Electron and ion particle velocity distribution functions for guide-field cases of 0B_P and 0.6B_P in the 3D simulation runs. The black lines show the distribution functions at the beginning of the respective simulation. The dark grey lines show the distribution functions when peak reconnection currents were reached, which occurred in both guide-field cases at around t = 375 /ω_pe. The light grey lines show distribution functions at the end of the simulation, i.e. t = 500 /ω_pe. The particles included in the plots were chosen from an area around the diffusion region, i.e. (− 2c/ω_pe) <x< (2c/ω_pe) and (− 8c/ω_pe) <y< (8c/ω_pe).