- ID:
- ivo://CDS.VizieR/J/ApJS/164/334
- Title:
- ACS Virgo Cluster Survey. VI
- Short Name:
- J/ApJS/164/334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a detailed analysis of the morphology, isophotal parameters, and surface brightness profiles for 100 early-type members of the Virgo Cluster, from dwarfs (M_B_=-15.1mag) to giants (M_B_=-21.8mag), imaged in the g and z passbands using the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope.
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- ID:
- ivo://CDS.VizieR/J/ApJ/655/144
- Title:
- ACS Virgo Cluster Survey. XIII.
- Short Name:
- J/ApJ/655/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ACS Virgo Cluster Survey consists of HST-ACS Advance Camera for Surveys) imaging for 100 early-type galaxies in the Virgo Cluster, observed in the F475W (~SDSS g) and F850LP (~SDSS z) filters. We derive distances for 84 of these galaxies using the method of surface brightness fluctuations (SBFs), present the SBF distance catalog, and use this database to examine the three-dimensional distribution of early-type galaxies in the Virgo Cluster. The SBF distance moduli have a mean (random) measurement error of 0.07mag (0.5Mpc), or roughly 3 times better than previous SBF measurements for Virgo Cluster galaxies. Five galaxies lie at a distance of d~23Mpc and are members of the W' cloud. The remaining 79 galaxies have a narrow distribution around our adopted distance of <d>=16.5+/-0.1 (random mean error) +/-1.1Mpc (systematic). The rms distance scatter of this sample is {sigma}(d)=0.6+/-0.1Mpc, with little or no dependence on morphological type or luminosity class (i.e., 0.7+/-0.1 and 0.5+/-0.1Mpc for the giants and dwarfs, respectively). The back-to-front depth of the cluster measured from our sample of early-type galaxies is 2.4+/-0.4Mpc (i.e., +/-2{sigma} of the intrinsic distance distribution). The M87 (cluster A) and M49 (cluster B) subclusters are found to lie at distances of 16.7+/-0.2 and 16.4+/-0.2Mpc, respectively. There may be a third subcluster associated with M86. A weak correlation between velocity and line-of-sight distance may be a faint echo of the cluster velocity distribution not having yet completely virialized. In three dimensions, Virgo's early-type galaxies appear to define a slightly triaxial distribution, with axis ratios of (1:0.7:0.5). The principal axis of the best-fit ellipsoid is inclined ~20{deg}-40{deg} from the line of sight, while the galaxies belonging to the W' cloud lie on an axis inclined by ~10{deg}-15{deg}.
- ID:
- ivo://CDS.VizieR/J/ApJ/681/197
- Title:
- ACS Virgo Cluster Survey. XV
- Short Name:
- J/ApJ/681/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The fraction of stellar mass contained in globular clusters (GCs), also measured by number as the specific frequency, is a fundamental quantity that reflects both a galaxy's early star formation and its entire merging history. We present specific frequencies, luminosities, and mass fractions for the globular cluster systems of 100 early-type galaxies in the ACS Virgo Cluster Survey, the largest homogeneous catalog of its kind.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A93
- Title:
- ACT-CL J0215.4+0030 NIKA2 image
- Short Name:
- J/A+A/644/A93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution mapping of the intracluster medium (ICM) up to high redshift and down to low masses is crucial to derive accurate mass estimates of the galaxy cluster and to understand the systematic effects affecting cosmological studies based on galaxy clusters. We present a spatially resolved Sunyaev-Zel'dovich (SZ) X-ray analysis of ACT-CL J0215.4+0030, a high-redshift (z=0.865) galaxy cluster of intermediate mass (M_500_~=3.5x10^14^M_{sun}_) observed as part of the ongoing NIKA2 SZ Large Program, which is a follow-up of a representative sample of objects at 0.5<=z<=0.9. In addition to the faintness and small angular size induced by its mass and redshift, the cluster is contaminated by point sources that significantly affect the SZ signal. This is therefore an interesting case study for the most challenging sources of the NIKA2 cluster sample. We present the NIKA2 observations of this cluster and the resulting data. We identified the point sources that affect the NIKA2 maps of the cluster as submillimeter galaxies (SMG) with counterparts in catalogs of sources constructed by the SPIRE instrument on board the Herschel observatory. We reconstructed the ICM pressure profile by performing a joint analysis of the SZ signal and of the point-source component in the NIKA2 150GHz map. This cluster is a very weak source that lies below the selection limit of the Planck catalog. Nonetheless, we obtained high-quality estimates of the ICM thermodynamical properties with NIKA2. We compared the pressure profile extracted from the NIKA2 map to the pressure profile obtained from X-ray data alone by deprojecting the public XMM-Newton observations of the cluster. We combined the NIKA2 pressure profile with the X-ray deprojected density to extract detailed information on the ICM. The radial distribution of its thermodynamic properties (the pressure, temperature and entropy) indicate that the cluster has a highly disturbed core. We also computed the hydrostatic mass of the cluster, which is compatible with estimations from SZ and X-ray scaling relations. We conclude that the NIKA2 SZ Large Program can deliver quality information on the thermodynamics of the ICM even for one of its faintest clusters after a careful treatment of the contamination by point sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/207
- Title:
- Action dynamics of the Local Supercluster
- Short Name:
- J/ApJ/850/207
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The fully nonlinear gravitationally induced trajectories of a nearly complete set of galaxies, groups, and clusters in the Local Supercluster are constructed in a numerical action method model constrained by data from the CosmicFlows survey and various distance indicators. We add the gravity field due to inhomogeneities external to the sample sphere by making use of larger-scale peculiar flow measurements. Assignments of total masses were made to find the best overall set of mutual attractions, as determined by a goodness criterion based on present-day radial velocities, individually for the Virgo Cluster, M31, and the Milky Way (MW), and via a mass-to-light ratio relationship for other masses. The low median chi-square found indicates that the model fits the present-day velocity flow well, but a slightly high mean chi-square may indicate that some masses underwent complex orbits. The best fit, when setting the value of H_0_ to the CosmicFlows value of 75km/s/Mpc and the WMAP value for {Omega}_m_=0.244 consistent with that H_0_, occurs with the following parameters: {Omega}_orphan_=0.077+/-0.016, M/L_K_=40+/-2L_10_^0.15^M_{sun}_/L_{sun}_ (L_10_ is the K-band luminosity in units of 10^10^L_{sun}_), a Virgo mass of 6.3+/-0.8x10^14^M_{sun}_ (M/L_K_=113+/-15M_{sun}_/L_{sun}_), and a mass for the MW plus M31 of 5.15+/-0.35x10^12^M_{sun}_. The best constant mass-to-light ratio is M/L_K_=58+/-3M_{sun}_/L_{sun}_. The Virgocentric turnaround radius is 7.3+/-0.3Mpc. We explain several interesting trends in peculiar motions for various regions now that we can construct the 3D orbital histories.
- ID:
- ivo://CDS.VizieR/J/AJ/129/26
- Title:
- A deep radio survey of Abell 2125. I
- Short Name:
- J/AJ/129/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a description of deep radio, optical, and near-IR observations taken with the VLA, the KPNO 2m telescope, and the KPNO 4m telescope of the region containing the rich cluster of galaxies Abell 2125. The reduction of each data set is described. A catalog of radio sources apparently not associated with members of A2125 and the associated R-band magnitudes is presented.
- ID:
- ivo://CDS.VizieR/J/AJ/129/31
- Title:
- A deep radio survey of Abell 2125. II
- Short Name:
- J/AJ/129/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using our extensive radio, optical, near-IR, and X-ray imaging and spectroscopy, we consider the reason for the unusually large number of radio-detected galaxies, mostly found outside the cluster core, in Abell 2125 (z=0.2465, richness class 4). With 20cm VLA data, we detect continuum emission from 90 cluster members. The multiwavelength properties of these galaxies suggest that most of the radio emission is due to an enhanced star formation rate. The recent dynamical study of Miller et al. (2004, Cat. <J/ApJ/613/841>) suggests that A2125 is undergoing a major cluster-cluster merger, with our view within 30{deg} of the merger axis and within 0.2Gyr of core passage. The combination of projection effects and the physical processes at work during this special time in the cluster's evolution seem likely to be responsible for the unusual level of activity we see in the cluster. We argue that tidal effects on individual cluster members, often far from the cluster core, are responsible for the increased star formation. Our results are consistent with the idea that disk galaxies during this phase of a cluster's evolution undergo rapid evolution through a burst of star formation on their way to becoming S0 galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/869/145
- Title:
- A 3D Voronoi+Gapper galaxy cluster finder. II.
- Short Name:
- J/ApJ/869/145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We identify 1901 galaxy clusters (N_g_>=2) with the gapping-filtering in radial velocity (VoML+G) algorithm (Paper I; Campusano+ 2017ApJ...838..109P) on the two-Degree Field Galaxy Redshift Survey (2dFGRS). We present the 341 clusters with at least 10 galaxies that are within 0.009<z<0.14 (the Catalog), of which 254 (~75%) have counterparts in the literature (NED), with the remainder (87) plausibly "new" because of incompleteness of previous searches or unusual galaxy contents. The 207 clusters within z=0.04--0.09 are used to study the properties of the galaxy systems in the nearby universe, including their galaxy contents parameterized by the late-type galaxy fractions (f_L_). For this nearly complete cluster subsample, we find the following: (i) 63% are dominated by early-type galaxies (i.e., the late-type-poor clusters, f_L_<0.5) with corresponding mean multiplicity and logarithmic virial mass (in units of M_{sun}_) of 22+/-1 and 12.91+/-0.04, respectively; and (ii) 37% are dominated by late-type galaxies (i.e., the late-type-rich clusters, f_L_>=0.5) with corresponding mean multiplicity and logarithmic virial mass (in units of M_{sun}_) of 15.7+/-0.9 and 12.66+/-0.07, respectively. The statistical analysis of the late-type fraction distribution supports, with a 3{sigma} confidence level, the presence of two population components. It is suggested that the late-type-poor galaxy systems reflect and extend the class of Abell-APM-EDCC clusters and that the late-type-rich systems (~one-third of the total) belong to a new, previously unappreciated class. The late-type-rich clusters, on average high mass-to-light ratio systems, appear to be more clustered on large scales than the late-type-poor clusters. A class of late-type-rich clusters is not predicted by current theory.
- ID:
- ivo://CDS.VizieR/J/ApJ/693/1840
- Title:
- A3266 galaxies at 24um
- Short Name:
- J/ApJ/693/1840
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Multiband Imaging Photometer observations of the cluster A3266. About 100 spectroscopic cluster members have been detected at 24um. The infrared (IR) luminosity function (LF) in A3266 is very similar to that in the Coma cluster down to the detection limit LIR~10^43^erg/s, suggesting a universal form of the bright-end IR LF for local rich clusters with M~10^15^M_{sun}_. The shape of the bright end of the A3266-Coma composite IR LF is not significantly different from that of nearby field galaxies, but the fraction of IR-bright galaxies (star formation rate (SFR)>0.2M_{sun}_/yr) in both clusters increases with cluster-centric radius. The decrease of the blue galaxy fraction toward the high-density cores only accounts for part of the trend; the fraction of red galaxies with moderate SFRs (0.2M_{sun}_/yr<SFR<1M_{sun}/yr) also decreases with increasing galaxy density. These results suggest that for the IR-bright galaxies nearby rich clusters are distinguished from the field by a lower star forming galaxy fraction, but not by a change in L*_IR_.
- ID:
- ivo://CDS.VizieR/J/MNRAS/368/651
- Title:
- A3653 galaxies redshift catalogue
- Short Name:
- J/MNRAS/368/651
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of galaxies in Abell 3653 from observations made with the 2-degree field (2dF) spectrograph at the Anglo-Australian Telescope. Of the 391 objects observed, we find 111 are bona fide members of Abell 3653.
