相关论文: An X-ray spectral model for clumpy tori in active …

According to recent models, the accretion disk and black hole in active galactic nuclei are surrounded by a clumpy torus. We investigate the NIR flux variation of the torus in response to a UV flash for various geometries. Anisotropic…

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…

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…

Variable X-ray absorption has been observed in active galactic nuclei (AGN) on several time scales. Observations allow us to identify the absorber with clouds associated either with the clumpy torus (parsec scales, long timescales) or with…

We report results from multi-epoch X-ray observations of the polar-scattered Seyfert 1 galaxy ESO 323-G77. The source exhibits remarkable spectral variability from months to years timescales. The observed spectral variability is entirely…

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…

This work discusses the broadband X-ray spectral analysis of 11 candidate heavily-obscured active galactic nuclei (AGN) selected based on their infrared and X-ray properties by a recently published machine learning algorithm. This paper is…

Unified schemes of active galactic nuclei (AGN) require an obscuring dusty torus around the central engine. The compact sizes (only a few pc) determined in recent high-resolution observations require that the obscuring matter be clumpy and…

We describe improved modelling of the emission by dust in a toroidal--like structure heated by a central illuminating source within Active Galactic Nuclei (AGN). We chose a simple but realistic torus geometry, a flared disc, and a dust…

Using a complete, magnitude-limited sample of active galaxies from the Sloan Digital Sky Survey (SDSS) we show that the fraction of broad-line (Type 1) active galactic nuclei increases with luminosity of the isotropically-emitted [O III]…

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…

Heavily obscured Active Galactic Nuclei (AGN), especially Compton-thick sources with line-of-sight column density ($N_{\rm H,los}$) $>$ 10$^{24}$ cm$^{-2}$, are critical to understanding supermassive black hole (SMBH) growth and the origin…

A joint XMM-Newton and NuSTAR observation was conducted for the bright, local Seyfert 1.9 galaxy, NGC 1194. The hard spectral form of this AGN was modeled using the toroidal reprocessor MYTORUS. The decoupled model form provides a good…

We combine near-to-mid-IR Spitzer data with shorter wavelength observations (optical to X-rays) to get insights on the properties of a sample of luminous, obscured Active Galactic Nuclei (AGN). We aim at modeling their broad-band Spectral…

We construct the rest-frame 2--10 keV intrinsic X-ray luminosity function of Active Galactic Nuclei (AGNs) from a combination of X-ray surveys from the all-sky Swift BAT survey to the Chandra Deep Field-South. We use ~3200 AGNs in our…

In this paper we report the results of an X-ray monitoring campaign on the heavily obscured Seyfert galaxy Markarian 3 carried out between the fall of 2014 and the spring of 2015 with NuSTAR, Suzaku and XMM-Newton. The hard X-ray spectrum…

Radio galaxies are a key population to understand the importance of relativistic jets in AGN feedback. We present the results of a systematic, broadband X-ray spectral analysis of hard X-ray selected radio galaxies to investigate their…

We suggest a method for probing global properties of clump populations in Giant Molecular Clouds (GMCs) in the case where these act as X-ray reflection nebulae (XRNe), based on the study of the clumping's overall effect on the reflected…

We present new estimates on the fraction of heavily X-ray obscured, Compton-thick (CT) active galactic nuclei (AGNs) out to a redshift of $z \leq$ 0.8. From a sample of 540 AGNs selected by mid-IR (MIR) properties in observed X-ray survey…

An integral part of the Unified Model for Active Galactic Nuclei (AGNs) is an axisymmetric obscuring medium, which is commonly depicted as a torus of gas and dust surrounding the central engine. However, a robust, dynamical model of the…