Colour plot (position vs. time) of the energy stored in the different electric field components. As an indication, lines with squares represent the propagation of structures at different speeds. From the most horizontal line to the most vertical one (with squares): speed of light in vacuum, thermal speed of the electrons , and ion acoustic speed . The vertical line with circles is located at 0.5 L_box, where B_z is originally B₀/2. The colour bar is in logscale (different for each plot) and SMILEI units (here n₀m_ec²).