- ID:
- ivo://CDS.VizieR/J/A+A/527/A90
- Title:
- WSRT Virgo HI filament survey
- Short Name:
- J/A+A/527/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of neutral hydrogen can provide a wealth of information about the kinematics of galaxies. To learn more about the large-scale structures and accretion processes, the extended environment of galaxies have to be observed. Numerical simulations predict a cosmic web of extended structures and gaseous filaments. To observe the direct vicinity of galaxies, column densities have to be achieved that probe the regime of Lyman limit systems. Typically, HI observations are limited to a brightness sensitivity of N_HI_~10^19^cm^-2^, but this has to be improved by ~2 orders of magnitude. With the Westerbork Synthesis Radio Telescope (WSRT), we mapped the galaxy filament connecting the Virgo Cluster with the Local Group. About 1500 square degrees on the sky was surveyed with Nyquist sampled pointings. By using the WSRT antennas as single-dish telescopes instead of the more conventional interferometer, we were very sensitive to extended emission. The survey consists of a total of 22000 pointings, and each pointing was observed for two minutes with 14 antennas.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/528/A28
- Title:
- WSRT Virgo HI filament survey. II.
- Short Name:
- J/A+A/528/A28
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The extended environment of galaxies contains a wealth of information about the formation and life cycle of galaxies which are regulated by accretion and feedback processes. Observations of neutral hydrogen are routinely used to image the high brightness disks of galaxies and to study their kinematics. Deeper observations will give more insight into the distribution of diffuse gas in the extended halo of the galaxies and the inter-galactic medium, where numerical simulations predict a cosmic web of extended structures and gaseous filaments. To observe the extended environment of galaxies, column density sensitivities have to be achieved that probe the regime of Lyman limit systems. HI observations are typically limited to a brightness sensitivity of NHI~10^19^cm^-2^, but this must be improved upon by ~2 orders of magnitude.
- ID:
- ivo://CDS.VizieR/J/MNRAS/460/923
- Title:
- WSRT ZoA Perseus-Pisces. HI catalogue
- Short Name:
- J/MNRAS/460/923
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a blind 21cm HI-line imaging survey of a galaxy overdensity located behind the Milky Way at l, b ~= 160{deg}, 0.5{deg}. The overdensity corresponds to a zone-of-avoidance crossing of the Perseus-Pisces Supercluster filament. Although it is known that this filament contains an X-ray galaxy cluster (3C 129) hosting two strong radio galaxies, little is known about galaxies associated with this potentially rich cluster because of the high Galactic dust extinction. We mapped a sky area of ~9.6 deg^2^ using the Westerbork Synthesis Radio Telescope in a hexagonal mosaic of 35 pointings observed for 12h each, in the radial velocity range cz=2400-16600km/s. The survey has a sensitivity of 0.36mJy/beam rms at a velocity resolution of 16.5km/s. We detected 211 galaxies, 62 per cent of which have a near-infrared counterpart in the UKIDSS Galactic Plane Survey. We present a catalogue of the HI properties and an HI atlas containing total intensity maps, position-velocity diagrams, global HI profiles and UKIDSS counterpart images. For the resolved galaxies we also present HI velocity fields and radial HI surface density profiles. A brief analysis of the structures outlined by these galaxies finds that 87 of them lie at the distance of the Perseus-Pisces Supercluster (cz~4000-8000km/s) and seem to form part of the 3C 129 cluster. Further 72 detections trace an overdensity at a velocity of cz~=10000km/s and seem to coincide with a structure predicted from mass density reconstructions in the first 2MASS Redshift Survey.
- ID:
- ivo://CDS.VizieR/J/ApJS/247/43
- Title:
- WWFI g'-band obs. of bright cluster galaxies
- Short Name:
- J/ApJS/247/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Observations of 170 local (z<~0.08) galaxy clusters in the northern hemisphere have been obtained with the Wendelstein Telescope Wide Field Imager (WWFI). We correct for systematic effects such as point-spread function broadening, foreground star contamination, relative bias offsets, and charge persistence. Background inhomogeneities induced by scattered light are reduced down to {Delta}SB>31 g' mag/arcsec^2^ by large dithering and subtraction of night-sky flats. Residual background inhomogeneities brighter than SB_{sigma}_<27.6 g' mag/arcsec^2^ caused by galactic cirrus are detected in front of 23% of the clusters. However, the large field of view allows discrimination between accretion signatures and galactic cirrus. We detect accretion signatures in the form of tidal streams in 22%, shells in 9.4%, and multiple nuclei in 47% of the brightest cluster galaxies (BCGs) and find two BCGs in 7% of the clusters. We measure semimajor-axis surface brightness profiles of the BCGs and their surrounding intracluster light (ICL) down to a limiting surface brightness of SB=30 g' mag/arcsec^2^. The spatial resolution in the inner regions is increased by combining the WWFI light profiles with those that we measured from archival Hubble Space Telescope images or deconvolved WWFI images. We find that 71% of the BCG+ICL systems have surface brightness (SB) profiles that are well described by a single Sersic function, whereas 29% require a double Sersic function to obtain a good fit. We find that BCGs have scaling relations that differ markedly from those of normal ellipticals, likely due to their indistinguishable embedding in the ICL.
- ID:
- ivo://CDS.VizieR/J/ApJS/252/27
- Title:
- WWFI g'-band obs. of bright galaxy clusters
- Short Name:
- J/ApJS/252/27
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore several ways to dissect brightest cluster galaxies (BCGs) and their surrounding intracluster light (ICL) using a surface brightness (SB) cut, a luminosity cut, excess light above a de Vaucouleurs profile, or a double Sersic decomposition. Assuming that all light above M{<}-21.85g'mag is attributable to the ICL, we find that an average fraction of f_ICL_^MT^=71+/-22% of all diffuse light centered on the BCG belongs to the ICL. Likewise, if we assume that all light fainter than SB>27g'mag/arcsec^2^ belongs to the ICL, the average ICL fraction is f_ICL_^SB27^=34+/-19% . After fitting a de Vaucouleurs profile to the inner parts of the SB profile, we detect excess light at large radii, corresponding to an average ICL fraction of f_ICL_^DV^=48+/-20% . Finally, by decomposing the SB profile into two Sersic functions, we find an average ICL fraction of f_ICL_^Sx^=52+/-21% associated with the outer Sersic component. Our measured ICL and BCG+ICL luminosities agree well with predictions from high-resolution simulations where the outer Sersic component traces the unrelaxed, accreted stellar material. BCG and ICL properties defined in this way are correlated with cluster parameters to study the coevolution of BCGs, ICL, and their host clusters. We find positive correlations between BCG+ICL brightness and cluster mass, cluster velocity dispersion, cluster radius, and integrated satellite brightness, confirming that BCG/ICL growth is indeed coupled with cluster growth. On average, the ICL is better aligned than the BCG with the host cluster in terms of position angle, ellipticity, and centering. That makes it a potential dark-matter tracer.
1166. XBACs, the sample
- ID:
- ivo://CDS.VizieR/J/MNRAS/281/799
- Title:
- XBACs, the sample
- Short Name:
- J/MNRAS/281/799
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an essentially complete, all-sky, X-ray flux-limited sample of 242 Abell clusters of galaxies (six of which are double) compiled from ROSAT All-Sky Survey data. Our sample is uncontaminated in the sense that systems featuring prominent X-ray point sources such as AGN or foreground stars have been removed. The sample is limited to high Galactic latitudes (|b|>=20{deg}), the nominal redshift range of the ACO catalogue of z<=0.2, and X-ray fluxes above 5.0x10^-12^erg/cm^2^/s in the 0.1-2.4keV band. Owing to the X-ray flux limit, our sample consists, at intermediate and high redshifts, exclusively of very X-ray-luminous clusters. Since the latter tend to be also optically rich, the sample is not affected by the optical selection effects and, in particular, not by the volume incompleteness known to be present in the Abell and ACO catalogues for richness class 0 and 1 clusters. Our sample is the largest X-ray flux-limited sample of galaxy clusters compiled to date and will allow investigations of unprecedented statistical quality into the properties and distribution of rich clusters in the local Universe.
1167. X-CLASS/GROND catalogue
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/662
- Title:
- X-CLASS/GROND catalogue
- Short Name:
- J/MNRAS/468/662
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The XMM Cluster Archive Super Survey (X-CLASS) is a serendipitously detected X-ray-selected sample of 845 galaxy clusters based on 2774 XMM archival observations and covering an approximately 90deg^2^ spread across the high-Galactic latitude (|b|>20{deg}) sky. The primary goal of this survey is to produce a well-selected sample of galaxy clusters on which cosmological analyses can be performed. This paper presents the photometric redshift follow-up of a high signal-to-noise ratio subset of 265 of these clusters with declination {delta}<+20{deg} with Gamma-Ray Burst Optical and Near-Infrared Detector (GROND), a 7-channel (grizJHK) simultaneous imager on the MPG 2.2-m telescope at the ESO La Silla Observatory. We use a newly developed technique based on the red sequence colour-redshift relation, enhanced with information coming from the X-ray detection to provide photometric redshifts for this sample. We determine photometric redshifts for 232 clusters, finding a median redshift of z=0.39 with an accuracy of {Delta}z=0.02(1+z) when compared to a sample of 76 spectroscopically confirmed clusters. We also compute X-ray luminosities for the entire sample and find a median bolometric luminosity of 7.2x10^43^erg/s and a median temperature of 2.9 keV. We compare our results to those of the XMM-XCS and XMM-XXL surveys, finding good agreement in both samples. The X-CLASS catalogue is available online at http://xmm-lss.in2p3.fr:8080/l4sdb/.
- ID:
- ivo://CDS.VizieR/J/A+A/568/A5
- Title:
- XDCP J0044.0-2033 J and Ks images
- Short Name:
- J/A+A/568/A5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent observational progress has enabled the detection of galaxy clusters and groups out to very high redshifts and for the first time allows detailed studies of galaxy population properties in these densest environments in what was formerly known as the "redshift desert" at z>1.5. We aim to investigate various galaxy population properties of the massive X-ray luminous galaxy cluster XDCP J0044.0-2033 at z=1.58, which constitutes the most extreme currently known matter-density peak at this redshift. We analyzed deep VLT/HAWK-I near-infrared data with an image quality of 0.5" and limiting Vega magnitudes (50% completeness) of 24.2 in J- and 22.8 in the Ks band, complemented by similarly deep Subaru imaging in i and V, Spitzer observations at 4.5um, and new spectroscopic observations with VLT/FORS 2.
- ID:
- ivo://CDS.VizieR/J/ApJS/172/182
- Title:
- XMM Clusters of galaxies in COSMOS field
- Short Name:
- J/ApJS/172/182
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a search for galaxy clusters in the first 36 XMM-Newton pointings on the Cosmic Evolution Survey (COSMOS) field. We reach a depth for a total cluster flux in the 0.5-2keV band of 3x10^-15^ergs/cm^2^/s, having one of the widest XMM-Newton contiguous raster surveys, covering an area of 2.1deg^2^. Cluster candidates are identified through a wavelet detection of extended X-ray emission. Verification of the cluster candidates is done based on a galaxy concentration analysis in redshift slices of thickness 0.1-0.2 in redshift, using the multiband photometric catalog of the COSMOS field and restricting the search to z<1.3 and i_AB_<25. We identify 72 clusters and derive their properties based on the X-ray cluster scaling relations. A statistical description of the survey in terms of the cumulative log(N>S)-logS distribution compares well with previous results, although yielding a somewhat higher number of clusters at similar fluxes. The X-ray luminosity function of COSMOS clusters matches well the results of nearby surveys, providing a comparably tight constraint on the faint-end slope of alpha=1.93+/-0.04. For the probed luminosity range of (8x10^42^)-(2x10^44^)ergs/s, our survey is in agreement with and adds significantly to the existing data on the cluster luminosity function at high redshifts and implies no substantial evolution at these luminosities to z=1.3.
- ID:
- ivo://CDS.VizieR/J/MNRAS/382/279
- Title:
- XMM-LSS catalogue. Version I.
- Short Name:
- J/MNRAS/382/279
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide the source list for the first 5.5 surveyed square degrees of the XMM-LSS, with a total of 3385 point-like or extended sources above a detection likelihood of 15 in either 0.5-2 or 2-10keV bands. The table at CDS contains the main parameters, while further parameters and data products (X-ray images and optical thumbnails) are available in the Milan XMM-LSS database site.
