Quasar massive ionized outflows traced by CIV {\lambda}1549 and [OIII]{\lambda}{\lambda}4959,5007

TL;DR

This paper reviews evidence of powerful ionized outflows in luminous quasars, highlighting their potential impact on galaxy evolution through feedback mechanisms, based on emission line blueshifts and related measurements.

Contribution

It provides a synthesis of recent findings on quasar outflows, emphasizing their nuclear origin and significant feedback effects on host galaxies at high redshifts.

Findings

High prevalence of blueshifted CIV and [OIII] emission lines in luminous quasars

Ionized gas outflows have extremely high mass and kinetic power

Outflows suggest widespread feedback effects on host galaxies

Abstract

The most luminous quasars (with bolometric luminosities are 1E47 erg/s) show a high prevalence of CIV {\lambda}1549 and [OIII]{\lambda}{\lambda}4959,5007 emission line profiles with strong blueshifts. Blueshifts are interpreted as due to Doppler effect and selective obscuration, and indicate outflows occurring over a wide range of spatial scales. We found evidence in favor of the nuclear origin of the outflows diagnosed by [OIII]{\lambda}{\lambda} 4959,5007. The ionized gas mass, kinetic power, and mechanical thrust are extremely high, and suggest widespread feedback effects on the host galaxies of very luminous quasars, at cosmic epochs between 2 and 6 Gyr from the Big Bang. In this mini-review we summarize results obtained by our group and reported in several major papers in the last few years with an eye on challenging aspects of quantifying feedback effects in large samples of quasars.