- ID:
- ivo://CDS.VizieR/J/A+A/585/A49
- Title:
- VCNS II. The IR-excess-selected population
- Short Name:
- J/A+A/585/A49
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a deep wide-field (6.76 square-degrees) near-infrared survey with the VISTA telescope that covers the entire extent of the Carina nebula complex. Complementing the VISTA near-infrared catalog with Spitzer IRAC mid-infrared photometry improves the situation of the background contamination considerably. We find that a (J-H) versus (Ks-[4.5]) color-color diagram is well suited to tracing the population of YSO-candidates (cYSOs) by their infrared excess. We identify 8781 sources with strong infrared excess, which we consider as cYSOs. This sample is used to investigate the spatial distribution of the cYSOs with a nearest-neighbor analysis. The surface density distribution of cYSOs agrees well with the shape of the clouds as seen in our Herschel far-infrared survey. The strong decline in the surface density of excess sources outside the area of the clouds supports the hypothesis that our excess-selected sample consists predominantly of cYSOs with a low level of background contamination.
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- ID:
- ivo://CDS.VizieR/J/A+A/581/A10
- Title:
- VEGAS: A VST Early-type GAlaxy Survey
- Short Name:
- J/A+A/581/A10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the VST Early-type GAlaxy Survey (VEGAS), which is designed to obtain deep multiband photometry in g, r, i, of about one hundred nearby galaxies down to 27.3, 26.8, and 26mag/arcsec^2^ respectively, using the ESO facility VST/OmegaCAM. The goals of the survey are 1) to map the light distribution up to ten effective radii, r_e_; 2) to trace color gradients and surface brightness fluctuation gradients out to a few r_e_ for stellar population characterization; and 3) to obtain a full census of the satellite systems (globular clusters and dwarf galaxies) out to 20% of the galaxy virial radius. The external regions of galaxies retain signatures of the formation and evolution mechanisms that shaped them, and the study of nearby objects enables a detailed analysis of their morphology and interaction features. To clarify the complex variety of formation mechanisms of early-type galaxies (ETGs), wide and deep photometry is the primary observational step, which at the moment has been pursued with only a few dedicated programs. The VEGAS survey has been designated to provide these data for a volume-limited sample with exceptional image quality. In this commissioning photometric paper we illustrate the capabilities of the survey using g- and i-band VST/OmegaCAM images of the nearby galaxy NGC 4472 and of smaller ETGs in the surrounding field. Our surface brightness profiles reach rather faint levels and agree excellently well with previous literature. Genuine new results concern the detection of an intracluster light tail in NGC 4472 and of various substructures at increasing scales. We have also produced extended (g-i) color profiles. The VST/OmegaCAM data that we acquire in the context of the VEGAS survey provide a detailed view of substructures in the optical emission from extended galaxies, which can be as faint as a hundred times below the sky level.
- ID:
- ivo://CDS.VizieR/J/ApJS/213/34
- Title:
- Velocities of Cygnus OB2 massive binaries
- Short Name:
- J/ApJS/213/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze orbital solutions for 48 massive multiple-star systems in the Cygnus OB2 association, 23 of which are newly presented here, to find that the observed distribution of orbital periods is approximately uniform in log P for P<45days, but it is not scale-free. Inflections in the cumulative distribution near 6days, 14days, and 45days suggest key physical scales of =~0.2, =~0.4, and =~1A.U. where yet-to-be-identified phenomena create distinct features. No single power law provides a statistically compelling prescription, but if features are ignored, a power law with exponent {beta}=~-0.22 provides a crude approximation over P=1.4-2000days, as does a piece-wise linear function with a break near 45days. The cumulative period distribution flattens at P>45days, even after correction for completeness, indicating either a lower binary fraction or a shift toward low-mass companions. A high degree of similarity (91% likelihood) between the Cyg OB2 period distribution and that of other surveys suggests that the binary properties at P<~25days are determined by local physics of disk/clump fragmentation and are relatively insensitive to environmental and evolutionary factors. Fully 30% of the unbiased parent sample is a binary with period P<45days. Completeness corrections imply a binary fraction near 55% for P<5000days. The observed distribution of mass ratios 0.2<q<1 is consistent with uniform, while the observed distribution of eccentricities 0.1<e<0.6 is consistent with uniform plus an excess of e=~0 systems. We identify six stars, all supergiants, that exhibit aperiodic velocity variations of ~30km/s attributed to atmospheric fluctuations.
- ID:
- ivo://CDS.VizieR/J/AJ/133/2487
- Title:
- VERA 22GHz Fringe Search Survey
- Short Name:
- J/AJ/133/2487
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents results of a survey search for bright compact radio sources at 22GHz with the VERA radio interferometer. Each source from a list of 2494 objects was observed in one scan for 2 minutes. The purpose of this survey was to find compact extragalactic sources bright enough at 22GHz to be useful as phase calibrators. Observed sources were either (1) within 6{deg} of the Galactic plane, or (2) within 11{deg} of the Galactic center, or (3) within 2{deg} of known water masers. Among the observed sources, 549 were detected, including 180 extragalactic objects that were not previously observed with the very long baseline interferometry technique. Estimates of the correlated flux densities of the detected sources are presented. It was found that the probability of detecting a 200mJy source with 120s of integration time is 60%.
- ID:
- ivo://CDS.VizieR/J/MNRAS/360/340
- Title:
- Very Small Array. Flux density at 33GHz
- Short Name:
- J/MNRAS/360/340
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the source subtraction strategy and observations for the extended Very Small Array (VSA), a cosmic microwave background interferometer operating at 33GHz. A total of 453 sources were monitored at 33GHz using a dedicated source subtraction baseline. 131 sources brighter than 20mJy were directly subtracted from the VSA visibility data. Some characteristics of the subtracted sources, such as spectra and variability, are discussed. The 33GHz source counts are estimated from a sample selected at 15GHz. The selection of VSA fields in order to avoid bright sources introduces a bias into the observed counts. This bias is corrected and the resulting source count is estimated to be complete in the flux-density range 20114mJy. The 33GHz source counts are used to calculate a correction to the VSA power spectrum for sources below the subtraction limit.
2016. VEXAS DR2 catalogs
- ID:
- ivo://CDS.VizieR/II/369
- Title:
- VEXAS DR2 catalogs
- Short Name:
- II/369
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present the second public data release of the VISTA EXtension to Auxiliary Surveys (VEXAS DR2), where we classify objects into stars, galaxies and quasars based on an ensemble of machine learning algorithms. The aim of VEXAS is to build the widest multi-wavelength catalogue, providing reference magnitudes, colours and morphological information for a large number of scientific uses. We apply an ensemble of thirty-two different machine learning models, based on three different algorithms and on different magnitude sets, training samples and classification problems (two or three classes) on the three VEXAS Data Release 1 (DR1) optical+infrared (IR) tables. The tables were created in DR1 cross-matching VISTA near-infrared data with Wide-field Infrared Survey Explorer far-infrared data and with optical magnitudes from the Dark Energy Survey (VEXAS-DESW), the Sky Mapper Survey (VEXAS-SMW), and the Panoramic Survey Telescope and Rapid Response System Survey (VEXAS-PSW). We assemble a large table of spectroscopically confirmed objects (VEXAS-SPEC-GOOD, 415 628 unique objects), based on the combination of six different spectroscopic surveys that we use for training. We develop feature imputation to classify also objects for which magnitudes in one or more bands are missing. We classify in total 90106 objects in the Southern Hemisphere. Among these, ~62.9x10^6^ (~52.6x10^6^) are classified as 'high confidence' ('secure') stars, ~920000 (~750000) as 'high confidence' ('secure') quasars and ~34.8 (~34.1) millions as 'high confidence' ('secure') galaxies, with pclass>=0.7 (pclass>=0.9). The DR2 tables update the DR1 with the addition of imputed magnitudes and membership probabilities to each of the three classes. The density of high-confidence extragalactic objects varies strongly with the survey depth: at pclass>0.7; there are 111/deg^2^ quasars in the VEXAS-DESW footprint and 103/deg^2^ in the VEXAS-PSW footprint, while only 10.7/deg^2^ in the VEXASSM footprint. Improved depth in the midIR and coverage in the optical and nearIR are needed for the SM footprint that is not already covered by DESW and PSW.
- ID:
- ivo://CDS.VizieR/J/MNRAS/383/1588
- Title:
- VIc photometry of NGC 2547 low-mass stars
- Short Name:
- J/MNRAS/383/1588
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on the results of an I-band time-series photometric survey of NGC 2547 using the MPG/ESO 2.2-m telescope with Wide Field Imager, achieving better than 1 per cent photometric precision per data point over 14~<I~<18. Candidate cluster members were selected from a V versus V-I colour-magnitude diagram over 12.5<V<24 (covering masses from 0.9M_{sun}_ down to below the brown dwarf limit), finding 800 candidates, of which we expect ~330 to be real cluster members, taking into account contamination from the field (which is most severe at the extremes of our mass range). Searching for periodic variations in these gave 176 detections over the mass range 0.1~<M/M_{sun}_<0.9.
- ID:
- ivo://CDS.VizieR/II/329
- Title:
- VIKING catalogue data release 1
- Short Name:
- II/329
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VIKING survey with VISTA (ESO programme ID 179.A-2004) is a wide area (eventually 1500 sq.degrees), intermediate-depth (5-sigma detection limit J=21 on Vega system) near-infrared imaging survey, in the five broadband filters Z, Y, J, H, Ks. The planned sky coverage is at high galactic latitudes, and includes two main stripes 70x10{deg}^2^ each: one in the South Galactic cap near Dec~-30{deg}, and one near Dec~0{deg} in the North galactic cap; in addition, there are two smaller outrigger patches called GAMA09 and CFHLS-W1. Science goals include z>6.5 quasars, extreme brown dwarfs, and multiwavelength coverage and identifications for a range of other imaging surveys, notably VST-KIDS and Herschel-ATLAS. This first public data release of data taken between the 12th of November 2009 and the 13th of February 2011 includes 151 tiles with complete coverage in all five VIKING filters (55 in GAMA09/12/14, 91 in SGP and 5 in CFHLS-W1) i.e. 226 square degrees, and includes approximately 14,773,385 total sources (including low-reliability single-band detections) and the imaging and source lists total 314.4GB. The coverage in each of the five sub-areas is not completely contiguous but any inter-tile gaps are relatively small. More details can be found in the accompanying documentation: viking_cat_dr1.pdf
- ID:
- ivo://CDS.VizieR/II/343
- Title:
- VIKING catalogue data release 2
- Short Name:
- II/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The VIKING survey with VISTA (ESO programme ID 179.A-2004) is a wide area (eventually 1500 sq.degrees), intermediate-depth (5-sigma detection limit J=21 on Vega system) near-infrared imaging survey, in the five broadband filters Z, Y, J, H, Ks. The planned sky coverage is at high galactic latitudes, and includes two main stripes 70x10{deg}^2^ each: one in the South Galactic cap near Dec~-30{deg}, and one near Dec~0{deg} in the North galactic cap; in addition, there are two smaller outrigger patches called GAMA09 and CFHLS-W1. Science goals include z>6.5 quasars, extreme brown dwarfs, and multiwavelength coverage and identifications for a range of other imaging surveys, notably VST-KIDS and Herschel-ATLAS. This second public data release of VIKING data covers all of the highest quality data taken between the start of the survey (12th of November 2009) and the end of Period 92 (30th September 2013). This release supersedes the first release (VIKING and VIKING CAT published 28.06.2013 and 16.12.2013 respectively) as it includes improved CASU processing (V1.3) that gives better tile grouting and zero point corrections This release contains 396 tiles with coverage in all five VIKING filters, 379 of which have a deep co-add in J, and an additional 81 with at least two filters where the second OB has not been executed yet or one filter in an OB was poor quality. These 477 fields cover a total of ~690 square degrees and the resulting catalogues include a total of 46,270,162 sources (including low-reliability single-band detections). The imaging and catalogues (both single-band and band-merged) total 839.3GB. The coverage in each of the five sub-areas is not completely contiguous but any inter-tile gaps are relatively small. More details can be found in the accompanying documentation: viking_cat_dr2.pdf
- ID:
- ivo://CDS.VizieR/J/A+A/562/A23
- Title:
- VIMOS Public Extragalactic Survey (VIPERS) DR1
- Short Name:
- J/A+A/562/A23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first Public Data Release (PDR-1) of the VIMOS Public Extragalactic Survey (VIPERS). It comprises 57204 spectroscopic measurements together with all additional information necessary for optimal scientific exploitation of the data, in particular the associated photometric measurements and quantification of the photometric and survey completeness. VIPERS is an ESO Large Programme designed to build a spectroscopic sample of =~100000 galaxies with i_AB_<22.5 and 0.5<z<1.2 with high sampling rate (=~45%). The survey spectroscopic targets are selected from the CFHTLS-Wide five-band catalogues in the W1 and W4 fields. The final survey will cover a total area of nearly 24 deg^2^, for a total comoving volume between z=0.5 and 1.2 of =~4x10^7^(Mpc/h)^3^ and a median galaxy redshift of z=~0.8. The release presented in this paper includes data from virtually the entire W4 field and nearly half of the W1 area, thus representing 64% of the final dataset. We provide a detailed description of sample selection, observations and data reduction procedures; we summarise the global properties of the spectroscopic catalogue and explain the associated data products and their use, and provide all the details for accessing the data through the survey database (http://vipers.inaf.it) where all information can be queried interactively.
