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arXiv · astro-ph/9906165

The blazar PKS 0528+134: new results from BeppoSAX observations

G. Ghisellini·L. Costamante·G. Tagliaferri·L. Maraschi·A. Celotti·G. Fossati·E. Pian·A. Comastri·G. De Francesco·L. Lanteri·C. M. Raiteri·G. Sobrito M. Villata·I. S. Glass·P. Grandi·P. Padovani·C. Perola·A. Treves
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Abstract

BeppoSAX observed 8 times the gamma-ray bright blazar PKS 0528+134 in Feb. and Mar. 1997, during a multiwavelength campaign involving EGRET, onboard CGRO, and ground based telescopes. The source was in its faintest X-ray state observed so far, with an unabsorbed [2-10] keV flux of 2.5E-12 erg/cm2/s. The spectrum can be fitted with a power law, with energy index alpha_X=0.49+-0.07 between 0.1 and 10 keV. The high energy instrument PDS detected a flux in the 15-100 keV band which appears disconnected from the lower X-ray energies, most likely due to a contaminating source. We consider our findings in the context of the overall spectral energy distribution and discuss their implications for synchrotron and inverse Compton models.

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G. Ghisellini, L. Costamante, G. Tagliaferri, L. Maraschi, A. Celotti, G. Fossati, E. Pian, A. Comastri, G. De Francesco, L. Lanteri, C. M. Raiteri, G. Sobrito M. Villata, I. S. Glass, P. Grandi, P. Padovani, C. Perola, A. Treves. 1999-06-09. The blazar PKS 0528+134: new results from BeppoSAX observations. https://arxiv.org/abs/astro-ph/9906165

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