Integral field spectroscopy of type-II QSOs at z=0.3-0.4

TL;DR

This study uses integral-field spectroscopy to analyze six type-II QSOs at z=0.3-0.4, revealing extended ionized gas nebulae, complex kinematics, and evidence of outflows and ionization mechanisms.

Contribution

First integral-field spectroscopic analysis of six type-II QSOs at intermediate redshift, uncovering nebulae, kinematic complexities, and outflows.

Findings

Two QSOs have nebulae extending up to 40 kpc.

Detected outflows approximately 20 kpc in size.

Evidence of shock and AGN radiation ionization.

Abstract

We present and analyse integral-field observations of six type-II QSOs with z=0.3-0.4, selected from the Sloan Digital Sky Survey (SDSS). Two of our sample are found to be surrounded by a nebula of warm ionized gas, with the largest nebula extending across 8" (40 kpc). Some regions of the extended nebulae show kinematics that are consistent with gravitational motion, while other regions show relatively perturbed kinematics: velocity shifts and line widths too large to be readily explained by gravitational motion. We propose that a ~20 kpc x20 kpc outflow is present in one of the galaxies. Possible mechanisms for triggering the outflow are discussed. In this object, we also find evidence for ionization both by shocks and the radiation field of the AGN.