L1551NE - Discovery of a binary companion

L1551NE is a very young (class 0 or I) low-mass protostar located close to the well-studied L1551 IRS 5. Here we present evidence, from 1.3 mm continu um interferometric observations at similar to 1 " resolution, for a binary companion to L1551NE. The companion, whose 1.3 mm flux density is -1/3 that of the primary component, is located 1." 43 (similar to 230 AU at 160 pc) to the southeast. The millimeter-wave emission from the primary component m ay have been just barely resolved, with a deconvolved size of similar to 0. '82 x 0.'70 (similar to 131 x 112 AU), The companion emission was unresolve d (<100 AU), The pair is embedded within a flattened circumbinary envelope of size similar to 5.'4 x 2.'3 (similar to 860 x 370 AU). The masses of the three components (i.e., from the circumstellar material of the primary sta r and its companion and the envelope) are approximately 0.044, 0.014, and 0 .023 M., respectively.