Related papers: Pixie Dust: The Silicate Features in the Diffuse I…
Heavily obscured active galactic nuclei (AGNs) are known to show deep silicate absorption features in the mid-infrared (IR) wavelength range of 10--20~$\mu$m. The detailed profiles of the features reflect the properties of silicate dust,…
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…
This review surveys the observed properties of interstellar dust grains: the wavelength-dependent extinction of starlight, including absorption features, from UV to IR; optical luminescence; IR emission; microwave emission; optical, UV, and…
We analyze the mid-infrared (MIR) spectra of ultraluminous infrared galaxies (ULIRGs) observed with the Spitzer Space Telescope's Infrared Spectrograph. Dust emission dominates the MIR spectra of ULIRGs, and the reprocessed radiation that…
Aims. In this paper we study the Spitzer and TIMMI2 infrared spectra of post-AGB disc sources, both in the Galaxy and the LMC. Using the observed infrared spectra we determine the mineralogy and dust parameters of the discs, and look for…
We report a detection of the 9.7 micrometer silicate absorption feature in a damped Lyman-alpha (DLA) system at z_{abs} = 0.524 toward AO0235+164, using the Infrared Spectrograph (IRS) onboard the Spitzer Space Telescope. The feature shows…
We study the composition of the Galactic interstellar medium (ISM) toward the Galactic center region (5 < |l| < 20 degree) by utilizing X-ray absorption features of three bright low-mass X-ray binaries (LMXBs), GX 13+1, GX 5-1, and GX…
We present a model using the evolution of the stellar population in a starburst galaxy to predict the crystallinity of the silicates in the interstellar medium of this galaxy. We take into account dust production in stellar ejecta, and…
We report the detection and successful modeling of the unusual 9.7\mum Si--O stretching silicate emission feature in the type 1 (i.e. face-on) LINER nucleus of M81. Using the Infrared Spectrograph (IRS) instrument on Spitzer, we determine…
The presence of crystalline silicates has been detected in the circumstellar environment of several young stars in the recent past and there is evidence of silicon carbide (SiC) detection in the envelope of pre-main sequence star SVS13. In…
Mid-Infrared (IR) silicate dust bands observed in heavily obscured active galactic nuclei (AGNs) include information on the mineralogical properties of silicate dust. We aim to investigate the mineralogical picture of the circumnuclear…
Dust grains in the planet forming regions around young stars are expected to be heavily processed due to coagulation, fragmentation and crystallization. This paper focuses on the crystalline silicate dust grains in protoplanetary disks. As…
Silicate minerals belong to the most abundant solids in space. Their formation becomes difficult at the transition from the oxygen rich chemistry of M-stars to the carbon rich chemistry of C-stars. In the intermediate type S-stars oxygen…
Investigating the chemical complexity of the interstellar medium (ISM) is key for understanding its physical nature and evolution. In this work, we study parsec-scale interstellar dust clouds in the neutral ISM of the Milky Way using two…
We investigate the occurrence of crystalline silicates in oxygen-rich evolved stars across a range of metallicities and mass-loss rates. It has been suggested that the crystalline silicate feature strength increases with increasing…
We present the Spitzer IRS spectra for 33 young stars in Tr 37 and NGC 7160. The sample includes the high- and intermediate-mass stars with MIPS 24 microns excess, the only known active accretor in the 12 Myr-old cluster NGC 7160, and 19…
The composite grain is made up of a host silicate spheroid and graphite inclusions. The extinction efficiencies of the composite spheroidal grains for three axial ratios are computed using the discrete dipole approximation (DDA). 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…
We present 8-13 micron imaging and spectroscopy of 9 type 1 and 10 type 2 AGN obtained with the VLT/VISIR instrument at spatial resolution <100 pc. The emission from the host galaxy sources is resolved out in most cases. The silicate…
The interstellar abundances of refractory elements indicate a substantial depletion from the gas phase, that increases with gas density. Our recent model of dust evolution, based on hydrodynamic simulations of the lifecycle of giant…