Global Results 2. Particle Mult.iplicity and ET vs. centrality [PRL 87, 52301 (2001), PRL 86, 3500 (2001)]

• Nch & ET increase faster than linearly with Npart : onset of hard processes contribution (proportional to # binary inelastic colls.)

• Centrality dependence: Important constraint for particle production models:

  • "Soft + hard" (HIJING), initial-state gluon saturation (KLN), final-state gluon sat. (EKRT)

• <ET >/<Nch> ~ 0.8 GeV independent of centrality (and ~ lower energy WA98 data)