Indications of high pT suppression @ SPS

• Centrality evolution of high pT π0 production at SPS:

• “Collision scaling” in 0-8% central collisions (RAA ~ 1).

• “Cronin” enhancement in peripheral ... and suppression in 1% most central

• Look for onset of suppression at RHIC Au+Au, p+p @ √sNN≈ 20 GeV ?