Tests of evolutionary sequences using color-magnitude diagrams of globular clusters.

Theoretical models of stellar evolution are examined critically with regard to the accuracy of the physics on which they are based and the adequacy of their canonical assumptions (generally involving the negligibility of certain phenomena). Observational data on globular-cluster populations are used in detailed comparisons of model-predicted temperature, luminosity, and duration with observed colors, magnitudes, and star counts, respectively. Particular attention is given to the lower main sequence, the upper main sequence and turnoff (mixing-length calibration, turnoff temperatures and luminosities, and blue stragglers), the subgiant and red-giant branches (luminosity function, luminosities and core masses, and the He flash), and core and shell He burning on the horizontal and asymptotic-giant branches. Diagrams and graphs are provided, and results for a complete sample of the M3 cluster are presented in a table and briefly characterized.