- ID:
- ivo://CDS.VizieR/J/A+A/445/819
- Title:
- Systems of galaxies in Shapley supercluster
- Short Name:
- J/A+A/445/819
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on the largest compilation of galaxies with redshift in the region of the Shapley Supercluster (Proust et al., 2004 in prep., 2006A&A...447..133P), we identified 122 galaxy systems, 60 of which are new systems. Using the SuperCOSMOS catalogue, we have assigned b_j_ magnitudes to each galaxy in our compilation. The sample of galaxy systems was used to estimate the mass function of systems in the range 10^13^ to 10^15^M_{sun}/h^-1^. We computed a lower value to the total mass in the region of the Shapley Supercluster with this mass function. Using 15 mock catalogues we derived the mean mass that these kinds of systems have before comparing it with that obtained from the real data.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/461/248
- Title:
- 44 SZ-selected galaxy clusters ACT observations
- Short Name:
- J/MNRAS/461/248
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present galaxy velocity dispersions and dynamical mass estimates for 44 galaxy clusters selected via the Sunyaev-Zel'dovich (SZ) effect by the Atacama Cosmology Telescope. Dynamical masses for 18 clusters are reported here for the first time. Using N-body simulations, we model the different observing strategies used to measure the velocity dispersions and account for systematic effects resulting from these strategies. We find that the galaxy velocity distributions may be treated as isotropic, and that an aperture correction of up to 7 per cent in the velocity dispersion is required if the spectroscopic galaxy sample is sufficiently concentrated towards the cluster centre. Accounting for the radial profile of the velocity dispersion in simulations enables consistent dynamical mass estimates regardless of the observing strategy. Cluster masses M_200_ are in the range (1-15)x10^14^M_{sun}_. Comparing with masses estimated from the SZ distortion assuming a gas pressure profile derived from X-ray observations gives a mean SZ-to-dynamical mass ratio of 1.10+/-0.13, but there is an additional 0.14 systematic uncertainty due to the unknown velocity bias; the statistical uncertainty is dominated by the scatter in the mass-velocity dispersion scaling relation. This ratio is consistent with previous determinations at these mass scales.
1033. The A3528 complex
- ID:
- ivo://CDS.VizieR/J/MNRAS/320/387
- Title:
- The A3528 complex
- Short Name:
- J/MNRAS/320/387
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a redshift survey of galaxies in the A3528 complex, a chain of interacting clusters in the core of the Shapley Concentration. The spectroscopic observations were performed at the 3.6-m ESO telescope at La Silla, equipped with the OPTOPUS multifibre spectrograph, on the nights of 1991 March 8-9 (for the Field 10) and from 1993 February 23-27.
- ID:
- ivo://CDS.VizieR/J/AJ/157/81
- Title:
- The Arecibo PPS Survey. I. Harvesting ALFALFA
- Short Name:
- J/AJ/157/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a multi-objective campaign of targeted 21 cm H I line observations of sources selected from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey and galaxies identified by their morphological and photometric properties in the Sloan Digital Sky Survey. The aims of this program have been (1) to confirm the reality of some ALFALFA sources whose enigmatic nature suggest additional multiwavelength observations; (2) to probe the low signal-to-noise ratio (S/N) regime, below the ALFALFA reliability limit; and (3) to explore the feasibility of using optical morphology, color, and surface brightness to identify gas-rich objects in the region of the Pisces-Perseus Supercluster (PPS) whose H I fluxes are below the ALFALFA sensitivity limit at that distance. As expected, the reliability of ALFALFA detections depends strongly on the S/N of the H I line signal and its coincidence with a probable stellar counterpart identified by its optical properties, suggestive of ongoing star formation. The identification of low-mass, star-forming populations enables targeted H I line observations to detect galaxies with H I line fluxes below the ALFALFA sensitivity limits in fixed local volumes (D<100 Mpc). The method explored here serves as the basis for extending the sample of gas-bearing objects as part of the ongoing Arecibo Pisces-Perseus Supercluster Survey (APPSS).
- ID:
- ivo://CDS.VizieR/J/ApJ/746/178
- Title:
- The augmented maxBCG cluster catalog
- Short Name:
- J/ApJ/746/178
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Reducing the scatter between cluster mass and optical richness is a key goal for cluster cosmology from photometric catalogs. We consider various modifications to the red-sequence-matched filter richness estimator of Rozo et al. (Paper I, 2009ApJ...703..601R) implemented on the maxBCG cluster catalog and evaluate the impact of these changes on the scatter in X-ray luminosity (L_X_) at fixed richness, using L_X_ from the ROSAT All-Sky Catalog as the best mass proxy available for the large area required. Most significantly, we find that deeper luminosity cuts can reduce the recovered scatter, finding that {sigma}_lnLx|{lambda}_=0.63+/-0.02 for clusters with M_500c_>~1.6x10^14^h^-1^_70_M_{sun}_. The corresponding scatter in mass at fixed richness is {sigma}_lnM|{lambda}_~0.2-0.3 depending on the richness, comparable to that for total X-ray luminosity. We find that including blue galaxies in the richness estimate increases the scatter, as does weighting galaxies by their optical luminosity. We further demonstrate that our richness estimator is very robust. Specifically, the filter employed when estimating richness can be calibrated directly from the data, without requiring a priori calibrations of the red sequence. We also demonstrate that the recovered richness is robust to up to 50% uncertainties in the galaxy background, as well as to the choice of photometric filter employed, so long as the filters span the 4000{AA} break of red-sequence galaxies. Consequently, our richness estimator can be used to compare richness estimates of different clusters, even if they do not share the same photometric data. Appendix A includes "easy-bake" instructions for implementing our optimal richness estimator, and we are releasing an implementation of the code that works with Sloan Digital Sky Survey data, as well as an augmented maxBCG catalog with the {lambda} richness measured for each cluster.
1036. The BAX Database
- ID:
- ivo://CDS.VizieR/B/bax
- Title:
- The BAX Database
- Short Name:
- B/bax
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present BAX, Base de Donnees Amas de Galaxies X (http://bax.ast.obs-mip.fr), a multi-wavelength database dedicated to X-ray clusters and groups of galaxies allowing detailed information retrieval. BAX is designed to support astronomical research by providing access to published measurements of the main physical quantities and to the related bibliographic references: basic data stored in the database are cluster/group identifiers, equatorial coordinates, redshift, flux, X-ray luminosity (in the ROSAT band) and temperature, and links to additional linked parameters (in X-rays, such as spatial profile parameters, as well as SZ parameters of the hot gas, lensing measurements, and data at other wavelengths, such as optical and radio). The clusters and groups in BAX can be queried by the basic parameters as well as the linked parameters or combinations of these. We expect BAX to become an important tool for the astronomical community. BAX will optimize various aspects of the scientific analysis of X-ray clusters and groups of galaxies, from proposal planning to data collection, interpretation and publication, from both ground based facilities like MEGACAM (CFHT), VIRMOS (VLT) and space missions like XMM-Newton, Chandra and Planck.
- ID:
- ivo://CDS.VizieR/J/A+AS/124/1
- Title:
- The Centaurus Cluster Catalogue
- Short Name:
- J/A+AS/124/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The central region of the Centaurus cluster was surveyed on a film copy of a high-resolution photographic Las Campanas duPont plate. A large number of cluster galaxy candidates were identified down to a limiting magnitude of 21.5 in B. Between cluster members and background objects were distinguished by applying morphological criteria. Following the morphological classification of each member, the images of all 296 cluster galaxies on a SERC deep-blue sky survey plate were digitized, processed and analysed with the image processing package MIDAS. We established total apparent B-magnitude and other structure parameters for each cluster galaxy which are listed in the Centaurus Cluster Catalogue.
- ID:
- ivo://CDS.VizieR/J/A+AS/134/59
- Title:
- The central Fornax Cluster. I. Galaxy photometry
- Short Name:
- J/A+AS/134/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, a photometric catalog is presented of V and I photometry of galaxies in the central regions of the Fornax galaxy cluster. Our 11 CCD fields cover 0.17 square degrees in total. The limiting surface brightness is around 24mag/arcsec^2^, similar to that of Ferguson's (1989, Cat. <VII/180>) catalog, whereas our limiting total magnitude is around V=22mag, about two magnitudes fainter. The photometric properties of more than 870 objects are presented as a catalog (Appendix A). The properties and fit parameters of the surface brightness profiles for a sub-sample are presented in a second catalog (Appendix B). Four new dwarf galaxies are added to Ferguson's catalog. However, we confirm that the dwarf galaxies in Fornax follow a similar surface brightness -- magnitude relation as the Local Group dwarfs. They also follow the color (metallicity) -- magnitude relation seen in other galaxy clusters. A formerly suspected excess of dwarf galaxies surrounding the central giant cD galaxy NGC 1399 can be explained by the superposition of a background cluster at z=0.11 (Hilker et al. 1998, Cat. <J/A+AS/134/75>, Paper II in this series).
1039. The 400d cluster Survey
- ID:
- ivo://CDS.VizieR/J/ApJS/172/561
- Title:
- The 400d cluster Survey
- Short Name:
- J/ApJS/172/561
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of galaxy clusters detected in a new ROSAT PSPC survey. The survey is optimized to sample, at high redshifts, the mass range corresponding to T>5keV clusters at z=0. Technically, our survey is the extension of the 160 square degree survey (160d, Cat. J/ApJ/502/558). We use the same detection algorithm, thus preserving high quality of the resulting sample; the main difference is a significant increase in sky coverage. The new survey covers 397deg^2^ and is based on 1610 high Galactic latitude ROSAT PSPC pointings, virtually all pointed ROSAT data suitable for the detection of distant clusters. The search volume for X-ray luminous clusters within z<1 exceeds that of the entire local universe (z<0.1). We detected 287 extended X-ray sources with fluxes f>1.4x10^-13^ergs/s/cm^2^ in the 0.5-2keV energy band, of which 266 (93%) are optically confirmed as galaxy clusters, groups or individual elliptical galaxies.
1040. The ENACS Catalogue. V.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/399
- Title:
- The ENACS Catalogue. V.
- Short Name:
- J/A+AS/129/399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalogue resulting from the ESO Nearby Abell Cluster Survey (the ENACS), which contains redshifts and magnitudes for 5634 galaxies in the directions of 107 rich, nearby southern Abell cluster candidates. We describe the contents of the catalogue and discuss the results of a comparison between the ENACS catalogue and the COSMOS Galaxy Catalogue. When cross-correlating the two catalogues we find that, at least in the areas of the ENACS clusters, the completeness of the COSMOS catalogue is somewhat lower than was estimated previously for the carefully analyzed and well-calibrated part of the COSMOS catalogue known as the Edinburgh-Durham Southern Galaxy Survey (EDSGC). The galaxy positions in the COSMOS and ENACS catalogues are found to be on the same system to within about one arcsecond. For the clusters for which the photometry in the ENACS and COSMOS catalogues is based on the same survey plates, the two magnitude scales agree very well. We confirm that the photometric calibration in the EDSGC subset of the COSMOS catalogue is of higher quality than in the EDSGC complement. The ENACS galaxy samples are unbiased subsets of the COSMOS catalogue as far as the projected galaxy distribution is concerned, except in only a few cases. We summarize how the ENACS galaxy samples are subsets of the COSMOS catalogues in the ENACS apertures, with respect to magnitude. For the ENACS catalogue as a whole, we describe the apparent incompleteness at faint magnitudes and towards higher redshifts. Finally, we provide some detailed information about the ENACS catalogue that is essential for its proper statistical use and we summarize some facts that must be remembered when selecting subsets of galaxies from it. Objects:
