Journal Article

Radial migration in disc galaxies — I. Transient spiral structure and dynamics

Rok Roškar, Victor P. Debattista, Thomas R. Quinn and James Wadsley

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 426, issue 3, pages 2089-2106
Published in print November 2012 | ISSN: 0035-8711
Published online November 2012 | e-ISSN: 1365-2966 | DOI: http://dx.doi.org/10.1111/j.1365-2966.2012.21860.x
Radial migration in disc galaxies — I. Transient spiral structure and dynamics

Show Summary Details

Preview

Abstract

We seek to understand the origin of radial migration in spiral galaxies by analysing in detail the structure and evolution of an idealized, isolated galactic disc. To understand the redistribution of stars, we characterize the time evolution of properties of spirals that spontaneously form in the disc. Our models unambiguously show that in such discs, single spirals are unlikely, but that a number of transient patterns may coexist in the disc. However, we also show that while spirals are transient in amplitude, at any given time the disc favours patterns of certain pattern speeds. Using several runs with different numerical parameters we show that the properties of spirals that occur spontaneously in the disc do not sensitively depend on resolution. The existence of multiple transient patterns has large implications for the orbits of stars in the disc, and we therefore examine the resonant scattering mechanisms that profoundly alter angular momenta of individual stars. We confirm that the corotation scattering mechanism described by Sellwood & Binney is responsible for the largest angular momentum changes in our simulations.

Keywords: galaxies: evolution; galaxies: formation; galaxies: kinematics and dynamics; galaxies: spiral; galaxies: structure

Journal Article.  13222 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.