Dynamic Evolution of Emerging Magnetic Flux Tubes in the Solar Convective Envelope
Abstract
I present recent results on modeling the buoyant rise of active region scale flux tubes in the solar convective envelope based on both a thin flux tube model incorporating the effects of giant-cell convection as well as 3D spherical-shell anelastic MHD simulations. It is found that the dynamic evolution of the flux tube changes from magnetic buoyancy dominated to convection dominated as the initial field strength of the flux tube varies from about 100 kG to 15 kG. Overall, the effect of the convective flow is found to allow mid to weak field strength range flux tubes (∼ 15 kG - 50 kG) to develop emerging loops with properties that are more consistent with the observed properties of solar active regions. For these flux tubes, the convective flow is found to reduce the rise time, reduce the latitude of emergence through anchoring by downdrafts, and promote tilt angles that are consistent with the observed mean tilt of solar active regions because of the mean kinetic helicity in the flow. The initial twist of the tube cannot be too high in order for the tilt of the emerging loops to be dominated by the effect of the Coriolis force and be consistent with the mean tilt of solar active regions. I will also discuss the properties of the emerging flux tube as it approaches the top layers of solar convective envelope based on these models.
- Publication:
-
SDO-3: Solar Dynamics and Magnetism from the Interior to the Atmosphere
- Pub Date:
- October 2011
- Bibcode:
- 2011sdmi.confE..35F
- Keywords:
-
- SDO;
- SDO-3;
- SDO 3;
- SDO Workshop;
- LWS/SDO-3/SOHO-26/GONG-2011 Workshop;
- Solar Dynamic Observatory