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Summary
The geometry of the Cherenkov radiation. In the figure, v is the velocity of the particle (red arrow), β is v/c, n is the refractive index of the medium. The blue arrows shows the direction of the radiation. So:
Made by Arpad Horvath (previous versions en:Image:Cherenkov.png and hu:Image:Cserenkov.png)
Cherenkov radiation glowing in the core of a TRIGA reactor Cherenkov radiation (also spelled Cerenkov or sometimes Äerenkov) is electromagnetic radiation emitted when a charged particle passes through an insulator at a speed greater than the speed of light in the medium. ...