KM3NeT - Recent News

Latest news items published on the home page.

Major upgrade of ARCA’s seafloor network

22 November 2022 – After 4 years of  activities carried out by the Italian funding agency INFN and Alcatel Submarine Networks, part of Nokia, the new subsea network for KM3NeT ARCA, funded under the Idmar regional project in Italy, is now complete.

The new system comprises a 100 km long electro-optical cable, equipped with 48 optical fibres for detector control and data communication and two electrical conductors for power distribution, connected to the shore station control and power feeding equipment, that can deliver up to 80 kW offshore. The cable is bifurcated in order to serve the two building blocks foreseen in ARCA.

During a 10 days long sea operation, which ended on November 17th, a cable termination frame (CTF) was installed on the northern branch of the cable. To this purpose the end of the cable, which was deployed already in 2020, was recovered from the sea floor and connected to the CTF onboard the deployment ship – the Ile d’Ouessant of Alcatel Submarine Networks. Then the CTF was carefully deployed to the target position on the sea floor. Extensive tests were done before and after the deployment to ensure its nominal behaviour.

The CTF is a large-size, 12-ton component which is equipped with four medium voltage converters and a total of 16 electrical and optical subsea connectors for connecting a set of submarine junction boxes to which the detection units will be in turn connected.

With this installation the connectivity and power transmission capabilities of the network have been increased by a factor four compared to the first part of the network, used to run the set of junction boxes and the first 30 detection units of ARCA Phase 1. This will allow for the completion of the construction of the first building block of ARCA and prepares the field for the installation of a second CTF on the other branch of the cable for the second building block.

The CTF at the end of the integration.
CTF onboard Ile d’Ouessant.
Overboarding of the CTF.

An inspiring collaboration meeting in Rome

31 October 2022 – What a week last week!

A large fraction of the KM3NeT collaboration met in Rome for a vibrant collaboration meeting, in remote connection with those who could not come in person.

The venue was Centro Ricerche Enrico Fermi, at the historical building where Enrico Fermi and his team made surprising discoveries in the ’30s. The site is also well known for a prestigious physics conference which was hosted there in 1931 and represented a milestone for nuclear research for decades. What a source of inspiration that was! It is in fact after a suggestion of Enrico Fermi that the neutrinos, those elusive particles which are the main subject of research of KM3NeT, were named so. He also formulated the first theory of weak interactions including neutrinos.

During the meeting we reviewed the progress in data analysis and in the construction of the ARCA and ORCA detectors. We also refined the plans for two new funding projects which are about to start in France and Italy – NEUMED and KM3NeT4RR – which will allow for significant extention of the two detectors.

The collaboration is growing: new research teams from Technical University of Prague (team leader: Ivan Stekl),  Comenius University of Bratislava (team leader: Fedor Simkovic) and Université Mohammed VI Polytechnique of Ben Guerir in Morocco (team leader: Ahmed Ratnani) were welcomed; and Yuri Y. Kovalev (now at MPIfR, Bonn) applied for joining as an associated member. Almost 30 new colleagues from the various international KM3NeT institutes and our new quality team, comprising quality manager Céline Pariès and quality officer Cédric Vérhilac, made their debut in a collaboration meeting.

Our management team was elected for a second two-year mandate.

With many thanks to our colleagues of La Sapienza University and INFN Rome for an excellent organisation!

 


New sea campaigns at both KM3NeT sites

12 September 2022 – New sea campaigns were performed last week for both ARCA and ORCA. The purpose was to prepare the field for next installation phases of the detectors as well as to deploy new detection units and acoustic beacons – the latter are autonomous calibration devices which run on batteries and need to be replaced after some time.

The number of detection units in operation in the deep sea has been increased to 32 (comprising almost 18,000 photomultipliers): 21 in ARCA and 11 in ORCA.

After installation of a third junction box at the ARCA site, this site is now fully equipped for hosting the so-called Phase-1 of the project, comprising the first 31 detection units and the calibration unit of the apparatus.

The ARCA sea campaign represented the final action of the IDMAR project in Italy, supported by Regione Sicilia.

These operations were made possible by the dedication of hardware teams and the onshore and offshore teams at the two sites – the Collaboration is very grateful to them.

The newly added junction box of ARCA on the sea bottom.
Detection unit deployment at the ORCA site.

KM3NeT at ICHEP 2022

For the first time, the International Conference on High Energy Physics was organized in Italy. This major conference in our field was the opportunity for KM3NeT and ANTARES members to present the latest updates from our experiments.

Some of our collaborators were also involved in the organization of the conference being held in Bologna.

The various talks and posters are available on the website of the conference:

Group picture of some of the KM3NeT members attending ICHEP (showing how seriously they considered this great opportunity!)

Rebecca Gozzini summarizing the potential of ANTARES and KM3NeT for indirect dark matter searches.

Valentin Pestel describing the KM3NeT sensor technology that allows the collaboration to carry out oscillation neutrino studies.

An overview of the recent results of ARCA presented by Piotr Kalczyński.

Victor Carretero presenting his work on the search for new physics in the neutrino sector.

Maurizio Spurio getting ready to present the latest highlights from ANTARES.


Isabel Goos before presenting the potential of KM3NeT for supernova neutrino searches.

Gwenhael W De Wasseige talking about KM3NeT during her plenary talk on multi-messenger physics.


Welcome KM3NeT/ARCA19

14 June 2022 – The sea campaign for enlarging the KM3NeT/ARCA submarine telescope which was started on June 2, has been completed today with a full success. As a result, data taking with ARCA has been resumed with 19 detection units in operation!

This represents a major step forward for the collaboration, as this was the first time that a 2-weeks campaign was performed. The scope of the operation in fact was twofold: to upgrade the submarine network, by installing 2 new junction boxes in replacement of the junction box that we had been operating so far, and to install 11 new detection units (DUs). The operation therefore took place in two steps: after the first round of activities for installation of the junction boxes and the first 4 DUs, the ship went back to shore to pick up the remaining set of 7 DUs.

The campaign was performed with Handin Tide, of the FUGRO company, which had already performed the previous sea campaign for KM3NeT/ARCA last year, sailing off from Malta.

All planned activities were performed with full success, including ancillary operations such as the replacement of one autonomous acoustic beacon on the sea floor. A speed record was also established, with 7 detection units installed, connected and unfurled in less than 48 hours!

As a result of the campaign, the size of ARCA has more than doubled: It now comprises 19 detection units in operation, equipped with more than 10,000 photomultipliers,

The KM3NeT collaboration wishes to thank the Handin Tide crew for their top-level performance, the KM3NeT teams which worked tirelessly offshore and onshore to reach this remarkable success, as well as all teams which work so hard at the almost 30 integration sites of the collaboration to produce the DUs for building the apparatus.

Below is a gallery of pictures from the campaign. A log of the activities while the operation was ongoing is available on our blog.

Detection units in the port of Malta awaiting deployment.
Loading of a detection unit onto Handin Tide.
Handin Tide leaving Malta for the first phase of the campaign.

Deployment of one of the junction boxes installed in the campaign.

The deck of Handin Tide loaded with DUs for the second phase of the campaign.
Connection of one detection unit on the sea bottom.
The onshore control station at Portopalo di Capo Passero during the campaign. More than 30 people from 10 institutes in France, Italy and the Netherlands participated in the activities onshore.

KM3NeT@neutrino2022

Fifty years ago, in 1972, the first neutrino conference was held in Hungary, because the organisers were not satisfied with the subdued position of neutrino interactions at the international conferences at that time. Nowadays, the neutrino conference is one of the major conferences in neutrino (astro)particle physics. Neutrino2022 took place in virtual Seoul, 30 May-4 June, 2022 and of course KM3NeT was there to show the results of data taking with the first detection units of ARCA and ORCA.

Aart Heijboer, physics coordinator of KM3NeT, showed the results of one year of data taking with ORCA6 and 100 days with ARCA6. The ‘6’  refers to the number of detection units in a detector used in the data analysis.

The ORCA detector is optimised to measure the oscillation parameters of neutrinos travelling through the Earth. Neutrino oscillation is a quantum mechanical phenomenon in which a neutrino created with a particular flavour – electron, muon or tau neutrino – can be later measured to have changed its flavour. In figure 1 below, it is evident that the data does NOT follow the flat blue horizontal line indicating the absence of neutrino oscillations. In other words, already with only six detection units, the ORCA6 detector ‘sees’ oscillations. In the second figure two oscillation parameters are plotted against each other. Clearly, the contour of ORCA6 is still wider than that of other experiments. More data with more detection units will make it narrower.

 

Also the ARCA detector, optimised for the search of high energy neutrinos from sources in the Universe, is well underway pushing the limits of the potential to discover sources of neutrinos down towards the expected limits of the full detector.

 

In the poster sessions KM3NeT physicists presented the details of many analyses being performed with the ARCA and ORCA detectors.

Aart Heijboer concluded at the plenary session that ARCA and ORCA will span eight decades in energy, that there is a rich variety of data analyses going on in the collaboration and that construction of the detectors is ramping up. Promising conclusions.

Very nice to have been invited to share the progress of KM3NeT with the community of neutrino (astro)physicists!

The KM3NeT Collaboration thanks the organisers of Neutrino2022 for an excellent edition of the conference. See you in two years time in Milano.