Facial reconstruction

Search LJMU Research Online

Browse Repository | Browse E-Theses

Vertical disc heating in milky way-sized galaxies in a cosmological context

Grand, RJJ, Springel, V, Gómez, FA, Marinacci, F, Pakmor, R, Campbell, DJR and Jenkins, A (2016) Vertical disc heating in milky way-sized galaxies in a cosmological context. Monthly Notices of the Royal Astronomical Society, 459 (1). pp. 199-219. ISSN 0035-8711

stw601.pdf - Published Version

Download (4MB) | Preview


Vertically extended, high velocity dispersion stellar distributions appear to be a ubiquitous feature of disc galaxies, and both internal and external mechanisms have been proposed to be the major driver of their formation. However, it is unclear to what extent each mechanism can generate such a distribution, which is likely to depend on the assembly history of the galaxy. To this end, we perform 16 high-resolution cosmological-zoom simulations of Milky Way-sized galaxies using the state-of-the-art cosmological magnetohydrodynamical code arepo, and analyse the evolution of the vertical kinematics of the stellar disc in connection with various heating mechanisms. We find that the bar is the dominant heating mechanism in most cases, whereas spiral arms, radial migration and adiabatic heating from mid-plane density growth are all subdominant. The strongest source, though less prevalent than bars, originates from external perturbations from satellites/subhaloes of masses log10(M/M⊙) ≳ 10. However, in many simulations the orbits of newborn star particles become cooler with time, such that they dominate the shape of the age-velocity dispersion relation and overall vertical disc structure unless a strong external perturbation takes place.

Item Type: Article
Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
Uncontrolled Keywords: 0201 Astronomical and Space Sciences; Astronomy & Astrophysics
Subjects: Q Science > QB Astronomy
Q Science > QC Physics
Divisions: Astrophysics Research Institute
Publisher: Oxford University Press (OUP)
SWORD Depositor: A Symplectic
Date Deposited: 19 Apr 2023 10:56
Last Modified: 19 Apr 2023 10:56
DOI or ID number: 10.1093/mnras/stw601
URI: https://researchonline.ljmu.ac.uk/id/eprint/19352
View Item View Item