NEW BINARY YOUNG STARS IN THE TAURUS AND OPHIUCHUS STAR-FORMING REGIONS

We have observed 30 lunar occultations (LO) in the near infrared of so urces in the Taurus and Ophiuchus star-forming regions (SFRs) during t hree runs from September 1991 to January 1993. Twenty-six of the sourc es were proper young stellar objects (YSOs), the remaining four were f ield stars (or at least suspected to be). Our observations have led to the discovery of the following new binary systems: HK Tau/G2, IW Tau, HP Tau and HP Tau/G3 in Taurus, and GSS 35 and VSSG 14 in Ophiuchus. In the case of the known binary Haro 6-10 (Leinert & Haas 1989), our o bservation shows the presence of extended emission around the main com ponent, while nothing can be said about the circumbinary disk suggeste d by Menard et al. (1993). Additionally, FY Tau should be considered a suspected binary, and we find the field star VSS 35 to be double. We discuss the implications of these new findings: at least in the Taurus SFR, where most of our events were observed, the currently emerging v iew that most -if not all- stars begin their life as members of binary or multiple systems (Ghez et al. 1993, Leinert et al. 1993, Simon et al. 1994) appears strengthened; a statistical discussion of all LO obs ervations obtained so far in the Taurus and Ophiuchus SFRs will be giv en by Simon et al. (1994).