SPATIAL-RESOLUTION OF THE R-AQUARII BINARY-SYSTEM

We report continuum VLA observations at 7 mm that have resolved the st ellar components in the R Aqr binary system. R Aqr was simultaneously probed in both a 50 MHz bandpass containing lineless continuum emissio n associated with the hot companion/accretion disk and a 3.125 MHz ban dpass containing the spectral line upsilon = 1, J = 1-0, SiO maser emi ssion associated with the long-period-variable (LPV) envelope. The off set between the two stars is 55 +/- 2 mas with a position angle of sim ilar to 18 degrees +/- 2 degrees relative to the LPV, providing the fi rst data point for a subsequent monitoring program to determine precis ely the binary orbit that is suspected to be highly elliptical and hav e a period of similar to 44 yr. We evaluate these first observations i n the context of constraints placed on the orbital geometry of the sys tem and obtain a geometrical distance of similar to 200 pc to R Aqr. W e also report spectral line VLA observations at this same epoch that c onfirm that the SiO maser spots have a ringlike morphology, as previou sly reported by other investigators using the VLBA.