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Related papers: The hard X-ray perspective on the soft X-ray exces…

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An excess of X-ray emission below 1 keV, called soft excess, is detected in a large fraction of Seyfert 1-1.5s. The origin of this feature remains debated, as several models have been suggested to explain it, including warm Comptonization…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Rozenn Boissay , Claudio Ricci , Stéphane Paltani

XMM-Newton and NuSTAR multiple exposures allow us to disentangle the different emission components of active galactic nuclei (AGNs) and to study the evolution of their different spectral features. In this work, we present the timing and…

High Energy Astrophysical Phenomena · Physics 2020-10-07 R. Middei , P. -O. Petrucci , S. Bianchi , F. Ursini , M. Cappi , M. Clavel , A. De Rosa , A. Marinucci , G. Matt , A. Tortosa

We have observed with XMM-Newton four radiatively efficient active type 1 galaxies with black hole masses < 10^6 Msun, selected optically from the SDSS. We show here that their soft X-ray spectrum exhibits a soft excess with the same…

Astrophysics · Physics 2009-11-13 G. Miniutti , G. Ponti , J. E. Greene , L. C. Ho , A. C. Fabian , K. Iwasawa

The soft X-ray excess - the excess of X-rays below 2 keV with respect to the extrapolation of the hard X-ray spectral continuum model - is a very common feature among type 1 active galactic nuclei (AGN); yet the nature of the soft X-ray…

High Energy Astrophysical Phenomena · Physics 2020-01-08 M. Gliozzi , J. K. Williams

Active Galactic Nuclei (AGN) are the most luminous persistent objects in the universe. An excess of X-ray emission below about 2 keV, called soft-excess, is very common in Type 1 AGN spectra. The origin of this feature remains debated.…

The nature and origin of the soft X-ray excess in radio quiet AGN is still an open issue. The interpretation in terms of thermal disc emission has been challanged by the discovery of the constancy of the effective temperature despite the…

Astrophysics · Physics 2009-11-13 F. D'Ammando , S. Bianchi , E. Jimenez-Bailon , G. Matt

(Abridged) Soft and hard X-ray excesses, compared to the continuum power-law shape between ~2-10 keV, are common features observed in the spectra of active galactic nuclei (AGN) and are associated with the accretion disc-corona system…

High Energy Astrophysical Phenomena · Physics 2021-10-20 D. Porquet , J. N. Reeves , N. Grosso , V. Braito , A. Lobban

The X-ray emission from active galactic nuclei (AGN) is believed to come from a combination of inverse Compton scattering of photons from the accretion disk and reprocessing of the direct X-ray emission by reflection. We present hard (10-80…

High Energy Astrophysical Phenomena · Physics 2023-12-01 Cora A. DeFrancesco , Xinyu Dai , Mark Mitchell , Abderahmen Zoghbi , Christopher W. Morgan

The UV to X-ray continuum of active galactic nuclei (AGN) is important for maintaining the ionisation and thermal balance of the warm absorbers (WAs). However, the spectra in the sensitive energy range $\sim \,13.6 -300 \ev$ are…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Sibasish Laha , Gulab C. Dewangan , Susmita Chakravorty , Ajit K. Kembhavi

We investigate the nature of the soft excess below 1 keV observed in AGN. We use the XMM-Newton data of the low redshift, optically bright quasar, PG 1211+143, and we compare it with the Narrow Line Seyfert 1 galaxy, 1H 0707-495, which has…

Astrophysics · Physics 2008-11-26 Malgorzata A. Sobolewska , Chris Done

We investigate the nature of the soft excess below 1 keV observed in AGN. We use the XMM-Newton data of the low redshift, optically bright quasar, PG 1211+143, and we compare it with the Narrow Line Seyfert 1 galaxy, 1H 0707-495, which has…

Astrophysics · Physics 2016-08-30 Malgorzata Sobolewska , Chris Done

We present a detailed spectral analysis of the joint XMM-Newton and NuSTAR observations of the active galactic nuclei (AGN) in the Seyfert 1.5 Galaxy ESO 362-G18. The broadband ($0.3\mbox{--}79$ keV) spectrum shows the presence of a…

High Energy Astrophysical Phenomena · Physics 2021-05-20 Yerong Xu , Javier A. García , Dominic J. Walton , Riley M. T. Connors , Kristin Madsen , Fiona A. Harrison

Above $\sim$3 keV, the X-ray spectrum of the active galactic nuclei (AGN) is characterized by the intrinsic continuum and compton reflection features. For type-1 AGN, several regions could contribute to the reflection. In order to…

A core sample of 59 unobscured type 1 AGNs with simultaneous XMM-Newton X-ray and UV observations is compiled from archive to probe the nature of soft X-ray excess (SE). In the first paper of this series, our focus centers on scrutinizing…

High Energy Astrophysical Phenomena · Physics 2025-03-17 Shi-Jiang Chen , Jun-Xian Wang , Jia-Lai Kang , Wen-Yong Kang , Hao Sou , Teng Liu , Zhen-Yi Cai , Zhen-Bo Su

The 2-10 keV continuum of AGN is well represented by a single power law, generally attributed to a hot comptonizing medium, such as a corona above the accretion disk. At smaller energies the continuum displays an excess with respect to the…

We present results of a high-resolution soft X-ray (0.2-2 keV) spectroscopic study of a sample of 69 nearby obscured Active Galactic Nuclei (AGN) observed with the Reflection Grating Spectrometer (RGS) on board XMM-Newton. This is the…

Astrophysics · Physics 2008-11-26 Matteo Guainazzi , Stefano Bianchi

The X-ray spectra of active galactic nuclei (AGNs) often exhibit an excess of emission above the primary power-law at energies <~ $2$ keV. Two models for the origin of this `soft excess' are ionized relativistic reflection from the inner…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Xin Xiang , D. R. Ballantyne , S. Bianchi , A. De Rosa , G. Matt , R. Middei , P. -O. Petrucci , A. Rozanska , F. Ursini

Probing the physics of the accretion flow around active galactic nuclei (AGN) is crucial to understanding their emission mechanisms as well as being able to constrain the geometrical and variability properties of the different regions…

High Energy Astrophysical Phenomena · Physics 2022-06-01 Oluwashina K. Adegoke

We perform an X-ray spectral analysis of the brightest and cleanest bare AGN known so far, Ark 120, in order to determine the process(es) at work in the vicinity of the SMBH. We present spectral analysis of data from an extensive campaign…

We present simultaneous XMM-Newton and NuSTAR observations of the `bare' Seyfert 1 galaxy, Ark 120, a system in which ionized absorption is absent. The NuSTAR hard X-ray spectral coverage allows us to constrain different models for the…

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