1,724,331 research outputs found
Electromagnetic multipole moments of the P-c(+) (4380) pentaquark in light-cone QCD
No full textAzizi, Kazem (Dogus Author)We calculate the electromagnetic multipole moments of the P-c(+) (4380) pentaquark by modeling it as the diquark-diquark-antiquark and D-* Sigma(c) molecular state with quantum numbers J(P) = 3/2(-). In particular, the magnetic dipole, electric quadrupole and magnetic octupole moments of this particle are extracted in the framework of light-cone QCD sum rule. The values of the electromagnetic multipole moments obtained via two pictures differ substantially from each other, which can be used to pin down the underlying structure of P-c(+) (4380). The comparison of any future experimental data on the electromagnetic multipole moments of the P-c(+) (4380) pentaquarkwith the results of the presentwork can shed light on the nature and inner quark organization of this state
Block Card 4380 Rugby Drive
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: Cape Cod Style | Dwelling | Copland Woods Addition (Toledo, Ohio) | South Toledo Area (Toledo, Ohio) | 4380 Rugby Drive (Toledo, Ohio
Heavy pentaquark states Pc(4380) and Pc(4450) in the J/ψ production induced by pion beams off the nucleon
No full textAbstractIn this study, we investigate the J/ψ production induced by pion beams off the nucleon, particularly the heavy pentaquarks Pc(4380) and Pc(4450) in intermediate states, based on a hybridized Regge model. The process involving ρ and π meson exchange in the t channel is considered as background, and the heavy pentaquark exchange is included in the s channel. The coupling constants such as the ρNN and πNN vertices are taken from the NN potentials, whereas those for the J/ψρπ and J/ψππ vertices are determined by using experimental data based on the branching ratios. In order to estimate the Pc(4380) and Pc(4450) coupling constants, we use the experimental upper limit on the total cross section as a guide for the πN→J/ψN reaction. The background total cross section is the order of 10−4–10−3 nb. In the vicinity of the heavy pentaquark masses, the total cross section reaches about 1 nb
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
No full textWe 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
Strong decay of P-c (4380) pentaquark in a molecular picture
No full textAzizi, Kazem (Dogus Author)There are different assumptions on the substructure of the pentaquarks P-c(4380) and P-c(4450), newly founded in J/psi N invariant mass by the LHCb Collaboration, giving consistent mass results with the experimental observations. The experimental data and recent theoretical studies on their mass suggest interpretation of these states as spin-3/2 negative-parity and spin-5/2 positive-parity pentaquarks, respectively. There may exist opposite-parity states corresponding to these particles, as well. Despite a lot of studies, however, the nature and internal organization of these pentaquarks in terms of quarks and gluons are not clear. To this end we need more theoretical investigations on other physical properties of these states. In this accordance, we study a strong and dominant decay of the P-c(4380) to J/psi and N in the framework of three point QCD sum rule method. An interpolating current in a molecular form is applied to calculate six strong coupling form factors defining the transitions of the positive and negative parity spin-3/2 pentaquark states. The values of the coupling constants are used in the calculation of the decay widths of these transitions. The obtained results are compared with the existing experimental data
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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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