Thin Man (nuclear bomb) Thin Man (nuclear bomb) "Thin Man" was the code name for a proposed plutonium gun-type nuclear bomb using plutonium-239 which the United States was developing during the Manhattan Project. They aborted its development when they discovered that the spontaneous fission rate of their nuclear reactor-bred plutonium was too high for use in a gun-type design, due to the high concentration of the isotope plutonium-240. In 1942, prior to the Army taking over wartime atomic research, Robert Oppenheimer held conferences in Chicago in June and Berkeley, California, in July at which various engineers and physicists discussed nuclear bomb design issues. A
Atomic Bomb Casualty Commission Atomic Bomb Casualty Commission The Atomic Bomb Casualty Commission (ABCC) was a commission established in 1946 in accordance with a presidential directive from Harry S. Truman to the National Academy of Sciences-National Research Council to conduct investigations of the late effects of radiation among the atomic-bomb survivors in Hiroshima and Nagasaki. As it was erected purely for scientific research and study, not as a provider of medical care and also because it was heavily supported by the United States, the ABCC was generally mistrusted by most survivors and Japanese alike. It operated for nearly thirty years before its dissolution in