Editing Calutron (section)

== Postwar years ==

[[File:Calutron silver coils before being returned to treasury (Y-12 126949).jpg|thumb|Calutron silver coils prior to their being melted down and returned to the US Treasury.]]

The workforce at Y-12 dropped from a wartime peak of 22,482 on 21 August 1945 to less than 1,700 in 1949.<ref name="Dedication, Innovation, and Courage" /> All the calutrons were removed and dismantled, except for the XAX and XBX training tracks in Building 9731, and the Beta 3 racetracks in Building 9204–3.<ref>{{cite web |url=https://www.y12.doe.gov/sites/default/files/history/pdf/articles/07-10-18.pdf |title=9731: First building completed at Y-12 |publisher=[[United States Department of Energy|Department of Energy]] |access-date=5 September 2015 |url-status=dead |archive-url=https://web.archive.org/web/20160304113538/https://www.y12.doe.gov/sites/default/files/history/pdf/articles/07-10-18.pdf |archive-date=4 March 2016  }}</ref><ref name="Beta 3">{{cite web |url=https://www.y12.doe.gov/sites/default/files/history/pdf/articles/09-01-22.pdf |title=Beta 3 at Y-12 |publisher=[[United States Department of Energy|Department of Energy]] |year=2009 |access-date=5 September 2015 |url-status=dead |archive-url=https://web.archive.org/web/20160304085441/https://www.y12.doe.gov/sites/default/files/history/pdf/articles/09-01-22.pdf |archive-date=4 March 2016  }}</ref> In 1947, [[Eugene Wigner]], the director of the [[Oak Ridge National Laboratory]] (ORNL), asked the [[United States Atomic Energy Commission|Atomic Energy Commission]] for permission to use the Beta calutrons to produce isotopes for physics experiments. Permission was granted, and a wide range of isotopes was produced. [[Lithium-6]] from the Beta calutrons was used for research into [[thermonuclear weapons]]. Many other isotopes were used for peaceful scientific and medical purposes.{{sfn|Larson|2003|p=108}} The Beta 3 racetracks were transferred to the ORNL in March 1950.<ref name="Beta 3" /> By the mid-1950s, the Beta calutrons had produced quantities of all the naturally occurring stable isotopes except those of [[osmium]], which had to wait until April 1960.{{sfn|Love|1973|p=347}} The calutrons continued to produce isotopes until 1998.<ref>{{cite book|title = Stable isotope separation in calutrons – Forty years of production and distribution|last1 = Bell|first1 = W.A.|publisher = Oak Ridge National Laboratory|year = 1987|url = http://www.ornl.gov/info/reports/1987/3445605813126.pdf|last2 = Tracy|first2 = J.G.|volume = ORNL TM 10356|url-status=dead|archive-url = https://web.archive.org/web/20120927150051/http://www.ornl.gov/info/reports/1987/3445605813126.pdf|archive-date = 27 September 2012|df = dmy-all}}</ref> {{As of|2015}}, they are still on standby.<ref>{{cite news |url=http://oakridgetoday.com/2015/03/27/planning-for-national-park-park-service-tours-jackson-square-k-25-ornl-y-12/ |title=Planning for national park, federal officials tour Jackson Square, K-25, ORNL, Y-12 |newspaper=Oak Ridge |date=27 March 2015 |first=John |last=Huotari }}</ref>