2004/01/01 by Andreas Burkert, Andreas M. Burkert, Elena D'Onghia +1 · 19 citations
Physics and Astronomy · #Angular momentum #Angular momentum coupling #Astronomy and Astrophysical Research #Dark matter #Electrical and Electromagnetic Research #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Protogalaxy #Specific relative angular momentum #Star formation #Total angular momentum quantum number #astro-ph
paper · pdf · doi:10.1007/978-1-4020-2862-5_32
published in Astrophysics and space science library, 341-358 (Springer Nature (Netherlands)) · 16 pages, 7 postscript files, requires kapproc.cls and procps.sty; to appear in "Penetrating Bars Through Masks of Cosmic Dust: The Hubble Tuning Fork Strikes a New Note", ed. Block, Freeman, Puerari and Groess, Dordrecht: Kluwer
openalex publication_date 2004/01/01 · arxiv created 2004/09/22 · arxiv updated 2016/01/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The importance of angular momentum in regulating the sizes of galactic disks and by this their star formation history is highlighted. Tidal torques and accretion of satellites in principle provide enough angular momentum to form disks with sizes that are in agreement with observations. However three major problems have been identified that challenge cold dark matter theory and affect models of galaxy evolution: (1) too much angular momentum is transferred from the gas to the dark halos during infall, leading to disks with scale lengths that are too small, (2) bulgeless disks require more specific angular momentum than is generated cosmologically even if gas would not lose angular momentum during infall, (3) gravitational torques and hierarchical merging produce a specific angular momentum distribution that does not match the distribution required to form exponential disks naturally; some gas has exceptionally high angular momentum, leading to extended outer disks while another large gas fraction will contain very little specific angular momentum and is expected to fall into the galactic center, forming a massive and dominant bulge component. Any self-consistent theory of galaxy formation will require to provide solutions to these questions. Selective mass loss of low-angular-momentum gas in an early phase of galaxy evolution currently seems to be the most promising scenario. Such a process would have a strong affect on the early protogalactic evolution phase, the origin and evolution of galactic morphologies and link central properties of galaxies like the origin of central massive black holes with their global structure.