The optical module of the KM3NeT neutrino telescope is an innovative multi-faceted large area photodetection module. It contains 31 three-inch photomultiplier tubes in a single 0.44m diameter pressure-resistant glass sphere. The module is a sensory device also comprising calibration instruments and electronics for power, readout and data acquisition. It is capped with a breakout-box with electronics for connection to an electro-optical cable for power and long-distance communication to the onshore control station. The design of the module was qualified for the first time in the deep sea in 2013. Since then, the technology has been further improved to meet requirements of scalability, cost-effectiveness and high reliability. The module features a sub-nanosecond timing accuracy and a dynamic range allowing the measurement of a single photon up to a cascade of thousands of photons, suited for the measurement of the Cherenkov radiation induced in water by secondary particles from interactions of neutrinos with energies in the range of GeV to PeV. A distributed production model has been implemented for the delivery of more than 6000 modules in the coming few years with an average production rate of more than 100 modules per month. In this paper a review is presented of the design of the multi-PMT KM3NeT optical module with a proven effective background suppression and signal recognition and sensitivity to the incoming direction of photons.
French National Research Agency (ANR) ANR-15-CE31-0020 Centre National de la Recherche Scientifique (CNRS)
Commission Europeenne (FEDER fund) Commission Europeenne (Marie Curie Program)
Institut Universitaire de France (IUF)
LabEx UnivEarthS ANR-10-LABX-0023 ANR-18-IDEX-0001
Paris Ile-de-France Region, France
Shota Rustaveli National Science Foundation of Georgia (SRNSFG), Georgia FR-18-1268
German Research Foundation (DFG)
Greek Ministry of Development-GSRT
Istituto Nazionale di Fisica Nucleare (INFN), Ministero dell'Universita e della Ricerca (MIUR), PRIN 2017 program, Italy NAT-NET 2017W4HA7S
Ministry of Higher Education, Scientific Research and Innovation, Morocco
Arab Fund for Economic and Social Development
Nederlandse organisatie voor Wetenschappelk Onderzoek (NWO), the Netherlands
National Science Centre, Poland 2015/18/E/ST2/00758
National Authority for Scientific Research (ANCS), Romania
Ministerio de Ciencia, Innovacion, Investigacion y Universidades (MCIU): Programa Estatal de Generacion de Conocimiento PGC2018-096663-B-C41 PGC2018-096663-A C42 PGC2018-096663-B-C43 PGC2018-096663-B-C44
Center for Forestry Research & Experimentation (CIEF) PROMETEO/2020/019
Generalitat Valenciana: Grisolia program GRISOLIA/2018/119 GRISOLIA/2021/192 Generalitat Valenciana: GenT program CIDEGENT/2018/034 CIDEGENT/2019/043 CIDEGENT/2020/049 CIDEGENT/2021/023
Junta de Andalucia AFQM-053-UGR18
La Caixa Foundation LCF/BQ/IN17/11620019
EU: MSC program, Spain 101025085