Arthur McDonald

Arthur B McDonald, recipient of the Canadian Medal, Ontario Medal, Nova Scotia Medal, member of the Royal Society of England, registered engineer, and member of the Royal Society of Canada, was born in Sydney, Nova Scotia, Canada. McDonald holds a bachelor's and master's degree in physics from Dalhousie University, a doctoral degree in physics from the California Institute of Technology, and 12 honorary degrees. From 1969 to 1982, served as a researcher at the Chuck River Nuclear Laboratory of Atomic Energy Canada Limited; From 1982 to 1989, served as a professor at Princeton University; From 1989 to 2013, he served as a professor at Queen's University of Kingston in Canada and became an honorary professor in 2013. Since 1989, he has been serving as the Director of the Sudbury Neutrino Observatory's SNO. McDonald has received numerous honors, including the Canadian Medal of Honor, the 2015 Nobel Prize in Physics, and the 2016 Breakthrough in Basic Physics Award in collaboration with SNO. Currently, he is still working in the underground laboratory of the Sudbury Neutrino Observatory, actively engaged in basic research related to neutrinos and dark matter. Arthur MacDonald was born on August 29, 1943 in Sydney, Nova Scotia, Canada. He is a Canadian physicist and was awarded the 2015 Nobel Prize in Physics for discovering neutrino oscillations, which indicate that neutrinos have mass. He was also awarded the award along with Japanese physicist Kajita Takaaki. McDonald graduated from Dalhousie University with a Bachelor's and Master's degrees in Physics in 1964 and 1965, respectively. In 1969, he obtained a doctoral degree in physics from the California Institute of Technology in Pasadena. In the same year, he returned to Canada and became a postdoctoral researcher at Chalk River Nuclear Laboratories, engaged in nuclear reaction research. In 1980, he became a senior researcher and left the laboratory in 1982 to become a professor at Princeton University. In the mid-1980s, McDonald participated in the establishment of the Sudbury Neutrino Observatory, a neutrino detector located 2100 meters deep in a nickel mine in Ontario, Canada, aimed at investigating neutrinos from Earth, the Sun, and even supernovae. In 1989, he became a professor at Queens University in Canada and became the first director of the Sudbury Neutrino Observatory's SNO. The construction of the observatory began in the 1990s, with its huge plastic spherical core filled with a special liquid called a liquid scintillator. When neutrinos interact with other particles in the detector, they generate light in the liquid scintillator and are captured by extremely sensitive photomultiplier tubes. The observatory must be built deep underground to avoid pollution caused by cosmic rays, which does not hinder the passage of neutrons through the 2100 meter rock layer. There are two proposed solutions to the solar neutrino problem. One is that nuclear reactions inside the sun do not produce neutrinos