1,721,089 research outputs found
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Neutral Pion-hadron Correlations in 200 GeV Au + Au Collisions
Full text linkIn a newly explored kinematic condition which is extremely hot and dense, the asymptotic freedom feature of Quantum Chromodynamics (QCD) predicts a deconfined phase of nuclear matter, known as quark-gluon plasma (QGP), where quarks and gluons can move freely like a perfect liquid. The QGP can be produced using the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory. During these collisions, high momentum partons are produced. These partons fragment into jets which are collimated sprays of particles. In the case that the QGP is formed, these hard partons lose energy when traversing the QGP. Therefore, the resulting jets are modified, which is observed as a angular broadening and modification of momentum distribution of jet particles. Hence, the study of jet modifications helps to understand the properties of the QGP. In this research, jets are studied using pi0-hadron azimuth correlations which use high momentum neutral pions as triggers to indicate the present of a jet. The azimuth correlations, known as jet functions, between the trigger pi0 and the charged hadrons are corrected for detector efficiency and underlying flow harmonics up to the fourth order. The jet functions are used to extract angular width and per trigger yields of the jets. This research found the angular broadening and enhancement of soft jet particles in Au+Au collisions at 200 GeV compared to p+p results, while hard jet particles are suppressed but no significant angular broadening is observed.
To be able to fully interpret the modification observed in heavy-ion collisions, a deeper understanding of the initial state of confined quarks in the nuclei is needed. Therefore, the next era of nuclear physics requires an Electron-Ion Collider (EIC) to construct the comprehensive nucleon tomography in different phase spaces. This dissertation details work performed to develop a compact aerogel ring-imaging Cherenkov detector called the mRICH with a focusing Fresnel lens to overcome the space limitation in the EIC detector
Measurements of Collectivity in the Forward Region at LHCb
No full textParticle flow measurements, which provide evidence of the QGP
medium, are a powerful tool to study the QGP evolution in heavy-ion
collisions. Using the two-particle correlation technique, the LHCb has observed
the ridge structure due to particle flow, in the forward pseudorapidity
range of 2 < η < 5 alongside the leading jet peak in long-range
correlations (|Δη| > 2). This paper will detail the analysis of the ridge
structure in pPb/Pbp collisions at 5 TeV and the results, which show that
the ridge structure is more pronounced in the low transverse momentum
region and the high-multiplicity events where the collective flow property
of QGP may be significant. This presentation will also include the details
of new LHCb analyses to extract the flow harmonics in the forward region
10th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions
No full textFlow results in small systems at RHIC and the LHC indicate QGP droplets are
formed in these collision systems. Measurements of jet on the other
hand are consistent with no modification to the jets produced. However,
non-zero values for high momentum particles, which in A+A collisions
are attributed to path-length dependent energy loss, have been observed in
small systems. To further probe possible modification to jet particles,
PHENIX measures the relative modification of the near and away-side jet
particles in pi0-hadron correlations in 200 GeV d+Au and 3He+Au collisions.
Modifications similar to the high suppression and low momentum
enhancement of associated particles observed in A+A collisions have been
observed in d+Au collisions. These surprising results have now also been
seen in 3He+Au data. These PHENIX measurements and possible interpretations
of these intriguing results will be presented
Exploring jet modification via gamma-hadron and pi0-hadron correlations in AuAu collisions at PHENIX
No full textTalk presented at the Winter Workshop on Nuclear Dynamics 2022 conferenc
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