centrarity dependence

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RIKEN-BNL and LBL. and Nu Xu. Model. Masashi Kaneta. Based on Ref[11] and used in Ref.[12-14] Density of particle i is Compute particle densities for resonances (mass


  • , , , , , , f0(980) , a0 (980), h1(1170), b1 (1235), a1 (1260), f2(1270), f1 (1285), (1295), (1300), a2(1320), f0(1370), (1440), (1420), f1 (1420), (1450), f0 (1500), f1 (1510), f2(1525), (1600), 2(1670), (1680), 3(1690), fJ(1710), (1700) K, K*, K1(1270), K1(1400), K*(1410), K0*(1430), K2*(1430), K*(1680)p, n, N(1440), N(1520), N(1535), N(1650), N(1675), N(1680), N(1700)(1232), (1600), (1620), (1700), (1450), (1520), (1600), (1670), (1690), (1385), (1660), (1670), (1530), (1690)Data from RHIC experimentsNow we have many set of data for dN/dy and ratios from RHIC experimentsHowever, the centrality bin selection is not the same among experimentsWe need to adjust ratios as a function of common centrality to combine all of data for centrality dependence of chemical freeze-outAssumptiondN/dy is linearly scaled by Actually, the data looks like that dependence Select one set of centrality binsinterpolate dN/dy for the centrality as a function of Particle combinations for the fitThe chemical freeze-out parameter seems to be sensitive to combination of particle ratios as discussed in Ref.[14]Hence we checked the following six combinations of particle ratios for the fit:(1) p, K, and p(2) p, K, p and L(3) p, K, p, L, f, and X(4) p, K, p, L, K*, f, and X(5) p, K, p, L, f, X, and W(6) p, K, p, L, K*, f, X, and W

    SummaryTch, mq, ms seems to be flat in 130 and 200 GeV Au+Au collisionsTch ~ 150-170MeVmq ~ 10 MeV (small net Baryon density)ms ~ 0 MeV (close to phase boundary)There is a dependence of ratio combinations for the fit parametersthe deviation is