Classifying orbits in galaxy models with a prolate or an oblate dark matter halo component

Abstract

We explore the nature of orbits of stars moving in the meridional plane $(R,z)$ of an axially symmetric galactic model with a disk, a spherical nucleus, and a flat biaxial dark matter halo component. In particular, we study the influence of all the involved parameters of the dynamical system, by computing both the percentage of chaotic orbits and the percentages of orbits of the main regular resonant families in each case. To distinguish between ordered and chaotic motion, we use the smaller alignment index (SALI) method to extensive samples of orbits by numerically integrating the equations of motion as well as the variational equations. Moreover, a method based on the concept of spectral dynamics that utilizes the Fourier transform of the time series of each coordinate is used to identify the various families of regular orbits and also to recognize the secondary resonances that bifurcate from them. Two cases are studied for every parameter: (i) the case where the halo component is prolate and (ii) the case where an oblate dark halo is present. Our numerical investigation indicates that all the dynamical quantities affect, more or less, the overall orbital structure. It was observed that the mass of the nucleus, the halo flattening parameter, the scale length of the halo, the angular momentum, and the orbital energy are the most influential quantities, while the effect of all the other parameters is much weaker. It was also found that all the parameters corresponding to the disk only have a minor influence on the nature of orbits. Furthermore, some other quantities, such as the minimum distance to the origin, the horizontal, and the vertical force, were tested as potential chaos detectors. Our analysis revealed that only general information can be obtained from these quantities. We also compared our results with early related work.

arXiv commentPublished in Astronomy & Astrophysics (A&A) journal

References in corpus (34)

• A Universal Density Profile from Hierarchical Clustering
• The Structure of Cold Dark Matter Halos
• Concentrations of Dark Halos from their Assembly Histories
• Triaxial Modeling of Halo Density Profiles with High-resolution N-body Simulations
• The Shape of Dark Matter Halos: Dependence on Mass, Redshift, Radius, and Formation
• Dynamics of Barred Galaxies
• Milky Way Mass Models for Orbit Calculations
• The Kinematic Connection Between QSO-Absorbing Gas and Galaxies at Intermediate Redshift
• Shapes and Alignments of Galaxy Cluster Halos
• Triaxial Galaxies with Cusps
• Orbital dynamics of three-dimensional bars: I. The backbone of 3D bars. A fiducial case
• Evidence in Virgo for the Universal Dark Matter Halo
• Two measures of the shape of the Milky Way's dark halo
• ROTATION CURVES OF 967 SPIRAL GALAXIES
• Elliptical Galaxy Dynamics
• On the identification of merger debris in the {\it Gaia} Era
• A Detection of Dark Matter Halo Ellipticity using Galaxy Cluster Lensing in SDSS
• Reconstructing the cosmic density field with the distribution of dark matter halos
• Models for the Gravitational Field of the Galactic Bar. An Application to Stellar Orbits in the Galactic Plane and Orbits of Some Globular Clusters
• Orbital dynamics of three-dimensional bars: II. Investigation of the parameter space
• Regular and chaotic orbits in barred galaxies - I. Applying the SALI/GALI method to explore their distribution in several models
• Self-consistent models of cuspy triaxial galaxies with dark matter haloes
• Galaxy Clusters: Oblate or Prolate?
• A new dynamical model for the study of galactic structure
• Orbit classification in the meridional plane of a disk galaxy model with a spherical nucleus
• Interplay Between Chaotic and Regular Motion in a Time-Dependent Barred Galaxy Model
• Exploring the nature of orbits in a galactic model with a massive nucleus
• Complex statistics in Hamiltonian barred galaxy models
• Revealing the influence of dark matter on the nature of motion and the families of orbits in axisymmetric galaxy models
• The evolution of chaos in active galaxy models with an oblate or a prolate dark halo component
• Density Distribution and Shape of Galactic Dark Halo Can be Determined by Low Frequency Gravitational Waves ?
• Unveiling the Influence of Dark Matter in Axially Symmetric Galaxies
• Determining the nature of orbits in disk galaxies with non spherical nuclei
• Dark halos acting as chaos controllers in asymmetric triaxial galaxy models

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• First measurement of the triaxiality of the inner dark matter halo of the Milky Way
• Order and chaos in a three dimensional galaxy model
• Orbit properties of massive prolate galaxies in the Illustris simulation
• Orbit classification of low and high angular momentum stars
• The dynamical lineage of ultra-diffuse galaxies from TNG50-1
• Stellar Dynamical Modeling -- Counting Conserved Quantities
• How does the mass transport in disk galaxy models influence the character of orbits?
• Orbital dynamics in realistic galaxy models: NGC 3726, NGC 3877 and NGC 4010