scholarly journals Applications of statistical techniques to the angular size-Flux density relation for extragalactic radio sources

1977 ◽  
Vol 180 (4) ◽  
pp. 525-537 ◽  
Author(s):  
J. V. Narlikar ◽  
S. M. Chitre
Keyword(s):  
Flux Density ◽  
Angular Size ◽  
Statistical Techniques ◽  
Radio Sources ◽  
Extragalactic Radio Sources ◽  
Density Relation

On the interpretation of the observed angular-size-flux-density relation for extragalactic radio sources

1987 ◽  
Vol 8 (1) ◽  
pp. 33-50 ◽  
Author(s):  
V. K. Kapahi ◽  
V. K. Kulkarni ◽  
C. R. Subrahmanya
Keyword(s):  
Flux Density ◽  
Angular Size ◽  
Radio Sources ◽  
Extragalactic Radio Sources ◽  
Density Relation

scholarly journals The Angular Size Distribution of Radio Sources at Low Flux Densities

1982 ◽  
Vol 97 ◽  
pp. 393-400
Author(s):  
Ann Downes
Keyword(s):  
Size Distribution ◽  
Flux Density ◽  
Angular Size ◽  
Linear Size ◽  
Radio Sources ◽  
High Flux ◽  
Extragalactic Radio Sources ◽  
Size Evolution

Observations of complete samples of extragalactic radio sources at low and intermediate flux densities are described. Many types of source are found. The angular sizes form a smooth extrapolation from higher flux densities, and can be predicted from the known properties of samples at high flux density either with linear size evolution (for Ω = 1 or Ω = 0 Universes) or without linear size evolution (for Ω = 0). The question of whether such evolution is required therefore remains open.

scholarly journals The Flux Density-Angular Size Distribution for Extragalactic Radio Sources

1977 ◽  
Vol 74 ◽  
pp. 125-132 ◽  
Author(s):  
G. Swarup ◽  
C. R. Subrahmanya
Keyword(s):  
Size Distribution ◽  
Flux Density ◽  
Angular Size ◽  
Evolutionary Model ◽  
Radio Sources ◽  
Extragalactic Radio Sources ◽  
Size Evolution ◽  
Theoretical Predictions ◽  
Best Fit ◽  
Remarkable Agreement

The median values of angular sizes of weak extragalactic radio sources, the flux densities of which lie in the range of about 0. 3 to 5 Jy at 327 MHz, have been determined for a new sample of 119 sources observed during 1973-74, and agree well with the value of about 10 arc sec determined earlier by Swarup (1975). For 8 different flux density ranges, the angular size distribution for the All-sky, 3CR and Ooty radio sources have been compared with theoretical predictions based on the evolutionary model by Kapahi (1975) and show a remarkable agreement with his model except that the best fit is found for a linear size evolution proportional to (l+z)−1.

scholarly journals The “Number — Flux Density” Relation for Milliarcsecond Structures in Extragalactic Radio Sources

2001 ◽  
Vol 205 ◽  
pp. 146-147
Author(s):  
L.I. Gurvits
Keyword(s):  
Flux Density ◽  
Radio Sources ◽  
Extragalactic Radio Sources ◽  
Density Distributions ◽  
Density Relation

“Number - flux density” distributions for total and correlated flux densities at various interferometer spacings in 355 extragalactic radio sources are analysed. Qualitative conclusions on the population of milliarcsecond components in these sources are presented.

scholarly journals Cosmological Size Evolution of Extragalactic Radio Sources

1996 ◽  
Vol 175 ◽  
pp. 563-566
Author(s):  
Ashok K. Singal
Keyword(s):  
Radio Source ◽  
Size Distribution ◽  
Flux Density ◽  
Angular Size ◽  
Radio Sources ◽  
Source Population ◽  
Extragalactic Radio Source ◽  
Quarter Century ◽  
Extragalactic Radio Sources ◽  
Size Evolution

The study of cosmological evolution of the sizes of extragalactic radio sources started about a quarter century back. From the very first angular size-redshift (θ-z) plots (Miley 1968, 1971; Legg 1970) and angular size-flux density (θ-S) plots (Swarup 1975; Kapahi 1975) it became evident that some sort of cosmic epoch-dependent evolution in the size distribution for the population of extragalactic radio source needs to be proposed; the sources at earlier epochs appeared on the average to have smaller physical sizes. However, a suitable luminosity-linear size (P-l) correlation among the radio source population could also explain the observations, without invoking a size evolution with redshift. The only reliable way to disentangle these two separate effects is to investigate the size distribution in the luminosity-redshift plane, where one could examine not only the l-z relation for a given luminosity class, but could also check for a P-l correlation in a given redshift bin.

Flux-Density Relation of Extragalactic Radio Sources

1973 ◽  
Vol 186 ◽  
pp. 403 ◽  
Author(s):  
Vahe Petrosian ◽  
John Dickey
Keyword(s):  
Flux Density ◽  
Radio Sources ◽  
Extragalactic Radio Sources ◽  
Density Relation

scholarly journals Further high-resolution observations of faint radio sources and the angular size–flux density relation

1983 ◽  
Vol 204 (2) ◽  
pp. 289-315 ◽  
Author(s):  
J. Fielden ◽  
A. J. B. Downes ◽  
J. R. Allington-Smith ◽  
C. R. Benn ◽  
M. S. Longair ◽  
...  
Keyword(s):  
High Resolution ◽  
Flux Density ◽  
Angular Size ◽  
Radio Sources ◽  
Density Relation

The Flux Density-Angular Size Distribution for Extragalactic Radio Sources

1977 ◽  
pp. 125-132 ◽  
Author(s):  
G. Swarup ◽  
C. R. Subrahmanya
Keyword(s):  
Size Distribution ◽  
Flux Density ◽  
Angular Size ◽  
Radio Sources ◽  
Extragalactic Radio Sources

scholarly journals The Caltech-Jodrell Bank VLBI Surveys

1998 ◽  
Vol 164 ◽  
pp. 17-24
Author(s):  
T.J. Pearson ◽  
I.W.A. Browne ◽  
D.R. Henstock ◽  
A.G. Polatidis ◽  
A.C.S. Readhead ◽  
...  
Keyword(s):  
Flux Density ◽  
Angular Size ◽  
Optical Observations ◽  
Radio Sources ◽  
Limited Sample ◽  
Extragalactic Radio Sources ◽  
Superluminal Motion ◽  
Definition Of ◽  
5 Ghz

AbstractThe Caltech-Jodrell Bank VLBI surveys of bright extragalactic radio sources north of declination 35° were carried out between 1990 and 1995 using the Mark-II system, achieving images with a resolution of about 1 mas at 5 GHz. The CJl survey (together with the older “PR” survey) includes 200 objects with 5 GHz flux density greater than 0.7 Jy; the CJ2 survey includes 193 flat-spectrum sources with 5 GHz flux density greater than 0.35 Jy; and we have defined a complete flux-density limited sample, CJF, of 293 flat-spectrum sources stronger than 0.35 Jy. We summarize the definition of the samples and the VLBI, VLA, MERLIN, and optical observations, and present some highlights of the astrophysical results. These include: (1) superluminal motion and cosmology; (2) morphology and evolution of the “compact symmetric objects” (CSOs); (3) two-sided motion in some CSOs; (4) the angular-size-redshift diagram; (5) misalignment of parsec-scale and kiloparsec-scale jets.

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