The muon telescopes of the Extreme Energy Events (EEE) experiment are based on Multigap Resistive Plate Chambers (MRPC). The EEE network is composed, so far, of 53 telescopes, each made of three MRPC ...detectors; it is organized in clusters and single telescope stations distributed all over the Italian territory and installed in High Schools, covering an area larger than 3×105 km2. The study of Extensive Air Showers (EAS), that is one of the goal of the project, requires excellent performance in terms of time and spatial resolution, efficiency, tracking capability and long term stability. The data from two recent coordinated data taking periods, named Run 2 and Run 3, have been used to measure these quantities and the results are here reported, together with a comparison with expectations and with the results from a beam test performed in 2006 at CERN.
The new Trigger/GPS module for the extreme energy events project Abbrescia, M.; Avanzini, C.; Baek, Y. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2019, Volume:
942
Journal Article
Peer reviewed
Open access
The Extreme Energy Event (EEE) project is an experiment devoted to the study of high energy Extensive Air Showers (EAS) over a very large area, using an array of muon telescopes. At present the array ...is composed of more than 50 stations, most of them distributed across the Italian territory, on a total area of around 3×105km2. The telescopes are based on position-sensitive Multi-gap Resistive Plate Chambers (MRPCs) whose readout strips are connected to two TDC (Time-to-Digital Converter) units. Here a novel VME trigger unit for the EEE telescopes is presented, which also includes an embedded GPS receiver for precision timing applications. This new unit gets together, in the same electronic board, the functionalities of different parts of the electronics used up to now in the EEE experiment, and adds new ones, making the whole readout system simpler, more flexible and robust. Details about the trigger/GPS unit, including some measurements of its time resolution, are reported here.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
The Extreme Energy Events experiment (EEE) is a cosmic ray observatory made of about 60 muon telescopes based on Multigap Resistive Plate Chamber (MRPC) detectors. The EEE experiment has two ...main targets: a scientific and a dissemination. The EEE collaboration has also developed a large set of portable scintillator-based detectors, named Cosmic Box (CB), mainly used for educational purposes. The CB allows students to perform cosmic ray counting measurements in several environments. CBs are made of two 15 × 15 × 1 cm scintillators read by two 3 × 3 mm
2
SiPMs operated in coincidence. Three CBs were deployed in Nuraxi Figus and Seruci coal mine to perform an underground measurement of the cosmic muon flux attenuation. High school and university students were directly involved in all the stages of the measurements: from the preliminary measurements to the on-site work and data analysis.
The Extreme Energy Events (EEE) Project is devoted to the detection and study of high-energy cosmic rays. It is a network of 53 muon tracking telescopes made of three Multigap Resistive Plate ...Chambers (MRPC), synchronized by GPS and installed inside high schools distributed on the Italian territory. The EEE Project foresees also the direct involvement of students and teachers in the experiment, from the construction of the detectors to the maintenance, data taking and data analysis. The schools are unconventional experimental sites and a unique test field to check the performance of the MRPC technology. Data from recent coordinated data taking periods have been used to measure the performances and the results of this study are here reported.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The ratio Rη=Γ(η→π+π−γ)/Γ(η→π+π−π0) has been measured by analysing 22 million ϕ→ηγ decays collected by the KLOE experiment at DAΦNE, corresponding to an integrated luminosity of 558 pb−1. The η→π+π−γ ...proceeds both via the ρ resonant contribution, and possibly a non-resonant direct term, connected to the box anomaly. Our result, Rη=0.1856±0.0005stat±0.0028syst, points out a sizable contribution of the direct term to the total width. The di-pion invariant mass for the η→π+π−γ decay could be described in a model-independent approach in terms of a single free parameter, α. The determined value of the parameter α is α=(1.32±0.08stat−0.09syst+0.10±0.02theo) GeV−2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We have studied the vector to pseudoscalar conversion decay ϕ→ηe+e−, with η→π0π0π0, with the KLOE detector at DAΦNE. The data set of 1.7 fb−1 of e+e− collisions at s∼Mϕ contains a clear conversion ...decay signal of ∼31,000 events from which we measured a value of BR(ϕ→ηe+e−)=(1.075±0.007±0.038)×10−4. The same sample is used to determine the transition form factor by a fit to the e+e− invariant mass spectrum, obtaining bϕη=(1.28±0.10−0.08+0.09) GeV−2, that improves by a factor of five the precision of the previous measurement and is in good agreement with VMD expectations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A simulation tool based on GEMC framework to describe the MRPC telescope of the Extreme Energy Events (EEE) Project is presented. The EEE experiment is mainly devoted to the study of the secondary ...cosmic muons by using MRPC telescope distributed in high schools and research centres in Italy and at CERN. This takes into account the muon interactions with EEE telescopes and the structures surrounding the experimental apparata; it consists of a dedicated event generator producing realistic muon distribution and a detailed geometry description of the detector. Microscopic behaviour of MRPCs has been included to produce experimental-like data. A method to estimate the chamber efficiency directly from data has been implemented and tested by comparing the experimental and simulated polar angle distribution of muons.
The Extreme Energy Events (EEE) Project employs Multi-gap Resistive Plate Chambers (MRPCs) for studying the secondary cosmic ray muons in Extensive Air Showers. The array consists of about 60 ...tracking detectors, sparse on Italian territory and at CERN. The MRPCs are flowed with a gas mixture based on C2H2F4 and SF6, both of which are fluorinated greenhouse gases with a high environmental impact on the atmosphere. Due to the restrictions imposed by the European Union, these gases are being phased out of production and their cost is largely increasing. The EEE Collaboration started a campaign to reduce the gas emission from its array with the aim of containing costs and decreasing the experiment global warming impact. One method is to reduce the gas rate in each EEE detector. Another is to develop a gas recirculation system, whose prototype has been installed at one of the EEE stations located at CERN. Jointly a parallel strategy is focused on searching for environmental friendly gas mixtures which are able to substitute the standard mixture without affecting the MRPC performance. An overview and the first results are presented here.
Results from the PolarquEEEst missions Abbrescia, M.; Avanzini, C.; Balbi, G. ...
Journal of physics. Conference series,
06/2020, Volume:
1561, Issue:
1
Journal Article
Peer reviewed
Open access
The PolarquEEEst scientific programme consists in a series of measurements of the cosmic ray flux up to the highest latitudes. It started in Summer 2018, when three telescopes made out of ...scintillators readout by SiPMs were built and installed in Italy, Norway and on a sailboat leaving from North Island, to circumnavigate the Svalbard archipelago and land in Tromsø. They collected data on a latitude range from 44° N up to 82° N, with a dense sampling of the Northernmost interval. The PolarquEEEst mission continued afterwards with a series of measurements in Italy, Southward reaching Lampedusa, and in Germany. In May 2019 the PolarquEEEst collaboration accomplished another important result, installing a cosmic ray observatory for the detection of secondary cosmic muons at Ny Alesund, at 79° N, made of three independent identical detectors positioned a few hundred meters from each other, and synchronized in order to operate together as a network. The configuration used will allow high precision measurements never performed before at these latitudes on a long term, also interesting for their connection with environmental phenomena. The network will also complement the existing stations for the detection of cosmic neutrons at the Svalbard archipelago, enlarging by far the physics scope that is possible to pursue in this field at this peculiar location. Here the various missions are presented, and some preliminary results from the measurements performed are shown.
The existence of time correlations in detectors separated by distances much larger than the size of the highest energy extensive air showers (EAS) has been long discussed over the years. Several ...mechanisms have been proposed to justify the existence of such events and, in the last decade, some experiments have also tried to search for correlations on a large scale distance, beyond one hundred kilometers. The approaches were based on the construction of clusters of detectors placed at large relative distances, with the capability of selecting extensive air showers.
Within this context, the Extreme Energy Events (EEE) experiment can provide new inputs in the search for long distance correlations, thanks to its sparse array of muon telescopes spanning all the Italian territory.
The EEE telescopes are taking data since more than 10 years and enough statistics has been already accumulated to be able to search for such events, whose observation is intrinsically difficult due to the very low rates expected, many order of magnitudes smaller than the overall cosmic ray flux. In order to reduce the accidental correlations, different analysis approaches have been investigated for the selection of EAS events with the EEE telescopes. In this paper we will present preliminary results obtained by analyzing a large fraction of the statistics currently available.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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