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Suzuki, Kajita, and Super-Kamiokande awarded Breakthrough Prize in Fundamental Physics

2015/11/9

Dr. Yoichiro Suzuki, Dr. Takaaki Kajita, and the members of the Super-Kamiokande collaboration have been awarded the Breakthrough Prize in Fundamental Physics, for their role in the discovery and study of neutrino oscillation.

The prize, presented by the Breakthrough Prize Foundation, was awarded “for the fundamental discovery of neutrino oscillations, revealing a new frontier beyond, and possibly far beyond, the standard model of particle physics”. The prize is shared among five international experimental collaborations studying neutrino oscillations: Super-Kamiokande (Super-K), KEK-to-Kamioka/Tokai-to-Kamioka (K2K/T2K), Sudbury Neutrino Observatory (SNO), Kamioka Liquid-scintillator Anti-Neutrino Detector (KamLAND), and the Daya Bay Neutrino Experiment (Daya Bay). An award of 3M U.S. dollars is shared among them.

The award was presented at a ceremony at the NASA Ames Research Center in California held on Nov. 8. The ceremony was broadcast live in the U.S. on the National Geographic Channel, and was hosted by comedian Seth MacFarlane. A rebroadcast is scheduled for Fox on Nov. 29, at 7 p.m. ET. The Breakthrough Prizes honor advances in Mathematics, Fundamental Physics, and Life Sciences. The prize was established in 2012 by Yuri and Julia Milner, Sergey Brin and Anne Wojcicki, Jack Ma and Cathy Zhang, and Mark Zuckerberg and Priscilla Chan.

The Super-Kamiokande detector is comprised of 50,000 tons of water lined with 13,000 optical sensors, and is located 1,000 meters underground in the Kamioka mine in Japan. The Super-Kamiokande detector is used to study neutrinos from cosmic rays, the sun, supernovae, other astrophysical sources, and search for the decay of the proton. The Super-Kamiokande detector is also an integral part of the K2K and T2K long-baseline neutrino experiments that were also awarded the Breakthrough Prize, when it is used to detect neutrinos from an accelerator beam. The Super-Kamiokande collaboration announced the discovery of neutrino oscillations in 1998, based on the observation of neutrinos created by cosmic rays, so-called atmospheric neutrinos. They found that atmospheric muon neutrinos traveling great distances through the earth were disappearing, because they were changing into tau neutrinos. In 2001, the Super-Kamiokande collaboration published detailed studies of electron neutrinos produced by nuclear reactions in the sun, which revealed that the transformation of solar neutrinos was dictated by a fundamental parameter of nature. Dr. Kajita, now director of the Institute for Cosmic Ray Research, lead the atmospheric neutrino studies and Dr. Suzuki, later named spokesperson of the Super-Kamiokande collaboration, led the solar neutrino studies. The discovery of neutrino transformations led to the conclusion that neutrinos have mass and that the Standard Model of particle physics was incomplete. This opened the door for numerous follow-up experiments, including several that shared the Breakthrough Prize, as well as others proposed for the future.

Dr. Masayuki Nakahata from the University of Tokyo, Director of the Kamioka Neutrino Observatory and current spokesperson for the Super-Kamiokande collaboration said: “it is remarkable that the Kamioka site has hosted three of the five award winning experiments. Starting from the Kamiokande experiment led by Dr. Masatoshi Koshiba, our knowledge of neutrinos has been greatly expanded with those experiments during the last thirty years. ” Professor Henry Sobel from the University of California-Irvine (U.S. Co-Spokesperson of Super-Kamiokande) remarked, “what a wonderful surprise and culmination of many years of effort trying to unravel the mysteries of neutrinos. The recipients of the prize are most deserving and have been truly great colleagues”.

The Super-Kamiokande experiment was built and operated with funding from the Japanese Ministry of Education, Science, Sports and Culture, and the U.S. Department of Energy, Office of Science, and benefits from the cooperation of the Kamioka Mining and Smelting Company.

At the time of the discoveries, the Super-Kamiokande collaboration consisted of roughly 120 scientists from 27 institutions from Japan, United States, Poland, and South Korea:

[Additional Institutions]

The current collaboration has expanded and now includes additional institutes including international institutes from China, Spain, and Canada as

[Contact Persons]

Dr. Masayuki Nakahata
Director of the Kamioka Observatory
Institute of Cosmic Ray Research, University of Tokyo
nakahata@suketto.icrr.u-tokyo.ac.jp

Professor Henry Sobel
University of California Irvine
hsobel@uci.edu

 

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[Links]

►Breakthrough Prize

►Super-Kamiokande

►T2K experiment