143 citations · 1.3k across the 30 of their papers we have counts for
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A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
C. M. Raiteri, M. Villata, V. M. Larionov +2
We present and analyse the WEBT multifrequency observations of 3C 454.3 in the 2007-2008 observing season, including XMM-Newton observations and near-IR spectroscopic monitoring, a…
A jet model for Galactic black-hole X-ray sources: Some constraining correlations
N. D. Kylafis, I. E. Papadakis, P. Reig +2
Some recent observational results impose significant constraints on all the models that have been proposed to explain the Galactic black-hole X-ray sources in the hard state. In pa…
The long-term optical spectral variability of BL Lacertae
I. E. Papadakis, M. Villata, C. M. Raiteri
We present the results from a study of the long-term optical spectral variations of BL Lacertae, using the long and well-sampled B and R-band light curves of the Whole Earth Blazar…
XMM-Newton timing mode observations of Mrk 421
W. Brinkmann, I. E. Papadakis, C. Raeth +2
We present the results of a detailed temporal analysis of the bright BL Lac object Mrk 421 using the three available long timing mode observations by the EPIC PN camera. This detec…
Multiwavelength Observations of 3C 66A during the WEBT campaign of 2003 - 2004
M. Boettcher, J. Harvey, M. Joshi
The BL Lac object 3C 66A was the target of an extensive multiwavelength monitoring campaign from July 2003 through April 2004, involving observations throughout the electromagnetic…
The WEBT campaign to observe AO 0235+16 in the 2003-2004 observing season
C. M. Raiteri, M. Villata, M. A. Ibrahimov +2
A multiwavelength campaign on the BL Lac object AO 0235+16 has been organized by the WEBT collaboration during the observing seasons 2003-2004 and 2004-2005. Here we report on the…
The WEBT BL Lacertae Campaign 2001 and its extension
M. Villata, C. M. Raiteri
BL Lacertae has been the target of four observing campaigns by the Whole Earth Blazar Telescope (WEBT) collaboration. In this paper we present light curves obtained by the…
Aperiodic variability of low-mass X-ray binaries at very low frequencies
P. Reig, I. Papadakis, N. D. Kylafis
We have obtained discrete Fourier power spectra of a sample of persistent low-mass neutron-star X-ray binaries using long-term light curves from the All Sky Monitor on board the Ro…
On the Nature of X-ray Variability in Ark 564
M. Gliozzi, W. Brinkmann, C. Raeth +3
We use data from a recent long ASCA observation of the Narrow Line Seyfert 1 Ark 564 to investigate in detail its timing properties. We show that a thorough analysis of the time se…
Detection of a high frequency break in the X-ray power spectrum of Ark 564
I. E. Papadakis, W. Brinkmann, H. Negoro +1
We present a power spectrum analysis of the long ASCA observation of Ark 564 in June/July 2001. The observed power spectrum covers a frequency range of ~ 3.5 decades. We detect a h…
Multiwavelength Monitoring of the Narrow-Line Seyfert 1 Galaxy Akn 564. III. Optical Observations and the Optical--UV--X-ray Connection
O. Shemmer, P. Romano, R. Bertram +36
We present the results of a two-year long optical monitoring program of the narrow-line Seyfert 1 galaxy Akn 564. The majority of this monitoring project was also covered by X-ray…