- ID:
- ivo://CDS.VizieR/J/ApJ/812/34
- Title:
- Properties of UCD candidates in M87/M49/M60 regions
- Short Name:
- J/ApJ/812/34
- Date:
- 14 Jan 2022 08:28:26
- Publisher:
- CDS
- Description:
- We use imaging from the Next Generation Virgo cluster Survey (NGVS) to present a comparative study of ultra-compact dwarf (UCD) galaxies associated with three prominent Virgo sub-clusters: those centered on the massive red-sequence galaxies M87, M49, and M60. We show how UCDs can be selected with high completeness using a combination of half-light radius and location in color-color diagrams (u*iK_s_ or u*gz). Although the central galaxies in each of these sub-clusters have nearly identical luminosities and stellar masses, we find large differences in the sizes of their UCD populations, with M87 containing ~3.5 and 7.8 times more UCDs than M49 and M60, respectively. The relative abundance of UCDs in the three regions scales in proportion to sub-cluster mass, as traced by X-ray gas mass, total gravitating mass, number of globular clusters (GCs), and number of nearby galaxies. We find that the UCDs are predominantly blue in color, with ~85% of the UCDs having colors similar to blue GCs and stellar nuclei of dwarf galaxies. We present evidence that UCDs surrounding M87 and M49 may follow a morphological sequence ordered by the prominence of their outer, low surface brightness envelope, ultimately merging with the sequence of nucleated low-mass galaxies, and that envelope prominence correlates with distance from either galaxy. Our analysis provides evidence that tidal stripping of nucleated galaxies is an important process in the formation of UCDs.
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- ID:
- ivo://CDS.VizieR/J/A+A/620/A186
- Title:
- Properties of VIS3COS galaxies
- Short Name:
- J/A+A/620/A186
- Date:
- 02 Mar 2022 11:37:55
- Publisher:
- CDS
- Description:
- We present the VIMOS Spectroscopic Survey of a Supercluster in the COSMOS field (VIS^3^COS) at z~0.84. We use VIMOS high-resolution spectra (GG475 filter) to spectroscopically select 490 galaxies in and around the superstructure and an additional 481 galaxies in the line of sight. We present the redshift distribution, the catalogue to be made public, and the first results on the properties of individual galaxies and stacked spectra (3500{AA}<{lambda}<4200{AA} rest-frame). We probe a wide range of densities and environments (from low-density field to clusters and rich groups). We find a decrease in the median star formation rate from low- to high-density environments in all bins of stellar mass and a sharp rise of the quenched fraction {(from ~10% to ~40-60%)} of intermediate-stellar-mass galaxies (10<log_10_M*/M_{sun}_)<10.75) from filaments to clusters. The quenched fraction for massive galaxies shows little dependence on environment, being constant at ~30-40%. We find a break in the strength of the [OII] emission, with nearly constant line equivalent widths at lower densities (~-11{AA}) and then a drop to ~-2.5{AA} towards higher densities. The break in the [OII] line strength happens at similar densities (log_10_(1+{delta})~0.0-0.5) as the observed rise in the quenched fraction. Our results may provide further clues regarding the different environmental processes affecting galaxies with different stellar masses and highlight the advantages of a single dataset in the COSMOS field probing a wide range of stellar masses and environments. We hypothesise that quenching mechanisms are enhanced in high-density regions.
- ID:
- ivo://CDS.VizieR/J/MNRAS/468/4006
- Title:
- Proto-cluster candidate fields
- Short Name:
- J/MNRAS/468/4006
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present SCUBA-2 follow-up of 61 candidate high-redshift Planck sources. Of these, 10 are confirmed strong gravitational lenses and comprise some of the brightest such submm sources on the observed sky, while 51 are candidate proto-cluster fields undergoing massive starburst events. With the accompanying Herschel-Spectral and Photometric Imaging Receiver observations and assuming an empirical dust temperature prior of 34^+13^_-9_K, we provide photometric redshift and far-IR luminosity estimates for 172 SCUBA-2-selected sources within these Planck overdensity fields. The redshift distribution of the sources peak between a redshift of 2 and 4, with one-third of the sources having S_500_/S_350_>1. For the majority of the sources, we find far-IR luminosities of approximately 10^13^L_{sun}_, corresponding to star formation rates of around 1000M_{sun}_/yr. For S_850_>8mJy sources, we show that there is up to an order of magnitude increase in star formation rate density and an increase in uncorrected number counts of 6 for S_850_>8mJy when compared to typical cosmological survey fields. The sources detected with SCUBA-2 account for only approximately 5 per cent of the Planck flux at 353 GHz, and thus many more fainter sources are expected in these fields.
- ID:
- ivo://CDS.VizieR/J/MNRAS/432/62
- Title:
- PS1 MDS X-ray selected galaxy clusters
- Short Name:
- J/MNRAS/432/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a pilot study for the extended Massive Cluster Survey (eMACS), a comprehensive search for distant, X-ray luminous galaxy clusters at z>0.5. Our pilot study applies the eMACS concept to the 71deg^2^ area extended by the 10 fields of the Pan-STARRS1 (PS1) Medium Deep Survey (MDS). Candidate clusters are identified by visual inspection of PS1 images in the g, r, i and z bands in a 5x5arcmin^2^ region around X-ray sources detected in the ROSATAll-Sky Survey (RASS).
- ID:
- ivo://CDS.VizieR/J/A+A/628/A13
- Title:
- PSZ2 cluster candidates. I.
- Short Name:
- J/A+A/628/A13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Aims. The second catalogue of Planck Sunyaev-Zeldovich (SZ) sources, hereafter PSZ2, is the largest sample of galaxy clusters selected through their SZ signature in the full sky. At the time of publication, 21% of these objects had no known counterpart at other wavelengths. Using telescopes at the Canary Island observatories, we conducted the long-term observational programme 128-MULTIPLE-16/15B (hereafter LP15), a large and complete optical follow-up campaign of all the unidentified PSZ2 sources in the northern sky, with declinations above -15{deg} and no correspondence in the first Planck catalogue PSZ1. The main aim of LP15 is to validate all those SZ cluster candidates, and to contribute to the characterization of the actual purity and completeness of full Planck SZ sample. In this paper, we describe the full programme and present the results of the first year of observations. Methods. The LP15 programme was awarded 44 observing nights, spread over two years in three telescopes at the Roque de los Muchachos Observatory. The full LP15 sample comprises 190 previously unidentified PSZ2 sources. For each target, we performed deep optical imaging and spectroscopy. Our validation procedure combined this optical information with SZ emission as traced by the publicly available Planck Compton y-maps. The final classification of the new galaxy clusters as optical counterparts of the SZ signal is established according to several quantitative criteria based on the redshift, velocity dispersion, and richness of the clusters. Results. This paper presents the detailed study of 106 objects out of the LP15 sample, corresponding to all the observations carried out during the first year of the programme. We confirmed the optical counterpart for 41 new PSZ2 sources, 31 of them being validated using also velocity dispersion based on our spectroscopic information. This is the largest dataset of newly confirmed PSZ2 sources without any previous optical information. All the confirmed counterparts are rich structures (i.e. they show high velocity dispersion), and are well aligned with the nominal Planck coordinates (i.e. ~70% of them are located at less than 3' distance). In total, 65 SZ sources are classified as unconfirmed, 57 of them being due to the absence of an optical over-density, and eight of them due to a weak association with the observed SZ decrement. Most of the sources with no optical counterpart are located at low galactic latitudes and present strong galactic cirrus in the optical images, the dust contamination being the most probable explanation for their inclusion in the PSZ2 catalogue.
- ID:
- ivo://CDS.VizieR/J/A+A/631/A148
- Title:
- PSZ2 cluster candidates. II.
- Short Name:
- J/A+A/631/A148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The second legacy catalog of Planck Sunyaev-Zeldovich (SZ) sources, hereafter PSZ2, provides the largest galaxy cluster sample selected by means of the SZ signature of the clusters in a full sky survey. In order to fully characterize this PSZ2 sample for cosmological studies, all the members should be validated and the physical properties of the clusters, including mass and redshift, should be derived. However, at the time of its publication, roughly 21% of the 1653 PSZ2 members had no known counterpart at other wavelengths. Here, we present the second and last year of observations of our optical follow-up program 128-MULTIPLE-16/15B (hereafter LP15), which has been developed with the aim of validating all the unidentified PSZ2 sources in the northern sky with declinations higher than -15{deg} that have no correspondence in the first Planck catalog PSZ1. The description of the program and the first year of observations have been presented previously. The LP15 program was awarded 44 observing nights that were spread over two years with the Isaac Newton Telescope (INT), the Telescopio Nazionale Galileo (TNG), and the Gran Telescopio Canarias (GTC), all at Roque de los Muchachos Observatory (La Palma). Following the same method as described previously, we performed deep optical imaging for more than 200 sources with the INT and spectroscopy for almost 100 sources with the TNG and GTC at the end of the LP15 program. We adopted robust confirmation criteria based on velocity dispersion and richness estimates for the final classification of the new galaxy clusters as the optical counterparts of the PSZ2 detections. Here, we present the observations of the second year of LP15, as well as the final results of the program. The full LP15 sample comprises 190 previously unidentified PSZ2 sources. Of these, 106 objects were studied before, while the remaining sample (except for 6 candidates) has been completed in the second year and is discussed here. In addition to the LP15 sample, we here study 42 additional PSZ2 objects that were originally validated as real clusters because they matched a WISE or PSZ1 counterpart, but they had no measured spectroscopic redshift. In total, we confirm the optical counterparts for 81 PSZ2 sources after the full LP15 program, 55 of them with new spectroscopic information. Forty of these 81 clusters are presented in this paper. After the LP15 observational program the purity of the PSZ2 catalog has increased from 76.7% originally to 86.2%. In addition, we study the possible reasons for false detection, and we report a clear correlation between the number of unconfirmed sources and galactic thermal dust emission.
- ID:
- ivo://CDS.VizieR/J/A+A/655/A115
- Title:
- PSZ1 galaxy clusters {sigma} and Mdyn
- Short Name:
- J/A+A/655/A115
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We present the velocity dispersion and dynamical mass estimates for 270 galaxy clusters included in the first Planck Sunyaev-Zeldovich (SZ) source catalogue, the PSZ1. Part of the results presented here were achieved during a two-year observational program, the ITP, developed at the Roque de los Muchachos Observatory (La Palma, Spain). In the ITP we carried out a systematic optical follow-up campaign of all the 212 unidentified PSZ1 sources in the northern sky that have a declination above -15{deg} and are without known counterparts at the time of the publication of the catalogue. We present for the first time the velocity dispersion and dynamical mass of 58 of these ITP PSZ1 clusters, plus 35 newly discovered clusters that are not associated with the PSZ1 catalogue. Using Sloan Digital Sky Survey archival data, we extend this sample, including 212 already confirmed PSZ1 clusters in the northern sky. Using a subset of 207 of these galaxy clusters, we constrained the M_SZ_-M_dyn_ scaling relation, finding a mass bias of (1-B)=0/83+/-0.07(stat)+/-0.02(sys). We show that this value is consistent with other results in the literature that were obtained with different methods (X-ray, dynamical masses, or weak-lensing mass proxies). This result cannot dissolve the tension between primordial cosmic microwave background anisotropies and cluster number counts in the {OMEGA}_M_-{sigma}8 plane.
- ID:
- ivo://CDS.VizieR/J/A+A/647/A106
- Title:
- PSZSPT, joint Planck and SPT-SZ cluster catalog
- Short Name:
- J/A+A/647/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first cluster catalogue extracted from combined space- (Planck) and ground-based (South Pole Telescope; SPT-SZ) millimeter data. We develop and apply a Matched Multi-Filter (MMF) capable of dealing with the different transfer functions and resolutions of the two datasets. We verified that it produces results consistent with publications from Planck and SPT collaborations when applied on the datasets individually. We also verified that Planck and SPT-SZ cluster fluxes are consistent with each other. When applied blindly to the combined dataset, the MMF generated a catalogue of 419 detections (S/N>5), of which 323 are already part of the SPT-SZ or PSZ2 catalogues; 54 are new SZ detections, identified in other catalogues or surveys; and 42 are new unidentified candidates. The MMF takes advantage of the complementarity of the two datasets, Planck being particularly useful for detecting clusters at low redshift (z<0.3) while SPT is efficient at finding higher redshift (z>0.3) sources. This work represents a proof of concept that blind cluster extraction can be performed on combined, inhomogeneous millimeter datasets acquired from space and ground. This result is of prime importance for planned ground-based cosmic microwave background (CMB) experiments (e.g., Simons Observatory, CMB-S4) and envisaged CMB space missions (e.g., PICO, Backlight) that will detect hundreds of thousands of clusters in the low mass regime (M500<10^14^M_{sun}_), for which the various sources of intra-cluster emission (gas, dust, synchrotron) will be of same order of magnitude and hence require broad ground+space frequency coverage with comparable spatial resolution for adequate separation.
- ID:
- ivo://CDS.VizieR/J/ApJ/896/70
- Title:
- Radial acceleration relation in CLASH galaxy clusters
- Short Name:
- J/ApJ/896/70
- Date:
- 03 Dec 2021 13:12:15
- Publisher:
- CDS
- Description:
- The radial acceleration relation (RAR) in galaxies describes a tight empirical scaling law between the total acceleration g_tot_(r)=GM_tot_(<r)/r^2^ observed in galaxies and that expected from their baryonic mass g_bar_(r)=GM_bar_(<r)/r^2^, with a characteristic acceleration scale of g_{dagger}_~1.2x10^-10^m/s^2^. Here, we examine if such a correlation exists in galaxy clusters using weak-lensing, strong-lensing, and X-ray data sets available for 20 high-mass clusters targeted by the Cluster Lensing And Supernova survey with Hubble (CLASH). By combining our CLASH data with stellar mass estimates for the brightest cluster galaxies (BCGs) and accounting for the stellar baryonic component in clusters, we determine, for the first time, an RAR on BCG-cluster scales. The resulting RAR is well described by a tight power-law relation, g_tot_{propto}g_bar_^0.51-0.05+0.04^, with lognormal intrinsic scatter of 14.7_-2.8_^+2.9^%. The slope is consistent with the low acceleration limit of the RAR in galaxies, g_tot_=(g_{dagger}_,g_bar_)^0.5^, whereas the intercept implies a much higher acceleration scale of g_{dagger}_=(2.02+/-0.11)x10^-9^m/s^2^, indicating that there is no universal RAR that holds on all scales from galaxies to clusters. We find that the observed RAR in CLASH clusters is consistent with predictions from a semianalytical model developed in the standard {Lambda}CDM framework. Our results also predict the presence of a baryonic Faber-Jackson relation ({sigma}_v^4^{propto}M_bar_) on cluster scales.
- ID:
- ivo://CDS.VizieR/J/MNRAS/391/1009
- Title:
- Radial kinematics in bright cluster galaxies
- Short Name:
- J/MNRAS/391/1009
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first of a series of papers devoted to the investigation of a large sample of brightest cluster galaxies (BCGs), their kinematic and stellar population properties, and the relationships between those and the properties of the cluster. We have obtained high signal-to-noise ratio, long-slit spectra of these galaxies with Gemini and William Herschel Telescope with the primary purpose of investigating their stellar population properties. This paper describes the selection methods and criteria used to compile a new sample of galaxies, concentrating on BCGs previously classified as containing a halo (cD galaxies), together with the observations and data reduction. Here, we present the full sample of galaxies, and the measurement and interpretation of the radial velocity and velocity dispersion profiles of 41 BCGs.
