We already had a topic about how "The screwdriver became a fuse against a nuclear explosion", but I suggest reading about this incident in a little more detail.
The experiment in question began on May 21, 1946, in a secret laboratory three miles outside Los Alamos, New Mexico, where the atomic bomb was first created. Luis Zlotin, a Canadian physicist, showed his colleagues how you can bring the nucleus of an atomic bomb to a subcritical state.
This is how it happened …
The core itself "emitted heat" (radioactive) and was an ordinary metal hemisphere with a plutonium cone in the center. They were going to use it as material for the creation of another atomic bomb, but after the bombing of Nagasaki, this need disappeared - the war was over.
In those days, Zlotin was the most outstanding expert in plutonium handling. A year earlier, he was working on the creation of an atomic bomb, and one of the photographers even captured him in the process - in an unbuttoned shirt and welding goggles, he stood next to a bomb, in which all the insides were literally turned out. Then the manufacture of atomic bombs was mostly associated with such "handicraft production", almost everything was done by hand.
The experiment itself was simple, and consisted in the following: Zlotin took a hemisphere of beryllium, which was a neutron reflector, and slowly lowered it onto the nucleus, stopping exactly at the moment when the hemisphere was almost in contact with plutonium.
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The beryllium sphere reflected the neutrons emitted by the plutonium, setting off a short nuclear chain reaction. Zlotin held a reflector in his left hand. In his right hand he held a screwdriver, which had to be pushed between two hemispheres. While Zlotin was lowering the beryllium hemisphere, his colleague Roemer Schreiber took a short break from the experiment, believing that the experiment at this stage was unremarkable. At that very moment, Roemer heard a loud sound behind his back - Zlotin's screwdriver slipped off the reflector, and the hemisphere fell entirely onto the core. When Schreiber turned, he saw a flash of blue light and felt a wave of warmth on his face. A week later, he wrote an incident report:
“Despite the fact that the room was well lit, the flash of blue light was clearly visible … The duration of the flash was only a few tenths of a second. Zlotin reacted very quickly and threw the reflector off the core. The time was around three o'clock in the afternoon"
The soldier guarding the precious plutonium was also in the room at the time of the experiment, but did not have the slightest idea about its essence. However, when the core began to glow and the scientists began to scream loudly, he abruptly ran out of the laboratory and climbed the nearest hill. In the course of subsequent calculations, it turned out that the decay reaction was about three septillions - a million times less than in the case of the first atomic bomb, but this was enough to release a large amount of radiation. This radiation excited electrons in the air, which, as the excitation faded, emitted high-energy photons, which caused the blue light.
An ambulance was called and almost the entire laboratory was evacuated. Scientists who were waiting for help tried to figure out how much radiation they managed to pick up. Zlotin made a sketch, depicting the position of each person in the laboratory at the time of the release. He then measured the radiation levels on objects near the nucleus - a brush, a Coca-Cola bottle, a hammer, and a measuring tape.
However, this turned out to be a difficult task - the device itself was rather "dirty", since it, like all other objects in the room, was also exposed to radiation. Zlotin instructed one of his colleagues to measure the radioactive background with a film dosimeter - this required getting very close to the still hot core.
The dosimeters also did not provide any useful information, and the very attempt to use them in the report was considered as proof that people, being exposed to this level of radiation, "are not able to make rational decisions."
People who watched the experiment were sent to Los Alamos Hospital. Zlotina vomited once before the examination and several more times during it, and several more times in the next two hours, but the next morning the vomiting stopped. His general condition was satisfactory. However, his left hand, which at first was just numb and tingling slightly, became more and more painful.
At the time of the experiment, Zlotin's left hand was closest to the nucleus, and scientists subsequently determined that this hand accounted for more than 50,000 rem of low-energy X-rays. The total dose that Zlotin received was 21 hundred rem of neutron, gamma and X-ray radiation (five hundred rem is considered a lethal dose for humans).
The hand eventually took on a waxy, cyanotic appearance and blistered. Doctors watching Zlotin kept his hand in an ice bucket to relieve pain and inflammation. His right hand, holding the screwdriver, had the same symptoms but was less affected.
Zlotin called his parents in Winnipeg and the army paid for their flight to New Mexico. They arrived four days after the accident. On the fifth day, Zlotin's white blood cell count dropped significantly. His temperature and pulse fluctuated constantly.
“On the fifth day, the patient's condition began to deteriorate rapidly,” the medical report said. Zlotin suffered from nausea and abdominal pain, and he also began to lose weight a lot. He suffered from internal radiation burns - one of the doctors called this situation "three-dimensional sunburn." On the seventh day, Zlotin experienced bouts of "confusion". His lips turned blue and he was placed in an oxygen tent.
In the end, Zlotin fell into a coma. He died on the ninth day after the incident, at the age of 35. The cause of death was recorded as "acute radioactive syndrome." His body was transported to Winnipeg, where he was buried - in a closed army coffin.
Zlotin was only one of two people who died from radiation in the Los Alamos laboratory while it was under the control of the army. From 1943 to 1946, there were two dozen other deaths - car accidents, careless handling of weapons, suicide, one drowned man, and another fall from a horse.
Four people died from poisoning with nutmeg wine mixed with antifreeze. Only one Zlotin and his colleague Harry Daglyan fell victim to the dangerous conditions associated with the work on the "Manhattan" project. Nine months before the accident with Zlotyn, Daglyan was working with the same plutonium core, and performing a slightly different experiment, in which tungsten-carbide blocks were used instead of a beryllium hemisphere.
He dropped one of the blocks on plutonium, and the core briefly went critical. Daglyan died from radiation sickness a month after the incident.
After an unsuccessful demonstration by Zlotin, Los Alamos stopped working with subcritical masses of plutonium. Such experiments have always been considered dangerous - Enrico Fermi himself warned Zlotin that he would "die within one year" if he continued his work. However, World War II demanded urgency, albeit at the expense of security.
Hand-collected subcritical masses could be easily and quickly modified and used for military purposes. But by the time Zlotin died, there was no need for such a rush. The times of the Cold War were hectic, but they did not require such sacrifices.
In a note written after the accident, it was suggested that the following experiments should be carried out using a remote control, and "the law of inverse proportionality to the square of the distance should be approached wider" - to the fact that a slight increase in distance significantly reduces the strength of the radiation.
The subcritical plutonium mass that killed Daglyan and Zlotin was initially referred to as "Rufus", but after these two incidents it was given the name "Charge-demon". While the bombs dropped on Hiroshima and Nagasaki, which killed tens of thousands of people, did not receive such attention and remained unnamed.
This, perhaps, is the difference between intentional and unintentional harm, between the nucleus of an atomic bomb, a weapon of mass destruction, and a nucleus reserved for the field of experiments.
Prior to the incident, Los Alamos had planned to send the core to Bikini Atoll in the Marshall Islands, and detonate it in front of more than a thousand observers (at a safe distance) as part of Operation Crossroads, the first post-war series of atomic bomb tests. (Zlotin also wanted to go there and observe the explosion; he planned to teach at the University of Chicago when the test cycle came to an end.)
After the incident, however, the core was still too hot and radioactive for use. They were going to blow it up in the third test of "Crossroads", but the test was canceled. As a result, the core still came to an end, but in a much more prosaic form - in the summer of 1946 it was melted down and cast into a new bomb.