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- ID:
- ivo://CDS.VizieR/J/AJ/122/1125
- Title:
- BVRI photometry in 3 high-z clusters
- Short Name:
- J/AJ/122/1125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New photometric and spectroscopic observations of galaxies in the directions of three distant clusters are presented as part of our ongoing high-redshift cluster survey. The clusters are Cl 1324+3011 at z=0.76, Cl 1604+4304 at z=0.90, and Cl 1604+4321 at z=0.92. We have spectroscopically confirmed cluster membership for 2040 galaxies in each system and have also obtained spectra for over 280 field galaxies spanning the range 0<z<2.5.
- ID:
- ivo://CDS.VizieR/J/AJ/122/38
- Title:
- BVRI photometry of Abell 2443
- Short Name:
- J/AJ/122/38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present broadband photometry and provide a quantitative analysis of the structure of galaxies in the inner region of the Abell Cluster 2443 (z~0.1). The galaxy parameters have been derived by fitting a two-component model (Sersic r^1/n^ bulge and exponential disk) to a magnitude-limited sample. Using a new method of analysis that takes into account the effects of seeing on the structural parameters and considers ellipticity as an active parameter, we avoid systematic errors arising from assumptions of circular symmetry. Of the sample galaxies, 76% were classified with these models, while the rest were morphologically peculiar. For the spiral galaxies, the relation between n and B/D is consistent with the trend observed in nearby field galaxy samples. The Sersic index n (which can be considered as a concentration index) of the elliptical galaxies is correlated with the local surface density of the cluster. Monte Carlo simulations were used to check the reliability of the method and determine the magnitude selection criteria. Observations were obtained on 1998 August 19 at the 2.5 m Nordic Optical Telescope (NOT) at the Observatorio del Roque de los Muchachos on La Palma. The prime-focus CCD camera was used with pixel scale of 0.11"/pix, and the seeing ranged from FWHM 0.88" to 1".
- ID:
- ivo://CDS.VizieR/J/ApJ/664/761
- Title:
- BVRI photometry of AGNs in clusters
- Short Name:
- J/ApJ/664/761
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the distribution of AGNs in clusters of galaxies with a uniformly selected, spectroscopically complete sample of 35 AGNs in eight clusters of galaxies at z=0.06-->0.31. We find that the 12 AGNs with LX>10^42^ergs/s in cluster members more luminous than a rest-frame M_R_<-20mag are more centrally concentrated than typical cluster galaxies of this luminosity, although these AGNs have comparable velocity and substructure distributions to other cluster members.
- ID:
- ivo://CDS.VizieR/J/A+A/382/60
- Title:
- BVR photometry in Abell 1689
- Short Name:
- J/A+A/382/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At a redshift of 0.18, Abell 1689 is so far the most distant cluster of galaxies for which substantial mid-infrared (MIR) data have been published. Its mapping with the ISOCAM camera onboard the ISO satellite allowed the detection of 30 cluster members at 6.75{mu}m (LW2 filter) and 16 cluster members at 15{mu}m (LW3 filter) within a clustercentric radius of 0.5Mpc (Fadda et al., 2000A&A...361..827F, Paper I). We present here the follow-up optical photometric and spectroscopic observations which were used to study the individual properties of the galaxy members of A1689. We confirm the high fraction of blue galaxies initially reported in this rich cluster by Butcher & Oemler (1984ApJ...285..426B), that was challenged by some subsequent studies. We discuss the spectral and morphological properties of all cluster members in our spectroscopic sample, and of the MIR-detected galaxies in particular.
- ID:
- ivo://CDS.VizieR/J/A+AS/128/67
- Title:
- BVR photometry of Abell 85
- Short Name:
- J/A+AS/128/67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two catalogues of galaxies in the direction of the rich cluster ABCG 85. The first one includes 4232 galaxies located in a region +/-1{deg} from the cluster centre. It has been obtained from a list of more than 25000 galaxy candidates detected by scanning a Schmidt photographic plate taken in the B_J_ band. Positions are very accurate in this catalogue but magnitudes are not. This led us to perform CCD imaging observations in the V and R bands to calibrate these photographic magnitudes. A second catalogue (805 galaxies) gives a list of galaxies with CCD magnitudes in the V and R bands for a much smaller region in the centre of the cluster. These two catalogues will be combined with a redshift catalogue of 509 galaxies by Durret et al. (1997, subm.) to investigate the cluster properties at optical wavelengths Durret et al. (1997, subm.), as a complement to our previous X-ray studies (Pislar et al., 1997A&A...322...53P; Lima-Neto et al., 1997A&A...327...81L).
- ID:
- ivo://CDS.VizieR/J/A+A/422/407
- Title:
- BVR photometry of MS0302+17
- Short Name:
- J/A+A/422/407
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the supercluster MS0302+17 (ClG 0302+17, z~0.42) using weak lensing analysis and deep wide field BVR photometry with the CFH12K camera. Using (B-V) vs (V-R) evolution tracks we identify early-type members of the supercluster, and foreground ellipticals. We derive a R band catalogue of background galaxies for weak lensing analysis. We compute the correlation functions of light and mass and their cross-correlation and test if light traces mass on supercluster, cluster and galaxy scales. We show that the data are consistent with this assertion. The {zeta}-statistic applied in regions close to cluster centers and global correlation analyses over the whole field converge toward the simple relation M/L=300+/-30M_{sun}_/L_{sun}_ in the B band. This independently confirms the earlier results obtained by Kaiser (1998ApJ...498...26K). If we model dark matter halos around each early-type galaxy by a truncated isothermal sphere, we find that a linear relation M{prop.to}L still holds. In this case, the average halo truncation radius is s_*_<~200(h_70_)^-1^kpc close to clusters cores whereas it reaches a lower limit of ~300(h_70_)^-1^kpc at the periphery. This change of s_*_ as a function of radial distance may be interpreted as a result of tidal stripping of early type galaxies. Nevertheless the lack of information on the spatial distribution of late-type galaxies affects such conclusions concerning variations of s_*_. Though all the data at hand are clearly consistent with the assumption that mass is faithfully traced by light from early-type galaxies, we are not able to describe in detail the contribution of late type galaxies. We however found it to be small. Forthcoming wide surveys in UV, visible, and near infrared wavelengths will provide large enough samples to extend this analysis to late-type galaxies using photometric redshifts.
138. Calibration list
- ID:
- ivo://CDS.VizieR/J/A+A/633/A42
- Title:
- Calibration list
- Short Name:
- J/A+A/633/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We demonstrate a novel technique for calibrating the energy scale of the EPIC-pn detector on XMM-Newton, which allows us to measure bulk flows in the intracluster medium (ICM) of the Perseus and Coma galaxy clusters. The procedure uses the fluorescent instrumental background lines present in all observations, in particular, Cu-Kalpha. By studying their spatial and temporal variations, in addition to incorporating calibration observations, we refined the absolute energy scale of the detector to better than 150km/s at the Fe-K line, a large improvement over the nominal calibration accuracy of 550km/s. With our calibration, we mapped the bulk motions over much of the central 1200 and 800kpc of Perseus and Coma, respectively, in spatial regions down to 65 and 140kpc size. We cross-checked our procedure by comparing our measurements with those found in Perseus by Hitomi for an overlapping 65 kpc square region, finding consistent results. For Perseus, there is a relative line-of-sight velocity increase of 480+/-210km/s (1sigma) at a radius of 250kpc east of the nucleus. This region is associated with a cold front, providing direct evidence of the ICM sloshing in the cluster potential well. Assuming the intrinsic distribution of bulk motions is Gaussian, its width is 214+/-85km/s, excluding systematic uncertainties. Removing the sloshing region, this is reduced to 20-150km/s, which is similar in magnitude to the Hitomi line width measurements in undisturbed regions. In Coma, the line-of-sight velocity of the ICM varies between the velocities of the two central galaxies. Maps of the gas velocity and metallicity provide clues about the merger history of the Coma, with material to the north and east of the cluster core having a velocity similar to NGC 4874, while that to the south and west has velocities close to NGC 4889. Our results highlight the difference between a merging system, such as Coma, where we observe a ~1000 km/s range in velocity, and a relatively relaxed system, such as Perseus, with much weaker bulk motions.
- ID:
- ivo://CDS.VizieR/J/ApJ/765/94
- Title:
- Calibration of the mid-IR Tully-Fisher relation
- Short Name:
- J/ApJ/765/94
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Distance measures on a coherent scale around the sky are required to address the outstanding cosmological problems of the Hubble constant and of departures from the mean cosmic flow. The correlation between galaxy luminosities and rotation rates can be used to determine the distances to many thousands of galaxies in a wide range of environments potentially out to 200Mpc. Mid-infrared (3.6{mu}m) photometry with the Spitzer Space Telescope is particularly valuable as a source of luminosities because it provides products of uniform quality across the sky. From a perch above the atmosphere, essentially the total magnitude of targets can be registered in exposures of a few minutes. Extinction is minimal and the flux is dominated by the light from old stars, which is expected to correlate with the mass of the targets. In spite of the superior photometry, the correlation between mid-infrared luminosities and rotation rates extracted from neutral hydrogen profiles is slightly degraded from the correlation found with I-band luminosities. A color correction recovers a correlation that provides comparable accuracy to that available at the I band (~20% 1{sigma} in an individual distance) while retaining the advantages identified above. Without color correction, the relation between linewidth and [3.6] magnitudes is M^b,i,k,a^_[3.6]_=-20.34-9.74(logW^i^_mx_-2.5). This description is found with a sample of 213 galaxies in 13 clusters that define the slope and 26 galaxies with Cepheid or tip of the red giant branch distances that define the zero point. A color-corrected parameter M_c[3.6]_ is constructed that has reduced scatter: M_c[3.6]_=-20.34-9.13(logW_mx_^i^-2.5). Consideration of the seven calibration clusters beyond 50Mpc, outside the domain of obvious peculiar velocities, provides a preliminary Hubble constant estimate of H_0_=74+/-4km/s.M/pc.
- ID:
- ivo://CDS.VizieR/J/ApJ/317/102
- Title:
- Cancer cluster 1.4GHz continuum sources
- Short Name:
- J/ApJ/317/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on 1.4GHZ continuum observations for 11 VLA fields, using the D-configuration, which contain the A group of the Cancer Cluster. Sixteen Zwicky spiral galaxies in the Cancer Cluster were detected, but no ellipticals. We corroborate the finding that spiral galaxies with close companions tend to have enhanced radio emission. Over 200 continuum sources beyond the Cancer Cluster are tabulated. The spectral index (relative to 610MHz) is given for many of the sources, including some of the Zwicky galaxies. There is a suggestion for a nonuniform number surface-density distribution of the sources, not correlated with the Cancer Cluster. Possible predictions of such nonuniformities, from assumptions on " super-superclusters," are discussed.
