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Related papers: Element Diffusion in the Solar Interior

200 papers

Thermohaline convection is a standard chemical mixing process in stellar interiors, yet its mixing efficiency is not fully settled. Competing theories predict turbulent diffusion coefficients, $D_\mu$, that can differ by orders of…

Solar and Stellar Astrophysics · Physics 2026-05-06 Valentin A. Skoutnev

The element settling due to the combined effects of gravity, thermal gradient, radiative acceleration and concentration gradient may lead to important abundance variations inside the stars, which cannot be neglected in the computations of…

Astrophysics · Physics 2007-05-23 Sylvie Vauclair

Aims. Atomic diffusion, including the effect of radiative accelerations on individual elements, leads to important variations of the chemical composition inside the stars. The accumulation in specific layers of the elements, which are the…

Solar and Stellar Astrophysics · Physics 2016-04-27 M. Deal , O. Richard , S. Vauclair

On the basis of local nonequilibrium approach, the one-dimensional model of the solute diffusion during rapid solidification of the binary alloy in the semi-infinite volume is considered. Within the scope of the model it is supposed that…

Materials Science · Physics 2009-12-23 G. L. Buchbinder , P. Martaller

The Sun is moving through a warm ($\sim$6500 K) and partly ionized local interstellar cloud (LIC) with a velocity of $\sim$26 km/s. Recent measurements of the ionization of the LIC (Wolff et al., 1999) suggest that interstellar helium in…

Astrophysics · Physics 2009-11-10 Vlad Izmodenov , Yury G. Malama , George Gloeckler , Johannes Geiss

We calculate accurate solar models and report the detailed time dependences of important solar quantities. We use helioseismology to constrain the luminosity evolution of the sun and report the discovery of semi-convection in evolved solar…

Astrophysics · Physics 2008-11-26 John N. Bahcall , M. H. Pinsonneault , Sarbani Basu

On its journey through the Galaxy, the Sun passes through diverse regions of the interstellar medium. High-resolution spectroscopic measurements of interstellar absorption lines in spectra of nearby stars show absorption components from…

We produce YbF molecules with a density of 10^18 m^-3 using laser ablation inside a cryogenically-cooled cell filled with a helium buffer gas. Using absorption imaging and absorption spectroscopy we study the formation, diffusion,…

Two main models have been developed to explain the mechanisms of release, heating and acceleration of the nascent solar wind, the wave-turbulence-driven (WTD) models and reconnection-loop-opening (RLO) models, in which the plasma release…

Solar and Stellar Astrophysics · Physics 2018-05-23 Hui Fu , Maria S. Madjarska , Bo Li , LiDong Xia , ZhengHua Huang

Primary inversions of solar oscillation frequencies coupled with the equations of thermal equilibrium and other input physics, enable us to infer the temperature and hydrogen abundance profiles inside the Sun. These profiles also help in…

Astrophysics · Physics 2008-11-26 H. M. Antia , S. M. Chitre

In spite of the great effort made in the last decades to improve our understanding of stellar evolution, significant uncertainties remain due to our poor knowledge of some complex physical processes that require an empirical calibration,…

Solar and Stellar Astrophysics · Physics 2015-06-22 Alessandro Bressan , Leo Girardi , Paola Marigo , Philip Rosenfield , Jing Tang

Each time diffusion of elements is invoked in explaining abundance anomalies in a star, this supposes implicitly that a stratification process is in progress somewhere in that star. This means also, that the element abundances can still be…

Astrophysics · Physics 2007-05-23 Georges Alecian

The primordial elements, H, He and Li are included in a low temperature equation of state and monochromatic opacity function. The equation of state and opacity function are incorporated into the stellar evolution code NG-ELMS, which makes…

Astrophysics · Physics 2008-11-26 G. J. Harris , A. E. Lynas-Gray , S. Miller , J. Tennyson

It is generally argued that most clusters of galaxies host cooling flows in which radiative cooling in the centre causes a slow inflow. However, recent observations by Chandra and XMM conflict with the predicted cooling flow rates. Amongst…

Astrophysics · Physics 2009-11-07 M. Bruggen

We investigate the evaporation of trace amounts of helium solvated in liquid water using molecular dynamics simulations and theory. Consistent with experimental observations, we find a super-Maxwellian distribution of kinetic energies of…

Chemical Physics · Physics 2024-08-21 Kritanjan Polley , Kevin R. Wilson , David T. Limmer

The IBEX-Lo instrument on the Interstellar Boundary Explorer (IBEX) mission observes primary and secondary interstellar helium in its 4 lowest energy steps. Observations of these helium populations have been systematically analyzed and…

Solar and Stellar Astrophysics · Physics 2024-09-19 H. Islam , N. Schwadron , E. Moebius , F. Rahmanifard , J. M. Sokol , A. Galli , D. J. McComas , P. Wurz , S. A. Fuselier , K. Fairchild , D. Heirtzler

Helioseismology has revealed the internal density and rotation profiles of the Sun. Yet, knowledge of its magnetic fields and meridional circulation is confined much closer to the surface, and latitudinal entropy gradients are below…

Solar and Stellar Astrophysics · Physics 2019-01-29 Lee Gunderson , Amitava Bhattacharjee

We present some analytical solutions to the Einstein equations, describing radiating collapsing spheres in the diffusion approximation. Solutions allow for modeling physical reasonable situations. The temperature is calculated for each…

General Relativity and Quantum Cosmology · Physics 2008-11-26 L. Herrera , A. Di Prisco , J. Ospino

Spectra of late-type stars are usually analyzed with static model atmospheres in local thermodynamic equilibrium (LTE) and a homogeneous plane-parallel or spherically symmetric geometry. The energy balance requires particular attention, as…

Astrophysics · Physics 2009-11-06 Carlos Allende Prieto , Paul S. Barklem , Martin Asplund , Basilio Ruiz Cobo

While conventional interior models for Jupiter and Saturn are based on the simplistic assumption of a solid core surrounded by a homogeneous gaseous envelope, we derive new models with an inhomogeneous distribution of heavy elements, i.e. a…

Earth and Planetary Astrophysics · Physics 2015-06-03 Jérémy Leconte , Gilles Chabrier
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