1,720,987 research outputs found
Studies of the W±W± scattering process in pp collisions at the once and future ATLAS detector
Get PDFImplementation and Setup of a System Dedicated Logbook based on ELisA
No full textELisA is a web tool used by the ATLAS community as a daily logbook facility in order to record and share information concerning the experiment's operation and deployment. A few subsystems, notably the FTK subsystem, of the ATLAS experiment would like to setup a logbook based on the ELisA logbook for their own private usage. This new logbook would be completely separated from the main ATLAS logbook and will only be accessed from the general public network. In this project the implementation and setup of the ELisA based logbook will be discussed as well as various modifications that were made to the new logbook. These modifications were specified by the FTK users in order to make the logbook relevant to the FTK subsystem. Once the logbook was functioning as expected and the users were satisfied with the modifications, the FTK logbook was installed on a FTK dedicated machine where it is currently being used by members of the FTK group
Measurements of <em>q</em><sup>2</sup> moments of inclusive <em>B</em> → <em>X<sub>c</sub></em>ℓν decays toward an alternative determination of |<em>V<sub>cb</sub></em>|
No full textThis thesis presents the first measurement of the first to the fourth moments of the four-momentum transfer squared q2 spectrum for inclusive B → Xcℓν decays, where ℓ = e, μ. The determination of these moments and their systematic uncertainties are crucial experimental inputs for a novel, alternative method to determine the magnitude of the CKM matrix element Vcb using a reduced set of hadronic matrix elements in the heavy quark expansion. The analysis investigates the complete ϒ(4S) data set collected by the Belle detector, corresponding to 711 fb-1 of integrated luminosity and a total of (772 ± 10) × 106 B meson pairs. To identify and reconstruct the kinematic variables of inclusive semileptonic B meson decays, machine learning techniques are employed to fully reconstruct one of the B mesons in purely hadronic decay modes. Consequently, this approach allows for the kinematics of the remaining B meson to be inferred using conservation laws leading to the explicit reconstruction of the hadronic Xc system and, in turn, the q2 spectrum. The moments are measured with progressively increasing threshold selections on q2: from q2 > 3.0 GeV2 to q2 > 10.0 GeV2 while incrementing the threshold in 0.5 GeV2 steps. To ensure an unbiased result, the measured moments are unfolded and corrected for reconstruction and selection effects. The measured moments are reported separately for electron and muon final states, allowing for a test of lepton flavour universality. No deviation from the expectation of unity is observed. In addition, the presented measurement is combined with theoretical predictions of the ⟨qn⟩ moments and the semileptonic decay rate up to order 1/mb4 to perform a simultaneous fit and extract |Vcb| in a data-driven manner. A value of |Vcb| × 103 = 41.7 ± 1.2 is obtained, which is consistent with previous determinations within experimental uncertainty
First extraction of inclusive V-cb from q(2) moments
Get PDFWe present the first determination of V cb from inclusive B→ X cℓ v¯ ℓ using moments of the dilepton invariant mass, q 2. These moments are reparametrization invariant quantities and depend on a reduced set of non-perturbative parameters. This reduced set of parameters opens a new path to extract these parameters up to 1/mb4 purely from data and can potentially reduce the uncertainty on V cb. In this paper, we present our first determination of V cb using this method. Combining the recent measurements of q 2 moments by Belle and Belle II, our default fit gives |V cb| = (41.69±0.63)·10 −3. This result presents an important independent cross check of, and is consistent with, the previous state-of-the-art inclusive determinations using lepton energy and hadronic invariant mass moments
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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