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- ID:
- ivo://CDS.VizieR/J/AJ/122/1125
- Title:
- BVRI photometry in 3 high-z clusters
- Short Name:
- J/AJ/122/1125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New photometric and spectroscopic observations of galaxies in the directions of three distant clusters are presented as part of our ongoing high-redshift cluster survey. The clusters are Cl 1324+3011 at z=0.76, Cl 1604+4304 at z=0.90, and Cl 1604+4321 at z=0.92. We have spectroscopically confirmed cluster membership for 2040 galaxies in each system and have also obtained spectra for over 280 field galaxies spanning the range 0<z<2.5.
- ID:
- ivo://CDS.VizieR/J/A+A/382/60
- Title:
- BVR photometry in Abell 1689
- Short Name:
- J/A+A/382/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At a redshift of 0.18, Abell 1689 is so far the most distant cluster of galaxies for which substantial mid-infrared (MIR) data have been published. Its mapping with the ISOCAM camera onboard the ISO satellite allowed the detection of 30 cluster members at 6.75{mu}m (LW2 filter) and 16 cluster members at 15{mu}m (LW3 filter) within a clustercentric radius of 0.5Mpc (Fadda et al., 2000A&A...361..827F, Paper I). We present here the follow-up optical photometric and spectroscopic observations which were used to study the individual properties of the galaxy members of A1689. We confirm the high fraction of blue galaxies initially reported in this rich cluster by Butcher & Oemler (1984ApJ...285..426B), that was challenged by some subsequent studies. We discuss the spectral and morphological properties of all cluster members in our spectroscopic sample, and of the MIR-detected galaxies in particular.
- ID:
- ivo://CDS.VizieR/J/AJ/120/2190
- Title:
- Caltech Faint Galaxy Redshift Survey. XIV
- Short Name:
- J/AJ/120/2190
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Morphological classifications are reported for Hubble Space Telescope images of 241 galaxies in the Hubble Deep Field and its flanking fields with measured redshifts in the interval 0.25<z<1.2, drawn from a magnitude-limited redshift survey to R=24.0. The galaxies are divided into three groups with redshifts in the intervals 0.25-0.6, 0.6-0.8, and 0.8-1.2. R_606_ images from the first group and I814 images from the second and third groups are compared with B-band images of nearby galaxies. All classifications were therefore made at approximately the same rest wavelength. Selection biases are discussed.
- ID:
- ivo://CDS.VizieR/J/AJ/122/611
- Title:
- Caltech Faint Galaxy Redshift Survey. XV.
- Short Name:
- J/AJ/122/611
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To circumvent the spatial effects of resolution on galaxy classification, the images of 233 objects of known redshift in the Hubble Deep Field (HDF) and its flanking fields that have redshifts in the range 0.20<z<1.10 were degraded to the resolution that they would have had if they were all located at a redshift of z=1.00. As in Paper XIV (Cat. <J/AJ/120/2190>) of the present series, the effects of shifts in rest wavelength were mitigated by using R-band images for the classification of galaxies with 0.2<z<0.6 and I-band images for objects with redshifts 0.6<z<1.1. A special effort was made to search for bars in distant galaxies. The present data strongly confirm the previous conclusion that the Hubble tuning fork diagram only provides a satisfactory framework for the classification of galaxies with z<0.3. More distant disk galaxies are often difficult to shoehorn into the Hubble classification scheme. The paucity of barred spirals and grand-design spirals at large redshifts is confirmed. It is concluded that the morphology of disk galaxies observed at look-back times smaller than 3-4Gyr differs systematically from that of more distant galaxies viewed at look-back times of 4-8Gyr. The disks of late-type spirals at z>0.5 are seen to be more chaotic than those of their nearer counterparts. Furthermore, the spiral structure in distant early-type spirals appears to be less well developed than it is in nearby early galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/206/10
- Title:
- CANDELS multiwavelength catalog
- Short Name:
- J/ApJS/206/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multiwavelength ultraviolet to mid-infrared catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, Rc, i', and z' band data from Subaru/Suprime-Cam; Y and Ks band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5um from SEDS; 5.8 and 8.0um from SpUDS). The present catalog is F160W-selected and contains 35932 sources over an area of 201.7arcmin^2^ and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.
- ID:
- ivo://CDS.VizieR/J/ApJS/229/32
- Title:
- CANDELS: multiwavelength catalogs in the EGS
- Short Name:
- J/ApJS/229/32
- Date:
- 03 Nov 2021 09:14:43
- Publisher:
- CDS
- Description:
- We present a 0.4-8{mu}m multi-wavelength photometric catalog in the Extended Groth Strip (EGS) field. This catalog is built on the Hubble Space Telescope (HST) WFC3 and ACS data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), and it incorporates the existing HST data from the All-wavelength Extended Groth strip International Survey (AEGIS) and the 3D-HST program. The catalog is based on detections in the F160W band reaching a depth of F160W=26.62 AB (90% completeness, point sources). It includes the photometry for 41457 objects over an area of ~206arcmin^2^ in the following bands: HST/ACS F606W and F814W; HST WFC3 F125W, F140W, and F160W; Canada-France-Hawaii Telescope (CFHT)/Megacam u*, g' , r', i' and z'; CFHT/WIRCAM J, H, and K_S_; Mayall/NEWFIRM J1, J2, J3, H1, H2, and K; Spitzer IRAC 3.6, 4.5, 5.8, and 8.0{mu}m. We are also releasing value-added catalogs that provide robust photometric redshifts and stellar mass measurements.
- ID:
- ivo://CDS.VizieR/J/ApJ/775/106
- Title:
- CANDELS passive and massive early-type galaxies
- Short Name:
- J/ApJ/775/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the evolution of the number density, as a function of the size, of passive early-type galaxies (ETGs) with a wide range of stellar masses (10^10^M_{sun}_<M_*_<~10^11.5^M_{sun}_) from z~3 to z~1, exploiting the unique data set available in the GOODS-South field, including the recently obtained WFC3 images as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). In particular, we select a sample of ~107 massive (M_*_>10^10^M_{sun}_), passive (SSFR<10^-2^/Gyr), and morphologically spheroidal galaxies at 1.2<z<3, taking advantage of the panchromatic data set available for GOODS, including VLT, CFHT, Spitzer, Chandra, and HST ACS+WFC3 data. We find that at 1<z<3 the passively evolving ETGs are the reddest and most massive objects in the universe, and we prove that a correlation between mass, morphology, color, and star formation activity is already in place at that epoch. We measure a significant evolution in the mass-size relation of passive ETGs from z~3 to z~1, with galaxies growing on average by a factor of two in size in a 3Gyr timescale only. We also witness an increase in the number density of passive ETGs of 50 times over the same time interval. We find that the first ETGs to form at z>~2 are all compact or ultra-compact, while normal-sized ETGs (meaning ETGs with sizes comparable to those of local counterparts of the same mass) are the most common ETGs only at z<1. The increase of the average size of ETGs at 0<z<1 is primarily driven by the appearance of new large ETGs rather than by the size increase of individual galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/793/101
- Title:
- CANDELS z~2 galaxy properties
- Short Name:
- J/ApJ/793/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use CANDELS imaging, 3D-HST spectroscopy, and Chandra X-ray data to investigate if active galactic nuclei (AGNs) are preferentially fueled by violent disk instabilities funneling gas into galaxy centers at 1.3<z<2.4. We select galaxies undergoing gravitational instabilities using the number of clumps and degree of patchiness as proxies. The CANDELS visual classification system is used to identify 44 clumpy disk galaxies, along with mass-matched comparison samples of smooth and intermediate morphology galaxies. We note that despite being mass-matched and having similar star formation rates, the smoother galaxies tend to be smaller disks with more prominent bulges compared to the clumpy galaxies. The lack of smooth extended disks is probably a general feature of the z~2 galaxy population, and means we cannot directly compare with the clumpy and smooth extended disks observed at lower redshift. We find that z~2 clumpy galaxies have slightly enhanced AGN fractions selected by integrated line ratios (in the mass-excitation method), but the spatially resolved line ratios indicate this is likely due to extended phenomena rather than nuclear AGNs. Meanwhile, the X-ray data show that clumpy, smooth, and intermediate galaxies have nearly indistinguishable AGN fractions derived from both individual detections and stacked non-detections. The data demonstrate that AGN fueling modes at z~1.85 - whether violent disk instabilities or secular processes - are as efficient in smooth galaxies as they are in clumpy galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/509/A81
- Title:
- Candidate clusters detected in six CFHTLS fields
- Short Name:
- J/A+A/509/A81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Counting clusters is one of the methods to constrain cosmological parameters, but has been limited up to now both by the redshift range and by the relatively small sizes of the homogeneously surveyed areas. In order to enlarge publicly available optical cluster catalogs, in particular at high redshift, we have performed a systematic search for clusters of galaxies in the Canada France Hawaii Telescope Legacy Survey (CFHTLS). We considered the deep 2, 3 and 4 CFHTLS Deep fields (each 1x1deg^2^), as well as the wide 1, 3 and 4 CFHTLS Wide fields. We used the Le Phare photometric redshifts for the galaxies detected in these fields with magnitude limits of i'=25 and 23 for the Deep and Wide fields respectively. We then constructed galaxy density maps in photometric redshift bins of 0.1 based on an adaptive kernel technique and detected structures with SExtractor at various detection levels. In order to assess the validity of our cluster detection rates, we applied a similar procedure to galaxies in Millennium simulations. We measured the correlation function of our cluster candidates. We analyzed large scale properties and substructures, including filaments, by applying a minimal spanning tree algorithm both to our data and to the Millennium simulations.