RELATIVISTIC BEAMING AND RADIO SOURCE ORIENTATION EFFECTS IN COMPACT STEEP-SPECTRUM RADIO SOURCES AND QUASAR-GALAXY UNIFICATION

Abstract

Analytical and statistical methods with some plausible assumptions have been used in this work to investigate
relativistic beaming and orientation effects in compact steep spectrum sources (CSSs); and its implications to
quasar/galaxy unification paradigm. Results suggestively indicate that jet axes of CSS quasars lie closer to our
line of sight than those of CSS galaxies which lie farther away. In addition, the flows from the cores of CSS
quasars are highly relativistic with optimum Lorentz factor, 𛾠ð‘œð‘𑡠≈ 2.1 − 3.3; while CSS galaxies are not
beamed. These results are consistent with the orientation-dependent relativistic beaming and radio source
unification paradigm, in which the flows from the cores of quasars are expected to be highly relativistic; and in
which Doppler effects generate anisotropic radiation patterns at close angles to our line of sight. Furthermore,
since our estimated results are comparable with those obtained for the more extended core-dominated radio
sources in the literature; therefore,CSSs suggestively are scaled-down versions of the conventional
extragalactic radio sources.