HR: 0800h AN: SM51C-1836 Poster TI: High-Lundquist Number Resistive MHD Simulations of Turbulent Magnetic Reconnection with Secondary Island Formation and Enhanced Reconnection Rate AU: *Ragunathan, S EM: [email protected] AF: Geophysical Institute, UAF, Fairbanks, AK, USA AU: Ng, C EM: [email protected] AF: Geophysical Institute, UAF, Fairbanks, AK, USA AB: We present our latest...

It has been recognized that magnetic reconnection process is of great importance in high-energy astrophysics. We develop a new two-dimensional relativistic resistive magnetohydrodynamic (RMHD) code, and carry out numerical simulations of magnetic reconnection. We find that outflow velocity reaches Alfvén velocity in the inflow region, and that higher Alfvén velocity provides higher reconnection...

In this Chapter we review a new and rapidly growing area of research in high-energy plasma astrophysics — radiative magnetic reconnection, defined here as a regime of reconnection where radiation reaction has an important influence on the reconnection dynamics, energetics, and/or nonthermal particle acceleration. This influence be may be manifested via a variety of radiative effects that are cr...

*Correspondence: Rudolf A. Treumann, International Space Science Institute Bern, Hallerstrasse 6, CH-3012 Bern, Switzerland e-mail: [email protected] Magnetic reconnection, the merging of oppositely directed magnetic fields that leads to field reconfiguration, plasma heating, jetting and acceleration, is one of the most celebrated processes in collisionless plasmas. It requires the violation...

The most important goal in magnetic reconnection research is to explain the fast magnetic reconnection phenomena observed in nature. The Hall effect has been found to drive fast magnetic reconnection in 2D numerical simulations [1]. An out-of-plane quadrupole magnetic field found in these numerical simulations [2,3] is the hallmark of the Hall effect. This quadrupole magnetic field has been obs...

We derive restrictions on collisional reconnection under the conditions in near-Earth space. The arguments are based on the precise definition and estimates of the resistive scale Lη at the ion inertial site in collisionless reconnection, i.e. in the so-called ‘ion diffusion region’ which is the region of Hall-current flow. Introduction. – Collisional magnetic reconnection is fast only in insul...

Submitted for the DPP09 Meeting of The American Physical Society Unsteady reconnection in MHD models GIOVANNI LAPENTA, KU Leuven — Within a MHD approach we find magnetic reconnection to progress in two entirely different ways. The first is well known: the laminar Sweet-Parker process. But a second, completely different and chaotic reconnection process is possible [1]. This regime has properties...

Turbulent reconnection allows fast magnetic reconnection of astrophysical magnetic fields. This entails numerous astrophysical implications and opens new ways to approach long standing problems. I briefly discuss a model of turbulent reconnection within which the stochasticity of 3D magnetic field enables rapid reconnection through both allowing multiple reconnection events to take place simult...

Reconnection rate is found for the canonical simplest case of steadystate two-dimensional symmetric reconnection in an incompressible plasma by matching of outer Petschek solution and internal diffusion region solution. The reconnection rate obtained naturally incorporates both Sweet–Parker and Petschek regimes, the latter seems to be possible only for the case with strongly localized resistivity.

Reconnection rate is found for the canonical simplest case of steadystate two-dimensional symmetric reconnection in an incompressible plasma by matching of outer Petschek solution and internal diffusion region solution. The reconnection rate obtained naturally incorporates both Sweet–Parker and Petschek regimes, the latter seems to be possible only for the case with strongly localized resistivity.