NEUTRINO research has suffered a major setback. Japan鈥檚 Super-Kamiokande
detector is out of action after one of the phototubes lining its water-filled
tank imploded during a routine refill. The shock wave destroyed another 7000 of
11,000 vacuum tubes, which pick up flashes of light created when neutrinos
interact with the water. The tank is now contaminated with glass and
chemicals.
The main loss is an experiment called K2K in which neutrinos were fired from
Tokyo to the Super-Kamiokande to measure how rapidly they change from one type
to another. Yoji Totsuka, the experiment鈥檚 director, says the detector will be
rebuilt and the experiment resumed as quickly as possible. Repairs could take a
year.