Abstract:
Using multiwavelength imaging observations from the Atmospheric Imaging Assembly on board the
Solar
Dynamics Observatory
on 2012 May 3, we present a novel physical scenario for the formation of a temporary
X-point in the solar corona, where plasma dynamics are forced externally by a moving prominence. Natural
diffusion was not predominant; however, a prominence driven in
fl
ow occurred
fi
rst, forming a thin current sheet,
thereafter enabling a forced magnetic reconnection at a considerably high rate. Observations in relation to the
numerical model reveal that forced reconnection may rapidly and ef
fi
ciently occur at higher rates in the solar
corona. This physical process may also heat the corona locally even without establishing a signi
fi
cant and self-
consistent diffusion region. Using a parametric numerical study, we demonstrate that the implementation of the
external driver increases the rate of the reconnection even when the resistivity required for creating normal
diffusion region decreases at the X-point. We conjecture that the appropriate external forcing can bring the
oppositely directed
fi
eld lines into the temporarily created diffusion region
fi
rst via the plasma in
fl
ows as seen in
the observations. The reconnection and related plasma out
fl
ows may occur thereafter at considerably larger rates.
