The Extreme Energy Events (EEE) Project combines research and scientific dissemination, representing a unique example in the world. Through a network of 59 Multi-Gap Resistive Plate Chambers telescopes, distributed throughout the national territory inside high schools and research institutes, it offers the possibility to study the flux of secondary cosmic rays and to detect, over a region of hundreds of km, the possible appearance of extended events. About a thousand students per year are involved in all stages of the process, from the construction of telescopes to the analysis of the collected data, and participate in videoconferences, workshops, and masterclasses. The know-how developed as part of this project made possible the creation of sophisticated, portable cosmic-ray detectors, used in the PolarQuest2018 and PolarquEEEst-2019 expeditions. These detectors will make it possible to carry out new experimental measurements at arctic latitudes.
The Extreme Energy Events (EEE) Project is a joint effort between CREF and INFN. It is a scientific experiment with a twofold goal: on the one hand, it is devoted to the study of the secondary cosmic radiation at the ground level and on the other to the dissemination of science in high schools. The peculiarity of the EEE project is its geographical extension: The detectors are distributed throughout the whole Italian territory. EEE is also the largest experiment—in terms of total surface—based on the Multi-Gap Resistive Plate Chamber (MRPC) technology. However, the most relevant feature characterizing the uniqueness of this project is represented by the participation of secondary school students, who are directly and actively involved in all the phases of the experiment.
The EEE network currently includes 60 cosmic muon tracking telescopes, each consisting of three MPRC detectors (arranged one above the other at a distance of 50 cm). The MRPC detectors are built at CERN by teams of teachers and students and installed in high schools, universities and public research centers (CREF, INFN sections), spread out across Italy. The data acquired by the individual telescopes are used to study the characteristics of the local flux of secondary cosmic rays such as variations of flux as a function of environmental parameters—temperature and atmospheric pressure—or parameters associated with solar events, or absorption effects due to nearby or more distant obstacles (e.g., the Moon or the Sun), or to the east–west asymmetry.
The EEE Project telescopes are equipped with a GPS receiver that associates an absolute time to each detected cosmic ray, providing time synchronization between various telescopes. Thanks to the synchronization, it is possible to study extensive air showers and then search for events in time coincidence between stations at distances up to a few km. The detectors are distributed throughout Italy in clusters or in single stations. The large area covered by the network provides the possibility, unique in the world, to search for correlations between stations located hundreds of km apart. Any correlation signal from a distant telescope would be a direct indication of the production mechanisms hypothesized, but not yet experimentally verified, such as the Gerasimova–Zatsepin effect. The EEE experiment can provide a contribution in multi-messenger astronomy which is based on the simultaneous detection of different signals produced by the same astrophysical object or phenomenon: from photons, to charged and neutral particles, or gravitational waves. The EEE network can detect anomalies in the cosmic ray flux simultaneous to events of astrophysical interest such as, for example, the emission of gravitational waves or Supernovae explosions.
The EEE Project plays, in an innovative way, an important role in the dissemination of scientific culture, involving students and teachers of about one hundred Italian high schools in all phases of the experiment: from the construction of the detectors at CERN to their maintenance once installed in the schools, as well as in the data acquisition and analysis phase. Currently, more than a thousand students from all over Italy participate in the EEE project each year.