Three Dimensional MHD Simulation of Solar Emerging Flux
and its Reconnection with Pre-Existing Coronal Field

H. Isobe (Kwasan Obs., Kyoto Univ.), T. Miyagosi, K. Shibata and T. Yokoyama

The magnetic field generated in the solar interior rises
due to the magnetic buoyancy instability and emerges
through the photosphere into the corona. In the presence
of pre-existing coronal field, magnetic reconnection can
occur and may causes various active phenomena such as X-ray
jets, surges and EUV explosive events.

Two dimensional MHD simulation of jet formation by magnetic
reconnection between emerging and coronal filed was carried
out by Yokoyama and Shibata (1995). However, observed jets
have sometimes helical structure, which indicates that
three dimensionality has significant role.

In this poster we present the result of three dimensional
Magnetohydrodymaic simulation of emerging flux and its
reconnection with pre-existing corona. First we present
3D version of Yokoyama and Shibata (1995)
and demonstrate the formation of 3D structure due to the
localized reconnection.
We also present a case of emerging twisted flux tube and
examine the formation of helical structure and generation
of torsional Alfven wave.