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

BeppoSAX observed 8 times the gamma-ray bright blazar PKS 0528+134 in Feb. and Mar. 1997, during a multiwavelength campaign involving EGRET, onboard C GRO, and ground based telescopes. The source was in its faintest X-ray stat e observed so far, with an unabsorbed [2-10] keV flux of 2.5 x 10(-12) erg cm(-2) s(-1). The spectrum can be fitted with a power law, with energy inde x alpha(X) = 0.49 +/- 0.07 between 0.1 and 10 keV. The high energy instrume nt PDS detected a flux in the 15-100 keV band which appears disconnected fr om the lower X-ray energies, most likely due to a contaminating source. We consider our findings in the context of the overall spectral energy distrib ution and discuss their implications for synchrotron and inverse Compton mo dels.