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), the authors identify 39,716 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 > 2 x 10¹⁴ M_sun, where M_200 is the total mass within the radius in which the mean mass density is 200 times the critical cosmic mass density) clusters of z <= 0.42. The false detection rate is ~5%. The authors 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 the clusters. Cluster mass is related to the richness and summed luminosity with M_200 ~ R^{(1.90+/-0.04)} and M_200 ~ L_r^{(1.64+/-0.03)}, respectively. In addition, 790 new candidate X-ray clusters are found by cross-identification of these clusters with the source list of the ROSAT X-ray All-Sky Survey. This table was created by the HEASARC in August 2009 based on electronic versions of Tables 1 and 2 from the paper which were obtained from the Astrophysical Journal web site. This is a service provided by NASA HEASARC .

The Center for Astrophysics (CfA) Redshift Survey South Galactic Cap (CFA2S) Catalog contains redshifts for a sample of about 4300 galaxies with blue (Zwicky B(0) type) magnitude <= 15.5 covering the range from 20 h to 4h in right ascension and from -2.5 deg to 90 deg in declination. This sample is complete for all galaxies in the merge of the Zwicky et al. and Nilson catalogs in the south Galactic cap. Redshifts for 2964 of these were measured as part of the second CfA Redshift Survey. The data reveal large voids in the foreground and background of the Perseus-Pisces Supercluster. The largest of these voids lies at a mean velocity ~ 8000km/s, has diameter of ~ 5000km/s, and is enclosed by a complex of dense structures. The large structure known as the Perseus-Pisces Supercluster forms the near side of this complex. On the far side of this large void, at a mean velocity of ~ 12000km/s, there is another coherent dense wall. The structures in this survey support the view that galaxies generally lie on surfaces surrounding or nearly surrounding low-density regions or voids. This table was created by the HEASARC in March 2005 based on CDS table J/ApJS/121/287/cfa2s.dat.gz This is a service provided by NASA HEASARC .

This table is based on the results of the 2MASS Redshift Survey (2MRS), a ten-year project to map the full three-dimensional distribution of galaxies in the nearby universe. The Two Micron All Sky Survey (2MASS) was completed in 2003 and its final data products, including an extended source catalog (XSC), are available online. The 2MASS XSC contains nearly a million galaxies with K_s <= 13.5 mag and is essentially complete and mostly unaffected by interstellar extinction and stellar confusion down to a galactic latitude of |b| = 5 degrees for bright galaxies. Near-infrared wavelengths are sensitive to the old stellar populations that dominate galaxy masses, making 2MASS an excellent starting point to study the distribution of matter in the nearby universe. The authors selected a sample of 44,599 2MASS galaxies with K_s <= 11.75 mag and |b| >= 5 degrees (>= 8 degrees toward the Galactic bulge) as the input catalog for their survey. They obtained spectroscopic observations for 11,000 galaxies and used previously obtained velocities for the remainder of the sample to generate a redshift catalog that is 97.6% complete to well-defined limits and covers 91% of the sky. This provides an unprecedented census of galaxy (baryonic mass) concentrations within 300 Mpc. Earlier versions of their survey have been used in a number of publications that have studied the bulk motion of the Local Group, mapped the density and peculiar velocity fields out to 50 h^-1 Mpc, detected galaxy groups, and estimated the values of several cosmological parameters. Additionally, the authors present morphological types for a nearly complete sub-sample of 20,860 galaxies with K_s <= 11.25 mag and |b| >= 10 degrees. The authors initially selected 45,086 sources which met the following criteria:

 Ks <= 11.75 mag and detected at H, E(B - V) <= 1 mag, |b| >= 5 degrees for 30 degrees < l < 330 degrees, |b| >= 8 degrees otherwise. 

They rejected 324 sources of galactic origin (multiple stars, planetary nebulae, and H II regions) or pieces of galaxies detected as separate sources by the 2MASS pipeline. Additionally, they flagged 314 bona fide galaxies with compromised photometry for reprocessing at a future date. Some of these galaxies have bright stars very close to their nuclei which were not detected by the pipeline. Others are in regions of high stellar density and their center positions and/or isophotal radii have been incorrectly measured by the pipeline. Lastly, some are close pairs or multiples but the pipeline only identified a single object. A detailed explanation of the steps taken to reject and reprocess the flagged galaxies is given in the Appendix of the reference paper. In summary, the final input catalog contained here has 44,599 entries (plotted using black symbols in Figure 1 of the reference paper). In this table, redshifts for 43,533 of the selected galaxies, or 97.6% of the sample, are presented. This table was created by the HEASARC in April 2012 based on an electronic version of Table 3 of the reference paper which was obtained from the ApJS website. This is a service provided by NASA HEASARC .

In their paper, the authors release accurate photometric redshifts for 1692 counterparts to Chandra sources in the central square degree of the Cosmic Evolution Survey (COSMOS) field. The availability of a large training set of spectroscopic redshifts that extends to faint magnitudes enabled photometric redshifts comparable to the highest quality results presently available for normal galaxies. The authors demonstrate that morphologically extended, faint X-ray sources without optical variability are more accurately described by a library of normal galaxies (corrected for emission lines) than by active galactic nucleus (AGN) dominated templates, even if these sources have AGNlike X-ray luminosities. Preselecting the library on the bases of the source properties allowed them to reach an accuracy sigma[Delta-z/(1+Z_spec)] ~ 0.015 with a fraction of outliers of 5.8% for the entire Chandra-COSMOS sample. In addition, in this study the authors released revised photometric redshifts for the 1735 optical counterparts of the XMM-detected sources over the entire 2 deg² of COSMOS (these sources are listed in the HEASARC table XMMCPHOTZ). For 248 sources, their updated photometric redshift differs from the previous release by Delta-z > 0.2. These changes are predominantly due to the inclusion of newly available deep H-band^ photometry (H_AB = 24 mag). The authors illustrate once again the importance of a spectroscopic training sample and how an assumption about the nature of a source together, with the number and the depth of the available bands, influences the accuracy of the photometric redshifts determined for AGN. These considerations should be kept in mind when defining the observational strategies of upcoming large surveys targeting AGNs, such as eROSITA at X-ray energies and the Australian Square Kilometre Array Pathfinder Evolutionary Map of the Universe in the radio band. This table contains the photometric redshifts and related quantities for 1694 (note that there appears to be 2 more sources than the above-quoted abstract states) Chandra sources in the central square degree of the COSMOS field. Notice that in the original as-published paper no positional information was provided. The HEASARC has assumed that the source numbers used in the present catalog are in the same source numbering scheme as used by Elvis et al. (2009, ApJS, 184, 158, the Chandra COSMOS Survey Point Source Catalog, available at the HEASARC as the CCOSMOSCAT table) and thus obtained the positions and (position-based) names corresponding to these sources. This table was created by the HEASARC in November 2011 based on an electronic version of Table 4 from the reference paper which was obtained from the ApJ website. This is a service provided by NASA HEASARC .

This table contains the X-ray point-source catalog produced from the Chandra Advanced CCD Imaging Spectrometer (ACIS-I) observations of the combined ~3.2 deg² DEEP2 (XDEEP2) survey fields, which consist of four ~ 0.7 - 1.1 deg² fields. The combined total exposures across all four XDEEP2 fields range from ~ 10 ks to 1.1 Ms. The authors detect X-ray point sources in both the individual ACIS-I observations and the overlapping regions in the merged (stacked) images. They find a total of 2976 unique X-ray sources within the survey area with an expected false-source contamination of ~ 30 sources (<~ 1%). In their paper, the authors present the combined log N-log S distribution of sources detected across the XDEEP2 survey fields and find good agreement with the Extended Chandra Deep Field and Chandra-COSMOS fields to f_(X,0.5-2keV)_ ~ 2 x 10^-16 erg cm^-1 s^-1. Given the large survey area of XDEEP2, they additionally place relatively strong constraints on the log N-log S distribution at high fluxes (f_(X,0.5-2keV) ~ 3 x 10^-14 erg cm^-1 s^-1), and find a small systematic offset (a factor ~ 1.5) toward lower source numbers in this regime, when compared to smaller area surveys. The number counts observed in XDEEP2 are in close agreement with those predicted by X-ray background synthesis models. Additionally, the authors present a Bayesian-style method for associating the X-ray sources with optical photometric counterparts in the DEEP2 catalog (complete to R_AB < 25.2) and find that 2126 (~ 71.4% +/- 2.8%) of the 2976 X-ray sources presented here have a secure optical counterpart with a <~ 6% contamination fraction. The present table provides the DEEP2 optical source properties (e.g., magnitude, redshift) as part of the X-ray-optical counterpart catalog. This table was created by the HEASARC in October 2012 based on electronic versions of Tables 5 and 7 from the reference paper which were obtained from the ApJS web site. This is a service provided by NASA HEASARC .

COSMOS is an astronomical survey designed to probe the formation and evolution of galaxies as a function of cosmic time (redshift) and large scale structural environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes (Hubble, Spitzer, GALEX, XMM, Chandra) and a number of large ground based telescopes (Subaru, VLA, ESO-VLT, UKIRT, NOAO, CFHT, and others). Over 2 million galaxies are detected, spanning 75% of the age of the universe.

In their paper, the authors release accurate photometric redshifts for 1692 counterparts to Chandra sources in the central square degree of the Cosmic Evolution Survey (COSMOS) field. The availability of a large training set of spectroscopic redshifts that extends to faint magnitudes enabled photometric redshifts comparable to the highest quality results presently available for normal galaxies. The authors demonstrate that morphologically extended, faint X-ray sources without optical variability are more accurately described by a library of normal galaxies (corrected for emission lines) than by active galactic nucleus (AGN) dominated templates, even if these sources have AGNlike X-ray luminosities. Preselecting the library on the bases of the source properties allowed them to reach an accuracy sigma[Delta-z/(1+Z_spec)] ~ 0.015 with a fraction of outliers of 5.8% for the entire Chandra-COSMOS sample. These Chandra sources are not contained in this table but are available in the HEASARC table CCOSMPHOTZ). In addition, in this study the authors released revised photometric redshifts for the 1735 optical counterparts of the XMM-detected sources over the entire 2 deg² of COSMOS, and these are the sources listed in the present table. For 248 sources, their updated photometric redshift differs from the previous release by Delta-z > 0.2. These changes are predominantly due to the inclusion of newly available deep H-band^ photometry (H_AB = 24 mag). The authors illustrate once again the importance of a spectroscopic training sample and how an assumption about the nature of a source together, with the number and the depth of the available bands, influences the accuracy of the photometric redshifts determined for AGN. These considerations should be kept in mind when defining the observational strategies of upcoming large surveys targeting AGNs, such as eROSITA at X-ray energies and the Australian Square Kilometre Array Pathfinder Evolutionary Map of the Universe in the radio band. This table contains the photometric redshifts and related quantities for 1735 XMM-Newton sources over the entire 2 square degrees of the COSMOS field. Notice that in the original as-published paper no positional information was provided. The HEASARC has assumed that the source numbers used in the present catalog are in the same source numbering scheme as used by Cappelluti et al. (2009, A&A, 497, 635, the XMM-Newton Wide-Field Survey in the COSMOS Field Point-like X-ray Source Catalog, available at the HEASARC as the XMMCOSMOS table) and thus obtained the positions and (position-based) names corresponding to these X-ray sources from the latter. This table was created by the HEASARC in November 2011 based on an electronic version of Table 5 from the reference paper which was obtained from the ApJ website. This is a service provided by NASA HEASARC .