# Star formation in AGNs at the hundred parsec scale using MIR high resolution images

## TL;DR

This study investigates circumnuclear star formation in 15 AGNs at scales of tens of parsecs using high-resolution mid-infrared imaging, revealing correlations with AGN luminosity and unexpected starburst activity in low-luminosity AGNs.

## Contribution

It provides high-resolution MIR observations of circumnuclear star formation in AGNs and explores its relationship with AGN activity, especially at small scales.

## Key findings

- Nearly half of the AGNs show circumnuclear star formation within tens of parsecs.
- Star formation luminosity correlates with AGN luminosity for high-luminosity AGNs.
- Low-luminosity AGNs exhibit starburst luminosities exceeding their bolometric luminosities.

## Abstract

It has been well established in the past decades that the central black hole masses of galaxies correlate with dynamical properties of their harbouring bulges. This notion begs the question of whether there are causal connections between the AGN and its immediate vicinity in the host galaxy. In this paper we analyse the presence of circumnuclear star formation in a sample of 15 AGN using mid-infrared observations. The data consist of a set of 11.3{\mm} PAH emission and reference continuum images, taken with ground based telescopes, with sub-arcsecond resolution. By comparing our star formation estimates with AGN accretion rates, derived from X-ray luminosities, we investigate the validity of theoretical predictions for the AGN-starburst connection. Our main results are: i) circumnuclear star formation is found, at distances as low as tens of parsecs from the nucleus, in nearly half of our sample (7/15); ii) star formation luminosities are correlated with the bolometric luminosity of the AGN ($L_{AGN}$) only for objects with $L_{AGN} \ge 10^{42}\,\,{\rm erg\,\,s^{-1}}$; iii) low luminosity AGNs ($L_{AGN} < 10^{42}\,\,{\rm erg\,\,s^{-1}}$) seem to have starburst luminosities far greater than their bolometric luminosities.