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Related papers: An X-ray view of the INTEGRAL/IBIS blazars

200 papers

We use Swift blazar spectra to estimate the key intergalactic medium (IGM) properties of hydrogen column density(Nhxigm), metallicity and temperature over a redshift range of 0.03 leq z leq 4.7, using a collisional ionisation…

High Energy Astrophysical Phenomena · Physics 2021-09-22 Tony Dalton , Simon L. Morris , Michele Fumagalli , Efrain Gatuzz

We report on two XMM-Newton observations of the low-mass X-ray binary X 1254-690. During an XMM-Newton observation of the low-mass X-ray binary in 2001 January a deep X-ray dip was seen while in a second observation one year later no dips…

Astrophysics · Physics 2009-11-10 L. Boirin , A. N. Parmar

PKS 0537-441, a bright gamma-ray emitting blazar, was observed at radio, optical, UV and X-ray frequencies during various EGRET pointings, often quasi-simultaneously. In 1995 the object was found in an intense emission state at all…

We report on a simultaneous observational campaign with both Swift/XRT and NuSTAR targeting the symbiotic X-ray binary IGR J16194-2810. The main goal of the campaign was to investigate the possible presence of cyclotron scattering…

High Energy Astrophysical Phenomena · Physics 2023-11-14 E. Bozzo , P. Romano , C. Ferrigno , L. Ducci

During hard X-ray observations of the Norma spiral arm region by the Nuclear Spectroscopic Telescope Array (NuSTAR) in 2013 February, a new transient source, NuSTAR J163433-4738.7, was detected at a significance level of 8-sigma in the 3-10…

We present a spectroscopic study of 41 hard X-ray sources detected serendipitously with high significance (> 5 sigma in the 2-10 keV band) in seven EPIC performance/verification phase observations. The large collecting area of EPIC allows…

Astrophysics · Physics 2009-11-07 E. Piconcelli , M. Cappi , L. Bassani , F. Fiore , G. DiCocco , J. B. Stephen

We report on the X-ray monitoring programme (covering slightly more than 11 days) carried out jointly by XMM-Newton and NuSTAR on the intermediate Seyfert galaxy Mrk 915. The light curves extracted in different energy ranges show a…

High Energy Astrophysical Phenomena · Physics 2017-07-26 L. Ballo , P. Severgnini , R. Della Ceca , V. Braito , S. Campana , A. Moretti , C. Vignali , A. Zaino

Using the latest 70 month Swift-BAT catalog we examined hard X-ray selected Seyfert I galaxies which are relatively little known and little studied, and yet potentially promising to test the ionized relativistic reflection model. From this…

Astrophysics of Galaxies · Physics 2014-12-03 Andrew C. Liebmann , Andrew C. Fabian , Sachiko Tsuruta

We report on the extreme behaviour of the high redshift blazar GB B1428+4217 at z=4.72. A continued programme of radio measurements has revealed an exceptional flare in the lightcurve, with the 15.2 GHz flux density rising by a factor ~3…

Astrophysics · Physics 2009-09-17 M. A. Worsley , A. C. Fabian , G. G. Pooley , C. J. Chandler

A new sample of hard X-ray sources in the Galactic Plane is being revealed by the regular observations performed by the INTEGRAL satellite. The full characterization of these sources is mandatory to understand the hard X-ray sky. Here we…

Astrophysics · Physics 2007-05-23 J. A. Combi , M. Ribo , J. Marti , S. Chaty

This paper presents the analysis of a statistically complete sample of 28 serendipitous X-ray sources selected in 82 pointed XMM-Newton fields down to a count-rate of 0.002 counts s^-1(4.5-7.5 keV energy band). This is the first sample…

We present X-ray spectral analyses for three Seyfert 2 active galactic nuclei, NGC 424, NGC 1320, and IC 2560, observed by NuSTAR in the 3-79 keV band. The high quality hard X-ray spectra allow detailed modeling of the Compton reflection…

The two-component broad-band spectral energy distributions of blazars were suggested to form a sequence in which (1) the peak frequency of the low-energy (synchrotron) component nu_syn is anticorrelated with the synchrotron luminosity…

High Energy Astrophysical Phenomena · Physics 2017-10-11 Krzysztof Nalewajko , Maitrayee Gupta

We report on the \nustar{} observation of the newly discovered neutron star X-ray binary Swift~J1858.6-0814 taken on 23rd March 2019. The light curve of the source exhibits several large flares during some time intervals of this…

High Energy Astrophysical Phenomena · Physics 2023-08-02 Aditya S. Mondal , B. Raychaudhuri , Gulab C Dewangan

We observed with Suzaku the symbiotic star SS73 17, motivated by the discovery by the INTEGRAL satellite and the Swift BAT survey that it emits hard X-rays. Our observations showed a highly-absorbed X-ray spectrum with NH > 10^23 cm-2,…

We investigate the relationship between the long term X-ray spectral variability in the Seyfert 1.5 galaxy NGC 4151 and its intrinsic absorption, by comparing the 2014 simultaneous ultraviolet/X-Ray observations taken with Hubble STIS…

Astrophysics of Galaxies · Physics 2016-12-21 J. D. Couto , S. B. Kraemer , T. J. Turner , D. M. Crenshaw

We present an analysis of hard X-ray features in the spectrum of the bright Sy 1 galaxy Mrk 335 observed by the XMM-Newton satellite. Our analysis confi rms the presence of a broad, ionised iron Kalpha emission line in the spectrum, first…

Astrophysics · Physics 2008-11-26 Anna Lia Longinotti , Stuart Sim , Kirpal Nandra , Massimo Cappi

Early results from the INTEGRAL Core Program, for a sample of eight persistently bright neutron star low mass X-ray binaries in the energy range from 5 keV to 200 keV are presented. It is shown that INTEGRAL efficiently detects sources and…

The pair-production absorption of high-energy gamma-rays by intergalactic low-energy photons is expected to produce a high-energy cutoff in the spectra of extragalactic sources which is a sensitive function of redshift. We first discuss the…

Astrophysics · Physics 2007-05-23 F. W. Stecker

We present results from an analysis of the broad-band, 0.3-195 keV, X-ray spectra of 48 Seyfert 1-1.5 sources detected in the very hard X-rays with the Swift Burst Alert Telescope (BAT). This sample is selected in an all-sky survey…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Lisa M. Winter , Sylvain Veilleux , Barry McKernan , Tim Kallman
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