Inside-out Galaxy Formation

Abstract

Current theories of galaxy formation have tended to focus on hierarchical structure formation, which is the most likely scenario for cosmological models with lots of power at small scales (e.g. standard cold dark matter). Models with little small scale power lead to scenarios closer to spherical collapse. Recently favored power spectra (e.g. CDM+Lambda) lie somewhere in between suggesting that both types of processes are important and may vary over time due to gaseous reheating. From this viewpoint this paper explores a very simple inside out scenario for galaxy formation. This scenario is a natural result of synthesizing earlier work on DM halos, spherical collapse, and gas redistribution via angular momentum. Although, this model is highly simplified and is not designed to accurately describe the detailed formation of any individual galaxy, it does (by design) predict the overall features of galaxies. In addition, old bulges and young disks are an almost unavoidable result of these very simple models. This scenario may provide a useful framework for both observers and theoreticians to think about galaxy formation.

21 pages including 6 figures

References in corpus (4)

• The Star Formation History of Field Galaxies
• The Delayed Formation of Dwarf Galaxies
• Cosmological Constraints from High-Redshift Damped Lyman-Alpha Systems
• The Spectra of Star Forming Galaxies at High Redshift

Cited by in corpus (21)

• Angular momentum and galaxy formation revisited
• The Angular Momentum of Gas in Proto-Galaxies I. Implications for the Formation of Disk Galaxies
• The origin of the diverse morphologies and kinematics of Milky Way-mass galaxies in the FIRE-2 simulations
• Age Demographics of the Milky Way Disk and Bulge
• Two Growing Modes and the Morphology-Quiescence Relation in Galaxies
• Infrared spectroscopy of cataclysmic variables: III. Dwarf novae below the period gap and novalike variables
• The Impact of Dust on the Sizes of Galaxies in the Epoch of Reionization
• Stellar age gradients and inside-out star formation quenching in galaxy bulges
• Characterizing the radial oxygen abundance distribution in disk galaxies
• BUDDI-MaNGA II: The Star-Formation Histories of Bulges and Discs of S0s
• Testable predictions of outside-in age gradients in dwarf galaxies of all types
• The Structural Evolution of Isolated Galaxies at Low Redshift in the IllustrisTNG Simulation
• NGC 1436: the making of a lenticular galaxy in the Fornax cluster
• The Chemical Abundance Structure of the Inner Milky Way: A Signature of "Upside-Down" Disk Formation?
• The Loneliest Galaxies in the Universe: A GAMA and GalaxyZoo Study on Void Galaxy Morphology
• Spatially resolved properties of the grand-design spiral galaxy UGC 9837: a case for high-redshift 2D observations
• The Grism Lens-Amplified Survey from Space (GLASS). XII. Spatially Resolved Galaxy Star Formation Histories and True Evolutionary Paths at z > 1
• Isolated Galaxies versus Interacting Pairs with MaNGA
• The bimodality in the mass-metallicity relation in SDSS-MaNGA galaxy pairs
• Redshift and stellar mass dependence of intrinsic shapes of disc-dominated galaxies from COSMOS observations below $z=1.0$
• The breakBRD Breakdown: Using IllustrisTNG to Track the Quenching of an Observationally-Motivated Sample of Centrally Star-Forming Galaxies