Edwin Mattison McMillan

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Edwin Mattison McMillan

Edwin Mattison McMillan (born September 18, 1907 in Redondo Beach , California , † September 7, 1991 in El Cerrito , California) was an American physicist. In 1951 he was awarded the Nobel Prize in Chemistry together with Glenn T. Seaborg .

Life

McMillan, the son of physicist Dr. Edwin Harbaugh McMillan and his wife Anne Marie McMillan, née Mattison, grew up in Pasadena, California. He studied at the California Institute of Technology , where he met Linus Pauling and graduated in 1928 with a B.Sc. , the following year as an M.Sc. He then moved to Princeton University , where he in 1932 when Edward Condon with a thesis on the deflection of particle beams in an inhomogeneous electric field ( "Deflection of a Beam of HCI Molecules in a Non-Homogeneous Electric Field") for Ph.D. PhD. In the same year, at the invitation of Professor Ernest O. Lawrence , he moved to the Faculty of Physics at the University of California at Berkeley on a national research grant , where he spent two years measuring the magnetic momentum of protons using the particle beam method. After another year he moved to the Berkeley Radiation Laboratory , where he studied nuclear reactions and their decay products at EO Lawrence, and he was also involved in the development of the cyclotron . From 1935 he held lectures there, in 1936 he was appointed Assistant Professor, 1941 Associate Professor and 1946 Professor.

He was the first scientist of a transuranic element produced artificially, and that this was neptunium in 1940 at the cyclotron in Berkeley . The uranium isotope 238 was bombarded with neutrons ; through neutron capture and subsequent beta-minus decay , uranium with the atomic number 92 became the element neptunium with the atomic number 93, with a half-life of 2.5 days. Another beta-minus decay results in plutonium with the atomic number 94. The plutonium isotope that is formed is much more stable than neptunium and could therefore also be chemically isolated. The order of the element names corresponds to the order of the outer planets Uranus , Neptune and the dwarf planet Pluto . McMillan published about Neptunium with Philip Abelson in 1940, after which such publications about transuranic elements were secret in the USA. After all, the article still provided valuable information to German physicists in the uranium project, including Carl Friedrich von Weizsäcker , who deduced from it that plutonium and not neptunium was an element that could possibly be used for building atomic bombs and "breeding" from uranium-238 by neutron bombardment.

During the Second World War he worked on military projects such as radar , sonar and nuclear weapons , from November 1942 with Robert Oppenheimer in the Los Alamos Laboratory . After the Second World War, from 1945 onwards, he developed and built the first electron synchrotron . From 1958 to 1973 he was director of the Lawrence Radiation Laboratory at the University of California.

McMillan worked for some time at CERN on a sabbatical in 1975 , where he participated in one of the muon g-2 experiments at CERN's muon storage ring.

In 1951, he and Glenn T. Seaborg received the Nobel Prize in Chemistry for their work in the field of transuranic elements . On October 24, 1963, he and Wladimir Weksler were awarded the Atoms for Peace Award for their independent contributions to accelerator technology . In 1990 he was awarded the National Medal of Science .

McMillan was a fellow of the American Physical Society and the American Academy of Arts and Sciences (1962), he was a member of the National Academy of Sciences and the American Philosophical Society . In 1954 he was recognized by his faculty for the comprehensibility of his lectures. From 1954 to 1958 he was a member of the General Advisory Committee of the Atomic Energy Commission . In 1960 he was accepted into the Commission for High Energy Physics of the International Union of Pure and Applied Physics .

In 1961 he was awarded an honorary doctorate from the Rensselaer Polytechnic Institute and in 1963 from Gustavus Adolphus College .

At the time of his tenure at Berkeley School of Physics, he married Elsie Walford Blumer, the daughter of Dr. George Blumer, former dean of Yale Medical School. The couple have three children, Ann Bradford (1943), David Mattison (1945) and Stephen Walker (1949).

literature

Web links

Commons : Edwin McMillan  - Collection of Images, Videos and Audio Files

Remarks

  1. ^ Edwin McMillan, Philip Abelson, Radioactive element 93, Phys. Rev., Volume 57, 1940, 1185
  2. David J. Jackson, WKH Panofsky: Edwin Mattison McMillan 1907-1991 : A Biographical Memoir . In: Biographical Memoirs . tape 69 . National Academy Press, 1996, pp. 215–241 ( nasonline.org [PDF; accessed August 1, 2019]).
  3. "His teaching is notable for the clarity and simplicity with which he presents even the most complex scientific facts and theories." (according to LBNL)