ASCR/NP LQCD SciDAC Project

The Lattice Quantum Chromo-Dynamics (LQCD) ASCR/NP SciDAC Project is supported by the U.S. Dept. of Energy Office of Nuclear Physics and the Office of Advanced Scientific Computing Research. This SciDAC project focuses on an ambitious program of theoretical, algorithmic and software development which will enable calculations using lattice Quantum Chromodynamics (LQCD) methods to exploit the new generation of leadership-class resources and dedicated hardware to address fundamental questions in nuclear science. Specifically, our project will impact our understanding of results from current heavy ion experiments at the Relativistic Heavy-Ion Collider (RHIC), the study of excited and exotic states of hadrons at CLAS-12 and GlueX at Jefferson Lab (JLab) and the hadron and nuclear structure programs at RHIC-spin and JLab. The calculations that are enabled by the proposed developments will also look forward to experiments on protons and nuclei at the upcoming Electron-Ion Collider (EIC).

News

	Drilling into Neutron Stars with Computers APS Viewpoint - 2025 Simulations of neutron stars provide new bounds on their properties, such as their internal pressure and their maximum mass.
	Inside the box - look at excited hadrons could help solve mystery of particle X3872 Jefferson Lab Highlight - 2024 Lattice QCD method suggests a simpler spectrum of exotic XYZ hadrons
	Gravitational Form Factors Illuminate Substructure of the Proton Berkeley Lab Highlight - 2024 Using simulations performed on NERSCs Perlmutter system, a team of researchers from Fermi National Laboratory; the Massachusetts Institute of Technology; the University of California, Berkeley; and the Nuclear Science Division at Lawrence Berkeley National Laboratory used LQCD to understand for the first time certain aspects of proton structure in terms of its fundamental quark and gluon constituents.
	Pooling skills to study a slippery particle Jefferson Lab Highlight - 2024 A combination of supercomputing and traditional techniques allowed Jefferson Lab theorists to better describe the unstable sigma meson particle, contributing to our comprehension of the strong interaction
	Calculation Sharpens Imaging of Protons Insides DOE SC Highlight - 2024 Nuclear scientists used a new theoretical approach to calculate a value essential for unraveling the three-dimensional motion of quarks within a proton.
	To Understand a Special Hadron, Researchers Turn to Supercomputers and Quantum Chromodynamics DOE SC Highlight - 2024 Scientists Gain new insights into the nature of the puzzling lambda 1405 hyperon resonance and its controversial partner.
	Scientists calculate predictions for EIC measurements Brookhaven National Lab Highlight - 2024 Nuclear theorists used supercomputer calculations to accurately predict the distribution of electric charges in mesons, particles made of a quark and an antiquark.
	Theory and experiment combine to shine a new light on proton spin Jefferson Lab Highlight - 2024 Nuclear physicists have long been working to reveal how the proton gets its spin. Now, a new method that combines experimental data with state-of-the-art calculations has revealed a more detailed picture of spin contributions from the very glue that holds protons together. It also paves the way toward imaging the protons 3D structure.
	Calculation Shows Why Heavy Quarks Get Caught Up in the Flow DOE SC Highlight - 2023 The calculation will help scientists explain experimental results showing heavy quarks getting caught up in the flow of matter generated in heavy ion collisions.
	Theory Offers a High-Resolution View of Quarks Inside Protons DOE SC Highlight - 2023 Protons contain two up quarks and one down quark. New calculations predicting the spatial distributions of the charges, momentum, and other properties of the quarks within protons revealed key differences between the up and down quarks.
	Nuclear Physics Gets a Boost for High-Performance Computing HPC Wire - 2022 Efforts to harness the power of supercomputers to better understand the hidden worlds inside the nucleus of the atom recently received a big boost.
	How US supercomputers will next model elementary particles The Register - 2022 If todays tech gets you down, remember supercomputers are still being used for scientific progress
	Nuclear Physics Gets a Boost for High-Performance Computing Jefferson Lab Highlight - 2022 Jefferson Lab and its partners benefit from Scientific Discovery through Advanced Computing Partnership in Nuclear Physics grants
	For the First Time, Scientists Rigorously Calculate Three-Particle Scattering from Theory DOE Office of Science Highlight - 2022 The goal of nuclear physics is to describe all matter from its simplest building blocks: quarks and gluons. Found deep inside protons and neutrons, quarks and gluons also combine in less common configurations to make other subatomic particles of matter. For scientists, producing these less-common particles in experiments is an interesting challenge. A new theory method aids in those efforts by predicting which less-common particles an experiment will produce.
	NERSC's Cori System Reveals Integral Role of Gluons in Proton Pressure Distribution NERSC Highlight, 2019-07-08 For the first time, lattice QCD calculations run at NERSC allowed nuclear physicists to determine the pressure distribution inside a proton, taking into account the contributions of the proton’s fundamental particles: quarks and gluons. This discovery brings nuclear scientists closer to a complete understanding of a proton’s structure and the fundamental particles that make up most of the visible matter in the universe.
	MG Proto: Multigrid LQCD Propagators for Multicore x86 systems SciDAC Highlight, 2019-05-16 A new multi-grid implementation for x86 architectures with supporting AVX512 instructions, such as Intel Xeon Phi Knight's Landing, and Xeon Servers (Skylake and beyond) speeds up calculations by 7x-8x accelerating calculations on platforms such as NERSC Cori KNL, ALCF Theta, TACC Stampede 2 and the Jefferson Lab SciPhi Cluster.
	Summit speeds calculations in the search for exotic particles OLCF Highlight, 2018-09-17 The accelerated architecture of America’s fastest supercomputer boosts QCD simulations
	Accelerating QCD Gauge Generation on GPUs SciDAC Highlight, 2018-05-01 The generation of gauge configurations (samples of the strong force field in the vacuum) is the gating first step of nuclear and high energy physics calculations using lattice quantum chromodynamics (LQCD) generating the data on which subsequent calculations depend. Here, we demonstrate a 73x reduction in the GPU-hours required for the generation of such gauge fields moving from Titan to Summit, and incorporating new algorithms well suited to the new system. The improvement on Summit enables calculations which where hitherto considered out-of reach for reasons of computational cost, and will fundamentally re-shape how we will conduct our scientific campaigns in the future.