报告人:Ulrich Heinz, Professor, The Ohio State University 报告时间:10月21日下午4:00 报告地点:郑裕彤讲堂(理学院报告厅) 报告题目:The Quark-Gluon Plasma at RHIC - from discovery to quantitative characterization 报告摘要: The Relativistic Heavy Ion Collider (RHIC) was built to re-create and study in so-called "Little Bangs" the extremely hot and dense matter that filled our entire universe during its first few microseconds after the Big Bang. Operating since 2000, RHIC experiments have produced an impressive body of data which provide compelling evidence for the formation of thermally equilibrated matter at unprecedented temperatures and energy densities -- a "quark-gluon plasma". A surprise has been the discovery that this plasma behaves like an almost perfect fluid, with extremely low viscosity. Theorists had expected a weakly interacting gas of quarks and gluons, but instead we seem to have created a
strongly interacting plasma liquid. The experimental evidence strongly relies on a feature called "elliptic flow" in off-central collisions. I will explain the ideas and measurements which led to these conclusions, and show how they tie relativistic heavy-ion physics into other burgeoning fields of modern physics, such as strongly coupled electromagnetic plasmas, ultracold systems of trapped atoms, and superstring theory.
A second stage of experiments at RHIC and the Large Hadron Collider is under way to turn this qualitative discovery into quantitative statements about the properties of the Quark-Gluon Plasma.
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