title: Has the QCD critical point been signaled by observations at the BNL relativistic heavy ion collider?
abstract: The shear viscosity to entropy ratio (eta/s) is estimated for the hot and dense QCD matter created in Au+Au collisions at BNL Relativistic Heavy Ion Collider (square root[s_{NN}]=200 GeV). A very low value is found; eta/s approximately 0.1, which is close to the conjectured lower bound (1/4pi). It is argued that such a low value is indicative of thermodynamic trajectories for the decaying matter which lie close to the QCD critical end point.
authors.affiliation: Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794-3400, USA.
authors.forename: Roy A
authors.initials: RA
authors.lastname: Lacey
authors.forename: N N
authors.initials: NN
authors.lastname: Ajitanand
authors.forename: J M
authors.initials: JM
authors.lastname: Alexander
authors.forename: P
authors.initials: P
authors.lastname: Chung
authors.forename: W G
authors.initials: WG
authors.lastname: Holzmann
authors.forename: M
authors.initials: M
authors.lastname: Issah
authors.forename: A
authors.initials: A
authors.lastname: Taranenko
authors.forename: P
authors.initials: P
authors.lastname: Danielewicz
authors.forename: Horst
authors.initials: H
authors.lastname: Stöcker