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arXiv · 1310.7920

Creation of Peanut-Shaped Bulges via the Slow Mode of Bar Growth

Michael S. Petersen·Martin D. Weinberg·Neal Katz
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Abstract

Recent theoretical work has implicated fast bar formation modes and subsequent evolution as the creation mechanism for the observed peanut-shaped bulges in some edge-on disk galaxies. We demonstrate an N-body simulation of a disk undergoing a contrasting slow mode of bar growth, unsubjected to a buckling instability, which nonetheless grows the 4:1 orbit family responsible for a peanut-shaped bulge. We also present a simulation with fast mode bar growth, which exhibits thickening similar to other work. A novel orbit classification method that finds dynamically distinct families is presented, allowing for a detailed analysis of angular momentum transfer channels within the disk.

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Michael S. Petersen, Martin D. Weinberg, Neal Katz. 2013-10-29. Creation of Peanut-Shaped Bulges via the Slow Mode of Bar Growth. https://arxiv.org/abs/1310.7920

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