Final kinetic energies for thermal protons initialised in the parallelogram in the centre of the current sheet at z = 0.0 for t = 8 (panel c), t = 16 (panel d), t = 21 (panel e). The parallelogram is composed of 100 × 100 protons (in Cartesian coordinates in panel b) labelled on the axes. This shows the full energy gain plot in comparison to the current sheet shown in panel a, where J_z is the z-component of the current (also at z = 0.0). The plot is then skewed into a rectangle with a log scaling applied to the energy. The dimensions u and υ represent the particle number initialised along the long and short side of the parallelogram, respectively; (0, 0) represents the particle initialised at the top left and (100, 100) represents the particle initialised at the bottom right; see panel c. The corners [x, y] and dimensions of the parallelograms in code units are as follows (starting at the top left corner, going clockwise): panel c: ([−0.32, +0.72],[+0.32, −0.62],[+0.32, −0.72],[−0.32, +0.62]), length (in x) = 0.64, width (in y) = 0.1; panel d: ([−0.29, +1.45],[+0.29, −1.15],[+0.29, −1.45],[−0.29, +1.15]), length (in x) = 0.58, width (in y) = 0.3; and panel e: ([−0.26, +1.90],[+0.26, −1.30],[+0.26, −1.90],[−0.26, +1.30]), length (in x) = 0.52, width (in y) = 0.6.