International Astronomy and Astrophysics Research Journal

Phenomenology of Astrophysical Jets and Quasar/Galaxy Unification

O. L. Ubah *

Nnamdi Azikiwe University, Awka, Nigeria.

J. C. Ezeugo

Nnamdi Azikiwe University, Awka, Nigeria.

*Author to whom correspondence should be addressed.

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Abstract

Statistical and analytical methods have been used in this work to explain some physical phenomena that occur in extragalactic radio jets. Linear regression analyses were carried out among all the source observable parameters in our sample. The sample contains radio loud quasars and radio galaxies. Results of these analyses suggestively indicates that: (1) the physical phenomena which underscore the mechanisms of evolution of these extragalactic radio sources, and which manifest in their radio jet propagation have comparable origins; (2) the propagation of an extragalactic radio jet may depend on the following factors: (i) source energy density, (ii) jet solid angle, (iii) scale factor of the universe, (iv) angular size of the source, (v) density parameter, and (vi) ambient gas particle number density; (3) jet velocity scales as the square root of source energy density and inverse square root of source ambient medium density; (4) radio loud quasars and their galaxy counterparts are similar sources probably seen from different angles of observations. This supports Quasar/Galaxy Unification scheme. In this scheme, the two sub-classes of objects are expected to differ only in their aspect-dependent properties if orientation effects are the major factors that determine their different observed physical features.

Keywords: Black holes, luminosity, quasars, radio galaxies, redshift, jet velocity, radio jets, phenomenology, scale factor, unification scheme

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