1,720,961 research outputs found
Search for long-lived particles in events with a displaced vertex using the ATLAS detector with the full Run2 dataset
No full textA large number of physics models that extend the Standard Model predict the existence of new, massive, long-lived particles. Searches for these processes may target its decay products at a significant distance from the collision point. This signature provides interesting technical challenges due to their special reconstruction requirements as well as their unusual backgrounds. This poster will present recent results in long-lived SUSY searches using a displaced vertex in the Inner Detector in association to jets with the ATLAS full Run 2 data
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
Search for long-lived supersymmetric particles using displaced vertices and multiple jets in collisions at = 13 TeV with the ATLAS detector
No full textThe Standard Model (SM) of particle physics describes all fundamental forces of electromagnetic, weak, and strong interactions, except for gravity in the universe. The behaviour of elementary particles predicted by the SM is in good agreement with the results of the experiments obtained so far. However, there are some problems that cannot be solved by the SM alone; the Higgs boson mass 125 GeV cannot be naturally derived and the dark matter cannot be formed from the particles in the SM. Supersymmetry (SUSY) could solve these problems. Also, SUSY possibly unifies the electroweak and strong interactions at a high energy scale. SUSY particles have been searched for up to TeV at the Large Hadron Collider (LHC), but no SUSY particles have been found. A large parameter space for SUSY particles, which provides all above benefits, has been excluded. Therefore, I focused on the SUSY model, which solves the mass problem of the Higgs boson at least. I focused on the -parity violating model. In this model, the lightest SUSY particles can decay to the SM particles. The coupling constants between SM and SUSY particles are predicted to be small due to proton decay constraints. Since regions with very small coupling constant have already been searched for in other analyses at the ATLAS experiment, this thesis focuses on the case where the coupling constant is -. This case does not allow SUSY particles to form dark matter candidates, but the other two benefits can be kept. This thesis presents a search for long-lived SUSY particles in events with displaced vertices and multiple jets using the 139 of collision data collected at = 13 TeV by the ATLAS detector at the LHC. Two signal processes are searched for, which are , and . The lightest electrowikinos have a long lifetime due to the small -parity violating coupling. I focus on the models characterized by multiple jets and the decay vertex of the long-lived electrowikino being - mm away from the interaction point, which is called displaced vertex. We established the analysis method using dedicated techniques to reconstruct the tracks derived from the long-lived electrowikino decay and the decay vertex of the electrowikino. A signal region (SR) is defined for each signal process. In SRs, at least one displaced vertex and multiple high momentum jets are required. The displaced vertex must be reconstructed from five or more tracks and the invariant mass calculated from the four-momenta of these tracks, obtained by assuming the pion mass for each track, must be larger than 10 GeV. The dominant background events are due to accidental reconstruction of displaced vertices by some sources. I established a new background estimation method and achieved accurate estimation. The new method estimates the background events inclusively using the relation between the number of accidentally reconstructed displaced vertices and the number of jets. The number of observed events did not significantly exceed the background estimations in each SR. At 95% confidence level, the neutralino mass up to 1.58 TeV for lifetime of 0.1 ns is excluded. This analysis allows the search for the models in which the lightest electrowikino with lifetimes of 0.01 - 1 ns decays into light-flavour quarks, which has not been searched for to date
Search for long-lived particles in events with a displaced vertex using the ATLAS detector with the full Run 2 dataset
No full textA large number of physics models beyond the Standard Model predict the existence of new, massive, long-lived particles. Searches for these particles rely on the detection of the decay products at a significant distance from the collision point. This signature provides interesting technical challenges due to their special reconstruction requirements as well as their unusual backgrounds. Recent results in the search for long-lived SUSY particles using a displaced vertex in the Inner Detector in association with jets with the ATLAS full Run 2 data are presented
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
