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NP 621 Seminar; Elton Freeman “Has the QCD Critical Point Been Signaled by Observations at the BNL Relativistic Heavy Ion Collider? Phys. Rev. Lett 98, 092301 (2007) .
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NP 621 Seminar; Elton Freeman“Has the QCD Critical Point Been Signaled by Observations at the BNL Relativistic Heavy Ion Collider? Phys. Rev. Lett 98, 092301 (2007) • Main Point: Viscosity to Entropy Ratio (η/s) has been estimated for a hot and dense quark gluon plasma of ~0.09, close to the lower bound~0.08, this data may lead to mapping out the CEP for the phase diagram.
Hot and Dense Fluid • Historical Fact: Berkley’s SuperHilac, 1984. • Current beam energies of 100 GevA. • Calculated Temp. Tc=170Mev, P=1030 atm • Elliptic Flow patterns give a hint of viscosity.
Lower Bound? • Lacey et al. estimates for QGP:η/s~(Tλc)/197~ 0.09±0.015; for Au + Au Collision close to the lower conjectured bound of 0.079! • Anti-de Sitter Space: estimates η/s~ħ/4πkβ~0.079as lower bound. airXiv:nucl-th/0702007v2 5 Apr 2007 • Constraints on the CEP for future study!