VLT/UVES Observation of the SDSS J2357-0048 Outflow

TL;DR

This study analyzes a quasar's outflow using VLT/UVES spectra, identifying multiple absorption components, measuring ion column densities, and assessing the outflow's potential role in AGN feedback, including variability over time.

Contribution

It provides detailed spectral analysis of a quasar outflow, measuring ion column densities and kinetic luminosity, and reports on the variability of absorption features over several years.

Findings

Identified four subcomponents of the BAL outflow.

Measured ion column densities including O I and Fe II.

Estimated the outflow's kinetic luminosity near the threshold for AGN feedback.

Abstract

We found a broad absorption line (BAL) outflow in the VLT/UVES spectrum of the quasar SDSS J235702.54-004824.0, in which we identified four subcomponents. We measured the column densities of the ions in one of the subcomponents ($v$ = -1600 km s$^{-1}$), which include O I and Fe II. We found the kinetic luminosity of this component to be at most ~2.4% of the quasar's Eddington luminosity. This is near the amount required to contribute to AGN feedback. We also examined the time-variability of a C IV mini-BAL found at $v$ = -8700 km s$^{-1}$, which shows a shallower and narrower absorption feature attached to it in previous SDSS observations from 2000 and 2001, but not in the spectra from 2005 and onwards.