摘要
Submillimeter Array observations of Orion KL at ∼1″ resolution in the 440 μm/690 GHz band reveal new insights about the continuum and line emission of the region. The 440 μm continuum flux density measurement from source I allows us to differentiate among the various proposed physical models. Source I can be well modeled by a "normal" protostellar spectral energy distribution (SED) consisting of a proton-electron free-free emission component at low frequencies and a strong dust component in the submillimeter bands. Furthermore, we find that the protostellar object SMA1 is clearly distinct from the hot core. The nondetection of SMA1 at centimeter and infrared wavelengths suggests that it may be one of the youngest sources in the entire Orion KL region. The molecular line maps show emission mainly from source I, SMA1, and the hot core peak position. An analysis of the CH 3 CN(37 k -36 k ) /C-ladder (K = 0, . . . ,3) indicates a warm gas component of the order of 600 ±200 K. In addition, we detect a large fraction (∼58%) of unidentified lines and discuss the difficulties of line identification at these frequencies. © 2006. The American Astronomical Society. All rignts reserved.