Search this Site

Print this page
RSS

Brookhaven National Laboratory

"Entangled glue or collective flow: a QCD puzzle in particle correlations at RHIC and the LHC"

Raju Venugopalan

Wednesday May 01, 2013

3:30pm PHYS 298

Refreshments are served at 3:15 p.m. in Physics room 298.

Abstract: The LHC is a gluon factory, so much so that very rare proton collision events producing over a hundred charged hadrons have been measured. We argue that a non-trivial correlation amongst the produced charged hadrons (called a "ridge" because of the event structure) in these rare events is due to a subtle quantum interference between gluons emerging from decaying colored flux tubes in the collisions. In nucleus-nucleus collisions, the pressure gradients generated by rescattering of gluons generated by multiple flux tubes overwhelms this subtle quantum effect and produces a much larger ridge structure. Proton-nucleus collisions at the LHC and deuteron-nucleus collisions at RHIC can help unentangle this tangled web. The answers to this question will help us resolve fundamental issues such as i) whether gluons in the proton wavefunction are frozen into states of maximal occupancy before the collision, and ii) the applicability of relativistic hydrodynamics in very small sized systems.


Short Bio: Raju Venugopalan got his Ph. D degree from Stony Brook in 1992. After post-doctoral work at the Theoretical Physics Institute, University of Minnesota, the National Institute for Nuclear Theory in Seattle, and the Niels Bohr Institute in Copenhagen, he joined Brookhaven National Lab in 1998. He received tenure in 2002 and was promoted Senior Scientist in 2007. He currently heads the NT Group at BNL and is also Adjunct Professor at Stony Brook University. Raju was a Danish Research Council Fellow (1997-1998), a Fellow of the Riken-BNL Center (RBRC) (2000-2003), a US Research Fellow of the Humboldt Foundation (2004-2005), and received a Senior Fulbright Specialist Award (2012). He was elected a Fellow of the American Physical Society in 2007.  Raju is  an International Scientific Associate of the LHC DISCOVERY Institute in Copenhagen, serves on the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and is co-Editor of the journal Annals of Physics. Raju's interests are in QCD at high energies, heavy ion collisions, and non-equilibrium quantum field theory.