MHD simulation of emerging flux tube in the sun
- Initial State of Simulation

- Evolution of emerging magnetic field

- Comparison to Potential Field

- Current Density Distribution at the Lower Atmosphere
(Color lines show field lines.)

- Sigmoid on the Sun
(Top: Sigmoid observed on the sun.
Bottom: Sigmoidal structure reproduced in numerical simulation.
Brightness of field lines reflects the current density distributed at
the footpoint of individual field lines.)
