem in astrophysics. Progress in the understanding, calculation and measurement of atomic properties and…

Solar and Stellar Astrophysics · Physics 2016-06-08 Paul S. Barklem

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

To understand the chemical evolution of the Galaxy, we need to understand the contribution of PNe in the 3He abundance. 3He abundances have been detected only in a couple of PNe, their abundances are consistent with the standard models, in…

Astrophysics of Galaxies · Physics 2015-06-15 L. Guzman-Ramirez , J. E. Pineda , A. A. Zijlstra , R. Stancliffe , A. Karakas

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 sun's role in the earth's recent warming remains controversial even though there is a good deal of evidence to support the thesis that solar variations are a very significant factor in driving climate change both currently and in the…

General Physics · Physics 2010-07-29 Gerald E. Marsh

Aims. A sample of early B-type stars in OB associations and the field within the solar neighbourhood is studied comprehensively. Present-day abundances for the astrophysically most interesting chemical elements are derived. Methods.…

Solar and Stellar Astrophysics · Physics 2012-03-29 Maria-Fernanda Nieva , Norbert Przybilla

We estimate the main-sequence age and heavy-element abundance of the Sun by means of an asteroseismic calibration of theoretical solar models using only low-degree acoustic modes from the BiSON. The method can therefore be applied also to…

Solar and Stellar Astrophysics · Physics 2015-05-30 G. Houdek , D. O. Gough

The standard solar model was so reliable that it could predict the existence of the massive neutrino. Helioseismology measurements were so precise that they could determine the depth of the convection zone. This agreement between theory and…

Astrophysics · Physics 2009-11-13 J. T. Schmelz , K. Nasraoui , J. K. Roames , L. A. Lippner , J. W. Garst

We review three Li problems. First, the Li problem in the Sun, for which some previous studies have argued that it may be Li-poor compared to other Suns. Second, we discuss the Li problem in planet hosting stars, which are claimed to be…

Solar and Stellar Astrophysics · Physics 2010-11-22 J. Melendez , I. Ramirez , L. Casagrande , M. Asplund , B. Gustafsson , D. Yong , J. D. do Nascimento , M. Castro , M. Bazot