Properties of the Molecular Clump and the Associated Ultracompact H II Region in the Gas Shell of the Expanding H II Region Sh 2-104

다국어 초록 (Multilingual Abstract)

We study the physical and chemical properties of the molecular clump hosting a young stellar cluster, IRAS 20160+3636, which is believed to have formed via the ``collect and collapse'' process. Physical parameters of the UC Hii region associated with the embedded cluster are measured from the radio continuum observations. This source is found to be a typical Galactic UC Hii region, with a B0.5 type exciting star, if it is ionized by a single star. We derive a CN/HCN abundance ratio larger than 1 over this region, which may suggest that this clump is being affected by the UV radiation from the Hii region.

참고문헌 (Reference)

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