DISCOVERY OF 5 PRE-MAIN-SEQUENCE BINARIES IN TAURUS

We report the progress of our infrared K band lunar occultation search for binaries among pre-main sequence stars. From the fall of 1986 to the fall of 1989, 13 objects have been observed, all in the Taurus star-forming region. Five new binaries have been discovered: DF Tau, DI Tau, FS Tau (Haro 6-5) A, FV Tau (Haro 6-8), and FW Tau, with projected separations ranging from 0″.01 to 0″.57. Including results reported previously, we have, to date, surveyed a total of 31 objects, 21 in Taurus and 10 in Ophiuchus, and have found nine double systems. The detected binary frequency (0.29) seems consistent with that of the solar-type main-sequence field stars.