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Is there a static substance that reflects loose neutrons? I thought that the choices for a substance were either to let the neutron pass through, or to absorb t
by Abekkus 9y ago
Is there a static substance that reflects loose neutrons? I thought that the choices for a substance were either to let the neutron pass through, or to absorb the neutron
- dasmoth 9y agoYes [1]. Beryllium is, I believe, the material of choice (although comes with its own problems, e.g. stupidly toxic dust) [1] https://en.m.wikipedia.org/wiki/Neutron_reflector https://en.m.wikipedia.org/wiki/Neutron_reflector
- userbinator 9y agoIf you're already working with plutonium, whose dust is also very, very toxic (in addition to being radioactive), the additional danger of beryllium doesn't seem so great in comparison.
- cjsuk 9y agoI routinely handled beryllium for a couple of years as it is present in certain electronic RF power amplifiers. It’s perfectly safe in solid form. If you drill it or smash it, a different matter! Plutonium, not so much.
- eloff 9y agoI knew a software engineer who made a lot of money in a startup and bought himself an ultralight bike of titanium and beryllium. They ceased the beryllium parts at the Canadian border and I don't think he ever managed to get them released to him.
- badmin_ 9y agoBeryllium's also used as a neutron multiplier.
- madengr 9y agoI think only about 2% of the population is sensitive to beryllium. I was in a beryllium monitoring program (yearly blood tests) at work. A few coworkers are sensitive, one getting really sick.
- rleigh 9y agoBeryllium, amongst others.
- valuearb 9y agogoogle “demon core” for los alamos beryllium reflector hijinks gone awry.
- soVeryTired 9y agoI remember reading somewhere that water slows neutrons down enough to allow for a much lower critical mass. I think it's in mentioned in Richard Feynman's account of his time in Loa Alamos in 'Surely you're joking Mr Feynman'.
- wereHamster 9y agoNot just any water, only https://en.wikipedia.org/wiki/Heavy_water https://en.wikipedia.org/wiki/Heavy_water has that property.
- philipkglass 9y agoHeavy water is more effective, but light (ordinary) water moderates neutrons too. That's how light water reactors work: https://en.wikipedia.org/wiki/Light-water_reactor https://en.wikipedia.org/wiki/Light-water_reactor
- rzzzt 9y agoModerators reflect and slow down neutrons so you get a controlled reaction: https://en.wikipedia.org/wiki/Neutron_moderator https://en.wikipedia.org/wiki/Neutron_moderator