Arthur B. McDonald and Oscillating Neutrinos
'Queen's University professor emeritus Arthur McDonald is the co-winner of the 2015 Nobel Prize in physics. … Dr. McDonald won the award, along with Takaaki Kajita of the University of Tokyo, "for their key contributions to the experiments which demonstrated that neutrinos change identities."…
The findings solved a puzzle that physicists had wrestled with for decades … .
Dr. McDonald's research took place at the Sudbury Neutrino Observatory (SNO) scientific collaboration, an advanced facility located 2 km underground in an active nickel mine. The experiment demonstrated that neutrinos from the sun were not disappearing on their way to earth and were captured with a different identity when arriving at SNO.
Meanwhile, Dr. Kajita presented the discovery that neutrinos from the atmosphere switch between two identities on their way to the Super-Kamiokande detector in Japan.
This "metamorphosis" requires that neutrinos have mass.'1
'For particle physics this was a historic discovery. Its Standard Model of the innermost workings of matter had been incredibly successful, having resisted all experimental challenges for more than twenty years. However, as it requires neutrinos to be massless, the new observations had clearly showed that the Standard Model cannot be the complete theory of the fundamental constituents of the universe.'2
'The discovery changed "our understanding of the innermost workings of matter and can prove crucial to our view of the universe," the Nobel committee said.
Dr. McDonald arrived at Queen's in 1989 ... and served as the director of [Sudbury Neutrino Observatory] SNO, now known as SNOLAB. ... [He] has been a professor emeritus since 2013.'1
The U.S. Department of Energy, though its Office of Science, has provided support for the SNO (including facilities and some research). This support was instrumental in developing and sustaining the facilities that helped enable the discovery of neutrino oscillation.
McDonald 'graduated from Dalhousie University in Halifax, Nova Scotia in 1964 with a B.Sc. (Hon. Physics) and 1965 with a M.Sc. (Physics). He continued his studies at California Institute of Technology [Caltech] in Pasadena, graduating in 1969 with a Ph. D. in Nuclear Physics. From 1969 until 1981 he worked at the Chalk River Nuclear Laboratories of Atomic Energy of Canada, performing fundamental nuclear and particle physics experiments with accelerators and reactors. In 1981 he accepted a Professorship in the Physics Department at Princeton University, Princeton, N.J. and continued his research program there as Co-Principal Investigator of the Princeton Cyclotron.' 3
2 Edited excerpts from Metamorphosis in the Particle World, Nobel Prize Press Release, October 6, 2015
3 Edited excerpts from Keynote Speakers - Dr. Arthur McDonald
Additional information about Arthur McDonald and his neutrino research is available in full-text documents and on the Web.
Parity Nonconservation in Proton-water Scattering at 800 MeV; DOE Technical Report ; 1982
Parity Nonconservation in Proton-Proton and Proton-Water Scattering at 1. 5 GeV/c; DOE Technical Report ; 1984
Parity Violation in Proton-Proton Scattering at Intermediate Energies; DOE Technical Report ; 1986
Neutrino Observations from the Sudbury Neutrino Observatory; DOE Technical Report ; 2001
Measurement of the Cosmic Ray and Neutrino-Induced Muon Flux at the Sudbury Neutrino Observatory; DOE Technical Report ; 2009
Additional Web Pages:
Neutrino 'Flip' Wins Physics Nobel Prize, BBC News