MHD Simualtions: Energization of charged particles by fast magnetic reconnection


We study the role of turbulence in magnetic reconnection, within the framework of magnetohydrodynamics, using three-dimensional direct numerical simulations. For small turbulent intensity, we find that the reconnection rate obeys Sweet–Parker scaling. For large enough turbulent intensity, reconnection rate departs significantly from Sweet–Parker behaviour, becomes almost a constant as a function of the Lundquist number. We further study energization of test-particles in the same set-up. We find that the speed of the energized particles obeys a Maxwellian distribution, whose variance also obeys Sweet–Parker scaling for small turbulent intensity but depends weakly on the Lundquist number for large turbulent intensity. Furthermore, the variance is found to increase with the strength of the reconnecting magnetic field.
This is based on the paper by
Sharma, Rohit; Mitra, Dhrubaditya; Oberoi, Divya
ISSN: 0035-8711 , 1365-2966; DOI: 10.1093/mnras/stx1291
Monthly notices of the Royal Astronomical Society. , 2017, Vol.470(1), p.723-731