Interior models for Procyon A: Evolutionary status and oscillation properties

  • P. Demarque
  • D. B. Guenther
Session II: Dynamos and Stellar Activity: Theory
Part of the Lecture Notes in Physics book series (LNP, volume 254)


Evolutionary sequences have been constructed to determine the evolutionary status of Procyon A. We find that Procyon could be in any of the following three evolutionary phases: (a) core hydrogen burning; (b) core exhaustion; (c) hydrogen burning shell narrowing. However, both timescale and luminosity arguments strongly favor possibility (a).

The models also indicate that convective overshoot takes place at the edge of the convective core, as inferred for stars of this mass from observations of color-magnitude diagrams of star clusters. There is a very thin convective zone near the surface. Earlier suggestions that the astrometric mass of Procyon A is over-estimated by about 15 percent are confirmed.

The asymptotic half-spacing of the p-modes for low degree and large radial order is found to be between 25 and 30 microHerz.


Star Cluster Stellar Model Hydrogen Burning Evolutionary Track Convective Core 
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Copyright information

© Springer-Verlag 1986

Authors and Affiliations

  • P. Demarque
    • 1
  • D. B. Guenther
    • 1
  1. 1.Center for Solar and Space ResearchYale UniversityNew HavenUSA

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