THE PHYSICAL BASIS OF THE SPECTRAL CLASSIFICATION OF A, F AND G STARS

摘要

We present the first results of a precise scheme for spectral classification for the late B, A, F and early G-type stars. We have used ～15000 well classified stars from (Hauck & Mermilliod 1998) and with the Stromgren (b-y), [c_1] and [m_1] indices (Stromgren 1951) to define the regions in the [m_1]-[c_1] diagram. We also generate calibrations for the effective temperature (T_(eff)) and the surface gravity.