Ratio between fully-corrected jet mass distribution for anti-\kt{} jets with $R=0.4$ in central \PbPb{} collisions and minimum bias \pPb{} collisions. The ratio is compared to the ratio of mass distributions of PYTHIA (tune Perugia 2011) at $\sqrt{s}=2.76$ TeV and $\sqrt{s}=5.02$ TeV (width of the band represents the statistical uncertainties)