Strategies to reduce the environmental impact in the MRPC array of the EEE experiment

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.The Extreme Energy Events (EEE) Project employs Multi-gap Resistive Plate Chamber (MRPC) 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 $C_2H_2F_4$ and $SF_6$, 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 a first 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 first results are presented here.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

Recent results and performance of the multi-gap resistive plate chambers network for the EEE Project

The Extreme Energy Events (EEE) Project is devoted to the study of Extensive Atmospheric Showers through a network of muon telescopes, installed in High Schools, with the further aim of introducing young students to particle and astroparticle physics. Each telescope is a tracking detector composed of three Multi-gap Resistive Plate Chambers (MRPC) with an active area of 1.60 × 0.80 m(2). Their characteristics are similar to the ones built for the Time Of Flight array of the ALICE Experimentat LHC . The EEE Project started with a few pilot towns, where the telescopes have been taking data since 2008, and it has been constantly extended, reaching at present more than 50 MRPCs telescopes. They are spread across Italy with two additional stations at CERN, covering an area of around 3 × 10(5) km(2), with a total surface area for all the MRPCs of 190 m(2). A comprehensive description of the MRPCs network is reported here: efficiency, time and spatial resolution measured using cosmic rays hitting the telescopes. The most recent results on the detector and physics performance from a series of coordinated data acquisition periods are also presented