Related papers: Silicon Nanoparticles: Source of Extended Red Emis…
To examine a recently proposed hypothesis that silicon nanoparticles are the source of extended red emission (ERE) in the interstellar medium, we performed a detailed modeling of the mean Galactic extinction in the presence of silicon…
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…
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 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…
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…
The carrier of the dust-associated photoluminescence process causing the extended red emission (ERE) in many dusty interstellar environments remains unidentified. Several competing models are more or less able to match the observed broad,…
We analysed new wide-field, wide- and narrow-band optical images of IC 59 and IC 63, two nebulae which are externally illuminated by the early B-star {\gamma} Cas, with the objective of mapping the extended red emission (ERE), 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…
Low-dispersion spectra have been obtained from 4000 to 9600 \AA~along the axis and across the dusty halo of the galaxy M82. The spectra of the halo are explained in terms of scattering of the galactic light by dust grains: when divided by…
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…
We obtained low-resolution, long-slit 5300--9100 A spectroscopy of NGC4826 (a nearby galaxy with an absorbing dust lane (DL) asymmetrically placed across its bulge, associated with several HII regions) with a slit encompassing its bulge,…
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…
The dense Galactic environment is a large reservoir of interstellar dust. Therefore, this region represents a perfect laboratory to study the properties of the cosmic dust grains. X-rays are the most direct way to detect the interaction of…
Extended Red Emission (ERE) is a widely observed optical emission process, present in a wide range of circumstellar and interstellar environments in the Milky Way galaxy as well as other galaxies. Definitive identifications of the ERE…
The wavelength dependences of interstellar extinction and polarization, supplemented by observed elemental abundances and the spectrum of infrared emission from dust heated by starlight, strongly constrain dust models. One dust model that…
Possible forsterite nanoparticle model of the Extended Red Emission(ERE) is proposed on the basis of photo-luminescence of forsterite after gamma-ray and neutron irradiation. Forsterite exhibits interesting thermoluminescence spectrum…
The interstellar medium is enriched primarily by matter ejected from evolved low and intermediate mass stars. The outflows from these stars create a circumstellar envelope in which a rich gas-phase and dust-nucleation chemistry takes place.…
Extended Red Emission (ERE) was recently attributed to the photo-luminescence of either doubly ionized Polycyclic Aromatic Hydrocarbons (PAH$^{++}$), or charged PAH dimers. We analysed the visible and mid-infrared (mid-IR) dust emission in…