Related papers: Extinction curves in AGN
Any distortion of a chemical structure causes new features to appear in the absorption spectrum of the structure, especially in the visible and near UV (see Paper I). Chemical modeling, using molecular orbital theory, showed that the…
We report the detection of a 9.7 $\mu$m silicate dust absorption feature toward the Cygnus A nucleus. Its optical depth is, however, significantly smaller than that expected from the dust extinction toward the background $L$-band emission…
The effects of dust extinction on the departure from axi-symmetry in the morphology of planetary nebulae (PNs) are investigated through a comparison of the radio free-free emission and hydrogen recombination line images. The dust…
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…
The most striking characteristics of the mysterious 2175 Angstrom extinction bump, the strongest spectroscopic absorption feature seen on the interstellar extinction curve, are the invariant central wavelength and variable bandwidth: its…
To investigate the properties of dust in the nuclear region of quasars, we explored the extinction curves of the iron low-ionization broad absorption line (FeLoBAL) quasar SDSS J163004.29+311957.6 and its two analogues. The parameterized…
The internal dust extinction in spiral galaxies can affect our understanding of their structure and morphology, as well as our perception of the distant universe in the background. The intrinsic properties of the stellar and dust components…
A novel technique is employed for estimating attenuation curves in galaxies where only photometry and spectroscopic redshifts are available. This technique provides a powerful measure of particular extinction features such as the UV bump at…
Dust is observed in the polar regions of nearby AGN and it is known to contribute substantially to their mid-IR emission and to the obscuration of their UV to optical emission. We selected a sample of 1275 BLAGN in the XMM-XXL field, with…
Dust reprocesses the intrinsic radiation of active galactic nuclei (AGNs) to emerge at longer wavelengths. The observed mid-infrared (MIR) luminosity depends fundamentally on the luminosity of the central engine, but in detail it also…
We analyze the optical-near infrared spectra of 33 quasars with redshifts 3.9<z<6.4 to investigate the properties of dust extinction at these cosmic epochs. The SMC extinction curve has been shown to reproduce the dust reddening of most…
We critique the method of constructing extinction curves of lensing galaxies using multiply imaged QSOs. If one of the two QSO images is lightly reddened or if the dust along both sightlines has the same properties then the method works…
The characterisation of the extinction curve in the near infrared (NIR) is fundamental to analyse the structure and stellar population of the Galactic centre (GC), whose analysis is hampered by the extreme interstellar extinction ($A_V\sim…
We use mid-infrared spectroscopy of unobscured active galactic nuclei (AGNs) to reveal their native dusty environments. We concentrate on Seyfert 1 galaxies, observing a sample of 31 with the Infrared Spectrograph aboard the Spitzer Space…
When measuring star formation rates using ultraviolet light, correcting for dust extinction is a critical step. However, with the variety of dust extinction curves to choose from, the extinction correction is quite uncertain. Here, we use…
GRB afterglows are well suited to extinction studies due to their brightness, simple power-law spectra and the occurrence of GRBs in distant star forming galaxies. In this paper we present results from the SED analysis of a sample of 41 GRB…
Physical processes such as re-ignition, enhancement, and fading of active galactic nuclei (AGN) are not entirely understood because the timeline of these events is expected to last many years. However, it is well known that the differences…
We use observed optical to near infrared spectral energy distributions (SEDs) of 266 galaxies in the COSMOS survey to derive the wavelength dependence of the dust attenuation at high redshift. All of the galaxies have spectroscopic…
While it is well recognized that both the Galactic interstellar extinction curves and the gas-phase abundances of dust-forming elements exhibit considerable variations from one sight line to another, as yet most of the dust extinction…
Infrared continuum observations provide a means of investigating the physical composition of the dust in the ejecta and swept up medium of the Cas A supernova remnant. Using low resolution Spitzer IRS spectra (5-35 $\mu$m), and broad-band…