361 citations · 8.4k across the 127 of their papers we have counts for
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Suzaku Observations of Extreme MeV Blazar SWIFT J0746.3+2548
Shin Watanabe, Rie Sato, Tadayuki Takahashi +8
We report the Suzaku observations of the high luminosity blazar SWIFT J0746.3+2548 (J0746) conducted in November 2005. This object, with z = 2.979, is the highest redshift source o…
Testing the blazar spectral sequence: X-ray selected blazars
L. Maraschi, L. Foschini, G. Ghisellini +2
We present simultaneous optical and X-ray data from Swift for a sample of FSRQs selected from the EMSS survey. We present also a complete analysis of Swift and INTEGRAL data on 4 b…
A novel method for measuring the extragalactic background light: Fermi application to the lobes of Fornax A
Markos Georganopoulos, Rita M. Sambruna, Demosthenes Kazanas +5
We describe a new method for measuring the extragalactic background light (EBL) through the detection of -ray inverse Compton (IC) emission due to scattering of the EBL photons…
Radio spectra of intermediate-luminosity broad-line radio galaxies
E. Angelakis, M. Kadler, K. Lewis +3
Within the context of investigating possible differences between the mechanisms at play in Radio Loud AGN and those in Radio Quiet ones, we study the spectral characteristics of a…
A kpc-scale X-ray jet in the BL Lac source S5 2007+777
Rita M. Sambruna, Davide Donato, C. C. Cheung +2
X-ray jets in AGN are commonly observed in FRII and FRI radio-galaxies, but rarely in BL Lacs, most probably due to their orientation close to the line of sight and the ensuing for…
Infrared to X-ray observations of PKS 2155-304 in a low state
L. Foschini, A. Treves, F. Tavecchio +14
AIMS: Our goal is to understand the nature of blazars and the mechanisms for the generation of high-energy gamma-rays, through the investigation of the prototypical blazar PKS 2155…
The Spectral Sequence of Blazars - Status and Perspectives
L. Maraschi, G. Ghisellini, F. Tavecchio +2
The present status of the blazar spectral sequence is discussed, including new findings about blazars selected with different criteria than the original complete radio-samples. Des…
Long-Term X-Ray monitoring of NGC6251: Evidence for a jet-dominated radio galaxy
M. Gliozzi, I. E. Papadakis, R. M. Sambruna
We present the first X-ray monitoring observations of the X-ray bright FRI radio galaxy NGC6251 observed with RXTE for 1 year. The primary goal of this study is to shed light on th…
The polyhedral nature of LINERs: An XMM-Newton view of LINERs in radio galaxies
M. Gliozzi, L. Foschini, R. M. Sambruna +1
Aims: We investigate the origin of X-rays and the nature of accretion flow in 4 LINERs hosted by radio galaxies, namely NGC1692, PKS0625-35, 3C88, 3C444, recently observed with XMM…
Blazar microvariability at hard X-rays
L. Foschini, M. Gliozzi, E. Pian +10
Blazars are known to display strong and erratic variability at almost all the wavelengths of electromagnetic spectrum. Presently, variability studies at high-energies (hard X-rays,…
Deep Chandra and multicolor HST observations of the jets of 3C 371 and PKS 2201+044
R. M. Sambruna, D. Donato, F. Tavecchio +3
This paper presents multiwavelength imaging and broad-band spectroscopy of the relativistic jets in the two nearby radio galaxies 3C 371 and PKS 2201+044, acquired with Chandra, HS…
Swift observations of high-redshift radio-loud quasars
R. M. Sambruna, F. Tavecchio, G. Ghisellini +5
We report on Swift observations of four z>2 radio-loud quasars (0212+735, 0537-286, 0836+710, and 2149-307), classified as blazars. The sources, well-known emitters at soft-medium…
An X-ray jet in the BL Lac S5 2007+777
R. M. Sambruna, D. Donato, C. C. Cheung +2
The BL Lac S5 2007+777 was observed by us with Chandra, to find the X-ray counterpart to its 18" radio jet, and study its structure. Indeed, a bright X-ray jet was discovered in th…
Low energy cut-offs and hard X-ray spectra in high-z radio-loud quasars: the Suzaku view of RBS315
F. Tavecchio, L. Maraschi, G. Ghisellini +4
We present the results from the Suzaku observation of the powerful radio-loud quasar RBS315 (z=2.69), for which a previous XMM-Newton observation showed an extremely flat X-ray con…
The remarkable X-ray spectrum of the Broad-Line Radio Galaxy 3C 445
R. M. Sambruna, J. N. Reeves, V. Braito
We present the results of the analysis of an archival 15 ks XMM-Newton observation of the nearby (z=0.057) radio-loud source 3C445, optically classified as a Broad-Line Radio Galax…
The nature of a broad line radio galaxy: Simultaneous RXTE and Chandra HETG observations of 3C 382
M. Gliozzi, R. M. Sambruna, M. Eracleous +1
We present the results from simultaneous chandra and rxte observations of the X-ray bright Broad-Line Radio Galaxy (BLRG) 3C 382. The long (120 ks) exposure with chandra HETG allow…
X-Raying the MOJAVE Sample of Compact Extragalactic Radio Jets
M. Kadler, G. Sato, J. Tueller +4
The MOJAVE sample is the first large radio-selected, VLBI-monitored AGN sample for which complete X-ray spectral information is being gathered. We report on the status of Swift sur…
Can GLAST detect gamma-rays from the extended radio features of radio galaxies?
R. M. Sambruna, M. Georganopoulos, D. Davis +1
A few FRI radio galaxies were detected at GeV gamma-rays with CGRO EGRET, with peroperties suggesting that the gamma-ray flux originates from the core. Here we discuss the possibil…
Does the Blazar Gamma-Ray Spectrum Harden with Increasing Flux? Analysis of 9 Years of EGRET Data
Giridhar Nandikotkur, Keith M. Jahoda, R. C. Hartman +5
The Energetic Gamma-Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory (CGRO) discovered gamma-ray emission from more than 67 blazars during its 9 yr lifetime. W…
Swift follow-up of the gigantic TeV outburst of PKS 2155-304 in 2006
L. Foschini, G. Ghisellini, F. Tavecchio +12
At the end of July 2006, the blazar PKS 2155-304 (z=0.116) underwent a strong outburst observed at TeV energies by HESS (up to 17 Crab flux level at E > 200 GeV). The Swift satelli…
An Infrared Study of the Large-scale Jet in Quasar PKS 1136-135
Y. Uchiyama, C. M. Urry, P. Coppi +6
We present Spitzer IRAC imaging of the large-scale jet in the quasar PKS 1136-135 at wavelengths of 3.6 and 5.8 um, combined with previous VLA, HST, and Chandra observations. We cl…
Chandra and HST observations of gamma-ray blazars: comparing jet emission at small and large scales
F. Tavecchio, L. Maraschi, A. Wolter +3
We present new Chandra and HST data for four gamma-ray blazars selected on the basis of radio morphology with the aim of revealing X-ray and optical emission from their jets at lar…
A Chandra view of Naked Active Galactic Nuclei
M. Gliozzi, R. M. Sambruna, L. Foschini
We present the first X-ray observations of three sources belonging to a new AGN class: the naked AGNs. Based on optical spectroscopic studies, these sources appear as classical typ…
X-ray/UV/Optical follow-up of the blazar PKS 2155-304 after the giant TeV flares of July 2006
L. Foschini, G. Ghisellini, F. Tavecchio +12
We present all the publicly available data, from optical/UV wavelengths (UVOT) to X-rays (XRT, BAT), obtained from Swift observations of the blazar PKS 2155-304, performed in respo…