Reverberation in the UV-Optical Continuum Brightness Fluctuations of
  MACHO Quasar 13.5962.237
  We examine the nature of brightness fluctuations in the UV-Optical spectral
region of an ordinary quasar with 881 optical brightness measurements made
during the epoch 1993 - 1999. We find evidence for systematic trends having the
character of a pattern of reverberations following an initial disturbance. The
initial pulses have brightness increases of order 20% and pulse widths of 50
days, and the reverberations have typical amplitudes of 12% with longer mean
pulse widths of order 80 days and pulse separations of order 90 days. The
repeat pattern occurs over the same time scales whether the initial disturbance
is a brightening or fading. The lags of the pulse trains are comparable to the
lags seen previously in reverberation of the broad blue-shifted emission lines
following brightness disturbances in Seyfert galaxies, when allowance is made
for the mass of the central object. In addition to the burst pulse trains, we
find evidence for a semi-periodicity with a time scale of 2 years. These strong
patterns of brightness fluctuations suggest a method of discovering quasars
from photometric monitoring alone, with data of the quality expected from large
brightness monitoring programs like Pann-Stars and LSST.
