I investigate the effects of AGN feedback on galaxy evolution by studying quasars at cosmic noon (1 ≲ z ≲ 3), when AGN and star formation activity peak, leading to extreme outflows. These luminous quasars are no longer present in the local Universe, and outflows at later cosmic epochs are weaker. My research involves analyzing high-luminosity quasars (1.5 ≲ z ≲ 4) through UV and optical emission lines. 

By performing an intercomparison between the different emission lines, we found that both [O III] and C IV outflows show very high amplitudes and a high degree of correlation between themselves, which may suggest a possible physical connection between an inner outflow on scales of a few hundreds gravitational radii where C IV is emitted and an outer outflow, beyond 10^4 − 10^5 gravitional radii where the [O III] emission likely originates (see Fig. 1). In addition, the line widths and shifts are correlated for both the [O III] and C IV outflow components, which suggests that the outflowing gas is somehow providing a substantial broadening effect to both lines.

In Deconto-Machado et al. (2024), we evaluate the relation between the outflows and the radio emission. We found that high-ionization lines especially in radio-quiet sources usually present a significant asymmetry toward the blue that is strong evidence of outflow motions. In contrast, radio-loud quasars tend to have modest outflowing components and more symmetric profiles in both the UV and optical ranges. Our analysis suggests that the radio emission somehow contributes to smaller outflows and that the strongest outflows in both [O III] and C IV are caused mainly by the accretion due to a central SMBH.

About 10% of the galaxies in our Universe are expected to present an active galactic nucleus (AGN). This phenomenon occurs when a supermassive black hole (SMBH) in the center of the galaxy captures the nearby matter. During this process, this matter is gradually accreted, turning gravitational potential energy into electromagnetic radiation and kinetic energy, by the ejection of particles in the form of winds. Understanding the process of gas accretion due to the SMBH activity and its impact on the host galaxy is key to advance our understanding of the processes of galaxy evolution.

Assuming that the stellar motions are dominated by the gravitational potential of the galaxies, we can compare the gas and stellar kinematics in order to isolate non-circular motions of gas, which usually can be attributed to outflows driven by a central AGN. In Deconto-Machado et al. (2022), we studied the stellar and gas kinematics of low-redshift (≲ 0.2) 112 Active Galactic Nuclei (AGN) from the SDSS-IV MaNGA together with a control sample and determined the spatial scale and the kinetic power of the [O III]λ5007 outflows. Our analysis reveals that although the kinematic disturbance on the narrow-line region (NLR) by the AGN extends up to several kpc in some galaxies, its effect is not powerful enough to significantly affect their host galaxies.