The science and programs of the High-Energy-Density Science Center at LLNL
Frank Graziani, Lawrence Livermore National Laboratory

High energy density physics (HEDP) is the study of matter at extreme conditions where energy densities are in excess of 10^12 ergs/cc  or equivalently, pressures are in excess of 1 Mbar.  HEDP spans a wide range of phenomena, from the deep interiors of the giant planets to the hot plasmas typical of stellar interiors. Matter in the HEDP regime can involve some combination of the following phenomena, collective effects, electron degeneracy, radiation, atomic kinetics, strong particle-particle correlations, non-equilibrium and hybrid quantum-classical behavior. In this talk I focus on an important component of executing experiments at any HEDP facility-simulation. I discuss the spectrum of computational approaches HEDP scientists use to model their experiments, from hydrodynamics, to kinetic theory to particle based methods. I discuss the strengths and weaknesses of the various computational approaches and briefly touch on two recent advances that may hold promise to enhancing the current weaknesses. The talk ends with a discussion of the High Energy Density Sciences Center, which is an outreach organization at LLNL that is building a HEDP community through interactions of LLNL scientists withacademic collaborators.