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تسجيل مستخدم جديدAn accretion disc origin for the `X-ray broad line region in 1H0707-495
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A. J. Blustin
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We use a 380 ks XMM-Newton high-resolution RGS spectrum to look for narrow spectral features from the nuclear environment of 1H0707-495. We do not find any evidence of a line-of-sight ionized wind (warm absorber). We do, however, detect broad emission lines, of width ~5000 km s^-1, consistent with O VIII Ly-alpha, N VII Ly-alpha, C VI Ly-alpha and a Fe XIX/Fe XX/Ne IX He-alpha blend. Intriguingly, these lines have both blueshifted and redshifted components, whose velocity shifts are consistent with an origin in an accretion disc at ~1600 R_g from the black hole. The features can be interpreted as the narrow line cores of the disc reflection spectrum, thus providing independent support for the discline interpretation of the X-ray spectrum of 1H0707-495. We discuss the relevance of our findings for the `X-ray broad line region in other Seyferts, and for the origins of the optical broad line region itself.
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