BeppoSAX observations of PKS 0528+134

• Published in: Nuclear physics. Section B, Proceedings supplement Proceedings supplement, 1999-01, Vol.69 (1), p.427-430
• Main Authors: Ghisellini, G., Tagliaferri, G., Costamante, L., Maraschi, L., Celotti, A., Fossati, G., Bassani, L., Cappi, M., Frontera, F., Pian, E., Comastri, A., Cavallone, M., De Francesco, G., Lanteri, L., Raiteri, C.M., Sobrito, G., Villata, M., Giarrusso, S., Sacco, B., Glass, I.S., Grandi, P., Massaro, E., Molendi, S., Padovani, P., Palumbo, G.G.C., Perola, C., Salvati, M., Treves, A.
• Format: Article
• Language: English
• ISSN: 0920-5632; 1873-3832
• DOI: 10.1016/S0920-5632(98)00255-2

We report on the BeppoSAX observations of the γ-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 α = 0.48 ± 0.04 between 0.1 and 10 keV, and [2–10] keV flux of 2.7 × 10 −12 erg cm −2 s −1. 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 γ-ray spectrum steepens when the source is fainter.