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1995AJ....109..853Ledlow+
J/AJ/109/853 VLA survey of Abell clusters. IV. (Ledlow+ 1995)
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A 20 cm VLA survey of Abell clusters of galaxies.
IV. The radio sample and cluster properties
Ledlow M.J., Owen F.N.
Astron. J. 109, 853 (1995)
=1995AJ....109..853L
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ADC_Keywords: Clusters, galaxy ; Radio sources
Abstract:
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.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1a 137 511 Cluster radio survey (z<=0.09)
table1b 97 231 Cluster radio survey (0.09)
6- 7 A2 --- n_Abell *Abell number note
10- 15 F6.4 --- z []? Cluster redshift
16- 30 A15 --- r_z *Redshift reference code
31 A1 --- n_IAU *IAU name note
33- 42 A10 --- IAU (B1950) IAU name
44- 45 I2 h RAh []? Right ascension (B1950)
47- 48 I2 min RAm []? Right ascension (B1950)
50- 54 F5.2 s RAs []? Right ascension (B1950)
56 A1 --- DE- Declination sign (B1950)
57- 58 I2 deg DEd []? Declination (B1950)
60- 61 I2 arcmin DEm []? Declination (B1950)
63- 67 F5.2 arcsec DEs []? Declination (B1950)
70- 75 F6.1 mJy Flux []? Measured flux density at 1400MHz
77- 80 F4.2 --- Ac *[]? Distance from cluster center
82- 87 F6.3 mag 2E(B-V) []? Extinction at R band for the cluster
89- 93 F5.2 mag m10c *[]? Corrected m10
95-102 F8.4 --- z/zest []? Ratio log(z/z_est) based on m10c
104-106 A3 --- n_Status *Status note explaining rejection
108-129 A22 --- Status Status of source in statistical sample
130-137 A8 --- Other Other name
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Note on n_Abell, n_IAU, n_Status:
1 ID's on finder chart in O93 have labeled source A as D and source B as A.
2 ID's on finder chart in O92 have sources A and B switched.
3 ID's on finder chart in O93 have labeled source A as B and source B as C.
4 ID in O93 is labeled D on finder chart.
5 Only A is listed in O92, and is a background source.
6 ID's on finder in O92 have labeled sources A as C, B as A, and C as B.
7 Rejected because abs(log(z/z_est))>0.24.
8 Rejected because source is greater than 0.3 A_c from cluster center.
9 Rejected because galactic absorption is greater than 0.1 magnitudes.
10 Cluster was rejected because redshift is too low to have surveyed
0.5 A_c field.
11 Measured velocity was too different from mean cluster velocity
Note on r_z : Number in parentheses following reference code is the number
of galaxies used to compute the redshift. Reference codes are:
(ACO) Abell G.O. et al., 1989, ApJS, 70, 1
(H) Huchra J.P. 1989, private communication
(L) Lebedev V.S. and Lebedeva I.A. (1986ATsir1469....4L)
(OH) Oegerle W. and Hill J. M. (1992AJ....104.2078O)
(O92) Owen F.N. et al. (1992ApJS...80..501O)
(O93) Owen F.N. et al. (1993ApJS...87..135O)
(P) Postman M. et al.
(SGH) Schneider D.P. et al. (1983ApJ...264..337S)
(S) Struble M.F. and Rood H.J.
In on case, A2149, this column contains a second redshift
Note on Ac: The distance of the galaxy from the cluster center positions of
Abell [1958ApJS....3..211A] expressed in units of a fraction of an
Abell radius.
Note on m10c: The magnitude of the tenth brightest cluster galaxy corrected for
the Scott effect and K-dimming
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Byte-by-byte Description of file: table1b
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Bytes Format Units Label Explanations
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1- 4 A4 --- Abell Abell cluster number
6 A1 --- n_Abell *Abell number note
8- 19 A12 --- Redshift *Cluster redshift and reference code
21- 30 A10 --- IAU (B1950) IAU name
32- 33 I2 h RAh []? Right ascension (B1950)
35- 36 I2 min RAm []? Right ascension (B1950)
38- 42 F5.2 s RAs []? Right ascension (B1950)
44 A1 --- DE- Declination sign (B1950)
45- 46 I2 deg DEd []? Declination sign (B1950)
48- 49 I2 arcmin DEm []? Declination sign (B1950)
51- 54 F4.1 arcsec DEs []? Declination sign (B1950)
56- 60 I5 mJy Flux []? Measured flux density at 1400MHz
62- 66 F5.2 --- Ac *[]? Distance from cluster center
68- 72 F5.2 mag 2E(B-V) []? Extinction at R band for the cluster
74- 76 A3 --- n_Status *Status note explaining rejection
78- 97 A20 --- Status Status of Source in statistical sample
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Note on n_Abell, n_Status:
1 Cluster has High R-Extinction, but kept because source is FR2
2 Cluster found to have z<0.09. Left in sample, but not included
analysis
3 Radio flux slightly below 200 mJy cutoff, but left in sample
4 ID's on finder chart in O92 have sources A as B and B listed as C
5 Rejected because source is >0.5A_c from cluster center
6 Rejected because galactic absorption is >0.1 magnitudes
Note on Redshift:
Number in parentheses following reference code is the number of
galaxies used to compute the redshift. Reference codes are:
(H) Huchra, J.P. 1989, private communication
(L) Lebedev V.S. and Lebedeva I.A. (1986ATsir1469....4L)
(O92) Owen F.N. et al. (1992ApJS...80..501O)
(OLK) Owen F.N. et al. (1995AJ....109...14O)
(OWT) Owen F.N. et al. (1988AJ.....95....1O)
(P) Postman M.et al.
(S) Struble M.F. and Rood H.J.
Note on Ac: The distance of the galaxy from the cluster center positions of
Abell [1958, ApJS, 3, 211] expressed in units of a fraction of an
Abell radius.
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For correspondence or questions, contact :
Dr. Michael Ledlow
E-mail:
Phone : (505)646-3000
Address : New Mexico State University
Department of Astronomy
Box 30001/Dept. 4500
Las Cruces, NM 88003-0001
Origin: AAS CD-ROM series, Volume 4, 1995 Lee Brotzman [ADS] 02-May-1995
Modifications made at CDS:
In table1a the formats of '2E(B-V)' and 'z/zest' were changed to accommodate
3 and 4 decimals; column 'Flux' was also changed from I7 to F6.1
References:
Zhao et al., Paper I, 1989AJ.....98...64Z
Owen et al., Paper II, 1992ApJS...80..501O
Owen et al., Paper III, 1993ApJS...87..135O
Ledlow & owen, Paper IV, 1995AJ....110.1959
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(End) [CDS] 12-Jul-1995