DOE News
    Doe Science news source
    The DOE Science News Source is a Newswise initiative to promote research news from the Office of Science of the DOE to the public and news media.
    • 2019-03-07 11:00:10
    • Article ID: 709262

    ORNL-led collaboration solves a beta-decay puzzle with advanced nuclear models

    • Credit: Andy Sproles/ORNL

      First principles calculations showed that strong correlations and interactions between two nucleons slow down beta-decays in atomic nuclei compared to what’s expected from the beta decay of free neutrons. This impacts the synthesis of heavy elements and the search for neutrino-less double-beta decay.

    OAK RIDGE, Tenn., March 11, 2019—An international collaboration including scientists at the Department of Energy’s (DOE’s) Oak Ridge National Laboratory (ORNL) solved a 50-year-old puzzle that explains why beta decays of atomic nuclei are slower than what is expected based on the beta decays of free neutrons.

    The findings, published in Nature Physics, fill a long-standing gap in physicists’ understanding of beta decay, an important process stars use to create heavier elements, and emphasize the need to include subtle effects—or more realistic physics—when predicting certain nuclear processes.

    “For decades, scientists have lacked a first-principles understanding of nuclear beta decay, in which protons convert into neutrons, or vice versa, to form other elements,” said ORNL staff scientist Gaute Hagen, who led the study. “Our team demonstrated that theoretical models and computation have progressed to the point where it is possible to calculate some decay properties with enough precision to allow for direct comparison to experiment.”

    To solve the problem, the team simulated tin-100 decaying into indium-100, a neighboring element on the periodic table. The two elements share the same number of nucleons (protons and neutrons), with tin-100 possessing 50 protons to indium-100’s 49.

    Calculating beta decay precisely required the team to not only accurately simulate the structure of the mother and daughter nuclei but also account for the correlated interactions between two nucleons during the transition. This additional treatment presented an extreme computational challenge due to the combination of strong nuclear correlations and interactions involving the decaying nucleon.

    In the past, nuclear physicists worked around this problem by inserting a fundamental constant to reconcile observed beta-decay rates of neutrons inside and outside the nucleus, a practice known as “quenching.” But with machines like ORNL’s Titan supercomputer, Hagen’s team demonstrated that this mathematical crutch is no longer necessary.

    “Nobody really understood why this quenching factor worked. It just did,” said ORNL computational scientist Gustav Jansen. “We found that it could largely be explained by including two nucleons in the decay—for example, two protons decaying into a proton and a neutron, or a proton and a neutron decaying into two neutrons.”

    The team, which included partners from Lawrence Livermore National Laboratory, University of Tennessee, University of Washington, TRIUMF (Canada), and Technical University Darmstadt (Germany), performed a comprehensive study of beta decays from light to medium-heavy nuclei up to tin-100.

    The achievement gives nuclear physicists increased confidence as they search for answers to some of the most perplexing mysteries related to the formation of matter in the universe. Beyond regular beta decay, scientists are looking to compute neutrinoless double beta decay, a theorized form of nuclear decay that, if observed, would explore important new physics and help to determine the mass of the neutrino.

    Tin to In

    Many elements have isotopes that decay over long periods of time. For example, the half-life of carbon-14, the nucleus used in carbon dating, is 5,730 years. Other nuclei, however, exist only for fractions of a second before ejecting particles in an attempt to stabilize.

    In neutron beta decay, an electron and an anti-neutrino are emitted. When tin-100 transforms into indium-100, the nucleus undergoes beta-plus decay, expelling a positron and a neutrino when converting a proton to a neutron.

    With its equal number of protons and neutrons, tin-100 exhibits an unusually high rate of beta decay, giving the ORNL team a strong signal from which to verify its results. Furthermore, the tin-100 nucleus is “doubly magic,” meaning the nucleons fill out defined shells inside the nucleus that make it strongly bound and relatively simple in structure. The ORNL team’s NUCCOR code, which is programmed to solve the nuclear many-body problem, excels at describing doubly magic nuclei up and down the nuclear chart.

    “A doubly magic nucleus like tin-100 isn’t as complicated as many other nuclei,” said Thomas Papenbrock, a researcher at the University of Tennessee and ORNL. “This means we can reliably compute it using our coupled cluster method, which calculates properties of large nuclei by accounting for forces between the individual nucleons.”

    To model beta decay, however, the team also had to calculate the structure of indium-100, a more complex nucleus than the doubly magic tin-100. This required a more precise treatment of the strong correlations between the nucleons. By borrowing ideas from quantum chemistry, which treats electrons as waves, Hagen’s team successfully developed techniques to model these processes.

    “In our case we are dealing with nucleons instead of electrons, but the quantum chemistry concepts have helped us branch out from doubly magic nuclei and expand into these open-shell regions,” said ORNL physicist Titus Morris.

    Guiding experiment

    Now that Hagen’s team has shown its understanding of beta decay is on par with experiment, it’s looking to take advantage of new supercomputers like ORNL’s Summit, the world’s most powerful, to guide current and future experiments.

    Researchers are currently using Summit to simulate how calcium-48, another doubly magic nucleus, would undergo neutrinoless double beta decay—a process in which two neutrons beta decay into protons, but without emitting any neutrinos. The results could aid experimentalists in the selection of an optimal detector material for the potential discovery of this rare phenomenon.

    “Currently, calculations using different nuclear models of neutrinoless double beta decay may differ by as much as a factor of six,” Hagen said. “Our goal is to provide a benchmark for other models and theories.”

    This research was supported by the DOE Office of Science.

    UT-Battelle LLC manages ORNL for DOE’s Office of Science. The Office of Science is 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 https://science.energy.gov/.

     

    • other-fb
    • other-tw
    X
    X
    X
    • Filters

    • × Clear Filters
    In a first, researchers identify reddish coloring in an ancient fossil - a 3-million-year-old mouse

    In a first, researchers identify reddish coloring in an ancient fossil - a 3-million-year-old mouse

    Researchers have for the first time detected chemical traces of red pigment in an ancient fossil - an exceptionally well-preserved mouse, not unlike today's field mice, that roamed the fields of what is now the German village of Willershausen around 3 million years ago.

    Improving Isotope Supply for a Cancer-Fighting Drug

    Improving Isotope Supply for a Cancer-Fighting Drug

    Production of actinium-227 ramps up for use in a drug to fight prostate cancer that has spread to bone.

    Extracting Signs of the Elusive Neutrino

    Extracting Signs of the Elusive Neutrino

    Scientists use software to "develop" images that trace neutrinos' interactions in a bath of cold liquid argon.

    Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth to rapidly predict behavior of plasma that fuels fusion reactions

    Machine learning speeds modeling of experiments aimed at capturing fusion energy on Earth to rapidly predict behavior of plasma that fuels fusion reactions

    Release describes application of machine learning form of artificial intelligence to predict the behavior of fusion plasma.

    Record-shattering underwater sound

    Record-shattering underwater sound

    A team of researchers has produced a record-shattering underwater sound with an intensity that eclipses that of a rocket launch. The intensity was equivalent to directing the electrical power of an entire city onto a single square meter, resulting in sound pressures above 270 decibels.

    CosmoGAN: Training a Neural Network to Study Dark Matter

    CosmoGAN: Training a Neural Network to Study Dark Matter

    A Berkeley Lab-led research group is using a deep learning method known as generative adversarial networks to enhance the use of gravitational lensing in the study of dark matter.

    Breakthrough Technique for Studying Gene Expression Takes Root in Plants

    Breakthrough Technique for Studying Gene Expression Takes Root in Plants

    An open-source RNA analysis platform has been successfully used on plant cells for the first time - an advance that could herald a new era of fundamental research and bolster efforts to engineer more efficient food and biofuel crop plants. The technology, called Drop-seq, is a method for measuring the RNA present in individual cells, allowing scientists to see what genes are being expressed and how this relates to the specific functions of different cell types.

    Bio-inspired material targets oceans' uranium stores for sustainable nuclear energy

    Bio-inspired material targets oceans' uranium stores for sustainable nuclear energy

    Scientists have demonstrated a new bio-inspired material for an eco-friendly and cost-effective approach to recovering uranium from seawater. The low-cost polymer adsorbent could help push past bottlenecks in the cost and efficiency of extracting uranium resources from oceans for sustainable energy production.

    Study Concludes Glassy Menagerie of Particles in Beach Sands Near Hiroshima is Fallout Debris from A-Bomb Blast

    Study Concludes Glassy Menagerie of Particles in Beach Sands Near Hiroshima is Fallout Debris from A-Bomb Blast

    A years-long study that involved scientists and experiments at Berkeley Lab and UC Berkeley concluded that an odd assortment of particles found in beach sands in Japan are most likely fallout debris from the 1945 Hiroshima A-bomb blast.

    New technique merging sound and math could help prevent plasma disruptions in fusion facilities

    New technique merging sound and math could help prevent plasma disruptions in fusion facilities

    Scientists have created a novel method for measuring the stability of plasma in fusion facilities called "tokamaks." Involving an innovative use of a mathematical tool, the method might lead to a technique for stabilizing plasma and making fusion reactions more efficient.


    • Filters

    • × Clear Filters
    Cryogenics equipment maker licenses ORNL auto-fill method for more efficient liquid helium use

    Cryogenics equipment maker licenses ORNL auto-fill method for more efficient liquid helium use

    Advanced Research Systems has licensed an ORNL technology designed to automatically refill liquid helium used in laboratory equipment for low-temperature scientific experiments, which will reduce downtime, recover more helium and increase overall efficiency.

    New Argonne coating could have big implications for lithium batteries

    New Argonne coating could have big implications for lithium batteries

    In a new discovery, scientists at the U.S. Department of Energy's (DOE) Argonne National Laboratory have developed a new cathode coating by using an oxidative chemical vapor deposition technique. The new coating can keep the battery's cathode electrically and ionically conductive and ensures that the battery stays safe after many cycles.

    Argonne's Chain Reaction Innovations appoints first advisory council

    Argonne's Chain Reaction Innovations appoints first advisory council

    World-class energy leaders will offer their expertise to Chain Reaction Innovations (CRI), the entrepreneurship program at the U.S. Department of Energy's Argonne National Laboratory, as part of a new Advisory Council announced today. CRI has named 14 Advisory Council members, including investors, industry experts and business executives, to help guide its growth and strategy.

    ORNL, Lincoln Electric to Advance Large-Scale Metal Additive Manufacturing Technology

    ORNL, Lincoln Electric to Advance Large-Scale Metal Additive Manufacturing Technology

    The new agreement builds upon ORNL and Lincoln Electric's previous developments by extending additive technology to new materials, leveraging data analytics and enabling rapid manufacture of metal components in excess of 100 pounds per hour.

    Students from Minnesota and Massachusetts Win DOE's 29th National Science Bowl(r)

    Students from Wayzata High School in Plymouth, Minnesota, won the 2019 U.S. Department of Energy (DOE) National Science Bowl(r) (NSB) today in Washington, D.C. In the middle school competition, students from Jonas Clarke Middle School in Lexington, Massachusetts, took home first place.

    Five new innovators join Chain Reaction Innovations in third cohort

    Five new innovators join Chain Reaction Innovations in third cohort

    Five new innovators will be joining Chain Reaction Innovations (CRI), the entrepreneurship program at the U.S. Department of Energy's (DOE's) Argonne National Laboratory, as part of the elite program's third cohort. Announced on Monday, April 22, these innovators were selected following an extensive national solicitation process and two-part pitch competition, with reviews from industry experts, investors, scientists and engineers.

    Department of Energy Announces $20 Million for Artificial Intelligence Research

    Today, the U.S. Department of Energy (DOE) announced a total of $20 million in funding for innovative research and development in artificial intelligence (A.I.) and machine learning.

    Tim Knewitz named Argonne National Laboratory's Chief Financial Officer

    Tim Knewitz named Argonne National Laboratory's Chief Financial Officer

    The U.S. Department of Energy's Argonne National Laboratory has named Tim Knewitz at its Chief Financial Officer.

    Department of Energy Announces $95 Million for Small Business Research and Development Grants

    U.S. Energy Secretary Rick Perry today announced that the Department of Energy will award 86 grants totaling $95 million to 74 small businesses in 21 states.

    DOE's Science Graduate Student Research Program Selects 70 Students to Pursue Research at DOE Laboratories

    The Department of Energy's (DOE's) Office of Science has selected 70 graduate students from across the nation for its 2018 Solicitation 2 cycle for Office of Science Graduate Student Research (SCGSR) Program.


    • Filters

    • × Clear Filters
    Improving Isotope Supply for a Cancer-Fighting Drug

    Improving Isotope Supply for a Cancer-Fighting Drug

    Production of actinium-227 ramps up for use in a drug to fight prostate cancer that has spread to bone.

    Extracting Signs of the Elusive Neutrino

    Extracting Signs of the Elusive Neutrino

    Scientists use software to "develop" images that trace neutrinos' interactions in a bath of cold liquid argon.

    Slow Charge Generation Plays Big Role in Model Material for Solar Cells

    Slow Charge Generation Plays Big Role in Model Material for Solar Cells

    Insight about energy flow in copper-based material could aid in creating efficient molecular electronics.

    Capturing Energy Flow in a Plasma by Measuring Scattered Light

    Capturing Energy Flow in a Plasma by Measuring Scattered Light

    First measurements of heat flux in plasmas experientially sheds light on models relying on classical thermal transport.

    Artificial Intelligence and Deep Learning Accelerate Efforts to Develop Clean, Virtually Limitless Fusion Energy

    Artificial Intelligence and Deep Learning Accelerate Efforts to Develop Clean, Virtually Limitless Fusion Energy

    The Fusion Recurrent Neural Network reliably forecasts disruptive and destructive events in tokamaks.

    Spin Flipper Upends Protons

    Spin Flipper Upends Protons

    The spin direction of protons was reversed, for the first time, using a nine-magnet device, potentially helping tease out details about protons that affect medical imaging and more.

    Splitting Water Fast! Catalyst Works Faster than Mother Nature

    Splitting Water Fast! Catalyst Works Faster than Mother Nature

    Design principles lead to a catalyst that splits water in a low pH environment, vital for generating solar fuels.

    Sea Quark Spin Surprise!

    Sea Quark Spin Surprise!

    Antiquark spin contribution to proton spin depends on flavor, which could help unlock secrets about the nuclear structure of atoms that make up nearly all visible matter in our universe.

    The Weak Side of the Proton

    The Weak Side of the Proton

    A precision measurement of the proton's weak charge narrows the search for new physics.

    Fast-Moving Pairs May Solve 35-Year-Old Mystery

    Fast-Moving Pairs May Solve 35-Year-Old Mystery

    Physicists develop a universal mathematical description that suggests that proton-neutron pairs in a nucleus may explain why their associated quarks have lower average momenta than predicted.


    Spotlight

    Integrating Scientific Computing into Science Curricula
    Monday May 13, 2019, 11:05 AM

    Integrating Scientific Computing into Science Curricula

    Brookhaven National Laboratory

    Students from Minnesota and Massachusetts Win DOE's 29th National Science Bowl(r)
    Monday April 29, 2019, 02:05 PM

    Students from Minnesota and Massachusetts Win DOE's 29th National Science Bowl(r)

    Department of Energy, Office of Science

    DOE's Science Graduate Student Research Program Selects 70 Students to Pursue Research at DOE Laboratories
    Friday April 12, 2019, 03:05 PM

    DOE's Science Graduate Student Research Program Selects 70 Students to Pursue Research at DOE Laboratories

    Department of Energy, Office of Science

    Young Women's Conference in STEM seeks to change the statistics one girl at a time
    Thursday March 28, 2019, 03:05 PM

    Young Women's Conference in STEM seeks to change the statistics one girl at a time

    Princeton Plasma Physics Laboratory

    Students team with Argonne scientists and engineers to learn about STEM careers
    Tuesday March 12, 2019, 05:05 PM

    Students team with Argonne scientists and engineers to learn about STEM careers

    Argonne National Laboratory

    Lynbrook High wins 2019 SLAC Regional Science Bowl competition
    Wednesday February 13, 2019, 02:05 PM

    Lynbrook High wins 2019 SLAC Regional Science Bowl competition

    SLAC National Accelerator Laboratory

    Equipping the next generation for a technological revolution
    Thursday January 24, 2019, 01:05 PM

    Equipping the next generation for a technological revolution

    Argonne National Laboratory

    Chemistry intern inspired by Argonne's real-world science
    Friday January 18, 2019, 05:05 PM

    Chemistry intern inspired by Argonne's real-world science

    Argonne National Laboratory

    Chasing a supernova
    Friday January 18, 2019, 04:05 PM

    Chasing a supernova

    Argonne National Laboratory

    Argonne intern streamlines the beamline
    Tuesday January 08, 2019, 02:05 PM

    Argonne intern streamlines the beamline

    Argonne National Laboratory

    Research on Light-Matter Interaction Could Lead to Improved Electronic and Optoelectronic Devices
    Thursday October 11, 2018, 04:00 PM

    Research on Light-Matter Interaction Could Lead to Improved Electronic and Optoelectronic Devices

    Rensselaer Polytechnic Institute (RPI)

    Innovating Our Energy Future
    Wednesday October 03, 2018, 07:05 PM

    Innovating Our Energy Future

    Oregon State University, College of Engineering

    Physics graduate student takes her thesis research to a Department of Energy national lab
    Tuesday October 02, 2018, 03:05 PM

    Physics graduate student takes her thesis research to a Department of Energy national lab

    University of Alabama at Birmingham

    Friday September 21, 2018, 01:05 PM

    "Model" students enjoy Argonne campus life

    Argonne National Laboratory

    Writing Code for a More Skilled and Diverse STEM Workforce
    Thursday September 06, 2018, 01:05 PM

    Writing Code for a More Skilled and Diverse STEM Workforce

    Brookhaven National Laboratory

    New graduate student summer school launches at Princeton Plasma Physics Laboratory
    Tuesday September 04, 2018, 11:30 AM

    New graduate student summer school launches at Princeton Plasma Physics Laboratory

    Princeton Plasma Physics Laboratory

    The Gridlock State
    Friday August 31, 2018, 06:05 PM

    The Gridlock State

    California State University (CSU) Chancellor's Office

    Meet Jasmine Hatcher and Trishelle Copeland-Johnson
    Friday August 31, 2018, 02:05 PM

    Meet Jasmine Hatcher and Trishelle Copeland-Johnson

    Brookhaven National Laboratory

    Argonne hosts Modeling, Experimentation and Validation Summer School
    Friday August 24, 2018, 11:05 AM

    Argonne hosts Modeling, Experimentation and Validation Summer School

    Argonne National Laboratory

    Students affected by Hurricane Maria bring their research to SLAC
    Wednesday August 22, 2018, 01:05 PM

    Students affected by Hurricane Maria bring their research to SLAC

    SLAC National Accelerator Laboratory

    Brookhaven Lab Pays Tribute to 2018 Summer Interns
    Wednesday August 22, 2018, 10:05 AM

    Brookhaven Lab Pays Tribute to 2018 Summer Interns

    Brookhaven National Laboratory

    Changing How Buildings Are Made
    Monday August 20, 2018, 12:05 PM

    Changing How Buildings Are Made

    Washington University in St. Louis

    CSUMB Selected to Host Architecture at Zero Competition in 2019
    Thursday August 16, 2018, 12:05 PM

    CSUMB Selected to Host Architecture at Zero Competition in 2019

    California State University, Monterey Bay

    Department of Energy Invests $64 Million in Advanced Nuclear Technology
    Friday July 20, 2018, 03:00 PM

    Department of Energy Invests $64 Million in Advanced Nuclear Technology

    Rensselaer Polytechnic Institute (RPI)

    Professor Miao Yu Named the Priti and Mukesh Chatter '82 Career Development Professor
    Thursday July 19, 2018, 05:00 PM

    Professor Miao Yu Named the Priti and Mukesh Chatter '82 Career Development Professor

    Rensselaer Polytechnic Institute (RPI)

    2018 RHIC & AGS Annual Users' Meeting: 'Illuminating the QCD Landscape'
    Tuesday July 03, 2018, 11:05 AM

    2018 RHIC & AGS Annual Users' Meeting: 'Illuminating the QCD Landscape'

    Brookhaven National Laboratory

    Argonne welcomes <em>The Martian</em> author Andy Weir
    Friday June 29, 2018, 06:05 PM

    Argonne welcomes The Martian author Andy Weir

    Argonne National Laboratory

    Creating STEM Knowledge and Innovations to Solve Global Issues Like Water, Food, and Energy
    Monday June 18, 2018, 09:55 AM

    Creating STEM Knowledge and Innovations to Solve Global Issues Like Water, Food, and Energy

    Illinois Mathematics and Science Academy (IMSA)

    Professor Emily Liu Receives $1.8 Million DoE Award for Solar Power Systems Research
    Friday June 15, 2018, 10:00 AM

    Professor Emily Liu Receives $1.8 Million DoE Award for Solar Power Systems Research

    Rensselaer Polytechnic Institute (RPI)

    Celebrating 40 years of empowerment in science
    Thursday June 07, 2018, 03:05 PM

    Celebrating 40 years of empowerment in science

    Argonne National Laboratory

    Introducing Graduate Students Across the Globe to Photon Science
    Monday May 07, 2018, 10:30 AM

    Introducing Graduate Students Across the Globe to Photon Science

    Brookhaven National Laboratory

    Students from Massachusetts and Washington Win DOE's 28th National Science Bowl(r)
    Wednesday May 02, 2018, 04:05 PM

    Students from Massachusetts and Washington Win DOE's 28th National Science Bowl(r)

    Department of Energy, Office of Science

    The Race for Young Scientific Minds
    Thursday April 12, 2018, 07:05 PM

    The Race for Young Scientific Minds

    Argonne National Laboratory

    Q&A: Al Ashley Reflects on His Efforts to Diversify SLAC and Beyond
    Wednesday March 14, 2018, 02:05 PM

    Q&A: Al Ashley Reflects on His Efforts to Diversify SLAC and Beyond

    SLAC National Accelerator Laboratory

    Insights on Innovation in Energy, Humanitarian Aid Highlight UVA Darden's Net Impact Week
    Thursday February 15, 2018, 12:05 PM

    Insights on Innovation in Energy, Humanitarian Aid Highlight UVA Darden's Net Impact Week

    University of Virginia Darden School of Business

    Ivy League Graduate, Writer and Activist with Dyslexia Visits CSUCI to Reframe the Concept of Learning Disabilities
    Friday February 09, 2018, 11:05 AM

    Ivy League Graduate, Writer and Activist with Dyslexia Visits CSUCI to Reframe the Concept of Learning Disabilities

    California State University, Channel Islands

    Photographer Adam Nadel Selected as Fermilab's New Artist-in-Residence for 2018
    Wednesday January 17, 2018, 12:05 PM

    Photographer Adam Nadel Selected as Fermilab's New Artist-in-Residence for 2018

    Fermi National Accelerator Laboratory (Fermilab)

    Fermilab Computing Partners with Argonne, Local Schools for Hour of Code
    Wednesday January 17, 2018, 12:05 PM

    Fermilab Computing Partners with Argonne, Local Schools for Hour of Code

    Fermi National Accelerator Laboratory (Fermilab)

    Q&A: Sam Webb Teaches X-Ray Science from a Remote Classroom
    Wednesday December 20, 2017, 01:05 PM

    Q&A: Sam Webb Teaches X-Ray Science from a Remote Classroom

    SLAC National Accelerator Laboratory

    The Future of Today's Electric Power Systems
    Monday December 18, 2017, 01:05 PM

    The Future of Today's Electric Power Systems

    Rensselaer Polytechnic Institute (RPI)

    Supporting the Development of Offshore Wind Power Plants
    Monday December 18, 2017, 12:05 PM

    Supporting the Development of Offshore Wind Power Plants

    Rensselaer Polytechnic Institute (RPI)

    Stairway to Science
    Tuesday October 03, 2017, 01:05 PM

    Stairway to Science

    Argonne National Laboratory

    After-School Energy Rush
    Thursday September 28, 2017, 12:05 PM

    After-School Energy Rush

    Argonne National Laboratory

    Bringing Diversity Into Computational Science Through Student Outreach
    Thursday September 28, 2017, 10:05 AM

    Bringing Diversity Into Computational Science Through Student Outreach

    Brookhaven National Laboratory

    From Science to Finance: SLAC Summer Interns Forge New Paths in STEM
    Thursday September 21, 2017, 03:05 PM

    From Science to Finance: SLAC Summer Interns Forge New Paths in STEM

    SLAC National Accelerator Laboratory

    Students Discuss 'Cosmic Opportunities' at 45th Annual SLAC Summer Institute
    Thursday September 07, 2017, 02:05 PM

    Students Discuss 'Cosmic Opportunities' at 45th Annual SLAC Summer Institute

    SLAC National Accelerator Laboratory





    Showing results

    0-4 Of 2215