Global-scale Magnetism (and Cycles) in Dynamo Simulations of Stellar Convection Zones
Brown, Benjamin P.
Browning, Matthew K.
Brun, Allan Sacha
Miesch, Mark S.
Astronomical Society of the Pacific Conference Series
Astronomical Society of the Pacific
© in final form by Astronomical Society of the Pacific
Young solar-type stars rotate rapidly and are very magnetically active. The magnetic fields at their surfaces likely originate in their convective envelopes where convection and rotation can drive strong dynamo action. Here we explore simulations of global-scale stellar convection in rapidly rotating suns using the 3-D MHD anelastic spherical harmonic (ASH) code. The magnetic fields built in these dynamos are organized on global-scales into wreath-like structures that span the convection zone. We explore one case rotates five times faster than the Sun in detail. This dynamo simulation, called case D5, has repeated quasi-cyclic reversals of global-scale polarity. We compare this case D5 to the broader family of simulations we have been able to explore and discuss how future simulations and observations can advance our understanding of stellar dynamos and magnetism.
NASA through Heliophysics Theory Program grants
NSF Astronomy and Astrophysics postdoctoral fellowship
NASA SR&T grant
Programme National Soleil-Terre of CNRS/INSU (France)
STARS2 grant from the European Research Council
8 pages, 3 figures; to appear in proceedings of Cool Stars 16, Seattle Aug 29 - Sep 2, 2010
Astronomical Society of the Pacific Conference Series, 2012, 448, 277