Resumen

ONUCHUKWU, C. C.  y  UBACHUKWU, A. A.. Selection effects and structural symmetries in the orientation based unified scheme. Rev. mex. astron. astrofis [online]. 2019, vol.55, n.1, pp.105-116. ISSN 0185-1101.

Using the projected linear size, (D) as an orientation parameter, the arm-length ratio, (Q) and the lobe-luminosity ratio, (R) as asymmetry parameters, we test the FR-II galaxies (Gs) and radio-loud quasar (Qs) unification scheme. Using the median values of our binned sample, our results, generally indicate that the D of the radio sources are smaller at higher redshifts z and at larger Q values, with the D of Qs smaller than those of Gs across all Q, z and R bins. Also, the D of Gs appear smaller for lower values of Q, if R ≤ 1.0 but become larger at higher values of Q if R > 1.0. For Qs, the D decreases with increasing Q, R and z. These results imply that the beaming effect is more important in Qs than in Gs. The D − R regression analyses for different Q and z subsamples suggest the importance of factors other than beaming and orientation in the interpretation of the evolution of these radio sources.

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