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XMM-Newton Observations of Two BAL QSOs: Q1246-057 and SBS1542+541

D. Grupe·S. Mathur·M. Elvis
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Abstract

We report on the results of XMM-Newton observations of two Broad Absorption Line Quasars (BAL QSOs), Q1246-057 and SBS 1542+541. Unprecedented sensitivity of XMM allows spectral analysis of these X-ray weak sources. The X-ray spectral data of these sources can be fitted by a power-law with alpha_X=1.0-1.2 and either a partially covering absorber or an ionized absorber model. Rest frame UV spectroscopy together with polarimetry favors the model with a partially covering absorber with column density a few times 10^22 cm^-2 and a covering fraction of about 0.80. After correcting for absorption, the X-ray loudness of these BAL QSOs appears to be similar to other, unabsorbed quasars. The mystery of X-ray weakness of BAL QSOs appears to be all but solved, with strong absorption being the primary reason. With the available X-ray data, however, the issue of whether BAL QSOs represent highly accreting/ younger population of quasars remains unsettled.

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D. Grupe, S. Mathur, M. Elvis. 2003-05-16. XMM-Newton Observations of Two BAL QSOs: Q1246-057 and SBS1542+541. https://doi.org/10.1086/377141

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