The Relativistic Heavy Ion Physics group is led by Christine Nattrass, Ken Read, and Soren Sorensen and typically involves several postdocs and 4-5 graduate students. The main focus of our research is to study the properties of nuclear matter at high temperatures and densities where it will undergo a phase transition to a Quark Gluon Plasma (QGP) consisting of quarks and gluons. Our experimental studies are taken place within the ALICE Collaboration at the Large Hadron Collider (LHC) at CERN, Geneva, Switzerland and the PHENIX Collaboration at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory, New York. The Quark Gluon Plasma was discovered at RHIC and later confirmed at the LHC. Surprisingly it behaves more like a superfluid gluon liquid with a smaller specific viscosity than any other material known. Our group has performed measurements of the energy density of the QGP and the interaction of fast heavy quarks, like charm and bottom quarks, with the surrounding QGP. We have also started a program in studies of the remnants of high energy quark and gluons moving through the QGP (jets). The common theme for all our measurements is to provide information that will enable us to better understand the many-body aspects of the fundamental theory, Quantum Chromo Dynamics, that describe the strong nuclear force.
Our group has for more than three decades worked in close collaboration with groups at Oak Ridge National Laboratory (ORNL) on the development of novel large-scale detectors and electronics as well as the analysis of experimental data. For the next several years we will be heavily involved in the upgrade of the ALICE detector together with ORNL and 8 other American institutions. We have also utilized the leadership computers at ORNL for hydrodynamics studies of the expansion of the QGP and we will continue to explore the opportunities for using these computers for the analysis of the data from the LHC.