I think it's been hypothesized that the eye jello allows for a much lower energy particle to to create the flash. They do know it's possible to induce it, but it's not exactly ethical to test the conditions that created the various criticality accidents to find out.

[–] nialv7@lemmy.world 2 points 11 hours ago* (last edited 8 hours ago) (1 children)

I heard it's also possible that the radiation hit your retina and make your neurons go off? Maybe even your visual cortex?

[–] peoplebeproblems@midwest.social 2 points 8 hours ago* (last edited 8 hours ago)

Again, it's not easy or ethical to test, but any charged particle interaction with a nerve for instance will possibly trigger an action potential, inducing the "light" that is witnessed. However, this is unlikely given that the optic nerves are pretty well protected.

What is more likely to occur is that a sufficient amount of gamma rays or x-rays ionizing the nerve or nerve sheathe itself and those unstable particles decay into something that releases a charged particle triggering the nerve signal.

[–] sleep_deprived@lemmy.dbzer0.com 9 points 1 day ago (1 children)

Oh cool! I hadn't considered that. The crystallin and vitreous humor in the eye do indeed have a refractive index similar to water, so Cherenkov radiation happens at less than 1 MeV IIRC, so it comes down to how much light would actually be produced in such a small volume. It does seem perfectly feasible!

[–] Zwiebel@feddit.org 4 points 14 hours ago (1 children)

So we can see radiation afferall

[–] peoplebeproblems@midwest.social 1 points 9 hours ago

Sort of? Radiation refers to any ionizing wave- particle. This means ultraviolet, x-rays and gamma-rays are not possible to see.

Alpha and beta particles can only produce visible light if they are moving faster than the medium that light travels through. Because Alpha and Beta particles are massive they cannot reach c (speed of light in a vacuum) but in water, as being discussed, any velocity >0.75c will produce the light.

Electrons and positrons are a much lower mass and require much lower energy to get moving at a sufficient speed. This means beta decay is a candidate for it, but the beta decay of naturally radioactive elements is too low of an energy for this to be observed. In nuclear fission, the neutrons won't interact this way as they aren't charged. The immediate fission products, however, are usually of very high instability and some of these do decay by beta emission in a very short period of time.

Alpha particles, which are usually 5 mev, do not create the light, as they are much more massive. These are released from things like Uranium-238 to Thorium-234.