The X-ray emission from broad absorption line quasars
نویسندگان
چکیده
Pointed ASCA observations as well as archival ROSAT data are used for a study of the X-ray emission of the three BAL Quasars LBQS 2212-1759, PG 1411+442, and PG 0043+039. All three objects are found to be X-ray quiet, possibly due to substantial intrinsic absorption with NH > 1023 cm−2 but might have intrinsically a more typical spectral energy distribution. This picture is supported by explicit spectral fits to the combined ROSAT/ASCA data of the nearby bright object PG 1411+442. An analysis of the large number of radio-quiet quasars not detected in the ROSAT All-Sky Survey indicates that perhaps only a small fraction of BAL quasars have not been recognized before and that the number of intrinsically X-ray quiet quasars must be small.
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