The variability of UV/optical Fe ii emission lines in a QSO: SDSS J142052.43+525622.4

The variability of the UV and optical Fe ii emission is investigated for a QSO, SDSS J142052.43+525622.4 ( z = 0.676 ), with 50 spectroscopic observations covering 1047 d in the observed frame. This QSO is selected from the Sloan Digital Sky Survey-Reverberation Mapping (SDSS-RM) project. Using multiple components to model the pseudo-continuum and emission lines (Mg ii , H β , [O iii ], Fe ii ), some results are outlined as follows: (i) Based on the distribution of the [O iii ] 5007 Å luminosity, the flux-calibration uncertainty is about 7.8