Vanishing Absorption and Blueshifted Emission in FeLoBAL Quasars
  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~\AA\ 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 \mgii\ and UV \feii\ lines in several FeLoBAL
quasars are blueshifted by thousands of \kms\ relative to the \Hb\ emission
line peak. We suggest that such emission arises in the outflowing winds
normally seen only in absorption.
