Related papers: A multiwavelength-motivated X-ray model for the Ci…
We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection…
We present an HST imaging study of the nearby (4 Mpc distant) Circinus galaxy, which contains the nearest type 2 Seyfert nucleus and prominent circumnuclear star formation. Images have been obtained in the [OIII]$\lambda$5007, H$\alpha$ and…
Obscuration of the innermost parts of active galactic nuclei (AGN) is observed in the majority of the population both in the nearby universe and at high redshift. However, the nature of the structures causing obscuration, especially in…
The nature of the putative torus and the outer geometry of active galactic nuclei (AGN) are still rather unknown and the subject of active research. Improving our understanding of them is crucial for developing a physical picture for the…
We present X-ray spectra of four ultraluminous infrared galaxies (ULIRGs) with detectable broad near-infrared emission lines produced by active galactic nuclei (AGNs): Mrk 463, PKS 1345+12, IRAS 05189-2524, and IRAS 07598+6508. With the…
We have incorporated the description of the X-ray properties of Active Galactic Nuclei (AGNs) into a semi-analytic model of galaxy formation, adopting physically motivated scaling laws for accretion triggered by galaxy encounters. Our model…
We present the broad-band X-ray spectral analysis (0.6-50 keV) of seven Compton-Thick active galactic nuclei (CT-AGN; line-of-sight, l.o.s., column density $>10^{24}$ cm$^{-2}$) candidates selected from the Swift-BAT 100-month catalog,…
We present the systematic broadband X-ray spectral analysis of 52 Compton-thick ($24 \leq \log N_{\mathrm{H}}^{\mathrm{LOS}}/\mathrm{cm}^{-2}$) active galactic nucleus (CTAGN) candidates selected by the Swift/BAT all-sky hard X-ray survey…
We performed near-diffraction-limited (~0.4 FWHM) N-band imaging of one of the nearest Active Galactic Nucleus (AGN) in M51 with 8.2m Subaru telescope to study the nuclear structure and spectral energy distribution (SED) at 8-13 um. We…
Reprocessed X-ray radiation carries important information about the structure and physical characteristics of the material surrounding the supermassive black hole (SMBH) in active galactic nuclei (AGN). We report here on a newly developed…
The covering factor of Compton-thick obscuring material associated with the torus in active galactic nuclei (AGN) is at present best understood through the fraction of sources exhibiting Compton-thick absorption along the line of sight…
A significant number of active galactic nuclei (AGNs) are observed to be hidden behind dust and gas. The distribution of material around AGNs plays an important role in modeling the cosmic X-ray background (CXB), especially the fraction of…
AGN are known to have complex X-ray spectra that depend on both the properties of the accreting SMBH (e.g. mass, accretion rate) and the distribution of obscuring material in its vicinity ("torus"). Often however, simple and even unphysical…
Reprocessed X-ray radiation from active galactic nuclei (AGN) carries important information about the properties of the circumnuclear material around the black hole. The X-ray photons travel from the very center of the system and interact…
We present imaging and spatially resolved spectral analyses of eight Chandra data taken for the Circinus galaxy in $\approx$ 22 years to reveal neutral iron-K$\alpha$ emission on a circumnuclear scale ($\sim$ 10--100 pc) and search for time…
We observed the Galactic black hole Cygnus X-1 with the Chandra High Energy Transmission Grating Spectrometer for 30 kiloseconds on 4 January, 2001. The source was in an intermediate state, with a flux that was approximately twice that…
We report Suzaku observations of the active, Compton-thick Circinus galaxy. Observations were obtained with both the X-ray Imaging spectrometer (XIS) and the Hard X-ray Detector (HXD). Below 10 keV, the nuclear spectrum is dominated by…
In this paper we present the first-ever $L$- and $M$-band interferometric observations of Circinus, building upon a recent $N$-band analysis. We used these observations to reconstruct images and fit Gaussian models to the $L$ and $M$ bands.…
Using the X-ray-selected active galactic nuclei (AGN) from the XMM-XXL north survey and the SDSS Baryon Oscillation Spectroscopic Survey (BOSS) spectroscopic follow-up of them, we compare the properties of X-ray unobscured and obscured…
We analyzed the spectral shape of the Compton shoulder around the neutral Fe-K$_\alpha$ line of the Compton-thick type II Seyfert nucleus of the Circinus galaxy. The characteristics of this Compton shoulder with respect to the reflected…