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Hubble Space Telescope NICMOS Imaging of W3 IRS 5: A Trapezium in the Making?

S. T. Megeath·T. L. Wilson·M. Corbin
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Abstract

We present Hubble Space Telescope NICMOS imaging of W3 IRS 5, a binary high-mass protostar. In addition to the two protostars, NICMOS images taken in the F222M and F160W filters show three new 2.22 micron sources with very red colors; these sources fall within a region 5600 AU in diameter, and are coincident with a 100 solar mass dense molecular clump. Two additional point sources are found within 0.4'' (800 AU) of one of the high-mass protostars; these may be stellar companions or unresolved emission knots from an outflow. We propose that these sources constitute a nascent Trapezium system in the center of the W3 IRS 5 cluster containing as many as five proto OB stars. This would be the first identification of a Trapezium still deeply embedded in its natal gas.

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S. T. Megeath, T. L. Wilson, M. Corbin. 2005-03-09. Hubble Space Telescope NICMOS Imaging of W3 IRS 5: A Trapezium in the Making?. https://doi.org/10.1086/429720

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