Observational features sensitive to convective core overshooting in the colour

Abstract

The colour-magnitude diagrams (CMDs) of star clusters are valuable tool for the study of stellar evolution. The CMDs of star clusters of our galaxy as well as of the Magellanic Clouds obtained using CCD broad band photometry have therefore been compared with the latest theoretical stellar evolutionary models and features sensitive to the convective core overshooting have been identified in the CMDs of the star clusters. The main-sequence turn-off mass in such clusters lies in the range of 1.3 to 10 solar mass. Dependence of age of star cluster and of the integrated luminosity function of main-sequence stars normalised to the number of evolved stars on the extent of core overshooting mixing has been studied in detail. For this, synthetic CMDS produced using recent stellar evolutionary models and considering the effect of binarity and observational errors have been compared with observed ones. Stellar models with convective core overshooting make the cluster older.