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.
    • 2018-08-10 12:30:35
    • Article ID: 698832

    Protons Get Zippier in Neutron-Rich Nuclei

    Protons appear to get extra pep in their step when they're outnumbered by neutrons in the atom's nucleus.

    • Credit: DOE's Jefferson Lab

      The data for this result came from an experiment conducted with the Continuous Electron Beam Accelerator Facility at Jefferson Lab in Newport News, Va. This photo shows the CEBAF Large Acceptance Spectrometer in Jefferson Lab's Hall B, which was used to detect the particles.

    A new study carried out at the Department of Energy's Thomas Jefferson National Accelerator Facility has confirmed that increasing the number of neutrons as compared to protons in the atom’s nucleus also increases the average momentum of its protons. The nuclear physics result, which has implications for the dynamics of neutron stars, has been published in the journal Nature.

    The study involves short-range correlations, a phenomenon in which protons and neutrons, or nucleons, may pair up briefly inside the nucleus. This brief pairing imparts the two partners with high momentum.

    Earlier research found that nucleons prefer to pair up with nucleons of a different type (for instance, protons prefer neutrons and vice-versa). The research, which only measured protons, had also hinted that a greater fraction of protons than neutrons may pair up in neutron-rich nuclei, thus giving the protons a higher-average momentum than neutrons.

    “What differentiates this study from earlier ones is that this is the first time we detect the neutron,” says Meytal Duer, a graduate student at Tel Aviv University in Israel who is the lead author on the paper and who led the analysis effort. Including the neutron in the study, she says, also allowed the nuclear physics researchers to quantify the short-range correlations effect.

    Duer and her colleagues re-analyzed data from an experiment conducted in 2004. In the experiment, the Jefferson Lab Continuous Electron Beam Accelerator Facility produced a 5.01 GeV beam of electrons to probe nuclei of carbon, aluminum, iron and lead.

    “When the electron comes in and hits the nucleus, we have struck a proton or a neutron. We detected the scattered electron and the scattered proton or neutron,” Duer explains. “This is the first study to measure both protons and neutrons in short-range correlations and compare the high-momentum fraction carried by each.”

    The researchers found that when they compared the lightest nucleus, carbon, to the progressively heavier and neutron-rich nuclei of aluminum, iron and lead, the fraction of high-momentum protons went up.

    “When we’ve got 50 percent more neutrons in the nucleus, we’ve also got 50 percent more high-momentum protons than we had before,” says Or Hen, an assistant professor of physics at MIT and spokesperson for the data mining collaboration.

    Hen explains that this may be a consequence of the pair preference phenomenon exhibited by short-range correlations. That is, protons and neutrons both prefer to pair with particles different from themselves by 20 to 1. In neutron-rich nuclei, the few protons will have more pairing opportunities than the plentiful neutrons.

    “A main result of this paper is that as the nucleus becomes more and more neutron rich, the pairing probability of neutrons saturates, while the pairing probability of protons grows,” he says.

    Lawrence Weinstein, a lead coauthor and Professor & Eminent Scholar at Old Dominion University, says the result of that pairing preference has now been confirmed and quantified for the first time by this new finding.

    “As you add neutrons to the nucleus, the fraction of neutrons that are high momentum stays the same, but the fraction of protons at high momentum increases by 50 percent,” he says. “Put another way, it looks like when you add neutrons to a nucleus, it makes the protons move faster.”

    The result also has implications for the dynamics of neutron stars, which are made up of about five percent protons. Due to their high average momentum as compared to neutrons, the protons may have an out-sized effect on neutron star structure.

    The researchers say the next step is to move forward with new experiments that may be able to get at least ten times as much data on a wider range of nuclei, as well as continuing their efforts to scrutinize the data that’s already been collected for more insights into these mysterious nucleon pairings and how they influence nuclear structure.

    The analysis was carried out as part of the Jefferson Lab Hall B Data-Mining project, which is supported by DOE’s Office of Science. The research was also supported by the National Science Foundation, the Israel Science Foundation, the Chilean Comisión Nacional de Investigación Científica y Tecnológica, the French Centre National de la   Recherche Scientifique and Commissariat a l’Energie Atomique the French-American Cultural Exchange, the Italian Istituto Nazionale di Fisica Nucleare, the National Research Foundation of Korea, and the UK’s Science and Technology Facilities Council.

     

    -end-

    Jefferson Science Associates, LLC, a joint venture of the Southeastern Universities Research Association, Inc. and PAE, manages and operates the Thomas Jefferson National Accelerator Facility, or Jefferson Lab, for the U.S. Department of Energy's Office of Science.

    Jefferson Lab is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

    X
    X
    X
    • Filters

    • × Clear Filters
    Not Your Average Refinery

    Not Your Average Refinery

    PNNL researchers outline how to convert stranded biomass to sustainable fuel using electrochemical reduction reactions in mini-refineries powered by renewable energy.

    Supercooled Water Is a Stable Liquid, Scientists Show for the First Time

    Supercooled Water Is a Stable Liquid, Scientists Show for the First Time

    First-ever measurements provide evidence that supercooled liquid water exists in two distinct structures that co-exist and vary in proportion dependent on temperature

    New Calculation Refines Comparison of Matter with Antimatter

    New Calculation Refines Comparison of Matter with Antimatter

    An international collaboration of theoretical physicists has published a new calculation relevant to the search for an explanation of the predominance of matter over antimatter in our universe. The new calculation gives a more accurate prediction for the likelihood with which kaons decay into a pair of electrically charged pions vs. a pair of neutral pions.

    Digging into soil organic matter

    Digging into soil organic matter

    A new study found patterns in how soil organic matter forms across a wide range of climate types. Understanding how soils break down or preserve organic matter is important because organic matter plays a central role in the kind of services soils can provide, such as whether they make good agricultural soils or if they can sequester carbon to slow climate change.

    Quirky Response to Magnetism Presents Quantum Physics Mystery

    Quirky Response to Magnetism Presents Quantum Physics Mystery

    The search is on to discover new states of matter, and possibly new ways of encoding, manipulating, and transporting information. One goal is to harness materials' quantum properties for communications that go beyond what's possible with conventional electronics. Topological insulators--materials that act mostly as insulators but carry electric current across their surface--provide some tantalizing possibilities. Scientists at Brookhaven Lab describe one such material that should be right just right for making qubits. But this material doesn't obey the rules.

    High-precision electrochemistry: The new gold standard in fuel cell catalyst development

    High-precision electrochemistry: The new gold standard in fuel cell catalyst development

    As part of an international collaboration, scientists at Argonne National Laboratory have made a pivotal discovery that could extend the lifetime of fuel cells that power electric vehicles by eliminating the dissolution of platinum catalysts.

    Scientists probe the chemistry of a single battery electrode particle both inside and out

    Scientists probe the chemistry of a single battery electrode particle both inside and out

    Cracks and chemical reactions on a battery particle's surface can sap its ability to store and release energy. Scientists probed a single charged particle the size of a red blood cell to see how interior and surface damage influence each other.

    Quantum light squeezes the noise out of microscopy signals

    Quantum light squeezes the noise out of microscopy signals

    Researchers at Oak Ridge National Laboratory used quantum optics to advance state-of-the-art microscopy and illuminate a path to detecting material properties with greater sensitivity than is possible with traditional tools.

    Exploring Oxidative Pathways in Nuclear Fuel

    Exploring Oxidative Pathways in Nuclear Fuel

    An international team used PNNL microscopy to answer questions about how uranium dioxide--used in nuclear power plants--might behave in long-term storage.

    Researchers find unexpected electrical current that could stabilize fusion reactions

    Researchers find unexpected electrical current that could stabilize fusion reactions

    PPPL scientists have found that electrical currents can form in ways not known before. The novel findings could give researchers greater ability to bring the fusion energy that drives the sun and stars to Earth.


    • Filters

    • × Clear Filters
    Key Partners Mark Launch of Electron-Ion Collider Project

    Key Partners Mark Launch of Electron-Ion Collider Project

    U.S. Department of Energy (DOE) Undersecretary for Science Paul Dabbar, leaders from DOE's Brookhaven National Laboratory (Brookhaven Lab) and Thomas Jefferson National Accelerator Facility (Jefferson Lab), and elected officials from New York State and Virginia today commemorated the start of the Electron-Ion Collider project.

    Fermilab scientist Vladimir Shiltsev elected to Academia Europaea

    Fermilab scientist Vladimir Shiltsev elected to Academia Europaea

    Widely recognized for his work in accelerator beam physics, Shiltsev is one of 361 individuals elected to Academia Europaea, which promotes a wider appreciation of the value of European scholarship and research.

    PPPL physicist Hutch Neilson receives award for decades of leadership on national and international fusion experiments

    PPPL physicist Hutch Neilson receives award for decades of leadership on national and international fusion experiments

    Hutch Neilson, a physicist at PPPL who is head of ITER Projects, has received the 2020 Institute of Electrical and Electronics Engineers' (IEEE) Nuclear & Plasma Sciences Society (NPSS) Merit Award for decades of achievements, including collaborations with fusion experiments around the world from the Wendelstein 7-X (W7-X) stellarator in Germany to the international ITER experiment in the south of France.

    Virtual internships for physics students present challenges, build community

    Virtual internships for physics students present challenges, build community

    Summer is usually the time when student interns flock to PPPL to learn about fusion and plasma physics at a national laboratory. But because of the coronavirus pandemic, this year's students participated virtually from their homes around the country.

    Argonne cuts ribbon on expanded Materials Engineering Research Facility to enhance nation's future manufacturing competitiveness

    Argonne cuts ribbon on expanded Materials Engineering Research Facility to enhance nation's future manufacturing competitiveness

    Leaders from DOE and Argonne cut the ribbon on a new era of manufacturing -- science and technology that will accelerate commercialization of complex materials and chemicals critically important to U.S. competitiveness.

    DOE provides $21 million to advance diagnostics on the flagship fusion facility at PPPL

    DOE provides $21 million to advance diagnostics on the flagship fusion facility at PPPL

    New funding will upgrade key diagnostics on the National Spherical Tokamak Experiment-Upgrade, the flagship facility at PPPL.

    Lead Lab Selected for Next-Generation Cosmic Microwave Background Experiment

    Lead Lab Selected for Next-Generation Cosmic Microwave Background Experiment

    The largest collaborative undertaking yet to explore the relic light emitted by the infant universe has taken a step forward with the U.S. DOE's selection of Berkeley Lab to lead the partnership of national labs, universities, and other institutions that are joined in the effort to carry out the DOE roles and responsibilities.

    Jonathan Jarvis wins prestigious DOE award for development of next-generation particle beam cooling and control

    Jonathan Jarvis wins prestigious DOE award for development of next-generation particle beam cooling and control

    This award, totaling $2.5 million, will fund the development of a faster particle beam cooling method as well as the implementation of machine learning advancements to optimally control the system.

    Fermilab to lead $115 million National Quantum Information Science Research Center to build revolutionary quantum computer with Rigetti Computing, Northwestern University, Ames Laboratory, NASA, INFN and additional partners

    Fermilab to lead $115 million National Quantum Information Science Research Center to build revolutionary quantum computer with Rigetti Computing, Northwestern University, Ames Laboratory, NASA, INFN and additional partners

    Fermilab has been selected to lead one of five national centers to bring about transformational advances in quantum information science as a part of the U.S. National Quantum Initiative. The initiative provides the new Superconducting Quantum Materials and Systems Center -- based at Fermilab and comprising 20 partner institutions -- $115 million over five years with the goal of building and deploying a beyond-state-of-the-art quantum computer based on superconducting technologies. The center will also develop new quantum sensors, which could lead to the discovery of the nature of dark matter and other elusive subatomic particles.

    SLAC and Stanford join Q-NEXT national quantum center

    SLAC and Stanford join Q-NEXT national quantum center

    Q-NEXT will bring together nearly 100 world-class researchers from three national laboratories, 10 universities and 10 leading U.S. technology companies with the single goal of developing the science and technology to control and distribute quantum information. These activities, along with a focus on rapid commercialization of new technologies, will support the emerging "quantum economy" and ensure that the U.S. remains at the forefront in this rapidly advancing field.


    • Filters

    • × Clear Filters
    Harvesting Energy from Light using Bio-inspired Artificial Cells

    Harvesting Energy from Light using Bio-inspired Artificial Cells

    Scientists designed and connected two different artificial cells to each other to produce molecules called ATP (adenosine triphosphate).

    Engineering Living Scaffolds for Building Materials

    Engineering Living Scaffolds for Building Materials

    Bone and mollusk shells are composite systems that combine living cells and inorganic components. This allows them to regenerate and change structure while also being very strong and durable. Borrowing from this amazing complexity, researchers have been exploring a new class of materials called engineered living materials (ELMs).

    Excavating Quantum Information Buried in Noise

    Excavating Quantum Information Buried in Noise

    Researchers developed two new methods to assess and remove error in how scientists measure quantum systems. By reducing quantum "noise" - uncertainty inherent to quantum processes - these new methods improve accuracy and precision.

    How Electrons Move in a Catastrophe

    How Electrons Move in a Catastrophe

    Lanthanum strontium manganite (LSMO) is a widely applicable material, from magnetic tunnel junctions to solid oxide fuel cells. However, when it gets thin, its behavior changes for the worse. The reason why was not known. Now, using two theoretical methods, a team determined what happens.

    When Ions and Molecules Cluster

    When Ions and Molecules Cluster

    How an ion behaves when isolated within an analytical instrument can differ from how it behaves in the environment. Now, Xue-Bin Wang at Pacific Northwest National Laboratory devised a way to bring ions and molecules together in clusters to better discover their properties and predict their behavior.

    Tune in to Tetrahedral Superstructures

    Tune in to Tetrahedral Superstructures

    Shape affects how the particles fit together and, in turn, the resulting material. For the first time, a team observed the self-assembly of nanoparticles with tetrahedral shapes.

    Tracing Interstellar Dust Back to the Solar System's Formation

    Tracing Interstellar Dust Back to the Solar System's Formation

    This study is the first to confirm dust particles pre-dating the formation of our solar system. Further study of these materials will enable a deeper understanding of the processes that formed and have since altered them.

    Investigating Materials that Can Go the Distance in Fusion Reactors

    Investigating Materials that Can Go the Distance in Fusion Reactors

    Future fusion reactors will require materials that can withstand extreme operating conditions, including being bombarded by high-energy neutrons at high temperatures. Scientists recently irradiated titanium diboride (TiB2) in the High Flux Isotope Reactor (HFIR) to better understand the effects of fusion neutrons on performance.

    Better 3-D Imaging of Tumors in the Breast with Less Radiation

    Better 3-D Imaging of Tumors in the Breast with Less Radiation

    In breast cancer screening, an imaging technique based on nuclear medicine is currently being used as a successful secondary screening tool alongside mammography to improve the accuracy of the diagnosis. Now, a team is hoping to improve this imaging technique.

    Microbes are Metabolic Specialists

    Microbes are Metabolic Specialists

    Scientists can use genetic information to measure if microbes in the environment can perform specific ecological roles. Researchers recently analyzed the genomes of over 6,000 microbial species.


    Spotlight

    Virtual internships for physics students present challenges, build community
    Tuesday September 15, 2020, 04:35 PM

    Virtual internships for physics students present challenges, build community

    Princeton Plasma Physics Laboratory

    Blocking the COVID-19 Virus's Exit Strategy
    Monday August 31, 2020, 04:05 PM

    Blocking the COVID-19 Virus's Exit Strategy

    Brookhaven National Laboratory

    Summer Students Tackle COVID-19
    Monday August 31, 2020, 03:35 PM

    Summer Students Tackle COVID-19

    Brookhaven National Laboratory

    Graduate student at PPPL Ian Ochs wins top Princeton University fellowship
    Friday April 17, 2020, 05:25 PM

    Graduate student at PPPL Ian Ochs wins top Princeton University fellowship

    Princeton Plasma Physics Laboratory

    Barbara Garcia: A first-generation college student spends summer doing research at PPPL
    Tuesday September 24, 2019, 04:05 PM

    Barbara Garcia: A first-generation college student spends summer doing research at PPPL

    Princeton Plasma Physics Laboratory

    Argonne organization's scholarship fund blazes STEM pathway
    Tuesday September 17, 2019, 05:05 PM

    Argonne organization's scholarship fund blazes STEM pathway

    Argonne National Laboratory

    Brookhaven Lab, Suffolk Girl Scouts Launch Patch Program
    Friday September 13, 2019, 11:30 AM

    Brookhaven Lab, Suffolk Girl Scouts Launch Patch Program

    Brookhaven National Laboratory

    From an acoustic levitator to a
    Thursday September 12, 2019, 03:05 PM

    From an acoustic levitator to a "Neutron Bloodhound" robot, hands-on research inspires PPPL's summer interns

    Princeton Plasma Physics Laboratory

    Brookhaven Lab Celebrates the Bright Future of its 2019 Interns
    Friday August 30, 2019, 10:00 AM

    Brookhaven Lab Celebrates the Bright Future of its 2019 Interns

    Brookhaven National Laboratory

    PPPL apprenticeship program offers young people chance to earn while they learn high-tech careers
    Thursday August 01, 2019, 12:05 PM

    PPPL apprenticeship program offers young people chance to earn while they learn high-tech careers

    Princeton Plasma Physics Laboratory

    Creating a diverse pipeline
    Friday July 19, 2019, 01:05 PM

    Creating a diverse pipeline

    Princeton Plasma Physics Laboratory

    JSA Awards Graduate Fellowships for Research at Jefferson Lab
    Monday July 08, 2019, 03:00 PM

    JSA Awards Graduate Fellowships for Research at Jefferson Lab

    Thomas Jefferson National Accelerator Facility

    ILSAMP Symposium showcases benefits for diverse students, STEM pipeline
    Monday May 20, 2019, 12:05 PM

    ILSAMP Symposium showcases benefits for diverse students, STEM pipeline

    Argonne National Laboratory

    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





    Showing results

    0-4 Of 2215