The chilling story of the ‘devil’s core’ and the scientists who became its victims

The nuclear bombs on Hiroshima and Nagasaki were the first and only used in a war. However, if Japan had not declared its surrender in World War II on August 15, 1945, a third atomic bomb that US scientists were secretly developing may have further magnified the massacre.

At that time, a team of scientists worked at the Los Alamos National Laboratory (New Mexico, USA) with a 6.2 kg sphere of refined plutonium and gallium. After the surrender of Japan, it was decided that the device should remain in those facilities for further tests with it. However, it was during these tests that that nuclear bomb was nicknamed the ‘demon core’.

As stated in an article published in Science Alert, the first incident with the bomb it took place less a week after the surrender of Japan.

The scientists working on this project were aware of the risks they faced when carrying out a series of tests with this pump. criticality experiments to measure the threshold at which plutonium would become supercritical, the point at which a nuclear chain reaction would lead to a burst of deadly radiation.

The physical Harry daghlian he was the first victim of these experiments. The scientist made the mistake of going to the laboratory and work alone, thus violating security protocols.

The events occurred during the night of August 21, 1945, when Daghlian received a lethal dose of ionizing radiation from the plutonium core. After several weeks of nausea and pain, she finally fell into a coma. He died 25 days after the incident. That day, only one security guard was on the premises, who also received a dose of radiation, but not a lethal one.

The changes made when reviewing safety procedures after this deadly incident were not enough to prevent a similar event the following year.

Canadian physicist Louis Slotin, one of Daghlian’s colleagues, was on May 21, 1946 conducting a criticality experiment similar to the one that ended the life of his colleague. The demonstration consisted of placing two hemispheres of beryllium on the same plutonium core that had killed Daghlian in order to generate a fission reaction.

Slotin made sure the dome never completely covered the core by using a screwdriver with which it maintained a small space that acted as a crucial valve that allowed enough neutrons to escape.

Suddenly the screwdriver slipped and the dome fell, with which the two hemispheres completely covered the nucleus, which reached the supercritical level. This is how the scientist later explained the event Raemer Schreiber, who was present in that room when the incident occurred.

“The blue flash it was clearly visible in the room (…). The total duration of the flash could not have been more than a few tenths of a second. Slotin reacted very quickly by removing the tamper piece, “Schreiber wrote in a report.

Of the eight people who were in the room at the time and were exposed to radiation, only Slotin received a lethal dose. After being hospitalized with nausea and vomiting, he soon began to lose weight and experience abdominal pain and mental confusion. He died nine days after the accident.

From that moment on, the plutonium nucleus was baptized as the ‘demon core’. The two fatal accidents caused plans to be detonated in Operation Crossroads, two US atomic bomb tests on Bikini Atoll in the summer of 1946, to be shelved. Instead, plutonium it melts and it was reintegrated into the US nuclear arsenal to be recast in other nuclei as necessary.