Reconciling solar and stellar magnetic cycles with nonlinear dynamo simulations

Research paper by A. Strugarek, P. Beaudoin, P. Charbonneau, A. S. Brun, J. -D. do Nascimento

Indexed on: 13 Jul '17Published on: 13 Jul '17Published in: arXiv - Astrophysics - Solar and Stellar Astrophysics


The magnetic fields of solar-type stars are observed to cycle over decadal periods -11 years in the case of the Sun. The fields originate in the turbulent convective layers of stars and have a complex dependency upon stellar rotation rate. We have performed a set of turbulent global simulations that exhibit magnetic cycles varying systematically with stellar rotation and luminosity. We find that the magnetic cycle period is inversely proportional to the Rossby number, which quantifies the influence of rotation on turbulent convection. The trend relies on a fundamentally non-linear dynamo process and is compatible with the Sun's cycle and those of other solar-type stars.