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Triggered massive-star formation at the border of the HII region Sh 104

L. Deharveng·B. Lefloch·A. Zavagno·J. Caplan·A. P. Whitworth·D. Nadeau·S. Martin
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Abstract

We present millimetre-line imaging of the Galactic HII region Sh 104. We show that it is surrounded by a ring of molecular gas and dust. Four large molecular condensations are regularly spaced around the ring. These condensations are themselves fragmented and contain several massive dense cores. A deeply embedded cluster is observed in the near IR towards the largest condensation. It contains at least one massive star ionizing an ultra-compact HII region. The Sh 104 region is a good illustration of the `collect and collapse' model for star formation triggered by the expansion of an HII region.

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L. Deharveng, B. Lefloch, A. Zavagno, J. Caplan, A. P. Whitworth, D. Nadeau, S. Martin. 2003-08-31. Triggered massive-star formation at the border of the HII region Sh 104. https://doi.org/10.1051/0004-6361%3A20031157

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