The Extreme Energy Events HECR array: status and perspectives

The Extreme Energy Events Project is a synchronous sparse array of 52 tracking detectors for studying High Energy Cosmic Rays (HECR) and Cosmic Rays-related phenomena. The observatory is also meant to address Long Distance Correlation (LDC) phenomena: the network is deployed over a broad area covering 10 degrees in latitude and 11 in longitude. An overview of a set of preliminary results is given, extending from the study of local muon flux dependance on solar activity to the investigation of the upward-going component of muon flux traversing the EEE stations; from the search for anisotropies at the sub-TeV scale to the hints for observations of km-scale Extensive Air Shower (EAS).Comment: XXV ECRS 2016 Proceedings - eConf C16-09-04.

New Eco-gas mixtures for the Extreme Energy Events MRPCs: results and plans

The Extreme Energy Events observatory is an extended muon telescope array, covering more than 10 degrees both in latitude and longitude. Its 59 muon telescopes are equipped with tracking detectors based on Multigap Resistive Plate Chamber technology with time resolution of the order of a few hundred picoseconds. The recent restrictions on greenhouse gases demand studies for new gas mixtures in compliance with the relative requirements. Tetrafluoropropene is one of the candidates for tetrafluoroethane substitution, since it is characterized by a Global Warming Power around 300 times lower than the gas mixtures used up to now. Several mixtures have been tested, measuring efficiency curves, charge distributions, streamer fractions and time resolutions. Results are presented for the whole set of mixtures and operating conditions, %. A set of tests on a real EEE telescope, with cosmic muons, are being performed at the CERN-01 EEE telescope. The tests are focusing on identifying a mixture with good performance at the low rates typical of an EEE telescope.Comment: 8 pages, 6 figures, proceedings for the "XIV Workshop on Resistive Plate Chambers and Related Detectors" (19-23 February 2018), Puerto Vallarta, Jalisco State, Mexic

Study of ageing in glass MRPCs

The Multigap Resistive Plate Chamber (MRPC) is used in many experiments due to its excellent efficiency and time resolution. We have studied the ageing effect on MRPC's glass sheets. In particular we analysed an MRPC built with glass sheets that had been used for ten years in a cosmic ray study. We extracted the glass sheets from these old chambers and built a new MRPC chamber. We used different configurations; significant changes in the efficiency and time resolution have been observed

Time resolution measurements with SiPMs coupled to a scintillator

This paper reports on the results of time resolution measurements of detectors consisting of SiPMs coupled to a scintillator. The R&D; has been performed both in a cosmic-ray setup, at the Bologna INFN laboratories, and in a beam test, at the CERN T10 beam line. Different couplings, direct or by means of optical fibres, have been tested. The measurements indicate that to reach better time resolutions, it is important to have a direct coupling between the SiPM and the scintillator. A time resolution of 67 ps has been achieved, for the direct coupling, broadened by the full electronics chain jitter

Operation and performance of the EEE network array for the detection of cosmic rays

The EEE (Extreme Energy Events) Project is an experiment for the detection of cosmic ray muons by means of a sparse array of telescopes, each made of three Multigap Resistive Plate Chambers (MRPC), distributed over all the Italian territory and at CERN. The main scientific goals of the Project are the investigation of the properties of the local muon flux, the detection of Extensive Air Showers (EAS) and the search for long-distance correlations between far telescopes. The Project is also characterized by a strong educational and outreach aspect since the telescopes are managed by teams of students and teachers who had previously constructed them at CERN. In this paper an overall description of the experiment is given, including the design, construction and performance of the telescopes. The operation of the whole array, which currently consists of more than 50 telescopes, is also presented by showing the most recent physics results

The EEE Project: a sparse array of telescopes for the measurement of cosmic ray muons

The Extreme Energy Events (EEE) Project is meant to be the most extensive experiment to detect secondary cosmic particles in Italy. To this aim, more than 50 telescopes have been built at CERN and installed in high schools distributed all over the Italian territory. Each EEE telescope comprises three large area Multigap Resistive Plate Chambers (MRPCs) and is capable of reconstructing the trajectories of the charged particles traversing it with a good angular resolution. The excellent performance of the EEE telescopes allows a large variety of studies, from measuring the local muon flux in a single telescope, to detecting extensive air showers producing time correlations in the same metropolitan area, to searching for large-scale correlations between showers detected in telescopes tens, hundreds or thousands of kilometers apart. In addition to its scientific goal, the EEE Project also has an educational and outreach objective, its aim being to motivate young people by involving them directly in a real experiment. High school students and teachers are involved in the construction, testing and start-up of the EEE telescope in their school, then in its maintenance and data-acquisition, and later in the analysis of the data. During the last couple of years a great boost has been given to the EEE Project through the organization of simultaneous and centralized data taking with the whole telescope array. The raw data from all telescopes are transferred to CNAF (Bologna), where they are reconstructed and stored. The data are currently being analyzed, looking at various topics: variation of the rate of cosmic muons with time, upward going muons, muon lifetime, search for anisotropies in the muon angular distribution and for time coincidences between stations. In this paper an overall description of the experiment is given, including the design, construction and performance of the telescopes. The operation of the whole array is also presented by showing the most recent physics results

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 â\u80\u9cEnrico Fermiâ\u80\u9d 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

The new trigger/GPS module for the EEE project

The Extreme Energy Events Project is an experiment devoted to the study of the Extensive Atmospheric Showers (EAS) which consists of a network of Multigap Resistive Plate Chambers (MRPCs) muon telescopes distributed over a very large area [Formula presented]. It requires a precise time synchronization to correlate the information collected from each single detector. The data acquisition system of each telescope is equipped with a trigger unit and a GPS receiver to perform precision timing of events. The Global Positioning System (GPS) unit provides the one pulse per second signal (1PPS) which is used to create a timestamp in UTC time. A novel VME trigger unit for the EEE telescopes was developed, including an embedded GPS engine for timing application. The trigger/GPS unit is presented, including some preliminary measurements of its time resolution

New Eco-gas mixtures for the Extreme Energy Events MRPCs: results and plans

The Extreme Energy Events observatory is an extended muon telescope array, covering more than 10 degrees both in latitude and longitude. Its 59 muon telescopes are equipped with tracking detectors based on Multigap Resistive Plate Chamber technology with time resolution of the order of a few hundred picoseconds. The recent restrictions on greenhouse gases demand studies for new gas mixtures in compliance with the relative requirements. Tetrafluoropropene is one of the candidates for tetrafluoroethane substitution, since it is characterized by a Global Warming Potential around 300 times lower than the gas mixtures used up to now. Several mixtures have been tested, measuring efficiency curves, charge distributions, streamer fractions and time resolutions. Results are presented for the whole set of mixtures and operating conditions, focusing on identifying a mixture with good performance at the low rates typical of an EEE telescope.The Extreme Energy Events observatory is an extended muon telescope array, covering more than 10 degrees both in latitude and longitude. Its 59 muon telescopes are equipped with tracking detectors based on Multigap Resistive Plate Chamber technology with time resolution of the order of a few hundred picoseconds. The recent restrictions on greenhouse gases demand studies for new gas mixtures in compliance with the relative requirements. Tetrafluoropropene is one of the candidates for tetrafluoroethane substitution, since it is characterized by a Global Warming Power around 300 times lower than the gas mixtures used up to now. Several mixtures have been tested, measuring efficiency curves, charge distributions, streamer fractions and time resolutions. Results are presented for the whole set of mixtures and operating conditions, %. A set of tests on a real EEE telescope, with cosmic muons, are being performed at the CERN-01 EEE telescope. The tests are focusing on identifying a mixture with good performance at the low rates typical of an EEE telescope