Skip to main content

PNNL

  • About
  • News & Media
  • Careers
  • Events
  • Research
    • Scientific Discovery
      • Biology
        • Human Health
        • Integrative Omics
        • Microbiome Science
      • Chemistry
        • Catalysis
        • Chemical Physics
      • Computational Research
        • Artificial Intelligence
        • Computational Mathematics & Statistics
        • Graph and Data Analytics
        • High-Performance Computing
        • Software Engineering
        • Visual Analytics
      • Earth System Science
        • Plant Science
        • Atmospheric Science
        • Terrestrial Aquatics
        • Subsurface Science
        • Ecosystem Science
        • Coastal Science
      • Materials Science
        • Solid Phase Processing
        • Science of Interfaces
        • Precision Materials by Design
        • Materials in Extreme Environments
      • Nuclear & Particle Physics
        • Dark Matter
        • Neutrino Physics
        • Flavor Physics
        • Fusion Energy Science
      • Quantum Information Science
    • Energy Resiliency
      • Electric Grid Modernization
        • Distribution
        • Transmission
        • Grid Architecture
        • Grid Analytics
          • AGM Program
        • Grid Cybersecurity
        • Emergency Response
      • Energy Efficiency
        • Building Technologies
          • Building-Grid Integration
          • Advanced Lighting
        • Residential Buildings
          • Energy Efficient Technology Integration
          • Home Energy Score
          • Building America Solution Center
        • Commercial Buildings
        • Federal Buildings
          • Federal Performance Optimization
          • Resilience and Security
        • Building Energy Codes
        • Appliance and Equipment Standards
      • Energy Storage
        • Grid Energy Storage
        • Vehicle Energy Storage
      • Environmental Management
        • Environmental Remediation
        • Waste Processing
        • Radiation Measurement
      • Fossil Energy
        • Subsurface Energy Systems
        • Advanced Hydrocarbon Conversion
      • Nuclear Energy
        • Reactor Licensing
        • Reactor Operations
        • Fuel Cycle Research
        • Advanced Reactors
      • Renewable Energy
        • Hydropower
          • Environmental Performance of Hydropower
          • Hydropower and the Electric Grid
          • Hydropower Cybersecurity and Digitalization
          • Materials Science for Hydropower
          • Water + Hydropower Planning
        • Marine Energy
          • Environmental Monitoring for Marine Energy
          • Marine Biofouling and Corrosion
          • Marine Energy Resource Characterization
          • Testing for Marine Energy
          • The Blue Economy
        • Wind Energy
          • Distributed Wind
          • Offshore Wind
          • Uncertainty Quantification
          • Wildlife and Wind
          • Wind Data Archive and Portal
          • Wind Resource Characterization
        • Geothermal Energy
        • Solar Energy
      • Transportation
        • Vehicle Technologies
          • Emission Control
          • Energy-Efficient Mobility Systems
          • Lightweight Materials
          • Vehicle Electrification
        • Bioenergy Technologies
          • Algal Biofuels
          • Aviation Biofuels
          • Waste-to-Energy and Products
        • Hydrogen & Fuel Cells
    • National Security
      • Computing & Analytics
        • Artificial Intelligence
        • Computational Mathematics & Statistics
        • Graph and Data Analytics
        • High-Performance Computing
        • Software Engineering
        • Visual Analytics
      • Cybersecurity
        • Discovery and Insight
        • Proactive Defense
        • Trusted Systems
      • Nuclear Nonproliferation
        • Stakeholder Engagement
        • Technical Training
      • Weapons of Mass Effect
        • Explosives Detection
        • Chemical & Biological Signatures Science
        • Radiological & Nuclear Detection
    • Lab Objectives
    • Publications & Reports
    • S&T Capabilities
  • People
    • Inventors
    • Diversity
    • Lab Leadership
    • Lab Fellows
    • Staff Accomplishments
  • Partner with PNNL
    • Academia
      • Distinguished Graduate Research Programs
      • Internships
      • Visiting Faculty Program
      • Joint Appointments
      • Joint Institutes
    • Community
      • STEM Education
      • Philanthropy
      • Volunteering
      • Economic Impact
    • Industry
      • Industry Partnerships
      • Licensing & Technology Transfer
      • Entrepreneurial Leave
  • Facilities & Centers
    • All Facilities
      • Atmospheric Radiation Measurement User Facility
      • Bioproducts, Sciences, and Engineering Lab
      • Environmental Molecular Sciences Laboratory
      • Institute for Integrated Catalysis
      • Marine and Coastal Research Laboratory
      • Radiochemical Processing Laboratory
      • Shallow Underground Laboratory
      • Systems Engineering Building
      • Wasteform Development Laboratory
      • PNNL Seattle Research Center
      • PNNL 5G Innovation Studio

Breadcrumb

  1. Research
  2. Scientific Discovery
  3. Nuclear & Particle Physics
  4. Neutrino Physics

Neutrino
Physics

Probing tiny, mysterious
particles to answer
the big questions

  • Biology
  • Chemistry
  • Computational Research
  • Earth System Science
  • Materials Science
  • Nuclear & Particle Physics
    • Dark Matter
    • Neutrino Physics
    • Flavor Physics
    • Fusion Energy Science
  • Quantum Information Science
  • News & Updates

How did we come to live in a universe full of matter? The laws of physics as we currently understand them would predict complete annihilation with antimatter just after the Big Bang. That we are here to ask such a question is proof that our understanding is not yet complete. Ironically, the key to this mystery likely involves the tiniest of things—a subatomic particle called the neutrino. 

Neutrino physics research at PNNL is supported by the U.S. Department of Energy, Office of Science, Nuclear Physics program which supports experimental and theoretical efforts to learn how visible matter came into being and evolved, how it organizes itself, and how it interacts. This fundamental research provides solid foundations for many other areas of science. The more we learn about neutrinos, the better we understand matter and the universe. The quest to learn such things often leads to technologies and applications that cannot be foreseen.

Currently, some basic neutrino properties, such as their absolute mass, and even their intrinsic particle nature are unknown. Even if individual neutrinos are extremely light, they are so abundant that they might collectively account for a significant amount of all the mass of normal matter in the universe. Furthermore, if they are the right kind of particle, they might have played a critical role in tipping our universe in favor of matter over antimatter. These properties are crucial for understanding the history of the universe. At PNNL, researchers work with international collaborations of scientists and engineers to address the unknown mass and particle nature of neutrinos through some of the world’s leading particle physics experiments.

Finding missing energy

The neutrino’s mass can be revealed through a small amount of “missing” energy in the decay of tritium, a radioactive form of hydrogen. The energy of the electrons emitted in those decays can be very precisely determined by observing their motions in a magnetic trap. Any missing energy must have been carried away as the mass of the unobserved neutrino, also emitted in the decay. 

The Project 8 collaboration was the first to measure individual electrons like this; the information about electron motion is carried by a signal with just a quadrillionth of a watt of power. Project 8 is currently working to grow its prototype demonstrations into the next generation of neutrino mass experiment.

The particle nature of the neutrino can be determined by observing an extremely rare type of radioactive decay: neutrinoless double beta decay. The “MAJORANA” Demonstrator Project, is searching for evidence using PNNL technology that produced the most radiopure copper in the world, thereby reducing background signals from natural radiation in the detector materials. PNNL scientists and engineers are now working toward the next generation of experiments to increase sensitivity to a quadrillion times the age of the universe by exposing tons of material for several years. In particular, they are working with an international team to create the next Enriched Xenon Observatory (nEXO) consisting of several tons of liquid xenon, enriched in the rare isotope xenon-136.

Related Capabilities

Nuclear Engineering
Applied Mathematics
Computational Science

Related Links

DOE Nuclear Physics

PNNL

  • Get in Touch
    • Contact
    • Careers
    • Doing Business
    • Environmental Reports
    • Security & Privacy
  • Research
    • Scientific Discovery
    • Energy Resiliency
    • National Security
Subscribe to PNNL News
Department of Energy Logo Battelle Logo
Pacific Northwest National Laboratory (PNNL) is managed and operated by Battelle for the Department of Energy
  • YouTube
  • Facebook
  • Twitter
  • Instagram
  • LinkedIn