On 3 January 1961 an explosion occurred in the Stationary Low Power Reactor Number One at the Atomic Energy Commission's National Reactor Testing Station in Idaho Falls, Idaho. The AEC revealed that three members of the reactor's maintenance crew were killed in the explosion and that an estimated "5 per cent of the gross fission product activity contained in the core . . . were released to the building environs." They concluded that the accident was caused by the manual withdrawal of the reactor's central control rod beyond specified limits during a maintenance operation.

Photographing Antimatter.

Experimenters from Yale University and from Brookhaven National Laboratory started a nearly two-year search for anti-xi-zero in September 1961. They used the Brookhaven alternating gradient synchrotron to hurl antiprotons at liquid hydrogen nuclei in a twenty-inch bubble chamber. For a brief period, the particles produced phenomenal energy and new particles that were tracked in the...