相关论文: Dissecting the Phase Space Snail Shell

Recent experiments by Sato et al. [1] have explored the dynamics of $^4$He superflow through an array of nanopores. These experiments have found that, as the temperature is lowered, phase-slippage in the pores changes its character, from…

The solar chromosphere contains thin, highly dynamic strands of plasma known as spicules. Recently, it has been suggested that the smallest and fastest (Type II) spicules are identical to intermittent jets observed by the Interface Region…

HERSCHEL-HIFI observations of water from the intermediate mass protostar NGC7129 FIRS 2 provide a powerful diagnostic of the physical conditions in this star formation environment. Six spectral settings, covering four H216O and two H218O…

We develop a novel method to simultaneously determine the vertical potential, force and stellar $z-v_z$ phase space distribution function (DF) in our local patch of the Galaxy. We assume that the Solar Neighborhood can be treated as a…

Nominal two-dimensional (2D) shear layers have been studied extensively, and their principal dynamics are well understood. In practical configurations, however, the behavior of such shear layers is affected by proximal surfaces. In this…

During most stages of stellar evolution the nuclear burning of lighter to heavier elements results in a radial composition profile which is stabilizing against buoyant acceleration, with light material residing above heavier material.…

We test whether the spiral patterns apparent in many large disk galaxies should be thought of as dynamical features that are stationary in a co-rotating frame for > t_{dyn}, as implied by the density wave approach for explaining spiral…

We study numerical simulations of satellite galaxy disruption in a potential resembling that of the Milky Way. Our goal is to assess whether a merger origin for the stellar halo would leave observable fossil structure in the phase-space…

We compare the distribution in position and velocity of nearby stars from the Gaia DR2 radial velocity sample with predictions of current theories for spirals in disc galaxies. Although the rich substructure in velocity space contains the…

In this work, we investigate the mixing of active scalars in two dimensions by the stirring action of stochastically generated shock waves. We use direct numerical simulations (DNS) of the interaction of shock waves with two non-reacting…

In many astrophysical environments, mixing of heavy elements occurs in the presence of a supersonic turbulent velocity field. Here we carry out the first systematic numerical study of such passive scalar mixing in isothermal supersonic…

The skyrmion crystal is a periodic array of a swirling topological spin texture. Since it is regarded as an interference pattern by multiple helical spin density waves, the texture changes with the relative phases among the constituent…

In this thesis we study the evolution of systems of concentric shells interacting gravitationally and in the process (1) propose and implement a nearly energy-conserving numerical integration scheme for evolving the concentric spherical…

As massive stars evolve, their winds change. This causes a series of hydrodynamical interactions in the surrounding medium. Whenever a fast wind follows a slow wind phase, the fast wind sweeps up the slow wind in a shell, which can be…

It has been proposed that the Hercules stream, a group of co-moving stars in the Solar neighborhood offset from the bulk of the velocity distribution, is the result of resonant interactions between stars in the outer disk and the Galactic…

We study the dynamics of faint stellar substructures around the Umbrella Galaxy, NGC 4651, which hosts a dramatic system of streams and shells formed through the tidal disruption of a nucleated dwarf elliptical galaxy. We elucidate the…

This fluid dynamics video provides sample experimental results focusing on the interactions of shear layer vortices with the trailing corner in a 2D open cavity shear layer. These interactions were investigated experimentally in a water…

One of the most intriguing spectral features of WR binary stars is the presence of time-dependent line profiles. Long term observations of several systems revealed the periodicity of this variability, synchronized with the orbital movement.…

We present VLA measurements of H92alpha radio recombination line emission from an unusual HII region G0.18--0.04, the ``Sickle'', with spatial and spectral resolutions of 27" times 24".9 and 14 km/s, respectively. These observations…

Several deep observations such as those carried out at the Canada-France-Hawaii Telescope (CFHT) have revealed prominent Low Surface Brightness (LSB) fine structures that change the apparent morphology of galaxies. Previous photometry…