Retardation of angular velocity of a rotating star due to mass loss

Variations of angular velocity of a rotating star on the upper main sequence due to mass loss driven by various mechanisms, like radiation, corpuscule ejection, and stellar wind, are examined. Expressions for the variations of angular velocity are derived by considering a model of a rotating star. The theoretical results show that the angular velocity decreaseswith time due tomass loss. The obtained results are applied to a hot fast-rotating star V1182 Aql (O9 V) and to Y Cyg (B0 V).