Session H17: Invited Session: The Impact of Advanced Digital Resources on Research in Physics

Unearthing the excited hadron resonances in lattice QCD using NSF XSEDE resources

Recent advances in computational techniques in lattice QCD, combined with the formidable capabilities of NSF XSEDE computing and data management resources, has enabled unprecedented access for theoretical studies to QCD excited states. First results of stationary-state levels in several symmetry sectors using very large sets of both single-meson and two-meson operators are presented. Our results are obtained in large volumes using quark masses producing a pion mass of 240 MeV, nearing the physical limit. Level identification using probe operators is discussed.   

Petascale Simulations of Core-Collapse Supernovae

Core-collapse supernovae from massive stars are among the most energetic events in the universe. They liberate a mass-energy equivalent of $\sim$15\% of a solar mass in the collapse of their progenitor star's core. The majority ($\sim$99\%) of this energy is carried away by neutrinos, while $\sim$1\% is transferred to the kinetic energy of the explosive outflow. A smaller, yet still tremendous amount of energy is emitted in electromagnetic and gravitational waves. Core collapse and the subsequent supernova evolution towards explosion involve a broad range of physics: Boltzmann transport of neutrinos, weak interactions, nuclear reactions, the nuclear equation of state, magnetohydrodynamics, and gravity. The problem is also multi-scale and for modeling the supernova engine, one must generally resolve physical scales from $\sim$10000 km down to below $\sim$100 m. Due to its multi-physics multi-scale nature, the core-collapse supernova problem poses a formidable computational challenge that requires petascale resources of the caliber of the NSF BlueWaters system. I review the computational approaches employed by the core-collapse supernova modeling community and present an overview of recent results from the first set of full 3D simulations.