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2061. VLT/VIMOS spectroscopy in GOODS-South field
ID:
ivo://CDS.VizieR/J/A+A/512/A12
Title:
VLT/VIMOS spectroscopy in GOODS-South field
Short Name:
J/A+A/512/A12
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the full data set of the VIsible Multi-Object Spectrograph (VIMOS) spectroscopic campaign of the ESO/GOODS program in the Chandra Deep Field South (CDFS), which complements the FORS2 ESO/GOODS spectroscopic campaign. The ESO/GOODS spectroscopic programs are aimed at reaching signal-to-noise ratios adequate to measure redshifts for galaxies with AB magnitudes in the range ~24-25 in the B and R band using VIMOS, and in the z band using FORS2.
2062. VMC XXVII. Young stellar structures in the LMC
ID:
ivo://CDS.VizieR/J/ApJ/849/149
Title:
VMC XXVII. Young stellar structures in the LMC
Short Name:
J/ApJ/849/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
Star formation is a hierarchical process, forming young stellar structures of star clusters, associations, and complexes over a wide range of scales. The star-forming complex in the bar region of the Large Magellanic Cloud is investigated with upper main-sequence stars observed by the VISTA Survey of the Magellanic Clouds. The upper main-sequence stars exhibit highly nonuniform distributions. Young stellar structures inside the complex are identified from the stellar density map as density enhancements of different significance levels. We find that these structures are hierarchically organized such that larger, lower-density structures contain one or several smaller, higher- density ones. They follow power-law size and mass distributions, as well as a lognormal surface density distribution. All these results support a scenario of hierarchical star formation regulated by turbulence. The temporal evolution of young stellar structures is explored by using subsamples of upper main-sequence stars with different magnitude and age ranges. While the youngest subsample, with a median age of log({tau}/yr)=7.2, contains the most substructure, progressively older ones are less and less substructured. The oldest subsample, with a median age of log({tau}/yr)=8.0, is almost indistinguishable from a uniform distribution on spatial scales of 30-300pc, suggesting that the young stellar structures are completely dispersed on a timescale of ~100Myr. These results are consistent with the characteristics of the 30 Doradus complex and the entire Large Magellanic Cloud, suggesting no significant environmental effects. We further point out that the fractal dimension may be method dependent for stellar samples with significant age spreads.
2063. VPHAS+ DR2 survey
ID:
ivo://CDS.VizieR/II/341
Title:
VPHAS+ DR2 survey
Short Name:
II/341
Date:
21 Oct 2021
Publisher:
CDS
Description:
The primary goal of the VST Photometric H{alpha} Survey of the Southern Galactic Plane and Bulge (VPHAS+) is to collect single-epoch ugri broad-band and Ha narrow-band photometry across the southern Galactic Plane within the latitude range -5{deg}<b<+5{deg} down to point source magnitudes of ~21 or better. The VPHAS+ footprint also includes the inner Galactic Bulge, defined as a 20x20 deg^2^ box around the Galactic Centre: this assures optical coverage of the full VVV footprint. For all massive OBA stars this survey is deep enough to explore all but the most heavily obscured locations of the southern Plane, reaching to >4kpc from the Sun. These data will increase the number of known southern emission line stars by up to an order of magnitude, yielding much better statistics on important short-lived types of object. The wide-area uniform photometry obtained will also facilitate stellar population studies, capable of tracing structure over much of the southern Plane. VPHAS+ will trawl the star-formation history of the Galaxy as seen in stellar remnants of all types.
2064. VRI photometry of PDCS survey
ID:
ivo://CDS.VizieR/J/AJ/120/1
Title:
VRI photometry of PDCS survey
Short Name:
J/AJ/120/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents the COP (CFHT optical PDCS; CFHT: Canada-France-Hawaii Telescope, PDCS: Palomar Distant Cluster Survey) survey data. We describe our photometric and spectroscopic observations with the multiobject spectrograph (MOS) at the CFHT. A comparison of the photometry from the PDCS catalogs and from the new images we have obtained at the CFHT shows that the different magnitude systems can be cross-calibrated. After identification between the PDCS catalogs and our new images, we built catalogs with redshift, coordinates, and V_PDCS_, I_PDCS_, and R_COP_ magnitudes. We have classified the galaxies along the lines of sight into field and structure galaxies using a gap technique from Katgert et al. In total we have observed 18 significant structures along the 10 lines of sight.
2065. VSOP 5 GHz AGN Survey
ID:
ivo://CDS.VizieR/J/PASJ/52/997
Title:
VSOP 5 GHz AGN Survey
Short Name:
J/PASJ/52/997
Date:
21 Oct 2021
Publisher:
CDS
Description:
The VSOP mission is a Japanese-led project to image radio sources with sub-milliarcsec resolution by correlating the signal from the orbiting 8-m telescope, HALCA, with a global array of telescopes. Twenty- five percent of the scientific time of this mission is devoted to a survey of 402 bright, small-diameter extra-galactic radio sources at 5-GHz. The major goals of the VSOP Survey are statistical in nature: to determine the brightness temperature and approximate structure; to provide a source list for use with future space VLBI missions; and to compare radio properties with other data throughout the EM spectrum. This paper describes: the compilation of a complete list of radio sources associated with active galactic nuclei (AGN); the selection of the subsample of sources to be observed with VSOP; the extensive ground resources used for the Survey; the status of the observations as of 2000 July; the data-analysis methods; and several examples of results from the VSOP Survey. More detailed results from the full sample will be given in future papers.
2066. VSOP 5 GHz AGN Survey. III
ID:
ivo://CDS.VizieR/J/ApJS/155/33
Title:
VSOP 5 GHz AGN Survey. III
Short Name:
J/ApJS/155/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
The VLBI Space Observatory Programme (VSOP) mission is a Japanese-led project to study radio sources with sub-milliarcsec resolution using an orbiting 8m telescope, HALCA, along with global arrays of Earth-based telescopes. Approximately 25% of the observing time is devoted to a survey of compact active galactic nuclei (AGNs) that are stronger than 1Jy at 5GHz - the VSOP AGN Survey. This paper, the third in the series, presents the results from the analysis of the first 102 Survey sources.
2067. VSOP 5GHz AGN Survey. IV
ID:
ivo://CDS.VizieR/J/ApJ/616/110
Title:
VSOP 5GHz AGN Survey. IV
Short Name:
J/ApJ/616/110
Date:
21 Oct 2021
Publisher:
CDS
Description:
The VLBI Space Observatory Programme (VSOP) mission is a Japanese-led project to study radio sources with submilliarcsecond angular resolution, using an orbiting 8m telescope on board the satellite HALCA with a global Earth-based array of telescopes. A major program is the 5GHz VSOP Survey Program, which we supplement here with Very Long Baseline Array observations to produce a complete and flux density-limited sample. Using statistical methods of analysis of the observed visibility amplitude versus projected (u, v) spacing, we have determined the angular size and brightness temperature distribution of bright radio emission from active galactic nuclei.
2068. VSOP 5GHz AGN survey V.
ID:
ivo://CDS.VizieR/J/ApJS/175/314
Title:
VSOP 5GHz AGN survey V.
Short Name:
J/ApJS/175/314
Date:
21 Oct 2021
Publisher:
CDS
Description:
In 1997 February, the Japanese radio astronomy satellite HALCA was launched to provide the space-bourne element for the VLBI Space Observatory Program (VSOP) mission. Approximately 25% of the mission time was dedicated to the VSOP survey of bright compact active galactic nuclei (AGNs) at 5GHz. This paper, the fifth in the series, presents images and models for the remaining 140 sources not included in the third paper in the series, which contained 102 sources. For most sources, the plots of the (u,v) coverage, the visibility amplitude versus (u,v) distance, and the high-resolution image are presented. Model fit parameters to the major radio components are determined, and the brightness temperature of the core component for each source is calculated. The brightness temperature distributions for all of the sources in the VSOP AGN survey are discussed.
2069. VSOP 5 GHz continuum survey
ID:
ivo://CDS.VizieR/J/ApJS/131/95
Title:
VSOP 5 GHz continuum survey
Short Name:
J/ApJS/131/95
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have imaged with milliarcsecond resolution at 5 GHz 374 strong flat-spectrum radio sources north of declination -44{deg} using the VLBA in 1996 June. The source sample was compiled from the source list for the VLBI Space Observatory Programme (VSOP) Survey Program. About 250 of the sources observed with the VLBA had correlated flux densities >=0.3 Jy on the longest VLBA baseline and these sources are currently being observed with VSOP at 5 GHz. This paper presents the results from the VLBA prelaunch observations: the correlated flux density dependence with u-v distance; the contour display of the images; the model fit parameters for each radio component; and improved positions for 62 sources. Comparisons and extensive cross-referencing with other major VLBI surveys are also given.
2070. VST ATLAS white dwarf candidates cat.
ID:
ivo://CDS.VizieR/J/MNRAS/469/621
Title:
VST ATLAS white dwarf candidates cat.
Short Name:
J/MNRAS/469/621
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Sloan Digital Sky Survey (SDSS) has created a knowledge gap between the Northern and the Southern hemispheres, which is very marked for white dwarfs: Only ~15 per cent of the known white dwarfs are south of the equator. Here, we make use of the VLT Survey Telescope (VST) ATLAS survey, one of the first surveys obtaining deep, optical, multiband photometry over a large area of the southern skies, to remedy this situation. Applying the colour and proper-motion selection developed in our previous work on SDSS to the most recent internal data release (2016 April 25) of VST ATLAS, we created a catalogue of ~4200 moderately bright (g<=19), high-confidence southern white dwarf candidates, which can be followed up individually with both the large array of southern telescopes or in bulk with ESO's forthcoming multi-object spectrograph 4MOST.