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تسجيل مستخدم جديدPowerful winds in high-redshift obscured and red quasars
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Quasar-driven outflows must have made their most significant impact on galaxy formation during the epoch when massive galaxies were forming most rapidly. To study the impact of quasar feedback we conducted rest-frame optical integral field spectrograph (IFS) observations of three extremely red quasars (ERQs) and one type-2 quasar at $z=2-3$, obtained with the NIFS and OSIRIS instruments at the Gemini North and W. M. Keck Observatory with the assistance of laser-guided adaptive optics. We use the kinematics and morphologies of the [OIII] 5007AA and H$alpha$ 6563AA emission lines redshifted into the near-infrared to gauge the extents, kinetic energies and momentum fluxes of the ionized outflows in the quasars host galaxies. For the ERQs, the galactic-scale outflows are likely driven by radiation pressure in a high column density environment or due to an adiabatic shock. For the type-2 quasar, the outflow is driven by radiation pressure in a low column density environment or due to a radiative shock. The outflows in the ERQs carry a significant amount of energy ranging from 0.05-5$%$ of the quasars bolometric luminosity, powerful enough to have a significant impact on the quasar host galaxies. However, the outflows are likely only impacting the inner few kpc of each host galaxy. The observed outflow sizes are generally smaller than other ionized outflows observed at high redshift. The high ratio between the momentum flux of the ionized outflow and the photon momentum flux from the quasar accretion disk and high nuclear obscuration makes these ERQs great candidates for transitional objects where the outflows are likely responsible for clearing material in the inner regions of each galaxy, unveiling the quasar accretion disk at optical wavelengths.
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