New Atom Particle Discovered

The discovery last month of a new atomic particle called the antiproton was made by a team of radiation laboratory physicists, which included Dr. OwenChamberlain '41, of the University of California. Hailed by scientists as a finding which might inaugurate a new era of nuclear research, the discovery was announced jointly by the University of California and the Atomic Energy Commission.

In theory the existence of antiprotons has been accepted for some 25 years, but until experiments were conducted in the Berkeley Bevatron, most powerful atomsmasher in the world, these atomic particles, which occur only at high energy, could not be produced and detected. The antiproton is a heavy particle of the opposite electric charge, but of the same mass, as the proton, which is found in all atomic nuclei. The Berkeley scientists as quoted in The New York Times said that the antiproton does not exist in the atomic nucleus, which is composed of protons and neutrons, but comes into being after a proton of great power, such as that generated in the Bevatron, hits a neutron, creating a new proton and an antiproton. In the collision, a part of the bombarding proton energy is converted into mass, according to Einstein's theory. While the antiproton is stable in a vacuum, it is short lived, as it disintegrates upon coming into contact with the proton.

The discovery of the antiproton reinforces the concept of electrical charge symmetry in nature; that is, for each known charged particle there is a particle of equal mass with opposite charge. This is considered a fundamental step for further discoveries in nuclear research.

While an undergraduate, Owen Chamberlain was elected to Phi Beta Kappa and awarded a Cramer Fellowship to study at the University of California. From 1943. until 1946 he was a research assistant on the atomic project at Los Alamos and later studied under a fellowship, sponsored by the Institute for Nuclear Studies, at the University of Chicago, where he received the Ph.D. degree in 1949. He has been an instructor in physics at the University of California since 1948.