open access

https://hdl.handle.net/2115/68609

Bars and spirals in tidal interactions with an ensemble of galaxy mass models

英語

galaxies: structure

2018-03-11

Oxford University Press

Monthly notices of the royal astronomical society

474(4)

5645-5671

We present simulations of the gaseous and stellar material in several different galaxy mass models under the influence of different tidal fly-bys to assess the changes in their bar and spiral morphology. Five different mass models are chosen to represent the variety of rotation curves seen in nature. We find a multitude of different spiral and bar structures can be created, with their properties dependent on the strength of the interaction. We calculate pattern speeds, spiral wind-up rates, bar lengths, and angular momentum exchange to quantify the changes in disc morphology in each scenario. The wind-up rates of the tidal spirals follow the 2:1 resonance very closely for the flat and dark matter-dominated rotation curves, whereas the more baryon-dominated curves tend to wind-up faster, influenced by their inner bars. Clear spurs are seen in most of the tidal spirals, most noticeable in the flat rotation curve models. Bars formed both in isolation and interactions agree well with those seen in real galaxies, with a mixture of ‘fast’ and ‘slow’ rotators. We find no strong correlation between bar length or pattern speed and the interaction strength. Bar formation is, however, accelerated/induced in four out of five of our models. We close by briefly comparing the morphology of our models to real galaxies, easily finding analogues for nearly all simulations presenter here, showing passages of small companions can easily reproduce an ensemble of observed morphologies.

学術雑誌論文

Version of Record

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©:2018 Alex R. Pettitt, J. W. Wadsley. Published by Oxford University Press on behalf of The Royal Astronomical Society. All rights reserved.

0035-8711

AA10528285