Scaling of particle and transverse energy production in $^{208}$Pb+$^{208}$Pb collisions at 158$\cdot A$ GeV

Abstract.

Transverse energy, charged particle pseudorapidity distributions and photon transverse momentum spectra have been studied as a function of the number of participants ($N_{part}$) and the number of binary nucleon-nucleon collisions ($N_{coll}$) in 158$\cdot A$ GeV Pb+Pb collisions over a wide impact parameter range. A scaling of the transverse energy pseudorapidity density at midrapidity as $\sim N_{part}^{1.08 \pm 0.06}$ and $\sim N_{coll}^{0.83 \pm 0.05}$ is observed. For the charged particle pseudorapidity density at midrapidity we find a scaling as $\sim N_{part}^{1.07 \pm 0.04}$ and $\sim N_{coll}^{0.82 \pm 0.03}$. This faster than linear scaling with $N_{part}$ indicates a violation of the naive Wounded Nucleon Model.