KM3NeT

The Cubic Kilometre Neutrino Telescope, or KM3NeT, is a European research infrastructure located at the bottom of the Mediterranean Sea.

[1] Arrays of thousands of optical sensor modules detect the faint Cherenkov light in the deep sea from charged particles originating from collisions of the neutrinos and the water or rock in the vicinity of the detector.

The position and direction of the optical modules and the time of arrival of the light on the photomultipliers inside are recorded with high precision.

The oversight, governance and management of the implementation and operation of KM3NeT is conducted by an international collaboration with more than 68 institutions from 21 countries all over the world being involved.

[2] The main objectives[3] of the KM3NeT Collaboration are: In addition to these primary scientific goals, the telescope is a powerful tool in the search for dark matter in the Universe.

Furthermore, the research infrastructure houses instrumentation for other sciences like marine biology, oceanography and geophysics for long-term and real-time monitoring of the deep-sea environment and the sea bottom at depths of several kilometres.

The infrastructures in France and Italy are designed to consist of almost 200 000 light sensors (photomultiplier tubes, or PMTs) distributed in three so-called building blocks: two for KM3NeT/ARCA and one for KM3NeT/ORCA.

A building block comprises 115 flexible vertical strings - or detection units (DUs) - anchored at the seabed.

Each building block thus constitutes a three-dimensional array of photo sensors that can be used to detect the Cherenkov light produced when relativistic particles emerging from neutrino interactions travel through sea water.

[13] A search for neutrino counterparts was performed with KM3NeT data for the third observing run of the LIGO and Virgo gravitational wave interferometers in 2019-2020.

[16] Furthermore, based on detailed Monte Carlo simulations, prospects of the KM3NeT detectors for ORCA as well as ARCA are presented in for example publications:[17][18].

The muon trajectory was reconstructed from the measured times and positions of the first hits recorded on the photomultiplier tubes in the optical modules.

The support was renewed by the Council of the European Union for the 2019-2026 period, allowing for example to launch the KM3NeT-INFRADEV2 project (2023-2025) for the full implementation of the KM3NeT research infrastructure.

KM3NeT takes part in the EMSO network, by providing long-term access for Earth and Sea sciences research.