The objective of the EEE Project is to create a scientific experiment on cosmic rays and bring it into Italian high schools to engage young students and promote the spread of scientific culture. Specifically, the project aims to study the muons generated by the interaction of primary cosmic rays (mainly protons) with the Earth’s atmosphere, using a dedicated experimental setup. Muons, being penetrating particles, can be detected even inside school buildings, which are transformed into laboratories for subnuclear physics.

Therefore, the EEE Project involves the construction and installation of muon tracking detectors, called telescopes, throughout the national territory. This approach allows the project to involve the largest possible number of schools, enabling the study of cosmic ray flux characteristics on a local basis while also making it possible to study potential correlations between events across the entire network. EEE is a unique nationwide cosmic ray observatory that, through constant monitoring of cosmic radiation, allows for multidisciplinary and STEM-focused studies. Schools can join the EEE Project even without installing a telescope on-site; they become part of a network and can perform analyses on any dataset. The launch of the PolarquEEEst mission represents a further development of the EEE Project’s monitoring network.

Through this organization, students and teachers are fully involved in every phase of the experiment, from the construction of the detectors to the analysis of the acquired data. Since the pilot phase began in 2005 with a few schools, the project has grown to include about 70 schools actively participating each year, involving a large number of students from all over Italy. Both remote and in-person meetings provide an additional educational opportunity for students to interact and compare notes.

The EEE Project consists of a network of cosmic ray tracking telescopes, each made up of three large-area Multigap Resistive Plate Chamber (MRPC) detectors (2 m2). On the right side of the figure below, one of the telescopes is shown. The EEE network currently consists of around 50 telescopes, making EEE the most extensive cosmic ray observatory based on MRPC technology. On the left side of the figure below, the geographical distribution of participating schools is shown: the red and orange circles indicate the locations of the school-based and INFN-based telescopes, respectively, while the light blue circles show participating schools without a telescope. The figure also includes

As previously mentioned, student involvement begins with the construction of the detectors at CERN and continues with their installation in schools, universities, and public research bodies (CREF, INFN sections).

The data acquired by the individual telescopes allow us to study the characteristics of the local flux of secondary cosmic rays. Each telescope can measure the point of passage of muons on each chamber with a precision of 1 cm2 to obtain the particle’s track and direction. A GPS receiver synchronizes the telescopes, allowing us to study correlations between nearby stations (study of extensive atmospheric showers for stations up to a few kilometers apart) and even very distant ones, for studies on events like solar storms. The geographical distribution of the detectors, organized in clusters or single stations, offers a unique opportunity to directly search for correlations between stations located hundreds of kilometers apart. A positive signal would directly indicate a hypothesized mechanism that has not yet been verified experimentally.

Since 2014, the EEE Project has been organized into coordinated data acquisition phases called “Runs,” which coincide with the academic year. During this period, the network’s telescopes operate simultaneously, with maximum attention paid to their functioning to ensure the observatory’s highest efficiency. To this end, students and teachers participate in periodic meetings, the “Run Coordination Meetings,” which provide and receive updates on the network’s status. Since 2022, after the COVID-19 emergency, the restart of the telescopes began using a new eco-friendly gas mixture that provides performance in line with the experiment’s requirements and does not necessitate major modifications to the installations. The following image shows the detection efficiency measured with the new mixture compared to the previous one.

The telescope restart phase, which also represents the additional challenge of an ecological transition, is still ongoing and will continue for the next two years. Despite the interruption (also due to the COVID-19 health emergency), the EEE Project continued to organize monthly online meetings, the Run Coordination Meetings, which are the primary forum for all participating students. The program for these meetings also includes seminars on topics not directly related to EEE Project activities. Hundreds of students usually attend the online Run Coordination Meetings (via individual or group connections). To date, activities on the telescopes have resumed in about 20 schools and in several INFN and CERN laboratories. The resumption of activities is visible on the experiment’s open monitor webpage (https://iatw.cnaf.infn.it/eee/monitor/) as shown in the following figure: after a period of activity stoppage characterized by a minimal increase in the number of tracks acquired, the statistics began to grow again starting in 2024 with the telescopes’ restart.

From November 27 to 29, 2024, through a Centro Fermi grant for schools participating in the E.E.E. Project, an in-person meeting was held at CREF with about 100 participants (following figure), most of whom were high school students. The meeting, which celebrated 20 years since the EEE Project was presented at CERN, took place in conjunction with the International Cosmic Day (organized by the DESY physics lab in Hamburg), an annual event that brings together schools from all over the world for a day of cosmic ray studies. The central event was a masterclass where students personally analyzed and then presented data acquired from various telescopes operating with the new gas mixtures.

The PolarquEEEst Mission was born out of the EEE Project. For this mission, three compact scintillation detectors were built with the involvement of Norwegian and Swiss high schools to study and monitor the cosmic ray flux at extreme latitudes: the POLA-R (POLA-01/02/03) detectors. In 2018, POLA-01 was installed aboard the boat Nanuq, which circumnavigated Svalbard, measuring the cosmic ray flux up to 82° N. The compact detector is also suitable for measurements on the move. In addition to various measurement campaigns by car, measurements have also been taken aboard the training ship “Amerigo Vespucci.” In 2019, thanks to the CNR’s collaboration, the three detectors were installed in Ny Alesund on the Svalbard Islands (Norway) at the Dirigibile Italia station for the continuous study and monitoring of the cosmic ray flux at extreme latitudes, as shown in the following figure from a preliminary analysis presented at the Cosmic-Ray International Studies and Multi-messenger Astroparticle Conference, CRIS-MAC 2024, held in Trapani from June 17 to 21, 2024. As can be seen, the measured rate from the functioning detectors shows an annual periodicity (the summer-winter effect); a possible decrease in the flux in accordance with the solar cycle is still being studied. The continuation of the measurement campaign in Ny Alesund will allow us to cover the entire duration of the solar cycle (11 years) and continue the ongoing periodicity studies.

In addition to their scientific importance, cosmic rays offer extraordinary educational opportunities for introducing young people to advanced concepts in modern physics. The idea behind the Extrem Energy Events (EEE) Project, presented by its creator Prof. A. Zichichi in 2004, is for Italian high school students to participate in every phase of a cosmic ray physics experiment, starting with the construction of the detector. This practical and interdisciplinary approach, which echoes the legacy of Enrico Fermi, not only stimulates interest in science but also encourages critical thinking and an understanding of the connections between microscopic phenomena and the large-scale universe.

Including the topic of cosmic rays in school curricula can transform learning into an engaging and formative experience, bringing young people closer to the frontiers of scientific research and inspiring a new generation of scientists. The opportunity to create a national network for monitoring cosmic radiation represents another element of training and scientific education through teamwork.