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High Angular Resolution Mid-infrared Imaging of Young Stars in Orion BN/KL

L. J. Greenhill·D. Y. Gezari·W. C. Danchi·J. Najita·J. D. Monnier·P. G. Tuthill
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Abstract

We present Keck LWS images of the Orion BN/KL star forming region obtained in the first multi-wavelength study to have 0.3-0.5" resolution from 4.7 to 22 microns. The young stellar objects designated infrared source-n and radio source-I are believed to dominate the BN/KL region. We have detected extended emission from a probable accretion disk around source-n but infer a stellar luminosity on the order of only 2000 Lsun. Although source-I is believed to be more luminous, we do not detect an infrared counterpart even at the longest wavelengths. However, we resolve the closeby infrared source, IRc2, into an arc of knots ~1000 AU long at all wavelengths. Although the physical relation of source-I to IRc2 remains ambiguous, we suggest these sources mark a high density core (10^7-10^8 pc^-3 over 1000 AU) within the larger BN/KL star forming cluster. The high density may be a consequence of the core being young and heavily embedded. We suggest the energetics of the BN/KL region may be dominated by this cluster core rather than one or two individual sources.

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L. J. Greenhill, D. Y. Gezari, W. C. Danchi, J. Najita, J. D. Monnier, P. G. Tuthill. 2004-02-18. High Angular Resolution Mid-infrared Imaging of Young Stars in Orion BN/KL. https://doi.org/10.1086/386544

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