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Related papers: Extinction curves in AGN

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We present observational evidences that dust in the circumnuclear region of AGNs has different properties than in the Galactic diffuse interstellar medium. By comparing the reddening of optical and infrared broad lines and the X-ray…

Astrophysics · Physics 2009-10-31 R. Maiolino , A. Marconi , M. Salvati , G. Risaliti , P. Severgnini , F. La Franca , L. Vanzi

In a companion paper, Maiolino et al. (2000) presented various observational evidences for "anomalous" dust properties in the circumnuclear region of AGNs and, in particular, the reduced E(B-V)/N_H and Av/N_H ratios, the absence of the…

Astrophysics · Physics 2009-10-31 R. Maiolino , A. Marconi , E. Oliva

We present extinction curves derived from the broad emission lines and continua of large samples of both radio-loud and radio-quiet AGNs. The curves are significantly flatter in the UV than are curves for the local ISM. The reddening curves…

The dust extinction curve is a critical component of many observational programs and an important diagnostic of the physics of the interstellar medium. Here we present new measurements of the dust extinction curve and its variation towards…

Dust plays a central role in the unification theory of active galactic nuclei (AGNs). Whether the dust that forms the torus around an AGN is tenth-$\mu$m-sized like interstellar grains or much larger has a profound impact on correcting for…

Astrophysics of Galaxies · Physics 2017-05-10 Z. Z. Shao , B. W. Jiang , Aigen Li

We present intrinsic extinction curves for 14 AGNs. The AGNs have reddenings, E(B-V), of up to 0.36 mag. The majority (13 out of 14) of the extinction curves are not steep in the UV. Of the seven best determined extinction curves, five have…

Astrophysics · Physics 2007-11-08 C. Martin Gaskell , A. J. Benker

The dust extinction curve is typically parameterized by a single variable, R(V), in optical and near-infrared wavelengths. R(V) controls the slope of the extinction-vs.-wavelength curve, and is thought to reflect the grain-size distribution…

Astrophysics of Galaxies · Physics 2025-06-26 Gregory M. Green , Xiangyu Zhang , Ruoyi Zhang

The composition and amount of interstellar dust within gamma-ray burst (GRB) host galaxies is of key importance when addressing selection effects in the GRB redshift distribution, and when studying the properties of their host galaxies. As…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. Schady , T. Dwelly , M. J. Page , T. Krühler , J. Greiner , S. R. Oates , M. De Pasquale , M. Nardini , P. W. A. Roming , A. Rossi , M. Still

Fundamental properties of the extinction curve, like the slope in the rest-frame UV and the presence/absence of a broad absorption excess centred at 2175A (the UV bump), are investigated for a sample of 108 massive, star-forming galaxies at…

Astrophysics · Physics 2007-05-23 Stefan Noll , Daniele Pierini , Maurilio Pannella , Sandra Savaglio

Fundamental properties of the extinction curve, like the slope in the rest-frame ultraviolet (UV) and the presence/absence of a broad absorption excess centred at 2175 A (the UV bump), are investigated for a sample of 108 massive,…

Astrophysics · Physics 2009-11-13 S. Noll , D. Pierini , M. Pannella , S. Savaglio

Understanding the properties and physical mechanisms that shape dust attenuation curves in galaxies is one of the fundamental questions of extragalactic astrophysics, with a great practical significance for deriving the physical properties…

Astrophysics of Galaxies · Physics 2020-11-11 Samir Salim , Desika Narayanan

Dust plays an essential role in the unification theory of active galactic nuclei (AGNs). This review summarizes our current understanding of the extinction and infrared emission properties of the circumnuclear dust in AGNs as well as the…

Astrophysics · Physics 2008-09-01 Aigen Li

Interstellar dust plays a central role in shaping the detailed structure of the interstellar medium, thus strongly influencing star formation and galaxy evolution. Dust extinction provides one of the main pillars of our understanding of…

In order to study the effect of dust extinction on the afterglow of gamma-ray bursts (GRBs), we carry out numerical calculations with high precision based on rigorous Mie theory and latest optical properties of interstellar dust grains, and…

High Energy Astrophysical Phenomena · Physics 2011-08-26 Gu-Jing Lv , Lang Shao , Zhi-Ping Jin , Da-Ming Wei

The large majority of extinction sight lines in our Galaxy obey a simple relation depending on one parameter, the total-to-selective extinction coefficient, Rv. Different values of Rv are able to match the whole extinction curve through…

Astrophysics of Galaxies · Physics 2015-05-20 Paola Mazzei , Guido Barbaro

Dust plays a central role in the unification theory of active galactic nuclei (AGNs). However, little is known about the nature (e.g., size, composition) of the dust which forms a torus around the AGN. In this Letter we report a systematic…

Astrophysics of Galaxies · Physics 2015-06-22 Jianwei Lyu , Lei Hao , Aigen Li

Interstellar dust is a major foreground contaminant for many observations and a key component in the chemistry of the interstellar medium, yet its properties remain highly uncertain. Using low-resolution spectra, we accurately measure the…

Astrophysics of Galaxies · Physics 2024-07-23 Xiangyu Zhang , Gregory Green

Extinction curves contain key information on interstellar dust composition and size distribution, with the 2175 {\AA} bump being the most prominent feature. We analyze 20 sightlines toward M31 using HST/STIS UV spectroscopy combined with…

Astrophysics of Galaxies · Physics 2026-01-01 Bing Yan , Shu Wang , Jian Gao , Yuxi Wang , Bingqiu Chen

To understand the evolution of extinction curve, we calculate the dust evolution in a galaxy using smoothed particle hydrodynamics simulations incorporating stellar dust production, dust destruction in supernova shocks, grain growth by…

Astrophysics of Galaxies · Physics 2017-05-31 Kuan-Chou Hou , Hiroyuki Hirashita , Kentaro Nagamine , Shohei Aoyama , Ikkoh Shimizu

Dust in the host galaxies of gamma-ray bursts (GRBs) dims and reddens their afterglow spectra. Knowledge of the nature of this dust is crucial for correcting for extinction, providing clues to the nature of GRB progenitors, and probing the…

Astrophysics · Physics 2009-11-11 Shilun Chen , Aigen Li , Daming Wei
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