相关论文: On the Vega Debris Disc's Dust Grains: Short-Lived…
It has been argued that the photometric data and images of the archetypical debris disk around Vega may be in contradiction with the standard, steady-state collisional scenario of the disk evolution. Here we perform physical modeling of the…
This study employed grain dynamic models to examine the density distribution of debris discs, and discussed the effects of the collisional time-intervals of asteroidal bodies, the maximum grain sizes, and the chemical compositions of the…
The vertical thickness of debris discs is often used as a measure of these systems' dynamical excitation and as clues to the presence of hidden massive perturbers such as planetary embryos. However, this argument could be flawed because the…
We present high spatial resolution mid- and far-infrared images of the Vega debris disk obtained with the Multiband Imaging Photometer for Spitzer (MIPS). The disk is well resolved and its angular size is much larger than found previously.…
We have used the velocity dispersion as an age indicator to constrain the ages of a large sample of main sequence Vega-like stars in order to study the lifetimes and temporal evolution of the dust disks around them. We use HIPPARCOS…
The cross section of material in debris discs is thought to be dominated by the smallest grains that can still stay in bound orbits despite the repelling action of stellar radiation pressure. Thus the minimum (and typical) grain size…
Context. Binary systems can be born surrounded by circumbinary discs. The gaseous discs surrounding either of the two stellar companions can have their life extended by the supply of mass arriving from the circumbinary disc. Aims. The…
Millimeter interferometry provides evidence for the presence of mm to cm size "pebbles" in the outer parts of disks around pre-main-sequence stars. The observations suggest that large grains are produced relatively early in disk evolution…
We present new sub-mm observations and modelling of Vega excess stars, using realistic dust grain models. For resolved disks, we find that different objects require very different dust grain properties in order to simultaneously fit the…
Many asteroids show indications they have undergone impacts with meteoroid particles having radii between 0.01 m and 1 m. During such impacts, small dust grains will be ejected at the impact site. The possibility of these dust grains (with…
Millimeter emitting dust grains have sizes that make them susceptible to drift in protoplanetary disks due to a difference between their orbital speed and that of the gas. The characteristic drift timescale depends on the surface density of…
Previous studies have found that Vega is surrounded by an extended debris disc that is very smooth in the far infrared, but displays possible clumpiness at 850micron and dust emission peaks at 1.3mm. We reobserved Vega at 1.3mm with PdBI to…
The timescales on which astronomical dust grows remain poorly understood, with important consequences for our understanding of processes like circumstellar disk evolution and planet formation.A number of post-asymptotic giant branch stars…
Debris disks are dusty, gas-poor disks around main sequence stars (Backman & Paresce 1993; Lagrange, Backman & Artymowicz 2000; Zuckerman 2001). Micron-sized dust grains are inferred to exist in these systems from measurements of their…
Clumpy structure in the debris disk around Vega has been previously reported at millimeter wavelengths and attributed to concentrations of dust grains trapped in resonances with an unseen planet. However, recent imaging at similar…
The settling of dust particles plays a critical role in the growth and dynamics of dust grains. We performed a detailed modeling of the ALMA continuum substructures for six highly inclined protoplanetary discs using radiative transfer…
In this paper we analyze new observations from ALMA and VLA, at a high angular resolution corresponding to 5 - 8 au, of the protoplanetary disk around HD 163296 to determine the dust spatial distribution and grain properties. We fit the…
This paper considers the distribution of dust which originates in the break-up of planetesimals that are trapped in resonance with a planet. There are three grain populations with different spatial distributions: (I) large grains have the…
Transitional discs have central regions characterised by significant depletion of both dust and gas compared to younger, optically-thick discs. However, gas and dust are not depleted by equal amounts: gas surface densities are typically…
Observations of debris disks offer a window into the physical and dynamical properties of planetesimals in extrasolar systems through the size distribution of dust grains. In particular, the millimeter spectral index of thermal dust…