相关论文: Composite Interstellar Grains
We have analyzed the 9.7 and ``18'' micron interstellar silicate absorption features along the line of sight toward four heavily extincted galactic WC-type Wolf-Rayet (WR) stars. We construct two interstellar extinction curves from 1.25 to…
Icy grains in the interstellar medium and star-formation regions consist of a variety of materials. Such composite grains interact differently with cosmic-ray (CR) particles compared to simple single-material grains. We aim to calculate the…
We present polarisation spectra of seven stars in the lines-of-sight towards the Sco OB1 association. Our spectra were obtained within the framework of the Large Interstellar Polarization Survey carried out with the FORS instrument of the…
Our current understanding of interstellar dust is summarized at an introductory level. Submicron-sized interstellar dust grains absorb and scatter light, and reradiate the absorbed energy in the infrared. The grain population spans a range…
We examine a synthetic way of constructing the grain size distribution in the interstellar medium (ISM). First we formulate a synthetic grain size distribution composed of three grain size distributions processed with the following…
We investigate the abundance and properties (especially, grain size) of dust in galaxy halos using available observational data in the literature. There are two major sets of data. One is (i) the reddening curves at redshifts $z\sim 1$ and…
We have studied the interstellar extinction in a field of ~3' x 3' at the core of the 30 Doradus nebula, including the central R136 cluster, in the Large Magellanic Cloud. Observations at optical and near-infrared wavelengths, obtained with…
The Two Micron All Sky Survey, along with the Stellar Population Synthesis Model of the Galaxy, developed in Besancon, is used to calculate the extinction distribution along different lines of sight. By combining many lines of sight, the…
We investigate the scattering and absorption of light by random ballistic aggregates of spherical monomers. We present a general measure for the porosity of an irregular particle. Three different classes of ballistic aggregates are…
Polarized extinction and emission from dust in the interstellar medium (ISM) are hard to interpret, as they have a complex dependence on dust optical properties, grain alignment and magnetic field orientation. This is particularly true in…
We present a new version of our analytical model of the spatial interstellar extinction variations within the nearest kiloparsec. This model treats the 3D dust distribution as a superposition of three overlapping layers: (1) the layer along…
Interstellar shock waves can erode and destroy grains present in the shocked gas, primarily as the result of sputtering and grain-grain collisions. Uncertainties in current estimates of sputtering yields are reviewed. Results are presented…
Dust in the diffuse interstellar medium remains incompletely understood with regard to the structure, composition, size distribution, and alignment properties of the grains. Joint observations of reddening, starlight polarisation spectra,…
In the interstellar medium of the Milky Way, certain elements -- e.g., Mg, Si, Al, Ca, Ti, Fe -- reside predominantly in interstellar dust grains. These grains absorb, scatter, and emit electromagnetic radiation, heat the interstellar…
The properties of interstellar grains can now be defined by a rapidly growing wealth of observational data. We rely upon models to combine these data with unobserved properties such as the size distribution of grains, their structure and…
The abundance of both amorphous and crystalline silicates in very small grains is limited by the fact that the 10 micron silicate emission feature is not detected in the diffuse ISM. On the basis of the observed IR emission spectrum for the…
We interpret the relation between the polarizing efficiency $P_{\max}/E(B-V)$ and the wavelength of the maximum polarization $\lambda_{\max}$ observed for 17 objects (including 243 stars) separated into two groups: "dark clouds" and "open…
We analyze extragalactic extinction profiles derived through gamma-ray burst afterglows, using a dust model specifically constructed on the assumption that dust grains are not immutable but respond time-dependently to the local physics.…
Interstellar dust grain growth in dense clouds and protoplanetary disks, even moderate, affects the observed interstellar ice profiles as soon as a significant fraction of dust grains is in the size range close to the wave vector at the…
Dust grains grow their sizes in the interstellar clouds (especially in molecular clouds) by accretion and coagulation. Here we model and test these processes by examining the consistency with the observed variation of the extinction curves…