We attempt to model magnetic reconnection during the two-ribbon flare in a gravitationally stratified solar atmosphere with the Lundquist number of S=10~6 using 2 D simulations.We found that the tearing mode instabili...We attempt to model magnetic reconnection during the two-ribbon flare in a gravitationally stratified solar atmosphere with the Lundquist number of S=10~6 using 2 D simulations.We found that the tearing mode instability leads to inhomogeneous turbulence inside the reconnecting current sheet(CS)and invokes the fast phase of reconnection.Fast reconnection brings an extra dissipation of magnetic field which enhances the reconnection rate in an apparent way.The energy spectrum in the CS shows a power law pattern and the dynamics of plasmoids govern the associated spectral index.We noticed that the energy dissipation occurs at a scale l_(ko)of 100-200 km,and the associated CS thickness ranges from 1500 to 2500 km,which follows the Taylor scale l_(T)=l_(ko)S_(1/6).The termination shock(TS)appears in the turbulent region above flare loops,which is an important contributor to heating flare loops.Substantial magnetic energy is converted into both kinetic and thermal energies via TS,and the cumulative heating rate is greater than the rate of the kinetic energy transfer.In addition,the turbulence is somehow amplified by TS,in which the amplitude is related to the local geometry of the TS.展开更多
基金the Strategic Priority Research Programme of Chinese Academy of Sciences(CAS)with grants XDA17040507 and QYZDJ-SSWSLH012the National Natural Science Foundation of China(NSFC,Grant Nos.12073073,1193300911973083 and U2031141)+2 种基金grants associated with the Yunling Scholar Project of Yunnan Provincethe Yunnan Province Scientist Workshop of Solar Physicsgrants 202101AT070018 and 2019FB005 associated with the Applied Basic Research of Yunnan Province。
文摘We attempt to model magnetic reconnection during the two-ribbon flare in a gravitationally stratified solar atmosphere with the Lundquist number of S=10~6 using 2 D simulations.We found that the tearing mode instability leads to inhomogeneous turbulence inside the reconnecting current sheet(CS)and invokes the fast phase of reconnection.Fast reconnection brings an extra dissipation of magnetic field which enhances the reconnection rate in an apparent way.The energy spectrum in the CS shows a power law pattern and the dynamics of plasmoids govern the associated spectral index.We noticed that the energy dissipation occurs at a scale l_(ko)of 100-200 km,and the associated CS thickness ranges from 1500 to 2500 km,which follows the Taylor scale l_(T)=l_(ko)S_(1/6).The termination shock(TS)appears in the turbulent region above flare loops,which is an important contributor to heating flare loops.Substantial magnetic energy is converted into both kinetic and thermal energies via TS,and the cumulative heating rate is greater than the rate of the kinetic energy transfer.In addition,the turbulence is somehow amplified by TS,in which the amplitude is related to the local geometry of the TS.
