Surface Brightness Fluctuations as Stellar Population Indicators
  Surface Brightness Fluctuations (SBF) can provide useful information about
the unresolved stellar content of early-type galaxies and spiral bulges. The
absolute SBF magnitude Mbar in a given passband depends on the properties of
the stellar population and can be predicted by population synthesis models. SBF
measurements in different bandpasses are sensitive to different evolutionary
stages within the galaxy stellar population. Near-IR SBF magnitudes are
sensitive to the evolution of stars within the AGB phase, especially the
thermally pulsing AGB, while SBF in the blue and UV are sensitive to the hot
horizontal branch and post-AGB stages. Thus, multi-band SBF studies can
constrain important evolutionary parameters. Empirically, SBF data at the red
end of the optical spectrum (i, z, and potentially y) remain excellent distance
indicators. I briefly review some recent work on stellar populations using SBF,
primarily from an observational point of view.
