Speaker
Rolf scharenberg
(Purdue University)
Description
The Color String Percolation Model (CSPM)[1] is used to determine the equation of state (EOS) of the Quark-Gluon Plasma (QGP) produced in central Au-Au collisions at $\sqrt{s_{NN}}$ = 200 A GeV using STAR data at RHIC.When the initial density of interacting colored strings exceeds the 2D percolation threshold a cluster is formed, which defines the onset of color deconfinement. These interactions also produce fluctuations in the string tension which transforms the Schwinger particle (gluon) production mechanism into a maximum entropy thermal distribution analogous to QCD Hawking-Unruh radiation. The single string tension is determined by identifying the known value of the universal hadron limiting temperature $T_{c}$ = 167.7 $\pm$ 2.6 MeV with the CSPM temperature at the critical percolation threshold parameter $\xi_{c}$ =1.2. At mid-rapidity the initial Bjorken energy density and the initial temperature determine the number of degrees of freedom consistent with the formation of a $\sim$ 2+1 flavor QGP. An analytic expression for the equation of state, the sound velocity $C_{s}^{2}(\xi)$ is obtained in CSPM. The CSPM $C_{s}^{2}(\xi)$ and the bulk thermodynamic values energy density $\varepsilon /T^{4}$ and entropy density $s /T^{3}$ are in
excellent agreement in the phase transition region with recent lattice QCD simulations (LQCD) by the HotQCD Collaboration [2].
[1]. M. A. Braun, C. Pajares, Eu. Phys. J. C16, 349 (2000).
[2].A. Bazavov et al., Phys. Rev. D80, 014504 (2009).
Primary author
Rolf scharenberg
(Purdue University)
