arXiv subjects

T. Manos

Publications and source records attributed to T. Manos.

22 records · Page 2Linked to original sources

arXiv2007

Studying the global dynamics of conservative dynamical systems using the SALI chaos detection method

We use the Smaller ALignment Index (SALI) method of chaos detection, to study the global dynamics of conservative dynamical systems described by differential or difference equations. In particular, we consider the well--known 2 and 4--dimensional symplectic standard map, as well as an autonomous Hamiltonian system of 2 and 3 degrees of freedom describing the motion of a star in models of barred galaxies. The application of SALI helped us to compute rapidly and accurately the percentage of regular and chaotic motion for particular values of the parameters of these systems. We were also able to perform a computationally efficient determination of the dependence of these percentages on the variation of several parameters of the studied models.

nlin.CD↗

arXiv2006

Barred Galaxies:Studying the chaotic and ordered nature of orbits

The chaotic or ordered character of orbits in galactic models is an important issue, since it can influence dynamical evolution. This distinction can be achieved with the help of the Smaller Alingment Index - (SALI). We describe here briefly this method and its advantages. Then we apply it to that case of 2D and 3D barred galaxy potentials. In particular, we find the fraction of chaotic and ordered orbits in such potentials and present how this fraction changes when the main parameters of the model are varied. For this, we consider models with different bar mass, bar thickness or pattern speed. Varying only one parameter at a time, we find that bars that are more massive, or thinner, or faster, have a larger fraction of chaotic orbits.

astro-ph↗

arXiv2005

Chaos and the dynamical evolution of barred galaxies

The dynamical evolution of barred galaxies depends crucially on the fraction and their spacial distribution of chaotic orbits in them. In order to distinguish between the two kinds of orbits, we use the Smaller Alignment Index (SALI) method, a very powerful method which can be applied to problems of galactic dynamics. Using model potentials, and taking into account the full 3D distribution of matter, we discuss how the distribution of chaotic orbits depends on the main model parameters, like the mass of the various components and the bar axial ratio.

astro-ph↗

arXiv2005

Detecting chaotic and ordered motion in barred galaxies

A very important issue in the area of galactic dynamics is the detection of chaotic and ordered motion inside galaxies. In order to achieve this target, we use the Smaller ALignment Index (SALI) method, which is a very suitable tool for this kind of problems. Here, we apply this index to 3D barred galaxy potentials and we present some results on the chaotic behavior of the model when its main parameters vary.

astro-ph↗