Off-Axis Energy Variability of AGNs: a New Paradigm for Broad-Line- and Continuum-Emitting Regions

TL;DR

This paper proposes that off-axis variability in AGNs explains various observational puzzles related to emission line profiles, variability patterns, and polarization, challenging previous exotic explanations.

Contribution

It introduces off-axis variability as a unifying paradigm to explain complex AGN observational phenomena without resorting to exotic models.

Findings

Off-axis variability accounts for asymmetric emission lines.

Explains inconsistent multi-wavelength variability.

Clarifies polarization and gas flow changes.

Abstract

The general picture of how thermal AGNs work has become clearer in recent years but major observational puzzles threaten to undermine this picture. These puzzles include AGNs with extremely asymmetric emission line profiles, inconsistent multi-wavelength variability, rapid apparent changes in the sizes of emitting regions and in the direction of gas flow, a curious insensitivity of gas in some narrow velocity ranges to changes in the ionizing continuum, and differing dependencies of polarization on gas velocity. It is proposed that all these puzzles can readily be explained by off-axis variability, and that there is no need to invoke exotic explanations such as binary supermassive black holes or recoiling black holes.