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SuperK Neutrino Detector Severely Damaged.
Eric Sharkey writes "The Super-Kamiokande neutrino detector, which announced the discovery of neutrino oscillation and mass in 1998 (covered by Slashdot at the time), has been severely damaged. The NY Times (free reg, blah blah) has an article here. Most of the phototubes have been destroyed. Repair estimates top $30M, leaving the world far less capable of observing the next supernova neutrino burst, should it arrive before repairs or a replacement could be completed." CD: I called the lead of the project and he was in the tank checking out the damage. The webpage for the Super-Kamiokande is here. There are pictures for you to peruse.
While the accident is a tragic blow to some valid and interesting research, no one should lose any sleep over the possibility of being unable to analyze the next big supernova before it can be repaired. After all, supernovae on the scale of SN1987A occur once every few hundred years (the last two occurred in 1054 and 1572.) I suspect repairing Super-K will take significantly faster than that.
Even in the minuscule chance that a big supernova will occur in the meantime, Super-K isn't the only neutrino observatory around. The Sudsbury Neutrino Observatory, a similar experiment, is online and producing some very good results.
One of my colleagues used to work at Fermi Lab and he mentioned once that the light sensors that were damaged are extremely sensitive to saline solutions (such as water that has any appreciable amount of non-neutral-pH molecules). His speculation was that the deionized water that they were using had developed impurities in it, possibly from rusting pipes or failed filters, and those impurities set off the chain reaction in question.
Naturally this is all speculation, but it sounded plausible to me. Does anyone with a stronger chemistry background than mine know if this is a likely cause?
-sting3r
...have no charge and no mass...
No charge - correct. However, as the article mentions, recent experiments indicate that neutrinos have some mass. They also have spin 1/2, like electrons.
are very fast
This is related to mass. If they had zero mass, they would travel at the speed of light (like photons, which have no rest mass). However, if they do have mass, then they have to travel at slightly less than the speed of light.
Supernova observations can be used to estimate neutrino mass, by measuring the time difference between the arrival of visible light from the supernova, and the arrival of a neutrino pulse. Over those vast distances, even a very small difference in speed could lead to a significant difference in arrival times.
and pass through the planet so fast most detection has to be done underground...
This is a bit off. The interesting item is that most neutrinos pass right through the planet without interacting with any atoms. Because they interact so weakly with matter, a detector will only see a very small number of events caused by neutrinos, even though there are bazillions of neutrinos passing through it every second.
However, a detector on the surface of the earth would also see events not from neutrinos, but from other cosmic radiation like muons (actually, muons generated in the upper atmosphere by cosmic radiation). Going deep underground blocks out all particles except neutrinos, enabling the experimenters to get accurate measurements.