- ID:
- ivo://CDS.VizieR/J/MNRAS/434/1443
- Title:
- SN Ia inside rich galaxy clusters
- Short Name:
- J/MNRAS/434/1443
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used the Gaussian Mixture Brightest Cluster Galaxy catalogue and Sloan Digital Sky Survey-II supernovae data with redshifts measured by the Baryon Oscillation Spectroscopic Survey to identify 48 Type Ia supernovae (SNe Ia) residing in rich galaxy clusters and compare their properties with 1015 SNe Ia in the field. Their light curves were parametrized by the SALT2 model and the significance of the observed differences was assessed by a resampling technique. To test our samples and methods, we first looked for known differences between SNe Ia residing in active and passive galaxies. We confirm that passive galaxies host SNe Ia with smaller stretch, weaker colour-luminosity relation [{beta} of 2.54(22) against 3.35(14)], and that are ~ 0.1mag more luminous after stretch and colour corrections. We show that only 0.02 percent of random samples drawn from our set of SNe Ia in active galaxies can reach these values. Reported differences in the Hubble residuals scatter could not be detected, possibly due to the exclusion of outliers. We then show that, while most field and cluster SNe Ia properties are compatible at the current level, their stretch distributions are different (~3{sigma}): besides having a higher concentration of passive galaxies than the field, the cluster's passive galaxies host SNe Ia with an average stretch even smaller than those in field passive galaxies (at 95 percent confidence). We argue that the older age of passive galaxies in clusters is responsible for this effect since, as we show, old passive galaxies host SNe Ia with smaller stretch than young passive galaxies (~4{sigma}).
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/191/340
- Title:
- Southern Cosmology Survey. II.
- Short Name:
- J/ApJS/191/340
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 105 rich and massive (M>3x10^14^M_{sun}_) optically selected clusters of galaxies extracted from 70deg^2^ of public archival griz imaging from the Blanco 4m telescope acquired over 45 nights between 2005 and 2007. We use the clusters' optically derived properties to estimate photometric redshifts, optical luminosities, richness, and masses. We complement the optical measurements with archival XMM-Newton and ROSAT X-ray data which provide additional luminosity and mass constraints on a modest fraction of the cluster sample. Two of our clusters show clear evidence for central lensing arcs; one of these has a spectacular large diameter, nearly complete Einstein Ring surrounding the brightest cluster galaxy.
- ID:
- ivo://CDS.VizieR/J/MNRAS/400/1962
- Title:
- Southern GEMS groups. II.
- Short Name:
- J/MNRAS/400/1962
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the neutral hydrogen (HI) content of 16 groups for which we have multiwavelength data including X-ray observations. Wide-field imaging of the groups was obtained with the 20cm multibeam system on the 64m Parkes telescope. We have detected 10 previously uncatalogued HI sources, one of which has no visible optical counterpart. We examine the HI properties of the groups, compared to their X-ray characteristics, finding that those groups with a higher X-ray temperature and luminosity contain less HI per galaxy.
- ID:
- ivo://CDS.VizieR/VII/28
- Title:
- Southern Groups and Clusters of Galaxies
- Short Name:
- VII/28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is the result of a survey of film copies of the ESO B plates for southern clusters of galaxies. Because of the varying quality of the ESO films and the scattered placement of the fields searched, the present survey is not intended for use in statistical studies. Nevertheless, the clusters and groups are listed from a representative sample of nearby to distant systems that is spread across the southern sky. The catalog contains cluster identification number based on a right ascension, declination numbering scheme; the ESO field number (see ADC catalog 6030); position of cluster center on plate (in mm); concentration class type of cluster; estimate of the number of galaxies; asterisk for uncertainty assignment previous value; distance class; and previous designations.
- ID:
- ivo://CDS.VizieR/J/ApJS/81/413
- Title:
- Southern sky survey of 1355 spiral galaxies
- Short Name:
- J/ApJS/81/413
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data from photometric and spectroscopic observations of 1355 southern spiral galaxies are presented and used to determine their distances and peculiar velocities via the Tully-Fisher (TF) relation. I-band CCD surface photometry was carried out using the 1-m and 3.9-m telescopes at Siding Spring Observatory. H-alpha rotation curves for 965 galaxies and 551 H I profiles are presented. The physical parameters, photometric and velocity data, distances, and peculiar velocities of the galaxies are presented in tabular form. The mean distance, systemic velocity, and average peculiar velocity of 24 clusters in the sample are given. TF diagrams are presented for each cluster.
- ID:
- ivo://CDS.VizieR/J/ApJ/682/821
- Title:
- Spectral fits of galaxy clusters in X-ray
- Short Name:
- J/ApJ/682/821
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the band dependence of the inferred X-ray temperature of the intracluster medium (ICM) for 192 well-observed galaxy clusters selected from the Chandra Data Archive. If the hot ICM is nearly isothermal in the projected region of interest, the X-ray temperature inferred from a broadband (0.7-7.0keV) spectrum should be identical to the X-ray temperature inferred from a hard-band (2.0-7.0keV) spectrum. However, if unresolved cool lumps of gas are contributing soft X-ray emission, the temperature of a best-fit single-component thermal model will be cooler for the broadband spectrum than for the hard-band spectrum. Using this difference as a diagnostic, the ratio of best-fitting hard-band and broadband temperatures may indicate the presence of cooler gas even when the X-ray spectrum itself may not have sufficient signal-to-noise ratio (S/N) to resolve multiple temperature components. To test this possible diagnostic, we extract X-ray spectra from core-excised annular regions for each cluster in our archival sample. We compare the X-ray temperatures inferred from single-temperature fits when the energy range of the fit is 0.7-7.0keV (broad) and when the energy range is 2.0/(1+z)-7.0keV (hard). We find that the hard-band temperature is significantly higher, on average, than the broadband temperature. On further exploration, we find this temperature ratio is enhanced preferentially for clusters which are known merging systems. In addition, cool-core clusters tend to have best-fit hard-band temperatures that are in closer agreement with their best-fit broadband temperatures. We show, using simulated spectra, that this diagnostic is sensitive to secondary cool components (T_X_=0.5-3.0keV) with emission measures >=10-30% of the primary hot component.
- ID:
- ivo://CDS.VizieR/J/A+A/570/A40
- Title:
- Spectra of Abell 2384 galaxies
- Short Name:
- J/A+A/570/A40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectrophotometric analysis of the galaxy population in the area of the merging cluster Abell 2384 at z=0.094. We investigate the impact of the complex cluster environment on galaxy properties, such as colour, morphology, and star formation rate. We combined multi-object spectroscopy from the 2dF and EFOSC2 spectrographs with optical imaging of the inner 30x30-arcmin of A2384 taken with the ESO Wide Field Imager. We carried out a kinematical analysis using the EMMIX algorithm and biweight statistics. We address the possible presence of cluster substructures with the Dressler-Shectman test. Cluster galaxies are investigated with respect to [OII] and H{alpha} equivalent width. Galaxies covered by our optical imaging observations are additionally analysed in terms of colour, star formation rate, and morphological descriptors, such as Gini coefficient and M20 index. We study cluster galaxy properties as a function of clustercentric distance and investigate the distribution of various galaxy types in colour-magnitude and physical space.
- ID:
- ivo://CDS.VizieR/J/A+A/417/499
- Title:
- Spectrophotometry of Virgo cluster galaxies
- Short Name:
- J/A+A/417/499
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Drift-scan mode (3600-6800{AA}) spectra with 500<R<1000 resolution are presented for 333 galaxies members to nearby clusters, covering the whole Hubble sequence. The majority (225) were obtained for galaxies in the Virgo cluster where a completeness of 36%, if all Hubble types are considered, and of 5 %, restricting to late-types, was reached at mp<=16. Our data can be therefore considered representative of the integrated spectral properties of giant and dwarf galaxies in this cluster. Intensities and equivalent widths (EWs) are derived for the principal lines, both in emission and in absorption. Deblending of the underlying absorption from emission was achieved in most cases.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/181
- Title:
- Spectroscopic analysis of EDisCS clusters
- Short Name:
- J/ApJ/850/181
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A major question in galaxy formation is how the gas supply that fuels activity in galaxies is modulated by their environment. We use spectroscopy of a set of well-characterized clusters and groups at 0.4<z<0.8 from the ESO Distant Cluster Survey and compare it to identically selected field galaxies. Our spectroscopy allows us to isolate galaxies that are dominated by old stellar populations. Here we study a stellar-mass-limited sample (log(M*/M_{sun}_)>10.4) of these old galaxies with weak [OII] emission. We use line ratios and compare to studies of local early-type galaxies to conclude that this gas is likely excited by post-AGB stars and hence represents a diffuse gas component in the galaxies. For cluster and group galaxies the fraction with EW([OII])>5{AA} is f[OII]=0.08_-0.02_^+0.03^ and f[OII]=0.06_-0.04_^+0.07^, respectively. For field galaxies we find f[OII]=0.27_-0.06_^+0.07^, representing a 2.8{sigma} difference between the [OII] fractions for old galaxies between the different environments. We conclude that a population of old galaxies in all environments has ionized gas that likely stems from stellar mass loss. In the field galaxies also experience gas accretion from the cosmic web, and in groups and clusters these galaxies have had their gas accretion shut off by their environment. Additionally, galaxies with emission preferentially avoid the virialized region of the cluster in position-velocity space. We discuss the implications of our results, among which is that gas accretion shutoff is likely effective at group halo masses (logM/M_{sun}_>12.8) and that there are likely multiple gas removal processes happening in dense environments.
- ID:
- ivo://CDS.VizieR/J/ApJS/188/280
- Title:
- Spectroscopic catalog in 24 clusters
- Short Name:
- J/ApJS/188/280
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectroscopic catalog of (mostly) red galaxies in 24 galaxy clusters in the redshift range 0.17<z<0.92 obtained with the LRIS instrument on the Keck I telescope. Here we describe the observations and the galaxy spectra, including the discovery of three cD galaxies with LINER emission spectra, and the spectroscopic discovery of four new galaxy-galaxy lenses in cluster environments. All but two of the galaxy clusters observed as part of this experiment were previously known.
