The American Physical Society has named Carl Richard Hagen, professor in the Department of Physics and Astronomy at the University of Rochester, as a recipient of the 2010 J. J. Sakurai Prize for Theoretical Particle Physics.

Hagen was honored with the prize, which is considered one of the most prestigious in physics, for his contributions that helped lead to the electroweak theory, and to what scientists believe is the origin of mass. He shares the prize with Robert Brout and Francois Englert of the Université Libre de Bruxelles, Gerald S. Guralnik of Brown University, Peter W. Higgs of the University of Edinburgh, and Tom W. B. Kibble of Imperial College, all of whom contributed to the same theory.

Hagen will accept the prize along with the other recipients at the American Physical Society's annual meeting, Feb. 14, in Washington, DC. The prize consists of $20,000, to be split among the six recipients, and a certificate citing the winners' contributions.

"Dick has played a pivotal role in the history of theoretical particle physics," says Nicholas Bigelow, chair of the Department of Physics and Astronomy. "We are proud of Dick both as a member of our faculty and as a scientist who influenced an entire field of physics with his insights."

Hagen is the second University of Rochester faculty member to win the Sakurai Prize. In 2004, Susumu Okubo, professor of physics, was honored for his groundbreaking investigations into the decay rates of subatomic particles.

In 1964, Hagen and the other winners of this year's prize wrote papers showing how a massless particle could acquire mass by means of a mechanism called symmetry breaking. Hagen and his colleagues suggested that the particles generated during symmetry breaking are created without mass, but that they acquire their masses because they interact with a field called the Higgs field, named after the co-recipient of the same name.

These papers helped physicists detect the particles that create the weak force, which is responsible for radioactivity. They also led to the 1979 Nobel Prize in physics for the unification of the weak force and the electromagnetic force.

The prize was endowed in 1984 as a memorial to and in recognition of the accomplishments of J. J. Sakurai by his family and friends.