Arthur McDonald, a native of Sydney and a Dalhousie University graduate, is a co-winner of this year’s Nobel Prize in physics.
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In 1998, working at the Super-Kamiokande detector – a 50,000-tonne tank of highly purified water built at the bottom of an old zinc mine in central Japan – Kajita discovered that neutrinos seemed to change identities on their way from the sun to Earth. 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.
Kajita and McDonald, using different experiments, managed to explain this around the turn of the millennium by showing that neutrinos actually changed identities, or “flavors”, and therefore must have a few mass, however small.
They have no electrical charge (the name means “little neutral one”) and even among subatomic particles they are mere wisps – with nearly no mass at all. Most that reach Earth were created by nuclear reactions inside the Sunday. “The discovery that neutrinos have mass has profound consequences, not only for particle physics, pointing at physics beyond the Standard Model, but also for astrophysics and cosmology”, says Botner, who is the spokesperson for the IceCube neutrino experiment at the South Pole.
Kajita and McDonald will receive the prize at a ceremony in Stockholm on December 10, sharing the prize money of 8 million Swedish kroner (about $960,000). It takes a lot of people and a long time.
McDonald of Queen’s University in Canada and Takaaki Kajita of the University of Tokyo were awarded Nobel Prize for making a groundbreaking discovery in physics. “But if they would be transformed to muon-neutrinos or tau-neutrinos on their way to Earth, that would make the deficit of the captured electron-neutrinos understandable”.
1956: Two American scientists, Frederick Reines and Clyde Cowan, report the first hard evidence of the existence of neutrinos.
The Nobel Prize for Physics has previously been awarded to scientists for things like the study of the Higgs Boson particle and for complicated work that deals with graphene.
Neutrinos very rarely interact with matter; they can zip through a block of lead a light-year across.
The Nobel Prizes in chemistry, literature and peace will be announced later this week. On the rare occasion that a neutrino strikes an atom’s nucleus, the collision produces a dim streak of light that contains information about its energy and the direction it’s traveling.
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Yesterday, the academy announced the winners of the Nobel Prize in Physiology or Medicine, William C. Campbell, Satoshi Omura and Youyou Tu for their “discoveries concerning a novel therapy against infections caused by roundworm parasites”, which are responsible for the illnesses elephantiasis, river blindness and malaria.
