- ID:
- ivo://CDS.VizieR/J/AJ/128/62
- Title:
- Catalog of double nucleus disk galaxies
- Short Name:
- J/AJ/128/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled a catalog of disk galaxies that have a double nucleus, through systematic examination of existing catalogs and publications. The Catalog of Double Nucleus Disk Galaxies includes 107 objects, together with their basic data. The aim of the catalog is to provide a more systematic and homogeneous basis for the study of the relevance of galaxy interactions and minor mergers in the formation of these double nuclei. We have also investigated possible correlations between geometric and photometric parameters of the double nuclei and their host galaxies. The preliminary results indicate the presence of several significant correlations that should be considered in any theoretical scenario describing minor mergers and disk galaxy evolution
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- 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/ApJS/238/9
- Title:
- Catalog of giant radio sources known to date
- Short Name:
- J/ApJS/238/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 349 giant radio sources (GRSs including both galaxies and quasars). The database contains all giants known to date from the literature. These GRSs cover the redshift range of 0.016<z<3.22 and include radio sources of projected linear sizes larger than 0.7Mpc, which extend up to 4.7Mpc. We provide the principal parameters (i.e., exact position of the host in the sky, redshift, angular and projected linear size, red optical magnitude, radio morphology type, total radio flux density, and luminosity) for all the sources, as well as characteristics of the sample. Based on the distribution of GRSs in the sky, we identify regions where there is a paucity of giants, so that future surveys for this type of objects could concentrate primarily in these fields. From the analysis presented here, we estimate a lower limit for the expected number of GRSs as about 2000, for the resolution and sensitivity limits of FIRST, NRAO VLA Sky Survey and Sloan Digital Sky Survey surveys. Compared with earlier compilations, there is a significant increase in the number of large giants with sizes >2Mpc, as well as those at high redshifts with z>1. We discuss aspects of their evolution and suggest that these are consistent with evolutionary models.
- ID:
- ivo://CDS.VizieR/J/MNRAS/473/30
- Title:
- Catalog of Ly{alpha} emitters
- Short Name:
- J/MNRAS/473/30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a measurement of the fraction of Lyman {alpha} (Ly{alpha}) emitters (X_Ly{alpha}_) amongst HST continuum-selected galaxies at 3<z<6 with the Multi-Unit Spectroscopic Explorer (MUSE) on the VLT. Making use of the first 24 MUSE-Wide pointings in GOODS-South, each having an integration time of 1h, we detect 100Ly{alpha} emitters and find X_Ly{alpha}_>~0.5 for most of the redshift range covered, with 29 per cent of the Ly{alpha} sample exhibiting rest equivalent widths (rest-EWs)<=15{AA}. Adopting a range of rest-EW cuts (0~75{AA}), we find no evidence of a dependence of XLy{alpha} on either redshift or ultraviolet luminosity.
- 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/J/A+A/615/A167
- Title:
- Catalog of NLS1s galaxies in 6dFGS survey
- Short Name:
- J/A+A/615/A167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new accurate catalog of narrow-line Seyfert 1 galaxies (NLS1s) in the southern hemisphere from the Six-degree Field Galaxy Survey (6dFGS) final data release, which is currently the most extensive spectroscopic survey available in the southern sky whose database has not yet been systematically explored. We classified 167 sources as NLS1s based on their optical spectral properties. We derived flux-calibrated spectra for the first time that the 6dFGS does not provide. By analyzing these spectra, we obtained strong correlations between the monochromatic luminosity at 5100 Angstrom and the luminosities of H-beta and [OIII] lines. The central black hole mass and the Eddington ratio have average values of 0.86x10^7^M_{sun}_ and 0.96L_Edd_ respectively, which are typical values for NLS1s. In the sample, 23 (13.8%) NLS1s were detected at radio frequencies, and 12 (7.0%) of them are radio-loud. Our results confirmed that radio-loud sources tend to have higher redshift, a more massive black hole, and higher radio and optical luminosities than radio-quiet sources.
- 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/ApJS/219/1
- Title:
- Catalog of Type-1 AGNs from SDSS-DR7
- Short Name:
- J/ApJS/219/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have recently identified a substantial number of type 1 active galactic nuclei (AGNs) featuring weak broad-line regions (BLRs) at z<0.2 from detailed analysis of galaxy spectra in the Sloan Digital Sky Survey Data Release 7. These objects predominantly show a stellar continuum but also a broad H{alpha} emission line, indicating the presence of a low-luminosity AGN oriented so that we are viewing the central engine directly without significant obscuration. These accreting black holes have previously eluded detection due to their weak nature. The newly discovered BLR AGNs have increased the number of known type 1 AGNs by 49%. Some of these new BLR AGNs were detected with the Chandra X-ray Observatory, and their X-ray properties confirm that they are indeed type 1 AGNs. Based on our new and more complete catalog of type 1 AGNs, we derived the type 1 fraction of AGNs as a function of [OIII]{lambda}5007 emission luminosity and explored the possible dilution effect on obscured AGNs due to star formation. The new type 1 AGN fraction shows much more complex behavior with respect to black hole mass and bolometric luminosity than has been suggested previously by the existing receding torus model. The type 1 AGN fraction is sensitive to both of these factors, and there seems to be a sweet spot (ridge) in the diagram of black hole mass and bolometric luminosity. Furthermore, we present the possibility that the Eddington ratio plays a role in determining opening angles.
- ID:
- ivo://CDS.VizieR/J/ApJ/723/737
- Title:
- Catalog of variability selected AGNs in GOODS
- Short Name:
- J/ApJ/723/737
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Variability is a property shared by practically all active galactic nuclei (AGNs). This makes variability selection a possible technique for identifying AGNs. Given that variability selection makes no prior assumption about spectral properties, it is a powerful technique for detecting both low-luminosity AGNs in which the host galaxy emission is dominating and AGNs with unusual spectral properties. In this paper, we will discuss and test different statistical methods for the detection of variability in sparsely sampled data that allow full control over the false positive rates. We will apply these methods to the GOODS North and South fields and present a catalog of variable sources in the z band in both GOODS fields. Out of the 11 931 objects checked, we find 155 variable sources at a significance level of 99.9%, corresponding to about 1.3% of all objects. After rejection of stars and supernovae, 139 variability-selected AGNs remain. Their magnitudes reach down as faint as 25.5mag in z. Spectroscopic redshifts are available for 22 of the variability-selected AGNs, ranging from 0.046 to 3.7. The absolute magnitudes in the rest-frame z band range from ~-18 to -24, reaching substantially fainter than the typical luminosities probed by traditional X-ray and spectroscopic AGN selection in these fields. Therefore, this is a powerful technique for future exploration of the evolution of the faint end of the AGN luminosity function up to high redshifts.