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ABSTRACT We preset first results of the long term monitoring of Seyfert Galaxies with BeppoSAX Wide Field Cameras (WFCs). We have firstly examined the data of the Seyfert 1.5 NGC 4151, This object is known to be one of the brightest Seyferts ranging from few to about 15 mCrab in the 2 - 10 keV energy range. As of September 13, 1998, the sky region containing NGC 4151 has been observed by WFCs in secondary mode (i.e., when the narrow field instruments are performing prime observations) about 80 times. We report here the results of the analysis of 21 observations. The minimum flux at which the source was detected is ∼ 4 mCrab, In June of this year we found the source at ∼ 20 mCrab, the highest state ever recorded. The study of the light curve of the very faint and stable source Cas A gives a preliminary assessment of systematic errors of ∼20%. The preliminary results obtained, confirm that the WFCs are powerful tools for the study of bright AGN. [ABSTRACT FROM AUTHOR]

ABSTRACT We present selected results of the GRB detection and positioning at the BeppoSAX SOC, highlighting the improvement of procedures and Quick Look Analysis effectiveness from early detections to up to date observations. We describe the physical and technical features of fast and reliable GRB detections and we show how the switch from the 3-gyro mode to the Extended Science Mode (ESM), occurred in Aug. 1997, has not reduce the SAX capability of detecting GRBs with the Wide Field Cameras (WFCs), the distribution of coordinates and the rapid repointing of the Narrow Field Instruments (NFI) to the X-Ray afterglow. [ABSTRACT FROM AUTHOR]

ABSTRACT GRB980519 represents the 13th gamma-ray burst (GRB) detected by the BeppoSAX Wide Field Cameras (WFCs) (to date a total of 20 GRBs have been localized with arcmin accuracies). Afterglow emission was observed from the X-ray to the radio wavelengths. The GRB980519 decay is particularly fast compared to other GRBs. A candidate host galaxy with magnitude R[sub c] = 26 has been reported. [ABSTRACT FROM AUTHOR]

ABSTRACT Preliminary results from a BeppoSAX NFI observation of Mkn421 in a very bright state are reported together with monitoring data collected with the BeppoSAX-WFC and the RXTE-ASM. The BeppoSAX observation was carried out as part of a Target Of Opportunity program aimed at the study of AGN near record level intensity states. The comparison of our results with those of previous observations of Mkn421 shows clear evidence for strong spectral evolution. [ABSTRACT FROM AUTHOR]

ABSTRACT We present BeppoSAX broad band (0.1-200 keV) spectral results on a sample of bright Seyfert 1 galaxies, chosen to be representative of the class as a whole. The objects discussed ill this paper are: Fairall 9, NGC 5506, NGC 4593 and IC 4329A. In all of them a (broad) iron line and the Compton reflection continuum are clearly detected. In one of them (IC 4329A) a high energy cut-off with e-folding energy of 350 keV is also present. [ABSTRACT FROM AUTHOR]