On the Dependence of Spectral Turnover on Linear Size of Compact Steep Spectrum Radio Sources
International Journal of Astrophysics and Space Science
Volume 3, Issue 2, April 2015, Pages: 20-24
Received: Mar. 30, 2015; Accepted: Apr. 15, 2015; Published: Apr. 30, 2015
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Author
Ezeugo Jeremiah Chukwuemerie, Department of Physics and Industrial Physics, Nnamdi Azikiwe University, Awka, Nigeria
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Abstract
Frequency peak/linear size (ν_p-D) relation gives the strongest correlation among all the currently observable physical properties of Compact Steep Spectrum Sources (CSSs). This strong correlation suggests that the spectral turnover constitutes a characteristic signature of dense gases around the CSS sources which may be used to constrain physical mechanisms that govern the dynamical evolution of CSS sources. We have therefore, carried out statistical analyses to ascertain whether the observed ν_p-D correlation is real or an artifact arising from a possible spectral turnover/radio luminosity (ν_p-P) and/or linear size/radio luminosity (D-P) correlations. Our results show only a marginally significant ν_p-P correlation (correlation coefficient, r≈0.3) and apparently little or no D-P correlation. This suggests that the mechanism for the spectral turnover lies mainly in the source size according to the relation, ν_p~D^(-0.7), with correlation coefficient, r≈-0.9.
Keywords
Galaxies, Quasars, Radio, Luminosity, Redshift
To cite this article
Ezeugo Jeremiah Chukwuemerie, On the Dependence of Spectral Turnover on Linear Size of Compact Steep Spectrum Radio Sources, International Journal of Astrophysics and Space Science. Vol. 3, No. 2, 2015, pp. 20-24. doi: 10.11648/j.ijass.20150302.12
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