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Submillimeter Array 440$μ$m/690GHz line and continuum observations of Orion-KL

H. Beuther·Q. Zhang·M. J. Reid·T. R. Hunter·M. Gurwell·D. Wilner·J. -H. Zhao·H. Shinnaga·E. Keto·P. T. P. Ho·J. M. Moran·S. -Y. Liu
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Abstract

Submillimeter Array observations of Orion-KL at 1'' resolution in the 440mu/690GHz band reveal new insights about the continuum and line emission of the region. The 440mu 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 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 non-detection of SMA1 at cm 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 the sources I, SMA1 and the hot core peak position. An analysis of the CH$3CN(37_K-36_K) K-ladder (K=0...3) indicates a warm gas component of the order 600+-200K. In addition, we detect a large fraction (~58%) of unidentified lines and discuss the difficulties of line identifications at these frequencies.

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H. Beuther, Q. Zhang, M. J. Reid, T. R. Hunter, M. Gurwell, D. Wilner, J. -H. Zhao, H. Shinnaga, E. Keto, P. T. P. Ho, J. M. Moran, S. -Y. Liu. 2005-09-26. Submillimeter Array 440$μ$m/690GHz line and continuum observations of Orion-KL. https://doi.org/10.1086/498015

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