Centrality and pseudorapidity dependence of the transverse energy flow in pPb collisions at sqrt(s_NN) = 5.02 TeV

Abstract

The almost hermetic coverage of CMS is used to measure the distribution of transverse energy as a function of pseudo-rapidity for pPb collisions at $\sqrt{s_{NN}} = 5.02$ TeV. For minimum bias collisions $(1/N)~dE_T/d\eta$ reaches 23 GeV which implies an $E_T$ per participant pair comparable to that of peripheral PbPb collisions at $\sqrt{s_{NN}} = 2.76$ TeV. The centrality dependence of transverse energy production has been studied using centrality measures defined in three different angular regions. There is a strong auto-correlation between $(1/N)~dE_T/d\eta$ and the $\eta$ range used to define centrality %both for data and the EPOS-LHC and HIJING event generators. The centrality dependence of the data is much stronger for $\eta$ values on the lead side than the proton side and shows significant differences from that predicted by either event generator.