Massive Protoplanetary Disks in the Trapezium Region

We determine the disk mass distribution around 336 stars in the young (∼ 1 Myr) Orion Nebula cluster by imaging a 2. 5 × 2. 5 region in λ3 mm continuum emission with the Owens Valley Millimeter Array. For this sample of 336 stars, we observe 3 mm emission above the 3σ noise level toward ten sources, six of which have also been detected optically in silhouette against the bright nebular background. In addition, we detect 20 objects in 3 mm continuum emission that do not correspond to known near-IR cluster members. Comparisons of our measured fluxes with longer wavelength observations enable rough separation of dust emission from thermal free-free emission, and we find substantial dust emission toward most objects. For the sample of ten objects detected at both 3 mm and near-IR wavelengths, eight exhibit substantial dust emission. Excluding the two high-mass stars (θOriA and the BN object) and assuming a gas-to-dust