The BIMA search for circumstellar disks in Trapezium
Session 9 -- Protostars, Young Stars and Stellar Accretion Disks
Display presentation, Monday, June 12, 1995, 9:20am - 6:30pm

## [9.09] The BIMA search for circumstellar disks in Trapezium

L.W.Looney,L.G.Mundy,E.L.Lada (Maryland)

Observations of the 86.2 GHz continuum emission from the Trapezium cluster region were obtained using the new extended baseline configuration of the 6-element BIMA array. This new, high resolution configuration provides a synthesized beam of 0.76$^{\prime\prime}$x 1.53$^{\prime\prime}$, enabling the separation of individual stars and the filtering of emission from the extended H II region of M42 on spatial scales greater than 15$^{\prime\prime}$. We report on the search for circumstellar disks in Trapezium with a mass sensitivity of 0.11 to 0.15 $M_{\sun}$.

Within the Trapezium region resides a population of young stars with associated compact ionized gas emission. Several recent studies have argued that the ionized gas around these stars arises from ionization and oblation of their circumstellar disks by UV radiation from the nearby O7 V star, $\Theta^{1}$C. This region provides the opportunity to study the evolution of circumstellar disks within a star forming cluster and compare to past work which concentrated on disks in an isolated environment. Using these millimeter observations, we directly probe the thermal dust emission of purported circumstellar disk systems in Trapezium and thereby make a direct limit on circumstellar disk masses in a cluster region.