Millimeter Imaging of HH 24 MMS: A Misaligned Protobinary System

The HH 24 MMS protostellar system was observed in the 6.9 mm continuum with a high angular resolution (0.5"). HH 24 MMS was resolved into two sources. The separation between sources 1 and 2 is ~0.9" or 360 AU. The spectral energy distribution suggests that the 6.9 mm flux is almost entirely from dust. The 6.9 mm image and the spectrum suggest that HH 24 MMS may be a protostellar binary system. Total mass including the accretion disks and the inner protostellar envelope is ~1.4 Msun. Disk masses of sources 1 and 2 are 0.6 and 0.3 Msun, respectively. Both sources are highly elongated. The difference in the position angle of the two disks is ~45 degree, which means that HH 24 MMS is a highly misaligned protobinary system. The misalignment suggests that turbulent fragmentation may be the formation mechanism relevant to the binary systems with a separation of a few hundreds of AU, such as the HH 24 MMS system.