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相关论文: A receding torus model for the Iwasawa-Taniguchi e…

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We present X-ray spectral analysis of the brightest sources (f_{2-10 keV}>10^{-15}$ cgs) in the Chandra Deep Field North. Our sample consists of 222 sources; for the vast majority (171) either a spectroscopic or a photometric redshift is…

宇宙学与河外天体物理 · 物理学 2009-09-02 I. Georgantopoulos , A. Akylas , A. Georgakakis , M. Rowan-Robinson

We present X-ray bolometric correction factors, $\kappa_{Bol}$ ($\equiv L_{Bol}/L_X$), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric…

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…

天体物理学 · 物理学 2009-11-13 J. Fritz , A. Franceschini , E. Hatziminaoglou

We utilize mid-infrared multi-epoch data from Wide-field Infrared Survey Explorer (WISE) over a $\sim10$-year period in W1 (3.4$\mu$m) and W2 (4.6$\mu$m) bands to investigate the structure of dusty torus in low-redshift ($0.15<z\le 0.4$)…

星系天体物理 · 物理学 2022-03-14 Suyeon Son , Minjin Kim , Luis C. Ho

Chandra and XMM-Newton have resolved the 2-8 keV X-ray Background (XRB) into point sources. Many of the fainter sources are obscured active galactic nuclei (AGN) with column densities in the range of 10^22-10^23 pcmsq, some of which have…

天体物理学 · 物理学 2009-11-07 A. C. Fabian , R. J. Wilman , C. S. Crawford

The central engines of both type 1 and type 2 AGNs are thought to harbor a toroidal structure that absorbs and reprocesses high-energy photons from the central X-ray source. If the reprocessor is Compton-thick, the calculation of…

高能天体物理现象 · 物理学 2015-05-13 K. D. Murphy , T. Yaqoob

We argue that the X-ray and UV flux illuminating the parsec-scale accretion disk around luminous active galactic nuclei (AGN) is super-Eddington with respect to the local far-infrared dust opacity. The far infrared opacity may be larger…

天体物理学 · 物理学 2011-02-11 P. Chang , E. Quataert , N. Murray

Broad relativistic iron lines from neutron star X-ray binaries are important probes of the inner accretion disk. The X-ray reflection features can be weakened due to strong magnetic fields or very low iron abundances such as is possible in…

高能天体物理现象 · 物理学 2016-07-27 Aditya S. Mondal , Gulab C. Dewangan , Mayukh Pahari , Ranjeev Misra , Ajit K. Kembhavi , Biplab Raychaudhuri

The Swift/BAT nine-month survey observed 153 AGN, all with ultra-hard X-ray BAT fluxes in excess of 10^-11 erg cm^-2 s^-1 and an average redshift of 0.03. Among them, four of the most luminous BAT AGN (44.73 < Log L(BAT) < 45.31) were…

高能天体物理现象 · 物理学 2015-06-15 V. Fioretti , L. Angelini , R. F. Mushotzky , M. Koss , G. Malaguti

We report a new analysis of ASCA data on the iron K line complex in NGC1068. The line complex basically consists of three components, as previously reported. A weak red wing of the 6.4 keV fluoresence iron K line is found. A plausible…

天体物理学 · 物理学 2015-06-24 K. Iwasawa , A. C. Fabian , G. Matt

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…

Average hard-tail X-ray emission in the soft state of nine bright Atoll low-mass X-ray binaries containing a neutron star (NS-LMXBs) are investigated by using the light curves of MAXI/GSC and Swift/BAT. Two sources (4U 1820$-$30 and 4U…

高能天体物理现象 · 物理学 2016-04-18 Kazumi Asai , Tatehiro Mihara , Masaru Mastuoka , Mutsumi Sugizaki

Unified X-ray spectral and timing studies of Cygnus X-1 in the low/hard and hard intermediate state were conducted in a model-independent manner, using broadband Suzaku data acquired on 25 occasions from 2005 to 2009 with a total exposure…

高能天体物理现象 · 物理学 2015-06-15 Shin'ya Yamada , Kazuo Makishima , Chris Done , Shunsuke Torii , Hirofumi Noda , Soki Sakurai

As the mid-IR luminosity represents a good isotropic proxy of the AGN power, a low X-ray to mid-IR luminosity ratio is often claimed to be a reliable indicator for selecting Compton-thick (CT) AGN. We assess the efficiency of this…

宇宙学与河外天体物理 · 物理学 2015-05-28 I. Georgantopoulos , E. Rovilos , A. Akylas , A. Comastri , P. Ranalli , C. Vignali , I. Balestra , R. Gilli , N. Cappelluti

Type-I X-ray bursts on the surface of a neutron star are a unique probe to the accretion in X-ray binary systems. However, we know little about the feedback of the burst emission upon accretion. Hard X-ray shortages and enhancements of the…

高能天体物理现象 · 物理学 2015-06-17 Long Ji , Shu Zhang , YuPeng Chen , Shuang-Nan Zhang , Diego F. Torres , Peter Kretschmar , Erik Kuulkers , Jian Li , Zhi Chang

The absence of intrinsic broad line emission has been reported in a number of active galactic nuclei (AGN), including some with high Eddington ratios. Such "true type 2 AGN" are inherent to the disk-wind scenario for the broad line region:…

星系天体物理 · 物理学 2016-04-27 Moshe Elitzur , Hagai Netzer

Heavily obscured, Compton Thick (CT, NH>10^24 cm^-2) AGN may represent an important phase in AGN/galaxy co-evolution and are expected to provide a significant contribution to the cosmic X-ray background (CXB). Through direct X-ray spectra…

A large population of heavily obscured, Compton Thick AGNs is predicted by models of galaxy formation, models of Cosmic X-ray Background and by the ``relic'' super-massive black-hole mass function measured from local bulges. However, so far…

The X-ray spectra of many active galactic nuclei (AGN) show a soft X-ray excess below 1-2 keV on top of the extrapolated high- energy power law. The origin of this component is uncertain. It could be a signature of relativistically blurred,…

高能天体物理现象 · 物理学 2018-03-28 P. O. Petrucci , F. Ursini , A. De Rosa , S. Bianchi , M. Cappi , G. Matt , M. Dadina , J. Malzac

Near-Eddington radiation from active galactic nuclei (AGNs) has significant dynamical influence on the surrounding dusty gas, plausibly furnishing AGNs with geometrically thick obscuration. We investigate this paradigm with radiative…

星系天体物理 · 物理学 2017-08-21 Chi-Ho Chan , Julian H. Krolik