Status of the PMT development for KM3NeT

KM3NeT is a future large volume (multi km3) neutrino telescope to be constructed at the bottom of the Mediterranean Sea. The detection volume will be instrumented using multi-PMT optical modules, consisting of an array of small photomultipliers housed in a spheric glass vessel. Three companies are presently developing 3-in. PMTs as candidates for the construction of these modules. Main characteristics of the prototypes, such as quantum efficiency, single electron gain, dark current and transit time spread, are required to meet the specification established by the KM3NeT consortium. ort on the current stage of PMT development and recent results of tests performed at the Erlangen Centre for Astroparticle Physics.