2017/07/27 by F. Combes, Combes, F.
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena
paper · pdf · doi:10.48550/arxiv.1707.08733
openalex publication_date 2017/07/27 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The internal evolution of disk galaxies like the Milky Way are driven by non-axisymmetries (bars) and the implied angular momentum transfer of the matter; baryons are essentially driven inwards to build a more concentrated disk. This mass concentration may lead to the decoupling of a secondary bar, since the orbit precessing frequency is then much enhanced. Vertical resonances with the bar will form a box/peanut bulge in a Gyr time-scale. Gas flows due to gravity torques can lead to a young nuclear disk forming stars, revealed by a sigma-drop in velocity dispersion. These gas flows moderated by feedback produce intermittent accretion of the super-massive black hole, and cycles of AGN activity. The fountain effect due to nuclear star formation may lead to inclined, and even polar nuclear disks.