Authors: Chris Crawford (The University of Alabama in Huntsville), Haihong Che (The University of Alabama in Huntsville)

A new nonlinear magnetic reconnection (MR) acceleration mechanism was recently brought forward, in which electrons are accelerated by an electron Kelvin-Helmholtz instability (EKHI), which is driven by inherent electron velocity shear in a force-free current sheet during magnetic reconnection with a strong guide field. We use three particle-in-cell simulations of increasingly larger domain size to conduct an analysis of the impact of domain size on the mechanism. We found that with the increase in domain size, the MR timescale increases due to an increase in magnetic energy stored in the current sheet. We demonstrate that the temporal scale of the linear and nonlinear growth stages of the EKHI are minimally affected by the increase of domain size while the temporal scale of the quasi-saturation stage increases with the domain size. Then we find the temporal evolution of the electron energy power law index which demonstrates a soft to hard to harder (SHH) evolution from \gamma ~ 7 to \gamma ~ 3 similar to observations of GOES solar flares.