Item CERN-OBJ-CE-019 - 20-inch Photomultiplier Tube

Object

The 20-inch photomultiplier tube was first produced by Professor Masatoshi Koshiba in tandem with Hamamatsu Photonics 1979 at the Toyooka Factory in Japan. They were originally developed for a 3000-ton water filled Cherenkov particle detector, Kamiokande-II. This detector was comprised of 1071 PMTs which collected photons induced in the water by particles falling on it. In 1987, the Kamiokande-II experiment detected a neutrino burst in the Supernova SN1987A, the first supernova that modern astronomers were able to study in great detail. Prof. Koshiba was awarded a share of the 2002 Nobel Prize for this discovery. Koshiba spent time at CERN in the 1970s before the development of the 20-inch PMT.