Queen’s professor emeritus Arthur McDonald has been awarded the Nobel Prize for Physics for his discoveries regarding the changing identities of neutrinos. 

 

McDonald received the award — the highest honour for Physics awarded by the Royal Swedish Academy of Sciences — along with Japanese scientist Takaaki Kajita. 

 

Neutrinos are among the fundamental particles that make up the universe — the second most populous after light particles. So far, scientists have been unable to divide neutrinos into smaller particles.

 

McDonald and Kajita’s work has proved that these particles change from one type to another when in transit from the sun to the earth. 

 

McDonald’s research was conducted at the Sudbury Neutrino Observatory (SNO, or SNOLAB), where McDonald serves as Director. SNOLAB is a collaborative research facility located in an underground nickel mine. 

 

McDonald’s experiments demonstrated that neutrinos were present for the entire journey from the sun to the earth, and that their identities were different when captured at SNOLAB.

 

Kajita’s research, meanwhile, found that neutrinos from within the atmosphere altered between two identities on their way to a detector in Japan. 

 

In the announcement, the Royal Swedish Academy of the Sciences stated that the pair’s research has spurred “intense activity” on the subject, which is “expected to change our current understanding of the history, structure and future fate of the universe.” 

 

The Academy’s statement also noted that this discovery, which proves that neutrinos hold mass, has solved a mystery that physicists have grappled with for decades. The breakthrough challenges the Standard Model of particle physics, which previously did not take the mass of neutrinos into account. 

 

McDonald, who was born in Sydney, N.S. and completed degrees at Dalhousie University and the California Institute of Technology, has worked at Queen’s since 1989. 

 

During his time at Queen’s, McDonald has served as the inaugural Gordon and Patricia Gray Chair in Particle Astrophysics, and has been a professor emeritus since 2013. 

 

Dr. McDonald has received numerous other honours, including: 

• Officer of the Order of Canada

• Fellow of the Royal Society of the UK and Commonwealth

• Killam Prize in the Natural Sciences

• Henry Marshall Tory Medal from the Royal Society of Canada

• European Physics Society HEP Division Giuseppe and Vanna Cocconi Prize for Particle Astrophysics

 

McDonald and Kajita will be awarded a diploma and gold medal on Dec. 10, and will split a prize of approximately $960,000. 

 

In a statement on Tuesday, Principal Daniel Woolf said the prize reaffirmed the University’s status as a research-intensive institution, and congratulated McDonald for his “persistence, dedication and leadership”.