Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physical Sciences and Mathematics
Star Formation In Self-Gravitating Disks In Active Galactic Nuclei. I. Metallicity Gradients In Broad-Line Regions, Jian-Min Wang, Jun-Qiang Ge, Chen Hu, Jack A. Baldwin, Yan-Rong Li, Gary J. Ferland, Fei Xiang, Chang-Shuo Yan, Shu Zhang
Star Formation In Self-Gravitating Disks In Active Galactic Nuclei. I. Metallicity Gradients In Broad-Line Regions, Jian-Min Wang, Jun-Qiang Ge, Chen Hu, Jack A. Baldwin, Yan-Rong Li, Gary J. Ferland, Fei Xiang, Chang-Shuo Yan, Shu Zhang
Physics and Astronomy Faculty Publications
It has been suggested that the high metallicity generally observed in active galactic nuclei (AGNs) and quasars originates from ongoing star formation in the self-gravitating part of accretion disks around supermassive black holes (SMBHs). We designate this region as the star-forming (SF) disk, in which metals are produced from supernova explosions (SNexp) while at the same time inflows are driven by SNexp-excited turbulent viscosity to accrete onto the SMBHs. In this paper, an equation of metallicity governed by SNexp and radial advection is established to describe the metal distribution and evolution in the SF disk. We find that the metal …
Emission From Hot Dust In The Infrared Spectra Of Gamma-Ray Bright Blazars, Michael P. Malmrose, Alan P. Marscher, Svetlana G. Jorstad, Robert Nikutta, Moshe Elitzur
Emission From Hot Dust In The Infrared Spectra Of Gamma-Ray Bright Blazars, Michael P. Malmrose, Alan P. Marscher, Svetlana G. Jorstad, Robert Nikutta, Moshe Elitzur
Physics and Astronomy Faculty Publications
A possible source of γ-ray photons observed from the jets of blazars is inverse Compton scattering by relativistic electrons of infrared seed photons from a hot, dusty torus in the nucleus. We use observations from the Spitzer Space Telescope to search for signatures of such dust in the infrared spectra of four γ-ray bright blazars, the quasars 4C 21.35, CTA102, and PKS 1510-089, and the BL Lacertae object ON231. The spectral energy distribution (SED) of 4C 21.35 contains a prominent infrared excess indicative of dust emission. After subtracting a non-thermal component with a power-law spectrum, we fit a …
Dusty Tori Of Luminous Type 1 Quasars At Z ~ 2, Rajesh P. Deo, Gordon T. Richards, Robert Nikutta, Moshe Elitzur, Sarah C. Gallagher, Željko Ivezić, Dean Hines
Dusty Tori Of Luminous Type 1 Quasars At Z ~ 2, Rajesh P. Deo, Gordon T. Richards, Robert Nikutta, Moshe Elitzur, Sarah C. Gallagher, Željko Ivezić, Dean Hines
Physics and Astronomy Faculty Publications
We present Spitzer infrared (IR) spectra and ultraviolet (UV) to mid-IR spectral energy distributions (SEDs) of 25 luminous type 1 quasars at z ~ 2. In general, the spectra show a bump peaking around 3 μm and the 10 μm silicate emission feature. The 3 μm emission is identified with hot dust emission at its sublimation temperature. We explore two approaches to modeling the SED: (1) using the CLUMPY model SED from Nenkova et al. and (2) the CLUMPY model SED and an additional blackbody component to represent the 3 μm emission. In the first case, …