High pT @ PHENIX: Summary (II)

• Central Au+Au collisions:

  • Strong suppression (factor ~ 4-5) of p0 and h± (with respect to Ncoll scaling) above pT~ 4 GeV/c.
  • Flat pT dependence of suppression above ~4 GeV/c.
  • Very different behaviour than at lower √s (high pT enhancement).
  • Suppression pattern seemingly gradual with centrality (not yet settled).
  • Departure from Ncoll scaling at a 2-sigma level over 50-60% centrality class: Npart ~ 50, eBjorken ~ 1.2 GeV/fm3.
  • No true Npart scaling.
  • No apparent suppression of (anti)protons up to ~4 GeV/c: “anomalous” p/p ~ 0.8 ratio >> than in p+p and e+e- jet fragmentation.
  • Hadron/meson ~ 1.6 above pT~ 5 GeV/c as in p+p (baryon enhancement limited to pT<5 GeV/c).
  • xT scaling holds for p0 not for hadrons (in limited xT range).

Notes: