The wind speeds, dust content, and mass-loss rates of evolved AGB and RSG stars at varying metallicity

We present the results of our survey of 1612 MHz circumstellar OH maser emission asymptotic giant branch (AGB) stars and red supergiants (RSGs) in the Large Cloud. We have discovered four new circumstellar maser sources in the , and increased the number of reliable wind speeds from IR stars in the LMC 5 to 13. Using our new wind speeds, as well as those from Galactic sources, have derived an updated relation for dust driven winds: vexp / ZL0:4. We compare sub-solar metallicity LMC OH/IR stars with carefully selected samples of metal-rich OH/IR stars, also at known distances, in the Galactic Centre and Bulge. For 8 of the Bulge stars we derive pulsation periods for the first , using near-IR photometry from the VVV survey. We have modeled our LMC /IR stars and developed an empirical method of deriving gas-to-dust ratios and loss rates by scaling the models to the results from maser profiles. We have this also for samples in the Galactic Centre and Bulge and derived a new loss prescription that includes luminosity, pulsation period, and gas-to-dust ratio _M = 1:06+3:5