THE CALIBRATION OF UVBY-BETA-PHOTOMETRY FOR B-STAR, A-STAR AND F-STAR

We present an investigation into the determination of fundamental valu es of T-eff and log g. A re-evaluation of the fundamental values of T- eff determined by Code et al. (1976) using modern flux measurements is presented, but there are no significant changes. A determination of f undamental values of T-eff for four binary systems with fundamental lo g g values has been performed. Medium-resolution H beta profiles of th e fundamental stars have been obtained and compared to theoretical pro files in order to provide estimates of the parameters that have not be en obtained in a fundamental manner. We have calculated a table of syn thetic beta indices which explicitly include the effects of metal-line blocking. We find that these beta indices are in good agreement with the photometric values. A comparison of theoretical uvby colours is al so presented, and found to be in very good agreement with the photomet ric colours.