1999ApJ...522..297H

We report a kinematic study of the symbiotic star system R Aqr derived from [N II] λ6584 emission observations with a Fabry-Perot imaging spectrometer. The [N II] spatial structure of the R Aqr jet, first observed circa 1977, and surrounding hourglass-shaped nebulosity, due to an explosion ∼660 yr ago, are derived from 41 velocity planes spaced at ∼12 km.s^–1 intervals. Fabry-Perot imagery shows that the elliptical nebulosity making up the waist of the hourglass shell is consistent with a circular ring expanding radially at 55 km.s^–1 as seen at an inclination angle i∼70°. With respect to the position of R Aqr, at optical and radio wavelengths the jet is made up of a northeast component and a less intense, more amorphous southwest component. The [N II] Fabry-Perot data cube demonstrates that the two jet components possess quite different intensity-velocity structures which represent collimated flow in opposite directions. We offer an idealized schematic model for the R Aqr jet motion which results in a small-scale helical structure forming around a larger scale helical path. The implications of such a jet model are discussed. We present a movie showing a side-by-side comparison of the spatial structure of the model and the data as a function of the 41 velocity planes.