Description
We study stars and gas in and around the HII region Sh 2-217 to see if the various physical parameters derived from the data (such as column densities, masses, sizes, and timescales) are consistent with the predictions of a simple model of the collect-and-collapse mechanism. This should indicate whether stars forming in molecular gas at the borders of the HII region could have been triggered by the expansion of the ionized gas. We observed the emission of various molecules and transitions towards Sh 2-217, and obtained both near-infrared photometry in the H and K bands, and near-infrared images in [FeII] and H2 narrow-band filters of the stars in a molecular condensation at the edge of the HII region, where an UC HII region is also located.
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