Morphological Fractions of Galaxies in WINGS Clusters: revisiting the Morphology-Density Paradigm
G. Fasano, B. M. Poggianti, D. Bettoni, M. Donofrio, A. Dressler, B. Vulcani, A. Moretti, M. Gullieuszik, J. Fritz, A. Omizzolo, A. Cava, W. J. Couch, M. Ramella, A. Biviano
备注:
21 pages, 17 figures, 7 tables, accepted for publication in MNRAS, online material at: ftp://ftp.oapd.inaf.it/pub/fasano/maps.pdf
We present the Morphology-Density and Morphology-Radius relations (T-Sigma and T-R, respectively) obtained from the WINGS database of galaxies in nearby clusters. Aiming to achieve the best statistics, we exploit the whole sample of galaxies brighter than MV=-19.5 (5,504 objects), stacking up the 76 clusters of the WINGS survey altogether. Using this global cluster sample, we find that the T-Sigma relation holds only in the inner cluster regions (R<1/3xR200), while the T-R relation keeps almost unchanged over the whole range of local density. A couple of tests and two sets of numerical simulations support the robustness of these results against the effects of the limited cluster area coverage of the WINGS imaging. The above mentioned results hold for all cluster masses (X-ray luminosity and velocity dispersion) and all galaxy stellar masses (M). The strength of the T-Sigma relation (where present) increases with increasing M, while this effect is not found for the T-R relation. Noticeably, the absence/presence of subclustering determines the presence/absence of the T-Sigma relation outside the inner cluster regions, leading us to the general conclusion that the link between morphology and local density is preserved just in dynamically evolved regions. We hypothesize that some mechanism of morphological broadening/redistribution operates in the intermediate/outer regions of substructured (non relaxed) clusters, producing a strong weakening of the T-Sigma relation.
A Morphological Identification and Study of Radio Galaxies from LoTSS DR2. I. The "Winged'' Radio Galaxies
Xiamen University(厦门大学);National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);Institute of Astronomy, Faculty of Physics, Astronomy and Informatics, NCU(尼古拉·哥白尼大学物理、天文与信息学学院天体物理研究所);Jadavpur University(贾达普大学)
A Morphological Identification and Study of Radio Galaxies from LoTSS DR2. III. The Multiwavelength Analysis of Winged Radio Galaxies
Xiamen University(厦门大学);Institute of Astronomy, Faculty of Physics, Astronomy and Informatics, NCU(托伦 Nicolaus Copernicus 大学物理、天文学和信息学学院天文研究所);National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU, WPI), UTIAS, Tokyo Institutes for Advanced Study, University of Tokyo(东京大学宇宙物质前沿研究センター( Kavli 宇宙物理学・数学研究中心));Jadavpur University(贾达普大学)
Galaxy morphology is a key parameter in galaxy evolution studies. The enormous number of galaxies which current and future surveys will observe demand of automated methods for morphological classification. Supervised learning techniques have been successfully used for the morphological classification of galaxies from different datasets, including Sloan Digital Sky Survey (SDSS), Mapping Galaxies with Apache Point Observatory (MaNGA) or Dark Energy Survey (DES). With these proceedings, we release the morphological catalogue for a sample of 670,000 SDSS galaxies based on the deep learning models…
The study of galaxy morphology is fundamental to understand the physical processes driving the structural evolution of galaxies. It has long been known that dense environments host high fractions of early-type galaxies and low fractions of late-type galaxies, indicating that the environment affects the structural evolution of galaxies. In this paper we present an analysis of the morphological composition of red sequence galaxies in a sample of 9 galaxy clusters at $0.8<z<1.5$ drawn from the HAWK-I cluster survey (HCS), with the aim of investigating the evolutionary paths of galaxies with diffe…
[Abridged] We use the WINGS database to select a sample of 67 nearby galaxy clusters with at least 30 spectroscopic members each. 53 of these clusters do not show evidence of substructures in phase-space, while 14 do. We estimate the virial radii and circular velocities of the 67 clusters by a variety of proxies (velocity dispersion, X-ray temperature, and richness) and use these estimates to build stack samples from these 53 and 14 clusters ('Reg' and 'Irr' stacks, respectively). We determine the number-density and velocity-dispersion profiles (VDPs) of E, S0, and Sp+Irr (S) galaxies in the R…
We present a multi-wavelength analysis of the galaxies in nine clusters selected from the WINGS dataset, examining how galaxy structure varies as a function of wavelength and environment using the state of the art software GALAPAGOSII. We simultaneously fit single Sérsic functions on three optical (u, B and V) and two near-infrared (J and K) bands thus creating a wavelength-dependent model of each galaxy. We measure the magnitudes, effective radius ($R_{e}$) the Sérsic index ($n$), axis ratio and position angle in each band. The sample contains 790 cluster members (located close to the cluster…
The relative positions of the high and low surface brightness regions of radio-loud active galaxies in the 3CR sample were found by Fanaroff and Riley to be correlated with their luminosity. We revisit this canonical relationship with a sample of 5805 extended radio-loud AGN from the LOFAR Two-Metre Sky Survey (LoTSS), compiling the most complete dataset of radio-galaxy morphological information obtained to date. We demonstrate that, for this sample, radio luminosity does *not* reliably predict whether a source is edge-brightened (FRII) or centre-brightened (FRI). We highlight a large populati…
Using V band photometry of the WINGS survey, we derive galaxy luminosity functions (LF) in nearby clusters. This sample is complete down to Mv=-15.15, and it is homogeneous, thus allowing the study of an unbiased sample of clusters with different characteristics. We constructed the photometric LF for 72 out of the original 76 WINGS clusters, excluding only those without a velocity dispersion estimate. For each cluster we obtained the LF for galaxies in a region of radius=0.5 x r200, and fitted them with single and double Schechter's functions. We also derive the composite LF for the entire sam…
We present a spatially resolved analysis of ionized gas at the nuclear region of the nearby galaxy NGC 1068. While NGC 1068 has been known to have gas outflows driven by its active galactic nucleus (AGN), more complex kinematical signatures were recently reported, which were inconsistent with a rotation or simple biconical outflows. To account for the nature of gas kinematics, we performed a spatially resolved kinematical study, finding a morphologically symmetric pair of approaching and receding gas blobs in the northeast region. The midpoint of the two blobs is located at a distance of 180 p…
Recent cosmological hydrodynamical simulations suggest that integral field spectroscopy can connect the high-order stellar kinematic moments h3 (~skewness) and h4 (~kurtosis) in galaxies to their cosmological assembly history. Here, we assess these results by measuring the stellar kinematics on a sample of 315 galaxies, without a morphological selection, using 2D integral field data from the SAMI Galaxy Survey. A proxy for the spin parameter ($λ_{R_e}$) and ellipticity ($ε_e$) are used to separate fast and slow rotators; there exists a good correspondence to regular and non-regular rotators, r…
[Abridged] To effectively investigate galaxy formation and evolution, it is of paramount importance to exploit homogeneous data for large samples of galaxies in different environments. The WINGS (WIde-field Nearby Galaxy-cluster Survey) project aim is to evaluate physical properties of galaxies in a complete sample of low redshift clusters to be used as reference sample for evolutionary studies. The WINGS survey is still ongoing and the original dataset will soon be enlarged with new observations. This paper presents the entire collection of WINGS measurements obtained so far. We decided to ma…
To investigate the effects the cluster environment has on Late-Type Galaxies (LTGs) we studied HI perturbation signatures for all Abell 1367 LTGs with HI detections. We used new VLA HI observations combined with AGES single dish blind survey data. Our study indicates that the asymmetry between the high-and low-velocity wings of the characteristic double-horn integrated HI spectrum as measured by the asymmetry parameter, Aflux, can be a useful diagnostic for ongoing and/or recent HI stripping. 26% of A1367 LTGs have an Aflux ratio, more asymmetrical than 3 times the 1σ spread in the Aflux ratio…
We present the results of a detailed analysis of galaxy properties along the red sequence in XMMU J1229+0151, an X-ray selected cluster at $z=0.98$ drawn from the HAWK-I Cluster Survey (HCS). Taking advantage of the broad photometric coverage and the availability of 77 spectra in the cluster field, we fit synthetic spectral energy distributions, and estimate stellar masses and photometric redshifts, which we use to determine the cluster membership. We investigate morphological and structural properties of red sequence galaxies and find that elliptical galaxies populate the bright end, while S0…
The stellar velocity ellipsoid (SVE) in galaxies can provide important information on the processes that participate in the dynamical heating of their disc components (e.g. giant molecular clouds, mergers, spiral density waves, bars). Earlier findings suggested a strong relation between the shape of the disc SVE and Hubble type, with later-type galaxies displaying more anisotropic ellipsoids and early-types being more isotropic. In this paper, we revisit the strength of this relation using an exhaustive compilation of observational results from the literature on this issue. We find no clear co…
Revisiting the missing mass problem in MOND for nearby galaxy clusters
Helmholtz-Institut für Strahlen-und Kernphysik (HISKP), Universität Bonn(波恩大学亥姆霍兹辐射与核物理研究所);Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS)(基础科学高等研究院物理系);Charles University in Prague, Faculty of Mathematics and Physics, Astronomical Institute(布拉格查理大学数学物理学院天文研究所)
We discuss the observational evidences of the morphological transformation of Spirals into S0 galaxies in the cluster environment exploiting two big databases of galaxy clusters: WINGS (0.04 < z < 0.07) and EDisCS (0.4 < z < 0.8). The most important results are: 1) the average number of S0 galaxies in clusters is almost a factor of $\sim 3 - 4$ larger today than at redshift $z \sim 1$; 2) the fraction of S0's to Spirals increases on average by a factor $\sim$ 2 every Gyr; 3) the average rate of transformation for Spirals (not considering the infall of new galaxies from the cosmic web) is: $\si…
The Bayesian MAMPOSSt mass/orbit modeling algorithm is used to jointly fit the distribution of elliptical, spiral (and irregular), and lenticular galaxies in projected phase space, on 3 stacked clusters (with normalized positions and velocities) of 54 regular clusters from the WINGS survey, with at least 30 member velocities. Our stacked clusters contain ~5000 galaxies with available velocities and morphological types. 30 runs of MAMPOSSt with different priors are presented. The highest MAMPOSSt likelihoods are obtained for generalized NFW models with steeper inner slope, free-index Einasto mo…
Revisiting the Milky Way stellar long bar and the 3 kpc arm
Instituto de Astrofísica de Canarias(加那利群岛天体物理研究所);Universidad de La Laguna(拉古纳大学);Inner Mongolia University(内蒙古大学);National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);China West Normal University(西华师范大学)
The observed properties of galaxies are strongly dependent on both their total stellar mass and their morphology. Furthermore, the environment is known to play a strong role in shaping them. The galaxy population in the local universe that is located in virialized clusters is found to be red, poorly star-forming, and mostly composed of early morphological types. Towards a holistic understanding of the mechanisms that drive galaxy evolution, we exploit the spectrophotometric data from the WINGS and OmegaWINGS local galaxy cluster surveys, and study the role of both the local and the large-scale…
We quantify the evolution of the spiral, S0 and elliptical fractions in galaxy clusters as a function of cluster velocity dispersion ($σ$) and X-ray luminosity ($L_X$) using a new database of 72 nearby clusters from the WIde-Field Nearby Galaxy-cluster Survey (WINGS) combined with literature data at $z=0.5-1.2$. Most WINGS clusters have $σ$ between 500 and 1100 $\rm km s^{-1}$, and $L_X$ between 0.2 and $5 \times 10^{44} \rm erg/s$. The S0 fraction in clusters is known to increase with time at the expense of the spiral population. We find that the spiral and S0 fractions have evolved more stro…
Major gas-rich mergers of galaxies are expected to play an important role in triggering and fuelling luminous AGN. We present deep multi-band (u/r/z) imaging and long slit spectroscopy of four double-peaked [OIII] emitting AGN, a class of objects associated with either kcp-separated binary AGN or final stage major mergers, though AGN with complex narrow-line regions are known contaminants. Such objects are of interest since they represent the onset of AGN activity during the merger process. Three of the objects studied have been confirmed as major mergers using near-infrared imaging, one is a …
We present the results of a Keck-ESI spectroscopic study of six dwarf elliptical (dE) galaxies in the Perseus Cluster core, and confirm two dwarfs as cluster members for the first time. All six dEs follow the size-magnitude relation for dE/dSph galaxies. Central velocity dispersions are measured for three Perseus dwarfs in our sample, and all lie on the $σ$-luminosity relation for early-type, pressure supported systems. We furthermore examine SA 0426-002, a unique dE in our sample with a bar-like morphology surrounded by low-surface brightness wings/lobes ($μ_{B} = 27$ mag arcsec$^{-2}$). Give…
We discuss the dense molecular gas in central regions of nearby Seyfert galaxies, and report new arcsec resolution observations of HCN(1-0) and HCO$^+$(1-0) for 3 objects. In NGC 3079 the lines show complex profiles as a result of self-absorption and saturated continuum absorption. H$^{13}$CN reveals the continuum absorption profile, with a peak close to the galaxy's systemic velocity that traces disk rotation, and a second feature with a blue wing extending to $-350$km s$^{-1}$ that most likely traces a nuclear outflow. The morphological and spectral properties of the emission lines allow us …
We present a detailed analysis of deep VLT/X-Shooter observations of the planetary nebula Tc 1. We calculate gas temperature, density, extinction, and abundances for several species from the empirical analysis of the total line fluxes. In addition, a spatially resolved analysis of the most intense lines provides the distribution of such quantities across the nebula. The new data reveal that several lines exhibit a double peak spectral profile consistent with the blue- and red-shifted components of an expanding spherical shell. The study of such components allowed us to construct for the first …
Galaxies that are being stripped of their gas can sometimes be recognized from their optical appearance. Extreme examples of stripped galaxies are the so-called ``jellyfish galaxies'', that exhibit tentacles of debris material with a characteristic jellyfish morphology. We have conducted the first systematic search for galaxies that are being stripped of their gas at low-z (z=0.04-0.07) in different environments, selecting galaxies with varying degrees of morphological evidence for stripping. We have visually inspected B and V-band images and identified 344 candidates in 71 galaxy clusters of …
[Abridged] We studied the size-surface brightness and the size-mass relations of a sample of 16 cluster elliptical galaxies in the mass range 10^{10}-2x10^{11} M_sun which were morphologically selected in the cluster RDCS J0848+4453 at z=1.27. Our aim is to assess whether they have completed their mass growth at their redshift or significant mass and/or size growth can or must take place until z=0 in order to understand whether elliptical galaxies of clusters follow the observed size evolution of passive galaxies. To compare our data with the local universe we considered the Kormendy relation …