SM54A-06
The importance of kinetic ion physics in the interaction of magnetic islands
Friday, 18 December 2015: 17:15
2016 (Moscone West)
Adam Stanier1, William S Daughton2, Luis Chacon1, Homayoun Karimabadi3, Jonathan Ng4, Amitava Bhattacharjee4, Yi-Min Huang5 and Ammar Hakim5, (1)Los Alamos National Laboratory, Los Alamos, NM, United States, (2)Los Alamos National Laboratory, Plasma Theory and App, Los Alamos, NM, United States, (3)University of California San Diego, La Jolla, CA, United States, (4)Princeton University, Princeton, NJ, United States, (5)Princeton University, Princeton Plasma Physics Laboratory, Princeton, NJ, United States
Abstract:
The island coalescence problem is a simple reconnection test problem that includes many key features of real reconnecting systems; the formation of the current layer, the build-up of magnetic energy, and the onset and cessation of reconnection. A recent fully kinetic study found the average reconnection rate to decrease steeply with system-size, but no explanation was given and it remained unclear whether such results can be reproduced in two-fluid models such as Hall-MHD. Here we show that Hall-MHD is unable to reproduce the equivalent fully kinetic results, and that ion kinetic physics is necessary to describe the peak and average rates, pile-up field, outflow velocity, and global evolution of the system. This work suggests the importance of approximating such kinetic ion physics in global simulation models, in order to properly model reconnection events.
