Photometric Observations of Southern Abell Cluster Redshifts Survey Clusters: Structure of Galaxies in the Inner Region of Clusters of Galaxies

2006 ◽  
Vol 131 (4) ◽  
pp. 1989-1995 ◽  
Author(s):  
Valeria Coenda ◽  
Hernan Muriel ◽  
Carlos José Donzelli ◽  
Hernan Quintana ◽  
Leopoldo Infante ◽  
...  
Keyword(s):  
Clusters Of Galaxies ◽  
Photometric Observations ◽  
Abell Cluster ◽  
Inner Region

scholarly journals Catalogue of Clusters that are Members of Superclusters

1983 ◽  
Vol 104 ◽  
pp. 185-186
Author(s):  
M. Kalinkov ◽  
K. Stavrev ◽  
I. Kuneva
Keyword(s):  
Standard Deviation ◽  
Correlation Coefficient ◽  
The Other ◽  
Clusters Of Galaxies ◽  
Number Of Clusters ◽  
Abell Clusters ◽  
The Mean ◽  
Abell Cluster ◽  
Image Position

An attempt is made to establish the membership of Abell clusters in superclusters of galaxies. The relation is used to calibrate the distances to the clusters of galaxies with two redshift estimates. One is m10, the magnitude of the ten-ranked galaxy, and the other is the “mean population,” P, defined by: where p = 40, 65, 105 … galaxies for richness groups 0, 1, 2 …, and r is the apparent radius in degrees given by: The first iteration for redshift, z1, is obtained from m10 alone: The standard deviation for Eq. (1) is 0.105, the number of clusters with known velocities is 342 and the correlation coefficient between observed and fitted values is 0.921. With zi from Eq. (1), we define Cartesian galactic coordinates Xi = Rih−1 cosBi cosLi, Yi = Rih−1 cosBi sinLi, Zi = Rih−1 sinBi for each Abell cluster, i = 1, …, 2712, where Ri is the distance to the cluster (Mpc), and Ho = 100 h km s−1 Mpc−1.

Radio Sources in Clusters of Galaxies

1977 ◽  
Vol 4 (1) ◽  
pp. 311-319
Author(s):  
Ian McHardy
Keyword(s):  
High Resolution ◽  
Radio Sources ◽  
Clusters Of Galaxies ◽  
Cluster Centre ◽  
Cluster Of Galaxies ◽  
Abell Cluster ◽  
Statistical Sample

Sixty-five radio sources in the 4C catalogue lie within 0.3 of the radius, Rc, defined by Abell (1958), of the centre of an Abell cluster of galaxies. Statistically few of these are expected to be chance coincidences and hence they provide a well defined statistical sample of sources in rich clusters of galaxies. Over the last 6 years sources from this sample having declinations greater than 10° have been observed with high resolution using the Cambridge One-Mile telescope by Slingo (1974(a) and (b)), Riley (1975) and by myself (1977, in preparation). The number of sources observed and the number expected by chance at different distances from the cluster centre are shown in Table I; the radio positions used are from the 4C catalogue.

A VLA Survey of Rich Clusters of Galaxies III. The Weaker Sources: Maps and Identifications

1996 ◽  
Vol 49 (5) ◽  
pp. 977 ◽  
Author(s):  
OB Slee ◽  
AL Roy ◽  
H Andernach
Keyword(s):  
Source Parameters ◽  
Angular Size ◽  
Optical Parameters ◽  
Clusters Of Galaxies ◽  
Very Large Array ◽  
Contour Maps ◽  
Optical Images ◽  
Extended Sources ◽  
Abell Cluster ◽  
Right Ascension

We present radio and optical parameters for 737 weak sources in 60 Abell cluster fields observed with the Very Large Array (VLA) using scaled arrays at 1.5 and 4.9 GHz. The measurements extend to a lower 1.5 GHz limit of 1.0 mJy and comprise a complete sample with 1.5 GHz flux density 2.5 ≤ S1.5 −3 sr, and the cluster fields are distributed over 24 h of right ascension and between declinations +35° and −30°. Contour maps of the extended sources at 1.5 GHz are presented and source parameters such as position, angular size and spectral index are tabulated. We also derive the emitted power and linear size for those sources with published redshifts. We try to identify the radio sources with optical images on the Palomar and SERC survey plates and give their accurate optical positions, morphologies and apparent magnitudes.

Beyond the Schwarzschild Metric

2018 ◽  
Author(s):  
David M. Wittman
Keyword(s):  
Black Holes ◽  
General Relativity ◽  
Gravitational Waves ◽  
Test Particle ◽  
Direct Detection ◽  
Relativistic Effects ◽  
Big Bang ◽  
Clusters Of Galaxies ◽  
General Relativistic ◽  
The Universe

General relativity explains much more than the spacetime around static spherical masses.We briefly assess general relativity in the larger context of physical theories, then explore various general relativistic effects that have no Newtonian analog. First, source massmotion gives rise to gravitomagnetic effects on test particles.These effects also depend on the velocity of the test particle, which has substantial implications for orbits around black holes to be further explored in Chapter 20. Second, any changes in the sourcemass ripple outward as gravitational waves, and we tell the century‐long story from the prediction of gravitational waves to their first direct detection in 2015. Third, the deflection of light by galaxies and clusters of galaxies allows us to map the amount and distribution of mass in the universe in astonishing detail. Finally, general relativity enables modeling the universe as a whole, and we explore the resulting Big Bang cosmology.

Magnetic Field Evolution in Merging Clusters of Galaxies

1999 ◽  
Vol 518 (2) ◽  
pp. 594-602 ◽  
Author(s):  
Kurt Roettiger ◽  
James M. Stone ◽  
Jack O. Burns
Keyword(s):  
Magnetic Field ◽  
Clusters Of Galaxies ◽  
Field Evolution

The Globular Cluster System in the Inner Region of M87

1999 ◽  
Vol 513 (2) ◽  
pp. 733-751 ◽  
Author(s):  
Arunav Kundu ◽  
Bradley C. Whitmore ◽  
William B. Sparks ◽  
F. Duccio Macchetto ◽  
Stephen E. Zepf ◽  
...  
Keyword(s):  
Globular Cluster ◽  
Cluster System ◽  
Globular Cluster System ◽  
Inner Region

scholarly journals Large Bent Jets in the Inner Region of CSS

1996 ◽  
Vol 175 ◽  
pp. 71-72
Author(s):  
F. Mantovani ◽  
W. Junor ◽  
M. Bondi ◽  
L. Padrielli ◽  
W. Cotton ◽  
...  
Keyword(s):  
Velocity Structure ◽  
Radio Sources ◽  
Ambient Media ◽  
The Core ◽  
Gaseous Environment ◽  
Radio Jets ◽  
Large Size ◽  
Superluminal Motion ◽  
Inner Region ◽  
Quasars And Radio Galaxies

Recently we focussed our attention on a sample of Compact Steep-spectrum Sources (CSSs) selected because of the large bent radio jets seen in the inner region of emission. The largest distortions are often seen in sources dominated by jets, and there are suggestions that this might to some extent be due to projection effects. However, superluminal motion is rare in CSSs. The only case we know of so far is 3C147 (Alef at al. 1990) with a mildly superluminal speed of ≃ 1.3v/c. Moreover, the core fractional luminosity in CSSs is ≃ 3% and ≤ 0.4% for quasars and radio galaxies respectively. Similar values are found for large size radio sources i.e. both boosting and orientations in the sky are similar for the two classes of objects. An alternative possibility is that these bent-jet sources might also be brightened by interactions with the ambient media. There are clear indications that intrinsic distortions due to interactions with a dense inhomogeneous gaseous environment play an important role. Observational support comes from the large RMs found in CSSs (Taylor et al. 1992; Mantovani et al. 1994; Junor et al. these proc.) and often associated with strong depolarization (Garrington & Akujor, t.p.). The CSSs also have very luminous Narrow Line Regions emission, with exceptional velocity structure (Gelderman, t.p.).

Sign in / Sign up

Export Citation Format

Share Document