Physics History Network
Over 1000 biographies of physicists and histories of institutions with information pertaining to their lives, careers, and research.
Tip: Search within this page by using Ctrl + F or ⌘ + F
Search Our Catalogs
Archives BooksCollections
Emilio Segré Visual Archives Digital Collections Oral Histories Archival Finding Aids Physics History Network Member Society Portals Ethical Cataloging StatementPreservation and Support
Donating Materials Suggest a Book Purchase Saving Archival Collections Grants to Archives Documentation Projects History NewslettersCenter for History of Physics
Scholarship & OutreachThe Manhattan Project and predecessor organizations
For additional information on research and advocacy leading up to the Manhattan Project, see the Nuclear Fission, 1938–1942 topic guide.
Contents
Advisory Committee on Uranium, October 1939-1940
Committee/Section on Uranium, June 1940-January 1942
National Academy of Sciences review committee, April-November 1941
OSRD Section S-1, January-June 1942
Manhattan Project Timeline, 1942-43
Chicago Metallurgical Laboratory, 1942
Chicago Metallurgical Project, 1943-1946
Project Y: Los Alamos Laboratory
Los Alamos Organization, March 1943-August 1944
Los Alamos Organization, August 1944-August 1945
Other Los Alamos Staff in PHN, 1943-1946
Resources
The official history, Richard G. Hewlett and Oscar E. Anderson, Jr., A History of the United States Atomic Energy Commission, Volume I: The New World, 1939-1946 (University Park, PA: Pennsylvania State University Press, 1962) is a detailed introduction to the various technical and administrative facets of the Manhattan Project.
Also see the well developed history pages at the Los Alamos National Laboratory website, including a large collection of wartime staff badge photos.
Advisory Committee on Uranium, October 1939-June 1940
This ad hoc committee was established in October 1939 by President Franklin Roosevelt to monitor and advise the government and military with respect to research on nuclear fission.
Chairman:
Colonel Keith Adamson, United States Army
Commander Gilbert Hoover, United States Navy
In June 1940 a technical subcommittee was added:
Committee/Section on Uranium, June 1940-January 1942
In June 1940 President Roosevelt created the National Defense Research Committee (NDRC) to be chaired by Vannevar Bush. The Advisory Committee on Uranium was absorbed into the NDRC, reorganized, and renamed. Because the NDRC was an explicitly civilian organization, the military members of the committee were dropped. In June 1941 President Roosevelt created the Office of Scientific Research and Development (OSRD) to be directed by Bush. James Conant became head of the NDRC, which was now within the OSRD, and the committee became one fo a number of "sections" under the NDRC.
Chairman:
Lyman Briggs (June 1940-January 1942)
Vice Chairman:
George Pegram (June 1940-January 1942)
Ross Gunn (June 1940-September 1941)
Merle Tuve (June 1940-September 1941)
Harold Urey (June 1940-January 1942)
Jesse Beams (June 1940-January 1942)
Gregory Breit (September 1941-January 1942)
Samuel Allison (September 1941-January 1942)
Edward Condon (September 1941-January 1942)
Henry Smyth (September 1941-January 1942)
Lloyd Smith (September 1941-January 1942)
National Academy of Sciences review committee, April-November 1941
In April 1941 Vannevar Bush asked National Academy of Sciences president Frank Jewett to create a committee to review progress in fission research and advise regarding future work.
Chairman:
Arthur Compton (April to November)
Ernest Lawrence (April to November)
John Van Vleck (April to November)
William Coolidge (April to November)
Oliver Buckley (June to November)
L. Warrington Chubb (June to November)
Warren Lewis (September to November)
George Kistiakowsky (September to November)
Robert Mulliken (September to November)
OSRD Section S-1, January-June 1942
In January 1942, Vannevar Bush reorganized the Section on Uranium, renamed Section "S-1", into a vigorous program to drive toward the development of an atomic weapon. The section was removed from the NDRC and made an independent organization within the OSRD. In June 1942, the leaders of Section S-1 became the S-1 "executive committee" responsible for overseeing the relationship between the OSRD and what was increasingly an army-directed project.
Section S-1 Chariman:
NDRC Chairman:
Section S-1 Planning Board Chief:
Eger Murphree
Secton S-1 Program Chief:
Section S-1 Program Chief:
Section S-1 Project Chief:
Manhattan Project Timeline, 1942-1943
January 1942
Arthur Compton decides to consolidate research on slow-neutron chain reaction into a new "Metallurgical Laboratory" to be located on the University of Chicago campus.
March 1942
The OSRD initiates contact with the U. S. Army to turn over construction of bomb production facilities to their authority.
June 1942
J. Robert Oppenheimer is placed in charge of fast-neutron research, replacing Gregory Breit. The U. S. Army places Col. James Marshall of the Army Corps of Engineers in charge of constructing production facilities for bomb materials. The Stone and Webster Engineering Corporation is chose as primary contractor for the project, and the Tennessee River Valley is first considered a strong candidate for a production plant. The Argonne Forest Preserve outside Chicago is slated for the construction of a pilot plant for plutonium production.
August 1942
The Manhattan Engineer District is established with the U. S. Army Corps of Engineers to oversee the bomb development project.
September 1942
On September 17, Col. Leslie Groves of the U. S. Army Corps of Engineers is placed in charge of the Manhattan Project; Marshall remains the district engineer. On the 23rd, following Groves' promotion to Brigadier General, the posting is made official. Shortly thereafter Groves secures a site at Oak Ridge, Tennessee, near Knoxville, as the site for bomb material production and places DuPont in charge of construction of a plutonium separation facility ther ein view of doubts about the capabilities of Stone and Webster. DuPont agrees on October 3. It is also decided that the pilot plutonium production plant will be located at Oak Ridge rather than Argonne, which instead will house the Chicago Metallurgical Laboratory's experimental reactor.
November 1942
Groves and Oppenheimer select a boys' school on a mesa near Los Alamos, New Mexico as the site for a new bomb development laboratory.
December 1942
On December 2, the experimental pile at the Chicago Metallurgical Laboratory produces a self-sustaining chain reaction.
January 1943
Hanford, on the Columbia River near Richmond, Washington, is chose as the site of the Manhattan Project's full-scale plutonium production facility.
Resources: See the U. S. Department of Energy page on Hanford history. For much further detail, see John M. Findlay and Bruce Hevly, Atomic Frontier Days: Hanford and the American West (Seattle: University of Washington Press, 2011).
February 1943
The experimental pile at the University of Chicago, called CP-1, is shut down and removed to the facility at the Argonne Forest Preserve outside Chicago. The reconstructed and expanded experimental pile, CP-2, goes into operation there in March. On February 25, NDRC Chairman James Conant and Vice Chairman Richard Tolman are officially appointed scientific advisers to Groves, though they had consulted with him since the previous year. They, rather than the S-1 Executive Committee, become Groves' primary points of contact with the OSRD as the OSRD transfers research and development on all basic production processes over to the army.
March 1943
J. Robert Oppenheimer and support staff arrive in New Mexico, working out of Santa Fe as construction of the Los Alamos site continues.
Chicago Metallurgical Laboratory, 1942
The Chicago Metallurgical Laboratory was officially established in January 1942 by Section S-1 Program Chief Arthur Compton, and was built up over the spring and summer. Laboratory administration was initially loose, but was steadily tightened over the course of the year, with some changes in titles and responsibilities. The below-listed names are mainly laboratory leadership, but some support staff, marked with a *, are also mentioned because they are in PHN.
Leadership
Project Leader: Arthur Compton
Administrative Assistant to the Project Leader: Norman Hilberry
Administrative Office: Richard Doan
(initally Laboratory Director)
Fast-Neutron Research Coordinator: Gregory Breit
(also Information Chief; resigns May 18)
Physics Group
Leader: Enrico Fermi
(initially Laboratory Research Coordinator)
*Harold Agnew (a research assistant under Anderson)
Leo Szilard (initally uranium supply coordinator)
John Manley (experimental assistant to J. R. Oppenheimer)
George Monk
Arthur Snell
Joyce C. Stearns
Martin Whitaker
Volney Wilson
Frank Foote (MIT)
John Marshall (MIT)
Theoretical Goup
Leader: Eugene Wigner
(Initially Laboratory Theoretical Chief)
John Wheeler (also Library Leader)
Francis Friedman
Emil Konopinski
Nicholas Metropolis
Forest Murray
Leo Ohlinger
Gilbert Plass
Gale Young
Hans Bethe (Boston)
J. Robert Oppenheimer (Berkeley)
(Fast-Neutron Project Leader from June)
Robert Serber (Berkeley)
Chemical Group
Leader: Samuel Allison
(initally Laboratory Experimental Chief)
George Boyd
Milton Burton
Charles Coryell
*Isadore Perlman (a research assistant under Seaborg)
Frank Spedding
Health Group Leader
R. S. Stone
Property Leader
A. M. MacMahon
Procurement Leader
C. A. Trejillus
Chief Engineer
T. V. Moore
Chicago Metallurgical Project, 1943-1946
In 1943, following the successful completion of an experimental reactor pile, laboratory staff and organization changed markedly as staff moved to the experimental reactor at the nearby Argonne Forest Preserve, to the pilot plutonium production plant and separation facility at Clinton Engineer Works near Oak Ridge, Tennessee, to the Hanford full-scale plutonium production and separation facility in Washington State, and to the new bomb design laboratory at Los Alamos, New Mexico. The below-listed personnel do not comprise a full outline of the organization of the Chicago-area work in this period. However, all personnel who appear in PHN are included here.
After the war, the Argonne laboratory was retained by the new Atomic Energy Commission, and eventually became the Argonne National Laboratory.
Project Director:
Chicago Metallurgical Laboratory Directors:
Samuel Allison (June 1943–November 1944)
Joyce Stearns (November 1944–July 1945)
Farrington Daniels (July 1945–May 1946)
Argonne Laboratory Directors:
Enrico Fermi (1943–1944)
Walter Zinn (1944–1946)
Other Personnel in PHN:
James Franck (1942–1945)
Director, Chemistry Division (1942–1943)
Associate Project Director (1943–1944)
Consultant (1944–1945)
Norman Hilberry (1942–1946)
Assistant Project Director (1943–1946)
Acting Director, Physics Division (1944)
Glenn Seaborg (1942-1946)
Chief, Plutonium Chemistry Section (1943-1946)
Henry Smyth (1943-1945)
Associate Laboratory Director (1943-1944)
Consultant (1944-1945)
Arthur Dempster (1943-1946)
Director, Physics and Metallurgy Division (1945-1946)
Farrington Daniels (1944-1946)
Assistant Director, Chemistry Division (1944-1945)
Laboratory Director (1945-1946)
Herbert Anderson (1942-1944)
Eugene Wigner (1942-1945)
Alvin Weinberg (1942-1945)
Leo Szilard (1942-1946)
Julian Schwinger (1943-1943)
Luis Alvarez (1943-1944)
Philip Morrison (1943-1944)
Marvin Goldberger (Army SED, 1943-1945)
Anthony Turkevich (1943-1945)
John Simpson, Jr. (1943-1946)
Leonard Rieser (1944-1944)
Project Y: Los Alamos Laboratory
Research and development surrounding the design of the atomic bomb took place at a laboratory atop a mesa near Los Alamos, New Mexico. After the war the laboratory was retained by the new Atomic Energy Commission primarily as a laboratory for the development of nuclear weaponry. It was renamed the Los Alamos Scientific Laboratory, before being renamed Los Alamos National Laboratory in 1981. The key sources on the wartime history are:
David Hawkins, Project Y: The Los Alamos Story, Part I: Toward Trinity (Los Angeles: Tomash, 1983), originally published in 1961.
Lillian Hoddeson, Paul W. Henriksen, Roger A. Meade, and Catherine Westfall, et al., Critical Assembly: A Technical History of Los Alamos during the Oppenheimer Years, 1943-1945 (New York: Cambridge University Press, 1993)
Los Alamos Organization, March 1943-August 1944
Laboratory Director
Theoretical Division (formally organized in March 1944)
Division Leader: Hans Bethe
Group T-1 (Hydrodynamics of Implosion and Super*)
Leader: Edward Teller (March-June 1944)
Group T-1 (Hydrodynamics of Implosion)
Leader: Rudolf Peierls (from June 1944)
Group T-2 (Diffusion Theory, IBM Calculations, and Experiments)
Leader: Robert Serber
Group T-3 (Experiments, Efficiency Calculations, and Radiation Hydrodynamics)
Leader: Victor Weisskopf
Group T-4 (Diffusion Problems)
Leader: Richard Feynman
Group T-5 (Computations)
Leader: Donald Flanders
*In June 1944 Teller established theoretical work on the "super" fusion weapon as an independent group.
Experimental Physics Division (organized March 1943)
Division Leader: Robert Bacher
Group P-1 (Cyclotron)
Leader: Robert R. Wilson
Group P-2 (Electrostatic Generator)
Leader: John H. Williams
Group P-3 (D-D Source)
Leader: John Manley
Group P-4 (Electronics)
Leader: Darol Froman
Group P-5 (Radioativity)
Leader: Emilio Segrè
Group P-6 (Detectors), established September 1943
Leader: Bruno Rossi
Group P-7 (Water Boiler), established August 1943
Leader: Donald Kerst
In July 1943 a group for improving counters was set up under Hans Staub; in August 1943 a group for improving electronic techniques was set up under Bruno Rossi; in September these were consolidated into Group P-6.
Ordnance and Engineering Division (organized June 1943)
Division Leader: Cpt. William Parsons, United States Navy
Deputy Division Leaders (from early 1944):
Edwin McMillan (Gun Program)
George Kistiakowsky (Implosion Program)
Group E-1 (Proving Ground)
Leader: Edwin McMillan
Group E-2 (Instrumentation)
Leader: Kenneth Bainbridge (June 1943-early 1944)
Leader: Lyman Parratt (1944)
Group E-3 (Fuse Development)
Leader: Robert Brode
Group E-4 (Projectile, Target, and Source)
Leader: Charles Critchfield
Group E-5 (Implosion Experimentation)
Leader: Seth Neddermeyer (June 1943-June 1944)
Acting Leader: George Kistiakowsky (June-August 1944)
Group E-6 (Engineering)
Chief Engineer: George Chadwick (prospective, June-September 1943)
Chief Engineer: J. L. Hittell (September-December 1943)
Chief Engineer: P. Esterline (December 1943-April 1944)
Chief Engineer: R. Cornog (April-May 1944)
Chief Engineer: L. D. Bonbrake (May-August 1944)
Group E-7 (Delivery), established fall 1943
Leader: Norman Ramsey
Group E-8 (Interior Ballistics), established fall 1943
Leader Joseph Hirschfelder
Group E-9 (High-Explosive Assemblies), established early 1944
Leader: Kenneth Bainbridge
Group E-10 (Maintenance and Construction for Implosion Project & S-Site Operation), established June 1944
Leader: Maj. W. A. Stevens
Group E-11 (RaLa Tests and Electric Detonates), established June 1944
Leader: Luis Alvarez
Chemistry and Metallurgy Division (May 1943 to April 1944)
Acting Division Leader: Joseph Kennedy
Purification Group, Leader: Clifford Garner
Radiochemistry Group, Leader: Richard Dodson
Analysis Group, Leader: Samuel Weissman
Metallurgy Group, Leader: Cyril Smith
Chemistry and Metallurgy Division (April 1944 to August 1944)
Division Leader: Joseph Kennedy
Associate Division Leader (Metallurgy): Cyril Smith
Group CM-1 (Health and Safety, Special Services)
Leader: R. H. Dunlap
Group CM-2 (Heat Treating and Metallography)
Leader: F. Stroke
Group CM-3 (Gas Tamper and Gas Liquefaction)
Leader: Earl Long
Group CM-4 (Radiochemistry)
Leader: Richard Dodson
Group CM-5 (Uranium and Plutonium Purification)
Leader: Clifford Garner
Group CM-6 (High-Vacuum Research)
Leader: Samuel Weissman
Group CM-7 (Miscellaneous Metallurgy)
Leader: Claire Balke
Group CM-8 (Uranium and Plutonium Metallurgy)
Leader: Eric Jette
Group CM-9 (Analysis)
Leader H. A. Potratz
Group CM-10 (Recovery)
Leader: Robert Duffield
Group CM-11 (Uranium Metallurgy), established June 1944
Leader: Alan Seybolt
Los Alamos Organization, August 1944-August 1945
In August 1944, the Los Alamos Laboratory was substantially reorganized on account of the infeasibility of a "gun" design for a plutonium bomb on account of the rate of spontaneous fission in that element. The new laboratory organization was geared toward achieving rapid progress with the implosion bomb design.
Laboratory Director
Associate Laboratory Director
Associate Laboratory Director
Cpt. William Parson, United States Navy
Theoretical Division
Division Leader: Hans Bethe
Group T-1 (Implosion Dynamics)
Leader: Rudolf Peierls
Group T-2 (Diffusion Theory)
Leader: Robert Serber
Group T-3 (Efficiency Theory)
Leader: Victor Weisskopf
Group T-4 (Diffusion Problems)
Leader: Richard Feynman
Group T-5 (Computations)
Leader: Donald Flanders
Group T-6 (IBM Computations), established September 1944
Leaders: Stanley Frankel and Eldred Nelson
Group T-7 (Damage), established November 1944
Leader: Joseph Hirschfelder
Group T-8 (Composite Weapon), established May 1945
Leader: George Placzek
Research Division
Division Leader: Robert R. Wilson
Group R-1 (Cyclotron)
Leader: Robert R. Wilson
Group R-2 (Electrostatic Generator)
Leader: John H. Williams
Group R-3 (D-D)
Leader: John Manley
Group R-4 (Radioactivity)
Leader: Emilio Segrè
F Division
F Division considered issues outside the main project.
Division Leader: Enrico Fermi
Group F-1 (Super and General Theory)
Leader: Edward Teller
Group F-2 (Water Boiler)
Leader: L. D. P. King
Group F-3 (Super Experimentation)
Leader: Egon Bretscher
Group F-4 (Fission Studies)
Leader: Herbert Anderson
Ordnance Divsion
Division Leader:
Group O-1 (Gun)
Leader: Francis Birch
Group O-2 (Delivery)
Leader: Norman Ramsey
Group O-3 (Fuse Development)
Leader Robert Brode
Group O-4 (Engineering)
Leader: George Galloway
Group O-5 (Calculations)
Leader: Joseph Hirschfelder
Group O-6 (Water Delivery and Exterior Ballistics)
Leader: Maurice Shapiro
Group O-7 (Procurement)
Leader: Lt. Col. R. W. Lockridge
Weapon Physics Division
Division Leader: Robert Bacher
Group G-1 (Critical Assemblies)
Leader: Otto Frisch
Group G-2 (The X-Ray Method)
Leader: Lyman Parratt
Group G-3 (The Magnetic Method)
Leader: Edwin McMillan
Group G-4 (Electronics)
Leader: William Higinbotham
Group G-5 (The Betatron Method)
Leader: Seth Neddermeyer
Group G-6 (The RaLa Method)
Leader: Bruno Rossi
Group G-7 (Electric Detonators)
Leader: Luis Alvarez
Group G-8 (The Electric Method)
Leader: Darol Froman
Group G-10 (Initiator Group)
Leader: Charles Critchfield
Group G-11 (Optics)
Leader: Julian Mack
Explosives Division
Division Leader: George Kistiakowsky
Group X-1 (Implosion Research)
Leader: Commander Norris Bradbury
Group X-1A (Photography with Flash X-Rays), dissolved May 1945
Leader: Kenneth Greisen
Group X-1B (Terminal Observations)
Leader: Henry Linschitz
Group X-1C (Flash Photography)
Leader: Walter Koski
Group X-1D (Rotating Prism Camera)
Leader: Joseph Hoffman
Group X-1E (Charge Inspection)
Leader: Gerold Tenney
Group X-2 (Development, Engineering, and Tests), dissolved March 1945
Leader: Kenneth Bainbridge
Group X-2A (Engineering), renamed X-2 March 1945
Leader: Robert Henderson
Group X-2B (High Explosives), dissolved March 1945
Leader: Lt. W. F. Schaffer
Group X-2C (Test Measurements), dissolved March 1945
Leader: Lewis Fussell Jr.
Group X-3 (Explosives Development and Production)
Leader: Cpt. Jerome Ackerman
Group X-3A (Experimental Section)
Leader: Lt. J. D. Hopper
Group X-3B (Special Research Problems), established November 1944
Leader: David Gurinsky
Group X-4 (Model Design, Engineering Service, and Consulting), established October 1944
Leader: Earl Long
Group X-5 (Detonating Circuit), established March 1945
Leader: Lewis Fussell Jr.
Group X-6 (Assembly and Assembly Tests), established March 1945
Leader: Commander Norris Bradbury
Group X-7 (Detonator Developments), established May 1945
Leader: Kenneth Greisen
Chemistry and Metallurgy Division
Division Leader: Joseph Kennedy
Associate Division Leader (Metallurgy): Cyril Smith
Group CM-1 (Service Group)
Leader: R. H. Dunlap
Group CM-2 (Heat Treatment and Metallography)
Leader: F. Stroke
Group CM-4 (Radiochemistry)
Leader: Lindsay Helmholtz
Group CM-5 (Plutonium Purification)
Leader: Clifford Garner
Group CM-6 (High-Vacuum Research)
Leader: Samuel Weissman
Group CM-7 (Miscellaneous Metallurgy)
Leader: Alan Seybolt
Group CM-8 (Plutonium Metallurgy)
Leader: Eric Jette
Group CM-9 (Analysis)
Leader: H. A. Potratz
Group CM-11 (Uranium Metallurgy)
Leader: S. Marshall
Group CM-12 (Health)
Leader: W. H. Hinch
Group CM-13 (DP Site)
Leader: Joseph Burke
Group CM-14 (RaLa Chemistry)
Leader: Gerhardt Friedlander
Group CM-15 (Polonium)
Leader: Iral Johns
Group CM-16 (Uranium Chemistry)
Leader: Edward Richers
Project Trinity, established March 1945
Project Trinity prepared the test of the plutonium bomb design.
Head: Kenneth Bainbridge
Consultant (Structures): Roy Carlson
Consultant (Meteorology): P. E. Church
Consultant (Physics): Enrico Fermi
Consultant (Damage): Jospeh Hirschfelder
Consultant (Safety): S. Kershaw
Consultant (Earth Shock): L. Don Leet
Consultant (Blast and Shock): William Penney
Consultant (Physics): Victor Weisskopf
Consultant: Philip Moon
Assembly: Commander Norris Bradbury and George Kistiakowsky
Group TR-1 (Services)
Leader: John H. Williams
Group TR-2 (Blast and Shock)
Leader: John Manley
Group TR-3 (Measurements), renamed Physics
Leader: Robert R. Wilson
Group TR-4 (Meteorology)
Leader: Jack Hubbard
Group TR-5 (Spectrographic and Photographic Measurements
Leader: Julian Mack
Group TR-6 (Airborne Measurements), renamed Air Blast
Leader: Bernard Waldman
Group TR-7 (Medical)
Leader: Dr. Louis Hempelmann
Project Alberta, established March 1945
Project Alberta prepared for combate use of atomic weapons.
Key personnel on Tinian Island
Officer-in-Charge: Cpt. William Parson, United States Navy
Scientific and Technical Deputy: Norman Ramsey
Operations Officer and Military Alternate: Commander Frederick Ashworth
Fat Man Assembly Team Leader: Roger Warner
Little Boy Assembly Team Leader: Francis Birch
Fusing Team Leader: Edward Doll
Electrical Detonator Team Leader: Lt. Commander E. Stevenson
Pit Team Leaders: Philip Morrison and Charles Baker
Observation Team Leaders: Luis Alvarez and Bernard Waldman
Aircraft Ordnance Team Leader: Sheldon Dike
Special Consultants:
Robert Serber
William Penney
Cpt. James Nolan
Other Los Alamos Staff in PHN, 1943-1946
Felix Bloch (1943)
Boyce McDaniel (1943-1945)
Wolfgang Panofsky (consultant, 1943-1945)
Harold Agnew (1943-1946)
Henry Barschall (1943-1946)
Owen Chamberlain (1943-1946)
Robert Christy (1943-1946)
Edward Creutz (1943-1946)
Robert Duffield (1943-1946)
Kenneth Case (1944-1945)
Samuel Allison (1944-1946)
Herbert Anderson (1944-1946)
Benjamin Bederson (Army SED, 1944-1946)
Martin Deutsch (1944-1946)
Val Fitch (Army SED, 1944-1946)
Roy Glauber (1944-1946)
Robert Marshak (1944-1946)
Maria Goeppert Mayer (1945)
Jerrold Zacharias (1945)
Dale Corson (1945-1946)
Leonard Rieser (1945-1946)
Leonard Schiff (1945-1946)
Anthony Turkevich (1945-1946)
Jerome Wiesner (1945-1946)