Vanishing Absorption and Blueshifted Emission in FeLoBAL Quasars
Abstract
We study the dramatic decrease in iron absorption strength in the iron low-ionization broad absorption line quasar SDSS J084133.15+200525.8. We report on the continued weakening of absorption in the prototype of this class of variable broad absorption line quasar, FBQS J140806.2+305448. We also report a third example of this class, SDSS J123103.70+392903.6; unlike the other two examples, it has undergone an increase in observed continuum brightness (at 3000~\ rest-frame) as well as a decrease in iron absorption strength. These changes could be caused by absorber transverse motion or by ionization variability. We note that the \ and UV \ lines in several FeLoBAL quasars are blueshifted by thousands of \ relative to the \ emission line peak. We suggest that such emission arises in the outflowing winds normally seen only in absorption.
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