Time-Frequency Analysis of Asymmetric Triaxial Galaxy Model Including Effect of Spherical Dark Halo Component

Beena R. Gupta¹, Vinay Kumar^2*

¹Department of Mathematics, Lakshmibai College, University of Delhi, New Delhi, India.
²Department of Mathematics, Zakir Husain Delhi College, University of Delhi, New Delhi, India.

DOI: 10.4236/ijaa.2015.52014                

Abstract

A method of time-frequency analysis (TFA) based on wavelets is applied to study the phase space structure of three-dimensional asymmetric triaxial galaxy enclosed by spherical dark halo component. The investigation is carried out in the presence and absence of dark halo component. Time-frequency analysis is based on the extraction of instantaneous frequency from the phase of the continuous wavelet transform. This method is comparatively fast and reliable. This method can differentiate periodic from quasi-periodic, chaotic sticky from chaotic non-sticky, ordered from chaotic and also, it can accurately determine the time interval of the resonance trapping and transitions too. Apart from that, the phenomenon of transient chaos can be explained with the help of time-frequency analysis. Comparison with the method of total angular momentum (denoted as L_tot) proposed recently is also presented.

Keywords

Time-Frequency Analysis, Triaxial Galactic Potential, Instantaneous Frequency, Total Angular Momentum

Conflicts of Interest

The authors declare no conflicts of interest.

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