Strong Response of the very broad h$\beta$ Emission Line in Luminous
  Radio-Quite Quasar pg1416-129
  We report new spectroscopic observations performed in 2010 and 2011 for
luminous radio-quite quasar PG 1416-129. Our new spectra with high quality
cover both H$\beta$ and H$\alpha$ regions, and show negligible line profile
variation within a timescale of one year. The two spectra allow us to study the
variability of the Balmer line profile by comparing the spectra with the
previous ones taken at 10 and 20 years ago. By decomposing the broad Balmer
emission lines into two Gaussian profiles, our spectral analysis suggests a
strong response to the continuum level for the very broad component, and
significant variations in both bulk blueshift velocity/FWHM and flux for the
broad component. The new observations additionally indicate flat Balmer
decrements (i.e., too strong H$\beta$ emission) at the line wings, which is
hard to be reproduced by recent optically thin models. With these observations
we argue that a separate inner optically thin emission-line region might not be
necessary in the object to reproduce the observed line profiles.
