Multi-hierarchy physics in magnetic reconnection is investigated using two kinds of numerical simulation models: the electromagnetic particle simulation model for an open system (PASMO) and the magnetohydrodynamic and particle-in-cell (MHD-PIC) interlocked model for the multi-hierarchy simulation of magnetic reconnection. A series of simulation studies using the PASMO code have disclosed that ion and electron dissipation regions form inside a kinetic regime in which ion and electron meandering orbit effects are crucial in triggering collisionless reconnection (CR). Anomalous resistivity leading to CR is also generated through the excitation of ion-ion kink instability in an ion-scale current sheet. We confirmed that the MHD-PIC interlocked model, based on the domain decomposition and multi-time-step methods, can describe collisionless driven reconnection in an open system as a multi-hierarchy phenomenon with high accuracy.
2010 by The Japan Society of Plasma Science and Nuclear Fusion Research