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Related papers: Introducing a new 3D dynamical model for barred ga…

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A 3D steady state stellar dynamical model for the Galactic bar is constructed with 485 orbit building blocks using an extension of Schwarzschild technique. The weights of the orbits are assigned using non-negative least square method. The…

Astrophysics · Physics 2015-06-24 HongSheng Zhao

A multi-faceted approach is described to constrain the importance of bar-driven evolution in disk galaxies, particularly bulge formation. N-body simulations are used to construct stellar kinematic bar diagnostics for edge-on systems and to…

Astrophysics · Physics 2016-01-27 M. Bureau , E. Athanassoula , A. Chung , G. Aronica

We use Laskar's frequency mapping technique to study the dynamics of triaxial galaxies with central density cusps and nuclear black holes. For ensembles of 10^4 orbits, we numerically compute the three fundamental frequencies of the motion,…

Astrophysics · Physics 2009-10-30 Monica Valluri , David Merritt

We study the dynamics near the unstable Lagrangian points in galactic bar models using dynamical system tools in order to determine the global morphology of a barred galaxy. We aim at the case of non-autonomous models, in particular with…

Astrophysics of Galaxies · Physics 2018-10-17 Patricia Sanchez-Martin , Josep. J. Masdemont , Merce Romero-Gomez

Most galaxies have a warped shape when they are seen from an edge-on point of view. The reason for this curious form is not completely known so far and in this work we apply dynamical system tools to contribute to its explanation. Starting…

Astrophysics of Galaxies · Physics 2016-03-23 Patricia Sanchez-Martin , Merce Romero-Gomez , Josep J. Masdemont

Barred structures are important in understanding galaxy evolution, but they were not included explicitly in most dynamical models for nearby galaxies due to their complicated morphological and kinematic properties. We modify the triaxial…

Astrophysics of Galaxies · Physics 2022-12-21 Behzad Tahmasebzadeh , Ling Zhu , Juntai Shen , Ortwin Gerhard , Glenn van de Ven

We study the behavior of orbits in two different galactic dynamical models, describing the motion in the central parts of a triaxial elliptical galaxy with a dense nucleus. Numerical experiments show that both models display regular motion…

Astrophysics of Galaxies · Physics 2015-06-04 Euaggelos E. Zotos

In four-dimensional symplectic maps complex instability of periodic orbits is possible, which cannot occur in the two-dimensional case. We investigate the transition from stable to complex unstable dynamics of a fixed point under parameter…

Chaotic Dynamics · Physics 2021-04-21 Jonas Stöber , Arnd Bäcker

We study dynamics of a ball moving in gravitational field and colliding with a moving table. The motion of the limiter is assumed as periodic with piecewise constant velocity - it is assumed that the table moves up with a constant velocity…

Chaotic Dynamics · Physics 2011-04-04 Andrzej Okninski , Boguslaw Radziszewski

Based on a high quality $N$-body simulation of a double bar galaxy model, we investigate the evolution of the bar properties, including their size, strength and instantaneous pattern speed derived by using three distinct methods: the…

Astrophysics of Galaxies · Physics 2018-07-11 Yu-Ting Wu , Daniel Pfenniger , Ronald E. Taam

We investigate a model of high-dimensional dynamical variables with all-to-all interactions that are random and non-reciprocal. We characterize its phase diagram and show that the model can exhibit chaotic dynamics. We show that the…

Disordered Systems and Neural Networks · Physics 2025-12-15 Samantha J. Fournier , Alessandro Pacco , Valentina Ros , Pierfrancesco Urbani

In this paper, two models of interest for Celestial Mechanics are presented and analysed, using both analytic and numerical techniques, from the point of view of the possible presence of regular and/or chaotic motion, as well as the…

Earth and Planetary Astrophysics · Physics 2024-02-02 Irene De Blasi

The gas dynamics in the Galactic disc is modeled by releasing an initially axisymmetric SPH component in a completely self-consistent and symmetry-free 3D N-body simulation of the Milky Way in which the stellar components display a…

Astrophysics · Physics 2007-05-23 R. Fux

Dissipationless N-body models of rotating galaxies, iso-energetic to a non-rotating model, are examined as regards the mass in regular and in chaotic motion. The values of their spin parameters $\lambda$ are near the value $\lambda=0.22$ of…

Astrophysics · Physics 2009-09-29 N. Voglis , I. Stavropoulos , C. Kalapotharakos

This paper presents a new approach to studying galactic structures. They are considered as the low-frequency normal modes in a disc of orbits precessing at different angular speeds. Such a concept is an adequate alternative to the commonly…

Astrophysics · Physics 2009-11-10 E. V. Polyachenko

We study the role of asymptotic curves in supporting the spiral structure of a N-body model simulating a barred spiral galaxy. Chaotic orbits with initial conditions on the unstable asymptotic curves of the main unstable periodic orbits…

Astrophysics of Galaxies · Physics 2011-08-31 George Contopoulos , Mirella Harsoula

In a series of papers we study the stellar dynamics of the grand design barred-spiral galaxy NGC~1300. In the first paper of this series we estimate the gravitational potential and we give it in a form suitable to be used in dynamical…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 C. Kalapotharakos , P. A. Patsis , P. Grosbol

We built three models for the gravitational field of the Galactic bar. These models are an inhomogeneous ellipsoid, an inhomogeneous prolate spheroid, and a superposition of four inhomogeneous ellipsoids. Among the three models, the…

Astrophysics · Physics 2009-11-10 Barbara Pichardo , Marco Martos , Edmundo Moreno

We present the orbital analysis of four response models, that succeed in reproducing morphological features of NGC 1300. Two of them assume a planar (2D) geometry with $\Omega_p$=22 and 16 \ksk respectively. The two others assume a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 P. A. Patsis , C. Kalapotharakos , P. Grosbol

Like the majority of spiral galaxies, the Milky Way contains a central non-axisymmetric bar component. Our position in the Galactic plane renders it rather hard to see, but also allows us to make measurements of the bar that are completely…

Astrophysics · Physics 2008-11-26 M. R. Merrifield