1111.2461 (Emre Işık)
Emre Işık
We present results from a model for magnetic flux generation and transport in
cool stars and a qualitative comparison of models with observations. The method
combines an alpha-omega dynamo at the base of the convection zone, buoyant rise
of magnetic flux tubes, and a surface flux transport model. Based on a
reference model for the Sun, numerical simulations were carried out for model
convection zones of G- and K-type main sequence and subgiant stars. We
investigate magnetic cycle properties for stars with different rotation
periods, convection zone depths, and dynamo strengths. For a Sun-like star with
P_rot=9 d, we find that a cyclic dynamo can underly an apparently non-cyclic,
'flat' surface activity, as observed in some stars. For a subgiant K1 star with
P_rot=2.8 d the long-term activity variations resemble the multi-periodic
cycles observed in V711 Tau, owing to high-latitude flux emergence, weak
transport effects and stochastic processes of flux emergence.
View original:
http://arxiv.org/abs/1111.2461
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