208 research outputs found
KiDS0239-3211: A new gravitational quadruple lens candidate
We report the discovery of a candidate to quadrupole gravitationally lensed
system KiDS0239-3211 based on the public data release 3 of the KiDS survey and
machine learning techniques
A Revised Checklist of Mongolian Mammal Species
A revised annotated checklist of Mongolian mammals is presented, supplemented with comments on modifications in species- and genus-level taxonomy introduced over the last 30 years. The checklist includes 140 species compared to 124 species recognized three decades ago by SOKOLOV & ORLOV (1980). Since then, four species were newly described; seven species were registered for the first time on Mongolian territory. Names for more than 20 taxa have changed, on most occasions this change occurred not for purely nomenclatural reasons but rather as a result of taxonomic revisions at the species level which have elevated the rank of many nominal taxa treated previously as subspecies. Recent molecular studies have shown that many widespread Central Asian species, in fact, consist of several highly divergent phylogenetic lineages the taxonomic status of which is yet unclear. Therefore, further updates to our knowledge of mammal biodiversity in Mongolia are expected
A Dipole Vortex Model of Obscuring Tori in Active Galaxy Nuclei
The torus concept as an essential structural component of active galactic
nuclei (AGN) is generally accepted. Here, the situation is discussed when the
torus "twisting" by the radiation or wind transforms it into a dipole toroidal
vortex which in turn can be a source of matter replenishing the accretion disk.
Thus emerging instability which can be responsible for quasar radiation flares
accompanied by matter outbursts is also discussed. The "Matreshka" scheme for
an obscuring vortex torus structure capable of explaining the AGN variability
and evolution is proposed. The model parameters estimated numerically for the
luminosity close to the Eddington limit agree well with the observations.Comment: 17 pages, 11 figures, version of this paper is published in Astronomy
Report
Self-education as a factor of sustainable professional growth specialist
The article is devoted to the problem of self-education of specialist in organization of new information. Information society is characterized as a knowledge society, where the key ones are access to information, ability to work with it and transform it into knowledge. Presents the recommendations for improving the effectiveness of the process of self-education for specialists and management of the organizations interested in the formation of highly qualified personnelРассматривается проблема самообразования специалистов организации в новых информационных условиях. Представлены рекомендации по повышению эффективности процесса самообразования для специалистов и руководства организаций, заинтересованного в формировании высококвалифицированного персонал
Trade Services System Adaptation for Sustainable DevelopmentTrade Services System Adaptation for Sustainable Development
KiDS-SQuaD: The KiDS Strongly lensed Quasar Detection project
New methods have been recently developed to search for strong gravitational
lenses, in particular lensed quasars, in wide-field imaging surveys. Here, we
compare the performance of three different, morphology- and photometry- based
methods to find lens candidates over the Kilo-Degree Survey (KiDS) DR3
footprint (440 deg). The three methods are: i) a multiplet detection in
KiDS-DR3 and/or Gaia-DR1, ii) direct modeling of KiDS cutouts and iii)
positional offsets between different surveys (KiDS-vs-Gaia, Gaia-vs-2MASS),
with purpose-built astrometric recalibrations. The first benchmark for the
methods has been set by the recovery of known lenses. We are able to recover
seven out of ten known lenses and pairs of quasars observed in the KiDS DR3
footprint, or eight out of ten with improved selection criteria and looser
colour pre-selection. This success rate reflects the combination of all methods
together, which, taken individually, performed significantly worse (four lenses
each). One movelty of our analysis is that the comparison of the performances
of the different methods has revealed the pros and cons of the approaches and,
most of all, the complementarities. We finally provide a list of high-grade
candidates found by one or more methods, awaiting spectroscopic follow-up for
confirmation. Of these, KiDS 1042+0023 is to our knowledge the first confirmed
lensed quasar from KiDS, exhibiting two quasar spectra at the same source
redshift at either sides of a red galaxy, with uniform flux-ratio
over the wavelength range
Comment: 12 pages, 4 figures, 4 tables, accepted for publication in MNRA
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