Kinematic misalignment as a driver of black hole activity in galaxies with external interactions

TL;DR

This study investigates how kinematic misalignment of gas and stars in galaxies, especially those with external interactions, influences the likelihood of active galactic nuclei (AGN) activity, highlighting misaligned gas as a key fueling mechanism.

Contribution

It is the first to quantify the impact of kinematic misalignment on AGN activity in a large galaxy sample, showing its significance beyond external interactions.

Findings

Higher AGN fraction in galaxies with large kinematic misalignment.

Gas-stellar misalignment significantly increases AGN likelihood.

Misaligned structures are crucial for supermassive black hole fueling.

Abstract

The process of Active Galactic Nuclei (AGN) fuelling relies on the transport of gas across several orders of magnitude in physical scale until the gas reaches the supermassive black hole at the centre of a galaxy. This work explores the role of kinematically misaligned gas in the fuelling of AGN in a sample of 4769 local galaxies from the MaNGA survey. We investigate for the first time the relative role of external interactions and the presence of kinematic misalignment as mechanisms to explain the observed increase in AGN fraction in galaxies with large stellar to gas kinematic misalignment ($>$45 degrees). Using a sample of galaxies with evidence of recent external interactions we find that there is a significantly higher fraction of AGN in those where a large stellar to gas kinematic misalignment is observed (20$^{+6}_{-4}\%$) compared with 6.2$^{+0.6}_{-0.5}\%$ in galaxies where no kinematic misalignment is observed. We determine that gas to stellar misalignment has an important role in the fraction of AGN observed, increasing the AGN fraction beyond the potential effect of external interactions. This result demonstrates the importance of misaligned structures to the fuelling of supermassive black holes.