Neutrino scientists win Nobel Prize for Physics

The Japan NewsTakaaki Kajita, 56, director of the University of Tokyo’s Institute for Cosmic Ray Research (ICRR), was awarded the Nobel Prize in Physics together with Arthur McDonald of Queen’s University, Canada, the Royal Swedish Academy of Sciences announced Tuesday.

And yet physicists were mystified as to why two-thirds of these particles, called neutrinos, seemed to be missing in action. Three years later, while working at the Sudbury Neutrino Observatory in Canada, McDonald found that neutrinos coming from the sun also switched identities.McDonald said that scientists would still like to know the actual masses of the various forms of neutrino. The change the particles undergo meant a whole new way of looking at particle physics: they had to have a few kind of mass. But it is now clear that the model does not provide a complete picture of how the fundamental constituents of the universe function.

The Sydney, N.S.-born physicist who has been awarded the 2015 Nobel Prize in Physics summed up his research work as “fun” in an interview four years ago with CBC Cape Breton. One way to solve the puzzle would be to find matter behaving differently from antimatter; flavor-changing neutrinos could be one way to see this difference. This change of identities by neutrinos requires that neutrinos have mass. McDonald, 72, is a professor emeritus at Queen’s University in Kingston, Canada.

It’s a matter of pride and excitement for Nova Scotians to learn that one of our own will share the 2015 Nobel Prize in physics for his work in revolutionizing our understanding of neutrinos, one of the fundamental – and most mysterious – particles that make up the universe. And ongoing experiments are delving into whether there are other types of neutrinos beyond the three clearly observed. After descending more than two kilometres in an active mine, researchers then have to trudge 1.5 kilometres to the laboratory because they need to be far away from the Earth’s surface to avoid cosmic rays that would mask their test results.

The Prize amount will be 8 million Swedish krona which will be shared equally between the laureates.

Although they are hard to detect, neutrinos are extremely common, second only to photons (particles of light) as the most abundant species in space.

1956: Two American scientists, Frederick Reines and Clyde Cowan, report the first hard evidence of the existence of neutrinos. Tens of thousands of them are passing right through your body right now, with no effect.

Intense activity is underway worldwide in order to understand more about the elusive particles.

“New discoveries about their deepest secrets are expected to change our current understanding of the history, structure and future fate of the universe”, the statement concludes.

Another student of Koshiba – University of Tokyo professor Yoji Totsuka, who died in 2008 – was central to the research that won Kajita the Nobel Prize.