Statistical Analysis of Reconnection Inflows in Solar Flares

Narukage N. and Shibata K. (Kyoto Univ.)

Solar flare is an explosion on the solar surface and releases huge energy
in a short time. It is widely believed that the energy is stored in
magnetic field and the flare is caused by magnetic reconnection. The
reconnection model has been established at least phenomenologically by
Yohkoh. However, the inflow, which is predicted by the reconnection theory,
has not been discovered, and it remains mystery. In 2000, Yokoyama et al.
discovered such reconnection inflow in a solar flare observed with SOHO/EIT,
but no other observation of reconnection inflow has been reported until now.
The generality of inflow remains doubtful. We surveyed the reconnection
inflow in the full Sun movies taken with SOHO/EIT and discovered 13 inflows.
We measured the line-of-sight velocity of the inflows using SOHO/EIT images,
the angle between magnetic neutral line and line-of-sight direction in the
inflows using SOHO/MDI images, and the energy release rate of the flares
associated with the inflows using Yohkoh/SXT images. Based on this results,
we estimated some physical quantities of the inflows, e.g. the real inflow
velocity and reconnection rate. This result is conclusive evidence of
reconnection and the clue to the solution of flare mechanism.