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相关论文: Local AGN Survey (LASr): I. Galaxy sample, infrare…

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We use the INTEGRAL all-sky hard X-ray survey to perform a statistical study of a representative sample of nearby AGN. Our entire all-sky sample consists of 127 AGN, of which 91 are confidently detected (>5 sigma) on the time-averaged map…

天体物理学 · 物理学 2016-08-30 S. Sazonov , M. Revnivtsev , R. Krivonos , E. Churazov , R. Sunyaev

Surveys above 10 keV represent one of the the best resources to provide an unbiased census of the population of Active Galactic Nuclei (AGN). We present the results of 60 months of observation of the hard X-ray sky with Swift/BAT. In this…

宇宙学与河外天体物理 · 物理学 2015-06-04 M. Ajello , D. M. Alexander , J. Greiner , G. M. Madejski , N. Gehrels , D. Burlon

X-ray surveys provide the most efficient means for the detection of Active Galactic Nuclei (AGN). However, they face difficulties in detecting the most heavily obscured Compton-thick AGN. The BAT detector on board the Gehrels/Swift mission,…

星系天体物理 · 物理学 2024-12-25 A. Akylas , I. Georgantopoulos , P. Gandhi , P. Boorman , C. L. Greenwell

Heavily obscured accretion is believed to represent an important stage in the growth of supermassive black holes, and to play an important role in shaping the observed spectrum of the Cosmic X-ray Background (CXB). Hard X-ray (E$>$10 keV)…

高能天体物理现象 · 物理学 2017-03-29 C. Ricci , Y. Ueda , M. J. Koss , B. Trakhtenbrot , F. E. Bauer , P. Gandhi

Using a suite of X-ray, mid-IR and optical active galactic nuclei (AGN) luminosity indicators, we search for Compton-thick (CT) AGNs with intrinsic L_X>10^42erg/s at z~0.03-0.2, a region of parameter space which is currently poorly…

宇宙学与河外天体物理 · 物理学 2015-05-20 Andy Goulding , David Alexander , James Mullaney , Jonathan Gelbord , Ryan Hickox , Martin Ward , Mike Watson

We present the first catalog and data release of the Swift-BAT AGN Spectroscopic Survey (BASS). We analyze optical spectra of the majority of AGN (77%, 641/836) detected based on their 14-195 keV emission in the 70-month Swift BAT all-sky…

We combine data from two all-sky surveys in order to study the connection between the infrared and hard X-ray (>10keV) properties for local active galactic nuclei (AGN). The Swift/Burst Alert Telescope all-sky survey provides an unbiased,…

I present a review of X-ray and mid-IR surveys for Compton-thick Active Galactic Nuclei (AGN). These are the most highly obscured sources having hydrogen column densities >1.5x10^24 cm-2. Key surveys in the local Universe are presented…

宇宙学与河外天体物理 · 物理学 2015-06-04 I. Georgantopoulos

We constrain the number density and evolution of Compton-thick Active Galactic Nuclei (AGN). In the local Universe we use the wide area surveys from the Swift and INTEGRAL satellites, while for high redshifts we explore candidate selections…

宇宙学与河外天体物理 · 物理学 2014-11-18 E. Treister , C. Megan Urry , Shanil Virani

We present a new efficient diagnostic method, based on mid-infrared and X-ray data, to select local (z<0.1) Compton-thick (CT) AGN with the aim of estimating their surface and space density. We define a region in the X-ray/IR vs. HR plane…

宇宙学与河外天体物理 · 物理学 2015-06-04 P. Severgnini , A. Caccianiga , R. Della Ceca

We present the results of a program of optical and near-infrared spectroscopic follow-up of candidate Active Galactic Nuclei (AGN) selected in the mid-infrared. This survey selects both normal and obscured AGN closely matched in luminosity…

宇宙学与河外天体物理 · 物理学 2015-06-16 M. Lacy , S. E. Ridgway , E. L. Gates , D. M. Nielsen , A. O. Petric , A. Sajina , T. Urrutia , S. Cox Drews , C. Harrison , N. Seymour , L. J. Storrie-Lombardi

We quantify the active galactic nucleus (AGN) contribution to the mid-infrared (mid-IR) and the total infrared (IR, 8-1000micron) emission in a complete volume-limited sample of 53 local luminous infrared galaxies (LIRGs). We decompose the…

宇宙学与河外天体物理 · 物理学 2012-05-16 Almudena Alonso-Herrero , Miguel Pereira-Santaella , George H. Rieke , Dimitra Rigopoulou

We present a new method to predict the line-of-sight column density (NH) values of active galactic nuclei (AGN) based on mid-infrared (MIR), soft, and hard X-ray data. We developed a multiple linear regression machine learning algorithm…

We constrain the number density and evolution of Compton-thick Active Galactic Nuclei (AGN), and their contribution to the extragalactic X-ray background. In the local Universe we use the wide area surveys from the Swift and INTEGRAL…

宇宙学与河外天体物理 · 物理学 2015-05-14 E. Treister , C. M. Urry , C. Cardamone , S. Virani , K. Schawinski , E. Gawiser

Searching for active galactic nuclei (AGN) in dwarf galaxies is important for our understanding of the seed black holes that formed in the early Universe. Here, we test infrared selection methods for AGN activity at low galaxy masses. Our…

星系天体物理 · 物理学 2016-12-07 Kevin N. Hainline , Amy E. Reines , Jenny E. Greene , Daniel Stern

We present a census of local active galactic nuclei (AGN) at a redshift of $z\leq0.025$ selected using the high-ionization [Ne v] $\lambda14.32\,\mu$m emission line from the Infrared Database of Extragalactic Observables from Spitzer…

星系天体物理 · 物理学 2026-03-16 S. Yassir , A. Annuar

The Swift AGN and Cluster Survey (SACS) uses 125 deg^2 of Swift XRT serendipitous fields with variable depths surrounding gamma-ray bursts to provide a medium depth (4e-15 erg/s/cm^2) and area survey filling the gap between deep, narrow…

宇宙学与河外天体物理 · 物理学 2015-05-27 Xinyu Dai , Rhiannon D. Griffin , Christopher S. Kochanek , Jenna M. Nugent , Joel N. Bregman

Even in deep X-ray surveys, Compton-thick active galactic nuclei (CT AGNs, ${\rm N_H} \geqslant 1.5~\times~10^{24}~{\rm cm}^{-2}$) are difficult to be identified due to X-ray flux suppression and their complex spectral shape. However, the…

星系天体物理 · 物理学 2021-03-03 Xiaotong Guo , Qiusheng Gu , Nan Ding , Xiaoling Yu , Yongyun Chen

The Compton-thick Active Galactic Nuclei (AGN) arguably constitute the most elusive class of sources as they are absorbed by large column densities above logN_H(cm^-2)=24. These extreme absorptions hamper the detection of the central source…

星系天体物理 · 物理学 2025-03-12 I. Georgantopoulos , E. Pouliasis , A. Ruiz , A. Akylas

We have developed an efficient Active Galactic Nucleus (AGN) selection method using 18-band Spectral Energy Distribution (SED) fitting in mid-infrared (mid-IR). AGNs are often obscured by gas and dust, and those obscured AGNs tend to be…

星系天体物理 · 物理学 2017-08-29 Ting-Chi Huang , Tomotsugu Goto , Tetsuya Hashimoto , Nagisa Oi , Hideo Matsuhara
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