UC Berkeley

The observed inclusive jet suppression in heavy-ion collisions at LHC has a very weak pT dependence over a large range of pT=50–1000GeV and is almost independent of the colliding energy, though the initial energy density of the bulk medium has increased from s=2.76 to 5.02TeV by about 20%. This interesting phenomenon is investigated in the linear Boltzmann transport (LBT) model for jet propagation in an event-by-event 3+1D hydro background. We show that the pT dependence of jet RAA is determined by the initial spectrum in p+p collisions and pT dependence of jet energy loss. Furthermore, jet energy loss distributions for inclusive jet and γ-jet at both LHC energies are extracted directly from experimental data through the state-of-art Bayesian analysis. The averaged jet energy loss has a weak pT dependence and the scaled jet energy loss distributions have a large width, both of which are consistent with the LBT simulations and indicate that jet quenching is caused by only a few out-of-cone jet medium scatterings.