The Baikal underwater neutrino telescope: Design, performance and first results

Abstract A first deep underwater detector for muons and neutrinos, NT-200 , is currently under construction in Lake Baikal. Part of the detector, NT-36 , with 36 photomultiplier tubes at three strings, has been installed in 1993. This array allowed for the first time a three-dimensional mapping of Cherenkov light deep underwater. Since then, various arrays have been almost continuously taking data. Presently a 96-PMT array is operating. We describe the NT-200 detector design and present results obtained with NT-36 .