English
Related papers

Related papers: Correlations between X-ray spectral parameters of …

200 papers

We present a model of the spectra of gamma-ray emitting blazars in which a single homogeneous emission region both emits synchrotron photons directly and scatters them to high (gamma-ray) energy before emission (a ``synchrotron…

Astrophysics · Physics 2016-08-30 A. Mastichiadis , J. G. Kirk

Markarian 421 was observed for about four days with BeppoSAX and the Whipple Observatory gamma-ray telescope in April 1998. A pronounced, well-defined, flare with hour-scale variability was observed simultaneously in X-rays and very high…

This work is a summary of the X-ray spectral studies of 29 TeV $\gamma$-ray emitting blazars observed with Swift/XRT, especially focusing on sources for which X-ray regime allows to study the low and the high energy ends of the particle…

High Energy Astrophysical Phenomena · Physics 2016-01-28 Alicja Wierzcholska , Stefan Wagner

One of the most important predictions of any gap model for pulsar magnetospheres is the predicted $\gamma$-ray spectra. In the outer gap model, the properties of the synchro-curvature radiation are sensitive to many parameters, whose…

High Energy Astrophysical Phenomena · Physics 2015-04-02 Daniele Viganò , Diego F. Torres , Kouichi Hirotani , Martín E. Pessah

We characterized the broad-band X-ray spectra of Swift J1745-26 during the decay of the 2013 outburst using INTEGRAL ISGRI, JEM-X and Swift XRT. The X-ray evolution is compared to the evolution in optical and radio. We fit the X- ray…

We analyzed changes in the height of the coronal hard X-ray (HXR) source for flares SOL2013-05-13T01:50 and SOL2013-05-13T15:51. Analysis of the Reuven Ramaty High Energy Solar Spectroscopic Imager data revealed the downward motion of the…

Solar and Stellar Astrophysics · Physics 2023-09-13 Alexander N. Shabalin , Evgeniia P. Ovchinnikova , Yuri E. Charikov

The blazar Mrk 421 is one of the closest, brightest and fastest varying source in the extragalactic X-ray/TeV sky. In the last years, many multi-wavelength campaigns have been carried out to study the correlation between the very high…

High Energy Astrophysical Phenomena · Physics 2015-08-27 Barbara Patricelli , Magdalena González , Nissim Fraija

We present a comprehensive, two-decade, multiwavelength variability study of the blazar PKS 1510-089, one of the most prominent and extensively monitored flat-spectrum radio quasars. Using Fermi-LAT $\gamma$-ray data together with Swift-XRT…

High Energy Astrophysical Phenomena · Physics 2026-04-02 M. Zacharias , A. Wierzcholska

We present the results from the spectral analysis of more than 7,500 RXTE spectra of 10 AGN, which have been observed by RXTE regularly over a long period of time ~ 7-11 years. These observations most probably sample most of the flux and…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 M. A. Sobolewska , I. E. Papadakis

We study the spectral and energetics properties of 47 long-duration gamma-ray bursts (GRBs) with known redshift, all of them detected by the Swift satellite. Due to the narrow energy range (15-150 keV) of the Swift-BAT detector, the…

Astrophysics · Physics 2009-11-13 J. I. Cabrera , C. Firmani , V. Avila-Reese , G. Ghirlanda , G. Ghisellini , L. Nava

Aims: We used data from the 58 month long, continuous Swift/Burst Alert Telescope (BAT) observations of the five brightest Seyfert galaxies at hard X-rays, to study their flux and spectral variability in the 20-100 keV energy band. The…

High Energy Astrophysical Phenomena · Physics 2015-05-30 M. D. Caballero-Garcia , I. E. Papadakis , F. Nicastro , M. Ajello

Context: We present the results of a set of observations of nine TeV detected BL Lac objects performed by the XRT and UVOT detectors on board the Swift satellite between March and December 2005. Aims: We are mainly interested in measuring…

We present an ordinary case in the momentum diffusion equation for the electron spectrum evolution and investigate the energy spectra and time dependent properties of flare in Mrk 421 in the frame of a time-dependent one-zone synchrotron…

High Energy Astrophysical Phenomena · Physics 2016-08-02 Y. G. Zheng , S. J. Kang , J. Li

The long gamma-ray burst GRB 060714 was observed to exhibit a series of five X-ray flares beginning ~70 s after the burst trigger T0 and continuing until T0 + ~200 s. The first two flares were detected by the Burst Alert Telescope (BAT) on…

Using Gaussian process methods, we analyzed the light curves of three extreme solar X-ray flares observed by the RHESSI satellite. Their variability characteristics were then compared with those of HXMT-HE X-ray burst (XRB; in SGR…

High Energy Astrophysical Phenomena · Physics 2025-12-15 Haiyun Zhang , Dahai Yan , Lijuan Dong , Ping Zhang , Ruijing Tang , Jianeng Zhou , Lian Tao , Li Zhang , Niansheng Tang

Split-pulse x-ray photon correlation spectroscopy has been proposed as one of the unique capabilities made possible with the x-ray free electron lasers. It enables characterization of atomic scale structural dynamics that dictates the…

Instrumentation and Detectors · Physics 2020-05-06 Yanwen Sun , Mike Dunne , Paul Fuoss , Taito Osaka , Aymeric Robert , Mark Sutton , Makina Yabashi , Diling Zhu

The BL Lac object Mkn~421 was observed three times by the X-ray observatory BeppoSAX in consecutive days during 1997 April and May. The source was in a quiescent state, with an average 2-10 keV flux of 9.0 x 10^(-11) erg/cm/cm/s. Flux…

Astrophysics · Physics 2007-05-23 M. Guainazzi , G. Vacanti , A. Malizia , K. S. O'Flaherty , E. Palazzi , A. N. Parmar

We present X-ray flux and spectral analyses of the three pointed Suzaku observations of the TeV high synchrotron peak blazar Mrk 421 taken throughout its complete operational duration. The observation taken on 5 May 2008 is, at 364.6…

High Energy Astrophysical Phenomena · Physics 2019-11-06 Zhongli Zhang , Alok C. Gupta , Haritma Gaur , Paul J. Wiita , Tao An , Minfeng Gu , Dan Hu , Haiguang Xu

We present cross-correlation studies of gamma-ray (0.1-300 GeV), X-ray (0.2-10 keV) and optical (R-band) variability of a sample of 26 blazars during 2008-2016. The light curves are from Fermi-LAT, Swift-XRT, and the Yale-SMARTS blazar…

High Energy Astrophysical Phenomena · Physics 2020-04-08 Anwesh Majumder , Kaustav Mitra , Ritaban Chatterjee , C. M. Urry , C. D. Bailyn , Prantik Nandi

Blazars are the most extreme subclass of active galactic nuclei with relativistic jets emerging from a super-massive black hole and forming a small angle with respect to our line of sight. Blazars are also known to be related to flaring…

High Energy Astrophysical Phenomena · Physics 2021-08-02 Stamatios I. Stathopoulos , Maria Petropoulou , Paolo Giommi , Georgios Vasilopoulos , Paolo Padovani , Apostolos Mastichiadis