Related papers: Testing the AGN Unification Model in the Infrared
We have analyzed the broadband X-ray spectra of active galactic nuclei (AGNs) in two "non-merging" luminous infrared galaxies (LIRGs) UGC 2608 and NGC 5135, utilizing the data of NuSTAR, Suzaku, XMM-Newton, and Chandra. Applying the X-ray…
We present new frontiers in the modelling of the spectral energy distributions (SED) of active galaxies by introducing the radio-to-X-ray fitting capabilities of the publicly available Bayesian code AGNfitter. The new code release, called…
High quality infrared spectra of active galaxies including the stellar absorption features of Si at 1.59 um, CO(6,3) at 1.62 um, and CO(2,0) at 2.29 um are used to measure the stellar mass to light ratio at 1.65 um (M_H/L) and investigate…
According to the unified model, the differences observed in different classes of AGN are due to anisotropic obscuration. This implies that in the hard X-rays, at energies where the radiation can pierce the obscuring material, the average…
We present results from Chandra observations of 14 ultraluminous infrared galaxies (ULIRGs; log(L_IR/L_Sun) >= 12) with redshifts between 0.04 and 0.16. The goals of the observations were to investigate any correlation between infrared…
1ES 1927+654 is an active galactic nucleus (AGN) that appears to defy the unification model. It exhibits a type-2 optical spectrum, but possesses little X-ray obscuration. XMM-Newton and Suzaku observations obtained in 2011 are used to…
The narrow Fe K$\alpha$ line is one of the main signatures of the reprocessing of X-ray radiation from the material surrounding supermassive black holes, and it has been found to be omnipresent in the X-ray spectra of active galactic nuclei…
Estimating physical quantities such as the star formation rate, stellar mass and active galactic nucleus (AGN) fraction of galaxies is a key step in understanding galaxy formation and evolution. In order to estimate the uncertainties in the…
We present 180 AGN candidates based on color selection from the IRAS slow-scan deep observations, with color criteria broadened from the initial Point-Source Catalog samples to include similar objects with redshifts up to z=1 and allowing…
Context: A long-standing challenge of observational AGN research is to find type 2 quasars, the luminous analogues of Seyfert-2 galaxies. Aims: We search for luminous narrow-line type 2 AGN, characterise their properties, and compare them…
We explore host galaxy properties and environment of a sample of Type 1 and 2 active galactic nuclei (AGN) taken from the COSMOS2015 catalog, within 0.3 $\leq z \leq$ 1.1 selected for their emission in X-rays, optical spectra and SED…
Deep surveys of {\em Chandra} and {\em HST} (Hubble Space Telescope) show that active galactic nucleus (AGN) populations are changing with hard X-ray luminosities. This arises an interesting question whether the dusty torus is evolving with…
We present ongoing work on the spectral energy distributions (SEDs) of active galactic nuclei (AGNs), derived from X-ray, ultraviolet, optical, infrared and radio photometry and spectroscopy. Our work is motivated by new wide-field imaging…
We present an atlas of mid-infrared (mid-IR) ~7.5-13micron spectra of 45 local active galactic nuclei (AGN) obtained with CanariCam on the 10.4m Gran Telescopio CANARIAS (GTC) as part of an ESO/GTC large program. The sample includes…
The spectral energy distributions and infrared (IR) spectra of a sample of obscured AGNs selected in the mid-IR are modeled with recent clumpy torus models to investigate the nature of the sources, the properties of the obscuring matter,…
The "torus" is the central element of the most popular theory unifying various classes of AGNs, but it is usually described as "putative" because it has not been imaged yet. Since it is too small to be resolved with single-dish telescopes,…
The morphology of a galaxy reflects the mix of physical processes occurring within and around it, offering indirect clues to its formation and evolution. We apply both visual classification and computer vision to test the suspected…
Far-Infrared (FIR) photometry from the the Photodetector Array Camera and Spectrometer (PACS) on the Herschel Space Observatory is presented for 313 nearby, hard X-ray selected galaxies from the 58-month Swift Burst Alert Telescope (BAT)…
Spitzer/IRS has revealed many sources with very deep Si features at 9.7micron (tau>1). We set out to investigate whether a strong Si absorption feature is a good indicator for the presence of a heavily obscured AGN. We compile X-ray…
We present high-resolution mid-infrared (MIR) imaging, nuclear spectral energy distributions (SEDs) and archival Spitzer spectra for 22 low-luminosity active galactic nuclei (LLAGN; Lbol \lesssim 10^42 erg/sec). Infrared (IR) observations…