The rotation periods of cool stars: Measurements, uses, connections and prospects
23rd - 26th September 2019
Talk
Antisolar differential rotation of slowly rotating cool stars
Günther Rüdiger, AIP
Rotating stellar convection transports angular momentum equatorward generating the characteristic equatorial acceleration of the solar rotation. New numerical box simulations, however, provide a poleward angular momentum transport for slow rotation and an equatorward transport for fast rotation. The explanation is that for slow rotation always a negative radial gradient of the angular velocity appears which in combination with a so far neglected rotation-induced off-diagonal eddy viscosity term provides antisolar rotation laws with decelerated equator. In consequence, the observation of the differential rotation of slowly rotating stars will thus lead to a better understanding of the actual stress-strain relation and the underlying rotating turbulence.