Comparison of the H07 template and the best fitting models, assuming different upper cut-offs to the light curve. In each case, we assume first detection occurs ∼1 d after explosion. Points included in the χ² analysis are shown as solid circles. Unfilled circles show the remainder of the light curve for reference. Panel a: best matching model parameters are given when fitting the full light curve of the H07 template, up to close to maximum light. Panel b: best matching model parameters when fitting only less than the first two weeks of the light curve. Panel c: only the first week of the light curve is included in the χ² analysis, again showing how the data included in the comparison can affect the results. Panels d and e: ⁵⁶Ni distributions for the best fitting models in mass- and velocity-space, assuming different upper cut-offs to the template light curve.