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- ID:
- ivo://CDS.VizieR/J/A+A/646/A83
- Title:
- 12 massive lensing clusters MUSE observations
- Short Name:
- J/A+A/646/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic surveys of massive galaxy clusters reveal the properties of faint background galaxies thanks to the magnification provided by strong gravitational lensing. We present a systematic analysis of integral-field- spectroscopy observations of 12 massive clusters, conducted with the Multi Unit Spectroscopic Explorer (MUSE). All data were taken under very good seeing conditions (~0.6") in effective exposure times between two and 15 hrs per pointing, for a total of 125 hrs. Our observations cover a total solid angle of ~23-arcmin^2^ in the direction of clusters, many of which were previously studied by the MAssive Clusters Survey (MACS), Frontier Fields (FFs), Grism Lens-Amplified Survey from Space (GLASS) and Cluster Lensing And Supernova survey with Hubble (CLASH) programmes. The achieved emission line detection limit at 5sigma for a point source varies between (0.77-1.5)x10^-18^erg/s/cm^2^ at 7000{AA}. We present our developed strategy to reduce these observational data, detect continuum sources and line emitters in the datacubes, and determine their redshifts. We constructed robust mass models for each cluster to further confirm our redshift measurements using strong-lensing constraints, and identified a total of 312 strongly lensed sources producing 939 multiple images. The final redshift catalogues contain more than 3300 robust redshifts, of which 40% are for cluster members and ~30% are for lensed Lyman-alpha emitters. Fourteen percent of all sources are line emitters that are not seen in the available HST images, even at the depth of the FFs (~29 AB). We find that the magnification distribution of the lensed sources in the high- magnification regime (mu=2-25) follows the theoretical expectation of N(z){prop.to}mu^-2^. The quality of this dataset, number of lensed sources, and number of strong-lensing constraints enables detailed studies of the physical properties of both the lensing cluster and the background galaxies. The full data products from this work, including the datacubes, catalogues, extracted spectra, ancillary images, and mass models, are made available to the community.
- ID:
- ivo://CDS.VizieR/J/MNRAS/441/203
- Title:
- Massive quiescent ETG in clusters
- Short Name:
- J/MNRAS/441/203
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyse the mass-size relation of ~400 quiescent massive ETGs (M*/M_{sun}_>3x10^10^) hosted by massive clusters (M200~2-7x10^14^M_{sun}_) at 0.8<z<1.5, compared to those found in the field at the same epoch. Size is parametrized using the mass-normalized B-band rest-frame size, {gamma}=R_e_/M_11_^0.57^. We find that the {gamma} distributions in both environments peak at the same position, but the distributions in clusters are more skewed towards larger sizes. This tail induces average sizes ~ 30-40 percent larger for cluster galaxies than for field galaxies of similar stellar mass, while the median sizes are statistically the same with a difference of ~10+/-10%. Since this size difference is not observed in the local Universe, the evolution of average galaxy size at fixed stellar mass from z~1.5 for cluster galaxies is less steep at more than 3{sigma}({prop.to}(1+z)-0.53+/-0.04) than the evolution of field galaxies ({prop.to}(1+z)-0.92+/-0.04). The difference in evolution is not measured when the median values of {gamma} are considered: {prop.to}(1+z)-0.84+/-0.04 in the field versus {prop.to}(1+z)-0.71+/-0.05 in clusters. In our sample, the tail of large galaxies is dominated by galaxies with 3x10^10^<M*/M_{sun}_<10^11^. At this low-mass end, the difference in the average size is better explained by the accretion of new galaxies that are quenched more efficiently in clusters and/or by different morphological mixing in the cluster and field environments. If part of the size evolution would be due to mergers, the difference that we see between cluster and field galaxies could be caused by higher merger rates in clusters at higher redshift, when galaxy velocities are lower.
- ID:
- ivo://CDS.VizieR/J/ApJ/772/25
- Title:
- Massive SZE clusters observations with ACT
- Short Name:
- J/ApJ/772/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first dynamical mass estimates and scaling relations for a sample of Sunyaev-Zel'dovich effect (SZE) selected galaxy clusters. The sample consists of 16 massive clusters detected with the Atacama Cosmology Telescope (ACT) over a 455deg^2^ area of the southern sky. Deep multi-object spectroscopic observations were taken to secure intermediate-resolution (R~700-800) spectra and redshifts for {approx}60 member galaxies on average per cluster. The dynamical masses M_200c_ of the clusters have been calculated using simulation-based scaling relations between velocity dispersion and mass. The sample has a median redshift z=0.50 and a median mass M_200c_~12x10^14^h_70_^-1^M_{sun}_ with a lower limit M_200c_~6x10^14^h_70_^-1^M_{sun}_, consistent with the expectations for the ACT southern sky survey. These masses are compared to the ACT SZE properties of the sample, specifically, the match-filtered central SZE amplitude {overline}{y_0_}, the central Compton parameter y_0_, and the integrated Compton signal Y_200c_, which we use to derive SZE-mass scaling relations. All SZE estimators correlate with dynamical mass with low intrinsic scatter (<~20%), in agreement with numerical simulations. We explore the effects of various systematic effects on these scaling relations, including the correlation between observables and the influence of dynamically disturbed clusters. Using the three-dimensional information available, we divide the sample into relaxed and disturbed clusters and find that ~50% of the clusters are disturbed. There are hints that disturbed systems might bias the scaling relations, but given the current sample sizes, these differences are not significant; further studies including more clusters are required to assess the impact of these clusters on the scaling relations.
- ID:
- ivo://CDS.VizieR/J/ApJ/867/12
- Title:
- Mass-richness relations for X-ray and SZE clusters
- Short Name:
- J/ApJ/867/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the mass-richness relation of 116 spectroscopically confirmed massive clusters at 0.4<z<2 by mining the Spitzer archive. We homogeneously measure the richness at 4.5um for our cluster sample within a fixed aperture of 2' radius and above a fixed brightness threshold, making appropriate corrections for both background galaxies and foreground stars. We have two subsamples, those which have (a) literature X-ray luminosities and (b) literature Sunyaev-Zel'dovich effect masses. For the X-ray subsample we re-derive masses adopting the most recent calibrations. We then calibrate an empirical mass-richness relation for the combined sample spanning more than one decade in cluster mass and find the associated uncertainties in mass at fixed richness to be +/-0.25dex. We study the dependence of the scatter of this relation with galaxy concentration, defined as the ratio between richness measured within an aperture radius of 1' and 2'. We find that at fixed aperture radius the scatter increases for clusters with higher concentrations. We study the dependence of our richness estimates with depth of the 4.5um imaging data and find that reaching a depth of at least [4.5]=21(AB)mag is sufficient to derive reasonable mass estimates. We discuss the possible extension of our method to the mid-infrared WISE All Sky Survey data and the application of our results to the Euclid mission. This technique makes richness-based cluster mass estimates available for large samples of clusters at very low observational cost.
- ID:
- ivo://CDS.VizieR/J/ApJ/569/720
- Title:
- Mass-to-light ratio of galaxy systems
- Short Name:
- J/ApJ/569/720
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the mass-to-light ratio of galaxy systems from poor groups to rich clusters and present for the first time a large database for useful comparisons with theoretical predictions. We extend a previous work, where B_j_ band luminosities and optical virial masses were analyzed for a sample of 89 clusters. Here we also consider a sample of 52 more clusters, 36 poor clusters, seven rich groups, and two catalogs, of ~500 groups each, recently identified in the Nearby Optical Galaxy sample by using two different algorithms. We obtain the blue luminosity and virial mass for all systems considered. We devote a large effort to establishing the homogeneity of the resulting values, as well as to considering comparable physical regions, i.e., those included within the virial radius.
- ID:
- ivo://CDS.VizieR/J/MNRAS/475/343
- Title:
- 2MASS, WISE, and SuperCOSMOS clusters of galaxies
- Short Name:
- J/MNRAS/475/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We identify 47600 clusters of galaxies from photometric data of Two Micron All Sky Survey (2MASS), Wide-field Infrared Survey Explorer (WISE), and SuperCOSMOS, among which 26125 clusters are recognized for the first time and mostly in the sky outside the Sloan Digital Sky Survey (SDSS) area. About 90 per cent of massive clusters of M_500_>3x10^14^M_{sun}_ in the redshift range of 0.025<z<0.3 have been detected from such survey data, and the detection rate drops down to 50 per cent for clusters with a mass of M_500_~1x10^14^M_{sun}_. Monte Carlo simulations show that the false detection rate for the whole cluster sample is less than 5 per cent. By cross-matching with ROSAT and XMM-Newton sources, we get 779 new X-ray cluster candidates which have X-ray counterparts within a projected offset of 0.2Mpc.
- ID:
- ivo://CDS.VizieR/J/ApJ/660/239
- Title:
- MaxBCG catalog of 13823 galaxy clusters from SDSS
- Short Name:
- J/ApJ/660/239
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of galaxy clusters selected using the maxBCG red-sequence method from Sloan Digital Sky Survey photometric data. This catalog includes 13823 clusters with velocity dispersions greater than ~400km/s and is the largest galaxy cluster catalog assembled to date. They are selected in an approximately volume-limited way from a 0.5Gpc^3^ region covering 7500deg^2^ of sky between redshifts 0.1 and 0.3. Each cluster contains between 10 and 190 E/S0 ridgeline galaxies brighter than 0.4L* within a scaled radius R_200_.
- ID:
- ivo://CDS.VizieR/J/ApJ/805/143
- Title:
- MC2: redshift analysis of CIZA J2242.8+5301
- Short Name:
- J/ApJ/805/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- X-ray and radio observations of CIZA J2242.8+5301 suggest that it is a major cluster merger. Despite being well studied in the X-ray and radio, little has been presented on the cluster structure and dynamics inferred from its galaxy population. We carried out a deep (i<25) broadband imaging survey of the system with Subaru SuprimeCam (g and i bands) and the Canada-France-Hawaii Telescope (r band), as well as a comprehensive spectroscopic survey of the cluster area (505 redshifts) using Keck DEep Imaging Multi-Object Spectrograph. We use these data to perform a comprehensive galaxy/redshift analysis of the system, which is the first step to a proper understanding of the geometry and dynamics of the merger, as well as using the merger to constrain self-interacting dark matter. We find that the system is dominated by two subclusters of comparable richness with a projected separation of 6.9'_-0.5_^+0.7^ (1.3_-0.10_^+0.13^Mpc). We find that the north and south subclusters have similar redshifts of z~0.188 with a relative line-of-sight (LOS) velocity difference of 69+/-190km/s. We also find that north and south subclusters have velocity dispersions of 1160_-90_^+100^ and 1080_-70_^+100^km/s, respectively. These correspond to masses of 16.1_-3.3_^+4.6^x10^14^ and 13.0_-2.5_^+4.0^x10^14^M_{Sun}_, respectively. While velocity dispersion measurements of merging clusters can be biased, we believe the bias in this system to be minor due to the large projected separation and nearly plane-of-sky merger configuration. We also find that the cDs of the north and south subclusters are very near their subcluster centers, in both projection (55 and 85kpc, respectively) and normalized LOS velocity (|{Delta}v|/{sigma}_v_=0.43+/-0.13 and 0.21+/-0.12 for the north and south, respectively). CIZA J2242.8+5301 is a relatively clean dissociative cluster merger with near 1:1 mass ratio, which makes it an ideal merger for studying merger-associated physical phenomena.
- ID:
- ivo://CDS.VizieR/J/MNRAS/450/630
- Title:
- MC2: SFR in CIZA J2242.8+5301
- Short Name:
- J/MNRAS/450/630
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Cluster mergers may play a fundamental role in the formation and evolution of cluster galaxies. Stroe et al. (2015MNRAS.450..646S) revealed unexpected overdensities of candidate H{alpha} emitters near the ~1-Mpc-wide shock fronts of the massive (~2x10^15^M_{sun}_) 'Sausage' merging cluster, CIZA J2242.8+5301. We used the Keck/Deep Imaging Multi-Object Spectrograph and the William Herschel Telescope/AutoFib2+WYFFOS to confirm 83 H{alpha} emitters in and around the merging cluster. We find that cluster star-forming galaxies in the hottest X-ray gas and/or in the cluster subcores (away from the shock fronts) show high [SII]6716/[SII]6761 and high [SII] 716/H{alpha}, implying very low electron densities (<30xlower than all other star-forming galaxies outside the cluster) and/or significant contribution from supernovae, respectively. All cluster star-forming galaxies near the cluster centre show evidence of significant outflows (blueshifted Na D ~ 200-300km/s), likely driven by supernovae. Strong outflows are also found for the cluster H{alpha} active galactic nucleus (AGN). H{alpha} star-forming galaxies in the merging cluster follow the z~0 mass-metallicity relation, showing systematically higher metallicity (~0.15-0.2dex) than H{alpha} emitters outside the cluster (projected R>2.5Mpc). This suggests that the shock front may have triggered remaining metal-rich gas which galaxies were able to retain into forming stars. Our observations show that the merger of impressively massive (~10^15^M_{sun}_) clusters can provide the conditions for significant star formation and AGN activity, but, as we witness strong feedback by star-forming galaxies and AGN (and given how massive the merging cluster is), such sources will likely quench in a few 100Myr.
