DUST EMISSION FROM L1641N - AN OPTICALLY THICK CIRCUMSTELLAR DISK

We have obtained high angular resolution (1 ''-3 '') continuum maps of the young stellar object L1641N (IRAS 05338-0624) at 2.0 mm, 7.0 mm, and 1.3 cm. The source positions at the three wavelengths coincide with a very red near-IR source detectable only at lambda > 4 mu m. The source is unresolved at 1.3 cm with a 1 '' beam (or 250 AU in radius). When combined with flux densities at other wavelengths, we find that the spectral energy distribution at mm wavelengths can be well fit by a power law with a spectral index of 2.1 +/- 0.2, and that the distribution between 2.0 mm and 6 cm can be well fit by a combination of the dust emission and optically thin free-free emission. Among several possible interpretations of the observed continuum spectrum, we favor optically thick dust emission from within 250 AU of L1641N, and the most probable origin of such emission is a circumstellar disk around the young star. We also discuss the physical properties of the optically thick disk.