Stellar and gas dynamics of interacting ring galaxies

The development of ring and arc structure due to the collision of a spherical galaxy normal to the plane of a disk galaxy is studied with analytic and numerical models. In the numerical model, the disk contains one-tenth of its mass in gas and the hydrodynamics equations are solved using the method of Smoothed Particle Hydrodynamics. It is found that axisymmetric collisions between equal mass galaxies produce a strong expanding ring with a complex three-dimensional structure. Density and velocity profiles for the disk are given. Off-center collisions produce greater gas density enhancements in the non-nuclear portion of the disk when compared to the axisymmetric case. Strong gas interactions in the off-center collisions cause the stellar and gaseous flows to follow separate trajectories. If star formation is associated with the strongest gas shocks and greatest gas densities, the morphology of ring galaxies is strongly dependent on a proper treatment of gas dynamical processes. A Rayleigh-Taylor instability is believed to be present in the strong shock regions, which could contribute to the knotty structure observed in ring galaxies.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2012

Author dc:creator

• Gerber, Richard Alan

Contributors dc:contributor

• Lamb, Susan A.

• ring galaxy
• axisymmetric collisions
• gas interactions

Statement dc:rights

• Copyright 1993 Richard Alan Gerber

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/28680

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/28680