Qualitative reproduction of stellar H2O maser morphology - I. Results at asingle stellar phase

We attempt to reproduce the observed morphologies of stellar H2O maser emis sion by combining a hydrodynamic pulsation model of a long-period variable (LPV) star with an H2O maser model. These numerical simulations yield synth etic maser lineshapes and interferometry images as a function of stellar pu lsation phase. The results at a single stellar phase are presented here for 22, 321, 325 and 183 GHz masers. We compare our simulated data with the ob served features of stellar H2O masers, and make predictions of the existenc e of new masers in the circumstellar environment. We also predict the appea rance of 183, 321 and 325 GHz maser images which may be observable in futur e using the Atacama Large Millimetre Array (ALMA). These simulations correc tly locate the shell of 22 GHz masers in the region of the circumstellar en velope (CE) in which material is being accelerated to form the steadily-out owing stellar wind.