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 2.5 x 10(-12) erg cm(-2) s(-1). 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.
The blazar PKS 0528+134: new results from BeppoSAX observations / Ghisellini, G.; Tagliaferri, G.; Costamante, L.; Maraschi, L.; Celotti, Anna Lisa; 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.; Molendi, S.; Padovani, P.; Palumbo, G. G. C.; Perola, C.; Salvati, M.; Treves, A.. - In: ASTRONOMY & ASTROPHYSICS. - ISSN 0004-6361. - 348:1(1999), pp. 63-70.
The blazar PKS 0528+134: new results from BeppoSAX observations
Celotti, Anna Lisa;
1999-01-01
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 2.5 x 10(-12) erg cm(-2) s(-1). 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
