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thumb Herbert Lawrence Anderson (May 24, 1914 – July 16, 1988) was an American nuclear physicist who contributed to the Manhattan Project. He was also a member of the team which made the first demonstration of nuclear fission in the United States, in the basement of Pupin Hall at Columbia University. He participated in the first atomic bomb test, codenamed Trinity. After the close of World War II, he was a professor of physics at the University of Chicago until 1982. There, he helped Fermi establish the Enrico Fermi Institute and was its director from 1958 to 1962. The latter part of his career was as a senior fellow at Los Alamos National Laboratory. He was a recipient of the Enrico Fermi Award. Anderson's lineage to Rabbi Meir Katzenellenbogen, the Maharam of Padua, is detailed in ''The Unbroken Chain''.〔Rosenstein, Neil. ''The Unbroken Chain: Biographical Sketches and Genealogy of Illustrious Jewish Families from the 15th-20th Century'', Volumes 1 and 2, Revised Edition, CIS Publishers: New York, 1990. ISBN 0-9610578-4-X〕 ==Education== Born in New York, New York, Anderson earned three degrees as Columbia University, a Bachelor of Arts in 1931, a Bachelor of Science in electrical engineering in 1935, and a PhD in 1940.〔Harold M. Agnew '' Biographical Memoirs: (Herbert L. Anderson )'' (National Academy of Sciences).〕 John R. Dunning, professor of physics at Columbia, closely followed the work of Ernest Lawrence on the cyclotron. Dunning wanted a more powerful neutron source and the cyclotron appeared as an attractive tool to achieve this end. During 1935 and 1936, he was able to construct a cyclotron using many salvaged parts to reduce costs and funding from industrial and private donations. The cyclotron design and building project began as Anderson was completing his engineering degree. At the suggestion of Professor Dana Mitchell, Dunning offered Anderson a teaching assistant position if he would also help with the design and building of the cyclotron. While working on his doctorate, Anderson made two major contributions to the project. The first was to design a high frequency filament supply, rather than the commonly used direct current version. This fostered longer filament life in the high magnetic field environment of a cyclotron. The second and more important contribution was the use of a pair of concentric lines to feed the cyclotron dees (cyclotron electrodes in the shape of a “D”), rather than the usual induction system. This refinement resulted in greater cyclotron efficiency and thereafter became a regular feature in cyclotron design. Others assisting Anderson in the construction of the cyclotron were Eugene T. Booth, G. Norris Glasoe, Hugh Glassford, and, of course, professor Dunning. In anticipation of conducting experiments with the cyclotron, Anderson also built an ionization chamber and a linear amplifier in late 1938.〔〔Broad, William J. ''Columbia’s Historic Atom Smasher Is Now Destined for the Junk Heap'', ''New York Times'' (20 December 2007 ). (PDF ).〕〔Herbert L. Anderson ''(John Ray Dunning 1907 – 1975 )'' in ''Biographical Memoir'' 163-186 (National Academy of Sciences, 1989). 〕 In December 1938, the German chemists Otto Hahn and Fritz Strassmann sent a manuscript to ''Naturwissenschaften'' reporting they had detected 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.〕 simultaneously, they communicated these results to Lise Meitner. Meitner, and her nephew Otto Robert Frisch, correctly interpreted these results as being nuclear fission.〔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 January 13, 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 of nuclear fission. Some historians have documented the history of the discovery of nuclear fission and believe Meitner should have been awarded the Nobel Prize with Hahn.〔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).〕〔Elisabeth Crawford, Ruth Lewin Sime, and Mark Walker ''A Nobel Tale of Postwar Injustice'', ''Physics Today'' Volume 50, Issue 9, 26-32 (1997).〕 Even before it was published, Meitner’s and Frisch’s interpretation of the work of Hahn and Strassmann crossed the Atlantic Ocean with Niels Bohr, who was to lecture at Princeton University. Isidor Isaac Rabi and Willis Lamb, two University of Columbia physicists working at Princeton, heard the news and carried it back to Columbia. Rabi said he told Fermi; Fermi gave credit to Lamb. Bohr soon afterwards went from Princeton to Columbia to see Fermi. Not finding Fermi in his office, Bohr went down to the cyclotron area and found Anderson. Bohr grabbed him by the shoulder and said: “Young man, let me explain to you about something new and exciting in physics.”〔Richard Rhodes ''The Making of the Atomic Bomb'' 268 (Simon and Schuster, 1986).〕 It was clear to scientists at Columbia that they should try to detect the energy released in the nuclear fission of uranium from neutron bombardment. On January 25, 1939, Anderson was a member of the experimental team at Columbia University that conducted the first nuclear fission experiment in the United States,〔H. L. Anderson, E. T. Booth, J. R. Dunning, E. Fermi, G. N. Glasoe, and F. G. Slack ''The Fission of Uranium'', ''Phys. Rev.'' Volume 55, Number 5, 511 - 512 (1939). Institutional citation: Pupin Physics Laboratories, Columbia University, New York, New York. Received 16 February 1939.〕 which was conducted in the basement of Pupin Hall; the other members of the team were Eugene T. Booth, John R. Dunning, Enrico Fermi, G. Norris Glasoe, and Francis G. Slack.〔Richard Rhodes ''The Making of the Atomic Bomb'' 267-270 (Simon and Schuster, 1986).〕 Fermi had arrived at Columbia only a short time before this historic demonstration. This bringing together of Fermi and Anderson resulted in a rewarding relationship lasting until the death of Fermi in 1954. Fermi and Anderson conducted a series of experiments at Columbia on the slowing down of neutrons in graphite, absorption and reflection of slow neutrons by numerous relevant materials, fissioning of uranium, and preliminary experiments using a lattice of uranium in graphite. A paper based on Anderson’s PhD thesis, ''Resonance Capture of Neutrons by Uranium'',〔Herbert L. Anderson ''Resonance Capture of Neutrons by Uranium'', ''Phys. Rev.'' Volume 80, Issue 4, 499 - 506 (1950). Institutional citation: Columbia University, New York, New York. Received 27 April 1940.〕 for security reasons, was not published until 10 years later.〔 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「Herbert L. Anderson」の詳細全文を読む スポンサード リンク
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