1,721,205 research outputs found
The detector for the MUonE experiment at CERN
No full textThe comparison between the measurement and the Standard Model prediction of the anomalous magnetic moment of the muon (aμ) is a way to search for physics beyond the Standard Model. Recently, the Fermilab Muon g−2 experiment measured aμ with a precision of 200 parts per billion (ppb), while the theoretical prediction of aμ is limited by the uncertainty in the leading-order hadronic vacuum-polarization contribution (aμHLO) as the two calculation methods, namely the dispersive approach and the lattice QCD, yield different results. The MUonE experiment proposes an alternative and independent way to precisely measure aμHLO through a unique direct measurement, which can be used to cross-check the theoretical value
Results from the Muon g-2 experiment at Fermilab
No full textThe goal of the Muon g-2 experiment at Fermilab is to measure the muon magnetic moment anomaly with a final accuracy of 140 parts per billion (ppb). The experiment has published two results based on the data collected in 2018 (Run-1) and 2019-2020 (Run-2/3), respectively. These results confirm the previous measurement performed 20 years ago at Brookhaven National Laboratory, and their combination reaches the unprecedented uncertainty of 200 ppb. This proceeding presents a brief overview of the Standard Model prediction for the muon g-2. It then summarizes the experimental measurement technique and the Run-1 and Run-2/3 measurements, detailing the improvements in their systematic and statistical uncertainties. Finally, it illustrates the comparison between theory and experiment and discusses future prospects
The calibration system of the muon g − 2 experiment at Fermilab
Full text linkThe Muon g − 2 experiment at Fermilab aims to measure the muon anomalous magnetic moment, aμ, to an unprecedented precision of 140 ppb. To reach this goal each channel of the 24 calorimeters must be calibrated with a relative accuracy at the sub-per-mill level. Such accuracy level is a challenge for the design of the calibration system because it has never been previously required and realized
The Muon g − 2 experiment
Full text linkMeasurements of the anomalous magnetic moment of the muon, aμ, with increased precision are motivated by the ∼ 3 standard deviation discrepancy between the most recent measurement performed at the Brookhaven National Laboratory (BNL) by the experiment E821 and the Standard-Model prediction. A brief summary of the current theoretical and experimental status is reported in these proceedings
Leakage Studies for a Dual Readout Calorimeter
No full textMeasuring the energy of jets with high precision is essential at present and future colliders. A calorimeter is designed to measure the total energy deposited by the particles in the jet. A problem arises from the fact in general, the calorimeter response for e± and γs is different com- pared to the response for hadrons and, since the relative proportions of the energies deposited by electromagnetic (e.m.) and hadronic interactions fluctuate, this difference spoils the energy resolution. The idea behind dual readout calorimetry is to build a calorimeter capable of determining the e.m. fraction for each shower, so as to compensate for the effect these fluctuations on the overall energy resolution. The method aims at optimizing the energy resolution for single hadrons and for jets
Towards jet reconstruction in a realistic dual readout total absorption calorimeter.
No full textCalorimeters implemented in future lepton colliders will inevitably suffer from leakage on account of space restrictions and will need to operate in strong magnetic fields. Both these circumstances will affect the reconstruction of jets and will give rise to the need for corrections. In dual readout calorimeters, these corrections are complicated by the need to deal with more than one signal. In this article we describe simulation studies of these corrections in a total absorption dual readout calorimeter
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
- …
