Photon-tagged jet measurements in Pb+Pb collisions with the CMS detector

Presented are the results of a detailed study for a complete simulation of the CMS detectors at the LHC in view of the expected modification of jet fragmentation functions in central Pb+Pb collisions at (s_NN)**0.5=5.5 TeV compared to the vacuum (p+p) case. The study is based on photon-jet events, using the correlation between isolated high-transverse energy (E_T>70 GeV) photons and fully reconstructed jets, based on the information provided by the CMS calorimeters and silicon tracker.