- ID:
- ivo://CDS.VizieR/J/ApJ/660/1186
- Title:
- VCC galaxies classification with SDSS
- Short Name:
- J/ApJ/660/1186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- From a quantitative analysis of 413 Virgo Cluster early-type dwarf galaxies (dEs) with SDSS imaging data, we find that the dE class can be divided into multiple subpopulations that differ significantly in their morphology and clustering properties. Three dE subclasses are shaped like thick disks and show no central clustering: (1) dEs with disk features like spiral arms or bars, (2) dEs with central star formation, and (3) ordinary, bright dEs that have no or only a weak nucleus.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/552/A8
- Title:
- 454 VCC galaxies revised coordinates
- Short Name:
- J/A+A/552/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the dust content of a large optical input sample of 910 early-type galaxies (ETG) in the Virgo cluster, also extending to the dwarf ETG, and examine the results in relation to those on the other cold ISM components. We have searched for far-infrared emission in all galaxies in the input sample using the 250um image of the Herschel Virgo Cluster Survey (HeViCS). This image covers a large fraction of the cluster with an area of ~55 square degrees. For the detected ETG we measured fluxes in five bands from 100 to 500um, and estimated the dust mass and temperature with modified black-body fits. Dust is detected above the completeness limit of 25.4mJy at 250um in 46 ETG, 43 of which are in the optically complete part of the input sample. In addition, dust is present at fainter levels in another six ETG. We detect dust in the four ETG with synchrotron emission, including M 87.
- ID:
- ivo://CDS.VizieR/J/A+A/547/A44
- Title:
- Velocities and BR photometry of Abell 1995
- Short Name:
- J/A+A/547/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Abell 1995 is a puzzling galaxy cluster hosting a powerful radio halo, but it has not yet been recognized as a obvious cluster merger, as usually expected for clusters with diffuse radio emission. We aim at an exhaustive analysis of the internal structure of Abell 1995 to verify that this cluster is really dynamically relaxed, as reported in previous studies. We base our analysis on new and archival spectroscopic and photometric data for 126 galaxies in the field of Abell 1995. The study of the hot intracluster medium was performed on X-ray archival data.
- ID:
- ivo://CDS.VizieR/J/ApJ/562/254
- Title:
- Velocities in A1750, A3395 and A3528
- Short Name:
- J/ApJ/562/254
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study three prominent bimodal X-ray clusters: A3528, A1750, and A3395. Using observations taken with ROSAT and ASCA, we analyze the temperature and surface brightness distributions. We also analyze the velocity distributions of the three clusters using new measurements supplemented with previously published data. We examine both the overall cluster properties, as well as the two subcluster elements in each. These results are then applied to the determination of the overall cluster masses; they demonstrate excellent consistency between the various methods used. While the characteristic parameters of the subclusters are typical of isolated objects, our temperature results for the regions between the two subclusters clearly confirm the presence of merger activity. These three clusters represent a progression of equal-sized subcluster mergers, starting from initial contact to immediately before first core passage.
1095. Velocities in Abell 3266
- ID:
- ivo://CDS.VizieR/J/AJ/112/36
- Title:
- Velocities in Abell 3266
- Short Name:
- J/AJ/112/36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 387 velocities covering an area 1.8x1.8{deg}^2^, including 229 new galaxy velocities obtained from 309 spectra, of which 317 appear to be cluster members according to our analysis. Based on this extended velocity sample we reanalyzed the velocity structure of the cluster. We found a strongly decreasing velocity dispersion profile that, as well as the mean velocity, shows significant radial scatter. Inside the 2.5h_50_^-1^Mpc radius, the velocity dispersion has a value of 1306+/-73km/s, while further out than 3h_50_^-1^Mpc it falls below 800km/s. The global dispersion is 1085+/-51km/s. We found a remarkable velocity substructure, which we interpret as a tidal outgoing arm reaching from the center to the northernmost extensions surveyed. The arm could be produced by a recent merger with another cluster, that moved from the front and SW direction and scattered from the main cluster core into the arm. This model allows us to derive an epoch for the collision between the more massive core and the front edge of the incoming cluster of 4x10^9^h_50_^-1^yr ago and of ~2x10^9^h_50_^-1^yr for the merging of both cores. Formation of the dumb-bell is a later merger process of the two BCMs, consistent with theoretical estimates. The collision picture is also consistent with the distorted X-ray image. The very northernmost parts of the arm could, alternatively, be interpreted as ongoing infall of a few outlying loose groups. The suggestion of a faint galaxy system within 400h_50_^-1^kpc, satellite to the central dumb-bell, is maintained in spite of the large central velocity dispersion value; however, confirmation requires data for further compact faint members. From several mass estimators we derived a cluster dynamical mass value of 5x10^15^h_50_^-1^M_{sun}_, but this value should be seen in the merger context described.
- ID:
- ivo://CDS.VizieR/J/ApJ/665/1067
- Title:
- Velocities in Cl 0024+16 and MS 0451-03
- Short Name:
- J/ApJ/665/1067
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine resolved spectroscopic data obtained with the Keck II telescope for 44 spheroidal galaxies in the fields of two rich clusters, Cl 0024+16 (z=0.40) and MS 0451-03 (z=0.54) and contrast this with similar data for 23 galaxies within the redshift interval 0.3<z<0.65 in the GOODS northern field. For each galaxy we examine the case for systemic rotation, derive central stellar velocity dispersions sigma and photometric ellipticities epsilon. Using morphological classifications obtained via Hubble Space Telescope imaging as the basis, we explore the utility of our kinematic quantities in distinguishing between pressure-supported ellipticals and rotationally supported lenticulars (S0s).
- ID:
- ivo://CDS.VizieR/J/A+AS/111/265
- Title:
- Velocities in Coma cluster
- Short Name:
- J/A+AS/111/265
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/AJ/105/1251
- Title:
- Velocities in Pisces-Perseus supercluster.
- Short Name:
- J/AJ/105/1251
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Measurements of 544 radial velocities, 229 optical and 315 in the 21cm HI line, are presented for galaxies, mostly in the declination strip +33.5 deg<Dec<+39.5deg in the region of the Pisces-Perseus supercluster. These are combined with other available data to investigate the linear structure identified as the main supercluster ridge. The main ridge of the supercluster extends at least 50h^-1Mpc before it disappears into the zone of avoidance east of Perseus. Confinement both on the plane of the sky and in the velocity dimension imply an axial ratio of greater than ten to one and an inclination with respect to the plane of the sky of less than about 12 degrees. The smoothed volume density contrast over the whole ridge averages more than a factor of 6 relative to the average density derived for the whole sample. The relative proximity, low inclination to the plane of the sky, and high contrast relative to the foreground and background, help to make the Pisces-Perseus filament one of the most prominent features in the extragalactic sky on large scales.
- ID:
- ivo://CDS.VizieR/J/A+A/521/A78
- Title:
- Velocities in the A2345 cluster
- Short Name:
- J/A+A/521/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The connection of cluster mergers with the presence of extended, diffuse radio sources in galaxy clusters is still debated. We aim to obtain new insights into the internal dynamics of the cluster Abell 2345. This cluster exhibits two non-symmetric radio relics well studied through recent, deep radio data. Our analysis is based on redshift data for 125 galaxies acquired at the Telescopio Nazionale Galileo and on new photometric data acquired at the Isaac Newton Telescope. We also use ROSAT/HRI archival X-ray data. We combine galaxy velocities and positions to select 98 cluster galaxies and analyze the internal dynamics of the cluster.
- ID:
- ivo://CDS.VizieR/J/MNRAS/369/1351
- Title:
- Velocities in the possible Eridanus group
- Short Name:
- J/MNRAS/369/1351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine a possible supergroup in the direction of the Eridanus constellation using 6dF Galaxy Survey second data release (6dFGS DR2) positions and velocities together with Two-Micron All-Sky Survey and Hyper-Lyon-Meudon Extragalactic DAtabase photometry. We perform a friends-of-friends analysis to determine which galaxies are associated with each substructure before examining the properties of the constituent galaxies.
