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Using Chandra and HST archival data, we have studied the individual Spectral Energy Distribution (SED) of 11 quasars. All UV spectra show a spectral break around 1100A. 5 X-ray spectra show the presence of a ``soft excess'' and 7 spectra…

We use infrared spectroscopy and photometry to empirically define the intrinsic, thermal infrared spectral energy distribution (i.e., 6-100 um SED) of typical active galactic nuclei (i.e., 2-10 keV luminosity, Lx=10^{42}-10^{44} ergs/s…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 J. R. Mullaney , D. M. Alexander , A. D. Goulding , Ryan C. Hickox

Averaged spectral energy distributions (SEDs) of active and starburst galaxies from the 12 micron sample in the Local Universe and Quasars, from an optically selected sample at a mean redshift <z>=0.7, are built from optical/near-IR/far-IR…

Astrophysics · Physics 2009-11-10 Paola Andreani , Luigi Spinoglio , Matthew A. Malkan

Spectral Energy Distribution (SED) of the broad-band continuum emission from black-hole accretion discs can serve as a tool to measure parameters of the central body and constrain the geometry of the inner accretion flow. We focus on the…

High Energy Astrophysical Phenomena · Physics 2023-06-21 Marcel Štolc , Michal Zajaček , Bożena Czerny , Vladimír Karas

We present the 970-1175 A spectral energy distributions (SEDs) of 12 starburst galaxies observed with the Far Ultraviolet Spectroscopic Explorer FUSE. We take benefit of the high spectral resolution of FUSE to estimate a continuum as much…

Astrophysics · Physics 2009-11-07 V. Buat , D. Burgarella , J. M. Deharveng , D. Kunth

We present a 5-8 micron analysis of the Spitzer-IRS spectra of 71 ultraluminous infrared galaxies (ULIRGs) with redshift z < 0.15, devoted to the study of the role of active galactic nuclei (AGN) and starbursts (SB) as the power source of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 E. Nardini , G. Risaliti , M. Salvati , E. Sani , Y. Watabe , A. Marconi , R. Maiolino

We present near and mid--IR observations of a sample of Seyfert II galaxies drawn from the $12\mu$m Galaxy Sample. The sample was observed in the J, H, K, L, M and N bands. Galaxy Surface Brightness Profiles are modeled using nuclear,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Liza Videla , Paulina Lira , Heather Andrews , Almudena Alonso-Herrero , David M. Alexander , Martin Ward

We present quasi-simultaneous multi-colour optical/near-IR photometry for 157 radio selected quasars, forming an unbiassed sub-sample of the Parkes Flat-Spectrum Sample. Data are also presented for 12 optically selected QSOs, drawn from the…

Astrophysics · Physics 2015-06-24 Paul J. Francis , Matthew T. Whiting , Rachel L. Webster

The rest-frame ultraviolet (UV) spectra of active galactic nuclei (AGNs) are important diagnostics of both accretion disk physics and their contribution to the metagalactic ionizing UV background. Though the mean AGN spectrum is well…

Astrophysics of Galaxies · Physics 2016-01-27 Evan M. Tilton , Matthew L. Stevans , J. Michael Shull , Charles W. Danforth

We present one of the largest multiwavelength studies of simultaneous optical-to-X-ray spectral energy distributions (SEDs) of unobscured active galactic nuclei (AGN) in the local Universe. Using a representative sample of…

Theory and observations of the dominant thermal continuum emission in AGNs are examined. After correction for reddening, the steady state AGN optical--UV spectral energy distributions (SEDs) are very similar. The SEDs are dominated…

Astrophysics · Physics 2007-11-15 C. Martin Gaskell

Spectral energy distributions (SEDs) from X-ray to far-infrared (FIR) wavelengths are presented for a sample of 1246 X-ray luminous active galactic nuclei (AGN; $L_{0.5-10\rm{keV}}>10^{43}$ erg s$^{-1}$), with $z_{\rm{spec}}<1.2$, selected…

We employ contemporaneous optical, UV and X-ray observations from the XMM-Newton EPIC-pn and Optical Monitor (OM) archives to present, for the first time, simultaneous spectral energy distributions (SEDs) for the majority of the Peterson et…

Astrophysics · Physics 2009-11-13 R. V. Vasudevan , A. C. Fabian

We measure the bolometric luminosity of a complete and unbiased 12 micron-selected sample of active galactic nuclei (AGN) in the local Universe. For each galaxy we used a 10-band radio-to-X-ray Spectral Energy Distribution (SED) to isolate…

Astrophysics of Galaxies · Physics 2023-12-22 Luigi Spinoglio , Juan Antonio Fernandez-Ontiveros , Matthew A. Malkan

Active Galactic Nuclei (AGN) are multiwavelength emitters. To have any hope of understanding them, or even to determine their energy output, we must observe them with many telescopes. I will review what we have learned from broad-band…

Astrophysics · Physics 2007-05-23 Belinda J. Wilkes

The All-wavelength Extended Groth Strip International Survey (AEGIS) team presents broad-band spectral energy distributions (SEDs), from X-ray to radio wavelengths, for 71 galaxies spanning the redshift range 0.55-1.16 (<z>~0.7). Galaxies…

This is the second paper studying the QSOs in the spitzer QUEST sample. Previously we presented new PAH measurements and argued that most of the observed far infrared (FIR) radiation is due to star-forming activity. Here we present spectral…

A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to evaluate the intervening radiative mechanisms responsible for the observed emission and relate them with the underlying accretion physics. We present wide frequency…

We present a compilation of spectral energy distributions of 35 weak AGNs in LINERs using recent data from the published literature. We make use of previously published compilations of data, after complementing and extending them with more…

Astrophysics of Galaxies · Physics 2015-05-18 Michael Eracleous , Jason A. Hwang , Helene M. L. G. Flohic

We assemble a sample of 696 type 1 AGN up to a redshift of $z=2.5$, all of which have an SDSS spectrum containing at least one broad emission line (H $\alpha$, H $\beta$ or Mg II) and an XMM-Newton X-ray spectrum containing at least 250…

Astrophysics of Galaxies · Physics 2023-02-01 Daniel Kynoch , Jake A. J. Mitchell , Martin J. Ward , Chris Done , Elisabeta Lusso , Hermine Landt