Small Magellanic Cloud Be stars: colour-magnitude relations and   mass-loss
  We present an analysis of optical lightcurves of Small Magellanic Cloud Be-type stars. Observations show that (1) optical excess flux is correlated with near-IR excess flux indicating a similar mechanism and (2) the lightcurves can trace out ``loops'' in a colour-magnitude diagram. A simple model for the time dependent bound-free and free-free emission produced by an outflowing circumstellar disk gives reasonable fits to the observations. 
W.J. de Wit, H.J.G.L.M. Lamers, J.B. Marquette, J.P. Beaulieu