- ID:
- ivo://CDS.VizieR/J/AJ/98/1148
- Title:
- VLA survey of 0016+16, Abell 665, and Abell 2218
- Short Name:
- J/AJ/98/1148
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the VLA to survey the fields of the three clusters of galaxies; 0016+16, Abell 665 (0826+66) and Abell 2218 (1635+66) at 1440 MHz, 4860 MHz, and 14940 MHz (for the brighter sources). The survey was aimed at finding radio sources which might contaminate the Sunyaev-Zel'dovich effect. We have detected 86 sources in these three clusters and examined Palomar sky survey prints for possible optical identifications.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/80/501
- Title:
- VLA survey of Abell clusters. II.
- Short Name:
- J/ApJS/80/501
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radio contour maps, models, and optical identifications for 130 radio galaxies in Abell clusters of galaxies.
- ID:
- ivo://CDS.VizieR/J/AJ/109/853
- Title:
- VLA survey of Abell clusters. IV.
- Short Name:
- J/AJ/109/853
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the fourth in a series of papers describing an in depth study of a large statistical sample of radio galaxies in Abell clusters. This sample forms the basis of a detailed optical and radio study of the host galaxy properties, environments, and evolutionary models for radio galaxies as a class of objects. In this paper, we examine the radio detection statistics as a function of cluster morphological type, galaxy richness, and spatial location within the cluster galaxy distribution. These relationships are also parametrized as a function of radio power. The spatial distributions of the radio sources as a function of distance from the cluster center indicate that radio galaxies are preferentially located at small radii from the center of the cluster potential. This is observed as a factor of 2-3 excess over that predicted by a King-model surface-density distribution. The excess is higher in the upper radio power bin. This result is easily explained, however, from the spatial distribution of the brightest galaxies and the relationship between radio and optical luminosity. The sample is divided into richness classes 0, 1, and 2, according to Abell's criterion, and in two radio power ranges. While simple counting shows that richer clusters have more radio galaxies in both radio power bins, when the detections are scaled to the number of galaxies surveyed in each cluster, no significant correlations are found. This result implies that the number of radio galaxies detected simply scales with the number of galaxies surveyed. The higher galaxy density (and presumably higher ICM gas density) in richer clusters does not appear to affect the rate of radio source formation. The clusters are divided into Rood-Sastry and Bautz-Morgan morphological types. While it would appear that the more regular clusters have higher radio detection rates, when the classes are normalized to the number of galaxies, the radio detection rates are found to be identical regardless of cluster morphology. In conclusion, it is the optical properties of the host galaxy which most influence both the radio detection rate and the radio source properties. The cluster properties, galaxy density, and spatial location of the galaxy do not significantly affect the observed radio statistics.
- ID:
- ivo://CDS.VizieR/J/AJ/98/64
- Title:
- VLA survey of Abell clusters of galaxies I.
- Short Name:
- J/AJ/98/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of a VLA survey at 20cm of a complete sample of nearby Abell clusters (D<=3). We have compiled an extensive catalog of cluster radio sources with S_20_>10mJy from a combination of our VLA observations and observations of similar resolution with the Westerbork Synthesis Radio Telescope (WSRT). Using these radio data and X-ray data from the Einstein observatory, we have analyzed the properties of these clusters. Unlike that previously suggested, no significant correlation is found between 20cm radio power and X-ray luminosity. There is weak evidence that richer clusters have a higher probability of radio emission. Based on Rood-Sastry morphological types of clusters, we do not find any strong evidence that regular-type clusters are statistically more likely to be radio loud than irregular-type clusters. However, Bautz-Morgan types I and II-III are found to have comparable radio-detection rates; but Bautz-Morgan Type III clusters are likely to have a lower radio-detection rate. A weak correlation between X-ray-cooling mass-accretion rates and radio powers was found for central, dominant galaxies in cooling-flow clusters. This might suggest that either cooling accretion directly fuels the central engine and/or cooling flows strongly interact with (e.g., confine) the radio plasma. In addition, radio sources associated with central dominant galaxies in cooling-flow clusters tend to be small in comparison with those in non-cooling-flow clusters. This might suggest that cooling flows tend to obstruct the propagation of radio jets from central, dominant galaxies.
- ID:
- ivo://CDS.VizieR/J/AJ/110/1959
- Title:
- VLA survey of Abell clusters. V.
- Short Name:
- J/AJ/110/1959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from a program of optical imaging of 265 radio galaxies in rich clusters. Using isophotal surface photometry, we investigate the optical properties such as the morphology, surface-brightness profiles, surface-brightness/size relationships, ellipticities, and the frequency of nonelliptical isophotes. The results are compared to a "normal" nonradio-selected sample of elliptical galaxies from the same clusters. The goal is to determine if the parent population of FR I radio galaxies can be distinguished optically from radio-quiet galaxies. The results of the analysis are that cluster ellipticals are a very homogeneous class of objects. The optical properties are consistent with a one-parameter family, where the optical luminosity is the fundamental parameter. In all tests considered, radio-loud FR I galaxies cannot be distinguished optically from radio-quiet galaxies selected from the same environment. The local density of nearby companions (<20kpc) and the frequency of morphological peculiarities or tidal interactions are not statistically different between the radio-loud and quiet samples. There is some suggestion from comparison to published samples of non-cluster radio galaxies, that the cluster environment is not condusive to long-lived tidal interactions, and that such events may be more important to galaxy evolution in poor groups and lower density environments. Such events appear to have little influence on the formation of FR I radio galaxies in rich clusters. The results are consistent with the idea that all elliptical galaxies may at some time (or many times) contain powerful (FR I) radio sources.
- ID:
- ivo://CDS.VizieR/J/AJ/113/1939
- Title:
- VLA Survey of Hercules cluster. I.
- Short Name:
- J/AJ/113/1939
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents results from a survey of lambda 21-cm emission from galaxies in the Hercules cluster, A2151 and A2147. Four VLA primary beam areas were covered, a total area of 0.9 square degrees, including some 120 spiral galaxies brighter than 17.5m. The velocity resolution is 44km/s, the angular resolution 25". The detection threshold at field center is 2.6x10^8 h^{-2}M_{sun}_ in H I mass or about 1.8x10^20cm^-2^ in column density. There are 61 galaxies detected in H I, of which about 25 had been previously detected at lambda 21-cm. About ten of the detections correspond to galaxies that are very faint in the optical, m_E_>=18 or M>=-17mag-5logh. Some of these low surface brightness galaxies have very extended H I disks, with r>=15kpc. The abundance of H I is a strong function of position in the cluster, with galaxies in the south and west showing hardly any gas, and galaxies in the north and east of A2151 frequently having massive, extended gas disks. The morphology of the remnants of gas in galaxies in the south and west suggests that the intracluster medium is responsible for their H I deficiency, but there are also several dramatic galaxy mergers in progress. (c) 1997 American Astronomical Society.
- ID:
- ivo://CDS.VizieR/VIII/50
- Title:
- VLA Survey of Rich Clusters of Galaxies
- Short Name:
- VIII/50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed 60 fields towards 57 Abell and one Zwicky cluster of galaxies using the Very Large Array (VLA) with scaled arrays at 1.5 and 4.9 GHz. The source catalogue contains radio and optical parameters for 994 sources up to a lower flux limit of 1.0 mJy at 1.5 GHz and comprises a complete sample above 2.5 mJy. The combined sky area within the half-power circle on the maps is 3.5x10^-3^ sr, and the cluster fields are distributed between +35 deg and -30 deg declination. The source catalogue list positions, angular size, spectral index and optical identification, magnitude and morphology, if available.
- ID:
- ivo://CDS.VizieR/J/ApJ/663/164
- Title:
- VLT and ACS observations in RDCS J1252.9-2927
- Short Name:
- J/ApJ/663/164
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from an extensive spectroscopic survey, carried out with VLT FORS, and from an extensive multiwavelength imaging data set from the HST Advanced Camera for Surveys and ground-based facilities, of the cluster of galaxies RDCS J1252.9-2927.
- ID:
- ivo://CDS.VizieR/J/ApJ/822/78
- Title:
- VLT/MUSE spectroscopic obs. of MACS J1149.5+2223
- Short Name:
- J/ApJ/822/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Multi Unit Spectroscopic Explorer (MUSE) observations in the core of the Hubble Frontier Fields (HFF) galaxy cluster MACSJ1149.5+2223, where the first magnified and spatially resolved multiple images of supernova (SN) "Refsdal" at redshift 1.489 were detected. Thanks to a Director's Discretionary Time program with the Very Large Telescope and the extraordinary efficiency of MUSE, we measure 117 secure redshifts with just 4.8hr of total integration time on a single 1arcmin^2^ target pointing. We spectroscopically confirm 68 galaxy cluster members, with redshift values ranging from 0.5272 to 0.5660, and 18 multiple images belonging to seven background, lensed sources distributed in redshifts between 1.240 and 3.703. Starting from the combination of our catalog with those obtained from extensive spectroscopic and photometric campaigns using the Hubble Space Telescope (HST), we select a sample of 300 (164 spectroscopic and 136 photometric) cluster members, within approximately 500kpc from the brightest cluster galaxy, and a set of 88 reliable multiple images associated with 10 different background source galaxies and 18 distinct knots in the spiral galaxy hosting SN "Refsdal". We exploit this valuable information to build six detailed strong-lensing models, the best of which reproduces the observed positions of the multiple images with an rms offset of only 0.26". We use these models to quantify the statistical and systematic errors on the predicted values of magnification and time delay of the next emerging image of SN "Refsdal". We find that its peak luminosity should occur between 2016 March and June and should be approximately 20% fainter than the dimmest (S4) of the previously detected images but above the detection limit of the planned HST/WFC3 follow-up. We present our two-dimensional reconstruction of the cluster mass density distribution and of the SN "Refsdal" host galaxy surface brightness distribution. We outline the road map toward even better strong-lensing models with a synergetic MUSE and HST effort.
- ID:
- ivo://CDS.VizieR/J/A+A/432/381
- Title:
- VLT spectroscopic survey of RX J0152.7-1357
- Short Name:
- J/A+A/432/381
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of an extensive spectroscopic survey of RX J0152.7-1357, one of the most massive distant clusters of galaxies known. Multi-object spectroscopy, carried out with FORS1 and FORS2 on the ESO Very Large Telescope (VLT), has allowed us to measure more than 200 redshifts in the cluster field and to confirm 102 galaxies as cluster members. The mean redshift of the cluster is z=0.837+/-0.001 and we estimate the velocity dispersion of the overall cluster galaxy distribution to be ~1600km/s.
