Best fit (solid blue line) of the bolometric luminosity (red dots) with the code LC2 by Nagy et al. (2014) with a shell component (dotted green line) and a core+magnetar component (dash-dotted cyan line). The model does not provide a satisfactory power explanation for the peak, which requires an additional source (see text). An alternative fit with a core+Ni component, which yields a worse fit than the magnetar, is also plotted with a dashed magenta line.