Notes. We report the outcome of the nested sampling exploration performed with MULTINEST for each lens and density profile model, in terms of mean values and the 95 percent confidence interval. The corresponding posterior distributions are shown in Figs. 2, 3 and 4. The significance of the detection is expressed by the difference in Bayesian evidence to the smooth model (third column): a positive difference indicates that the perturbed model is preferred. The PJ profile is defined by the subhalo mass, M_sub, which also characterises the NFW profile together with the subhalo concentration, c_sub. In the NFW fix case, the concentration is determined by the concentration–mass–redshift relation from Duffy et al. (2008), and the value reported here corresponds to the mean inferred M_sub, while the error is propagated from the uncertainty on the mass. The PL profile is instead expressed in terms of normalised convergence, κ_sub, and the slope of the profile, γ_sub.