Contribution of ejecta zones to luminosity at various times. Vertical bars represent individual models and are sorted by the bolometric τ₋₁₅. Panels show the total luminosity emitted by models at various times after explosion. Models are discretised into ten zones, each containing 10% of the ejecta mass, beginning from the outer ejecta. Each zone is coloured to show the contribution towards the total luminosity emitted by the model at each time.