One month after Queen's University physicist Art McDonald won a Nobel Prize, the landmark neutrino experiment he headed up near Sudbury, Ont., has claimed a share of the world's most lucrative science award.
The Sudbury Neutrino Observatory (SNO) is one of five experiments named on Sunday as winners of the 2016 Breakthrough Prize in fundamental physics. Dr. McDonald and his team will will split the $3-million prize with three experiments in Japan and one located in China. All the experiments are being recognized for results that collectively shed light on neutrinos, fleeting particles that are produced in nuclear reactions and that can easily pass through solid matter, making them extremely difficult to detect.
"It's a big day for our whole community," said Hirohisa Tanaka, a professor of physics at the University of Toronto and the head of a 40-strong group of Canadians who are international participants in T2K, one of the three Japan-based experiments.
Dr. Tanaka said he and his colleagues were pleased to learn that the five experiments are being awarded the prize together, since they all contributed to an emerging and sometimes bizarre portrait of how neutrinos behave.
Neutrinos are known to come in three varieties, each one a type of fundamental particle with its own specific set of characteristics. Yet, in different ways and under different conditions, the prize-winning experiments first demonstrated and then studied how neutrinos can switch identities from one type to another.
For example, in 2011 Dr. Tanaka and his colleagues on the T2K experiment reported that they had directly measured one way in which such a switch can occur, by using a beam of neutrinos created at a Japanese particle accelerator that was fired through solid rock at a giant neutrino detector 295 kilometres away.
Several years earlier, Dr. McDonald and his team built the SNO experiment, housed more than 2 kilometres below ground in working a nickel mine, to pick up neutrinos streaming from the sun's core. Using the data collected by SNO in the late 1990s and early 2000s, they showed that solar neutrinos, which are all created as one type, arrive at Earth as a mixture of types.
The cavern that housed SNO has since expanded and morphed into a multipurpose underground physics facility called SNOLab.
SNOLab's director, Nigel Smith, said the Breakthrough Prize coming so soon after Dr. McDonald's Nobel win is a further validation of the calbre of science the Sudbury facility can deliver.
"The hope is this will again highlight the kind of capability that Canada has and the worthwhile investment we are making," he said.
Ray Jayawardhana, dean of science at York University and author of the popular science book Neutrino Hunters said the double recognition is the culmination of a decades-long journey for neutrino research from a scientific backwater to the cutting edge of discovery in particle physics.
"It's been a long time coming, but neutrinos are finally getting the attention they deserve, given the starring role these shadowy particles play in a great many sagas across physics, cosmology and astronomy," he said.
Established in 2012 by Russian entrepreneur Yuri Milner, the Breakthrough prize has rapidly gained profile because of the size of its purse and the support and involvement of Silicon Valley luminaries such as Google co-founder Sergey Brin and Facebook CEO Mark Zuckerberg.