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We analyze recent simultaneous Chandra/RXTE observations of the Seyfert 2 galaxy NGC 4945. The unprecedented spatial resolution of Chandra means we are able to separate the spectra of the nucleus, starburst and superwind regions, while the…

Astrophysics · Physics 2009-11-07 Chris Done , Greg M. Madejski , Piotr T. Zycki , Lincoln J. Greenhill

Obscured AGN are fundamental to understand the history of Super Massive Black Hole growth and their influence on galaxy formation. However, the Compton-thick AGN (NH>1e24 cm^-2) population is basically unconstrained, with less than few…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 P. Severgnini , A. Caccianiga , R. Della Ceca , V. Braito , C. Vignali , V. La Parola , A. Moretti

We have carried out an extensive X-ray spectral study of the bare Seyfert-1 galaxy MCG--02--58--22 to ascertain the nature of the X-ray reprocessing media, using observations from Suzaku (2009) and simultaneous observations from XMM-Newton…

High Energy Astrophysical Phenomena · Physics 2021-07-21 Sibasish Laha , Ritesh Ghosh

We present a NuSTAR and XMM-Newton monitoring campaign in 2014/2015 of the Compton-thick Seyfert 2 galaxy, NGC 1068. During the August 2014 observation, we detect with NuSTAR a flux excess above 20 keV ($32\pm6 \%$) with respect to the…

We have used X-ray spectra to measure attenuating columns in a large sample of Seyfert galaxies. Over 30 of these sources have resolved radio jets, allowing the relative orientation of the nucleus and host galaxy to be constrained. We have…

Astrophysics · Physics 2017-08-23 Jonathan Gelbord , K. A. Weaver , T. Yaqoob

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 present the results of a BeppoSAX observation of the nearby spiral galaxy NGC4945 in the 0.1-200 keV energy band. The nuclear X-ray emission emerges above ~7 keV, through an absorber with column density N_H ~ a few 10^24/cm/cm. Its…

Astrophysics · Physics 2009-09-25 M. Guainazzi , G. Matt , W. N. Brandt , L. A. Antonelli , P. Barr , L. Bassani

We investigate the X-ray spectrum of the Seyfert galaxy NGC 4151 using the simultaneous Suzaku/NuSTAR observation and flux-resolved INTEGRAL spectra supplemented by Suzaku and XMM observations. Our best spectral solution indicates that the…

High Energy Astrophysical Phenomena · Physics 2021-03-24 Michal Szanecki , Andrzej Niedzwiecki , Andrzej A. Zdziarski

We present XMM-Newton spectral analysis of all 38 Seyfert galaxies from the Palomar spectroscopic sample of galaxies. These are found at distances of up to 67 Mpc and cover the absorbed 2-10 keV luminosity range ~10^38-10^43 ergs/s. Our aim…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. Akylas , I. Georgantopoulos

An extended XMM-Newton observation of the Seyfert 1 galaxy NGC 4051 has revealed a rich absorption line spectrum indicating the presence of a photoionized outflow with a wide range of velocities and ionization parameter. At low continuum…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 K. A. Pounds , S. Vaughan

We present a sample of 17 type 2 Seyfert galaxies which have an X-ray column density lower than 10^{22} cm^{-2}. The Compton thin nature of these sources is strongly suggested by isotropic indicators. We estimate the fraction of these…

Astrophysics · Physics 2009-11-07 Francesca Panessa , Loredana Bassani

Variability across the electromagnetic spectrum is a property of AGN that can help constraining the physical properties of these galaxies. This is the third of a serie of papers with the aim of studying the X-ray variability of different…

Astrophysics of Galaxies · Physics 2015-07-08 L. Hernández-García , J. Masegosa , O. González-Martín , I. Márquez

Through an optical campaign performed at 5 telescopes located in the northern and the southern hemispheres, plus archival data from two on line sky surveys, we have obtained optical spectroscopy for 17 counterparts of suspected or poorly…

The presence of an obscuring torus around the nucleus of Seyfert galaxies, as supposed in the popular unification scheme, can strongly modify the X--ray spectrum for both type 1 and 2 Seyfert galaxies. We find that if the torus is Compton…

Astrophysics · Physics 2015-06-24 Gabriele Ghisellini , Francesco Haardt , Giorgio Matt

We present a broadband (~0.5-79 keV) spectral and temporal analysis of multiple NuSTAR observations combined with archival Suzaku and Chandra data of NGC4945, the brightest extragalactic source at 100 keV. We observe hard X-ray (> 10 keV)…

We present mid infrared (Mid-IR) spectra of the Compton-thick Seyfert 2 galaxy NGC\,3281, obtained with the Thermal-Region Camera Spectrograph (T-ReCS) at the Gemini South telescope. The spectra present a very deep silicate absorption at…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Dinalva A. Sales , M. G. Pastoriza , R. Riffel , C. Winge , A. Rodriguez-Ardila , A. C. Carciofi

We have made BeppoSAX observations of the Seyfert 2/1.9 galaxy ESO103-G35, which contains a nuclear maser source and is known to be heavily absorbed in the X-rays. Analysis of the X-ray spectra observed by SAX in October 1996 and 1997…

In this paper we discuss the X-ray properties of 49 local (z<0.035) Seyfert 2 galaxies with HST/WFC2 high-resolution optical coverage. It includes the results of 26 still unpublished Chandra and XMM-Newton observations, which yield 25 (22)…

Astrophysics · Physics 2009-11-11 M. Guainazzi , G. Matt , G. C. Perola

Unified models of Seyfert galaxies, based on viewing angles, successfully explain the observed differences between type 1 and 2 Seyferts. The existence of a range in accretion rates relative to the Eddington rate (from broad-line Seyfert 1s…

Astrophysics · Physics 2009-11-11 G. C. Dewangan , R. E. Griffiths

We present a long (~76 ks) Chandra observation of IRAS 09104+4109, a hyper-luminous galaxy, optically classified as a Type 2 AGN hosted in a cD galaxy in a cluster at z=0.442. We also report on the results obtained by fitting its broad-band…

High Energy Astrophysical Phenomena · Physics 2015-05-28 C. Vignali , E. Piconcelli , G. Lanzuisi , A. Feltre , C. Feruglio , R. Maiolino , F. Fiore , J. Fritz , V. La Parola , M. Mignoli , F. Pozzi
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