Effects of rotation on colours and line indices of stars. III - Binary and peculiar stars

Abstract

The broad-band UBV colors and the intermediate band uvby colors of Alpha Persei, Pleiades, and the Scorpio-Centaurus association are analyzed for rotation effects. An attempt was made to discriminate normal single stars from that of binary and peculiar stars after taking the observed rotation effects into account. It is found that the spread in the observed colors does not in general allow such a discrimination, except that the objects with large reddening are double-lined binaries, peculiar stars or emission-lined objects. The few normal stars in these three clusters with such large reddening are listed as they are likely to belong to one of the above classes.