Left: L_X,500−M₅₀₀ relation of the Planck-XMM-Newton archive sample compared to REXCESS, a representative X-ray cluster sample. Luminosity is estimated interior to R₅₀₀ in the [0.1–2.4] keV band, and mass from the M₅₀₀−Y_X,500 relation of Arnaud et al. (2010). The solid red line is the fit to the REXCESS sample only (Pratt et al. 2009). Right: scaled density profiles of the 62 systems in the Planck-XMM-Newton archive sample. Profiles have been corrected for projection and PSF effects as described in the text. Systems classified as cool cores are indicated by blue lines.