1,081 research outputs found

    A new method based on noise counting to monitor the frontend electronics of the LHCb muon detector

    Full text link
    A new method has been developed to check the correct behaviour of the frontend electronics of the LHCb muon detector. This method is based on the measurement of the electronic noise rate at different thresholds of the frontend discriminator. The method was used to choose the optimal discriminator thresholds. A procedure based on this method was implemented in the detector control system and allowed the detection of a small percentage of frontend channels which had deteriorated. A Monte Carlo simulation has been performed to check the validity of the method

    Study of the performance of the LHCb MWPC with cosmic rays

    Get PDF
    In this note we report the results of measurements performed with cosmic rays on different LHCb Muon Chambers. The main characteristics of the chambers have been investigated as a function of the high voltage value in order to achieve a better comprehension of the detector performance both for optimizing the chamber working conditions on the experimental apparatus and for providing useful information for the Monte Carlo simulation

    On the (in)dependence of the Dedekind-Peano axioms for natural numbers

    Get PDF

    Front-end Electronics Test for the LHCb Muon Wire Chambers

    Get PDF
    This document describes the apparatus and procedures implemented to test Multi Wire Proportional Chambers (MWPC) after front-end assembly for the LHCb Muon Detector. Results of measurements of key noise parameters are also described. Given a fully equipped chamber, this system is able to diagnose every channel performing an analysis of front-end output drivers’ response and noise rate versus threshold. Besides, it allows to assess if the noise rate at the experiment threshold region is within appropriate limits. Aiming at an automatic, fast and user-friendly system for mass production tests of MWPC, the project has foreseen as well electronic identification of every chamber and front-end board, and data archiving in such a way to make it available to the Experiment Control System (ECS) while in operation

    Molecular identification of Pichia guilliermondii, Debaryomyces hansenii and Candida palmioleophila

    Get PDF
    Traditional phenotypic methods and commercial kits based on carbohydrate assimilation patterns are unable to consistently distinguish among isolates of Pichia guilliermondii, Debaryomyces hansenii and Candida palmioleophila. As result, these species are often misidentified. In this work, we established a reliable method for the identification/differentiation of these species. Our assay was validated by DNA sequencing of the polymorphic region used in a real-time PCR assay driven by species-specific probes targeted to the fungal ITS 1 region. This assay provides a new tool for pathogen identification and for epidemiological, drug resistance and virulence studies of these organisms

    Customer service orientation on adhesion contracts

    Get PDF
    Hiring a service is a moment of great importance once it builds the perception of the service value and quality. Some companies may deal with that, assuming a greater importance when elaborating their service contracts. Usually law professional people elaborate these documents, but this may include legal attributes, not considering the service to the customers, as well as the customers’ point of view. In times of increasing on customer focus, market and service orientation, a question can be posted: to what extent company contracts show service or customer orientation? This paper compares the service orientation degree for Cable TV contracts from five companies, based on a theoretical model developed to this purpose. From a conceptual model for servant contract, four dimensions were assessed: physical aspects, reasonableness, intelligibility and customer focus. After subject evaluation by eight judges, analyzing the validation index (CVI), it was found that the contracts show moderate orientation to serve. Furthermore, results show that the five surveyed company’s contracts showed a similar overall performance, i.e., none stood out over the other. The study presents important practical efficacy, because it can guide the Cable TV companies to adopt improvement strategies in elaboration of contracts, so that the contractual instruments be would reviewed of clauses that promote the sensation of better service to their customer. Thus, this article directs the manager to the aspect that deserves more attention, i.e, which dimensions require further refinement and direction to serv

    Intermittent reconnection and plasmoids in UV bursts in the low solar atmosphere

    Full text link
    Magnetic reconnection is thought to drive a wide variety of dynamic phenomena in the solar atmosphere. Yet the detailed physical mechanisms driving reconnection are difficult to discern in the remote sensing observations that are used to study the solar atmosphere. In this paper we exploit the high-resolution instruments Interface Region Imaging Spectrograph (IRIS) and the new CHROMIS Fabry-Perot instrument at the Swedish 1-m Solar Telescope (SST) to identify the intermittency of magnetic reconnection and its association with the formation of plasmoids in so-called UV bursts in the low solar atmosphere. The Si IV 1403A UV burst spectra from the transition region show evidence of highly broadened line profiles with often non-Gaussian and triangular shapes, in addition to signatures of bidirectional flows. Such profiles had previously been linked, in idealized numerical simulations, to magnetic reconnection driven by the plasmoid instability. Simultaneous CHROMIS images in the chromospheric Ca II K 3934A line now provide compelling evidence for the presence of plasmoids, by revealing highly dynamic and rapidly moving brightenings that are smaller than 0.2 arcsec and that evolve on timescales of order seconds. Our interpretation of the observations is supported by detailed comparisons with synthetic observables from advanced numerical simulations of magnetic reconnection and associated plasmoids in the chromosphere. Our results highlight how subarcsecond imaging spectroscopy sensitive to a wide range of temperatures combined with advanced numerical simulations that are realistic enough to compare with observations can directly reveal the small-scale physical processes that drive the wide range of phenomena in the solar atmosphere.Comment: Accepted for publication in Astrophysical Journal Letters. Movies are available at http://folk.uio.no/rouppe/plasmoids_chromis

    Toxicidade de agrotóxicos utilizados em tomateiro ao parasitoide de ovos Trichogramma pretiosum (Hym.: Trichogrammatidae).

    Get PDF
    Objetivou-se com o presente trabalho avaliar a toxicidade dos inseticidas, dos fungicidas e dos herbicidas recomendados para o controle de insetos, doenças e plantas daninhas na cultura do tomateiro.Resumo expandido
    corecore