Accessibility Statement Skip Navigation
  • Resources
  • Blog
  • Journalists
  • +44 (0)20 7454 5110
  • Client Login
  • Send a Release
Return to PR Newswire homepage
  • News
  • Products
  • Contact
When typing in this field, a list of search results will appear and be automatically updated as you type.

Searching for your content...

No results found. Please change your search terms and try again.
  • News in Focus
      • Browse News Releases

      • All Public Company News
      • All Multimedia News
      • View All News Releases

      • Regulatory News

      • D/A/CH Regulatory News
      • UK Regulatory News
      • View All Regulatory News

  • Business & Money
      • Auto & Transportation

      • Aerospace & Defense
      • Air Freight
      • Airlines & Aviation
      • Automotive
      • Maritime & Shipbuilding
      • Railroads & Intermodal Transportation
      • Supply Chain/Logistics
      • Transportation, Trucking & Railroad
      • Travel
      • Trucking & Road Transportation
      • View All Auto & Transportation

      • Business Technology

      • Blockchain
      • Broadcast Tech
      • Computer & Electronics
      • Computer Hardware
      • Computer Software
      • Data Analytics
      • Electronic Commerce
      • Electronic Components
      • Electronic Design Automation
      • Financial Technology
      • High Tech Security
      • Internet Technology
      • Nanotechnology
      • Networks
      • Peripherals
      • Semiconductors
      • View All Business Technology

      • Entertain­ment & Media

      • Advertising
      • Art
      • Books
      • Entertainment
      • Film & Motion Picture
      • Magazines
      • Music
      • Publishing & Information Services
      • Radio & Podcast
      • Television
      • View All Entertain­ment & Media

      • Financial Services & Investing

      • Accounting News & Issues
      • Acquisitions, Mergers & Takeovers
      • Banking & Financial Services
      • Bankruptcy
      • Bond & Stock Ratings
      • Conference Call Announcements
      • Contracts
      • Cryptocurrency
      • Dividends
      • Earnings
      • Earnings Forecasts & Projections
      • Financing Agreements
      • Insurance
      • Investments Opinions
      • Joint Ventures
      • Mutual Funds
      • Private Placement
      • Real Estate
      • Restructuring & Recapitalisation
      • Sales Reports
      • Shareholder Activism
      • Shareholder Meetings
      • Stock Offering
      • Stock Split
      • Venture Capital
      • View All Financial Services & Investing

      • General Business

      • Awards
      • Commercial Real Estate
      • Corporate Expansion
      • Earnings
      • Environmental, Social and Governance (ESG)
      • Human Resource & Workforce Management
      • Licensing
      • New Products & Services
      • Obituaries
      • Outsourcing Businesses
      • Overseas Real Estate (non-US)
      • Personnel Announcements
      • Real Estate Transactions
      • Residential Real Estate
      • Small Business Services
      • Socially Responsible Investing
      • Surveys, Polls & Research
      • Trade Show News
      • View All General Business

  • Science & Tech
      • Consumer Technology

      • Artificial Intelligence
      • Blockchain
      • Cloud Computing/Internet of Things
      • Computer Electronics
      • Computer Hardware
      • Computer Software
      • Consumer Electronics
      • Cryptocurrency
      • Data Analytics
      • Electronic Commerce
      • Electronic Gaming
      • Financial Technology
      • Mobile Entertainment
      • Multimedia & Internet
      • Peripherals
      • Social Media
      • STEM (Science, Tech, Engineering, Math)
      • Supply Chain/Logistics
      • Wireless Communications
      • View All Consumer Technology

      • Energy & Natural Resources

      • Alternative Energies
      • Chemical
      • Electrical Utilities
      • Gas
      • General Manufacturing
      • Mining
      • Mining & Metals
      • Oil & Energy
      • Oil & Gas Discoveries
      • Utilities
      • Water Utilities
      • View All Energy & Natural Resources

      • Environ­ment

      • Conservation & Recycling
      • Environmental Issues
      • Environmental Policy
      • Environmental Products & Services
      • Green Technology
      • Natural Disasters
      • View All Environ­ment

      • Heavy Industry & Manufacturing

      • Aerospace & Defence
      • Agriculture
      • Chemical
      • Construction & Building
      • General Manufacturing
      • HVAC (Heating, Ventilation & Air-Conditioning)
      • Machinery
      • Machine Tools, Metalworking & Metallurgy
      • Mining
      • Mining & Metals
      • Paper, Forest Products & Containers
      • Precious Metals
      • Textiles
      • Tobacco
      • View All Heavy Industry & Manufacturing

      • Telecomm­unications

      • Carriers & Services
      • Mobile Entertainment
      • Networks
      • Peripherals
      • Telecommunications Equipment
      • Telecommunications Industry
      • VoIP (Voice over Internet Protocol)
      • Wireless Communications
      • View All Telecomm­unications

  • Lifestyle & Health
      • Consumer Products & Retail

      • Animals & Pets
      • Beers, Wines & Spirits
      • Beverages
      • Bridal Services
      • Cannabis
      • Cosmetics & Personal Care
      • Fashion
      • Food & Beverages
      • Furniture & Furnishings
      • Home Improvement
      • Household, Consumer & Cosmetics
      • Household Products
      • Jewellery
      • Non-Alcoholic Beverages
      • Office Products
      • Organic Food
      • Product Recalls
      • Restaurants
      • Retail
      • Supermarkets
      • Toys
      • View All Consumer Products & Retail

      • Entertain­ment & Media

      • Advertising
      • Art
      • Books
      • Entertainment
      • Film & Motion Picture
      • Magazines
      • Music
      • Publishing & Information Services
      • Radio & Podcast
      • Television
      • View All Entertain­ment & Media

      • Health

      • Biometrics
      • Biotechnology
      • Clinical Trials & Medical Discoveries
      • Dentistry
      • FDA Approval
      • Fitness/Wellness
      • Health Care & Hospitals
      • Health Insurance
      • Infection Control
      • International Medical Approval
      • Medical Equipment
      • Medical Pharmaceuticals
      • Mental Health
      • Pharmaceuticals
      • Supplementary Medicine
      • View All Health

      • Sports

      • General Sports
      • Outdoors, Camping & Hiking
      • Sporting Events
      • Sports Equipment & Accessories
      • View All Sports

      • Travel

      • Amusement Parks & Tourist Attractions
      • Gambling & Casinos
      • Hotels & Resorts
      • Leisure & Tourism
      • Outdoors, Camping & Hiking
      • Passenger Aviation
      • Travel Industry
      • View All Travel

  • Policy & Public Interest
      • Policy & Public Interest

      • Animal Welfare
      • Corporate Social Responsibility
      • Economic News, Trends & Analysis
      • Education
      • Environmental
      • European Government
      • Labour & Union
      • Natural Disasters
      • Not For Profit
      • Public Safety
      • View All Policy & Public Interest

  • People & Culture
      • People & Culture

      • Aboriginal, First Nations & Native American
      • African American
      • Asian American
      • Children
      • Diversity, Equity & Inclusion
      • Hispanic
      • Lesbian, Gay & Bisexual
      • Men's Interest
      • People with Disabilities
      • Religion
      • Senior Citizens
      • Veterans
      • Women
      • View All People & Culture

  • Overview
  • Distribution
  • Paid Placement
  • Multichannel Amplification
  • Disclosure Services
  • SocialBoost
  • Rooms
    • MediaRoom
    • ESG Rooms
  • AI Tools
  • General Enquiries
  • Media Enquiries
  • Partnerships
  • Hamburger menu
  • Cision PR Newswire UK provides press release distribution, targeting, monitoring, and marketing services
  • Send a Release
    • Phone

    • +44 (0)20 7454 5110 from 8 AM - 5:30 PM GMT

    • ALL CONTACT INFO
    • Contact Us

      +44 (0)20 7454 5110
      from 8 AM - 5:30 PM GMT

  • Client Login
  • Send a Release
  • Resources
  • Blog
  • Journalists
  • News in Focus
    • Browse News Releases
    • Regulatory News
  • Business & Money
    • Auto & Transportation
    • Business Technology
    • Entertain­ment & Media
    • Financial Services & Investing
    • General Business
  • Science & Tech
    • Consumer Technology
    • Energy & Natural Resources
    • Environ­ment
    • Heavy Industry & Manufacturing
    • Telecomm­unications
  • Lifestyle & Health
    • Consumer Products & Retail
    • Entertain­ment & Media
    • Health
    • Sports
    • Travel
  • Policy & Public Interest
    • Policy & Public Interest
  • People & Culture
    • People & Culture
  • Client Login
  • Send a Release
  • Resources
  • Blog
  • Journalists
  • Overview
  • Distribution
  • Paid Placement
  • Multichannel Amplification
  • Disclosure Services
  • Cision Communications Cloud®
  • AI Tools
  • Client Login
  • Send a Release
  • Resources
  • Blog
  • Journalists
  • General Enquiries
  • Media Enquiries
  • Partnerships
  • Client Login
  • Send a Release
  • Resources
  • Blog
  • Journalists

First results from Fermilab's Muon g-2 experiment strengthen evidence of new physics

This image opens in the lightbox

News provided by

Fermilab

07 Apr, 2021, 14:59 GMT

Share this article

Share toX

Share this article

Share toX

The first results from the Muon g-2 experiment hosted at Fermi National Accelerator Laboratory show fundamental particles called muons behaving in a way not predicted by the Standard Model of particle physics. These results confirm an earlier experiment of the same name performed at Brookhaven National Laboratory. Combined, the two results show strong evidence that our best theoretical model of the subatomic world is incomplete. One potential explanation would be the existence of undiscovered particles or forces.

CHICAGO, April 7, 2021 /PRNewswire/ -- The long-awaited first results from the Muon g-2 experiment at the U.S. Department of Energy's Fermi National Accelerator Laboratory show fundamental particles called muons behaving in a way that is not predicted by scientists' best theory, the Standard Model of particle physics. This landmark result, made with unprecedented precision, confirms a discrepancy that has been gnawing at researchers for decades.

Continue Reading
This image opens in the lightbox
Muon g-2 experiment finds strong evidence for new physics
This image opens in the lightbox
The Muon g-2 ring sits in its detector hall amidst electronics racks, the muon beamline, and other equipment. This impressive experiment operates at negative 450 degrees Fahrenheit and studies the precession (or wobble) of muons as they travel through the magnetic field.
This image opens in the lightbox
The first result of the Muon g-2 experiment at Fermilab confirms the result from the experiment performed at Brookhaven National Lab two decades ago. Together, the two results show strong evidence that muons diverge from the Standard Model prediction.

The strong evidence that muons deviate from the Standard Model calculation might hint at exciting new physics. Muons act as a window into the subatomic world and could be interacting with yet undiscovered particles or forces.

"Today is an extraordinary day, long awaited not only by us but by the whole international physics community," said Graziano Venanzoni, co-spokesperson of the Muon g-2 experiment and physicist at the Italian National Institute for Nuclear Physics. "A large amount of credit goes to our young researchers who, with their talent, ideas and enthusiasm, have allowed us to achieve this incredible result."

A muon is about 200 times as massive as its cousin, the electron. Muons occur naturally when cosmic rays strike Earth's atmosphere, and particle accelerators at Fermilab can produce them in large numbers. Like electrons, muons act as if they have a tiny internal magnet. In a strong magnetic field, the direction of the muon's magnet precesses, or wobbles, much like the axis of a spinning top or gyroscope. The strength of the internal magnet determines the rate that the muon precesses in an external magnetic field and is described by a number that physicists call the g-factor. This number can be calculated with ultra-high precision.

As the muons circulate in the Muon g-2 magnet, they also interact with a quantum foam of subatomic particles popping in and out of existence. Interactions with these short-lived particles affect the value of the g-factor, causing the muons' precession to speed up or slow down very slightly. The Standard Model predicts this so-called anomalous magnetic moment extremely precisely. But if the quantum foam contains additional forces or particles not accounted for by the Standard Model, that would tweak the muon g-factor further.

"This quantity we measure reflects the interactions of the muon with everything else in the universe. But when the theorists calculate the same quantity, using all of the known forces and particles in the Standard Model, we don't get the same answer," said Renee Fatemi, a physicist at the University of Kentucky and the simulations manager for the Muon g-2 experiment. "This is strong evidence that the muon is sensitive to something that is not in our best theory."

The predecessor experiment at DOE's Brookhaven National Laboratory, which concluded in 2001, offered hints that the muon's behavior disagreed with the Standard Model. The new measurement from the Muon g-2 experiment at Fermilab strongly agrees with the value found at Brookhaven and diverges from theory with the most precise measurement to date. 

The accepted theoretical values for the muon are:
g-factor: 2.00233183620(86) [uncertainty in parentheses]
anomalous magnetic moment: 0.00116591810(43)

The new experimental world-average results announced by the Muon g-2 collaboration today are:
g-factor: 2.00233184122(82)
anomalous magnetic moment: 0.00116592061(41)

The combined results from Fermilab and Brookhaven show a difference with theory at a significance of 4.2 sigma, a little shy of the 5 sigma (or standard deviations) that scientists require to claim a discovery but still compelling evidence of new physics. The chance that the results are a statistical fluctuation is about 1 in 40,000.

The Fermilab experiment reuses the main component from the Brookhaven experiment, a 50-foot-diameter superconducting magnetic storage ring. In 2013, it was transported 3,200 miles by land and sea from Long Island to the Chicago suburbs, where scientists could take advantage of Fermilab's particle accelerator and produce the most intense beam of muons in the United States. Over the next four years, researchers assembled the experiment; tuned and calibrated an incredibly uniform magnetic field; developed new techniques, instrumentation, and simulations; and thoroughly tested the entire system.

The Muon g-2 experiment sends a beam of muons into the storage ring, where they circulate thousands of times at nearly the speed of light. Detectors lining the ring allow scientists to determine how fast the muons are precessing.

In its first year of operation, in 2018, the Fermilab experiment collected more data than all prior muon g-factor experiments combined. With more than 200 scientists from 35 institutions in seven countries, the Muon g-2 collaboration has now finished analyzing the motion of more than 8 billion muons from that first run.

"After the 20 years that have passed since the Brookhaven experiment ended, it is so gratifying to finally be resolving this mystery," said Fermilab scientist Chris Polly, who is a co-spokesperson for the current experiment and was a lead graduate student on the Brookhaven experiment.

Data analysis on the second and third runs of the experiment is under way, the fourth run is ongoing, and a fifth run is planned. Combining the results from all five runs will give scientists an even more precise measurement of the muon's wobble, revealing with greater certainty whether new physics is hiding within the quantum foam.

"So far we have analyzed less than 6% of the data that the experiment will eventually collect. Although these first results are telling us that there is an intriguing difference with the Standard Model, we will learn much more in the next couple of years," Polly said.

"Pinning down the subtle behavior of muons is a remarkable achievement that will guide the search for physics beyond the Standard Model for years to come," said Fermilab Deputy Director of Research Joe Lykken. "This is an exciting time for particle physics research, and Fermilab is at the forefront."

Fermilab is America's premier national laboratory for particle physics research. A U.S. Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC. Visit Fermilab's website at http://www.fnal.gov and follow us on Twitter @Fermilab.

The DOE 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, visit http://science.energy.gov.

Video - https://www.youtube.com/watch?v=ZjnK5exNhZ0

Photo - https://mma.prnewswire.com/media/1481216/Muon_g_2_magnet.jpg

Photo - https://mma.prnewswire.com/media/1481217/mg_2_results_FINAL_VIDEO.jpg

Photo - https://mma.prnewswire.com/media/1481215/FNAL_NAL_Blue_Logo.jpg 

Related Links

www.fnal.gov

Modal title

Contact PR Newswire

  • +44 (0)20 7454 5110
    from 8 AM - 5:30 PM GMT
  • General Enquiries
  • Media Enquiries
  • Partnerships

Products

  • Content Distribution
  • Multimedia Services
  • Disclosure Services
  • Cision Communications Cloud®

About

  • About PR Newswire
  • About Cision
  • Partnering Opportunities
  • Careers
  • Accessibility Statement
  • APAC
  • APAC - Simplified Chinese
  • APAC - Traditional Chinese
  • Brazil
  • Canada
  • Czech
  • Denmark
  • Finland
  • France
  • Germany
  • India
  • Indonesia
  • Israel
  • Japan
  • Korea
  • Mexico
  • Middle East
  • Middle East - Arabic
  • Netherlands
  • Norway
  • Poland
  • Portugal
  • Russia
  • Slovakia
  • Spain
  • Sweden
  • United States
  • Vietnam

My Services

  • All News Releases
  • Customer Portal
  • Resources
  • Blog
  • Journalists
  • Data Privacy

Do not sell or share my personal information:

  • Submit via Privacy@cision.com 
  • Call Privacy toll-free: 877-297-8921

Contact PR Newswire

Products

About

My Services
  • All News Releases
  • Customer Portal
  • Resources
  • Blog
  • Journalists
+44 (0)20 7454 5110
from 8 AM - 5:30 PM GMT
  • Terms of Use
  • Privacy Policy
  • Information Security Policy
  • Site Map
  • RSS
  • Cookie Settings
Copyright © 2025 PR Newswire Europe Limited. All Rights Reserved. A Cision company.