VLBI Observations of Stellar Binary Systems

Abstract

Since 1982 July we have been engaged in a systematic investigation of the milliarcsecond structure of the radio emission from several binary star systems, mainly in the RS CVn class (Hall, 1976). The first few observations utilized the MkII VLBI recording scheme, but no useful data were obtainable because of the relatively low flux levels involved Beginning in 1982 December, we have been using the MkIII system with large telescopes and have successfully detected seven binary systems (UX Arietis, HR 1099, Algol, II Peg, σ Crb, and the distant system LSI 61°303). A summary of the three experiments already completed is given in Table 1.