Emilio Segre; UC Berkeley Physicist, Nobel Laureate
Emilio G. Segre, a Nobel Prize-winning scientist who helped confirm the existence of an atomic particle that ended the search for “a nuclear ghost which has haunted the world’s physicists for a generation,” suffered a fatal heart attack Saturday. He was 84.
Segre, a world-renowned physicist and faculty member at UC Berkeley for nearly five decades, was walking near his home in Lafayette, Calif., when he collapsed and died, UC Berkeley spokesman Ray Colvig said.
Born Feb. 1, 1905, in Tivoli, Italy, Segre entered the annals of scientific history while still in his native homeland, where he discovered technetium--the first artificially produced element to be isolated by man.
Antiproton Discovery
But it was at a UC Berkeley laboratory, two decades after Segre and his wife fled Italy and the anti-Jewish wartime decrees of Benito Mussolini, that the scientist made perhaps his most significant discovery.
Segre proved the existence of the antiproton--a negatively charged proton that destroys itself as well as the matter it strikes. The antiproton’s existence “had been predicted for a long time,” Colvig said, but was not proven until 1955, when Segre and fellow Berkeley physics professor Owen Chamberlain detected the elusive particle.
With the help of a specially designed maze through which only antiprotons could pass and a machine that accelerated protons and other atomic particles to a high energy level, Segre and Chamberlain validated long-held but unproven scientific beliefs with the discovery of 60 antiprotons.
Four years later, he and Chamberlain received the Nobel Prize for Physics. The prize was a redeeming triumph for Segre, who was once barred from working on certain research because he was a foreigner.
Segre lived a life full of contrasts. The son of an industrialist, he became the first student to earn a doctoral degree in physics under famed scientist and professor Enrico Fermi at the University of Rome. Segre then served as director of the University of Palermo’s physics laboratory from 1936 to 1938.
Fled Italy
But when Mussolini unleashed his racist wartime decrees, Segre and his first wife, who were Jewish, fled Italy and settled in the United States. He began to work at UC Berkeley but was barred from working on some classified research because, as an Italian citizen, he was officially an “enemy alien.”
Ironically, Segre went on to do wartime work at Los Alamos Laboratory, where he helped discover plutonium-239 and the fact that plutonium could be split by slow neutrons--an important step in development of the plutonium bomb.
Segre never worked on weapons research again after the war, Colvig said, and in later years he was a strong proponent of reducing nuclear weapons. In 1983, he, Chamberlain and three other Nobel laureates were among the 70 scientists who, while gathered at Los Alamos National Laboratory for a 40th anniversary celebration, signed a petition calling for worldwide reduction of such arms.
It was not an unusual step for the world lecturer and author, who could sometimes be as gruff as he was charming. “He was always a man of conscience,” Colvig said.
Segre is survived by his second wife, Rosa Mines, three children and five grandchildren. Plans for a memorial service are pending, and the family has suggested that gifts in Segre’s memory be given to the Save the Redwoods League.
