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Related papers: Galactic disks as reaction-diffusion systems

200 papers

The timescale for star formation, a measure of how quickly neutral gas is being converted to stars, is considerably longer than typical dynamical timescales associated with a galactic disk. For purposes of modeling galaxy evolution,…

Astrophysics of Galaxies · Physics 2014-11-20 Tony Wong

Galaxies are built by complex physical processes with significant inherent stochasticity. It is therefore surprising that the inferred dark matter distributions in galaxies are strongly correlated with the observed baryon distributions…

Astrophysics of Galaxies · Physics 2021-01-06 Shankar C. Venkataramani , Alan C. Newell

Using hydrodynamic approach, it is shown that the properties of a marginally stable collisionless stellar disc resemble those of a thermodynamic system undergoing a gas--liquid phase transition. The maximum in Toomre's stability diagram,…

Astrophysics of Galaxies · Physics 2010-01-04 E. I. Ivannikova , M. N. Maksumov

Adopting a single-zone framework, with accretion of primordial gas on a free-fall timescale, the chemical evolution of the Galactic bulge is calculated, assuming (i) a corresponding rapid timescale for star formation, and (ii) an initial…

Galactic spiral shocks are dominant morphological features and believed to be responsible for substructure formation within spiral arms in disk galaxies. They can also contribute a substantial amount of kinetic energy to the interstellar…

Astrophysics of Galaxies · Physics 2015-05-19 Chang-Goo Kim , Woong-Tae Kim , Eve C. Ostriker

The exponential profile has long been hypothesized as the fundamental morphology of galactic disks. The IllustrisTNG simulations reproduce diverse surface-density profiles: Type I (single exponential), Type II (down-bending), and Type III…

Astrophysics of Galaxies · Physics 2026-04-30 Liufei Chen , Min Du , Shuai Lu , Jing Li , Luis C. Ho

We investigate the evolution of galactic disks in N-body Tree-SPH simulations. We find that disks, initially truncated at three scale-lengths, can triple their radial extent, solely driven by secular evolution. Both Type I (single…

Astrophysics of Galaxies · Physics 2015-06-04 I. Minchev , B. Famaey , A. C. Quillen , P. Di Matteo , F. Combes , M. Vlajic , P. Erwin , J. Bland-Hawthorn

Interstellar turbulence is driven over a wide range of scales by processes including spiral arm instabilities and supernovae, and it affects the rate and morphology of star formation, energy dissipation, and angular momentum transfer in…

Astrophysics · Physics 2016-01-27 Bruce G. Elmegreen

Counterrotating stars in disk galaxies are a puzzling dynamical feature whose origin has been ascribed to either satellite accretion events or to disk instabilities triggered by deviations from axisymmetry. We use a cosmological simulation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 David G. Algorry , Julio F. Navarro , Mario G. Abadi , Laura V. Sales , Matthias Steinmetz , Franziska Piontek

Evolution of galaxies is one of the most actual topics in astrophysics. Among the most important factors determining the evolution are two galactic components which are difficult or even impossible to detect optically: the gaseous disks and…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-14 R. Kipper , E. Tempel , A. Tamm

We present an end-to-end description of the formation process of globular clusters (GCs) which combines a treatment for their formation and dynamical evolution within galaxy haloes with a state-of-the-art semi-analytic simulation of galaxy…

We present first results concerning the metallicities and stellar populations of galaxies formed in a cosmologically motivated simulation. The calculations include dark matter, gas dynamics, radiation processes, star formation, supernovae…

Astrophysics · Physics 2007-05-23 Matthias Steinmetz , Ewald Mueller

We use a high-resolution grid-based hydrodynamics method to simulate the multi-phase interstellar medium in a Milky Way-size quiescent disk galaxy. The models are global and three-dimensional, and include a treatment of star formation and…

Astrophysics · Physics 2009-11-13 Elizabeth J. Tasker , Greg L. Bryan

Symmetry-breaking instabilities play an important role in understanding the mechanisms underlying the diversity of patterns observed in nature, such as in Turing's reaction--diffusion theory, which connects cellular signalling and transport…

Pattern Formation and Solitons · Physics 2023-12-25 Andrew L. Krause , Eamonn A. Gaffney , Thomas Jun Jewell , Václav Klika , Benjamin J. Walker

Large scale vortices could play a key role in the evolution of protoplanetary disks, particularly in the dead-zone where no turbulence associated with magnetic field is expected. Their possible formation by the subcritical baroclinic…

Earth and Planetary Astrophysics · Physics 2016-08-17 P. Barge , S. Richard , S. Le Dizes

The Galactic center stellar disk and the circumnuclear ring provide a unique opportunity to study in detail the dynamics and physical conditions of distant molecular disks in the nuclei of galaxies. One of the key questions is how these…

Astrophysics of Galaxies · Physics 2015-06-03 F. Yusef-Zadeh , M. Wardle

We characterize the radial migration of stars in the disk plane by calculating the diffusion coefficient and the diffusion time-scale for a bulge-disk N-body self-consistent system with a marginally-stable Toomre-Q parameter. We find that…

Astrophysics of Galaxies · Physics 2012-09-21 Maura Brunetti , Cristina Chiappini , Daniel Pfenniger

Dynamos in astrophysical disks are usually explained in terms of the standard alpha-omega mean field dynamo model where the local helicity generates a radial field component from an azimuthal field. The subsequent shearing of the radial…

Astrophysics · Physics 2015-06-24 Ethan T. Vishniac

Stellar scattering off of orbiting or transient clumps is shown to lead to the formation of exponential profiles in both surface density and velocity dispersion in a two-dimensional non-self gravitating stellar disk with a fixed halo…

Astrophysics of Galaxies · Physics 2015-06-17 Bruce G. Elmegreen , Curtis Struck

Rogue waves are an intriguing nonlinear phenomenon arising across different scales, ranging from ocean waves through optics to Bose-Einstein condensates. We describe the emergence of rogue-like wave dynamics in a reaction-diffusion system…

Pattern Formation and Solitons · Physics 2024-05-27 Edgar Knobloch , Arik Yochelis