The SOCIB Oceanographic Research Vessel participates in the LSC campaign to test light sensors of the Hyper-Kamiokande international neutrino telescope

• This is a collaboration between two Unique Science and Technology Infrastructures (ICTS, in its Spanish acronym) to develop cutting-edge research.

Light sensors of the Hyper-Kamiokande international neutrino telescope on board the Research Vessel R/V SOCIB.

Between February 13 and 17, the Balearic Islands Coastal Observing and Forecasting System (ICTS SOCIB) has made the Research Vessel R/V SOCIB available to the Laboratorio Subterráneo de Canfranc (ICTS LSC). This collaboration between both Unique Science and Technology Infrastructures (ICTS) has made it possible to validate the resistance to underwater implosion of the light sensors of the Hyper-Kamiokande international neutrino telescope, in the bay of Palma, Mallorca. The tests have been carried out at a depth of 70 meters, involving the work of the engineering and physical staff of LSC, the University of Girona (UdG), the International Center for Physics of Donostia (DIPC), and the Institute for Cosmic Ray Research (ICRR) of the University of Tokyo; as well as the technical staff of the ICTS SOCIB.

This campaign is part of the international scientific project for the construction of the Hyper-Kamiokande (HKK) neutrino telescope, involving Spanish participation. The objective of the project, which will begin to operate in 2027 in Kamioka (Japan), is to demonstrate the theory associated with an essential property of neutrinos that would explain the imbalance between the production of matter and antimatter at the beginning of the Universe. According to those responsible, this project will lead, for the next two decades, the exploration of the thermonuclear processes that give rise to the Sun's energy and that of the processes prior to the collapse of stars that generate supernovae. The HKK detector will have eight times the mass of its predecessor, the Super-Kamiokande detector, and will consist of a 71-meter-high, 68-meter-diameter cylinder of ultrapure water, equipped with newly developed high-sensitivity photosensors.

As part of the project, LSC is working on the production of 20″ photomultiplier tubes (PMTs) covers and on the design of ventilation and geomagnetic systems and electronic components, including light sensors. In particular, during the campaign on board the R/V SOCIB, “tests have been carried out to verify the feasibility of security systems that prevent the implosion of a neutrino telescope light sensor from affecting other sensors, destroying them”, explains the director of the ICTS LSC, Carlos Peña. It is “a ‘frontier’ experiment from which satisfactory results must be obtained in order to continue with the project”, he adds. Furthermore, “the structures designed and created ad-hoc in this regard are 100% Spanish-made. So that in case of success in the tests, the Spanish industry would benefit”.

The participation of the R/V SOCIB in this experiment is part of the competitive access to the ICTS SOCIB, which encourages the use of its facilities and services by public research groups and the private sector, both from the national and international community, through a competitive open access process. As explained by the director of SOCIB, Joaquín Tintoré, “ICTS, like SOCIB and LSC, have three fundamental characteristics: they are publicly owned infrastructures, they are unique, and they are open to competitive access. In this sense, at SOCIB we are committed to offering a quality public service in a strategic alliance with other ICTS”.

During the campaign, the secretary general for Research of the Ministry of Science and Innovation, Raquel Yotti, accompanied by the deputy director general and deputy deputy director general for Large Scientific and Technical Facilities, José Ignacio Doncel Morales and Ángela Fernández Curto, the vice president of Scientific and Technical Research of the CSIC, José María Martell, the councilor of European Funds, University and Culture of the Balearic Islands Government, Miquel Company, the general director of University Policy and Research, Pep Lluis Pons, the head of the Research and Development service, Catalina Maria Canals Gili, and the director of the ICTS SOCIB, Joaquín Tintoré, have visited the B/O SOCIB to see first-hand the objectives and progress of the project.

Authorities on board the Research Vessel R/V SOCIB.

About the Spanish contribution to the HKK project

The Spanish Hyper-Kamiokande Consortium is made up of the Center for Astroparticles and High Energy Physics (CAPA) of the University of Zaragoza, the International Center for Physics of Donostia (DIPC), the Institute of High Energy Physics (IFAE), the Laboratorio Subterráneo de Canfranc (LSC), the Autonomous University of Madrid (UAM), the University of Girona (UdG), the University of Oviedo (UO), the Polytechnic University of Valencia (UPV), and the University of Santiago de Compostela (USC). These nine institutions contribute through the development, production, and installation of the photosensor protection covers, the ventilation system, the geomagnetic compensation system, electronic circuit modules, radiation sources for calibration, and different elements of the nearby detector.

A part of the Spanish contribution to the HKK project is financed with funds from the Recovery, Transformation, and Resilience Plan (PRTR), as one of the actions of the line of strengthening the capacities, infrastructures, and equipment of the agents of the Spanish System of Science, Technology, and Innovation through the promotion of new actions in large European and international research infrastructures.