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Full-Text Articles in Physical Sciences and Mathematics
Contribution Of The Accretion Disk, Hot Corona, And Obscuring Torus To The Luminosity Of Seyfert Galaxies: Integral And Spitzer Observations, S. Sazonov, S. P. Willner, A. D. Goulding, R. C. Hickox
Contribution Of The Accretion Disk, Hot Corona, And Obscuring Torus To The Luminosity Of Seyfert Galaxies: Integral And Spitzer Observations, S. Sazonov, S. P. Willner, A. D. Goulding, R. C. Hickox
Dartmouth Scholarship
We estimate the relative contributions of the supermassive black hole (SMBH) accretion disk, corona, and obscuring torus to the bolometric luminosity of Seyfert galaxies, using Spitzer mid-infrared (MIR) observations of a complete sample of 68 nearby active galactic nuclei (AGNs) from the INTEGRAL all-sky hard X-ray (HX) survey. This is the first HX-selected (above 15 keV) sample of AGNs with complementary high angular resolution, high signal-to-noise, MIR data. Correcting for the host galaxy contribution, we find a correlation between HX and MIR luminosities: L 15 μm∝L0.74 ± 0.06 HX. Assuming that the observed MIR emission is radiation …
Deep Silicate Absorption Features In Compton-Thick Active Galactic Nuclei Predominantly Arise Due To Dust In The Host Galaxy, A. D. Goulding, D. M. Alexander, F. E. Bauer, W. R. Forman, R. C. Hickox
Deep Silicate Absorption Features In Compton-Thick Active Galactic Nuclei Predominantly Arise Due To Dust In The Host Galaxy, A. D. Goulding, D. M. Alexander, F. E. Bauer, W. R. Forman, R. C. Hickox
Dartmouth Scholarship
We explore the origin of mid-infrared (mid-IR) dust extinction in all 20 nearby (z < 0.05) bona fide Compton-thick (N H > 1.5 × 1024 cm–2) active galactic nuclei (AGNs) with hard energy (E > 10 keV) X-ray spectral measurements. We accurately measure the silicate absorption features at λ ~ 9.7 μm in archival low-resolution (R ~ 57-127) Spitzer Infrared Spectrograph spectroscopy, and show that only a minority (≈45%) of nearby Compton-thick AGNs have strong Si-absorption features (S 9.7 = ln (f int/f obs) 0.5) which would indicate significant dust attenuation. The majority (≈60%) are star …