Jet quenching with ATLAS and CMS

An overview of the most recent results on jet quenching physics obtained using Pb-Pb collision data collected with the ATLAS and the CMS experiments at √(NN)=2.76 TeV will be presented. These measurements make use of many different observables, including momentum imbalance of di-jet and photon-jet events, nuclear modification factors R_AA and R_CP, as well as jet fragmentation functions, jet shapes, and the flavor dependence of jet quenching. The measurements in Pb-Pb collisions will be compared to those obtained from pp collisions at the same center-of-mass energy. The effects of the parton energy loss in the hot and dense medium probed with the different observables will be discussed. In summary, the fraction of di-jets in which the momentum of the leading and sub-leading jets are significantly unbalanced, rises dramatically for more central Pb-Pb collisions, consistent with significant quenching of hard partons. A large fraction of the momentum 'missing' from the lower energy jet is carried by low-p_T particles at relatively large angles with respect to the jet axis. The photon-jet correlation studies support the di-jet quenching picture further. Measurement of b-jets shows that the heavy quark jets are quenched similar to light quark jets, with no strong dependence on jet p_T. A clear centrality dependent modification of the inclusive jet rates, shapes and fragmentation function in Pb-Pb collisions is now revealed