The orbital elements of R Aquarii

Radial velocity information has been collected on R Aquarii since 1946. Various stellar radiating systems have been used to determine the velocity centroid of the long-period variable. These velocity values have been combined and analyzed in an attempt to extract the orbital parameters of the binary star system. The analysis produced an orbital period of 34.6 ± 1.2 yr, an eccentricity of 0.52 ± 0.08, and a projected semimajor axis of 3.5 ± 0.4 AU. If accurate, these values would indicate a Roche lobe overflow at periastron and significant effects on the mass transfer of the system. The accuracy of these results is suspect due to inconsistencies with other parameters of the system.