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Star formation in IC 1848 A

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Abstract

Recent far-infrared photometric and near-infrared spectroscopic observations of IC 1848 A/W5 East are reported. The source appears to be excited by a star of spectral type near B0, which can explain the far-infrared luminosity, 2 micron spectrum, radio continuum, and radio molecular observations. Although this star appears surrounded by a local very compact H II region, the density over a large scale is relatively low. This puts constraints on models for the formation of this star.
1980ApJ...242..609T
1980ApJ...242..609T
1980ApJ...242..609T
1980ApJ...242..609T
1980ApJ...242..609T
1980ApJ...242..609T
... Early studies of the bright-rimmed cloud IC 1848A (W5A/ S201) at the border of the giant H II region suggested that star formation in the cloud had been triggered by the expansion of the H II region (Loren & Wootten 1978;Thronson et al. 1980). Wilking et al. (1984) also found another possible site of feedback-driven star formation in the northern cloud (W5NW). ...
... The sparse groups (A, E, and H) formed along the edge of the H II regions. A number of previous studies have proposed that W5 is the site of feedback-driven star formation (Loren & Wootten 1978;Thronson et al. 1980;Wilking et al. 1984;Karr & Martin 2003;Koenig et al. 2008a). Koenig et al. (2008a) suggested that the radiatively driven implosion mechanism (Klein et al. 1985) operates on a small spatial scale, e.g., cometary globules or elephant trunk structures in the southern ridge of W5 West, while the collect-and-collapse mechanism Figure 12. ...
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