We have carried out a survey with the Chandra X-Ray Observatory of a sample of 10 bright broad absorption line (BAL) quasars (QSOs). Eight of 10 sources are detected. The six brightest sources have only high-ionization BALs (hiBALs), while the four faintest all show low-ionization BALs (loBALs). We perform a combined spectral Ðt for hiBAL QSOs (384 counts total ; 0.5È6 keV) to determine the mean spectral parameters of this sample. We derive an underlying best-Ðt power-law slope !\ 1.8^ 0.35… CONTINUE READING
FIG. 2.ÈJoint (1, 2, and 3 p) conÐdence intervals for spectral Ðt parameters for our simultaneous Ðt to the six Chandra BAL QSOs with more than 20 counts using Model C (Table 3 and ° 3). L eft : Redshifted intrinsic absorption and power-law spectral index !. Right : ConÐdence intervals for redshifted absorption and covering fraction.