Optical and X‐Ray Spectroscopy of 1E 0449.4−1823: Demise of the Original Type 2 QSO

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Abstract
New optical spectra of the original narrow-line quasar 1E 0449.4-1823 show that it now has broad emission lines of considerable strength, eliminating it as a "type 2 QSO" candidate. Although broad emission line components were probably weakly present in 1981 and 1984, they have certainly increased in strength and are accompanied by Balmer continuum emission that makes the spectrum bluer than it was previously. We suggest that the behavior of 1E 0449.4-1823 is the same as that of some Seyfert 1.8 and 1.9 galaxies, in which Goodrich attributed long-term variations of their broad Balmer lines to dynamical motions of obscuring material located in or around the broad-line region. The optical continuum and broad emission line regions of 1E 0449.4-1823 may still be partly covered in our line of sight, which would explain its large forbidden-line equivalent widths and flat αox relative to other low-redshift QSOs. Also present are apparent absorption features in the broad Balmer lines and in Mg II, which may be related to the past obscuration and current emergence of the broad-line region. However, it is difficult to distinguish absorption from broad emission line peaks that are displaced in velocity; we consider the latter a plausible competing interpretation of these peculiar line profiles. An ASCA X-ray spectrum of 1E 0449.4-1823 can be fitted with a power law of Γ=1.63+ 0.12−0.09, intrinsic NH < 9 × 1020 cm-2, and no Fe Kα line emission. Its 2-10 keV luminosity is 6.7 × 1044 ergs s-1. Thus, there is no evidence for Seyfert 2 properties in the X-ray emission from 1E 0449.4-1823, which resembles that of an ordinary QSO. With regard to the still hypothetical type 2 QSOs, we argue that there is little evidence for the existence of any among X-ray-selected samples.
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