Spatially resolved analysis of Stellar Populations in NGC 2992: Impact of AGN feedback

TL;DR

This study uses spatially resolved data from VLT/MUSE to analyze stellar populations in NGC 2992, revealing how AGN-driven outflows influence star formation and stellar ages across the galaxy.

Contribution

It presents the first detailed spatial analysis of stellar populations in NGC 2992, linking AGN feedback to both suppression and enhancement of star formation.

Findings

Young stellar populations are found within the dust lane and along the galaxy's major axis.

The distribution of young stars is anti-correlated with the AGN outflow cone.

Evidence suggests AGN outflows can exert both negative and positive feedback on star formation.

Abstract

In NGC 2992, a galaxy-scale ionized gas outflow driven by AGN has long been recognized, yet its impact on the host galaxy has remained elusive. In this paper, we utilize data from the archival Very Large Telescope (VLT)/MUSE to present a spatially resolved analysis of stellar populations in this galaxy. Two different stellar population templates are employed to fit the stellar continuum, allowing us to determine the light-weighted stellar age, metallicity, the fraction of the young stellar population (age $<100$ Myr, $P_{\rm Y}$), and the average age and metallicity of $P_{\rm Y}$. Our results reveal the presence of a very young stellar population ($\leq40$ Myr) within the dust lane and nearly along the galaxy's major axis. The light-weighted stellar age and the fraction of $P_{\rm Y}$ show negative trends along the major and minor axes. The average age and metallicity of $P_{\rm Y}$ present positive trends with increasing distance, except along the northern direction of the major axis. Within the circumnuclear region ($<1$ kpc), the distribution of the young stellar population is spatially anti-correlated with the AGN outflow cone. The highest fraction of $P_{\rm Y}$ is observed at the outskirts of the nuclear radio bubble in the northern region near the nucleus. Considering the coupling efficiency and timescales, we propose that the AGN outflow in this galaxy may exert both negative and positive feedback on its host. Additionally, the star formation and the AGN activities could be attributed to the interaction between NGC 2992 and NGC 2993.