1,720,961 research outputs found
Pentaquark Search in Decays and LHCb Open Data Release
No full textThis PhD thesis reports results of the physics analysis focused on the search of pentaquarks in decays. Pentaquarks were first reported in 2015 by the LHCb collaboration in system. After collecting more data, further results followed in 2019 and 2022. Observation or non-observation of in system would help to deepen the understanding of these exotic states. The data collected by the LHCb detector at CERN in the years 2015-2018 from proton-proton collisions at center of mass energies of 13 TeV is analyzed. This data amounts to 5.7 of integrated luminosity. After reconstructing the missing momentum of the soft or a from the decay of a meson, the decay dynamics are studied and the search for the pentaquark states in the system is performed. No signal is observed and the upper limits on the fit fractions for each of the studied pentaquark states are established at 95% confidence level: The Extended Cone Closure method developed to reconstruct the missing momentum in a 3-body decay could be used for further analyses with missing neutrals. Part of this thesis is dedicated to reporting the work done in preparation for the first LHCb Open Data release. A subset of the LHCbdata from the years 2011 - 2012 were made publicly available. The data sets are described with and are available on CERN Open Data Portal. An involved automated workflow was established for data curation and documentation
FIRST LHCB OPEN DATA RELEASE AND ANALYSIS PRESERVATION TECHNIQUES
No full textLHCb collaboration is releasing research-quality data to the public for the very first time. A data sample amounting to 200TB has been obtained in 2011 and 2012 during the Run I of the Large Hadron Collider. The data is aquired by the LHCb detector by recording the information of proton collisions in the LHC. The data has undergone a preprocessing step where physics objects, such as the trajectories of charged particles, were reconstructed from the raw information delivered by the complex detector system. The data is filtered and classified according to 300 physical processes and decays. The data is made available in the same format as is used internally by the LHCb physicists and is accompanied by extensive metadata and documentation, as well as a Glossary explaining several hundred special terms used in the preprocessing. The data can be analyzed using dedicated LHCb software, which is open-source
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
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