The Demon Core's Second Victim May 21, 1946. Los Alamos. Louis Slotin held two metal half-spheres around a plutonium ball. A screwdriver kept them apart. The screwdriver slipped. Blue light flashed. He pulled the spheres apart with bare hands. He saved seven coworkers. He died nine days later. Same core that killed Daghlian.
Source
Los Alamos National Laboratory historical report LA-13638, 'A Review of Criticality Accidents,' 2000 revision; Richard Rhodes, 'Dark Sun,' 1995
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