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A view of PKS 2155-304 with XMM-Newton Reflection Grating Spectrometers

I. Cagnoni·F. Nicastro·L. Maraschi·A. Treves·F. Tavecchio
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Abstract

We present the high resolution X-ray spectrum of the BL Lac object PKS 2155-304 taken with the RGS units onboard XMM-Newton in November 2000. We detect a OVII Kalpha resonant absorption line from warm/hot local gas at 21.59A (~4.5 sigma detection). The line profile is possibly double peaked. We do not confirm the strong 20.02 A absorption line seen with Chandra and interpreted as z~0.05 OVIII Kalpha. A 3sigma upper limit of 14 mA on the equivalent width is set. We also detect the ~23.5 A interstellar OI 1s-->2p line and derive a factor <=1.5 subsolar O/H ratio in the ISM along PKS 2155-304 line of sight.

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I. Cagnoni, F. Nicastro, L. Maraschi, A. Treves, F. Tavecchio. 2003-11-26. A view of PKS 2155-304 with XMM-Newton Reflection Grating Spectrometers. https://doi.org/10.1086/381698

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