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Old page wikitext, before the edit (old_wikitext) | '{{short description|Subcritical mass of plutonium used in the Manhattan Project}}
{{good article}}
[[File:Partially-reflected-plutonium-sphere.jpeg|300px|thumb|alt=A square base of metal blocks, with a smaller square of metal on the top in the centre, a metal ball (the "core") contained in its centre. A ruler along one side of the base shows it is roughly {{convert|10.5|in}} square.|A re-creation of the experiment involved in the 1945 incident. The sphere of plutonium is surrounded by [[neutron reflector|neutron-reflecting]] [[tungsten carbide]] blocks.]]
The '''demon core''' was a spherical {{convert|6.2|kg|lb|0|adj=on}} [[critical mass|subcritical mass]] of [[plutonium]] {{convert|89|mm|in}} in diameter, manufactured during [[World War II]] by the United States [[Timeline of nuclear weapons development|nuclear weapon development]] effort, the [[Manhattan Project]], as a fissile [[Pit (nuclear weapon)|core]] for an early [[atomic bomb]]. It was involved in two [[criticality accident]]s, on August 21, 1945, and May 21, 1946.
The core was intended for use in a possible third nuclear weapon to be [[Atomic bombings of Hiroshima and Nagasaki|dropped on Japan]], but when [[Japan's surrender]] made this unnecessary, it was repurposed for testing. It was designed with a small safety margin to ensure a successful [[Nuclear explosion|explosion]] of the bomb. The device briefly went [[supercritical mass|supercritical]] when it was accidentally placed in supercritical configurations during two separate experiments intended to guarantee the core was close to the critical point. The incidents happened at the [[Los Alamos Laboratory]], resulting in the acute [[radiation poisoning]] and subsequent deaths of scientists [[Harry Daghlian]] and [[Louis Slotin]], respectively. After these incidents the spherical plutonium core was referred to as the "demon core".
==Manufacturing and early history==
The demon [[Pit (nuclear weapon)|core]] (like the second core used in the [[Atomic bombings of Hiroshima and Nagasaki#Nagasaki|bombing of Nagasaki]]) was, when assembled, a solid {{convert|6.2|kg|lb|0|adj=on}} sphere measuring {{convert|89|mm|in}} in diameter. It consisted of three parts: two [[Plutonium–gallium alloy|plutonium-gallium]] hemispheres and a ring, designed to keep [[neutron flux]] from "jetting" out of the joined surface between the hemispheres during [[implosion (mechanical process)|implosion]]. The core of the device used in the [[Trinity nuclear test]] at the [[Holloman Air Force Base|Alamogordo Bombing and Gunnery Range]] in July did not have such a ring.<ref>{{cite web| publisher=Restricted data blog| last=Wellerstein| first=Alex| title=You don't know ''Fat Man''| url=http://blog.nuclearsecrecy.com/2011/11/28/you-dont-know-fat-man/| access-date=April 4, 2014| url-status=live| archive-url=https://web.archive.org/web/20140407081651/http://blog.nuclearsecrecy.com/2011/11/28/you-dont-know-fat-man/| archive-date=April 7, 2014}}</ref><ref>{{cite book| last=Coster-Mullen| first=John| title=Core Differences, from "Atom Bombs: The Top Secret Inside Story of ''Little Boy'' and ''Fat Man''"| year=2010| url=https://www.flickr.com/photos/conqueror_worm/8165065513/in/photostream/| access-date=April 4, 2014| url-status=live| archive-url=https://web.archive.org/web/20140427063417/https://www.flickr.com/photos/conqueror_worm/8165065513/in/photostream/| archive-date=April 27, 2014}} An error: the illustration caption states the ''Fat Man'' core was plated in silver; it was plated in nickel, as the silver plating on the gadget core blistered. The disk in the drawings is a gold foil gasket.</ref>
[[File:Louis Slotin & Harry K. Daghlian Jr.jpg|thumb|The two physicists Harry Daghlian (center left) and Louis Slotin (center right) during the [[Trinity (nuclear test)|Trinity Test]]. Both died following supercriticality accidents involving the "demon core".]]
The [[Refining (metallurgy)|refined]] plutonium was shipped from the [[Hanford Site]] in [[Washington state]] to the [[Los Alamos Laboratory]]; an inventory document dated August 30 shows Los Alamos had expended "HS-1, 2, 3, 4; R-1" (the components of the Trinity and Nagasaki bombs) and had in its possession "HS-5, 6; R-2", finished and in the hands of quality control. Material for "HS-7, R-3" was in the Los Alamos metallurgy section, and would also be ready by September 5 (it is not certain whether this date allowed for the unmentioned "HS-8{{"'}}s fabrication to complete the fourth core).<ref name=third>{{cite web| title=The Third Core's Revenge| publisher=Restricted data blog| last=Wellerstein| first=Alex| url=http://blog.nuclearsecrecy.com/2013/08/16/the-third-cores-revenge/| access-date=April 4, 2014| url-status=live| archive-url=https://web.archive.org/web/20140407081649/http://blog.nuclearsecrecy.com/2013/08/16/the-third-cores-revenge/| archive-date=April 7, 2014}}</ref> The metallurgists used a [[plutonium-gallium alloy]], which stabilized the {{lang|el|δ}} phase [[allotropes of plutonium|allotrope of plutonium]] so it could be [[Hot pressing|hot pressed]] into the desired spherical shape. As plutonium was found to corrode readily, the sphere was then coated with [[nickel]].<ref>{{cite journal |last1=Baker |first1=Richard D. |last2=Hecker |first2=Siegfried S. |last3=Harbur |first3=Delbert R. |title=Plutonium: A Wartime Nightmare but a Metallurgist's Dream |url=http://library.lanl.gov/cgi-bin/getfile?07-16.pdf |journal=[[Los Alamos Science]] |issue=Winter/Spring |year=1983 |publisher=Los Alamos National Laboratory |pages=142–151 |access-date=22 November 2010 |url-status=live |archive-url=https://web.archive.org/web/20111017034523/http://library.lanl.gov/cgi-bin/getfile?07-16.pdf |archive-date=17 October 2011 }}</ref>
On August 10, [[Major General (United States)|Major General]] [[Leslie R. Groves, Jr.]], wrote to [[General of the Army (United States)|General of the Army]] [[George C. Marshall]], the [[Chief of Staff of the United States Army]], to inform him that:
{{quote|The next bomb of the implosion type had been scheduled to be ready for delivery on the target on the first good weather after August 24th, 1945. We have gained 4 days in manufacture and expect to ship the final components from New Mexico on August 12th or 13th. Providing there are no unforeseen difficulties in manufacture, in transportation to the theatre or after arrival in the theatre, the bomb should be ready for delivery on the first suitable weather after August 17th or 18th.<ref name=third/>}}
Marshall added an annotation, "It is not to be released on Japan without express authority from the President", as President [[Harry S. Truman]] was waiting to see the effects of the first two attacks.<ref name=third /> On August 13, the third bomb was scheduled. It was anticipated that it would be ready by August 16 to be dropped on August 19.<ref name=third /> This was pre-empted by [[Surrender of Japan|Japan's surrender on August 15, 1945]], while preparations were still being made for it to be couriered to [[Kirtland Air Force Base|Kirtland Field]]. The third core remained at Los Alamos.<ref>{{cite web|first1=Raemer|last1=Shreiber|author-link=Raemer Schreiber|first2=Richard|last2=Rhodes|author-link2=Richard Rhodes|title=Raemer Schreiber's Interview|year=1993|url=http://manhattanprojectvoices.org/oral-histories/raemer-schreibers-interview-1993|access-date=May 28, 2015|url-status=live|archive-url=https://web.archive.org/web/20150429100225/http://www.manhattanprojectvoices.org/oral-histories/raemer-schreibers-interview-1993|archive-date=April 29, 2015}} Raemer Schreiber being interviewed by Richard Rhodes</ref>
==First incident==
The core, assembled, was designed to be at "−5 [[Dollar (reactivity)|cents]]".<ref name="McLaughlin" /> In this state there is only a small safety margin against extraneous factors that might increase reactivity, causing the core to become supercritical, and then [[prompt critical]], a brief state of rapid energy increase.<ref>{{cite web |url=http://www.pipeline.com/~rstater/nuke1tttt.html |title=Prompt Criticality: A Concept with False Credentials |date=December 13, 2012 |access-date=September 27, 2015 |first=Robert G. |last=Stater |publisher=Nuke Facts |url-status=dead |archive-url=https://web.archive.org/web/20160304073037/http://www.pipeline.com/~rstater/nuke1tttt.html |archive-date=March 4, 2016 }}</ref> These factors are not common in the environment; they are circumstances like the compression of the solid metallic core (which would eventually be the method used to explode the bomb), the addition of more nuclear material, or provision of an external reflector which would reflect outbound [[neutron]]s back into the core. The experiments conducted at Los Alamos leading to the two fatal accidents were designed to guarantee that the core was indeed close to the critical point by arranging such reflectors and seeing how much neutron reflection was required to approach supercriticality.<ref name="McLaughlin" />
On August 21, 1945, the plutonium core produced a burst of [[neutron radiation]] that led to physicist [[Harry Daghlian]]'s death. Daghlian made a mistake while performing [[neutron reflector]] experiments on the core. He was working alone; a security guard, Private Robert J. Hemmerly, was seated at a desk {{convert|10|to|12|ft|m|0}} away.<ref name="hempelman"/> The core was placed within a stack of neutron-reflective [[tungsten carbide]] bricks and the addition of each brick moved the assembly closer to criticality. While attempting to stack another brick around the assembly, Daghlian accidentally dropped it onto the core and thereby caused the core to go well into supercriticality, a self-sustaining critical chain reaction. He quickly moved the brick off the assembly, but received a fatal dose of radiation. He died 25 days later from acute [[radiation poisoning]].<ref name="Millerp68">{{cite book |last=Miller |first=Richard L. |title=Under the Cloud: The Decades of Nuclear Testing |publisher=Two Sixty Press |location=The Woodlands, Texas |year=1991 |isbn=0-02-921620-6 |pages=[https://archive.org/details/underclouddec00mill/page/68 68, 77] |url=https://archive.org/details/underclouddec00mill/page/68 }}</ref>
{| class="wikitable"
|-
! scope=col| Name
! scope=col| Origin
! scope=col| Age at accident
! scope=col| Profession
! scope=col| Dose<ref name=hempelman>{{cite conference|last1=Hempelman|first1=Louis Henry|last2=Lushbaugh|first2=Clarence C.|last3=Voelz|first3=George L.|title=What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents?|conference=Conference for Radiation Accident Preparedness|date=October 19, 1979|url=http://www.orau.org/ptp/pdf/accidentsurvivorslanl.pdf|access-date=January 5, 2013|publisher=[[Los Alamos Scientific Laboratory]]|location=Oak Ridge|id=LA-UR-79-2802|url-status=live|archive-url=https://web.archive.org/web/20140912141857/http://www.orau.org/ptp/pdf/accidentsurvivorslanl.pdf|archive-date=September 12, 2014}} Patient numbers in this document have been identified as: 1 – Daghlian, 2 – Hemmerly, 3 – Slotin, 4 – Graves, 5 – Kline, 6 – Young, 7 – Cleary, 8 – Cieleski, 9 – Schreiber, 10 – Perlman</ref>
! scope=col| Aftermath
! scope=col| Reference
|-
| [[Harry Daghlian|Haroutune "Harry" Krikor Daghlian, Jr.]] || New London, Connecticut || style="text-align:center;" | 24 || Physicist || {{convert|200|rad|abbr=on|lk=on}} neutron<br />{{convert|110|rad|abbr=on}} [[gamma rays|gamma]] || Died 25 days after the accident of [[acute radiation syndrome]], [[haematopoiesis|haematopoietic]] focus
|| <ref name=ARS>{{cite web| last=Dion| first=Arnold| title=Acute Radiation Sickness| url=http://members.tripod.com/~Arnold_Dion/Daghlian/sickness.html |access-date=August 12, 2015 |publisher=Tripod }}</ref>
|-
| Private Robert J. Hemmerly || Whitehall, Ohio || style="text-align:center;"| 29 || [[Special Engineer Detachment]] (SED) guard || {{convert|8|rad|abbr=on}} neutron<br />{{convert|0.1|rad|abbr=on}} gamma || Died in 1978 (33 years after accident) of [[acute myelogenous leukemia]] at the age of 62
|| <ref name=ARS />
|}
==Second incident==
[[File:Tickling the Dragons Tail.jpg|thumb|A re-creation of the 1946 experiment. The half-sphere is seen, but the core inside is not. The beryllium hemisphere is held up with a screwdriver.]]
[[File:The demon core.jpg |thumb|]]
On May 21, 1946,<ref name=accidents>{{cite web |url=http://library.lanl.gov/cgi-bin/getfile?00314607.pdf |title=A Review of Criticality Accidents |date=September 26, 1967 |publisher=[[Los Alamos Scientific Laboratory]] |access-date=August 12, 2015 |url-status=live |archive-url=https://www.webcitation.org/6AZcUxVWG?url=http://library.lanl.gov/cgi-bin/getfile?00314607.pdf |archive-date=September 10, 2012 }}</ref> physicist [[Louis Slotin]] and seven other Los Alamos personnel were in a Los Alamos laboratory conducting another experiment to verify the closeness of the core to criticality by the positioning of neutron reflectors. Slotin, who was leaving Los Alamos, was showing the technique to [[Alvin C. Graves]], who would use it in a final test before the [[Operation Crossroads]] nuclear tests scheduled a month later at [[Bikini Atoll]]. It required the operator to place two half-spheres of [[beryllium]] (a neutron reflector) around the core to be tested and manually lower the top reflector over the core using a thumb hole on the top. As the reflectors were manually moved closer and farther away from each other, [[scintillation counters]] measured the relative activity from the core. The experimenter needed to maintain a slight separation between the reflector halves in order to stay below criticality. The standard protocol was to use [[shim (spacer)|shim]]s between the halves, as allowing them to close completely could result in the instantaneous formation of a critical mass and a lethal power excursion.
Under Slotin's own unapproved protocol, the shims were not used and the only thing preventing the closure was the blade of a standard flat-tipped [[screwdriver]] manipulated in Slotin's other hand. Slotin, who was given to bravado, became the local expert, performing the test on almost a dozen occasions, often in his trademark blue jeans and cowboy boots, in front of a roomful of observers. [[Enrico Fermi]] reportedly told Slotin and others they would be "dead within a year" if they continued performing the test in that manner.<ref>{{cite book | title = The Plutonium Files | last = Welsome | first = Eileen | page = [https://archive.org/details/plutoniumfiles00wels_0/page/184 184] | year = 1999 | isbn = 978-0-385-31402-2 | location = New York | publisher = Dial Press | url = https://archive.org/details/plutoniumfiles00wels_0/page/184 | access-date = November 18, 2012 }}</ref> Scientists referred to this flirting with the possibility of a nuclear chain reaction as "tickling the dragon's tail", based on a remark by physicist [[Richard Feynman]], who compared the experiments to "tickling the tail of a sleeping dragon".<ref name="NYT">{{cite news |last= Weber |first= Bruce |title=Theater Review; A Scientist's Tragic Hubris Attains Critical Mass Onstage |url=https://www.nytimes.com/2001/04/10/theater/theater-review-a-scientist-s-tragic-hubris-attains-critical-mass-onstage.html |work=New York Times |date=10 April 2001 |access-date=12 November 2007 }}</ref><ref>{{cite journal |date=November–December 2002 |title=Science as Theater: The Slip of the Screwdriver |journal=[[American Scientist]] |publisher=[[Sigma Xi]] |volume=90 |issue=6 |pages=550–555 |bibcode = 2002AmSci..90..550S |doi = 10.1511/2002.6.550 |last1= Shepherd-Barr |first1= Kirsten |last2= Lustig |first2= Harry }}</ref>
On the day of the accident, Slotin's screwdriver slipped outward a fraction of an inch while he was lowering the top reflector, allowing the reflector to fall into place around the core. Instantly, there was a flash of blue light and a wave of heat across Slotin's skin; the core had become supercritical, releasing an intense burst of [[neutron radiation]] estimated to have lasted about a half second.<ref name="McLaughlin">{{cite report | url=https://www.orau.org/PTP/Library/accidents/la-13638.pdf| access-date=May 18, 2014| title=A review of criticality incidents, 2000 Revision (LA-13638)| pages=70–78| first1=Thomas P.| last1=McLaughlin| first2=Shean P.| last2=Monahan| first3=Norman L.| last3=Pruvost| first4=Vladimir V.| last4=Frolov| first5=Boris G.| last5=Ryazanov| first6=Victor I.| last6=Sviridov| date=May 2000| url-status=live| archive-url=https://web.archive.org/web/20140722230204/http://www.orau.org/ptp/Library/accidents/la-13638.pdf| archive-date=July 22, 2014}}</ref> Slotin quickly twisted his wrist, flipping the top shell to the floor. The heating of the core and shells stopped the criticality within seconds of its initiation,<ref name=schreiber /><!--See Talk page, "Contradicting itself?"--> while Slotin's reaction prevented a recurrence and ended the accident. The position of Slotin's body over the apparatus also shielded the others from much of the neutron radiation, but he received a lethal dose of {{convert|1000|rad|abbr=on|lk=on}} neutron and {{convert|114|rad|abbr=on}} gamma radiation in under a second and died nine days later from acute radiation poisoning.
The nearest person to Slotin, Graves, who was watching over Slotin's shoulder and was thus partially shielded by him, received a high but non-lethal [[radiation dose]]. Graves was hospitalized for several weeks with severe radiation poisoning and developed chronic neurological and vision problems as a result of the exposure.<ref name="hempelman"/> He died 20 years later, at age 55, of a [[heart attack]]. It may have been caused by hidden complications from radiation exposure, but could also have been genetic in nature, as his father had died from the same cause.<ref>{{cite news|work=New York Times|url=https://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html|date=November 19, 1989|title=America's Radiation Victims: The Hidden Files|author=Clifford T. Honicker|page=11|url-status=live|archive-url=https://web.archive.org/web/20160831025102/http://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html|archive-date=August 31, 2016}}</ref><ref name="Alsop54">{{Cite news | last = Alsop | first = Stewart |author2=Robert E. Lapp | title = The Strange Death of Louis Slotin | newspaper = Saturday Evening Post | volume=226 | issue=36 | pages = 25ff | date = March 6, 1954 | url=http://dspace.wbpublibnet.gov.in:8080/jspui/bitstream/10689/11989/3/Chapter1_65-135p.pdf | access-date=April 3, 2014 |archive-url=https://web.archive.org/web/20141017051919/http://dspace.wbpublibnet.gov.in:8080/jspui/bitstream/10689/11989/3/Chapter1_65-135p.pdf |archive-date=October 17, 2014 }}</ref><ref>{{cite news | url=https://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html | title=America's Radiation Victims: The Hidden Files | author=Clifford T. Honicker | newspaper=The New York Times | date=November 19, 1989 | access-date=April 23, 2011 | url-status=live | archive-url=https://web.archive.org/web/20120217095609/http://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html | archive-date=February 17, 2012 }}</ref>
The second accident was reported by the [[Associated Press]] on 26 May 1946: "Four men injured through accidental exposure to radiation in the government's atomic laboratory here [Los Alamos] have been discharged from the hospital and 'immediate condition' of four others is satisfactory, the Army reported today. Dr. [[Norris E. Bradbury]], project director, said the men were injured last Tuesday in what he described as an experiment with fissionable material."<ref>Associated Press, "Several at Atomic Bomb Laboratory Injured", ''The San Bernardino Daily Sun'', San Bernardino, California, Monday 27 May 1946, Volume 52, page 1.</ref>
===Medical studies===
Follow-up research was conducted on the health of the men. An early report was published in 1951. A later report was compiled for the U.S. government and submitted in 1979.<ref name="hempelman"/> A summary of its findings:
{| class="wikitable"
|-
! Name !! Origin !! Age at accident!! Profession
! Dose<ref name="hempelman" /> !! Aftermath
!
|-
| [[Louis Slotin|Louis Alexander Slotin]] || Winnipeg, Manitoba, Canada || style="text-align:center;" | 35 || physicist || {{convert|1000|rad|abbr=on|lk=on}} neutron <br /> {{convert|114|rad|abbr=on}} gamma || died 9 days after the accident of [[acute radiation syndrome]], gastrointestinal focus
|| <ref name=accidents />
|-
| [[Alvin C. Graves]] || Austin, Texas || style="text-align:center;" | 34 || physicist || {{convert|166|rad|abbr=on}} neutron <br /> {{convert|26|rad|abbr=on}} gamma || died in 1965 (19 years after the accident) of [[myocardial infarction]], with aggravating "compensated [[myxedema]] and [[cataract]]s", while skiing
|| <ref name="hempelman" />
|-
| Samuel Allan Kline || Chicago, Illinois || style="text-align:center;" | 26 || physics student, later patent attorney
|| || died in 2001 (55 years after the accident); refused to take part in studies and was prevented from obtaining his own medical records from the incident || <ref name="hempelman" />
|-
| Marion Edward Cieslicki || Mt. Lebanon, Pennsylvania || style="text-align:center;" | 23 || physicist
|| {{convert|12|rad|abbr=on}} neutron <br /> {{convert|4|rad|abbr=on}} gamma || died of [[acute myelocytic leukemia]] in 1965 (19 years after the accident)
|| <ref name="hempelman" />
|-
| [[Dwight Smith Young]]||Chicago, Illinois || style="text-align:center;" | 54 || photographer
|| {{convert|51|rad|abbr=on}} neutron <br /> {{convert|11|rad|abbr=on}} gamma || died of [[aplastic anemia]] and [[infective endocarditis|bacterial endocarditis]] in 1975 (29 years after the accident)
|| <ref name="hempelman" />
|-
| [[Raemer E. Schreiber|Raemer Edgar Schreiber]] || McMinnville, Oregon || style="text-align:center;" | 36 || physicist
|| {{convert|9|rad|abbr=on}} neutron <br /> {{convert|3|rad|abbr=on}} gamma || died of natural causes in 1998 (52 years after the accident), at the age of 88
|| <ref name="hempelman" /><ref name="schreiber">{{cite news |title=Nuclear Naiveté |first=Larry |last=Calloway |newspaper=Albuquerque Journal |url=http://www.abqjournal.com/trinity/trinity2.pdf |access-date=August 12, 2015 |date=July 1995 |url-status=live |archive-url=https://web.archive.org/web/20150816161934/http://www.abqjournal.com/trinity/trinity2.pdf |archive-date=August 16, 2015 }}</ref>
|-
| Theodore Perlman || Louisiana || style="text-align:center;" | 23 || engineer
|| {{convert|7|rad|abbr=on}} neutron <br /> {{convert|2|rad|abbr=on}} gamma || "alive and in good health and spirits" as of 1978; probably died in June 1988 (42 years after the accident), in Livermore, California<ref>State of California. California Death Index, 1940–1997. Sacramento, CA, USA: State of California Department of Health Services, Center for Health Statistics.</ref>
|| <ref name="hempelman" />
|-
| Private Patrick Joseph Cleary || New York City || style="text-align:center;" | 21 || security guard
|| {{convert|33|rad|abbr=on}} neutron <br /> {{convert|9|rad|abbr=on}} gamma || Sergeant 1st Class Cleary was [[Killed in action|KIA]] on 3 Sep 1950 (4 years after the accident) while fighting in the 8th Cavalry Regiment, US Army in the [[Korean War]].<ref>American Battle Monuments Commission. Korean War Veterans Honor Roll. Ancestry.com. WWI, WWII, and Korean War Casualty Listings [database on-line]</ref><ref>{{cite web| title=Find a Grave: Patrick Joseph Cleary| url=https://www.findagrave.com/memorial/198440924| date=18 April 2019| author=K. White| website=Find a Grave}}</ref>
|| <ref name="hempelman" />
|}
Two machinists, Paul Long and another, unidentified, in another part of the building, {{convert|20-25|ft|m|round=0.5|abbr=on}} away, were not treated.<ref>{{cite journal | url=http://www.mphpa.org/classic/NPO/Slotin%20Accident.doc | title=Louis Slotin | access-date=April 4, 2014 | archive-url=https://web.archive.org/web/20140407070650/http://www.mphpa.org/classic/NPO/Slotin%20Accident.doc | archive-date=April 7, 2014}}</ref>
After these incidents the core, originally known as "Rufus", was referred to as the "demon core".<ref name=third /><ref name="New Yorker" /> Hands-on criticality experiments were stopped, and remote-control machines and TV cameras were designed by Schreiber, one of the survivors, to perform such experiments with all personnel at a quarter-mile distance.<ref name="schreiber"/>
==Planned uses and fate of the core==
The demon core was intended to be used in the [[Operation Crossroads]] nuclear tests, but after the criticality accident, time was needed for its radioactivity to decline and for it to be re-evaluated for the effects of the fission products it held, some of which could be very poisonous to the desired level of fission. The next two cores were shipped for use in ''Able'' and ''Baker'', and the demon core was scheduled to be shipped later for the third test of the series, provisionally named ''Charlie'', but that test was cancelled due to the unexpected level of radioactivity resulting from the underwater ''Baker'' test and the inability to decontaminate the target warships. The core was later melted down and the material recycled for use in other cores.<ref name="New Yorker">{{cite news| newspaper=[[The New Yorker]]| last=Wellerstein| first=Alex| title=The Demon Core and the Strange Death of Louis Slotin| url=http://www.newyorker.com/tech/elements/demon-core-the-strange-death-of-louis-slotin?intcid=mod-latest| date=May 21, 2016| access-date=May 22, 2016| url-status=live| archive-url=https://web.archive.org/web/20160524022150/http://www.newyorker.com/tech/elements/demon-core-the-strange-death-of-louis-slotin?intcid=mod-latest| archive-date=May 24, 2016}}</ref><ref>{{cite web |url=http://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/ |title=The blue flash |last=Wellerstein |first=Alex |publisher=Restricted Data |date=May 23, 2016 |access-date=23 May 2016 |url-status=live |archive-url=https://web.archive.org/web/20160524122659/http://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/ |archive-date=24 May 2016 }}</ref>
== See also ==
* [[Cecil Kelley criticality accident]]
==References==
{{Reflist}}
==External links==
* {{Commons category-inline|Demon core}}
{{Manhattan Project}}
{{Portal bar|History of Science|Nuclear technology|Physics|World War II}}
[[Category:Nuclear weapons]]
[[Category:Plutonium]]
[[Category:Nuclear accidents and incidents in the United States]]' |
New page wikitext, after the edit (new_wikitext) | '{{short description|Subcritical mass of plutonium used in the Manhattan Project}}
{{good article}}
[[File:Partially-reflected-plutonium-sphere.jpeg|300px|thumb|alt=A square base of metal blocks, with a smaller square of metal on the top in the centre, a metal ball (the "core") contained in its centre. A ruler along one side of the base shows it is roughly {{convert|10.5|in}} square.|A re-creation of the experiment involved in the 1945 incident. The sphere of plutonium is surrounded by [[neutron reflector|neutron-reflecting]] [[tungsten carbide]] blocks.]]
The '''demon core''' was a spherical {{convert|6.2|kg|lb|0|adj=on}} [[critical mass|subcritical mass]] of [[plutonium]] {{convert|89|mm|in}} in diameter, manufactured during [[World War II]] by the United States [[Timeline of nuclear weapons development|nuclear weapon development]] effort, the [[Manhattan Project]], as a fissile [[Pit (nuclear weapon)|core]] for an early [[atomic bomb]]. It was involved in two [[criticality accident]]s, on August 21, 1945, and May 21, 1946.
The core was intended for use in a possible third nuclear weapon to be [[Atomic bombings of Hiroshima and Nagasaki|dropped on Japan]], but when [[Japan's surrender]] made this unnecessary, it was repurposed for testing. It was designed with a small safety margin to ensure a successful [[Nuclear explosion|explosion]] of the bomb. The device briefly went [[supercritical mass|supercritical]] when it was accidentally placed in supercritical configurations during two separate experiments intended to guarantee the core was close to the critical point. The incidents happened at the [[Los Alamos Laboratory]], resulting in the acute [[radiation poisoning]] and subsequent deaths of scientists [[Harry Daghlian]] and [[Louis Slotin]], respectively. After these incidents the spherical plutonium core was referred to as the "demon core".
==Manufacturing and early history==
The demon [[Pit (nuclear weapon)|core]] (like the second core used in the [[Atomic bombings of Hiroshima and Nagasaki#Nagasaki|bombing of Nagasaki]]) was, when assembled, a solid {{convert|6.2|kg|lb|0|adj=on}} sphere measuring {{convert|89|mm|in}} in diameter. It consisted of three parts: two [[Plutonium–gallium alloy|plutonium-gallium]] hemispheres and a ring, designed to keep [[neutron flux]] from "jetting" out of the joined surface between the hemispheres during [[implosion (mechanical process)|implosion]]. The core of the device used in the [[Trinity nuclear test]] at the [[Holloman Air Force Base|Alamogordo Bombing and Gunnery Range]] in July did not have such a ring.<ref>{{cite web| publisher=Restricted data blog| last=Wellerstein| first=Alex| title=You don't know ''Fat Man''| url=http://blog.nuclearsecrecy.com/2011/11/28/you-dont-know-fat-man/| access-date=April 4, 2014| url-status=live| archive-url=https://web.archive.org/web/20140407081651/http://blog.nuclearsecrecy.com/2011/11/28/you-dont-know-fat-man/| archive-date=April 7, 2014}}</ref><ref>{{cite book| last=Coster-Mullen| first=John| title=Core Differences, from "Atom Bombs: The Top Secret Inside Story of ''Little Boy'' and ''Fat Man''"| year=2010| url=https://www.flickr.com/photos/conqueror_worm/8165065513/in/photostream/| access-date=April 4, 2014| url-status=live| archive-url=https://web.archive.org/web/20140427063417/https://www.flickr.com/photos/conqueror_worm/8165065513/in/photostream/| archive-date=April 27, 2014}} An error: the illustration caption states the ''Fat Man'' core was plated in silver; it was plated in nickel, as the silver plating on the gadget core blistered. The disk in the drawings is a gold foil gasket.</ref>
[[File:Louis Slotin & Harry K. Daghlian Jr.jpg|thumb|The two physicists Harry Daghlian (center left) and Louis Slotin (center right) during the [[Trinity (nuclear test)|Trinity Test]]. Both died following supercriticality accidents involving the "demon core".]]
The [[Refining (metallurgy)|refined]] plutonium was shipped from the [[Hanford Site]] in [[Washington state]] to the [[Los Alamos Laboratory]]; an inventory document dated August 30 shows Los Alamos had expended "HS-1, 2, 3, 4; R-1" (the components of the Trinity and Nagasaki bombs) and had in its possession "HS-5, 6; R-2", finished and in the hands of quality control. Material for "HS-7, R-3" was in the Los Alamos metallurgy section, and would also be ready by September 5 (it is not certain whether this date allowed for the unmentioned "HS-8{{"'}}s fabrication to complete the fourth core).<ref name=third>{{cite web| title=The Third Core's Revenge| publisher=Restricted data blog| last=Wellerstein| first=Alex| url=http://blog.nuclearsecrecy.com/2013/08/16/the-third-cores-revenge/| access-date=April 4, 2014| url-status=live| archive-url=https://web.archive.org/web/20140407081649/http://blog.nuclearsecrecy.com/2013/08/16/the-third-cores-revenge/| archive-date=April 7, 2014}}</ref> The metallurgists used a [[plutonium-gallium alloy]], which stabilized the {{lang|el|δ}} phase [[allotropes of plutonium|allotrope of plutonium]] so it could be [[Hot pressing|hot pressed]] into the desired spherical shape. As plutonium was found to corrode readily, the sphere was then coated with [[nickel]].<ref>{{cite journal |last1=Baker |first1=Richard D. |last2=Hecker |first2=Siegfried S. |last3=Harbur |first3=Delbert R. |title=Plutonium: A Wartime Nightmare but a Metallurgist's Dream |url=http://library.lanl.gov/cgi-bin/getfile?07-16.pdf |journal=[[Los Alamos Science]] |issue=Winter/Spring |year=1983 |publisher=Los Alamos National Laboratory |pages=142–151 |access-date=22 November 2010 |url-status=live |archive-url=https://web.archive.org/web/20111017034523/http://library.lanl.gov/cgi-bin/getfile?07-16.pdf |archive-date=17 October 2011 }}</ref>
On August 10, [[Major General (United States)|Major General]] [[Leslie R. Groves, Jr.]], wrote to [[General of the Army (United States)|General of the Army]] [[George C. Marshall]], the [[Chief of Staff of the United States Army]], to inform him that:
{{quote|The next bomb of the implosion type had been scheduled to be ready for delivery on the target on the first good weather after August 24th, 1945. We have gained 4 days in manufacture and expect to ship the final components from New Mexico on August 12th or 13th. Providing there are no unforeseen difficulties in manufacture, in transportation to the theatre or after arrival in the theatre, the bomb should be ready for delivery on the first suitable weather after August 17th or 18th.<ref name=third/>}}
Marshall added an annotation, "It is not to be released on Japan without express authority from the President", as President [[Harry S. Truman]] was waiting to see the effects of the first two attacks.<ref name=third /> On August 13, the third bomb was scheduled. It was anticipated that it would be ready by August 16 to be dropped on August 19.<ref name=third /> This was pre-empted by [[Surrender of Japan|Japan's surrender on August 15, 1945]], while preparations were still being made for it to be couriered to [[Kirtland Air Force Base|Kirtland Field]]. The third core remained at Los Alamos.<ref>{{cite web|first1=Raemer|last1=Shreiber|author-link=Raemer Schreiber|first2=Richard|last2=Rhodes|author-link2=Richard Rhodes|title=Raemer Schreiber's Interview|year=1993|url=http://manhattanprojectvoices.org/oral-histories/raemer-schreibers-interview-1993|access-date=May 28, 2015|url-status=live|archive-url=https://web.archive.org/web/20150429100225/http://www.manhattanprojectvoices.org/oral-histories/raemer-schreibers-interview-1993|archive-date=April 29, 2015}} Raemer Schreiber being interviewed by Richard Rhodes</ref>
==First incident==
The core, assembled, was designed to be at "−5 [[Dollar (reactivity)|cents]]".<ref name="McLaughlin" /> In this state there is only a small safety margin against extraneous factors that might increase reactivity, causing the core to become supercritical, and then [[prompt critical]], a brief state of rapid energy increase.<ref>{{cite web |url=http://www.pipeline.com/~rstater/nuke1tttt.html |title=Prompt Criticality: A Concept with False Credentials |date=December 13, 2012 |access-date=September 27, 2015 |first=Robert G. |last=Stater |publisher=Nuke Facts |url-status=dead |archive-url=https://web.archive.org/web/20160304073037/http://www.pipeline.com/~rstater/nuke1tttt.html |archive-date=March 4, 2016 }}</ref> These factors are not common in the environment; they are circumstances like the compression of the solid metallic core (which would eventually be the method used to explode the bomb), the addition of more nuclear material, or provision of an external reflector which would reflect outbound [[neutron]]s back into the core. The experiments conducted at Los Alamos leading to the two fatal accidents were designed to guarantee that the core was indeed close to the critical point by arranging such reflectors and seeing how much neutron reflection was required to approach supercriticality.<ref name="McLaughlin" />
On August 21, 1945, the plutonium core produced a burst of [[neutron radiation]] that led to physicist [[Harry Daghlian]]'s death. Daghlian made a mistake while performing [[neutron reflector]] experiments on the core. He was working alone; a security guard, Private Robert J. Hemmerly, was seated at a desk {{convert|10|to|12|ft|m|0}} away.<ref name="hempelman"/> The core was placed within a stack of neutron-reflective [[tungsten carbide]] bricks and the addition of each brick moved the assembly closer to criticality. While attempting to stack another brick around the assembly, Daghlian accidentally dropped it onto the core and thereby caused the core to go well into supercriticality, a self-sustaining critical chain reaction. He quickly moved the brick off the assembly, but received a fatal dose of radiation. He died 25 days later from acute [[radiation poisoning]].<ref name="Millerp68">{{cite book |last=Miller |first=Richard L. |title=Under the Cloud: The Decades of Nuclear Testing |publisher=Two Sixty Press |location=The Woodlands, Texas |year=1991 |isbn=0-02-921620-6 |pages=[https://archive.org/details/underclouddec00mill/page/68 68, 77] |url=https://archive.org/details/underclouddec00mill/page/68 }}</ref>
{| class="wikitable"
|-
! scope=col| Name
! scope=col| Origin
! scope=col| Age at accident
! scope=col| Profession
! scope=col| Dose<ref name=hempelman>{{cite conference|last1=Hempelman|first1=Louis Henry|last2=Lushbaugh|first2=Clarence C.|last3=Voelz|first3=George L.|title=What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents?|conference=Conference for Radiation Accident Preparedness|date=October 19, 1979|url=http://www.orau.org/ptp/pdf/accidentsurvivorslanl.pdf|access-date=January 5, 2013|publisher=[[Los Alamos Scientific Laboratory]]|location=Oak Ridge|id=LA-UR-79-2802|url-status=live|archive-url=https://web.archive.org/web/20140912141857/http://www.orau.org/ptp/pdf/accidentsurvivorslanl.pdf|archive-date=September 12, 2014}} Patient numbers in this document have been identified as: 1 – Daghlian, 2 – Hemmerly, 3 – Slotin, 4 – Graves, 5 – Kline, 6 – Young, 7 – Cleary, 8 – Cieleski, 9 – Schreiber, 10 – Perlman</ref>
! scope=col| Aftermath
! scope=col| Reference
|-
| [[Harry Daghlian|Haroutune "Harry" Krikor Daghlian, Jr.]] || New London, Connecticut || style="text-align:center;" | 24 || Physicist || {{convert|200|rad|abbr=on|lk=on}} neutron<br />{{convert|110|rad|abbr=on}} [[gamma rays|gamma]] || Died 25 days after the accident of [[acute radiation syndrome]], [[haematopoiesis|haematopoietic]] focus
|| <ref name=ARS>{{cite web| last=Dion| first=Arnold| title=Acute Radiation Sickness| url=http://members.tripod.com/~Arnold_Dion/Daghlian/sickness.html |access-date=August 12, 2015 |publisher=Tripod }}</ref>
|-
| Private Robert J. Hemmerly || Whitehall, Ohio || style="text-align:center;"| 29 || [[Special Engineer Detachment]] (SED) guard || {{convert|8|rad|abbr=on}} neutron<br />{{convert|0.1|rad|abbr=on}} gamma || Died in 1978 (33 years after accident) of [[acute myelogenous leukemia]] at the age of 62
|| <ref name=ARS />
|}
==Second incident==
[[File:Tickling the Dragons Tail.jpg|thumb|In 1948 scientists first discovered the phenomena now later described as a "Bruh Moment"]]
[[File:The demon core.jpg |thumb|]]
On May 21, 1946,<ref name=accidents>{{cite web |url=http://library.lanl.gov/cgi-bin/getfile?00314607.pdf |title=A Review of Criticality Accidents |date=September 26, 1967 |publisher=[[Los Alamos Scientific Laboratory]] |access-date=August 12, 2015 |url-status=live |archive-url=https://www.webcitation.org/6AZcUxVWG?url=http://library.lanl.gov/cgi-bin/getfile?00314607.pdf |archive-date=September 10, 2012 }}</ref> physicist [[Louis Slotin]] and seven other Los Alamos personnel were in a Los Alamos laboratory conducting another experiment to verify the closeness of the core to criticality by the positioning of neutron reflectors. Slotin, who was leaving Los Alamos, was showing the technique to [[Alvin C. Graves]], who would use it in a final test before the [[Operation Crossroads]] nuclear tests scheduled a month later at [[Bikini Atoll]]. It required the operator to place two half-spheres of [[beryllium]] (a neutron reflector) around the core to be tested and manually lower the top reflector over the core using a thumb hole on the top. As the reflectors were manually moved closer and farther away from each other, [[scintillation counters]] measured the relative activity from the core. The experimenter needed to maintain a slight separation between the reflector halves in order to stay below criticality. The standard protocol was to use [[shim (spacer)|shim]]s between the halves, as allowing them to close completely could result in the instantaneous formation of a critical mass and a lethal power excursion.
Under Slotin's own unapproved protocol, the shims were not used and the only thing preventing the closure was the blade of a standard flat-tipped [[screwdriver]] manipulated in Slotin's other hand. Slotin, who was given to bravado, became the local expert, performing the test on almost a dozen occasions, often in his trademark blue jeans and cowboy boots, in front of a roomful of observers. [[Enrico Fermi]] reportedly told Slotin and others they would be "dead within a year" if they continued performing the test in that manner.<ref>{{cite book | title = The Plutonium Files | last = Welsome | first = Eileen | page = [https://archive.org/details/plutoniumfiles00wels_0/page/184 184] | year = 1999 | isbn = 978-0-385-31402-2 | location = New York | publisher = Dial Press | url = https://archive.org/details/plutoniumfiles00wels_0/page/184 | access-date = November 18, 2012 }}</ref> Scientists referred to this flirting with the possibility of a nuclear chain reaction as "tickling the dragon's tail", based on a remark by physicist [[Richard Feynman]], who compared the experiments to "tickling the tail of a sleeping dragon".<ref name="NYT">{{cite news |last= Weber |first= Bruce |title=Theater Review; A Scientist's Tragic Hubris Attains Critical Mass Onstage |url=https://www.nytimes.com/2001/04/10/theater/theater-review-a-scientist-s-tragic-hubris-attains-critical-mass-onstage.html |work=New York Times |date=10 April 2001 |access-date=12 November 2007 }}</ref><ref>{{cite journal |date=November–December 2002 |title=Science as Theater: The Slip of the Screwdriver |journal=[[American Scientist]] |publisher=[[Sigma Xi]] |volume=90 |issue=6 |pages=550–555 |bibcode = 2002AmSci..90..550S |doi = 10.1511/2002.6.550 |last1= Shepherd-Barr |first1= Kirsten |last2= Lustig |first2= Harry }}</ref>
On the day of the accident, Slotin's screwdriver slipped outward a fraction of an inch while he was lowering the top reflector, allowing the reflector to fall into place around the core. Instantly, there was a flash of blue light and a wave of heat across Slotin's skin; the core had become supercritical, releasing an intense burst of [[neutron radiation]] estimated to have lasted about a half second.<ref name="McLaughlin">{{cite report | url=https://www.orau.org/PTP/Library/accidents/la-13638.pdf| access-date=May 18, 2014| title=A review of criticality incidents, 2000 Revision (LA-13638)| pages=70–78| first1=Thomas P.| last1=McLaughlin| first2=Shean P.| last2=Monahan| first3=Norman L.| last3=Pruvost| first4=Vladimir V.| last4=Frolov| first5=Boris G.| last5=Ryazanov| first6=Victor I.| last6=Sviridov| date=May 2000| url-status=live| archive-url=https://web.archive.org/web/20140722230204/http://www.orau.org/ptp/Library/accidents/la-13638.pdf| archive-date=July 22, 2014}}</ref> Slotin quickly twisted his wrist, flipping the top shell to the floor. The heating of the core and shells stopped the criticality within seconds of its initiation,<ref name=schreiber /><!--See Talk page, "Contradicting itself?"--> while Slotin's reaction prevented a recurrence and ended the accident. The position of Slotin's body over the apparatus also shielded the others from much of the neutron radiation, but he received a lethal dose of {{convert|1000|rad|abbr=on|lk=on}} neutron and {{convert|114|rad|abbr=on}} gamma radiation in under a second and died nine days later from acute radiation poisoning.
The nearest person to Slotin, Graves, who was watching over Slotin's shoulder and was thus partially shielded by him, received a high but non-lethal [[radiation dose]]. Graves was hospitalized for several weeks with severe radiation poisoning and developed chronic neurological and vision problems as a result of the exposure.<ref name="hempelman"/> He died 20 years later, at age 55, of a [[heart attack]]. It may have been caused by hidden complications from radiation exposure, but could also have been genetic in nature, as his father had died from the same cause.<ref>{{cite news|work=New York Times|url=https://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html|date=November 19, 1989|title=America's Radiation Victims: The Hidden Files|author=Clifford T. Honicker|page=11|url-status=live|archive-url=https://web.archive.org/web/20160831025102/http://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html|archive-date=August 31, 2016}}</ref><ref name="Alsop54">{{Cite news | last = Alsop | first = Stewart |author2=Robert E. Lapp | title = The Strange Death of Louis Slotin | newspaper = Saturday Evening Post | volume=226 | issue=36 | pages = 25ff | date = March 6, 1954 | url=http://dspace.wbpublibnet.gov.in:8080/jspui/bitstream/10689/11989/3/Chapter1_65-135p.pdf | access-date=April 3, 2014 |archive-url=https://web.archive.org/web/20141017051919/http://dspace.wbpublibnet.gov.in:8080/jspui/bitstream/10689/11989/3/Chapter1_65-135p.pdf |archive-date=October 17, 2014 }}</ref><ref>{{cite news | url=https://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html | title=America's Radiation Victims: The Hidden Files | author=Clifford T. Honicker | newspaper=The New York Times | date=November 19, 1989 | access-date=April 23, 2011 | url-status=live | archive-url=https://web.archive.org/web/20120217095609/http://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html | archive-date=February 17, 2012 }}</ref>
The second accident was reported by the [[Associated Press]] on 26 May 1946: "Four men injured through accidental exposure to radiation in the government's atomic laboratory here [Los Alamos] have been discharged from the hospital and 'immediate condition' of four others is satisfactory, the Army reported today. Dr. [[Norris E. Bradbury]], project director, said the men were injured last Tuesday in what he described as an experiment with fissionable material."<ref>Associated Press, "Several at Atomic Bomb Laboratory Injured", ''The San Bernardino Daily Sun'', San Bernardino, California, Monday 27 May 1946, Volume 52, page 1.</ref>
===Medical studies===
Follow-up research was conducted on the health of the men. An early report was published in 1951. A later report was compiled for the U.S. government and submitted in 1979.<ref name="hempelman"/> A summary of its findings:
{| class="wikitable"
|-
! Name !! Origin !! Age at accident!! Profession
! Dose<ref name="hempelman" /> !! Aftermath
!
|-
| [[Louis Slotin|Louis Alexander Slotin]] || Winnipeg, Manitoba, Canada || style="text-align:center;" | 35 || physicist || {{convert|1000|rad|abbr=on|lk=on}} neutron <br /> {{convert|114|rad|abbr=on}} gamma || died 9 days after the accident of [[acute radiation syndrome]], gastrointestinal focus
|| <ref name=accidents />
|-
| [[Alvin C. Graves]] || Austin, Texas || style="text-align:center;" | 34 || physicist || {{convert|166|rad|abbr=on}} neutron <br /> {{convert|26|rad|abbr=on}} gamma || died in 1965 (19 years after the accident) of [[myocardial infarction]], with aggravating "compensated [[myxedema]] and [[cataract]]s", while skiing
|| <ref name="hempelman" />
|-
| Samuel Allan Kline || Chicago, Illinois || style="text-align:center;" | 26 || physics student, later patent attorney
|| || died in 2001 (55 years after the accident); refused to take part in studies and was prevented from obtaining his own medical records from the incident || <ref name="hempelman" />
|-
| Marion Edward Cieslicki || Mt. Lebanon, Pennsylvania || style="text-align:center;" | 23 || physicist
|| {{convert|12|rad|abbr=on}} neutron <br /> {{convert|4|rad|abbr=on}} gamma || died of [[acute myelocytic leukemia]] in 1965 (19 years after the accident)
|| <ref name="hempelman" />
|-
| [[Dwight Smith Young]]||Chicago, Illinois || style="text-align:center;" | 54 || photographer
|| {{convert|51|rad|abbr=on}} neutron <br /> {{convert|11|rad|abbr=on}} gamma || died of [[aplastic anemia]] and [[infective endocarditis|bacterial endocarditis]] in 1975 (29 years after the accident)
|| <ref name="hempelman" />
|-
| [[Raemer E. Schreiber|Raemer Edgar Schreiber]] || McMinnville, Oregon || style="text-align:center;" | 36 || physicist
|| {{convert|9|rad|abbr=on}} neutron <br /> {{convert|3|rad|abbr=on}} gamma || died of natural causes in 1998 (52 years after the accident), at the age of 88
|| <ref name="hempelman" /><ref name="schreiber">{{cite news |title=Nuclear Naiveté |first=Larry |last=Calloway |newspaper=Albuquerque Journal |url=http://www.abqjournal.com/trinity/trinity2.pdf |access-date=August 12, 2015 |date=July 1995 |url-status=live |archive-url=https://web.archive.org/web/20150816161934/http://www.abqjournal.com/trinity/trinity2.pdf |archive-date=August 16, 2015 }}</ref>
|-
| Theodore Perlman || Louisiana || style="text-align:center;" | 23 || engineer
|| {{convert|7|rad|abbr=on}} neutron <br /> {{convert|2|rad|abbr=on}} gamma || "alive and in good health and spirits" as of 1978; probably died in June 1988 (42 years after the accident), in Livermore, California<ref>State of California. California Death Index, 1940–1997. Sacramento, CA, USA: State of California Department of Health Services, Center for Health Statistics.</ref>
|| <ref name="hempelman" />
|-
| Private Patrick Joseph Cleary || New York City || style="text-align:center;" | 21 || security guard
|| {{convert|33|rad|abbr=on}} neutron <br /> {{convert|9|rad|abbr=on}} gamma || Sergeant 1st Class Cleary was [[Killed in action|KIA]] on 3 Sep 1950 (4 years after the accident) while fighting in the 8th Cavalry Regiment, US Army in the [[Korean War]].<ref>American Battle Monuments Commission. Korean War Veterans Honor Roll. Ancestry.com. WWI, WWII, and Korean War Casualty Listings [database on-line]</ref><ref>{{cite web| title=Find a Grave: Patrick Joseph Cleary| url=https://www.findagrave.com/memorial/198440924| date=18 April 2019| author=K. White| website=Find a Grave}}</ref>
|| <ref name="hempelman" />
|}
Two machinists, Paul Long and another, unidentified, in another part of the building, {{convert|20-25|ft|m|round=0.5|abbr=on}} away, were not treated.<ref>{{cite journal | url=http://www.mphpa.org/classic/NPO/Slotin%20Accident.doc | title=Louis Slotin | access-date=April 4, 2014 | archive-url=https://web.archive.org/web/20140407070650/http://www.mphpa.org/classic/NPO/Slotin%20Accident.doc | archive-date=April 7, 2014}}</ref>
After these incidents the core, originally known as "Rufus", was referred to as the "demon core".<ref name=third /><ref name="New Yorker" /> Hands-on criticality experiments were stopped, and remote-control machines and TV cameras were designed by Schreiber, one of the survivors, to perform such experiments with all personnel at a quarter-mile distance.<ref name="schreiber"/>
==Planned uses and fate of the core==
The demon core was intended to be used in the [[Operation Crossroads]] nuclear tests, but after the criticality accident, time was needed for its radioactivity to decline and for it to be re-evaluated for the effects of the fission products it held, some of which could be very poisonous to the desired level of fission. The next two cores were shipped for use in ''Able'' and ''Baker'', and the demon core was scheduled to be shipped later for the third test of the series, provisionally named ''Charlie'', but that test was cancelled due to the unexpected level of radioactivity resulting from the underwater ''Baker'' test and the inability to decontaminate the target warships. The core was later melted down and the material recycled for use in other cores.<ref name="New Yorker">{{cite news| newspaper=[[The New Yorker]]| last=Wellerstein| first=Alex| title=The Demon Core and the Strange Death of Louis Slotin| url=http://www.newyorker.com/tech/elements/demon-core-the-strange-death-of-louis-slotin?intcid=mod-latest| date=May 21, 2016| access-date=May 22, 2016| url-status=live| archive-url=https://web.archive.org/web/20160524022150/http://www.newyorker.com/tech/elements/demon-core-the-strange-death-of-louis-slotin?intcid=mod-latest| archive-date=May 24, 2016}}</ref><ref>{{cite web |url=http://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/ |title=The blue flash |last=Wellerstein |first=Alex |publisher=Restricted Data |date=May 23, 2016 |access-date=23 May 2016 |url-status=live |archive-url=https://web.archive.org/web/20160524122659/http://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/ |archive-date=24 May 2016 }}</ref>
== See also ==
* [[Cecil Kelley criticality accident]]
==References==
{{Reflist}}
==External links==
* {{Commons category-inline|Demon core}}
{{Manhattan Project}}
{{Portal bar|History of Science|Nuclear technology|Physics|World War II}}
[[Category:Nuclear weapons]]
[[Category:Plutonium]]
[[Category:Nuclear accidents and incidents in the United States]]' |
Unified diff of changes made by edit (edit_diff) | '@@ -42,5 +42,5 @@
==Second incident==
-[[File:Tickling the Dragons Tail.jpg|thumb|A re-creation of the 1946 experiment. The half-sphere is seen, but the core inside is not. The beryllium hemisphere is held up with a screwdriver.]]
+[[File:Tickling the Dragons Tail.jpg|thumb|In 1948 scientists first discovered the phenomena now later described as a "Bruh Moment"]]
[[File:The demon core.jpg |thumb|]]
' |
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Parsed HTML source of the new revision (new_html) | '<div class="mw-parser-output"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Subcritical mass of plutonium used in the Manhattan Project</div>
<p class="mw-empty-elt">
</p>
<div class="thumb tright"><div class="thumbinner" style="width:302px;"><a href="/info/en/?search=File:Partially-reflected-plutonium-sphere.jpeg" class="image"><img alt="A square base of metal blocks, with a smaller square of metal on the top in the centre, a metal ball (the "core") contained in its centre. A ruler along one side of the base shows it is roughly 10.5 inches (270 mm) square." src="https://upload.wikimedia.org/wikipedia/commons/thumb/1/13/Partially-reflected-plutonium-sphere.jpeg/300px-Partially-reflected-plutonium-sphere.jpeg" decoding="async" width="300" height="240" class="thumbimage" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/1/13/Partially-reflected-plutonium-sphere.jpeg/450px-Partially-reflected-plutonium-sphere.jpeg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/13/Partially-reflected-plutonium-sphere.jpeg/600px-Partially-reflected-plutonium-sphere.jpeg 2x" data-file-width="800" data-file-height="640" /></a> <div class="thumbcaption"><div class="magnify"><a href="/info/en/?search=File:Partially-reflected-plutonium-sphere.jpeg" class="internal" title="Enlarge"></a></div>A re-creation of the experiment involved in the 1945 incident. The sphere of plutonium is surrounded by <a href="/info/en/?search=Neutron_reflector" title="Neutron reflector">neutron-reflecting</a> <a href="/info/en/?search=Tungsten_carbide" title="Tungsten carbide">tungsten carbide</a> blocks.</div></div></div>
<p>The <b>demon core</b> was a spherical 6.2-kilogram (14 lb) <a href="/info/en/?search=Critical_mass" title="Critical mass">subcritical mass</a> of <a href="/info/en/?search=Plutonium" title="Plutonium">plutonium</a> 89 millimetres (3.5 in) in diameter, manufactured during <a href="/info/en/?search=World_War_II" title="World War II">World War II</a> by the United States <a href="/info/en/?search=Timeline_of_nuclear_weapons_development" title="Timeline of nuclear weapons development">nuclear weapon development</a> effort, the <a href="/info/en/?search=Manhattan_Project" title="Manhattan Project">Manhattan Project</a>, as a fissile <a href="/info/en/?search=Pit_(nuclear_weapon)" title="Pit (nuclear weapon)">core</a> for an early <a href="/info/en/?search=Atomic_bomb" class="mw-redirect" title="Atomic bomb">atomic bomb</a>. It was involved in two <a href="/info/en/?search=Criticality_accident" title="Criticality accident">criticality accidents</a>, on August 21, 1945, and May 21, 1946.
</p><p>The core was intended for use in a possible third nuclear weapon to be <a href="/info/en/?search=Atomic_bombings_of_Hiroshima_and_Nagasaki" title="Atomic bombings of Hiroshima and Nagasaki">dropped on Japan</a>, but when <a href="/info/en/?search=Japan%27s_surrender" class="mw-redirect" title="Japan's surrender">Japan's surrender</a> made this unnecessary, it was repurposed for testing. It was designed with a small safety margin to ensure a successful <a href="/info/en/?search=Nuclear_explosion" title="Nuclear explosion">explosion</a> of the bomb. The device briefly went <a href="/info/en/?search=Supercritical_mass" class="mw-redirect" title="Supercritical mass">supercritical</a> when it was accidentally placed in supercritical configurations during two separate experiments intended to guarantee the core was close to the critical point. The incidents happened at the <a href="/info/en/?search=Los_Alamos_Laboratory" class="mw-redirect" title="Los Alamos Laboratory">Los Alamos Laboratory</a>, resulting in the acute <a href="/info/en/?search=Radiation_poisoning" class="mw-redirect" title="Radiation poisoning">radiation poisoning</a> and subsequent deaths of scientists <a href="/info/en/?search=Harry_Daghlian" title="Harry Daghlian">Harry Daghlian</a> and <a href="/info/en/?search=Louis_Slotin" title="Louis Slotin">Louis Slotin</a>, respectively. After these incidents the spherical plutonium core was referred to as the "demon core".
</p>
<div id="toc" class="toc" role="navigation" aria-labelledby="mw-toc-heading"><input type="checkbox" role="button" id="toctogglecheckbox" class="toctogglecheckbox" style="display:none" /><div class="toctitle" lang="en" dir="ltr"><h2 id="mw-toc-heading">Contents</h2><span class="toctogglespan"><label class="toctogglelabel" for="toctogglecheckbox"></label></span></div>
<ul>
<li class="toclevel-1 tocsection-1"><a href="#Manufacturing_and_early_history"><span class="tocnumber">1</span> <span class="toctext">Manufacturing and early history</span></a></li>
<li class="toclevel-1 tocsection-2"><a href="#First_incident"><span class="tocnumber">2</span> <span class="toctext">First incident</span></a></li>
<li class="toclevel-1 tocsection-3"><a href="#Second_incident"><span class="tocnumber">3</span> <span class="toctext">Second incident</span></a>
<ul>
<li class="toclevel-2 tocsection-4"><a href="#Medical_studies"><span class="tocnumber">3.1</span> <span class="toctext">Medical studies</span></a></li>
</ul>
</li>
<li class="toclevel-1 tocsection-5"><a href="#Planned_uses_and_fate_of_the_core"><span class="tocnumber">4</span> <span class="toctext">Planned uses and fate of the core</span></a></li>
<li class="toclevel-1 tocsection-6"><a href="#See_also"><span class="tocnumber">5</span> <span class="toctext">See also</span></a></li>
<li class="toclevel-1 tocsection-7"><a href="#References"><span class="tocnumber">6</span> <span class="toctext">References</span></a></li>
<li class="toclevel-1 tocsection-8"><a href="#External_links"><span class="tocnumber">7</span> <span class="toctext">External links</span></a></li>
</ul>
</div>
<h2><span class="mw-headline" id="Manufacturing_and_early_history">Manufacturing and early history</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=1" title="Edit section: Manufacturing and early history">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<p>The demon <a href="/info/en/?search=Pit_(nuclear_weapon)" title="Pit (nuclear weapon)">core</a> (like the second core used in the <a href="/info/en/?search=Atomic_bombings_of_Hiroshima_and_Nagasaki#Nagasaki" title="Atomic bombings of Hiroshima and Nagasaki">bombing of Nagasaki</a>) was, when assembled, a solid 6.2-kilogram (14 lb) sphere measuring 89 millimetres (3.5 in) in diameter. It consisted of three parts: two <a href="/info/en/?search=Plutonium%E2%80%93gallium_alloy" title="Plutonium–gallium alloy">plutonium-gallium</a> hemispheres and a ring, designed to keep <a href="/info/en/?search=Neutron_flux" title="Neutron flux">neutron flux</a> from "jetting" out of the joined surface between the hemispheres during <a href="/info/en/?search=Implosion_(mechanical_process)" title="Implosion (mechanical process)">implosion</a>. The core of the device used in the <a href="/info/en/?search=Trinity_nuclear_test" class="mw-redirect" title="Trinity nuclear test">Trinity nuclear test</a> at the <a href="/info/en/?search=Holloman_Air_Force_Base" title="Holloman Air Force Base">Alamogordo Bombing and Gunnery Range</a> in July did not have such a ring.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1">[1]</a></sup><sup id="cite_ref-2" class="reference"><a href="#cite_note-2">[2]</a></sup>
</p>
<div class="thumb tright"><div class="thumbinner" style="width:222px;"><a href="/info/en/?search=File:Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/a/a0/Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg/220px-Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg" decoding="async" width="220" height="165" class="thumbimage" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/a/a0/Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg/330px-Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a0/Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg/440px-Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg 2x" data-file-width="857" data-file-height="643" /></a> <div class="thumbcaption"><div class="magnify"><a href="/info/en/?search=File:Louis_Slotin_%26_Harry_K._Daghlian_Jr.jpg" class="internal" title="Enlarge"></a></div>The two physicists Harry Daghlian (center left) and Louis Slotin (center right) during the <a href="/info/en/?search=Trinity_(nuclear_test)" title="Trinity (nuclear test)">Trinity Test</a>. Both died following supercriticality accidents involving the "demon core".</div></div></div>
<p>The <a href="/info/en/?search=Refining_(metallurgy)" title="Refining (metallurgy)">refined</a> plutonium was shipped from the <a href="/info/en/?search=Hanford_Site" title="Hanford Site">Hanford Site</a> in <a href="/info/en/?search=Washington_state" class="mw-redirect" title="Washington state">Washington state</a> to the <a href="/info/en/?search=Los_Alamos_Laboratory" class="mw-redirect" title="Los Alamos Laboratory">Los Alamos Laboratory</a>; an inventory document dated August 30 shows Los Alamos had expended "HS-1, 2, 3, 4; R-1" (the components of the Trinity and Nagasaki bombs) and had in its possession "HS-5, 6; R-2", finished and in the hands of quality control. Material for "HS-7, R-3" was in the Los Alamos metallurgy section, and would also be ready by September 5 (it is not certain whether this date allowed for the unmentioned "HS-8<span style="padding-right:.15em;">"</span>'s fabrication to complete the fourth core).<sup id="cite_ref-third_3-0" class="reference"><a href="#cite_note-third-3">[3]</a></sup> The metallurgists used a <a href="/info/en/?search=Plutonium-gallium_alloy" class="mw-redirect" title="Plutonium-gallium alloy">plutonium-gallium alloy</a>, which stabilized the <span lang="el" title="Greek-language text">δ</span> phase <a href="/info/en/?search=Allotropes_of_plutonium" title="Allotropes of plutonium">allotrope of plutonium</a> so it could be <a href="/info/en/?search=Hot_pressing" title="Hot pressing">hot pressed</a> into the desired spherical shape. As plutonium was found to corrode readily, the sphere was then coated with <a href="/info/en/?search=Nickel" title="Nickel">nickel</a>.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4">[4]</a></sup>
</p><p>On August 10, <a href="/info/en/?search=Major_General_(United_States)" class="mw-redirect" title="Major General (United States)">Major General</a> <a href="/info/en/?search=Leslie_R._Groves,_Jr." class="mw-redirect" title="Leslie R. Groves, Jr.">Leslie R. Groves, Jr.</a>, wrote to <a href="/info/en/?search=General_of_the_Army_(United_States)" title="General of the Army (United States)">General of the Army</a> <a href="/info/en/?search=George_C._Marshall" title="George C. Marshall">George C. Marshall</a>, the <a href="/info/en/?search=Chief_of_Staff_of_the_United_States_Army" title="Chief of Staff of the United States Army">Chief of Staff of the United States Army</a>, to inform him that:
</p>
<style data-mw-deduplicate="TemplateStyles:r996844942">.mw-parser-output .templatequote{overflow:hidden;margin:1em 0;padding:0 40px}.mw-parser-output .templatequote .templatequotecite{line-height:1.5em;text-align:left;padding-left:1.6em;margin-top:0}</style><blockquote class="templatequote"><p>The next bomb of the implosion type had been scheduled to be ready for delivery on the target on the first good weather after August 24th, 1945. We have gained 4 days in manufacture and expect to ship the final components from New Mexico on August 12th or 13th. Providing there are no unforeseen difficulties in manufacture, in transportation to the theatre or after arrival in the theatre, the bomb should be ready for delivery on the first suitable weather after August 17th or 18th.<sup id="cite_ref-third_3-1" class="reference"><a href="#cite_note-third-3">[3]</a></sup></p></blockquote>
<p>Marshall added an annotation, "It is not to be released on Japan without express authority from the President", as President <a href="/info/en/?search=Harry_S._Truman" title="Harry S. Truman">Harry S. Truman</a> was waiting to see the effects of the first two attacks.<sup id="cite_ref-third_3-2" class="reference"><a href="#cite_note-third-3">[3]</a></sup> On August 13, the third bomb was scheduled. It was anticipated that it would be ready by August 16 to be dropped on August 19.<sup id="cite_ref-third_3-3" class="reference"><a href="#cite_note-third-3">[3]</a></sup> This was pre-empted by <a href="/info/en/?search=Surrender_of_Japan" title="Surrender of Japan">Japan's surrender on August 15, 1945</a>, while preparations were still being made for it to be couriered to <a href="/info/en/?search=Kirtland_Air_Force_Base" title="Kirtland Air Force Base">Kirtland Field</a>. The third core remained at Los Alamos.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5">[5]</a></sup>
</p>
<h2><span class="mw-headline" id="First_incident">First incident</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=2" title="Edit section: First incident">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<p>The core, assembled, was designed to be at "−5 <a href="/info/en/?search=Dollar_(reactivity)" title="Dollar (reactivity)">cents</a>".<sup id="cite_ref-McLaughlin_6-0" class="reference"><a href="#cite_note-McLaughlin-6">[6]</a></sup> In this state there is only a small safety margin against extraneous factors that might increase reactivity, causing the core to become supercritical, and then <a href="/info/en/?search=Prompt_critical" class="mw-redirect" title="Prompt critical">prompt critical</a>, a brief state of rapid energy increase.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7">[7]</a></sup> These factors are not common in the environment; they are circumstances like the compression of the solid metallic core (which would eventually be the method used to explode the bomb), the addition of more nuclear material, or provision of an external reflector which would reflect outbound <a href="/info/en/?search=Neutron" title="Neutron">neutrons</a> back into the core. The experiments conducted at Los Alamos leading to the two fatal accidents were designed to guarantee that the core was indeed close to the critical point by arranging such reflectors and seeing how much neutron reflection was required to approach supercriticality.<sup id="cite_ref-McLaughlin_6-1" class="reference"><a href="#cite_note-McLaughlin-6">[6]</a></sup>
</p><p>On August 21, 1945, the plutonium core produced a burst of <a href="/info/en/?search=Neutron_radiation" title="Neutron radiation">neutron radiation</a> that led to physicist <a href="/info/en/?search=Harry_Daghlian" title="Harry Daghlian">Harry Daghlian</a>'s death. Daghlian made a mistake while performing <a href="/info/en/?search=Neutron_reflector" title="Neutron reflector">neutron reflector</a> experiments on the core. He was working alone; a security guard, Private Robert J. Hemmerly, was seated at a desk 10 to 12 feet (3 to 4 m) away.<sup id="cite_ref-hempelman_8-0" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup> The core was placed within a stack of neutron-reflective <a href="/info/en/?search=Tungsten_carbide" title="Tungsten carbide">tungsten carbide</a> bricks and the addition of each brick moved the assembly closer to criticality. While attempting to stack another brick around the assembly, Daghlian accidentally dropped it onto the core and thereby caused the core to go well into supercriticality, a self-sustaining critical chain reaction. He quickly moved the brick off the assembly, but received a fatal dose of radiation. He died 25 days later from acute <a href="/info/en/?search=Radiation_poisoning" class="mw-redirect" title="Radiation poisoning">radiation poisoning</a>.<sup id="cite_ref-Millerp68_9-0" class="reference"><a href="#cite_note-Millerp68-9">[9]</a></sup>
</p>
<table class="wikitable">
<tbody><tr>
<th scope="col">Name
</th>
<th scope="col">Origin
</th>
<th scope="col">Age at accident
</th>
<th scope="col">Profession
</th>
<th scope="col">Dose<sup id="cite_ref-hempelman_8-1" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</th>
<th scope="col">Aftermath
</th>
<th scope="col">Reference
</th></tr>
<tr>
<td><a href="/info/en/?search=Harry_Daghlian" title="Harry Daghlian">Haroutune "Harry" Krikor Daghlian, Jr.</a></td>
<td>New London, Connecticut</td>
<td style="text-align:center;">24</td>
<td>Physicist</td>
<td>200 <a href="/info/en/?search=Rad_(unit)" title="Rad (unit)">rad</a> (2.0 <a href="/info/en/?search=Gray_(unit)" title="Gray (unit)">Gy</a>) neutron<br />110 rad (1.1 Gy) <a href="/info/en/?search=Gamma_rays" class="mw-redirect" title="Gamma rays">gamma</a></td>
<td>Died 25 days after the accident of <a href="/info/en/?search=Acute_radiation_syndrome" title="Acute radiation syndrome">acute radiation syndrome</a>, <a href="/info/en/?search=Haematopoiesis" title="Haematopoiesis">haematopoietic</a> focus
</td>
<td><sup id="cite_ref-ARS_10-0" class="reference"><a href="#cite_note-ARS-10">[10]</a></sup>
</td></tr>
<tr>
<td>Private Robert J. Hemmerly</td>
<td>Whitehall, Ohio</td>
<td style="text-align:center;">29</td>
<td><a href="/info/en/?search=Special_Engineer_Detachment" title="Special Engineer Detachment">Special Engineer Detachment</a> (SED) guard</td>
<td>8 rad (0.080 Gy) neutron<br />0.1 rad (0.0010 Gy) gamma</td>
<td>Died in 1978 (33 years after accident) of <a href="/info/en/?search=Acute_myelogenous_leukemia" class="mw-redirect" title="Acute myelogenous leukemia">acute myelogenous leukemia</a> at the age of 62
</td>
<td><sup id="cite_ref-ARS_10-1" class="reference"><a href="#cite_note-ARS-10">[10]</a></sup>
</td></tr></tbody></table>
<h2><span class="mw-headline" id="Second_incident">Second incident</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=3" title="Edit section: Second incident">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<div class="thumb tright"><div class="thumbinner" style="width:222px;"><a href="/info/en/?search=File:Tickling_the_Dragons_Tail.jpg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/d/db/Tickling_the_Dragons_Tail.jpg/220px-Tickling_the_Dragons_Tail.jpg" decoding="async" width="220" height="175" class="thumbimage" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/d/db/Tickling_the_Dragons_Tail.jpg/330px-Tickling_the_Dragons_Tail.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/db/Tickling_the_Dragons_Tail.jpg/440px-Tickling_the_Dragons_Tail.jpg 2x" data-file-width="1200" data-file-height="957" /></a> <div class="thumbcaption"><div class="magnify"><a href="/info/en/?search=File:Tickling_the_Dragons_Tail.jpg" class="internal" title="Enlarge"></a></div>In 1948 scientists first discovered the phenomena now later described as a "Bruh Moment"</div></div></div>
<div class="thumb tright"><div class="thumbinner" style="width:222px;"><a href="/info/en/?search=File:The_demon_core.jpg" class="image"><img alt="The demon core.jpg" src="https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/The_demon_core.jpg/220px-The_demon_core.jpg" decoding="async" width="220" height="175" class="thumbimage" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/The_demon_core.jpg/330px-The_demon_core.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6b/The_demon_core.jpg/440px-The_demon_core.jpg 2x" data-file-width="1200" data-file-height="957" /></a> <div class="thumbcaption"><div class="magnify"><a href="/info/en/?search=File:The_demon_core.jpg" class="internal" title="Enlarge"></a></div></div></div></div>
<p>On May 21, 1946,<sup id="cite_ref-accidents_11-0" class="reference"><a href="#cite_note-accidents-11">[11]</a></sup> physicist <a href="/info/en/?search=Louis_Slotin" title="Louis Slotin">Louis Slotin</a> and seven other Los Alamos personnel were in a Los Alamos laboratory conducting another experiment to verify the closeness of the core to criticality by the positioning of neutron reflectors. Slotin, who was leaving Los Alamos, was showing the technique to <a href="/info/en/?search=Alvin_C._Graves" title="Alvin C. Graves">Alvin C. Graves</a>, who would use it in a final test before the <a href="/info/en/?search=Operation_Crossroads" title="Operation Crossroads">Operation Crossroads</a> nuclear tests scheduled a month later at <a href="/info/en/?search=Bikini_Atoll" title="Bikini Atoll">Bikini Atoll</a>. It required the operator to place two half-spheres of <a href="/info/en/?search=Beryllium" title="Beryllium">beryllium</a> (a neutron reflector) around the core to be tested and manually lower the top reflector over the core using a thumb hole on the top. As the reflectors were manually moved closer and farther away from each other, <a href="/info/en/?search=Scintillation_counters" class="mw-redirect" title="Scintillation counters">scintillation counters</a> measured the relative activity from the core. The experimenter needed to maintain a slight separation between the reflector halves in order to stay below criticality. The standard protocol was to use <a href="/info/en/?search=Shim_(spacer)" title="Shim (spacer)">shims</a> between the halves, as allowing them to close completely could result in the instantaneous formation of a critical mass and a lethal power excursion.
</p><p>Under Slotin's own unapproved protocol, the shims were not used and the only thing preventing the closure was the blade of a standard flat-tipped <a href="/info/en/?search=Screwdriver" title="Screwdriver">screwdriver</a> manipulated in Slotin's other hand. Slotin, who was given to bravado, became the local expert, performing the test on almost a dozen occasions, often in his trademark blue jeans and cowboy boots, in front of a roomful of observers. <a href="/info/en/?search=Enrico_Fermi" title="Enrico Fermi">Enrico Fermi</a> reportedly told Slotin and others they would be "dead within a year" if they continued performing the test in that manner.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12">[12]</a></sup> Scientists referred to this flirting with the possibility of a nuclear chain reaction as "tickling the dragon's tail", based on a remark by physicist <a href="/info/en/?search=Richard_Feynman" title="Richard Feynman">Richard Feynman</a>, who compared the experiments to "tickling the tail of a sleeping dragon".<sup id="cite_ref-NYT_13-0" class="reference"><a href="#cite_note-NYT-13">[13]</a></sup><sup id="cite_ref-14" class="reference"><a href="#cite_note-14">[14]</a></sup>
</p><p>On the day of the accident, Slotin's screwdriver slipped outward a fraction of an inch while he was lowering the top reflector, allowing the reflector to fall into place around the core. Instantly, there was a flash of blue light and a wave of heat across Slotin's skin; the core had become supercritical, releasing an intense burst of <a href="/info/en/?search=Neutron_radiation" title="Neutron radiation">neutron radiation</a> estimated to have lasted about a half second.<sup id="cite_ref-McLaughlin_6-2" class="reference"><a href="#cite_note-McLaughlin-6">[6]</a></sup> Slotin quickly twisted his wrist, flipping the top shell to the floor. The heating of the core and shells stopped the criticality within seconds of its initiation,<sup id="cite_ref-schreiber_15-0" class="reference"><a href="#cite_note-schreiber-15">[15]</a></sup> while Slotin's reaction prevented a recurrence and ended the accident. The position of Slotin's body over the apparatus also shielded the others from much of the neutron radiation, but he received a lethal dose of 1,000 <a href="/info/en/?search=Rad_(unit)" title="Rad (unit)">rad</a> (10 <a href="/info/en/?search=Gray_(unit)" title="Gray (unit)">Gy</a>) neutron and 114 rad (1.14 Gy) gamma radiation in under a second and died nine days later from acute radiation poisoning.
</p><p>The nearest person to Slotin, Graves, who was watching over Slotin's shoulder and was thus partially shielded by him, received a high but non-lethal <a href="/info/en/?search=Radiation_dose" class="mw-redirect" title="Radiation dose">radiation dose</a>. Graves was hospitalized for several weeks with severe radiation poisoning and developed chronic neurological and vision problems as a result of the exposure.<sup id="cite_ref-hempelman_8-2" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup> He died 20 years later, at age 55, of a <a href="/info/en/?search=Heart_attack" class="mw-redirect" title="Heart attack">heart attack</a>. It may have been caused by hidden complications from radiation exposure, but could also have been genetic in nature, as his father had died from the same cause.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16">[16]</a></sup><sup id="cite_ref-Alsop54_17-0" class="reference"><a href="#cite_note-Alsop54-17">[17]</a></sup><sup id="cite_ref-18" class="reference"><a href="#cite_note-18">[18]</a></sup>
</p><p>The second accident was reported by the <a href="/info/en/?search=Associated_Press" title="Associated Press">Associated Press</a> on 26 May 1946: "Four men injured through accidental exposure to radiation in the government's atomic laboratory here [Los Alamos] have been discharged from the hospital and 'immediate condition' of four others is satisfactory, the Army reported today. Dr. <a href="/info/en/?search=Norris_E._Bradbury" class="mw-redirect" title="Norris E. Bradbury">Norris E. Bradbury</a>, project director, said the men were injured last Tuesday in what he described as an experiment with fissionable material."<sup id="cite_ref-19" class="reference"><a href="#cite_note-19">[19]</a></sup>
</p>
<h3><span class="mw-headline" id="Medical_studies">Medical studies</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=4" title="Edit section: Medical studies">edit source</a><span class="mw-editsection-bracket">]</span></span></h3>
<p>Follow-up research was conducted on the health of the men. An early report was published in 1951. A later report was compiled for the U.S. government and submitted in 1979.<sup id="cite_ref-hempelman_8-3" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup> A summary of its findings:
</p>
<table class="wikitable">
<tbody><tr>
<th>Name</th>
<th>Origin</th>
<th>Age at accident</th>
<th>Profession
</th>
<th>Dose<sup id="cite_ref-hempelman_8-4" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup></th>
<th>Aftermath
</th>
<th>
</th></tr>
<tr>
<td><a href="/info/en/?search=Louis_Slotin" title="Louis Slotin">Louis Alexander Slotin</a></td>
<td>Winnipeg, Manitoba, Canada</td>
<td style="text-align:center;">35</td>
<td>physicist</td>
<td>1,000 <a href="/info/en/?search=Rad_(unit)" title="Rad (unit)">rad</a> (10 <a href="/info/en/?search=Gray_(unit)" title="Gray (unit)">Gy</a>) neutron <br /> 114 rad (1.14 Gy) gamma</td>
<td>died 9 days after the accident of <a href="/info/en/?search=Acute_radiation_syndrome" title="Acute radiation syndrome">acute radiation syndrome</a>, gastrointestinal focus
</td>
<td><sup id="cite_ref-accidents_11-1" class="reference"><a href="#cite_note-accidents-11">[11]</a></sup>
</td></tr>
<tr>
<td><a href="/info/en/?search=Alvin_C._Graves" title="Alvin C. Graves">Alvin C. Graves</a></td>
<td>Austin, Texas</td>
<td style="text-align:center;">34</td>
<td>physicist</td>
<td>166 rad (1.66 Gy) neutron <br /> 26 rad (0.26 Gy) gamma</td>
<td>died in 1965 (19 years after the accident) of <a href="/info/en/?search=Myocardial_infarction" title="Myocardial infarction">myocardial infarction</a>, with aggravating "compensated <a href="/info/en/?search=Myxedema" title="Myxedema">myxedema</a> and <a href="/info/en/?search=Cataract" title="Cataract">cataracts</a>", while skiing
</td>
<td><sup id="cite_ref-hempelman_8-5" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</td></tr>
<tr>
<td>Samuel Allan Kline</td>
<td>Chicago, Illinois</td>
<td style="text-align:center;">26</td>
<td>physics student, later patent attorney
</td>
<td></td>
<td>died in 2001 (55 years after the accident); refused to take part in studies and was prevented from obtaining his own medical records from the incident</td>
<td><sup id="cite_ref-hempelman_8-6" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</td></tr>
<tr>
<td>Marion Edward Cieslicki</td>
<td>Mt. Lebanon, Pennsylvania</td>
<td style="text-align:center;">23</td>
<td>physicist
</td>
<td>12 rad (0.12 Gy) neutron <br /> 4 rad (0.040 Gy) gamma</td>
<td>died of <a href="/info/en/?search=Acute_myelocytic_leukemia" class="mw-redirect" title="Acute myelocytic leukemia">acute myelocytic leukemia</a> in 1965 (19 years after the accident)
</td>
<td><sup id="cite_ref-hempelman_8-7" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</td></tr>
<tr>
<td><a href="/info/en/?search=Dwight_Smith_Young" title="Dwight Smith Young">Dwight Smith Young</a></td>
<td>Chicago, Illinois</td>
<td style="text-align:center;">54</td>
<td>photographer
</td>
<td>51 rad (0.51 Gy) neutron <br /> 11 rad (0.11 Gy) gamma</td>
<td>died of <a href="/info/en/?search=Aplastic_anemia" title="Aplastic anemia">aplastic anemia</a> and <a href="/info/en/?search=Infective_endocarditis" title="Infective endocarditis">bacterial endocarditis</a> in 1975 (29 years after the accident)
</td>
<td><sup id="cite_ref-hempelman_8-8" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</td></tr>
<tr>
<td><a href="/info/en/?search=Raemer_E._Schreiber" class="mw-redirect" title="Raemer E. Schreiber">Raemer Edgar Schreiber</a></td>
<td>McMinnville, Oregon</td>
<td style="text-align:center;">36</td>
<td>physicist
</td>
<td>9 rad (0.090 Gy) neutron <br /> 3 rad (0.030 Gy) gamma</td>
<td>died of natural causes in 1998 (52 years after the accident), at the age of 88
</td>
<td><sup id="cite_ref-hempelman_8-9" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup><sup id="cite_ref-schreiber_15-1" class="reference"><a href="#cite_note-schreiber-15">[15]</a></sup>
</td></tr>
<tr>
<td>Theodore Perlman</td>
<td>Louisiana</td>
<td style="text-align:center;">23</td>
<td>engineer
</td>
<td>7 rad (0.070 Gy) neutron <br /> 2 rad (0.020 Gy) gamma</td>
<td>"alive and in good health and spirits" as of 1978; probably died in June 1988 (42 years after the accident), in Livermore, California<sup id="cite_ref-20" class="reference"><a href="#cite_note-20">[20]</a></sup>
</td>
<td><sup id="cite_ref-hempelman_8-10" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</td></tr>
<tr>
<td>Private Patrick Joseph Cleary</td>
<td>New York City</td>
<td style="text-align:center;">21</td>
<td>security guard
</td>
<td>33 rad (0.33 Gy) neutron <br /> 9 rad (0.090 Gy) gamma</td>
<td>Sergeant 1st Class Cleary was <a href="/info/en/?search=Killed_in_action" title="Killed in action">KIA</a> on 3 Sep 1950 (4 years after the accident) while fighting in the 8th Cavalry Regiment, US Army in the <a href="/info/en/?search=Korean_War" title="Korean War">Korean War</a>.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21">[21]</a></sup><sup id="cite_ref-22" class="reference"><a href="#cite_note-22">[22]</a></sup>
</td>
<td><sup id="cite_ref-hempelman_8-11" class="reference"><a href="#cite_note-hempelman-8">[8]</a></sup>
</td></tr></tbody></table>
<p>Two machinists, Paul Long and another, unidentified, in another part of the building, 20–25 ft (6–7.5 m) away, were not treated.<sup id="cite_ref-23" class="reference"><a href="#cite_note-23">[23]</a></sup>
</p><p>After these incidents the core, originally known as "Rufus", was referred to as the "demon core".<sup id="cite_ref-third_3-4" class="reference"><a href="#cite_note-third-3">[3]</a></sup><sup id="cite_ref-New_Yorker_24-0" class="reference"><a href="#cite_note-New_Yorker-24">[24]</a></sup> Hands-on criticality experiments were stopped, and remote-control machines and TV cameras were designed by Schreiber, one of the survivors, to perform such experiments with all personnel at a quarter-mile distance.<sup id="cite_ref-schreiber_15-2" class="reference"><a href="#cite_note-schreiber-15">[15]</a></sup>
</p>
<h2><span class="mw-headline" id="Planned_uses_and_fate_of_the_core">Planned uses and fate of the core</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=5" title="Edit section: Planned uses and fate of the core">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<p>The demon core was intended to be used in the <a href="/info/en/?search=Operation_Crossroads" title="Operation Crossroads">Operation Crossroads</a> nuclear tests, but after the criticality accident, time was needed for its radioactivity to decline and for it to be re-evaluated for the effects of the fission products it held, some of which could be very poisonous to the desired level of fission. The next two cores were shipped for use in <i>Able</i> and <i>Baker</i>, and the demon core was scheduled to be shipped later for the third test of the series, provisionally named <i>Charlie</i>, but that test was cancelled due to the unexpected level of radioactivity resulting from the underwater <i>Baker</i> test and the inability to decontaminate the target warships. The core was later melted down and the material recycled for use in other cores.<sup id="cite_ref-New_Yorker_24-1" class="reference"><a href="#cite_note-New_Yorker-24">[24]</a></sup><sup id="cite_ref-25" class="reference"><a href="#cite_note-25">[25]</a></sup>
</p>
<h2><span class="mw-headline" id="See_also">See also</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=6" title="Edit section: See also">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<ul><li><a href="/info/en/?search=Cecil_Kelley_criticality_accident" title="Cecil Kelley criticality accident">Cecil Kelley criticality accident</a></li></ul>
<h2><span class="mw-headline" id="References">References</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=7" title="Edit section: References">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<style data-mw-deduplicate="TemplateStyles:r1011085734">.mw-parser-output .reflist{font-size:90%;margin-bottom:0.5em;list-style-type:decimal}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist">
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<li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r999302996">.mw-parser-output cite.citation{font-style:inherit}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .id-lock-free a,.mw-parser-output .citation .cs1-lock-free a{background:linear-gradient(transparent,transparent),url("https://upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited a,.mw-parser-output .id-lock-registration a,.mw-parser-output .citation .cs1-lock-limited a,.mw-parser-output .citation .cs1-lock-registration a{background:linear-gradient(transparent,transparent),url("https://upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription a,.mw-parser-output .citation .cs1-lock-subscription a{background:linear-gradient(transparent,transparent),url("https://upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-ws-icon a{background:linear-gradient(transparent,transparent),url("https://upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{font-size:100%}.mw-parser-output .cs1-maint{display:none;color:#33aa33;margin-left:0.3em}.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}</style><cite id="CITEREFWellerstein" class="citation web cs1">Wellerstein, Alex. <a class="external text" href="https://blog.nuclearsecrecy.com/2011/11/28/you-dont-know-fat-man/">"You don't know <i>Fat Man</i>"</a>. Restricted data blog. <a class="external text" href="https://web.archive.org/web/20140407081651/http://blog.nuclearsecrecy.com/2011/11/28/you-dont-know-fat-man/">Archived</a> from the original on April 7, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">April 4,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=You+don%27t+know+Fat+Man&rft.pub=Restricted+data+blog&rft.aulast=Wellerstein&rft.aufirst=Alex&rft_id=http%3A%2F%2Fblog.nuclearsecrecy.com%2F2011%2F11%2F28%2Fyou-dont-know-fat-man%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFCoster-Mullen2010" class="citation book cs1">Coster-Mullen, John (2010). <a class="external text" href="https://www.flickr.com/photos/conqueror_worm/8165065513/in/photostream/"><i>Core Differences, from "Atom Bombs: The Top Secret Inside Story of </i>Little Boy<i> and </i>Fat Man<i>"</i></a>. <a class="external text" href="https://web.archive.org/web/20140427063417/https://www.flickr.com/photos/conqueror_worm/8165065513/in/photostream/">Archived</a> from the original on April 27, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">April 4,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Core+Differences%2C+from+%22Atom+Bombs%3A+The+Top+Secret+Inside+Story+of+Little+Boy+and+Fat+Man%22&rft.date=2010&rft.aulast=Coster-Mullen&rft.aufirst=John&rft_id=https%3A%2F%2Fwww.flickr.com%2Fphotos%2Fconqueror_worm%2F8165065513%2Fin%2Fphotostream%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span> An error: the illustration caption states the <i>Fat Man</i> core was plated in silver; it was plated in nickel, as the silver plating on the gadget core blistered. The disk in the drawings is a gold foil gasket.</span>
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<li id="cite_note-third-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-third_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-third_3-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-third_3-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-third_3-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-third_3-4"><sup><i><b>e</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFWellerstein" class="citation web cs1">Wellerstein, Alex. <a class="external text" href="https://blog.nuclearsecrecy.com/2013/08/16/the-third-cores-revenge/">"The Third Core's Revenge"</a>. Restricted data blog. <a class="external text" href="https://web.archive.org/web/20140407081649/http://blog.nuclearsecrecy.com/2013/08/16/the-third-cores-revenge/">Archived</a> from the original on April 7, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">April 4,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+Third+Core%27s+Revenge&rft.pub=Restricted+data+blog&rft.aulast=Wellerstein&rft.aufirst=Alex&rft_id=http%3A%2F%2Fblog.nuclearsecrecy.com%2F2013%2F08%2F16%2Fthe-third-cores-revenge%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFBakerHeckerHarbur1983" class="citation journal cs1">Baker, Richard D.; Hecker, Siegfried S.; Harbur, Delbert R. (1983). <a class="external text" href="https://library.lanl.gov/cgi-bin/getfile?07-16.pdf">"Plutonium: A Wartime Nightmare but a Metallurgist's Dream"</a> <span class="cs1-format">(PDF)</span>. <i><a href="/info/en/?search=Los_Alamos_Science" title="Los Alamos Science">Los Alamos Science</a></i>. Los Alamos National Laboratory (Winter/Spring): 142–151. <a class="external text" href="https://web.archive.org/web/20111017034523/http://library.lanl.gov/cgi-bin/getfile?07-16.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 17 October 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">22 November</span> 2010</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Los+Alamos+Science&rft.atitle=Plutonium%3A+A+Wartime+Nightmare+but+a+Metallurgist%27s+Dream&rft.issue=Winter%2FSpring&rft.pages=142-151&rft.date=1983&rft.aulast=Baker&rft.aufirst=Richard+D.&rft.au=Hecker%2C+Siegfried+S.&rft.au=Harbur%2C+Delbert+R.&rft_id=http%3A%2F%2Flibrary.lanl.gov%2Fcgi-bin%2Fgetfile%3F07-16.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFShreiberRhodes1993" class="citation web cs1"><a href="/info/en/?search=Raemer_Schreiber" title="Raemer Schreiber">Shreiber, Raemer</a>; <a href="/info/en/?search=Richard_Rhodes" title="Richard Rhodes">Rhodes, Richard</a> (1993). <a class="external text" href="https://manhattanprojectvoices.org/oral-histories/raemer-schreibers-interview-1993">"Raemer Schreiber's Interview"</a>. <a class="external text" href="https://web.archive.org/web/20150429100225/http://www.manhattanprojectvoices.org/oral-histories/raemer-schreibers-interview-1993">Archived</a> from the original on April 29, 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">May 28,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Raemer+Schreiber%27s+Interview&rft.date=1993&rft.aulast=Shreiber&rft.aufirst=Raemer&rft.au=Rhodes%2C+Richard&rft_id=http%3A%2F%2Fmanhattanprojectvoices.org%2Foral-histories%2Fraemer-schreibers-interview-1993&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span> Raemer Schreiber being interviewed by Richard Rhodes</span>
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<li id="cite_note-McLaughlin-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-McLaughlin_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-McLaughlin_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-McLaughlin_6-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFMcLaughlinMonahanPruvostFrolov2000" class="citation report cs1">McLaughlin, Thomas P.; Monahan, Shean P.; Pruvost, Norman L.; Frolov, Vladimir V.; Ryazanov, Boris G.; Sviridov, Victor I. (May 2000). <a class="external text" href="https://www.orau.org/PTP/Library/accidents/la-13638.pdf">A review of criticality incidents, 2000 Revision (LA-13638)</a> <span class="cs1-format">(PDF)</span> (Report). pp. 70–78. <a class="external text" href="https://web.archive.org/web/20140722230204/http://www.orau.org/ptp/Library/accidents/la-13638.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on July 22, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">May 18,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=report&rft.btitle=A+review+of+criticality+incidents%2C+2000+Revision+%28LA-13638%29&rft.pages=70-78&rft.date=2000-05&rft.aulast=McLaughlin&rft.aufirst=Thomas+P.&rft.au=Monahan%2C+Shean+P.&rft.au=Pruvost%2C+Norman+L.&rft.au=Frolov%2C+Vladimir+V.&rft.au=Ryazanov%2C+Boris+G.&rft.au=Sviridov%2C+Victor+I.&rft_id=https%3A%2F%2Fwww.orau.org%2FPTP%2FLibrary%2Faccidents%2Fla-13638.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFStater2012" class="citation web cs1">Stater, Robert G. (December 13, 2012). <a class="external text" href="https://web.archive.org/web/20160304073037/http://www.pipeline.com/~rstater/nuke1tttt.html">"Prompt Criticality: A Concept with False Credentials"</a>. Nuke Facts. Archived from <a class="external text" href="https://www.pipeline.com/~rstater/nuke1tttt.html">the original</a> on March 4, 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">September 27,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Prompt+Criticality%3A+A+Concept+with+False+Credentials&rft.pub=Nuke+Facts&rft.date=2012-12-13&rft.aulast=Stater&rft.aufirst=Robert+G.&rft_id=http%3A%2F%2Fwww.pipeline.com%2F~rstater%2Fnuke1tttt.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-hempelman-8"><span class="mw-cite-backlink">^ <a href="#cite_ref-hempelman_8-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-hempelman_8-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-hempelman_8-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-hempelman_8-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-hempelman_8-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-hempelman_8-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-hempelman_8-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-hempelman_8-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-hempelman_8-8"><sup><i><b>i</b></i></sup></a> <a href="#cite_ref-hempelman_8-9"><sup><i><b>j</b></i></sup></a> <a href="#cite_ref-hempelman_8-10"><sup><i><b>k</b></i></sup></a> <a href="#cite_ref-hempelman_8-11"><sup><i><b>l</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFHempelmanLushbaughVoelz1979" class="citation conference cs1">Hempelman, Louis Henry; Lushbaugh, Clarence C.; Voelz, George L. (October 19, 1979). <a class="external text" href="https://www.orau.org/ptp/pdf/accidentsurvivorslanl.pdf"><i>What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents?</i></a> <span class="cs1-format">(PDF)</span>. Conference for Radiation Accident Preparedness. Oak Ridge: <a href="/info/en/?search=Los_Alamos_Scientific_Laboratory" class="mw-redirect" title="Los Alamos Scientific Laboratory">Los Alamos Scientific Laboratory</a>. LA-UR-79-2802. <a class="external text" href="https://web.archive.org/web/20140912141857/http://www.orau.org/ptp/pdf/accidentsurvivorslanl.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on September 12, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">January 5,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.btitle=What+Has+Happened+to+the+Survivors+of+the+Early+Los+Alamos+Nuclear+Accidents%3F&rft.place=Oak+Ridge&rft.pub=Los+Alamos+Scientific+Laboratory&rft.date=1979-10-19&rft.aulast=Hempelman&rft.aufirst=Louis+Henry&rft.au=Lushbaugh%2C+Clarence+C.&rft.au=Voelz%2C+George+L.&rft_id=http%3A%2F%2Fwww.orau.org%2Fptp%2Fpdf%2Faccidentsurvivorslanl.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span> Patient numbers in this document have been identified as: 1 – Daghlian, 2 – Hemmerly, 3 – Slotin, 4 – Graves, 5 – Kline, 6 – Young, 7 – Cleary, 8 – Cieleski, 9 – Schreiber, 10 – Perlman</span>
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<li id="cite_note-Millerp68-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-Millerp68_9-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFMiller1991" class="citation book cs1">Miller, Richard L. (1991). <a class="external text" href="https://archive.org/details/underclouddec00mill/page/68"><i>Under the Cloud: The Decades of Nuclear Testing</i></a>. The Woodlands, Texas: Two Sixty Press. pp. <a class="external text" href="https://archive.org/details/underclouddec00mill/page/68">68, 77</a>. <a href="/info/en/?search=ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/info/en/?search=Special:BookSources/0-02-921620-6" title="Special:BookSources/0-02-921620-6"><bdi>0-02-921620-6</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Under+the+Cloud%3A+The+Decades+of+Nuclear+Testing&rft.place=The+Woodlands%2C+Texas&rft.pages=68%2C+77&rft.pub=Two+Sixty+Press&rft.date=1991&rft.isbn=0-02-921620-6&rft.aulast=Miller&rft.aufirst=Richard+L.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Funderclouddec00mill%2Fpage%2F68&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-ARS-10"><span class="mw-cite-backlink">^ <a href="#cite_ref-ARS_10-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-ARS_10-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFDion" class="citation web cs1">Dion, Arnold. <a class="external text" href="https://members.tripod.com/~Arnold_Dion/Daghlian/sickness.html">"Acute Radiation Sickness"</a>. Tripod<span class="reference-accessdate">. Retrieved <span class="nowrap">August 12,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Acute+Radiation+Sickness&rft.pub=Tripod&rft.aulast=Dion&rft.aufirst=Arnold&rft_id=http%3A%2F%2Fmembers.tripod.com%2F~Arnold_Dion%2FDaghlian%2Fsickness.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-accidents-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-accidents_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-accidents_11-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite class="citation web cs1"><a class="external text" href="https://library.lanl.gov/cgi-bin/getfile?00314607.pdf">"A Review of Criticality Accidents"</a> <span class="cs1-format">(PDF)</span>. <a href="/info/en/?search=Los_Alamos_Scientific_Laboratory" class="mw-redirect" title="Los Alamos Scientific Laboratory">Los Alamos Scientific Laboratory</a>. September 26, 1967. <a class="external text" href="https://www.webcitation.org/6AZcUxVWG?url=http://library.lanl.gov/cgi-bin/getfile?00314607.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on September 10, 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">August 12,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=A+Review+of+Criticality+Accidents&rft.pub=Los+Alamos+Scientific+Laboratory&rft.date=1967-09-26&rft_id=http%3A%2F%2Flibrary.lanl.gov%2Fcgi-bin%2Fgetfile%3F00314607.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFWelsome1999" class="citation book cs1">Welsome, Eileen (1999). <a class="external text" href="https://archive.org/details/plutoniumfiles00wels_0/page/184"><i>The Plutonium Files</i></a>. New York: Dial Press. p. <a class="external text" href="https://archive.org/details/plutoniumfiles00wels_0/page/184">184</a>. <a href="/info/en/?search=ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/info/en/?search=Special:BookSources/978-0-385-31402-2" title="Special:BookSources/978-0-385-31402-2"><bdi>978-0-385-31402-2</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">November 18,</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Plutonium+Files&rft.place=New+York&rft.pages=184&rft.pub=Dial+Press&rft.date=1999&rft.isbn=978-0-385-31402-2&rft.aulast=Welsome&rft.aufirst=Eileen&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fplutoniumfiles00wels_0%2Fpage%2F184&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-NYT-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-NYT_13-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFWeber2001" class="citation news cs1">Weber, Bruce (10 April 2001). <a class="external text" href="https://www.nytimes.com/2001/04/10/theater/theater-review-a-scientist-s-tragic-hubris-attains-critical-mass-onstage.html">"Theater Review; A Scientist's Tragic Hubris Attains Critical Mass Onstage"</a>. <i>New York Times</i><span class="reference-accessdate">. Retrieved <span class="nowrap">12 November</span> 2007</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=New+York+Times&rft.atitle=Theater+Review%3B+A+Scientist%27s+Tragic+Hubris+Attains+Critical+Mass+Onstage&rft.date=2001-04-10&rft.aulast=Weber&rft.aufirst=Bruce&rft_id=https%3A%2F%2Fwww.nytimes.com%2F2001%2F04%2F10%2Ftheater%2Ftheater-review-a-scientist-s-tragic-hubris-attains-critical-mass-onstage.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
<li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFShepherd-BarrLustig2002" class="citation journal cs1">Shepherd-Barr, Kirsten; Lustig, Harry (November–December 2002). "Science as Theater: The Slip of the Screwdriver". <i><a href="/info/en/?search=American_Scientist" title="American Scientist">American Scientist</a></i>. <a href="/info/en/?search=Sigma_Xi" title="Sigma Xi">Sigma Xi</a>. <b>90</b> (6): 550–555. <a href="/info/en/?search=Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a class="external text" href="https://ui.adsabs.harvard.edu/abs/2002AmSci..90..550S">2002AmSci..90..550S</a>. <a href="/info/en/?search=Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a class="external text" href="https://doi.org/10.1511%2F2002.6.550">10.1511/2002.6.550</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=American+Scientist&rft.atitle=Science+as+Theater%3A+The+Slip+of+the+Screwdriver&rft.volume=90&rft.issue=6&rft.pages=550-555&rft.date=2002-11%2F2002-12&rft_id=info%3Adoi%2F10.1511%2F2002.6.550&rft_id=info%3Abibcode%2F2002AmSci..90..550S&rft.aulast=Shepherd-Barr&rft.aufirst=Kirsten&rft.au=Lustig%2C+Harry&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-schreiber-15"><span class="mw-cite-backlink">^ <a href="#cite_ref-schreiber_15-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-schreiber_15-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-schreiber_15-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFCalloway1995" class="citation news cs1">Calloway, Larry (July 1995). <a class="external text" href="https://www.abqjournal.com/trinity/trinity2.pdf">"Nuclear Naiveté"</a> <span class="cs1-format">(PDF)</span>. <i>Albuquerque Journal</i>. <a class="external text" href="https://web.archive.org/web/20150816161934/http://www.abqjournal.com/trinity/trinity2.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on August 16, 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">August 12,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Albuquerque+Journal&rft.atitle=Nuclear+Naivet%C3%A9&rft.date=1995-07&rft.aulast=Calloway&rft.aufirst=Larry&rft_id=http%3A%2F%2Fwww.abqjournal.com%2Ftrinity%2Ftrinity2.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
<li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFClifford_T._Honicker1989" class="citation news cs1">Clifford T. Honicker (November 19, 1989). <a class="external text" href="https://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html">"America's Radiation Victims: The Hidden Files"</a>. <i>New York Times</i>. p. 11. <a class="external text" href="https://web.archive.org/web/20160831025102/http://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html">Archived</a> from the original on August 31, 2016.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=New+York+Times&rft.atitle=America%27s+Radiation+Victims%3A+The+Hidden+Files&rft.pages=11&rft.date=1989-11-19&rft.au=Clifford+T.+Honicker&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1989%2F11%2F19%2Fmagazine%2Famerica-s-radiation-victims-the-hidden-files.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
<li id="cite_note-Alsop54-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-Alsop54_17-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFAlsopRobert_E._Lapp1954" class="citation news cs1">Alsop, Stewart; Robert E. Lapp (March 6, 1954). <a class="external text" href="https://web.archive.org/web/20141017051919/http://dspace.wbpublibnet.gov.in:8080/jspui/bitstream/10689/11989/3/Chapter1_65-135p.pdf">"The Strange Death of Louis Slotin"</a> <span class="cs1-format">(PDF)</span>. <i>Saturday Evening Post</i>. <b>226</b> (36). pp. 25ff. Archived from <a class="external text" href="https://dspace.wbpublibnet.gov.in:8080/jspui/bitstream/10689/11989/3/Chapter1_65-135p.pdf">the original</a> <span class="cs1-format">(PDF)</span> on October 17, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">April 3,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Saturday+Evening+Post&rft.atitle=The+Strange+Death+of+Louis+Slotin&rft.volume=226&rft.issue=36&rft.pages=25ff&rft.date=1954-03-06&rft.aulast=Alsop&rft.aufirst=Stewart&rft.au=Robert+E.+Lapp&rft_id=http%3A%2F%2Fdspace.wbpublibnet.gov.in%3A8080%2Fjspui%2Fbitstream%2F10689%2F11989%2F3%2FChapter1_65-135p.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
<li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFClifford_T._Honicker1989" class="citation news cs1">Clifford T. Honicker (November 19, 1989). <a class="external text" href="https://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html">"America's Radiation Victims: The Hidden Files"</a>. <i>The New York Times</i>. <a class="external text" href="https://web.archive.org/web/20120217095609/http://www.nytimes.com/1989/11/19/magazine/america-s-radiation-victims-the-hidden-files.html">Archived</a> from the original on February 17, 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">April 23,</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+York+Times&rft.atitle=America%27s+Radiation+Victims%3A+The+Hidden+Files&rft.date=1989-11-19&rft.au=Clifford+T.+Honicker&rft_id=https%3A%2F%2Fwww.nytimes.com%2F1989%2F11%2F19%2Fmagazine%2Famerica-s-radiation-victims-the-hidden-files.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
<li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text">Associated Press, "Several at Atomic Bomb Laboratory Injured", <i>The San Bernardino Daily Sun</i>, San Bernardino, California, Monday 27 May 1946, Volume 52, page 1.</span>
</li>
<li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text">State of California. California Death Index, 1940–1997. Sacramento, CA, USA: State of California Department of Health Services, Center for Health Statistics.</span>
</li>
<li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text">American Battle Monuments Commission. Korean War Veterans Honor Roll. Ancestry.com. WWI, WWII, and Korean War Casualty Listings [database on-line]</span>
</li>
<li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFK._White2019" class="citation web cs1">K. White (18 April 2019). <a class="external text" href="https://www.findagrave.com/memorial/198440924">"Find a Grave: Patrick Joseph Cleary"</a>. <i>Find a Grave</i>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Find+a+Grave&rft.atitle=Find+a+Grave%3A+Patrick+Joseph+Cleary&rft.date=2019-04-18&rft.au=K.+White&rft_id=https%3A%2F%2Fwww.findagrave.com%2Fmemorial%2F198440924&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
<li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite class="citation journal cs1"><a class="external text" href="https://web.archive.org/web/20140407070650/http://www.mphpa.org/classic/NPO/Slotin%20Accident.doc">"Louis Slotin"</a>. Archived from <a class="external text" href="https://www.mphpa.org/classic/NPO/Slotin%20Accident.doc">the original</a> on April 7, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">April 4,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Louis+Slotin&rft_id=http%3A%2F%2Fwww.mphpa.org%2Fclassic%2FNPO%2FSlotin%2520Accident.doc&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span> <span class="cs1-hidden-error error citation-comment">Cite journal requires <code class="cs1-code">|journal=</code> (<a href="/info/en/?search=Help:CS1_errors#missing_periodical" title="Help:CS1 errors">help</a>)</span></span>
</li>
<li id="cite_note-New_Yorker-24"><span class="mw-cite-backlink">^ <a href="#cite_ref-New_Yorker_24-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-New_Yorker_24-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFWellerstein2016" class="citation news cs1">Wellerstein, Alex (May 21, 2016). <a class="external text" href="https://www.newyorker.com/tech/elements/demon-core-the-strange-death-of-louis-slotin?intcid=mod-latest">"The Demon Core and the Strange Death of Louis Slotin"</a>. <i><a href="/info/en/?search=The_New_Yorker" title="The New Yorker">The New Yorker</a></i>. <a class="external text" href="https://web.archive.org/web/20160524022150/http://www.newyorker.com/tech/elements/demon-core-the-strange-death-of-louis-slotin?intcid=mod-latest">Archived</a> from the original on May 24, 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">May 22,</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+New+Yorker&rft.atitle=The+Demon+Core+and+the+Strange+Death+of+Louis+Slotin&rft.date=2016-05-21&rft.aulast=Wellerstein&rft.aufirst=Alex&rft_id=http%3A%2F%2Fwww.newyorker.com%2Ftech%2Felements%2Fdemon-core-the-strange-death-of-louis-slotin%3Fintcid%3Dmod-latest&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
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<li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r999302996"/><cite id="CITEREFWellerstein2016" class="citation web cs1">Wellerstein, Alex (May 23, 2016). <a class="external text" href="https://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/">"The blue flash"</a>. Restricted Data. <a class="external text" href="https://web.archive.org/web/20160524122659/http://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/">Archived</a> from the original on 24 May 2016<span class="reference-accessdate">. Retrieved <span class="nowrap">23 May</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=The+blue+flash&rft.pub=Restricted+Data&rft.date=2016-05-23&rft.aulast=Wellerstein&rft.aufirst=Alex&rft_id=http%3A%2F%2Fblog.nuclearsecrecy.com%2F2016%2F05%2F23%2Fthe-blue-flash%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ADemon+core" class="Z3988"></span></span>
</li>
</ol></div></div>
<h2><span class="mw-headline" id="External_links">External links</span><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="https://en.wikipedia.org/?title=Demon_core&action=edit&section=8" title="Edit section: External links">edit source</a><span class="mw-editsection-bracket">]</span></span></h2>
<ul><li><a href="/info/en/?search=File:Commons-logo.svg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="noviewer" srcset="https://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/18px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/24px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></a> Media related to <a href="https://commons.wikimedia.org/wiki/Category:Demon_core" class="extiw" title="commons:Category:Demon core">Demon core</a> at Wikimedia Commons</li></ul>
<div role="navigation" class="navbox" aria-labelledby="Manhattan_Project" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><style data-mw-deduplicate="TemplateStyles:r992953826">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}.mw-parser-output .infobox .navbar{font-size:100%}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/info/en/?search=Template:Manhattan_Project" title="Template:Manhattan Project"><abbr title="View this template" style=";;background:none transparent;border:none;box-shadow:none;padding:0;;text-decoration:inherit;">v</abbr></a></li><li class="nv-talk"><a href="/info/en/?search=Template_talk:Manhattan_Project" title="Template talk:Manhattan Project"><abbr title="Discuss this template" style=";;background:none transparent;border:none;box-shadow:none;padding:0;;text-decoration:inherit;">t</abbr></a></li><li class="nv-edit"><a class="external text" href="https://en.wikipedia.org/?title=Template:Manhattan_Project&action=edit"><abbr title="Edit this template" style=";;background:none transparent;border:none;box-shadow:none;padding:0;;text-decoration:inherit;">e</abbr></a></li></ul></div><div id="Manhattan_Project" style="font-size:114%;margin:0 4em"><a href="/info/en/?search=Manhattan_Project" title="Manhattan Project">Manhattan Project</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="3"><div id="Timeline"><a href="/info/en/?search=Timeline_of_the_Manhattan_Project" title="Timeline of the Manhattan Project">Timeline</a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Sites</th><td class="navbox-list navbox-odd hlist" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em">
<ul><li><a href="/info/en/?search=Ames_Project" title="Ames Project">Ames</a></li>
<li><a href="/info/en/?search=Calutron" title="Calutron">Berkeley</a></li>
<li><a href="/info/en/?search=Metallurgical_Laboratory" title="Metallurgical Laboratory">Chicago</a></li>
<li><a href="/info/en/?search=Dayton_Project" title="Dayton Project">Dayton</a></li>
<li><a href="/info/en/?search=Hanford_Site" title="Hanford Site">Hanford</a></li>
<li><a href="/info/en/?search=Project_Camel" title="Project Camel">Inyokern</a></li>
<li><a href="/info/en/?search=Project_Y" title="Project Y">Los Alamos</a></li>
<li><a href="/info/en/?search=Montreal_Laboratory" title="Montreal Laboratory">Montreal</a></li>
<li><a href="/info/en/?search=K-25" title="K-25">New York</a></li>
<li><a href="/info/en/?search=Clinton_Engineer_Works" title="Clinton Engineer Works">Oak Ridge</a></li>
<li><a href="/info/en/?search=Salt_Wells_Pilot_Plant" title="Salt Wells Pilot Plant">Salt Wells Pilot Plant</a></li>
<li><a href="/info/en/?search=Trinity_(nuclear_test)" title="Trinity (nuclear test)">Trinity</a></li>
<li><a href="/info/en/?search=Wendover_Air_Force_Base" title="Wendover Air Force Base">Wendover</a></li>
<li><a href="/info/en/?search=P-9_Project" title="P-9 Project">Heavy water sites</a></li></ul>
</div></td><td class="noviewer navbox-image" rowspan="6" style="width:1px;padding:0px 0px 0px 2px"><div><a href="/info/en/?search=File:Nagasakibomb.jpg" class="image" title="The rising mushroom cloud from the Nagasaki "Fat Man" bomb, August 9, 1945"><img alt="The rising mushroom cloud from the Nagasaki "Fat Man" bomb, August 9, 1945" src="https://upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Nagasakibomb.jpg/120px-Nagasakibomb.jpg" decoding="async" width="120" height="143" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Nagasakibomb.jpg/180px-Nagasakibomb.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e0/Nagasakibomb.jpg/240px-Nagasakibomb.jpg 2x" data-file-width="3245" data-file-height="3877" /></a></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Administrators</th><td class="navbox-list navbox-even hlist" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em">
<ul><li><a href="/info/en/?search=Vannevar_Bush" title="Vannevar Bush">Vannevar Bush</a></li>
<li><a href="/info/en/?search=Arthur_Compton" title="Arthur Compton">Arthur Compton</a></li>
<li><a href="/info/en/?search=James_B._Conant" title="James B. Conant">James B. Conant</a></li>
<li><a href="/info/en/?search=Priscilla_Duffield" title="Priscilla Duffield">Priscilla Duffield</a></li>
<li><a href="/info/en/?search=Thomas_Farrell_(general)" class="mw-redirect" title="Thomas Farrell (general)">Thomas Farrell</a></li>
<li><a href="/info/en/?search=Leslie_Groves" title="Leslie Groves">Leslie Groves</a></li>
<li><a href="/info/en/?search=John_Lansdale_Jr." title="John Lansdale Jr.">John Lansdale</a></li>
<li><a href="/info/en/?search=Ernest_Lawrence" title="Ernest Lawrence">Ernest Lawrence</a></li>
<li><a href="/info/en/?search=James_C._Marshall" title="James C. Marshall">James Marshall</a></li>
<li><a href="/info/en/?search=Franklin_Matthias" title="Franklin Matthias">Franklin Matthias</a></li>
<li><a href="/info/en/?search=Dorothy_McKibbin" title="Dorothy McKibbin">Dorothy McKibbin</a></li>
<li><a href="/info/en/?search=Kenneth_Nichols" title="Kenneth Nichols">Kenneth Nichols</a></li>
<li><a href="/info/en/?search=J._Robert_Oppenheimer" title="J. Robert Oppenheimer">Robert Oppenheimer</a></li>
<li><a href="/info/en/?search=William_Sterling_Parsons" title="William Sterling Parsons">Deak Parsons</a></li>
<li><a href="/info/en/?search=William_R._Purnell" title="William R. Purnell">William Purnell</a></li>
<li><a href="/info/en/?search=Frank_Spedding" title="Frank Spedding">Frank Spedding</a></li>
<li><a href="/info/en/?search=Charles_Allen_Thomas" title="Charles Allen Thomas">Charles Thomas</a></li>
<li><a href="/info/en/?search=Paul_Tibbets" title="Paul Tibbets">Paul Tibbets</a></li>
<li><a href="/info/en/?search=William_L._Uanna" title="William L. Uanna">Bud Uanna</a></li>
<li><a href="/info/en/?search=Harold_Urey" title="Harold Urey">Harold Urey</a></li>
<li><a href="/info/en/?search=Stafford_L._Warren" title="Stafford L. Warren">Stafford Warren</a></li>
<li><a href="/info/en/?search=Ed_Westcott" title="Ed Westcott">Ed Westcott</a></li>
<li><a href="/info/en/?search=Roscoe_Charles_Wilson" title="Roscoe Charles Wilson">Roscoe Wilson</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Scientists</th><td class="navbox-list navbox-odd hlist" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em">
<ul><li><a href="/info/en/?search=Luis_Walter_Alvarez" title="Luis Walter Alvarez">Luis Alvarez</a></li>
<li><a href="/info/en/?search=Robert_Bacher" title="Robert Bacher">Robert Bacher</a></li>
<li><a href="/info/en/?search=Hans_Bethe" title="Hans Bethe">Hans Bethe</a></li>
<li><a href="/info/en/?search=Aage_Bohr" title="Aage Bohr">Aage Bohr</a></li>
<li><a href="/info/en/?search=Niels_Bohr" title="Niels Bohr">Niels Bohr</a></li>
<li><a href="/info/en/?search=Norris_Bradbury" title="Norris Bradbury">Norris Bradbury</a></li>
<li><a href="/info/en/?search=James_Chadwick" title="James Chadwick">James Chadwick</a></li>
<li><a href="/info/en/?search=John_Cockcroft" title="John Cockcroft">John Cockcroft</a></li>
<li><a href="/info/en/?search=Charles_Critchfield" title="Charles Critchfield">Charles Critchfield</a></li>
<li><a href="/info/en/?search=Harry_Daghlian" title="Harry Daghlian">Harry Daghlian</a></li>
<li><a href="/info/en/?search=Enrico_Fermi" title="Enrico Fermi">Enrico Fermi</a></li>
<li><a href="/info/en/?search=Richard_Feynman" title="Richard Feynman">Richard Feynman</a></li>
<li><a href="/info/en/?search=Val_Logsdon_Fitch" title="Val Logsdon Fitch">Val Fitch</a></li>
<li><a href="/info/en/?search=James_Franck" title="James Franck">James Franck</a></li>
<li><a href="/info/en/?search=Klaus_Fuchs" title="Klaus Fuchs">Klaus Fuchs</a></li>
<li><a href="/info/en/?search=Maria_Goeppert_Mayer" title="Maria Goeppert Mayer">Maria Goeppert Mayer</a></li>
<li><a href="/info/en/?search=George_Kistiakowsky" title="George Kistiakowsky">George Kistiakowsky</a></li>
<li><a href="/info/en/?search=George_Koval" title="George Koval">George Koval</a></li>
<li><a href="/info/en/?search=Willard_Libby" title="Willard Libby">Willard Libby</a></li>
<li><a href="/info/en/?search=Joseph_L._McKibben" class="mw-redirect" title="Joseph L. McKibben">Joseph L. McKibben</a></li>
<li><a href="/info/en/?search=Edwin_McMillan" title="Edwin McMillan">Edwin McMillan</a></li>
<li><a href="/info/en/?search=Mark_Oliphant" title="Mark Oliphant">Mark Oliphant</a></li>
<li><a href="/info/en/?search=Norman_Foster_Ramsey_Jr." title="Norman Foster Ramsey Jr.">Norman Ramsey</a></li>
<li><a href="/info/en/?search=Isidor_Isaac_Rabi" title="Isidor Isaac Rabi">Isidor Isaac Rabi</a></li>
<li><a href="/info/en/?search=James_Rainwater" title="James Rainwater">James Rainwater</a></li>
<li><a href="/info/en/?search=Bruno_Rossi" title="Bruno Rossi">Bruno Rossi</a></li>
<li><a href="/info/en/?search=Glenn_T._Seaborg" title="Glenn T. Seaborg">Glenn Seaborg</a></li>
<li><a href="/info/en/?search=Emilio_Segr%C3%A8" title="Emilio Segrè">Emilio Segrè</a></li>
<li><a href="/info/en/?search=Louis_Slotin" title="Louis Slotin">Louis Slotin</a></li>
<li><a href="/info/en/?search=Henry_DeWolf_Smyth" title="Henry DeWolf Smyth">Henry DeWolf Smyth</a></li>
<li><a href="/info/en/?search=Leo_Szilard" title="Leo Szilard">Leo Szilard</a></li>
<li><a href="/info/en/?search=Edward_Teller" title="Edward Teller">Edward Teller</a></li>
<li><a href="/info/en/?search=Stanislaw_Ulam" title="Stanislaw Ulam">Stanisław Ulam</a></li>
<li><a href="/info/en/?search=John_von_Neumann" title="John von Neumann">John von Neumann</a></li>
<li><a href="/info/en/?search=John_Archibald_Wheeler" title="John Archibald Wheeler">John Wheeler</a></li>
<li><a href="/info/en/?search=Eugene_Wigner" title="Eugene Wigner">Eugene Wigner</a></li>
<li><a href="/info/en/?search=Robert_R._Wilson" title="Robert R. Wilson">Robert Wilson</a></li>
<li><a href="/info/en/?search=Leona_Woods" title="Leona Woods">Leona Woods</a></li>
<li><a href="/info/en/?search=Chien-Shiung_Wu" title="Chien-Shiung Wu">Chien-Shiung Wu</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Operations</th><td class="navbox-list navbox-even hlist" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em">
<ul><li><a href="/info/en/?search=Alsos_Mission" title="Alsos Mission">Alsos Mission</a></li>
<li><a href="/info/en/?search=Atomic_bombings_of_Hiroshima_and_Nagasaki" title="Atomic bombings of Hiroshima and Nagasaki">Bombings of Hiroshima and Nagasaki</a></li>
<li><a href="/info/en/?search=Operation_Crossroads" title="Operation Crossroads">Operation Crossroads</a></li>
<li><a href="/info/en/?search=Operation_Peppermint" title="Operation Peppermint">Operation Peppermint</a></li>
<li><a href="/info/en/?search=Project_Alberta" title="Project Alberta">Project Alberta</a></li>
<li><a href="/info/en/?search=Silverplate" title="Silverplate">Silverplate</a></li>
<li><a href="/info/en/?search=509th_Composite_Group" title="509th Composite Group">509th Composite Group</a></li>
<li><i><a href="/info/en/?search=Enola_Gay" title="Enola Gay">Enola Gay</a></i></li>
<li><i><a href="/info/en/?search=Bockscar" title="Bockscar">Bockscar</a></i></li>
<li><i><a href="/info/en/?search=The_Great_Artiste" title="The Great Artiste">The Great Artiste</a></i></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Weapons</th><td class="navbox-list navbox-odd hlist" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em">
<ul><li><a href="/info/en/?search=Fat_Man" title="Fat Man">Fat Man</a></li>
<li><a href="/info/en/?search=Little_Boy" title="Little Boy">Little Boy</a></li>
<li><a href="/info/en/?search=Pumpkin_bomb" title="Pumpkin bomb">Pumpkin bomb</a></li>
<li><a href="/info/en/?search=Thin_Man_(nuclear_bomb)" title="Thin Man (nuclear bomb)">Thin Man</a></li></ul>
</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related topics</th><td class="navbox-list navbox-even hlist" style="text-align:left;border-left-width:2px;border-left-style:solid;width:100%;padding:0px"><div style="padding:0em 0.25em">
<ul><li><a href="/info/en/?search=Atomic_Energy_Act_of_1946" title="Atomic Energy Act of 1946">Atomic Energy Act of 1946</a></li>
<li><a href="/info/en/?search=Bismuth_phosphate_process" title="Bismuth phosphate process">Bismuth phosphate process</a></li>
<li><a href="/info/en/?search=British_contribution_to_the_Manhattan_Project" title="British contribution to the Manhattan Project">British contribution</a></li>
<li><a href="/info/en/?search=Chicago_Pile-1" title="Chicago Pile-1">Chicago Pile-1</a></li>
<li><a class="mw-selflink selflink">Demon core</a></li>
<li><a href="/info/en/?search=Einstein%E2%80%93Szil%C3%A1rd_letter" title="Einstein–Szilárd letter">Einstein–Szilárd letter</a></li>
<li><a href="/info/en/?search=Franck_Report" title="Franck Report">Franck Report</a></li>
<li><a href="/info/en/?search=Interim_Committee" title="Interim Committee">Interim Committee</a></li>
<li><a href="/info/en/?search=Oppenheimer_security_hearing" title="Oppenheimer security hearing">Oppenheimer security hearing</a></li>
<li><a href="/info/en/?search=Plutonium" title="Plutonium">Plutonium</a></li>
<li><a href="/info/en/?search=Quebec_Agreement" title="Quebec Agreement">Quebec Agreement</a></li>
<li><a href="/info/en/?search=RaLa_Experiment" title="RaLa Experiment">RaLa Experiment</a></li>
<li><a href="/info/en/?search=S-1_Executive_Committee" title="S-1 Executive Committee">S-1 Executive Committee</a></li>
<li><a href="/info/en/?search=S-50_(Manhattan_Project)" title="S-50 (Manhattan Project)">S-50 Project</a></li>
<li><a href="/info/en/?search=Smyth_Report" title="Smyth Report">Smyth Report</a></li>
<li><a href="/info/en/?search=Uranium" title="Uranium">Uranium</a></li>
<li><a href="/info/en/?search=USS_Indianapolis_(CA-35)" title="USS Indianapolis (CA-35)">USS <i>Indianapolis</i></a></li>
<li><a href="/info/en/?search=X-10_Graphite_Reactor" title="X-10 Graphite Reactor">X-10 Graphite Reactor</a></li></ul>
</div></td></tr><tr><td class="navbox-abovebelow" colspan="3"><div><img alt="Category" src="https://upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" title="Category" width="16" height="16" class="noviewer" srcset="https://upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /> <a href="/info/en/?search=Category:Manhattan_Project" title="Category:Manhattan Project">Manhattan Project</a></div></td></tr></tbody></table></div>
<div class="noprint metadata navbox" role="navigation" aria-label="Portals" style="font-weight:bold;padding:0.4em 2em"><ul style="margin:0.1em 0 0"><li style="display:inline"><span style="display:inline-block;white-space:nowrap"><span style="margin:0 0.5em"><a href="/info/en/?search=File:Newton%27s_reflecting_telescope.jpg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Newton%27s_reflecting_telescope.jpg/19px-Newton%27s_reflecting_telescope.jpg" decoding="async" width="19" height="21" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Newton%27s_reflecting_telescope.jpg/29px-Newton%27s_reflecting_telescope.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Newton%27s_reflecting_telescope.jpg/37px-Newton%27s_reflecting_telescope.jpg 2x" data-file-width="1140" data-file-height="1276" /></a></span><a href="/info/en/?search=Portal:History_of_Science" class="mw-redirect" title="Portal:History of Science">History of Science portal</a></span></li><li style="display:inline"><span style="display:inline-block;white-space:nowrap"><span style="margin:0 0.5em"><a href="/info/en/?search=File:Radioactive.svg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Radioactive.svg/24px-Radioactive.svg.png" decoding="async" width="24" height="21" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Radioactive.svg/36px-Radioactive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Radioactive.svg/48px-Radioactive.svg.png 2x" data-file-width="512" data-file-height="446" /></a></span><a href="/info/en/?search=Portal:Nuclear_technology" title="Portal:Nuclear technology">Nuclear technology portal</a></span></li><li style="display:inline"><span style="display:inline-block;white-space:nowrap"><span style="margin:0 0.5em"><a href="/info/en/?search=File:Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/18px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png" decoding="async" width="18" height="21" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/28px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/37px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 2x" data-file-width="530" data-file-height="600" /></a></span><a href="/info/en/?search=Portal:Physics" title="Portal:Physics">Physics portal</a></span></li><li style="display:inline"><span style="display:inline-block;white-space:nowrap"><span style="margin:0 0.5em"><a href="/info/en/?search=File:Heinkel_He_111_during_the_Battle_of_Britain.jpg" class="image"><img alt="" src="https://upload.wikimedia.org/wikipedia/commons/thumb/8/82/Heinkel_He_111_during_the_Battle_of_Britain.jpg/24px-Heinkel_He_111_during_the_Battle_of_Britain.jpg" decoding="async" width="24" height="20" srcset="https://upload.wikimedia.org/wikipedia/commons/thumb/8/82/Heinkel_He_111_during_the_Battle_of_Britain.jpg/36px-Heinkel_He_111_during_the_Battle_of_Britain.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/82/Heinkel_He_111_during_the_Battle_of_Britain.jpg/48px-Heinkel_He_111_during_the_Battle_of_Britain.jpg 2x" data-file-width="800" data-file-height="676" /></a></span><a href="/info/en/?search=Portal:World_War_II" title="Portal:World War II">World War II portal</a></span></li></ul></div>
' |
Whether or not the change was made through a Tor exit node (tor_exit_node) | false |
Unix timestamp of change (timestamp) | 1632887636 |