HEATING OF CORONAL LOOP FOOTPOINTS BY SLINGSHOT MAGNETIC RECONNECTION DURING TWO LOOP INTERACTIONS DRIVEN BY A MOVING SOLITARY MAGNETIC KINK

摘要

Recent Transition Region and Coronal Explorer observations of active loops in the EUV showed that there is a class of EUV loops that consists of near-isothermal loop threads with substantially smaller temperature gradients than are predicted by the uniform loop heating model. These results support coronal heating mechanisms operating in or near the chromosphere and transition region. We propose a new local heating model of loop footpoints in the chromosphere in which there occurs nonuniform heating by slingshot magnetic reconnection during two loops' interaction, driven by the moving solitary magnetic kink, which was recently found by three-dimensional MHD simulation and is characterized as a moving solitary magnetic flux ring with a pair of counterrotating vortex rings. We also show that the loop interaction results in the formation of helical up- and downflows driven by the slingshot magnetic reconnection.