The VIMOS VLT Deep Survey final data release: a spectroscopic sample of 35 016 galaxies and AGN out toz~ 6.7 selected with 17.5 ≤i_AB ≤ 24.75

Abstract

Context. Deep representative surveys of galaxies at different epochs are needed to make progress in understanding galaxy evolution. Aims. We describe the completed VIMOS VLT Deep Survey and the final data release of 35 016 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 0.5×10 6 to 2×10 7 h −3 Mpc 3 . Methods. 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 0.75 h, 4.5 h, and 18 h for the Wide, Deep, and Ultra-Deep nested surveys, respectively. We demonstrate that any "redshift desert" can be crossed successfully using spectra covering 3650 ≤ λ ≤ 9350 Å. 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. Results. In total we have obtained spectroscopic redshifts for 34 594 galaxies, 422 type-I AGN, and 12 430 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-α 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. Conclusions. The VIMOS VLT Deep Survey provides a comprehensive survey of the distant universe, covering all epochs since z ∼ 6, or more than 12 Gyr 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.

The CFHT Large Area U-band Deep Survey (CLAUDS)

“…data dramatically improves the quality of photometric redshifts. In this Figure we compare our photometric redshifts calculated without U-band (top panel) and with (bottom panel) against 22,005 high-quality spectroscopic redshifts we extracted from a compilation of surveys in our fields (Bradshaw et al 2013;Comparat et al 2015;Le Févre et al 2013;Kriek et al 2015;Lilly et al 2007;Masters et al 2017;McLure et al 2013;Scodeggio et al 2018;Silverman et al 2015;Tasca et al 2017, and D. Masters, private communication). Of these redshifts, 13,779 have z spec < 0.75 (604 of these are stars and were excluded from the sample) and 1,213 are at 2 < z spec < 3.5.…”

Galaxy–Galaxy lensing in HSC: Validation tests and the impact of heterogeneous spectroscopic training sets

“…In addition to these spec-z's, grism-z's, and prismz's, the training set was supplemented with a set of highquality, many-band photo-z's taken from 3D-HST and COS-MOS2015 (Laigle et al 2016) in order to maintain sufficient magnitude and color coverage down to i ∼ 24.5 (see §3). Without these photo-z's, the magnitude and color coverage of the training set fails to adequately span the relevant parameter space of the HSC-SSP data used in this analysis.…”

Nature of Faint Radio Sources in GOODS-North and GOODS-South Fields. I. Spectral Index and Radio–FIR Correlation

“…Spectroscopic redshifts are compiled from the published surveys: GN (Cowie et al 2004;Donley et al 3 Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. 4 Data are available at http://www.mpe.mpg.de/ir/Research/PEP/DR1 5 Data are available at http://hedam.lam.fr/HerMES/index/dr4 6 Reliability is defined as Rel i = LR i /(ΣLR i + (1 − q 0 )) for the likelihood ratio LR i and the fraction of true counterparts above the detection limit, q 0 7 Le P hare is available at http://www.cfht.hawaii.edu/ ∼arnouts/lephare.html 2007; Barger et al 2008;Wirth et al 2015) and GS (Szokoly et al 2004;Zheng et al 2004;Mignoli et al 2005;Ravikumar et al 2007;Vanzella et al 2008;Popesso et al 2009;Straughn et al 2009;Balestra et al 2010;Silverman et al 2010;Cooper et al 2012;Kurk et al 2013;Le Fèvre et al 2013;Skelton et al 2014;Morris et al 2015), respectively. From these compilations, we have 45 (out of 52) sources with spectroscopic redshifts for the GN and 55 (out of 64) for the GS field.…”