Observations and analysis of the southern binary R Arae

This paper investigates the nature of the relatively bright eclipsing variable R Arae (HD 149730A), which has an orbital period of 4.42509 d, from the analysis of photometric UBV observations. The analyses indicate the relative radius of the secondary star is of the order of 0.20. This value is well below the limit which would classify the system as a semidetached binary. These results seem to be somewhat discordant with the spectroscopic and general photometric nature of the system, all of which suggest mass transfer processes to be occurring (therefore a possible semidetached status). (Author)