K/π and p/π Fluctuations in Au+Au Collisions in STAR
Abstract
The freeze-out of an extended, strongly-interacting system created in a relativistic heavy ion collision near the QCD critical endpoint could create observable non-statistical fluctuations in net charge, strangeness and baryon number. We present results for K/π and p/π fluctuations from central Au+Au collisions at √sNN = 20, 62.4, 130, and 200 GeV in terms of the variable σdyn. We compare these results with recent data from NA49 [1] for central Pb-Pb collisions. The energy dependence of the present data for central collisions extends smoothly from the NA49 measurements. We present the centrality dependence of K/π and p/π fluctuations from Au+Au collisions at √sNN = 62.4 and 200 GeV in terms of the variable νdyn,Kπ . To minimize contributions from background protons, we restrict our measurements for p and p to the transverse momentum range 0.4 < pt< 1.0 GeV/c. We present results for K/π and p/π fluctuations separated by sign as a function of centrality. In addition, we present results for net charge fluctuations (&+circ;/&-circ;), net strangeness fluctuations (K^+/K^-), and net baryon fluctuations (p/p). We compare our results with the predictions of the Statistical Hadronization, HIJING, UrQMD, and HSD models.[4pt] [1] T. Anticic et al., Phys. Rev. C 79, 044910 (2009).
- Publication:
-
APS Meeting Abstracts
- Pub Date:
- October 2009
- Bibcode:
- 2009APS..HAW.EB008W