Rotational velocities of A-type stars - IV. Evolution of rotational velocities

  title={Rotational velocities of A-type stars - IV. Evolution of rotational velocities},
  author={Jean Zorec and Fr{\'e}d{\'e}ric Royer},
  journal={Astronomy and Astrophysics},
Context. In previous works of this series, we have shown that late B- and early A-type stars have genuine bimodal distributions of rotational velocities and that late A-type stars lack slow rotators. The distributions of the surface angular velocity ratio Ω/Ω crit (Ω crit is the critical angular velocity) have peculiar shapes according to spectral type groups, which can be caused by evolutionary properties. Aims. We aim to review the properties of these rotational velocity distributions in some… 
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