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Randall S. Caswell

Headshot of Randall Caswell


Randall S. Caswell received his undergraduate education in physics at the University of Oregon prior to World War II. He then transferred to the Massachusetts Institute of Technology (MIT) and enrolled in the Reserve Officers’ Training Corps. He received a B.S. degree, was commissioned into the U.S. Army in 1945, and served in the Pacific campaign. After the war, he obtained his Ph.D. in physics at MIT with a thesis on the energies of beta rays, the high-energy electrons released by radioactive substances. He came to the National Bureau of Standards (NBS, now the National Institute of Standards and Technology, NIST) in 1952 to join the Neutron Physics Section. Caswell was promoted to chief of the Neutron Physics Section and served there from 1957 to 1969. After that, he was promoted to deputy director of the Center for Radiation Research, where he served from 1969 to 1978. From 1978 to 1994, Caswell held the position of chief of the Nuclear Radiation Division and then chief of the Ionizing Radiation Division. 

Notable honors and awards: 

  • Silver Medal, U.S. Department of Commerce, 1969
  • Gold Medal, U.S. Department of Commerce, 1979
  • Edward Bennett Rosa Award, National Institute of Standards and Technology, 1991
  • First recipient of the CIRMS Randall S. Caswell Award, 2000
  • Fellow, American Physical Society
  • Member, Consultative Committee for Ionizing Radiations of the Conference Generale des Poids et Mesures, 1969-89 

Other positions and appointments:

  • Adjunct professor, physics, American University, 1955-66
  • Teaching and research assistant, MIT, 1947-50
  • Associate professor, physics, University of Kentucky, 1950-52
  • Chairman, Science Panel of the White House Committee on Interagency Radiation Research and Policy Coordination
  • Member, International Commission on Radiation Units and Measurements (ICRU), 1975-99; secretary, 1979-99
  • Founding member, Council on Ionizing Radiation Measurements and Standards (CIRMS), 1992

Research interests: theoretical dosimetry; experimental neutron physics; neutron cross section calculations; biophysics; nanodosimetry and microdosimetry of neutrons and radon

Created July 26, 2019, Updated September 20, 2019