Doug Hallman (Neutrinos and the Sun: How the Sudbury Neutrino Observatory Solved the Solar Neutrino Problem), is a Professor of Physics and Chair of the Department of Physics & Astronomy at Laurentian University in Sudbury, Ontario. He is a founding member of the Sudbury Neutrino Observatory collaboration of scientists and serves as Director of Communications for SNO, and is the topic leader for the SNO research unit at Laurentian.

The idea of using Canada's unique stockpile of heavy water in an excellent site, deep underground at Inco's Creighton Mine near Sudbury to look at neutrinos from the Sun was developed into an international proposal for the Sudbury Neutrino Observatory (SNO) in the late 1980's and was funded in 1990. In April 2002, SNO scientists provided proof positive, from the analysis of more than two years of neutrino data, that neutrinos change from one species to another as they travel from the Sun, thus solving a 30- year puzzle of missing solar neutrinos. In the presentation, the construction and operation of SNO will be reviewed, and the SNO results and their astrophysical and particle physics implications will be described.