A Detailed Analysis of the Radio Emission from the Symbiotic Star RX Puppis

Radio observations of the symbiotic star RX Puppis made with the VLA are analyzed. These radio data, together with optical data, show that RX Pup is undergoing a period of enhanced mass loss in the form of ionized gas that probably began in the late 1970s, accompanied by an increase in the color temperature of a hot secondary. There is no discernible departure from circular symmetry in the radio visibility data, and it is likely that the wind is nearly spherically symmetric. The temperature of the wind gas is about 9300 K, qualitatively consistent with photoionization by the hot companion. The time scale for the development of detectable centimeter radio emission from this new phase of mass loss suggests that the ejection velocity is greater than 60 km/s. The corresponding mass loss rate is 4.2 x 10 to the -6th solar mass/yr or greater.