a few comments
The highlighted comment was created in this revision.
This proposal is fine. I thought there was a miscount in the number of PMTs somewhere in the documents provided. The citation can better indicate what the PMT's are for: support research in proton decay, or elementary particle physics, or spotting supernovas.
The unmber of the PMTs used in the Kamiokande-II detector was 1071 (= 948 + 123) mounted on the cylindrical surface (15.6m radius and 16.1m height) of Cherenkov detector filled with 3000 metric tons of water. Of the 1071 PMTs, 948 units were viewing the inner region of the cylinder, while 123 viewing the outer region surrounding the inner cylinder. (Refer to: FIG. 1, Ref , Hirata et al. and Fig.1, Ref , A. Suzuki et al.) The cosmic particles such as the neutrinos from the supernova hitting the water water in the tank induced photons, which were detected by the PMTs.
Plaque citation revised:
Hamamatsu Photonics K.K. began developing 20-ich diameter photomultiplier tubes at Toyooka Factory in 1979 for a water-filled-Cherenkov elementary particle detector, Kamiokande-II. 1071 PMTs on it collected photons induced in the water by the elementary particles falling on it. Kamiokande-II detected a neutrino burst in the Supernova SN1987A in 1987, opening a window in astrophysics which earned Professor Masatoshi Koshiba a Nobel Prize in 2002.