Thin Man (nuclear bomb) and the name came from the Dashiell Hammett detective novel "The Thin Man" and series of movies by the same name. The "Fat Man" bomb would be round and fat and was named after Sydney Greenstreet's character in "The Maltese Falcon". "Little Boy" would come last and be named only to contrast to the "Thin Man" bomb. Oppenheimer assembled a team at the Los Alamos Laboratory to work on plutonium gun design that included senior engineer Edwin McMillan and senior physicists Charles Critchfield and Joseph Hirschfelder. Critchfield had been working with sabots, which Oppenheimer believed would be required by the
Thin Man (nuclear bomb) Little Boy enriched uranium gun design, and almost all of the research at the Los Alamos Laboratory was re-oriented around the problems of implosion for the Fat Man 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