In August 1945, the United States dropped two atomic bombs on Hiroshima and Nagasaki, Japan, causing more than 200,000 casualties. This was the first time in human history that nuclear weapons were used in a war.
In fact, there is also a third atomic bomb, which will be dropped on Kokura, Japan on August 19. Manhattan Project invested a lot of resources in the manufacture of enriched uranium and plutonium. By the summer of 1945, it had produced enough materials to assemble three atomic bombs, and the fourth core was also being manufactured.
However, Japan collapsed quickly before the huge power of the atomic bomb. The emperor announced an unconditional surrender on August 15, and the Second World War ended.
So the third atomic bomb lost its usefulness, and hundreds of thousands of lives were lucky enough to survive. The plutonium core of the atomic bomb nicknamed "Rufus" was also disassembled and sent to Los Alamos National Laboratory for supercritical numerical testing.
This plutonium ball is 9 cm in diameter and 6.2 kg in weight. It is usually in a subcritical state. Nuclear physicists plan to wrap it with tungsten carbide blocks so that the neutrons produced by fission will be reflected back, thereby further increasing the reaction speed, bringing the plutonium core close to the critical edge, and the critical mass can be measured.
But this is also very risky. The reflected neutron flow cannot be too much, otherwise the plutonium core will enter a supercritical state to initiate a chain reaction, although it will not be like an atomic bomb due to other conditions. It explodes, but it also emits blue light releases huge radiant energy.
They also know the high risk of the experiment, so they jokingly call it the "cracking dragon's tail". Just like the tail of a sleeping dragon, if the monsters are unfortunately angered, they may be scorched by the radioactive dragon fire at any time.
And this is exactly what happened to Harry Daglian Jr. and Louis Slotin.
At that time, the protection standards of the Alamos Laboratory were still relatively lax,Many scientists and engineers work directly in the radiation environment, so the physicists involved in the plutonium core test will also perform these experiments manually.
Little Harry Dalglian
On the evening of August 21, 1945, Dalglian, who was off work, returned to the laboratory after dinner. Because he suddenly had some inspiration, he came alone to tickle "Dragon's Tail". There are no other scientists around him, only a security guard is on duty.
Daglian wrapped the plutonium core with tungsten carbide blocks as usual, and carefully recorded the test values. As the core gets closer and closer to the critical state, his movements become slower and slower.
When he picked up the last piece of tungsten carbide, his hand suddenly slipped. The tungsten piece fell on the core and blocked the neutron overflow channel. The plutonium core suddenly reached a supercritical state-blue burst flash, a deadly nuclear radiation moment Release it.
Daglian was taken aback, and it was too late to remove the tungsten block immediately. The security guard on the side didn't even know anything. After hearing the noise, he came over and inspected. Daglian hurriedly shouted at him: Go away, go away!
After he was sent to the hospital, he developed severe radiation sickness symptoms, nausea and vomiting, arms swelling, skin ulcers, and severe internal organ damage. Daglian died after 25 days of struggling with the disease. He donated his body to the hospital to study the effects of massive nuclear radiation on the human body.
After Daglian’s accident, the laboratory raised its safety standards to prevent the tragedy from happening again, but the tragedy still happened.
In 1946, Daglian’s colleague Louis Slotin took over the test experiment and the laboratory changed its location.
Slotin is an outstanding physicist who participated in the assembly of the world's first nuclear bomb "Gadget", but he is also very reckless and is known for his boldness to take risks and ignore danger.
Louis Slotin is holding the nuclear bomb device
He improved the test method, placing the plutonium core in two hemispheres, one large and one small.The upper part is beryllium material, and the lower part is aluminum material. When the upper cover of beryllium is slowly buckled down, neutrons can be reflected to make the plutonium core close to the critical state.
But the upper cover of beryllium cannot be put down completely, a gap should be left between the two hemispheres to prevent too much neutron reflection to trigger a chain reaction. Therefore, the metal gasket should be placed between the two hemispheres in the standard process to prevent the upper and lower covers from being completely closed.
But Slotin found it too troublesome. He removed the gasket and only used a simple flat-blade screwdriver to control the gap between the upper and lower covers, and manually adjusted it as needed.
He is quite proficient in this technology, and he is famous among his colleagues as "scraping dragon's tail". However, the physics magnate Enrico • Fermi warned him: if you "scrape dragon's tail" again like this, you will Died within a year.
Slotin was young and vigorous. He ignored the warnings of his predecessors and continued to use his unique skills to carry out experiments. He did more than a dozen times before and after without failing.
On May 21, 1946, Slotin and seven colleagues started the test again. He used a screwdriver to hold the beryllium hemisphere and carefully put it down, while recording the test data.
Unexpectedly, a colleague went to get the record form and accidentally knocked over the coffee cup on the table. The cup fell to the ground and shattered, and Slotin's hands shook with fright...
It's over! The plutonium core of the upper and lower covers was put into a supercritical state instantly, a burst of bright blue light flashed, and a powerful radiation shock wave hit immediately.
Slotin's heart sank suddenly, and he broke the shell with his hands in spite of the high temperature, but it was too late. Although the reaction has stopped, he has been exposed to extremely high doses of nuclear radiation.
He was leaning over the core of the reactor, absorbing most of the nuclear radiation, and saving other people in the laboratory with his body.
Several colleagues ran out of the room in fright, Slotin called them back, marked their locations with chalk, and calculated the amount of radiation they received.The result is not serious.
Then he said: Okay, so be it. He had visited Dalglian a few months ago and knew he was dead.
Slotin received more than 1,000 rads of nuclear radiation in just a few seconds, surpassing the highest dose anyone had ever received. You should know that when the Hiroshima atomic bomb exploded , the radiation dose was only 400 rad at a distance of 1000 meters from the explosion point.
rays destroyed the cells in the body. A few minutes later, he became poisoned. The talented physicist died 9 days later at the age of 35. Several other colleagues also died of various radiation complications two to three decades later.
After taking the lives of two scientists, people no longer call it "Rufus". This plutonium core has received a notorious nickname-"Demon Core".
Demon Core
Alamos Laboratories decided to formulate new operating procedures to stop the demon's atrocities. From then on, scientists could only use remote control devices to manipulate the radioactive core from a few hundred meters away.
In the 1946 "Operation Crossroads" nuclear experiment, the military planned to explode this "demon core", but it was not implemented for various reasons.
It was finally melted and recycled and merged into other cores, leaving only this horrible history to remind people that we must always be alert to nuclear demons and never let it harm the world.
Talk about original text in Hefeng, welcome to pay attention. The picture comes from the Internet, personal opinion, for reference only.
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