Evidence Against Broad Absorption Lines in the X‐Ray–bright Quasar PG 1416−129

Abstract

Recent results from the ROSAT All-Sky Survey and from deep ROSAT pointings reveal that broad absorption line quasars (BALQSOs) are weak in the soft X-ray bandpass (αox > 1.8) in comparison to QSOs with normal OUV spectra ( = 1.4). One glaring exception appeared to be the nearby BALQSO PG 1416-129, which is a bright ROSAT source showing no evidence for intrinsic soft X-ray absorption. We present here our new HST Faint Object Spectrograph (FOS) spectrum of PG 1416-129, in which we find no evidence for BALs. We show that the features resulting in the original BAL classification, based on IUE spectra, were probably spurious. On the basis of UV, X-ray, and optical evidence, we conclude that PG 1416-129 is not now, and has never been, a BALQSO. Our result suggests that weak soft X-ray emission is a defining characteristic of true BALQSOs. If BALQSOs indeed harbor normal intrinsic spectral energy distributions, their observed soft X-ray weakness is most likely the result of absorption. The ubiquitous occurrence of weak soft X-ray emission with UV absorption (BALs) thus suggests absorbers in each energy regime that are physically associated, if not identical.