paper

Gas and stellar spiral structures in tidally perturbed disc galaxies

arXiv:1603.07801 · doi:10.1093/mnras/stw588

Abstract

Tidal interactions between disc galaxies and low mass companions are an established method for generating galactic spiral features. In this work we present a study of the structure and dynamics of spiral arms driven in interactions between disc galaxies and perturbing companions in 3-D N-body/smoothed hydrodynamical numerical simulations. Our specific aims are to characterize any differences between structures formed in the gas and stars from a purely hydrodynamical and gravitational perspective, and to find a limiting case for spiral structure generation. Through analysis of a number of different interacting cases, we find that there is very little difference between arm morphology, pitch angles and pattern speeds between the two media. The main differences are a minor offset between gas and stellar arms, clear spurring features in gaseous arms, and different radial migration of material in the stronger interacting cases. We investigate the minimum mass of a companion required to drive spiral structure in a galactic disc, finding the limiting spiral generation cases with companion masses of the order , equivalent to only 4% of the stellar disc mass, or 0.5% of the total galactic mass of a Milky Way analogue.

arXiv comment20 pages, 23 figures, accepted for publication by MNRAS

References in corpus (59)

Cited by in corpus (38)