A Brief History of: The Demon Core (Short Documentary)

[Music] this seemingly harmless Bowl fully uninitiated looks like any old piece of metal a cannonball or a small wrecking ball maybe but if you had the misfortune to handle this incorrectly you would most certainly have a painful and horrible death sadly two people had such an experience and more would die prematurely of cancer over subsequent decades and arguably the two instants showed how you can't take for granted material with a potential of going supercritical at the drop of a hat unsurprisingly the item in question would gain a named a demon core but what was this innocuous-looking item if his subject has been covered before by someone I know but I found this story really interesting and I had to do a video about it I've included the link in the video description if you'd like to check it out once you finish watching this video like many of my atomic videos our story starts during the Second World War and the Manhattan Project a demon core or Rufus as it was originally nicknamed was intended to be used in a third atomic bomb to be dropped on Japan her weapon fat was never needed on the 15th of August Japan surrendered after two atomic bombs being detonated over Hiroshima and Nagasaki the core was similar to the one used in the fat man bomb dropped on Nagasaki consisting of free pieces to plutonium gallium hemispheres separated by a ring the plutonium core was refined and hot pressed into its ominous severe achill shape at Hanford and shipped to Los Alamos laboratory for preparation for use in an implosion type bomb once assembled it was designed to be 5% below critical mass leaving the course somewhat safe however 5% was to ensure that when needed it could be used to make a very large explosion easily but one deadly side effect was that this left very little margin for error you see once the core went critical it would be in a perfect state of equilibrium no increase or decrease in power however one in many different factors could send the core into super criticality creating and sustaining a chain reaction until it ever settled at a new criticality level and increase power or explode needless to say both outcomes would be a bit of a bad thing the scientists at a Manhattan Project found themselves with his surplice piece of weapons-grade material and I did what most scientists would do study and push the boundaries however so many experiments were outright reckless and misleads us to the cause first victim hairy deadly in a 24-year old physicist from New London Connecticut was working on the core on a 21st of August 1945 deadly enhan on the staff of the Manhattan Project since 1944 joining while still a graduate student on a fateful day dag lien was making a neutron reflector around the core of tungsten carbide a new chin reflector funnily enough is designed to reflect neutrons back into a subcritical mass making the material critical it can also increase nuclear fission a critical mass is capable of the neutral reflector experiment was being performed alone apart from private to Robert J Henley who was sat behind desk four meters away on guard duty whilst undertaking the experiment degli and noticed that the addition of a file tungsten brick would render the core supercritical he withdrew to brick with his hand in doing so accidentally dropping it onto the pile this was all that was needed for the court to go prompt critical immediately he tried to remove the brick by knocking it off and was unsuccessful instead he quickly disassembled a pile but by this time he had absorbed 510 REM of neutron radiation his fate was sealed he received intensive care but would fall into a coma and pass away 25 days after the incident the first known death linked to a criticality accident his hands shown here had the skin burned off from the event degli his body was transported back to New London to be buried in Cedar Grove a tragic accident that led to Douglas death sparked review of safety regulations within the project one of the major changes was that any similar experiment would require two personnel and two instruments capable of monitoring and alerting Neutron counts these new rules put in place were thought to reduce the risk of a criticality accident however this would not be the case when it came to the soon-to-be nicknamed demon core just nine months would go by until a core experienced its second criticality accident do an experiment nicknamed tickling the Dragons tail so named due to the apparent disregard to standard safety practices Louis Slaton was a 35 year old Canadian physicist and chemist having worked on a Manhattan project since 1942 he worked on experiments with uranium and plutonium cause to assess their critical mass amount needless to say he was experienced but possibly he had become complacent plotting in the heads become quite the showman when doing experiments and this had not changed leading up to his planned exit for the Manhattan Project Slauson had become increasingly unhappy in his involvement in the project however he could not leave into a replacement have been trained up he had been quoted saying I am one of the few people left here who are experienced bomb putted together nurse after leaving the project Slaton had planned to return to teaching this brings us to the 21st of May 1946 and at around 3 p.m. Slaton was preparing to demonstrate an experiment to his replacement 36 year old Alvin Seagraves the experiment would involve two spheres of beryllium the two parts put together around the core would create a neutral reflector an experiment was used to create one of the first steps in a fission reaction one half of the beryllium sphere had a small hole in the top of it to allow an operator to hold on to it to enable manual lowering and shims were used to prevent the two halves from touching which would cause a criticality accident machines made a rudimentary albeit effective method of protection however Slaton had developed a unique modification to the experiment he instead of using shims would use a single flat blade screwdriver to separate the two half spheres meaning that during an experiment both hands of the operator would be used one holding the top half by the hole with their thumb and the other spacing the sphere with the tip of the screwdriver Slauson had done the experiment in this fashion several times two observers even reportedly prompting Enrico Fermi to tell slot in that he'd be dead within a year if he carried on using this dangerous method so well-known was the danger of using a screwdriver for the experiment got the nickname a tickling metalia dragon I think we can see where this is going June experiment around 3:20 p.m. be inevitable happened as the flat head screwdriver slipped in slot in his right hand causing the top half sphere to close over the core the core went supercritical causing the air around it to ionize making an eerie blue glow the intense burst of neutron radiation was released into the room a slot in experience a sour taste in his mouth slot in his left hand started to burn immediately causing him to throw his arm in the air in doing so knocking off the top sphere onto the floor ending the criticality incident in total only last in a couple of seconds Slaton had prevented any further reaction and his position over the core had inadvertently shielded the other occupants in the room including Alvin who had received a high but not deadly dose of radiation however this ensured that Slaton was not so lucky Slaton vomited after leaving the laboratory and was immediately hospitalized his body was covered in blisters and had experienced burns on some of his internal organs in what a doctor would describe as free dimentional sunburn seven days after exposure Slaton experienced extreme mental confusion and after his lips went blue he was placed inside an oxygen tent eventually slipping into a coma he died of his exposure with his parents at his side after nine days despite having received intensive care three other witnesses the experiment would remain in hospital after slaughtering tragic death Alvin graves developed symptoms of acute radiation sickness and all those surviving would live with chronic neurological and vision problems he will continue to work in nuclear testing until his death in 1965 after a heart attack whatever personnel member would die around the same time as graves of leukemia however it is impossible to tell for certain due to the demon core also the guard on duty June Begley and experiment would die at the age of 62 also of leukemia sadly the core took the lives of two very talented scientists but it just shows how deadly radiation can be and how complacency even with the most skilled of operators is not the most ideal thing around dangerous material the cause destination was going to be intended for operation crossroads after the experiments however due to the slaughter and criticality incident some time was needed to reevaluate the cause effectiveness for use in a bomb ironically it would be due to its criticality incidents but the core would not be used for weapons detonation instead it was melted down for use in other cause due to the criticality accidents no more experiments would be done by hand instead using remotely controlled machines allowing the operator to be located in a safe room away from radiation however this would not completely remove casualties from criticality accidents but they will be subjects for future videos thanks for watching I hope you enjoyed the video if you did leave a like if you have any suggestions for future videos let me know in the comments if you'd like to support the channel financially then you're in luck as I have a patreon and a link is in the description and officer to say is thank you for watching

Channel: Plainly Difficult

Views: 6,681,340

Keywords: demon core, los alamos, plainly difficult, louis slotin, harry daghlian, education, manhatten project, nuclear, atomic history

Id: VE8FnsnWz48

Length: 10min 22sec (622 seconds)

Published: Tue May 21 2019

Reddit Comments

[u/barconr]

A very good recounting of the story here: http://blog.nuclearsecrecy.com/2016/05/23/the-blue-flash/

A deeply unpleasent way to go.

[u/AngelofServatis]

Heres a wiki page with more details on other “Criticality accidents ” There have been about 14 recorded incidents of people being exposed to extreme levels of radiation. One of the most severe ones it lists (as far as level of REM exposure to a single human) states one dude got exposed to over 3,500-4,900 REM (thats more than 7 times what Dhaglian was exposed to) There was another that said a guy was exposed to about 4,850 REM

I Just spent the last 3 hours researching them, really fascinating stuff even though a lot of the scientific jargon is hard to understand.