Hot Graphite Dust and the Infrared Spectral Energy Distribution of Active Galactic Nuclei

Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13 figures and 1 table; MNRAS in press

Scientific paper

We present a detailed investigation of the near-to-far infrared (IR) spectral energy distribution (SED) of a large sample of Spitzer-observed active galactic nuclei (AGN). We fitted the spectra of 51 narrow line Seyfert 1 galaxies (NLS1s) and 64 broad line Seyfert 1 galaxies (BLS1s) using a three component model: a clumpy torus, a dusty narrow line region (NLR) and hot pure-graphite dust located in the outer part of the broad line region (BLR). The fitting is performed on star formation (SF) subtracted SEDs using SF templates that take into account the entire range of possible host galaxy properties. We find that the mid-IR intrinsic emission of NLS1s and BLS1s are very similar, regardless of the AGN luminosity, with long wavelength downturn at around 20-25 um. We present a detailed model of the hot dust component that takes into account the distribution of dust temperature within the clouds and their emission line spectrum. The hot dust continuum provides a very good fit to the observed near-IR continuum spectrum. Most line emission in this component is dramatically suppressed, except MgII(2798A) and HeI lines that are still contributing significantly to the total BLR spectrum. We calculate the covering factors of all the AGN components and show that the covering factor of the hot-dust clouds is about 0.15-0.35, similar to the covering factor of the torus, and is anti-correlated with the source luminosity and the normalized accretion rate.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Hot Graphite Dust and the Infrared Spectral Energy Distribution of Active Galactic Nuclei does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hot Graphite Dust and the Infrared Spectral Energy Distribution of Active Galactic Nuclei, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hot Graphite Dust and the Infrared Spectral Energy Distribution of Active Galactic Nuclei will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-93480

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.