Models of extended decretion disks of critically rotating stars

Petr Kurfürst, Achim Feldmeier, Jiří Krtička

Published 2013-09-13Version 1

Massive stars may during their evolution reach the phase of critical rotation when the further increase in rotational speed is no longer possible. The ejection of matter in the equatorial region forms the gaseous outflowing disk, which allows the star to remove the excess of its angular momentum. The outer part of the disk can extend up to large distance from the parent star. We study the evolution of density, radial and azimuthal velocity and angular momentum loss rate of equatorial decretion disk up to quite distant outer regions. We calculate the evolution of density, radial and azimuthal velocity from the initial Keplerian state until the disk approaches the final stationary state.