Quasar Outflows in the 4D Eigenvector 1 Context

TL;DR

This paper reviews how the 4D Eigenvector 1 scheme helps organize quasar outflow observations, providing insights into their physical and dynamical processes, and highlighting the diversity in outflow prominence among quasars.

Contribution

It introduces the application of the 4D Eigenvector 1 scheme to better understand and constrain quasar outflow properties and behaviors.

Findings

Outflows are common in quasars.

The 4D Eigenvector 1 scheme organizes outflow properties.

Diversity exists in outflow prominence among quasars.

Abstract

Gas outflows appear to be a phenomenon shared by the vast majority of quasars. Observations indicate that there is wide range in outflow prominence. In this paper we review how the 4D eigenvector 1 scheme helps to organize observed properties and lead to meaningful constraints on the outflow physical and dynamical processes.