157 citations · 1.1k across the 23 of their papers we have counts for
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Ejections of magnetic structures above a spherical wedge driven by a convective dynamo with differential rotation
Jörn Warnecke, Petri J. Käpylä, Maarit. J. Mantere +1
We combine a convectively driven dynamo in a spherical shell with a nearly isothermal density-stratified cooling layer that mimics some aspects of a stellar corona to study the eme…
Dependence of the large-scale vortex instability on latitude, stratification and domain size
Maarit J. Mantere, Petri J. Käpylä, Thomas Hackman
In an earlier study, we reported on the excitation of large-scale vortices in Cartesian hydrodynamical convection models subject to rapid enough rotation. In that study, the condit…
Multiperiodicity, modulations and flip-flops in variable star light curves I. Carrier fit method
J. Pelt, N. Olspert, M. J. Mantere +1
The light curves of variable stars are commonly described using simple trigonometric models, that make use of the assumption that the model parameters are constant in time. This as…
Effects of stratification in spherical shell convection
P. J. Käpylä, M. J. Mantere, A. Brandenburg
We report on simulations of mildly turbulent convection in spherical wedge geometry with varying density stratification. We vary the density contrast within the convection zone by…
Doppler images of II Pegasi for 2004-2010
Thomas Hackman, Maarit J. Mantere, Marjaana Lindborg +4
Aims. We study the spot activity of II Peg during the years 2004-2010 to determine long- and short-term changes in the magnetic activity. In a previous study, we detected a persist…
Starspots due to large-scale vortices in rotating turbulent convection
P. J. Käpylä, M. J. Mantere, T. Hackman
We study the generation of large-scale vortices in rotating turbulent convection by means of Cartesian direct numerical simulations. We find that for sufficiently rapid rotation, c…