4 ms·

Right, but there's no actual measurement being done, nor it could be done, unless there was some guy there measuring the separation with calipers or something.

Right, but there's no actual measurement being done, nor it could be done, unless there was some guy there measuring the separation with calipers or something. So what's the point, simply to practically demonstrate that less distance = more radiation? I guess that makes some sense, but it seems too trivial of a thing to demonstrate to people in a high level, secret operation. I'm just imagining that for this to actually produce some sort of useful result there needs to be some sort of precise measuring happening. Maybe moving half the sphere with a screw and having a dial indicator there, or something.

ortusdux 3y ago
As I understand it, this was just a demonstration of the technique. The actual experiment called for metal shims between the cores, which I assume were of known thicknesses. Also, from the American Physical Society's writeup: "Nine days after the accident, Slotin died after “a total disintegration of bodily functions.” Ironically, he had become disillusioned with the postwar atomic tests, and one reason for that ill-fated experiment was to train a replacement, so Slotin could resume his prewar research in biophysics and radiobiology at the University of Chicago. He never got that chance. In response to his death, Los Alamos ceased all hands-on experiments with critical assemblies, using remote controlled machines to protect the operators. As for the killer “demon core,” it was used in one of the first postwar atomic bomb tests at Bikini Atoll, a mere five weeks after Slotin’s death. The test went off without a hitch." https://www.aps.org/publications/apsnews/201405/physicshistory.cfm https://www.aps.org/publications/apsnews/201405/physicshisto...
- dale_glass 3y ago
  But what technique? That's what confuses me. If the actual experiment needs precisely sized shims, then any demo should be done with shims. Because you'd want to show people what shims, how they're placed, and what's supposed to happen.

ortusdux 3y ago

As I understand it, this was just a demonstration of the technique. The actual experiment called for metal shims between the cores, which I assume were of known thicknesses. Also, from the American Physical Society's writeup: "Nine days after the accident, Slotin died after “a total disintegration of bodily functions.” Ironically, he had become disillusioned with the postwar atomic tests, and one reason for that ill-fated experiment was to train a replacement, so Slotin could resume his prewar research in biophysics and radiobiology at the University of Chicago. He never got that chance. In response to his death, Los Alamos ceased all hands-on experiments with critical assemblies, using remote controlled machines to protect the operators. As for the killer “demon core,” it was used in one of the first postwar atomic bomb tests at Bikini Atoll, a mere five weeks after Slotin’s death. The test went off without a hitch." https://www.aps.org/publications/apsnews/201405/physicshistory.cfm https://www.aps.org/publications/apsnews/201405/physicshisto...

dale_glass 3y ago
But what technique? That's what confuses me. If the actual experiment needs precisely sized shims, then any demo should be done with shims. Because you'd want to show people what shims, how they're placed, and what's supposed to happen.