What is Cherenkov Light?

Physicist Janet Conrad explains the phenomena of Cherenkov light, the eerie blue glow often associated with nuclear reactors. Cherenkov light is emitted when charged particles travelling through a medium move faster than light-which has been slowed by the same medium. It is similar to the sonic boom that follows an aircraft that is moving faster than the speed of sound. Scientists can use Cherenkov light to detect neutrinos moving through giant tanks of water.
Watch the full program here: • The Elusive Neutrino a...
Original program Date: June 1, 2012
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[@bbrodriguez420]

Cherenkov blue should be a name for a colour if it isn't already.

[@drsjamesserra]

Love it!

[@PureColumbianCocainum1949]

i love that idea. it actually sounds good saying ''cherenkov blue''

[@TreebeardsHome]

Janet did a wonderful job of explaining this clearly & succinctly. Thank you.

[@FirstNameLastName-okayyoutube]

Come on. I've heard ghost explained better

[@FirstNameLastName-okayyoutube]

Her explanation was entirely that because of refraction which makes light traversing medium slower it therefore goes faster than the speed of light. If that makes sense to you then I have a Democrat candidate that you should vote for.

[@mateusgabriel3013]

Right? Great explanation.

[@donnellyb4616]

@@FirstNameLastName-okayyoutube what does american polotivs have to do ith this

[@BlazinNSoul]

So the color of death is in fact blue lol. So pretty though kinda of hypnotizing isn't it. :/

[@drredstone7198]

BlazinNSoul my fav color

[@Gabriel87100]

The video feels like it was cut before she could finish her explanation

[@Maltebyte2]

Very informative thank you!

[@MervynPartin]

It was always interesting for visitors to see this with newly discharged fuel in the cooling ponds (with the overhead lighting turned off)

[@solarty9500]

such an explanation 🔥🔥🔥❤️❤️❤️❤️❤️

[@bendixtrinity]

well. that does it.

[@roboticjanitor3332]

"Photonic Boom" is such a cool term

[@phuketadvertising]

Bouncing effect same as the supersonic (you ear a boom because the molecule being bouncing at a very high speed same for that blue shiny light +/-) but it is not going faster than the speed of light velocity when coming near the speed of light coming infinite even an electron or a neutrino that is smaller (anything that as a mass nothing) when you are near the speed of light 9X.X of the mass coming infinite put that in your head this bouncing effect that is why you have that shiny blue it is in anyway going faster than the speed of light in not a million year.

[@ChumpyChicken2]

So does it mean if the nuclear fuel is removed from the water for a few seconds, it wouldn’t glow blue?

[@gantmj]

I've read many accounts of those in research mishaps or from those who unknowingly handled nuclear waste that it glows blue in air as well. Look up the story of the "demon core".

[@ronaldderooij1774]

So, what is travelling faster than the speed of light? A medium slows light down and yet it goes faster and produces a light variation of the "sonic boom" that emits photons called Cherenkov light. I don't get it. It contradicts itself. Either light slows down in a medium, or it does not. I am at a loss here.

[@TheIzugec]

+Ronald de Rooij So, for example in a water where index of refraction is 1.33, speed of light will be c/1.33 which leaves possibility for electron to travel faster than the speed of light. So when CHARGED PARTICLE travels faster than the speed of light, phenomena observed is called cherenkov radiation. Why charged particles? Well charged particles means electric field, and what we really mean is cherenkov radiation happens when velocity of charged particle moving is bigger than velocity of electric field which is going at the speed of light. Hope that helps.

[@AndrewBlechinger]

When a photon enters a medium with a higher index of refraction, it gives up some of its energy in order to travel at the speed of light in the new medium. That energy is what we see as Cherenkov radiation.

[@yun-z]

the light just bounce around so it appears slower, and now the source of the light is faster than the apparent speed, nothing is broken here

[@SyncMotion27]

Well I think this woman is talking shit. Radiation travels trough human eye liquid and slows down so it seems like a blue light only for those who are exposed to it. Others, who are far away, can't see blue flash even from a distance.

[@navytiger2]

explained dumb enough for all of us. thank goodness and also that is cool

[@dorrellk7471]

Because Science

[@FirstNameLastName-okayyoutube]

Refraction means that it can go faster than the speed of light in a material... just like reading left to right I watch a videos from the beginning to the end so that's what I had to go off of before example time

[@user-mh2bw4hu3o]

Blue godzilla atomic breath

[@DMan1954]

That's the reason I'm here

[@hikerwithiker55]

i guess i have to know more

[@neoh524]

Light slows as it passes through matter, then speeds back up? Conservation of Energy? Scalar Wave in the Ether

[@johnnyrocketfingers4926]

No one ever said the light speeds back up, the light is absorbed into the medium.

[@danielandrescubidesrodrigu8863]

288 Anatoly Dyatlov counts liked this vid

[@Noruzenchi86]

So assuming the speed of light is slower in a dense medium like water, does that mean that our relative speed of light in space is actually in a medium? Since space isn't a "true" vacuum. Lightspeed could essentially be infinite then, or heavily increased if we were to somehow swim through space like air or water :V

[@Mi_Fa_Volare]

Isn't that just light from ionization?

[@MrSingularity44]

That is what happens when excessive amounts of radiation hits the air. It is a different phenomenom that happens to produce the same color.

[@luthermcgee432]

If light travels at 186,283.4 miles per second in a vacuum, how can light travel faster than said velocity in a medium? A vacuum has no gas, no liquid, no medium to slow it down. So, with a medium present it can be slowed down. So, I don't believe in light velocity exceeding 186, 283.4 mps. There may be souh a thing as an Einstein rosenbridge,( wormhole) which are theoretical physics oriented, but I still believe Albert Einstein's formula E=MC squared.

[@qvindicator]

The speed of light in a medium like water is different than the speed of light in a vacuum. It’s a lot slower in water. This is what is being discussed and particles can go faster than the speed of light in water

[@Ratciclefan]

So that's how it works

[@nick.c6969]

Tastes like blue...

[@IyadQumseya]

Thanks! is it a coincidence that whenever I am trying to solve an issue I find the answer here?! at the same date I was thinking about it???

[@burtgummer463]

Iyad Qumseya I have seen things like that before. Savant?

[@janantoni3]

dabeee di dabeee da

[@farqfarq2225]

Who is the chunky bird.

[@Ojas_Singh]

Top things a human should never see:

[@hapwn]

When science explains away and cover up DEW with a bunch of jargon mumbo jumbo bs! 😃👌

[@izachikun]

And again, every explanation out there doesn't tell where the 'some kind of the charged particle' came from. Next time u should just say 'I don't know where it came from' please....

[@stewiesaidthat]

Nuclear reactors create high frequency EM waves in the Gamma, X-Ray and UV wavelength ranges. Going through water and glass, the EM wave loses energy and the wavelength is stretched out to the visible light spectrum.

[@bernhardhorlezeder5895]

ground zero new york!!!!! NYC!!!