2018/03/05 by Eric I. Barnes, Evan Dowling
Engineering · Physics and Astronomy · #Aerospace engineering #Astrophysics #Classical mechanics #Engineering #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Instability #Mechanics #Orbit (dynamics) #Physics #Scientific Research and Discoveries #Statistical physics #Stellar, planetary, and galactic studies #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/aab4a0
accepted for publication in The Astrophysical Journal
arxiv created 2018/03/05 · openalex created_date 2018/03/29 · openalex publication_date 2018/04/06 · arxiv updated 2018/04/25 · openalex updated_date 2026/08/06
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 of 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.