Electron acceleration in interaction of magnetic islands in large temporal-spatial turbulent magnetic reconnection  

作　　者：BoJing Zhu Hui Yan David A Yuen YaoLin Shi 

机构地区：[1]Yunnan Observatories, Chinese Academy of Sciences [2]Center for Astronomical Mega-Science, Chinese Academy of Sciences [3]National Supercomputer Center in Guangzhou, Sun Yat-sen University [4]Department of Earth Science and Minnesota Supercomputing Institute, University of Minnesota [5]Applied Physics and Applied Mathematics Department, Columbia University [6]Key Laboratory of Computing Geodynamics, Chinese Academy of Sciences [7]College of Earth and Planetary Sciences, University of Chinese Academy of Sciences

出　　处：《Earth and Planetary Physics》2019年第1期17-25,共9页地球与行星物理（英文版）

基　　金：supported by the strategic priority research program of CAS (XDA17040507, XDA15010900);the national basic research program of China (2013CBA01503);the key program of NSFC (11333007);joint funds of NSFC(U1631130);frontier science key programs of CAS (QYZDJ-SSWSLH012);the program for innovation team of Yunnan Province;the program for Guangdong introducing Innovative and entrepreneurial teams (2016ZT06D211);the special program for applied research on super computation of the NSFC-Guangdong joint fund (second phase) under No.U1501501

摘　　要：A new combined Fermi, betatron, and turbulent electron acceleration mechanism is proposed in interaction of magnetic islands during turbulent magnetic reconnection evolution in explosive astrophysical phenomena at large temporal-spatial scale(LTSTMR), the ratio of observed current sheets thickness to electron characteristic length, electron Larmor radius for low-β and electron inertial length for high-β, is on the order of 10^(10)–10^(11); the ratio of observed evolution time to electron gyroperiod is on the order of 10~7–10~9).The original combined acceleration model is known to be one of greatest importance in the interaction of magnetic islands; it assumes that the continuous kinetic-dynamic temporal-spatial scale evolution occurs as two separate independent processes.In this paper, we reconsider the combined acceleration mechanism by introducing a kinetic-dynamic-hydro full-coupled model instead of the original micro-kinetic or macro-dynamic model.We investigate different acceleration mechanisms in the vicinity of neutral points in magnetic islands evolution, from the stage of shrink and breakup into smaller islands(kinetic scale), to the stage of coalescence and growth into larger islands(dynamic scale), to the stages of constant and quasi-constant(contracting-expanding) islands(hydro scale).As a result, we give for the first time the acceleration efficiencies of different types of acceleration mechanisms in magnetic islands' interactions in solar atmosphere LTSTMR activities(pico-, 10^(–2)–10~5 m; nano-, 10~5–10~6 m; micro-, 10~6–10~7 m; macro-, 10~7–10~8 m; large-,10~8–10~9 m).A new combined Fermi, betatron, and turbulent electron acceleration mechanism is proposed in interaction of magnetic islands during turbulent magnetic reconnection evolution in explosive astrophysical phenomena at large temporal-spatial scale(LTSTMR), the ratio of observed current sheets thickness to electron characteristic length, electron Larmor radius for low-β and electron inertial length for high-β, is on the order of 10^(10)–10^(11); the ratio of observed evolution time to electron gyroperiod is on the order of 10~7–10~9).The original combined acceleration model is known to be one of greatest importance in the interaction of magnetic islands; it assumes that the continuous kinetic-dynamic temporal-spatial scale evolution occurs as two separate independent processes.In this paper, we reconsider the combined acceleration mechanism by introducing a kinetic-dynamic-hydro full-coupled model instead of the original micro-kinetic or macro-dynamic model.We investigate different acceleration mechanisms in the vicinity of neutral points in magnetic islands evolution, from the stage of shrink and breakup into smaller islands(kinetic scale), to the stage of coalescence and growth into larger islands(dynamic scale), to the stages of constant and quasi-constant(contracting-expanding) islands(hydro scale).As a result, we give for the first time the acceleration efficiencies of different types of acceleration mechanisms in magnetic islands' interactions in solar atmosphere LTSTMR activities(pico-, 10^(–2)–10~5 m; nano-, 10~5–10~6 m; micro-, 10~6–10~7 m; macro-, 10~7–10~8 m; large-,10~8–10~9 m).

关 键 词：hybrid PARTICLE ACCELERATION mechanism LARGE temporal-spatial TURBULENT magnetic RECONNECTION Hydro-Dynamic-Kinetic model 

分 类 号：P[天文地球]