Addressing ambiguities in the evolutionary status of solar-mass stars

Abstract

Spectroscopic MK classifications have been obtained for a set of stars having abnormal indices on the Stromgren uvby photometric system. Two of these stars, HD 204848 and HD 207687, show extreme carbon anomalies. Moderately high-resolution spectroscopy (0.2 Angstrom) over the wavelength range of 3900 to 8800 Angstrom was compared with synthetic spectra for evolutionary models to give an indication of the true evolutionary status of these stars. The luminosities predicted from the modeling are found to be in agreement with HIPPARCOS observations.