ORNL Part of Two SciDAC Computational Nuclear Physics Projects

October 9, 2017

Oct. 9, 2017 — The Big Bang began the formation and organization of the matter that makes up ourselves and our world. Nearly 14 billion years later, nuclear physicists at the Department of Energy’s Oak Ridge National Laboratory (ORNL) and their partners are using America’s most powerful supercomputers to characterize the behavior of objects, from subatomic neutrons to neutron stars, that differ dramatically in size yet are closely connected by physics.

Through the DOE Office of Science’s Scientific Discovery through Advanced Computing (SciDAC) program, which concurrently advances science and supercomputing to accelerate discovery, ORNL is participating in two five-year computational nuclear physics projects.

Collaborators on the first project, the Nuclear Computational Low Energy Initiative (NUCLEI), will calculate properties and reactions of diverse atomic nuclei that are important in earthly experiments and astrophysical environments. Approximately 30 researchers at 12 national labs and universities are slated to share funding of $10 million. Joseph Carlson of Los Alamos National Laboratory (LANL) heads NUCLEI, with Stefan Wild of Argonne National Laboratory as co-director for applied math and computer science and Thomas Papenbrock of the University of Tennessee, Knoxville (UTK) and ORNL as the co-director for physics.

The second project, Towards Exascale Astrophysics of Mergers and Supernovae (TEAMS), partners 32 researchers from 12 national labs and universities. With planned support of $7.25 million, workers will simulate supernovae explosions and neutron-star mergers that create atomic elements heavier than iron and predict signatures of these cataclysms, such as gravitational waves. Raph Hix of ORNL heads TEAMS, with Bronson Messer of ORNL as the computational lead and Chris Fryer of LANL as the science lead.

“There is a nice synergy—NUCLEI is doing pure nuclear physics and TEAMS is, in a sense, doing applied nuclear physics,” said Hix, a nuclear astrophysicist. “We need their nuclear physics to do our astrophysics.”

NUCLEI partners will calculate the structure, reactions, interactions and decays of stable and radioactive nuclei (elements that decay to more stable states) for comparison with results of experiments at DOE facilities such as the Facility for Rare Isotope Beams (FRIB), under construction at Michigan State University. Because astrophysicists need high-quality input about how nuclei really behave, information from NUCLEI and from experiments will be used in TEAMS simulations that explore how nuclei are created under the extreme conditions of dying stars.

For both SciDAC projects, science and computing experts will start from state-of-the-art models, numerical techniques and leadership-class high-performance computers, such as Titan, ORNL’s current workhorse supercomputer, or Summit, coming in 2018.

Calculating key nuclei

How does the strong force bind protons and neutrons into nuclei? How do light atomic nuclei capture neutrons to create heavier elements in stars? What is the nature of the neutrino, which plays crucial roles in radioactive decay and supernovae explosions?

These are some questions NUCLEI researchers will explore using advanced applied mathematics, computer science and physics to describe atomic nuclei. The calculations are computationally costly. “With 100 or more particles, exact solutions became exponentially costly,” Papenbrock said. “New methods enable efficient performance on the fastest supercomputers.”

ORNL’s critical contribution to NUCLEI’s scientific community is the coupled-cluster method, an efficient, systematic expansion of the nuclear wave function with a modest computational cost. Its solution provides detailed insights into the structure and decay of atomic nuclei and nuclear interactions. ORNL’s lead for the NUCLEI collaboration, Gaute Hagen, also leads the development of a flagship code NUCCOR (NUclear Coupled Cluster Oak Ridge). NUCCOR provides a compromise between high accuracy and affordable computer cost.

At ORNL, Hagen, Gustav R. Jansen and George Fann will compute properties of nuclei and their decays. At UTK, a postdoctoral fellow will work with Papenbrock on the project. NUCLEI’s partners at other institutions will bring their own codes, computational methods, and expertise to the project. “Atomic nuclei exhibit very different properties as one goes from the lightest nucleus with a single nucleon—a proton—to the heaviest, consisting of about 240 nucleons [protons or neutrons],” Papenbrock explained. “In this collaboration, we have complementary methods that are good for different nuclei.”

Hagen said, “At Oak Ridge we developed first principles methods that can describe medium mass and heavy nuclei starting from the underlying interactions between nucleons. This is remarkable progress in the field. A decade ago we were computing the structure of oxygen-16, the oxygen we breathe, which [has] 16 nucleons. Today we just submitted a paper on tin-100, which has 100 nucleons.”

NUCLEI researchers will calculate properties of key isotopes, such as calcium-60, which has 20 protons and 40 neutrons, and is therefore more exotic than the common stable isotope in our bones and teeth, calcium-40 (20 protons, 20 neutrons). “Calcium-60 has not been measured yet,” Hagen said. “Nothing’s known. To go to that region—and beyond—would be a major challenge for theory. But eventually we’ll get there with the tools that we’re developing and the computing power that will be coming available to us in this SciDAC period.”

The biggest nucleus the scientists propose to compute from scratch is lead-208. Knowledge gained about what keeps its nucleons together might impact the understanding of superheavy elements beyond lead-208. Moreover, the calculations will complement both present and pending experiments.

The stars in ourselves

“Astrophysics is a quintessentially multi-physics application,” said Hix, who leads the other SciDAC project in which ORNL participates, known as TEAMS. “There are so many facets of physics involved; nobody can be expert in all of it. So we must build teams.”

The members of the TEAMS project will improve models of the deaths of massive stars, called core-collapse supernovae, which disperse chemical elements throughout the galaxies, as well as models of the final hours of the stars’ lives that set the initial conditions for core-collapse supernovae. They will also improve models of the mergers of neutron stars, which create black holes while also dispersing newly formed elements.

Improving the TEAMS simulations will require better microscopic nuclear physics, improving our understanding of the states of nuclear matter and its interactions with neutrinos. TEAMS scientists will also study the consequences of explosions detectable by telescopes and the chemical history of our galaxy, providing observations that can be compared with simulations to validate models.

In core-collapse supernovae, massive stars (10 times the mass of our Sun) build up an iron core surrounded by layers of lighter elements—e.g., silicon, oxygen, carbon, helium, hydrogen. Eventually the iron core collapses to form a neutron star, launching a shock wave.

Since the 1960s, scientists have tried to simulate how this shock wave produces a supernova, starting with one-dimensional models that assumed the star was spherically symmetric. Simulations based on those models rarely resulted in explosions. More recently, with better understanding of the physics and faster computers, researchers started running two-dimensional, and later three-dimensional, core-collapse supernova models with improved physics.

“The behavior in two or three dimensions is completely different and you get the development of big convective regions,” Hix said. “It is neutrino energy delivered to the shock wave by convective flows that ultimately powers up the explosion. The result is an asymmetric explosion that shoots out big plumes.”

The power source that drives this explosion is the newly made neutron star, its Sun-sized mass compressed into a mere 30 kilometers, releasing tremendous energy that is carried away rapidly by neutrinos. Capturing just a small fraction of the escaping neutrinos reenergizes the shockwave, leading to the supernova.

The material that gets shot out into the galaxy by the supernova is available to make the next generation of stars. Elements—the oxygen in your breath, the iron in your blood—are tangible tracers of the chemical evolution of our galaxy all the way back to the Big Bang. “The story your atoms could tell!” Hix exclaimed. “Billions of years ago and thousands of light years away, parts of you have been through supernovae, neutron star mergers and other exotic events, and we can prove it because you carry all of the elements and isotopes that were made there. There’s a tendency when people look at the sky to say, ‘Oh, that’s the universe.’ But the universe is here too,” he said, tapping his chest.

The DOE Office of Science supports TEAMS and NUCLEI, as well as a third SciDAC project, Computing the Properties of Matter with Leadership Computing Resources, which will explore the properties of strongly interacting particles composed of quarks and gluons. As results from these projects become available, they will be coupled with results from the other projects and compared to experiment to provide a more complete understanding of nuclei and their reactions.

UT-Battelle manages ORNL for DOE’s Office of Science. The single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit http://science.energy.gov/.


Source: Oak Ridge National Laboratory

Subscribe to HPCwire's Weekly Update!

Be the most informed person in the room! Stay ahead of the tech trends with industy updates delivered to you every week!

Researchers Scale COSMO Climate Code to 4888 GPUs on Piz Daint

October 17, 2017

Effective global climate simulation, sorely needed to anticipate and cope with global warming, has long been computationally challenging. Two of the major obstacles are the needed resolution and prolonged time to compute Read more…

By John Russell

UCSD Web-based Tool Tracking CA Wildfires Generates 1.5M Views

October 16, 2017

Tracking the wildfires raging in northern CA is an unpleasant but necessary part of guiding efforts to fight the fires and safely evacuate affected residents. One such tool – Firemap – is a web-based tool developed b Read more…

By John Russell

Exascale Imperative: New Movie from HPE Makes a Compelling Case

October 13, 2017

Why is pursuing exascale computing so important? In a new video – Hewlett Packard Enterprise: Eighteen Zeros – four HPE executives, a prominent national lab HPC researcher, and HPCwire managing editor Tiffany Trader Read more…

By John Russell

HPE Extreme Performance Solutions

“Lunch & Learn” to Explore the Growing Applications of Genomic Analytics

In the digital age of medicine, healthcare providers are rapidly transforming their approach to patient care. Traditional technologies are no longer sufficient to process vast quantities of medical data (including patient histories, treatment plans, diagnostic reports, and more), challenging organizations to invest in a new style of IT to enable faster and higher-quality care. Read more…

Intel Delivers 17-Qubit Quantum Chip to European Research Partner

October 10, 2017

On Tuesday, Intel delivered a 17-qubit superconducting test chip to research partner QuTech, the quantum research institute of Delft University of Technology (TU Delft) in the Netherlands. The announcement marks a major milestone in the 10-year, $50-million collaborative relationship with TU Delft and TNO, the Dutch Organization for Applied Research, to accelerate advancements in quantum computing. Read more…

By Tiffany Trader

Intel Delivers 17-Qubit Quantum Chip to European Research Partner

October 10, 2017

On Tuesday, Intel delivered a 17-qubit superconducting test chip to research partner QuTech, the quantum research institute of Delft University of Technology (TU Delft) in the Netherlands. The announcement marks a major milestone in the 10-year, $50-million collaborative relationship with TU Delft and TNO, the Dutch Organization for Applied Research, to accelerate advancements in quantum computing. Read more…

By Tiffany Trader

Fujitsu Tapped to Build 37-Petaflops ABCI System for AIST

October 10, 2017

Fujitsu announced today it will build the long-planned AI Bridging Cloud Infrastructure (ABCI) which is set to become the fastest supercomputer system in Japan Read more…

By John Russell

HPC Chips – A Veritable Smorgasbord?

October 10, 2017

For the first time since AMD's ill-fated launch of Bulldozer the answer to the question, 'Which CPU will be in my next HPC system?' doesn't have to be 'Whichever variety of Intel Xeon E5 they are selling when we procure'. Read more…

By Dairsie Latimer

Delays, Smoke, Records & Markets – A Candid Conversation with Cray CEO Peter Ungaro

October 5, 2017

Earlier this month, Tom Tabor, publisher of HPCwire and I had a very personal conversation with Cray CEO Peter Ungaro. Cray has been on something of a Cinderell Read more…

By Tiffany Trader & Tom Tabor

Intel Debuts Programmable Acceleration Card

October 5, 2017

With a view toward supporting complex, data-intensive applications, such as AI inference, video streaming analytics, database acceleration and genomics, Intel i Read more…

By Doug Black

OLCF’s 200 Petaflops Summit Machine Still Slated for 2018 Start-up

October 3, 2017

The Department of Energy’s planned 200 petaflops Summit computer, which is currently being installed at Oak Ridge Leadership Computing Facility, is on track t Read more…

By John Russell

US Exascale Program – Some Additional Clarity

September 28, 2017

The last time we left the Department of Energy’s exascale computing program in July, things were looking very positive. Both the U.S. House and Senate had pas Read more…

By Alex R. Larzelere

US Coalesces Plans for First Exascale Supercomputer: Aurora in 2021

September 27, 2017

At the Advanced Scientific Computing Advisory Committee (ASCAC) meeting, in Arlington, Va., yesterday (Sept. 26), it was revealed that the "Aurora" supercompute Read more…

By Tiffany Trader

How ‘Knights Mill’ Gets Its Deep Learning Flops

June 22, 2017

Intel, the subject of much speculation regarding the delayed, rewritten or potentially canceled “Aurora” contract (the Argonne Lab part of the CORAL “ Read more…

By Tiffany Trader

Reinders: “AVX-512 May Be a Hidden Gem” in Intel Xeon Scalable Processors

June 29, 2017

Imagine if we could use vector processing on something other than just floating point problems.  Today, GPUs and CPUs work tirelessly to accelerate algorithms Read more…

By James Reinders

NERSC Scales Scientific Deep Learning to 15 Petaflops

August 28, 2017

A collaborative effort between Intel, NERSC and Stanford has delivered the first 15-petaflops deep learning software running on HPC platforms and is, according Read more…

By Rob Farber

Oracle Layoffs Reportedly Hit SPARC and Solaris Hard

September 7, 2017

Oracle’s latest layoffs have many wondering if this is the end of the line for the SPARC processor and Solaris OS development. As reported by multiple sources Read more…

By John Russell

US Coalesces Plans for First Exascale Supercomputer: Aurora in 2021

September 27, 2017

At the Advanced Scientific Computing Advisory Committee (ASCAC) meeting, in Arlington, Va., yesterday (Sept. 26), it was revealed that the "Aurora" supercompute Read more…

By Tiffany Trader

Google Releases Deeplearn.js to Further Democratize Machine Learning

August 17, 2017

Spreading the use of machine learning tools is one of the goals of Google’s PAIR (People + AI Research) initiative, which was introduced in early July. Last w Read more…

By John Russell

Graphcore Readies Launch of 16nm Colossus-IPU Chip

July 20, 2017

A second $30 million funding round for U.K. AI chip developer Graphcore sets up the company to go to market with its “intelligent processing unit” (IPU) in Read more…

By Tiffany Trader

GlobalFoundries Puts Wind in AMD’s Sails with 12nm FinFET

September 24, 2017

From its annual tech conference last week (Sept. 20), where GlobalFoundries welcomed more than 600 semiconductor professionals (reaching the Santa Clara venue Read more…

By Tiffany Trader

Leading Solution Providers

Amazon Debuts New AMD-based GPU Instances for Graphics Acceleration

September 12, 2017

Last week Amazon Web Services (AWS) streaming service, AppStream 2.0, introduced a new GPU instance called Graphics Design intended to accelerate graphics. The Read more…

By John Russell

Nvidia Responds to Google TPU Benchmarking

April 10, 2017

Nvidia highlights strengths of its newest GPU silicon in response to Google's report on the performance and energy advantages of its custom tensor processor. Read more…

By Tiffany Trader

EU Funds 20 Million Euro ARM+FPGA Exascale Project

September 7, 2017

At the Barcelona Supercomputer Centre on Wednesday (Sept. 6), 16 partners gathered to launch the EuroEXA project, which invests €20 million over three-and-a-half years into exascale-focused research and development. Led by the Horizon 2020 program, EuroEXA picks up the banner of a triad of partner projects — ExaNeSt, EcoScale and ExaNoDe — building on their work... Read more…

By Tiffany Trader

Cray Moves to Acquire the Seagate ClusterStor Line

July 28, 2017

This week Cray announced that it is picking up Seagate's ClusterStor HPC storage array business for an undisclosed sum. "In short we're effectively transitioning the bulk of the ClusterStor product line to Cray," said CEO Peter Ungaro. Read more…

By Tiffany Trader

Delays, Smoke, Records & Markets – A Candid Conversation with Cray CEO Peter Ungaro

October 5, 2017

Earlier this month, Tom Tabor, publisher of HPCwire and I had a very personal conversation with Cray CEO Peter Ungaro. Cray has been on something of a Cinderell Read more…

By Tiffany Trader & Tom Tabor

Intel Launches Software Tools to Ease FPGA Programming

September 5, 2017

Field Programmable Gate Arrays (FPGAs) have a reputation for being difficult to program, requiring expertise in specialty languages, like Verilog or VHDL. Easin Read more…

By Tiffany Trader

IBM Advances Web-based Quantum Programming

September 5, 2017

IBM Research is pairing its Jupyter-based Data Science Experience notebook environment with its cloud-based quantum computer, IBM Q, in hopes of encouraging a new class of entrepreneurial user to solve intractable problems that even exceed the capabilities of the best AI systems. Read more…

By Alex Woodie

Intel, NERSC and University Partners Launch New Big Data Center

August 17, 2017

A collaboration between the Department of Energy’s National Energy Research Scientific Computing Center (NERSC), Intel and five Intel Parallel Computing Cente Read more…

By Linda Barney

  • arrow
  • Click Here for More Headlines
  • arrow
Share This