相关论文: Shear-gravity transition determines the steep velo…
The dispersion of a passive scalar in a fluid through the combined action of advection and molecular diffusion is often described as a diffusive process, with an effective diffusivity that is enhanced compared to the molecular value.…
The bulk flow velocity for the cluster of interstellar cloudlets within about 30 pc of the Sun is determined from optical and ultraviolet absorption line data, after omitting from the sample stars with circumstellar disks or variable…
The evolution of micron-sized droplets in clouds is studied with focus on the 'size-gap' regime of 15-40 $\mu m$ radius, where condensation and differential sedimentation are least effective in promoting growth. This bottleneck leads to…
We numerically investigate the self-diffusion coefficient and correlation length of the rigid clusters (i.e., the typical size of the collective motions) in sheared soft athermal particles. Here we find that the rheological flow curves on…
Semi-analytical models of galaxy formation can be used to predict the evolution of the number density of early-type galaxies as a function of the circular velocity at the virial radius, v_{c,vir}. Gravitational lensing probability and…
We present the $0.6<z<2.6$ evolution of the ionized gas velocity dispersion in 175 star-forming disk galaxies based on data from the full KMOS$^{\rm 3D}$ integral field spectroscopic survey. In a forward-modelling Bayesian framework…
Most studies of correlations between X-ray and optical properties of galaxy clusters have used the largest samples of data available, regardless of the morphological types of clusters included. Given the increasing evidence that morphology…
We study the intrinsic nature of the finite system-size effect in estimating shear viscosity of dilute and dense fluids within the framework of the Green-Kubo approach. From extensive molecular dynamics simulations, we observe that the size…
Turbulence plays a major role in the formation and evolution of molecular clouds. The problem is that turbulent velocities are convolved with the density of an observed region. To correct for this convolution, we investigate the relation…
We investigate the behavior of the shear viscosity $\eta(p)$ and the mass-dependent diffusion coefficient $D(m,p)$ in the context of a simple model that, as the crosslink density $p$ is increased, undergoes a continuous transition from a…
We investigate the rheology of a sheared granular gas composed of hard spheres with a velocity-dependent restitution coefficient. Using kinetic theory, we derive the shear viscosity and show that it exhibits an S-shaped dependence on the…
Current understanding of the secular evolution of galactic disks suggests that this process is dominated by two or more heating mechanisms, which increase the random motions of stars in the disk. In particular, the gravitational influence…
Granular materials react to shear stresses differently than do ordinary fluids. Rather than deforming uniformly, materials such as dry sand or cohesionless powders develop shear bands: narrow zones containing large relative particle motion…
This paper presents a possible way to understand dissolution of OB associations (or groups). Assuming rapid escape of parental cloud gas from associations, we show that the shadow of the formation environment for associations can be…
Turbulence is a complex phenomenon that plays a critical role in the interstellar medium (ISM). Previous simulations and observations show that the probability density function (PDF) of gas density in isothermal and compressible systems…
Using Grad's method, we calculate the entropy production and derive a formula for the second-order shear viscosity coefficient in a one-dimensionally expanding particle system, which can also be considered out of chemical equilibrium. For a…
We present a comparison of the observed, spatially integrated stellar and ionized gas velocity dispersions of $\sim1000$ massive ($\log M_{\star}/M_{\odot}\gtrsim\,10.3$) galaxies in the Large Early Galaxy Astrophysics Census (LEGA-C)…
We use the infrared excess (IRX) FIR/UV luminosity ratio to study the relation between the effective UV attenuation (A_IRX) and the UV spectral slope (beta) in a sample of 450 1<z<2.5 galaxies. The FIR data is from very deep Herschel…
We study shear stress relaxation for a gelling melt of randomly crosslinked, interacting monomers. We derive a lower bound for the static shear viscosity $\eta$, which implies that it diverges algebraically with a critical exponent $k\ge…
We developed a Bayesian framework to determine in a robust way the relation between velocity dispersions and chemical abundances in a sample of stars. Our modelling takes into account the uncertainties in the chemical and kinematic…