BOOM

Trending Searches

    SUPPORT
    BOOM

    Trending News

      • Fact Check 
        • Fast Check
        • Politics
        • Business
        • Entertainment
        • Social
        • Sports
        • World
      • Law
      • Explainers
      • News 
        • All News
      • Decode 
        • Impact
        • Scamcheck
        • Life
        • Voices
      • Media Buddhi 
        • Digital Buddhi
        • Senior Citizens
        • Videos
      • Web Stories
      • BOOM Research
      • BOOM Labs
      • Deepfake Tracker
      • Videos 
        • Facts Neeti
      • Home-icon
        Home
      • About Us-icon
        About Us
      • Authors-icon
        Authors
      • Team-icon
        Team
      • Careers-icon
        Careers
      • Internship-icon
        Internship
      • Contact Us-icon
        Contact Us
      • Methodology-icon
        Methodology
      • Correction Policy-icon
        Correction Policy
      • Non-Partnership Policy-icon
        Non-Partnership Policy
      • Cookie Policy-icon
        Cookie Policy
      • Grievance Redressal-icon
        Grievance Redressal
      • Republishing Guidelines-icon
        Republishing Guidelines
      • Fact Check-icon
        Fact Check
        Fast Check
        Politics
        Business
        Entertainment
        Social
        Sports
        World
      • Law-icon
        Law
      • Explainers-icon
        Explainers
      • News-icon
        News
        All News
      • Decode-icon
        Decode
        Impact
        Scamcheck
        Life
        Voices
      • Media Buddhi-icon
        Media Buddhi
        Digital Buddhi
        Senior Citizens
        Videos
      • Web Stories-icon
        Web Stories
      • BOOM Research-icon
        BOOM Research
      • BOOM Labs-icon
        BOOM Labs
      • Deepfake Tracker-icon
        Deepfake Tracker
      • Videos-icon
        Videos
        Facts Neeti
      Trending Tags
      TRENDING
      • #Operation Sindoor
      • #Pahalgam Terror Attack
      • #Narendra Modi
      • #Rahul Gandhi
      • #Waqf Amendment Bill
      • #Arvind Kejriwal
      • #Deepfake
      • #Artificial Intelligence
      • Home
      • World
      • Physics Duo Wins The Nobel Prize...
      World

      Physics Duo Wins The Nobel Prize For Solving Longstanding Neutrino Puzzle

      By - Ryan Wilkinson |
      Published -  7 Oct 2015 3:22 PM IST
    • Boomlive

      Canada’s Arthur B McDonald and Japan’s Takaaki Kajita have won this year’s Nobel Prize in Physics for their surprising discovery that tiny, subatomic particles called neutrinos have mass.

      Their experimental results forced scientists to rethink the “Standard Model” of particle physics that had successfully explained all observations of the subatomic world for decades.

      What are neutrinos?

      Neutrinos are produced when radioactive isotopes decay and have been shrouded in mystery ever since Wolfgang Pauli first proposed them in 1930. In the Standard Model, they were assumed to have no mass (like particles of light, photons) and be neutral (lacking electric charge). This would also explain why neutrinos usually pass straight through matter without interacting, making them extremely difficult to detect. Enormous instruments are required to observe them in sufficient numbers to study their properties.

      Neutrinos were first directly observed by the Cowan-Reines experimentin 1956, using neutrinos from a nuclear reactor and two large tanks of water. If a neutrino interacted with a nucleus in the detector, this would result in a flash of light that could be picked up by photomultiplier tubes that were sandwiched between the tanks. Frederick Reines was awarded the Nobel Prize in 1995 for this work.

      Where the neutrino fits in the subatomic family. MissMJ - Own work by uploader, PBS NOVA, Fermilab, Office of Science, United States Department of Energy, Particle Data Group, CC BY

      However, when detectors became sensitive enough to observe neutrinos created in nuclear reactions in the Sun, scientists faced a big problem. They had calculated the amount of neutrinos from the Sun that should be hitting the Earth, but observed only a third of this number in their experiments. A further Nobel Prize was presented to Ray Davis in 2002for this discovery. The mystery of these missing neutrinos was coined the “solar neutrino problem” and remained a puzzle for forty years, until the collaborations led by Kajita and McDonald made their exciting discovery.

      Underground discovery

      There are three different types, or “flavour”, of neutrino – electron, muon and tau – which have slightly different mass and can interact with other particles in different ways.

      In 1998, Kajita, who now works at the University of Tokyo, announced that the Super-Kamiokande experiment in Japan had found that neutrinos “oscillate” between these flavours, which is possible thanks to the strange rules of quantum mechanics.

      Super-Kamiokande detected muon-neutrinos coming straight from the atmosphere above, as well as those hitting the detector from below after having travelled through the Earth. Since neutrinos barely interact, there should be equal numbers of neutrinos coming from the two directions. However, the muon-neutrinos that came straight down to Super-Kamiokande were more numerous than those that had passed through the planet. This indicated that muon-neutrinos that travelled longer had more time to oscillate into tau-neutrinos that could evade the detectors.

      The Royal Swedish Academy of Sciences as they announced the prize. Reuters
      These results were confirmed in 2001 by Arthur B McDonald, based at Queen’s University in Canada, and the Sudbury National Observatorycollaboration, this time by detecting oscillations of neutrinos from the Sun. By carefully observing the interactions of neutrinos with “heavy water”, they were able to determine the total number of neutrinos, as well as the fraction of electron-neutrinos. They crucially showed that there were no missing neutrinos, once all the flavours had been taken into account.

      The discovery of Kajita and McDonald solved the solar neutrino problem as it could explain where the missing neutrinos had gone; they simply changed flavour on their way from the Sun to the detector, meaning that they couldn’t be recorded. It also showed that the Standard Model was incomplete, as such oscillations are impossible in the absence of neutrino masses.

      From their pioneering work, the neutrino field has boomed across the world, with experiments in every continent. Now that we know neutrinos have mass, we need new theories to explain how they acquire it. If new fundamental particles are responsible for neutrino masses, one of them could account for dark matter, a mysterious substance that makes up the vast majority of the matter in the Universe. Work is ongoing in this area and exciting discoveries may be just around the corner.

      Tags

      AstrophysicsNeutrinoNobel LaureateNobel PrizeNobel Prize 2015Particle physics
      Read Full Article
      Next Story
      Our website is made possible by displaying online advertisements to our visitors.
      Please consider supporting us by disabling your ad blocker. Please reload after ad blocker is disabled.
      X

      Subscribe to BOOM Newsletters

      👉 No spam, no paywall — but verified insights.

      Please enter a Email Address
      Subscribe for free!

      Stay Ahead of Misinformation!

      Please enter a Email Address
      Subscribe Now🛡️ 100% Privacy Protected | No Spam, Just Facts
      By subscribing, you agree with the Terms & conditions and Privacy Policy connected to the offer

      Thank you for subscribing!

      You’re now part of the BOOM community.

      Or, Subscribe to receive latest news via email
      Subscribed Successfully...
      Copy HTMLHTML is copied!
      There's no data to copy!