Louis Alexander Slotin (1 December 1910 – 30 May 1946) was a Canadian physicist and chemist who worked on the Manhattan Project. During World War II, Slotin conducted research at Los Alamos National Laboratory. He performed experiments with uranium and plutonium cores to determine their critical mass values. On 21 May 1946, Slotin was conducting a demonstration when he accidentally initiated a fission reaction, which released a burst of hard radiation. He received a lethal dose of radiation and died of acute radiation syndrome nine days later. Slotin was the second person to die from a criticality...