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- ID:
- ivo://CDS.VizieR/J/AZh/87/795
- Title:
- Catalog of galaxies in and around A1367
- Short Name:
- J/AZh/87/795
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of galaxies in and around the cluster A1367, together with the results of a spectroscopic study of eight faint galaxies projected onto the central part of the cluster. The observations were carried out with the Boller and Chivens spectrograph of the 2m telescope of the Guillermo Haro Observatory (Cananea, Mexico). Redshifts of eight galaxies were derived from both emission and absorption lines; the redshift for one of these, derived from Halpha, SII, OIII, and Hbeta emission lines, is z=0.015. The spectrum of this galaxy displays no absorption lines at z=0.026, testifying that it is located between the observer and A1367.
- ID:
- ivo://CDS.VizieR/J/ApJ/751/50
- Title:
- Catalog of galaxy groups from DEEP2 Redshift Survey
- Short Name:
- J/ApJ/751/50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a public catalog of galaxy groups constructed from the spectroscopic sample of galaxies in the fourth data release from the Deep Extragalactic Evolutionary Probe 2 (DEEP2) Galaxy Redshift Survey, including the Extended Groth Strip (EGS). The catalog contains 1165 groups with two or more members in the EGS over the redshift range 0<z<1.5 and 1295 groups at z>0.6 in the rest of DEEP2. 25% of EGS galaxies and 14% of high-z DEEP2 galaxies are assigned to galaxy groups. The groups were detected using the Voronoi-Delaunay method (VDM) after it has been optimized on mock DEEP2 catalogs following similar methods to those employed in Gerke et al (2005, J/ApJ/625/6). In the optimization effort, we have taken particular care to ensure that the mock catalogs resemble the data as closely as possible, and we have fine-tuned our methods separately on mocks constructed for the EGS and the rest of DEEP2. We have also probed the effect of the assumed cosmology on our inferred group-finding efficiency by performing our optimization on three different mock catalogs with different background cosmologies, finding large differences in the group-finding success we can achieve for these different mocks. Using the mock catalog whose background cosmology is most consistent with current data, we estimate that the DEEP2 group catalog is 72% complete and 61% pure (74% and 67% for the EGS) and that the group finder correctly classifies 70% of galaxies that truly belong to groups, with an additional 46% of interloper galaxies contaminating the catalog (66% and 43% for the EGS). We also confirm that the VDM catalog reconstructs the abundance of galaxy groups with velocity dispersions above ~300 km/s to an accuracy better than the sample variance, and this successful reconstruction is not strongly dependent on cosmology.
- ID:
- ivo://CDS.VizieR/J/ApJS/157/228
- Title:
- Catalog of galaxy morphology in four clusters
- Short Name:
- J/ApJS/157/228
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Hubble Space Telescope (HST) imaging of four rich, X-ray-luminous, galaxy clusters (0.33<z<0.83) is used to produce quantitative morphological measurements for galaxies in their fields. Catalogs of these measurements are presented for 1642 galaxies brighter than F814W(AB)=23.0. Galaxy luminosity profiles are fitted with three models: exponential disk, de Vaucouleurs bulge, and a disk-plus-bulge hybrid model. The best fit is selected and produces a quantitative assessment of the morphology of each galaxy: the principal parameters derived being B/T, the ratio of bulge to total luminosity, the scale lengths and half-light radii, axial ratios, position angles, and surface brightnesses of each component. Cluster membership is determined using a statistical correction for field galaxy contamination, and a mass normalization factor (mass within boundaries of the observed fields) is derived for each cluster. Morphological classes are defined using B/T: disk galaxies have 0<=B/T<=0.4, intermediate galaxies 0.4<B/T<0.8, and bulge-dominated galaxies have 0.8<=B/T<=1.
- ID:
- ivo://CDS.VizieR/J/other/JAD/12.1
- Title:
- Catalog of galaxy structures based on the MRSS
- Short Name:
- J/other/JAD/12.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of galaxy structures (groups and clusters) found in an area of 5000 square degrees in the southern hemisphere. The catalogue, which we call the PF Catalogue, was created by making use of galaxy positions and magnitudes given in the Muenster Red Sky Survey (MRSS, 2003JAD.....9....1U). We applied an automated procedure for structure finding, involving the Voronoi tessellation. The completeness limit for galaxies in the MRSS is r_F_=18.3m. Therefore, the present version of the PF Catalogue is based on galaxies brighter than this limit. In order to be included in the PF Catalogue, a structure must have at least 10 members in a magnitude range m_3_, m_3_+3^m^. We found 6188 structures which are listed in the present catalogue. The PF Catalogue contains positions, radii, areas, number of galaxies within the magnitude limit m_3_, m_3_+3^m^, a number estimation of background galaxies; ellipticity and position angle for each structure, as well as the magnitudes of the first, the third and the tenth galaxies in a structure, taken from the MRSS.
- ID:
- ivo://CDS.VizieR/J/AJ/147/106
- Title:
- Catalog of member galaxies in A2319
- Short Name:
- J/AJ/147/106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asymmetric X-ray emission and a powerful cluster-scale radio halo indicate that A2319 is a merging cluster of galaxies. This paper presents our multicolor photometry for A2319 with 15 optical intermediate filters in the Beijing-Arizona-Taiwan-Connecticut (BATC) system. There are 142 galaxies with known spectroscopic redshifts within the viewing field of 58'x58' centered on this rich cluster, including 128 member galaxies (called sample I). A large velocity dispersion in the rest frame, 1622_-70_^+91^km/s, suggests merger dynamics in A2319. The contour map of projected density and localized velocity structure confirm the so-called A2319B substructure, at ~10' northwest to the main concentration A2319A. The spectral energy distributions (SEDs) of more than 30000 sources are obtained in our BATC photometry down to V~20mag. A u-band (~3551{AA}) image with better seeing and spatial resolution, obtained with the Bok 2.3m telescope at Kitt Peak, is taken to make star-galaxy separation and distinguish the overlapping contamination in the BATC aperture photometry. With color-color diagrams and photometric redshift technique, 233 galaxies brighter than h_BATC_=19.0 are newly selected as member candidates after an exclusion of false candidates with contaminated BATC SEDs by eyeball-checking the u-band Bok image. The early-type galaxies are found to follow a tight color-magnitude correlation. Based on sample I and the enlarged sample of member galaxies (called sample II), subcluster A2319B is confirmed. The star formation properties of cluster galaxies are derived with the evolutionary synthesis model, PEGASE, assuming a Salpeter initial mass function and an exponentially decreasing star formation rate (SFR). A strong environmental effect on star formation histories is found in the manner that galaxies in the sparse regions have various star formation histories, while galaxies in the dense regions are found to have shorter SFR time scales, older stellar ages, and higher interstellar medium metallicities. For the merging cluster A2319, local surface density is a better environmental indicator rather than the cluster-centric distance. Compared with the well-relaxed cluster A2589, a higher fraction of star-forming galaxies is found in A2319, indicating that the galaxy-scale turbulence stimulated by the subcluster merger might have played a role in triggering the star formation activity.
- ID:
- ivo://CDS.VizieR/VII/96
- Title:
- Catalog of morphological properties of Abell clusters
- Short Name:
- VII/96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog is presented which contains Rood-Sastry (1971, hereafter RS) morphological types for all 2712 Abell clusters.
- ID:
- ivo://CDS.VizieR/J/ApJ/619/193
- Title:
- Catalog of nearby cluster galaxy photometry
- Short Name:
- J/ApJ/619/193
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed (U-V) color-magnitude relation (CMR) analysis for three local (z<0.06) clusters of galaxies. From square-degree imaging of the Abell clusters A85, A496, and A754, we select 637 galaxies down to L~0.1L_V_^*^ with spectroscopic membership, which minimizes uncertain field contamination corrections.
- ID:
- ivo://CDS.VizieR/J/ApJ/502/558
- Title:
- Catalog of ROSAT galaxy clusters
- Short Name:
- J/ApJ/502/558
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 203 clusters of galaxies serendipitously detected in 647 ROSAT PSPC high Galactic latitude pointings covering 158deg^2^. This is one of the largest X-ray-selected cluster samples, comparable in size only to the ROSAT All-Sky Survey sample of nearby clusters (Ebeling et al., 1997ApJ...479L.101E). We detect clusters in the inner 175 of the ROSAT PSPC field of view using the spatial extent of their X-ray emission. Fluxes of detected clusters range from 1.6x10^-14^ to 8x10^-12^ergs/s/cm^2^ in the 0.52keV energy band. X-ray luminosities range from 10^42^ergs/s, corresponding to very poor groups, to ~5x10^44^ergs/s, corresponding to rich clusters. The cluster redshifts range from z=0.015 to z>0.5. The catalog lists X-ray fluxes, core radii, and spectroscopic redshifts for 73 clusters and photometric redshifts for the remainder.
- ID:
- ivo://CDS.VizieR/J/A+A/566/A140
- Title:
- Catalog of XMM X-ray galaxy groups
- Short Name:
- J/A+A/566/A140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 129 X-ray galaxy groups, covering a redshift range 0.04<z<1.23, selected in the ~3deg^2^ part of the CFHTLS W1 field overlapping XMM observations performed under the XMM-LSS project. We carry out a statistical study of the redshift evolution out to redshift one of the magnitude gap between the first and the second brightest cluster galaxies of a well defined mass-selected group sample. We find that the slope of the relation between the fraction of groups and the magnitude gap steepens with redshift, indicating a larger fraction of fossil groups at lower redshifts. We find that 22.2+/-6% of our groups at z<=0.6 are fossil groups. We compare our results with the predictions of three semi-analytic models based on the Millennium simulation. The intercept of the relation between the magnitude of the brightest galaxy and the value of magnitude gap becomes brighter with increasing redshift. This trend is steeper than the model predictions which we attribute to the younger stellar age of the observed brightest cluster galaxies. This trend argues in favor of stronger evolution of the feedback from active galactic nuclei at z<1 compared to the models. The slope of the relation between the magnitude of the brightest cluster galaxy and the value of the gap does not evolve with redshift and is well reproduced by the models, indicating that the tidal galaxy stripping, put forward as an explanation of the occurrence of the magnitude gap, is both a dominant mechanism and sufficiently well modeled.
