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1181. Galaxy cluster cat. from SDSS-DR13 (GalWCat19)
ID:
ivo://CDS.VizieR/J/ApJS/246/2
Title:
Galaxy cluster cat. from SDSS-DR13 (GalWCat19)
Short Name:
J/ApJS/246/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
Utilizing the SDSS-DR13 spectroscopic data set, we create a new publicly available catalog of 1800 galaxy clusters (GalWeight cluster catalog, GalWCat19) and a corresponding catalog of 34,471 identified member galaxies. The clusters are identified from overdensities in redshift phase space. The GalWeight technique introduced by Abdullah+ (2018ApJ...861...22A) is then applied to identify cluster members. The completeness of the cluster catalog (GalWCat19) and the procedure followed to determine cluster mass are tested on the Bolshoi N-body simulations. The 1800 GalWCat19 clusters range in redshift between 0.01 and 0.2 and have masses in the range of (0.4-14)x10^14^h^-1^M_{sun}_. The cluster catalog provides a large number of cluster parameters, including sky position, redshift, membership, velocity dispersion, and mass at overdensities {Delta}=500, 200, 100, and 5.5. The 34471 member galaxies are identified within the radius at which the density is 200 times the critical density of the universe. The galaxy catalog provides the coordinates of each galaxy and the ID of the cluster that the galaxy belongs to. The cluster velocity dispersion scales with mass as log({sigma}_200_)=log(946+/-52km/s)+ (0.349+/-0.142)log[h(z)M_200_/10^1 5^M_{sun}], with a scatter of {delta}log{sigma}=0.06+/-0.04.
1182. Galaxy clusters aligned with quasars. III.
ID:
ivo://CDS.VizieR/J/ApJ/774/40
Title:
Galaxy clusters aligned with quasars. III.
Short Name:
J/ApJ/774/40
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Gemini/GMOS-S multi-object spectroscopy of 31 galaxy cluster candidates at redshifts between 0.2 and 1.0 and centered on QSO sight lines taken from Lopez et al. (Paper I, J/ApJ/679/1144). The targets were selected based on the presence of an intervening MgII absorption system at a similar redshift to that of a galaxy cluster candidate lying at a projected distance <2h_71_^-1^Mpc from the QSO sight line (a "photometric hit"). The absorption systems span rest-frame equivalent widths between 0.015 and 2.028{AA}. The general population of our confirmed absorbing galaxies have luminosities L_B_~L_B_^*^ and mean rest-frame colors (R_c_-z') typical of S_cd_ galaxies.
1183. Galaxy clusters in XMM field within CFHT-LS D4
ID:
ivo://CDS.VizieR/J/A+A/551/A8
Title:
Galaxy clusters in XMM field within CFHT-LS D4
Short Name:
J/A+A/551/A8
Date:
21 Oct 2021
Publisher:
CDS
Description:
The XMM-Newton Distant Cluster Project (XDCP) aims at the identification of a well defined sample of X-ray selected clusters of galaxies at redshifts z>0.8. As part of this project, we analyse the deep XMM-Newton exposure covering one of the CFHTLS deep fields to quantify the cluster content. We validate the optical follow-up strategy as well as the X-ray selection function. We search for extended X-ray sources in archival XMM-Newton EPIC observations. Multi-band optical imaging is performed to select high redshift cluster candidates among the extended X-ray sources. Here we present a catalogue of the extended sources in one the deepest LBQS ~250ks XMM-Newton fields targeting LBQS J2212-1759 covering ~0.2 square degrees. The cluster identification is based, among others, on deep imaging with the ESO VLT and from the CFHT legacy survey. The confirmation of cluster candidates is done by VLT/FORS2 multi-object spectroscopy. Photometric redshifts from the CFHTLS D4 are utilized to confirm the effectiveness of the X-ray cluster selection method. The survey sensitivity is computed with extensive Monte-Carlo simulations. At a flux limit of S(0.5-2.0keV)~2.5e-15erg/s/cm2 we achieve a completeness level higher than 50% in an area of ~0.13 square degrees. We detect six galaxy clusters above this limit with optical counterparts, of which 5 are new spectroscopic discoveries. Two newly discovered X-ray luminous galaxy clusters are at z>1.0, another two at z=0.41 and one at z=0.34. For the most distant X-ray selected cluster in this field at z=1.45 we find additional (active) member galaxies from both X-ray and spectroscopic data. Additionally, we find evidence of large scale structures at moderate redshifts of z=0.41 and z=0.34. The quest for distant clusters in archival XMM-Newton data has led to the detection of six clusters in a single field, making XMM-Newton an outstanding tool for cluster surveys. Three of these clusters are at z>1, which emphasises the valuable contribution of small, yet deep surveys to cosmology. Beta-models are appropriate descriptions for the cluster surface brightness to perform cluster detection simulations in order to compute the X-ray selection function. The constructed log N-log S tends to favour a scenario where no evolution in the cluster X-ray luminosity function (XLF) takes place.
1184. Galaxy cluster's rotation
ID:
ivo://CDS.VizieR/J/MNRAS/465/2616
Title:
Galaxy cluster's rotation
Short Name:
J/MNRAS/465/2616
Date:
21 Oct 2021
Publisher:
CDS
Description:
We study the possible rotation of cluster galaxies, developing, testing, and applying a novel algorithm which identifies rotation, if such does exist, as well as its rotational centre, its axis orientation, rotational velocity amplitude, and, finally, the clockwise or counterclockwise direction of rotation on the plane of the sky. To validate our algorithms we construct realistic Monte Carlo mock rotating clusters and confirm that our method provides robust indications of rotation. We then apply our methodology on a sample of Abell clusters with z<=0.1 with member galaxies selected from the Sloan Digital Sky Survey DR10 spectroscopic data base. After excluding a number of substructured clusters, which could provide erroneous indications of rotation, and taking into account the expected fraction of misidentified coherent substructure velocities for rotation, provided by our Monte Carlo simulation analysis, we find that ~23 per cent of our clusters are rotating under a set of strict criteria. Loosening the strictness of the criteria, on the expense of introducing spurious rotation indications, we find this fraction increasing to ~28 per cent. We correlate our rotation indicators with the cluster dynamical state, provided either by their Bautz-Morgan type or by their X-ray isophotal shape and find for those clusters showing rotation within 1.5h^-1^_70_ Mpc that the significance of their rotation is related to the dynamically younger phases of cluster formation but after the initial anisotropic accretion and merging has been completed. Finally, finding rotational modes in galaxy clusters could lead to the necessity of correcting the dynamical cluster mass calculations.
1185. Galaxy coordinates. II
ID:
ivo://CDS.VizieR/J/A+AS/140/89
Title:
Galaxy coordinates. II
Short Name:
J/A+AS/140/89
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using images of the Digitized Sky Survey we measured coodinates for 17298 galaxies having poorly defined coordinates. As a control, we measured with the same method 1522 galaxies having accurate coordinates. The comparison with our own measurements shows that the accuracy of the method is about 6 arcsec on each axis (RA and DEC).
1186. Galaxy distances with the Fundamental Manifold
ID:
ivo://CDS.VizieR/J/ApJ/748/15
Title:
Galaxy distances with the Fundamental Manifold
Short Name:
J/ApJ/748/15
Date:
21 Oct 2021
Publisher:
CDS
Description:
We demonstrate how the Fundamental Manifold (FM) can be used to cross-calibrate distance estimators even when those "standard candles" are not found in the same galaxy. Such an approach greatly increases the number of distance measurements that can be utilized to check for systematic distance errors and the types of estimators that can be compared. Here we compare distances obtained using Type Ia supernova (SN Ia), Cepheids, surface brightness fluctuations, the luminosity of the tip of the red giant branch, circumnuclear masers, eclipsing binaries, RR Lyrae stars, and the planetary nebulae luminosity functions. We find no significant discrepancies (differences are <2{sigma}) between distance methods, although differences at the ~10% level cannot yet be ruled out. The potential exists for significant refinement because the data used here are heterogeneous B-band magnitudes that will soon be supplanted by homogeneous, near-infrared magnitudes. We illustrate the use of FM distances to (1) revisit the question of the metallicity sensitivity of various estimators, confirming the dependence of SN Ia distances on host galaxy metallicity, and (2) provide an alternative calibration of H_0_ that replaces the classical ladder approach in the use of extragalactic distance estimators with one that utilizes data over a wide range of distances simultaneously.
1187. Galaxy environment in the 3D-HST fields (z=0.5-3)
ID:
ivo://CDS.VizieR/J/ApJ/835/153
Title:
Galaxy environment in the 3D-HST fields (z=0.5-3)
Short Name:
J/ApJ/835/153
Date:
21 Oct 2021
Publisher:
CDS
Description:
We make publicly available a catalog of calibrated environmental measures for galaxies in the five 3D-Hubble Space Telescope (HST)/CANDELS deep fields. Leveraging the spectroscopic and grism redshifts from the 3D-HST survey, multiwavelength photometry from CANDELS, and wider field public data for edge corrections, we derive densities in fixed apertures to characterize the environment of galaxies brighter than JH_140_<24mag in the redshift range 0.5<z<3.0. By linking observed galaxies to a mock sample, selected to reproduce the 3D-HST sample selection and redshift accuracy, each 3D-HST galaxy is assigned a probability density function of the host halo mass, and a probability that it is a central or a satellite galaxy. The same procedure is applied to a z=0 sample selected from Sloan Digital Sky Survey. We compute the fraction of passive central and satellite galaxies as a function of stellar and halo mass, and redshift, and then derive the fraction of galaxies that were quenched by environment specific processes. Using the mock sample, we estimate that the timescale for satellite quenching is t_quench_~2-5Gyr; it is longer at lower stellar mass or lower redshift, but remarkably independent of halo mass. This indicates that, in the range of environments commonly found within the 3D-HST sample (M_h_<~10^14^M_{sun}_), satellites are quenched by exhaustion of their gas reservoir in the absence of cosmological accretion. We find that the quenching times can be separated into a delay phase, during which satellite galaxies behave similarly to centrals at fixed stellar mass, and a phase where the star formation rate drops rapidly ({tau}_f_~0.4-0.6Gyr), as shown previously at z=0. We conclude that this scenario requires satellite galaxies to retain a large reservoir of multi-phase gas upon accretion, even at high redshift, and that this gas sustains star formation for the long quenching times observed.
1188. Galaxy groups and clouds in the local universe
ID:
ivo://CDS.VizieR/J/MNRAS/412/2498
Title:
Galaxy groups and clouds in the local universe
Short Name:
J/MNRAS/412/2498
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an all-sky catalogue of 395 nearby galaxy groups revealed in the Local Supercluster and its surroundings. The groups and their associations are identified among 10914 galaxies at |b|>15{deg} with radial velocities V_LG_<3500km/s. Our group-finding algorithm requires the group members to be located inside their zero-velocity surface. Hereby, we assume that individual galaxy masses are proportional to their total K-band luminosities, M/L_K_=6M_{sun}_/L_{sun}_. The sample of our groups, where each group has n>=4 members, is characterized by the following medians: mean projected radius <R>=268kpc, radial velocity dispersion {sigma}_V_=74km/s, K-band luminosity L_K_=1.2x10^11^L_{sun}_, virial and projected masses M_vir_=2.4x10^12^ and M_p_=3.3x10^12^M_{sun}_, respectively. Accounting for measurement error reduces the median masses by 30 per cent. For 97 per cent of identified groups the crossing time does not exceed the cosmic time, 13.7Gyr, with the median at 3.8Gyr. We examine different properties of the groups, in particular of the known nearby groups and clusters in Virgo and Fornax. About a quarter of our groups can be classified as fossil groups where the dominant galaxy is at least 10 times brighter than the other group members.
1189. Galaxy groups within 3500km/s
ID:
ivo://CDS.VizieR/J/ApJ/843/16
Title:
Galaxy groups within 3500km/s
Short Name:
J/ApJ/843/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
A study of the group properties of galaxies in our immediate neighborhood provides a singular opportunity to observationally constrain the halo mass function, a fundamental characterization of galaxy formation. Detailed studies of individual groups have provided the coefficients of scaling relations between a proxy for the virial radius, velocity dispersion, and mass that usefully allow groups to be defined over the range 10^10^-10^15^M_{sun}_. At a second hierarchical level, associations are defined as regions around collapsed halos extending to the zero-velocity surface at the decoupling from cosmic expansion. The most remarkable result of the study emerges from the construction of the halo mass function from the sample. At ~10^12^M_{sun}_, there is a jog from the expectation Sheth-Tormen function, such that halo counts drop by a factor ~3 in all lower mass bins.
1190. Galaxy luminosity function at z =~ 7
ID:
ivo://CDS.VizieR/J/MNRAS/440/2810
Title:
Galaxy luminosity function at z =~ 7
Short Name:
J/MNRAS/440/2810
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a new search for bright star-forming galaxies at redshift z=~7 within the UltraVISTA second data release (DR2) and UKIDSS (UKIRT Infrared Deep Sky Survey) UDS (Ultra Deep Survey) DR10 data, which together provide 1.65deg^2^ of near-infrared imaging with overlapping optical and Spitzer data. Using a full photometric redshift analysis, to identify high-redshift galaxies and reject contaminants, we have selected a sample of 34 luminous (-22.7<M_UV_<-21.2) galaxies with 6.5<z<7.5. Crucially, the deeper imaging provided by UltraVISTA DR2 confirms all of the robust objects previously uncovered by Bowler et al., validating our selection technique. Our new expanded galaxy sample includes the most massive galaxies known at z=~7, with M*=~10^10^M_{sun}_, and the majority are resolved, consistent with larger sizes (r_1/2_=~1-1.5kpc) than displayed by less massive galaxies. From our final robust sample, we determine the form of the bright end of the rest-frame UV galaxy luminosity function (LF) at z=~7, providing strong evidence that it does not decline as steeply as predicted by the Schechter-function fit to fainter data. We exclude the possibility that this is due to either gravitational lensing, or significant contamination of our galaxy sample by active galactic nuclei (AGN). Rather, our results favour a double power-law form for the galaxy LF at high redshift, or, more interestingly, an LF which simply follows the form of the dark matter halo mass function at bright magnitudes. This suggests that the physical mechanism which inhibits star formation activity in massive galaxies (i.e. AGN feedback or some other form of 'mass quenching') has yet to impact on the observable galaxy LF at z=~7, a conclusion supported by the estimated masses of our brightest galaxies which have only just reached a mass comparable to the critical 'quenching mass' of M*=~10^10.2^M_{sun}_ derived from studies of the mass function of star-forming galaxies at lower redshift.