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IRAS 06562-0337, The Iron Clad Nebula: A New Young Star Cluster

D. Alves·D. W. Hoard·B. Rodgers
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Abstract

IRAS 06562-0337 has been the recent subject of a classic debate: proto-planetary nebula or young stellar object? We present the first 2 micron image of IRAS 06562-0337, which reveals an extended diffuse nebula containing approximately 70 stars inside a 30 arcsec radius around a bright, possibly resolved, central object. The derived stellar luminosity function is consistent with that expected from a single coeval population, and the brightness of the nebulosity is consistent with the predicted flux of unresolved low-mass stars. The stars and nebulosity are spatially coincident with strong CO line emission. We therefore identify IRAS 06562-0337 as a new young star cluster embedded in its placental molecular cloud. The central object is likely a Herbig Be star, M approx 20 M_sun, which may be seen in reflection. We present medium resolution, high S/N, 1997 epoch optical spectra of the central object. Comparison with previously published spectra shows new evidence for time variable permitted and forbidden line emission, including SiII, FeII, [FeII], and [OI]. We suggest the origin is a dynamic stellar wind in the extended, stratified atmosphere of the massive central star in IRAS 06562-0337.

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D. Alves, D. W. Hoard, B. Rodgers. 1998-03-31. IRAS 06562-0337, The Iron Clad Nebula: A New Young Star Cluster. https://doi.org/10.1086/300402

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