We present the results of the BeppoSAX observations of two BL Lacs, OQ530 and S5 0716+714, as part of a ToO program for the simultaneous observation at radio, optical, X-ray and TeV energies. Both sources are detected in the LECS and MECS, with S5 0716+714 visible also in the PDS band, up to about similar to60 keV. The X-ray spectra of both sources are better fitted by a double power-law model, with a steep soft X-ray component flattening at harder energies, with breaks at 0.3 and 1.5 keV, respectively. The concave shape of the spectra in both objects is consistent with soft X-rays being produced by the synchrotron and harder X-rays by the inverse Compton processes. Also the X-ray variability properties confirm this scenario; in particular, for S5 0716+714 our observation shows variations by about a factor of 3 over one hour below similar to3 keV and no variability above. Their simultaneous broad-band energy spectral distributions can be successfully interpreted within the frame of a homogeneous synchrotron and inverse Compton model, including a possible contribution from an external source of seed photons with the different spectral states of S5 0716+714 being reproduced by changing the injected power. The resulting parameters are fully consistent with the two sources being intermediate objects within the "sequence" scenario proposed for blazars.
|Titolo:||The BL lacertae objects OQ 530 and S5 0716+714 - Simultaneous observations in the X-rays, radio, optical and TeV bands|
|Autori:||Tagliaferri, G.; Ravasio, M.; Ghisellini, G.; Giommi, P.; Massaro, E.; Nesci, R.; Tosti, G.; Aller, M. F.; Aller, H. D.; Celotti, A.; Maraschi, L.; Tavecchio, F.; Wolter, A.|
|Data di pubblicazione:||2003|
|Digital Object Identifier (DOI):||10.1051/0004-6361:20021916|
|Fulltext via DOI:||10.1051/0004-6361:20021916|
|Appare nelle tipologie:||1.1 Journal article|