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\subsection{AGN feedback in galaxies}  Feedback encompasses a wide range of astrophysics, including radiation from stars heating and ionizing surrounding gas, thermal and kinetic energy injection from supernova explosions, heating from active galactic nuclei (AGN), and the impact of AGN jets. These processes can drive galactic winds, blowing gas out of galaxies, and slowing down star formation. Although SMBH have been suggested as a highly efficient mechanism for regulating star formation in galaxies, \cite{Borys_2005} suggest that direct evidence for feedback, in particular due to SMBH activity, activity  is scarce. Accretion onto SMBHs can release tremendous amounts of energy that can potentially drive large-scale outflows, and quenchthe  star formation. Accretion is an important feedback source for galaxy formation as it releases vast amounts of energy – this is why AGN have high luminosities. \cite{Karouzos_2013} provides evidence for the existence of a positive correlation between the luminosity of the AGN component of a host galaxy and the host’s star-formation. This is said to be independent of the radio luminosity. It was also discovered that high radio-luminosities are associated with a decrease in star-formation rate \cite{Mo_2009}. Analytical models of galaxy formation that use cosmological N-body simulations have revealed that AGN feedback can be responsible for creating a population of red and dead massive galaxies \cite{Mo_2009}. Hot gas, cold gas, stars, and a supermassive black hole an SMBH  are the main components of a galaxy. Cooling, star formation, AGN accretion and feedback processes can transfer particles from one component to another, and in that way alter the efficiency of all the processes in the galaxy. For example, increased cooling of hot gas will lead to the production of more cold gas. This in turn increases the star formation rate, therefore increasing the rate of supernovae. Energy released by supernovae and ejections from AGN jets and reheats cold gas.This leads to a suppression of star formation (negative feedback). In contrast, supernova blast-waves may also compress the surrounding cold gas, thus increasing star formation rate (positive feedback). The formation and evolution of galaxies depends on these feedback loops \cite{Mo_2009}. Studies have shown that there is a link between the mass of a central SMBH and that of its host galaxies. It is further observed that the black hole accretion rate and star formation rate of the host galaxy both peak at a similar redshift. Both accretion of gas (for the SMBH) and star formation (for the host galaxy) are fueled by a supply of gas. These mechanisms show that there is a link between the growth of SMBH with their host galaxies \cite{Chen_2013} \cite{Chen_2013}.