- ID:
- ivo://CDS.VizieR/J/AN/327/365
- Title:
- Clusters and groups of galaxies in 2dF
- Short Name:
- J/AN/327/365
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We create a new catalogue of groups and clusters, applying the friends-to-friends method to the 2dF GRS final release. We investigate various selection effects due to the use of a magnitude limited sample. For this purpose we follow the changes in group sizes and mean galaxy number densities within the groups when shifting nearby observed groups to larger distances. We study the distribution of sizes of dark matter haloes in N-body simulations and compare properties of these haloes and the 2dF groups.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/259/233
- Title:
- Cluster SC2008-57(A3667)
- Short Name:
- J/MNRAS/259/233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (Abstract of the paper) We present the results of photometric and spectroscopic observations of the cluster of galaxies SC2008-57 (A3667). The observations have resulted in a catalogue with positions and magnitudes for 203 galaxies, complete at b_25 = 18.0, and radial velocities for 128 galaxies, 91 per cent complete at b_25 = 17.5. The cluster can be classified as type L because its galaxy distribution is highly flattened. It shows two strong concentrations: a main concentration, centred on the cluster brightest galaxy (a D galaxy) and coincident with the peak of X-ray emission, and a substructure around the second brightest galaxy (also a D galaxy). Most of the galaxies in this substructure seem to be bound to the second-brightest galaxy, forming a dynamical subunit inside the cluster. The extreme flattening of the cluster may at least partially be due to the presence of the substructure. The cluster also shows evidence for luminosity segregation, with the brightest galaxies being preferentially found in high galaxy density regions. Most of the luminosity segregation, however, is produced by galaxies associated with the two clumps around the D galaxies, suggesting that dynamical friction is effective in subclusters with low velocity dispersions and may be associated with the formation of D galaxies. The velocity dispersion of SC2008-57 is high, about 1200 km/s, but consistent with the observed X-ray luminosity. The cluster mass, derived using several estimators, is about 2.6 x 10^15 M_solar. Both the cluster mass and velocity dispersion may be overestimates due to the presence of the substructure.
- ID:
- ivo://CDS.VizieR/J/A+A/616/A42
- Title:
- Clusters candidates from PSZ1 catalogue
- Short Name:
- J/A+A/616/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have identified new clusters and characterized previously unknown Planck Sunyaev-Zeldovich (SZ) sources from the first Planck catalogue of SZ sources (PSZ1). The results presented here correspond to an optical follow-up observational programme developed during approximately one year (2014) at Roque de los Muchachos Observatory, using the 2.5m Isaac Newton telescope, the 3.5m Telescopio Nazionale Galileo, the 4.2m William Herschel telescope and the 10.4m Gran Telescopio Canarias. We have characterized 115 new PSZ1 sources using deep optical imaging and spectroscopy. We adopted robust criteria in order to consolidate the SZ counterparts by analysing the optical richness, the 2D galaxy distribution, and velocity dispersions of clusters. Confirmed counterparts are considered to be validated if they are rich structures, well aligned with the Planck PSZ1 coordinate and show relatively high velocity dispersion. Following this classification, we confirm 53 clusters, which means that 46% of this PSZ1 subsample has been validated and characterized with this technique. Sixty-two SZ sources (54% of this PSZ1 subset) remain unconfirmed. In addition, we find that the fraction of unconfirmed clusters close to the galactic plane (at |b|<25{deg}) is greater than that at higher galactic latitudes (|b|>25{deg}), which indicates contamination produced by radio emission of galactic dust and gas clouds on these SZ detections. In fact, in the majority of the cases, we detect important galactic cirrus in the optical images, mainly in the SZ target located at low galactic latitudes, which supports this hypothesis.
- ID:
- ivo://CDS.VizieR/J/ApJS/199/34
- Title:
- Clusters of galaxies in SDSS-III
- Short Name:
- J/ApJS/199/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the photometric redshifts of galaxies from the Sloan Digital Sky Survey III (SDSS-III), we identify 132684 clusters in the redshift range of 0.05<=z<0.8. Monte Carlo simulations show that the false detection rate is less than 6% for the whole sample. The completeness is more than 95% for clusters with a mass of M_200_>1.0x10^14^M_{sun}_ in the redshift range of 0.05<=z<0.42, while clusters of z>0.42 are less complete and have a biased smaller richness than the real one due to incompleteness of member galaxies. We compare our sample with other cluster samples, and find that more than 90% of previously known rich clusters of 0.05<=z<0.42 are matched with clusters in our sample. Richer clusters tend to have more luminous brightest cluster galaxies (BCGs). Correlating with X-ray and the Planck data, we show that the cluster richness is closely related to the X-ray luminosity, temperature, and Sunyaev-Zel'dovich measurements. Comparison of the BCGs with the SDSS luminous red galaxy (LRG) sample shows that 25% of LRGs are BCGs of our clusters and 36% of LRGs are cluster member galaxies. In our cluster sample, 63% of BCGs of r_petro_<19.5 satisfy the SDSS LRG selection criteria.
- ID:
- ivo://CDS.VizieR/J/A+AS/110/313
- Title:
- Clusters of galaxies properties. II.
- Short Name:
- J/A+AS/110/313
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present F band photometry, from digitized 48-inch Palomar plates, of 1167 galaxies brighter than m_3_ +3 in 10 Abell clusters. For each galaxy, absolute coordinates, magnitude, size, ellipticity and orientation are given. For each cluster we provide finding charts and contour maps of the galaxy surface density.
- ID:
- ivo://CDS.VizieR/J/A+A/286/17
- Title:
- 21cm obs. of galaxies in Psc-Per Supercl.
- Short Name:
- J/A+A/286/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the first results of a 21cm survey of newly discovered optically selected galaxies behind the Milky Way. We present 40 radial velocities of the new galaxies and 15 velocities of UGC and MCG galaxies in a region where the well known Pisces-Perseus-Supercluster (PPScl) is supposed to be veiled by galactic extinction (80deg<~l<~110deg). Twenty-four galaxies have radial velocities between 4000 and 6000 km/s that fit to the values usually accepted for the PPScl. We could pursue this supercluster at least to b=-5 deg around l=90 deg.
- ID:
- ivo://CDS.VizieR/J/MNRAS/324/1131
- Title:
- 22-cm radio survey of A3528
- Short Name:
- J/MNRAS/324/1131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report and discuss the results of a 22-cm radio survey carried out with the Australia Telescope Compact Array (ATCA) covering the A3528 complex, a chain formed by the merging ACO clusters A3528-A3530-A3532, located in the central region of the Shapley Concentration. Simultaneous 13-cm observations are also presented. Our final catalogue includes a total of 106 radio sources above the flux density limit of 0.8mJy. By cross-correlation with optical and spectroscopic catalogues we found 32 optical counterparts, nine of them belonging to the A3528 complex.
218. 21 cm Spectra
- ID:
- ivo://CDS.VizieR/J/AJ/113/1197
- Title:
- 21 cm Spectra
- Short Name:
- J/AJ/113/1197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A compilation of H I line fluxes, systemic velocities and linewidths is presented for 840 detected galaxies, mostly in the vicinities of 30 nearby rich clusters out to a redshift of z~0.04, specifically for use in applications of the Tully-Fisher distance method. New 21 cm H I line profiles have been obtained for ~500 galaxies in 27 Abell clusters visible from Arecibo. Upper limits are also presented for 246 galaxies for which H I emission was not detected. In order to provide a homogeneous linewidth determination optimized for Tully-Fisher studies, these new data are supplemented by the reanalysis of previously published spectra obtained both at Arecibo and Green Bank that are available in a digital archive. Corrections for instrumental broadening, smoothing, signal-to-noise and profile shape are applied, and an estimate of the error on the width is given. When corrected for turbulent broadening and viewing angle, the corrected velocity widths presented here will provide the appropriate line width parameter needed to derive distances via the Tully-Fisher relation.
- ID:
- ivo://CDS.VizieR/J/ApJS/116/247
- Title:
- CNOC cluster redshift survey catalogs. VI.
- Short Name:
- J/ApJS/116/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A photometric and redshift catalog of galaxies in the field of two rich galaxy clusters, MS 0015.9+1609 (z=0.5481) and MS 0451.5-0305 (z=0.5386), is presented as part of the Canadian Network for Observation Cosmology (CNOC) cluster redshift survey carried out at the Canada-France-Hawaii Telescope (CFHT) using the MOS imaging multiobject spectrograph. The imaging and spectroscopic observations cover a single field of approximately 7.6'x9.1', centered on each cluster. Redshifts for 247 galaxies, primarily ranging in magnitude from r=20 to r=22, were obtained. The data set is also presented graphically in several forms. The magnitude, color, and geometric selection functions for the redshift sample are presented and discussed.
- ID:
- ivo://CDS.VizieR/J/A+A/638/A114
- Title:
- CODEX galaxy clusters catalog
- Short Name:
- J/A+A/638/A114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Large area catalogs of galaxy clusters constructed from ROSAT All Sky Survey provide the base for our knowledge on the population of clusters thanks to the long-term multiwavelength efforts to follow-up observations of these clusters.. Advent of large area photometric surveys superseding in depth previous all-sky data allows us to revisit the construction of X-ray cluster catalogs, extending the study to lower cluster masses and to higher redshifts and to provide the modelling of the selection function. We perform a wavelet detection of X-ray sources and make extensive simulations of the detection of clusters in the RASS data. We assign an optical richness to each of the 24,788 detected X-ray sources in the 10,382 square degrees of SDSS BOSS area, using redMaPPer version 5.2 run on Sloan Digital Sky Survey photometry. We name this survey COnstrain Dark Energy with X-ray (CODEX) clusters. We show that there is no obvious separation of sources on galaxy clusters and AGN, based on distribution of systems on their richness. This is a combination of increasing number of galaxy groups and their selection as identification of an X-ray sources either by chance or due to groups hosting an AGN. To clean the sample, we use a cut on the optical richness at the level corresponding to the 10% completeness of the survey and include it into the modelling of cluster selection function. We present the X-ray catalog extending to a redshift of 0.6. CODEX is the first large area X-ray selected catalog of Northern clusters reaching the fluxes of 10^-13^ergs/s/cm^2^. We provide the modelling of the sample selection and discuss the redshift evolution of the high end of the X-ray luminosity function (XLF). Our results on z<0.3 XLF are in agreement with previous studies, while we provide new constraints on the 0.3<z<0.6 XLF. We find a lack of strong redshift evolution of the XLF, provide exact modeling of the effect of low number statistics and AGN contamination and present the resulting constraints on the flat {LAMBDA}CDM.
