Measurement of dN/dη and dET/dη in PbPb collisions with CMS

The charged particle multiplicity and transverse energy in PbPb collisions at 2.76 TeV nucleon-nucleon center-of-mass energy (sNN) has been measured over a broad range of pseudorapidity (η) and collision centrality using the CMS detector at the LHC. The transverse energy density per unit pseudorapidity (dET/dη) increases faster with collision energy than the charged particle multiplicity dN/dη. This implies that the mean energy per particle is increasing with collision energy. At all pseudorapidities the multiplicity and transverse energy per participating nucleon increases with the centrality of the collision. The ratio of transverse energy per unit pseudorapidity in peripheral to central collisions varies significantly as the pseudorapidity increases from η=0 to |η|=5.0.