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Harold Lyons Atomic Clocks Collection,

Extent and Forms of Material: 2 cubic feet (6 boxes)
Creator: Harold Lyons
Abstract: Dr. Harold Lyons was a physicist whose primary interest was in atomic frequency standards and atomic clocks. The collection documents Dr. Lyons and his work with atomic clocks. The collection includes his research as manifested in published papers, presentations, reports, correspondence, laboratory notes, photographs and diagrams.
Repository: Archives Center, National Museum of American History, Smithsonian Institution, Washington, D.C.; ; 202-633-3270;
Collection Number: AC0701
Processing Note: Processed by Jeanne Sklar, intern, August 2001; supervised by Alison Oswald, archivist.
© 2007 by the Smithsonian Institution. All rights reserved.


Information for users of the collection

Conditions Governing Access: The collection is open for research use.
Physical Access: Researchers must handle unprotected photographs with gloves. Researchers must use reference copies of audio-visual materials. When no reference copy exists, the Archives Center staff will produce reference copies on an “as needed” basis, as resources allow.
Conditions Governing Reproduction and Use: Copyright held by the Smithsonian Institution. Collection items available for reproduction, but the Archives Center makes no guarantees concerning copyright restrictions. Reproduction permission from Archives Center: fees for commercial use.
Preferred Citation: [Title and date of item], Harold Lyons Atomic Clocks Collection, Archives Center, National Museum of American History, box number X, folder number XX, digital file number XXXXXXXX


In-depth information about the collection

Administrative/biographical history
Scope and content
System of arrangement
Acquisition information
Related archival materials
Related artifacts
Access points
Container listing

Administrative/biographical history

Harold Lyons was born February 16, 1913 in Buffalo, New York, and attended the University of Buffalo, graduating summa cum laude with a B.S. in Physics in 1933. After obtaining a Ph.D. in Nuclear Physics from the University of Michigan in 1939, he worked at the Naval Research Laboratories for two years and then joined the National Bureau of Standards (NBS) in 1941. In 1944, he was appointed chief of the Microwave Standards Section of an Interservice Radio Propagation Laboratory (IRPL) established at the NBS during World War II. He continued in that position after the war when the IRPL, in 1946, was reconstituted as the Central Radio Propagation Laboratory (CRPL).

Lyons’s work on microwave frequency standards led directly to his interest in atomic frequency standards and atomic clocks. On his initiative a substantial program of research and development was pursued in the Microwave Standards Section from 1948-1951. There under his direction the first operative atomic clock, based on the absorption of microwaves of ammonia, was constructed in 1948 and announced in early 1949.

Lyons remained with the CRPL after it was moved to Boulder, Colorado, in 1954, but left a year later to work in Hughes Aircraft Company’s Culver City, California, research labs. Here he continued his atomic physics research, particularly applications for the atomic clock, including satellite technology, and expanding to development work in lasers. He continued his work on lasers at Electro-Optical Systems Quantum Physics Division from 1960-1962. In the late 1960s and during the 1970s, he was an independent physics consultant and conducted research through an association with the University of California, Los Angeles.

Harold Lyons died March 23, 1998 in Los Angeles, California.

Scope and content

The Harold Lyons Papers, 1935-1991, show his professional interests, especially his research from the 1950s, as manifested in published papers, presentations, reports, correspondence, laboratory results, and photographs. The bulk of the collection consists of papers and presentations of Lyons and others in the atomic physics field. Most of Lyons’s work and the materials he collected address different aspects of microwave frequency.

Formats represented in the collection include published articles, typewritten and handwritten manuscripts, typewritten and handwritten personal correspondence, memorandums, photographs, diagrams, laboratory results, pamphlets, and newspaper clippings. The collection is arranged into five series.

Series 1, Biographical Information, 1955-1965; 1973, contains copies of Lyons’s curriculum vitae (circa 1955, 1962, and 1971) and his entries in Who’s Who in America and Who’s Who in The West. This series also has two folders with materials relating to two honors he received, the Franklin Institute Certificate of Merit, in 1958, and the U.S. Department of Commerce’s 25th Commemorative Award in 1973.

Series 2, Papers and Presentations, 1947-1962; 1973-1974, contains the journal articles and papers authored by Lyons and the conference and special presentations he gave during his career, most of which address research for aspects of the atomic clock. Included are papers he authored published in the Journal of Applied Physics, American Scholar, Scientific American, and Annals of the New York Academy of Sciences and presentations given at the National Bureau of Standards for the anniversary of the atomic clock.

Series 3, Correspondence, 1949-1991, contains general correspondence for the years 1949-1966, 1978, 1987, and 1991, as well as correspondence with the following individuals: Dirk Brouwer, Paul Forman, Polykarp Kusch, Koichi Shimoda, Wilbert F. Snyder, Charles H. Townes, and Jerrold R. Zacharias. The bulk of this series is incoming correspondence addressed to Lyons, although he did retain some copies of outgoing correspondence.

Series 4, Research, 1947-1958; 1970-1991, contains laboratory results for deuterated ammonia (via strip chart recordings) and general cesium atomic beam experiments through calibration of magnetic fields, calculation of c-fields in the magnetic chamber, and atomic beam measurements. It also contains brief information on other research interests, such as the International Scientific Radio Union, and scattered promotional materials for natural health and electrical products. In addition, this series contains a copy of the patent granted to Lyons and Benjamin F. Husten in 1955 for the atomic clock and photographs and diagrams relating to Lyons’s work on the atomic clock. Included are black and white photographs of Lyons and his colleagues with views of the clock as well as diagrams and charts included in published and unpublished work and presentations. Most of the photographs and diagrams are undated and unlabeled.

Series 5, Collected Background Research Materials, 1935-1982, contains papers and presentation materials focused on atomic physics, including papers published in journals, memoranda, technical reports, conference programs, and conference proceedings. One folder in this series has materials relating to the promotion of the atomic clock through pamphlets, speeches, papers, and one oversize item of reproduced newspaper clippings. A folder relating to a university course of lectures, most likely authored by Polykarp Kusch of Columbia University, on molecular beams is also included in this series. In addition, this series contains copies of two patents, one granted to Friedrich H. Reder in 1960 for molecular resonance devices, and the other, an Australian patent, applied for in 1958, for an invention dealing with a frequency selective method and system.

System of arrangement

The collection is arranged into five series.
Series 1: Biographical Information, 1955-1965; 1973
Series 2: Papers and Presentations, 1947-1962; 1973-1974
Subseries 1, Publications, 1947-1948; 1950-1953; 1957; 1959-1960; 1962; undated
Subseries 2, Presentations, 1946-1958; 1973-1974
Series 3: Correspondence, 1949-1991
Series 4: Research, 1947-1958; 1970-1991
Subseries 1, Laboratory Findings, 1952-1954; undated
Subseries 2, Other Research Interests, 1947-1957; 1970-1991
Subseries 3, Photographs and Diagrams, 1957; undated
Series 5: Collected Background Research Materials, 1935-1982

Acquisition information

This collection was donated to the Archives Center by Harold Lyons’s daughter, Sherrie L. Lyons, in January, 2000.

Related archival materials

Archives Center collection #547, The Atomic Clock Collection, 1955-1968, contains related archival materials, principally on the development of the first commercial atomic clock, the Atomichron.

Related artifacts

The Division of Information, Technology and Communication holds the first operative atomic clock, constructed under Lyons’s direction at the National Bureau of Standards in 1948.

Access points

Atomic clocks
Atomic absorption spectroscopy
Atomic frequency standards
Time—Systems and standards

National Bureau of Standards

Laboratory notebooks
Technical notes

Container listing

Box Folder  
1 1 Curriculum Vitae and Biographical Data, 1955-1965
  2 Franklin Institute Certificate of Merit, 1958
  3 U.S. Department of Commerce 25th Commemorative Award, 1973
    SERIES 2: PAPERS AND PRESENTATIONS, 1947-1962; 1973-1974
    Subseries 1, Publications, 1947-1948; 1950-1953; 1957; 1959-1960; 1962; undated
  4 Cesium, Atomic Beam Frequency Standard, undated
  5 The Microwave Frequency Standard, 1947
  6 Microwave Frequency Measurements, 1948
  7 Microwave Frequency Dividers, 1950
  8 The Atomic Clock, A Universal Standard, 1950
  9 Microwave Measurement of the Dielectric Properties of Gases, 1950-1951
  10 Spectral Lines as Frequency Standards, 1952
  11 Microwave Absorption Spectrum of ND3, 1953
  12 Atomic Clocks, 1957
  13 The Amazing Maser, 1959; Maser, Iraser, and Laser, 1960
  14 Molecular Beam Devices, 1962
    Subseries 2, Presentations, 1946-1958; 1973-1974
  15 Presentations, 1946-1958
  16 National Bureau of Standards, 1973
  17 National Bureau of Standards, 1974
2 1-2 General Correspondence, 1949-1991
  3 Dirk Brouwer, 1951-1955
  4-5 Paul Forman/Smithsonian, 1982-1985; 1990
  6 Polykarp Kusch, 1949-1956
  7 Koichi Shimoda, 1955-1957
  8-11 Wilbert F. Snyder, 1950-1966; 1978; 1987
  12 Charles H. Townes, 1954-1955
  13 Jerrold R. Zacharias, 1952-1953
    SERIES 4: RESEARCH, 1947-1958; 1970-1991
    Subseries 1, Laboratory Findings, 1952-1954; undated
3 1 Deuterated Ammonia, undated
  2 Cesium Atomic Beams, undated
  3 Magnetic Field Calibrations, undated; 1952-1954
  4 C-Field Calculation, undated; 1952
  5 Atomic Beam Measurements, undated; 1952
    Subseries 2, Other Research Interests, 1947-1957; 1970-1991
  6 International Scientific Radio Union, undated, 1947-1957; 1978
  7 Health and Product-Related, undated; 1970, 1981, 1990-1991
3 8 Miscellaneous Notes and Papers, undated
  9 Patent, 1958
    Subseries 3, Photographs and Diagrams, 1957; undated
  10 Photographs, undated
  O/S Folder 1 Photographs, undated
3 11 Diagrams, undated, 1957
  O/S Folder 1 Diagrams, undated
3 12-13 Publications and Papers, undated
4 1 Publications and Papers, 1935-1953
  2-5 Publications and Papers, 1954-1959
5 1-3 Publications and Papers, 1959-1979
  O/S Folder 1 Atomic Clock Promotional Material, 1955
5 4 Atomic Clock Promotional Material, undated
  5 Presentations and Conference Materials, 1950-1982
  6 Molecular Beams Course, undated
  7 Patents, 1958; 1960



Last Update: 27 Jun 2007

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