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I've been studying about radiation, and I saw something called the Demon Core. Apparently, it was a core that was under experimentation by the government in Los Alamos to see the exact point at which a mass of plutonium would go critical. It was composed of two hemispheres of beryllium partially enclosing a mass of plutonium and made to reflect the radiation back to the center. But the top dome slipped and shut off the opening and the whole structure briefly went critical. During this brief time, the surrounding are turned blue because the air was being ionized. I'd like to know if this effect can be recorded, or if perhaps the radiation would corrupt the recording system(s) at work. If anyone can give me an explanation, I would greatly appreciate it.

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If the air is emitting visible light, certainly a camera far enough away to be safe from the radiation - or shielded - would be able to record it. –  Nathan Reed Mar 13 '13 at 4:23

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Any delicate equipment, including cameras, should be safe behind a thick wall of lead or other heavy shield. What, it can't see through the shield? Then point the camera sideways, and use a mirror to see around the edge of the shield. Light reflects, like you'd expect. Most of the obnoxious high energy radiation will pass through the mirror, or perhaps melt it - so take your photos quickly. enter image description here

For a scary real life example, try googling "Elephant's foot" and "Chernobyl". I hope this link stays good for a long time: News post with image and brief explanation (if anyone has time to track info to original sources, feel free to update this.) The post states "The original wheeled camera they sent up to take pictures was destroyed by the radiation. This picture was taken using a mirror set around the corner of the hallway within view of this deadly masterpiece."

I suspect NIF (National Ignition Facility) at Lawrence Livermore in California uses imaging sensors for some of the control and data acquisition systems, but perhaps not in the actual fusion chamber. Once that gets going, it will probably be more hazardous to cameras than drab old fission.

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The flash of blue light was probably due to ionisation of the air by the ionising radiation emitted as the experiment went briefly critical. It's no different from the blue light emitted from air in a lightening strike or the Aurora Borealis, so it can be photographed in the same way. Note that it is different from Cerenkov radiation, which is normally caused by high speed electrons. Although nuclear cores emit electrons fast enough to cause Cenerkov radiation in water they do not emit electrons with enough energy to cause it in air.

The Wikipedia article on the Demon Core mentions that several scientists standing some distance from the experiment survived, so I imagine a video camera at this distance (with a telephoto lens) would survive as well.

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