Extended multiwavelength fuzz around red quasars: observational appearance of radiative feedback in action

TL;DR

This paper models how radiation pressure from red quasars drives dusty gas to expand, creating shocks that energize electrons, resulting in extended multiwavelength emission that reveals radiative feedback in action.

Contribution

It presents a theoretical framework linking quasar radiation pressure to shock-driven electron acceleration and multiwavelength emission, highlighting observable signatures of radiative feedback.

Findings

Shocks energize electrons to Lorentz factors of about 10^6.

Synchrotron emission peaks in near-infrared or UV bands.

Inverse Compton scattering produces gamma-ray emission around 1 GeV to 0.1 TeV.

Abstract

Red quasars are a population, characterized by significant extinction in UV, which could be explained by absorption of dusty gas on a scale of a few kpc. We show that the enhanced radiation-pressure drives the dusty gas to supersonically expand and produces shocks. The shocks energize electrons to be relativistic via the first Fermi acceleration. As a balance of shock acceleration and synchrotron emission and inverse Compton scattering, the maximum Lorentz factor of the electrons reaches as $\sim 10^6$. The shocked interstellar medium appears as extended multiwavelength fuzz, in which synchrotron emission from the electrons peaks at near infrared or UV bands and inverse Compton scattering around 1.0GeV$-$0.1TeV. Future multiwavelength images of the fuzz would provide new clues to study the details of radiative feedback if red quasars could be a certain phase in evolutionary chains of galaxies.