Y.Miake, KPS meeting at Seju, 2004
3
Npart vs Nbinary
lSince nucleus is extended object, centrality of collision plays important role.
lFor comparison with pp or dAu also for centrality study, we need scaling variables.
lNpart;
l# of participant nucleons
lParticle production in hA is prop. to Npart, (Wounded-Nucleon Model)
lNbinary;
l# of binary nucleon-nucleon collisions
lPass through at high energy.
lEvaluation of Npart & Nbinary by Glauber Model.
Participant
Let me start with introducing scaling variables; Npart and Nbinary.
Particle production in pp or pA collisions is known to be proportional to Npart which is known as WNM.
As you can see, Npart grows with b, Nbinary grows faster. In central col., Npart is ~400 and Nbinary is ~>1000.