QUANTITATIVE SPECTRAL TYPES FOR 19 ALGOL SECONDARIES

Time-resolved spectra of 19 short-period Algol-type binary star system s obtained during total eclipse are used to derive the temperature spe ctral class of the mass-losing secondary component. The spectral class ifications employed a quantitative comparison of the strengths of abso rption features in stars of known spectral class with those of the pro gram stars. The luminosity spectral class cannot be determined from th ese data, so both main-sequence and giant stars were used for the comp arison. Our spectral types are compared with published types and found to be generally in good agreement, unless the published types are der ived from the light curves. The photometrically determined types are s ystematically later than our directly determined types. This effect is shown also to exist in catalogs of Algol parameters.