9 citations · 9 across the 1 of their papers we have counts for
5 papers
Shapes of stellar activity cycles
T. Willamo, T. Hackman, J. J. Lehtinen +4
Magnetic activity cycles are an important phenomenon in both the Sun and other stars. The shape of the solar cycle is commonly characterised by a fast rise and a slower decline, bu…
Differences in the solar cycle variability of simple and complex active regions during 1996-2018
Shabnam Nikbakhsh, Eija Tanskanen, Maarit Käpylä +1
Aims. Our aim is to examine the solar cycle variability of magnetically simple and complex active region. Methods. We studied simple ( and ) and complex ( and ) acti…
Stellar dynamos in the transition regime: multiple dynamo modes and anti-solar differential rotation
M. Viviani, M. J. Käpylä, J. Warnecke +2
Global and semi-global convective dynamo simulations of solar-like stars are known to show a transition from an anti-solar (fast poles, slow equator) to solar-like (fast equator, s…
Starspot activity of HD 199178. Doppler images from 1994--2017
Thomas Hackman, Iya Ilyin, Jyri J. Lehtinen +4
Context. Studying the spots of late-type stars is crucial for distinguishing between the various proposed dynamo mechanisms believed to be the main cause of starspot activity. For…
Long-term variations of turbulent transport coefficients in a solar-like convective dynamo simulation
Frederick A. Gent, Maarit J. Käpylä, Jörn Warnecke
The Sun, aside from its eleven year sunspot cycle is additionally subject to long term variation in its activity. In this work we analyse a solar-like convective dynamo simulation,…