Friday, September 2, 2016
Frontiers of magnetic reconnection research will be discussed by highlighting a few recent achievements primarily from laboratory experiments but also from theory and numerical simulations. Of particular importance among these achievements is the development of a reconnection “phase diagram”, in which different coupling mechanisms from the global system scale to the local dissipation scale are classified into different reconnection phases [H. Ji & W. Daughton, Phys. Plasmas 18, 111207 (2011)]. In addition to the traditional single X-line regimes, the new regimes involve multiple X-lines, directly relevant to heliophysical, astrophysical, and fusion plasmas, are illustrated in the phase diagram, based on the theoretical breakthrough on the secondary tearing instability of reconnecting current sheets [N. Loureiro, A. Schekochihin, & S. Cowley, Phys. Plasmas 14, 100703 (2007)]. This progress motivated a major next-step laboratory device, called the Facility for Laboratory Reconnection Experiments or FLARE (flare.pppl.gov), which is currently under construction at Princeton. The goal of the FLARE project is to provide access to the multiple X-lines reconnection regimes. The currently existing small-scale experiments have been focusing on the single X-line reconnection process in plasmas either with small effective sizes and/or at low Lundquist numbers, both of which however are typically very large in natural and fusion plasmas. The design of the FLARE device is based on the existing Magnetic Reconnection Experiment (MRX) (mrx.pppl.gov). The motivating frontier physics questions for FLARE, its construction status, and the planned collaborative research with heliophysics, astrophysics and fusion communities as a user facility will be discussed in details.