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\subsection{Black holes and Active Galactic Nuclei}  It is widely accepted that there is a supermassive black hole (SMBH ) (with a mass ranging from $10^5$ – $10^{10}$ solar masses) at the center of most galaxies , though the although  there is some uncertainty about how these black holes are formed. Black holes are regions of space-time exhibiting strong gravitational pull. According to \citet{Loeb_2010} a black hole is the end product from the complete gravitational collapse of a material object, such as a massive star. The black hole is responsible for the mass concentration at the center of each galaxy. Black holes found at the center of galaxies are referred to as Super Massive Black Holes (SMBH). SMBH grow by merging with other black holes or by accretion of matter which is the process of attracting mater via a gravitational force leading to a growth of the attracting agent. Radio galaxies are galaxies dominated by radio emissions from jets stemming from SMBHs. AGN are the small, dense and luminous components of the centers of galaxies as represented in Figure 3 and ,and  Figure 4. The majority of their energy is thought to be derived from gravitational potential energy and SMBH spin as opposed to nuclear sources within stars. It was in the late 1940s when the connection between cosmic radio waves and synchrotron emission was established. In AGN, Bremsstrahlung, Synchrotron and Compton emission processes are most common. Synchrotron radiation accounts for much of the radio emissions in AGN. The jets of an AGN produce synchrotron radiation due to near-relativistic electrons spiraling around magnetic field lines.  This process produces polarized radiation in the direction of propagation of the emitting electron. The AGN's  torus emits unpolarized thermal radiation - refer to Figure 3. It has been theorized that the ionized disk associated with the torus produces a varying magnetic field across its surface. The varying magnetic field then induces a large electric field which accelerates particles to relativistic speeds. These particles spiral along the magnetic field lines and produce synchrotron radiation. Within AGN the radiation is emitted by a variety of sources, where some of the sources are thermal and others non-thermal. \citet{Burke_1997} states that the relative strength of these sources depends on the orientation of the AGN. The overall spectrum however, can be represented by a simple power law. It is widely held that radio sources in the Universe emit by the synchrotron process at lower radio frequencies in the meter and centimeter wavelength range \cite{Wielebinski_2006}. The radio core of an AGN emits synchrotron radiation emitted through particle acceleration and collimation into a double lobed structure. These are typical traits of radio galaxies. AGN also have a pair of jets of material ejected from their core. The structure of a radio source is also determined by the interaction of its energetic jets with ionized gas which surround the host galaxy. \citet{Krawczynski_2013}also  observe that the black holes in AGN accrete matter and convert the gravitational energy of the accreted matter (and possibly also the rotational energy of the black hole) into mechanical and electromagnetic energy. We also have that inside the accretion disk, a fraction of the gravitational energy of the accreted material is converted to heat and electromagnetic radiation which is then radiated away by the accretion disk. The jets are formed from a portion of the material processed through the accretion disk which escapes the accretion system as collimated and uncollimated outflows. Jet plasma velocity can be denoted by v where $v = \beta_{jet}*c \approx c $ ,and c represents the speed of light. $\Gamma_{jet}$ , the bulk Lorentz factor of the plasma is given by $ \Gamma_{jet} = (1 - (\beta_{jet})^2 )^{-1/2}$ . Emissions from the jets can be red or blue-shifted as a result of the relativistic Doppler factor $\delta_{jet} = \frac{1}{\Gamma_{jet} \times (1- \beta_{jet}\times\cos{\theta})}$ Where $\theta$ is the angle between the jet axis and the line of sight as measured in the observer frame \cite{Krawczynski_2013}. The lobes as seen in Figure 5 develop when the jets are stopped by pressure from the gas surrounding the host galaxy. The lobe structure is fairly symmetrical when viewed closer to the nucleus of the galaxy.  \citet{Burke_1997} states that the lobes derive energy from the jets, as the jets dissipate into the lobes and the total energy in the lobes can reach up to $10^{53} J$. Released gravitational energy of stellar material falling into a supermassive black hole an SMBH  is believed to be the main source of the galaxy’s energy. \citet{Mo_2009} theorizes that almost all spheroidal galaxy components (i.e., ellipticals and bulges) have a SMBH with a mass which correlated with that of the host galaxy, suggesting that the formation of SMBHs is related to the formation of their host galaxies.