Decoupling the rotation of stars and gas -- II: the link between black hole activity and MaNGA kinematics in TNG

TL;DR

This study investigates how supermassive black hole activity influences the misalignment between stellar and gas kinematics in galaxies, revealing correlations with black hole luminosity, gas properties, and galaxy mass over billions of years.

Contribution

It provides new insights into the link between black hole feedback and galaxy kinematic misalignment using simulated MaNGA-like observations in the IllustrisTNG simulation.

Findings

Low mass misaligned galaxies have higher black hole luminosity and energy injection.

Misalignment correlates with black hole activity over 8 Gyrs, especially in low mass galaxies.

High mass misaligned galaxies show no significant gas loss and lower metallicity, indicating external gas origin.

Abstract

We study the relationship between supermassive black hole (BH) feedback, BH luminosity and the kinematics of stars and gas for galaxies in IllustrisTNG. We use a sample of galaxies with mock MaNGA observations to identify kinematic misalignment at $z=0$ (difference in rotation of stars and gas), for which we follow the evolutionary history of BH activity and gas properties over the last 8 Gyrs. Misaligned low mass galaxies typically have boosted BH luminosity, BH growth and have had more energy injected into the gas over the last 8 Gyr in comparison to aligned galaxies. These properties likely lead to outflows and gas loss, in agreement with active low mass galaxies in observations. We show that splitting on BH luminosity at $z=0$ produces statistically consistent distributions of kinematic misalignment at $z=0$, however, splitting on the maximum BH luminosity over the last 8 Gyrs does not. While instantaneous correlation at $z=0$ is difficult due to misalignment persisting on longer timescales, the relationship between BH activity and misalignment is clear. High mass quenched galaxies with misalignment typically have similar BH luminosities, show no overall gas loss, and have typically lower gas phase metallicity over the last 8 Gyrs in comparison to those aligned; suggesting external origin.