Australian east-west baseline interferometer observations at 2.3 GHz

In 1967 the two Australian stations of the NASA?JPL Deep Space Network, DSS41 at Island Lagoon near Woomera and DSS42 at Tidbinbilla near Canberra, were operated as an intensity interferometer (Gubbay and Robertson 1967). At the operating frequency of 2·3 GHz, the baseline is 9 × 106 wavelengths in extent and runs 15° south of east from DSS41. In the work reported by Gubbay and Robertson, the flux from the radio source 3C 273 was found to be partially correlated. This note concerns later measurement over the same baseline using an intermediate interferometer (Clark 1968).