AXIAL ROTATION - STATISTICS OF EARLY B-STARS AND EFFECT ON LINE-INTENSITIES

Frequency distributions of v sin i on a uniform system are presented for O5-B5 stars. Theoretical distributions are given which take into account the effect of observational errors. Some physical implications are discussed. It is found that B stars probably do not rotate as solid bodies. Difficulties are encountered if Be stars are postulated to be rotating near their break-up velocity unless most of them are evolved from the main sequence, or have large differential rotations. A distinct correlation between hydrogen line strength and axial rotation is found. © Royal Astronomical Society.