Related papers: Secular Evolution of the Galactic Disk
Observations of disk galaxies at z~2 have demonstrated that turbulence driven by gravitational instability can dominate the energetics of the disk. We present a 1D simulation code, which we have made publicly available, that economically…
Context. Stellar migration of the galactic disc stars has been invoked to explain the dispersion of stellar metallicity observed in the solar neighborhood. Aims. We seek to identify the dynamical mechanisms underlying stellar migration in…
Disks of low-mass bodies scattered by giant planets to large semi-major axis and constant periapsis orbits are vulnerable to a buckling instability. This instability exponentially grows orbital inclinations, raises periapsis distances, and…
This chapter reviews theoretical work on the stellar dynamics of galaxy disks. All the known collective global instabilities are identified, and their mechanisms described in terms of local wave mechanics. A detailed discussion of warps and…
I review recent progress from $N$-body simulations in our understanding of the secular evolution of isolated disk galaxies. I describe some of the recent controversies in the field which have been commonly attributed to numerics. The…
Observations show that radial metallicity gradients in disk galaxies are relatively shallow, if not flat, especially at large galactocentric distances and for galaxies in the high-redshift universe. Given that star formation and metal…
Recent observations of the Galactic center revealed a nuclear disk of young OB stars near the massive black hole (MBH), in addition to many similar outlying stars with higher eccentricities and/or high inclinations relative to the disk…
The secular evolution process which slowly transforms the morphology of a given galaxy over its lifetime through mostly internal dynamical mechanisms could naturally account for most of the observed properties of physical galaxies (Zhang…
We review internal processes of secular evolution in galaxy disks, concentrating on the buildup of dense central features that look like classical, merger-built bulges but that were made slowly out of disk gas. We call these pseudobulges.…
Protoplanetary disks are mainly heated by radiation from the central star. Since the incident stellar flux at any radius is sensitive to the disk structure near that location, an unstable feedback may be present. Previous investigations…
Using available kinematical data for a subsample of NLTT stars from the HIPPARCOS mission we confirm the existence of a previously reported local anomaly in the (u,v) plane: the mean motion u for old disc stars, with v < -30 km/s, is…
We test the effect of assumptions about stellar motion on the behavior of gravitational instabilities in protoplanetary disks around solar-type stars by performing two simulations that are identical in all respects except the treatment of…
The evolution of circumstellar discs is influenced by their surroundings. The relevant processes include external photoevaporation due to nearby stars, and dynamical truncations. The impact of these processes on disc populations depends on…
We study the dynamical evolution of disk and halo globular clusters in the Milky Way using a series of Fokker-Planck calculations combined with parametric statistical models. Our sample of 113 clusters with velocity data is predicted to…
Observational and theoretical evidence that internal, slow ("secular") evolution reshapes galaxy disks is reviewed in Kormendy & Kennicutt (2004, ARAA, 42, 603). This update has three aims. First, I emphasize that this evolution is very…
The gas component plays a major role in the dynamics of spiral galaxies, because of its dissipative character, and its ability to exchange angular momentum with stars in the disk. Due to its small velocity dispersion, it triggers…
The properties and star formation processes in the far-outer disks of nearby spiral and dwarf irregular galaxies are reviewed. The origin and structure of the generally exponential profiles in stellar disks is considered to result from…
The long-term evolution of stellar orbits bound to a massive centre is studied in order to understand the cores of star clusters in central regions of galaxies. Stellar trajectories undergo tiny perturbation, the origin of which is twofold:…
The circular velocities of the inner region of disk galaxies are predicted by standard physics but velocities beyond the stellar disks are not consistent with Newtonian physics if the material there is in stable circular orbits. However,…
We investigate the dynamical evolution of galaxies in groups with different formation epochs. Galaxy groups have been selected to be in different dynamical states, namely dynamically old and dynamically young, which reflect their early and…