Neutrinos are elementary particles almost massive and interact very little with the subject. For this reason, they are able to cross the universe without being diverted or absorbed, carrying precious information on their cosmic sources.
The neutrino detected by Km3net has an estimated energy of about 220 Pev, a value never observed before. This discovery indicates that in the universe there are processes capable of accelerating extremely high energy particles, such as supermaxicci black holes or supernova explosions.
“The event concerns the revelation of an ultra energy neutrin (Ultra High Energy, UHE) by the neutrinic Revorist Km3net. The uhe neutrinos have energies starting from the petaelectronvolt (pev, 1 pev = 10^15 EV, or one million billions of electronvolt), and this in particular has a record energy equal to at least 100 pev, never measured first for no one Another neutrino. For an elementary particle this energy is a monstrosity, it is in fact more or less equal to the kinetic energy of a tennis ball that rolls on a table “he says Fabrizio Bocchino, researcher of the National Institute of Astrophysicswhich continues: “Uhe neutrinos are of fundamental importance in astrophysics, because they can give us information on some of the most important open problems such as the origin of the cosmic rays and their propagation during the evolution of the universe. In fact, it is believed that Among the most accredited hypotheses on the origin of these neutrinos there is the so -called “cosmogenic”. In particular with the cosmic background radiation (Cosmic microwave background, CMB). , the revelation of even one of these events can give important information on these issues. Where and how these super-energy processes take place, and thus contributing to the study of the other options still open on the origin of the uhe neutrinos and cosmic rays, such as those that concern the supermaxicci black holes and the remains of Supernova“.“
Here is the video that reveals the discovery of the neutrino
“This observation opens the way to multiple interpretations. The very high energy neutrin could come directly from a powerful cosmic accelerator. Alternatively, it could be the first revelation of a cosmogenic neutrino. On the basis of a single event it is difficult to draw conclusions on the origin of the neutrino who produced it, but the extremely high energy places it in a totally unexplored region, of extreme interest in science. Future observations of other events of this type will be used to build a clear interpretative framework”, explains Rosa Rabigione, a researcher of the FN at the National Laboratories of the South and deputy ordinator of the KM3Net collaboration at the time of discovery.
Although neutrinos are the second most abundant particle in the universe after photons, their weak interaction with matter makes them very difficult to reveal and requires large experiments such as Km3net, which uses sea water as a means of interaction for neutrinos. Its high -tech optical modules reveal the Cherenkov light, a bluish glow that is generated during the propagation in the water of the ultra -flowing particles produced in the interactions of neutrinos. The revealed signal It was identified as a single muone that has crossed the entire detector, inducing signs in more than a third of its sensors. The inclination of his trajectory combined with his enormous energy provides a convincing evidence that Muone originated from a cosmic neutrin who interacted near the revealing.
“To determine the direction and energy of this neutrino, a precise calibration of the telescope and sophisticated trace of the track reconstruction was required. In addition, this extraordinary revelation was obtained with only one tenth of the final configuration of the detector, demonstrating the great potential of our experiment for the study of neutrinos and for astronomy with neutrinos”, Comment Aart Heijboer, researcher of Nikhef National Institute for Subatomic Physics, the Netherlands, and Physics and Software Manager of Km3net at the time of revelation.
The neutrinic Revorist Km3net is a European infrastructure under construction which includes two neutrinic detectors partly already positioned on the bottom of the Mediterranean Sea, one off the southern France and the other off the coast of Sicily. These tools do not reveal neutrinos directly, but they manage to observe the effects of the interaction of other elementary particles, the muones, produced by the interaction of neutrinos with the rocky part of our planet below the detectors themselves.
Its revelation units (detection unit, du) 700 m high are anchored to the seabed and positioned about 100 m away from each other. Each du is equipped with 18 digital optical modules (Digital Optical Module, Dom), each containing 31 photomoltiprixers (Photomultiplier). In its final configuration, Arca will include 230 du. The collected data are transmitted via an underwater cable to the land station of the National Laboratories of the South of the FN.
The Km3Net/Orca detector (Oscillation Research with Cosmics in the Abyss) is optimized to study the fundamental properties of neutrinos. It is located at a depth of 2450 m, about 40 km from the Costa di Tolone, France. It will be composed of 115 du, each 200 m high, and spaced by 20 m. The data collected by Orca are sent to the La Seyne Sur Mer Terra di Terra di Terra.
Km3net is an international collaboration between different European and extra-European countries. Italy participates through the National Institute of Nuclear Physics (INFN), while the National Institute of Astrophysics (INAF) participates in the PNRR project linked to KM3NET – called KM3NET4RR – for the part of Scientific exploitation of data, support for multi-member observations and modeling of astrophysical sources of neutrinoswith the coordination of human grace. The KM3Net4RR project is led by the INFN and the Inf research structures involved are those of Palermo and Catania: both participate in the Work Package 7 of the project, the one that concerns the multi-messengera astrophysical issues.
“The exceptional result shows the great potential for the discovery of Km3net and the value of the choices made, both on technological solutions and on the installation site in Sicily, in the heart of the Mediterranean Sea, where it is possible to have a large and only vision of the galactic sky . For the realization of the telescope and for its next completion, the contribution of the European Union is decisive, also with PON Fondi del Mur and POR of the Sicilian Region and the PNRR funds. The Km3net research infrastructure will continue to expand and create new discoveries, bringing Sicily and Italy to the center of the international scientific panorama”, Comment Giacomo Cuttone, National Head of the Infn of the Km3Net project.