Abstract
A numerical study of magnetic reconnection in the large-Lundquist-number (S), plasmoid-dominated regime is carried out for S up to 10(7). The theoretical model of Uzdensky et al. [Phys. Rev. Lett. 105, 235002 (2010)] is confirmed and partially amended. The normalized reconnection rate is (E) over tilde (eff) similar to 0: 02 independently of S for S >> 10(4). The plasmoid flux (Psi) and half-width (w(x)) distribution functions scale as f(Psi) similar to Psi(-2) and f (w(x)) similar to w(x)(-2). The joint distribution of Psi and w(x) shows that plasmoids populate a triangular region w(x) greater than or similar to Psi/B-0, where B-0 is the reconnecting field. It is argued that this feature is due to plasmoid coalescence. Macroscopic "monster" plasmoids with w(x) similar to 10% of the system size are shown to emerge in just a few Alfven times, independently of S, suggesting that large disruptive events are an inevitable feature of large-S reconnection. [http://dx.doi.org/10.1063/1.3703318]