- ID:
- ivo://CDS.VizieR/J/MNRAS/306/857
- Title:
- ROSAT Brightest Cluster Sample. III.
- Short Name:
- J/MNRAS/306/857
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new spectra of dominant galaxies in X-ray-selected clusters of galaxies, which combine with our previously published spectra to form a sample of 256 dominant galaxies in 215 clusters. 177 of the clusters are members of the ROSAT Brightest Cluster Sample (BCS; Ebeling et al., 1998MNRAS.301..881E), and 17 have no previous measured redshift. This is the first paper in a series correlating the properties of brightest cluster galaxies and their host clusters in the radio, optical and X-ray wavebands.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/442/3329
- Title:
- Rotation measures of 2642 quasars
- Short Name:
- J/MNRAS/442/3329
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained the rotation measures (RMs) of 2642 quasars by using cross-identification of the most updated quasar catalogue and the RM catalogue. After discounting the foreground Galactic Faraday rotation of the Milky Way, we obtain the residual rotation measure (RRM) of these quasars. We have carefully discarded the effects from measurement and systematical uncertainties of RRMs as well as large RRMs from RM outliers, and we have obtained marginal evidence for the redshift evolution of the real dispersion of RRMs which steadily increases to 10rad/m^2^ about z~1 and is saturated at higher redshifts. Ionized clouds in the form of galaxy halos, galaxy clusters or cosmological filaments with different RM dispersion widths could produce the observed RRM evolutions. However, current data sets cannot constrain the contributions from galaxy halos and cosmic webs. Future measurements of RMs for a large sample of quasars with high precision are necessary to disentangle these different contributions.
- ID:
- ivo://CDS.VizieR/J/MNRAS/449/4010
- Title:
- SALT galaxy clusters detected by ACT
- Short Name:
- J/MNRAS/449/4010
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Southern African Large Telescope follow-up observations of seven massive clusters detected by the Atacama Cosmology Telescope (ACT) on the celestial equator using the Sunyaev-Zel'dovich (SZ) effect. We conducted multi-object spectroscopic observations with the Robert Stobie Spectrograph in order to measure galaxy redshifts in each cluster field, determine the cluster line-of-sight velocity dispersions, and infer the cluster dynamical masses. We find that the clusters, which span the redshift range 0.3<z<0.55, range in mass from (5-20)x10^14^M_{sun}_ (M_200c_). Their masses, given their SZ signals, are similar to those of Southern hemisphere ACT clusters previously observed using Gemini and the VLT. We note that the brightest cluster galaxy in one of the systems studied, ACT-CL J0320.4+0032 at z=0.38, hosts a type II quasar. Only a handful of such systems are currently known, and therefore ACT-CL J0320.4+0032 may be a rare example of a very massive halo in which quasar-mode feedback is actively taking place.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/1567
- Title:
- SAMI Galaxy Survey: EDR
- Short Name:
- J/MNRAS/446/1567
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Early Data Release of the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. The SAMI Galaxy Survey is an ongoing integral field spectroscopic survey of ~3400 low-redshift (z<0.12) galaxies, covering galaxies in the field and in groups within the Galaxy And Mass Assembly (GAMA) survey regions, and a sample of galaxies in clusters. In the Early Data Release, we publicly release the fully calibrated data cubes for a representative selection of 107 galaxies drawn from the GAMA regions, along with information about these galaxies from the GAMA catalogues. All data cubes for the Early Data Release galaxies can be downloaded individually or as a set from the SAMI Galaxy Survey website. In this paper we also assess the quality of the pipeline used to reduce the SAMI data, giving metrics that quantify its performance at all stages in processing the raw data into calibrated data cubes. The pipeline gives excellent results throughout, with typical sky subtraction residuals in the continuum of 0.9-1.2 per cent, a relative flux calibration uncertainty of 4.1 per cent (systematic) plus 4.3 per cent (statistical), and atmospheric dispersion removed with an accuracy of 0.09-arcsec, less than a fifth of a spaxel.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/2690
- Title:
- Sample of Compact Group (CG) galaxies
- Short Name:
- J/MNRAS/423/2690
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We construct a sample of 75863 star-forming galaxies with robust metallicity and star formation rate (SFR) measurements from the Sloan Digital Sky Survey Data Release 7, from which we select a clean sample of compact group (CG) galaxies. The CGs are defined to be close configurations of at least four galaxies that are otherwise apparently isolated. Our selection results in a sample of 112 spectroscopically identified CG galaxies, which can be further divided into groups that are either embedded within a larger structure, such as a cluster or large group, or truly isolated systems. The CGs then serve as a probe into the influence of large-scale environment on a galaxy's evolution, while keeping the local density fixed at high values. W
- ID:
- ivo://CDS.VizieR/J/MNRAS/452/2553
- Title:
- Sample of foreground-background quasar pairs
- Short Name:
- J/MNRAS/452/2553
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Previous observations of quasar host haloes at z~2 have uncovered large quantities of cool gas that exceed what is found around inactive galaxies of both lower and higher masses. To better understand the source of this excess cool gas, we compiled an exhaustive sample of 195 quasars at z~1 with constraints on chemically enriched, cool gas traced by MgII absorption in background quasar spectra from the Sloan Digital Sky Survey. This quasar sample spans a broad range of luminosities from L_bol_=10^44.4^ to 10^46.8^erg/s and allows an investigation of whether halo gas properties are connected with quasar properties. We find a strong correlation between luminosity and cool gas covering fraction. In particular, low-luminosity quasars exhibit a mean gas covering fraction comparable to inactive galaxies of similar masses, but more luminous quasars exhibit excess cool gas approaching what is reported previously at z~2. Moreover, 30-40 percent of the MgII absorption occurs at radial velocities of |Delta_v_|>300km/s from the quasar, inconsistent with gas bound to a typical quasar host halo. The large velocity offsets and observed luminosity dependence of the cool gas near quasars can be explained if the gas arises from: (1) neighbouring haloes correlated through large-scale structure at Mpc scales, (2) feedback from luminous quasars or (3) debris from the mergers thought to trigger luminous quasars. The first of these scenarios is in tension with the lack of correlation between quasar luminosity and clustering while the latter two make distinct predictions that can be tested with additional observations.
- ID:
- ivo://CDS.VizieR/J/MNRAS/366/267
- Title:
- Sample of galaxies near South Celestial Pole
- Short Name:
- J/MNRAS/366/267
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper reports the results of a modest redshift survey carried out, at generally low Galactic latitudes, in the vicinity of the South Celestial Pole. Target galaxies were selected as a 'representative' sample of underlying large-scale structures. Dimensions, approximate magnitudes and radial velocity measurements, are reported for 335 galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/406/1595
- Title:
- Scalelength of 30000 SDSS disc galaxies
- Short Name:
- J/MNRAS/406/1595
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Disc scalelength (h) for 30000 galaxies from the Sloan Digitized Sky Survey (SDSS) Data Release 7, in the r-band. Also included is the Asymmetry parameter for each galaxy. Virtual Observatory methods and tools were used to define, retrieve and analyze the images for this unprecedentedly large sample classified as spiral galaxies in the LEDA catalogue. These parameters are also available for all other SDSS bands (u,g,i,z), and they can be retrieved from the Author. An extensive discussion about the errors involved in the derived parameters can be found in Fathi et al. (2010MNRAS.406.1595F) and Fathi (2010ApJ...722L.120F)
- ID:
- ivo://CDS.VizieR/J/MNRAS/458/4321
- Title:
- SCUBA-2 galaxies in 850um survey
- Short Name:
- J/MNRAS/458/4321
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the properties of the galaxies selected from the deepest 850-{mu}m survey undertaken to date with (Submillimetre Common-User Bolometer Array 2) SCUBA-2 on the James Clerk Maxwell Telescope as part of the SCUBA-2 Cosmology Legacy Survey. A total of 106 sources (>5{sigma}) were uncovered at 850{mu}m from an area of ~=150 arcmin^2^ in the centre of the COSMOS/UltraVISTA/Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) field, imaged to a typical depth of {sigma}_850_~=0.25mJy. We utilize the available multifrequency data to identify galaxy counterparts for 80 of these sources (75 per cent), and to establish the complete redshift distribution for this sample, yielding . We have also been able to determine the stellar masses of the majority of the galaxy identifications, enabling us to explore their location on the star formation rate:stellar mass (SFR:M*) plane. Crucially, our new deep 850-{mu}m-selected sample reaches flux densities equivalent to SFR~=100M_{sun}_/yr, enabling us to confirm that sub-mm galaxies form the high-mass end of the 'main sequence' (MS) of star-forming galaxies at z>1.5 (with a mean specific SFR of sSFR=2.25+/-0.19Gyr^-1^ at z~=2.5). Our results are consistent with no significant flattening of the MS towards high masses at these redshifts. However, our results add to the growing evidence that average sSFR rises only slowly at high redshift, resulting in log_10_sSFR being an apparently simple linear function of the age of the Universe.
- ID:
- ivo://CDS.VizieR/J/MNRAS/379/1571
- Title:
- SCUBA Half-Degree Extragalactic Survey. IV
- Short Name:
- J/MNRAS/379/1571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the redshift distribution of the Submillimetre Common-User Bolometer Array (SCUBA) Half Degree Survey (SHADES) galaxy population based on the rest-frame radio-mm-far-infrared (FIR) colours of 120 robustly detected 850um sources in the Lockman Hole East (LH) and Subaru XMM-Newton Deep Field (SXDF). The redshift distribution derived from the full spectral energy distribution (SED) information is shown to be narrower than that determined from the radiosub-mm spectral index, as more photometric bands contribute to a higher redshift accuracy.
