Lynds 1527: An embedded protobinary system in Taurus

Submillimeter continuum maps at 800 mu m of the embedded source IRAS 04368+2557 in L1527 in Taurus show that there are two sources separated by 20 '', or 2800 AU. The secondary source is between 2 and 3 times less luminous than the primary source if both sources have similar spectral energy distributions. Large-scale (CO)-O-18 J = 1 --> 0 emission shows the sources to be embedded in a single dense core, and observations of (CO)-O-18 and (CO)-O-17 show the sources to be associated with a compact region of high-density gas. Three transitions of (CO)-O-18 show a velocity gradient between the two sources. On the smallest size scale, the (CO)-O-18 J = 3 --> 2 emission has a velocity gradient of 3-7 km s(-1) pc(-1). The proximity of the sources in both space and velocity suggest that they are a very young protobinary system. The estimated age of the primary source, 5 x 10(3) yr, is much less than the estimated orbital period, 1.4 x 10(5) yr. The separation and young age of the system indicates that it formed through fragmentation of the dense core during collapse.