1,723,133 research outputs found
Taylor, James, 6429
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/420503Surname: TAYLOR. Given Name(s) or Initials: JAMES. Military Service Number or Last Known Location: 6429. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 20309.245213
Item: [2016.0049.52764] "Taylor, James, 6429
First X-ray Observations of the Young Pulsar J1357-6429
Full text linkThe first short Chandra and XMM-Newton observations of the young and energetic pulsar J1357-6429 provided strong indications of a tail-like pulsar-wind nebula associated with this object, as well as strong pulsations of its X-ray flux with a pulsed fraction above 40% and a thermal component dominating at lower photon energies (below 2 keV). The elongated nebular is very compact in size. about 1" x 1.5" and might be interpreted as a pulsar jet. The thermal radiation is most plausibly emitted from the entire neutron star surface of an effective temperature about 1 MK covered with a magnetized hydrogen atmosphere At higher energies the pulsar's emission is of a nonthermal (magnetospheric) origin, with a power-law spectrum of a photon index Gamma approx. equals 1.1. This makes the X-ray properties of PSR J1357-6429 very similar to those of the youngest pulsars J1119-6127 and Vela with a detected thermal radiation
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
The circumstellar environment of the FS CMa star IRAS 00470+6429
No full textAbstractFS CMa type stars are a recently described group of objects with the B[e] phenomenon that exhibit strong emission-line spectra and strong IR excesses. In this paper we report the first attempt for a detailed modeling of IRAS 00470+6429, for which we have the best set of observations. Our modeling is based on two key assumptions: the star has a main-sequence luminosity for its spectral type (B2) and that the circumstellar (CS) envelope is bimodal, composed of a slowly outflowing disk-like wind and a fast polar wind. Both outflows are assumed to be purely radial. We adopt a novel approach to describe the dust formation site in the wind that employs timescale arguments for grain condensation and a self-consistent solution for the dust destruction surface. With the above assumptions we were able to reproduce satisfactorily many observational properties of IRAS 00470+6429, including the HI line profiles and the overall shape of the spectral energy distribution.</jats:p
VLT observations of the two<i>Fermi</i>pulsars PSR J1357−6429 and PSR J1048−5832
No full textContext. Optical observations of pulsars are crucial to studying the
neutron star properties from the structure and composition of the interior to the
properties and geometry of the magnetosphere. Historically, X and γ-ray
observations have paved the way to pulsar optical identifications. The launch of the
Fermi Gamma-ray Space Telescope opened new perspectives in the
optical-to-γ-ray studies of neutron stars with the detection of more
than 80 γ-ray pulsars.
Aims. Here, we aim to search for optical emission from two
Fermi pulsars that are interesting targets on the basis of their
spin-down age, energetics, and distance. PSR J1357−6429 is a Vela-like pulsar
(P = 166.1 ms; τ = 7.31 kyr), at a distance of ~2.4
kpc with a rotational energy loss rate Ė ~ 3 × 1036 erg
s-1. PSR J1048−5832 is also a Vela-like (P = 123.6 ms;
τ = 20.3 kyr) pulsar at a distance of ~2.7 kpc and with a
Ė ~ 2 × 1036 erg s-1. The two pulsars and their
pulsar wind nebulae (PWNe) are also detected in X-rays by Chandra and
XMM-Newton. No deep optical observations of these two pulsars have been
reported so far.
Methods. We used multi-band optical images (V,R,I)
taken with the Very Large Telescope (VLT) and available in the European Southern
Observatory (ESO) archive to search for, or put tight constraints on, their optical
emission.
Results. We re-assessed the positions of the two pulsars from the
analyses of all the available Chandra observations and the comparison
with the published radio coordinates. For PSR J1357−6429, this yielded a tentative
proper motion \hbox{\mu = 0\farcs17
\pm 0\farcs055}
yr-1 (70° ± 15° position angle). We did not detect any
candidate counterparts to PSR J1357−6429 and PSR J1048−5832 down to
V ~ 27 and ~27.6, respectively, although for the former we found
possible evidence of a faint, unresolved object at the Chandra position.
Our limits imply an efficiency in converting spin-down power into optical luminosity
≲7 × 10-7 and ≲ 6 × 10-6, possibly close to that of the Vela
pulsar.
Conclusions. Observations with the Hubble Space
Telescope (HST) are required to identify PSR J1357−6429 against nearby field stars.
Owing to the high extinction (AV ~ 5) and the
presence of a molecular cloud complex, near-infrared observations of PSR J1048−5832 are
better suited to spotting its candidate counterpart
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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