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CERN is still CERN. The name has been changed, but what was an acronym has been kept as the short name. And most of all, all of us here at CERN will keep on calling it CERN :-).

Cherenkov radiation is light emitted whenever charged particles pass through matter with a velocity greater than that of the velocity of light in that medium. It's a very very very rough equivalent to a "sonic boom" for light, although I cringe to make that comparison.

So what happens in this case is that fission products, water and other molecules that are ionized by the released gammas (i.e. they've lost electrons or obtained an electrical charge in some way), plus the electrons themselves that get jumping from the increased gamma radiation, go streaking through the water causing more ionization in the surrounding medium. The wavelength of the energy released as these ionized particles just happens to be in the visible range (i.e. blue).

Anyone who's ever seen a research (pool-type) reactor or spent fuel pool has seen this blue glow. Very cool.

Cherenkov Radiation
More Cherenkov Info

Because that speed is very different than the speed of the surrounding area and, since gravity falls off so quickly with distance, (Newton is sufficient here) the fact that the particles in question are moving so quickly is amazing.

Re: No big deal... Havent they goten particals up to 10% the speed of light before in mass accelerators.

I don't know the term mass accelerator, but if you mean particle accelerator then yes, they have gone faster than 10%. Much. The percentage of the speed isn't really important at the level of most detectors but it is more than 99.99%. What is measured is the energy of the accelerator, which for Fermilab is ~2TeV and in the future CERN will run at ~7TeV. See either site for great intros to high energy physics pages.

Preprints KICK ASS!!

Of course, the web was invented by physicsts for JUST THIS PURPOSE. Back in the day at CERN, They wanted a way to share documentation across heterogeneous documentation systems. Tim Berners-Lee (I think that's his name) Came up with a subset of SGML known as HTML and the HTTP, ran a sever and client on a Next box, and Voila! In the begining it was just stuff like schedules, proposals, and budets and the like, but the Pre-prints are only a small leap in imagination.

A wealthy eccentric who marches to the beat of a different drum. But you may call me "Noodle Noggin."

The Siemens cluster is not using 100Mbit Ethernet, it's using SCI (IEEE 1596-1992) at 500Mbyte/s.

With SCI you can use alse use cables (up to 5 meters I beleive) between the different nodes, so you can cluster Linux boxes.

Actually SCI has been used to connect VME craters, check out the RD24 project at CERN (European center for nuclear research).