Order and chaos in a galactic model with a strong nuclear bar

Abstract

We use a composite gravitational galactic model consisting of a disk, a halo, a massive nucleus and a strong nuclear bar, in order to study the connections between global and local parameters in a realistic dynamical system. The local model is constructed from a two-dimensional perturbed harmonic oscillator and can be derived by expanding the global model in the vicinity of the central stable Lagrange equilibrium point. The frequencies of oscillations are not arbitrary, but they are connected with all the parameters involved with the global model. Moreover, the value of the local energy is also connected with the value of the global energy. Low and high energy stars in the global model display chaotic motion. Comparison with previous research reveals that the presence of the massive nucleus is responsible for the chaotic motion of the low energy stars. In the local motion, the low energy stars show interesting resonance phenomena, but the chaotic motion, if any, is negligible. On the contrary, the high energy stars do not show bounded motion in the local model. This is an indication of particular activity near the center of galaxies possessing massive nuclei.

Published in Research in Astronomy and Astrophysics (RAA) journal

References in corpus (4)

• The Destruction of Bars by Central Mass Concentrations
• Using Hubble Space Telescope Imaging of Nuclear Dust Morphology to Rule Out Bars Fueling Seyfert Nuclei
• The nature of orbits in a prolate elliptical galaxy model with a bulge and a dense nucleus
• Comparing the behavior of orbits in different 3D dynamical models for elliptical galaxies

Cited by in corpus (7)

• Spending too much time at the Galactic bar: chaotic fanning of the Ophiuchus stream
• Fractal basins of escape and the formation of spiral arms in a galactic potential with a bar
• Orbital and escape dynamics in barred galaxies - I. The 2D system
• Role of galactic bars in the formation of spiral arms: A study through orbital and escape dynamics -- I
• Escape dynamics and fractal basin boundaries in Seyfert galaxies
• Effect of dark matter halos on the orbital and escape dynamics of barred galaxies
• Fractal Measures and Nonlinear Dynamics of Overcontact Binaries