# AGN radiative feedback in dusty quasar populations

## TL;DR

This paper investigates how AGN radiative feedback, via radiation pressure on dust, influences the evolution and observational features of dusty quasars, explaining prolonged obscuration and extreme outflows observed in high-redshift populations.

## Contribution

It introduces shell models of radiation pressure-driven feedback to explain diverse dusty quasar phenomena and their evolutionary stages.

## Key findings

- Expanding shells can cause prolonged obscuration lasting millions of years.
- Fixed-mass shells with high dust-to-gas ratios explain extreme outflows in red quasars.
- Interaction with ambient medium influences observational appearance of dusty quasars.

## Abstract

New populations of hyper-luminous, dust-obscured quasars have been recently discovered around the peak epoch of galaxy formation ($z \sim 2-3$), in addition to similar sources found at lower redshifts. Such dusty quasars are often interpreted as sources `in transition', from dust-enshrouded starbursts to unobscured luminous quasars, along the evolutionary sequence. Here we consider the role of the active galactic nucleus (AGN) radiative feedback, driven by radiation pressure on dust, in high-luminosity, dust-obscured sources. We analyse how the radiation pressure-driven dusty shell models, with different shell mass configurations, may be applied to the different populations of dusty quasars reported in recent observations. We find that expanding shells, sweeping up matter from the surrounding environment, may account for prolonged obscuration in dusty quasars, e.g. for a central luminosity of $L \sim 10^{47}$erg/s, a typical obscured phase (with extinction in the range $A_{V} \sim 1-10$ mags) may last a few $\sim 10^6$yr. On the other hand, fixed-mass shells, coupled with high dust-to-gas ratios, may explain the extreme outflows recently discovered in red quasars at high redshifts. We discuss how the interaction between AGN radiative feedback and the ambient medium at different temporal stages in the evolutionary sequence may contribute to shape the observational appearance of dusty quasar populations.