Triaxiality Inhibitors in N-Body Simulations

Abstract

Numerous previous studies have investigated the phenomenon wherein initially spherical N-body systems are distorted to triaxial shapes. We report on an investigation of a previously described orbital instability that should oppose triaxiality. After verifying the instability with numerical orbit integrations that extend the original analysis, we search for evidence of the instability in N-body systems that become triaxial. Our results highlight the difficulty in separating dynamical process from finite-N effects. While we argue that our analysis points to the presence of the instability in simulated triaxial systems, discreteness appears to play a role in mimicking the instability. This suggests that predicting the shapes of real-world systems, such as dark matter halos around galaxies, based on such simulations involves more uncertainty than previously thought.

arXiv commentaccepted for publication in The Astrophysical Journal

References in corpus (13)

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• The cosmological simulation code GADGET-2
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Cited by in corpus (2)

• Predictions of the WFIRST Microlensing Survey I: Bound Planet Detection Rates
• KMT-2018-BLG-1292: A Super-Jovian Microlens Planet in the Galactic Plane