Related papers: The Stability of Disks in Cusped Potentials
Following an approach initially outlined by McKee & Holliman, we investigate the structure and stability of dense, starless molecular cloud cores. We model those as spherical clouds in hydrostatic equilibrium and supported against gravity…
We present an extensive parameter survey to study the influence of halo mass profiles on the development of tidal tails in interacting disk galaxies. We model the galaxies using a fixed exponential disk with a central bulge and vary the…
A halo model is presented which possesses a constant phase space density (Q) core followed by a radial CDM-like power law decrease in Q. The motivation for the core is the allowance for a possible primordial phase space density limit such…
We present results of numerical modeling made for the galactic stellar and stellar-gas disk embedded in the spherical halo and bulge. The stellar disk is simulated by N-body system, the equations of hydrodynamics are solved by TVD-method.…
M. Kruskal showed that each nearly-periodic dynamical system admits a formal $U(1)$ symmetry, generated by the so-called roto-rate. We prove that such systems also admit nearly-invariant manifolds of each order, near which rapid…
The jamming of bi-disperse soft core disks is considered, using a variety of different protocols to produce the jammed state. In agreement with other works, we find that cooling and compression can lead to a broad range of jamming packing…
We derive the density profile for collisionless dissipationless dark matter haloes in hierarchical cosmologies making use of the Secondary Infall (SI) model. The novelties are: i) we deal with triaxial virialised objects; ii) their seeds in…
We construct self-consistent dynamical models for disk galaxies with triaxial, cuspy halos. We begin with an equilibrium, axisymmetric, disk-bulge-halo system and apply an artificial acceleration to the halo particles. By design, this…
We study the stability of stellar dynamical equilibrium models for M32. Kinematic observations show that M32 has a central black hole of 3x10^6 solar masses, and a phase-space distribution function that is close to the `two-integral' form…
We speculate that the dark halos of dwarf galaxies and low surface brightness galaxies soften their central cusps by the decay of a fraction of cold dark matter (CDM) particles to a stable particle with a recoiling velocity of a few tens km…
To find out whether toroidal field can stably exist in galaxies the current-driven instability of toroidal magnetic fields is considered under the influence of an axial magnetic field component and under the influence of both rigid and…
We report idealized simulations that mimic the growth of galaxy disks embedded in responsive halos and bulges. The disks manifested an almost overwhelming tendency to form strong bars that we found very difficult to prevent. We found that…
Simulations predict that the dark matter halos of galaxies should have central cusps, while those inferred from observed galaxies do not have cusps. We demonstrate, using both linear perturbation theory and n-body simulations, that a disk…
Disk-halo decompositions of galaxy rotation curves are generally performed in a parametric way. We construct self-consistent models of nonspherical isothermal halos embedding a zero-thickness disk, by assuming that the halo distribution…
We discuss the morphology, photometry and kinematics of the bars which have formed in three N-body simulations. These have initially the same disc and the same halo-to-disc mass ratio, but their haloes have very different central…
Crystalline bilayers of charged colloidal suspensions which are confined between two parallel plates and sheared via a relative motion of the two plates are studied by extensive Brownian dynamics computer simulations. The charge-stabilized…
We use 3D MHD simulations to investigate nonlinear development of the Parker, magneto-Jeans (MJI), and swing mechanisms in galactic disks. The model disks are local, isothermal, and begin from a vertically-stratified equilibrium. We first…
Dust at the midplane of a circumstellar disk can become gravitationally unstable and fragment into planetesimals if the local dust-to-gas density ratio mu is sufficiently high. We simulate how dust settles in passive disks and ask how high…
We present the simplest model that permits a largely analytical exploration of the m=1 counter-rotating instability in a "hot" nearly Keplerian disc of collisionless self-gravitating matter. The model consists of a two-component softened…
Scale-free disks have no preferred length or time scale. The question has been raised whether such disks have a continuum of unstable linear modes or perhaps no unstable modes at all. We resolve this paradox by analysing the particular case…