The first nucleus of the Km3Net underwater telescope has just been anchored at 3,500 meters deep, 80 kilometers off the coast of Portopalo. The goal of this large research infrastructure is the capture of neutrinos, the most elusive and mysterious particles in the universe. This is an international collaboration project that makes use of the contribution of about sixty research centers and in which Italy participates with the National Institute of Nuclear Physics, whose Catania section manages the National Laboratories of the South, in first line in the birth and development of this fascinating adventure.
The scientific scope of this design projects Sicily into the planetary “great game” of research: Km3Net, in fact, also represents one of the great European infrastructures of the ESFRI roadmap (European strategy forum on research infrastructures) and is already one of the most promising experiments for the identification of neutrinos, but through Idmar (in which Cnr and Ingv also participate) it will allow the acquisition of data in the domains of geology, seismology, oceanology and marine biology. The installation of five new detector strings and a structure to supply electrical power and ensure submarine connections were made possible thanks to the Idmar project, funded by the Region for the enhancement of maritime research infrastructures. The components, protected by a spherical structure, were lowered into the Mediterranean, hooked to the seabed and connected to the ground station, before being deployed in their final configuration: operations that required a week-long marine campaign that “gave a spectacular demonstration – commented Giacomo Cuttone, Infn researcher and scientific director of the Idmar project – of the excellent results achieved by the Km3Net collaboration in the development of suitable solutions for technological companies of this magnitude ». “The Mediterranean, in addition to being an ecosystem to be defended and from which to start again for the social and industrial growth of Sicily, Italy and Europe – observed Simone Biagi, researcher of the National Laboratories of the South of Infn and site manager for Km3Net-Italy – becomes a large research laboratory to study the secrets of the universe ».
The new components installed on the lake of Sicily constitute the first nucleus of the Arca telescope (Astroparticle research with cosmics in the abyss), destined to constitute the Km3Net with the French submarine telescope Orca (Oscillation research with cosmics in the abyss) and together they will constitute a telescope of the volume of one cubic kilometer that will exploit sea water as a “detector” for cosmic neutrinos, produced in the universe by catastrophic events. Since neutrinos are the most difficult particles to capture as they interact very little with matter, large detectors are required to observe them. In its final configuration, the Km3Net telescope provides a network of over 200 detection strings, each 700 meters high and with 18 optical modules equipped with ultra-sensitive light sensors capable of recording, in the deepest darkness of the Mediterranean abysses, the very weak flashes of light generated by the particles produced by the interactions of cosmic neutrinos with water. In total, six detection strings are now in operation, representing the initial core of the telescopes, in addition to the six in the Orca apparatus.
The measurement lines have been integrated in Catania, in the National Laboratories of the South, and in the Genoa and Naples sections of the Infn, while the optical modules come from the integration sites of the program which are also located in Italy, in Catania and Naples, while the basic modules were made in the Infn section of Bologna and the sections of Bari and Rome, with the connected Infn group of Salerno, contributed to the realization of the electronic and mechanical components of the lines.