[en] The PeakSum Processing System (PSS) is an element of the neutral trigger of the NA48 experiment at CERN. The PSS is a pipelined processor based on a VLSI semi-custom device, containing all the processing blocks needed in the system. The PSS provides information on the energy pattern released in the electromagnetic calorimeter of the NA48 experiment, used to identify K₀ Right-arrow π⁰π⁰ Right-arrow 4γ decays

[en] A first level trigger system based on a 40 MHz digital pipeline has been developed for the CERN NA48 experiment, aiming at measuring CP violation in K⁰ → 2π decays. The outputs of the 13340 cells of the 10 m³ liquid krypton calorimeter are summed into 64 X and 64 Y projection strips and continuously digitized with 40 MHz FADCs. This information is used to reconstruct at each clock cycle and for the two calorimeter projections, the number of clusters, the impact time of each of them (with a precision of about 3 ns), their total energy and the first and second moments of the energy distribution. Based on the quantities listed above, a programmable look-up table system subsequently computes online the longitudinal position of the kaon decay vertex and performs an event selection. The system is described

[en] The Extreme Energy Events (EEE) experiment, dedicated to the study of secondary cosmic rays, is arguably the largest detector system in the world implemented by Multigap Resistive Plate Chambers. The EEE network consists of 60 telescopes distributed over all the Italian territory; each telescope is made of three MRPCs and allows to reconstruct the trajectory of cosmic muons with high efficiency and optimal angular resolution. A distinctive feature of the EEE network is that almost all telescopes are housed in High Schools and managed by groups of students and teachers, who previously took care of their construction at CERN. This peculiarity is a big plus for the experiment, which combines the scientific relevance of its objectives with effective outreach activities. The unconventional location of the detectors, mainly in standard classrooms of school buildings, with heterogeneous maintenance conditions and without controlled temperature and dedicated power lines, is a unique test field to verify the robustness, the low aging characteristics and the long-lasting performance of MRPC technology for particle monitoring and timing. Finally, it is reported how the spatial resolution, efficiency, tracking capability and stability of these chambers behave in time.

[en] The main goal of the KLOE experiment is the study of CP violation in the K mesons system, with an accuracy of 10^-4 in the measurement of Re(ε'/ε). This task imposes strong constraints on the design and operation of the drift chamber, which must reconstruct the charged decays of low momentum K_L's and K_S's with high efficiency and high resolution. A full-length prototype of the chamber has been built and tested on a 50 GeV/c beam. The analysis of the large sample of data has allowed a detailed study of the time to distance relations as a function of the track parameters and of the peculiar geometry of the drift cell. The detector performance, in terms of efficiency, spatial resolutions and dE/dx resolution, is illustrated and discussed. (orig.)

[en] After its successful campaign of measurements beyond the Polar Arctic Circle, the PolarquEEEst experiment measured the cosmic charged particle rate at sea level in a latitude interval between 35${}^{\circ <!--\; ???\; -->}$ N and 82${}^{\circ <!--\; ???\; -->}$ N. In this paper, these measurements are described and the corresponding results are discussed.

[en] The upcoming phase of expansion of the telescope network of the EEE project has recently inspired a proposal of redesign of the detector control and monitoring, as well as data acquisition interfaces. The new design results in a very compact and versatile system with a significant cost reduction. The system architecture is described, with emphasis on the integration of data acquisition, trigger and GPS into a single unit. Performances of a fully functional prototype are also reported, as well as plans for future developments

[en] The goal of the PolarquEEEst experiment was to measure the cosmic charged particle rate at latitudes greater than 66° N, where no systematic and accurate measurements at sea level have ever been performed. A latitude range well above the Arctic Circle was explored on board of a sailboat, up to the unprecedented northernmost value of 82°07′ N. In this paper a description of the experimental set-up is reported, then the procedures for calibration and data analysis are described in detail. The results show that the rate measured in this latitude range stays constant within a novel accuracy of ±1%.

[en] We report on a beam test of a small prototype of the KLOE drift chamber in magnetic field. The chamber was operated with a 90% He-10% iC₄H₁₀ gas mixture. Drift space-time relations were studied. The average spatial resolution is about 110 μm in the absence of magnetic field and 120 μm in a 0.6 T magnetic field. Measurements of the primary ionization and drift velocity are reported. The measurement of dE/dx in a He-based gas mixture is also discussed

[en] This paper describes the simulation framework of the extreme energy events (EEE) experiment. EEE is a network of cosmic muon trackers, each made of three multi-gap resistive plate chambers (MRPC), able to precisely measure the absolute muon crossing time and the muon integrated angular flux at the ground level. The response of a single MRPC and the combination of three chambers have been implemented in a GEANT4-based framework (GEMC) to study the telescope response. The detector geometry, as well as details about the surrounding materials and the location of the telescopes have been included in the simulations in order to realistically reproduce the experimental set-up of each telescope. A model based on the latest parametrization of the cosmic muon flux has been used to generate single muon events. After validating the framework by comparing simulations to selected EEE telescope data, it has been used to determine detector parameters not accessible by analysing experimental data only, such as detection efficiency, angular and spatial resolution.

[en] This paper discusses the possibility to employ the Multi-gap Resistive Plate Chambers (MRPC) of the Extreme Energy Events (EEE) Project as muon tracking detectors to monitor the long term stability of civil buildings and structures when used in conjunction with additional detectors, to reconstruct the average direction of the cosmic muon tracks passing through both devices and any small variation over long time acquisition periods. The performance of such setup is discussed and preliminary experimental coincidence results obtained with a 40× 60 cm² scintillator detector operated in the same building with one of the EEE telescopes, at about 15 m vertical distance from it, are presented. Simple Monte Carlo and GEANT simulations were also carried out to evaluate typical acceptance values for the operating conditions employed so far, to extrapolate to other geometrical configurations, and to evaluate multiple scattering effects.