Observational Tests and Predictive Stellar Evolution

Observational Tests and Predictive Stellar Evolution II: Non-standard Models

We examine contributions of second order physical processes to the results of stellar evolution calculations which are amenable to direct observational testing. In the first paper in the series (Young, Mamajek, Arnett, & Liebert 2001) we established baseline results using only physics which are common to modern stellar evolution codes. In the current paper we establish how much of the discrepan...

0 v 1 2 3 M ar 2 00 1 Observational Tests and Predictive Stellar Evolution

We compare eighteen binary systems with precisely determined radii and masses from 23 to 1.1 M⊙, and stellar evolution models produced with our newly revised code TYCHO. “Overshooting” and rotational mixing were suppressed in order to establish a baseline for isolating these and other hydrodynamic effects. Acceptable coeval fits are found for sixteen pairs without optimizing for heavy element o...

Critical tests of stellar evolution in open clusters II . Membership , duplicity , and stellar and dynamical evolution in NGC 3680 ? , ? ?

Based on new, accurate photometry, radial velocities, and proper motions for the intermediate-age open cluster NGC 3680, we identify individual single and binary cluster members and field stars in the colour-magnitude diagram (CMD). This basic step turns out to be crucial for a proper understanding of the cluster CMD: ∼60% of the stars are found to be field stars, and over 50% of the cluster st...

Observational tests of the evolution of spheroidal galaxies

Granato et al. (2004a) have elaborated a physically grounded model exploiting the mutual feedback between star-forming spheroidal galaxies and the active nuclei growing in their cores to overcome, in the framework of the hierarchical clustering scenario for galaxy formation, one of the main challenges facing such scenario, i.e. the fact that massive spheroidal galaxies appear to have formed muc...

Stellar Structure and Evolution