Istituto Nazionale Di Fisica Nucleare Research Articles

Preface of the IPAC23 Proceedings

The 14th International Particle Accelerator Conference, IPAC’23, took place at the Venice Convention Centre, Venice, Italy, from Sunday to Friday, 7 to 12 May, 2023. The conference was hosted by the Elettra Sincrotrone Trieste (Elettra) and Istituto Nazionale di Fisica Nucleare (INFN) and organised under the auspices of the European Physical Society Accelerator Group (EPS-AG) and the International Union of Pure and Applied Physics (IUPAP). With its record participation, the highest number of submitted papers in an accelerator conference to date and the largest ever industrial exhibition, the conference covered a wide range of excellent results and projects in accelerator science, technology and industry. This proceedings volume includes the peer reviewed part of the papers that were presented at IPAC’23.

JUNO sensitivity on proton decay p → ν K + searches* *We are grateful for the ongoing cooperation from the China General Nuclear Power Group. This study was supported by the Chinese Academy of Sciences, the National Key R&D Program of China, the CAS Center for Excellence in Particle Physics, Wuyi University, and the Tsung-Dao Lee Institute of Shanghai Jiao

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via is 36.9% ± 4.9% with a background level of events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies.

Preface

The 2nd International Conference on Advances in Modern Physics Sciences and Engineering Technology - PSET 2023 has been held on April 29th-30th, 2023, in Wuhan, China. This conference is organized by the China University of Geosciences (Wuhan), China, and the Istituto Nazionale di Fisica Nucleare (INFN), in collaboration with Wuhan University, China, University of Huddersfield, UK, University of Messina, Italy, and University of Ferrara, Italy.The primary goal of this conference is to provide a platform for presenting the latest advancements and research findings in engineering technology and applied physics from around the world. We aspire to foster research opportunities and collaborations that will help to advance the fields of modern physics sciences and technologies, particularly for young scientists and engineers.This volume of proceedings comprises comprehensive research papers, experience reports, and empirical studies contributed by scholars from around the world. In total, 75 papers submitted to PSET2023 and 50 papers underwent a meticulous peer-review process, with each paper being evaluated by at least one expert in the relevant field. Following rigorous assessment for quality and originality, finally, 31 papers were chosen for inclusion in this volume for publication. These papers include research and development in various areas such as mechanical and materials science, industrial engineering technology and applications, simulation, modelling and optimization technologies. The conference showcased numerous informative technical papers, including groundbreaking research presented by participants from various institutions. It was a platform for state-of-the-art research, lively discussions, and friendly exchanges.We extend our heartfelt gratitude to all keynote speakers: Prof. Dr. Osman Adiguzel, Firat University, Turkey, Prof. Alexander G. Ramm, Kansas State University, USA and Prof. Shuifa Shen, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, China. Thank the international reviewers and program committee members for their valuable contributions and dedication in making this conference a success.We look forward to meeting you next year!Sergei KopeikinUniversity of Missouri, USARoberto ZivieriNational Institute of High Mathematics (INdAM), Rome, ItalyList of Internationals Committee Members are available in the pdf

Fast transient infrared detection for time-domain astronomy

Multi-messenger astronomy requires the use and development of telescopes and detectors for temporal observations across all the electromagnetic spectrum. The interest of our team is towards time-domain (or longitudinal, in the jargon of storage ring diagnostics) detectors able to make observations over the time rather than transversely by making photographs or spectrographs. The FAIRTEL (Fast InfraRed TELescope) experiment wants to build a very fast detector in the Mid InfraRed (MIR) to be used in time-domain astronomy. The experiment is oriented mainly toward the search of fast astronomical transients in the Galaxy, similarly to what has been observed in different electromagnetic ranges with the discovery of the FRBs (Fast Radio Burst) and the GRBs (Gamma-Ray Burst). In the last years, time-domain astronomy is growing in interest and intends to study events on time scales that can go from hundreds of milliseconds to microseconds and even shorter. The detector proposed by the FAIRTEL experiment, is based on HgCdTe semiconductors and on the experience done in the diagnostics for storage ring developed at DAFNE, the Italian e+/e− circular collider. The detection system design is in progress at the LNF (Laboratori Nazionali di Frascati) of INFN (Istituto Nazionale di Fisica Nucleare) while the telescope will be a standard reflecting type, like a Newtonian, a Cassegrain or a Ritchey–Chrétien telescope. The detection apparatus is under test at the IR synchrotron beamline SINBAD at DAFNE and it is foreseen to be implemented at the OPC (Osservatorio Polifunzionale del Chianti). It should be able to observe events with transients down to the nanosecond. A further development of the project involves the extension from ground-based observations to those by using balloons for scientific studies.

Ultra-fast infrared detector for astronomy

The advent of multi-messenger astronomy requires time-domain telescope detectors across the whole electromagnetic spectrum. Furthermore, astronomical fast transients such as FRBs (Fast Radio Bursts) and GRBs (Gamma Ray Bursts) lead to the concept of time-domain astronomy. FAIRTEL, an ultrafast infrared detector for ground-based telescopes, is under development thanks to funding from the Istituto Nazionale di Fisica Nucleare (INFN).

Performance of highly irradiated FBK planar and 3D pixel detectors

The High Luminosity upgrade of the CERN Large Hadron Collider (HL-LHC) requires new radiation tolerant silicon pixel sensors. In the case of the CMS experiment, the first layer of pixel detectors will be installed at about 3 cm from the beam line, where an integrated fluence of about 20×1015neqcm−2 (1 MeV equivalent neutrons) is expected (HL-LHC Runs 4 and 5). The first tracker layer will be substituted before the start of HL-LHC Run 6. The 3D concept for silicon pixel sensors presents several advantages with respect to traditional (planar) sensors. Thanks to short anode-to-cathode distances, 3D sensors are much more resistant to radiation damage, making them suitable for use in the inner layer of the future tracker. This paper describes results from beam tests with highly irradiated planar and 3D sensor and RD53A readout chip combinations. RD53A is the first prototype in 65 nm technology developed by the RD53 collaboration for use in HL-LHC pixel detectors. The sensors were made in FBK foundry in Trento, Italy, and their development was done in collaboration with INFN (Istituto Nazionale di Fisica Nucleare, Italy). Both planar and 3D sensors feature a pixel area of 2500 μm2 and an active thickness of 150 μm. The pixel detectors, irradiated to fluences up to 24×1015neqcm−2, were tested in the DESY test beam facility and the analysis of the data shows excellent performances even for the highest irradiation fluences. All results are obtained in the framework of the CMS R&D activities.

Sub-percent precision measurement of neutrino oscillation parameters with JUNO* *Supported by the Chinese Academy of Sciences, the National Key R&D Program of China, the CAS Center for Excellence in Particle Physics, Wuyi University, and the Tsung-Dao Lee Institute of Shanghai Jiao Tong University in China, the Institut National de Physique Nucléaire et de Physique de Particules (IN2P3) in France, the

JUNO is a multi-purpose neutrino observatory under construction in the south of China. This publication presents new sensitivity estimates for the measurement of the , , , and oscillation parameters using reactor antineutrinos, which is one of the primary physics goals of the experiment. The sensitivities are obtained using the best knowledge available to date on the location and overburden of the experimental site, the nuclear reactors in the surrounding area and beyond, the detector response uncertainties, and the reactor antineutrino spectral shape constraints expected from the TAO satellite detector. It is found that the and oscillation parameters will be determined to 0.5% precision or better in six years of data collection. In the same period, the parameter will be determined to about % precision for each mass ordering hypothesis. The new precision represents approximately an order of magnitude improvement over existing constraints for these three parameters.

Expected sensitivity to 128Te neutrinoless double beta decay with the CUORE TeO2 cryogenic bolometers

The CUORE experiment is a ton-scale array of hbox {TeO}_2 cryogenic bolometers located at the underground Laboratori Nazionali del Gran Sasso of Istituto Nazionale di Fisica Nucleare (INFN), in Italy. The CUORE detector consists of 988 crystals operated as source and detector at a base temperature of sim 10 mK. Such cryogenic temperature is reached and maintained by means of a custom built cryogen-free dilution cryostat, designed with the aim of minimizing the vibrational noise and the environmental radioactivity. The primary goal of CUORE is the search for neutrinoless double beta decay of ^{130}hbox {Te}, but thanks to its large target mass and ultra-low background it is suitable for the study of other rare processes as well, such as the neutrinoless double beta decay of ^{128}hbox {Te}. This tellurium isotope is an attractive candidate for the search of this process, due to its high natural isotopic abundance of 31.75%. The transition energy at (866.7 ± 0.7) keV lies in a highly populated region of the energy spectrum, dominated by the contribution of the two-neutrino double beta decay of ^{130}hbox {Te}. As the first ton-scale infrastructure operating cryogenic hbox {TeO}_2 bolometers in stable conditions, CUORE is able to achieve a factor >10 higher sensitivity to the neutrinoless double beta decay of this isotope with respect to past direct experiments.

Preface

With the successful organizing a series of world-class conferences, and a close cooperation among the University of Messina, Italy; University of Ferrara, Italy; Istituto Nazionale di Fisica Nucleare (INFN); Wuhan University, China, we have been making great efforts to hold the the 2022 First International Conference on Advances in Modern Physics Sciences and Engineering Technology-PSET 2022, which will be happened on March 5-6th 2022, in Beijing, China, organized by Wuhan University, China and Istituto Nazionale di Fisica Nucleare (INFN).3 sessions are included in PSET22: Applied Physics and Materials Engineering, Electrical Engineering and Automation, Engineering Technologies and Applications. This volume comprises 47 selected papers from 72 submissions, which introduces latest advancements in the subjects of applied physics, material sciences, modelling, simulation and design, optimization techniques, and their applications in real world for solving real problems. These contributions, which were selected by means of a rigorous international peer-review process, present a wealth of exciting ideas that will open novel research directions among specialists.Our vision is to be internationally recognized as one of the Internationally-leading Platform in the world’s physics community, pursuing excellence in research, education and knowledge transfer.We are all working to achieve highly goals. We foster research opportunities that will improve tomorrow’s physics sciences and modern engineering technologies, in cooperation with people from universities and industries all over the world, especially for the young scientists and engineers.PSET appreciates the invited spkeaers from different unviersities: Prof. Dr. Osman Adiguzel, Firat University, Elazig, Turkey; Prof. Alexander G. Ramm, Mathematics Department, Kansas State University, USA; Prof. Dr. Shuifa Shen, Institute of Nuclear Energy Safety Technology, Chinese Academy of Sciences, China; Prof. Dr. Bayram Gündüz, Department of Opticians, Malatya Turgut Ozal University,Turkey, who made great academic presentation for PSET participants. Meawhile, many thanks for authors who contributed their latest researches to PSET, the publishing editors and reviewers who made great effort on PSET22 conference proceedings, as well as the support from IOP Publishing and their publishing team.This volume of proceedings are beneficial for readers from both academia and industry to understand and tackle the challenges in an efficient manner and to adopt appropriate solutions in the mentioned fields above. Building on the success of previous conferences were held, we hope PSET will be one of the mostspectacular events in those areas.The Committee of PSET22Prof. Roberto ZivieriNational Institute of High Mathematics (INdAM), Rome, ItalyList of titles Committees Members, General Chairs, Honorary Chairs, Co-Chairs, Editors, International Committee Members are available in this Pdf.

Feasibility and physics potential of detecting 8B solar neutrinos at JUNO * *This work was supported by the Chinese Academy of Sciences, the National Key R&D Program of China, the CAS Center for Excellence in Particle Physics, the Joint Large-Scale Scientific Facility Funds of the NSFC and CAS, Wuyi University, and the Tsung-Dao Lee Institute of Shanghai Jiao Tong University

The Jiangmen Underground Neutrino Observatory (JUNO) features a 20 kt multi-purpose underground liquid scintillator sphere as its main detector. Some of JUNO's features make it an excellent location for B solar neutrino measurements, such as its low-energy threshold, high energy resolution compared with water Cherenkov detectors, and much larger target mass compared with previous liquid scintillator detectors. In this paper, we present a comprehensive assessment of JUNO's potential for detecting B solar neutrinos via the neutrino-electron elastic scattering process. A reduced 2 MeV threshold for the recoil electron energy is found to be achievable, assuming that the intrinsic radioactive background U and Th in the liquid scintillator can be controlled to 10 g/g. With ten years of data acquisition, approximately 60,000 signal and 30,000 background events are expected. This large sample will enable an examination of the distortion of the recoil electron spectrum that is dominated by the neutrino flavor transformation in the dense solar matter, which will shed new light on the inconsistency between the measured electron spectra and the predictions of the standard three-flavor neutrino oscillation framework. If eV , JUNO can provide evidence of neutrino oscillation in the Earth at approximately the 3 (2 ) level by measuring the non-zero signal rate variation with respect to the solar zenith angle. Moreover, JUNO can simultaneously measure using B solar neutrinos to a precision of 20% or better, depending on the central value, and to sub-percent precision using reactor antineutrinos. A comparison of these two measurements from the same detector will help understand the current mild inconsistency between the value of reported by solar neutrino experiments and the KamLAND experiment.

A Radiation-Tolerant, Multigigabit Serial Link Based on FPGAs

Multigigabit serial links implemented by means of static random access memory (SRAM)-based field-programmable gate arrays (FPGAs) are extensively used in trigger and data acquisition systems of high-energy physics experiments. Their usage is mostly in areas without radiation, due to the sensitivity of FPGA configuration memory to single-event upsets. In order to use these links in radiation environments, some mitigation techniques can be used. In this article, we present a bidirectional link running at 6.25 Gbps implemented in Xilinx Kintex-7 FPGAs. Transferred data are protected against radiation effects by means of a Reed-Solomon (RS) code and symbol interleaving. Logic features triple modular redundancy in critical blocks. The design includes a custom scrubber based on majority voting of configuration frames. Our custom protocol can vary the protection level of the RS code to cope with different rates of radiation-induced transmission errors, trading off the available bandwidth for reliability. We present the test results carried out using fault injection and a 62-MeV proton beam at the Istituto Nazionale di Fisica Nucleare (INFN) Laboratori Nazionali del Sud (Catania, Italy). We show the performance of the link in terms of mean time between failures and mean time between losses of lock.

Comparison between photon detection efficiency and tetraphenyl-butadiene coating stability of photomultiplier tubes immersed in liquid argon

Liquid argon detectors are an interesting option for neutrino experiments. The high density of liquid argon allows using it directly as target for neutrino interactions. The relatively large abundance of argon in the atmosphere makes it a cost-effective medium, allowing the construction of detectors of several hundred tons, such as ICARUS, and even several kton detectors are foreseen for the next generation of experiments, such as DUNE . Besides being suitable to act as the target, liquid argon also serves as the detection medium for the charged particles coming out of the interaction vertex. The interaction time, t0, can be determined by detecting the photons which are produced together with the electrons in the ionization process. To detect them, the integration of an efficient photon detection system into the liquid argon detector is necessary. One difficulty here is related to the fact that the emitted photons have a wavelength in the VUV range (128 nm). The classical approach for the photon detection system is, therefore, the usage of photomultiplier tubes coated with tetraphenyl-butadiene which shifts the VUV photons to about 430 nm, a wavelength to which the photomultiplier tubes are directly sensitive to. While the basic concept is well established and has been used in several experiments such as ICARUS, ArDM and DarkSide, some aspects of the coating are not well understood such as the preparation of the photomultiplier tube surface which can be either polished or sandblasted. To better understand the effect on the overall photon detection efficiency on one hand and the tetraphenyl-butadiene stability during the cooling down, on the other hand, the quantum efficiencies of sandblasted and polished photomultiplier tubes, coated following the same procedure, were measured with a setup at the Istituto Nazionale di Fisica Nucleare (INFN), in Pavia. In addition, the immersion of the photomultiplier tubes with different soak timings was tested, showing a significantly different behavior for fast and slow immersion for the polished photomultiplier tubes.

Performances of highly irradiated 3d and planar pixel sensors interconnected to the RD53A readout chip

The High Luminosity upgrade of the CERN Large Hadron Collider (HL-LHC) calls for new highly radiation tolerant silicon pixel sensors, capable of withstanding fluences up to 2.3 × 1016 neq/cm2 (1 MeV equivalent neutrons). In this paper results obtained in beam test experiments with 3D and planar pixel sensors interconnected with the RD53A readout chip are reported. RD53A is the first prototype in 65 nm technology issued by the RD53 collaboration for the future readout chip to be used in the upgraded pixel detectors. The interconnected modules have been tested in an electron beam at DESY, before and after irradiation, which was performed at the CERN IRRAD facility for the 3D sensors or at the KIT Irradiation Center for the planar sensors, up to an equivalent fluence of 1 × 1016 neq/cm2. The sensors were made by FBK foundry in Trento, Italy, and their development was done in collaboration with INFN (Istituto Nazionale di Fisica Nucleare, Italy). The analysis of the collected data shows hit detection efficiencies around 99% measured after irradiation. All results are obtained in the framework of the CMS R&D activities.

A peculiar didactical experience with the Pierre Auger Observatory outreach data

In this paper it will be described a peculiar educational experience with a classroom of Italian 17/18 years-old students during the competition “At school of Astroparticles” organized by Istituto Nazionale di Fisica Nucleare (INFN). It will also be shown how the action-research in scientific methodology formed an alternative, effective, and motivating approach to study physics. The students had significant advantages thanks to the information and the scientific data recorded by the Pierre Auger Observatory and transmitted to a computer in an accessible area to process via web. The teachers, researchers, and technicians of INFN were very helpful for the students to reconstruct extensive air showers (EAS) with computer software: the primary cosmic ray directions, the core of the EAS, the arrival times of secondary particle have been reconstructed with data available for outreach activities of the Pierre Auger Observatory, located in the Pampa Argentina on 3000 km2 of area and composed of a surface array of 1660 water Cherenkov tanks, and 27 fluorescence telescopes. This experience showed them an alternative captivating educational approach, having experienced the excitement of research, and having produced a scientific article, web page and a videogame. The success of the educational activity is reflected both in auto-cognitive books written by the students themselves and in skills achieved in checks during the experience.

A New Approach to Calorimetry in Space-Based Experiments for High-Energy Cosmic Rays

Precise measurements of the energy spectra and of the composition of cosmic rays in the PeV region could improve our knowledge regarding their origin, acceleration mechanism, propagation, and composition. At the present time, spectral measurements in this region are mainly derived from data collected by ground-based detectors, because of the very low particle rates at these energies. Unfortunately, these results are affected by the high uncertainties typical of indirect measurements, which depend on the complicated modeling of the interaction of the primary particle with the atmosphere. A space experiment dedicated to measurements in this energy region has to achieve a balance between the requirements of lightness and compactness, with that of a large acceptance to cope with the low particle rates. CaloCube is a four-year-old R&D project, approved and financed by the Istituto Nazionale di Fisica Nucleare (INFN) in 2014, aiming to optimize the design of a space-borne calorimeter. The large acceptance needed is obtained by maximizing the number of entrance windows, while thanks to its homogeneity and high segmentation this new detector achieves an excellent energy resolution and an enhanced separation power between hadrons and electrons. In order to optimize detector performances with respect to the total mass of the apparatus, comparative studies on different scintillating materials, different sizes of crystals, and different spacings among them have been performed making use of MonteCarlo simulations. In parallel to simulations studies, several prototypes instrumented with CsI(Tl) (Caesium Iodide, Tallium doped) cubic crystals have been constructed and tested with particle beams. Moreover, the last development of CaloCube, the Tracker-In-Calorimeter (TIC) project, financed by the INFN in 2018, is focused on the feasibility of including several silicon layers at different depths in the calorimeter in order to reconstruct the particle direction. In fact, an important requirement for γ -ray astronomy is to have a good angular resolution in order to allow precise identification of astrophysical sources in space. In respect to the traditional approach of using a tracker with passive material in front of the calorimeter, the TIC solution can save a significant amount of mass budget in a space satellite experiment, which can then be exploited to improve the acceptance and the resolution of the calorimeter. In this paper, the status of the project and perspectives for future developments are presented.

U-LITE, a Private Cloud Approach for Particle Physics Computing

The computing infrastructure of Laboratori Nazionali del Gran Sasso (LNGS) is the primary platform for data storage, analysis, computing and simulation of the LNGS-based experiments, which are part of the research activities of the Istituto Nazionale di Fisica Nucleare (INFN). Scientific collaborations running such experiments have diverse needs and adopt different approaches in developing the computing frameworks that support their activities. The emergence of resource virtualization and the cloud paradigm has allowed a complete change to the way of operating and managing the LNGS computing infrastructure, and realize U-LITE, a private versatile environment apt at hosting such varied ecosystem and providing LNGS scientific users a familiar computing interface which hides all the complexities of a modern data center management. Since 2011, U-LITE has proven to be a valuable tool for the LNGS experiments, and provides an example of effective use of a private Cloud computing approach in a real scientific context.

Construction and test of the SM1 MicroMegas chambers for the upgrade of the forward muon spectrometer of the ATLAS experiment

Abstract MICRO MEsh GASeous structure chambers, MicroMegas (MM (Giomataris et al., 1996 [1] )), is an innovative design concept for Micro-Pattern Gaseous Detectors, designed in order to provide a high spatial resolution and to cope with highly irradiated environments. These chambers have been chosen as new precision tracking detectors for the upgrade of the forward muon spectrometer of the ATLAS experiment during Long Shutdown 2 (LS2, 2019–2020). MM trapezoidal detector modules, with areas of 2–3 m 2 , will be part of the two New Small Wheels (NSW (ATLAS collaboration, 2013 [2] )) composing the innermost station of the ATLAS muon tracking system. ATLAS MM detectors are composed out of 4 read-out (RO) layers, two for the reconstruction of the precision coordinate and two with stereo reading ( ± 1 . 5 °) for the reconstruction of the second coordinate. MM chambers are designed to provide a resolution better that 100 μ m on the precision coordinate with an efficiency of at least 95% per single plane for a rate capability up to 15 kHz/cm 2 , in presence of magnetic fields up to 0.3 T. The Istituto Nazionale di Fisica Nucleare (INFN) is deeply involved in the construction of these chambers and their validation at the Cosmic Ray Stand (CRS) in the Frascati INFN site (LNF). Preliminary results on the tests performed on the INFN SM1 prototypes are presented. Copyright 2018 CERN for the benefit of the ATLAS Collaboration. CC-BY-4.0 license.

TNPI2016 - XV Conference on Theoretical Nuclear Physics in Italy

PrefaceThe present volume of the Journal of Physics: Conference Series contains the invited and contributed papers presented at the XV Conference on Theoretical Nuclear Physics in Italy (TNPI2016) held during April 20th – 22nd 2016 at the Physics Department “Enrico Fermi” of the University of Pisa (Italy).The aim of this conference is to bring together Italian theorists working in various fields of nuclear physics and related research areas to discuss their latest results and compare their points of view in a lively and informal way. This offers the opportunity to promote collaborations between different groups. There were about 40 participants at the conference, coming from various Italian Universities, from various “Sezioni” of the Istituto Nazionale di Fisica Nucleare (INFN) and from some non-Italian Institutions.List of Main Topics, Organizing Committees are available in this PDF

Searching Neutrinoless Double Beta Decay with Gerda Phase II

An observation of neutrinoless double beta ([Formula: see text]) decay would allow to shed light onto the nature of neutrinos. Gerda (GERmanium Detector Array) aims to discover this process in a background-free search using [Formula: see text]Ge. The experiment is located at the Laboratori Nazionali del Gran Sasso (LNGS) of the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. Bare, isotopically enriched, high purity germanium detectors are operated in liquid argon. Gerda follows a staged approach. In Phase II 35.6 kg of enriched germanium detectors are operated since December 2015. The application of active background rejection methods, such as a liquid argon scintillation light read-out and pulse shape discrimination of germanium detector signals, allows to reduce the background index to the intended level of [Formula: see text] cts/(keV⋅kg⋅yr). No evidence for the [Formula: see text] decay has been found in 23.2 kg⋅yr of Phase II data, and together with data from Phase I the up-to-date most stringent half-life limit for this process in [Formula: see text]Ge has been established, at a median sensitivity of 5.8⋅10[Formula: see text][Formula: see text]yr the 90[Formula: see text]% C.L. lower limit is 8.0⋅10[Formula: see text][Formula: see text]yr.

The EEE project – Science in schools: state and results

The Extreme Energy Events (EEE) project is an extended array for cosmic rays survey. It was conceived by Antonino Zichichi and supported by the Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi” with the collaboration of the European Organization for Nuclear Research (CERN), of the Istituto Nazionale di Fisica Nucleare (INFN) and of the Italian Ministry of Education, University and Research (MIUR). This experiment is aimed to study cosmic rays of extreme high energy, and related phenomena. To achieve this goal, a network of nearly 50 muon telescopes has been installed in high schools, distributed throughout the Italian territory, either as single stations or clusters. During the second coordinated run of data taking, which ended in May 2016, 25 billion muon tracks were detected and reconstructed. This huge amount of data, allows us to undertake various studies: the dependence of the local muon flux on solar activity; the sky anisotropy on sub-TeV scale; event correlations, due to EAS, between clustered telescopes at distances from a few hundred meters to over a kilometre. The status of the project and some results will be presented.