Related papers: Silicon nanoparticles and interstellar extinction
We have reviewed the characteristics of the extended red emission (ERE) as observed in many dusty astronomical environments, in particular, the diffuse interstellar medium of the Galaxy. The spectral nature and the photon conversion…
Silicon nanoparticles (SNPs) have been proposed as the source of the observed "extended red emission" (ERE) from interstellar dust. We calculate the thermal emission expected from such particles in a reflection nebula such as NGC 2023, and…
Interstellar dust contains a component which reveals its presence by emitting a broad, unstructured band of light in the 540 to 950 nm wavelength range, referred to as Extended Red Emission (ERE). The presence of interstellar dust and…
Interstellar dust in nebulae and in the diffuse interstellar medium of galaxies contains a component which responds to illumination by ultraviolet photons with efficient luminescence in the 500 nm to 1000 nm spectral range, known as…
Nearby interstellar clouds at high Galactic latitudes are ideal objects in which the interaction of interstellar dust with photons from the well-characterized interstellar radiation field can be studied. Scattering and UV-excited…
Depletion studies provide a way to understand the chemical composition of interstellar dust grains. We here examine 23 gamma-ray bursts (GRB) optical afterglow spectra (spanning 0.6<z<5.0) and compare their silicon and iron dust-phase…
We interpret the interstellar extinction observed towards the Galactic Center (GC) in the wavelength range $\lambda = 1 - 20\,\mkm$. Its main feature is the flat extinction at $3 - 8\,\mkm$ whose explanation is still a problem for the…
Spinning small silicate grains were recently invoked to account for the Galactic foreground anomalous microwave emission. These grains, if present, will absorb starlight in the far ultraviolet (UV). There is also renewed interest in…
The composition and properties of interstellar silicate dust are not well understood. In X-rays, interstellar dust can be studied in detail by making use of the fine structure features in the Si K-edge. The features in the Si K-edge offer a…
We present 0.35 to 2.5 micron spectra of the south and northwest filaments in the reflection nebula NGC 7023. These spectra were used to test the theory of Seahra & Duley that carbon nanoparticles are responsible for Extended Red Emission…
Interstellar grains span a wide range of sizes from a few angstroms to a few micrometers. The presence of nanometer-sized or smaller particles in the interstellar medium is indicated directly by the interstellar far ultraviolet (UV)…
In 1998 Gordon, Witt and Friedmann wrote of detection of ERE in diffuse galactic light at high latitudes. The comparaison of diffuse galactic light and starlight over a few regions of the sky cannot, according to the authors, be fully…
How dust scatters and absorbs starlight in the interstellar medium (ISM) contains important clues about the size and composition of interstellar dust. While the ultraviolet (UV) and visible interstellar extinction is well studied and can be…
We present initial results from the first optical spectroscopic survey of high latitude Galactic cirrus clouds. The observed shape of the cirrus spectrum does not agree with that of scattered ambient Galactic starlight. This mismatch can be…
Observations of interstellar extinction and polarization indicate that the interstellar medium consists of aligned non-spherical dust grains which show variation in the interstellar extinction curve for wavelengths ranging from NIR to UV.…
Tin-containing nanocrystals, embedded in silicon, have been fabricated by growing an epitaxial layer of Si_{1-x-y}Sn_{x}C_{y}, where x = 1.6 % and y = 0.04 %, followed by annealing at various temperatures ranging from 650 to 900 degrees C.…
The extinction curve derived from ISO mid-infrared (IR) observations of the Galactic center (GC) exhibits a surprisingly flat behavior in the ~ 3 to 8 micron region, contrary to the deep minimum expected from standard interstellar dust…
A composite dust grain model which simultaneously explains the observed interstellar extinction, polarization, IR emission and the abundance constraints, is required. We present a composite grain model, which is made up of a host silicate…
Dust particles play a major role in the formation, evolution and chemistry of interstellar clouds, stars and planetary systems. Commonly identified forms include amorphous and crystalline carbon-rich particles and silicates. Also present in…
Extended Red Emission (ERE) has been detected in many dusty astrophysical objects and this raises the question: Is ERE present only in discrete objects or is it an observational feature of all dust, i.e. present in the diffuse interstellar…