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Compact Steep-Spectrum Radio Sources and Ambient Medium Density
International Journal of Astrophysics and Space Science
Volume 3, Issue 1, February 2015, Pages: 1-6
Received: Jan. 13, 2015; Accepted: Feb. 6, 2015; Published: Feb. 16, 2015
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Ezeugo Jeremiah Chukwuemerie, Department of Physics and Industrial physics, NnamdiAzikiwe University, Awka, Anambra State, Nigeria
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Analytical and statistical methods,with some plausible assumptions, have been used in this work to show presence of dense medium around compact steep-spectrum sources in our sample. This is done by carrying out regression analyses using our estimated jet’s internal densities (n_j ) and some other source parameters for possible deductions. Results indicate that n_j-D and n_j-n_e data (where D and n_e are respectively, observed source linear size and ambient medium density) show strong correlations and yield power-law relations of the forms, n_j~D^(-3.54±0.02) and n_j~n_e^(1.68±0.08). A comparison with obtained theoretical relations suggestively indicates presence of dense gases around these sources. In addition, a simple linear regression analysis of ν_p-n_j data shows that jet’s particles may be responsible (in addition to the ambient gases) for the observed spectral turnover characteristic of compact steep spectrum sources.
Spectral Turnover, Steep-Spectrum, Astrophysical Jet, Ambient Density, Active Galaxies
To cite this article
Ezeugo Jeremiah Chukwuemerie, Compact Steep-Spectrum Radio Sources and Ambient Medium Density, International Journal of Astrophysics and Space Science. Vol. 3, No. 1, 2015, pp. 1-6. doi: 10.11648/j.ijass.20150301.11
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