2018/01/31 by Hagai B. Perets, A. Mastrobuono-Battisti, Perets, Hagai B. +6
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics and Star Formation Studies #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #astro-ph.GA
paper · pdf · doi:10.48550/arxiv.1802.00012
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arxiv created 2018/01/31 · openalex publication_date 2018/01/31 · arxiv updated 2018/02/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The Galactic center of the Milky-Way harbors a massive black hole (BH) orbited by a diverse population of young and old stars. A significant fraction of the youngest stars (∼4-7 Myr) reside in a thin stellar disk with puzzling properties; the disk appears to be warped, shows asymmetries, and contains one or more clumpy structures (e.g. IRS 13). Models explaining the clumping invoked the existence of an intermediate-mass BH of 103-104 M\odot, but no kinematic evidence for such a BH has been found. Here we use extended N-body simulations and hybrid self-consistent field method models to show that naturally formed residual temporal asphericity of the hosting nuclear star cluster gives rise to torques on the disk, which lead to changes in its orientation over time, and to recurrent formation and dissolution of single spiral arm (m=1 modes) structures. The changing orientation leads to a flapping-like behavior of the disk and to the formation of a warped disk structure. The spiral arms may explain the over-densities in the disk (clumping) and its observed asymmetry, without invoking the existence of an intermediate-mass BH. The spiral arms are also important for the overall disk evolution and can be used to constrain the structure and composition of the nuclear stellar cluster.