- ID:
- ivo://CDS.VizieR/J/ApJ/903/151
- Title:
- MMT spectroscopic redshift catalog of the A521 field
- Short Name:
- J/ApJ/903/151
- Date:
- 21 Mar 2022 05:59:04
- Publisher:
- CDS
- Description:
- A521 has been a subject of extensive panchromatic studies from X-ray to radio. The cluster possesses a number of remarkable features, including a bright radio relic with a steep spectrum, more than three distinct galaxy groups forming a filament, and two disturbed X-ray peaks at odds with the distant position and tilted orientation of the radio relic. These lines of evidence indicate a complex merger. In this paper, we present a multiwavelength study of A521 based on Subaru optical, Hubble Space Telescope infrared, Chandra X-ray, Giant Metrewave Radio Telescope radio, and Multiple Mirror Telescope optical spectroscopic observations. Our weak-lensing (WL) analysis with improved systematics control reveals that A521 is mainly composed of three substructures aligned in the northwest to southeast orientation. These WL mass substructures are remarkably well-aligned with the cluster optical luminosity distribution constructed from our new enhanced cluster member catalog. These individual substructure masses are determined by simultaneously fitting three Navarro-Frenk-White profiles. We find that the total mass of A521 modeled by the superposition of the three halos is 13.0_-1.3_^+1.0^x10^14^M{odot}, a factor of 2 higher than the previous WL measurement. With these WL mass constraints combined with X-ray and radio features, we consider two merging scenarios, carry out the corresponding numerical simulations, and discuss the strengths and weaknesses of each case.
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- ID:
- ivo://CDS.VizieR/J/A+A/540/A96
- Title:
- Molecular gas in Hickson Compact Groups
- Short Name:
- J/A+A/540/A96
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the effect of the extreme environment in Hickson Compact Groups (HCGs) on the molecular gas mass, M_H2_, and the star formation rate (SFR) of galaxies as a function of atomic hydrogen (HI) content and evolutionary phase of the group. We selected a redshift-limited (D<100Mpc) sample of 88 galaxies in 20 HCGs with available atomic hydrogen (HI) VLA maps, covering a wide range of HI deficiencies and evolutionary phases of the groups containing at least one spiral galaxy. We observed the CO(1-0) and CO(2-1) lines with the IRAM 30m telescope for 47 galaxies. Together with literature data, our sample contains CO(1-0) spectra for 86 galaxies. We derived the far-infrared (FIR) luminosity L_FIR_ from IRAS data and used it as a tracer of the star formation rate (SFR). We calculated the HI mass, M_HI_ L_FIR_ and M_H2_ deficiencies, based on the values expected from L_B_ and L_K_ in isolated galaxies from the AMIGA sample. We limited our statistical analysis to spiral galaxies, since the large number of upper limits did not allow drawing strong conclusions about M_H2_ and L_FIR_ in early-type galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/432/3141
- Title:
- Morphological classification of PM2GC galaxies
- Short Name:
- J/MNRAS/432/3141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the galaxy stellar mass function in different environments in the local Universe, considering both the total mass function and that of individual galaxy morphological types. We compare the mass functions of galaxies with log_10_M*/M_{sun}_>=10.25 in the general field and in galaxy groups, binary and single galaxy systems from the Padova-Millennium Galaxy and Group Catalogue at z=0.04-0.1 with the mass function of galaxy clusters of the WIde-field Nearby Galaxy-Cluster Survey at z=0.04-0.07. Strikingly, the variations of the mass function with global environment, overall, are small and subtle. The shapes of the mass functions of the general field and clusters are indistinguishable, and only small, statistically insignificant variations are allowed in groups. Only the mass function of our single galaxies, representing the least massive haloes and comprising less than a third of the general field population, is proportionally richer in low-mass galaxies than other environments. The most notable environmental effect is a progressive change in the upper galaxy mass, with very massive galaxies found only in the most massive environments. This environment-dependent mass cut-off is unable to affect the Schechter parameters and the Kolmogorov-Smirnov test, and can only be revealed by an ad hoc analysis. Finally, we show how, in each given environment, the mass function changes with morphological type, and that galaxies of the same morphological type can have different mass functions in different environments.
- ID:
- ivo://CDS.VizieR/VII/174
- Title:
- Morphological type catalog in 55 rich galaxy clusters
- Short Name:
- VII/174
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Data are presented from a study of 55 rich clusters of galaxies. The data include positions, morphological types, estimated total magnitudes, bulge sizes, and ellipticities for ~6000 galaxies, as determined from high scale photographic plates. data reduction procedures are described, and a brief analysis of cluster richness, which indicates that Abell richness classes are only rough indicators of total cluster membership, is included.
- ID:
- ivo://CDS.VizieR/J/ApJS/110/213
- Title:
- Morphological Types in 10 Distant Rich Clusters
- Short Name:
- J/ApJS/110/213
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present catalogs of objects detected in deep images of 11 fields in 10 distant clusters obtained using WFPC-2 on board the Hubble Space Telescope. The clusters span the redshift range z=0.37-0.56 and are the subject of a detailed ground- and space-based study to investigate the evolution of galaxies as a function of environment and epoch. The data presented here include positions, photometry and basic morphological information on ~9000 objects in the fields of the 10 clusters. For a brighter subset of 1857 objects in these areas, we provide more detailed morphological information.
- ID:
- ivo://CDS.VizieR/J/ApJ/542/673
- Title:
- Morphological types of galaxies in clusters
- Short Name:
- J/ApJ/542/673
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The morphological types of galaxies in nine clusters in the redshift range 0.1<~z<~0.25 are derived from very good seeing images taken at the North Optical Telescope (NOT) and the La Silla-Danish telescopes, with all galaxies at M_V_<-20 and within the central ~1Mpc^2^ area being classified. With the purpose of investigating the evolution of the fraction of different morphological types with redshift, we compare our results with the morphological content of nine distant clusters studied by the MORPHS group, five clusters observed with HST/WFPC2 at redshift z=0.2-0.3, and Dressler's large sample of nearby clusters.
- ID:
- ivo://CDS.VizieR/J/MNRAS/376/125
- Title:
- Morphologies and photometry in A2218
- Short Name:
- J/MNRAS/376/125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the stellar populations and morphologies of galaxies in the core of the galaxy cluster Abell 2218. Integral field spectroscopy (IFS) observations were performed using PMAS in the PPAK mode covering a field of view of ~74x64arcsec^2^ centred on the core of the cluster, in order to obtain spectroscopy of an unbiased flux-limited sample of cluster galaxies. 43 objects were detected in the IFS data, 31 of them with enough signal-to-noise ratio to derive the redshift, all of them brighter than I<21.5mag. 28 are at the redshift of the cluster (17 with previously unknown redshift). Individual spectra of the cluster members were extracted and compared with single stellar population models to derive the luminosity-weighted ages and metallicities. In addition, deep Hubble Space Telescope (HST)/ACS F475W-, F555W-, F625W- and F850LP-band images centred on the cluster core were obtained from the HST archive (zlim~28mag). A detailed morphological analysis of all the galaxies within the field of view of these images down to zlim<22.5mag was performed classifying them as late-type, intermediate and early-type, on the basis of their Sersic indices. The literature was scanned to look for spectroscopically confirmed cluster members located within the field of view of the ACS image. The final sample of 59 galaxies comprises our reported sample of 28 galaxies in the core, and 31 additional galaxies in the outer regions. In addition, multiband broad-band photometry was extracted from the literature for all objects.
- ID:
- ivo://CDS.VizieR/J/MNRAS/448/2530
- Title:
- Morphology and structure of BCG
- Short Name:
- J/MNRAS/448/2530
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study a large sample of 625 low-redshift brightest cluster galaxies (BCGs) and link their morphologies to their structural properties. We derive visual morphologies and find that ~57% of the BCGs are cD galaxies, ~13% are ellipticals, and ~21% belong to the intermediate classes mostly between E and cD. There is a continuous distribution in the properties of the BCG's envelopes, ranging from undetected (E class) to clearly detected (cD class), with intermediate classes (E/cD and cD/E) showing the increasing degrees of the envelope presence. A minority (~7%) of BCGs have disc morphologies, with spirals and S0s in similar proportions, and the rest (~2%) are mergers. After carefully fitting the galaxies light distributions by using one-component (Sersic) and two-component (Sersic+Exponential) models, we find a clear link between the BCGs morphologies and their structures and conclude that a combination of the best-fitting parameters derived from the fits can be used to separate cD galaxies from non-cD BCGs. In particular, cDs and non-cDs show very different distributions in the R_e_-RFF plane, where R_e_ is the effective radius and RFF (the residual flux fraction) measures the proportion of the galaxy flux present in the residual images after subtracting the models. In general, cDs have larger R_e_ and RFF values than ellipticals. Therefore we find, in a statistically robust way, a boundary separating cD and non-cD BCGs in this parameter space. BCGs with cD morphology can be selected with reasonably high completeness (~75%) and low contamination (~20%). This automatic and objective technique can be applied to any current or future BCG sample with good-quality images.
- ID:
- ivo://CDS.VizieR/J/AJ/131/143
- Title:
- Morphology of galaxies
- Short Name:
- J/AJ/131/143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comparison of late-type galaxies (Sa and later) in intermediate-redshift clusters and in the field using images from the Advanced Camera for Surveys aboard the Hubble Space Telescope. Cluster and field galaxies are selected by matching photometric and spectroscopic catalogs of four cluster fields: Cl 0152-1357, Cl 1056-0337 (MS 1054), Cl 1604+4304, and Cl 1604+4321. Concentration, asymmetry, and clumpiness parameters are calculated for each galaxy in blue (F606W or F625W) and red (F775W or F814W) filters. Galaxy half-light radii, disk scale lengths, color gradients, and overall color are compared.
- ID:
- ivo://CDS.VizieR/J/ApJ/602/664
- Title:
- Morphology of galaxies in Coma cluster core
- Short Name:
- J/ApJ/602/664
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a quantitative morphological analysis of 187 galaxies in a region covering the central 0.28deg^2^ of the Coma Cluster. Structural parameters from the best-fitting Sersic r^1/n^ bulge plus, where appropriate, exponential disk model, are tabulated here. This sample is complete down to a magnitude of R=17mag. By examining the recent compilation by Edwards et al. (2002ApJ...567..178E) of galaxy redshifts in the direction of Coma, we find that 163 of the 187 galaxies are Coma Cluster members and that the rest are foreground and background objects. For the Coma Cluster members, we have studied differences in the structural and kinematic properties between early- and late-type galaxies and between the dwarf and giant galaxies.
