The quest for the ideal photodetector for the next generation deep-underwater neutrino telescopes

We review photodetectors used in present running neutrino telescopes. After a brief historical discourse, the photodetector requirements for the next generation deep-underwater neutrino telescopes are discussed. It is shown that large-area vacuum hybrid phototubes are the closest to the ideal photodetector for such kinds of applications when compared with other vacuum phototubes. (C) 2008 Elsevier B.V. All rights reserved.