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Chaos or Order in Double Barred Galaxies?

Witold Maciejewski
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Abstract

Bars in galaxies are mainly supported by particles trapped around closed periodic orbits. These orbits respond to the bar's forcing frequency only and lack free oscillations. We show that a similar situation takes place in double bars: particles get trapped around orbits which only respond to the forcing from the two bars and lack free oscillations. We find that writing the successive positions of a particle on such an orbit every time the bars align generates a closed curve, which we call a loop. Loops allow us to verify consistency of the potential. As maps of doubly periodic orbits, loops can be used to search the phase-space in double bars in order to determine the fraction occupied by ordered motions.

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Witold Maciejewski. 2003-04-24. Chaos or Order in Double Barred Galaxies?. https://doi.org/10.1007/978-3-540-45040-5_6

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