Angular Momentum Redistribution and the Evolution and Morphology of Bars

Abstract

Angular momentum exchange is a driving process for the evolution of barred galaxies. Material at resonance in the bar region loses angular momentum which is taken by material at resonance in the outer disc and/or the halo. By losing angular momentum, the bar grows stronger and slows down. This evolution scenario is backed by both analytical calculations and by N-body simulations. The morphology of the bar also depends on the amount of angular momentum exchanged.