SN 2011dh (dereddened and redshift corrected) at 99 days (top), 202 days (second panel), 293 days (third panel), and 415 days (bottom) (red) and model 12C at 100, 200, 300, and 400 days (black), scaled with exponential factors exp(−2Δt/ 111.4), where Δt is the difference between observed and modelled phase (here Δt = −1, +2, −7, +15 days). The decay rate of double the ⁵⁶Co rate corresponds to the flux evolution in most photometric bands (E14b). The most distinct emission lines are labelled with their dominant contributing element in the model.