Emilio Segrè Visual Archives

More than 30,000 photos of scientists and their work

Attention ESVA patrons:

The Emilio Segrè Visual Archives’ site is moving soon and adopting an open access approach to digital image sharing. Once we have transitioned to the new site in 2021, we will no longer charge for our high-resolution digital images or usage fees (note that we do not hold copyright to all the images in our collections and you will still need to obtain permission for those which we do not own).

If you are working on a long-term project, we advise you to wait until the migration is complete so that you may obtain our copies for free. If you cannot wait, email us at nbl [at] aip.org and we will do what we can to assist you. We will not be offering refunds for past purchases.

For more information, please visit our FAQ page on the Ex Libris Universum blog. 

Cooksey Donald F1

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Cooksey Donald F1

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We charge a usage fee per photo if the photo is published, reproduced in a product or publicly exhibited. This is not a license in the legal sense. As a non-profit institution, we do not make any money providing these photographs. It is only by assessing usage fees that we are able to cover the cost of providing publication quality copies of our photos, preserving the photograph collection according to archival standards, and providing access to the collection by maintaining an online image database. The copyright holder may charge a fee in addition to our service fee.

Images are for use in educational projects only and must be used in a respectful manner.

Image title: 
Donald Cooksey and G. K. Green view the 60-inch cyclotron at the University of California Lawrence Radiation Laboratory, Berkeley
Credit line: 
Lawrence Berkeley National Laboratory, courtesy AIP Emilio Segrè Visual Archives, Fermi Film Collection

(L-R): Donald Cooksey and G. K. Green view the 60-inch cyclotron at the University of California Lawrence Radiation Laboratory, Berkeley. The machine was the most powerful atom-smasher in the world at the time. It had started operating early in the year. During the period of the photograph Dr. Edwin M. McMillan was doing the work which led a year later to the discovery of neptunium (element 93) a year later. The instrument was used later by Dr. Glenn T. Seaborg and his colleagues for the discovery of element 94 (plutonium) early in 1941. Subsequently, other transuranium elements were discovered with the machine, as well as many radioisotopes, including carbon-14. For their work, Drs. Seaborg and McMillan shared the Nobel Prize in 1951. The machine was used for the "long bombardments" which produced the first weighable and visible quantities of plutonium, which was used at Chicago by Seaborg and his colleagues to work out the method for separating plutonium on an industrial scale at the Hanford, Washington, plutonium production plant. The historic instrument was dismantled at the end of June, 1962, and the magnet sent to the Davis campus of the University of California, to be converted into a more modern machine.

Photo date: 
August, 1939
Original format: 
2 photographic print (black and white; 10 x 6.75 inches)
Cooksey, Donald, 1892-1977
Green, G. Kenneth