The beginning of the atomic era. Demon core

In the summer of 1946, a 27-kiloton nuclear bomb in TNT was detonated over the Bikini Atoll. The purpose of the test, codenamed Able, was ships located in the lagoon, with a "crew" of experimental animals - pigs, goats and rats. However, long before the test, the victims of this bomb were two nuclear physicists who conducted experiments with the plutonium charge of the bomb. He received notoriety and his own name - Demon core.


On Habré earlier, a fairly detailed description of the stages of the Manhattan project was published, the result of which was the creation and combat use of atomic bombs of two types: uranium and plutonium. In both cases, the same physical principle is used for the explosion - the creation of a critical mass of a radioactive substance to start a chain reaction. The first type of bomb was made quite simple. It carried out a quick connection of two parts of the uranium charge, while the total mass became more critical and an explosion occurred - the so-called “gun method”. The second type, in its extremely simplified form, was a plutonium sphere, covered outside with ordinary explosives. With its undermining the ball shrank and turned into a critical state: the mass of the substance remained unchanged, the density increased. The gun method for plutonium was not suitable because of its high level of radioactivity and the danger of an explosion at the bomb assembly stage.
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Without going deep into the rather complex construction of the plutonium bomb (this will probably be a separate article), we mention only one detail: a neutron-reflecting substance was used as one of the shells. This was done in order to increase the efficiency of the bomb and reduce the mass of plutonium required for the explosion: the neutrons remaining “inside” the charge participated in the chain reaction, splitting the nuclei of the plutonium, and the more they were, the more intense the reaction went.

We did one thing: we went to a room where a small silver ball was lying on the edge of a narrow stand. You could put your hand on it. The ball was warm. He was radioactive. It was plutonium ... It was a new element obtained by man, a substance that never existed on earth before, except perhaps for a very short period at the very beginning. And here it is, isolated and radioactive, with all the amazing properties. And we got it. And so he was tremendously valuable. (Hereinafter quotes belong to the great Richard Feynman.)

“A small silver ball” weighed just over 6 kilograms and was 3.5 inches in diameter - easy to imagine, comparing it with a regular floppy disk. It would hardly be a good idea to carry him in your pocket, but it was quite possible to be in the same room and even touch it without harm to health. Plutonium was produced at Handford, WA. It was there that the substance was obtained for the first ever atomic explosion - Trinity, for the bomb dropped on Nagasaki and, finally, for the Devil's nucleus.

The people at Oak Ridge did not know where the uranium was to be used - they just knew that this and that should be done ... But the people “below” did not even know what they were doing. However, Segre insisted that people from Oak Ridge would never be able to perform the tests correctly, and the whole idea would fly into the tube. Therefore, in the end, he went to look at their work and, as he walked through the territory, he suddenly saw that they were taking a huge container of water — green water — that is, a solution of uranium nitrate. He said:
- Wow! And what, are you going to handle this water in the same manner and when will the uranium be purified? Is this what you are going to do?
They stopped:
- Of course, why not?
“Doesn't everything explode?”
- What? Will blow up?

Researchers, scientists, simple workers of that time were pioneers in a new, uncharted territory. It is today we see nuclear power plants controlled by computers, systems of protection and control, people in suits-suits. At the same time, laboratories were more like locksmiths, and safety rules were developed along with new and new experiments, often very dangerous ones. Two of them resulted in human sacrifice.

August 21, 1945. Harry Deglin, Jr.

The first incident with the Devil's core occurred two weeks after the destruction of Hiroshima and Nagasaki. Harry Deglien Jr. conducted an experiment to build a neutron-reflecting shell around the Nucleus. It consisted of tungsten carbide bricks - this alloy is used to make bullets and shells, drills, balls for ballpoint pens and even wedding rings. The procedure consisted in the gradual addition of bricks, forming a “well” around the Core, as a result of which it was brought to a state close to critical.

On the morning of August 21, Deglien conducted two experiments, building "wells" of bricks of different sizes. The next assembly was scheduled for the next morning, but the physicist decided to carry it out alone that evening, in violation of the established rules. In the laboratory there was only a security guard who greeted Harry and delved into reading the newspaper.



Dglien built a well of four layers of bricks, controlling the radiation of the Core with a counter. On the next layer, the meter showed a sharp increase in the level of radiation, which meant that the whole structure was in a state close to critical. The scientist began to remove the brick and suddenly dropped it directly to the center of the assembly. The clock was 9 hours 55 minutes in the evening.



The guard sat with his back to Dglien at a distance of about 5 meters and heard the counter crack, the sound of a falling brick, and then saw a flash of light. Turning, he saw the scientist, frozen, standing next to the assembly, trying to assess the situation. Dglien dismantled the structure, transferring it to a safe state, but by this time he had already received a total dose of radiation of about 600 X-rays. The hands suffered the most: in his left hand the physicist held a brick until it fell, with his right pushed him from the top of the Core. Doses of hands exposure ranged from 15 to 40 thousand rem. The link (warning: the photo is not pleasant) you can see the state of the right hand nine days after the incident - in simple terms, it was burned by radiation.

After 26 days, Deglien passed away. The efforts of physicians did not bring results and with a dose of radiation that many times exceeded the lethal level, they were useless. The incident was published a short article in the New York Times, where it was alleged that the physicist died of chemical burns.

May 21, 1946 Louis Slotin

One of Déglien's colleagues and friends who worked with him and visited him at the hospital was the Canadian physicist Louis Slotin. In Los Alamos, he also engaged in dangerous experiments to bring radioactive charges to a state close to critical. Slotin also took part in the assembly of Trinity - the first atomic bomb detonated in the New Mexico desert on July 16, 1945. During his work, he became an extremely experienced and unique specialist in his field. It should be noted that after the end of the Second World War, Slotin expressed hostility towards the testing of atomic weapons. He planned to continue research in the peaceful areas of radiobiology and biophysics.

In the new experiment, the Devil's core was placed in a shell of two beryllium hemispheres. Beryllium, like tungsten carbide, is a neutron reflector. On the afternoon of May 21, in the presence of seven colleagues, Slotin placed the Core in the lower hemisphere and covered it with the upper hemisphere. There should be a small gap between the reflectors, for which special gaskets were usually used. But this time there were none, Slotin held the upper hemisphere with his left hand, and in his right hand he held a screwdriver that did not allow the hemispheres to connect.



What happened next - now it is not difficult to guess. At 3:30 pm the screwdriver slipped off and the upper hemisphere fell onto the Core. People in the room saw the blue glow of ionized air and felt the heat wave emanating from the Core. Slotin felt a strong burning sensation in his left hand and instinctively withdrew it, removing the upper hemisphere and thus stopping the chain reaction. However, he already knew exactly what happened irreparable. The radiation dose received by the physicist was about 2100 x-rays. Colleagues who were nearby, received smaller doses, Alvin Graves, who was next to the Core, suffered the most. He had to change his position in Slotina. As a result of the irradiation, he became blind, which did not prevent him from subsequently becoming the leader of many ground-based nuclear tests conducted by the United States in the 1950s.

Slotin died 9 days later in the same hospital and in the same room where Deglien had died before.

Information about the second incident was classified for some time. Later, Slotin was introduced as a hero who saved his colleagues at the cost of his life. The editor of the local newspaper Los Alamos Times devoted verses to his memory (translated by A. Murashova):

God bless you, great scientist!
In ordinary life, we knew only the breadth of your mind,
And only in the crucible of mortal trials
Your soul has opened to us.


However, what happened was entirely his fault. The devil's core for the second time did not forgive the safety violations and the rules of the experiment.

After the incidents, all experiments with the direct participation of people were discontinued. Further tests of critical states were carried out using remotely controlled devices.

June 1, 1946

Devilish core, finally ceased to exist. Ahead were thousands of nuclear tests in the air, on the ground, under the water and underground, in space ...

Afterword, it is the preface. July 16, 1945

When it was all over, terrible excitement arose in Los Alamos. Everyone was having parties, and we were running everywhere. I hid in a corner of the jeep and beat the drum and all that. But one person, I remember, Bob Wilson, was sitting down depressed and indifferent.
- Why are you depressed? - I asked him.
He said:
“What we did was terrible.”
I was surprised:
- But you yourself started it. It was you who involved us all.
Do you understand what happened to me, what happened to all of us? We started with good intentions, then worked hard to complete something important. It is a pleasure, it is very exciting. And you stop thinking, you know, you just stop. Bob Wilson was the only one who was still thinking about it at that moment.

Links

Demon core on Wikipedia
Operation Crossroads
Harry Dugien Memorial Site
Louis Slotina Memorial Site