7 papers · 1 filter
The concave X-ray spectrum of the blazar ON 231: the signature of intermediate BL Lac objects
G. Tagliaferri, G. Ghisellini, P. Giommi +17
ON 231 was observed with BeppoSAX in May and June 1998, following an exceptional optical outburst which occured in April--May. We measured the X-ray spectrum from 0.1 up to 100 keV…
Synchrotron and Inverse Compton Variability in the BL Lacertae object S5 0716+714
P. Giommi, E. Massaro, L. Chiappetti +14
We report intensity variations of different spectral components in the BL Lac object S5 0716+714 detected during coordinated BeppoSAX and optical observations in 1996 and 1998. The…
ISO observations of the BL Lac object PKS 2155-304
E. Bertone, G. Tagliaferri, G. Ghisellini +3
The Infrared Space Observatory (ISO) observed the BL Lac object PKS 2155-304 16 times from 1996, May 7 to June 8, with both the ISOCAM camera and the ISOPHOT photometer, as part of…
X-ray Rapid Variability of MKN 421
A. Treves, Y. H. Zhang, F. Tavecchio +7
We present a detailed Cross Correlation analysis of the light curves of the X-ray bright BL Lac object Mkn 421 observed with SAX period 1997-1998. Monte Carlo simulations ar…
The VIRMOS mask manufacturing tools: (b) Mask manufacturing and handling
G. Conti, L. Chiappetti, E. Mattaini +4
We describe the VIRMOS Mask Manufacturing Unit (MMU) configuration, composed of two units:the Mask Manufacturing Machine (with its Control Unit) and the Mask Handling Unit (inclusi…
Hour-Scale Multiwavelength Variability in Markarian 421
M. Catanese, I. H. Bond, S. M. Bradbury +36
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 variab…