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BL Lacertae: the multiwavelength campaign of 2000

M. Ravasio·G. Tagliaferri·G. Ghisellini·M. Boettcher·H. D. Aller·M. F. Aller·O. Mang·L. Maraschi·E. Massaro·C. M. Raiteri·M. Villata·H. Teraesranta
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Abstract

We present two BeppoSAX observations of BL Lacertae as part of a multiwavelength radio-to-TeV campaign. During the first observation we observe a faint Compton spectrum, while during the second, we detect a synchrotron spectrum with the highest [2-10] keV flux ever measured; above 10 keV an inverse Compton component begin to dominate. The synchrotron flux is very variable with time scales of 1 hr. We describe four different SED shifting the synchrotron peak both in frequency and flux intensity and we sketch a scenario in which a blob moves along a jet and can be located in or outside the BLR. This implies different radiative mechanism at work, SSC or external Compton, producing different high energy spectra.

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M. Ravasio, G. Tagliaferri, G. Ghisellini, M. Boettcher, H. D. Aller, M. F. Aller, O. Mang, L. Maraschi, E. Massaro, C. M. Raiteri, M. Villata, H. Teraesranta. 2002-10-18. BL Lacertae: the multiwavelength campaign of 2000. https://arxiv.org/abs/astro-ph/0210415

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