Jet reconstruction in heavy ion collisions (emphasis on Underlying Event background subtraction)

Abstract

A modification of the internal structure of jets is expected due to the production of a dense QCD medium, the Quark Gluon Plasma, in heavy-ion collisions. We discuss some aspects of jet reconstruction in p+p and A+A collisions and emphasize the dramatically increased contribution of the underlying event in nucleus-nucleus collisions as compared with the vacuum case. We conclude with its consequences on the full jet spectrum and fragmentation function extraction at LHC.

10 pages, talk given at First International Workshop on Multiple Partonic Interactions at the LHC, "MPI@LHC'08", Perugia, Italy, October 27-31 2008