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The German nuclear weapon project ((ドイツ語:Uranprojekt); informally known as the ''Uranverein''; (英語:Uranium Society or Uranium Club)), was a clandestine scientific effort led by Germany to develop and produce nuclear weapons during World War II. This program started in April 1939, just months after the discovery of nuclear fission in December 1938, but ended only months later due to the German invasion of Poland, after many notable physicists were drafted into the ''Wehrmacht''. A second effort began under the administrative purview of the ''Wehrmacht's '' ''Heereswaffenamt'' on 1 September 1939, the day of the Invasion of Poland. The program eventually expanded into three main efforts: the ''Uranmaschine'' (nuclear reactor), uranium and heavy water production, and uranium isotope separation. Eventually it was assessed that nuclear fission would not contribute significantly to ending the war, and in January 1942, the ''Heereswaffenamt'' turned the program over to the Reich Research Council (''Reichsforschungsrat'') while continuing to fund the program. The program was split up among nine major institutes where the directors dominated the research and set their own objectives. Subsequently, the number of scientists working on applied nuclear fission began to diminish, with many applying their talents to more pressing war-time demands. The most influential people in the ''Uranverein'' were Kurt Diebner, Abraham Esau, Walther Gerlach, and Erich Schumann; Schumann was one of the most powerful and influential physicists in Germany. Diebner, throughout the life of the nuclear weapon project, had more control over nuclear fission research than did Walther Bothe, Klaus Clusius, Otto Hahn, Paul Harteck, or Werner Heisenberg. Abraham Esau was appointed as Hermann Göring's plenipotentiary for nuclear physics research in December 1942; Walther Gerlach succeeded him in December 1943. Politicization of the German academia under the National Socialist regime had driven many physicists, engineers, and mathematicians out of Germany as early as 1933. Those of Jewish heritage who did not leave were quickly purged from German institutions, further thinning the ranks of academia. The politicization of the universities, along with the demands for manpower by the German armed forces (many scientists and technical personnel were conscripted, despite possessing useful skills), would eventually all but eliminate a generation of physicists. At the end of the war, the Allied powers competed to obtain surviving components of the nuclear industry (personnel, facilities, and materiel), as they did with the V-2 program. ==Discovery of nuclear fission== In December 1938, German chemist Otto Hahn and his assistant Fritz Strassmann sent a manuscript to the German science journal ''Naturwissenschaften'' ("Natural Sciences") reporting they had detected and identified the element barium after bombarding uranium with neutrons.〔O. Hahn and F. Strassmann ''Über den Nachweis und das Verhalten der bei der Bestrahlung des Urans mittels Neutronen entstehenden Erdalkalimetalle'' (''On the detection and characteristics of the alkaline earth metals formed by irradiation of uranium with neutrons''), ''Naturwissenschaften'' Volume 27, Number 1, 11–15 (1939). The authors were identified as being at the ''Kaiser-Wilhelm-Institut für Chemie'', Berlin-Dahlem. Received 22 December 1938.〕 Their article was published on 6 January 1939. On 19 December 1938, eighteen days before the publication, Otto Hahn communicated these results and his conclusion of a ''bursting'' of the uranium nucleus in a letter to his colleague and friend Lise Meitner, who had fled Germany in July to the Netherlands and then to Sweden.〔Ruth Lewin Sime ''Lise Meitner's Escape from Germany'', ''American Journal of Physics'' Volume 58, Number 3, 263- 267 (1990).〕 Meitner, and her nephew Otto Robert Frisch, confirmed Hahn's conclusion of a ''bursting'' and correctly interpreted the results as being nuclear fission, a term coined by Frisch.〔Lise Meitner and O. R. Frisch ''Disintegration of Uranium by Neutrons: a New Type of Nuclear Reaction'', ''Nature'', Volume 143, Number 3615, 239–240 ((11 February 1939) ). The paper is dated 16 January 1939. Meitner is identified as being at the Physical Institute, Academy of Sciences, Stockholm. Frisch is identified as being at the Institute of Theoretical Physics, University of Copenhagen.〕 Frisch confirmed this experimentally on 13 January 1939.〔O. R. Frisch ''Physical Evidence for the Division of Heavy Nuclei under Neutron Bombardment'', ''Nature'', Volume 143, Number 3616, 276–276 ((18 February 1939) ). The paper is dated 17 January 1939. (experiment for this letter to the editor was conducted on 13 January 1939; see Richard Rhodes ''The Making of the Atomic Bomb'' 263 and 268 (Simon and Schuster, 1986). )〕〔In 1944, Hahn received the Nobel Prize for Chemistry for the discovery and the radiochemical proof of nuclear fission. Some American historians have documented their view of the history of the discovery of nuclear fission and believe Meitner should have been awarded the Nobel Prize with Hahn. See the following references: Ruth Lewin Sime ''From Exceptional Prominence to Prominent Exception: Lise Meitner at the Kaiser Wilhelm Institute for Chemistry'' (Ergebnisse 24 ) Forschungsprogramm ''Geschichte der Kaiser-Wilhelm-Gesellschaft im Nationalsozialismus'' (2005); Ruth Lewin Sime ''Lise Meitner: A Life in Physics'' (University of California, 1997); and Elisabeth Crawford, Ruth Lewin Sime, and Mark Walker ''A Nobel Tale of Postwar Injustice'', ''Physics Today'' Volume 50, Issue 9, 26–32 (1997).〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「German nuclear weapon project」の詳細全文を読む スポンサード リンク
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