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2211. Very Small Array. Flux density at 33GHz
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.
2212. 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.
2213. VIc photometry of NGC 2547 low-mass stars
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.
2214. VIKING catalogue data release 2
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
2215. VIKING catalogue data release 1
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
2216. VIMOS Public Extragalactic Survey (VIPERS) DR1
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.
2217. VIMOS Ultra Deep Survey (VUDS) DR1
ID:
ivo://CDS.VizieR/J/A+A/600/A110
Title:
VIMOS Ultra Deep Survey (VUDS) DR1
Short Name:
J/A+A/600/A110
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper describes the first data release (DR1) of the VIMOS Ultra Deep Survey (VUDS). The VUDS-DR1 is the release of all low-resolution spectroscopic data obtained in 276.9 arcmin^2^ of the CANDELS-COSMOS and CANDELS-ECDFS survey areas, including accurate spectroscopic redshifts z_spec_ and individual spectra obtained with VIMOS on the ESO-VLT. A total of 698 objects have a measured redshift, with 677 galaxies, two type-I AGN, and a small number of 19 contaminating stars. The targets of the spectroscopic survey are selected primarily on the basis of their photometric redshifts to ensure a broad population coverage. About 500 galaxies have z_spec_>2, 48of which have z_spec_>4; the highest reliable redshifts reach beyond z_spec_=6. This data set approximately doubles the number of galaxies with spectroscopic redshifts at z>3 in these fields. We discuss the general properties of the VUDS-DR1 sample in terms of the spectroscopic redshift distribution, the distribution of Lyman-{alpha} equivalent widths, and physical properties including stellar masses M* and star formation rates derived from spectral energy distribution fitting with the knowledge of z_spec_. We highlight the properties of the most massive star-forming galaxies, noting the wide range in spectral properties, with Lyman-{alpha} in emission or in absorption, and in imaging properties with compact, multi-component, or pair morphologies. We present the catalogue database and data products. All VUDS-DR1 data are publicly available and can be retrieved from a dedicated query-based database. Future VUDS data releases will follow this VUDS-DR1 to give access to the spectra and associated measurement of ~8000 objects in the full ~1 square degree of the VUDS survey.
2218. VIMOS VLT Deep Survey: faint type-1 AGN sample
ID:
ivo://CDS.VizieR/J/A+A/457/79
Title:
VIMOS VLT Deep Survey: faint type-1 AGN sample
Short Name:
J/A+A/457/79
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the type-1 active galactic nuclei (AGN) sample extracted from the VIMOS VLT Deep Survey's first observations of 21000 spectra in 1.75{deg}^2^. This sample, which is purely magnitude-limited and free of morphological or color-selection biases, contains 130 broad-line AGN (BLAGN) spectra with redshift up to 5. Our data are divided into a wide (I_AB_<=22.5) and a deep (I_AB_<=24) subsample containing 56 and 74 objects, respectively. Because of its depth and selection criteria, this sample is uniquely suited for studying the population of faint type-1 AGN. Our measured surface density (~472+/-48 BLAGN per square degree with I_AB_<=24) is significantly higher than that of any other optically selected sample of BLAGN with spectroscopic confirmation. By applying a morphological and color analysis to our AGN sample, we find that (1) ~23% of the AGN brighter than I_AB_=22.5 are classified as extended, and this percentage increases to ~42 for those with z<1.6; (2) a non-negligible fraction of our BLAGN are lying close to the color-space area occupied by stars in the u*-g' versus g'-r' color-color diagram. This leads us to the conclusion that the classical optical-ultraviolet preselection technique, if employed at such deep magnitudes (I_AB_=22.5) in conjuction with a preselection of point-like sources, can miss up to ~35% of the AGN population. Finally, we present a composite spectrum of our sample of objects. While the continuum shape is very similar to that of the SDSS composite at short wavelengths, it is much redder than that of the SDSS composite at {lambda}>=3000{AA}. We interpret this as due to significant contamination from emission of the host galaxies, as expected from the faint absolute magnitudes sampled by our survey.
2219. VIMOS VLT Deep Survey final data release
ID:
ivo://CDS.VizieR/J/A+A/559/A14
Title:
VIMOS VLT Deep Survey final data release
Short Name:
J/A+A/559/A14
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep representative surveys of galaxies at different epochs are needed to make progress in understanding galaxy evolution. We describe the completed VIMOS VLT Deep Survey and the final data release of 35016 galaxies and type-I AGN with measured spectroscopic redshifts covering all epochs up to redshift z~6.7, in areas from 0.142 to 8.7 square degrees, and volumes from 0.5x10^6^ to 2x10^7^h^-3^*Mpc^3^. We selected samples of galaxies based solely on their i-band magnitude reaching i_AB_=24.75. Spectra were obtained with VIMOS on the ESO-VLT integrating 0.75h, 4.5h, and 18h for the Wide, Deep, and Ultra-Deep nested surveys, respectively. We demonstrate that any "redshift desert" can be crossed successfully using spectra covering 3650<={lambda}<=9350{AA}. A total of 1263 galaxies were again observed independently within the VVDS and from the VIPERS and MASSIV surveys. They were used to establish the redshift measurements reliability, to assess completeness in the VVDS sample, and to provide a weighting scheme taking the survey selection function into account. We describe the main properties of the VVDS samples, and the VVDS is compared to other spectroscopic surveys in the literature. In total we have obtained spectroscopic redshifts for 34594 galaxies, 422 type-I AGN, and 12430 Galactic stars. The survey enabled identifying galaxies up to very high redshifts with 4669 redshifts in 1<=z_spec_<=2, 561 in 2<=z_spec_<=3, and 468 with z_spec_>3, and specific populations like Lyman-{alpha} emitters were identified out to z=6.62. We show that the VVDS occupies a unique place in the parameter space defined by area, depth, redshift coverage, and number of spectra. The VIMOS VLT Deep Survey provides a comprehensive survey of the distant universe, covering all epochs since z~6, or more than 12Gyr of cosmic time, with a uniform selection, which is the largest such sample to date. A wealth of science results derived from the VVDS have shed new light on the evolution of galaxies and AGN and on their distribution in space over this large cosmic time. The VVDS further demonstrates that large deep spectroscopic redshift surveys over all these epochs in the distant Universe are a key tool to observational cosmology. To enhance the legacy value of the survey, a final public release of the complete VVDS spectroscopic redshift sample is available at http://cesam.lam.fr/vvds .
2220. VIPERS: galaxy colours and luminosity function
ID:
ivo://CDS.VizieR/J/A+A/563/A92
Title:
VIPERS: galaxy colours and luminosity function
Short Name:
J/A+A/563/A92
Date:
21 Oct 2021
Publisher:
CDS
Description:
We explore the evolution of the colour-magnitude relation (CMR) and luminosity function (LF) at 0.4<z<1.3 from the VIMOS Public Extragalactic Redshift Survey (VIPERS) using ~45000 galaxies with precise spectroscopic redshifts down to i'_AB_<22.5 over ~10.32deg^2^ in two fields. From z=0.5 to z=1.3 the LF and CMR are well defined for different galaxy populations and M^*^_B_ evolves by ~1.04(1.09)+/-0.06(0.10) mag for the total (red) galaxy sample. We compare different criteria for selecting early-type galaxies: (1) a fixed cut in rest-frame (U-V) colours, (2) an evolving cut in (U-V) colours, (3) a rest-frame (NUV-r')-(r'-K) colour selection, and (4) a spectral-energy-distribution classification. The completeness and contamination varies for the different methods and with redshift, but regardless of the method we measure a consistent evolution of the red-sequence (RS). Between 0.4<z<1.3 we find a moderate evolution of the RS intercept of {Delta}(U-V)=0.28+/-0.14 mag, favouring exponentially declining star formation (SF) histories with SF truncation at 1.7<=z<=2.3. Together with the rise in the number density of red galaxies by 0.64dex since z=1, this suggests a rapid build-up of massive galaxies (M_*_>10^11^M_{sun}_) and expeditious RS formation over a short period of ~1.5Gyr starting before z=1. This is supported by the detection of ongoing SF in early-type galaxies at 0.9<z<1.0, in contrast with the quiescent red stellar populations of early-type galaxies at 0.5<z<0.6. There is an increase in the observed CMR scatter with redshift, which is two times larger than observed in galaxy clusters and at variance with theoretical model predictions. We discuss possible physical mechanisms that support the observed evolution of the red galaxy population. Our findings point out that massive galaxies have experienced a sharp SF quenching at z~1 with only limited additional merging. In contrast, less-massive galaxies experience a mix of SF truncation and minor mergers which build-up the low- and intermediate-mass end of the CMR.

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