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Related papers: The X-ray coronae in NuSTAR bright active galactic…

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We present initial results and the source catalog from the NuSTAR survey of the Extended Chandra Deep Field South (hereafter, ECDFS) - currently the deepest contiguous component of the NuSTAR extragalactic survey program. The survey covers…

[Abridged] The X-ray broadband spectra of the bare AGN Mrk 110, obtained by simultaneous XMM-Newton and NuSTAR observations (Nov 2019 and April 2020), are characterised by the presence of a prominent and absorption-free smooth soft X-ray…

High Energy Astrophysical Phenomena · Physics 2023-10-24 Delphine Porquet , Scott Hagen , Nicolas Grosso , Andrew Lobban , James N. Reeves , Valentina Braito , Chris Done

We report preliminary results from an arcsecond-resolution X-ray survey of nearby galaxies using ACIS on board Chandra. The total sample consists of 41 low-luminosity AGNs, including Seyferts, LINERs, and LINER/H II transition objects. In…

We present the results from an X-ray spectral analysis of active galactic nuclei (AGN) in the Chandra Deep Field-South, AEGIS-XD and Chandra-COSMOS surveys, focussing on the identification and characterisation of the most heavily obscured,…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Murray Brightman , Kirpal Nandra , Mara Salvato , Li-Ting Hsu , Cyprian Rangel

We undertake a spectral study of a sample of bright X-ray sources taken from six XMM-Newton fields at high galactic latitudes, where AGN are the most populous class. These six fields were chosen such that the observation had an exposure…

High Energy Astrophysical Phenomena · Physics 2015-05-30 M. A. Hassan , B. A. Korany , R. Misra , I. A. M. Issa , M. K. Ahmed , F. A. Abdel-Salam

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,…

High Energy Astrophysical Phenomena · Physics 2018-03-28 P. O. Petrucci , F. Ursini , A. De Rosa , S. Bianchi , M. Cappi , G. Matt , M. Dadina , J. Malzac

We present the first broad-band X-ray study of the nuclei of 14 hard X-ray selected giant radio galaxies, based both on the literature and on the analysis of archival X-ray data from NuSTAR, XMM-Newton, Swift and INTEGRAL. The X-ray…

High Energy Astrophysical Phenomena · Physics 2018-09-26 F. Ursini , L. Bassani , F. Panessa , A. J. Bird , G. Bruni , M. Fiocchi , A. Malizia , L. Saripalli , P. Ubertini

We perform long-term ($\approx 15$ yr, observed-frame) X-ray variability analyses of the 68 brightest radio-quiet active galactic nuclei (AGNs) in the 6 Ms $Chandra$ Deep Field-South (CDF-S) survey; the majority are in the redshift range of…

High Energy Astrophysical Phenomena · Physics 2016-11-09 G. Yang , W. Brandt , B. Luo , Y. Xue , F. Bauer , M. Sun , S. Kim , S. Schulze , X. Zheng , M. Paolillo , O. Shemmer , T. Liu , D. Schneider , C. Vignali , F. Vito , J. -X. Wang

The SWIFT gamma ray observatory's Burst Alert Telescope (BAT) has detected a sample of active galactic nuclei (AGN) based solely on their hard X-ray flux (14-195 keV). In this paper, we present for the first time {\it XMM-Newton} X-ray…

Astrophysics · Physics 2009-11-13 Lisa M. Winter , Richard F. Mushotzky , Jack Tueller , Craig Markwardt

Warm coronae, thick ($\tau_{\mathrm{T}}\approx 10$-$20$, where $\tau_{\mathrm{T}}$ is the Thomson depth) Comptonizing regions with temperatures of $\sim 1$ keV, are proposed to exist at the surfaces of accretion discs in active galactic…

High Energy Astrophysical Phenomena · Physics 2020-07-08 D. R. Ballantyne , X. Xiang

We searched for thermal gyro-synchrotron radio emission from a sample of five radio-loud stars whose X-ray coronae contain a hot ($T_e>10^7$ K) thermal component. We used the JVLA to measure Stokes I and V/I spectral energy distributions…

Solar and Stellar Astrophysics · Physics 2024-01-08 Walter W. Golay , Robert L. Mutel , Dani Lipman , Manuel Güdel

Radio-loud active galactic nuclei (AGN) are among the most luminous objects in the Universe, emitting radiation from low-energy radio waves to high energy $\gamma$-rays. They are well known to exhibit flux variations at nearly all…

Astrophysics of Galaxies · Physics 2026-03-19 M. Reshma , C. S. Stalin , Amit Kumar Mandal , S. B. Gudennavar , Senorita Benedict , Prajwel Joseph

We investigate the 1.4 GHz radio properties of 92 nearby (z<0.05) ultra hard X-ray selected Active Galactic Nuclei (AGN) from the Swift Burst Alert Telescope (BAT) sample. Through the ultra hard X-ray selection we minimise the biases…

Astrophysics of Galaxies · Physics 2016-05-04 O. Ivy Wong , M. J. Koss , K. Schawinski , A. D. Kapińska , I. Lamperti , K. Oh , C. Ricci , S. Berney

We present a systematic investigation of X-ray thermal coronae in 157 early-type galaxies and 22 late-type galaxies from a survey of 25 hot (kT>3 keV), nearby (z<0.05) clusters, based on CHANDRA archival data. Cool galactic coronae…

Astrophysics · Physics 2008-11-26 M. Sun , C. Jones , W. Forman , A. Vikhlinin , M. Donahue , M. Voit

We compile a sample consisting of 56 radio-quiet active galactic nuclei so as to investigate statistical properties of hot corona of accretion disks from {\em ASCA} observations. The black-hole masses in the sample are estimated via several…

Astrophysics · Physics 2009-11-10 Jian-Min Wang , Ken-Ya Watarai , Shin Mineshige

Using long-term monitoring data from the Rossi X-ray Timing Explorer (RXTE), we have selected 23 active galactic nuclei (AGN) with sufficient brightness and overall observation time to derive broadband X-ray spectra from 3 to >100 keV. Our…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Elizabeth Rivers , Alex Markowitz , Richard Rothschild

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…

Astrophysics · Physics 2009-11-13 J. Fritz , A. Franceschini , E. Hatziminaoglou

In the X-ray spectra of AGNs, a noticeable excess of soft X-rays is typically detected beyond the extrapolation of the power-law trend observed between 2-10 keV. In the scenario of warm Comptonization, observations propose a warm corona…

High Energy Astrophysical Phenomena · Physics 2024-09-18 B. Palit , A. Rozanska , P. O. Petrucci , D. Gronkiewicz , S. Barnier , S. Bianchi , D. R. Ballantyne , V. E. Gianolli , R. Middei , R. Belmont , F. Ursini

In this concluding part of the series of three papers dedicated to the Swift/BAT hard X-ray survey (BXS), we focus on the X-ray spectral analysis and statistical properties of the source sample. Using a dedicated method to extract…