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The HELLAS2XMM 1dF survey: on the nature of high X-ray to optical flux ratio sources
F. Fiore, M. Brusa, F. Cocchia +12
We present results from the photometric and spectroscopic identification of 122 X-ray sources discovered by XMM-Newton in the 2-10 keV band (the HELLAS2XMM 1dF sample). One of the…
Arakelian 564: An XMM-Newton view
C. Vignali, W. N. Brandt, Th. Boller +2
We report on two XMM-Newton observations of the bright narrow-line Seyfert 1 galaxy Ark 564 taken one year apart (2000 June and 2001 June). The 0.6-10 keV continuum is well describ…
Restless Quasar Activity: From BeppoSAX to Chandra and XMM-Newton
C. Vignali, A. Comastri, W. N. Brandt
We briefly review some of the progress made in the last decade in the study of the X-ray properties of the quasar population from the luminous, local objects observed by BeppoSAX t…
Probing the Complex and Variable X-ray Absorption of Markarian 6 with XMM-Newton
S. Immler, W. N. Brandt, C. Vignali +4
We report on an X-ray observation of the Seyfert 1.5 galaxy Mrk 6 obtained with the EPIC instruments onboard XMM-Newton. Archival BeppoSAX PDS data from 18-120 keV were also used t…
Chandra and XMM-Newton observations of the first quasars: X-rays from the age of cosmic enlightenment
C. Vignali, W. N. Brandt, D. P. Schneider +6
We report on Chandra and XMM-Newton observations of a sample of 13 quasars at z~4.7-5.4 mostly taken from the Sloan Digital Sky Survey (SDSS). The present sample complements previo…
The BeppoSAX High Energy Large Area Survey (HELLAS) - VI. The radio properties
P. Ciliegi, C. Vignali, A. Comastri +3
We present results of a complete radio follow-up obtained with the VLA and ATCA radio telescopes down to a 6 cm flux limit of about 0.3 mJy of all the 147 X-ray sources detected in…