Related papers: Silicate Extinction Profile Based on the Stellar S…
The 9.7$\mu$m interstellar spectral feature, arising from the Si--O stretch of amorphous silicate dust, is the strongest extinction feature in the infrared (IR). In principle, the spectral profile of this feature could allow one to diagnose…
We measured the mid-infrared (MIR) extinction using Spitzer photometry and spectroscopy (3.6--37 micron) for a sample of Milky Way sightlines (mostly) having measured ultraviolet extinction curves. We used the pair method to determine the…
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…
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…
Studying the composition of dust in the interstellar medium (ISM) is crucial in understanding the cycle of dust in our galaxy. The mid-infrared spectral signature of amorphous silicates, the most abundant dust species in the ISM, is studied…
We have examined the relationship between the optical depth of the 9.7 micron silicate absorption feature (tau_9.7) and the near-infrared color excess, E(J-Ks) in the Serpens, Taurus, IC 5146, Chameleon I, Barnard 59, and Barnard 68 dense…
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 a comprehensive study of the silicate features at 9.7 and 18 micron of a sample of almost 800 active galactic nuclei (AGN) with available spectra from the Spitzer InfraRed Spectrograph (IRS). We measure the strength of the…
We present the initial results of MEAD (Measuring Extinction and Abundances of Dust), with a focus on the dust extinction features observed in our JWST near- and mid-infrared spectra of nine diffuse Milky Way sightlines ($1.2 \leq A(V) \leq…
Interstellar dust extinction curves provide valuable information about dust properties, including the composition and size of the dust grains, and are essential to correct observations for the effects of interstellar dust. In this work, we…
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…
New multi-epoch, mid-infrared (8-13 microns) spectrophotometric observations are presented for 30~late-type stars. The observations were collected over a four year period (1994-1997), permitting an investigation of the mid-infrared spectral…
We obtained low resolution (R = 100) mid-infrared (8-13 micron wavelengths) spectra of 8 nearby young main sequence stars with the Keck 1 telescope and Long-Wavelength Spectrometer (LWS) to search for 10 micron silicate (Si-O stretch)…
In the framework of the silicate core-carbonaceous organic mantle interstellar dust model, the bulk of the visual/near-IR extinction and the entire polarization are from nonspherical and aligned core-mantle grains. The 3.4 micron C-H and…
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…
We have studied the dust along the line-of-sight towards the Galactic Center using Short Wavelength Spectrometer (SWS) data obtained with the Infrared Space Observatory (ISO). We focussed on the wavelength region from 8-13 micron which is…
We present results from a mini-survey of dust spectral features arising in galaxies at redshifts $0.5 < z < 1.2$ in our James Webb Space Telescope (JWST) mid-infrared spectra of physically-unrelated background quasars. We analyze the JWST…
The 9.7-micron silicate absorption profile in the interstellar medium provides important information on the physical and chemical composition of interstellar dust grains. Measurements in the Milky Way have shown that the profile in the…
We present a photometric selection method for ULIRGs in the redshift range of z=1 -- 2. We utilize the most prominent spectral feature of ULIRGs, i.e. the silicate absorption feature at 9.7 micron and an optimized filter system at…
In order to investigate possible connections between dust processing and disk properties, 8--13 um spectra of 34 young stars, with a range of circumstellar environments and spectral types A to M, were obtained using the Long Wavelength…