- ID:
- ivo://CDS.VizieR/J/A+A/566/A140
- Title:
- Catalog of XMM X-ray galaxy groups
- Short Name:
- J/A+A/566/A140
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 129 X-ray galaxy groups, covering a redshift range 0.04<z<1.23, selected in the ~3deg^2^ part of the CFHTLS W1 field overlapping XMM observations performed under the XMM-LSS project. We carry out a statistical study of the redshift evolution out to redshift one of the magnitude gap between the first and the second brightest cluster galaxies of a well defined mass-selected group sample. We find that the slope of the relation between the fraction of groups and the magnitude gap steepens with redshift, indicating a larger fraction of fossil groups at lower redshifts. We find that 22.2+/-6% of our groups at z<=0.6 are fossil groups. We compare our results with the predictions of three semi-analytic models based on the Millennium simulation. The intercept of the relation between the magnitude of the brightest galaxy and the value of magnitude gap becomes brighter with increasing redshift. This trend is steeper than the model predictions which we attribute to the younger stellar age of the observed brightest cluster galaxies. This trend argues in favor of stronger evolution of the feedback from active galactic nuclei at z<1 compared to the models. The slope of the relation between the magnitude of the brightest cluster galaxy and the value of the gap does not evolve with redshift and is well reproduced by the models, indicating that the tidal galaxy stripping, put forward as an explanation of the occurrence of the magnitude gap, is both a dominant mechanism and sufficiently well modeled.
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- ID:
- ivo://CDS.VizieR/J/AJ/145/31
- Title:
- Catalog of X-ray selected BL Lac objects
- Short Name:
- J/AJ/145/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a catalog of 312 X-ray selected BL Lacertae objects (XBLs), optically identified through the end of 2011. It contains the names from different surveys, equatorial coordinates, redshifts, multifrequency flux values, and luminosities for each source. In addition, the different characteristics of XBLs are statistically investigated (redshift, radio/optical/X-ray luminosities, central black hole (BH) mass, synchrotron peak frequency, broadband spectral indices, optical flux variability). Their values are collected through an extensive bibliographic and database search or calculated by us. The redshifts range from 0.031 to 0.702 with a maximum of the distribution at z=0.223. The 1.4GHz luminosities of XBLs log{nu}L_{nu}_~39-42erg/s while optical V and X-ray 0.1-2.4keV bands show log{nu}L_{nu}_~43-46erg/s. The XBL hosts are elliptical galaxies with effective radii r_eff_=3.26-25.40kpc and ellipticities, {epsilon}=0.04-0.52. Their R-band absolute magnitudes M_R_ range from -21.11mag to -24.86mag with a mean value of -22.83mag. The V-R indices of the hosts span from 0.61 to 1.52 and reveal a fourth-degree polynomial relationship with z that enables us to evaluate the redshifts of five sources whose V-R indices were determined from the observations but whose redshifts values are either not found or not confirmed. The XBL nuclei show a wider range of 7.31mag for M_R_ with the highest luminosity corresponding to M_R_=-27.24mag. The masses of central BHs are found in the interval logM_BH_=7.39-9.30 solar masses (with distribution maximum at logM_BH_/M_{sun}_=8.30). The synchrotron peak frequencies are spread over the range log{nu}_peak_=14.56-19.18Hz with a peak of the distribution at log{nu}_peak_=16.60Hz. The broadband radio-to-optical ({alpha}_ro_), optical-to-X-ray ({alpha}_ox_), and radio-to-X-ray ({alpha}_rx_) spectral indices are distributed in the intervals (0.17,0.59), (0.56,1.48), and (0.41,0.75), respectively. In the optical energy range, the overall flux variability increases, on average, towards shorter wavelengths: <{Delta}m>=1.22,1.50, and 1.82mag through the R, V, B bands of Johnson-Cousins system, respectively. XBLs seem be optically less variable at the intranight timescales compared to the radio-selected BL Lacs (RBLs).
- ID:
- ivo://CDS.VizieR/J/A+A/601/A145
- Title:
- Catalogue of cluster members
- Short Name:
- J/A+A/601/A145
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The hierarchical model of structure formation is a key prediction of the {LAMBDA} cold dark matter model, which can be tested by studying the large-scale environment and the substructure content of massive galaxy clusters. We present here a detailed analysis of the clusters RXC J0225.9-4154, RXC J0528.9-3927, and RXC J2308.3-0211, as part of a sample of massive X-ray luminous clusters located at intermediate redshifts. We used a multiwavelength analysis, combining WFI photometric observations, VIMOS spectroscopy, and the X-ray surface brightness maps. We investigated the optical morphology of the clusters, we looked for significant counterparts in the residual X-ray emission, and we ran several statistical tests to assess their dynamical state. We correlated the results to define various substructure features, to study their properties, and to quantify their influence on simple dynamical mass estimators. RXC J0225.9-4154 has a bi-modal core, and two massive galaxy groups are located in its immediate surroundings; they are aligned in an elongated structure that is also detected in X-rays at the 1{sigma} level. RXC J0528.9-3927 is located in a poor environment; an X-ray centroid shift and the presence of two central BCGs provide mild evidence for a recent and active dynamical history. RXC J2308.3-0211 has complex central dynamics, and it is found at the core of a superstes-cluster. The complexity of the cluster's central dynamics reflects the richness of its large-scale environment: RXC J0225 and RXC J2308 present a mass fraction in substructures larger than the typical 5-15%, whereas the isolated cluster RXC J0528 does not have any major substructures within its virial radius. The largest substructures are found in the cluster outskirts. The optical morphology of the clusters correlates with the orientation of their BCG, and with the position of the main axes of accretion.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A166
- Title:
- Catalogue of Cosmic Filaments
- Short Name:
- J/A+A/659/A166
- Date:
- 23 Mar 2022 15:17:04
- Publisher:
- CDS
- Description:
- In this work we present a new catalogue of cosmic filaments obtained from the latest Sloan Digital Sky Survey (SDSS) public data. In order to detect filaments, we implement a version of the Subspace-Constrained Mean-Shift algorithm that is boosted by machine learning techniques. This allows us to detect cosmic filaments as one-dimensional maxima in the galaxy density distribution. Our filament catalogue uses the cosmological sample of SDSS, including Data Release 16, and therefore inherits its sky footprint (aside from small border effects) and redshift coverage. In particular, this means that, taking advantage of the quasar sample, our filament reconstruction covers redshifts up to z=2.2, making it one of the deepest filament reconstructions to our knowledge. We follow a tomographic approach and slice the galaxy data in 269 shells at different redshift. The reconstruction algorithm is applied to 2D spherical maps. The catalogue provides the position and uncertainty of each detection for each redshift slice. The quality of our detections, which we assess with several metrics, show improvement with respect to previous public catalogues obtained with similar methods. We also detect a highly significant correlation between our filament catalogue and galaxy cluster catalogues built from microwave observations of the Planck Satellite and the Atacama Cosmology Telescope.
- ID:
- ivo://CDS.VizieR/J/ApJS/256/4
- Title:
- Catalogue of galaxies observed with Hectospec
- Short Name:
- J/ApJS/256/4
- Date:
- 03 Dec 2021 00:37:37
- Publisher:
- CDS
- Description:
- We present redshifts for 2753 low-redshift (0.05~<z_spec_~<0.5) galaxies with 18<=r<=22 obtained with Hectospec at the Multi-Mirror Telescope (MMT). The observations targeted the XMM-LSS, ELAIS-N1 and DEEP2-3 fields, each of which covers ~1deg^2^. These fields are also part of the recently completed CFHT Large Area U-band Deep Survey (CLAUDS) and on-going Hyper Suprime-Cam deep fields surveys. The efficiency of our technique for selecting low-redshift galaxies is confirmed by the redshift distribution of our sources. In addition to redshifts, these high S/N spectra are used to measure ages, metallicities, and nuclear activity levels. In combination with the photometric catalogue in u, g, r, i, z, y down to 27 AB mag, we are able to study the galaxy population down to stellar masses of ~10^8^M_{sun}_ . This paper presents the observation strategy, the reduction procedure and properties of the galaxy sample. The catalog can be accessed through the webpage of this survey http://mips.as.arizona.edu/~cnaw/Faint_Low_z/.
- ID:
- ivo://CDS.VizieR/J/A+A/606/A122
- Title:
- Catalogue of X-ray luminous clusters members
- Short Name:
- J/A+A/606/A122
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A robust determination of galaxy cluster mass is crucial to use them as cosmological probes, or to study the physics governing their formation and evolution. Applying various estimators on well-defined cluster samples is a mandatory step in characterising their respective systematics. Our main goal is to compare the results of three dynamical mass estimators to the X-ray hydrostatic values. Here we focus on massive galaxy clusters at intermediate redshifts z~0.3. We estimated dynamical masses with the virial theorem, the Jeans equation, and the caustic method using wide-field VIMOS spectroscopy; the hydrostatic masses were obtained previously from XMM-Newton observations.We investigated the role of colour selection and the impact of substructures on the dynamical estimators.
177. 3C 236 CO maps
- ID:
- ivo://CDS.VizieR/J/A+A/549/A58
- Title:
- 3C 236 CO maps
- Short Name:
- J/A+A/549/A58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- There is growing observational evidence of active galactic nuclei (AGN) feedback on the ISM of radio-quiet and radio-loud galaxies. While AGN feedback is expected to be more common at high redshift objects, the study of local universe galaxies help to better characterize the different manifestations of AGN feedback.AIMS. Molecular line observations can be used to quantify the mass and energy budget of the gas affected by AGN feedback. We study the emission of molecular gas in 3C 236, a Faranoff-Riley type 2 (FR II) radio source at z~0.1, and search for the footprints of AGN feedback. 3C 236 shows signs of a reactivation of its AGN triggered by a recent minor merger episode. Observations have also previously identified an extreme HI outflow in this source. The IRAM Plateau de Bure interferometer (PdBI) has been used to study the distribution and kinematics of molecular gas in 3C 236 by imaging with high spatial resolution (0.6") the emission of the 2-1 line of ^12^CO in the nucleus of the galaxy. We have searched for outflow signatures in the CO map. We have also derived the star-formation rate (SFR) in 3C 236 using data available from the literature at UV, optical and IR wavelengths, to determine the star-formation efficiency of molecular gas. The CO emission in 3C 236 comes from a spatially resolved ~1.4" (2.6kpc)-diameter disk characterized by a regular rotating pattern. Within the limits imposed by the sensitivity and velocity coverage of the CO data, we do not detect any outflow signatures in the cold molecular gas. The disk has a cold gas mass M(H_2_)~2.1x10^9^M_{sun}_. Based on CO we determine a new value for the redshift of the source z_CO_=0.09927+/-0.0002. The similarity between the CO and HI profiles indicates that the deep HI absorption in 3C 236 can be accounted for by a rotating HI structure. This restricts the evidence of HI outflow only to the most extreme velocities. In the light of the new redshift value, the analysis of the ionized gas kinematics reveals a fast (~1000km/s) outflow. As for the CO emitting gas, outflow signatures are nevertheless absent in the warm molecular gas emission traced by infrared H_2_ lines. The star-formation efficiency in 3C 236 is consistent with the value measured in normal galaxies, which follow the canonical Kennicutt-Schmidt (KS) relation. This result, confirmed to hold in other young radio sources examined in this work, is in stark contrast with the factor of 10-50 lower SFE that has been claimed to characterize evolved powerful radio galaxies. There are no signs of ongoing AGN feedback on the molecular ISM of 3C 236. The recent reactivation of the AGN in 3C 236 (about ~10^5^yr ago) is a likely explanation for the early evolutionary status of its molecular disk.
- ID:
- ivo://CDS.VizieR/J/ApJ/817/34
- Title:
- C-COSMOS Legacy sources multiwavelength catalog
- Short Name:
- J/ApJ/817/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalog of optical and infrared counterparts of the Chandra COSMOS-Legacy Survey, a 4.6Ms Chandra program on the 2.2deg^2^ of the COSMOS field, combination of 56 new overlapping observations obtained in Cycle 14 with the previous C-COSMOS survey. In this Paper we report the i, K, and 3.6{mu}m identifications of the 2273 X-ray point sources detected in the new Cycle 14 observations. We use the likelihood ratio technique to derive the association of optical/infrared (IR) counterparts for 97% of the X-ray sources. We also update the information for the 1743 sources detected in C-COSMOS, using new K and 3.6{mu}m information not available when the C-COSMOS analysis was performed. The final catalog contains 4016 X-ray sources, 97% of which have an optical/IR counterpart and a photometric redshift, while ~54% of the sources have a spectroscopic redshift. The full catalog, including spectroscopic and photometric redshifts and optical and X-ray properties described here in detail, is available online. We study several X-ray to optical (X/O) properties: with our large statistics we put better constraints on the X/O flux ratio locus, finding a shift toward faint optical magnitudes in both soft and hard X-ray band. We confirm the existence of a correlation between X/O and the the 2-10keV luminosity for Type 2 sources. We extend to low luminosities the analysis of the correlation between the fraction of obscured AGNs and the hard band luminosity, finding a different behavior between the optically and X-ray classified obscured fraction.
- ID:
- ivo://CDS.VizieR/J/ApJ/833/15
- Title:
- CCPC. II. 2<z<6.6 protocluster candidates
- Short Name:
- J/ApJ/833/15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Candidate Cluster and Protocluster Catalog (CCPC) is a list of objects at redshifts z>2 composed of galaxies with spectroscopically confirmed redshifts that are coincident on the sky and in redshift. These protoclusters are identified by searching for groups in volumes corresponding to the expected size of the most massive protoclusters at these redshifts. In CCPC1 we identified 43 candidate protoclusters among 14000 galaxies between 2.74<z<3.71. Here we expand our search to more than 40000 galaxies with spectroscopic redshifts z>2.00, resulting in an additional 173 candidate structures. The most significant of these are 36 protoclusters with overdensities {delta}_gal_>7. We also identify three large proto-supercluster candidates containing multiple protoclusters at z=2.3, 3.5 and z=6.56. Eight candidates with N>=10 galaxies are found at redshifts z>4.0. The last system in the catalog is the most distant spectroscopic protocluster candidate known to date at z=6.56.
- ID:
- ivo://CDS.VizieR/J/AJ/116/1529
- Title:
- cD clusters of galaxies. III.
- Short Name:
- J/AJ/116/1529
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final observational data for a spectroscopic study of a sample of cD galaxy clusters. The goal of this program has been to study the dynamics of the clusters, with emphasis on determining the nature and frequency of peculiar-velocity cD galaxies. In this paper we present redshifts for 762 galaxies in the fields of the rich Abell clusters A779, A1691, A1749, A1767, A1837, A1927, A2067, A2079, A2089, A2199, and A2666. We also present preliminary dynamical properties for these clusters using our measured redshifts.