The Neutrino Platform (NP) is the CERN venture to foster and support the next generation of accelerator-based neutrino oscillation experiments. Part of the present CERN Medium-Term Plan, the NP ...provides facilities to develop and prototype the next generation of neutrino detectors while contributing to unify the European neutrino community towards the US and Japanese projects. A significative effort is made on R&D for LAr TPC technologies: two big LAr TPC prototypes for the DUNE far detector are under construction at CERN. Those detectors will be exposed in summer 2018 to an entirely new and NP-dedicated beam-line from the SPS which will provide electron, muon and hadron beams with energies in the range of sub-GeV to a few GeV. The total raw data volume that is slated to be collected during the scheduled 3-month beam run is estimated to be in excess of 2.5 PB for each detector. In this paper, the current status of NP Computing Infrastructure approach is presented to solving these problems by leveraging the design, expertise and components into a unified architecture that is capable of meeting the needs of NP prototypes experiments.
Data Acquisition (DAQ) and Data Quality Monitoring (DQM) are key parts in the HEP data chain, where the data are processed and analyzed to obtain accurate monitoring quality indicators. Such stages ...are complex, including an intense processing work-flow and requiring a high degree of interoperability between software and hardware facilities. Data recorded by DAQ sensors and devices are sampled to perform live (and offline) DQM of the status of the detector during data collection providing to the system and scientists the ability to identify problems with extremely low latency, minimizing the amount of data that would otherwise be unsuitable for physical analysis. DQM stage performs a large set of operations (Fast Fourier Transform (FFT), clustering, classification algorithms, Region of Interest, particles tracking, etc.) involving the use of computing resources and time, depending on the number of events of the experiment, sampling data, complexity of the tasks or the quality performance. The objective of our work is to show a proposal with aim of developing a general optimization of the DQM stage considering all these elements. Techniques based on computational intelligence like EA can help improve the performance and therefore achieve an optimization of task scheduling in DQM.
The ATLAS detector, currently being installed at CERN, is designed to make precise measurements of 14 TeV proton-proton collisions at the LHC, starting in 2007. Arguably the clearest signatures for ...new physics, including the Higgs boson and supersymmetry, will involve the production of isolated final-stated muons. The identification and precise reconstruction of muons are performed using a combination of detector components, including the Inner Detector, comprising a silicon tracker, pixel detector, and transition radiation tracker, housed in a uniform solenoidal field, and the precision standalone Muon Spectrometer, comprising monitored drift tubes and cathode strip chambers, triggered by resistive plate chambers and thin-gap chambers, and housed in a toroidal field. In order to manage the complexity and to understand the performance of the ATLAS Muon Spectrometer, a detailed full detector simulation is required and it should be kept under control by means of automatic validation procedures. We describe the implementation and the functionalities of the recently developed MuonValidation package, which has been developed as a dedicated tool to monitor and validate the performance of the Full simulation and digitization of the Muon System. Its flexible design allows comparisons between different Muon Spectrometer geometrical layouts and different software releases. Validation results based on fully simulated Geant4 events, using the complete detailed geometrical description of the detector, are shown.
The ATLAS detector is designed to exploit the full potential of the LHC, identifying and providing highly accurate energy and momentum measurements of particles emerging from the LHC proton–proton ...collisions. High-momentum final-state muons are among the most promising signatures at the LHC, thanks to a high-resolution Muon Spectrometer with standalone triggering and momentum measurement. The Muon Spectrometer is a large and complex system of gaseous detectors, requiring a detailed simulation to exploit its full capabilities. Over the last few years these systems have been described in terms of a set of geometrical primitives known as GeoModel. This description is now used in the GEANT4-based simulation program, which is fully operational and integrated into the ATLAS common analysis framework.
The implementation of run-time dependent corrections for alignment and distortions in the detector description of the ATLAS Muon Spectrometer is discussed, along with the strategies for studying such ...effects in dedicated simulations.
The study of the Z Boson and its decay into two muons at ATLAS provides several interesting aspects. Since the mass and the width of the Z-Boson is known to a very high precision from LEP ...experiments, Z decays can be used for precision tests of the detector, in particular for alignment issues. Various effects of misalignments in the ATLAS Muon Spectrometer on the reconstructed Z-Boson resonance are discussed. Moreover, the impacts on the precision of muon momentum reconstruction were studied.
We calculate the two-loop contributions to the electric dipole moments of the electron and the neutron mediated by charged Higgs in a generic supersymmetric theories. The new contributions are ...originated from the potential CP violation in the trilinear couplings of the charged Higgs bosons to the scalar-top or the scalar-bottom quarks. These couplings did not receive stringent constraints directly. We find observable effects for a sizable portion of the parameter space related to the third generation scalar-quarks in the minimal supersymmetric standard model.
Measurements are presented of R_b, the ratio of the b bbar cross-section to the q qbar cross-section in e+e- collisions, and the forward-backward asymmetry A^b_FB at twelve energy points in the range ...sqrt(s) = 130-207 GeV. These results are found to be consistent with the Standard Model expectations. The measurements are used to set limits on new physics scenarios involving contact interactions.
Motivated by the high muon momentum resolution and identification efficiency achievable with the ATLAS detector, currently being installed at CERN, we explore the observability of the supersymmetric ...h/A/H decays to two muons. The high experimental resolution in this decay mode compensates to some extent for the suppression of the branching ratio, with respect to the h/A/H → τ τ decays. The search is performed in a wide Higgs mass range, starting from 110 GeV/c2. In the case of gg → bb(h/H/A) production mode, the additional b-jets produced in association with the h/H/A bosons are used to suppress the background. Using fully simulated signal and background event samples, we study the performance of the reconstruction algorithms relevant to the analysis, such as the muon reconstruction, b-tagging and the measurement of the missing energy. The influence of the detector misalignment on the reconstruction performance is also taken into consideration. Emphasis is given on the optimization of the event selection procedure and the corresponding selection criteria, taking into account the different background composition depending on the mass range in which the Higgs search is performed.
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