Dynamical modelling of galactic disc outskirts

Abstract

I review briefly some dynamical models of structures in the outer parts of disc galaxies, including models of polar rings, tidal tails and bridges. I then discuss the density distribution in the outer parts of discs. For this, I compare observations to results of a model in which the disc galaxy is in fact the remnant of a major merger, and find good agreement. This comparison includes radial profiles of the projected surface density and of stellar age, as well as time evolution of the break radius and of the inner and outer disc scale lengths. I also compare the radial projected surface density profiles of dynamically motivated mono-age populations and find that, compared to older populations, younger ones have flatter density profiles in the inner region and steeper in the outer one. The break radius, however, does not vary with stellar age, again in good agreement with observations.

arXiv comment8 pages, 2 figures, invited review at IAU Symposium 321 "Formation and Evolution of Galaxy Outskirts", eds. A. Gil de Paz, J.C. Lee & J.H. Knapen

References in corpus (36)

• The Formation of Galactic Disks
• Secular Evolution and the Formation of Pseudobulges in Disk Galaxies
• The Formation of Disk Galaxies
• The Spitzer Survey of Stellar Structure in Galaxies (S^4G)
• Beyond Inside-Out Growth: Formation and Evolution of Disk Outskirts
• Anti-Truncation of Disks in Early-Type Barred Galaxies
• The Outer Disks of Early-Type Galaxies. I. Surface-Brightness Profiles of Barred Galaxies
• Tidal tails in CDM cosmologies
• Color Profiles of Spiral Galaxies: Clues on Outer-Disk Formation Scenarios
• Galaxy Collisions
• The impact of bars on disk breaks as probed by S4G imaging
• Forming disk galaxies in wet major mergers. I. Three fiducial examples
• Constraining Dark Halo Potentials with Tidal Tails
• The Flattened Dark Halo of Polar Ring Galaxy NGC 4650A: A Conspiracy of Shapes?
• Using Tidal Tails to Probe Dark Matter Halos
• Breaks in thin and thick discs of edge-on galaxies imaged in the Spitzer Survey of Stellar Structure in Galaxies (S4G)
• The Outer Disks of Early-Type Galaxies. II. Surface-Brightness Profiles of Unbarred Galaxies and Trends with Hubble Type
• The origin of polar ring galaxies: evidence for galaxy formation by cold accretion
• Outer-Disk Populations in NGC 7793: Evidence for Stellar Radial Migration
• Radial distribution of stars, gas and dust in SINGS galaxies. III. Modeling the evolution of the stellar component in galaxy disks
• Stellar populations across the NGC4244 truncated galactic disk
• Morphology and environment of galaxies with disc breaks in the S4G and NIRS0S
• The Formation of Polar Disk Galaxies
• Dissecting simulated disc galaxies I: the structure of mono-age populations
• Polar Ring Galaxies and the Tully Fisher relation: implications for the dark halo shape
• Color Profiles of Disk Galaxies since z~1: Probing Outer Disk Formation Scenarios
• Unveiling the Structure of Barred Galaxies at 3.6 $\mu \mathrm{m}$ with the Spitzer Survey of Stellar Structure in Galaxies (S${}^4$G): I. Disk Breaks
• How Does the Surface Density and Size of Disk Galaxies Measured in Hydrodynamic Simulations Correlate with the Halo Spin Parameter?
• Cosmic Evolution of Stellar Disk Truncations: From z~1 to the Local Universe
• Stellar Populations and Radial Migrations in Virgo Disk Galaxies
• The Structure of the Outer Galactic Disc as revealed by IPHAS early A Stars
• No direct coupling between bending of galaxy disc stellar age and light profiles
• The large extent of dark matter haloes probed by the formation of tidal dwarf galaxies
• Resonant capture, counter-rotating disks, and polar rings
• How to bend galaxy disc profiles: the role of halo spin
• The Halo Shape and Evolution of Polar Disc Galaxies