Astrophys. J., 864, 99-99 (2018/September-1)
Classically and asteroseismically constrained 1D stellar evolution models of α Centauri A and B using empirical mixing length calibrations.
JOYCE M. and CHABOYER B.
Abstract (from CDS):
The bright, nearby binary α Centauri provides an excellent laboratory for testing stellar evolution models, because it is one of the few stellar systems for which we have high-precision classical (mass, radius, luminosity) and asteroseismic (p-mode) observations. Stellar models are created and fit to the classical and seismic observations of both stars by allowing for the free variation of the convective mixing length parameter αMLT. This system is modeled using five different sets of assumptions about the physics governing the stellar models. There are 31 pairs of tracks (out of ∼150,000 generated) that fit the classical, binary, and seismic observational constraints of the system within 3σ. Models with each tested choice of input physics are found to be viable, but the optimal mixing lengths for α Cen A and α Cen B remain the same regardless of the physical prescription. The optimal mixing lengths are αMLT,A/α☉ = 0.932 and αMLT,B/α☉ = 1.095. That α Cen A and α Cen B require subsolar and supersolar mixing lengths, respectively, to fit the observations is a trend consistent with recent findings, such as those of Kervella et al., Joyce & Chaboyer, and Viani et al. The optimal models find an age for α Centauri of 5.3 ± 0.3 Gyr.
© 2018. The American Astronomical Society. All rights reserved.
asteroseismology - stars: evolution - stars: fundamental parameters - stars: interiors
View the reference in ADS
To bookmark this query, right click on this link: simbad:2018ApJ...864...99J and select 'bookmark this link' or equivalent in the popup menu