Part 3
Projects & Landmarks
Physical Sciences & Engineering / Project

KM3NeT 2.0

KM3 Neutrino Telescope 2.0

A network of neutrino telescopes in the Mediterranean Sea for astroparticle and oscillations research


The KM3 Neutrino Telescope 2.0 (KM3NeT 2.0) is a three-sites Research Infrastructure housing the next generation neutrino telescopes. Once completed, the telescopes will have detector volumes between megaton and several cubic kilometres of clear sea water. Located in the deepest seas of the Mediterranean, KM3NeT 2.0 will open a new window on our Universe, but also contribute to the research of the properties of the elusive neutrino particles. With the ARCA telescope, KM3NeT 2.0 scientists will search for neutrinos from distant astrophysical sources such as supernovae, gamma-ray bursters or colliding stars. The ORCA telescope is the instrument for KM3NeT 2.0 scientists studying neutrino properties exploiting neutrinos generated in the Earth’s atmosphere. Arrays of thousands of optical sensors will detect the faint light in the deep sea from charged particles originating from collisions of the neutrinos and the Earth. The facility will also house instrumentation for Earth and Sea sciences for long-term and on-line monitoring of the deep sea environment and the sea bottom at depth of several kilometers.

In the ESFRI Roadmap since 2016, KM3NeT 2.0 is in the Implementation Phase and will start delivering science in 2020.


The discovery of a flux of very energetic cosmic neutrinos reported by IceCube represents de facto the birth of the neutrino astronomy. Many questions arose about the origin of the observed cosmic neutrinos – do they come from sources in our galaxy or do they have an extragalactic origin, can these sources be localised and are they point-like or not? Other questions concern the energy spectrum and the flavour composition of the flux. As a consequence of this discovery, the importance of building a cubic kilometre (KM3) scale high-energy neutrino telescope in the northern hemisphere became even more strong and led to the definition of the next phase in construction of the KM3NeT 2.0 infrastructure with the ARCA telescope dedicated to the search for very high-energy cosmic neutrinos. Thanks to its location in the Mediterranean Sea, the ARCA telescope provides a coverage of 87% of the neutrino sky and allows a survey of almost the whole galaxy including the Galactic Center.

Another goal of the KM3NeT 2.0 scientists is to study the properties of the neutrino particles themselves. The sizable contribution of electron neutrino to the third neutrino mass eigenstate as reported by Daya Bay, Reno and other experiments paved the way for the determination of the neutrino mass hierarchy that is one of the last neutrino properties to be measured. The design of the ORCA detector of KM3NeT 2.0 is optimised for the study of neutrinos created by cosmic rays in the Earth’s atmosphere. Together, the ARCA neutrino telescope and the ORCA neutrino detector of the KM3NeT 2.0 Research Infrastructure offer the scientists the unique possibility of performing both all flavour neutrino astroparticle physics and also to advance fundamental neutrino particle physics.

KM3NeT 2.0 addresses neighbouring disciplines like astrophysics (sources of cosmic rays, high-energy neutrino astronomy), particle physics (neutrino oscillations, search for exotic particles) and cosmology (dark matter), but has also strong connections to Earth and Sea Sciences. To measure deep-water parameters with cabled sensors will add a novel option to the toolbox of oceanographers and marine biologists.

steps for implementation

Three suitable deep-sea sites are identified, namely going from west to east, KM3NeT-Fr, off-shore Toulon (France), KM3NeT-It, off-shore Portopalo di Capo Passero (Italy) and KM3NeT-Gr, off-shore Pylos (Greece). The first phase of construction of the KM3NeT 2.0 Research Infrastructure has begun in 2015 at the KM3NeT-It and KM3NeT-Fr site and is expected to be finished in 2017. For this, a Memorandum of Understanding for KM3NeT-phase1 has been sign by all participating funding agencies. For the next phase of construction, a Letter of Intent for KM3NeT 2.0 has been published. This Letter of Intent will serve as a reference document for requests for funding by the various stakeholders in Europe and abroad. Pending funding, KM3NeT 2.0 could become reality as early as in 2020. The third and final phase of construction of the KM3NeT Research Infrastructure will also include the KM3NeT-Gr site and is foreseen to start after 2020.

legal status
political support
lead country
prospective member countries
The full list of research institutions involved must be found in the website of the RI
Roadmap Entry
Preparation Phase
Implementation/Construction Phase
Operation Start
estimated costs
capital value
196 M€
Not Available
45 M€
151 M€
3 M€/year

KM3NeT-HQ Amsterdam Science Park
Amsterdam, The Netherlands