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IRAS 04000+5052: A not so compact, not so metal-poor HII region

Cesar Esteban·Luis Lopez-Martin·Angel R. Lopez-Sanchez·Bernabe Cedres·Jorge Garcia-Rojas
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Abstract

We present new observations of IRAS 04000+5052, a Galactic HII region associated with a young stellar cluster and possibly located at the Perseus arm. Contrary to previous claims, we have found that this object is not a compact metal-poor HII region. The electron density and chemical composition of the nebula are similar to those of normal HII regions of the Galactic disk. The radial velocity of the ionized gas coincides with that obtained from CO observations, indicating that the nebula is associated with a molecular cloud. Probably, the ionizing source of the HII region is a Herbig Be star of B0.5 spectral type.

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Cesar Esteban, Luis Lopez-Martin, Angel R. Lopez-Sanchez, Bernabe Cedres, Jorge Garcia-Rojas. 2004-06-07. IRAS 04000+5052: A not so compact, not so metal-poor HII region. https://doi.org/10.1086/422894

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