Subluminal Cherenkov radiation

[Zefram]

Does anyone have any more information on the following (I haven't looked yet)?

Subluminal Cherenkov radiation. In vacuum, nothing travels faster than light. In transparent substances like water, however, it is possible for high-energy charged particles to exceed the speed of a light beam in that substance. When this happens, the particle will radiate a cone of light called Cherenkov radiation. A team of researchers (University of Michigan and Max Planck Institute for Condensed Matter Research in Stuttgart) has now taken a closer look at the theory, and found that conical Cherenkov emission also occurs at subluminal speeds. The researchers verified the finding experimentally using subpicosecond laser pulses to generate--through a nonlinear optical process--relativistic dipoles that emitted infrared Cherenkov radiation in a zinc selenide crystal. (T. E. Stevens et al., Science 291, 627, 2001.) --pfs

From here (http://www.physicstoday.org/pt/vol-54/iss-3/p9.html)

[Ace-of-Spades]

You seem to have mentioned all there is to
know about it. One important thing is that
only charged particles can release it.

All I can tell you is that they use that cone
of light from Cherenkov Radiation to detect
nuetrinos, which are normally extremely hard
to detect because of their very low mass and
zero charge.

Look up how the Super Kamiokande detector works,
and that should explain quite alot about how
they put this radiation to use.

[Zefram]

Am I misreading that or are they saying that charged particles don't even need to move faster than the speed of light in that medium to emit the radiation? What are relativistic dipoles?

The researchers verified the finding experimentally using subpicosecond laser pulses to generate--through a nonlinear optical process--relativistic dipoles that emitted infrared Cherenkov radiation in a zinc selenide crystal.