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

Beena R.  Gupta; Vinay  Kumar

doi:10.4236/ijaa.2015.52014

Beena R. Gupta¹, Vinay Kumar²^*

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 Ltot) proposed recently is also presented.

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

Cite this paper: Gupta, B. and Kumar, V. (2015) Time-Frequency Analysis of Asymmetric Triaxial Galaxy Model Including Effect of Spherical Dark Halo Component. International Journal of Astronomy and Astrophysics, 5, 106-115. doi: 10.4236/ijaa.2015.52014.

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