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- ID:
- ivo://CDS.VizieR/J/AJ/121/148
- Title:
- Photometry of Dorado Group Dwarf Galaxies
- Short Name:
- J/AJ/121/148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present V and I CCD photometry of suspected low surface brightness dwarf galaxies detected in a survey covering ~2.4 deg^2^ around the central region of the Dorado group of galaxies. The low surface brightness galaxies were chosen based on their sizes and magnitudes at the limiting isophote of 26V{mu}. The selected galaxies have magnitudes brighter than V~20 (MV~-11 for an assumed distance to the group of 17.2 Mpc), with central surface brightnesses {mu}_0_>22.5 Vmag.arcsec^-2^, scale lengths h>2", and diameters >=14" at the limiting isophote. Using these criteria, we identified 69 dwarf galaxy candidates. Four of them are large very low surface brightness galaxies that were detected on a smoothed image, after masking high surface brightness objects. Monte Carlo simulations performed to estimate completeness, photometric uncertainties and to evaluate our ability to detect extended low surface brightness galaxies show that the completeness fraction is, on average, >80% for dwarf galaxies with -17<MV<-10.5 and 22.5<{mu}_0_<25.5 Vmag.arcsec^-2^, for the range of sizes considered by us (D>=14"). The V-I colors of the dwarf candidates vary from -0.3 to 2.3 with a peak on V-I=0.98, suggesting a range of different stellar populations in these galaxies. The projected surface density of the dwarf galaxies shows a concentration toward the group center similar in extent to that found around five X-ray groups and the elliptical galaxy NGC 1132 studied by Mulchaey & Zabludoff (1999ApJ...514..133M), suggesting that the dwarf galaxies in Dorado are probably physically associated with the overall potential well of the group.
- ID:
- ivo://CDS.VizieR/J/ApJS/184/271
- Title:
- Photometry of galaxies in 3 clusters
- Short Name:
- J/ApJS/184/271
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the data processing and analysis techniques we are using to determine the structural and photometric properties of galaxies in our Gemini/HST Galaxy Cluster Project sample. The goal of this study is to understand cluster galaxy evolution in terms of scaling relations and structural properties of cluster galaxies at redshifts 0.15<z<1.0. To derive parameters such as total magnitude, half-light radius, effective surface brightness, and Sersic n, we fit r^1/4^ law and Sersic function two-dimensional surface brightness profiles to each of the galaxies in our sample. Using simulated galaxies, we test how the assumed profile affects the derived parameters and how the uncertainties affect our Fundamental Plane results. A catalog of photometry and surface brightness profile parameters is presented for three of the clusters in our sample, RX J0142.0+2131, RX J0152.7-1357, and RX J1226.9+3332 at redshifts 0.28, 0.83, and 0.89, respectively.
- ID:
- ivo://CDS.VizieR/J/ApJS/169/225
- Title:
- Photometry of galaxies in the Coma cluster
- Short Name:
- J/ApJS/169/225
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a set of UBVRIzJHKs photometry for 745 J+H-band-selected objects in a 22.5'x29.2' region centered on the core of the Coma Cluster. This includes 516 galaxies and is at least 80% complete to H=16, with a spectroscopically complete sample of 111 cluster members (nearly all with morphological classification) for H<14.5. For each object we present total Kron (1980ApJS...43..305K) magnitudes and aperture photometry. As an example, we use these data to derive color-magnitude relations for Coma early-type galaxies, measure the intrinsic scatter of these relations and its dependence on galaxy mass, and address the issue of color gradients.
- ID:
- ivo://CDS.VizieR/J/ApJS/153/397
- Title:
- Photometry of nearby cluster galaxies
- Short Name:
- J/ApJS/153/397
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric observations are presented for 8747 galaxies in the fields of 28 clusters with redshifts in the range 0.05<z<0.11 and spanning a wide range in Abell richness class. The primary motivation for this study is to provide a nearby sample of clusters whose galaxy populations can be used to provide an anchor point for evolutionary studies of cluster galaxy populations.
- ID:
- ivo://CDS.VizieR/J/AJ/105/1271
- Title:
- Pisces-Perseus supercluster. VI
- Short Name:
- J/AJ/105/1271
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New results are presented of Arecibo observations in the 21 cm line of 765 galaxies with declinations between 15.5 deg and 21.5 deg, in the Pisces-Perseus supercluster zone. If considered independently on the neighboring parts of the sky, this region, to the South of the supercluster ridge, shows significantly less evidence of structure on large scales in excess of 30 Mpc, contrasting substantially with the characteristics of the declination zones immediately to the North.
- ID:
- ivo://CDS.VizieR/J/A+A/580/A95
- Title:
- Planck/AMI Sunyaev-Zel'dovich measurements
- Short Name:
- J/A+A/580/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations and analysis of a sample of 123 galaxy clusters from the 2013 Planck catalogue of Sunyaev-Zel'dovich sources with the Arcminute Microkelvin Imager (AMI), a ground-based radio interferometer. AMI provides an independent measurement with higher angular resolution, 3arcmin compared to the Planck beams of 5-10arcmin. The AMI observations thus provide validation of the cluster detections, improved positional estimates, and a consistency check on the fitted size ({theta}_s_) and flux (Y_tot_) parameters in the generalised Navarro, Frenk and White (GNFW) model. We detect 99 of the clusters. We use the AMI positional estimates to check the positional estimates and error-bars produced by the Planck algorithms PowellSnakes and MMF3. We find that Y_tot_ values as measured by AMI are biased downwards with respect to the Planck constraints, especially for high Planck-S/N clusters. We perform simulations to show that this can be explained by deviation from the universal pressure profile shape used to model the clusters. We show that AMI data can constrain the {alpha} and {beta} parameters describing the shape of the profile in the GNFW model for individual clusters provided careful attention is paid to the degeneracies between parameters, but one requires information on a wider range of angular scales than are present in AMI data alone to correctly constrain all parameters simultaneously.
- ID:
- ivo://CDS.VizieR/J/A+A/536/A8
- Title:
- Planck early results. VIII. ESZ sample.
- Short Name:
- J/A+A/536/A8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first all-sky sample of galaxy clusters detected blindly by the Planck satellite through the Sunyaev-Zeldovich (SZ) effect from its six highest frequencies. This early SZ (ESZ) sample is comprised of 189 candidates, which have a high signal-to-noise ratio ranging from 6 to 29. Its high reliability (purity above 95%) is further ensured by an extensive validation process based on Planck internal quality assessments and by external cross-identification and follow-up observations. Planck provides the first measured SZ signal for about 80% of the 169 previously-known ESZ clusters. Planck furthermore releases 30 new cluster candidates, amongst which 20 meet the ESZ signal-to-noise selection criterion. At the submission date, twelve of the 20 ESZ candidates were confirmed as new clusters, with eleven confirmed using XMM-Newton snapshot observations, most of them with disturbed morphologies and low luminosities. The ESZ clusters are mostly at moderate redshifts (86% with z below 0.3) and span more than a decade in mass, up to the rarest and most massive clusters with masses above 1x10^15^M_{sun}_.
- ID:
- ivo://CDS.VizieR/J/A+A/562/A106
- Title:
- Planck submillimetre sources in Virgo Cluster
- Short Name:
- J/A+A/562/A106
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We cross-correlate the Planck Catalogue of Compact Sources (PCCS) with the fully sampled 84deg^2^ Herschel Virgo Cluster Survey (HeViCS) fields. We search for and identify the 857 and 545GHz PCCS sources in the HeViCS fields by studying their FIR/submm and optical counterparts. We find 84 and 48 compact Planck sources in the HeViCS fields at 857 and 545GHz, respectively. Almost all sources correspond to individual bright Virgo Cluster galaxies. The vast majority of the Planck detected galaxies are late-type spirals, with the Sc class dominating the numbers, while early-type galaxies are virtually absent from the sample, especially at 545GHz. We compare the HeViCS SPIRE flux densities for the detected galaxies with the four different PCCS flux density estimators and find an excellent correlation with the aperture photometry flux densities, even at the highest flux density levels. We find only seven PCCS sources in the HeViCS fields without a nearby galaxy as obvious counterpart, and conclude that all of these are dominated by Galactic cirrus features or are spurious detections. No Planck sources in the HeViCS fields seem to be associated to high-redshift proto-clusters of dusty galaxies or strongly lensed submm sources. Finally, our study is the first empirical confirmation of the simulation-based estimated completeness of the PCCS, and provides a strong support of the internal PCCS validation procedure.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A4
- Title:
- PLCK G004.5-19.5 images at 150, 325 and 610MHz
- Short Name:
- J/A+A/607/A4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radio observations of the galaxy cluster PLCK G004.5-19.5 (z=0.52) using the Giant Metrewave Radio Telescope at 150MHz, 325MHz, and 610MHz. We find an unusual arrangement of diffuse radio emission in the center and periphery of the cluster, as well as several radio galaxies with head-tail emission. A patch of peripheral emission resembles a radio relic, and central emission resembles a radio halo. Reanalysis of archival XMM-Newton X-ray data shows that PLCK G004.5-19.5 is disturbed, which has a known correlation with the existence of radio relics and halos. Given that the number of known radio halos and radio relics at z>0.5 is very limited, PLCK G004.5-19.5 is an important addition to understanding merger-related particle acceleration at higher redshifts.
