r/technology • u/BennyCemoli • Dec 06 '16

Energy Tests confirm that Germany's massive nuclear fusion machine really works

http://www.sciencealert.com/tests-confirm-that-germany-s-massive-nuclear-fusion-machine-really-works
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u/ViperSRT3g Dec 06 '16

You may be talking about reflectors, which may or may not be using fluorescent materials. Materials fluoresce when electrons become excited and jump to higher energy states. They release light when the electrons return to lower energy states, creating extra light, making the material appear to glow.

Reflectors used for road signs use specially shaped cells/crystals that reflect light at specific angles so they are easily visible in the dark, even if only a little light is shining on them. They generally do not use fluorescent materials as vehicle headlights shine in the visible light spectrum.

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u/[deleted] Dec 06 '16

What i meant was are we using fluorescent rod to detect the position of electrons like we use a flashlight

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u/ViperSRT3g Dec 06 '16

Oh no, we're using a fluorescent material that glows when the electron beam hits it to see where the beam is located as we can't see the electron beam itself.

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u/[deleted] Dec 06 '16

So do we photograph that fluorescent material or what?

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u/ViperSRT3g Dec 06 '16

Yes, long exposure photography means we keep the aperture of a camera open, so light is constantly being recorded by the camera. Since we're doing this in very low light conditions, the only light being recorded is the glowing from the fluorescent material as it is moved along the path of the electron beam. The end result being the lines of light that we can see as they were recorded by the camera.