THE CIRCUMSTELLAR DISK MASS DISTRIBUTION IN THE ORION TRAPEZIUM CLUSTER

We present the results of a submillimeter interferometric survey of circumstellar disks in the Trapezium cluster of Orion. We observed the 880 mu m continuum emission from 55 disks using the Submillimeter Array,(1) and detected 28 disks above 3 sigma significance with fluxes between 6 and 70 mJy and rms noise between 0.7 and 5.3 mJy. Dust masses and upper limits are derived from the submillimeter excess above free-free emission extrapolated from longer wavelength observations. Above our completeness limit of 0.0084 M-circle dot, the disk mass distribution is similar to that of Class II disks in Taurus-Auriga and rho Ophiuchus but is truncated at 0.04 M-circle dot. We show that the disk mass and radius distributions are consistent with the formation of Trapezium cluster disks similar to 1 Myr ago and subsequent photoevaporation by the ultraviolet radiation field from theta(1) Ori C. The fraction of disks that contain a minimum mass solar nebula within 60 AU radius is estimated to be 11%-13% in both Taurus and the Trapezium cluster, which suggests the potential for forming Solar Systems is not compromised in this massive star-forming region.