Cherenkov radiation

<p>Cherenkov radiation  is <a href="/facts/Electromagnetic_radiation/Ynx7ujCW">electromagnetic radiation</a> emitted when a <a href="/facts/Charged_particle/2zqBJGse">charged particle</a> (such as an <a href="/facts/Electron/L0KBo5cW">electron</a>) passes through a <a href="/facts/Dielectric/PnVt9P2G">dielectric</a> medium (such as <a href="/facts/Distilled_water/AkXShA73">distilled water</a>) at a speed greater than the <a href="/facts/Phase_velocity/m43q3X33">phase velocity</a> (speed of <a href="/facts/Wave_propagation/PXhWIt7k">propagation</a> of a <a href="/facts/Wavefront/5XVoVtDQ">wavefront</a> in a medium) of <a href="/facts/Speed_of_light/sKSQwdNx">light</a> in that medium.  A classic example of Cherenkov radiation is the characteristic blue glow of an underwater <a href="/facts/Nuclear_reactor/8xqjIbge">nuclear reactor</a>. Its cause is similar to the cause of a <a href="/facts/Sonic_boom/Hfnr1Vlz">sonic boom</a>, the sharp sound heard when faster-than-sound movement occurs. The phenomenon is named after Soviet physicist <a href="/facts/Pavel_Cherenkov/q7bCFUTU">Pavel Cherenkov</a>.
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Cherenkov radiation open-in-new

Cherenkov radiation