User:Theophilus Reed/sandbox/Columbia Cyclotron

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Columbia Cyclotron
The newly functional cyclotron in 1939, in the basement of Pupin Hall at Columbia University. On the left is John R. Dunning speaking with Enrico Fermi (center) and Dana P. Mitchell, another Columbia/Manhattan Project physicist.
General information
LocationPupin Hall, Columbia University
Town or cityNew York City
Inaugurated1938
Closed1965
Demolished2008
Known forEarly nuclear research leading to the Manhattan Project
UsesParticle accelerator
Notable experimentsFirst fission of uranium in North America, 25 Jan 1939
InventorJohn R. Dunning,
Herbert L. Anderson
Related items UC/Berkeley Cyclotrons,
Cockcroft–Walton multiplier,
Westinghouse Atom Smasher

The Columbia cyclotron, or Columbia atom smasher, was an early particle accelerator housed in the basement of Pupin Hall at Columbia University in New York City. It was associated with early investigations into atomic energy, especially those conducted by Enrico Fermi, Leo Szilárd, Isidor Isaac Rabi, Willis Lamb, Herbert L. Anderson, John R. Dunning, and a number of other pioneering nuclear physicists.

On 25 January 1939, an especially important experiment investigating the nuclear fission of uranium was performed using the apparatus;[1] this effort confirmed the original discovery of fission by the German team of Otto Hahn and Fritz Strassmann from just a few weeks prior.[2][3] This result, along with other research performed over the following months using the Columbia instrument,[4] strongly suggested the possibility of a nuclear chain reaction,[5] which until that time was a wholly theoretical hypothesis. These experiments were critical in efforts to gain scientific and political support for the creation of the Manhattan Project during an early phase of World War II.[6]

Background[edit]

The Columbia apparatus was capable of accelerating protons, deuterons and alpha particles to energies in the range of tens of MeV; it operated from 1938 to 1964. Based upon earlier designs by Ernest Lawrence of the University of California, Berkeley, this cyclotron was built by the pioneering nuclear physicist John R. Dunning,[7] largely from parts salvaged from older industrial facilities.[8][9]

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Federal Telegraph Company (1909-1928) described as Silicon Valley's "first major high-tech company"; 350kw arc transmitter 60 tons [11]

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[19]

p. 129-130 We are familiar with Federal's growth under navy contracts, and with the culmination of their relations in commissioning four 1000-kW generators, two for each end of a radio link between the United States and its expeditionary force in France. Their magnets could deliver 18,000 gauss.. The war ended before the huge antenna towers...could be complete in France. The navy withdrew. leaving France with half a radio station and Federal with four 80-ton magnets... that left Federal with two war-surplus magnets... p. 130. "Lawrence's big magnet, being a piece of high technology, required professional engineering help in its metamorphosis into a tool of science... Cattell wound and insulated the coils at Federal before the magnet went to Pelton for machining... Pelton did an excellent job, the pole faces parallel to four-thousands of an inch, the field homogenous up to 18 kG." [20]


Nuclear research[edit]

Confirmation of Fission Discovery[edit]

The experiment devised aimed at studying the ionization, or electrical pulses, that would be released after uranium atoms had been split. These pulses were to be watched on an oscilloscope, which has been described "as a species of atomic thermometer."! The energy, or pulses, is transformed into lines on an oscilloscope and can thus be observed. On the day of the experiments, Fermi had to go to Washington and Dr. John R. Dunning, with some colleagues, carried out the investigation.

Outside, a cold wind raced through the campus as Dunning and Drs. E. T. Booth and F.G. Slack prepared for the experiment. After laborious efforts in readying the cyclotron, all was ready for the attempt to split the uranium atom. Then the bombardment began, and

Suddenly, huge green lines began to shoot up in the circle of the oscilloscope screen. They leaped high and seemed to jump from the screen and they stunned the scientists. .... He'd [Dunning] never seen anything like it before. He quickly calculated that between 150 and 200 million electron volts were being generated. At that rate one pound of Uranium-235 could yield as much energy as 5 million pounds of coal.

— "Extracts from the Notebooks of John R. Dunning", Press Release, Columbia University (26 January 1964)

Afraid that something might have gone wrong, Dunning carefully checked the cyclotron and other apparatus, but found nothing amiss. He then repeated the experiment many times and by about midnight was convinced that atomic energy could be released.[21]

Decommissioning & Demolition[edit]

Because of the significance of discoveries made using this instrument, the Pupin Physics Laboratories were designated a National Historic Landmark in 1965.[22] Contemporaneously, the instrument was decommissioned, and the core part of the device — the 'double-dee' vacuum chamber where particles were accelerated along with important detector equipment — was donated to the Smithsonian Institution.[8]

In 2007, Columbia University administrators announced plans to junk what remained of the 65-ton apparatus, in order to free-up space for future expansion. Despite vehement protests from faculty, students, and historic preservationists, in 2008, this renowned 'gadget' from the Atomic Age was cut-up and its metal sold for scrap. This was to save an estimated additional expense of approximately $90k to dismantle and store this massive component of the historic instrument.[8][23]

However, it should be noted that the scrapped machinery was largely the circa-1918, war-surplus, former Poulsen-arc transmitter electromagnet, while the much smaller accelerator/detector components that discovered 'new physics' have mostly been preserved at the Smithsonian. A very similar war-surplus, Poulsen-arc electromagnet that was part of Ernest O. Lawrence's 37" cyclotron remains on display on the campus of the University of California, Berkeley.

References[edit]

  1. ^ Anderson, H. L.; Booth, E. T.; Dunning, J. R.; Fermi, E.; Glasoe, G. N.; Slack, F. G. (1 March 1939). "The Fission of Uranium". Physical Review. 55 (5): 511–512.
  2. ^ Hahn, O.; Strassmann, F. (6 January 1939). "Über den Nachweis und das Verhalten der bei der Bestrahlung des Urans mittels Neutronen entstehenden Erdalkalimetalle". Die Naturwissenschaften. 27 (1): 11–15. On the detection and characteristics of the alkaline earth metals formed by irradiation of uranium with neutrons
  3. ^ Meitner, Lise; Frisch, O.R. (11 February 1939). "Disintegration of Uranium by Neutrons: a New Type of Nuclear Reaction". Nature. 143 (3615): 239-40. {{cite journal}}: Unknown parameter |lastauthoramp= ignored (|name-list-style= suggested) (help)
  4. ^ Anderson, H.L.; Fermi, E.; Hanstein, H.B. (15 April 1939). "Production of Neutrons in Uranium Bombarded by Neutrons". Physical Review. 55: 797–98.
  5. ^ Anderson, H.L.; Fermi, E.; Szilárd, Leo (1 August 1939). "Neutron Production and Absorption in Uranium". Physical Review. 56: 284–86.
  6. ^ Hewlett, Robert G.; Anderson, Jr., Oscar E. (1962). The New World, 1939-1946 (PDF). History of the United States Atomic Energy Commission. Vol. 1. Pennsylvania State University Press. pp. 9–26. Retrieved 3 January 2020.
  7. ^ "Speed Record Set by Atom-Smasher: Columbia Cyclotron Throws Protons With the Highest Energy Yet Obtained". New York Times. January 24, 1939. Retrieved January 3, 2020.
  8. ^ a b c Broad, William J. (December 20, 2007). "Columbia's Historic Atom Smasher Is Now Destined for the Junk Heap". New York Times. Retrieved 5 January 2020.
  9. ^ Anderson, Herbert L. (1989). "John Ray Dunning". Biographical Memoirs. Vol. 58. Washington DC: National Academies Press. p. 163-188. doi:10.17226/1645. ISBN 978-0-309-03938-3.
  10. ^ Mann, F.J. (December 1946). "Federal Telephone and Radio Corporation. A Historical Review 1909-1946". Electrical Communication. 23: 377–405.
  11. ^ Adams, Stephen B. (Summer 2017). "Arc of Empire: The Federal Telegraph Company, the U.S. Navy, and the Beginnings of Silicon Valley". Business History Review. 91 (2): 329–359. Retrieved 6 January 2020.
  12. ^ Elwell, Cyril Frank (1923). The Poulsen Arc Generator. Van Nostrand Co. ASIN B0037F5DWK.
  13. ^ Fuller, Leonard (May 29, 1976). "Oral History: Leonard Fuller". Engineering and Technology History Wiki. ETHW Partnership. Retrieved 8 January 2020. interview by George T. Royden, IEEE History Center
  14. ^ Hawkins, Jim (19 October 2001). "The Birth of NSS Annapolis". Jim Hawkins' Radio and Broadcast Technology Page. Retrieved 8 January 2020. These photos were scanned from negatives (c. 1918) obtained by purchase through an auction. The source of the photographs are unknown. The descriptions on the photos are quoted from the writing on the negatives.
  15. ^ Callaway, Ed. "The Arc Radio Transmitter, 1880-1920". Sunrise Micro Devices. Retrieved 8 January 2020. Navy's Annapolis arc transmitter sent to Columbia University, used to confirm (in 1939) the discovery of atomic fission
  16. ^ Anderson, Herbert L. (1984). "The First Chain Reaction" (PDF). In Robert J. Sachs (ed.). The Nuclear Chain Reaction — Forty Years Later, Proceedings of a University of Chicago commemorative symposium. University of Chicago. p. 10-39. Retrieved 8 January 2020.
  17. ^ "Columbia University Cyclotron (John R. Dunning, 1939)". National Museum of American History, Behring Center. Smithsonian Institution. Retrieved 9 January 2020. Object ID No. 1978.1074.01, Currently not on view
  18. ^ "Theory of Operation". Koeth Cyclotron. Rutgers University. Retrieved 9 January 2020. adapted from Tipler's Physics for Scientists and Engineers, Vol. 2
  19. ^ Darling, Lloyd E. (December 1919). Kaempffert, Waldemar (ed.). "For the Radio Experimenter — Working with Artificial Lightning". Popular Science. Vol. 95, no. 5. New York City. Retrieved 9 January 2020. The proper insulation of such large machines as the 500 kW arc transmitter installed at Annapolis, Maryland in 1918, and the 1000 kW machine set up at the Lafayette station near Bordeaux, France, by the Navy Department, offered difficulties.
  20. ^ Heilbron, J.L.; Seidel, Robert W. (1989). Lawrence and his Laboratory, A History of the Lawrence Berkeley Laboratory. Vol. 1. Berkeley: University of California Press. p. 134. ISBN 0-520-06426-7. Retrieved 9 January 2020. In 1932 New York University inquired into the fate of the 500-kW arcs at Annapolis and reserved one at its decommissioning in June 1934...In 1934, Cornell tried to obtain one of the decommissioned Annapolis magnets. Columbia too was interested; the navy had but one magnet to give, the one that NYU had reserved but had since relinquished; Columbia, which had been frustrated by the navy's sale as scrap of another Poulsen magnet it had coveted, won the prize.
  21. ^ McKithan, Cecil (March 1978). National Register of Historic Places Inventory (Report). U.S. National Park Service. Retrieved 5 January 2020. {{cite report}}: Cite has empty unknown parameter: |authors= (help)
  22. ^ "Pupin Physics Laboratory, Columbia University". National Historic Landmarks Program (archived). National Park Service. 21 December 1965. Retrieved 3 January 2020. Initial experiments on the nuclear fission of uranium were conducted here by Enrico Fermi. The uranium atom was split here on January 25, 1939.
  23. ^ Linthicum, Kate (31 March 2008). "Cyclotron's Last Stand". The New Yorker. Retrieved 3 January 2020.

External links[edit]


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