Heavy ion physics with the CMS experiment at the large hadron collider

The LHC will collide protons at rootS = 14 TeV and lead beams at rootS(NN) 5.5 TeV as well as other AA and pA combinations. The physics program of the compact muon solenoid (CMS) includes the study of heavy ion collisions. The collision energy, much higher than at RHIC, will study the dense partonic system with very hard probes: heavy quarks and quarkonia with emphasis on b and Y, W+/- and Z(0) bosons, high-P-T jets and photons. The production of these particles is likely to be modified, relative to pp collisions, by the presence of the hot medium.