The 0.1-200 keV spectrum of the blazar PKS 2005-489 during an active state

G. Tagliaferri; G. Ghisellini; P. Giommi; A. Celotti; M. Chiaberge; L. Chiappetti; I. S. Glass; L. Maraschi; F. Tavecchio; A. Treves; A. Wolter

doi:10.1051/0004-6361:20010011

arXiv · astro-ph/0012503

The 0.1-200 keV spectrum of the blazar PKS 2005-489 during an active state

G. Tagliaferri·G. Ghisellini·P. Giommi·A. Celotti·M. Chiaberge·L. Chiappetti·I. S. Glass·L. Maraschi·F. Tavecchio·A. Treves·A. Wolter

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Abstract

The bright BL Lac object PKS 2005-489 was observed by BeppoSAX on November 1-2, 1998, following an active X-ray state detected by RossiXTE. The source, detected between 0.1 and 200 keV, was in a very high state with a continuum well fitted by a steepening spectrum due to synchrotron emission only. Our X-ray spectrum is the flattest ever observed for this source. The different X-ray spectral slopes and fluxes, as measured by various satellites, are consistent with relatively little changes of the peak frequency of the synchrotron emission, always located below 10^{17} Hz. We discuss these results in the framework of synchrotron self-Compton models. We found that for the BeppoSAX observation, the synchrotron peak frequency is between 10^{15} and 2.5x10^{16} Hz, depending on the model assumptions.

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G. Tagliaferri, G. Ghisellini, P. Giommi, A. Celotti, M. Chiaberge, L. Chiappetti, I. S. Glass, L. Maraschi, F. Tavecchio, A. Treves, A. Wolter. 2000-12-27. The 0.1-200 keV spectrum of the blazar PKS 2005-489 during an active state. https://doi.org/10.1051/0004-6361%3A20010011

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