Pattern speed evolution of barred galaxies in TNG50

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Semczuk, Marcin, Dehnen, Walter, Schönrich, Ralph, Athanassoula, E.
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917864637726720
author Semczuk, Marcin
Dehnen, Walter
Schönrich, Ralph
Athanassoula, E.
author_facet Semczuk, Marcin
Dehnen, Walter
Schönrich, Ralph
Athanassoula, E.
contents Galactic bars are found in the majority of disc galaxies. They rotate nearly rigidly with an angular frequency called pattern speed. Previous idealised simulations have shown that bar pattern speed decreases with time due to dynamical friction exerted by the dark matter halo, while cold gas can reduce or even reverse this trend. We want to understand how different galaxy properties affect the evolution of the bar pattern speed in more realistic situations, including ongoing star formation, mass infall, AGN feedback and galaxy interactions. We used the high-resolution run TNG50-1 of the magnetohydrodynamical cosmological simulations suite IllustrisTNG to trace the pattern speed of simulated bars and see how it depends on various galaxy properties. Simulated bars with initially high pattern speed and a subsequent rapid slowdown are more likely found in more massive galaxies. Lower mass galaxies, on the other hand, preferentially host bars that start at relatively low pattern speeds and retain the same value until the end of the simulation. More massive barred galaxies are also more affected by the AGN feedback, which removes (or heats up) the cold gas that could have prevented the slowdown. We find that bars grow and strengthen with slowdown, in agreement with higher resolution simulations. We find that strong correlations between the bar slowdown rate and galaxy mass weaken considerably when we use dimensionless measures to quantify the slowdown. In TNG50, the AGN feedback prescription amplifies the mass dependence. Turned around, this provides an interesting statistic to constrain subgrid physics by bar growth/slowing.
format Preprint
id arxiv_https___arxiv_org_abs_2407_11154
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Pattern speed evolution of barred galaxies in TNG50
Semczuk, Marcin
Dehnen, Walter
Schönrich, Ralph
Athanassoula, E.
Astrophysics of Galaxies
Galactic bars are found in the majority of disc galaxies. They rotate nearly rigidly with an angular frequency called pattern speed. Previous idealised simulations have shown that bar pattern speed decreases with time due to dynamical friction exerted by the dark matter halo, while cold gas can reduce or even reverse this trend. We want to understand how different galaxy properties affect the evolution of the bar pattern speed in more realistic situations, including ongoing star formation, mass infall, AGN feedback and galaxy interactions. We used the high-resolution run TNG50-1 of the magnetohydrodynamical cosmological simulations suite IllustrisTNG to trace the pattern speed of simulated bars and see how it depends on various galaxy properties. Simulated bars with initially high pattern speed and a subsequent rapid slowdown are more likely found in more massive galaxies. Lower mass galaxies, on the other hand, preferentially host bars that start at relatively low pattern speeds and retain the same value until the end of the simulation. More massive barred galaxies are also more affected by the AGN feedback, which removes (or heats up) the cold gas that could have prevented the slowdown. We find that bars grow and strengthen with slowdown, in agreement with higher resolution simulations. We find that strong correlations between the bar slowdown rate and galaxy mass weaken considerably when we use dimensionless measures to quantify the slowdown. In TNG50, the AGN feedback prescription amplifies the mass dependence. Turned around, this provides an interesting statistic to constrain subgrid physics by bar growth/slowing.
title Pattern speed evolution of barred galaxies in TNG50
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2407.11154