Please use this identifier to cite or link to this item: http://hdl.handle.net/2289/4234
Title: On the interpretation of the observed angular-size-flux-density relation for extragalactic radio sources
Authors: Kapahi, V.K.
Subrahmanya, C.R.
Kulkarni, V.K.
Keywords: Cosmology
Extragalactic Radio Sources
Radiant Flux Density
Luminosity
Red Shift
Size Distribution
Issue Date: Mar-1987
Publisher: Indian Academy of Sciences, Bangalore
Citation: Journal of Astrophysics and Astronomy, 1987, Vol. 8, p33
Abstract: The interpretation of the observed relation between median angular sizes (thetam) of extragalactic radio sources and flux density at 408 MHz has been examined. The predicted thetam-S relations based on well-observed strong sources in parent samples selected at 178 and 1400 MHz, and existing models of the evolving radio luminosity function, can be made to fit the observed relation only by invoking cosmological evolution in linear sizes even for the q(0) = 0 universe. Predictions based on a parent sample at 2.7 GHz are shown to overestimate the contribution of steep-spectrum, compact (SSC) sources in low-frequency samples unless the downward curvature in the spectra of such sources is taken into account. When approximate corrections are made for this effect, predictions based on the 2.7 GHz parent sample cannot obviate the need for linear size evolution as claimed in the literature.
Description: Restricted Access.
URI: http://hdl.handle.net/2289/4234
ISSN: 0250-6335
0973-7758 (online)
Alternative Location: http://adsabs.harvard.edu/abs/1987JApA....8...33K
http://dx.doi.org/10.1007/BF02714250
Copyright: 1987 Indian Academy of Sciences, Bangalore, India
Appears in Collections:Research Papers (A&A)

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