Core Overshoot: An Improved Treatment and Constraints from Seismic Data

@article{Straka2005CoreOA,
  title={Core Overshoot: An Improved Treatment and Constraints from Seismic Data},
  author={Christian W. Straka and Pierre. Demarque and D. B. Guenther Institut fuer Theoretische Astrophysik and Universitaet Heidelberg and H Germany and Department of Physics Astronomy and Yale University and New Haven and Usa and Physics and Saint Mary's University and Halifax and Canada.},
  journal={The Astrophysical Journal},
  year={2005},
  volume={629},
  pages={1075-1090}
}
We present a comprehensive set of stellar evolution models for Procyon A in an effort to guide future measurements of both traditional stellar parameters and seismic frequencies toward constraining the amount of core overshoot in Procyon A and possibly other stars. Current observational measurements of Procyon A when combined with traditional stellar modeling only place a large upper limit on overshoot of αOV < 1.1. By carrying out a detailed pulsation analysis, we further demonstrate how p… Expand
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TLDR
It is found that g-modes are sensitive to model parameters that effect the structure of the core, such as convective core overshoot, the heavy-element abundance, and the evolutionary state (main sequence or shell hydrogen burning) of Procyon A. Expand
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We have calculated an array of stellar models for Procyon A that are based on the best physics available to us, including the latest opacities and nuclear cross sections. The array of models spansExpand
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The parallax and astrometric orbit of Procyon have been redetermined from PDS measurements of over 250 photographic plates spanning 83 years, with roughly 600 exposures used in the solution. TheseExpand
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In the course of a search for solar-like oscillations in bright late-type stars, Doppler variability was observed in the F5 subgiant Procyon. The variations have frequencies within a 1.1 mHz rangeExpand
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Theoretical isochrones have been constructed using the OPAL opacities specifically to study the color-magnitude diagram of the open star cluster NGC 2420. This cluster provides a rare test of coreExpand
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High-precision data on absolute dimensions of evolved eclipsing binaries have been used for a quantitative evaluation of the significance of convective overshoot in the stellar core. Eight detachedExpand
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The reexamination of astrophysical opacities has eliminated gross discrepancies between a variety of observations and theoretical calculations; thus allowing for more detailed tests of stellarExpand
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