相关论文: Bubble-Wrap for Bullets: The Stability Imparted By…

Key features of the mechanical response of amorphous particulate materials, such as foams, emulsions, and granular media, to applied stress are determined by the frequency and size of particle rearrangements that occur as the system…

We describe a series of experiments and computer simulations on vibrated granular media in a geometry chosen to eliminate gravitationally induced settling. The system consists of a collection of identical spherical particles on a horizontal…

Unopposed radiative cooling in clusters of galaxies results in excessive mass deposition rates. However, the cool cores of galaxy clusters are continuously heated by thermal conduction and turbulent heat diffusion due to minor mergers or…

Accretion disks are likely threaded by external vertical magnetic flux, which enhances the level of turbulence via the magnetorotational instability (MRI). Using shearing-box simulations, we find that such external magnetic flux also…

Previous studies have shown that the radiation emitted by a rapidly rotating magnetar embedded in a young supernova can greatly amplify its luminosity. These one-dimensional studies have also revealed the existence of an instability arising…

The thin-shell instability has been named as one process, which can generate entangled structures in astrophysical plasma on collisional (fluid) scales. It is driven by a spatially varying imbalance between the ram pressure of the inflowing…

The interaction between settling of dust grains and magnetorotational instability (MRI) turbulence in protoplanetary disks is analyzed. We use a reduced system of coupled ordinary differential equations to represent the interaction between…

Most cool core clusters of galaxies possess active galactic nuclei (AGN) in their centers. These AGN inflate buoyant bubbles containing non-thermal radio emitting particles. If such bubbles efficiently confine cosmic rays (CR) then this…

In the standard picture of isolated star formation, dense ``starless'' cores are formed out of magnetic molecular clouds due to ambipolar diffusion. Under the simplest spherical geometry, I demonstrate that ``starless'' cores formed this…

We study the process of magnetic reversals in the presence of a stably-stratified layer below the core-mantle boundary using direct numerical simulations of the incompressible magnetohydrodynamics equations under the Boussinesq…

This paper considers gravitational perturbations in geometrically thin disks with rotation curves dominated by a central object, but with substantial contributions from magnetic pressure and tension. The treatment is general, but the…

We consider the three-dimensional instability of a layer of horizontal magnetic field in a polytropic atmosphere where, contrary to previous studies, the field lines in the initial state are not unidirectional. We show that if the twist is…

Magnetorotational instability (MRI) in a convectively-stable layer around the neutrinosphere is simulated by a three-dimensional model of supernova core. To resolve MRI-unstable modes, a thin layer approximation considering only the radial…

We examine the linear stability of an isothermal filamentary cloud permeated by a perpendicular magnetic field. Our model cloud is assumed to be supported by gas pressure against the self-gravity in the unperturbed state. For simplicity,…

Cold fronts (CFs) - density and temperature plasma discontinuities - are ubiquitous in cool cores of galaxy clusters, where they appear as X-ray brightness edges in the intracluster medium, nearly concentric with the cluster center. We…

How does turbulence contribute to the formation and structure of the dense interstellar medium (ISM)? Molecular clouds are dense, high-pressure objects. It is usually argued that gravitational confinement causes the high pressures, and that…

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 report the detection of a curved magnetic field in the ring-like shell of the bubble N4, derived from near-infrared polarization of reddened diskless stars located behind this bubble. The magnetic field in the shell is curved and…

Macroscopic gas motions are widespread throughout the solar atmosphere and shearing motions couple to the non--ideal effects, destabilising low frequency fluctuations in the medium. The origin of this non-ideal magnetohydrodynamic…

In giant molecular clouds (GMCs), shocks driven by converging turbulent flows create high-density, strongly-magnetized regions that are locally sheetlike. In previous work, we showed that within these layers, dense filaments and embedded…