A striking excess of red quasars with steep radio spectral slopes: a dusty blow-out phase revealed through AGN-driven shocks?

Ciera L. Sargent; David M. Alexander; Claire L. Greenwell; Victoria A. Fawcett; Leah K. Morabito; Chris M. Harrison; Moun Meenakshi; Ryan C. Hickox

arXiv · 2603.24739

A striking excess of red quasars with steep radio spectral slopes: a dusty blow-out phase revealed through AGN-driven shocks?

Ciera L. Sargent·David M. Alexander·Claire L. Greenwell·Victoria A. Fawcett·Leah K. Morabito·Chris M. Harrison·Moun Meenakshi·Ryan C. Hickox

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Abstract

Red quasars exhibit a higher incidence of compact (galaxy-scale or smaller) radio emission than blue quasars, arising from systems near the radio-loud/radio-quiet threshold. In this paper we select quasars from SDSS ($0.2 0.4$ mag) with steep slopes have radio luminosities consistent with the prediction from a wind-shock model with wind efficiencies of up to 7%. This agrees with the scenario where these compact red quasars are undergoing a "dusty blow-out" phase, where compact jets and/or AGN-driven winds interact with a dusty ISM, causing shocks, leading to steep spectral slopes and enhanced radio detection rates.

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Ciera L. Sargent, David M. Alexander, Claire L. Greenwell, Victoria A. Fawcett, Leah K. Morabito, Chris M. Harrison, Moun Meenakshi, Ryan C. Hickox. 2026-03-25. A striking excess of red quasars with steep radio spectral slopes: a dusty blow-out phase revealed through AGN-driven shocks?. https://arxiv.org/abs/2603.24739

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