Studies of Stellar Rotation.IV. a Comparison of Rotational Velocities in the Alpha Persei Cluster and the Pleiades

Abstract

The rotational velocities of nearly all stars in the a Per cluster brighter than M v = +3 5 have been determined The function (V sin i) is shown to be larger than that for the field stars. It agrees well with (V sin ¿) for the Pleiades, thereby supporting Eggen's suggestion that the two clusters have a common origin. The frequency distribution / of rotational velocities is derived and is found to be fairly well represented by a Maxwellian distribution The difference between / in a Per and the Pleiades and / in the field for stars in the range-0 05