- ID:
- ivo://CDS.VizieR/J/ApJS/107/1
- Title:
- Morphologies of distant galaxies II
- Short Name:
- J/ApJS/107/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The morphological properties of high-redshift galaxies are investigated using a sample of 507 objects (I<22.0mag) from the Hubble Space Telescope (HST) Medium Deep Survey. Independent visual morphological classifications for each galaxy are used to quantify the statistical uncertainties in the galaxy classifications. Visual classifications are found to agree well for I<21mag. Fainter than I=21mag significant disagreements are seen in the independent visual classifications of late-type systems with T>7, merging systems, and peculiar galaxies. The classifications of these systems are shown to be somewhat subjective. Objective classifications based upon measurements of central concentration and asymmetry for the Medium Deep Survey sample are presented. These classifications are calibrated using measurements of structural parameters for an artificially redshifted sample of local objects. Morphologically segregated number counts using both sets of visual classifications and objective classifications support the conclusion that the observed galaxy counts agree with no-evolution predictions for the elliptical and spiral populations, as reported in Glazebrook et al. (1995MNRAS.275L..19G). A major conclusion is that the large overdensity of merging/ peculiar/ irregular galaxies relative to the predictions of no-evolution models (reported by Glazebrook et al. 1995MNRAS.275L..19G) is confirmed. However, the shape of the faint-end (I>21.0mag) number count relation for peculiar objects is sensitive to the large systematic uncertainties inherent in the visual classification of these objects. Despite this caveat, the frequency of objects showing clear evidence for tidal interactions (e.g., tidal tails) in the HST sample is at least 50% larger than it is among nearby galaxies, at the 2{sigma} level. Relatively few "chain galaxies" are seen among the sample of peculiar objects, suggesting that these systems do not form a large component of the peculiar galaxy population at I<22mag.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/444/3015
- Title:
- Morphologies of S4G galaxies
- Short Name:
- J/MNRAS/444/3015
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue and images of visually detected features, such as asymmetries, extensions, warps, shells, tidal tails, polar rings, and obvious signs of mergers or interactions, in the faint outer regions (at and outside of R_25_) of nearby galaxies. This catalogue can be used in future quantitative studies that examine galaxy evolution due to internal and external factors. We are able to reliably detect outer region features down to a brightness level of 0.03MJy/sr/pixel at 3.6{mu}m in the Spitzer Survey of Stellar Structure in Galaxies (S4G). We also tabulate companion galaxies. We find asymmetries in the outer isophotes in 22+/-1% of the sample. The asymmetry fraction does not correlate with galaxy classification as an interacting galaxy or merger remnant, or with the presence of companions. We also compare the detected features to similar features in galaxies taken from cosmological zoom re-simulations. The simulated images have a higher fraction (33%) of outer disc asymmetries, which may be due to selection effects and an uncertain star formation threshold in the models. The asymmetries may have either an internal (e.g. lopsidedness due to dark halo asymmetry) or external origin.
- ID:
- ivo://CDS.VizieR/J/ApJS/219/15
- Title:
- Morphologies of z=0-10 galaxies with HST data
- Short Name:
- J/ApJS/219/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the redshift evolution of the galaxy effective radius r_e_ obtained from the Hubble Space Telescope (HST) samples of ~190000 galaxies at z=0-10. Our HST samples consist of 176152 photo-z galaxies at z=0-6 from the 3D-HST+CANDELS catalog (Skelton+, 2014, J/ApJS/214/24) and 10454 Lyman break galaxies (LBGs) at z=4-10 identified in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), HUDF 09/12, and HFF parallel fields, (Harikane+, 2015, in prep) providing the largest data set to date for galaxy size evolution studies. We derive r_e_ with the same technique over the wide redshift range of z=0-10, evaluating the optical-to-UV morphological K correction and the selection bias of photo-z galaxies+LBGs as well as the cosmological surface-brightness dimming effect.
- ID:
- ivo://CDS.VizieR/J/ApJS/217/27
- Title:
- Morphologies of z<0.01 SDSS-DR7 galaxies
- Short Name:
- J/ApJS/217/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The morphological types of 5836 galaxies were classified by a visual inspection of color images using the Sloan Digital Sky Survey Data Release 7 to produce a morphology catalog of a representative sample of local galaxies with z<0.01. The sample galaxies are almost complete for galaxies brighter than r_pet_=17.77. Our classification system is basically the same as that of the Third Reference Catalog of Bright Galaxies with some simplifications for giant galaxies. On the other hand, we distinguish the fine features of dwarf elliptical (dE)-like galaxies to classify five subtypes: dE, blue-cored dwarf ellipticals, dwarf spheroidals (dSph), blue dwarf ellipticals (dE_blue_), and dwarf lenticulars (dS0). In addition, we note the presence of nucleation in dE, dSph, and dS0. Elliptical galaxies and lenticular galaxies contribute only ~1.5 and 4.9% of local galaxies, respectively, whereas spirals and irregulars contribute ~32.1 and ~42.8%, respectively. The dE_blue_ galaxies, which are a recently discovered population of galaxies, contribute a significant fraction of dwarf galaxies. There seem to be structural differences between dSph and dE galaxies. The dSph galaxies are fainter and bluer with a shallower surface brightness gradient than dE galaxies. They also have a lower fraction of galaxies with small axis ratios (b/a<~0.4) than dE galaxies. The mean projected distance to the nearest neighbor galaxy is ~260 kpc. About 1% of local galaxies have no neighbors with comparable luminosity within a projected distance of 2Mpc.
- ID:
- ivo://CDS.VizieR/J/AJ/146/151
- Title:
- Morphology catalog of nearby galaxies from SDSS DR7
- Short Name:
- J/AJ/146/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the statistical properties of a volume-limited sample of 7429 nearby (z=0.033-0.044) galaxies from the Sloan Digital Sky Survey Data Release 7. Our database includes morphology distribution as well as the structural and spectroscopic properties of each morphology type based on the recent remeasurements of spectral line strengths by Oh and collaborators. Our database does not include galaxies that are apparently smaller and flatter because morphology classification of them turned out to be difficult. Our statistics confirmed the up-to-date knowledge of galaxy populations, e.g., correlations between morphology and line strengths as well as the derived ages. We hope that this database will be useful as a reference.
- ID:
- ivo://CDS.VizieR/J/ApJ/652/1068
- Title:
- Morphology of cool and warm infrared galaxies
- Short Name:
- J/ApJ/652/1068
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have analyzed a sample of nearby cool and warm infrared (IR) galaxies using photometric and structural parameters. The set of measures include far-infrared color [C=log(S_60um_/S_100um_)], total IR luminosity (L_FIR_), radio surface brightness, and radio, near-infrared, and optical sizes.
2377. Morphology of galaxies
- 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.
- ID:
- ivo://CDS.VizieR/J/A+A/490/923
- Title:
- Morphology of galaxies in Coma cluster direction
- Short Name:
- J/A+A/490/923
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents morphological type, membership and U-V colour for a sample of galaxies in the Coma cluster direction, complete down to M_B_=-15.00mag and extending down to M_B_=-14.25mag. We have examined 1155 objects from the GMP 1983 catalogue on B and V images of the CFH12K camera, and obtained the Hubble type in most cases. Coma cluster membership for 473 galaxies has been derived using morphology, apparent size and surface brightness, and, afterward, redshift. The comparison between morphology- and redshift- memberships and of luminosity functions derived from this morphologically-selected sample, or using statistical members or spectroscopic members, both show that the morphological membership provided here can be trusted. For the first time the morphological classification of Coma galaxies reaches faint enough magnitudes to observe the whole magnitude range of the giant types, E, S0 and spiral stages. The data presented in this paper makes our sample the richest environment where membership and morphology for complete samples down to faint magnitudes (M_B_~-15mag) are available, hence enlarging the baseline of environmental studies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/420/926
- Title:
- Morphology of galaxies in WINGS clusters
- Short Name:
- J/MNRAS/420/926
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the morphological catalog of galaxies in nearby clusters of the WINGS survey (Fasano et al., 2006A&A...445..805F). The catalog contains a total number of 39923 galaxies, for which we provide the automatic estimates of the morphological type applying the purposely devised tool MORPHOT to the V-band WINGS imaging. For ~3000 galaxies we also provide visual estimates of the morphological types. A substantial part of the paper is devoted to the description of the MORPHOT tool, whose application is limited, at least for the moment, to the WINGS imaging only. The approach of the tool to the automation of morphological classification is a non parametric and fully empirical one. In particular, MORPHOT exploits 21 morphological diagnostics, directly and easily computable from the galaxy image, to provide two independent classifications: one based on a Maximum Likelihood (ML), semi-analytical technique, the other one on a Neural Network (NN) machine. A suitably selected sample of ~1000 visually classified WINGS galaxies is used to calibrate the diagnostics for the ML estimator and as a training set in the NN machine. The final morphological estimator combines the two techniques and proves to be effective both when applied to an additional test sample of ~1000 visually classified WINGS galaxies and when compared with small samples of SDSS galaxies visually classified by Fukugita et al. (2007, Cat. J/AJ/134/579) and Nair et al. (2010, Cat. J/ApJS/186/427). Finally, besides the galaxy morphology distribution (corrected for field contamination) in the WINGS clusters, we present the ellipticity, color (B-V) and Sersic index (n) distributions for different morphological types, as well as the morphological fractions as a function of the clustercentric distance (in units of R200).
