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arXiv · astro-ph/9712285

BeppoSAX observations of PKS 0528+134

G. Ghisellini·G. Tagliaferri·L. Costamante·L. Maraschi·A. Celotti·G. Fossati·L. Bassani·M. Cappi·F. Frontera·E. Pian·A. Comastri·M. Cavallone·G. De Francesco·L. Lanteri·C. M. Raiteri·G. Sobrito·M. Villata·S. Giarrusso·B. Sacco·I. S. Glass·P. Grandi·E. Massaro·S. Molendi·P. Padovani·G. G. C. Palumbo·C. Perola·M. Salvati·A. Treves
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Abstract

We report on the BeppoSAX observations of the gamma-ray blazar PKS 0528+134 performed in Feb and Mar 1997, during a multiwavelength campaign involving EGRET and ground based telescopes. The source was in a faint and hard state, with energy spectral index alpha=0.48+-0.04 between 0.1 and 10 keV, and [2-10] keV flux of 2.7E-12 erg/cm2/s. No significant variability was observed. The source was detected in the 20-120 keV band by the PDS, with a flux lying slightly above the extrapolation from lower X-ray energies. Comparing this low state with previous higher states of the source, there is an indication that the X-ray spectrum hardens and the gamma-ray spectrum steepens when the source is fainter.

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G. Ghisellini, G. Tagliaferri, L. Costamante, L. Maraschi, A. Celotti, G. Fossati, L. Bassani, M. Cappi, F. Frontera, E. Pian, A. Comastri, M. Cavallone, G. De Francesco, L. Lanteri, C. M. Raiteri, G. Sobrito, M. Villata, S. Giarrusso, B. Sacco, I. S. Glass, P. Grandi, E. Massaro, S. Molendi, P. Padovani, G. G. C. Palumbo, C. Perola, M. Salvati, A. Treves. 1997-12-21. BeppoSAX observations of PKS 0528+134. https://doi.org/10.1016/s0920-5632(98)00255-2

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