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- ID:
- ivo://CDS.VizieR/J/MNRAS/430/425
- Title:
- VLT LBG Redshift Survey. III.
- Short Name:
- J/MNRAS/430/425
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of 2135 galaxy redshifts from the VLT LBG Redshift Survey (VLRS), a spectroscopic survey of z~3 galaxies in wide fields centred on background quasi-stellar objects. We have used deep optical imaging to select galaxies via the Lyman-break technique. Spectroscopy of the Lyman-break galaxies (LBGs) was then made using the Very Large Telescope (VLT) Visible Multi-Object Spectrograph (VIMOS) instrument, giving a mean redshift of z=2.79. We analyse the clustering properties of the VLRS sample and also of the VLRS sample combined with the smaller area Keck-based survey of Steidel et al. (2003, Cat. J/ApJ/592/728).
- ID:
- ivo://CDS.VizieR/J/A+A/432/381
- Title:
- VLT spectroscopic survey of RX J0152.7-1357
- Short Name:
- J/A+A/432/381
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extensive spectroscopic survey of RX J0152.7-1357, one of the most massive distant clusters of galaxies known. Multi-object spectroscopy, carried out with FORS1 and FORS2 on the ESO Very Large Telescope (VLT), has allowed us to measure more than 200 redshifts in the cluster field and to confirm 102 galaxies as cluster members. The mean redshift of the cluster is z=0.837+/-0.001 and we estimate the velocity dispersion of the overall cluster galaxy distribution to be ~1600km/s.
- ID:
- ivo://CDS.VizieR/II/350
- Title:
- VLT Survey Telescope ATLAS
- Short Name:
- II/350
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VLT Survey Telescope ATLAS survey is an optical ugriz survey aiming to cover ~4700deg^2^ of the southern sky to similar depths as the Sloan Digital Sky Survey (SDSS). From reduced images and object catalogues provided by the Cambridge Astronomical Surveys Unit, we first find that the median seeing ranges from 0.8-arcsec FWHM (full width at half-maximum) in i to 1.0-arcsec in u, significantly better than the 1.2-1.5arcsec seeing for SDSS. The 5{sigma} mag limit for stellar sources is r_AB_=22.7 and in all bands these limits are at least as faint as SDSS. SDSS and ATLAS are more equivalent for galaxy photometry except in the z band where ATLAS has significantly higher throughput. We have improved the original ESO magnitude zero-points by comparing m<16 star magnitudes with the AAVSO Photometric All-Sky Survey in gri, also extrapolating into u and z, resulting in zero-points accurate to ~+/-0.02mag. We finally compare star and galaxy number counts in a 250deg^2^ area with SDSS and other count data and find good agreement. ATLAS data products can be retrieved from the ESO Science Archive, while support for survey science analyses is provided by the OmegaCAM Science Archive, operated by the Wide-Field Astronomy Unit in Edinburgh.
- 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.
- 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.
2137. 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.
- 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.
2139. 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.
- 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.