Hahn, Otto

Hahn, Otto (ô`tō hän), 1879–1968, German chemist and physicist. His important contributions in the field of radioactivity include the discovery of several radioactive substances, the development of methods of separating radioactive particles and of studying chemical problems by the use of radioactive indicators, and the formation of artificial radioactive elements by bombarding uranium and thorium with neutrons. He received the 1944 Nobel Prize in Chemistry for splitting the uranium atom (1939) and discovering the possibility of chain reactions. The development of the atomic bomb was based on this work. Hahn was a member of the Kaiser Wilhelm Institute of Chemistry, Berlin, from 1912 and director from 1928 to 1944. He was in Allied custody (1944–46) and on his return to Germany became head of the Kaiser Wilhelm Gesellschaft, Göttingen (later reorganized as the Max Planck Gesellschaft).

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Hahn, Otto

(born March 8, 1879, Frankfurt am Main, Ger.—died July 28, 1968, Göttingen, W.Ger.) German physical chemist. He worked at the Kaiser Wilhelm Institute for Chemistry (1912–44), serving as director from 1928. With Lise Meitner he discovered several radioelements. In 1938, with Meitner and Fritz Strassmann (1902–80), he found the first chemical evidence of nuclear-fission products, created when they bombarded uranium with neutrons. For his discovery of nuclear fission, Hahn was awarded a 1944 Nobel Prize. He became president of the Max Planck Society; a respected public figure, he spoke out strongly against further development of nuclear weapons. In 1966 he shared the Enrico Fermi Award with Meitner and Strassmann.