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Robert F. Bacher Papers

Identifier: 10105-MS

Scope and Content

Robert Fox Bacher began donating his papers to the Archives at the California Institute of Technology in 1989. Comprising of 72 boxes and approximately forty linear feet, the collection encompasses most of Bacher's distinguished career. The scientific work represented in the collection includes his early research in the physics laboratory of the University of Michigan, his experimental labors for the Manhattan Project and, at the California Institute of Technology, his participation in the high-energy synchrotron. The majority of the collection is devoted to Bacher's administrative duties, consulting services and professional work. This includes Bacher's work as head of experimental physics in Los Alamos, his involvement in the fledgling UN Atomic Energy Commission, his role in the President's Science Advisory Committee (PSAC) and his responsibilities within the Universities Research Association (URA). As head of physics and as Provost, Bacher was also an influential administrator at Caltech, and his substantial involvement in the various affairs of the Institute are well represented in the collection. In addition to the extensive documents in the collection are a considerable number of photographs and artifacts which testify to the considerable breadth of Bacher's career.


  • 1924-1994



The collection is open for research. Researchers must apply in writing for access.

Publication Rights

Copyright may not have been assigned to the California Institute of Technology Archives. All requests for permission to publish or quote from manuscripts must be submitted in writing to the Caltech Archivist. Permission for publication is given on behalf of the California Institute of Technology Archives as the owner of the physical items and, unless explicitly stated otherwise, is not intended to include or imply permission of the copyright holder, which must also be obtained by the reader.


Robert Fox Bacher was born in 1905 in Loudenville, Ohio. He attended the University of Michigan, receiving a BS degree in 1926 and a PhD in 1930. His research in the early 1930s focused on spectroscopy and nuclear physics, concentrating on atomic energy states and hyperfine structures. Many of his early papers were collaborative in nature, and included work with Samuel Goudsmit, with whom he coauthored Atomic Energy States in 1932.

In 1935 Bacher joined the faculty at Cornell University, where he concentrated on such subjects as neutron scattering and the development of new techniques for exploring the inner structure of the atom with bubble and cloud chambers. Also, he co-wrote with H. A. Bethe and M. S. Livingston several famous articles on nuclear physics, many of which were republished in Reviews of Modern Physics and which for years remained a standard textbook in the field.

During World War II, he worked first in the radar program at the MIT Radiation Laboratory, under Lee DuBridge. After Robert Oppenheimer urged him to do so, Bacher moved to Los Alamos to work on the Manhattan Project in 1943. There, he served first as head of the division of experimental physics (1943-1944), then as head of the bomb physics division (1944-1945). As such, Bacher was a key figure in the construction of the atomic weapons that exploded at Trinity site in July of 1945 and then over Hiroshima and Nagasaki the following month.

After the war Bacher returned to Cornell as professor of physics but soon thereafter relocated to Washington to serve as one of the first members of the new United States Atomic Energy Commission. As a member of this new government organization, Bacher participated in many of the meetings of the fledgling United Nations Atomic Energy Commission and therefore played a significant role in the formation of national and international policy concerning the use of atomic energy and nuclear weapons.

In 1949, Bacher finally accepted an offer to come to Caltech as chairman of the Division of Physics, Mathematics and Astronomy, a position that he held for thirteen years. As chairman, he initiated and promoted numerous programs of considerable importance to the Institute, including the construction of the new electron synchrotron which by the summer of 1952 was operating at 500 Mev. Bacher was also responsible for enlisting key members of Caltech's research group in particle physics, led by professors Richard P. Feynman and Murray Gell-Mann. He also played a significant part in "Project Vista" in the summer of 1951. Although his time as an experimental physicist dwindled during these years, Bacher nonetheless retained a keen interest in the development of particle physics and ensured Caltech remained at the forefront of the discipline.

In 1961, the Institute realized that it needed a highly-skilled administrator to deal with the increasingly complex activities of the campus. With the blessing of the Divisions, the President and the Board of Trustees, Caltech created the new position of Provost and in 1962 Bacher became its first incumbent. As Provost, his activities centered on the development of the divisions, but also included various venture funds, plans to implement computing resources and faculty ethics. In 1969, Bacher was appointed Vice-president as well, and even after resigning from this position and the provostship his administrative duties remained significant: he was instrumental in the development of the Owens Valley Radio Observatory for radio astronomy, he sat on a number of committees at the Jet Propulsion Laboratory and he continued to influence many of the important policies at Caltech.

Meanwhile, Bacher's influence outside of the California Institute of Technology remained strong. After resigning from the Atomic Energy Commission, he continued to counsel the President as a member of the President's Science Advisory Committee (PSAC) while he also participated in the activities of a host of corporations and professional organizationsthe American Physical Society, Edison Electric, the Hughes Aircraft company, the Claremont colleges, the National Academy of Sciences, Rand Corporation and the Universities Research Association to name but a few. In addition, Bacher's opinion concerning nuclear power and weapons was sought the world over, and for this reason he remained an important sounding board for such associations as The California Seminar on Arms Control and Foreign Policy and the Bulletin of the Atomic Scientists. By 1990, however, Bacher had considerably curtailed these activities, and moved to Montecito, California. He died in 2004.


40 linear feet (72 boxes)

Language of Materials





The working papers, correspondence, publications, photos and biographical materials of Robert F. Bacher (1905-2004) form the collection known as the Papers of Robert F. Bacher in the Archives of the California Institute of Technology. Bacher was a nuclear physicist who during World War II worked on radar at the MIT Radiation Laboratory and then from 1943 at Los Alamos on the atomic bomb. He was one of the first members of the US Atomic Energy Commission (1946-49). He served on the faculty and in the administration of the California Institute of Technology from 1949 until his retirement in 1976.


Series 1, Bacher's correspondence, encompasses approximately ten per cent of the collection and ranges from the late nineteen-twenties to the early nineties. Notably, there is extensive correspondence between Bacher and Hans Bethe, Samuel Goudsmit and J. Robert Oppenheimer. A number of Nobel recipients are represented in this series as well, including Albert Einstein, Richard Feynman, Robert A. Millikan, Neils Bohr, Enrico Fermi, Linus Pauling, Bertrand Russell and William Fowler. Although the bulk of correspondence related to Caltech is housed in Series 6, there are numerous letters by such correspondents as Harold Brown, Lee DuBridge and Richard Tolman.

Series 2 of the collection is a combination of Bacher's pre-war laboratory investigations, his research and managerial duties in Los Alamos and, also, later accounts of the Manhattan Project. His pre-war work, from the University of Michigan and Cornell University, includes notebooks, teaching material and the research notes that led to his publications. The second sub-series of the series houses material from the second world war: correspondence and notes from the MIT Radiation Laboratory; documents related to the organization of the various divisions at Los Alamos; correspondence with J. Robert Oppenheimer and Richard Tolman; and documents concerning the explosion of the first nuclear device. (Researchers should see also Series 1 for additional correspondence with Tolman and Oppenheimer, and Series 5.3 for additional material relating to Oppenheimer.) The final sub-series of the series contains reports and reminiscencesboth published and manuscriptof the atomic bomb project at Los Alamos.

Series 3 provides detailed accounts of Bacher's diverse activities in conjunction with the US Government. While the series includes documents concerning his work for governmental branches such as the Air Force and the President's Science Advisory Committee (PSAC), the bulk of the material relates to his office within the US Atomic Energy Commission.

Series 4 evinces Bacher's tremendous abilities as an administrator. Among the professional organizations in which he was involved are the National Academy of Sciences, the International Union of Pure and Applied Physics (IUPAP), the International Council of Scientific Unions (ICSU) and the Universities Research Association (URA).

Series 5, "Post-War nuclear security, arms control and nuclear energy," is closely related to both the third and fourth series: The first sub-series consists of much of Bacher's "unofficial" involvement in the debates about atomic weapons and defense, while the second revolves around atomic energy for domestic use. Additionally, the final sub-series is devoted to J. Robert Oppenheimer, and comprises writings by Oppenheimer, documents and ephemera relating to the USAEC's Commission in the Matter of J. R. Oppenheimer, and numerous sketches of Oppenheimer's life.

Series 6 contains material that relates directly to the California Institute of Technology. Each sub-series is organized in chronological order, starting with the oldest material. Because of Bacher's heavy involvement in the project, the first sub-series deals principally with the Caltech synchrotron, its operation and its eventual shut-down. (Researchers should be aware that the Archives has a separate collection dealing exclusively with the Caltech synchrotron.). However, since Bacher was head of physics the sub-series also houses material related to other activities as well: organization of and planning for the Division of Physics, Mathematics and Astronomy; exchange programs with other laboratories; and matters concerning astronomical observatories. The second sub-series concerns Bacher's provostship and therefore involves a diverse array of matters in which the Institute was involved, ranging from planning for the future of the divisions to disciplinary actions against Linus Pauling. Similarly, the fourth, fifth and sixth sub-series involve various institutional matters, albeit during the years when Bacher was not Caltech's Provost.

Series 7 and Series 8 are somewhat more personal in nature. Series 7 consists of Bacher's own writings and talks, as well as a number of interviews that Bacher gave, mostly during the 1980s. The writings include dozens of pre-war scientific reprints, but also numerous non-technical publications from the 1940s-1980s. However, the series also contains over twenty manuscripts of talks and lectures on various subjects ranging from arms control to reminiscences of the Manhattan Project, although researchers should note that Bacher's biographical sketch of Oppenheimer is contained in Series 5.3.

Series 8, "Biographical Material," contains documents and objects spanning eight decades. It includes souvenirs and memorabilia, diaries, newspaper clippings, ID cards and numerous awards. Bacher was also a fanatical note-taker, and the series also contains copious "notes to self."

Series 9 includes Bacher's extensive reprint collection. Containing some of the most important research papers published in the twentieth century, the collection not only reflects the development of nuclear physics from the 1930s through the 1960s but also how an individual's--i.e. Bacher's--research interests and extensive collegial network evolved over time.

Series 10 contains an assortment of images and objects that span seven decades. Within the first sub-series are both photographs and glass slides, including images of the Manhattan Project, particle accelerators and astronomical observatories. Also, there are numerous portraits of Bacher and photos of committees of which Bacher was part. The artifacts in the second sub-series are various, ranging from radiation detectors to a musical recording of Bacher's retirement ceremony.

Physical Location

California Institute of Technology, Caltech Archives

Acquisition Information

Robert F. Bacher began donating his papers to the Caltech Archives in 1989. The donation was completed by his children in several installments, ending in 2000.

Related Material

Papers of Lee A. DuBridge

Papers of William A. Fowler

Papers of Robert L. Walker

Records of the Caltech Synchrotron Laboratory

Papers of Murray Gell-Mann

Robert Bacher collection, Los Alamos National Laboratory

Interview with Robert F. Bacher

A summary of the Bacher holdings in the Caltech Archives, including photos and audio-video material, may be obtained through the Caltech Archives web site.

Items Removed from Papers

The followings books, which contain contributions from Robert Bacher, were removed from the collection and deposited in the library of the Archives:

Bacher, Robert and Goudsmit, Sam. Atomic energy states, as derived from the analyses of optical spectra (New York, London, McGraw–Hill Book Company, inc., 1932)

"The H Bomb," in The H Bomb (New York, Didier, 1950)

"Looking to the Future," in Brown, Sanborn, ed., Physics; 50 years later (Washington, National Academy of Sciences, 1973)

"The new era of particle physics" in Killian, James ed., Proceedings of the Atoms for Peace awards (Cambridge, Mass., MIT Press, 1978)

"The career of Hans Bethe," in Marshak, R.E. ed., Perspectives in modern physics; essays in honor of Hans A. Bethe (New York, Interscience Publications, 1966)

Atomic Energy and national security," in Proceedings of the National Congress of Parents and Teachers. Vol. 54 (Chicago, 1950)

"Stationary states of nuclei," (with Hans Bethe) in Basic Bethe (New York, American Institute of Physics, 1986)

The following books from the Bacher collection were integrated into the Caltech Archives' library: persons wishing to consult these monographs should refer to the catalog of the Caltech Library System.

A Commemorative Report Sponsored by the Union of Concerned Scientists. Toward a New Security: Lessons of the Forty Years Since Trinity, July 16, 1985.

Ackland, Len, Steven McGuire, eds. Assessing the Nuclear Age, 1986.

Adamczewski, Jan. Nicolaus Copernicus and his Epoch, undated

Adams, Ruth and Susan Cullen, eds. The Final Epidemic: Physicians and Scientists on Nuclear War. 1981.

Alexanderson, E. Pauline, ed. Fermi–I: New Age for Nuclear Power, 1979.

Annals of The Sunset Club of Los Angeles. Vols. 4 and 6. 1957, 1986.

Aristotle's Physics, translated by Richard Hope, 1961.

Arms Control Association. Arms Control and National Security: An Introduction, 1989.

Arms Control Association. Foundation for the Future: The ABM Treaty and National Security, 1990.

Becker, Abraham S. Military Expenditure Limitation for Arms Control: Problems and Prospects, 1977.

Bethe, Hans A. and Frederic De Hoffmann. Mesons and Fields, Vol. II: Mesons, undated

Blackett, P. M. S. Military and Political Consequences of Atomic Energy, 1948.

Blanpied, William A., ed. Impacts of the Early Cold War on the Formulation of U.S. Science Policy, 1995.

Brown, Harold. Thinking About National Security: Defense and Foreign Policy in a Dangerous World, 1983.

Bush, Vannevar. Modern Arms and Free Men, 1949.

Byerly, William Elwood. An Elementary Treatise on Fourier's Series, 1893.

Cairns, John, Gunther S. Stent and James D. Watson, eds. Phage and the Origins of Molecultar Biology, 1966.

California Legislature. Fifth Report of the Senate Fact–Finding Committee on Un–American Activities, 1949.

Carhart, Henry S., and Horatio N. Chute. Practical Physics, 1920.

Carnegie Endowment for International Peace. The United States, Japan, and the Future of Nuclear Weapons, 1995.

Clausen, Peter, Allan Krass, Robert Zirkle. In Search of Stability: An Assessment of New U.S. Nuclear Forces, A Report by the Union of Concerned Scientists, 1986.

Cleveland, Harlan, and Gerard J. Mangone, and John Clarke Adams. The Overseas Americans, 1960.

Cohen, E. Richard, Kenneth M. Crowe, and Jessse W. M. DuMond. The Fundamental Constants of Physics, 1957.

Columbia University. The Nuclear Power Controversy, 1976.

Committee for Economic Development. Achieving Energy Independence, December 1974.

Crease, Robert P. and Charles C. Mann. The second creation: makers of the revolution in 20th century physics, 1986.

Daedalus, Journal of the American Academy of Arts and Sciences, Fall 1960.

Darrow, Karl K. Atomic Energy, 1948.

Deitchman, Seymour J. Limited War and American Defense Policy, 1964.

Dennis, Jack, ed. The Nuclear Almanac: Confronting the Atom in War and Peace, 1984.

Drell, Sidney D. Facing the threat of nuclear weapons, 1983.

DuBridge, Lee A. Introduction to Space, 1960.

Esslinger, William. Politics and Science, 1955.

Fermi, Enrico. Elementary Particles, 1951.

Gándara, Arturo. Electric Utility Decision making and the Nuclear Option, June 1977.

Glasstone, Samuel, ed. The Effects of Nuclear Weapons, U.S. Atomic Energy Commission, June 1957.

Goudsmit, Samuel A. Alsos, 1947.

Gowing, Margaret. Britain and Atomic Energy, 1939–1945, 1965.

Green, Constance McLaughlin, and Milton, Lomask. Vanguard: A History, 1970.

Grodzins, Morton, and Eugene Rabinowitch, eds. The Atomic Age: Scientists in National and World Affairs, 1965.

Haskins, Caryl P., ed. The Search for Understanding, 1967.

Hecht, Selig. Explaining the Atom, 1947.

Hedrick, Earle Raymond. Logarithmic and Trigonometric Tables, 1920.

Herken, Gregg. Cardinal Choices: Advising from the Atomic Bomb to SDI, 1992.

Herken, Gregg. The Winning Weapon: The Atomic Bomb In The Cold War, 1945–1950, 1982.

Hewlett, Richard G. and Francis Duncan. Atomic Shield, 1947/1952, 1969.

Hewlett, Richard G., Oscar E. Anderson, Jr. The New World, 1939/1946, 1962.

Hoffman, Joseph G. The Size and Growth of Tissue Cells, 1953.

Horelick, Arnold L., Myron Rush. Strategic Power and Soviet Foreign Policy, 1966.

Hosmer, Stephen T., Thomas W. Wolfe. Soviet Policy and Practice Toward Third world Conflicts, 1983.

IEEE Center for the History of Electrical Engineering. Rad Lab: Oral Histories Documenting World War II Activities at the MIT Radiation Laboratory, 1993.

Jet Propulsion Laboratory. Solar Energy in Buildings: Implications for California Energy Policy, March 1977.

Kaldor, Mary. The Baroque Arsenal, 1981.

Kennan, George F. American Diplomacy, 1900–1950, 1951.

Kennan, George R. The Nuclear Delusion: Soviet–American Relations In The Atomic Age, 1983.

Killian, James R., Jr. Sputnik, Scientist, and Eisenhower: A Memoir of the First Special Assistant to the President for Science and Technology, 1977.

Kistiakowsky, George B. A Scientist at the White House, 1976.

Kramers, H. A. Collected Scientific Papers, 1956.

Kunetka, James W. City of Fire: Los Alamos and the Birth of the Atomic Age, 1943 to 1945, 1978.

Lang, Daniel. Early Tales of the Atomic Age, 1948.

Levine, Robert A. Still the Arms Debate, 1990.

Lewis, W. B. Electrical Counting, 1943.

Lilienthal, David E. Change, Hope and the Bomb, 1963.

Long, Franklin A. and George W. Rathjens, eds. Arms, Defense Policy, and Arms Control, 1976.

Matematisk–Fysiske. Meddelelser (Dedicated to Professor Niels Bohr on the Occasion of his 60th Birthday), 1945.

McNamara, Robert S. Blundering into Disaster: Surviving the First Century of the Nuclear Age, 1986.

Melman, Seymour. Disarmament: Its Politics and Economics, 1962.

National Academy of Sciences. Committee on International Security and Arms Control. Reykjavik and Beyond: Deep Reductions in Strategic Nuclear Arsenals and the Future Direction of Arms Control, 1988.

National Academy of Sciences. Establishment of a Solar Energy Research Institute, 1975.

National Academy of Sciences. Future of Nuclear Science, 1977.

National Academy of Sciences. Study of Nuclear and Alternative Energy Systems.

Supporting Paper 1: Problems of U.S. Uranium Resources and Supply to the Year 2010, 1978. Supporting Paper 2: Energy Modeling For an Uncertain Future, 1978. Supporting Paper 3: Controlled Nuclear Fusion: Current Research and Potential Progress, 1978. Supporting Paper 4: Geothermal Resources and Technology in the United States, 1979. Supporting Paper 5: Sociopolitical Effects of Energy Use and Policy, 1979. Supporting Paper 6: Domestic Potential of Solar and Other Renewable Energy Sources,, 1979. Supporting Paper 7: Energy Choices in a Democratic Society, 1980. Alternative Energy Demand Futures to 2010, 1979. U.S. Energy Supply Prospects to 2010, 1979. Osgood, William F., and William C. Graustein. Plane and Solid Analytic Geometry, 1922.

Perry, Robert. Development and Commercialization of the Light Water Reactor, 1946–1976, June 1977.

Physical Science And Human Values, 1947.

Radiation Laboratory, MIT. Radiation Laboratory Staff Members, 1940–1945, 1946.

Rasetti, Franco. Elements of Nuclear Physics, 1936.

Readings from Scientific American. Arms Control, 1973.

Report of the New York Herald Tribune Annual Forum. The Struggle for Justice as a World Force, 1946.

Report of the Nuclear Energy Policy Study Group. Nuclear Power Issues and Choices, 1977.

Rich, Daniel L. Physics Laboratory Manual, 1923.

Roberts, John D. The Right Place at the Right Time, 1990.

Rolph, Elizabeth. Regulation of Nuclear Power: The Case of the Light Water Reactor, June 1977.

Rothrock, David A. Elements of Plane and Spherical Trigonometry, 1916.

Sachs, Robert G., ed. National Energy Issues: How We Decide? Plutonium as a Test Case, April 1979.

Science and Technology: A Report to the Congress, 1992,

Segrè, Emilio, ed. Experimental Nuclear Physics. Vols. 1 and 2., 1953.

Stewart, George R. The Year of the Oath, 1950.

Stobaugh, Robert, Daniel Yergin, eds. Energy Future: Report of the Energy Project at the Harvard Business School, 1979.

Szilard, Leo. The Voice of The Dolphins and other Stories, 1961.

The Rand Corporation: The First Fifteen Years, November 1963.

Tolansky, S. Hyperfine Structure in Line Spectra and Nuclear Spin, 1948.

U. S. Department of State. Peace and War: United States Foreign Policy, 1931–1941, 1942.

U.S. Arms Control and Disarmament Agency. Arms Control and Disarmament Agreements, 1982 ed.

U.S. Arms Control and Disarmament Agency. Moving Toward Life in a Nuclear Armed Crowd? April 1976.

U.S. Atomic Energy Commission. Atomic Energy Development: 1947–1948, 1948.

U.S. Congress, Office of Technology Assessment. Comparative Analysis of the 1976 ERDA Plan and Program, May 1976.

Ulam, S. M. Adventures of a Mathematician, 1976.

Uspensky, J. V., and M. A. Heaslet. Elementary Number Theory, 1939.

Washburn, Wilcomb E. The Cosmos Club of Washington, 1978.

Wilson, Jane S. and Charlotte Serber, eds. Standing By and Making Do: Women of Wartime Los Alamos, l988.

Wohlstetter, Albert, Victor Gilinsky, Robert Gillette, Roberta Wohlstetter. Nuclear Policies: Fuel Without the Bomb, 1978.

Wohlstetter, Roberta. Pearl Harbor: Warning and Decision, 1962.

World Power Conference Survey of Energy Resources, 1968.

Wyden, Peter. Day One: Before Hiroshima and After, 1984.

Yagoda, Herman. Radioactive Measurements with Nuclear Emulsions, 1949.

York, Herbert F. Making Weapons, Talking Peace: a Physicist's Odyssey from Hiroshima to Geneva, 1987.

York, Herbert F. The Advisors: Oppenheimer, Teller and the Superbomb, 1976.

Finding Aid for the Robert F. Bacher Papers, 1924-1994
Processed by Kevin C. Knox and Charlotte E. Erwin.
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Describing Archives: A Content Standard
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Repository Details

Part of the California Institute of Technology Archives and Special Collections Repository

1200 East California Blvd.
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