The nuclear environment of NGC 2442: a Compton-thick low-luminosity AGN

TL;DR

This study combines optical, X-ray, and HST data to reveal a Compton-thick low-luminosity AGN in NGC 2442, showing outflows and suppressed star formation in its nucleus.

Contribution

It provides a multiwavelength analysis confirming the presence of a Compton-thick AGN and its impact on the host galaxy's nuclear environment.

Findings

Detection of a Compton-thick AGN in NGC 2442

Identification of ionization cone and outflows

Absence of recent star formation in the nucleus

Abstract

The detailed study of nuclear regions of galaxies is important because it can help understanding the active galactic nucleus (AGN) feedback mechanisms, the connections between the nuclei and their host galaxies, and ultimately the galaxy formation processes. We present the analysis of an optical data cube of the central region of the galaxy NGC 2442, obtained with the integral field unit (IFU) of the Gemini Multi-Object Spectrograph (GMOS). We also performed a multiwavelength analysis, with Chandra data, XMM--Newton and NuSTAR spectra, and Hubble Space Telescope (HST) images. The analysis revealed that the nuclear emission is consistent with a Low Ionization Nuclear Emission-line Region (LINER) associated with a highly obscured compact hard X-ray source, indicating a Compton-thick AGN. The HST image in the F658N filter (H$\alpha$) reveals an arched structure corresponding to the walls of the ionization cone of the AGN. The gas kinematic pattern and the high gas velocity dispersion values in the same region of the ionization cone suggest an outflow emission. The stellar archaeology results indicate the presence of only old stellar populations ($\sim$ 10 Gyr), with high metallicity (z = 0.02 and 0.05), and the absence of recent star formation in the central region of NGC 2442, which is possibly a consequence of the AGN feedback, associated with the detected outflow, shutting off star formation. NGC 2442 is a late-type galaxy similar to the Milky Way, and comparisons show that the main difference between them is the presence of a low-luminosity AGN.