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Related papers: NGC3147: a "true" Seyfert 2 without the broad-line…

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We study the X-ray spectra of a sample of 19 obscured, optically-selected Seyfert galaxies (Sy 1.8, 1.9 and 2) in the local universe ($d \leq 175$~Mpc), drawn from the CfA Seyfert sample. Our analysis is driven by the high sensitivity of…

High Energy Astrophysical Phenomena · Physics 2020-10-14 E. S. Kammoun , J. M. Miller , M. Koss , K. Oh , A. Zoghbi , R. F. Mushotzky , D. Barret , E. Behar , W. N. Brandt , L. W. Brenneman , J. S. Kaastra , A. M. Lohfink , D. Proga , D. Stern

We present RXTE monitoring observations of the Seyfert 2 galaxy Mrk 348 spanning a 6 month period. The time-averaged spectrum in the 3-20 keV band shows many features characteristic of a Compton-thin Seyfert 2 galaxy, namely a hard…

Astrophysics · Physics 2009-10-31 David A. Smith , Ioannis Georgantopoulos , Robert S. Warwick

Current measurements show that the observed fraction of Compton-thick (CT) AGN is smaller than the expected values needed to explain the cosmic X-ray background. Prior fits to the X-ray spectrum of the nearby Seyfert-2 galaxy NGC 5347…

High Energy Astrophysical Phenomena · Physics 2019-06-05 E. S. Kammoun , J. M. Miller , A. Zoghbi , K. Oh , M. Koss , R. F. Mushotzky , L. W. Brenneman , W. N. Brandt , D. Proga , A. M. Lohfink , J. S. Kaastra , D. Barret , E. Behar , D. Stern

We present ultraviolet spectra of the dwarf Seyfert 1 nucleus of NGC 4395, obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope's Space Telescope Imaging Spectrograph at velocity resolutions of 7 to…

Based on previous spectral and temporal optical studies, Q2122-444 has been classified as a naked AGN or true type 2 AGN, that is, an AGN that genuinely lacks a broad line region (BLR). Its optical spectrum seemed to possess only narrow…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 M. Gliozzi , F. Panessa , F. La Franca , I. Saviane , L. Monaco , L. Foschini , L. Kedziora-Chudczer , S. Satyapal , R. M. Sambruna

(Abridged) We present the results from {\it ASCA} observations of NGC 3227 along with those from a {\it ROSAT} observation. The 0.6--10 keV continuum is consistent with a powerlaw with $\Gamma \sim 1.6$, flatter than that typically observed…

Astrophysics · Physics 2016-08-30 I. M. George , R. F. Mushotzky , T. J. Turner , T. Yaqoob , A. Ptak , K. Nandra , H. Netzer

The Seyfert Galaxy Mrk 335 is known for its frequent changes of flux and spectral shape in the X-ray band occurred during recent years. These variations may be explained by the onset of a wind that previous, non-contemporaneous…

We report on X-ray emission from the Seyfert 2 galaxy NGC4388 observed with the Chandra X-ray Observatory. A hard X-ray peak is found at the position of the active nucleus suggested by optical and radio observations. Extended soft X-ray…

Astrophysics · Physics 2009-09-17 K. Iwasawa , A. S. Wilson , A. C. Fabian , A. J. Young

The lack of variability of the broad iron line seen in the Seyfert 1 galaxy MCG-6-30-15 is studied using the EPIC pn data obtained from a 2001 observation of 325 ks, during which the count rate from the source varied by a factor of 5. The…

Astrophysics · Physics 2009-11-07 A. C. Fabian , S. Vaughan

The X-ray source AXJ0341.4-4453 was described by Boyle et al. as a Type 2 AGN at z = 0.672 based on the absence of broad emission lines in the observed wavelength range 4000-7000 Angstroms. We obtained a new spectrum of AXJ0341.4-4453…

Astrophysics · Physics 2009-10-31 J. P. Halpern , T. J. Turner , I. M. George

Narrow Line Seyfert 1 galaxies represent a distinct category in the larger family of Type 1 Active Galactic Nuclei. The occurrence of emission line profiles not broader than 2000 km/s, combined with luminosity estimates comparable to those…

High Energy Astrophysical Phenomena · Physics 2011-06-14 G. La Mura , S. Ciroi , V. Cracco , D. Ilić , L. Č. Popović , P. Rafanelli

We have examined simultaneous X-ray and optical light curves of a sample of eight nearby Seyfert 1 galaxies observed using the EPIC X-ray cameras and Optical Monitor on board XMM. The observations span ~1 day and revealed optical…

Astrophysics · Physics 2008-11-26 R. Smith , S. Vaughan

We explore the origin of the strong soft X-ray excess in Narrow Line Seyfert 1 galaxies using spectral-timing information from a 120ks {\it XMM-Newton} observation of PG 1244+026. Spectral fitting alone cannot distinguish between a true…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Chichuan Jin , Chris Done , Matthew Middleton , Martin Ward

Results from BeppoSAX observations of Compton--thick Seyfert 2 galaxies are summarized and reviewed, and their general properties derived and discussed. In five out of the seven observed sources, the nucleus is directly visible at high…

Astrophysics · Physics 2016-08-30 G. Matt , A. C. Fabian , M. Guainazzi , K. Iwasawa , L. Bassani , G. Malaguti

We have extensively studied the broadband X-ray spectra of the source ESO~141--G055 using all available \xmm{} and \nustar{} observations. We detect a prominent soft excess below 2 keV, a narrow Fe line and a Compton hump (>10 keV). The…

High Energy Astrophysical Phenomena · Physics 2020-07-30 Ritesh Ghosh , Sibasish Laha

We search for a direct signature of discrete ''clouds'' in the broad line region (BLR) of the Seyfert galaxy NGC 4151. For this purpose we apply cross correlation (CC) analysis to a high resolution KECK spectrum of the galaxy. No such…

Astrophysics · Physics 2009-10-30 Nahum Arav , Thomas A. Barlow , Ari Laor , Wallace L. W. Sargent , Roger D. Blandford

XMM-Newton spectra of five red, 2MASS AGN, selected from a sample observed by Chandra to be relatively X-ray bright and to cover a range of hardness ratios, confirm the presence of substantial absorbing material in three sources with…

Astrophysics · Physics 2016-08-30 B. J. Wilkes , K. A. Pounds , G. D. Schmidt , P. S. Smith , R. M. Cutri , H. Ghosh , B. Nelson , D. C. Hines

New spectra of NGC 2992 from the Cerro Tololo Inter-American Observatory show that this nearby AGN has changed its type classification to a Seyfert 2 in 2006. It was originally classified as a Seyfert 1.9, and has been previously seen as a…

Astrophysics · Physics 2014-10-01 M. L. Trippe , D. M. Crenshaw , R. Deo , M. Dietrich

NGC 4151 is the brightest Seyfert 1 nucleus in X-rays. It was the first object to show short time delays in the Fe K band, which were attributed to relativistic reverberation, providing a new tool for probing regions at the black hole…

High Energy Astrophysical Phenomena · Physics 2019-10-16 Abderahmen Zoghbi , Jon Miller , Ed Cackett

We present results of a 100 ks XMM observation of the Seyfert 1.5 NGC 3227. Our best-fit broadband model to the pn spectrum consists of a moderately flat (photon index 1.57) hard X-ray power-law absorbed by cold gas with N_H = 3 * 10^21…

Astrophysics · Physics 2011-02-11 A. Markowitz , J. N. Reeves , I. M. George , V. Braito , R. Smith , S. Vaughan , P. Arévalo , F. Tombesi