Stellar velocity dispersion profile of the main deflector. The apertures (the first 0.4″-radius aperture and then different annuli with the same center) used to extract the spectra relative to each bin are shown in the inset. In the bottom panel, we show the spectral S/N of each bin, which is larger than 15 in all of them, peaking at around 60. Given the value of the observational PSF FWHM and of the chosen bin widths, the σ_⋆ values of the profile are partially correlated.