- ID:
- ivo://CDS.VizieR/J/ApJ/820/98
- Title:
- Galaxy candidates in the Hubble Frontier Fields
- Short Name:
- J/ApJ/820/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we present the results of our search for and study of z>~6 galaxy candidates behind the third Frontier Fields (FFs) cluster, MACS J0717.5+3745, and its parallel field, combining data from Hubble and Spitzer. We select 39 candidates using the Lyman break technique, for which the clear non-detection in optical make the extreme mid-z interlopers hypothesis unlikely. We also take benefit from z>~6 samples selected using the previous FF data sets of Abell 2744 and MACS 0416 to improve the constraints on the properties of very high redshift objects. We compute the redshift and the physical properties such emission lines properties, star formation rate, reddening, and stellar mass for all FF objects from their spectral energy distribution using templates including nebular emission lines. We study the relationship between several physical properties and confirm the trend already observed in previous surveys for evolution of star formation rate with galaxy mass and between the size and the UV luminosity of our candidates. The analysis of the evolution of the UV luminosity function with redshift seems more compatible with an evolution of density. Moreover, no robust z>=8.5 object is selected behind the cluster field and few z~9 candidates have been selected in the two previous data sets from this legacy survey, suggesting a strong evolution in the number density of galaxies between z~8 and 9. Thanks to the use of the lensing cluster, we study the evolution of the star formation rate density produced by galaxies with L>0.03 L_{star}_, and confirm the strong decrease observed between z~8 and 9.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/246/2
- Title:
- Galaxy cluster cat. from SDSS-DR13 (GalWCat19)
- Short Name:
- J/ApJS/246/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Utilizing the SDSS-DR13 spectroscopic data set, we create a new publicly available catalog of 1800 galaxy clusters (GalWeight cluster catalog, GalWCat19) and a corresponding catalog of 34,471 identified member galaxies. The clusters are identified from overdensities in redshift phase space. The GalWeight technique introduced by Abdullah+ (2018ApJ...861...22A) is then applied to identify cluster members. The completeness of the cluster catalog (GalWCat19) and the procedure followed to determine cluster mass are tested on the Bolshoi N-body simulations. The 1800 GalWCat19 clusters range in redshift between 0.01 and 0.2 and have masses in the range of (0.4-14)x10^14^h^-1^M_{sun}_. The cluster catalog provides a large number of cluster parameters, including sky position, redshift, membership, velocity dispersion, and mass at overdensities {Delta}=500, 200, 100, and 5.5. The 34471 member galaxies are identified within the radius at which the density is 200 times the critical density of the universe. The galaxy catalog provides the coordinates of each galaxy and the ID of the cluster that the galaxy belongs to. The cluster velocity dispersion scales with mass as log({sigma}_200_)=log(946+/-52km/s)+ (0.349+/-0.142)log[h(z)M_200_/10^1 5^M_{sun}], with a scatter of {delta}log{sigma}=0.06+/-0.04.
- ID:
- ivo://CDS.VizieR/J/ApJ/774/40
- Title:
- Galaxy clusters aligned with quasars. III.
- Short Name:
- J/ApJ/774/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Gemini/GMOS-S multi-object spectroscopy of 31 galaxy cluster candidates at redshifts between 0.2 and 1.0 and centered on QSO sight lines taken from Lopez et al. (Paper I, J/ApJ/679/1144). The targets were selected based on the presence of an intervening MgII absorption system at a similar redshift to that of a galaxy cluster candidate lying at a projected distance <2h_71_^-1^Mpc from the QSO sight line (a "photometric hit"). The absorption systems span rest-frame equivalent widths between 0.015 and 2.028{AA}. The general population of our confirmed absorbing galaxies have luminosities L_B_~L_B_^*^ and mean rest-frame colors (R_c_-z') typical of S_cd_ galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/763/127
- Title:
- Galaxy clusters discovered in the SPT survey
- Short Name:
- J/ApJ/763/127
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of galaxy cluster candidates, selected through their Sunyaev-Zel'dovich (SZ) effect signature in the first 720deg^2^ of the South Pole Telescope (SPT) survey. This area was mapped with the SPT in the 2008 and 2009 austral winters to a depth of ~18{mu}K_CMB_-arcmin at 150GHz; 550deg^2^ of it was also mapped to ~44{mu}K_CMB_-arcmin at 95GHz. Based on optical imaging of all 224 candidates and near-infrared imaging of the majority of candidates, we have found optical and/or infrared counterparts for 158, which we then classify as confirmed galaxy clusters. Of these 158 clusters, 135 were first identified as clusters in SPT data, including 117 new discoveries reported in this work. This catalog triples the number of confirmed galaxy clusters discovered through the SZ effect. We report photometrically derived (and in some cases spectroscopic) redshifts for confirmed clusters and redshift lower limits for the remaining candidates. The catalog extends to high redshift with a median redshift of z=0.55 and maximum confirmed redshift of z=1.37. Forty-five of the clusters have counterparts in the ROSAT bright or faint source catalogs from which we estimate X-ray fluxes. Based on simulations, we expect the catalog to be nearly 100% complete above M_500_{approx}5x10^14^M_{sun}_h^-1^_70_ at z>~0.6. There are 121 candidates detected at signal-to-noise ratio greater than five, at which the catalog purity is measured to be 95%.
- ID:
- ivo://CDS.VizieR/J/ApJS/216/27
- Title:
- Galaxy clusters discovered in the SPT-SZ survey
- Short Name:
- J/ApJS/216/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of galaxy clusters selected via their Sunyaev-Zel'dovich (SZ) effect signature from 2500deg^2^ of South Pole Telescope (SPT) data. This work represents the complete sample of clusters detected at high significance in the 2500deg^2^ SPT-SZ survey, which was completed in 2011. A total of 677 (409) cluster candidates are identified above a signal-to-noise threshold of {xi}=4.5 (5.0). Ground- and space-based optical and near-infrared (NIR) imaging confirms overdensities of similarly colored galaxies in the direction of 516 (or 76%) of the {xi}>4.5 candidates and 387 (or 95%) of the {xi}>5 candidates; the measured purity is consistent with expectations from simulations. Of these confirmed clusters, 415 were first identified in SPT data, including 251 new discoveries reported in this work. We estimate photometric redshifts for all candidates with identified optical and/or NIR counterparts; we additionally report redshifts derived from spectroscopic observations for 141 of these systems. The mass threshold of the catalog is roughly independent of redshift above z~0.25 leading to a sample of massive clusters that extends to high redshift. The median mass of the sample is M_500c_({rho}_crit_)~3.5x10^14^M_{sun}_h_70_^-1^, the median redshift is z_med_=0.55, and the highest-redshift systems are at z>1.4. The combination of large redshift extent, clean selection, and high typical mass makes this cluster sample of particular interest for cosmological analyses and studies of cluster formation and evolution.
- ID:
- ivo://CDS.VizieR/J/ApJS/253/56
- Title:
- Galaxy clusters from the DESI surveys. I.
- Short Name:
- J/ApJS/253/56
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- Based on the photometric redshift catalog of Zou+ (2019ApJS..242....8Z), we apply a fast clustering algorithm to identify 540432 galaxy clusters at z<=1 in the DESI legacy imaging surveys, which cover a sky area of about 20000deg^2^. Monte Carlo simulations indicate that the false-detection rate of our detecting method is about 3.1%. The total masses of galaxy clusters are derived using a calibrated richness-mass relation that is based on the observations of X-ray emission and the Sunyaev and Zel'dovich effect. The median redshift and mass of our detected clusters are about 0.53 and 1.23x10^14^M_{sun}_, respectively. Comparing with previous clusters identified using the data of the Sloan Digital Sky Survey; we can recognize most of them, especially those with high richness. Our catalog will be used for further statistical studies on galaxy clusters and environmental effects on galaxy evolution, etc.
- ID:
- ivo://CDS.VizieR/J/ApJS/183/197
- Title:
- Galaxy clusters identified from the SDSS-DR6
- Short Name:
- J/ApJS/183/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Clusters of galaxies in most of the previous catalogs have redshifts z<=0.3. Using the photometric redshifts of galaxies from the Sloan Digital Sky Survey Data Release 6 (SDSS DR6), we identify 39716 clusters in the redshift range 0.05<z<0.6 with more than eight luminous (M_r_<=-21) member galaxies. Cluster redshifts are estimated accurately with an uncertainty of less than 0.022. The contamination rate of member galaxies is found to be roughly 20%, and the completeness of member galaxy detection reaches ~90%. Monte Carlo simulations show that the cluster detection rate is more than 90% for massive (M_200_>2x10^14^M_{sun}_) clusters of z<=0.42. The false detection rate is ~5%. We obtain the richness, the summed luminosity, and the gross galaxy number within the determined radius for identified clusters. They are tightly related to the X-ray luminosity and temperature of clusters. Cluster mass is related to the richness and summed luminosity with M_200_{prop.to}R^1.90+/-0.04^ and M_200_{prop.to}L^1.64+/-0.03^_r_, respectively. In addition, 790 new candidates of X-ray clusters are found by cross-identification of our clusters with the source list of the ROSAT X-ray survey.
- ID:
- ivo://CDS.VizieR/J/ApJ/679/1144
- Title:
- Galaxy clusters in LOS to background QSOs. I.
- Short Name:
- J/ApJ/679/1144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the first optical survey of absorption systems associated with cluster galaxies at z=0.3-0.9. We have cross-correlated quasars from the third data release of the SDSS (Cat. VII/243) with high-redshift cluster/group candidates from the Red-Sequence Cluster Survey (Cat. J/ApJS/157/1). We have found 442 quasar-cluster pairs for which the MgII{lambda}2796, 2803 doublet might be detected at a transverse (physical) distance d<2h^-1^_71_Mpc from the cluster centers. To investigate the incidence dN/dz and equivalent width distribution n(W) of MgII systems at cluster redshifts, two statistical samples were drawn out of these pairs: one made of high-resolution spectroscopic quasar observations (46 pairs), and one made of quasars used in MgII searches found in the literature (375 pairs).
- ID:
- ivo://CDS.VizieR/J/A+A/578/A79
- Title:
- Galaxy clusters in SDSS Stripe 82
- Short Name:
- J/A+A/578/A79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The discovery of new galaxy clusters is important for two reasons. First, clusters are interesting per se, since their detailed analysis allows us to understand how galaxies form and evolve in various environments and second, they play an important part in cosmology because their number as a function of redshift gives constraints on cosmological parameters. We have searched for galaxy clusters in the Stripe 82 region of the Sloan Digital Sky Survey, and analysed various properties of the cluster galaxies. Based on a recent photometric redshift (hereafter photo-z) galaxy catalogue, we built a cluster catalogue by applying the Adami & MAzure Cluster FInder (AMACFI). Extensive tests were made to fine-tune the AMACFI parameters and make the cluster detection as reliable as possible. The same method was applied to the Millennium simulation to estimate our detection efficiency and the approximate masses of the detected clusters. Considering all the cluster galaxies (i.e. within a 1Mpc radius of the cluster to which they belong and with a photo-z differing by less than +/-0.05 from that of the cluster), we stacked clusters in various redshift bins to derive colour-magnitude diagrams and galaxy luminosity functions (GLFs). For each galaxy brighter than Mr<-19.0, we computed the disk and spheroid components by applying SExtractor, and by stacking clusters we determined how the disk-to-spheroid flux ratio varies with cluster redshift and mass.
- ID:
- ivo://CDS.VizieR/J/A+A/494/845
- Title:
- Galaxy clusters in the CFHTLS
- Short Name:
- J/A+A/494/845
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the gain of added leverage and completeness of the constructed cluster catalogue, of applying the matched-filter detection algorithm to multiple passbands. In particular, we investigate the gain from having both i'- and z'-band data available when searching for galaxy clusters at z>~1. We applied a matched filter detection method to the CFHTLS r'- and z'-band data of the four Deep fields and compared the cluster catalogues with the one extracted from the i'-band data presented in a previous paper. We also applied the matched filter to the Deep fields but with the limiting magnitudes appropriate for the much larger Wide survey in order to understand the best combination of i'- and z'-band depth for the most efficient cluster searches based on this algorithm.
