English
Related papers

Related papers: Extreme Relativistic Reflection in the Active Gala…

200 papers

We perform X-ray/ultraviolet (UV) spectral and X-ray variability studies of the radio-loud narrow-line Seyfert 1 (NLS1) galaxy RX J1633.3+4719 using XMM-Newton and Suzaku observations from 2011 and 2012. The 0.3-10 keV spectra consist of an…

High Energy Astrophysical Phenomena · Physics 2016-06-14 Labani Mallick , G. C. Dewangan , P. Gandhi , R. Misra , A. K. Kembhavi

The spectrum of the bright Seyfert I galaxy MCG-6-30-15 shows a broad Fe K-alpha emission line, generally interpreted to originate very close to the central black hole which must then have a high spin. The observed X-ray variability is…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Chia-Ying Chiang , A. C. Fabian

1RXS J180408.9-342058 is a transient neutron star low-mass X-ray binary that exhibited a bright accretion outburst in 2015. We present Nustar, Swift, and Chandra observations obtained around the peak of this outburst. The source was in a…

We present an {\it XMM-Newton} EPIC observation of HE0450-2958 which may be a ``naked''quasar as suggested by Magain et al. The \xmm EPIC spectra show a substantial soft X-ray excess, a steep photon index, as well as marginal evidence for a…

Astrophysics · Physics 2008-11-26 Xin-Lin Zhou , Fang Yang , Xiao-Rong Lv , Jian-Min Wang

We analyze {\it simultaneously} six composite {\it RXTE} spectra of GX 339--4 in the hard state comprising 77 million counts collected over 196 ks. The source spectra are ordered by luminosity and spanthe range 1.6\% to 17\% of the…

High Energy Astrophysical Phenomena · Physics 2015-11-04 Javier A. Garcia , James F. Steiner , Jeffrey E. McClintock , Ronald A. Remillard , Victoria Grinberg , Thomas Dauser

We present a long (100 ks) Suzaku observation of one of the X-ray brightest AGN, MCG+8-11-11. These data were complemented with the 54-month Swift BAT spectrum, allowing us to perform a broad-band fit in the 0.6-150 keV range. The fits…

We present first INTEGRAL and XMM-Newton observations of a Seyfert galaxy, the type 2 AGN NGC 4388. Several INTEGRAL observations performed in 2003 allow us to study the spectrum in the 20 - 300 keV range. In addition two XMM-Newton…

During the disk-mediated accretion phase, the high-resolution X-ray spectrum of the low-mass X-ray binary system EXO 0748-676 reveals a photoionized plasma which is orbiting the neutron star. Our observations with the Chandra High Energy…

Astrophysics · Physics 2008-11-26 M. A. Jimenez-Garate , N. S. Schulz , H. L. Marshall

Suzaku observed a nearby Seyfert 2 galaxy NGC4945, which hosts one of the brightest active galactic nuclei above 20 keV. Combining data from the X-ray CCD camera (XIS) and the Hard X-ray Detector (HXD), the AGN intrinsic nuclear emission…

We report results from multi-epoch X-ray observations of the polar-scattered Seyfert 1 galaxy ESO 323-G77. The source exhibits remarkable spectral variability from months to years timescales. The observed spectral variability is entirely…

(abridged) The soft excess seen in the X-ray spectra of many high mass accretion rate AGN can be well modelled by reflection from a partially ionised accretion disc. However, the derived parameters are often extreme, both in terms of the…

Astrophysics · Physics 2009-11-13 M. J. Middleton , C. Done , M. Gierlinski

Approximately 10-20% of Active Galactic Nuclei are known to eject powerful jets from the innermost regions. There is very little observational evidence if the jets are powered by spinning black holes and if the accretion disks extend to the…

Astrophysics of Galaxies · Physics 2015-11-18 R. Ghosh , G. C. Dewangan , B. Raychaudhuri

We present a Suzaku observation of the dwarf Seyfert galaxy NGC4395 with an estimated black hole mass of ~10^5 Msun. Rapid and strong X-ray variability with an rms amplitude of ~60 per cent is observed in the 0.4-10 keV band with the XIS…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 K. Iwasawa , Y. Tanaka , L. C. Gallo

(Abridged) We present here a long (100ks) XMM-Newton follow-up of the Seyfert 1.8 galaxy ESO113-G010 performed in November 2005, in order to study over a longer time-scale its main X-ray properties. The source was found in a higher/softer…

We analyze an X-ray flux-limited, complete sample of 93 AGN at z< 0.1, selected from the ROSAT Bright Survey. Two thirds of the sample are Seyfert 1 galaxies (Sy1) and one third are Narrow-Line Seyfert 1 galaxies (NLSy1). We have obtained…

Astrophysics · Physics 2009-11-10 M. Salvato , J. Greiner , B. Kuhlbrodt

We present a multi-epoch X-ray spectroscopy analysis of the nearby narrow-line Seyfert I galaxy NGC 5506. For the first time, spectra taken by Chandra, XMM-Newton, Suzaku, and NuSTAR - covering the 2000-2014 time span - are analyzed…

High Energy Astrophysical Phenomena · Physics 2018-06-14 Shangyu Sun , Matteo Guainazzi , Qingling Ni , Jingchun Wang , Chenyang Qian , Fangzheng Shi , Yu Wang , Cosimo Bambi

We report the results of a 30 ks Chandra ACIS-S observation of the isolated compact object 1RXS J141256.0+792204 (Calvera). The X-ray spectrum is adequately described by an absorbed neutron star hydrogen atmosphere model with an effective…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Andrew S. H. Shevchuk , Derek B. Fox , Robert E. Rutledge

We present a systematic X-ray and multiwavelength study of a sample of 47 active galactic nuclei (AGNs) with reverberation-mapping measurements. This sample includes 21 super-Eddington accreting AGNs and 26 sub-Eddington accreting AGNs.…

Astrophysics of Galaxies · Physics 2021-04-07 Hezhen Liu , B. Luo , W. N. Brandt , Michael S. Brotherton , S. C. Gallagher , Q. Ni , Ohad Shemmer , J. D. Timlin

We present the first systematic broad-band X-ray study of super-Eddington accretion onto SMBHs with simultaneous {\it NuSTAR} and {\it XMM-Newton} or {\it Swift}/XRT observations of a sample of 8 super-Eddington accreting AGN with Eddington…

High Energy Astrophysical Phenomena · Physics 2022-12-14 Alessia Tortosa , Claudio Ricci , Luis C. Ho , Francesco Tombesi , Pu Du , Kohei Inayoshi , Jian-Min Wang , Jinyi Shangguan , Ruancun Li

Deep observations with the Very Large Array of A0620-00, performed in 2005 August, resulted in the first detection of radio emission from a black hole binary at X-ray luminosities as low as 10^{-8.5} times the Eddington limit. The measured…

Astrophysics · Physics 2009-11-11 E. Gallo , R. Fender , J. Miller-Jones , A. Merloni , P. Jonker , S. Heinz , T. Maccarone , M. van der Klis