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- ID:
- ivo://CDS.VizieR/J/MNRAS/411/2009
- Title:
- H narrow-band imaging of XMMU J2235.3-2557
- Short Name:
- J/MNRAS/411/2009
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of a narrow-band photometric study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. We obtained deep H narrow-band imaging with the Near InfraRed Imager and Spectrometer on Gemini North, corresponding to H{alpha} emission at the cluster's redshift. Our sample consists of 82 galaxies within a radius of ~500kpc, 10 of which are spectroscopically confirmed cluster members. 16 galaxies are identified as excess line-emitters.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/3652
- Title:
- H narrow-band imaging of XMMU J2235.3-2557
- Short Name:
- J/MNRAS/423/3652
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extended narrow-band H{alpha} study of the massive galaxy cluster XMMU J2235.3-2557 at z=1.39. This paper represents a follow-up study to our previous investigation of star formation in the cluster centre, extending our analysis out to a projected cluster radius of 1.5Mpc. Using the Near InfraRed Imager and Spectrograph on Gemini North Telescope we obtained deep H narrow-band imaging corresponding to the rest-frame wavelength of H{alpha} at the cluster's redshift. We identify a total of 163 potential cluster members in both pointings, excluding stars based on their near-infrared colours derived from VLT/HAWK-I imaging. Of these 163 objects 14 are spectroscopically confirmed cluster members, and 20 per cent are excess line emitters. We find no evidence of star formation activity within a radius of 200 kpc of the brightest cluster galaxy in the cluster core. Dust-corrected star formation rates (SFRs) of excess emitters outside this cluster quenching radius, R_Q_~200kpc, are on average <SFR>=2.7+/-1.0M_{sun}_/yr, but do not show evidence of increasing SFRs towards the extreme 1.5Mpc radius of the cluster. No individual cluster galaxy exceeds an SFR of 6M_{sun}_/yr. Massive galaxies (logM*/M_{sun}_>10.75) all have low specific SFRs (SSFRs, i.e. SFR per unit stellar mass). At fixed stellar mass, galaxies in the cluster centre have lower SSFRs than the rest of the cluster galaxies, which in turn have lower SSFRs than field galaxies at the same redshift by a factor of a few to 10. For the first time we can demonstrate through measurements of individual SFRs that already at very early epochs (at an age of the Universe of ~4.5Gyr) the suppression of star formation is an effect of the cluster environment which persists at fixed galaxy stellar mass.
- ID:
- ivo://CDS.VizieR/J/A+A/258/243
- Title:
- HRV of Abell 151 galaxies
- Short Name:
- J/A+A/258/243
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a sample of 65 redshifts to study the kinematics and dynamics of the cluster Abell 151. Data on individual galaxies are presented, and the accuracy of the determined velocities are discussed as well as some properties of the cluster. The velocity data reveal a foreground group and a background population at the same redshifts as the closely projected cluster A 166.
- ID:
- ivo://CDS.VizieR/J/PASJ/70/S20
- Title:
- HSC Wide S16A cluster catalog
- Short Name:
- J/PASJ/70/S20
- Date:
- 02 Nov 2021 11:18:17
- Publisher:
- CDS
- Description:
- We present an optically-selected cluster catalog from the Hyper Suprime-Cam (HSC) Subaru Strategic Program. The HSC images are sufficiently deep to detect cluster member galaxies down to M*~10^10.2^M_{sun}_ even at z~1, allowing a reliable cluster detection at such high redshifts. We apply the CAMIRA algorithm to the HSC Wide S16A dataset covering ~232deg^2^ to construct a catalog of 1921 clusters at redshift 0.1<z<1.1 and richness N_mem_>15 that roughly corresponds to M_200m_>~10^14^h^-1^M_{sun}_. We confirm good cluster photometric redshift performance, with the bias and the scatter in {DELTA}z/(1+z) being better than 0.005 and 0.01, respectively, over most of the redshift range. We compare our cluster catalog with large X-ray cluster catalogs from the XXL and XMM-LSS (the XMM Large Scale Structure) surveys and find good correlation between richness and X-ray properties.We also study the mis-centering effect from the distribution of offsets between optical and X-ray cluster centers. We confirm the high (>0.9) completeness and purity for high-mass clusters by analyzing mock galaxy catalogs.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/143
- Title:
- HST/ACS Coma cluster survey. II.
- Short Name:
- J/ApJS/191/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Coma cluster, Abell 1656, was the target of an HST-ACS Treasury program designed for deep imaging in the F475W and F814W passbands. Although our survey was interrupted by the ACS instrument failure in early 2007, the partially completed survey still covers ~50% of the core high-density region in Coma. Observations were performed for 25 fields that extend over a wide range of cluster-centric radii (1.75Mpc or 1{deg}) with a total coverage area of 274arcmin^2^. The majority of the fields are located near the core region of Coma (19/25 pointings) with six additional fields in the southwest region of the cluster. In this paper, we present reprocessed images and SEXTRACTOR source catalogs for our survey fields, including a detailed description of the methodology used for object detection and photometry, the subtraction of bright galaxies to measure faint underlying objects, and the use of simulations to assess the photometric accuracy and completeness of our catalogs. We also use simulations to perform aperture corrections for the SEXTRACTOR Kron magnitudes based only on the measured source flux and its half-light radius. We have performed photometry for 73,000 unique objects; approximately one-half of our detections are brighter than the 10{sigma} point-source detection limit at F814W=25.8mag(AB). The slight majority of objects (60%) are unresolved or only marginally resolved by ACS. We estimate that Coma members are 5%-10% of all source detections, which consist of a large population of unresolved compact sources (primarily globular clusters but also ultra-compact dwarf galaxies) and a wide variety of extended galaxies from a cD galaxy to dwarf low surface brightness galaxies. The red sequence of Coma member galaxies has a color-magnitude relation with a constant slope and dispersion over 9mag (-21<M_I_<-13). The initial data release for the HST-ACS Coma Treasury program was made available to the public in 2008 August. The images and catalogs described in this study relate to our second data release.
- ID:
- ivo://CDS.VizieR/J/MNRAS/444/268
- Title:
- HST Frontier Fields clusters
- Short Name:
- J/MNRAS/444/268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extending over three Hubble Space Telescope (HST) cycles, the Hubble Frontier Fields (HFF) initiative constitutes the largest commitment ever of HST time to the exploration of the distant Universe via gravitational lensing by massive galaxy clusters. Here, we present models of the mass distribution in the six HFF cluster lenses, derived from a joint strong- and weak-lensing analysis anchored by a total of 88 multiple-image systems identified in existing HST data. The resulting maps of the projected mass distribution and of the gravitational magnification effectively calibrate the HFF clusters as gravitational telescopes. Allowing the computation of search areas in the source plane, these maps are provided to the community to facilitate the exploitation of forthcoming HFF data for quantitative studies of the gravitationally lensed population of background galaxies. Our models of the gravitational magnification afforded by the HFF clusters allow us to quantify the lensing-induced boost in sensitivity over blank-field observations and predict that galaxies at z>10 and as faint as m(AB)=32 will be detectable, up to 2mag fainter than the limit of the Hubble Ultra Deep Field.
- ID:
- ivo://CDS.VizieR/J/ApJ/859/38
- Title:
- HST grism obs. of CARLA galaxy cluster candidates
- Short Name:
- J/ApJ/859/38
- Date:
- 08 Mar 2022 13:56:29
- Publisher:
- CDS
- Description:
- We report spectroscopic results from our 40-orbit Hubble Space Telescope slitless grism spectroscopy program observing the 20 densest Clusters Around Radio-Loud AGN (CARLA) candidate galaxy clusters at 1.4<z<2.8. These candidate rich structures, among the richest and most distant known, were identified on the basis of [3.6]-[4.5] color from a 408hr multi-cycle Spitzer program targeting 420 distant radio-loud AGN. We report the spectroscopic confirmation of 16 distant structures at 1.4<z<2.8 associated with the targeted powerful high-redshift radio-loud AGN. We also report the serendipitous discovery and spectroscopic confirmation of seven additional structures at 0.87<z<2.12 not associated with the targeted radio-loud AGN. We find that 10^10^-10^11^M_{sun}_ member galaxies of our confirmed CARLA structures form significantly fewer stars than their field counterparts at all redshifts within 1.4<=z<=2. We also observe higher star-forming activity in the structure cores up to z=2, finding similar trends as cluster surveys at slightly lower redshifts (1.0<z<1.5). By design, our efficient strategy of obtaining just two grism orbits per field only obtains spectroscopic confirmation of emission line galaxies. Deeper spectroscopy will be required to study the population of evolved, massive galaxies in these (forming) clusters. Lacking multi-band coverage of the fields, we adopt a very conservative approach of calling all confirmations "structures," although we note that a number of features are consistent with some of them being bona fide galaxy clusters. Together this survey represents a unique and large homogenous sample of spectroscopically confirmed structures at high redshifts, potentially more than doubling the census of confirmed, massive clusters at z>1.4.
- ID:
- ivo://CDS.VizieR/J/AJ/125/478
- Title:
- HST imaging of brightest cluster galaxies
- Short Name:
- J/AJ/125/478
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used the Hubble Space Telescope Wide Field Planetary Camera 2 to obtain Iband images of the centers of 81 brightest cluster galaxies (BCGs), drawn from a volume-limited sample of nearby BCGs. The images show a rich variety of morphological features, including multiple or double nuclei, dust, stellar disks, point-source nuclei, and central surface brightness depressions. Highresolution surface brightness profiles could be inferred for 60 galaxies. Of those, 88% have well-resolved cores.
- ID:
- ivo://CDS.VizieR/J/ApJ/801/44
- Title:
- HST lensing analysis of the CLASH sample
- Short Name:
- J/ApJ/801/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a comprehensive lensing analysis in Hubble Space Telescope (HST) data of the complete Cluster Lensing And Supernova survey with Hubble cluster sample (CLASH). We identify previously undiscovered multiple images, allowing improved or first constraints on the cluster inner mass distributions and profiles. We combine these strong lensing constraints with weak lensing shape measurements within the HST field of view (FOV) to jointly constrain the mass distributions. The analysis is performed in two different common parameterizations (one adopts light-traces-mass (LTM) for both galaxies and dark matter while the other adopts an analytical, elliptical Navarro-Frenk-White (NFW) form for the dark matter) to provide a better assessment of the underlying systematics--which is most important for deep, cluster-lensing surveys, especially when studying magnified high-redshift objects. We find that the typical (median), relative systematic differences throughout the central FOV are ~40% in the (dimensionless) mass density, {kappa}, and ~20% in the magnification, {mu}. We show maps of these differences for each cluster, as well as the mass distributions, critical curves, and two-dimensional (2D)-integrated mass profiles. For the Einstein radii (z_s_=2) we find that all typically agree within 10% between the two models, and Einstein masses agree, typically, within ~15%. At larger radii, the total projected, 2D-integrated mass profiles of the two models, within r~2', differ by ~30%. Stacking the surface-density profiles of the sample from the two methods together, we obtain an average slope of dlog({Sigma})/dlog(r)~-0.64+/-0.1, in the radial range [5350]kpc. Last, we also characterize the behavior of the average magnification, surface density, and shear differences between the two models as a function of both the radius from the center and the best-fit values of these quantities.
