High energy properties of PKS 1830-211


Abstract in English

We report on an analysis of X- and $gamma$-ray observations of PKS 1830-211, based on the long-term campaigns carried out by emph{INTEGRAL} and COMPTEL. The emph{INTEGRAL} data currently available present a $33sigma$ significance detection in the 20-100 keV band, while the COMPTEL 6-years data provide a $5.2sigma$ significance detection in the 1-3 MeV energy band. At hard X-rays, emph{INTEGRAL} and supplementary emph{SWIFT} observations show flux variability on timescales of months. At $gamma$-rays, the source shows persistent emission over years. The hard X-ray spectrum is well represented by a power-law model, with $Gamma sim 1.3$ in the 20-250 keV band. This photon index is well consistent with the previous report of $Gamma sim 1.3$ obtained at $E > 3.5$ keV from the best fit of emph{XMM-Newton} data with a broken power law model. The joint emph{XMM-Newton}/emph{INTEGRAL} spectrum presented here is then fit with a broken power-law model and the parameters are refined compared to the previous. The results show the photon index changes from $sim 1.0$ to $sim 1.3$ at a break energy $sim 4$ keV. At MeV energies, the spectrum softens to $Gamma sim 2.2$. These results, together with the EGRET measurement at $E ge 100$ MeV, constitute a broad-band spectrum containing the peak of the power output at MeV energies, similar to most high-luminosity $gamma$-ray blazars. The measured spectral characterstics are then discussed in the framework of the gravitational lens effects.

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