Early solar mass loss, opacity uncertainties, and the solar abundance problem

Conference · Thu Jan 01 04:00:00 EST 2009

DOI:https://doi.org/10.1063/1.3246566· OSTI ID:991271

Guzik, Joyce Ann ^[1]; Keady, John ^[1]; Kilcrease, David ^[1]

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1. Los Alamos National Laboratory

Solar models calibrated with the new element abundance mixture of Asplund et al. published in 2005 no longer produce good agreement with the sound speed, convection zone depth, and convection zone helium abundance inferred from solar oscillation data. Attempts to modify the input physics of the standard model, for example, by including enhanced diffusion, increased opacities, accretion, convective overshoot, or gravity waves have not restored the good agreement attained with the prior abundances. Here we present new models including early mass loss via a stronger solar wind. Early mass loss has been investigated prior to the solar abundance problem to deplete lithium and resolve the 'faint early sun problem'. We find that mass loss modifies the core structure and deepens the convection zone, and so improves agreement with oscillation data using the new abundances: however the amount of mass loss must be small to avoid destroying all of the surface lithium, and agreement is not fully restored. We also considered the prospects for increasing solar interior opacities. In order to increase mixture opacities by the 30% required to mitigate the abundance problem, the opacities of individual elements (e.g., O, N, C, and Fe) must be revised by a factor of two to three for solar interior conditions: we are investigating the possibility of broader calculated line wings for bound-bound transitions at the relevant temperatures to enhance opacity. We find that including all of the elements in the AGS05 opacity mixture (through uranium at atomic number Z=92) instead of only the 17 elements in the OPAL opacity mixture increases opacities by a negligible 0.2%.

• Research Organization: Los Alamos National Laboratory (LANL)
• Sponsoring Organization: DOE
• DOE Contract Number: AC52-06NA25396
• OSTI ID: 991271
• Report Number(s): LA-UR-09-04891; LA-UR-09-4891
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABUNDANCE
ATOMIC NUMBER
CONVECTION
DIFFUSION
ELEMENT ABUNDANCE
GRAVITY WAVES
HELIUM
LITHIUM
MIXTURES
OPACITY
OPALS
OSCILLATIONS
PHYSICS
SOLAR WIND
STANDARD MODEL
STAR MODELS
SUN
URANIUM
VELOCITY